27 results on '"Li, Zhiyi"'
Search Results
2. DGS-YOLOv8: A Method for Ginseng Appearance Quality Detection.
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Zhang, Lijuan, You, Haohai, Wei, Zhanchen, Li, Zhiyi, Jia, Haojie, Yu, Shengpeng, Zhao, Chunxi, Lv, Yan, and Li, Dongming
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IMAGE quality analysis ,CHINESE medicine ,COMPUTER vision ,DATA augmentation ,GINSENG - Abstract
In recent years, the research and application of ginseng, a famous and valuable medicinal herb, has received extensive attention at home and abroad. However, with the gradual increase in the demand for ginseng, discrepancies are inevitable when using the traditional manual method for grading the appearance and quality of ginseng. Addressing these challenges was the primary focus of this study. This study obtained a batch of ginseng samples and enhanced the dataset by data augmentation, based on which we refined the YOLOv8 network in three key dimensions: firstly, we used the C2f-DCNv2 module and the SimAM attention mechanism to augment the model's effectiveness in recognizing ginseng appearance features, followed by the use of the Slim-Neck combination (GSConv + VoVGSCSP) to lighten the model These improvements constitute our proposed DGS-YOLOv8 model, which achieved an impressive mAP50 of 95.3% for ginseng appearance quality detection. The improved model not only has a reduced number of parameters and smaller size but also improves 6.86%, 2.73%, and 3.82% in precision, mAP50, and mAP50-95 over the YOLOv8n model, which comprehensively outperforms the other related models. With its potential demonstrated in this experiment, this technology can be deployed in large-scale production lines to benefit the food and traditional Chinese medicine industries. In summary, the DGS-YOLOv8 model has the advantages of high detection accuracy, small model space occupation, easy deployment, and robustness. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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3. Generation of Pearl/Calcium Phosphate Composite Particles and Their Integration into Porous Chitosan Scaffolds for Bone Regeneration
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Li, Zhiyi, Rehman, Ihtesham U, Shepherd, Rebecca, Douglas, Timothy E. L., Li, Zhiyi, Rehman, Ihtesham U, Shepherd, Rebecca, and Douglas, Timothy E. L.
- Abstract
Bone tissue engineering using osteoconductive scaffolds holds promise for regeneration, with pearl powder gaining interest for its bioactive qualities. This study used freeze drying to create chitosan (CS) scaffolds with pearl/calcium phosphate (p/CaP) powders, mimicking bone tissue structurally and compositionally. Characterization included scanning electron microscopy (SEM) and mechanical testing. X-ray diffraction (XRD) Fourier-transform infrared–photoacoustic photo-acoustic sampling (FTIR−PAS), and FTIR- attenuated total reflectance (FTIR-ATR) were used to characterize p/CaP. In vitro tests covered degradation, cell activity, and SEM analysis. The scaffolds showed notable compressive strength and modulus enhancements with increasing p/CaP content. Porosity, ranging from 60% to 90%, decreased significantly at higher pearl/CaP ratios. Optimal cell proliferation and differentiation were observed with scaffolds containing up to 30 wt.% p/CaP, with 30 wt.% pearl powder and 30 wt.% p/CaP yielding the best results. In conclusion, pearl/calcium phosphate chitosan (p/CaP_CS) composite scaffolds emerged as promising biomaterials for bone tissue engineering, combining structural mimicry and favourable biological responses.
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- 2024
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4. Urbanization Effect on Changes in Extreme Climate Events in Urumqi, China, from 1976 to 2018.
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Abulimiti, Aerzuna, Liu, Yongqiang, Yang, Lianmei, Abulikemu, Abuduwaili, Mamitimin, Yusuyunjiang, Yuan, Shuai, Enwer, Reifat, Li, Zhiyi, Abuduaini, Abidan, and Kadier, Zulipina
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CLIMATE extremes ,ARID regions climate ,CLIMATE change ,URBAN heat islands ,URBANIZATION ,CLIMATE change denial - Abstract
This study investigates, for the first time, the urbanization effect (UE) on local extreme climate events in Urumqi, China, based on 22 indices of climate extremes, which are calculated with daily observation data from 1976 to 2018. These analyses reveal a pronounced nocturnal urban heat island (UHI) effect and a daytime urban cold island (UCI) effect. Due to Urumqi's arid climate background, the UCI effect is considered a unique feature of the UE, which significantly differs from those in eastern and northern China. The UE on the TR20 index (number of days with minimum daily temperature exceeding 20 °C) reached 5.22 d/10a, indicating that urbanization has led to a fast increase in the number of hot nights in Urumqi. The absolute averaged UE on the indices measuring the frequency of warm events is about twice as large as that on the indices measuring the frequency of cold events, while that on the indices measuring the intensity of warm events is about one third of that on the indices measuring the intensity of cold events. The highest averaged urbanization contributions (UCs) to the extreme warm and cold events are represented by the frequency indices and the intensity indices, respectively, while those contributing to the extreme precipitation events are represented by the duration indices. Moreover, urbanization probably exacerbates the degree of wetting in the overall "warming and wetting" climate trend of the region. These findings can be seen as new evidence to provide scientific basis for further investigation of the UE on climate changes in arid regions. [ABSTRACT FROM AUTHOR]
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- 2024
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5. Multi-Plant Disease Identification Based on Lightweight ResNet18 Model.
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Ma, Li, Hu, Yuanhui, Meng, Yao, Li, Zhiyi, and Chen, Guifen
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PLANT diseases ,CONVOLUTIONAL neural networks - Abstract
Deep-learning-based methods for plant disease recognition pose challenges due to their high number of network parameters, extensive computational requirements, and overall complexity. To address this issue, we propose an improved residual-network-based multi-plant disease recognition method that combines the characteristics of plant diseases. Our approach introduces a lightweight technique called maximum grouping convolution to the ResNet18 model. We made three enhancements to adapt this method to the characteristics of plant diseases and ultimately reduced the convolution kernel requirements, resulting in the final model, Model_Lite. The experimental dataset comprises 20 types of plant diseases, including 13 selected from the publicly available Plant Village dataset and seven self-constructed images of apple leaves with complex backgrounds containing disease symptoms. The experimental results demonstrated that our improved network model, Model_Lite, contains only about 1/344th of the parameters and requires 1/35th of the computational effort compared to the original ResNet18 model, with a marginal decrease in the average accuracy of only 0.34%. Comparing Model_Lite with MobileNet, ShuffleNet, SqueezeNet, and GhostNet, our proposed Model_Lite model achieved a superior average recognition accuracy while maintaining a much smaller number of parameters and computational requirements than the above models. Thus, the Model_Lite model holds significant potential for widespread application in plant disease recognition and can serve as a valuable reference for future research on lightweight network model design. [ABSTRACT FROM AUTHOR]
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- 2023
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6. Diurnal Variation Characteristics of Summer Precipitation over the Northern Slope of the Tianshan Mountains, Xinjiang, Northwest China: Basic Features and Responses to the Inhomogeneous Underlying Surface.
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Kadier, Zulipina, Li, Zhiyi, Abulikemu, Abuduwaili, Zhu, Kefeng, Abulimiti, Aerzuna, An, Dawei, and Abuduaini, Abidan
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AUTOMATIC meteorological stations , *INFLUENCE of altitude , *ORTHOGONAL functions , *BODIES of water , *SUMMER - Abstract
The diurnal variation characteristics of precipitation in summer (June–August) during the period of 2015–2019 over the Northern Slope of the Tianshan Mountains (NSTM) was analyzed using hourly simulated data from Nanjing University's real-time forecasting system (WRF_NJU) with 4 km resolution, Automatic Weather Station (AWS) data, and the ERA5-Land data through using methods such as the Rotated Empirical Orthogonal Function (REOF) and Coefficient of Variation (CV). The results show that the diurnal variation pattern of the precipitation over the NSTM simulated by WRF_NJU aligns closely with that of the observational AWS data, and it captured spatial distribution, peak values, and the times of precipitation reasonably well. The hourly precipitation amount (PA), precipitation frequency (PF), and precipitation intensity (PI) all show characteristics of being greater in the afternoon to nighttime than from early morning to noon, and the diurnal variations of precipitation in this region are significantly influenced by altitude. The PA, PF, and PI peak over the southern edge of the Junggar Basin (JB) below 1000 m occurred at around 2200 Local Solar Time (LST). In contrast, peak PA over the mountainous regions above 3000 m occurred at around 1500 LST. Further analysis with REOF and CV indicated that the difference in diurnal variations of precipitation between the mountainous regions and the JB is most pronounced likely due to the topographical influences. The peak PA over the mountainous regions mainly occurred at around 1500 LST, while that of the JB occurred at around 0100 LST. High CV regions for PI are predominantly found over the area near the central JB and the middle Tianshan mountains, whereas high CV regions for the PF are located in the central and northern parts of Urumqi and Changji. In addition, different land surface categories exhibit distinct patterns of diurnal precipitation variation, i.e., the forests, grasslands, and water bodies exhibit their peak PA in the period from early morning to noon, while the impervious surfaces, croplands, and barren lands exhibit their peak PA in the period from afternoon to nighttime. [ABSTRACT FROM AUTHOR]
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- 2023
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7. A Case Study on the Convection Initiation Mechanisms of an Extreme Rainstorm over the Northern Slope of Kunlun Mountains, Xinjiang, Northwest China.
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Sun, Qi, Abulikemu, Abuduwaili, Yao, Junqiang, Mamtimin, Ali, Yang, Lianmei, Zeng, Yong, Li, Ruqi, An, Dawei, and Li, Zhiyi
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RAINSTORMS ,HEAT convection ,TEMPERATURE lapse rate ,VERTICAL wind shear ,THERMAL instability ,BOUNDARY layer (Aerodynamics) ,WIND speed - Abstract
Extreme precipitation events have been occurring frequently worldwide, and their causative factors and convection initiation (CI) mechanisms have been attracting more and more attention in recent years. As a comprehensive study on the CI mechanisms of extreme rainstorms over the northern slope of the Kunlun Mountains (KLM), Xinjiang, based on both observational and high tempo-spatial numerical simulation, the major findings of this work are as follows: A cold pool (CP) was formed in the northwestern Tarim Basin under the influence of early precipitation evaporation, and it moved towards the northern slope of the KLM several hours before the CI. With the movement of the CP, a significant vertical temperature gradient was formed close to the leading edge of the CP, thereby enhancing local convective instability (up to ~10 PVU). In addition, the vertical shear of the horizontal winds at the leading edge of the CP led to a notable increase in the baroclinic component of moist potential vorticity, thus reinforcing the local conditional symmetric instability (up to ~8 PVU), providing another important unstable energy for the CI. In addition, the combined effect of the convergent lifting of a boundary layer jet (BLJ, the maximum wind speed below 1 km exceeding 10 m s
−1 ) and the significant frontogenetical forcing (up to ~100 × 10−8 K m−1 s−1 ) at the leading edge of the CP were the causes of the release of the unstable energies. Further analysis of the frontogenetical forcing associated with the CP indicates that the convergence (up to ~2 × 10−3 s−1 ), diabatic heating and slantwise terms (indicates the baroclinicity and inhomogeneity of the vertical momentum in horizontal direction) were the major contributors, whereas the deformation term at the leading edge of the CP provided a relatively weaker contribution. [ABSTRACT FROM AUTHOR]- Published
- 2023
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8. Diurnal Variation Characteristics of Summer Precipitation and Related Statistical Analysis in the Ili Region, Xinjiang, Northwest China.
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Li, Zhiyi, Abulikemu, Abuduwaili, Zhu, Kefeng, Mamtimin, Ali, Zeng, Yong, Li, Jiangang, Abulimiti, Aerzuna, Kadier, Zulipina, Abuduaini, Abidan, Li, Chunyang, and Sun, Qi
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METEOROLOGICAL research , *WEATHER forecasting , *ORTHOGONAL functions , *STATISTICS , *WATER vapor - Abstract
The diurnal variation characteristics and basic statistical features of summer precipitation (from June to August) in the Ili region from 2015 to 2019 were investigated based on 4 km resolution Weather Research and Forecasting model simulation data from Nanjing University (WRF_NJU). The results show that the overall diurnal variation characteristics of precipitation (DVCP) reflected by the WRF_NJU data were consistent with respect to the observations and reanalysis data. The total precipitation pattern exhibited high (low) values on the east (west), with higher (lower) values over the mountainous (valley) area. Hourly precipitation amount (PA), precipitation frequency (PF), and precipitation intensity (PI) show similar diurnal variation characteristics, with peaks occurring at around 1700 LST in the mountainous area and around 2000 LST in valleys. Furthermore, moderate to intense precipitation contributes up to 87.88% of the total precipitation. The peaks in the mountainous area occur earlier than the valleys, while the peaks in western part of the valleys occur earlier than the eastern part. The PA peaks over the valleys and slopes occurred from the evening to early morning and from the afternoon to evening, respectively. In addition, the rotated empirical orthogonal function (REOF) analysis implied that the DVCP exhibits distinct differences between mountainous and valleys, and peak precipitation occurs during the evening in basin– and wedge–shaped areas, while the mountain peaks and foothill regions exhibit semi–diurnal variation characteristics. Among several basic meteorological factors, the vertical velocity (VV) and water vapor mixing ratio (WVMR) provided major contributions to the DVCP in both areas with high and low coefficients of variation, and the WVMR (VV) probably played a more significant role in mountainous (valleys) areas. [ABSTRACT FROM AUTHOR]
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- 2023
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9. CLT-YOLOX: Improved YOLOX Based on Cross-Layer Transformer for Object Detection Method Regarding Insect Pest.
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Zhang, Lijuan, Cui, Haibin, Sun, Jiadong, Li, Zhiyi, Wang, Hao, and Li, Dongming
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INSECT pests ,PESTS - Abstract
This paper presents an enhanced YOLOX-based algorithm for pest detection, adopting a nature-inspired approach for refining its methodology. To tackle the limited availability of image data pertaining to pests and diseases, the paper incorporates Mosaic and Mixup technologies for effective image preprocessing. Furthermore, a novel training strategy is proposed to enhance the overall quality of the results. The existing architecture is enriched by integrating shallow information, while the CLT module is devised to facilitate cross-layer fusion and extract essential feature information. This advancement enables improved object detection across various scales. Additionally, the paper optimizes the original PFPN structure by eliminating the convolutional layer preceding upsampling, enhancing the C3 module, and integrating the convolutional attention model (CBAM) to identify salient regions within complex scenes. The performance of the proposed CLT-YOLOX model is extensively evaluated using the IP102 dataset, demonstrating its effectiveness. Notably, the model exhibits significant improvements compared to the original AP evaluation index, with an increase of 2.2% in average precision (mAP) and 1.8% in AP
75 . Furthermore, favorable results are achieved in the COCOmAP index, particularly in the APsmall category where there is a 2.2% improvement in performance. [ABSTRACT FROM AUTHOR]- Published
- 2023
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10. Effects of Dietary Supplementation with Mulberry Leaf Powder on the Growth Performance, Lipid Metabolism Parameters, Immunity Indicators, and Gut Microbiota of Dogs.
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Yu, Aiying, Tang, Cuiming, Wang, Sutian, Wang, Yuan, Chen, Lian, Li, Zhiyi, Luo, Guoqing, Zhong, Jianwu, Fang, Zhengfeng, Wang, Zhenjiang, and Lin, Sen
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LIPID metabolism ,DIETARY supplements ,IMMUNOGLOBULINS ,LEAF growth ,LDL cholesterol ,GUT microbiome ,DOG walking ,FRUCTOOLIGOSACCHARIDES ,LIPIDS - Abstract
Overfeeding and a lack of exercise are increasingly causing obesity in dogs, which has become a big problem threatening the health of dogs. Therefore, it is necessary to investigate how dietary regulations can help to improve dogs' body conditions and minimize obesity. This study was carried out to investigate the effects of dietary mulberry leaf powder (MLP) supplementation on the growth performance, lipid metabolism parameters, and gut microbiota of Chinese indigenous dogs. Fifteen Chinese indigenous dogs (6.34 ± 0.56 kg) were randomly assigned to three treatment groups and received either the control diet (CON), high-fat diet (HF), or high-fat diet containing 6% Mulberry leaf powder (MLP) for four weeks. The CON group received a basal diet, the HF group received a basal diet supplemented with 10% lard, and the MLP group received a basal diet supplemented with 10% lard and 6% MLP. The trial lasted for four weeks. The growth performance, lipid metabolism parameters, immune globulins, cytokines, and fecal microbiota were measured. Results showed that there was no significant difference in growth performance. The MLP group appeared to have decreased (p < 0.05) the serum level of low-density lipoprotein cholesterol (LDL-C) and apoliprotein-A1(APO-A1) in serum. The MLP group appeared to have higher (p < 0.05) serum immune globulin A (IgA) levels. UPGMA results showed that the MLP group was closer to the CON group than to the HF group. LEfSe analysis showed that dietary supplementation with MLP contributed to an alteration in the genus Alloprevotella, Sarcina, and species belonging to the Bacteroides and Lactobacillus genus. Overall, the dietary supplementation of 6% MLP can improve lipid metabolism conditions and immunity in high-fat-diet-fed dogs, and can alter the gut microbial composition of dogs. [ABSTRACT FROM AUTHOR]
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- 2023
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11. Hardware Design and Implementation of a Lightweight Saber Algorithm Based on DRC Method.
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Zheng, Weifang, Zhang, Huihong, Zhang, Yuejun, Wen, Yongzhong, Lv, Jie, Ni, Lei, and Li, Zhiyi
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STATIC random access memory ,QUANTUM computers ,ALGORITHMS ,CLOCKS & watches ,HARDWARE ,CRYPTOSYSTEMS - Abstract
With the development of quantum computers, the security of classical cryptosystems is seriously threatened, and the Saber algorithm has become one of the potential candidates for post-quantum cryptosystems (PQCs). To address the problems of long delay and the high power consumption of Saber algorithm hardware implementation, a lightweight Saber algorithm hardware design scheme based on the joint optimization of data readout and clock (DRC) was proposed. Firstly, an analysis was carried out on the hardware architecture, timing overhead and power consumption distribution of the Saber algorithm, and the key circuits that limit the performance of the algorithm were identified; secondly, a dual-port SRAM parallel reading method was adopted to improve the data reading efficiency and reduce the timing overhead of double data reading in the multiplier module. Then, a clock gating technology was used to reduce the dynamic flipping probability of internal registers and reduce the hardware power consumption of the Saber algorithm; finally, data reading and clock gating were jointly optimized to design a high-speed and low-power Saber algorithm hardware IP core. Lightweight IP cores were integrated into RISC-V SoC systems via APB bus in a TSMC 65 nm process to complete the digital back-end design. The experimental results show an IP core area of 0.99 mm
2 and power consumption of 8.49 mW, which is 33% lower than that reported in the related literature. Under 72 MHz & 1 V operating conditions, the number of clock cycles for the Saber algorithm's key generation, encryption and decryption are 3315, 9204 and 1420, respectively. [ABSTRACT FROM AUTHOR]- Published
- 2023
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12. Study on Cl − Erosion of Concrete under the Combined Effect of Fatigue Load and Wet–Dry Cycles: A Review.
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Zhang, Maohua, Li, Zhiyi, Cui, Jiyin, and Xu, Ronghua
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FATIGUE (Physiology) ,CONCRETE durability ,SOIL erosion ,REINFORCED concrete ,CONCRETE ,CORROSION fatigue - Abstract
The service environment of concrete in the marine environment is harsh, and demands regarding the durability of marine concrete have increased. Marine concrete in harbor and wharf areas suffers from the combined effect of fatigue load, dry–wet cycles, and Cl
− erosion, which can result in spalling of the concrete surface, corrosion of the internal reinforcement, and even concrete damage. This paper reviews recent research results on the durability of concrete and reinforced concrete (RC) under the combined effect of fatigue load, dry–wet cycles, and Cl− erosion. We further assess the variation in Cl− transport properties with fatigue load, the causes behind the reduction in the carrying capacity of RC products under fatigue load, the methods of Cl− erosion on concrete under the pressures imposed by dry–wet cycles, and the damage of the protective layer of concrete due to accelerated Cl− erosion caused by the action of dry–wet cycles. Further studies are needed on the durability of concrete under the action of fatigue load, wet and dry cycles, and Cl− erosion, in addition to the testing of the durability of concrete under the combined effects of the afore-mentioned various factors. [ABSTRACT FROM AUTHOR]- Published
- 2023
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13. On the Mechanisms of a Snowstorm Associated with a Low-Level Cold Front and Low-Level Jet in the Western Mountainous Region of the Junggar Basin, Xinjiang, Northwest China.
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He, Xiaoning, Abulikemu, Abuduwaili, Mamtimin, Ali, Li, Ruqi, Abulimiti, Aerzuna, An, Dawei, Aireti, Mangsuer, Zhou, Yaman, Sun, Qi, Li, Zhiyi, Yuan, Lin, and Xi, Tao
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VERTICAL wind shear ,SNOWSTORMS ,TROPICAL cyclones ,BAROCLINICITY - Abstract
Snowstorms frequently hit large parts of the Northern Hemisphere, and their causative factors have been drawing increasing attention in recent years. As the first in-depth study on the mechanisms of a snowstorm associated with a low-level cold front (LLCF) and low-level westerly jet (LLWJ) in the western mountainous region of the Junggar Basin, Xinjiang, based on both observations and numerical simulation, the major findings of this work are as follows: At the early stage, instabilities were mainly dominated by inertial instability (II) occurring near the core region of the LLWJ, while the lower level was mainly controlled by the baroclinic component of moist potential vorticity (MPV2), which was mainly contributed by the vertical shear of the horizontal wind, which is also located near the LLWJ. At the later stage, II was released significantly, whereas the MPV2 still supported snowfall clouds. Further analysis based on the decomposition of the frontogenetical forcing required for the release of the instabilities indicated that the slantwise term was the major contributor, whereas convergence and deformation also played significant roles at low levels above the windward slope. The slantwise term resulted from the combined effects of baroclinicity due to the LLCF and the inhomogeneity of the momentum due to the LLWJ. [ABSTRACT FROM AUTHOR]
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- 2023
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14. The Effects of Dietary Inclusion of Mulberry Leaf Powder on Growth Performance, Carcass Traits and Meat Quality of Tibetan Pigs.
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Wang, Sutian, Tang, Cuiming, Li, Jianhao, Wang, Zhenjiang, Meng, Fanming, Luo, Guoqing, Xin, Haiyun, Zhong, Jianwu, Wang, Yuan, Li, Baohong, Li, Zhiyi, Chen, Lian, Hu, Bin, and Lin, Sen
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MEAT quality ,LEAF growth ,SWINE ,MULBERRY ,SHEARING force ,DIETARY supplements - Abstract
Simple Summary: In recent years, consumers have been paying more and more attention to the flavor and texture of pork, and, therefore, the Chinese indigenous pig breeds, like Tibetan pigs, are valued for good meat quality. Herein, we investigated whether dietary mulberry leaf powder could further improve the meat quality of Tibetan pigs. Our results indicated improved meat quality in Tibetan pigs who consumed mulberry leaf powder, which might be the consequence of enhanced antioxidant activity and altered muscle fiber type and morphology. This research was conducted to study the effects of dietary inclusion of mulberry leaf powder (MLP) on growth performance, meat quality, antioxidant activity, and carcass traits of Tibetan pigs. Eighteen Tibetan pigs (33.8 ± 1.1 kg) were assigned to two treatment groups randomly and received either the control diet (CON) or a basal diet containing 8% MLP (MLP) for two months. After the two-month feeding trial, the MLP group showed lower backfat thickness while a higher lean percentage. Compared with CON pigs, MLP pigs had higher serum CAT activity. In addition, dietary MLP supplementation significantly decreased the muscle shear force. Muscle fiber morphology analysis showed that MLP pigs had larger muscle fiber density while smaller muscle fiber cross-sectional area. Up-regulated gene expression of myosin heavy chain (MyHC)IIa was also observed in MLP pigs. These results indicate that the enhanced antioxidant activity and altered muscle fiber type and morphology appeared to contribute to the improvement of meat quality in Tibetan pigs fed diets containing MLP. [ABSTRACT FROM AUTHOR]
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- 2022
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15. Restoration of Mitochondrial Function Is Essential in the Endothelium-Dependent Vasodilation Induced by Acacetin in Hypertensive Rats.
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Li, Yuan, Dang, Qingya, Li, Zhiyi, Han, Chuting, Yang, Yan, Li, Miaoling, and Li, Pengyun
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VASODILATION ,ENDOTHELIUM ,MITOCHONDRIA ,TRANSMISSION electron microscopes ,ENDOTHELIUM diseases ,HYPERTENSION - Abstract
Mitochondrial dysfunction in the endothelium contributes to the progression of hypertension and plays an obligatory role in modulating vascular tone. Acacetin is a natural flavonoid compound that has been shown to possess multiple beneficial effects, including vasodilatation. However, whether acacetin could improve endothelial function in hypertension by protecting against mitochondria-dependent apoptosis remains to be determined. The mean arterial pressure (MAP) in Wistar Kyoto (WKY) rats, spontaneously hypertensive rats (SHR) administered with acacetin intraperitoneally for 2 h or intragastrically for six weeks were examined. The endothelial injury was evaluated by immunofluorescent staining and a transmission electron microscope (TEM). Vascular tension measurement was performed to assess the protective effect of acacetin on mesenteric arteries. Endothelial injury in the pathogenesis of SHR was modeled in HUVECs treated with Angiotensin II (Ang II). Mitochondria-dependent apoptosis, the opening of Mitochondrial Permeability Transition Pore (mPTP) and mitochondrial dynamics proteins were determined by fluorescence activated cell sorting (FACS), immunofluorescence staining and western blot. Acacetin administered intraperitoneally greatly reduced MAP in SHR by mediating a more pronounced endothelium-dependent dilatation in mesenteric arteries, and the vascular dilatation was reduced remarkably by NG-nitro-L-arginine methyl ester (L-NAME), an inhibitor of NO synthesis. While acacetin administered intragastrically for six weeks had no apparent effect on MAP, it improved the endothelium-dependent dilatation in SHR by activating the AKT/eNOS pathway and protecting against the abnormalities of endothelium and mitochondria. Furthermore, acacetin remarkably inhibited Ang II induced apoptosis by inhibiting the increased expression of Cyclophilin D (CypD), promoted the opening of mPTP, ROS generation, ATP loss and disturbance of dynamin-related protein 1 (DRP1)/optic atrophy1 (OPA1) dynamics in HUVECs. This study suggests that acacetin protected against endothelial dysfunction in hypertension by activating the AKT/eNOS pathway and modulating mitochondrial function by targeting mPTP and DRP1/OPA1-dependent dynamics. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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16. Fast Filling of Microvia by Pre-Settling Particles and Following Cu Electroplating.
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Li, Ganglong, Li, Zhiyi, Li, Junjie, and Wu, Houya
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PACKAGING , *METALS - Abstract
Microvia interconnectors are a critical element of 3D packaging technology, as they provide the shortest interconnection path between stacked chips. However, low efficiency of microvia filling is a long-standing problem. This study proposed a two-step method to enhance the electroplating filling efficiency by pre-setting metal particles in microvias and later electroplating the Cu to fill the gaps among the pre-settled particles. Since these particles occupy a certain volume in the microvia, less electroplating Cu is needed for microvia filling, leading to a shorter electroplating period. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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17. Design of a Low-Profile Wideband Magnetoelectric Dipole Antenna with Reduced Gain Drop.
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Li, Zhiyi, Chen, Xing, Tang, Yuzhu, Liao, Liangbing, Deng, Linwan, and Zhao, Zhifan
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DIPOLE antennas ,ANTENNAS (Electronics) ,BANDWIDTHS - Abstract
In this paper, a novel low-profile magnetoelectric (ME) dipole antenna with wideband is presented. The conventional vertical fixing structure is bended four times from the center to the sides. The Γ-shaped feeding structure is bended two times to lower the height of the antenna step by step. The effect of three kinds of vertical wall is discussed to show their influence on boresight gain. Through comparison, only one vertical wall is erected on the left side of the ground to decrease the boresight gain drop at 2.2 GHz. Both simulation and analysis are made to sufficiently explain the working principle. At last, the proposed ME dipole antenna has only 0.095λ
0 (λ0 is the center operating wavelength in free space) in height, and the wideband property is still maintained. By simulation, the relative bandwidth for VSWR < 2.0 is 47.9% (from 1.35 to 2.2 GHz). The boresight gain ranges from 8.1 to 9.6 dBi in the operating band. The measured relative bandwidth for VSWR < 2.0 is 50.3% (from 1.34 to 2.24 GHz), and the boresight gain ranges from 7.38 to 8.73 dBi. The gain drop on boresight is less than 1.4 dBi. Radiation patterns show a unidirectional characteristic in the whole operating band. Additionally, the cross-polarization level is less than −25 dB on boresight. The simulating and measuring results agree well with each other. Therefore, the proposed antenna is suitable for applications of limited height and wideband. [ABSTRACT FROM AUTHOR]- Published
- 2022
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18. Short Text Aspect-Based Sentiment Analysis Based on CNN + BiGRU.
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Gao, Ziwen, Li, Zhiyi, Luo, Jiaying, and Li, Xiaolin
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SENTIMENT analysis ,CONVOLUTIONAL neural networks ,ARTIFICIAL neural networks ,USER-generated content - Abstract
This paper describes the construction a short-text aspect-based sentiment analysis method based on Convolutional Neural Network (CNN) and Bidirectional Gating Recurrent Unit (BiGRU). The hybrid model can fully extract text features, solve the problem of long-distance dependence on the sequence, and improve the reliability of training. This article reports empirical research conducted on the basis of literature research. The first step was to obtain the dataset and perform preprocessing, after which scikit-learn was used to perform TF-IDF calculations to obtain the feature word vector weight, obtain the aspect-level feature ontology words of the evaluated text, and manually mark the ontology of the reviewed text and the corresponding sentiment analysis polarity. In the sentiment analysis section, a hybrid model based on CNN and BiGRU (CNN + BiGRU) was constructed, which uses corpus sentences and feature words as the vector input and predicts the emotional polarity. The experimental results prove that the classification accuracy of the improved CNN + BiGRU model was improved by 12.12%, 8.37%, and 4.46% compared with the Convolutional Neural Network model (CNN), Long-Short Term Memory model (LSTM), and Convolutional Neural Network (C-LSTM) model. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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19. Semi-Supervised Training of Transformer and Causal Dilated Convolution Network with Applications to Speech Topic Classification.
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Zeng, Jinxiang, Zhang, Du, Li, Zhiyi, and Li, Xiaolin
- Subjects
AUTOMATIC speech recognition ,SPEECH perception ,CLASSIFICATION - Abstract
Aiming at the audio event recognition problem of speech recognition, a decision fusion method based on the Transformer and Causal Dilated Convolutional Network (TCDCN) framework is proposed. This method can adjust the model sound events for a long time and capture the time correlation, and can effectively deal with the sparsity of audio data. At the same time, our dataset comes from audio clips cropped by YouTube. In order to reliably and stably identify audio topics, we extract different features and different loss function calculation methods to find the best model solution. The experimental results from different test models show that the TCDCN model proposed in this paper achieves better recognition results than the classification using neural networks and other fusion methods. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
20. Deep Reinforcement Learning-Based Multi-Hop State-Aware Routing Strategy for Wireless Sensor Networks.
- Author
-
Zhang, Aiqi, Sun, Meiyi, Wang, Jiaqi, Li, Zhiyi, Cheng, Yanbo, Wang, Cheng, and Mukhopadhyay, Subhas
- Subjects
WIRELESS sensor networks ,DEEP learning ,RECURRENT neural networks ,WIRELESS mesh networks ,TRAFFIC estimation ,REINFORCEMENT learning ,TRAFFIC flow - Abstract
With the development of wireless sensor network technology, the routing strategy has important significance in the Internet of Things. An efficient routing strategy is one of the fundamental technologies to ensure the correct and fast transmission of wireless sensor networks. In this paper, we study how to combine deep learning technology with routing technology to propose an efficient routing strategy to cope with network topology changes. First, we use the recurrent neural network combined with the deep deterministic policy gradient method to predict the network traffic distribution. Second, the multi-hop node state is considered as the input of a double deep Q network. Therefore, the nodes can make routing decisions according to the current state of the network. Multi-hop state-aware routing strategy based on traffic flow forecasting (MHSA-TFF) is proposed. Simulation results show that the MHSA-TFF can improve transmission delay, average routing length, and energy efficiency. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
21. Dual-Polarized Dipole Antenna for Wireless Data and Microwave Power Transfer.
- Author
-
Liao, Liangbing, Li, Zhiyi, Tang, Yuzhu, and Chen, Xing
- Subjects
WIRELESS power transmission ,DIPOLE antennas ,MICROWAVES - Abstract
This manuscript presents a broadband high-efficiency dual-polarized dipole antenna for wireless power and data transfer. The proposed antenna mainly consists of cross-dipole patches, matching baluns, and a ground plane. The dual-polarized radiation mode was achieved by using two linear-polarization matching baluns to feed the cross-dipole patches orthogonally. The proposed dual-polarized dipole antenna realizes a bandwidth with S
11 less than −10 dB (4.28 GHz–5.92 GHz) and a high radiation efficiency of about 95%. An independent rectifying circuit was designed, and a microwave energy transmission experiment was carried out. The final measured conversion efficiency for the two polarized ports at 5.8 GHz was about 77.6% and 76.4%, respectively. Simulation and measurement results showed that the proposed antenna is suitable for both wireless power and wireless data transfer applications. [ABSTRACT FROM AUTHOR]- Published
- 2022
- Full Text
- View/download PDF
22. Dual-Polarized Stacked Patch Antenna for Wireless Communication Application and Microwave Power Transfer.
- Author
-
Liao, Liangbing, Li, Zhiyi, Tang, Yuzhu, and Chen, Xing
- Subjects
MICROWAVE communication systems ,ANTENNAS (Electronics) ,WIRELESS communications ,ANTENNA design ,WIRELESS power transmission - Abstract
In this paper, a dual-polarized stacked patch antenna for wireless communication and microwave power transfer is proposed. The stacked antenna consists of four rectangular apertures that are etched on the ground plane and four identical cross-placed coupling strips that are set on the upper layer of the ground plane, which are used to excite the top-layer patches. The presented stacked patch antenna was designed as a completely symmetric structure except for the feeding network, resulting in a simple structure and the same radiation patterns for the two polarized ports. The proposed antenna operates at around 5.8 GHz, and the simulation and measured results show that it has a gain of 8.5 dBi and an isolation of 25 dB. The measured antenna efficiency of the two polarized ports at 5.85 GHz was 89.2% and 88.6%, respectively. Finally, a rectifying circuit was designed, and the maximum measured conversion efficiency of the two polarized rectenna was 63.5% and 62.7%, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
23. Sentimental Knowledge Graph Analysis of the COVID-19 Pandemic Based on the Official Account of Chinese Universities.
- Author
-
Li, Xiaolin, Li, Zhiyi, and Tian, Yahe
- Subjects
COVID-19 pandemic ,KNOWLEDGE graphs ,NETWORK governance ,PUBLIC universities & colleges ,STATE universities & colleges ,SOCIAL networks - Abstract
With the advent of the new media mobile Internet era, the network public opinion in colleges and universities, as an extension of social network public opinion, is also facing a crisis in the prevention, control, and governance system. In this paper, the Fiddler was used to collect the comments and other relevant data of the COVID-19 topic articles on the WeChat Official Accounts of China's top ten universities in 2020. The BILSTM_LSTM sentiment analysis model was used to analyze the sentiment tendency of the comments, and the LDA topic model was used to mine the topics of the comments with different emotional attributes at different stages of COVID-19. Based on sentiment analysis and text mining, entities and relationships in the theme graph of public opinion events in colleges and universities were identified, and the Neo4j graph database was established to construct the sentimental knowledge graph of the pandemic theme of university public accounts. People's attitudes in university public opinion are easily influenced by a variety of factors, and the degree of emotional disposition changes over time, with the stage the pandemic is in, and with different commentators; official account opinion topics change with the development of the time stage of the pandemic, and students' positive and negative comment topics show a diverse trend. By incorporating topic mining into the sentimental knowledge graph, the graph can realize functions such as the emotion retrieval of comments on university public numbers, a source search of security threats in university social networks, and monitoring of comments on public opinion under the theme of the pandemic, which provides new ideas for further exploring the research and governance system of university network public opinion and is conducive to preventing and resolving campus public opinion crises. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
24. The Research on the Construction and the Photocatalytic Performance of BiOI/NH 2 -MIL-125(Ti) Composite.
- Author
-
Du, Juan, Zhang, Jiaxin, Yang, Tingyu, Liu, Renming, Li, Zhiyi, Wang, Dandan, Zhou, Tong, Liu, Yucun, Liu, Chunbo, and Che, Guangbo
- Subjects
PHOTOCATALYSTS ,RHODAMINE B ,VISIBLE spectra ,SPECTRUM analysis ,SURFACE area ,CONSTRUCTION - Abstract
The BiOI/NH
2 -MIL-125(Ti) composite photocatalyst with excellent photocatalytic performance was prepared by the solvothermal method. For the BiOI/NH2 -MIL-125(Ti) (BNMT) system, the contents of NH2 -MIL-125(Ti) in BNMT-4, BNMT-5, BNMT-7, BNMT-9, and BNMT-10 were 4 wt %, 5 wt %, 7 wt %, 9 wt %, and 10 wt %, respectively. XRD, XPS, SEM, and TEM characterizations indicated that BiOI/NH2 -MIL-125(Ti) was successfully prepared. Brunauer, Emmett, and Teller (BET) and UV–vis diffuse reflectance spectra photoelectrochemical analysis indicated that BNMT-9 can make the specific surface area and photo absorption region larger than BiOI. In addition, the separation efficiency of photogenerated carriers was improved, and the recombination efficiency was reduced. The degradation percentages of Rhodamine B (RhB) and p-chlorophenol (P-CP) reached 99% and 90% over BNMT-9 under visible light irradiation. Additionally, the catalysts had high stability. The results of the active spices trapping experiments test indicated that h+ was the main active species. The possible degradation mechanism was proposed. [ABSTRACT FROM AUTHOR]- Published
- 2021
- Full Text
- View/download PDF
25. Multi-period Market Operation of Transmission-Distribution Systems Based on Heterogeneous Decomposition and Coordination.
- Author
-
Liu, Cong, Zhou, Jingyang, Pan, Yi, Li, Zhiyi, Wang, Yifei, Xu, Dan, Ding, Qiang, Luo, Zhiqiang, and Shahidehpour, Mohammad
- Subjects
BANK reserves ,MARKETING ,MARKET equilibrium ,MIXED integer linear programming ,DECOMPOSITION method ,MARKET prices ,STOCHASTIC programming - Abstract
The integration of shiftable/curtailment distribution generators (DGs) along with quick-response storage has not only increased the transaction's flexibility but also puzzled the bidding willingness of transmission-connected market players (TMPs). In this paper, the method of heterogeneous decomposition and coordination (HGDC) is applied to decompose the integrated transmission-distribution market framework into a bi-level problem with a transmission wholesale market master problem and several distribution retail market subproblems in a decentralized organization structure. The price-based bidding willingness of demand-side resources' (DSRs') aggregator is simulated considering the relation between distribution system operator's (DSO's) operation modes and its equivalent market transactive price. Besides the traditional mixed-integer linear programming (MILP) model, the active reconfiguration model of DSOs based on mixed-integer second-order conic programming (MI-SOCP) is proposed to rearrange its operation switch status and elaborate its operation cost according to the market transaction. Multi-period optimal operation modes could be obtained through an HGDC-based iteration process by coordinating the transmission system operator (TSO) with DSOs and considering the market energy equilibrium and reserve requirements for security considerations. Karush-Kuhn-Tucker (KKT) conditions are used to testify the optimality and convergence of the bi-level model in theory. The T5-3D33 case is employed to illustrate the efficiency of the proposed model and method. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
26. Hybrid AC/DC Microgrid Planning with Optimal Placement of DC Feeders.
- Author
-
Wu, Xiong, Wang, Zhao, Ding, Tao, and Li, Zhiyi
- Subjects
ELECTRIC potential ,POWER resources ,RENEWABLE energy sources ,DIRECT currents ,ENERGY storage - Abstract
With the significant increase in DC loads (such as data and telecommunication centers) at the power distribution level, an additional set of power electronic converters are required to connect these DC loads to the AC-dominant power network. Notably, hybrid AC/DC microgrids (MGs) serve as promising solutions to satisfying both the AC and DC loads with a reduced number of installed converters. Since DC loads may be randomly distributed in the MG, how to place DC feeders to simultaneously fulfill the economic and security requirements of MG operations remains a challenging problem. To address this issue, this paper proposes a hybrid AC/DC MG planning model to determine the optimal placement of DC feeders with the objective of minimizing the total cost of the investment of distributed energy resources (DERs), converters, and AC/DC distribution lines, as well as the operation of DERs. In particular, the power flow of the hybrid AC/DC MG is derived in a unified manner and then incorporated in the planning model. Eventually, the proposed model suffices to find the optimal number and siting for both DERs and DC feeders while ensuring the continuality of the DC feeders. The proposed model is tested in two MG-based distribution systems, and its effectiveness is validated by the results of numerical experiments. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
27. Temporal Variation and Reduction Strategy of Nutrient Loads from an Urban River Catchment into a Eutrophic Lake, China.
- Author
-
Qin, Chengxin, Li, Zhiyi, Xie, Pengcheng, Hao, Qianting, Tang, Xuejun, Wu, Yihui, and Du, Pengfei
- Subjects
WATERSHEDS ,EUTROPHICATION ,RUNOFF ,WATER quality ,SEWAGE - Abstract
Excessive nutrient input from urban areas increases the occurrence of eutrophication. Control of nutrient loads is perceived as the primary restoration method. Quantifying temporal variation of nutrient loads is essential to understand the dynamic relationships of nutrient source-impacts in the urban water system and investigate the operational efficiency of treatment facilities for eutrophication control. Here, a holistic approach was developed to estimate nutrient loads from different sources and evaluate nutrient impacts on the urban water environment. An integrated catchment model of nutrient loads was built and applied to calculate river nutrient loads from untreated rainfall runoff, untreated sewage, and treated recharge into the eutrophic Dianchi Lake from an urban river catchment with limited infrastructure. Nutrient impacts on the lake were evaluated and a load reduction strategy was given a hint to reduce nutrient impacts of urban rivers. During the study period 2014–2016, nutrient loads from the urban river generally decreased except during heavy winter rainfall events and high-intensity pollution events associated with rainfall runoff. The average contribution of annual nutrient loads to the lake capacity indicated the underestimation of nutrient impacts of urban rivers. This approach provides new insights into urban water management and underscores the importance of sewage infrastructure. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
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