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Investigation on the choice of boundary conditions and shape functions for flexible multi-body system

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Acta Mechanica Sinica 2012年第1期28卷 180-189页

作者： ke-Qi pan Jin-Yang Liu School of Naval Architecture Ocean and Civil EngineeringShanghai Jiaotong University200240 ShanghaiChina

The objective of this investigation is to examine the correctness and efficiency of the choice of boundary conditions when using assumed mode approach to simulate flexible multi-body systems. The displacement field due to deformation is approximated by the Rayleigh-Ritz assumed modes in floating frame of reference （FFR） formulation. The deformations obtained by the absolute nodal coordinate （ANC） formulation which are transformed by two sets of reference coordinates are introduced as a criterion to verify the accuracy of the simulation results by using the FFR formulation. The relationship between the deformations obtained from different boundary conditions is revealed. Nu- merical simulation examples demonstrate that the assumed modes with cantilevered-free, simply-supported and free- free boundary conditions without inclusion of rigid body modes are suitable for simulation of flexible multi-body system with large over all motion, and the same physical deformation can be obtained using those mode functions, differ only by a coordinate transformation. It is also shown that when using mode shapes with statically indeterminate boundary conditions, significant error may occur. Furthermore, the slider crank mechanism with rigid crank is accurate enough for investigating boundary condition problem of flexible multi-body system, which cost significant less simulating time.

关键词： Multi-body systems. Boundary conditions - Assumed mode approach

Sorption kinetics of parent and substituted PAHs for low-density polyethylene（LDPE）:Determining their partition coefficients between LDPE and water(KLDPE) for passive sampling

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Journal of Environmental Sciences 2020年第1期32卷 349-360页

作者： Pei Lei Jinjie Zhu ke pan Hong Zhang State key Laboratory of Pollution Control and Resources Reuse School of the EnvironmentNanjing UniversityNanjing 210023China State key Laboratory cf Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Institute for Advanced Study Shenzhen UniversityShenzhen 518060China University of Chinese Academy of Sciences Beijing 100049China

Low-density polyethylene(LDPE)has been widely used as a sorbent for passive sampling of hydrophobic organic contaminants(HOCs)in aquatic ***,it has seen only limited application in passive sampling for measurement of freely dissolved concentrations of parent and substituted PAHs(SPAHs),which are known to be toxic,mutagenic and ***,the 16 priority PAHs and some typical PAHs were selected as target compounds and were simultaneously determined by gas chromatography–mass spectrometer(GC–MS).Some batch experiments were conducted in the laboratory to explore the adsorption kinetics of the target compounds in LDPE *** results showed that both PAHs and SPAHs could reach equilibrium status within19–38 days in sorption kinetic *** coefficients of partitioning between LDPE film(50μm thickness)and water(KLDPE)for the 16 priority PAHs were in good agreement with previously reported values,and the values of KLDPEfor the 9 SPAHs are reported in this study for the first *** linear relationships were observed,i.e.,log KLDPE=0.705×log KOW+1.534 for PAHs(R^2=0.8361,p<0.001)and log KLDPE=0.458×log KOW+3.092 for SPAHs(R^2=0.5609,p=0.0077).The selected LDPE film was also proven to meet the condition of"zero sink"for the selected target *** results could provide basic support for the configuration and in situ application of passive samplers.

关键词： Low-density polyethylene(LDPE) PAHs Substituted PAHs(SPAHs) Freely dissolved concentrations Passive sampling

Quantitative relationship between flagellate abundance and suspended particle density in Huanghai Sea and East China Sea in summer

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Acta Oceanologica Sinica 2006年第2期25卷 109-118页

作者： HUANG Lingfeng pan ke GUO Feng Department of Oceanography ＆ Institute of Subtropical Oceanography Xiamen University Xiamen 361005 China State key Laboratory of Marine Environmental Science Xiamen University Xiamen 361005 China

An investigation was carried out in the Huanghai Sea and the East China Sea to study the quantitative relationship between the abundance of flagellates and the density of suspended particles in the summer of 2001. The results show that the abundance of flagellates varies from 44-12 600 cell/cm^3, and flagellates sometimes constitutes a significant part of suspended particles. The size-spectra of suspended particles can be divided into four categories： flat spectrum, humped spectrum, plankton spectrum and mixed spectrum. In general, the abundance of flagellates varies in proportion to the density of suspended particles. However, their quantitative relations reveal different characteristics in the seawater samples of different types of particle-size spectrum. This is only a preliminary study of the quantitative relationship between flagellates and suspended particles, which might lead to a potential convenient approach to the estimation of flagellate abundance in the sea.

关键词： marine flagellates suspended particles particle-size spectra quantitative relationship

An effective invasive weed optimization algorithm for the flow shop scheduling with intermediate buffers

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An effective invasive weed optimization algorithm for the fl...

Multi-Objective Teaching-Learning-Based Optimizer for a Multi-Weeding Robot Task Assignment Problem

第25届中国控制与决策会议

作者： Hong-yan Sang Quan-ke pan School of Mathematics Science Liaocheng University State key Laboratory of Synthetical Automation for Process Industries Northeastern University College of Computer Science Liaocheng University

ISBN: (纸本)9781467355322

The flow shop scheduling problem with intermediate bffers has important applications in modern industry. This paper addresses this problem with the objective of minimizing the makespan and presents an effective discrete IWO （DIWO） algorithm. In the proposed DIWO, a Nawaz-Enscore-Ham heuristic is used to generate an initial solution with a certain level of quality. An improved IWO-search mechanism is utilized to evolve in the global space. An efficient local search algorithm is embedded in the algorithm to enhance exploitation. Computational experiments demonstrate the effectiveness of the proposed DIWO algorithm for solving the problem.

关键词： Flow shop with intermediate buffers Makespan Discrete invasive weed optimization Local search

来源： cnki会议评论

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Tsinghua Science and Technology 2024年第5期29卷 1249-1265页

作者： Nianbo Kang Zhonghua Miao Quan-ke pan Weimin Li M.Fatih Tasgetiren School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444China School of Computer Engineering and Science Shanghai UniversityShanghai 200444China Industrial Engineering Department Baskent UniversityAnkara 06790Türkiye

With the emergence of the artificial intelligence era,all kinds of robots are traditionally used in agricultural ***,studies concerning the robot task assignment problem in the agriculture field,which is closely related to the cost and efficiency of a smart farm,are ***,a Multi-Weeding Robot Task Assignment(MWRTA)problem is addressed in this paper to minimize the maximum completion time and residual herbicide.A mathematical model is set up,and a Multi-Objective Teaching-Learning-Based Optimization(MOTLBO)algorithm is presented to solve the *** the MOTLBO algorithm,a heuristicbased initialization comprising an improved Nawaz Enscore,and Ham(NEH)heuristic and maximum loadbased heuristic is used to generate an initial population with a high level of quality and *** effective teaching-learning-based optimization process is designed with a dynamic grouping mechanism and a redefined individual updating rule.A multi-neighborhood-based local search strategy is provided to balance the exploitation and exploration of the ***,a comprehensive experiment is conducted to compare the proposed algorithm with several state-of-the-art algorithms in the *** results demonstrate the significant superiority of the proposed algorithm for solving the problem under consideration.

关键词： genetic algorithm heuristic algorithm Multi-Weeding Robot Task Assignment(MWRTA) teaching optimization algorithm

A new Lycopodium alkaloid from Phlegmariurus fargesii

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Chinese Journal of Natural Medicines 2014年第5期12卷 373-376页

作者： pan ke LUO Jian-Guang KONG Ling-Yi State key Laboratory of Natural Medicines Department of Natural Medicinal Chemistry China Pharmaceutical University

AIM: To investigate the chemical constituents from the whole plants of Phlegmariurus fargesii. METHOD: Compounds were isolated by repeated silica gel column chromatography. Their structures were elucidated by spectroscopic methods and chemical correlation. The acetylcholinesterase(AChE) inhibitory activity of the isolated compounds was evaluated. RESULTS: A new Lycopodium alkaloid, lycopodine N-oxide(1), along with lycopodine(2), 8,15-dehydrolycopodine(3), 6α-hydroxylycopodine(4), deacetyllycoclavine(5), N-methylhuperzine B(6), lycodine(7), and phlegmarine(8), was isolated. CONCLUSION: Compound 1 is a new Lycopodium alkaloid, and compound 3 was obtained from nature for the first time. Other alkaloids are isolated from this plant for the first time.

关键词： Phlegmariurusfargesii Lycopodium alkaloids Lycopodine N-oxide

An ocean acidification-simulated system and its application in coral physiological studies

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Acta Oceanologica Sinica 2018年第12期37卷 55-62页

作者： ZHENG Xinqing WANG Chenying HADI Tri Aryono YE Youyin pan ke Third Institute of Oceanography Ministry of Natural Resources Research Center for Oceanography Indonesian Institute of Sciences Institute for Advanced Study Shenzhen University

Due to the elevated atmospheric carbon dioxide, ocean acidification(OA) has recently emerged as a research theme in marine biology due to an expected deleterious effect of altered seawater chemistry on calcification. A system simulating future OA scenario is crucial for OA-related studies. Here, we designed an OA-simulated system(OASys) with three solenoid-controlled CO_2 gas channels. The OASys can adjust the pH of the seawater by bubbling CO_2 gas into seawaters via feedback systems. The OASys is very simple in structure with an integrated design and is new-user friendly with the instruction. Moreover, the OASys can monitor and record real-time pH values and can maintain pH levels within 0.02 pH unit. In a 15-d experiment, the OASys was applied to simulate OA in which the expected target pH values were 8.00, 7.80 and 7.60 to study the calcifying response of Galaxea fascicularis. The results showed daily mean seawater pH values held at pH 8.00±0.01, 7.80±0.01 and 7.61±0.01 over15 d. Correspondingly, the coral calcification of G. fascicularis gradually decreased with reduced pH.

关键词： ocean acidification OASys coral Galaxea fascicularis

Probing the processing of facial expressions in monkeys via time perception and eye tracking

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Zoological Research 2023年第5期44卷 882-893页

作者： Xin-He Liu Lu Gan Zhi-Ting Zhang pan-ke Yu Ji Dai Shenzhen Technological Research Center for Primate Translational Medicine Shenzhen-Hong Kong Institute of Brain ScienceShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China CAS key Laboratory of Brain Connectome and Manipulation Brain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China Guangdong Provincial key Laboratory of Brain Connectome and Behavior Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China Research Center for Medical Artificial Intelligence Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China University of Chinese Academy of Sciences Beijing 100049China

Accurately recognizing facial expressions is essential for effective social ***-human primates(NHPs)are widely used in the study of the neural mechanisms underpinning facial expression processing,yet it remains unclear how well monkeys can recognize the facial expressions of other species such as *** this study,we systematically investigated how monkeys process the facial expressions of conspecifics and humans using eye-tracking technology and sophisticated behavioral tasks,namely the temporal discrimination task(TDT)and face scan task(FST).We found that monkeys showed prolonged subjective time perception in response to Negative facial expressions in monkeys while showing longer reaction time to Negative facial expressions in *** faces also reliably induced divergent pupil contraction in response to different expressions,while human faces and scrambled monkey faces did ***,viewing patterns in the FST indicated that monkeys only showed bias toward emotional expressions upon observing monkey ***,masking the eye region marginally decreased the viewing duration for monkey faces but not for human *** probing facial expression processing in monkeys,our study demonstrates that monkeys are more sensitive to the facial expressions of conspecifics than those of humans,thus shedding new light on inter-species communication through facial expressions between NHPs and humans.

关键词： Monkey Facial expression Time perception Eye-tracking Pupil size

Three-dimensional echocardiographic assessment of left ventricular volume in different heart diseases using a fully automated quantification software

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World Journal of Clinical Cases 2022年第13期10卷 4050-4063页

作者： Chen-ke pan Bo-Wen Zhao Xuan-Xuan Zhang Mei pan Yan-Kai Mao Yuan Yang Department of Diagnostic Ultrasound and Echocardiography Sir Run Run Shaw HospitalZhejiang University College of MedicineHangzhou 310016Zhejiang ProvinceChina Department of Ultrasound The Fourth Affiliated Hospital of Zhejiang University College of MedicineYiwu 322200Zhejiang ProvinceChina

BACKGROUND HeartModel(HM)is a fully automated adaptive quantification software that can quickly quantify left heart volume and left ventricular *** study used HM to quantify the left ventricular end-diastolic(LVEDV)and end-systolic volumes(LVESV)of patients with dilated cardiomyopathy(DCM),coronary artery heart disease with segmental wall motion abnormality,and hypertrophic cardiomyopathy(HCM)to determine whether there were differences in the feasibility,accuracy,and repeatability of measuring the LVEDV,LVESV,LV ejection fraction(LVEF)and left atrial end-systolic volume(LAESV)and to compare these measurements with those obtained with traditional twodimensional(2D)and three-dimensional(3D)*** To evaluate the application value of HM in quantifying left heart chamber volume and LVEF in clinical *** A total of 150 subjects who underwent 2D and 3D echocardiography were divided into 4 groups:(1)42 patients with normal heart shape and function(control group,Group A);(2)35 patients with DCM(Group B);(3)41 patients with LV remodeling after acute myocardial infarction(Group C);and(4)32 patients with HCM(Group D).The LVEDV,LVESV,LVEF and LAESV obtained by HM with(HM-RE)and without regional endocardial border editing(HM-NE)were compared with those measured by traditional 2D/3D echocardiographic methods to assess the correlation,consistency,and repeatability of all ***(1)The parameters measured by HM were significantly different among the groups(P<0.05 for all).Compared with Groups A,C,and D,Group B had higher LVEDV and LVESV(P<0.05 for all)and lower LVEF(P<0.05 for all);(2)HM-NE overestimated LVEDV,LVESV,and LAESV with wide biases and underestimated LVEF with a small bias;contour adjustment reduced the biases and limits of agreement(bias:LVEDV,28.17 mL,LVESV,14.92 mL,LAESV,8.18 mL,LVEF,-0.04%).The correlations between HM-RE and advanced cardiac 3D quantification(3DQA)(r_(s)=0.91-0.95,P<0.05 for all)were higher than those between HM-NE(

关键词： HeartModel Three-dimensional echocardiography Left ventricular volume Left ventricular ejection function Left atrial volume