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A Multi-stage Heuristic Algorithm for Matching Problem in the Modified Miniload Automated Storage and Retrieval System of E-commerce

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Chinese Journal of Mechanical Engineering 2016年第3期29卷 641-648页

作者： WANG Wenrui wu Yaohua wu yingying School of Transportation Engineering Shandong Jianzhu University School of Control Science and Engineering Shandong University

E-commerce, as an emerging marketing mode, has attracted more and more attention and gradually changed the way of our life. However, the existing layout of distribution centers can＇t fulfill the storage and picking demands of e-commerce sufficiently. In this paper, a modified miniload automated storage/retrieval system is designed to fit these new characteristics of e-commerce in logistics. Meanwhile, a matching problem, concerning with the improvement of picking efficiency in new system, is studied in this paper. The problem is how to reduce the travelling distance of totes between aisles and picking stations. A multi-stage heuristic algorithm is proposed based on statement and model of this problem. The main idea of this algorithm is, with some heuristic strategies based on similarity coefficients, minimizing the transportations of items which can not arrive in the destination picking stations just through direct conveyors. The experimental results based on the cases generated by computers show that the average reduced rate of indirect transport times can reach 14.36% with the application of multi-stage heuristic algorithm. For the cases from a real e-commerce distribution center, the order processing time can be reduced from 11.20 h to 10.06 h with the help of the modified system and the proposed algorithm. In summary, this research proposed a modified system and a multi-stage heuristic algorithm that can reduce the travelling distance of totes effectively and improve the whole performance of e-commerce distribution center.

关键词： e-commerce modified miniload automated storage/retrieval system matching problem multi-stage heuristic algorithm

COMPRESSIBLE VIRTUAL WINDOW ALGORITHM IN PICKING PROCESS CONTROL OF AUTOMATED SORTING SYSTEM

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Chinese Journal of Mechanical Engineering 2008年第3期21卷 41-45页

作者： wu Yaohua ZHANG Yigong wu yingying School of Control Science and Engineering Shandong University Jinan 250061China

Compared to fixed virtual window algorithm （FVWA）, the dynamic virtual window algorithm （DVWA） determines the length of each virtual container according to the sizes of goods of each order, which saves space of virtual containers and improves the picking efficiency. However, the interval of consecutive goods caused by dispensers on conveyor can not be eliminated by DVWA, which limits a further improvement of picking efficiency. In order to solve this problem, a compressible virtual window algorithm （CVWA） is presented. It not only inherits the merit of DVWA but also compresses the length of virtual containers without congestion of order accumulation by advancing the beginning time of order picking and reasonably coordinating the pace of order accumulation. The simulation result proves that the picking efficiency of automated sorting system is greatly improved by CVWA.

关键词： Virtual window algorithm Dynamics Compressibility Picking efficiency

Order dividing optimisation in crane&shuttle-based storage and retrieval system

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Journal of Control and Decision 2023年第2期10卷 215-228页

作者： Wenkai Ma Dong Yang yingying wu Yaohua wu School of Control Science&Engineering Shandong UniversityJinanPeople’s Republic of China Centre for Maritime Studies National University of SingaporeSingaporeSingapore Business School Shandong University of TechnologyZiboPeople’s Republic of China

The crane&shuttle-based storage and retrieval system(C&SBS/RS)is the first automated warehouse technology that supports pallet picking,case picking and item *** the C&SBS/RS,aisle-captive cranes perform pallet picking,while tier-captive shuttles handle cases and items *** balance picking tasks,we propose an order dividing algorithm to fulfil required specific picking *** optimisation objective is to minimise the order line picking ***,we modelled and analyzed the C&SBS/RS and considered single and dual command cycles for each resource(***,rail-guided vehicles,shuttles and lifters)separately according to their respective operation ***,numerical experiments were conducted to analyze impact factors and a real case to verify the power of the proposed order dividing algorithm.

关键词： Automated warehouses unit-load AS/RS SBS/RS analytical and numerical modelling performance analysis

Livelihood Strategy Change and Land Use Change——Case of Danzam Village in Upper Dadu River Watershed,Tibetan Plateau of China

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Chinese Geographical Science 2009年第3期19卷 231-240页

作者： YAN Jianzhong ZHANG Yili ZHANG Liping wu yingying College of Resources and Environment Southwest University Chongqing 400716 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Land use change in rural China since the 1980s, induced by institution reforms, urbanization, industrialization and population increase, has received more attention. However, case studies on how institution reforms affect farmers＇ livelihood strategies and drive land use change are scarce. By means of cropland plots investigations and interviews with farmers, this study examines livelihood strategy change and land use change in Danzam Village of Jinchuan County in the upper Dadu River watershed, eastern Tibetan Plateau, China. The results show that, during the collective system period, as surplus labor forces could not be transferred to the secondary and tertiary industries, they had to choose agricultural involution as their livelihood strategy, then the farmers had to produce more grains by land reclamation, increasing multiple cropping index, improving input of labor, fertilizer, pesticide and adopting advanced agricultural techniques. During the household responsibility system period, as labors being transferred to the secondary and tertiary industries, farmers chose livelihood diversification strategy. Therefore, labor input to grain planting was greatly reduced, which drove the transformation of grain to horticulture, vegetable or wasteland and decrease of multiple cropping index. This study provides a new insight into understanding linkages among institution reforms, livelihood strategy of smallholders and land use change in rural China.

关键词： livelihood strategy land use change agricultural involution upper Dadu River watershed Tibetan Plateau China

A 5D simulation method on post-earthquake repair process of buildings based on BIM

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Earthquake Engineering and Engineering Vibration 2020年第3期19卷 541-560页

作者： Xu Zhen Zhang Furong Jin Wei wu yingying Qi Mingzhu Yang Yajun Beijing Key Laboratory of Urban Underground Space Engineering School of Civil and Resource EngineeringUniversity of Science and Technology BeijingBeijing 100083China

The post-earthquake repair process of buildings is one of the key components of building seismic *** the details of the repair process in advance will benefit the evaluation and decision making for the seismic resilience of *** this end,a five-dimensional(5 D)simulation method on the post-earthquake repair process of buildings is proposed based on building information modeling(BIM),by which the repair activities can be presented in the way associated with a 3 D model,time(denoted as the fourth dimension),and the related costs(denoted as the fifth dimension).First,a decision-making model of repair schemes based on the interval index of the possibility degree is created to determine the optimal post-earthquake repair schemes for a damaged ***,an algorithm based on separate flowrepetitive process is designed to automatically make the repair schedule on a BIM platform according to the determined repair ***,an algorithm of automatic mapping between the components in BIM and their repair schedules is developed,so that a 5 D simulation of a post-earthquake repair process can be implemented.A six-story office building is selected as a case study,and the details of the post-earthquake repair process(e.g.,the costs of labor,material and equipment over the repair time)are presented by the proposed 5 D simulation *** outcome of this study can be used to evaluate the seismic resilience of buildings and also to facilitate the decision making for seismically resilient buildings by providing the detailed guidance of the repair process.

关键词： BIM details repair

Shock Characteristics and Protective Design of Equipment During Spacecraft Docking Process

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Acta Mechanica Solida Sinica 2023年第6期36卷 837-850页

作者： Xu Gao Xianxian He yingying wu Yifeng Dong Jiajing Huo Ying Li Beijing Institute of Spacecraft System Engineering Beijing 100094China School of Naval Architecture Ocean and Energy Power EngineeringWuhan University of TechnologyWuhan 430064China Institute of Advanced Structure Technology Beijing Institute of TechnologyBeijing 100081China

The shock loads generated by spacecraft during docking can cause functional failure and structural damage to aerospace electronic equipment and even lead to catastrophic flight *** is currently a lack of systematic and comprehensive research on the shock environment of spacecraft electronic equipment due to the diversity and complexity of the shock *** this paper,the validity of the finite element model is verified based on the sinusoidal vibration experiment results of the spacecraft reentry *** method of shock dynamic response analysis is used to obtain the shock environment of electronic equipment under different shock *** shock response spectrum is used to describe the shock environment of aerospace electronic *** results show that the resonance frequency error between the sinusoidal vibration experiment and the model is less than 4.06%.When the docking relative speed of the reentry capsule is 2 m/s,the shock response spectrum values of one of the equipment are 30 m^(2)/s,0.67 m/s,and 0.059 m,*** wire rope spring on the mating surface can provide vibration isolation and shock *** increase in spring damping coefficient results in a decrease in the amplitude and time of the vibration *** increase in spring stiffness reduces the input of shock load within a certain *** research results can provide guidance for the design and evaluation of shock environmental adaptability of aerospace electronic equipment.

关键词： Shock environment Shock response spectrum Spacecraft docking Protective design

Synthesis and Herbicidal Activities of Novel Uracil Derivatives Containing Pyrimidinyl Moiety

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Chemical Research in Chinese Universities 2014年第3期30卷 400-404页

作者： HE Leien wu yingying ZHANG Hanyun LIU Manyun SHI Deqing Key Laboratory of Pesticide & Chemical Biology Ministry of Education College of Chemistry Central China Normal University Wuhan 430079 P. R. China

In order to find novel protoporphyrinogen oxidase inhibitors with high efficacy, broad-spectrum activity, and safety to crops, nine title compounds（4a-4i） were designed and synthesized by introducing pyrimidine moiety into the uracil skeleton with commercially herbicide butafenacil as the lead compound. Their structures were con- firmed by 1H NMR, IR, mass spectroscopy and elemental analysis. The bioassay results indicate that most of com- pounds 4 tested exhibit good to excellent herbicidal activities against B. campestris, A. retroflexus, E. crusgalli and D. sanguinalis in pre-emergence treatment at a dose of 1.5 kg/ha（1 ha=10^4 m^2）, for example, compound 4i showed 100% inhibition against the four plants tested in pre-emergence treatment at a dose of 1.5 kg/ha. So, this type of skeleton can be used as a valuable lead compound for the further development of a pre-emergent herbicide.

关键词： Protoporphyrinogen oxidase Uracil Pyrimidine Herbicidal activity

Assessment of desertification sensitivity using an improved MEDALUS model in Northern China

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Research in Cold and Arid Regions 2024年第3期16卷 141-148页

作者： NingJing Tan CaiXia Zhang yingying wu ZhenTing Wang Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China University of Chinese Academy of Sciences Beijing 100049China Research Station of Gobi Desert Ecology and Environment Northwest Institute of Eco-environment and ResourcesChinese Academy of SciencesLanzhouGansu 730000China

Assessment of land sensitivity to desertification is an important step to support desertification monitoring and *** on the Mediterranean Desertification and Land Use(MEDALUS)model,we defined four quality indicators(soil,climate,vegetation and management)to evaluate the sensitivity of land in northern China to *** improved MEDALUS via excluding cities from the areas at risk of desertification by means of defining a threshold value for population *** framework,validated in northern China,further optimizes the model to link priority areas and land restoration programmed to support desertification *** found that the four indicators influenced and restricted each other,which jointly affected the distribution of desertification sensitivity in northern *** spatial distribution of sensitivity in northern China showed large regional differences,with clear boundaries and concentrated distributions of regions with high and low sensitivity;the overall sensitivity decreased,with some areas rated as having moderate,severe,and extremely severe sensitivity changing to slight sensitivity;and the influence weight was much higher for the management quality index than for the climate,vegetation,and soil *** suggests that management was the main factor that affected desertification sensitivity in northern China,and that climate factors exacerbated sensitivity,but the factors that are driving the spatial heterogeneity of the influencing factors need further study。

关键词： Desertification Sensitivity MEDALUS Factor analysis Northern China

Comparative analysis of mitochondrial genome of a deepsea crab Chaceon granulates reveals positive selection and novel genetic features

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Journal of Oceanology and Limnology 2020年第2期38卷 427-437页

作者： ZHANG Bo wu yingying WANG Xin JIANG Wei YIN Jianping LIN Qiang Key Laboratory of Tropical Marine Bio-Resources and Ecology South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510275China Institution of South China Sea Ecology and Environmental Engineering Chinese Academy of SciencesGuangzhou 510275China University of Chinese Academy of Sciences Beijing 100049China Beijing Advanced Sciences and Innovation Center of Chinese Academy of Sciences Beijing 100049China Institute of Oceanology Chinese Academy of SciencesQingdao 266071China

Deep-sea organisms survive in an extremely harsh *** must be some genetic adaptation mechanisms for *** systematically characterized and compared the complete mitochondrial genome(mitogenome)of a deep-sea crab(Chaceon granulates)with those of shallow *** mitogenome of the crab was 16126 bp in length,and encoded 37 genes as most of a metazoan mitogenome,including 13 protein-coding genes(PCGs),22 transfer RNA(tRNA)genes,and 2 ribosomal RNA(rRNA)*** gene arrangement and orientation was conserved in the ***,a unique mitogenome element regulator,the origin of light-strand replication(O L),was firstly predicted in the present crab *** addition,further positive selection analysis showed that two residues(33 S in ND3 and 502 I in ND5)in *** mitogenome were positively selected,indicated the selective evolution of the deep-sea ***,the mitogenome of deep-sea *** showed a unique OL element and positive *** special features would influence the mitochondrial energy metabolism,and be involved in the adaptation of deepsea environment,such as oxygen deficits and low temperatures.

关键词： deep-sea organisms mitochondrial genome adaptation Chaceon granulates