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Multi-objective evolutionary optimization for geostationary orbit satellite mission planning

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Journal of Systems Engineering and Electronics 2017年第5期28卷 934-945页

作者： Jiting Li sheng zhang Xiaolu Liu Renjie He College of Information System and Management National University of Defense Technology

In the past few decades, applications of geostationary orbit (GEO) satellites have attracted increasing attention, and with the development of optical technologies, GEO optical satellites have become popular worldwide. This paper proposes a general working pattern for a GEO optical satellite, as well as a target observation mission planning model. After analyzing the requirements of users and satellite control agencies, two objectives are simultaneously considered: maximization of total profit and minimization of satellite attitude maneuver angle. An NSGA-II based multi-objective optimization algorithm is proposed, which contains some heuristic principles in the initialization phase and mutation operator, and is embedded with a traveling salesman problem (TSP) optimization. The validity and performance of the proposed method are verified by extensive numerical simulations that include several types of point target distributions.

关键词： geostationary orbit (GEO) satellitemission planning multi-objective optimization evolutionary genetic

The semi-detached binary system IU Per and its intrinsic oscillation

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Chinese Journal of Astronomy and Astrophysics 2009年第4期9卷 422-430页

作者： Xiao-Bin zhang Rong-Xian zhang Qi-sheng Li National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China

We present a long-term time-resolved photometry of the short-period eclipsing binary IU Per. It confirms the intrinsic 6 Scuti-like pulsation of the system reported by Kim et al.. With the obtained data, an orbital period study and an eclipsing light curve synthesis based on the Wilson-Devinney method were carded out. The photometric solution reveals a semi-detached configuration with the less-massive component filling its own Roche-lobe. By subtracting the eclipsing light changes from the data, we obtained the pure pulsating light curve of the mass-accreting primary component. A Fourier analysis reveals four pulsation modes with confidence larger than 99%. A mode identification based on the results of the photometric solution was made. It suggests that the star may be in radial pulsation with a fundamental period of about 0.0628 d. A brief discussion concerning the evolutionary status and the pulsation nature is finally given.

关键词： stars binaries eclipsing-stars oscillations-stars individual (IU Per)

Variations in the Biomechanics of 16 Palmar Hand Regions Related to Tomato Picking

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Journal of Bionic Engineering 2023年第1期20卷 278-290页

作者： Xue An Zhiguo Li Jun Fu Tobi Fadiji sheng zhang College of Mechanical and Electronic Engineering Northwest A&F UniversityYanglingXianyang712100China The Key Laboratory of Bionic Engineering(Ministry of Education) Jilin UniversityChangchun130012China Postharvest Research Laboratory Department of Botany and Plant BiotechnologyUniversity of JohannesburgJohannesburg2006South Africa Dynax Corporation 1-12-710FFuchuchoFuchushiTokyo183-0055Japan

The aim of this study is to systematically reveal the differences in the biomechanics of 16 hand regions related to bionic picking of *** biomechanical properties(peak loading force,elastic coefficient,maximum percentage deformation and interaction contact mechanics between human hand and tomato fruit)of each hand region were experimentally measured and covariance *** results revealed that there were significant variations in the assessed biomechanical properties between the 16 hand regions(p<0.05).The maximum pain force threshold(peak loading force in I2 region)was 5.11 times higher than the minimum pain force threshold(in Th1 region).It was found that each hand region in its normal direction can elastically deform by at least 15.30%.The elastic coefficient of the 16 hand regions ranged from 0.22 to 2.29 N mm−*** interaction contact force acting on the fruit surface was affected by the selected human factors and fruit *** obtained covariance models can quantitatively predict all of the above biomechanical properties of 16 hand *** findings were closely related to hand grasping performance during tomato picking,such as soft contact,surface interaction,stable and dexterous grasping,provided a foundation for developing a high-performance tomato-picking bionic robotic hand.

关键词： Human hand.Bionic grasping Elastic deformation Tomato picking Robotic hand

SECTION THEOREMS,COINCIDENCE THEOREMS AND INTERSECTION THEOREMS ON H-SPACES WITH APPLICATIONS

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Applied Mathematics and Mechanics(English Edition) 1993年第9期14卷 803-815页

作者： zhang Shi-sheng zhang Ying Sichuan University.Chengdu Univ.of Electronics Sci.and Tech.of China Chengdu

The purpose of this paper is to study the section theorems,coincidence theorems and intersection theorems on *** a way of application,we use these results to study the existence problems of solutions for minimax inequalities and variational *** results presented in this paper improve and extend the corresponding results in[1,3,5,6,8,9,12,14,15,17]

关键词： section theorem coincidence theorem intersection theorem,H-KKM mapping variational inequality minimax inequality

LEVEL SET METHOD FOR NUMERICAL SIMULATION OF A CAVITATION BUBBLE COLLAPSING NEAR A RIGID WALL

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Journal of Hydrodynamics 2005年第6期17卷 647-653页

作者： HUANG Jun-tao zhang Hui-sheng Department of Mechanics and Engineering Science Fudan University Shanghai 200433 China

The level set method, TVD scheme of second order upwind procedure coupled with flux limiter, ENO velocity extension procedure inside the huhble, and MAC projection algorithm were incorporated to simulate the whole collapse e volution of a cavitation bubble near a rigid wall with many complicated phenomena, such as topology distortion and shrinking, jet impact, bubble breaking into a toroidal form, and diminishing volume to zero, etc. The huhhle shape, evolution and distribution of velocity and pressure fields of the fluid during the bubble collapsing were investigated. It is found that the method is numerically stable and has good convergence property, and the results are in good agreements with those in previous work.

关键词： level set method high resolution scheme,MAC projection cavitation hubble collapse toroidal huhhle

Constructions of vector output Boolean functions with high generalized nonlinearity

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The Journal of China Universities of Posts and Telecommunications 2008年第2期15卷 77-81页

作者： KE Pin-hui zhang sheng-yuan Key Laboratory of Network Security and Cryptology Fujian Normal UniversityFujian 350007 China

Carlet et al. recently introduced generalized nonlinearity to measure the ability to resist the improved correlation attack of a vector output Boolean function. This article presents a construction of vector output Boolean fimctions with high generalized nonlinearity using the e-biased sample space. The relation between the resilient order and generalized nonlinearity is also discussed.

关键词： Boolean functions correlation attack generalizednonlinearity almost resilient functions

Global Memory Net and the development of digital image information management system: Experience and practice

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2005年第11期6卷 1216-1220页

作者： zhang sheng-qiang CHEN Ching-chih Library Sichuan University Chengdu 610064 China Graduate School of Library and Information Science Simmons College Boston MA 02115 USA

Global Memory Net (GMNet) is intended to be an effective gateway to the world cultural, historical, and heritage image collections from selected academic educational and research partners in the world. Much of these unique collections of great value to education and research are not currently accessible due to distance, form, and technical barriers. This project is to find new ways to enable users to access and exploit these significant research collections via global network. As GMNet is ending its first 5-year phase in October 2005, it has contributed substantially to the community building in digital library development by ac- commodating numerous collaborators and technical staff from various parts of the world to spend 3 to 5 months as a full-member of the GMNet team in Boston. They have come from different parts of China—such as Sichuan, Hainan, Shanghai and Xi’an; Croatia; and Hanoi, Vietnam. In addition to contribute to the overall system development and enhancement of system function- alities, they have brought valuable sample image collections of their own institutions/countries, and actually developed prototype collections as a part of GMNet. This paper describes the exciting and productive experience of the first of this visiting research group in developing the GMNet’s Version 2.0 PHP-based system under Prof. Chen’s overall supervision. It also describes both the system’s technical level structure—user/Web-based application/data, and complex functionalities with multi-collection, multi-lingual, multi-modal searching capabilities; system management capabilities; as well as provisions for user uploads and retrieval for our own projects. This Version 2.0 system is built on the Linux/Apache/PHP/MySQL platform. What is described in this paper is an actual case which has formed a base for further new development by others in the research group. It demonstrates fully the value of the synergistic collaboration among global partners for universal digital library

关键词： Global Memory Net (GMNet) Collaboration Digital image library system development Management system Cultural Historical Heritage collections

Testing long memory based on a discretely observed process

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Applied Mathematics(A Journal of Chinese Universities) 2016年第3期31卷 253-268页

作者： LIU Guang-ying zhang Xin-sheng zhang Shi-bin Department of Statistics Nanjing Audit University School of Mathematical Sciences Zhejiang University Department of Statistics Fudan University Department of Mathematics Shanghai Maritime University

In this paper we consider the problem of testing long memory for a continuous time process based on high frequency data. We provide two test statistics to distinguish between a semimartingale and a fractional integral process with jumps, where the integral is driven by a fractional Brownian motion with long memory. The small-sample performances of the statistics are evidenced by means of simulation studies. The real data analysis shows that the fractional integral process with jumps can capture the long memory of some financial data.

关键词： long memory jump fractional Brownian motion semimartingale high frequency data power variation

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张声生教授治疗脾胃病中的对立统一思想探析

时珍国医国药 2017年第7期28卷 1738-1740页

作者：张旭张声生首都医科大学附属北京中医医院北京100010

基于脾胃两脏的生理病理特性,张声生教授在脾胃病的治疗中常常体现出对立统一的学术思想,临床疗效显著。现从升降、虚实、寒热、燥湿、阴阳这几个矛盾的统一对立关系来阐述张声生教授辨治脾胃病的临床思路。

关键词：脾胃病对立统一思想临床经验