期刊文献+
共找到82篇文章
< 1 2 5 >
每页显示 20 50 100
Coupling of Adhesion and Anti‑Freezing Properties in Hydrogel Electrolytes for Low‑Temperature Aqueous‑Based Hybrid Capacitors
1
作者 Jingya Nan Yue Sun +9 位作者 Fusheng Yang Yijing Zhang Yuxi Li zihao wang Chuchu wang Dingkun wang Fuxiang Chu Chunpeng wang Tianyu Zhu Jianchun Jiang 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第2期15-31,共17页
Solid-state zinc-ion capacitors are emerging as promising candidates for large-scale energy storage owing to improved safety,mechanical and thermal stability and easy-to-direct stacking.Hydrogel electrolytes are appea... Solid-state zinc-ion capacitors are emerging as promising candidates for large-scale energy storage owing to improved safety,mechanical and thermal stability and easy-to-direct stacking.Hydrogel electrolytes are appealing solid-state electrolytes because of eco-friendliness,high conductivity and intrinsic flexibility.However,the electrolyte/electrode interfacial contact and anti-freezing properties of current hydrogel electrolytes are still challenging for practical applications of zinc-ion capacitors.Here,we report a class of hydrogel electrolytes that couple high interfacial adhesion and anti-freezing performance.The synergy of tough hydrogel matrix and chemical anchorage enables a well-adhered interface between hydrogel electrolyte and electrode.Meanwhile,the cooperative solvation of ZnCl2 and LiCl hybrid salts renders the hydrogel electrolyte high ionic conductivity and mechanical elasticity simultaneously at low temperatures.More significantly,the Zn||carbon nanotubes hybrid capacitor based on this hydrogel electrolyte exhibits low-temperature capacitive performance,delivering high-energy density of 39 Wh kg^(-1)at-60°C with capacity retention of 98.7%over 10,000 cycles.With the benefits of the well-adhered electrolyte/electrode interface and the anti-freezing hydrogel electrolyte,the Zn/Li hybrid capacitor is able to accommodate dynamic deformations and function well under 1000 tension cycles even at-60°C.This work provides a powerful strategy for enabling stable operation of low-temperature zinc-ion capacitors. 展开更多
关键词 Interfacial adhesion ANTI-FREEZING Hydrogel electrolytes Low-temperature hybrid capacitors Dynamic deformati
下载PDF
A Path Planning Algorithm Based on Improved RRT Sampling Region
2
作者 Xiangkui Jiang zihao wang Chao Dong 《Computers, Materials & Continua》 SCIE EI 2024年第9期4303-4323,共21页
For the problem of slow search and tortuous paths in the Rapidly Exploring Random Tree(RRT)algorithm,a feedback-biased sampling RRT,called FS-RRT,is proposedbasedon RRT.Firstly,toimprove the samplingefficiency of RRT ... For the problem of slow search and tortuous paths in the Rapidly Exploring Random Tree(RRT)algorithm,a feedback-biased sampling RRT,called FS-RRT,is proposedbasedon RRT.Firstly,toimprove the samplingefficiency of RRT to shorten the search time,the search area of the randomtree is restricted to improve the sampling efficiency.Secondly,to obtain better information about obstacles to shorten the path length,a feedback-biased sampling strategy is used instead of the traditional random sampling,the collision of the expanding node with an obstacle generates feedback information so that the next expanding node avoids expanding within a specific angle range.Thirdly,this paper proposes using the inverse optimization strategy to remove redundancy points from the initial path,making the path shorter and more accurate.Finally,to satisfy the smooth operation of the robot in practice,auxiliary points are used to optimize the cubic Bezier curve to avoid path-crossing obstacles when using the Bezier curve optimization.The experimental results demonstrate that,compared to the traditional RRT algorithm,the proposed FS-RRT algorithm performs favorably against mainstream algorithms regarding running time,number of search iterations,and path length.Moreover,the improved algorithm also performs well in a narrow obstacle environment,and its effectiveness is further confirmed by experimental verification. 展开更多
关键词 RRT inversive optimization path planning feedback bias sampling mobile robots
下载PDF
Multi-Robot Collaborative Hunting in Cluttered Environments With Obstacle-Avoiding Voronoi Cells
3
作者 Meng Zhou zihao wang +1 位作者 Jing wang Zhengcai Cao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第7期1643-1655,共13页
This work proposes an online collaborative hunting strategy for multi-robot systems based on obstacle-avoiding Voronoi cells in a complex dynamic environment. This involves firstly designing the construction method us... This work proposes an online collaborative hunting strategy for multi-robot systems based on obstacle-avoiding Voronoi cells in a complex dynamic environment. This involves firstly designing the construction method using a support vector machine(SVM) based on the definition of buffered Voronoi cells(BVCs). Based on the safe collision-free region of the robots, the boundary weights between the robots and the obstacles are dynamically updated such that the robots are tangent to the buffered Voronoi safety areas without intersecting with the obstacles. Then, the robots are controlled to move within their own buffered Voronoi safety area to achieve collision-avoidance with other robots and obstacles. The next step involves proposing a hunting method that optimizes collaboration between the pursuers and evaders. Some hunting points are generated and distributed evenly around a circle. Next, the pursuers are assigned to match the optimal points based on the Hungarian algorithm.Then, a hunting controller is designed to improve the containment capability and minimize containment time based on collision risk. Finally, simulation results have demonstrated that the proposed cooperative hunting method is more competitive in terms of time and travel distance. 展开更多
关键词 Dynamic obstacle avoidance multi-robot collaborative hunting obstacle-avoiding Voronoi cells task allocation
下载PDF
Position-aware pushing and grasping synergy with deep reinforcement learning in clutter
4
作者 Min Zhao Guoyu Zuo +3 位作者 Shuangyue Yu Daoxiong Gong zihao wang Ouattara Sie 《CAAI Transactions on Intelligence Technology》 SCIE EI 2024年第3期738-755,共18页
The positional information of objects is crucial to enable robots to perform grasping and pushing manipulations in clutter.To effectively perform grasping and pushing manipu-lations,robots need to perceive the positio... The positional information of objects is crucial to enable robots to perform grasping and pushing manipulations in clutter.To effectively perform grasping and pushing manipu-lations,robots need to perceive the position information of objects,including the co-ordinates and spatial relationship between objects(e.g.,proximity,adjacency).The authors propose an end-to-end position-aware deep Q-learning framework to achieve efficient collaborative pushing and grasping in clutter.Specifically,a pair of conjugate pushing and grasping attention modules are proposed to capture the position information of objects and generate high-quality affordance maps of operating positions with features of pushing and grasping operations.In addition,the authors propose an object isolation metric and clutter metric based on instance segmentation to measure the spatial re-lationships between objects in cluttered environments.To further enhance the perception capacity of position information of the objects,the authors associate the change in the object isolation metric and clutter metric in cluttered environment before and after performing the action with reward function.A series of experiments are carried out in simulation and real-world which indicate that the method improves sample efficiency,task completion rate,grasping success rate and action efficiency compared to state-of-the-art end-to-end methods.Noted that the authors’system can be robustly applied to real-world use and extended to novel objects.Supplementary material is available at https://youtu.be/NhG\_k5v3NnM}{https://youtu.be/NhG\_k5v3NnM. 展开更多
关键词 deep learning deep neural networks intelligent robots
下载PDF
Analysis of Influencing Factors on Fruit Consumption of Urban and Rural Residents in Beijing
5
作者 zihao wang Rao CHEN Weimin YANG 《Asian Agricultural Research》 2024年第6期1-4,10,共5页
In light of the rapid expansion of China s economy,there has been a notable shift in the consumption patterns of urban and rural residents.This is evident in the increased consumption of agricultural products,with fru... In light of the rapid expansion of China s economy,there has been a notable shift in the consumption patterns of urban and rural residents.This is evident in the increased consumption of agricultural products,with fruit consumption representing a particularly pronounced trend.The 2023 Beijing Consumption Statistics indicate that demand for fruit is increasing,accompanied by heightened competition for quality and brands.The paper is based on research that examines the current situation of fruit consumption among urban and rural residents in Beijing.The results indicate that when urban and rural residents in Beijing purchase fruits,price is the most significant factor influencing fruit consumption.Taste,appearance,and variety are also considered to be important influencing factors,while the influence of factors such as fruit type,consumption pattern,and fruit brand is relatively minor. 展开更多
关键词 URBAN and RURAL RESIDENTS of BEIJING FRUIT CONSUMPTION Influencing factor CONSUMPTION behavior
下载PDF
Fracture of films caused by uniaxial tensions:a numerical model 被引量:1
6
作者 Chenxue JIA zihao wang +2 位作者 Donghui ZHANG Taihua ZHANG Xianhong MENG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第12期2093-2108,共16页
Surface cracks are commonly observed in coatings and films.When structures with coatings are subject to stretching,opening mode cracks are likely to form on the surface,which may further lead to other forms of damage,... Surface cracks are commonly observed in coatings and films.When structures with coatings are subject to stretching,opening mode cracks are likely to form on the surface,which may further lead to other forms of damage,such as interfacial delamination and substrate damage.Possible crack forms include cracks extending towards the interface and channeling across the film.In this paper,a two-dimensional numerical model is proposed to obtain the structural strain energy at arbitrary crack lengths for bilayer structures under uniaxial tension.The energy release rate and structural stress intensity factors can be obtained accordingly,and the effects of geometry and material features on fracture characteristics are investigated,with most crack patterns being confirmed as unstable.The proposed model can also facilitate the analysis of the stress distribution in periodic crack patterns of films.The results from the numerical model are compared with those obtained by the finite element method(FEM),and the accuracy of the theoretical results is demonstrated. 展开更多
关键词 surface crack numerical model stress intensity factor periodic crack finite element method(FEM)
下载PDF
跨组织线粒体应激信号交流调控机体衰老研究进展
7
作者 张茜 王子豪 田烨 《遗传》 CAS CSCD 北大核心 2023年第3期187-197,共11页
线粒体内蛋白质稳态的平衡对于细胞正常的生理功能非常关键。线粒体蛋白稳态失衡时,细胞会启动应激反应机制,即线粒体未折叠蛋白反应(mitochondrial unfolded protein response,UPR^(mt)),修复线粒体功能,平衡细胞内稳态。尽管线粒体的... 线粒体内蛋白质稳态的平衡对于细胞正常的生理功能非常关键。线粒体蛋白稳态失衡时,细胞会启动应激反应机制,即线粒体未折叠蛋白反应(mitochondrial unfolded protein response,UPR^(mt)),修复线粒体功能,平衡细胞内稳态。尽管线粒体的严重损伤对机体是有害的,但在线虫(Caenorhabditis elegans)、果蝇(Drosophila melanogaste)及小鼠(Mus musculus)中都有研究表明线粒体的轻微损伤可以通过激活UPR^(mt),促进寿命延长。有趣的是,在没有直接经历线粒体损伤的细胞或组织中,UPR^(mt)也能以非自主方式被诱导。不同组织间可以通过名为“mitokine”的细胞因子进行UPR^(mt)的跨组织调控,系统性地协调机体整体的压力适应能力和抗衰老能力。该调控机制与衰老相关神经退行性疾病、癌症等多种疾病密切相关,近年来有关研究与日俱增。本文系统总结了线粒体应激及其组织间通讯的机制,并介绍了跨组织线粒体应激交流信号“mitokine”调控衰老进程的最新研究进展,以期为跨组织信号调控和机体衰老等研究提供参考。 展开更多
关键词 线粒体未折叠蛋白反应 蛋白稳态 跨组织调控 衰老
下载PDF
Fault Analysis of Wind Power Rolling Bearing Based on EMD Feature Extraction 被引量:12
8
作者 Debiao Meng Hongtao wang +3 位作者 Shiyuan Yang Zhiyuan Lv Zhengguo Hu zihao wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第1期543-558,共16页
In a wind turbine,the rolling bearing is the critical component.However,it has a high failure rate.Therefore,the failure analysis and fault diagnosis of wind power rolling bearings are very important to ensure the hig... In a wind turbine,the rolling bearing is the critical component.However,it has a high failure rate.Therefore,the failure analysis and fault diagnosis of wind power rolling bearings are very important to ensure the high reliability and safety of wind power equipment.In this study,the failure form and the corresponding reason for the failure are discussed firstly.Then,the natural frequency and the characteristic frequency are analyzed.The Empirical Mode Decomposition(EMD)algorithm is used to extract the characteristics of the vibration signal of the rolling bearing.Moreover,the eigenmode function is obtained and then filtered by the kurtosis criterion.Consequently,the relationship between the actual fault frequency spectrum and the theoretical fault frequency can be obtained.Then the fault analysis is performed.To enhance the accuracy of fault diagnosis,based on the previous feature extraction and the time-frequency domain feature extraction of the data after EMD decomposition processing,four different classifiers are added to diagnose and classify the fault status of rolling bearings and compare them with four different classifiers. 展开更多
关键词 Wind turbine rolling bearing fault diagnosis empirical mode decomposition
下载PDF
Selective synthesis of triacetin from glycerol catalyzed by HZSM-5/MCM-41 micro/mesoporous molecular sieve 被引量:3
9
作者 Jiangyong Liu zihao wang +3 位作者 Yunlin Sun Ruiqi Jian Panming jian Dan wang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第5期1073-1078,共6页
HZSM-5/MCM-41 molecular sieve (H-ZM) catalysts with well-defined micro/mesoporous structures were synthesized and showed high performance for selective synthesis of triacetin via the esterification reaction of glycero... HZSM-5/MCM-41 molecular sieve (H-ZM) catalysts with well-defined micro/mesoporous structures were synthesized and showed high performance for selective synthesis of triacetin via the esterification reaction of glycerol with acetic acid. The conversion of glycerol was demonstrated to be 100% and the triacetin selectivity was over 91%, which can be attributed to the synergistic effect regarding suitable acidic property, excellent diffusion efficiency and good stability derived from the combined advantages of microporous molecular sieve HZSM-5 and mesoporous molecular sieve MCM-41. 展开更多
关键词 MESOSCALE Porous materials Molecular SIEVE TRIACETIN GLYCEROL ESTERIFICATION
下载PDF
Fabrication of TiO_2(B)/anatase heterophase junctions in nanowires via a surface-preferred phase transformation process for enhanced photocatalytic activity 被引量:4
10
作者 Yilan wang Wan Zhang +4 位作者 zihao wang Yimeng Cao Jiami Feng Zenglin wang Yi Ma 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第9期1500-1510,共11页
Heterojunction fabrication is one of the most effective strategies for enhancing the photocatalytic performance of semiconductor photocatalysts. Here, TiO2(B)/anatase nanowires with interfacial heterostructures were... Heterojunction fabrication is one of the most effective strategies for enhancing the photocatalytic performance of semiconductor photocatalysts. Here, TiO2(B)/anatase nanowires with interfacial heterostructures were prepared through a three-step synthesis method, including hydrothermal treatment, H+ exchange, and annealing. The phase structures of the nanowires in the bulk and on the surface during the annealing process were monitored by XRD and UV-Raman spectroscopy, respectively. SEM and TEM results indicate that the TiO2(B) nanowires partially collapse and transform into anatase during the annealing process and the heterophase junction structure is formed simultaneously. On the basis of the phase structure together with morphology data, a phase-transformation mechanism was proposed. Photocatalytic activity was evaluated by hydrogen production and pollutant-degradation assays. The optimized structure of the photocatalyst contains 24% TiO2(B) in the bulk and 100% anatase on the surface. The charge-carrier behavior during the photocatalytic process was investigated by photocurrent, electrochemical impedance spectroscopy(EIS), and photoluminescence(PL) spectroscopy, which revealed that the heterophase-junction structure in the bulk was responsible for the highly efficient charge separation and transportation, etc.; the anatase on the surface took control of the high surface-reaction activity. 展开更多
关键词 TiO2(B)/anatase Heterophase junction Surface‐preferred Photocatalysis PHASETRANSFORMATION
下载PDF
Development of a Novel Feedforward Neural Network Model Based on Controllable Parameters for Predicting Effluent Total Nitrogen 被引量:4
11
作者 zihao Zhao zihao wang +5 位作者 Jialuo Yuan Jun Ma Zheling He Yilan Xu Xiaojia Shen Liang Zhu 《Engineering》 SCIE EI 2021年第2期195-202,共8页
The problem of effluent total nitrogen(TN)at most of the wastewater treatment plants(WWTPs)in China is important for meeting the related water quality standards,even under the condition of high energy consumption.To a... The problem of effluent total nitrogen(TN)at most of the wastewater treatment plants(WWTPs)in China is important for meeting the related water quality standards,even under the condition of high energy consumption.To achieve better prediction and control of effluent TN concentration,an efficient prediction model,based on controllable operation parameters,was constructed in a sequencing batch reactor process.Compared with previous models,this model has two main characteristics:①Superficial gas velocity and anoxic time are controllable operation parameters and are selected as the main input parameters instead of dissolved oxygen to improve the model controllability,and②the model prediction accuracy is improved on the basis of a feedforward neural network(FFNN)with algorithm optimization.The results demonstrated that the FFNN model was efficiently optimized by scaled conjugate gradient,and the performance was excellent compared with other models in terms of the correlation coefficient(R).The optimized FFNN model could provide an accurate prediction of effluent TN based on influent water parameters and key control parameters.This study revealed the possible application of the optimized FFNN model for the efficient removal of pollutants and lower energy consumption at most of the WWTPs. 展开更多
关键词 Feedforward neural network(FFNN) Algorithms Controllable operation parameters Sequencing batch reactor(SBR) Total nitrogen(TN)
下载PDF
Perspective:optically-pumped Ⅲ–Ⅴ quantum dot microcavity lasers via CMOS compatible patterned Si (001) substrates 被引量:2
12
作者 Wenqi Wei Qi Feng +2 位作者 zihao wang Ting wang Jianjun Zhang 《Journal of Semiconductors》 EI CAS CSCD 2019年第10期45-53,共9页
Direct epitaxial growthⅢ–Ⅴquantum dot(QD)structures on CMOS-compatible silicon substrates is considered as one of the most promising approaches to achieve low-cost and high-yield Si-based lasers for silicon photoni... Direct epitaxial growthⅢ–Ⅴquantum dot(QD)structures on CMOS-compatible silicon substrates is considered as one of the most promising approaches to achieve low-cost and high-yield Si-based lasers for silicon photonic integration.However,epitaxial growth ofⅢ–Ⅴmaterials on Si encounters the following three major challenges:high density of threading dislocations,antiphase boundaries and thermal cracks,which significantly degrade the crystal quality and potential device performance.In this review,we will focus on some recent results related to InAs/GaAs quantum dot lasers on Si(001)substrates byⅢ–Ⅴ/Ⅳhybrid epitaxial growth via(111)-faceted Si hollow structures.Moreover,by using the step-graded epitaxial growth process the emission wavelength of InAs QDs can be extended from O-band to C/L-band.High-performance InAs/GaAs QD microdisk lasers with sub-milliwatts threshold on Si(001)substrates are fabricated and characterized.The above results pave a promising path towards the on-chip lasers for optical interconnect applications. 展开更多
关键词 quantum DOTS silicon PHOTONICS EPITAXIAL growth semiconductor lasers
下载PDF
A CMOS Compatible Si Template with (111) Facets for Direct Epitaxial Growth of Ⅲ–Ⅴ Materials 被引量:2
13
作者 Wen-Qi Wei Jian-Huan wang +5 位作者 Jie-Yin Zhang Qi Feng zihao wang Hong-Xing Xu Ting wang Jian-Jun Zhang 《Chinese Physics Letters》 SCIE CAS CSCD 2020年第2期30-34,共5页
Ⅲ-Ⅴ quantum dot(QD) lasers monolithically grown on CMOS-compatible Si substrates are considered as essential components for integrated silicon photonic circuits.However,epitaxial growth of Ⅲ-Ⅴ materials on Si subs... Ⅲ-Ⅴ quantum dot(QD) lasers monolithically grown on CMOS-compatible Si substrates are considered as essential components for integrated silicon photonic circuits.However,epitaxial growth of Ⅲ-Ⅴ materials on Si substrates encounters three obstacles:mismatch defects,antiphase boundaries(APBs),and thermal cracks.We study the evolution of the structures on U-shaped trench-patterned Si(001) substrates with various trench orientations by homoepitaxy and the subsequent heteroepitaxial growth of GaAs film.The results show that the formation of(111)-faceted hollow structures on patterned Si(001) substrates with trenches oriented along [110] direction can effectively reduce the defect density and thermal stress in the GaAs/Si epilayers.The(111)-faceted silicon hollow structure can act as a promising platform for the direct growth of Ⅲ-Ⅴ materials for silicon based optoelectronic applications. 展开更多
关键词 III–V TRENCH OPTOELECTRONIC
下载PDF
微腔光梳重频调控与光谱应用 被引量:1
14
作者 王子皓 杨昌喜 鲍成英 《科学通报》 EI CAS CSCD 北大核心 2024年第12期1552-1564,共13页
利用高品质因子(高Q)微腔中材料的光学非线性可以实现高相干微腔光梳的产生,这为光频梳系统的小型化和片上集成开辟了新的可能性.对于光学频率梳,梳齿间距是光频梳的关键参数,其与产生方式相关,反过来也影响了光梳的应用.芯片化的微腔... 利用高品质因子(高Q)微腔中材料的光学非线性可以实现高相干微腔光梳的产生,这为光频梳系统的小型化和片上集成开辟了新的可能性.对于光学频率梳,梳齿间距是光频梳的关键参数,其与产生方式相关,反过来也影响了光梳的应用.芯片化的微腔光梳一般具有高重频的特点,这一特点适用于波分复用光通信、光计算、太赫兹波合成等应用.但对于精密光谱分析等应用,过大的梳齿间隔会带来光谱欠采样等问题,这一问题在中红外波段尤为明显.本文重点介绍了微腔光梳的重频调控,特别是其在光谱测量中的应用;简要分析了不同方式所产生光频梳的重频特点,以及不同应用对光梳重频的要求,特别是对双光梳测量系统;还介绍了微腔光梳与电光梳相结合的间隔光学差频(interleaved difference frequency generation,iDFG)技术,基于此技术可以实现GHz重频的中红外光梳的产生.将iDFG技术与相向传播(counter-propagating,CP)的孤子对相结合,可以实现中红外波段高相干、高分辨率的光谱测量.本文简要介绍了微腔光梳的发展,侧重于微腔光梳在光谱分析上的应用. 展开更多
关键词 微腔光梳 光学孤子 双光梳测量 重频
原文传递
Third-order polynomial model for analyzing stickup state laminated structure in flexible electronics
15
作者 Xianhong Meng zihao wang +1 位作者 Boya Liu Shuodao wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2018年第1期48-61,共14页
Laminated hard-soft integrated structures play a significant role in the fabrication and development of flexible electronics devices. Flexible electronics have advantageous characteristics such as soft and light-weigh... Laminated hard-soft integrated structures play a significant role in the fabrication and development of flexible electronics devices. Flexible electronics have advantageous characteristics such as soft and light-weight, can be folded,twisted, flipped inside-out, or be pasted onto other surfaces of arbitrary shapes. In this paper, an analytical model is presented to study the mechanics of laminated hard-soft structures in flexible electronics under a stickup state. Thirdorder polynomials are used to describe the displacement field,and the principle of virtual work is adopted to derive the governing equations and boundary conditions. The normal strain and the shear stress along the thickness direction in the bimaterial region are obtained analytically, which agree well with the results from finite element analysis. The analytical model can be used to analyze stickup state laminated structures, and can serve as a valuable reference for the failure prediction and optimal design of flexible electronics in the future. 展开更多
关键词 Flexible electronics Stickup state Third-order polynomials Virtual work principle
下载PDF
Modeling and Analyzing for a Novel Continuum Model Considering Self-Stabilizing Control on Curved Road with Slope
16
作者 Li Lei zihao wang Yong Wu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第6期1815-1830,共16页
It is essential to fully understand master the traffic characteristics of the self-stabilizing control effect and roadcharacteristics to ensure the regular operation of transportation. Traffic flow on curved roads and... It is essential to fully understand master the traffic characteristics of the self-stabilizing control effect and roadcharacteristics to ensure the regular operation of transportation. Traffic flow on curved roads and slopes is irregularand more complicated than that on the straight road. However, most of the research only considers the effect ofself-stabilizing in the straight road. This study attempts to bridge this deficiency from the following three aspects.First, we review the potential influencing factors of traffic flow stability, which are related to the vehicle’s steadyvelocity, history velocity, and the turn radius of the road and the slope of the road. Based on the above review,an extended continuum model accounting for the self-stabilizing effect on a curved road with slope is proposed.Second, the linear stability criterion of the new model is derived by applying linear stability theory, and the neutralstability curve is obtained in detail. The modified KdV equation describing the evolution characteristics of trafficcongestion is derived by using the nonlinear analysis method. Upon the theoretical analysis, the third aspectfocuses on simulating the self-stabilizing effect under different slopes and radius, which demonstrates that theself-stabilizing effect is conducive to reducing congestion of the curved road with slope. 展开更多
关键词 Traffic flow KdV equation self-stabilizing effect gradient highway curved road
下载PDF
Analytical study of wrinkling in thin-film-on-elastomer system with finite substrate thickness
17
作者 Xianhong MENG Guanyu LIU +1 位作者 zihao wang Shuodao wang 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2017年第4期469-478,共10页
Surface wrinkling, a film bonded on a pre-strained elastomeric substrate can form periodic wrinkling patterns, is a common phenomenon in daily life. In existing theoretical models, the film is much thinner than the su... Surface wrinkling, a film bonded on a pre-strained elastomeric substrate can form periodic wrinkling patterns, is a common phenomenon in daily life. In existing theoretical models, the film is much thinner than the substrate so that the substrate can be considered to be elastomeric with infinite thickness. In this paper, the effect of finite substrate thickness is analyzed theoretically for free boundary condition cases. Based on the minimum potential energy principle, a theoretical model is established, and the wave length and amplitude of the wrinkling pattern are obtained. When the thickness of the substrate is more than 200 times larger than the thickness of the film, the results of this study agree well with the results obtained from the previous models for infinite substrate thickness. However, for thin substrates, the effect of finite substrate thickness becomes significant. The model given in this paper accurately describes the effect of finite substrate thickness, providing important design guidelines for future thin-film-on-substrate systems such as stretchable electronic devices. 展开更多
关键词 WRINKLING finite substrate thickness theoretical mechanics model
下载PDF
Scavenging Effects of Kaolin on Fine Ash Formation during Zhundong Coal Combustion
18
作者 Fangqi Liu Xianpeng Zeng +2 位作者 Yimin Xia zihao wang Dunxi Yu 《Energy Engineering》 EI 2021年第3期459-471,共13页
The previous work found that the additive kaolin could scavenge not only sodium(Na)but also calcium(Ca)and magnesium(Mg),which is the important ash fluxing agents in low rank coal combustion.Such scavenging effects of... The previous work found that the additive kaolin could scavenge not only sodium(Na)but also calcium(Ca)and magnesium(Mg),which is the important ash fluxing agents in low rank coal combustion.Such scavenging effects of kaolin on fine ash formation were studied in the present work.A typical Zhundong coal and its blends with kaolin at dosages of 1,2 and 4 wt%were combusted in an electrically heated drop tube furnace(DTF)at 1300℃.The fine ashes generated were collected and size segregated by a low pressure impactor(LPI).The morphology and chemical composition of fine ash were analyzed by scanning electron microscopy equipped with an energydispersive spectrometer(SEM-EDS).In addition,char/ash particles were sampled at various positions of DTF to elucidate how kaolin additive affected the fine ash formation process.The results further showed that apart from the scavenging of volatile Na,kaolin additive could also strongly scavenge the refractory Ca,Mg and Fe in the fine ash during Zhundong coal combustion,which transformed the sintered particles with irregular shape into melted spherical particles,and finally resulted in the considerable decrease of these elements in both PM_(0.4)and PM_(0.4-10)by melting and agglomeration.The close contacts between kaolin particles and coal resulted from physically mixing were a key factor responsible for the reaction of kaolin with the refractory Ca,Mg and Fe. 展开更多
关键词 Zhundong coal KAOLIN fine ash basic elements SODIUM ash deposition
下载PDF
Impacts of Torrefaction on PM_(10) Emissions from Biomass Combustion
19
作者 zihao wang Dunxi Yu +1 位作者 Jingkun Han Jianqun Wu 《Energy Engineering》 EI 2021年第5期1267-1276,共10页
Typical biomass torrefaction is a mild pyrolysis process under conditions of ordinary pressure,low temperature(200–300°C)and inert atmosphere.Torrefaction is considered to be a competitive technology for biomass... Typical biomass torrefaction is a mild pyrolysis process under conditions of ordinary pressure,low temperature(200–300°C)and inert atmosphere.Torrefaction is considered to be a competitive technology for biomass pretreatment,but its impacts on the emissions of particulate matter from biomass combustion are worthy of further study.In this paper,three kinds of biomass,i.e.,bagasse,wheat straw and sawdust were selected for torrefaction pretreatment and the impacts of torrefaction on the emission characteristics of PM_(10) from biomass combustion were investigated.The combustion experiments were carried out on a drop tube furnace.The combustion-generated particulate and bulk ash samples were collected and subjected to analyses by various techniques.The results show that torrefaction tends to result in a reduction of PM_(1)(particulates with an aerodynamic diameter less than 1μm)emissions from combustion,but the extent of reduction is dependent on biomass type.The reduction of PM_(1) from the combustion of torrefied biomass is mainly because that the torrefaction process removes some Cl and S from the biomass,thereby suppressing the release of alkali metals and the emissions of PM_(1) during the combustion process.As for PM_(1–10)(particulates with an aerodynamic diameter within 1–10μm),its emissions from combustion of torrefied biomasses are consistently reduced,compared with their untreated counterparts.This observation is primarily accounted for the enhanced particle coalescence/agglomeration in combustion of torrefied biomasses,which reduces the emissions of PM_(1–10). 展开更多
关键词 BIOMASS COMBUSTION TORREFACTION particulate matter
下载PDF
Conservative Breeding of Debao Pony in Nanning,Guangxi
20
作者 Qisheng YANG Kejun LIU +4 位作者 Shuwei CAO zihao wang Zhengyu CHEN Chunhua HUANG Lu GAN 《Asian Agricultural Research》 2020年第6期61-64,共4页
[Objectives]The development of Guangxi Debao pony is very slow,and its quantity and quality have dropped sharply.In order to reduce the deterioration of breeds and the loss of excellent genetic stallions,this study wa... [Objectives]The development of Guangxi Debao pony is very slow,and its quantity and quality have dropped sharply.In order to reduce the deterioration of breeds and the loss of excellent genetic stallions,this study was conducted.[Methods]Modern biological reproduction technology was adopted to protect,breed,develop,purify and rejuvenate the germplasm resources of Debao pony,and a conservation farm was constructed for Debao pony to speed up the development of the industrialization of ponies.[Results]Debao pony is characterized with strong disease resistance and strong adaptability to other places,and the growth indicators are basically consistent with the origin,which is conducive to market promotion.[Conclusions]The start of Guangxi Debao pony ex-situ conservation project will accelerate the development of pony industrialization,and it has particularly important practical significance. 展开更多
关键词 Debao pony Ex-situ FEEDING EXPERIMENT
下载PDF
上一页 1 2 5 下一页 到第
使用帮助 返回顶部