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Dexterity Analysis for Omni-directional Wheeled Mobile Manipulator Based on Double Quaternion

Chinese Journal of Mechanical Engineering 2013年第3期26卷 585-593页

作者： du bin ZHAO Jing SONG Chunyu College of Mechanical Engineering and Applied Electronics Technology Beijing University of Technology

The unified analysis of omni-directional wheeled mobile manipulator(OWMM) through the dimensionally nonhomogeneous Jacobian matrix may lead to unreliable results. The existing researches focus on the integrated performance evaluation of OWMM, without taking the influence of velocity difference into consideration. This paper presents a new approach to formulate the dimensionally homogeneous Jacobian matrix and a new index for OWMM. First, the universal transformational matrix of the link coordinate frame is derived based on double quaternion. The degree of locomotion of a mobile platform and the degrees of manipulation of a manipulator are treated equally as the joints of a redundant composite robot. Then the integrated modeling of OWMM is established, and the non-dimensional Jacobian matrix is obtained from the above matrix. Next, by examining the concept of directional manipulability, a new index is proposed to evaluate the directional manipulability of OWMM along the specified task direction. Furthermore, for the same task and the time of simulation, the kinematic performance of the fixed base operation of the manipulator and the operation of OWMM are analyzed by numerical simulation. The results suggest that the proposed approach is equivalent to the method of traditional kinematic modeling, with the error of numerical solution being 10-7 , and the varying frequency of DMTR is higher than that of the condition number. This indicates that DMTR is more effective to reflect the variation of the task direction. The proposed method can be used to analyze the manipulating capability of OWMM, and has a simple structure and generality in the unified analysis of OWMM.

关键词： double quaternion homogeneous Jacobian mobile manipulator manipulability task direction

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Investigation of Hydrolysis in Poly(ethylene terephthalate) by FTIR-ATR

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Chinese Journal of Polymer Science 2014年第2期32卷 230-235页

作者： bin du 杨睿 Xu-ming Xie Advance Materials Laboratory Department of Chemical Engineering Tsinghua University

The hydrothermal aging of poly（ethylene terephthalate）（PET） was investigated at 70-95 ℃. A new method to investigate the hydrolysis degree of PET by Fourier transform infrared spectroscopy （FTIR） was proposed. The spectra during the hydrothermal aging were measured using attenuated total reflection accessory （ATR）. Peak resolving of carbonyl regions was performed, and the ratio of two groups of bands representing carboxylic acids and esters respectively were calculated to show the hydrolysis degree of ester groups in PET. The acid/ester ratio shows exactly the same trend as the average chain scission number per unit mass at various temperatures and thus can be used as a parameter to characterize the hydrolysis and random chain scission of PET. This method related to the hydrolysis mechanism directly, is simple, fast and convenient compared to the traditional methods such as viscometry, end-group titration and size exclusion chromatography （SEC）. It may also be useful in hydrolysis characterization of other polyesters.

关键词： Poly(ethylene terephthalate) FTIR-ATR Hydrolysis Acid/ester ratio.

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Hybrid optimization for charge planning problem in twin strands continuous casting production

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Journal of Iron and Steel Research International 2021年第5期28卷 520-529页

作者： Jian Yi Shu-jin Jia bin du College of Information Science and Engineering Northeastern UniversityShenyang 110819LiaoningChina Institute of Intelligent Manufacturing Baosteel Central Research InstituteShanghai 201900China

Charge planning is one of batching problems for steelmaking and continuous casting production,and its optimization will be conducive to subsequent cast *** planning problem in the twin strands continuous casting production was studied,where casting width of the odd strand might be different from that of the even *** the different widths in the twin strands,the resulting counterweights and the constraints of steelmaking and continuous casting,a multiobjective optimization model was established to minimize the number of charges,the number of scale pairs,the surplus and the upgrading costs of steel ***,a hybrid optimization algorithm combined with heuristic and mutation-based estimation of distribution algorithm was proposed to solve the *** were conducted on several groups of test data collected from practical production orders of *** computational results demonstrate that the proposed algorithm can generate better solutions than the manual *** proposed model and algorithm proved to be effective and practical.

关键词： Steelmaking Continuous casting Production planning Charge Cast Estimation of distribution algorithm

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Phenomena and Images Research on the Taoist Ecological Ethics Value

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学术界 2014年第8期 249-253页

作者： du bin Students Affairs Office Sichuan Agricultural University Ya' an Sichuan 625014

Dispute upon the Taoist natural philosophical ethic value and the spreading and application of the ecological ethic customs in the academic circle blocks related research upon the ecological ethics of Taoist natural *** regard to the two research focuses of the ecological ethics at present—the continuous development of the modern ecological protection and the wild value strategy of ecological maintenance,it is useful to excavate the development from ecological phenomenological cognition to ecological image system so as to provide a new perspective for research upon the Taoist philosophy;at the same time,having a better understanding of the significance of treating ecology as the ethnography is good for integrating the Taoist natural philosophy into ecological theories and developing the national ethical value.

关键词：生态伦理伦理价值道教影像自然哲学道家哲学调制解调器生态学意义

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Agile Satellite Mission Planning via Task Clustering and Double-Layer Tabu Algorithm

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Computer Modeling in Engineering & Sciences 2020年第1期122卷 235-257页

作者： Yanbin Zhao bin du Shuang Li Shanghai Institute of Satellite Engineering Shanghai201109China Nanjing University of Aeronautics and Astronautics Nanjing210016China

Satellite observation schedule is investigated in this paper.A mission planning algorithm of task clustering is proposed to improve the observation efficiency of agile *** newly developed method can make the satellite observe more targets and therefore save observation ***,for the densely distributed target points,a preprocessing scheme based on task clustering is *** target points are clustered according to the distance ***,the local observation path is generated by Tabu algorithm in the inner layer of cluster ***,considering the scatter and cluster sets,the global observation path is obtained by adopting Tabu algorithm in the outer *** results show that the algorithm can effectively reduce the task planning time of large-scale point targets while ensuring the optimal solution quality.

关键词： Mission planning agile satellite task clustering Tabu algorithm

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Influence of Rashba spin–orbit coupling on Josephson effect in triplet superconductor/two-dimensional semiconductor/triplet superconductor junctions

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Chinese Physics B 2022年第7期31卷 490-497页

作者： bin-Hao du Man-Ni Chen Liang-bin Hu Guangdong Provincial Key Laboratory of Quantum Engineering and Quantum Materials School of Physics and Telecommunication EngineeringSouth China Normal UniversityGuangzhou 510631China

We study theoretically Josephson effect in a planar ballistic junction between two triplet superconductors with pwave orbital symmetries and separated by a two-dimensional(2D)semiconductor channel with strong Rashba spin–orbit *** triplet superconductors,three types of orbital symmetries are *** use Bogoliubov–de Gennes formalism to describe quasiparticle propagations through the junction and the supercurrents are calculated in terms of Andreev reflection *** features of the variation of the supercurrents with the change of the strength of Rashba spin–orbit coupling are investigated in some *** is found that for the three types of orbital symmetries considered,both the magnitudes of supercurrent and the current-phase relations can be manipulated effectively by tuning the strength of Rashba spin–orbit *** interplay of Rashba spin–orbit coupling and Zeeman magnetic field on supercurrent is also investigated in some detail.

关键词： Josephson effect Rashba spin–orbit coupling triplet superconductor 0-πtransitions

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Multi-objective model and optimization algorithm based on column generation for continuous casting production planning

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Journal of Iron and Steel Research International 2019年第3期26卷 242-250页

作者： Jian Yi Shu-jin Jia bin du Qing Liu Institute of Intelligent Manufacturing Baosteel Central Research Institute Shanghai 201900 China College of Information Science and Engineering Northeastern UniversityShenyang 110819 LiaoningChina State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China

The optimization of continuous casting production planning(CCPP)in the steel industry was *** essence of CCPP is the productive capability balance of back-end facilities over the planning time *** facilities with the demands of productive capability are called the *** the basis of charge plans,the task of CCPP is to produce cast plans according to the rules of cast design in order to meet the ***,a multi-objective model was established with considering the demands of flows,the capability requirements of liquid steel refini ng devices,and the rules of cast ***,the model was decomposed into a master problem(set partitioning problem model)and a series of subproblem(pricing problem model)by using Dantzig-Wolfe decomposition ***,a column generation-based optimization algorithm(CGBOA)was *** experimental results on practical production data from Baosteel demonstrate that the proposed algorithm is effective and ***,a new decision support system based on CGBOA has been successfully established and applied to No.2 Steelmaking Plant at Baosteel.

关键词： Steelmaking Continuous casting Production planning Charge Cast Column generation

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Blood gas analysis as a surrogate for microhemodynamic monitoring in sepsis

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World Journal of Emergency Medicine 2023年第6期14卷 421-427页

作者： Jingyi Wang Li Weng Jun Xu bin du Emergency Department State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China Medical Intensive Care Unit State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100730China

BACKGROUND:Emergency patients with sepsis or septic shock are at high risk of *** increasing attention to microhemodynamics,the clinical use of advanced microcirculatory assessment is limited due to its *** blood gas analysis is a widely used technique reflecting global oxygen supply and consumption,it may serve as a surrogate for microcirculation monitoring in septic ***:We performed a search using PubMed,Web of Science,and Google *** studies and reviews that were most relevant to septic microcirculatory dysfunctions and blood gas parameters were identified and ***:Based on the pathophysiology of oxygen metabolism,the included articles provided a general overview of employing blood gas analysis and its derived set of indicators for microhemodynamic monitoring in septic *** flaws,several parameters are linked to changes in the microcirculation.A comprehensive interpretation of blood gas parameters can be used in order to achieve hemodynamic optimization in septic ***:Blood gas analysis in combination with clinical performance is a reliable alternative for microcirculatory assessments.A deep understanding of oxygen metabolism in septic settings may help emergency physicians to better use blood gas analysis in the evaluation and treatment of sepsis and septic shock.

关键词： Sepsis Microcirculation Blood gas analysis Emergency service

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Seismic stability analysis of concrete gravity dams with penetrated cracks

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Water Science and Engineering 2012年第1期5卷 105-119页

作者： Shou-yan JIANG Cheng-bin du College of Mechanics and Materials Hohai UniversityNanjing 210098PR.China

The seismic stability of a cracked dam was examined in this study. Geometric nonlinearity and large deformations, as well as the contact condition at the crack site, were taken into consideration. The location of penetrated cracks was first identified using the concrete plastic-damage model based on the nonlinear finite element method （FEM）. Then, the hard contact algorithm was used to simulate the crack interaction in the normal direction, and the Coloumb friction model was used to simulate the crack interaction in the tangential direction. After verification of numerical models through a case study, the seismic stability of the Koyna Dam with two types of penetrated cracks is discussed in detail with different seismic peak accelerations, and the collapse processes of the cracked dam are also presented. The results show that the stability of the dam with two types of penetrated cracks can be ensured in an earthquake with a magnitude of the original Koyna earthquake, and the cracked dam has a large earthquake-resistant margin. The failure processes of the cracked dam in strong earthquakes can be divided into two stages： the sliding stage and the overturning stage. The sliding stage ends near the peak acceleration, and the top block slides a long distance along the crack before the collapse occurs. The maximum sliding displacement of the top block will decrease with an increasing friction coefficient at the crack site.

关键词： seismic stability concrete gravity dam penetrated crack plastic-damage model hard contact algorithm Coloumb friction model joint opening

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Application of strength reduction method to dynamic anti-sliding stability analysis of high gravity dam with complex dam foundation

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Water Science and Engineering 2011年第2期4卷 212-224页

作者： Deng-hong CHEN Cheng-bin du Department of Engineering Mechanics College of Mechanics and Materials Hohai University Nanjing 210098 P. R. China

Considering that there are some limitations in analyzing the anti-sliding seismic stability of dam-foundation systems with the traditional pseudo-static method and response spectrum method, the dynamic strength reduction method was used to study the deep anti-sliding stability of a high gravity dam with a complex dam foundation in response to strong earthquake-induced ground action. Based on static anti-sliding stability analysis of the dam foundation undertaken by decreasing the shear strength parameters of the rock mass in equal proportion, the seismic time history analysis was carried out. The proposed instability criterion for the dynamic strength reduction method was that the peak values of dynamic displacements and plastic strain energy change suddenly with the increase of the strength reduction factor. The elasto-plastic behavior of the dam foundation was idealized using the Drucker-Prager yield criterion based on the associated flow rule assumption. The result of elasto-plastic time history analysis of an overflow dam monolith based on the dynamic strength reduction method was compared with that of the dynamic linear elastic analysis, and the reliability of elasto-plastic time history analysis was confirmed. The results also show that the safety factors of the dam-foundation system in the static and dynamic cases are 3.25 and 3.0, respectively, and that the F2 fault has a significant influence on the anti-sliding stability of the high gravity dam. It is also concluded that the proposed instability criterion for the dynamic strength reduction method is feasible.

关键词： dynamic anti-sliding stability complex dam foundation dynamic strength reduction method instability criteria elasto-plastie model dynamic time history analysis gravity dam

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