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Scalable Temporal Dimension preserved Tensor Completion for Missing Traffic Data Imputation With Orthogonal Initialization

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IEEE/CAA Journal of Automatica Sinica 2024年第10期11卷 2188-2190页

作者： Hong Chen Mingwei Lin Jiaqi Liu zeshui xu the School of Mathematics and Statistics Fujian Normal University IEEE the college of Computer and Cyber Security Fujian Normal University the Business School Sichuan University

Dear Editor,This letter puts forward a novel scalable temporal dimension preserved tensor completion model based on orthogonal initialization for missing traffic data(MTD) imputation. The MTD imputation acts directly on accessing the traffic state, and affects the traffic management. However, it still faces the following challenges: 1) The MTD imputation is usually formulated as matrix completion or tensor completion, which ignores the information across different dimensions;

关键词：

OrDErED WEIGHTED DISTANCE MEASUrE

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Journal of Systems Science and Systems Engineering 2008年第4期17卷 432-445页

作者： zeshui xu~1 Jian CHEN~2 1 School of economics and management,southeast university,nanjing,Jiangsu 210096,china 2 School of economics and management,Tsinghua university,Beijing,100084,china School of economics and management Southeast University Nanjing Jiangsu China School of economics and management Tsinghua University Beijing China

The aim of this paper is to develop an ordered weighted distance(OWD) measure,which is the generalization of some widely used distance measures,including the normalized Hamming distance, the normalized Euclidean distance,the normalized geometric distance,the max distance,the median distance and the min distance,***,the ordered weighted averaging operator,the generalized ordered weighted aggregation operator,the ordered weighted geometric operator,the averaging operator,the geometric mean operator,the ordered weighted square root operator,the square root operator,the max operator,the median operator and the min operator are also the special cases of the OWD *** methods depending on the input arguments are given to determine the weights associated with the OWD *** prominent characteristic of the OWD measure is that it can relieve(or intensify) the influence of unduly large or unduly small deviations on the aggregation results by assigning them low(or high) *** desirable characteristic makes the OWD measure very suitable to be used in many actual fields,including group decision making,medical diagnosis, data mining,and pattern recognition,***,based on the OWD measure,we develop a group decision making approach,and illustrate it with a numerical example.

关键词： Group decision making ordered weighted distance(OWD) measure aggregation operator

Women’s empowerment and food consumption:Evidence from female-headed households in Tanzania

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Journal of Integrative Agriculture 2024年第2期23卷 457-467页

作者： Mosses Lufuke xu Tian college of economics and management Nanjing Agricultural UniversityNanjing 210095China Department of economics The University of DodomaDodoma 41218Tanzania college of economics and management China Agricultural UniversityBeijing 100083China Academy of Global Food economics and policy China Agricultural UniversityBeijing 100083China

Despite the growing recognition of women’s increasing role in the household and corresponding empowerment programs in sub-Saharan Africa,intensive research on the relationship between women’s influence and household food consumption is *** the most recent(2017-2018)national household survey data from Tanzania,this study examined the influence of women’s empowerment on household food ***,we compared the monthly consumption of eight food categories between female-headed households(FHHs)and male-headed households(MHHs)using both descriptive statistics and the propensity score matching(pSM)***,we adopted the two-stage Linear Expenditure System and Almost Ideal Demand System model(LES-AIDS)to estimate income and price elasticities for the two household *** results show that FHHs consume bread and cereals,fish,oils and fats,vegetables,and confectionery(sugar,jam,honey,chocolate,etc.)more than ***,FHHs have a significantly higher income elasticity of demand for all food groups than *** are also more price elastic than MHHs in meat,fish,oils,fats,sugar,jam,honey,chocolate,etc.

关键词： women’s empowerment food consumption income elasticity price elasticity

Irrigation Water Use Efficiency of Farmers and Its Determinants: Evidence from a Survey in Northwestern china

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Agricultural Sciences in china 2010年第9期9卷 1326-1337页

作者： WANG xue-yuan college of economics, Zhejiang Gongshang university, Hangzhou 310018, p.r.china college of economics Zhejiang Gongshang University Hangzhou 310018 P.R. China

Irrigation water shortage is becoming an increasingly serious problem in agricultural production. In this case, it is very important for policy makers to take measures to improve irrigation water use efficiency, especially in the water-scarce areas. In this paper, the data envelopment analysis （DEA） techniques, based on the concept of input-specific technical efficiency were used to develop farm-level technical efficiency measures and sub-vector efficiencies for irrigation water use. The Tobit regression technique was then adopted to identify the factors that influence irrigation water efficiency differentials under the shortage of water resources. Based on a sample data of 432 wheat farmers in northwestern china, our experimental results of the DEA analysis showed the average technical efficiency of 0.6151. It suggested that wheat farmers could increase their production by as much as 38.49% by using inputs more efficiently. Further, the mean irrigation water efficiency of 0.3065, suggested that wheat farmers could produce the same quantity of wheat using the same quantity of inputs but with 69.35% less water. The results of the Tobit regression analysis showed that the farmer＇s age, income, education level, and the farm size tended to affect the degree of irrigation water efficiency positively, and the channel conditions and different irrigation methods made a significant impact on irrigation water use efficiency. Furthermore, the arrangements of exclusive water property rights and competitive water price mechanism have effectively encouraged the water saving behavior of farmers. These results are valuable for policy makers since it could help to guide policies towards high irrigation water use efficiency.

关键词： irrigation water efficiency determinants data envelopment analysis Tobit regression

基于三角直觉模糊数的多阶段任务系统可靠性评估

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运筹与管理 2024年第5期33卷 1-8页

作者：黄超武小悦林铭炜徐泽水国防科技大学系统工程学院湖南长沙410073 福建师范大学计算机与网络空间安全学院福建福州350117 四川大学商学院四川成都610064

针对多阶段任务系统(phased Mission System,pMS)可靠性评估中对系统或部件退化规律认识不清、主观知识不完备、环境变化等原因造成部件的信息不足或不精确问题,基于三角直觉模糊数(Triangular Intuitionistic Fuzzy Number,TIFN)和二... 详细信息

针对多阶段任务系统(phased Mission System,pMS)可靠性评估中对系统或部件退化规律认识不清、主观知识不完备、环境变化等原因造成部件的信息不足或不精确问题,基于三角直觉模糊数(Triangular Intuitionistic Fuzzy Number,TIFN)和二元决策图(Binary Decision Diagram,BDD)模型,提出了一种pMS可靠性评估方法。首先,定义了TIFN的指数运算法则,证明了其满足的性质;其次,通过多位专家对部件平均故障时间(Mean Time to Failure,MTTF)进行评估,利用TIFN量化专家意见,建立了直觉模糊失效率评估模型,构建了一种计算TIFN的隶属度和非隶属度的方法,根据TIFN的运算法则和指数分布函数定义了部件的模糊失效函数;最后,运用示例说明了该方法的有效性,并与传统pMS-BDD方法、模糊故障树方法和直觉模糊故障树方法进行了对比分析。

关键词：多阶段任务系统(pMS) 可靠性评估三角直觉模糊数(TIFN) 二元决策图(BDD)

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product Form Solution of a Queuing-Inventory System with Lost Sales and Server Vacation

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Journal of Systems Science & Complexity 2024年第2期37卷 729-758页

作者： YUE Dequan ZHANG Yuying xu Xiuli YUE Wuyi School of Science Yanshan UniversityQinhuangdao 066004China School of economics and management Yanshan UniversityQinhuangdao 066004China The Kyoto college of Graduate Studies for Informatics Kyoto City 606-8225Japan

In this study,the authors consider an M/M/1 queuing system with attached inventory under an(s,S)control *** server takes multiple vacations whenever the inventory is *** is assumed that the lead time and the vacation time follow exponential *** authors formulate the model as a quasi-birth-and-dearth(QBD)process and derive the stability condition of the ***,the stationary distribution in product form for the joint process of the queue length,the inventory level,and the server’s status is ***,the conditional distributions of the inventory level when the server is on and operational,and when it is off due to a vacation,are *** the stationary distribution,the authors obtain some performance measures of the *** authors investigate analytically the effect of the server’s vacation on the performance ***,several numerical examples are presented to investigate the effects of some parameters on the performance measures,the optimal policy,and the optimal cost.

关键词： Cost function multiple vacations product form solution queuing-inventory system (s S)control policy

Distributed dynamic task allocation for unmanned aerial vehicle swarm systems:A networked evolutionary game-theoretic approach

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Chinese Journal of Aeronautics 2024年第6期37卷 182-204页

作者： Zhe ZHANG Ju JIANG Haiyan xu Wen-An ZHANG college of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China college of economics and management Nanjing University of Aeronautics and AstronauticsNanjing 211106China college of Information Engineering Zhejiang University of TechnologyHangzhou 310023China

Task allocation is a key aspect of Unmanned Aerial Vehicle(UAV)swarm collaborative *** an continuous increase of UAVs’scale and the complexity and uncertainty of tasks,existing methods have poor performance in computing efficiency,robustness,and realtime allocation,and there is a lack of theoretical analysis on the convergence and optimality of the *** paper presents a novel intelligent framework for distributed decision-making based on the evolutionary game theory to address task allocation for a UAV swarm system in uncertain scenarios.A task allocation model is designed with the local utility of an individual and the global utility of the ***,the paper analytically derives a potential function in the networked evolutionary potential game and proves that the optimal solution of the task allocation problem is a pure strategy Nash equilibrium of a finite strategy ***,a payOff-based Time-Variant Log-linear Learning Algorithm(pOTVLLA)is proposed,which includes a novel learning strategy based on payoffs for an individual and a time-dependent Boltzmann *** former aims to reduce the system’s computational burden and enhance the individual’s effectiveness,while the latter can ensure that the pOTVLLA converges to the optimal Nash equilibrium with a probability of *** simulation results show that the approach is optimal,robust,scalable,and fast adaptable to environmental changes,even in some realistic situations where some UAVs or tasks are likely to be lost and increased,further validating the effectiveness and superiority of the proposed framework and algorithm.

关键词： Task allocation Unmanned Aerial Vehicles(UAV) Game theory Log-linear learning Distributed optimization algorithm

Does Green Food Certification promote agri-food export quality?Evidence from china

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Journal of Integrative Agriculture 2024年第3期23卷 1061-1074页

作者： ping Wei Hongman Liu Chaokai xu Shibin Wen college of economics and management China Agricultural UniversityBeijing 100083China School of public Affairs Zhejiang UniversityHangzhou 310058China

The construction of a food certification system plays a vital role in upgrading export quality, which previous studies have largely overlooked. We match china's industry-level data of Green Food Certification with its HS6-digit export data of agri-food products to quantify the impact of Green Food Certification on export quality. We identify the significant and positive effect of Green Food Certification on export quality. The 2SLS estimation based on instrumental variables and a range of robustness checks confirm the validity and robustness of the benchmark conclusions. Further analysis discloses that Green Food Certification improves export quality by raising agricultural production efficiency and brand premiums. Heterogeneity analysis shows that the effect of Green Food Certification varies across regions, notably improving the quality of agri-food products exported to developed regions and regions with high levels of import supervision. Furthermore, among various product types, Green Food Certification significantly improves the export quality of primary products and products vulnerable to non-tariff measures. The above findings could guide the future development of agri-food quality certification systems, potentially leading to a transformation and promotion of the agri-food trade.

关键词： Green Food Certification agri-food products green transformation export quality food labeling

Improved Data Stream Clustering Method: Incorporating KD-Tree for Typicality and Eccentricity-Based Approach

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Computers, Materials & Continua 2024年第2期78卷 2557-2573页

作者： Dayu xu Jiaming Lu xuyao Zhang Hongtao Zhang college of Mathematics and Computer Science Zhejiang A&F UniversityHangzhou311300China college of economics and management Zhejiang A&F UniversityHangzhou311300China

Data stream clustering is integral to contemporary big data ***,addressing the ongoing influx of data streams efficiently and accurately remains a primary challenge in current *** paper aims to elevate the efficiency and precision of data stream clustering,leveraging the TEDA(Typicality and Eccentricity Data Analysis)algorithm as a foundation,we introduce improvements by integrating a nearest neighbor search algorithm to enhance both the efficiency and accuracy of the *** original TEDA algorithm,grounded in the concept of“Typicality and Eccentricity Data Analytics”,represents an evolving and recursive method that requires no prior *** the algorithm autonomously creates and merges clusters as new data arrives,its efficiency is significantly hindered by the need to traverse all existing clusters upon the arrival of further *** work presents the NS-TEDA(Neighbor Search Based Typicality and Eccentricity Data Analysis)algorithm by incorporating a KD-Tree(K-Dimensional Tree)algorithm integrated with the Scapegoat *** arrival,this ensures that new data points interact solely with clusters in very close *** significantly enhances algorithm efficiency while preventing a single data point from joining too many clusters and mitigating the merging of clusters with high overlap to some *** apply the NS-TEDA algorithm to several well-known datasets,comparing its performance with other data stream clustering algorithms and the original TEDA *** results demonstrate that the proposed algorithm achieves higher accuracy,and its runtime exhibits almost linear dependence on the volume of data,making it more suitable for large-scale data stream analysis research.

关键词： Data stream clustering TEDA KD-tree scapegoat tree