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Periodic Motion Planning and Control for Double Rotary Pendulum via Virtual Holonomic Constraints

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IEEE/CAA Journal of Automatica Sinica 2019年第1期6卷 291-298页

作者： Zeguo Wang Leonid B.Freidovich Honghua Zhang Beijing Institute of Control Engineering IEEE the Robotics and Control Laboratory (www.control.tfe.umu.se) Department of Applied Physics and ElectronicsUmea University

Periodic motion planning for an under-actuated system is rather difficult due to differential dynamic constraints imposed by passive dynamics, and it becomes more difficult for a system with higher underactuation degree, that is with a higher difference between the number of degrees of freedom and the number of independent control inputs. However, from another point of view, these constraints also mean some relation between state variables and could be used in the motion *** consider a double rotary pendulum, which has an underactuation degree 2. A novel periodic motion planning is presented based on an optimization search. A necessary condition for existence of the whole periodic trajectory is given because of the higher underactuation degree of the system. Moreover this condition is given to make virtual holonomic constraint(VHC) based control design feasible. Therefore, an initial guess for the optimization of planning a feasible periodic motion is based on this necessary condition. Then, VHCs are used for the system transformation and transverse linearization is used to design a static state feedback controller with periodic matrix function gain. The controller gain is found through another optimization procedure. The effectiveness of initial guess and performance of the closed-loop system are illustrated through numerical simulations.

关键词： Double rotary pendulum periodic motion planning under-actuated mechanical systems virtual holonomic constraint (VHC)

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Development and Application of a Modified Genetic Algorithm for Estimating Parameters in GMA Models

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Applied Mathematics 2014年第16期5卷 2447-2457页

作者： José A. Hormiga Carlos González-Alcón Néstor V. Torres Grupo de Tecnología Bioquímica Departamento de Bioquímica y Biología Molecular Facultad de Biología Universidad de La Laguna San Cristóbal de La Laguna Spain

In this work we introduce a modified version of the simple genetic algorithm (MGA) and will show the results of its application to two GMA power law models (a general theoretical branched pathway system and a mathematical model of the amplification and responsiveness of the JAK2/STAT5 pathway representing an actual, experimentally studied system). The two case studies serve to illustrate the utility and potentialities of the MGA method for concerning parameter estimation in complex models of biological significance. The analysis of the results obtained from the application of the MGA algorithm allows an evaluation of the potentialities and shortcomings of the proposed algorithm when compared with other parameter estimation algorithm such as the simple genetic algorithm (SGA) and the simulated annealing (SA). MGA shows better performance in both studied cases than SGA and SA, either in the presence or absence of noise. It is suggested that these advantages are due to the fact that the objective function definition in the MGA could include the experimental error as a weight factor, thus minimizing the distance between the data and the predicted value. Actually, MGA is slightly slower that the SGA and the SA, but this limitation is compensated by its greater efficiency in finding objective values closer to the global optimum. Finally, MGA can lead to an early local optimum, but this shortcoming may be prevented by providing a great population diversity through the insertion of different selection processes.

关键词： Parameter Estimation Genetic Algorithms GMA Models Model Calibration Inversion Methods JAK2/STAT5 Pathway Model

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汶川地震，我的北川志愿者之行

中国研究生 2008年第5期 45-47页

作者： SX04www 重庆大学研究生

一、报名踏上征程5月13日夜晚十时许,我在民主湖论坛看到一个重庆民间地震救援群,我加入了该群,报了名,这时大约是5月14日的零点。盼望着志愿者负责人能够给我打电话,我整夜没有关机。14日早晨起来后,8点没有人打

关键词：红十字会汶川地震

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Laser Remote Sensing

原子与分子物理学报 2000年第2期17卷 363-364页

作者： K.T.Lu (Atomic Engineering Corp., P.O.Box 3342, Gaithersburg, MD 20885, U.S.A.) e-mail:aec@*** WeB Site:http:∥www.*** Atomic Engineering Corp. P.O.Box 3342Gaithersburg 美国 20885

LIDAR is the first generation of laser remote sensing developed for detection of gas molecule in atmosphere. LIDAR is the abbreviated word for laser radar (laser light detection and ranging). It combines advantages of lasers ability to detect atoms and molecules and radars ability for remote sensing. The advance of technologies: tunable solid state laser (Ti sapphire, OPO etc), optical fiber, photonics imaging technique and last but not least computational techniques, have promoted the development of new types of laser remote sensors capable of detecting toxic and radioactive chemicals and metals not in gas form and not exposed in air but under ground water and subsurface soil. The high power laser is used to vaporize the target material and generate plasma. Optical fiber is often used to delivery the laser beam and to collect the emission for imaging. The combination of spectroscopy with advanced photonics imaging techniques can study both the chemical components of sample in situ under ambient conditions and spatial distribution of different chemicals in remote operation without requiring sample preparation or extensive sample handing. These new developments have greatly enlarged the horizon of traditional capability of remote sensing.

关键词： Remote Sensing Laser

技高一筹的智能型双BIOS技术：介绍承启Twin BIOS技术

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现代计算机 2000年第92期6卷 50-51页

作者： www.21pc

带你进入Windows缓冲区溢出的神秘地带

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黑客防线 2004年第5S期 21-23页

作者： www417[c4st]

小编最近迷上了缓冲区溢出漏洞的资料收集，刚开始是找网络上缓冲区溢出漏洞技术的文章，后来发现，一些帖子由于反复被转载，出现了很多遗漏，这样就让很多想学习的朋友一头雾水，而且也形不成系统，学不到扎实的技术。考虑到现在很多... 详细信息

小编最近迷上了缓冲区溢出漏洞的资料收集，刚开始是找网络上缓冲区溢出漏洞技术的文章，后来发现，一些帖子由于反复被转载，出现了很多遗漏，这样就让很多想学习的朋友一头雾水，而且也形不成系统，学不到扎实的技术。考虑到现在很多献计献策对这个感兴趣，我们将开展系列的溢出漏洞分析和讨论。本文将结合小四的《Windows 2000缓冲区溢出入门》和ipxodi的《Windows系统下的堆栈溢出》，总结作者自己的学习经验，带着大家一起进入“Win2k下的缓冲区溢出”的神秘地带……

关键词： Windows 缓冲区溢出操作系统应用程序《Windows2000缓冲区溢出入门》

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全球馈送视频网—问题与准则（上）

世界广播电视 2000年第2期14卷 10-14,25页

作者： stor.,SL Video

The Influence of Climate Variability on Holoplanktonic Polychaetes Populations of Ocean Sector of the Colombian Pacific Basin

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Open Journal of Ecology 2021年第4期11卷 317-343页

作者： José Manuel Gutiérrez-Salcedo Adibe Cárdenas-Oliva Néstor H. Campos Marine Fauna of Colombia Biodiversity and Uses Research Group Universidad Nacional de Colombia Caribbean Headquarters Santa Marta Colombia Museo de Historia Natural Marina de Colombia—MHNMC (Makuriwa) Instituto de Investigaciones Marinas y Costeras—INVEMAR Santa Marta Colombia Instituto de Estudios en Ciencias del Mar—CECIMAR. Universidad Nacional de Colombia Caribbean Headquarters Santa Marta Colombia

Studies of holoplanktonic polychaetes in the Tropical Eastern Pacific have focused on their systematics and distribution however, population responses related to climate variability are non-existent. Therefore, the present work described for the first time the influence of the climatic variability 2004-2012 on the holoplanktonic polychaetes populations, as well as their relationship to environmental variables. Species of the Alciopidae, Lopadorrhynchidae and Iospilidae families were identified from 85 samples collected in the Pacific Basin of Colombia, contrasting them with the presence of ENSO, and correlating them with the environmental variables of temperature, salinity and chlorophyll-α concentration. Of the 14 species identified, only Lopadorrhynchus cf. henseni and L. cf. brevis increased their densities under El Niño and correlated positively with temperature. Rhynchonereella cf. petersii correlated negatively with temperature;while R. cf. gracilis and Pelagobia cf. longicirrata were positively correlated with chlorophyll-α concentration and salinity, respectively. Additionally, with the first description of the environmental ranges of the 14 species identified for the Colombian Pacific basin, it was found that the most commons species presented broader environmental ranges. The results from the current research are consistent with previous studies in other regions of the Pacific and latitudes. The responses of the organisms suggest trophic and mobility trends that were not known for tropical holoplanktonic polychaete species.

关键词： Temperature Chlorophyll Oceanic Province Tropical Region El Niño Southern Oscillation—ENOS

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绍兴面料产业革新风起云涌

纺织服装周刊 2009年第18期 34-35页

作者： www张俊龙

绍兴,被誉为"托在一块布上"的经济强县。在其20多年的产业发展中,历经"化纤"革命(1980年前后)、"市场"革命(1988年)、"体制"革命(1993年)、"无梭化"革命(1995年前后)、"外贸"革命(1998年之后),创造了中国式纺织产业集群的发展奇迹,书写... 详细信息

绍兴,被誉为"托在一块布上"的经济强县。在其20多年的产业发展中,历经"化纤"革命(1980年前后)、"市场"革命(1988年)、"体制"革命(1993年)、"无梭化"革命(1995年前后)、"外贸"革命(1998年之后),创造了中国式纺织产业集群的发展奇迹,书写了绍兴纺织不断创新与自我超越的发展历程。在纺织产业发展的新形势下,绍兴在面料产品开发、产业链、创意、企业经营管理等多方面开始了新一轮革新。如今在金融危机的影响下,绍兴更加快了其产业革命的步伐。绍兴的纺织企业家们正在用自己的思考与实践,探寻着中国纺织产业的结构调整与产业升级之路。

关键词：绍兴县产业升级发展历程金融危机不断创新印花面料纺织产业结构调整纺织企业创意

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