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Multiconstraint adaptive three-dimensional guidance law using convex optimization

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Journal of Systems Engineering and Electronics 2020年第4期31卷 791-803页

作者： FU Shengnan LIU Xiaodong zhang wenjie XIA Qunli School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China Beijing Aerospace Automatic Control Institute Beijing 100854China School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China

The traditional guidance law only guarantees the accuracy of attacking a target. However, the look angle and acceleration constraints are indispensable in applications. A new adaptive three-dimensional proportional navigation(PN) guidance law is proposed based on convex optimization. Decomposition of the three-dimensional space is carried out to establish threedimensional kinematic engagements. The constraints and the performance index are disposed by using the convex optimization method. PN guidance gains can be obtained by solving the optimization problem. This solution is more rapid and programmatic than the traditional method and provides a foundation for future online guidance methods, which is of great value for engineering applications.

关键词： proportional navigation(PN) adaptive guidance law three-dimensional space second-order cone programming(SOCP) convex optimal control

Survey of outdoor and indoor architecture design in TVWS networks

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The Journal of China Universities of Posts and Telecommunications 2017年第6期24卷 24-38页

作者： Yang Jingmin zhang wenjie Zou Fumin School of Computer Sciences Minnan Normal University The Key Laboratory for Automotive Electronics and Electric Drive of Fujian Province Fujian University of Technology

To understand the utilizability of TV white spaces （TVWS）, a comprehensive overview of the outdoor and indoor network design over TVWS is given. The related challenges are analyzed. The potential approaches to overcoming these challenges are discussed. The open research issues are investigated. The result shows that： in the indoor scenario, the white space ratio is on average 18.4% higher than that in the outdoor scenario, which corresponds to 7.7 vacant TV channels. Both network design includes 7 key components： TV spectrum identification, access point （AP） discovery, AP association, spectrum allocation, band width adaptation, interface control and disruption handling. Due to building penetration loss, the indoor TVWS identification and AP placement should be carefully considered in the indoor scenario.

关键词： TVWS network design identification access point discovery spectrum allocation

Investigation of shunt solar cells’ currents based on equivalent circuit model

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Science China(Technological Sciences) 2016年第9期59卷 1391-1398页

作者： YI ShiGuang zhang WanHui SHEN Hui zhang wenjie LUO ZhiRong CHEN Le College of Physical Science and Technology Engineering Guangxi Colleges and Universities Key Laboratory of Complex System Optimization and Large Data Processing Yulin Normal University Yulin 537000 China Institute for Solar Energy Systems Sun Yat-sen University Guangzhou 510275 China Guangdong Testing Institute of Product Quality Supervision Foshan 528300 China

In view of the universality of the parallel connection of solar cells and their mismatch problem, in the present paper, we select two shunt solar cells (connected in parallel) as our research object, and use the equivalent one-diode circuit of the solar cell and the analysis of the two-body model. At first, the equations of current and voltage are deduced from the related electrical laws and the circuit diagram of the two solar cells connected in parallel. Then, according to the experimentally measured data of typical single-crystalline silicon solar cells (125 mm×125 mm), we select the appropriate simulation parameters. Following this, by using the photo-generated current, the shunt resistance, and the serial resistance of one of the shunt solar cells and the load resistance as independent variables, in turn, the changing characteristics of each branch current in the two shunt solar cells are numerically discussed and analyzed for these four cases for the first time. At the same time, we provide a simple physical explanation for the modeling results. Our analyses show that these parameters have different impacts on the internal currents of solar cells connected in parallel. These results provide a reference to solve the problem of connecting solar cells and to develop higher efficiency solar cells and systems. Meanwhile, the results will contribute to a better comprehension of the reasons for efficiency loss of solar cells and systems, and deepen the understanding of the electrical of solar cells behavior for high performance photovoltaic applications.

关键词： solar cells mismatch losses internal currents

Relativistic corrections of the fragmentation functions for a heavy quark to B_c and B_c~*

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Chinese Physics C 2019年第8期43卷 24-32页

作者： Deshan Yang wenjie zhang School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

In this paper, we compute the relativistic corrections of the fragmentation functions (FFs) for a heavy quark to Bc and Bc^* within the framework of non-relativistic QCD (NRQCD) factorization. The non-singlet and sing... 详细信息

关键词： perturbative QCD quarkonium NRQCD Bc

Parametric analyses of evapotranspiration landfill covers in humid regions

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Journal of Rock Mechanics and Geotechnical Engineering 2014年第4期6卷 356-365页

作者： wenjie zhang Cheng Sun Department of Civil Engineering Shanghai University MOE Key Laboratory of Soft Soil and Geoenvironmental Engineering Zhejiang University

Natural soils are more durable than almost all man-made materials. Evapotranspiration （ET） covers use vegetated soil layers to store water until it is either evaporated from the soil surface or transpired through vegetation. ETcovers rely on the water storage capacity of soil layer, rather than low permeability materials, to minimize percolation. While the use of ET covers in landfills increased over the last decade, they were mainly used in arid or semi-arid regions. At present, the use of ET covers has not been thoroughly investigated in humid areas. The purpose of this paper is to investigate the use of ETcovers in humid areas where there is an annual precipitation of more than 800 mm. Numerical analyses were carried out to investigate the influences of cover thickness, soil type, vegetation level and distribution of precipitation on performance of ET covers. Performance and applicability of capillary barriers and a new-type cover were analyzed. The results show that percolation decreases with an increasing cover thickness and an increasing vegetation level, but the increasing trend becomes unclear when certain thickness or LAI （leaf area index） is reached. Cover soil with a large capability of water storage is recommended to minimize percolation. ET covers are significantly influenced by distribution of precipitation and are more effective in areas where rainy season coincides with hot season. Capillary barriers are more efficient than monolithic covers. The new cover is better than the monolithic cover in performance and the final percolation is only 0.5% of the annual precipitation.

关键词： Evapotranspiration (ET) covers Humid areas Parametric analyses Performance

Design of integral sliding mode guidance law based on disturbance observer

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Journal of Systems Engineering and Electronics 2024年第1期35卷 186-194页

作者： ZHOU Jianping zhang wenjie ZHOU Hang LI Qiang XIA Qunli School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Informatic Engineering Mianyang Techers’CollegeMianyang 62100China Beijing Institute of Electronic System Engineering Beijing 100854China Beijing Institute of Space Long March Vehicle Beijing 100076China

With the increasing precision of guidance,the impact of autopilot dynamic characteristics and target maneuvering abilities on precision guidance is becoming more and more *** order to reduce or even eliminate the autopilot dynamic operation and the target maneuvering influence,this paper suggests a guidance system model involving a novel integral sliding mode guidance law(ISMGL).The method utilizes the dynamic characteristics and the impact angle,combined with a sliding mode surface scheme that includes the desired line-ofsight angle,line-of-sight angular rate,and second-order differential of the angular *** the same time,the evaluation scenario considere the target maneuvering in the system as the external disturbance,and the non-homogeneous disturbance observer estimate the target maneuvering as a compensation of the guidance *** proposed system’s stability is proven based on the Lyapunov stability *** simulations reveale that ISMGL effectively intercepted large maneuvering targets and present a smaller miss-distance compared with traditional linear sliding mode guidance laws and trajectory shaping guidance ***,ISMGL has a more accurate impact angle and fast convergence speed.

关键词： disturbance observer pilot dynamics integral sliding mode impact angle constraint maneuvering target

Mono-functionalized pillar[n]arenes: Syntheses, host–guest properties and applications

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Chinese Chemical Letters 2024年第1期35卷 16-30页

作者： Wenzhi Yang wenjie zhang Jingyu Chen Jiong Zhou Department of Chemistry College of SciencesNortheastern UniversityShenyang 110819China

Pillar[n]arenes are a novel class of macrocyclic hosts reported by Ogoshi and co-workers in 2008. Because of their rigid pillar structures, interesting host-guest properties and ease of modifications, pillar[n]arenes have been developed rapidly in the field of functional materials and biomedicine. The modifications of pillar[n]arenes at different positions can give them varied characteristics. Functional groups can be introduced into one position of pillar[n]arenes without changing host-guest properties of pillar[n]arenes. A series of pillar[n]arene dimers, trimers, tetramers and metallacycles can be constructed by mono-functionalized pillar[n]arenes. In this review, two synthetic methods of mono-functionalized pillar[n]arenes are summarized and structures containing mono-functionalized pillar[n]arenes are described. Furthermore, the applications of mono-functionalized pillar[n]arenes in different fields (e.g., supramolecular polymers, sensors, molecular machines, catalysis, biological applications and light-harvesting systems) are also introduced. Hopefully, this article will be useful for researchers studying pillar[n]arenes, especially the mono-functionalized pillar[n]arenes.

关键词： Pillar[n]arenes Host-guest properties Supramolecular polymer Molecular machines Biological application

A Novel Biopsy Capsule Robot Based on High-Speed Cutting Tissue

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Cyborg and Bionic Systems 2022年第1期2022卷 118-128页

作者： Zhibin Song wenjie zhang Wenhui zhang Dario Paolo Key Laboratory of Mechanism Theory and Equipment Design of the Ministry of Educat ion Tianjin UniversityTianjin 300072China Bejing Shijitan Hospital Capital Medical UniversityBeijing 100084China The BioRobotics Institute Scuola Superiore Sant'Anna56100 PisaItaly

The capsule robot(CR)is a promising endoscopic method in gastrointestinal diagnosis because of its low discomfort to *** CRs are used to acquire image information only and lack the ability to collect *** some biopsy capsule robots(BCRs)have been developed,it remains challenging to acquire the intestinal tissue while avoiding tearing and adhesion due to the flexibility of colonic *** this study,we develop a BCR with a novel sampling strategy in which soft tissue is scratched with sharp blades rotating at high speed to avoid tissue *** the BCR design,a spiral spring with prestored energy is used to release high energy within a short period of time,which is dificult for a motor or magnet to perform within a small capacity installation *** energy of the tightened spiral spring is transmitted to drive sharp blades to rotate quickly via a designed gear *** guarantee reliable sampling,a Bowden cable is used to transmit the user's manipulation to trigger the rotation of the blades,and the triggering force transmitted by the able can be monitored in real time by a force sensor installed at the manipulating end.A prototype of the proposed BCR is designed and fabricated,and its performance is tested through in vitro *** results show that the proposed BCR is effective and the size of its acquired samples satisfies dinical requirements.

关键词： Robot guarantee rotating

Construction of BiVO_(4)/BiOCl@C Z-scheme heterojunction for enhanced photoelectrochemical performance

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International Journal of Minerals,Metallurgy and Materials 2022年第11期29卷 1971-1980页

作者： Jiaxin Li Hao Yuan wenjie zhang Ruijie Zhu Zhengbo Jiao Institute of Materials for Energy and Environment College of Material Science and EngineeringQingdao UniversityQingdao 266071China

A Z-scheme heterostructure of Mo,W co-doped BiVO_(4)(Mo,W:BVO/BiOCl@C)was fabricated by a simple solid solution drying and calcination(SSDC)*** heterostructure was characterized by X-ray diffraction(XRD),Fourier transform infrared(FTIR),X-ray photoelectron spectroscopy(XPS),*** visible light irradiation,Mo,W:BVO/BiOCl@C heterostructure exhibits excellent photoelectrochemical capability compared with other as-prepared *** photocurrent density and the incident photon-to-electron conversion efficiency(IPCE)are about 5.4 and 9.0 times higher than those of pure BiVO_(4),*** enhancement of the photoelectrochemical performance can be attributed to the construct of Z-scheme system,which is deduced from the radical trapping *** Mo,W:BVO/BiOCl@C Z-scheme heterojunction enhances the visible-light absorption and reduces the recombination rate of charge *** work provides an effective strategy to construct Z-scheme photoelectrodes for the application of photoelectrochemical water splitting.

关键词： photoelectrochemical bismuth vanadate BiOCl Z-scheme carbon