214 results on '"Wang, Haipeng"'
Search Results
2. Light and Displacement Compensation-Based iPPG for Heart-Rate Measurement in Complex Detection Conditions.
- Author
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Bi, Shubo, Wang, Haipeng, and Zhang, Shuaishuai
- Subjects
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DISPLACEMENT (Mechanics) , *LIGHT intensity , *MEASUREMENT , *MOTION - Abstract
A light and displacement-compensation-based iPPG algorithm is proposed in this paper for heart-rate measurement in complex detection conditions. Two compensation sub-algorithms, including light compensation and displacement compensation, are designed and integrated into the iPPG algorithm for more accurate heart-rate measurement. In the light-compensation sub-algorithm, the measurement deviation caused by the ambient light change is compensated by the mean filter-based light adjustment strategy. In the displacement-compensation sub-algorithm, the measurement deviation caused by the subject motion is compensated by the optical flow-based displacement calculation strategy. A series of heart-rate measurement experiments are conducted to verify the effectiveness of the proposed method. Compared with conventional iPPG, the average measurement accuracy increases by 3.8% under different detection distances and 5.0% under different light intensities. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
3. Integration of TiO2/ZnIn2S4 p‐n Heterojunction with Titanium Defects to Boost PEC Oxygen Production.
- Author
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Wang, Haipeng and Song, Guang‐Ling
- Abstract
TiO2 is a widely used photoelectric conversion semiconductor material. However, due to its native defects, such as the selective absorption of ultraviolet light and high recombination rate of photogenerated carriers, it exhibits poor photoelectrochemical (PEC) water splitting performance. In this study, intrinsic defect titanium vacancy and semiconductor recombination agents ZnIn2S4 were introduced into an anodization‐annealed TiO2 film (TiO2 NT) to enhance the photoanode activity. The activity‐enhanced TiO2 photoanode (ZIS@TiO2 NT‐EA) was characterized by surface analyses and photoelectrochemical measurements. Mott‐Schottky measurement indicated that the introduction of titanium vacancies into the TiO2 NT changed its semiconductor type from n to p, and significantly reduced its apparent activation energy if compared with the TiO2 NT. In addition, after the ZnIn2S4 nanoparticles were loaded on the TiO2 NT‐EA film, the carrier concentration of the ZIS@TiO2 NT‐EA was nearly 12 times higher than the pristine TiO2 NT. Due to the higher carrier separation efficiency resulting from the formation of p‐n heterojunction between TiO2 and ZnIn2S4, the photocurrent density of the ZIS@TiO2 NT‐EA reached 3.89 mA cm−2 at 1.23 V (
vs . RHE), nearly 3 times higher than that of the original TiO2 NT. Amazingly, the maximum applied bias photon‐to‐current efficiency (ABPE) value of the ZIS@TiO2 NT‐EA photoanode reached 2.15 % at 0.496 V (vs . RHE), which is very competitive if compared with all the reported TiO2 film electrodes in the PEC water splitting application. The incident photon‐to current efficiency (IPCE) of the ZIS@TiO2 NT‐EA photoanode was approximately 40.9% at 300 nm, which was about 3 times higher than that of the TiO2 NT (13.6%). To understand these impressive improvements in water splitting, further analyses were conducted on the effect of the increased titanium vacancy concentration in the TiO2 lattice and the formation of p‐n junction between the TiO2 and ZnIn2S4 on the PEC behaviour, as well as on the charge transfer resistance and separation efficiency of carriers. [ABSTRACT FROM AUTHOR]- Published
- 2024
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- View/download PDF
4. Modeling and analysis of bending and torsional coupling vibration response of multi-piece wet friction clutch.
- Author
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Wang, Haipeng, Bao, Heyun, Zhu, Chu, Lu, Fengxia, and Leng, Sheng
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CLUTCHES (Machinery) , *TORSIONAL vibration , *IRON & steel plates , *ROTATIONAL motion , *ROTORS (Helicopters) , *DIFFERENTIAL equations , *FRICTION - Abstract
The vibration response of the multi-piece wet friction clutch of the coaxial twin-rotor helicopter tail rotor drive system has a certain influence on the stability of the entire tail drive system. According to the concentrated mass method, the multi-degree-of-freedom vibration differential equation of the multi-piece wet friction clutch model is established, as well as considering the unbalanced position of the clutch rotor in the rotational motion, the steel plates and friction plates are equivalent to spline pairs, the vibration displacement generated by the dynamic bonding process in the radial direction is analyzed, comparative analysis is carried out through experiments and theoretical simulations. The results show that both the equivalent dual steel plate and the equivalent friction plate will produce vibration displacement in the Y direction in the steady state, which is consistent with the assumption of clutch rotor imbalance. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
5. Reliability Evaluation of Distribution Network with Electric Vehicles and Distributed Generations Based on Network Equivalence and Sequential Monte Carlo Method.
- Author
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Wang, Haipeng, Li, Kaiwen, Liu, Zixuan, He, Yuling, Wang, Xiaolong, Sun, Kai, and Yang, Peng
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MONTE Carlo method , *ELECTRIC networks , *DISTRIBUTED power generation , *FAILURE analysis , *RELIABILITY in engineering , *ELECTRIC vehicles - Abstract
This paper proposes a reliability evaluation method of a distribution network with electric vehicles (EVs) and distributed generations (DGs) based on network equivalence and sequential Monte Carlo. Unlike traditional studies, the proposed method not only can effectively simplify the complexity structure of the distribution network with EVs and DGs, but also can establish a multidimensional reliability evaluation system for the distribution network with EVs and DGs. Firstly, the related models of DGs and EVs are established respectively in our study. Based on the minimum path method, the impact of each component fault on each load point is analyzed, and the failure impact analysis (FIA) table is constructed. Then, a simplified method for the structure of the distribution network with EVs and DGs based on network equivalence is proposed and validated. Moreover, the reliability evaluation method of the distribution network with EVs and DGs is given based on the sequential Monte Carlo. Finally, an illustrative example of the improved IEEE RBTS BUS6 F4 feeder system, as well as multiple dimensions discussions, are elaborated in detail to demonstrate the effectiveness and superiority of the proposed model. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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6. Climate change drove the route shift of the ancient Silk Road in two distinct ways.
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Wang, Haipeng, Chen, Jianhui, Qiu, Menghan, Shi, Zhilin, Zhang, Shengda, Dong, Guanghui, Ma, Shuai, Ai, Tao, Ren, Guan, and Chen, Fahu
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WATER shortages , *ANCIENT civilization , *HUMAN evolution , *CLIMATE change ,SILK Road ,TANG dynasty, China, 618-907 - Abstract
[Display omitted] A new high-quality chironomid-based temperature record was obtained from Shuanghu Lake in arid NW China. Combined with hydroclimatic and historical datasets, we demonstrated the direct effect (water shortages) and indirect effect (geopolitical conflicts) of climate change on the shift of the Silk Road route from the Tarim Basin to the northern slopes of the Tianshan Mountains during ∼420–850 CE. Although climate change has convincingly been linked to the evolution of human civilization on different temporal scales, its role in influencing the spatial patterns of ancient civilizations has rarely been investigated. The northward shift of the ancient Silk Road (SR) route from the Tarim Basin (TB) to the Junggar Basin during ∼420–850 CE provides the opportunity to investigate the relationship between climate change and the spatial evolution of human societies. Here, we use a new high-resolution chironomid-based temperature reconstruction from arid China, combined with hydroclimatic and historical datasets, to assess the possible effects of climate fluctuations on the shift of the ancient SR route. We found that a cooling/drying climate in the TB triggered the SR route shift during ∼420–600 CE. However, a warming/wetting climate during ∼600–850 CE did not inhibit this shift, but instead promoted it, because of the favorable climate-induced geopolitical conflicts between the Tubo Kingdom and the Tang Dynasty in the TB. Our findings reveal two distinct ways in which climate change drove the spatial evolution of human civilization, and they demonstrate the flexibility of societal responses to climate change. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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7. Metastable Liquid Properties and Surface Flow Patterns of Ultrahigh Temperature Alloys Explored in Outer Space.
- Author
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Wang, Haipeng, Hu, Liang, Xie, Wenjun, Chang, Jian, Zheng, Chenhui, Li, Mingxing, Wang, Qing, Liao, Hui, Liu, Dingnan, and Wei, Bingbo
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HIGH temperatures , *LIQUID surfaces , *OUTER space , *LIQUID alloys , *SURFACE waves (Fluids) , *BINARY metallic systems - Abstract
The metastable liquid properties and chemical bonds beyond 2000 K remain a huge challenge for ground‐based research on liquid materials chemistry. We show the strong undercooling capability, metastable liquid properties and surface wave patterns of refractory Nb−Si and Zr−V binary alloys explored in space environment. The floating droplet of Nb82.7Si17.3 eutectic alloy superheated up to 2338 K exhibited an extreme undercooling of 437 K, approaching the 0.2TE threshold for homogeneous nucleation of liquid‐solid reaction. The microgravity state endowed alloy droplets with nearly perfect sphericity and thus ensured the high accuracy to determine metastable undercooled liquid properties. A special kind of swirling flow was induced for liquid alloy owing to Marangoni convection, which resulted in the spiral microstructures on Zr64V36 alloy surface during liquid‐solid phase transition. The coupled impacts of surface nucleation and surface flow brought in a novel olivary shape for these binary alloys. Furthermore, the chemical bonds and atomic structures of high temperature liquids were revealed to understand the liquid properties in outer space circumstances. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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8. Metastable Liquid Properties and Surface Flow Patterns of Ultrahigh Temperature Alloys Explored in Outer Space.
- Author
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Wang, Haipeng, Hu, Liang, Xie, Wenjun, Chang, Jian, Zheng, Chenhui, Li, Mingxing, Wang, Qing, Liao, Hui, Liu, Dingnan, and Wei, Bingbo
- Subjects
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HIGH temperatures , *LIQUID surfaces , *OUTER space , *LIQUID alloys , *SURFACE waves (Fluids) , *BINARY metallic systems - Abstract
The metastable liquid properties and chemical bonds beyond 2000 K remain a huge challenge for ground‐based research on liquid materials chemistry. We show the strong undercooling capability, metastable liquid properties and surface wave patterns of refractory Nb−Si and Zr−V binary alloys explored in space environment. The floating droplet of Nb82.7Si17.3 eutectic alloy superheated up to 2338 K exhibited an extreme undercooling of 437 K, approaching the 0.2TE threshold for homogeneous nucleation of liquid‐solid reaction. The microgravity state endowed alloy droplets with nearly perfect sphericity and thus ensured the high accuracy to determine metastable undercooled liquid properties. A special kind of swirling flow was induced for liquid alloy owing to Marangoni convection, which resulted in the spiral microstructures on Zr64V36 alloy surface during liquid‐solid phase transition. The coupled impacts of surface nucleation and surface flow brought in a novel olivary shape for these binary alloys. Furthermore, the chemical bonds and atomic structures of high temperature liquids were revealed to understand the liquid properties in outer space circumstances. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. Spiral eutectic growth dynamics facilitated by space Marangoni convection and liquid surface wave.
- Author
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Wang, Haipeng, Liu, Dingnan, Zheng, Chenhui, Zhao, Jiongfei, Chang, Jian, Hu, Liang, Liao, Hui, Geng, Delu, Xie, Wenjun, and Wei, Bingbo
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SURFACE waves (Fluids) , *EUTECTICS , *HYPOEUTECTIC alloys , *LIQUID alloys , *EUTECTIC alloys , *MARANGONI effect , *NATURAL heat convection , *SURFACE waves (Seismic waves) - Abstract
Eutectic alloys display excellent application performances since the essential function of coupled microstructures is quite different from that of single-phase and peritectic alloys. However, due to the strong natural convection within liquid alloys under normal gravity, the eutectic growth process on earth usually produces traditional rod-like or lamellar composite microstructures, which hinders the exploration of distinctive coupled growth patterns. Here, we carried out the rapid solidification of hypoeutectic Zr64V36 alloy to explore novel coupled growth dynamics aboard the China Space Station under a long-term stable microgravity condition. An extreme liquid undercooling of 253 K was achieved for this refractory alloy, displaying a strong metastability in outer space. We find that a radial coupled pattern grew out of the nucleation site, accompanying a ripple-like surface microstructure. This resulted from the rapid eutectic growth within a highly undercooled alloy in combination with a liquid surface wave excited by the electrostatic field under microgravity. Especially, a spiral coupled growth mode occurred during radial eutectic growth and surface wave spreading, which were controlled by the Marangoni convection effect on the fluid flow pattern and eutectic growth dynamics. Our findings contribute to the coupled growth investigation by modulating gravity levels to develop multi-pattern microstructures. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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10. Opsin‐Free Activation of Bmp Receptors by a Femtosecond Laser.
- Author
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Xu, Manjun, Wang, Haipeng, Tian, Xiaoying, Li, Bingyi, Wang, Shaoyang, Zhao, Xiaohui, and He, Hao
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BONE morphogenetic proteins , *INFRARED lasers , *FEMTOSECOND lasers , *CELLULAR signal transduction , *FLAVINS , *STEM cells , *PHOTOACTIVATION - Abstract
Bone morphogenetic protein (BMP) signaling plays a vital role in differentiation, organogenesis, and various cell processes. As a member of TGF‐β superfamily, the BMP initiation usually accompanies crosstalk with other signaling pathways and simultaneously activates some of them. It is quite challenging to solely initiate an individual pathway. In this study, an opsin‐free optical method to specifically activate BMP receptors (BMPR) and subsequent pSmad1/5/8 cascades by a single‐time scan of a tightly‐focused femtosecond laser in the near infrared range is reported. Via transient two‐photon excitation to intrinsic local flavins near the cell membrane, the photoactivation drives conformational changes of preformed BMPR complexes to enable their bonding and phosphorylation of the GS domain in BMPR‐I by BMPR‐II. The pSmad1/5/8 signaling is initiated by this method, while p38 and pSmad2 are rarely perturbed. Based on a microscopic system, primary adipose‐derived stem cells in an area of 420 × 420 µm2 are photoactivated by a single‐time laser scanning for 1.5 s and exhibit pSmad1/5/8 upregulation and osteoblastic differentiation after 21 days. Hence, an opsin‐free, specific, and noninvasive optical method to initiate BMP signaling, easily accomplished by a two‐photon microscope system is reported. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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11. Boosting the photoelectrochemical performance of bismuth vanadate photoanode through homojunction construction.
- Author
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Wang, Haipeng, Wang, Shuyun, Oo, May Thawda, Yang, Yuewen, Zhou, Jiasheng, Huang, Miaoyan, and Zhang, Rui-Qin
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BISMUTH , *STANDARD hydrogen electrode , *PHOTOCATHODES , *ELECTRIC fields , *THIN films , *VANADATES , *SODIUM - Abstract
Construction of BVO ac -BVO al homojunction without incorporating other heteroatoms promoted an increase of photocurrent density to 3.6 mA/cm2 at 1.23 V vs. the reversible hydrogen electrode with 0.1 M sodium sulfite as the hole scavenger under the illumination. [Display omitted] The photoelectrochemical (PEC) performance of bismuth vanadate (BiVO 4) suffers from sluggish charge mobility and substantial charge recombination losses due to its intrinsic defect. To rectify the problem, we developed a novel approach to prepare an n - n + type II BVO ac -BVO al homojunction with staggered band alignment. This architecture involves a built-in electric field that facilitating the electron-hole separation at the BVO ac /BVO al interface. As a result, the BVO ac -BVO al homojunction shows superior photocurrent density up to 3.6 mA/cm2 at 1.23 V vs. reversible hydrogen electrode (RHE) with 0.1 M sodium sulfite as the hole scavenger, which is 3 times higher than that of the single-layer BiVO 4 photoanode. Unlike the previous efforts that modifying the PEC performance of BiVO 4 photoanodes through incorporating heteroatoms, the highly-efficient BVO ac -BVO al homojunction was achieved without incorporating any heteroatoms in this work. The remarkable PEC activity of the BVO ac -BVO al homojunction highlights the tremendous importance of reducing the charge recombination rate at the interface by constructing the homojunction and offers an effective strategy to form the heteroatoms-free BiVO 4 thin film as an efficient photoanode material for practical PEC applications. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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12. Temperature variations along the Silk Road over the past 2000 years: Integration and perspectives.
- Author
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Chen, Jianhui, Wang, Haipeng, Liu, Yan, Ma, Shuai, and Huang, Wei
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LITTLE Ice Age , *ICE cores , *TREE-rings , *ANCIENT civilization ,SILK Road ,HAN dynasty, China, 202 B.C.-220 A.D. - Abstract
Reconstructing temperature changes along the Silk Road (SR) over the last two millennia can provide insights into past global changes and their impact on the rise and fall of ancient civilizations in this region. Numerous high-quality single-site paleotemperature records have been produced for the eastern part of the SR (mainly for the Xinjiang region and its surrounding areas), which provide the data basis for a comprehensive synthesis. In this study, we used objective criteria to select 10 high-quality ones from 30 temperature reconstructions derived from various geological archives including lacustrine sediments, ice cores, and tree rings in this region. Our aims are to summarize the pattern of temperature change over the past 2000 years, to provide a long-term viewpoint on the present warming, and to evaluate the impact of climate change on civilizations along the SR. The principal results are as follows: (1) The temperature variations over the last millennium are mutually consistent within these records. The study area experienced typical climate anomalies during the Medieval Warm Period (MWP, AD 1000–1250), the Little Ice Age (LIA, AD 1450–1850), and the Current Warm Period (CWP, AD 1850 to present); however, contrary to previous knowledge, the amplitude of climatic warming during the CWP did not exceed that during the MWP. (2) Fewer temperature records were available for the interval AD 1–1000, and there were large differences between them. For example, the reconstructed climate during both the Han Dynasty and the Sui-Tang Dynasties was either warm or cold, without prevailing consensus. (3) The warming during the MWP favored the rapid development of the SR route along the northern slopes of the Tianshan Mountains, and the cooling during the LIA contributed to the decline of the SR marked by the closure of the Jiayuguan Pass. Notably, the scarcity of temperature records and the discrepancies between them during AD 1–1000 in the eastern part of the SR have hindered our understanding of the hydroclimatic changes and their influence on the development of civilizations along the SR. Thus, it is important to obtain an increased number of high-quality reliable records spanning the past 2000 year, and to examine the occurrence of local signals of temperature changes during the period of AD 1–1000. On the other hand, the paleotemperature investigation on the western part of the SR over the last two millennia is wholly insufficient, and thus more high-quality single-site and integrated studies are needed, to facilitate more comprehensive insights into the coupled relationship between climate change and the rise and fall of civilizations along the entire length of the Silk Road. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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13. Hydrochloric acid etching induced flower-like NiFe-layered double hydroxide as efficient electrocatalyst for oxygen evolution reaction.
- Author
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Wang, Shuyun, Wang, Haipeng, Chen, Shengmei, Cheung, Ka Kiu Keith, Wong, Hon Fai, Leung, Chi Wah, and Zapien, Juan Antonio
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OXYGEN evolution reactions , *HYDROCHLORIC acid , *IRON-nickel alloys , *ETCHING , *HYDROXIDES , *CHARGE transfer , *CLEAN energy - Abstract
To meet the increasing demand for clean energy storage in modern society, the development of efficient and low-cost electrocatalysts that can overcome and accelerate the sluggish kinetics of electrochemical reactions is required. NiFe-Layered Double Hydroxide (NiFe-LDH) is regarded as an effective oxygen evolution reaction (OER) electrocatalyst, but most of the current synthesis methods, such as electrochemical deposition and calcination, are complex and difficult to operate on a large scale. Herein, we report the preparation of NiFe-LDH directly on a NiFe foam substrate using a simple two-step method in which the surface oxide layer is first removed from NiFe foam using a room-temperature hydrochloric acid bath for 10 min, followed by soaking in hydrochloric acid solution at 80 °C for 20 h. The prepared NiFe foam etched by hydrochloric acid for 20 h (NiFe-20-H) exhibited a unique hydrangea flower-like structure with a large surface area and abundant active sites, which is favorable for OER. Combining the structural advantages of large number of exposed active sites, synergistic effects of nickel and iron, and the convenient charge transfer path provided by the NiFe foam, the resulting NiFe-20-H sample achieved a current density of 10 mA cm−2 at an extremely low overpotential (241 mV) and a small Tafel slope of 44.2 mV dec−1, providing excellent long-term stability in alkaline electrolyte, surpassing pristine NiFe foam reported in our work, as well as many state-of-the-art electrocatalysts and IrO 2. This efficient synthesis of NiFe-LDH provides a new approach for the development of non-noble OER electrocatalysts and has wide application prospects in the field of electrocatalysts. [Display omitted] • NiFe-LDH with flower-like structure was designed by a simple two-step hydrochloric acid treatment. • The existence of NiFe-LDH was proved by a series of qualitative and quantitative characterization methods. • NiFe-20-H has excellent electrocatalytic performance for oxygen evolution reaction. • The reason for the outstanding OER performance of NiFe-20-H is discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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14. Fitness-Based Hierarchical Reinforcement Learning for Multi-human-robot Task Allocation in Complex Terrain Conditions.
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Wang, Haipeng, Li, Shiqi, and Ji, Hechao
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MACHINE learning , *BIOLOGICAL fitness , *REINFORCEMENT learning - Abstract
A fitness-based hierarchical reinforcement learning method is proposed in this study for multi-human-robot task allocation in complex terrain conditions. Firstly, three fitness functions, including task fitness, distance fitness, and environmental fitness, are designed to quantify the adaptability of each subject to each task. Then, a two-layer hierarchical reinforcement learning algorithm is designed for task allocation. The values of the fitnesses are used as input for the task allocation algorithm. A series of task allocation experiments are conducted to verify the effectiveness of the proposed methods. Compared with the conventional reinforcement learning algorithm, the task allocation efficiency increases by no less than 57% by the proposed method under different numbers of subjects, and by about 65% under different numbers of tasks. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
15. Economic Dispatch Optimization of a Microgrid with Wind–Photovoltaic-Load-Storage in Multiple Scenarios.
- Author
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Wang, Haipeng, Wu, Xuewei, Sun, Kai, Du, Xiaodong, He, Yuling, and Li, Kaiwen
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MICROGRIDS , *PARTICLE swarm optimization , *RENEWABLE energy costs , *POWER (Social sciences) , *POWER resources , *ENERGY consumption - Abstract
The optimal economic power dispatching of a microgrid is an important part of the new power system optimization, which is of great significance to reduce energy consumption and environmental pollution. The microgrid should not only meet the basic demand of power supply but also improve the economic benefit. Considering the generation cost, the discharge cost, the power purchase cost, the electricity sales revenue, the battery charging and discharging power constraints, and the charging and discharging time constraints, a joint optimization model for a multi-scenario microgrid with wind–photovoltaic-load storage is proposed in our study. Additionally, the corresponding model solving algorithm based on particle swarm optimization is also given. In addition, taking the Wangjiazhai project in Baiyangdian region as a case study, the effectiveness of the proposed model and algorithm is verified. The joint optimization model for a microgrid with wind–photovoltaic-load storage in multiple scenarios is discussed and investigated, and the optimal economic power dispatching schemes in multiple scenarios are also provided. Our research shows that: (1) the battery can play a role in peak shaving and valley filling, which can make microgrids more economical; (2) when the power purchase price is lower than the cost of renewable energy power generation, if the wind turbine and the photovoltaics are allowed to be discarded the microgrid will produce higher economic benefits; and (3) restricting the exchange power between the microgrid and the main power network will lead to a negative impact on the economy for the microgrid. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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16. Laser Joining of Continuous Carbon Fiber-Reinforced PEEK and Titanium Alloy with High Strength.
- Author
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Wang, Haipeng, Ren, Zhongjing, and Guan, Yingchun
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TITANIUM alloys , *METALLIC composites , *CARBON composites , *TITANIUM composites , *FRACTURE strength , *AUTOMOTIVE engineering , *AEROSPACE engineering , *CARBON fibers - Abstract
The generation of high-performance heterojunctions between high-strength resin matrix composites and metals is of great significance for lightweight applications in fields such as aerospace and automobile engineering. Herein, we explored the feasibility of employing a laser joining process to achieve high-strength heterojunctions between continuous carbon fiber-reinforced PEEK (CCF30/PEEK) composites and titanium alloy (Ti6Al4V). A joint strength of over 50 MPa was achieved through constructing mechanical interlocking structures between CCF30/PEEK and Ti6Al4V. Tensile tests revealed that the fracture of joints was mainly ascribed to the detachment of carbon fibers from the resin matrix and the breakage of carbon fibers. The structures with different orientations and dimensions were confirmed to significantly influence the formation of interlocking structures near the joining interface and the resultant fracture strength of joints. It is believed that the results presented in this study provide a strong foundation for the production of high-performance heterojunctions. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
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17. Research on the Optimal Economic Power Dispatching of a Multi-Microgrid Cooperative Operation.
- Author
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Wang, Haipeng, Wu, Xuewei, Sun, Kai, and He, Yuling
- Subjects
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POWER (Social sciences) , *ECONOMIC research , *PARTICLE swarm optimization , *ENVIRONMENTAL economics , *ECONOMIC models - Abstract
The economic power-dispatching model of a multi-microgrid is comprehensively established in this paper, considering many factors, such as generation cost, discharge cost, power-purchase cost, power sales revenue, and environmental cost. To construct this model, power interactions between the two microgrids and those between the micro- and main grids are considered. Furthermore, the particle swarm optimization (PSO) algorithm is utilized to solve the economic power-dispatching model. To validate the effectiveness of the proposed model as well as the solution algorithm, a practical project case is studied and discussed. In the case study, the impact of multiple scenarios is first analyzed. Then, the system operation economic costs under different scenarios are described in detail. Moreover, according to the optimization power-dispatching results of the multi-microgrid, power interactions between the two microgrids and those between the micro- and main grids are fully discussed. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
18. Energy-Delay Minimization of Task Migration Based on Game Theory in MEC-Assisted Vehicular Networks.
- Author
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Wang, Haipeng, Lv, Tiejun, Lin, Zhipeng, and Zeng, Jie
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GAME theory , *NASH equilibrium , *EQUILIBRIUM , *TASKS , *HEURISTIC algorithms - Abstract
Roadside units (RSUs), which have strong computing capability and are close to vehicle nodes, have been widely used to process delay- and computation-intensive tasks of vehicle nodes. However, due to their high mobility, vehicles may drive out of the coverage of RSUs before receiving the task processing results. In this paper, we propose a mobile edge computing-assisted vehicular network, where vehicles can offload their tasks to a nearby vehicle via a vehicle-to-vehicle (V2V) link or a nearby RSU via a vehicle-to-infrastructure link. These tasks are also migrated by a V2V link or an infrastructure-to-infrastructure (I2I) link to avoid the scenario where the vehicles cannot receive the processed task from the RSUs. Considering mutual interference from the same link of offloading tasks and migrating tasks, we construct a vehicle offloading decision-based game to minimize the computation overhead. We prove that the game can always achieve Nash equilibrium and convergence by exploiting the finite improvement property. We then propose a task migration (TM) algorithm that includes three task-processing methods and two task-migration methods. Based on the TM algorithm, computation overhead minimization offloading (COMO) algorithm is presented. Extensive simulation results show that the proposed TM and COMO algorithms reduce the computation overhead and increase the success rate of task processing. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
19. Research on non-intrusive load decomposition model based on parallel multi-scale attention mechanism and its application in smart grid.
- Author
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Pan, Guobing, Wang, Haipeng, Tian, Tao, Luo, Yuhan, Xia, Songdi, and Li, Qiyu
- Abstract
This paper presents the MUSENILM model, a non-intrusive load decomposition model incorporating a parallel multi-scale attention mechanism to enhance energy monitoring and management in smart grids. The core innovation of the proposed model is its ability to extract multi-scale features, enhancing the model's understanding of time series data and achieving significant performance improvements on the UK-DALE and REDD public datasets. Specifically, when MUSENILM identifies the fridge electricity consumption pattern on the UK-DALE public dataset, compared to previous models, the accuracy improves from 88% to 91%, and the F1 score increases from 87% to 90%; on the load decomposition tasks of the remaining four appliances, the F1 scores are all improved, while the mean absolute error (MAE) and cumulative absolute error (SAE) for the five appliances are also reduced. Additionally, it shows better results compared to previous models on the REDD dataset. Moreover, when the MUSENILM model is transplanted to embedded devices and applied in smart grids, it can effectively identify illegal lithium battery charging events of electric bicycles in different scenarios, which is crucial for ensuring grid security and optimizing energy distribution. This research not only provides an efficient method for the field of NILM but also offers practical solutions for violation monitoring and management in smart grids. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
20. Ice growth inhibition by poly(vinyl alcohol): Insights from near-infrared spectroscopy and molecular dynamics simulation.
- Author
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Su, Changlin, Wang, Haipeng, Cai, Wensheng, and Shao, Xueguang
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MOLECULAR spectroscopy , *MOLECULAR dynamics , *NEAR infrared spectroscopy , *ICE , *CRYSTAL lattices , *ICE crystals - Abstract
The near-infrared spectra of PVA solutions during the ice growth process were presented, and the WPT method was employed to enhance spectral resolution. In the high-resolution spectra, two new peaks emerged at 6767 and 6661 cm−1, with their intensity increasing as the ice grows. These two peaks related to OH groups in PVA forming one and two hydrogen bonds with water molecules, respectively. Validation was conducted through MD simulations. [Display omitted] • NIR spectroscopy combined with MD simulations is use for studying the interactions between PVA and ice. • Wavelet Package Transform was used to enhance the resolution of the spectra. • OH groups of PVA bind to like-ice molecules through one or two hydrogen bond(s). • CH 2 groups play an important role in the ice-growth inhibition of PVA. • There is a collaborative effect between CH 2 and OH groups during the ice-growth inhibition of PVA. Poly(vinyl alcohol) (PVA) is a well-known ice recrystallization inhibitor, yet its antifreeze mechanism remains debated. Here, the mechanism of PVA is elucidated by means of near-infrared spectroscopy and molecular dynamics (MD) simulations. Analysis of the spectra of PVA solutions during the ice growth process reveals a dynamic interaction conversion from PVA-water to PVA-ice, indicating that PVA inhibits ice growth by directly binding to ice. Moreover, we observed OH binding to the ice surface through one or two hydrogen bonds but did not witness the previously reported formation of three hydrogen bonds when the OH group perfectly embeds into the ice crystal lattice. In addition, the spectral feature of CH 2 groups of PVA indirectly indicates their significant contribution to inhibiting ice growth through hydrophobic interactions. The MD simulations further confirm the effective roles of both OH and CH 2 groups for inhibiting ice growth. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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21. Molecular characterization, expression and anti-tumor function analysis of yak IFITM2 gene.
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Wang, Haipeng, Wang, Li, Luo, Xiaolin, Guan, Jiuqiang, Zhang, Xiangfei, Zhang, Ling, and Xiang, Yi
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YAK , *MEMBRANE proteins , *BAX protein , *MOLECULAR cloning , *B cells , *PROTEIN expression , *CELL migration - Abstract
IFITM2 is interferon-induced transmembrane protein 2, which plays an extremely key role in anti-tumor and anti-virus diseases. In this study, the 602 bp cDNA sequence of the yak (Bos grunniens) IFITM2 (BgIFITM 2) gene was obtained. Moreover, the prokaryotic expression vector of BgIFITM2 protein was constructed and expressed successfully, with a molecular weight of 33.680 kDa. The proliferation activities and migration abilities of HepG2 cells were significantly inhibited after treatment with BgIFITM2 protein (0.1 and 1 μg/mL) (P < 0.05). The expressions of B cell lymphoma-2 (BCL 2)/BCL2-associated X (BAX) and molecular target of rapamycin (mTOR) genes were significantly decreased, but the expressions of BAX gene were significantly increased after treatment with BgIFITM2 protein (0.1 and 1 μg/mL) (P < 0.05). The expression of BAX protein was also significantly increased after treatment with 1 μg/mL BgIFITM2 protein (P < 0.05). Finally, the addition of BgIFITM2 protein attenuated the formation of tumor lesions in mice, and the pathological damage of the lung was less than that in the model group. The expression of Ki67 protein in the model group was significantly higher than that in the control group (P < 0.05), but the expression of Ki67 protein in the BgIFITM2 group was significantly lower than that in the model group (P < 0.05). Taken together, BgIFITM2 protein could inhibit the proliferative activity of HepG2 cells by regulating apoptosis-related genes, and reduce the invasiveness of HepG2 cells in mice lung tissue. These results facilitate further studies on the function of BgIFITM2 protein. • The yak (Bos grunniens) IFITM 2 (BgIFITM 2) gene was cloned and bioinformatics analysis. • BgIFITM2 protein could inhibit the proliferations of HepG2 cells by regulated the apoptosis-related genes. • BgIFITM2 protein can reduce the invasiveness of cancer cells to lung tissue in mice. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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22. Corrigendum to "Research on non-intrusive load decomposition model based on parallel multi-scale attention mechanism and its application in smart grid" [Energy Build. 312 (2024) 114210].
- Author
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Pan, Guobing, Wang, Haipeng, Tian, Tao, Luo, Yuhan, Xia, Songdi, and Li, Qiyu
- Published
- 2024
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23. A 17 ka multi‐proxy paleoclimatic record on the northeastern Tibetan Plateau: implications for the northernmost boundary of the Asian summer monsoon during the Holocene.
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Wang, Haipeng, Hu, Yu, Zhang, Xu, Lv, Feiya, Ma, Xueyang, Wu, Duo, Chen, Fahu, Zhou, Aifeng, Hou, Juzhi, and Chen, Jianhui
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HOLOCENE Epoch , *WATERSHEDS , *YOUNGER Dryas , *GLACIAL melting , *LAKE sediments , *MONSOONS , *CHEMICAL weathering - Abstract
Knowledge of the paleoclimatic record of the northeastern Tibetan Plateau (NETP) can potentially improve our understanding of the evolution of the Asian summer monsoon (ASM). However, the history of climate change and inferred spatial extent of the ASM on the NETP since the last deglaciation remain unclear. Here, we use several environmental proxies from the sediments of Hala Lake (beyond the modern limit of ASM), including chironomids, loss‐on‐ignition, grain size and element data, to explore the climatic history of the NETP and the northern boundary of the ASM since the last deglaciation. The results document a series of climatic events during the deglaciation, including Heinrich Event 1, the Bølling–Allerød interstadial and the Younger Dryas event. The records also reveal the timing of the megathermal and precipitation maximum, the lake‐level maximum, and strongest chemical weathering, which occurred during ~10–7 ka. The inferred precipitation maximum during the early Holocene in the Hala Lake basin, which can be verified by the simulated precipitation change, is consistent with that in typical Indian summer monsoon (ISM) regions, suggesting that the ISM has penetrated into Hala Lake basin at that time. The monsoon‐dominated climate in the Hala Lake basin during the early Holocene and the westerlies‐dominated climate in the arid central Asia indicate that the maximum areal extent of the ASM on the NETP since the last deglaciation lay to the northwest of Hala Lake basin. In combination with other published records, the northernmost boundary of the ASM over China since the last deglaciation has been tentatively delineated, to shed some lights on this long‐standing debate. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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24. Molecular characterization, expression and functional analysis of yak IFITM3 gene.
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Wang, Haipeng, Wang, Li, Li, Juan, Fu, Fang, Zheng, Yao, and Zhang, Ling
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YAK , *FUNCTIONAL analysis , *IMMOBILIZED proteins , *MOLECULAR weights , *SPLEEN - Abstract
IFITM3 is interferon-induced transmembrane 3, which plays an extremely key role in anti-proliferation, anti-virus and anti-tumor diseases. In this study, the yak (Bos grunniens) IFITM 3 (BgIFITM 3) gene contained a 5′-untranslated region (UTR) (25 bp), a coding region (441 bp), and a 3′-UTR (115 bp). The expression of BgIFITM 3 gene in liver was significantly higher than that in heart, spleen, lung and kidney (P < 0.01). BgIFITM3 protein was localized on the yak hepatocyte plasma membrane, and its expression was significantly different between 1 day and 15 months of age (P < 0.05). Moreover, the prokaryotic expression vector of BgIFITM3 protein was constructed and expressed successfully, with a molecular weight of 19.5 kDa. The activities of yak hepatocyte were significantly inhibited after treating with BgIFITM3 protein (10 and 20 μg/mL) (P < 0.01). The expression levels of ERBB -2, IRS -1, PI 3 KR -1, AKT -1 and MAPK -3 were significantly lower after treating with 20 μg/mL BgIFITM3 protein (P < 0.05). Besides, the activities of HepG2 cells were significantly inhibited after treating with BgIFITM3 protein (1, 10 and 20 μg/mL) (P < 0.05). While, the cloning ability and migration ability of HepG2 cells were significantly inhibited after treating with 10 μg/mL BgIFITM3 protein (P < 0.05). Finally, the mitochondria of HepG2 cells was concentrated, cristae widened, and the double film density of mitochondria was increased after treating with 10 μg/mL BgIFITM3 protein. After 10 μg/mL BgIFITM3 protein treating, the expression levels of VDAC -2, VDAC -3 and p 53 genes were significantly increased, but the expression level of GPX -4 gene was significantly decreased (P < 0.01). Taken together, the BgIFITM3 protein could inhibit the proliferations of yak hepatocyte and HepG2 cells by regulating the PI3K/Akt pathway or ferroptosis-related genes, respectively. These results benefit for further study of the function of BgIFITM3 protein. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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25. The synthesis of greenish phosphorus on carbon substrates.
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Wang, Haipeng, Liu, Cheng, Wang, Huili, Han, Xinpeng, Zhang, Shaojie, Sun, Jiantong, Zhang, Yiming, Cao, Yu, Yao, Yuan, and Sun, Jie
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CHEMICAL vapor deposition , *PHOSPHORUS , *PARTIAL pressure , *CARBON paper , *VAPOR pressure , *CHEMICAL properties - Abstract
A phosphorus allotrope called greenish phosphorus was successfully synthesized via a simple chemical vapor deposition method. We revealed that the critical factors in the formation mechanism of greenish phosphorus are the partial pressure of the phosphorus vapor and the structure of the substrate. On the substrates of a glassy carbon wafer and carbon paper, the edge carbon structure can activate P4 molecules, allowing them to polymerize due to strong adsorption (Ead = −1.62 eV). Greenish phosphorus possesses a distinct crystal structure, different from red phosphorus and black phosphorus, thus leading to unique physical and chemical properties, and potential applications in optical, electrical, and magnetic fields. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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26. The effect of workplace violence on depression among medical staff in China: the mediating role of interpersonal distrust.
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Wang, Haipeng, Zhang, Yuxia, and Sun, Long
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VIOLENCE in the workplace , *MEDICAL personnel , *HOSPITAL medical staff , *SUSPICION , *OCCUPATIONAL health services - Abstract
Objective: Workplace violence has been recognized globally as a serious occupational hazard in health service occupations, and existing studies have identified that workplace violence can significantly lead to depression. Interpersonal distrust, an important topic, has also been proved associated with workplace violence and depression. However, the mediating effect of interpersonal distrust has not been tested before. Results of such testing can help us to understand further the effect mechanism of workplace violence on depression. Methods: In the current study, we collected 3426 valid questionnaires based on a cross-sectional design distributed among medical staff in Chinese hospitals. Depression, workplace violence, interpersonal distrust, social support, physical diseases, and some other social-demographic variables were evaluated. SPSS macros program (PROCESS v3.3) was used to test the mediating effect of interpersonal distrust on the association between workplace violence and depression. Results: The data analyzed in the current study demonstrated that 52.2% of medical staff had experienced workplace violence before. Experiencing verbal violence (β = 2.99, p < 0.001), experiencing physical violence (β = 3.70, p < 0.01), experiencing both kinds of violence (β = 4.84, p < 0.001), high levels of interpersonal distrust (β = 0.22, p < 0.001), working as a nurse (β = 1.10, p < 0.05), working as a manager (β = − 1.72, p < 0.001), suffering physical disease (β = 3.35, p < 0.001), and receiving social support (β = − 0.23, p < 0.001) were significantly associated with depression. Workplace violence had not only positive direct effects on depression, but also an indirect effect on depression through interpersonal distrust as a mediator. Conclusion: Interpersonal distrust can mediate the association between workplace violence and depression. Increasing interpersonal trust or reducing workplace violence would be beneficial to promoting mental health status among medical staff. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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27. Understanding the Profiles of Blood Glucose Monitoring Among Patients with Type 2 Diabetes Mellitus: A Cross-Sectional Study in Shandong, China.
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Yao, Jiansen, Wang, Haipeng, Yan, Jingjing, Shao, Di, Sun, Qiang, and Yin, Xiao
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BLOOD sugar monitoring , *TYPE 2 diabetes , *PATIENT monitoring , *SELF-monitoring (Psychology) , *BLOOD groups , *CLINICAL trials monitoring - Abstract
Background: Blood glucose monitoring is essential in diabetic care and management. Monitoring using glucometers in home and in laboratories by professionals in certain health institutes were the common methods of blood glucose monitoring in clinical practice. This study aimed to characterize the profiles of blood glucose monitoring in the view of the discrepancy in methods and frequency conducted by the patients with type 2 diabetes mellitus (T2DM) in China, and to explore factors influencing the profiles. Methods: A cross-sectional, community-based study was conducted in Shandong province, China, with a multi-stage stratified sampling. A total of 2166 T2DM patients completed the structured questionnaires about the real-world status of blood glucose monitoring and other questions composed of demographic and clinical characteristic as well as the diabetes-related cognitive scales. Latent profile analysis (LPA) was used to identify the underlying profiles of blood glucose monitoring based on self-reported frequency of blood glucose monitoring through different methods. Univariate and multivariate logistic regression were used to analyze the characteristics of the profiles and to explore the factors associated with it. Results: Among the 2166 participants, the mean frequency of blood glucose monitoring was 2.77 times (standard deviation: 7.67) per month. LPA indicated that five-class model was the best solution for classifying the latent groups of blood glucose monitoring: Class 1 "Low frequency in all", Class 2 "High frequency in hospitals", Class 3 "High frequency in primary health institutes", Class 4 "High frequency in pharmacies", and Class 5 "High frequency in self-monitoring". The proportions of the patients in class 1, class 2, class 3, class 4, and class 5 were 88.1% (n=1909), 1.3% (n=28), 3.1% (n=67), 6.1% (n=133) and 1.3% (n=29), respectively. Multivariate logistic regression showed that participants who had higher income (OR: 1.58, 95% CI: 1.04∼ 2.41, p< 0.05), had diabetes complication(s) (OR=1.37, 95% CI: 1.03∼ 1.02, p=0.03) and had a good knowledge of blood glucose control (OR=1.59, 95% CI: 1.17∼ 2.16, p< 0.01) were more likely to have high frequency of blood glucose monitoring (in class 2, 3, 4, 5), and the rural patients were less likely to had high frequency of blood glucose monitoring (OR=0.47, 95% CI: 0.35∼ 0.63, p< 0.01). Conclusion: Low frequency dominates the characteristics of the profiles of blood glucose monitoring among T2DM patients in China, though distinct blood glucose monitoring groups can be identified by LPA. Educational and financial supports were recommended to increase the frequency of blood glucose monitoring in patients with T2DM, focusing on the patients with low socioeconomic status. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
28. Capacitive proximity skin for non-contact liquid state measurement of robot grippers with different structures.
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Wang, Haipeng, Wang, Zhiguo, Zhu, Gancheng, and Zhang, Shuai
- Subjects
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PROXIMITY detectors , *ROBOT control systems , *ROBOTS , *CAPACITIVE sensors , *LIQUIDS , *ROBOT hands - Abstract
Handling liquid-filled containers is a frequently encountered yet challenging task for robotics. In this paper, a novel capacitive proximity skin was developed to measure liquid levels before grasping, improving the performance of robotics in application areas like domestic service, manufacturing, healthcare, and food processing. This capacitive proximity skin features a flexible structure that is readily adaptable to a variety of grippers, and it seamlessly integrates with Robot Operating System (ROS)-based control systems. Experiments were performed to compare this proximity skin against non-flexible capacitive proximity sensors, focusing on detection frequency and working distance. The results showed that the capacitive proximity skin achieved data-lossless detection in 0.08 s (12.5 Hz) and contactless measurement of liquid level within 0.7 cm, making it highly suitable for grasping operations. This capacitive proximity skin offers as a versatile solution for robotic applications that involve unsealed liquid-filled containers, and it has the potential for application across a wide range of industries. [Display omitted] • Prototyped non-contact liquid measurement system with flexible electrodes for ROS-based robot control. • Developed modularized capacitive proximity skin solutions for various gripper types. • Created capacitive proximity skin grippers for pre-grasping liquid measurements. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
29. FTransCNN: Fusing Transformer and a CNN based on fuzzy logic for uncertain medical image segmentation.
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Ding, Weiping, Wang, Haipeng, Huang, Jiashuang, Ju, Hengrong, Geng, Yu, Lin, Chin-Teng, and Pedrycz, Witold
- Subjects
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CONVOLUTIONAL neural networks , *IMAGE segmentation , *MEDICAL logic , *FUZZY logic , *DIAGNOSTIC imaging , *FUZZY integrals , *IMAGE fusion - Abstract
The accurate segmentation of medical images plays a crucial role in diagnosing and treating diseases. Although many methods now use multimodal joint segmentation, the joint use of segmentation features extracted by multiple models can lead to heterogeneity and uncertainty. Unreasonable fusion methods cannot exploit the advantages of multiple models and still lack good performance in segmentation. Therefore, this study proposes the FTransCNN model, which is composed of a convolutional neural network (CNN) and Transformer and is based on a fuzzy fusion strategy that jointly utilizes the features extracted by a CNN and Transformer through a new fuzzy fusion module. First, the CNN and Transformer act as the backbone network for parallel feature extraction. Second, channel attention is used to promote the global key information of Transformer to improve the feature representation ability, and spatial attention is used to enhance the local details of CNN features and suppress irrelevant regions. Third, the proposed model applies the Hadamard product to model fine-grained interactions between the two branches and uses the Choquet fuzzy integral to suppress heterogeneity and uncertainty in fused features. Fourth, FTransCNN employs fuzzy attention fusion module (FAFM) hierarchical upsampling to effectively capture both low-level spatial features and high-level semantic context. Finally, the new model obtains the final segmentation result by using the deconvolution and results in an improvement in segmentation. The experimental results on Chest X-ray and Kvasir-SEG dataset show that FTransCNN has better performance on segmentation tasks than the-state-of-the-art deep segmentation models. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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30. Online detection of anomaly behaviors based on multidimensional trajectories.
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Pan, Xinlong, Wang, Haipeng, Cheng, Xueqi, Peng, Xuan, and He, You
- Subjects
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ANOMALY detection (Computer security) , *NEAREST neighbor analysis (Statistics) , *INFORMATION overload , *SEQUENTIAL learning , *FALSE alarms , *PREDICTION theory - Abstract
• Sequential multi-factor hausdorff nearest neighbor conformal anomaly detector (SMFHNN CAD) is proposed. • Inductive conformal anomaly detector is constructed. • Sequential multi-factor hausdorff nearest neighbor inductive conformal anomaly detector (SMFHNN ICAD) is proposed. • The performance of the proposed algorithm is investigated. In the surveillance domain, timely detection of anomaly behaviors is very important and is a great challenge to human operators due to information overload, fatigue and inattention. Many anomaly detection algorithms based on trajectories have been proposed for this problem. However, these algorithms generally have problems such as complex parameter setting, unfaithful statistical model, not well-calibrated false alarm rate, poor ability of online learning and sequential anomaly detection, etc. The theory of conformal prediction was introduced to solve these problems by constructing the sequential Hausdorff nearest neighbor conformal anomaly detector. Yet, it only considers position information of the targets and is not sensitive to velocity and course anomaly behaviors. And the run times are increasing as the increase of the data size, which is not appropriate for early warning surveillance application. In order to solve these problems, sequential multi-factor Hausdorff nearest neighbor conformal anomaly detector (SMFHNN CAD) and sequential multi-factor Hausdorff nearest neighbor inductive conformal anomaly detector (SMFHNN ICAD) based on multidimensional trajectories are proposed in this paper. Experiments in both simulated military scenario and realistic civilian scenario show the presented algorithm has a good performance to online detect anomaly behaviors and would have a wide prospect in early warning surveillance systems. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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31. Factors associated with the utilization of community-based diabetes management care: A cross-sectional study in Shandong Province, China.
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Yao, Jingjing, Wang, Haipeng, Yin, Jia, Shao, Di, Guo, Xiaolei, Sun, Qiang, and Yin, Xiao
- Subjects
- *
HEALTH care reform , *DIABETES , *HEALTH facilities , *MEDICAL personnel , *RURAL-urban differences , *CROSS-sectional method , *COMMUNITY health services , *MEDICAL care , *PATIENTS' attitudes , *TYPE 2 diabetes , *SELF-efficacy , *RESEARCH funding , *LOGISTIC regression analysis , *RURAL population - Abstract
Background: Community-based diabetes management is known to be an important strategy for global diabetes control. In China, community-based diabetes management care, including regular blood glucose tests and guidance on medicine use, dietary control, and physical exercise provided by primary health institutions (PHIs), as one of the key contents of the national essential public health services (EPHS), was implemented since 2009 when the new round of health system reform was initiated. This study aimed to investigate the utilization of community-based diabetes management care services, and explore the factors influencing utilization from both patients' and providers' points of view.Methods: In total, 2520 type-2 diabetes mellitus (DM) patients registered for EPHS were selected from 63 PHIs in eight counties of Shandong province, China, using multi-stage stratified sampling. Of those, 2166 patients (response rate: 85.4%) completed face-to-face structured questionnaires on their utilization of community-based diabetes management care services. Further, 63 PHIs were surveyed on diabetes care delivery, and 444 primary healthcare providers were purposively sampled from those PHIs to measure their knowledge of diabetes management care delivery, using a self-developed questionnaire. Descriptive statistics were used to analyze the delivery and utilization of diabetes management care services. Multilevel logistic regression models were used to analyze the factors associated with patients' utilization of diabetes management services.Results: All 63 PHIs reported that all the required four diabetes management services were provided through EPHS. However, only 49.6% of the patients reported they fully used these services, with no statistically significant difference between urban and rural patients. Patients who had higher knowledge of diabetes and better self-efficacy in controlling the condition, were more likely to fully utilize diabetes management care. A larger number of PHI health staff per 1000 population was associated with better utilization of care.Conclusion: Although community-based diabetes management services are well available to Chinese DM patients under the framework of EPHS, the actual utilization of diabetes management services among the patients was poor. The size of the PHI workforce, patients' knowledge and self-efficacy in controlling diabetes, were important predictors of utilization, and could be enhanced to improve control of diabetes. [ABSTRACT FROM AUTHOR]- Published
- 2020
- Full Text
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32. Job satisfaction, burnout, and turnover intention among primary care providers in rural China: results from structural equation modeling.
- Author
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Wang, Haipeng, Jin, Yinzi, Wang, Dan, Zhao, Shichao, Sang, Xingang, and Yuan, Beibei
- Subjects
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PSYCHOLOGICAL burnout , *CLUSTER analysis (Statistics) , *STATISTICAL correlation , *DEPERSONALIZATION , *EMOTIONS , *JOB satisfaction , *LABOR turnover , *MEDICAL personnel , *PRIMARY health care , *QUESTIONNAIRES , *REWARD (Psychology) , *RURAL health , *STATISTICAL sampling , *SCALE analysis (Psychology) , *SURVEYS , *WORK environment , *MULTIPLE regression analysis , *STRUCTURAL equation modeling , *CROSS-sectional method - Abstract
Background: Low job satisfaction, severe burnout and high turnover intention are found to be prevalent among the primary care providers (PCPs) in township health centers (THCs), but their associations have received scant attention in the literature. In light of this, this study aims to examine the relationships between job satisfaction, burnout and turnover intention, and explore the predictors of turnover intention with a view to retaining PCPs in rural China. Methods: Using the multistage cluster sampling method, a cross-sectional survey was conducted in Shandong Province, China. 1148 PCPs from 47 THCs participated in this study. Job satisfaction, burnout and turnover intention were measured with a multifaceted instrument developed based on the existing literature, the Maslach Burnout Inventory and the participants' responses to a Likert item drawn from the literature, respectively. The relationships of the three factors were examined using Pearson correlation and structural equation modeling, while the predictors of turnover intention were investigated using multivariate logistic regression. Results: The subscale that the PCPs were most dissatisfied with was job rewards (95.12%), followed by working environment (49.65%) and organizational management (47.98%). The percentages of the PCPs reporting high-levels of emotional exhaustion, depersonalization and reduced personal accomplishment were 27.66, 6.06, and 38.74%, respectively. About 14.06% of the respondents had high turnover intention. There was a significant direct effect of job satisfaction on burnout (γ = − 0.52) and turnover intention (γ = − 0.29), a significant direct effect of burnout on turnover intention (γ = 0.28), and a significant indirect effect (γ = − 0.14) of job satisfaction on turnover intention through burnout as a mediator. Work environment satisfaction, medical practicing environment satisfaction, and organizational management satisfaction proved to be negative predictors of turnover intention (p < 0.05), whereas reduced personal accomplishment was identified as a positive predictor (p < 0.05). Conclusions: Plagued by low job satisfaction and severe burnout, the PCPs in rural China may have high turnover intentions. Job satisfaction had not only negative direct effects on burnout and turnover intention, but also an indirect effect on turnover intention through burnout as a mediator. Targeted strategies should be taken to motivate and retain the PCPs. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
33. Enhanced Photocatalytic Nitrogen Fixation on MoO2/BiOCl Composite.
- Author
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Xiao, Cailin, Wang, Haipeng, Zhang, Ling, Sun, Songmei, and Wang, Wenzhong
- Subjects
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CHARGE carriers , *NITROGEN fixation , *INTERFACE structures , *ELECTRONIC structure , *WATER use , *CHEMISORPTION - Abstract
Converting N2 into NH3 under mild conditions is a great challenge because of the highly stable N≡N bond and the difficult chemisorption of N2 at the active site. Herein, we report that MoO2/BiOCl composites realized excellent photocatalytic nitrogen fixation efficiency when water was used proton source. The strong interaction between BiOCl nanoplates and MoO2 nanosheets regulated the electronic structure of the interface and provided active sites for the catalytic reaction. The Mo−O−Bi bonds formed at the interface of MoO2 and BiOCl worked as the bridge of electrons, facilitating the separation and migration of photo‐generated charge carriers. In addition, the interface of MoO2/BiOCl composite also promoted the adsorption and activation of N2, substantially enhanced N2 reduction. As a result, ammonia production rate of 35 μmol g−1 h−1 was achieved, which is 8‐fold higher than that of pristine BiOCl and 6‐fold higher than that of MoO2. This work presents a feasible route to design the nanocomposites with better performance for photocatalytic nitrogen fixation. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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- View/download PDF
34. Improved drug targeting to liver tumor by sorafenib-loaded folate-decorated bovine serum albumin nanoparticles.
- Author
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Wang, Haipeng, Sun, Shuilin, Zhang, Yu, Wang, Jiayi, Zhang, Shouhua, Yao, Xuebing, Chen, Ling, Gao, Zhen, and Xie, Baogang
- Subjects
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LIVER cancer , *SERUM albumin , *FOLIC acid , *DRUG target , *DRUG side effects , *TREATMENT effectiveness , *ZETA potential - Abstract
Background: To prepare sorafenib-loaded folate-decorated bovine serum nanoparticles (FA-SRF-BSANPs) and investigate their effect on the tumor targeting. Methods: The nanoparticles were characterized and evaluated by in vivo and in vitro experiments. Results: SRF-loaded BSA nanoparticles (SRF-BSANPs) was first prepared and modified with folic acid by chemical coupling to obtain FA-SRF-BSANPs. The average particle size, zeta potential, entrapment efficiency, and drug loading of the optimized FA-SRF-BSANPs were 158.00 nm, −16.27 mV, 77.25%, and 7.73%, respectively. The stability test showed that FA-SRF-BSANPs remained stable for more than 1 month at room temperature. The TEM analysis showed that the surface of FA-SRF-BSANPs was nearly spherical. XRD analysis showed that the drug existed in. the nanoparticles in an amorphous state. FA-SRF-BSANPs can promote the intracellular uptake of hepatoma cells (SMMC-7721) with the strongest inhibitory effect compared with SRF-BSANPs and sorafenib solution. Furthermore, the tumor targeting of FA-SRF-BSANPs (Ctumor/Cblood, 0.666 ± 0.053) was significantly higher than those of SRF-BSANPs (Ctumor/Cblood, 0.560 ± 0.083) and sorafenib-solution (Ctumor/Cblood, 0.410 ± 0.038) in nude mice with liver cancer. Conclusion: FA-modified albumin nanoparticles are good carriers for delivering SRF to the tumor tissue, which can improve the therapeutic effect and reduce the side effects of the drug. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
35. The association between self-efficacy and self-management behaviors among Chinese patients with type 2 diabetes.
- Author
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Yao, Jingjing, Wang, Haipeng, Yin, Xiao, Yin, Jia, Guo, Xiaolei, and Sun, Qiang
- Subjects
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TYPE 2 diabetes , *BLOOD sugar monitoring , *LOGISTIC regression analysis , *SELF-efficacy , *DIABETES , *CLUSTER sampling - Abstract
Background: Self-management is the cornerstone of diabetes care, however, despite the numerous recommendations available for self-management, type-2 diabetes mellitus (T2DM) patients' performance is suboptimal in China. This study aimed to explore the association between self-efficacy and self-management behaviors among Chinese T2DM patients, which might provide evidence to inform effective self-management interventions for these patients. Methods: A cross-sectional survey was conducted using a multi-stage stratified randomized sampling in Shandong Province, China. The Diabetes Empowerment Scale-Short Form (DES-SF) was used to measure patients' self-efficacy to manage diabetes. Latent class analysis (LCA) was used to explore the observed classes of self-management behaviors (dietary control, physical exercise, regular medication and self-monitoring of blood glucose). A two-class solution for self-management behaviors was tested to be the fittest based on LCA; we labelled active and inactive self-management groups. Univariate and multivariate logistic regression analysis were used to examine the associations between self-efficacy and self-management behaviors. Results: A total of 2166 T2DM patients were included in the analysis. The mean DES-SF score was 31.9 (standard deviation: 5.2). The estimated proportions of T2DM in the active and inactive groups were 54.8% and 45.2%, respectively. The multivariate logistic regression showed that higher DES-SF score was significantly associated with higher possibility of active self-management behaviors (odds ratio = 1.06; 95% confidence interval: 1.04–1.08). Conclusions: Self-efficacy in managing diabetes is associated with self-management behaviors among Chinese T2DM patients. To improve self-management behaviors, multiple strategies should be conducted to improve patients' self-efficacy. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
36. Effects of leading edge slat on flow separation and aerodynamic performance of wind turbine.
- Author
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Wang, Haipeng, Jiang, Xiao, Chao, Yun, Li, Qian, Li, Mingzhou, Zheng, Wenniu, and Chen, Tao
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FLOW separation , *WIND turbines , *WIND turbine blades , *AERODYNAMICS research , *EDGES (Geometry) - Abstract
The flow separation could affect the aerodynamic performance of the wind turbine blades and induce to occur the stall of the wind turbine blades at high angle of attack. The leading edge slat could effectively control and delay the flow separation. In this paper, the effects of the leading edge slat on the aerodynamic performance of the S809 airfoil and the Phase VI blade were investigated and the effects of the geometric parameters were considered. The aerodynamic performance of the S809 airfoil and the Phase VI blade was obtained using the RANS approach, and involved the standard transition model SST, k-omega turbulence model. It was shown that the leading edge slat had a great influence on the aerodynamic performance of the S809 airfoil and the Phase VI blade. For Case-1, when the angle of attack was 16.22°, the point of flow separation was shifted from x/c = 0.47 to 0.67, the lift coefficient increased by 52.99%. The torques of the total (included the wind turbine blade and leading edge slat) were increased except the torque of Blade-C1at 10 m/s. • The effects of the leading edge slat on the airfoil and blade were investigated. • The aerodynamic performance was obtained by the numerical simulation method. • The reasonable arrangement of the leading edge slat had a positive effect. • The leading edge slat can improve the aerodynamic performance of the blade. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
37. A novel carborane-containing ceramic precursor: Synthesis, characterization, and ceramic conversion mechanism.
- Author
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Tong, Dejin, Wang, Haipeng, Chen, Lei, Wang, Lei, and Li, Zhanxiong
- Subjects
- *
BENZENEDICARBONITRILE , *PROTON magnetic resonance , *LINEAR polymers , *NUCLEAR magnetic resonance , *MAGNETIC resonance , *CONVERSION disorder - Abstract
Linear carborane-carbosilane-phenylacetylene polymers have been synthesized as precursors for ceramic and characterized by Fourier transform infrared (FT-IR), proton nuclear magnetic resonance (1H-NMR), and carbon-nuclear magnetic resonance (13C-NMR). Novel linear polymers have the advantage of being extremely easy to process and convert into ceramics, since they are either viscous liquids or low melting solids at room temperature and are soluble in most organic solvents. Ceramic conversion reaction of the polymers was studied, and the conversion mechanism using thermogravimetric analyzer, FT-IR, and pyrolysis-gas chromatography-mass spectrometry was proposed. During the early heating period in the mechanism, the precursor polymer is cured and oligomer is formed. Then the degradation of oligomer takes place at higher temperatures with the weak bond cleaved and cross-linked simultaneously. Ceramic yield of the polymer after heating up to 1000°C in nitrogen (N2) was 77.6%. The derived ceramics exhibit excellent thermal and thermo-oxidative stability, whose 5% mass loss temperature was identified to be 650°C in N2 and 665°C in air, respectively. Boron appears to be the key element to achieve the outstanding thermo-oxidative stability. The relevant kinetic data were obtained by two kinds of model-free-kinetic algorithms, differential Friedman and integral Kissinger–Akahira–Sunose. These two methods were combined to give the energy profile, which has been identified to be a function of the transformation degree (α), since the energy demand at each degradation stage is different depending on α. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
38. Combined contralateral C7 to C7 and L5 to S1 cross nerve transfer for treating limb hemiplegia after stroke.
- Author
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Yang, Fangjing, Chen, Liwen, Wang, Haipeng, Zhang, Jionghao, Shen, Yundong, Qiu, Yanqun, Qu, Zhiwei, Li, Jie, and Xu, Wendong
- Subjects
- *
STROKE , *HEMIPLEGIA , *SPASTIC paralysis , *CEREBRAL hemorrhage , *NERVES - Abstract
Contralateral C7 to C7 cross nerve transfer has been proved to be safe and effective for patients with spastic arm paralysis due to stroke and traumatic brain injury. For the lower limb, contralateral L5 to S1 cross nerve transfer serves as a novel surgical approach. In many cases, patients with hemiplegia have both upper and lower limb dysfunction and hope to restore all limb functions within one operation. To cope with this demand, we performed combined contralateral C7 to C7 and L5 to S1 cross nerve transfer in two cases successfully. Two patients were enrolled in this study. The first patient is a 36-year-old woman who had spasticity and hemiplegia in both upper and lower limbs on the left side after a right cerebral hemorrhage 14 years prior. The second patient is a 64-year-old man who suffered from permanent muscle weakness in his right limbs, especially the leg, after a left cerebral hemorrhage 7 years prior. Both patients underwent the combined nerve transfer to improve upper and lower limb motor functions simultaneously. During the 10-month follow-up after surgery, the limb functions of both patients improved significantly. This study demonstrates the safety and benefits of combined contralateral C7 to C7 and L5 to S1 cross nerve transfer for hemiplegic patients after stroke. This novel combined surgical approach could provide an optimal choice for patients suffering from both upper and lower limb dysfunction, to reduce hospital stay while reducing financial burden. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
39. Direction of Arrival Estimation Method Based on Eigenvalues and Eigenvectors for Coherent Signals in Impulsive Noise.
- Author
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Cui, Junyan, Pan, Wei, and Wang, Haipeng
- Subjects
- *
DIRECTION of arrival estimation , *TOEPLITZ matrices , *EIGENVALUES , *MULTIPLE Signal Classification , *EIGENVECTORS , *COVARIANCE matrices - Abstract
In this paper, a Toeplitz construction method based on eigenvalues and eigenvectors is proposed to combine with traditional denoising algorithms, including fractional low-order moment (FLOM), phased fractional low-order moment (PFLOM), and correntropy-based correlation (CRCO) methods. It can improve the direction of arrival (DOA) estimation of signals in impulsive noise. Firstly, the algorithm performs eigenvalue decomposition on the received covariance matrix to obtain eigenvectors and eigenvalues, and then the Toeplitz matrix is created according to the eigenvectors corresponding to its eigenvalues. Secondly, the spatial averaging method is used to obtain an unbiased estimate of the Toeplitz matrix, which is then weighted and added based on the corresponding eigenvalues. Next, the noise subspace of the Toeplitz matrix is reconstructed to obtain the one that has less angle information. Finally, the DOA of the coherent signal is estimated using the Multiple Signal Classification (MUSIC) algorithm. The improved method based on the Toeplitz matrix can not only suppress the effect of impulsive noise but can also solve the problem of aperture loss due to its decoherence. A series of simulations have shown that they have better performances than other algorithms. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
40. Enzymatic degradation of fluorinated Poly(ε-caprolactone) (PCL) block copolymer films with improved hydrophobicity.
- Author
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Liu, Qun, Wang, Haipeng, Chen, Lei, Li, Wulong, Zong, Yakun, Sun, Yi, and Li, Zhanxiong
- Subjects
- *
FLUOROPOLYMERS , *BLOCK copolymers , *SCANNING electron microscopes , *DIFFERENTIAL scanning calorimetry , *MOLECULAR weights , *X-ray spectrometers - Abstract
Fluorinated Poly(ε-caprolactone) (PCL) block copolymers PCL-PTFOA(2 h), PCL-PTFOA(4 h), PCL-PTFOA(6 h), PCL-PTFOA(8 h) were prepared via esterification by using poly(1H,1H,2H,2H-perfluorooctylacrylate) (PTFOA) with different molecular weights as reactants. It was found that PCL-PTFOA(6 h) and PCL-PTFOA(8 h) possessed the similar molecular weight via GPC analysis. PCL and fluorinated PCL block copolymers films were prepared by solution casting method. The structure and properties of film surface of the fluorinated PCL block copolymers were analyzed by energy dispersive X-ray spectrometer (EDS), scanning electron microscope (SEM), Differential scanning calorimetry (DSC), water contact angles (WCAs) and the surface free energy. The results showed that the fluorinated PCL films possessed improved hydrophobicity because of the microphase separation between fluoropolymer chain and PCL chain. The enzymatic degradation of PCL, PCL-PTFOA(2 h), PCL-PTFOA(4 h) and PCL-PTFOA(6 h) films were performed at 37 °C in a phosphate buffer solution (PBS, 0.1 M, with a pH of 7.2–7.4) with lipase and analyzed by weight loss, SEM and EDS. It was found that the introduction of fluorine-containing segment reduced the rate of enzymatic degradation of the copolymer film in the early period, while increased the finally weight loss rate with a prolonged time. In addition, the enzymatic degradation rate of PCL-PTFOA(2 h) film and PCL-PTFOA(4 h) film was faster than that of PCL-PTFOA(6 h) film. • Fluorinated PCL block copolymers were synthesized and PCL-PTFOA films were prepared. • The hydrophobicity of the fluorinated PCL block copolymers was analyzed. • The degradation of fluorinated PCL block copolymers was investigated. • Introducing of fluorine-containing segments can reduce the enzymatic degradation rate of the PCL in the early period. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
41. Preparation of golf ball-shaped microspheres with fluorinated polycaprolactone via single-solvent electrospraying for superhydrophobic coatings.
- Author
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Li, Wulong, Wang, Haipeng, and Li, Zhanxiong
- Subjects
- *
POLYCAPROLACTONE , *FLUOROPOLYMERS , *MICROSPHERES , *COATED textiles , *SURFACE coatings , *MOLECULAR weights , *GOLF - Abstract
Graphical abstract Highlights • PCL- b -PTFOA copolymer was successfully synthesized via ATRP. • The golf ball-shaped microspheres were produced via one-step and single-solvent electrospraying technology. • A superhydrophobic fabric was produced via electrospraying with good washing and mechanical abrasion fastness. Abstract 1H,1H,2H,2H-Perfluorooctyl polyacrylate (PTFOA) with a controllable molecular weight was successfully synthesized via atom-transfer radical polymerization (ATRP) followed by condensation with polycaprolactone (PCL) to obtain a new fluorinated block copolymer. Then, the copolymer PCL- b -PTFOA was processed via single-solvent electrospraying in chloroform to fabricate hierarchically porous microspheres. The microsphere size could be controlled from 5.13 ± 0.51 μm to 8.61 ± 0.90 μm, and the pore size on the microsphere surface could be controlled from 282.5 ± 42.0 nm to 603.3 ± 99.6 nm. Solvent evaporation-induced phase separation and fluorinated segment migration are the major reasons for the formation of the golf ball-shaped microspheres. In this study, the influence of electro-spraying parameters on the size and morphology of the porous microspheres was systemically studied. The golf ball-shaped microspheres significantly improved the surface roughness and the CA of their coatings reached 167.3 ± 1.7°. Furthermore, a superhydrophobic fabric was produced by pretreating cotton fabric with adhesive followed by coating with PCL- b -PTFOA via electrospraying. The robust superhydrophobicity can be obtained by the stable binding of PCL- b -PTFOA microspheres onto the fibers, with the CA reaching 155.3 ± 1.1°. Electrospraying of the fluoropolymer microsphere coating was proven to be a very promising technique to produce superhydrophobic coatings on textiles through a simple procedure. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
42. Enhanced photocatalytic CO2 reduction to methane over WO3·0.33H2O via Mo doping.
- Author
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Wang, Haipeng, Zhang, Ling, Wang, Kefu, Sun, Xiang, and Wang, Wenzhong
- Subjects
- *
PHOTOCATALYSTS , *CARBON dioxide , *METHANE , *TUNGSTEN trioxide , *DOPING agents (Chemistry) , *CHEMICAL yield - Abstract
Graphical abstract Highlights • Homogeneous Mo doping in WO 3 ·0.33H 2 O leads to the increased yield and selectivity for CO 2 reduction to CH 4. • Mo doping in WO 3 ·0.33H 2 O facilitates CO 2 activation. • Tungsten bronze (H x WO 3 ·0.33H 2 O) formed under light irradiation, provides required electrons and protons for CO 2 reduction. • Enhanced water oxidation promotes protons supply for CH 4 generation. Abstract Photocatalytic CO 2 reduction is a promising strategy to address environmental and energy issues that are vexing the modern society. However, the efficiency of CO 2 photoreduction into fuels such as methane (CH 4) is substantially restricted by high CO 2 activation barrier and inefficient proton supply. Here, Mo-doped WO 3 ·0.33H 2 O nanorods have been synthesized and Mo doping in WO 3 ·0.33H 2 O dramatically increased the CH 4 production yield by 5.2 times from 1.02 to 5.3 μmol g cat −1 h−1 under water vapor without the assistant of any sacrificial agent or noble metal. The Mo doping proves capable of facilitating CO 2 activation by improving the ability to store and localize photogenerated electrons and boosting the transfer of photoexcited electrons to adsorbed CO 2. In addition, proton and electron insertion converts WO 3 ·0.33H 2 O into tungsten bronze (H x WO 3 ·0.33H 2 O) under light irradiation, guaranteeing required electrons and protons for CO 2 reduction. The enhanced water oxidation of Mo-doped WO 3 ·0.33H 2 O promotes proton supply and insertion process, improving the hydrogenation process of the carbon intermediate to generate CH 4. The combined action of the enhanced CO 2 activation and water oxidation with efficient proton and electron insertion improves the performance of CO 2 photoreduction to CH 4. This work might help to shed light on deeper insights into the design of CO 2 photoreduction catalysts. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
43. A Facile Strategy for Preparing PCL/PEG Block Copolymer Microspheres via Electrospraying as Coatings for Cotton Fabrics.
- Author
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Wang, Haipeng, Li, Wulong, and Li, Zhanxiong
- Subjects
- *
MICROSPHERES , *DRUG carriers , *POLYETHYLENE glycol , *SURFACE coatings , *COTTON textiles , *BLOCK copolymers , *POLYCAPROLACTONE - Abstract
Abstract: Polymeric microspheres can serve as microcarrier matrices and be used to prepare fabric coatings. After embedding spices or drugs in microspheres, and using them to coat fabrics, the coated fabrics can be applied to functional textiles. A facile one‐step, single‐solvent electrospray technology is utilized to produce polycaprolactone (PCL), PCL‐PEG400, and PCL‐PEG1000 microspheres with controlled sizes and tunable surface morphologies by adjusting parameters such as flow rate, voltage, and collection distance. Scanning electron microscopy coupled with an image analysis software (ImageJ) is employed to evaluate the size distribution and structures of the microspheres. Using PCL, PCL‐PEG400, and PCL‐PEG1000 as matrices, spherical particles with micro‐nanostructure surfaces are produced by adjusting the electrospraying parameters. According to observation and analysis results, PCL, PCL‐PEG400, and PCL‐PEG1000 form different microspheres with many porous pits, few pits, or nonporous wrinkles on a spherical surface, respectively. Increasing the flow rate or voltage produces larger or smaller microspheres, respectively. A slight increase in the average particle size is obtained by increasing the collection distance. Cotton fabrics pretreated with adhesive are directly coated by electrospraying to successfully enhance microsphere adhesion on fabric surfaces. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
44. Fabricating fragmented intramolecular D-A integrated carbon nitride photocatalyts with elevating activity: Performance and mechanism analysis.
- Author
-
Wang, Yanbo, Zhou, Tianyu, Wang, Haipeng, Wang, Liming, Qi, Ji, Cui, Keyu, Liu, Chunbo, and Hu, Bo
- Subjects
- *
HYDROGEN as fuel , *NITRIDES , *DOPING agents (Chemistry) , *PHOTOCATALYSTS , *HYDROGEN evolution reactions , *INTERSTITIAL hydrogen generation , *VISIBLE spectra , *PHOTODEGRADATION - Abstract
Carbon nitride (CN) possesses great potential in photocatalytic solar-energy conversion for environmental pollution removal and hydrogen energy generation. However, pristine CN suffers unsatisfactory photocatalytic activity owing to insufficient visible light response, low activity sites exposure, lazy exciton separation and ready carrier recombination. In this work, fragmented intramolecular D-A integrated CN (FBCN) was contracted via a facile m-aminophenylboronic acid doping followed two-step post-processing. The intramolecular D-A integrated structure can strengthen exciton separation and carrier migration driving forces, while the fragmented nanoflakes structure with rich in-plane edges can shorten the migration distance of charge-to-surface in-plane and vertical direction, as well as expose more marginal active sites. The hydrogen evolution rate of optimized 25-FBCN photocatalyst reaches 2545 μmol h−1 g−1, which is 5.2 times higher than that of pristine CN and 1.3 times over the 25-BCN. The 25-FBCN can degrade 87% sulfamethoxazole, and the kinetic rate constant is 3.9 times higher than that of CN. The radical capture and ESR tests reveal stronger radical signals in 25-FBCN degradation system than that of CN. The MS and online FTIR present photodegradation pathway and intermediate, and in-site record functional groups variation during degradation reaction. The SEM/TEM/AFM/XPS/EPR, N 2 adsorption-desorption and water contact analysis confirm the generation of smaller-sized nano fragments with rich in-plane edges. The UV–vis DRS/EIS/PCR/PL/TRPL and band structure verify that more effective charge dissociation/migration behavior of 25-FBCN than pure CN. Finally, DFT theoretical calculations and KPFM test further verify the generation of intramolecular D-A integrated structure and clarify the latent propel mechanism of performances. [Display omitted] • Fragmented intramolecular D-A integrated CN was constructed. • Specific surface area, light absorption, charge behaviors of 25-FBCN were enhanced. • 25-FBCN reveals propelled photocatalytic H 2 evolution and degradation activity. • MS, online FTIR, ESR and radicals capture clarified photodegradation mechanism. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
45. Planarizing Gysel power divider/combiner with ring coupler.
- Author
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Yi, Zixuan, Li, Chenchen, Wang, Haipeng, Yang, Xuexia, and Li, Meiling
- Subjects
- *
INSERTION loss (Telecommunication) , *PRINTED circuits , *POWER dividers - Abstract
This letter proposes a N‐way planar power divider/combiner using a combination of a Gysel power divider and a ring coupler. This innovative approach enables the realization of a fully planar multiway (>2) Gysel power divider. By replacing the common point of the conventional Gysel power divider with a ring coupler, the entire symmetrical divider can be implemented on a two‐layer printed circuit board. To validate the design concept, an eight‐way planar power divider is designed, fabricated, and tested. Experimental results obtained within the frequency range of 5.10–7.25 GHz (34.8% fractional bandwidth) demonstrate excellent performance. The insertion loss is below 1.24 dB, the input port return loss exceeds 12.65 dB, the output ports exhibit return loss greater than 14.83 dB, the isolation exceeds 22.41 dB, and the maximum measured phase imbalance is within ±2.7°. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
46. Photocatalytic conversion of CO2 to acetic acid by CuPt/WO3: Chloride enhanced C-C coupling mechanism.
- Author
-
Zeng, Di, Wang, Haipeng, Zhu, Xiaodi, Cao, Heng, Wang, Wenjing, Zhang, Yu, Wang, Juxue, Zhang, Ling, and Wang, Wenzhong
- Subjects
- *
COUPLING reactions (Chemistry) , *CARBON sequestration , *ACYL chlorides , *CARBON dioxide , *TUNGSTEN oxides , *ACETIC acid , *FISCHER-Tropsch process - Abstract
Photocatalytic converting CO 2 into value-added C 2+ fuels has attracted intense attention for CO 2 capture and utilization. Cu-based catalysts have shown the potential of photocatalytic CO 2 reduction for multi-carbon (C 2+) production. However, how the valance state and coordination environment affect the C-C coupling mechanism is unclear and requires further investigation. Herein, we investigate the influence of the coordination environments of hexagonal tungsten oxide (WO 3) photocatalyst loading with single-atom Cu and Pt. In this system, Cu(I) is stabilized by forming a coordinated complex, which increased the adsorption capacity of CO and extended the lifetime of CO* intermediate. Simultaneously, adjacent Pt sites provided protons for the hydrogenation of CO* intermediate. The results demonstrated that the coordination of chlorine ions with Cu/Pt was beneficial to the formation of C 2+ products. In this work, the Cu2Pt2/WO 3 exhibits a high photocatalytic CO 2 reduction activity with a yield of 19.41 μmol g−1 h−1 and a selectivity of 88.1%. [Display omitted] • Efficient CO 2 conversion into CH 3 COOH over Cu2Pt2/WO 3 photocatalyst. • The surface single-atom Cu and adjacent Pt sites accelerate the C-C coupling. • The coordination structure formed between Cl and Cu/Pt promotes CO 2 activation. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
47. Metagenomic reveals the methanogenesis metabolic mechanism of high-solids anaerobic digestion of human feces under gradient domestication.
- Author
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Wang, Haipeng, Sun, Hao, Ren, Hongyu, Cao, Guangli, Xie, Guojun, Xing, Defeng, Ren, Nanqi, and Liu, Bingfeng
- Subjects
- *
ANAEROBIC digestion , *ESCHERICHIA coli , *FECES , *METAGENOMICS , *FATTY acids , *RUMEN fermentation - Abstract
[Display omitted] • Gradient domestication could achieve high-solids anaerobic digestion of human feces. • Methane production rate was the highest when TS was increased to 11% • Granular sludge as inoculum can efficiently remove E. coli and Salmonella. • Key methanogenesis enzyme-encoding genes were increased abruptly at TS 12% and 13% • The main methanogenesis types were diverse at different TS loadings. High-solids anaerobic digestion (HSAD) of low C/N ratio waste was difficult to long-term running. In this study, human feces (HF) HSAD were operated in semicontinuous culture with HRT of 20 days for 190 days under mesophilic condition (38 ± 1 °C), granular sludge as inoculum was gradient domesticated by gradually increasing total solid (TS) (8 % to 17 %). The results showed that the highest tolerated concentration of TS achieved 16 % and biogas was stopped producing at TS 17 %. Maximum methane production rates of TS and volatile solid (VS) were obtained at TS 11 %, 287.08 mL/g TS and 67.67 mL/g vS respectively. AD system was inhibited when thresholds of total volatile fatty acids and total ammonia nitrogen were exceeded 2414.68 ± 207.62 mg/L and 4361.33 ± 143.86 mg/L, respectively. It was worth noted that granular sludge as an inoculum could efficiently remove pathogens (E. coli , 99.80 % at TS 11 % and Salmonella , 88.98 % at TS 12 %). High concentrations of HF (TS 13 % to 17 %) suppressed the growth of dominant methanogens (Methanothrix soehngenii , Methanothrix sp., and Methanothrix harundinacea.) and facilitated the rapid proliferation of acidogenic bacteria (Defluviitoga tunisiensis , Methanoculleus bourgensis , and Tepidanaerobacter acetatoxydans). The absolute abundance of key methanogenesis enzyme-encoding genes (mcr, frh, and fwd) were suddenly increased significantly at TS 12 % and 13 %. The main types of methanogenesis (acetoclastic at 11 % TS, hydrogenotrophic at 12 % TS and methylotrophic at 13 % TS) would change with the variation of different TS. The above studies provide guidance for HF HSAD domestication in practical AD applications. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
48. A review of recent advance of ship detection in single-channel SAR images.
- Author
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Zhang, Chunjie, Liu, Peng, Wang, Haipeng, and Jin, Yaqiu
- Subjects
- *
SYNTHETIC aperture radar , *MICROWAVE imaging , *SHIPS , *IMAGE sensors - Abstract
Synthetic aperture radar (SAR) is an active microwave imaging sensor for high-resolution observation, with the ability of working in all-weather and all-day. Recently, SAR images have been widely used in many fields. Among them, ship detection in single-channel SAR images is a significant part of civilian and military fields. This article first discusses the characteristic of SAR images and the detectability of ships, then summarizes the recent advance of traditional and deep learning-based methods used for ship detection in single-channel SAR images. In addition, the characteristics and existing problems of various methods are discussed and their future development trends are predicted. Aiming at the problems of the large amount of calculation, multi-scale and densely docked ship detection in single-channel SAR images, an improved deep learning-based detection algorithm is proposed, which has achieved excellent performance on the SAR ship detection dataset (SSDD). [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
49. Coating of poly(carborane-carbosilane-phenylacetylene) on carbon fibers with excellent oxidation protection.
- Author
-
Tong, Dejin, Wang, Haipeng, Wang, Lei, Chen, Lei, and Li, Zhanxiong
- Subjects
- *
CARBON fibers , *COPOLYMERS , *ETHYNYL benzene , *SURFACE coatings , *OXIDATION , *THERMOSETTING polymers , *PYROLYSIS - Abstract
Linear carborane-carbosilane-phenylacetylene co-polymer has been synthesized as precursor for thermosets and ceramics for the protection of carbon fibers from oxidation in an oxidizing environment. The novel linear co-polymers can be processed conveniently and converted into thermoset or ceramics since they are either liquids or low melting solids at room temperature and are soluble in most organic solvents. Treatment of carbon fibers with poly(carborane-carbosilane-phenylacetylene) by precursor infiltration and pyrolysis (PIP) process can provide a protective barrier at elevated temperatures. Tensile strength measurement revealed that the coated carbon fiber maintained 81.39% of its original strength. It was found that the novel co-polymer is highly efficient in protecting the carbon fibers from oxidation breakdown when used as a matrix material (ceramic). Boron and C C group appear to be the key to the unique oxidative stability of the composite compositions. The derived ceramic coatings on carbon fibers were characterized by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Anti-oxidation studies were performed by thermogravimetric analyses (TGA). The results showed that the oxidation resistance of carbon fibers has been promoted obviously by the ceramic coatings. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
50. A facile strategy for fabricating PCL/PEG block copolymer with excellent enzymatic degradation.
- Author
-
Wang, Haipeng, Tong, Dejin, Wang, Lei, Chen, Lei, Yu, Na, and Li, Zhanxiong
- Subjects
- *
BLOCK copolymers , *POLYETHYLENE glycol , *CHEMICAL decomposition , *POLYCAPROLACTONE , *HYDROXYL group , *ESTERIFICATION - Abstract
Poly(ω-caprolactone) (PCL) has been the focus in many research initiatives, especially regarding various ways though which to introduce reactive sites to the polyester chains. In this work, hydroxyl groups were covalently introduced into the chain of PCL by reacting ester groups with 6-amino-1-hexanol. Poly(ethylene glycol) (PEG) was crosslinked to the PCL chain through esterification, by using N,N’-carbonyldiimidazole (CDI) as catalyst. The prepared PCL-PEG copolymers were characterized by various analytical techniques such as Fourier transform infrared spectroscopy (FT-IR), 1 H NMR and X-ray photoelectron spectroscopy (XPS). Static water contact angles measurement indicated that hydrophilicity of the copolymer films modified by PEG has improved considerably. The copolymer films were prepared by casting the polymer solution onto a stainless plate. The degradation of the copolymer samples, in a phosphate buffer solution containing a type of Lipase (Aspergillus Oryzae), was observed at different time intervals. The results of weight loss ratio, during the degradation process, indicated that blocking PEG chains onto the PCL chains can effectively accelerate the process of enzymatic degradation of the resulting copolymer. The changes in molecular weight of the copolymer films were investigated by Gel Permeation Chromatography (GPC) and the copolymers were characterized by 1 H NMR during degradation. Surface morphology of PCL and PCL-PEG polymers, before and after degradation, was observed by Scanning electron microscopy (SEM), and emphasized that the enzymatic degradation of PCL-PEG copolymers occurred faster by comparison with PCL, starting from the surface layer of the films. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
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