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AlGORITHM AND IMPlEMENTATION OF AUTO-SEARCHING WElD lINE FOR WElDING MOBIlE ROBOT

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Chinese Journal of Mechanical Engineering 2006年第2期19卷 176-180页

作者： ZHANG ke lü Xueqin　 WU Yixiong l0U Songnian Institute of Welding Engineering Shanghai Jiaotong UniversityShanghai 200030 China

An algorithm of auto-searching weld line for welding mobile robot is presented. Auto-searching weld line is that the robot can automatically recognize a weld groove according to the characteristics of the weld groove before welding, and then adjust itself posture to the desired status preparing for welding, namely, it is a process that the robot autonomously aligns itself to the center of welding seam. Firstly, the configuration of welding mobile robot with the function of auto-searching weld line is introduced, then the algorithm and implementation of auto-searching weld line are presented on the basis of kinematics model of the robot, at last trajectory planning among auto-searching weld line is investigated in detail. The experiment result shows that the developed welding mobile robot can successfully implement the task of auto-searching weld line before welding, tracking error precision can be controlled to approximate ±1.5 mm, and satisfy the requirement of practical welding project.

关键词： Welding mobile robot Auto-searching weld line Trajectory planning

Hot Dust Acoustic Solitary Waves in Dust Plasma with Variable Dust Charge

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Chinese Physics letters 2001年第8期18卷 1088-1089页

作者： DUAN Wen-Shan lÜ ke-Pu ZHAO Jin-Bao Department of Physics Northwest Normal UniversityLanzhou 730070

Considering the variation of dust charges,We have analytically studied the governing equation for the system with the same model as that for cold dust acoustic waves in a demagnetized plasma but the contribution of hot *** result indicates that the governing equation is also a Korteweg-de Vries equaiton,although its amplitude and width will be smaller compared with the cold dust case.

关键词： equation governing charges

Geochemical Stratigraphy and Microvertebrate Assemblage Sequences across the Silurian/Devonian Transition in South China

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Acta Geologica Sinica(English Edition) 2011年第2期85卷 340-353页

作者： ZHAO Wenjin WANG Nianzhong ZHU Min Ulrich MANN Ulrich HERTEN Andreas lǖke key laboratory of Evolutionary Systematics of Vertebrates Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China Institute of Chemistry and Dynamics of the Geosphere ICG-4 Research Center Juelich GmbH D-52425 Juelich Germany

Carbon isotope （δ13Corg） analyses of non-marine clastic rocks and neritic carbonates and black shales spanning the Silurian/Devonian transition are compared from two richly fossiliferous sequences in Qujing of East Yunnan and Zoige of Sichuan, South China. The two sections, Xishancun and Putonggou sections in South China, reveal positive δ13Corg shifts happening in the Upper Pridoli and lower Devonian and reaching peak values as heavy as -25.2‰ （Xishancun） and -19.9‰（Putonggou） in the lowermost lochkovian following the first occurrence of the thelodont Parathelodus and the conodont Icriodus woschmidti woschmidti （only in Putonggou Section and together with Protathyris-lanceomyonia brachiopod fauna）. These results replicate a globally known positive shift in δ13Corg from the uppermost Silurian to the lowermost Devonian. The δ13Corg variations across the Silurian/Devonian Boundary （SDB） at the two sections in South China exhibit a shift in carbon isotopic composition similar to the detailed SDB curves from the borehole Klonk-1 drilled at top of the Klonk Global Standard Stratotype-Section and Point （GSSP） in the Prague Basin, Czech Republic. In addition, four microvertebrate assemblages, including the liaojiaoshan, Xishancun, Yanglugou and Xiaputonggou assemblages, are recognized from the Silurian/Devonian transition exposed in the Xishancun and Putonggou sections, respectively. The results from both carbon isotope stratigraphy and microvertebrate assemblage sequences suggest that the SDB in South China is located at the base of the Xishancun Formation （between sample QX-20 and sample QX-21） in the Xishancun Section and the lower part of the Xiaputonggou Formation （between sample ZP-09 and sample ZP-10） in the Putonggou Section. The isotopic trend for organic carbon together with the changes of microvertebrate remains across the SDB can offer an approach to a potential correlation of the SDB from different sedimentary facies, which help to correlate the marine with no

关键词： Carbon isotope stratigraphy microvertebrate assemblages Silurian-Devonian Boundary marine and non- marine stratigraphic correlation South China

Progress of Space Medicine Research in China

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空间科学学报 2020年第5期40卷 920-927页

作者： DING Bai lIU Zhaoxia lüke lING Shukuan lIU Yue XU Zi lI Yinghui Astronaut Center of China Beijing 100094

With the approaching of the Chinese Space Station(CSS)era,the focus of space medicine applications and related research has shifted to addressing the astronauts’health support in long-duration spaceflights,including nutrition,countermeasure against the physiological effects of weightlessness,medical monitoring and support,psychology status,etc.,and accordingly the human experiments to simulate long-duration weightlessness have been carried ***,basic research has been put forward in the key areas,such as space bone loss,cardiovascular dysfunction and the molecular mechanisms underlying radiobiological ***,specific novel research fields,such as hypometabolism technology,were *** research projects in the field of space medicine experiment,as an important aspect of the Chinese Space Station’s application,have been officially approved and launched.

关键词： Space medicine Chinese Space Station Health risk

New Modified Jacobi Elliptic Function Expansion Method and Its Application to （3＋1）-Dimensional KP Equation

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Communications in Theoretical Physics 2006年第6期45卷 1063-1068页

作者： DOU Fu-Quan SUN Jian-An DUAN Wen-Shan SHI Yu-Ren lü ke-Pu HONG Xue-Ren College of Physics and Electronics Engineering Northwest Normal University Lanzhou 730070 China

With the aid of computerized symbolic computation, the new modified Jacobi elliptic function expansion method for constructing exact periodic solutions of nonlinear mathematical physics equation is presented by a new general ansatz. The proposed method is more powerful than most of the existing methods. By use of the method, we not only can successfully recover the previously known formal solutions but also can construct new and more general formal solutions for some nonlinear evolution equations. We choose the （3＋1）-dimensional Kadomtsev-Petviashvili equation to illustrate our method. As a result, twenty families of periodic solutions are obtained. Of course, more solitary wave solutions, shock wave solutions or triangular function formal solutions can be obtained at their limit condition.

关键词： MJEFE method KP equation periodic solutions solitary wave solutions

Investigation of Structure and Hydriding Properties of la0.6 Nd0.4 Ni4.s Mn0.2 Cux Alloys

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Journal of Rare Earths 2004年第Z2期22卷 114-117页

作者： Du Ping Cao Wei lü Manqi Yang ke Institute of Metal Research Chinese Academy of SciencesShenyang 110016China Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

The structure and hydriding performance of la0.6Nd0.4Ni4.8Mn0.2Cux (x = 0 ～ 0.4) alloys were investigated in order to develop suitable materials for metal hydride air conditioner. The effect of Cu addition on the crystal structure,equilibrium pressure, hydrogen capacity and hysteresis as well as hydrogen absorption/desorption kinetics were systematically studied by using the measurement of P-C isotherms, X-ray diffraction and scanning electron microscopy. As the amount of Cu increases, the plateau pressure increases and hydrogen absorption/desorption kinetics is improved, but the effective hydrogen storage capacity decreases. It is shown that variations in the basal plane parameter a can be used as an indication for the plateau pressure changes. With the increase of parameter a, the plateau pressure decreases. For la0.6 Nd0.4Ni4.8Mn0.2Cux(x = 0 ～ 0.4) alloys there is a relationship between the effective hydrogen storage capacities and the ratios of their unit cell parameters c and a. The effective hydrogen storage capacity decreases with increase of a/c.

关键词： metal hydride crystal structure hysteresis kinetics unit cell parameters rare earths

基于分布式密钥生成方法的RSA可验证签名分享设计(英文)

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软件学报 2007年第1期18卷 168-176页

作者：吕克伟信息安全国家重点实验室(中国科学院研究生院) 北京100049

主要研究由Franklin和Reiter提出的可验证签名分享(VΣS).它可以允许一个签名的接受者在n个代理之间分享该签名,使得代理者的一些子集以后可以重构该签名.利用安全的分布式密钥生成方式、门限密码系统以及可验证秘密分享,给出了一个RSAV... 详细信息

主要研究由Franklin和Reiter提出的可验证签名分享(VΣS).它可以允许一个签名的接受者在n个代理之间分享该签名,使得代理者的一些子集以后可以重构该签名.利用安全的分布式密钥生成方式、门限密码系统以及可验证秘密分享,给出了一个RSAVΣS的新协议.该协议是有效的、可证安全的,并且可以容忍至多一半代理的恶意行为.

关键词：签名可验证秘密分享协议门限密码系统

Effects of Siraitia grosvenorii extracts on high fat diet-induced obese mice:a comparison with artificial sweetener aspartame

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Food Science and Human Wellness 2022年第4期11卷 865-873页

作者： ke lü Xiaowan Song Peng Zhang Wei Zhao Ning Zhang Fan Yang Wenqiang Guan Jianfu liu He Huang Chi-Tang Ho Rong Di Hui Zhao Tianjin key laboratory of Food and Biotechnology School of Biotechnology and Food ScienceTianjin University of CommerceTianjin 300134China Department of Biochemical Engineering School of Chemical Engineering and TechnologyKey Laboratory of Systems BioengineeringMinistry of EducationTianjin UniversityTianjin 300072China Department of Food Science RutgersThe State University of New JerseyNew BrunswickNJ 08901USA Department of Plant Biology RutgersThe State University of New JerseyNew BrunswickNJ 08901USA

long-term artificial sweetener intake is linked to increased risk of obesity. In the present study, supplement of natural sweetener from Siraitia grosvenorii(SG)(or Momordica grosvenorii) fruit, compared with the artificial sweetener aspartame(ASM), was evaluated for anti-obesity effects on mice fed with high fat diet(HFD). We found that, in contrary to ASM, SG extracts prevented body weight gain, the insulin resistance and fat mass accumulation in HFD mice. SG extracts treatment inhibited the infiltration of inflammatory macrophages and lowered the levels of the fat inflammatory cytokines(leptin, macrophage chemoattractant protein 1(MCP-1) and tumor necrosis factor-α(TNF-α)) in adipose tissues. In addition, SG extracts supplement counteracted the remodeling of gut microbiota resulted from HFD. However, ASM supplement aggravated the HFD-induced obese performances, fat inflammation and dysregulation of gut microbiota. Taken together, our results indicate that supplement of SG extracts may represent a promising alternation of artificial sweeteners in preventing metabolic diseases.

关键词： Siraitia grosvenorii High fat diet Obese Inflammation Gut microbiota

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关于拟本原p-块的一些说明

数学进展 2006年第4期35卷 449-452页

作者：吕克伟信息安全国家重点实验室

本文主要研究了拟本原p-块的性质,从而得到拟本原p-块与群中心结构的一些关系．

关键词：拟本原p-块亏群 p-块支配拟本原特征标