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In this study, CuS nanoparticles with optical absorption covering both near-infrared I (NIR-I) and NIR-II biological windows were prepared and served as the contrast agents for multispectral photoacoustic imaging. The physiological parameters including concentrations of deoxyhemoglobin and oxyhemoglobin as well as the water content in the tumor location were quantified based on the multispectral photoacoustic reconstruction method. More importantly, the concentration of CuS nanoparticles/drugs accumulated in the tumor was also recovered after intravenously injection, which are essential for image-guided cancer theranostics. In addition, phantom and in vivo experimental tests were performed to inspect and compare the imaging depth and signal-to-noise ratio (SNR) between the two NIR biological windows. Interestingly, we discovered that a higher SNR was obtained in the NIR-II window than that in the NIR-I window. Meanwhile, the multispectral imaging results also demonstrated that the imaging contrast and penetration depth in the NIR-II window were also significantly improved as compared to those from the NIR-I window.

International audience; Photoacoustics is a hybrid modality used to image biological tissues. As optical absorption of tissues depends on the wavelength of the transmitted light, multispectral photoacoustic datasets can be obtained by changing this wavelength. This study presents a regularization method to segment multispectral photoacoustic images based on both the spatial and spectral features of the dataset pixels. The proposed processing is adapted from the spatiotemporal mean-shift approach and cluster patterns with similar spectral profiles, i.e., the variation of the received amplitude among the wavelengths, independent of their initial position. The segmentation performance of this method has been experimentally tested on multispectral photoacoustic tomographic data. We initially used a phantom that contained fresh and stale liver samples, and then a second phantom that contained two blood dilutions or a colored absorber. Experimentally, a clustering performance greater than 98% is achieved. This method makes it possible to discriminate between different media, between the same medium as fresh or stale, and between the same medium with different dilutions.

In order to improve the accuracy and precision of online learning-based collision detection methods, an online active ensemble learning for robot collision detection (OAELRCD) is proposed in this paper. The OAELRCD consists of two key components: (1) an ensemble learning method to combine several base classifiers in order to improve the accuracy and precision of collision detection, (2) an active learning algorithm to reduce the number of training samples in order to realize online training and learning when the environment changes. We evaluate the proposed OAELRCD on one robot arm in dynamic environments with moving workspace obstacles, showing that the proposed OAELRCD outperforms state-of-the-art online learning-based method and geometric collision checkers. Compared to the state-of-the-art online learning-based method for robot collision detection in dynamic environments, the proposed OAELRCD provides noticeable improvements in TPR, AUC, Accuracy and TNR. Compared to state-of-the-art geometric collision checkers, with the proposed OAELRCD, collision checks are faster.

Ammonia volatilization is an important way to lose nitrogen fertilizer in Agricultural Ecosystems, and the main source of ammonia volatilization in the world comes from ammonia volatilization in agriculture. Ammonia volatilization not only reduces the utilization rate of nitrogen fertilizer in farmland, leading to the waste of resources, but also leads to environmental problems such as air quality decline, soil acidification and water eutrophication. The paper reviews the characteristics of furrow irrigation, drip irrigation and sprinkler irrigation and the research results of soil ammonia volatilization under several irrigation methods. It provides a theoretical basis for selecting suitable irrigation management measures to reduce the emission of ammonia volatilization in farmland system.

The technology of the electric vehicle battery overheating and its thermal runaway prevention is becoming research hotspots. This paper proposes an active control method of refrigerant spray to inhibit heat and combustion in thermal accidents. The rapid cooling, suppression of oxygen and flame of the battery module are achieved through the collaborative active control of the spray nozzle and the venting port. The research is carried out with the intermittent spray mode of the refrigerant under the conditions of overall overheating and local overheating. The cooling characteristics and combustion blocking ability of the battery in three typical active control modes of the venting port are compared and analyzed. Studies indicate that the active control of the venting port can effectively prevent the dissipation of the cold energy of the gasified refrigerant in both the case of overall overheating and local overheating, which significantly enhances the cooling capacity, uniformity of temperature change and oxygen suppression effect of the emergency spray cooling compared with that without the active control. In all, the proposed method can further improve the safety of electric vehicles, and win more time for passengers to escape in thermal accidents.

MoSi 2 based materials have the potential for use in high temperature structural parts. In this work, WSi 2 reinforced MoSi 2 composites were successfully prepared by mechanical activation followed by in situ reactive spark plasma sintering of Mo, Si, and W elemental powders. Benefiting from the high energy raw materials prepared through ball milling, these mechanically activated reactants started to transform into MoSi 2 at 1000 °C. Full density composites were obtained at a low sintering temperature (1200 °C) within 5 min. The addition of W to the reactants led to a finer microstructure than that obtained using pure MoSi 2 , resulting in a significant improvement of mechanical properties. The Vicker's hardness of 20 vol% WSi 2 /MoSi 2 was as high as 16.47 GPa.

Small molecules participate extensively in various life processes. However, specific and sensitive detection of small molecules in a living system is highly challenging. Here, we describe in vivo real-time dynamic monitoring of small molecules by a luminescent polymer-dot oxygen transducer. The optical transducer combined with an oxygen-consuming enzyme can sensitively detect small-molecule substrates as the enzyme-catalyzed reaction depletes its internal oxygen reservoir in the presence of small molecules. We exemplify this detection strategy by using glucose-oxidase-functionalized polymer dots, yielding high selectivity, large dynamic range, and reversible glucose detection in cell and tissue environments. The transducer-enzyme assembly after subcutaneous implantation provides a strong luminescence signal that is transdermally detectable and continuously responsive to blood glucose fluctuations for up to 30 days. In view of a large library of oxygen-consuming enzymes, this strategy is promising for in vivo detection and quantitative determination of a variety of small molecules.

Purpose: The aim of this study was to develop novel methods for photoacoustically determining the optical absorption coefficient of biological tissues using Monte Carlo (MC) simulation. Methods: In this study, the authors propose two quantitative photoacoustic tomography (PAT) methods for mapping the optical absorption coefficient. The reconstruction methods combine conventional PAT with MC simulation in a novel way to determine the optical absorption coefficient of biological tissues or organs. Specifically, the authors’ two schemes were theoretically and experimentally examined using simulations, tissue-mimicking phantoms, ex vivo, and in vivo tests. In particular, the authors explored these methods using several objects with different absorption contrasts embedded in turbid media and by using high-absorption media when the diffusion approximation was not effective at describing the photon transport. Results: The simulations and experimental tests showed that the reconstructions were quantitatively accurate in terms of the locations, sizes, and optical properties of the targets. The positions of the recovered targets were accessed by the property profiles, where the authors discovered that the off center error was less than 0.1 mm for the circular target. Meanwhile, the sizes and quantitative optical properties of the targets were quantified by estimating the full width half maximum of the optical absorption property. Interestingly, for the reconstructed sizes, the authors discovered that the errors ranged from 0 for relatively small-size targets to 26% for relatively large-size targets whereas for the recovered optical properties, the errors ranged from 0% to 12.5% for different cases. Conclusions: The authors found that their methods can quantitatively reconstruct absorbing objects of different sizes and optical contrasts even when the diffusion approximation is unable to accurately describe the photon propagation in biological tissues. In particular, their methods are able to resolve the intrinsic difficulties that occur when quantitative PAT is conducted by combining conventional PAT with the diffusion approximation or with radiation transport modeling.

A gravity balance mechanism for spatial robotic manipulator is proposed. In this design, a parallelogram linkage mechanism, pulleys and springs are utilized to accomplish the balance. As a passive structure, it needs no motors or actuators, and safety is another great highlight of the mechanism. The balance mechanism can solve the balance problem of both planar 2-link mechanism and spatial 2-link mechanism (a roll-pitch-yaw-roll 2-link mechanism) by adding a rotational degree of freedom. This is a more simple and effective method to solve the balance problem of spatial linkage system, especially the linkage system of multi-degree of freedom joint. And the mechanism can be extended to solve a multilink balance problem.

Mobile robots working in special environment have to adapt for unknown and complex environment characteristics, so high mobility, functional versatility and robustness of mobile robots are required. Different from specialized robot designed for single function in single environment, single unit of modular reconfigurable robots has simple mechanical structure, flexible movement and maneuverability; meanwhile, the combination of multiple units has flexible and versatile configuration, combined with distributed control and swarm intelligence algorithm to gain environmental adaptability and functional versatility of the entire reconfigurable robot system. Single unit of modular mobile reconfigurable robots could complete lightweight tasks such as transporting medicines, distributing and accompanying nurses. Meanwhile, the combination of multiple units could complete heavyweight tasks such as transporting patients and large medical equipment. Modular mobile reconfigurable robot system has broad application prospects in the field of medical auxiliary robots.

As there come to be more applications of intelligent robots, their task object is becoming more varied. However, it is still a challenge for a robot to handle unfamiliar objects. We review the recent work on the feature sensing and robotic grasping of objects with uncertain information. In particular, we focus on how the robot perceives the features of an object, so as to reduce the uncertainty of objects, and how the robot completes object grasping through the learning-based approach when the traditional approach fails. The uncertain information is classified into geometric information and physical information. Based on the type of uncertain information, the object is further classified into three categories, which are geometric-uncertain objects, physical-uncertain objects, and unknown objects. Furthermore, the approaches to the feature sensing and robotic grasping of these objects are presented based on the varied characteristics of each type of object. Finally, we summarize the reviewed approaches for uncertain objects and provide some interesting issues to be more investigated in the future. It is found that the object’s features, such as material and compactness, are difficult to be sensed, and the object grasping approach based on learning networks plays a more important role when the unknown degree of the task object increases.

Copper nanowire (CuNW) is one of the most promising candidates for next-generation transparent conductive film (TCF). However, practical applications of CuNW are still limited by several drawbacks, including loose wire to wire junctions, poor resistance against oxidation, chemical and thermal damage. To concurrently address these urgent issues, highly conductive and stable TCF is prepared based on Cu@Ni core-shell NW networks by electrodeposition. The coated Ni shell can weld stacked NWs tightly, which decreases the sheet resistance from 513 to 15.8 Ohm/sq (at a transmittance of 88%), as well as improves the mechanical stability (1.03-fold resistance increase after 2000 cyclic bending). The Cu@Ni NW TCF exhibits excellent antioxidation performance after storing in atmospheric environment for 168 h. The passivation Ni shell also improvs the chemical and thermal stability. The Cu@Ni NW network keeps intact after 450 s H2O2 corrosion and heating at 400 °C for 30 min. Moreover, a flexible transparent heater was fabricated based on these TCFs, which shows excellent uniform heating performance and high response speed.

Land use/cover change (LUCC) in the Bohai Rim coastal zone has accelerated as a result of rampant economic development, which has directly caused many negative effects on ecosystem functions and services. Based on multi-temporal land use data (2000, 2005, 2010 and 2015), the benefit transfer method was used to assess the ecosystem service value (ESV) of the Bohai Rim coastal zone, and the impact of LUCC on ecosystem services was studied. Multi-scenario simulations for 2025 were conducted using the future land use simulation model. The result of the analysis showed that during the period from 2000 to 2015, the total ESV lost was 22.09 billion yuan, representing a decrease of 3.80%. The spatial distribution of the ESV showed a certain regularity, with obvious characteristics of a land-sea gradient change. As the distance from the coastline increased, the ESV per unit area gradually declined. Compared with those in 2015, the total ESVs of the socio-economic development scenario and the business-as-usual scenario in 2025 showed a declining trend, while they increased under the ecological protection priority scenario. Under the ecological protection priority scenario, regulating services and support services increased significantly, but those declined dramatically under the socio-economic development scenario. The patterns of LUCC are the main reasons for the decrease in ESV. This research provides a theoretical basis and support for the development and utilization of coastal space and the improvement of “ecological-economic-social” benefits; additionally, the results provide support for scientific decision-making services for the sustainable use of resources in the coastal zone and for the sustainable management of ecosystems.

Aiming at non-linear problems existing in the principle of variable stiffness of robot joints, a class crank-slider and planetary gear mechanism are presented. The spring is pre-compressed by using the inter-agency geometric relations of fulcrum movement. The approximate linear variation of stiffness about fulcrum offset is realized. The problems of mechanism clearance, operational stability, and compact space are solved. The joint stiffness calculation method is derived, and the relationship between key parameters and stiffness outputs is analyzed. The stiffness control strategy is researched on, and a trajectory generator is designed based on Taylor series expansion. Static stiffness identification and dynamic stiffness following experiment are designed to test joint stiffness and position characteristics. The feasibility of joint is verified to achieve stiffness and position continuous adjustment within a certain range. This type of joint can be used in the field of medical treatment and rehabilitation to solve the problems of safety and environmental adaptability in the application process.

The thermal problems in the underhood are serious in the integrated thermal management of electric vehicles. The interaction of the heat dissipation components in the underhood affects the heat exchange and working performance, which affects its driving range and safety. This paper takes the interactive thermal influence into consideration between the battery, motor and air conditioning system, builds an underhood thermal management system framework of electric vehicles, and establishes a 1D/3D coupling model for the integrated systems. Only the components in the underhood are studied in 3D. The impact of load change of the air conditioning system and power system on heat transfer performance of another system is studied under different heat exchanger layouts. The results show that the cooling effect of the power system decreases with the load of the air conditioning system increasing when the condenser is placed in front of the radiators. When the condenser is behind the radiators, the air conditioning system load change has no significant effect on the heat dissipation effect of the power system. For both arrangements, the load change of the power system has an evident influence on the refrigeration process of the air conditioning system. The dissipated heat of the condenser decreases as the power system load increases, and the COP increases gradually. At the same time, the cooling performance number is introduced to evaluate the heat dissipation capacity of the power system and the air conditioning system. The smaller the cooling performance number, the stronger the heat dissipation capability of the system, and vice versa, the worse the heat dissipation capability. So it can further optimize the cooling characteristics and safety of the entire electric vehicle by comprehensively considering the arrangement or the targeted optimization of the heat exchangers to improve the integrated thermal management system of EVs.

Engineering conjugated polymer nanoparticles (CPNs) with an easily-modified surface is essential to construct multifunctional nanoprobes as contrast agents for dual-modal photoacoustic (PA) and fluorescence imaging, which can take advantages of the complementary information from a single modality. In this study, an abundant protein with plenty of functional groups was introduced for the first time to produce easily-modified CPNs, leading to a robust nanoplatform to engineer PA-based multifunctional nanoprobes due to their strong optical absorption in the near-infrared region. Meanwhile, the bovine serum albumin (BSA)-modified CPNs were further engineered by introducing gold clusters in situ, which can serve as fluorescent nanoprobes for dual-modal molecular imaging. In particular, the developed nanoplatform exhibited superior stability and excellent biocompatibility, making it an ideal candidate for various cancer-theranostics applications. More importantly, our imaging results demonstrated that the BSA-modified CPNs were excellent candidates to design PA-based contrast agents for multimodal imaging using the function of the protein. In addition, other functional blocks can also be added to the nanoplatform based on its easily-modified surface, making it a general method for the construction of multifunctional nanoprobes for disease theranostics.

Human walking is quite an efficient and smooth movement involving multiple successive phases. But for biped robots, most current dynamic walking models are simplified to some extent, with some phases neglected. This paper addresses the development of a complete multi-phase dynamics model for a biped robot. To achieve this, both the single support phase and double support phase are divided into two sub-phases by taking into consideration the rotation of stance foot around its toe and the rotation of swing foot around its heel. Therefore, a more human-like robotic gait is achieved, with transitions occurring at toe-off, heel-off, heel-strike, and toe-strike. Comparing the numbers of degrees of freedom with independent actuators of the biped robot, the whole gait cycle can also be represented by fully-actuated phase, under-actuated phase, and over-actuated phase. On this basis, the detailed dynamics model of each phase is derived using Euler-Lagrange method. And the validity of the dynamics model is demonstrated by simulation.

The metatarsophalangeal (MTP) joints play critical roles in the push-off phase of human locomotion, but are usually absent in biped robots. Our previous research found that when the unilateral MTP joints were restricted, non-disabled subjects exerted a compensatory mechanism, that is, the intact limb was relied more than the restricted limb. This paper aims to study the effects of unilateral restrictions of the MTP joints on biped robot walking. Gait performance of a biped robot model was analyzed under two conditions, i.e., walking normally, and walking with the MTP joints of the right foot restricted. The results show that unilateral restrictions of the MTP joints lead to larger demands for driving torque and power on partial joints, more total energy consumption, and lower energy efficiency. These results can help understand the functions of the MTP joints in more depth, and offer some inspirations to the researches of biped robots.

Two new species of Marphysa Quatrefages, 1865 (Polychaeta: Eunicida: Eunicidae), M. bulla n. sp. and M. maxidenticulata n. sp., are described from the northern coast of China with comments on the usefulness of pectinate chaetae to separate species. A redescription of Marphysa orientalis Treadwell, 1936 originally described from China is given. The genus Marphysa is widely collected for bait for recreational fishermen and anglers in China and is also exported to Australia and Japan, yet the number of species involved or their native distribution are currently unknown. It is critical that aquaculture programs know which species they are attempting to breed and their native distributional ranges. A key to all described species of Marphysa from China, including two new species described in this paper is given.

Three new species of Marphysa Quatrefages, 1865 (Polychaeta: Eunicida: Eunicidae) are described from the south coast of China, M. tripectinata n. sp., M. multipectinata n. sp. and M. tribranchiata n. sp. with comments on the usefulness of pectinate chaetae to separate species. Marphysa sinensis Monro, 1934 is redescribed with a lectotype designated. The genus Marphysa is widely collected for bait and export for recreational fishermen and anglers in China and yet the number of species involved and their native distribution is currently unknown. Such information is critical for aquaculture programs which are rearing these species.

The miR-490-3p was transfected into HepG2 cells to explore the correlation between miR-490-3p and hepatocellular carcinoma cell proliferation, apoptosis, and autophagy and its downstream target gene ATG7. Then we could possibly provide a mechanism for the treatment of hepatocellular carcinoma. MiR-490-3p was screened out by fold change 4 and P 0.01 using gene microarray data. The expression level of miR-490-3p was tested by qRT-PCR and the prognosis analysis was achieved by using TCGA data. The cell proliferation was tested via colony formation assay and CCK-8 after the miR-490-3p mimics were transfected into HepG2 cells; the variations of cell cycle and apoptosis was examined by flow cytometry assay; the number of autophagosome was observed by electron microscopy and the changes of autophagy-relative protein LC-II and LC-I as well as their ratio was tested by western blot. MiR-490-3p is low expressed in hepatocellular carcinoma cell lines and tissues. The results of TCGA showed that miR-490-3p high expression indicated better prognosis. After HepG2 cells were transfected with miR-490-3p mimics, cell viability was increased, cell proliferation was enhanced, cell cycle was blocked in G0/G1 phase, cell apoptosis rate was increased, the number of autophagosomes was reduced, autophagy-associated protein LC-II was decreased, and LC-I was increased and their ratio was decreased. After 3-MA was added, cell proliferation was declined, cell apoptosis rate was increased. Besides, the autophagy was inhibited by knocking down the ATG7, which promoted the cell apoptosis. MiR-490-3p could suppress cell proliferation, retard cell cycle and upgrade cell apoptosis by inhibiting autophagy in HCC cells via targeting ATG7. © 2018 IUBMB Life, 70(6):468-478, 2018.

Gradient projection is the common inverse-solution method for kinematically redundant manipulators during realtime tracking the planned path in obstacles environment. However, the end-effector of kinematically redundant manipulators usually cannot achieve an ideal tracking of the planned path due to the calculation errors. This paper presents an improved real-time scheme based on the gradient projection for redundant manipulators to realize the accurate kinematically tracking in multi-obstacles environment. The real-time path is planned according to the shortest path principle. Gradient projection method is used to calculate the inverse kinematics on the basis of the planned path in real time. The strategy of fixing joint angles is proposed to restrict several joint motion by considering the priorities of the distance between manipulator and obstacles, and the singular position. The unrestricted joint angles are compensated by secondary calculation method to reduce the errors caused by gradient projection method. Then, the accurate tracking can be achieved and the object is thus grasped in multi-obstacles environment. The simulation results based on an 8-DOF planar manipulator show that the proposed algorithm is feasible and owns accurate tracking ability.

In the present article, the asymptotic speed of spread and traveling wavefronts of a partial neutral functional differential equation (PNFDE) are investigated. A variable transform yields to a partial retarded functional differential equation (PRFDE) with infinite number of constant delays. The relation between the above PNFDE and PRFDE is studied and an equivalence in a certain meaning of these two equations is verified. Using this equivalence, we in fact obtain the existence and uniqueness of solution for the initial value problem of the PNFDE. We then consider the truncated system of the above PRFDE, which is a partial retarded functional differential equation with finite number of constant delays. We establish the existence of the traveling wave solution and the spreading speed for this truncated system. A limit argument and the method of finite delay approximation are used to obtain the existence of the traveling wave solutions and the spreading speed for the PRFDE with infinite number of constant delays. This leads to the existence of the traveling wave solution and the spreading speed for the considered PNFDE by the above equivalence. At last, we confirm that the spreading speed is coincidental with the minimal wave speed for all equations. An example is given to illustrate the application of our results.

In the present work, Nb doped brookite TiO2 nanosheets were successfully synthesized via a one-step hydrothermal route. The synthesized samples were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning and transmission electron microscopy (SEM/TEM) and X-ray photoelectron spectroscopy (XPS). According to the experimental results, a possible mechanism for the formation of Nb doped brookite TiO2 nanosheets was proposed. Furthermore, Nb doped brookite TiO2 nanosheets were used as an anode material for the Li-ion intercalation reaction and it was found that their electronic/ionic conductivity was improved. At the same time, the cell made of Nb doped brookite TiO2 nanosheets also exhibited enhanced lithium-ion intercalation properties. For instance, this material displayed reversible capacities of 119.7 and 104.6 mA h g−1 at 5 C after 100 and 500 cycles, respectively.

This paper is concerned with a three dimensional diffusive Lotka-Volterra system which is combined with cooperative-competitive interactions between the three species. By using the method of super-sub solutions and comparison principle with cross iteration, some results on the asymptotic spreading speed of the system are established under certain assumptions on the parameters appearing in the system.

The Pirani and Dimeglio scoring systems both have excellent inter-observer and intra-observer reliability, but no research has been conducted to determine their inter-observer reliability and their relationship at different levels of deformity. A total of 173 idiopathic clubfoot cases were reviewed using Pirani and Dimeglio scoring systems, and the number of casts needed was also recorded. For clubfeet with a cast number equal to 2 or 7 and 8, the inter-observer reliability of the two scoring systems was poor or moderate, and there was no correlation between the two scoring systems. There was also no correlation between the Dimeglio scoring score with the number of casts for grade II or IV clubfeet. A binary regression of the number of casts on initial Pirani or Dimeglio scores showed that there was a Quadratic or Cubic relation between the scores and the cast numbers. In conclusion, in the case of mild and very severe clubfoot deformity, the interobserver reliability and its ability to predict the number of casts needed for clubfoot deformity correction was poor. A more objective evaluation system may be required.

Sirtuin 5 (SIRT5) is a member of the NAD+‑dependent class III protein deacetylases. Although it is known that SIRT5 deacetylates and activates urate oxidase in the liver mitochondria of mice, the mechanism of SIRT5 in the proliferation of hepatocellular carcinoma (HCC) remains to be fully elucidated. The present study investigated the expression and functional significance of SIRT5 in HCC, and examined the relevant mechanism. SIRT5 was found to be upregulated in HCC tissues and cell lines, and the higher expression of SIRT5 indicated poorer overall survival. Reverse transcription‑quantitative polymerase chain reaction analysis, western blot analysis, chromatin immunoprecipitation analysis, and luciferase reporter gene, proliferation and Transwell assays were performed to elucidate the function of SIRT5 in the regulation of cell proliferation and invasion in human HCC. Functionally, it was observed that the inhibition of SIRT5 significantly suppressed HCC cell proliferation and invasion, whereas the overexpression of SIRT5 promoted HCC cell proliferation and invasion in vitro. E2F transcription factor 1 (E2F1) was identified as a novel target gene of SIRT5. In addition, the knockdown of SIRT5 induced the expression of E2F1, and the knockdown of E2F1 in HCC cells partially reversed the effect of SIRT5 in promoting cell proliferation and invasion. Collectively, these data provide the first evidence, to the best of our knowledge, that the SIRT5 gene has an important regulatory role in liver carcinogenesis, and may function as a novel potential therapeutic target for HCC.

The economic transformation needs the support of the micro level of enterprise transformation. As one of the main bodies of the market; Hi-Tech SMEs play the most active part in the market, promoting economic transformation. Current study on enterprise transformation mainly concentrated in manufacturing; there are few studies on the impact of entrepreneurial behavior on the success or failure of transformation of Hi-Tech SMEs. For this reason, this paper conducts a case study of Qi Wei Te solar energy corporation on this issue. The study finds that enterprise transformation follows the transition of entrepreneur’s behavior and the entrepreneur’s behavior affect the success or failure of the transformation. Magnificent dreams and business experience are the starting point of enterprise transformation. Learning behavior runs through the whole process of enterprise development. The inertia of thinking is the root of the enterprise unable to adapt to the environment. Network building behavior is adjusted, and then the internal and external social networks are adjusted to provide the guarantee for the successful transformation. On the basis of these, the paper puts forward the behavior pattern of entrepreneurs in the process of transformation.

Study on frog swimming mechanism is an interesting topic, and a frog inspired robot has been designed with the pneumatic muscles as the driver. To improve the design and trajectory planning, the optimization of the robot was studied in this paper. For the robot structure, the limb size was optimized in ADAMS and joint parameters of the bionic robot are optimized by particle swarm optimization (PSO) method. Meanwhile, the trajectory during propulsive phase is also optimized in Matlab. Simulations in ADAMS verified the feasibility of the proposed optimization for the frog inspired robot.

Although lithium-sulfur (Li-S) batteries are among the most promising rechargeable batteries in the field of energy-storage devices, their poor cycling performance restricts their potential applications. Polar materials can improve the cycling stability owing to their inherent strong chemical interaction with polysulfides. Herein, novel rutile TiO

Many legged robots have compliant mechanisms in the distal segments of their legs called distal compliance. One important function of such characteristic is to buffer landing impact at touchdown. However, there is still no general design strategy for it. In particular, nonlinear compliance behaviors are supposed to be more beneficial than linear ones, yet it is open what type of nonlinearity is a good fit. From this perspective, we used a simple spring–mass model performing free drop to investigate the design principles of distal compliance. The model includes damping and preload in spring and realistic limitations on spring compression, therefore gives a straightforward correspondence with actual hardware systems. We confirmed the benefits of using distal compliance over purely stiff structures, in terms of landing impact buffering. By assessing the relative influences of a variety of compliance configurations through numerical simulations, we found that for compliance behaviors of the same average stiffness, nonlinearities had little effect on the impact magnitude (

This thesis proposes a path planning method of obstacle and singularity avoidance with synergistic effect for redundant robot. By analyzing robot configuration, it proposes an improved method to calculate real-time minimum distance. At first, it screens out the connecting rod which might collide. Then, it calculates the distance by coordinate variation method and took the minimum value. At last, it obtains the real-time minimum distance. By introducing two obstacle avoidance parameters related to the real-time minimum distance, this thesis uses the self-motion of redundant kinematic chain in null space to complete obstacle avoidance. Also, it applies DLS method to complete singularity avoidance optimization to the obstacle avoidance algorithm. It solves the problem of excessive joint velocity close to singularity configuration. In the end, this thesis verifies the effectiveness of the algorithm by conducting simulation experiment on a plane 3R redundant robot.

In this research, we mainly studied the Site selection problem of cold chain logistics in northwest of China. In the first place, we counted the demands of cold chain products in northwest territories, and then classified it into the Site selection problem in five provinces in northwest territories(Xinjiang, Qinghai, Gansu, Ningxia, Shanxi); Next, we used the Center of gravity Method to select initial location; Finally, we established the location of distribution by using Analytic Hierarchy Process (AHP)and fuzzy comprehensive evaluation method. Comparing with the traditional method, this method not only considered the cost of transportation and distance, but also deliberated the physical condition, social environment and economics condition which associated with Site selection problem.In this research, we mainly studied the Site selection problem of cold chain logistics in northwest of China. In the first place, we counted the demands of cold chain products in northwest territories, and then classified it into the Site selection problem in five provinces in northwest territories(Xinjiang, Qinghai, Gansu, Ningxia, Shanxi); Next, we used the Center of gravity Method to select initial location; Finally, we established the location of distribution by using Analytic Hierarchy Process (AHP)and fuzzy comprehensive evaluation method. Comparing with the traditional method, this method not only considered the cost of transportation and distance, but also deliberated the physical condition, social environment and economics condition which associated with Site selection problem.

This paper reports the design methodology and control strategy in the development of a novel hexapod robot HITCR-II that is suitable for walking on unstructured terrain. First, the entire sensor system is designed to equip the robot with the perception of external environment and its internal states. The structure parameters are optimized for improving the dexterity of the robot. Second, a foot-force distribution model and a compensation model are built to achieve posture control. The two models are capable of effectively improving the stability of hexapod walking on unstructured terrain. Finally, the Posture Control strategy based on Force Distribution and Compensation (PCFDC) is applied to the HITCR-II hexapod robot. The experimental results show that the robot can effectively restrain the vibration of trunk and keep stable while walking and crossing over the unstructured terrains.

Aiming at the different characteristics of the infrared image and visible light image, the paper proposed a kind of fusion algorithm for the infrared image and visible light image based on non-subsampled contourlet transform. Firstly, the source images are made multiscale and multi-direction decomposition by using non-subsampled contourlet transform (NSCT). Secondly, to decomposed low frequency subband, a decision-making value with regional energy and variance is constructed and used in fusing the coefficients by choosing larger decision-making value. And for the decomposed high frequency subband, different fusion rules are employed for different levels. The fusion rule of selecting large absolute value of pixel is used for the highest level, and the fusion rule of selecting large regional variance based on regional energy matching degree is used to fuse the other levels. Finally, the final fused image is reconstructed by using the non-subsampled contourlet inverse transform. The experimental results have shown that the proposed algorithm can get more detail information and can exhibit better fusion performance. Key words: Fusion algorithm, regional energy matching degree, image fusion, non-subsampled contourlet transform, infrared image, visible light image, shift invariant.

Biological inspiration has spawned a wealth of solutions to both mechanical design and control schemes in the efforts to develop agile legged machines. This paper presents a compliant leg mechanism for a small six-legged robot, HITCR-II, based on abstracted anatomy from insect legs. Kinematic structure, relative proportion of leg segment lengths and actuation system were analyzed in consideration of anatomical structure as well as muscle system of insect legs and desired mobility. A spring based passive compliance mechanism inspired by musculoskeletal structures of biological systems was integrated into distal segment of the leg to soften foot impact on touchdown. In addition, an efficient locomotion planner capable of generating natural movements for the legs during swing phase was proposed. The problem of leg swing was formulated as an optimal control procedure that satisfies a series of locomotion task terms while minimizing a biologically-based objective function, which was solved by a Gauss Pseudospectral Method (GPM) based numerical technique. We applied this swing generation algorithm to both a simulation platform and a robot prototype. Results show that the proposed leg structure and swing planner are able to successfully perform effective swing movements on rugged terrains.

In this study, the change of tumors' chemical composition in the temperature range of 20 ~70 °C is quantified for photothermal tumor therapy by photoacoustic spectroscopy (PAS) with the wavelengths of 700~1000 nm. Based on the measured photoacoustic signals, two absorption peaks at the wavelengths of 750 nm and 950 nm are identified. It is also observed that high temperature (>55 °C) is able to induce the physical and chemical degeneration of tumors. According to the in vitro tests, a new chemical species, met-hemoglobin, which is absent in normal blood, is generated at high temperature with enhanced near-infrared absorption.

Measurement of light distribution in biological tissue contributes to selecting strategy and optimizing dose for biomedical application. In this letter, a photoacoustic method combined with Monte Carlo simulation was used to estimate the three-dimensional light distribution in biological tissue. The light distribution was produced by a cylindrical diffuser which interposed into tissues. The light profiles obtained by the method were compared to those detected by photo diodes. The experimental results demonstrate the feasibility of this method. The approach can play a significant role for photo-dosimetry in biomedical phototherapy.

In the present work, a one-step synthetic route is developed for fabricating hierarchical anatase TiO2 microspheres for the first time. These microspheres are composed of ultrathin rod-like structures in the radial direction, in which ultrathin rods consisted of tiny octahedra via a growth model of oriented attachment. Based on XRD and electron microscopic analyses, a mechanism for the growth of the microspheres is proposed. This material displays a large capacity of 157.3 mA h g−1 at 1 C after 200 cycles and also exhibits high rate performance and excellent cycling stability. These high performance characteristics may be due to the intrinsic characteristics of the hierarchical porous anatase TiO2 microspheres, in which the porous structure can permit facile diffusion of the electrolyte. They can also enhance the contact between the electrode surface and the electrolyte, while the ultrathin rods can shorten the transport distance of Li-ions and electrons during electrochemical cycling. At the same, the porous microsphere can also accommodate volume changes in the charge–discharge process.

Hierarchically porous rutile TiO2 microspheres composed of nanorods were fabricated by using a facile synthetic route. These materials were characterized by X-ray diffraction (XRD), N2 adsorption–desorption, and scanning and transmission electron microscopy (SEM and TEM). Based on a series of experimental results, a self-assembly process for the formation of the hierarchical microspheres was also proposed. Furthermore, the hierarchically porous rutile TiO2 microspheres were used as the negative electrode material in lithium-ion batteries (LIBs) and demonstrated a large reversible charge–discharge capacity of 160.4 mA h g−1 after 100 cycles at 1 C, which was much greater than commercial rutile TiO2 under the same conditions, indicating that these materials had excellent cycling stability and high rate performance.

Liu, Y.; Li, X., and Hou, X., 2020. Spatiotemporal changes to the river channel and shoreline of the Yellow River Delta during a 40-year period (1976–2017). Journal of Coastal Research, 36(1), 128–138. Coconut Creek (Florida), ISSN 0749-0208.The coastal zone is a sensitive region affected by both human activities and climate change. The shoreline is a crucial component of coastal zones. Shoreline monitoring research has a vital role in managing and protecting coastal ecosystems and communities. This study focuses on measurements of morphological change in the Yellow River channel and the Yellow River Delta (YRD) shoreline during a 40-year period. The lower reaches of the Yellow River continuously changed because of silting, stretching, lifting, swinging, and avulsion, to ultimately, changing course. The location of the mouth of the Yellow River was directly influenced by the swinging and the artificial avulsion. Overall, the shoreline expanded seaward at a decreasing rate over time, but it exhibited distinctively different patterns in two subregions (Diaokou and Qingshuigou). The shoreline in Diaokou displayed a trend of retreating inland, whereas the shoreline in Qingshuigou expanded rapidly towards the sea. The rate of change was greatest near the river mouth. An upward trend in the shape index was found across the YRD and its subregions, reflecting the shoreline becoming more complex over time. Human activities will become an increasingly important factor affecting the development and evolution of the YRD. This study should be useful for coastal engineers, coastal managers, and policy makers in the YRD.

The photosensitizer (PS) as photodynamic therapy (PDT) agent, can also serve as the contrast agent for dual-modal fluorescence imaging (FLI) and photoacoustic imaging (PAI) for precise cancer theranostics. In this study, the PAI capability of commercial PS, benzoporphyrin derivative monoacid ring-A (BPD) were examined and compared with that from the other PSs and dyes such as TPPS4, Cy5 dye and ICG. We discovered that BPD exhibited its advantage as contrast agent for PAI. Meanwhile, BPD can also serve as the contrast agent for enhanced FLI. In particular, the PEGylated nanoliposome (PNL) encapsulated BPD (LBPD) was produced for contrast enhanced dual-modal FLI and PAI and imaging-guided high-efficiency PDT. Enhanced FLI and PAI results demonstrated the significant accumulation of LBPD both within and among individual tumor during 24[Formula: see text]h monitoring for in vivo experiment tests. In-vitro and in-vivo PDT tests were also performed, which showed that LBPD have higher PDT efficiency and can easily break the blood vessel of tumor tissues as compared to that from BPD. It was discovered that LBPD has great potentials as a diagnosis and treatment agent for dual-modal FLI and PAI-guided PDT of cancer.