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Hand-eye calibration with a new linear decomposition algorithm

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第10期9卷 1363-1368页

作者： Rong-hua liang jian-fei MAO College of Information Engineering Zhejiang University of Technology Hangzhou 310032 China

To solve the homogeneous transformation equation of the form AX=XB in hand-eye calibration, where X represents an unknown transformation from the camera to the robot hand, and A and B denote the known movement transformations associated with the robot hand and the camera, respectively, this paper introduces a new linear decomposition algorithm which consists of singular value decomposition followed by the estimation of the optimal rotation matrix and the least squares equation to solve the rotation matrix of X. Without the requirements of traditional methods that A and B be rigid transformations with the same rotation angle, it enables the extension to non-rigid transformations for A and B. The details of our method are given, together with a short discussion of experimental results, showing that more precision and robustness can be achieved.

关键词： Homogeneous transformation equation Singular value decomposition (SVD) Optimal rotation matrix Rigid transformations

Relaxation of Evolutionary Dynamics on the Bethe Lattice

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Chinese Physics Letters 2012年第3期29卷 259-262页

作者： TIAN liang LIN min College of Science Nanjing University of Aeronautics and AstronauticsNanjing 210016 School of Economics and Management Tsinghua UniversityBeijing 100084

Realistic evolutionary systems are generally structured and are in infinite *** study the relaxation behavior of evolutionary dynamics on a Bethe lattice,which concerns the invasion of mutants into a population of wild-type *** the boundary effect plays a significant role in a finite system,with proper approximation we propose an effective method to characterize the evolutionary *** relaxation behavior of the invasion process is analytically investigated,which is confirmed by extensive *** work is the first systematical investigation on evolutionary dynamics in an infinitely dimensional lattice.

关键词： dynamics Bethe relaxation

Processing of a low-costγ-γ'NiPtAl coating with improved oxidation resistance

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Rare Metals 2024年第6期43卷 2832-2841页

作者： Yan jiang liang-liang Wei jian He Hong-Bo Guo School of Materials Science and Engineering Beihang UniversityBeijing 100191China Key Laboratory of High-Temperature Structural Materials and Protective Coatings Ministry of Industry and Information TechnologyBeihang UniversityBeijing 100191China

A novelγ-γ'(Ni solid solution—Ni_(3)Al)NiPtAl coating was produced on advanced single-crystal(SC)superalloy N5 by electroplating of a thin Pt coating with~3μm in thickness followed by heat treatment at 1000℃in *** comparison,a traditionalγ-γ'NiPtAl coating was also produced by electroplating of a thick Pt coating with~6μm in thickness followed by heat treatment at 1100℃in *** novel coating has a mass gain of~0.5 mg·cm^(-2)after 100 h 1-h cyclic oxidation at 1150℃,showing better oxidation resistance than the traditional *** oxide scale mostly consisting ofα-Al_(2)O_(3)grew on the novel coating because the element Cr from the SC alloy substrate contributes to the formation ofα-Al_(2)O_(3).Pt content in the novel coating has significant effect on the oxidation *** optimized Pt content in the coating is about 16 at%,which is helpful to reduce the diffusion of harmful elements from the substrate into the coating but also to reduce the cost of the coating.

关键词： γ-γ'NiPtAl coating Platinum Oxidation Al_(2)O_(3) Superalloy

Mobilities and leachabilities of heavy metals in sludge with humus soil

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Journal of Environmental Sciences 2011年第2期23卷 247-254页

作者： Rui Zhu min Wu jian Yang State Key Laboratory of Pollution Control and Resources Reuse Tongji University Shanghai 200092 China.

Chemical forms of Zn, Ni, Cu, and Pb in municipal sewage sludge were investigated by adding humus soil to sludge and by performing sequential extraction procedures. In the final sludge mixtures, Zn and Ni were mainly found in Fe/Mn oxide-bound （F3） and organic matter/sulfide-bound （F4） forms. For Zn, exchangeable （F1）, carbonate-bound （F2）, and F3 forms were transformed to F4 and residual forms （F5）. For Ni, F1 and F2 forms were transformed to F1, F2, and F3 forms. Both Cu and Pb were strongly associated with the stable forms F4 and F5. For Cu, F2 and F3 forms were major contributors, while for Pb, F3 and F4 forms were major contributors to F5. Humus soil dosage and pH conditions in the sludge were strongly correlated with the forms of heavy metals. Five forms were used to evaluate metal mobilities in the initial and final sludge mixtures. The mobilities of the four heavy metals studied decreased after 28 days. The metal mobilities in the final sludge mixtures were ranked in the following order： Ni 〉 Zn 〉 Cu = Pb. Leaching tests showed that the mobilities of Zn and Ni in lower pH conditions （pH 4） were higher than those in higher pH conditions （pH 8）.

关键词： sludge heavy metal humus soil mobility leachability

Robust Stability and Stabilization of Discrete Singular Systems with Interval Time-varying Delay and Linear Fractional Uncertainty

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International Journal of Automation and computing 2012年第1期9卷 8-15页

作者： jian-min Jiao Department of Mathematics Baoji University of Arts and Sciences Baoji 721013 PRC

The robust stability and robust stabilization problems for discrete singular systems with interval time-varying delay and linear fractional uncertainty are discussed. A new delay-dependent criterion is established for the nominal discrete singular delay systems to be regular, causal and stable by employing the linear matrix inequality （LMI） approach. It is shown that the newly proposed criterion can provide less conservative results than some existing ones. Then, with this criterion, the problems of robust stability and robust stabilization for uncertain discrete singular delay systems are solved, and the delay-dependent LMI conditions are obtained. Finally, numerical examples are given to illustrate the effectiveness of the proposed approach.

关键词： Discrete singular systems time-varying delay linear fractional uncertainty robust stability robust stabilization linear matrix inequality (LMI).

Soundscape of the West Lake Scenic Area with profound cultural background—a case study of Evening Bell Ringing in Jingci Temple,China

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第3期14卷 219-229页

作者： jian GE min GUO Miao YUE Deptartment of Architecture Zhejiang University State Key Lab of Subtropical Building Science South China University of Technology Deptartment of Architecture and Art Zhejiang College of Construction

From the case study of Evening Bell Ringing at Nanping Hill,one of the West Lake Cultural Landscapes in Hangzhou,China,we investigated the soundscape of a scenic area with a profound cultural ***,we conducted the soundscape physical index of the area in both winter and spring seasons to analyze its objective graphical ***,we focused on people's reactions to the soundscape in order to obtain a subjective evaluation of each component in the soundscape and integrated ***,the relationship between the objective data and the subjective evaluation was ***,the impacts of the natural environment,history,and cultural factors on the evaluation of the Jingci Temple soundscape were *** was found that natural sounds,cultural sounds,and historic sounds were widely acclaimed in people's subjective feelings,which indicated the close relationships among historical and cultural background,soundscape,and natural ***,the conclusion was made that soundscape should be consistent with the local natural environment and the historical and cultural background.

关键词： Soundscape Culture Evaluation West Lake Evening Bell Ringing at Nanping Hill

Evaluation of CMIP6 HighResMIP models in simulating precipitation over Central Asia

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Advances in Climate Change Research 2022年第1期13卷 1-13页

作者： liang-liang LI jian LI Ru-Cong YU College of Atmospheric Sciences Lanzhou UniversityLcmzhou 730000China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Research Center for Disastrous Weather Over Hengduan Mountains&Low-Latitude Plateau China Meteorological AdministrationKunming 650034China

The High Resolutio n Model Intercomparison Project(HighResMIP)experiment within the Coupled Model In tercomparison Project Phase 6(CMIP6),for the first time,has provided an opportunity to evaluate the performance of climate models over complex *** on the HighResMIP's historical simulations of atmospheric general circulation models,the performances of global high-resolution models,with a horizontal resolution finer than 50 km,in representing precipitation over Central Asia were evaluated using rain gauge observation *** the models successfully reproduce the large precipitation regions that are located over the mountainous areas and Northern Central ***,nearly all the models overestimate precipitation frequency over Central Asia and large overestimations of precipitation amount and frequency are located over the mountainous *** the HighResMIP multi-model ensemble mean performs better than all individual models at simulating the spatial pattern of precipitation frequency,it is inferior to HadGEM3-GC31-HM and ECMWF-IFS-HR at simulating that of precipitation *** simulation performance exhibits remarkable regional *** the Qilian Mountains,the relationship between precipitation and elevation is totally captured by climate *** contrast,over the Tianshan Mountains,the models fail to simulate the decrease in precipitation frequency after elevation higher than the maximum precipitation *** models successfully reproduce the annual cycle shape of precipitation amount over the Southern Central Asia,Qilian Mountains and Tianshan Mountains,but fail to reproduce it over the Northern Central *** than half of the high-resolution GCMs have a reduced bias relative to the corresponding low-resolution *** performances of most high-resolution GCMs in simulating precipitation pattern are well over the Tianshan Mountains.

关键词： CMIP6 HighResMIP Model evaluation Precipitation Elevation Central Asia

TAR~*:an improved process similarity measure based on unfolding of Petri nets

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计算机集成制造系统 2012年第8期18卷 1774-1784页

作者： WANG Wen-xing WANG jian-min School of Software Tsinghua University Beijing 100084 China ministry of Education Key Laboratory for Information System Security Tsinghua UniversityBeijing 100084 China Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China

Determining the similarity degree between process models was very important for their management,reuse,and *** approaches either focused on process model's structural aspect,or had inefficiency or imprecision in behavioral *** at these problems,a novel similarity measure which extended an existing method named Transition Adjacent Relation(TAR) with improved precision and efficiency named TAR * was *** ability of measuring similarity was extended by eliminating the duplicate tasks without impacting the *** precision,TARs was classified into repeatable and unrepeatable ones to identify whether a TAR was involved in a *** new kinds of TARs were added,one related to the invisible tasks after the source place and before sink place,and the other representing implicit *** efficiency,all TARs based on unfolding instead of its reach ability graph of a labeled Petri net were calculated to avoid state space *** on artificial and real-world process models showed the effectiveness and efficiency of the proposed method.

关键词： transition adjacent relation unfolding Petri nets behavioral similarity

Ligand-controlled NiH-catalyzed regiodivergent hydroalkylation of 2-alkenylazaarenes

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Science China Chemistry 2024年第6期67卷 1935-1940页

作者： Ya-Ping Shao Zhuo-min Chi Yong-min liang State Key Laboratory of Applied Organic Chemistry School of Chemistry and Chemical EngineeringLanzhou UniversityLanzhou730000China

A nickel-hydride(Ni H)-catalyzed migratory and nonmigratory hydroalkylation reaction of 2-alkenyl azaarenes with alkyl iodines has been established through strategic modulation of N-or P-donor *** method enables the synthesis of diverseβ-orγ-branched aromatic *** mild regiodivergent protocols exhibit wide substrate scope,excellent functional tolerance,and great reaction yield with remarkable ***,deuterium labeling studies reveal Ni H-catalyzed interrupted chain-walking mode as the mechanism behind remotedβ-selective hydroalkylation reaction—an interesting phenomenon mediated through aromatic imine directing groups.

关键词： NiH regiodivergent hydroalkylation azaarenes interrupted chain-walking