63 results on '"Renqian ZHANG"'
Search Results
2. Resource levelling in repetitive construction projects with interruptions: an integrated approach
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Guyu Dai, Mingjuan Liao, and Renqian Zhang
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construction management ,repetitive construction project ,scheduling ,resource levelling ,work interruption ,optimization ,Building construction ,TH1-9745 - Abstract
Despite the significance of resource levelling, project managers lack various ways to smooth resource usage fluctuation of a repetitive construction project besides changing resource usage. Tolerating interruptions is an effective way to provide flexibility for a schedule but is ignored when solving resource levelling problems. Therefore, this paper investigates the impacts of interruptions on resource usage fluctuation and develops an integrated approach that simultaneously integrates two scheduling adjusting processes: changing resource usage and tolerating interruptions. In this paper, two interruption conditions are proposed to identify which activities are suitable to be interrupted for smoothing resource usage fluctuation. The traditional resource levelling model is modified to a new scheduling model by incorporating interruptions. A two-stage GA-based scheduling algorithm is developed by integrating changing resource usage and tolerating interruptions. A commonly used pipeline project is adopted to illustrate the steps of the proposed approach and demonstrate its effectiveness and superiority through comparison with previous studies. A large-scale project further verifies the usability of the proposed approach. The results confirmed the feasibility to smooth resource usage fluctuation by interruptions, and the integrated approach can achieve a more competitive resource levelling result.
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- 2023
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3. Spike-Train Level Direct Feedback Alignment: Sidestepping Backpropagation for On-Chip Training of Spiking Neural Nets
- Author
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Jeongjun Lee, Renqian Zhang, Wenrui Zhang, Yu Liu, and Peng Li
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spiking neural networks ,backpropagation ,on-chip training ,hardware neural processor ,FPGA ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Spiking neural networks (SNNs) present a promising computing model and enable bio-plausible information processing and event-driven based ultra-low power neuromorphic hardware. However, training SNNs to reach the same performances of conventional deep artificial neural networks (ANNs), particularly with error backpropagation (BP) algorithms, poses a significant challenge due to inherent complex dynamics and non-differentiable spike activities of spiking neurons. In this paper, we present the first study on realizing competitive spike-train level backpropagation (BP) like algorithms to enable on-chip training of SNNs. We propose a novel spike-train level direct feedback alignment (ST-DFA) algorithm, which is much more bio-plausible and hardware friendly than BP. Algorithm and hardware co-optimization and efficient online neural signal computation are explored for on-chip implementation of ST-DFA. On the Xilinx ZC706 FPGA board, the proposed hardware-efficient ST-DFA shows excellent performance vs. overhead tradeoffs for real-world speech and image classification applications. SNN neural processors with on-chip ST-DFA training show competitive classification accuracy of 96.27% for the MNIST dataset with 4× input resolution reduction and 84.88% for the challenging 16-speaker TI46 speech corpus, respectively. Compared to the hardware implementation of the state-of-the-art BP algorithm HM2-BP, the design of the proposed ST-DFA reduces functional resources by 76.7% and backward training latency by 31.6% while gracefully trading off classification performance.
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- 2020
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4. Impacts of Employee Turnover on the Integrated Inventory Model When Overtime Occurs.
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Xuefang Sun and Renqian Zhang
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- 2020
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5. The Impact of Expectation and Disconfirmation on User Experience and Behavior Intention.
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Xiaorui Wang, Ronggang Zhou, and Renqian Zhang
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- 2020
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6. APT-Structure: Efficient Mining of Frequent Patterns.
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Shiwei Zhu, Renqian Zhang, and Guoping Xia
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- 2010
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7. A DSS based on Entropy Method in EIS in Chinese Financial Sectors.
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Renqian Zhang and Hongxun Jiang
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- 2006
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8. Study on the Construction of the Pricing Parameter Model of Aero Engine Digital Control System Test
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Xicai Zhang and Renqian Zhang
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- 2021
9. Multi-Day Waste Collection and Transportation Problems with Selective Collection and Split Delivery
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Luo, Kaiping, primary, Zhao, Wencong, additional, and Renqian, Zhang, additional
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- 2022
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10. New model of the storage location assignment problem considering demand correlation pattern
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Meng Wang, Xing Pan, and Renqian Zhang
- Subjects
Mathematical optimization ,021103 operations research ,General Computer Science ,Heuristic ,Computer science ,0211 other engineering and technologies ,General Engineering ,02 engineering and technology ,Correlation ,Supply chain efficiency ,Simulated annealing ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Routing (electronic design automation) ,Assignment problem - Abstract
Order-picking is the most time- and labor-consuming operation in a warehouse and significantly influences supply chain efficiency. One of the basic methods for improving order-picking efficiency involves assigning storage locations to appropriate items, i.e., the storage location assignment problem (SLAP). In existing studies, most storage assignment methods only consider the properties of individual item rather than the item groups that are usually collectively required. This paper introduces the concept of the demand correlation pattern (DCP) to describe the correlation among items, based on which a new model is constructed to address the SLAP. The model is subsequently reduced using the S-shape routing strategy, and a method for determining DCPs from historical data is proposed. To solve the model, a heuristic and a simulated annealing method are developed. The proposed methods are examined and compared extant methods using both real data collected from an online retailer and numerical instances that are randomly generated. The computational results are discussed.
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- 2019
11. An improved variable neighborhood search algorithm for the solid waste collection and transportation problem with split deliveries
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Renqian Zhang, Xi Yuan, Wencong Zhao, and Kaiping Luo
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021103 operations research ,Computer science ,0211 other engineering and technologies ,02 engineering and technology ,Solid modeling ,Transportation theory ,Simulated annealing ,0202 electrical engineering, electronic engineering, information engineering ,Programming paradigm ,Transportation plan ,020201 artificial intelligence & image processing ,Solid waste collection ,Algorithm ,Variable neighborhood search - Abstract
This study addresses the solid waste collection and transportation problem with split deliveries (SWCTPSD). To minimize the total fleet costs, a mixed-integer programming model is proposed. An improved variable neighborhood search (VNS) algorithm is proposed to obtain a high-quality collection and transportation plan quickly. To enhance the local exploitive ability, the VNS algorithm is hybridized with simulated annealing. The experimental results show that the proposed VNS algorithm is effective.
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- 2021
12. Transglutaminase 3 expression in hepatocellular carcinoma patients: Correlation with tumor features and survival profile
- Author
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Renqian Zhang, Lei Zhan, and Deng Wu
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Carcinoma, Hepatocellular ,Tissue transglutaminase ,Carcinoembryonic antigen ,Biomarkers, Tumor ,Humans ,Medicine ,RNA, Messenger ,Protein kinase B ,Retrospective Studies ,Glycogen Synthase Kinase 3 beta ,Transglutaminases ,Hepatology ,Oncogene ,biology ,business.industry ,Liver Neoplasms ,Gastroenterology ,Prognosis ,medicine.disease ,BCLC Stage ,Hepatocellular carcinoma ,Cancer research ,biology.protein ,Immunohistochemistry ,alpha-Fetoproteins ,business ,Liver cancer - Abstract
BACKGROUND Transglutaminase 3 (TGM3) regulates multiple oncogene pathways (GSK-3β/β-catenin pathway, Akt/ERK pathway, etc.) to promote hepatocellular carcinoma (HCC) cell proliferation, migration and invasion, however, its clinical value for HCC management is still limited. Therefore, we conducted this study to compare the TGM3 expression between tumor tissue and paired adjacent noncancerous tissue, aiming to explore the clinical application of TGM3 in HCC patients. METHODS Totally, 208 HCC patients were enrolled and their clinicopathological features were collected. Then, 208 pairs of HCC specimens and adjacent noncancerous specimens were used to detect TGM3 protein expression by IHC assay and assessed by a semi-quantitative scoring method. Besides, 157 pairs were proposed to detect TGM3 mRNA expression by RT-qPCR. RESULTS Both TGM3 protein (P
- Published
- 2022
13. Spike-Train Level Direct Feedback Alignment: Sidestepping Backpropagation for On-Chip Training of Spiking Neural Nets
- Author
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Yu Liu, Peng Li, Jeong-Jun Lee, Renqian Zhang, and Wenrui Zhang
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Spiking neural network ,Contextual image classification ,Artificial neural network ,business.industry ,Computer science ,General Neuroscience ,Spike train ,Speech corpus ,Pattern recognition ,Backpropagation ,hardware neural processor ,lcsh:RC321-571 ,on-chip training ,spiking neural networks ,Artificial intelligence ,business ,Field-programmable gate array ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,MNIST database ,FPGA ,Neuroscience ,Original Research ,backpropagation - Abstract
Spiking neural networks (SNNs) present a promising computing model and enable bio-plausible information processing and event-driven based ultra-low power neuromorphic hardware. However, training SNNs to reach the same performances of conventional deep artificial neural networks (ANNs), particularly with error backpropagation (BP) algorithms, poses a significant challenge due to inherent complex dynamics and non-differentiable spike activities of spiking neurons. In this paper, we present the first study on realizing competitive spike-train level backpropagation (BP) like algorithms to enable on-chip training of SNNs. We propose a novel spike-train level direct feedback alignment (ST-DFA) algorithm, which is much more bio-plausible and hardware friendly than BP. Algorithm and hardware co-optimization and efficient online neural signal computation are explored for on-chip implementation of ST-DFA. On the Xilinx ZC706 FPGA board, the proposed hardware-efficient ST-DFA shows excellent performance vs. overhead tradeoffs for real-world speech and image classification applications. SNN neural processors with on-chip ST-DFA training show competitive classification accuracy of 96.27% for the MNIST dataset with 4× input resolution reduction and 84.88% for the challenging 16-speaker TI46 speech corpus, respectively. Compared to the hardware implementation of the state-of-the-art BP algorithm HM2-BP, the design of the proposed ST-DFA reduces functional resources by 76.7% and backward training latency by 31.6% while gracefully trading off classification performance.
- Published
- 2020
14. Polynomial algorithm of inventory model with complete backordering and correlated demand caused by cross-selling
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Chen Xiang, Meng Yi, Qi-Qi Wang, and Renqian Zhang
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Economics and Econometrics ,Mathematical optimization ,021103 operations research ,0211 other engineering and technologies ,02 engineering and technology ,Function (mathematics) ,Management Science and Operations Research ,General Business, Management and Accounting ,Polynomial algorithm ,Industrial and Manufacturing Engineering ,03 medical and health sciences ,0302 clinical medicine ,Exact algorithm ,Cross-selling ,Polynomial complexity ,030221 ophthalmology & optometry ,Mathematics - Abstract
In a paper published in the International Journal of Production Economics (IJPE) [Zhang, R., Kaku, I., Xiao, Y., 2012. Model and heuristic algorithm of the joint replenishment problem with complete backordering and correlated demand. International Journal of Production Economics 139 (1), 33–41], the authors proposed a joint replenishment problem (JRP) model with complete backordering and correlated demand caused by cross-selling. The model was transformed into minimizing a function with respect to multiples of a major item's order cycle, and a heuristic algorithm was developed for near-optimal solutions. In this paper, we reinvestigate the problem and analyze the mathematical property of the model to develop an exact algorithm. The algorithm can obtain global optima and exhibits polynomial complexity.
- Published
- 2018
15. Measuring e-service quality and its importance to customer satisfaction and loyalty: an empirical study in a telecom setting
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Ronggang Zhou, Xiaorui Wang, Leyuan Zhang, Haiyan Guo, Renqian Zhang, and Yuhan Shi
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Service (business) ,Service quality ,business.industry ,media_common.quotation_subject ,05 social sciences ,Economics, Econometrics and Finance (miscellaneous) ,02 engineering and technology ,Loyalty business model ,Human-Computer Interaction ,Empirical research ,020204 information systems ,Scale (social sciences) ,0502 economics and business ,Loyalty ,0202 electrical engineering, electronic engineering, information engineering ,050211 marketing ,Customer satisfaction ,Quality (business) ,Business ,Telecommunications ,media_common - Abstract
The important influence of e-service quality (e-SQ) on customer satisfaction and loyalty has been demonstrated in many contexts, but has not been examined in telecom settings yet. The current study aimed to construct a measurement scale for e-SQ in telecom settings, as well as to investigate the relationship between e-SQ, customer satisfaction, and customer loyalty. In this study, we analyzed self-reports from 9249 respondents (74.55% were male) between the ages of 19 and 45. A scale consisting of five user experinece dimensions (functional completeness, performance, interface and interaction quality, content and information, support or service) was developed to measure e-SQ in the telecom industry. The scale was proven reliable and valid. The analysis confirmed a positive relationship between e-SQ, customer satisfaction and loyalty. In addition, e-SQ was found to be a core predictor of customer satisfaction and customer loyalty. Moreover, customer satisfaction emerged as the strongest predictor of customer loyalty.
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- 2018
16. Joint decisions on emission reduction and order quantity by a risk-averse firm under cap-and-trade regulation
- Author
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Qi Qi, Renqian Zhang, and Qingguo Bai
- Subjects
Microeconomics ,Profit (accounting) ,General Computer Science ,CVAR ,Order (exchange) ,Risk aversion ,General Engineering ,Economics ,Emissions trading ,Carbon credit ,Investment (macroeconomics) ,Supply and demand - Abstract
With the implementation of carbon regulations, firmes are facing pressure on emission reduction and need to consider investing in clean equipment and technology to reduce carbon emissions. However, the resulting uncertainty poses risks to operation management, and decision-makers have different risk preferences. This paper considers a risk-averse firm confronted with cap-and-trade regulation and uncertain market demand. The customers are assumed to be environment-friendly, and thus the demand is influenced by carbon emissions. The joint decisions on order quantity and emission reduction levels are investigated under the conditional value-at-risk (CVaR) framework. This research formulates a joint decision model based on the CVaR criterion and explores how a firm’s risk aversion and investment coefficient influence optimal decisions. The findings show that if the investment coefficient of carbon emission reduction is sufficiently small, firms will not trade any carbon credits. This implies that for the effectiveness of the carbon market, the government should continue decreasing the carbon quota with the development of clean technologies. Additionally, the cap-and-trade regulation encourages firms to invest in carbon emission reduction and does not necessarily deplete the risk-averse firm's profit. Particularly, it is found that in the higher trading price of carbon, the optimal emission reduction level is more sensitive to risk aversion than to the order quantity.
- Published
- 2021
17. The newsvendor model with non-zero reference point based on cumulative prospect theory
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Weiguo Fang, Renqian Zhang, and Shou-Rong Li
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021103 operations research ,Cumulative prospect theory ,General Computer Science ,05 social sciences ,0211 other engineering and technologies ,General Engineering ,Zero (complex analysis) ,02 engineering and technology ,Newsvendor model ,Center effect ,Extended newsvendor model ,Prospect theory ,Bellman equation ,0502 economics and business ,Economics ,050207 economics ,Mathematical economics - Abstract
The NV model with non-zero reference point under cumulative prospect theory (CPT).Develop the first-order conditions of the NV model with non-zero reference point.The proposed NV model partially explains the pull-to-center effect. This paper formulates the newsvendor model with a non-zero reference point based on cumulative prospect theory (CPT-based newsvendor model), evaluating the prospect by a piecewise-linear value function (ModelPL). We prove the concavity of the objective function, and therefore, the model is solved by the first-order optimality condition. As a comparison, we further present the newsvendor model based on a piecewise-exponential value function (ModelPE), where the utility curvatures are considered.The results show that for a low-profit item, only ModelPE can explain the pull to center effect that was found by Schweitzer and Cachon (2000), if the reference point is high enough. However, for a high-profit item, both models successfully predict the newsvendors behavior if the newsvendor conceives a non-zero reference point. Thus, prospect theory (PT) should not be excluded as a potential explanation for the pull to center effect of the newsvendors decision.
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- 2017
18. Choosing among hospitals in the subsidized health insurance system of China: A sequential game approach
- Author
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Qiang Wan, Wenhui Zhou, and Renqian Zhang
- Subjects
Government ,021103 operations research ,Information Systems and Management ,Actuarial science ,General Computer Science ,Sequential game ,05 social sciences ,0211 other engineering and technologies ,Subsidy ,02 engineering and technology ,Management Science and Operations Research ,Industrial and Manufacturing Engineering ,Tax revenue ,Modeling and Simulation ,Service level ,0502 economics and business ,Health care reform ,Business ,050207 economics ,China ,Optimal decision - Abstract
Using tax revenues to subsidize health insurance and to achieve safe and effective health services has become an important means of health care reform for governments. However, how to select designated hospitals or specific medical facilities that allow as many patients as possible to afford medicine and treatment is a difficult problem that the governments of some countries must face. In this paper, we try to address the problem by constructing a sequential game model and presenting an application under China's new cooperative medical scheme (NCMS). We consider a market with two different hospital quality levels and give the optimal decision of the government. Our results show the following: (1) more NCMS-designated hospitals approved by the government may not guarantee that more patients obtain medical services, which depends on the financial budget and the medical service levels. When the budget is large enough, subsidizing both levels of hospitals is optimal. Otherwise, the government should approve only one level. (2) A larger difference between the medical service levels of different hospitals leads to a smaller number of patients who can obtain medical services. In other words, a large service level difference between hospitals harms the goal of the government. (3) The number of hospital patients increases as the medical budget increases.
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- 2017
19. Pricing and coordination of a dual-channel supply chain with consideration of carbon tax
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Jing Wang, Renqian Zhang, and Qi Qi
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021103 operations research ,Carbon tax ,Supply chain ,05 social sciences ,Control (management) ,0211 other engineering and technologies ,ComputingMilieux_LEGALASPECTSOFCOMPUTING ,02 engineering and technology ,Decentralised system ,Dual (category theory) ,Transfer payment ,Order (exchange) ,Greenhouse gas ,0502 economics and business ,Business ,050203 business & management ,Industrial organization - Abstract
In order to protect environment and control carbon emissions, some governments have implemented low-carbon policies including carbon tax. The firms in the supply chain have to make decisions under these policies. We explore the pricing and coordination of a dual-channel supply chain under carbon tax. We obtain optimal prices and corresponding profits in centralized and decentralized systems and show the effects of carbon tax on carbon emissions and profits. In addition, we employ two price discount contracts to improve the performance of decentralized system and propose a transfer payment mechanism to make a win-win for supplier and retailer. This research bridges the gap in existing literature and gives some valuable insights for both firms' decision makers and governments' policy makers.
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- 2019
20. Estimation of Jointly Normally Distributed Demand for Cross-Selling Items in Inventory Systems with Lost Sales
- Author
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Jie Hu, Renqian Zhang, Yi-Ye Zhang, Qi-Qi Wang, and Haitao Zheng
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0209 industrial biotechnology ,021103 operations research ,Article Subject ,General Mathematics ,lcsh:Mathematics ,0211 other engineering and technologies ,General Engineering ,Estimator ,02 engineering and technology ,Discount points ,lcsh:QA1-939 ,Censoring (statistics) ,Standard deviation ,020901 industrial engineering & automation ,Safety stock ,Cross-selling ,Sample size determination ,Complete information ,lcsh:TA1-2040 ,Econometrics ,lcsh:Engineering (General). Civil engineering (General) ,Mathematics - Abstract
Demand estimation is often confronted with incomplete information of censored demand because of lost sales. Many estimators have been proposed to deal with lost sales when estimating the parameters of demand distribution. This study introduces the cross-selling effect into estimations, where two items are cross-sold because of the positive externality in a newsvendor-type inventory system. We propose an approach to estimate the parameters of a jointly normally distributed demand for two cross-selling items based on an iterative framework considering lost sales. Computational results based on more than two million numerical examples show that our estimator achieves high precision. Compared with the point estimations without lost sales, all the relative errors of the estimations of demand expectation, standard deviation, and correlation coefficient are no larger than 2% on average if the sample size is no smaller than 800. In particular, for demand expectation, the error is smaller than 1% if the comprehensive censoring level is no larger than four standard deviations (implying a 2σ-level of safety stock for each item), even if the sample size decreases to 50. This implies that the demand estimator should be competent in modern inventory systems that are rich in data.
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- 2019
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21. Improving order-picking operation through efficient storage location assignment: A new approach
- Author
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Meng Wang, Kun Fan, and Renqian Zhang
- Subjects
Order picking ,021103 operations research ,General Computer Science ,Computer science ,Iterative method ,Scale (chemistry) ,media_common.quotation_subject ,0211 other engineering and technologies ,General Engineering ,02 engineering and technology ,computer.software_genre ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Quality (business) ,Data mining ,Heuristics ,Assignment problem ,computer ,media_common - Abstract
Fast development of online retail industry requires customer orders to be fulfilled within tight windows, where order-picking, the most time-consuming and labor-intensive activity in warehouses, plays an important role. One of the basic ways to improve order-picking operation is assigning storage locations to appropriate items. The storage location assignment problem is in general NP-hard and is mainly solved by heuristics which usually suffer from limited solution quality or high computational effort, especially for large scale problems. In literature, most studies make the storage assignment decisions according to item properties, such as turnover or correlation, which are statistically extracted from item orders. These storage methods follow a data → concept → assign decision mechanism and may ignore useful data characteristics that are not conceptualized. This paper presents a new approach to improve the order-picking operation, which directly uses item orders to make the decisions without any statistical treatments, i.e., following a data → assign mechanism. The concept of good move pair is introduced to quickly find a better assignment through directly exploiting data characteristics of item orders, and an iterative algorithm is developed to minimize the total travel distance. We evaluate the algorithm on real data and numerical instances, and compare its performance with extant methods in the literature. The results show that the proposed method significantly outperforms other methods in most cases. We also extend the algorithm to the case of high-level warehouses and examine its effectiveness.
- Published
- 2020
22. Integrated Production-Delivery Lot Sizing Model with Limited Production Capacity and Transportation Cost considering Overtime Work and Maintenance Time
- Author
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Renqian Zhang and Xuefang Sun
- Subjects
021103 operations research ,Transportation cost ,Article Subject ,Computer science ,General Mathematics ,Supply chain ,lcsh:Mathematics ,05 social sciences ,0211 other engineering and technologies ,General Engineering ,Sensitive analysis ,02 engineering and technology ,Overtime work ,lcsh:QA1-939 ,Sizing ,Reliability engineering ,Order (business) ,lcsh:TA1-2040 ,0502 economics and business ,Production (economics) ,Integrated production ,lcsh:Engineering (General). Civil engineering (General) ,050203 business & management - Abstract
An extension of the integrated production-delivery lot sizing model with limited production capacity and transportation cost is investigated. We introduce the factor of overtime work into the model to improve the manufacturer’s production. In addition, when finishing a lot, the manufacturer has maintenance time to maintain and repair equipment for ensuring that the supply chain is operating continuously. By analyzing the integrated model, the solution procedure is provided to determine the optimal delivery and order policy. We conduct a numerical experiment and give sensitive analysis by varying some parameters to illustrate the problem and its solution procedure.
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- 2018
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23. Non-permutation flow shop scheduling with order acceptance and weighted tardiness
- Author
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Renqian Zhang, Abdullah Konak, Yiyong Xiao, and Yingying Yuan
- Subjects
Mathematical optimization ,Job shop scheduling ,Heuristic (computer science) ,Applied Mathematics ,Tardiness ,AMPL ,Flow shop scheduling ,Computational Mathematics ,Permutation ,Genetic algorithm ,computer ,Integer programming ,Mathematics ,computer.programming_language - Abstract
Model the problem of non-permutation flow shop scheduling with order acceptance.The model is transformed to linear MIP that is optimally solved by commercial solver.Theorems that are favorable for developing algorithms are presented.An efficient two-phase genetic algorithm (TP-GA) is proposed.The heuristic yields high quality non-permutation solutions. This paper studies the non-permutation solution for the problem of flow shop scheduling with order acceptance and weighted tardiness (FSS-OAWT). We formulate the problem as a linear mixed integer programming (LMIP) model that can be optimally solved by AMPL/CPLEX for small-sized problems. In addition, a non-linear integer programming (NIP) model is presented to design heuristic algorithms. A two-phase genetic algorithm (TP-GA) is developed to solve the problem of medium and large sizes based on the NIP model. The properties of FSS-OAWT are investigated and several theorems for permutation and non-permutation optimum are provided. The performance of the TP-GA is studied through rigorous computational experiments using a large number of numeric instances. The LMIP model is used to demonstrate the differences between permutation and non-permutation solutions to the FSS-OAWT problem. The results show that a considerably large portion of the instances have only an optimal non-permutation schedule (e.g., 43.3% for small-sized), and the proposed TP-GA algorithms are effective in solving the FSS-OAWT problems of various scales (small, medium, and large) with both permutation and non-permutation solutions.
- Published
- 2015
24. The multi-item newsvendor model with cross-selling and the solution when demand is jointly normally distributed
- Author
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Renqian Zhang, Wenhui Zhou, Lan Kang Zhang, Romesh Saigal, and Hui Wen Wang
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TheoryofComputation_MISCELLANEOUS ,Effective demand ,Mathematical optimization ,Information Systems and Management ,General Computer Science ,Management Science and Operations Research ,Newsvendor model ,Industrial and Manufacturing Engineering ,Multi item ,Extended newsvendor model ,symbols.namesake ,Cross-selling ,Nash equilibrium ,Modeling and Simulation ,Economics ,symbols ,Uniqueness ,Stock (geology) - Abstract
Products are often demanded in tandem because of the cross-selling effect. The demand for an item can increase if sales of its cross-selling-associated items are achieved or decrease when the associated items are out of stock, resulting in lost sales. Therefore, a joint inventory policy should be pursued in a cross-selling system. This paper introduces customer-driven cross-selling into centralized and competitive newsvendor (NV) models by representing an item’s effective demand as a function of other items’ order quantities. We derive first-order optimality conditions for the centralized model in addition to pure-strategy Nash equilibrium conditions and uniqueness conditions of the equilibria for the competitive model. We further develop gradient-based (GB) and iteration-based (IB) algorithms to solve the centralized and competitive models, respectively. A computational study verifies the effectiveness of the proposed algorithms. The computational results show that a larger cross-selling effect leads to a larger order quantity in a centralized NV model but a smaller order quantity in a competitive NV model, and a larger positive correlation between items’ demands leads to higher profits with smaller order quantities in both models. Moreover, NVs will order more items if the demand variance is greater, however resulting in lower profits. In a competitive situation, one will prefer smaller order quantities than in a centralized decision situation.
- Published
- 2014
25. A two-stage queueing network on form postponement supply chain with correlated demands
- Author
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Weixiang Huang, Wenhui Zhou, and Renqian Zhang
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Inventory control ,Queueing theory ,Mathematical optimization ,Markov chain ,Computer science ,Applied Mathematics ,Modeling and Simulation ,Mass customization ,Postponement ,Supply chain ,Matrix geometric method ,Variance (accounting) - Abstract
To ease the conflict between quick response and product variety, more and more business models are developed in supply chains. Among these, the form postponement (FP) strategy is an efficient tool and has been widely adopted. To the supply chain with FP strategy, the design mostly involves two problems: determination of customer order decoupling point (CODP) position and semi-finished product inventory control. In this paper, we develop a two-stage tandem queueing network with MAP arrival to address this issue. Particularly, we introduce a Markov arrival process (MAP) to characterize the correlation of the demand. By using of matrix geometric method, we derive several performance measure of the supply chain, such as inventory level and unfill rate. Our numerical examples show that both the variance and the correlation coefficient of the demand lead to more delayed CODP position and more total cost.
- Published
- 2014
26. A variable neighborhood search with an effective local search for uncapacitated multilevel lot-sizing problems
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Ikou Kaku, Renqian Zhang, Yuchun Xu, Qiuhong Zhao, and Yiyong Xiao
- Subjects
Mathematical optimization ,Information Systems and Management ,General Computer Science ,business.industry ,Management Science and Operations Research ,Industrial and Manufacturing Engineering ,Sizing ,Tree traversal ,Search engine ,Modeling and Simulation ,Benchmark (computing) ,Local search (optimization) ,business ,Metaheuristic ,Variable neighborhood search ,Mathematics - Abstract
In this study, we improved the variable neighborhood search (VNS) algorithm for solving uncapacitated multilevel lot-sizing (MLLS) problems. The improvement is twofold. First, we developed an effective local search method known as the Ancestors Depth-first Traversal Search (ADTS), which can be embedded in the VNS to significantly improve the solution quality. Second, we proposed a common and efficient approach for the rapid calculation of the cost change for the VNS and other generate-and-test algorithms. The new VNS algorithm was tested against 176 benchmark problems of different scales (small, medium, and large). The experimental results show that the new VNS algorithm outperforms all of the existing algorithms in the literature for solving uncapacitated MLLS problems because it was able to find all optimal solutions (100%) for 96 small-sized problems and new best-known solutions for 5 of 40 medium-sized problems and for 30 of 40 large-sized problems.
- Published
- 2014
27. Combustion synthesis of Zn1−xCdxS and its photodegradation performance of methylene blue
- Author
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Jiaxing Liu, Xipeng Pu, Jianxiu Liu, Renqian Zhang, and Dafeng Zhang
- Subjects
Materials science ,Photoluminescence ,Absorption spectroscopy ,Mechanical Engineering ,Inorganic chemistry ,Analytical chemistry ,Condensed Matter Physics ,Absorbance ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,Zinc nitrate ,Cadmium nitrate ,General Materials Science ,Luminescence ,Absorption (electromagnetic radiation) ,Powder diffraction - Abstract
Zn1−xCdxS (x=0–1.0) powders were synthesized by a simple combustion method using cadmium nitrate, zinc nitrate and thiourea as raw materials. The structures, morphologies, absorbance, luminescence and photocatalytic properties of the samples were studied by X-ray powder diffraction, transmission electron microscopy, ultraviolet–visible spectrophotometry and photoluminescence. The results show that all Zn1−xCdxS samples exhibit hexagonal structure and no metastable cubic phase is obtained. With increasing content of Cd, red-shifts are observed in both the absorption edges of UV–vis absorption spectra and emission bands of photoluminescence spectra. Among all Zn1−xCdxS samples, CdS shows the best visible-light photocatalytic performance due to its narrow bandgap.
- Published
- 2014
28. A queuing model on supply chain with the form postponement strategy
- Author
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Wenhui Zhou, Renqian Zhang, and Yong-Wu Zhou
- Subjects
Engineering ,Queueing theory ,General Computer Science ,Operations research ,business.industry ,Total cost ,Postponement ,Supply chain ,General Engineering ,Poisson distribution ,Product (business) ,symbols.namesake ,Order (business) ,Service level ,symbols ,Operations management ,business - Abstract
The form postponement (FP) strategy is an important strategy for manufacturing firms to utilize to achieve a quick response to customer needs while keeping low inventory levels of finished products. It is an important and difficult task to design a supply chain that uses FP strategy to mitigate the conflict between inventory level and service level. To this end, we develop a two-stage tandem queuing network to model the supply chain. The first stage is the manufacturing process of the undifferentiated semi-finished product, which is produced on a Make-To-Stock basis: the inventory is controlled by base-stock policy. The second stage is the customization process based on customers' specified requirements. There are two types of order: ordinary order and special order. The former can be met by customizing from semi-finished product, while the latter must be entirely customized beginning from the first stage. The customer orders arrive according to a Poisson process. We first derive the inventory level and fill rate, and then present a total cost model. It turns out that the model is intractable due to the Poisson distribution in the objective function. To analytically solve the problem, we use normal distribution as an approximation of the Poisson distribution, which works well when the parameter of the Poisson distribution is quite large. Finally, some numerical experiments are conducted and managerial insights are offered based on the numerical results.
- Published
- 2013
29. The development of Markov random field theory and applications on image segmentation algorithm
- Author
-
Sirui Fu, Yuru Huang, and Renqian Zhang
- Subjects
Markov random field ,business.industry ,Computer science ,Segmentation-based object categorization ,020209 energy ,ComputingMethodologies_IMAGEPROCESSINGANDCOMPUTERVISION ,Scale-space segmentation ,Pattern recognition ,02 engineering and technology ,Image segmentation ,Minimum spanning tree-based segmentation ,Image texture ,Region growing ,Computer Science::Computer Vision and Pattern Recognition ,0202 electrical engineering, electronic engineering, information engineering ,020201 artificial intelligence & image processing ,Computer vision ,Artificial intelligence ,business ,Connected-component labeling - Abstract
Image segmentation algorithm is to divide the images into several regions with specific and unique characteristics, and is an important technology to extract the interested target. Image segmentation is the key step to realize the research from general image processing into image analysis, and is vital preprocessing method of image recognition and computer vision. We cannot obtain correct recognition if we do not have correct segmentation. Nevertheless, the only basis of segmentation process is brightness or color of pixels in an image. In the processing of computer automatic segmentation, we experience several problems, such as uneven illumination, effect of noise, indistinct part in image, and shadow, and these factors may cause false segmentation. In order to overcome the disadvantages of the traditional segmentation algorithm, in this paper, we propose a novel segmentation algorithm based on Markov Random Field. The segmentation algorithm proposed in this paper is based on Markov Random Field Mode and Bayesian theory, and we determine the objective function in image segmentation problem on the basis of optimality criterion of statistical decision and estimation theory. Some optimization algorithms are used to obtain the maximum possible distribution of Markov Random Field which satisfy these conditions. The experimental result reflects the effectiveness and robustness of our algorithm. As a supplement, we analyze the development trend of the Markov Random Field theory.
- Published
- 2016
30. Inventory Model with Partial Backordering When Backordered Customers Delay Purchase after Stockout-Restoration
- Author
-
Yan-Liang Wu, Wei-Guo Fang, Renqian Zhang, and Wenhui Zhou
- Subjects
Mathematical optimization ,021103 operations research ,Article Subject ,Computer science ,General Mathematics ,Stockout ,lcsh:Mathematics ,05 social sciences ,0211 other engineering and technologies ,General Engineering ,Holding cost ,02 engineering and technology ,lcsh:QA1-939 ,Inventory cost ,Order (business) ,lcsh:TA1-2040 ,0502 economics and business ,Economic order quantity ,lcsh:Engineering (General). Civil engineering (General) ,050203 business & management - Abstract
Many inventory models with partial backordering assume that the backordered demand must be filled instantly after stockout restoration. In practice, however, the backordered customers may successively revisit the store because of the purchase delay behavior, producing a limited backorder demand rate and resulting in an extra inventory holding cost. Hence, in this paper we formulate the inventory model with partial backordering considering the purchase delay of the backordered customers and assuming that the backorder demand rate is proportional to the remaining backordered demand. Particularly, we model the problem by introducing a new inventory cost component of holding the backordered items, which has not been considered in the existing models. We propose an algorithm with a two-layer structure based on Lipschitz Optimization (LO) to minimize the total inventory cost. Numerical experiments show that the proposed algorithm outperforms two benchmarks in both optimality and efficiency. We also observe that the earlier the backordered customer revisits the store, the smaller the inventory cost and the fill rate are, but the longer the order cycle is. In addition, if the backordered customers revisit the store without too much delay, the basic EOQ with partial backordering approximates our model very well.
- Published
- 2016
31. Model and heuristic algorithm of the joint replenishment problem with complete backordering and correlated demand
- Author
-
Ikou Kaku, Yiyong Xiao, and Renqian Zhang
- Subjects
Economics and Econometrics ,Mathematical optimization ,Heuristic (computer science) ,Holding cost ,Function (mathematics) ,Management Science and Operations Research ,General Business, Management and Accounting ,Industrial and Manufacturing Engineering ,Cross-selling ,Order (business) ,Economics ,Operations management ,Cycle count ,Multiple ,Integer (computer science) - Abstract
In practice, demands for items are often correlated with each other because of cross-selling effects. Traditional inventory models hold the assumption that demands are independent, which may lead to the risk of misestimating the inventory cost of associated items. This paper addresses a multi-item inventory system where demands for some minor items are correlated with that for a major item. Because of the cross-selling, demand for minor items may either be raised by the sales of the major item or be pulled down by the unsatisfied demands for the major item. Thus, a joint inventory policy considering correlations across items should be pursued. Considering general integer policy, we propose a joint replenishment problem (JRP) model with complete backordering and correlated demand. Through the use of derivatives the model is transformed to minimize a cost function with respect to multiples of the major item's order cycle. Given that the optimal solution should offer a trade-off between the ordering cost and the inventory holding cost of each item, we develop a heuristic algorithm by adjusting the replenishment frequencies of minor items to solve the model. The heuristic is tested by simulated numerical examples and shows satisfactory results.
- Published
- 2012
32. Neighborhood search techniques for solving uncapacitated multilevel lot-sizing problems
- Author
-
Renqian Zhang, Yiyong Xiao, Ikou Kaku, and Qiuhong Zhao
- Subjects
Mathematical optimization ,General Computer Science ,business.industry ,Iterated function ,Modeling and Simulation ,Neighborhood search ,Local search (optimization) ,Management Science and Operations Research ,business ,Sizing ,Mathematics - Abstract
In this paper, several neighborhood search techniques for solving uncapacitated multilevel lot-sizing problems are investigated. We introduce three indexes: distance, changing range, and changing level that have great influence on the searching efficacy of neighborhood search techniques. These insights can help develop more efficient heuristic algorithms. As a result, we have developed an iterated neighborhood search (INS) algorithm that is very simple but that demonstrates good performance when tested against 176 benchmark instances under different scales (small, medium, and large), with 25 instances having been updated with new best known solutions in the computing experiments.
- Published
- 2012
33. A reduced variable neighborhood search algorithm for uncapacitated multilevel lot-sizing problems
- Author
-
Ikou Kaku, Yiyong Xiao, Qiuhong Zhao, and Renqian Zhang
- Subjects
Information Systems and Management ,Material requirements planning ,General Computer Science ,Management Science and Operations Research ,Industrial and Manufacturing Engineering ,Production planning ,Search algorithm ,Robustness (computer science) ,Modeling and Simulation ,Build to stock ,Benchmark (computing) ,Metaheuristic ,Algorithm ,Variable neighborhood search ,Mathematics - Abstract
Multilevel lot-sizing (MLLS) problems, which involve complicated product structures with interdependence among the items, play an important role in the material requirement planning (MRP) system of modern manufacturing/assembling lines. In this paper, we present a reduced variable neighborhood search (RVNS) algorithm and several implemental techniques for solving uncapacitated MLLS problems. Computational experiments are carried out on three classes of benchmark instances under different scales (small, medium, and large). Compared with the existing literature, RVNS shows good performance and robustness on a total of 176 tested instances. For the 96 small-sized instances, the RVNS algorithm can find 100% of the optimal solutions in less computational time; for the 40 medium-sized and the 40 large-sized instances, the RVNS algorithm is competitive against other methods, enjoying good effectiveness as well as high computational efficiency. In the calculations, RVNS updated 7 (17.5%) best known solutions for the medium-sized instances and 16 (40%) best known solutions for the large-sized instances.
- Published
- 2011
34. A new approach of inventory classification based on loss profit
- Author
-
Ikou Kaku, Renqian Zhang, and Yiyong Xiao
- Subjects
Inventory control ,Operations research ,Association rule learning ,Computer science ,Supply chain ,General Engineering ,Stock-taking ,Computer Science Applications ,Inventory valuation ,Production planning ,Stock keeping unit ,Artificial Intelligence ,Perpetual inventory ,Cycle count - Abstract
Modern production planning and inventory control has been developed in order to treat more practical and more complicated circumstances, such as researching supply chain instead of single stock point; multi-items with correlation instead of single item and so on. In this paper, how to classify inventory items which are correlated each other is discussed by using the concept of 'cross-selling effect'. In history, the ABC classification is usually used for inventory items aggregation because the number of inventory items is so large that it is not computationally feasible to set stock and service control guidelines for each individual item. A fundamental principle in ABC classification is that ranking all inventory items with respect to a notion of profit based on historical transactions. The difficulty is that the profit of one item not only comes from its own sales, but also from its influence on the sales of other items or reverse, i.e., the 'cross-selling effect'. We had previously developed a classification approach for inventory items by using the association rules to deal with the 'cross-selling effect' and found that a very different classification can be obtained when comparing with traditional ABC classification. However, the 'cross-selling effect' may be considered in different ways. In this paper, a new consideration of inventory classification based on loss rule is presented. The lost profit of item/itemset with 'cross-selling effect' is discussed and defined as criterion for evaluating of importance of item, based on which new algorithms on classifying inventory items, also on discovering maximum profit item selection, are presented. A simple example is used to explain the new algorithm, and large amount of empirical experiments, both on real database collected from Japanese convenient store and on downloaded benchmark database, are implemented to evaluate the performances on effectiveness and utility. The results show that the proposed approach in this paper can gain a well insight into the cross-selling effect among items and is applicable for large-sized transaction database.
- Published
- 2011
35. A variable neighborhood search based approach for uncapacitated multilevel lot-sizing problems
- Author
-
Renqian Zhang, Ikou Kaku, Qiuhong Zhao, and Yiyong Xiao
- Subjects
Mathematical optimization ,General Computer Science ,Component (UML) ,General Engineering ,Neighborhood search ,Structure (category theory) ,Benchmark (computing) ,Metaheuristic ,Variable neighborhood search ,Sizing ,Mathematics - Abstract
In this paper, an effective approach based on the variable neighborhood search (VNS) algorithm is presented to solve the uncapacitated multilevel lot-sizing (MLLS) problems with component commonality and multiple end-items. A neighborhood structure for the MLLS problem is defined, and two kinds of solution move policies, i.e., move at first improvement (MAFI) and move at best improvement (MABI), are used in the algorithm. A new rule called Setup shifting is developed to conduct a more efficient neighborhood search for the MLLS problems. Computational studies are carried out on two sets of benchmark problems. The experimental results show that the VNS algorithm is capable of solving MLLS problems with good optimality and high computational efficiency as well, outperforming most of the existing algorithms in comparison.
- Published
- 2011
36. Scenario-based Stochastic Capacity Planning Model and Decision Risk Analysis
- Author
-
Renqian Zhang and Ru-ping Wang
- Subjects
Risk analysis ,Actuarial science ,Capacity planning ,Stochastic investment model ,Operations research ,Stochastic modelling ,Computer science ,Financial risk ,Downside risk ,Revenue ,Supply and demand - Abstract
To study the capacity planning problem under uncertainty in which market demand and product price are stochastic, multi period capacity planning model based on scenario was investigated in this paper. Two models were proposed: one is a prearranged planning model in which the capacity investment plan do not change with the stochastic market demand, and the other is an adaptive planning model in which capacity investment plan could trace the evolution progress of the stochastic market demand. The computational study compared the decision results of both models, which reveals that the adaptive planning model could suggest better decision. Moreover, based on downside risk analysis, the investment risk of stochastic capacity planning has been investigated, and a prearranged capacity planning model considering the expected downside risk of the objective revenue was proposed. In the model, a constraint of expected downside risk is added to the initial stochastic model to reflect the decision-maker's risk preference. Whether to consider the risk or not will result in different decisions, which, in the computational study, were compared.
- Published
- 2009
37. Solving a Class of Job-Shop Scheduling Problem based on Improved BPSO Algorithm
- Author
-
Kun Fan, Guo-ping Xia, and Renqian Zhang
- Subjects
Structure (mathematical logic) ,Constraint (information theory) ,Mathematical optimization ,Constraint algorithm ,Job shop scheduling ,Process (computing) ,Machine shop ,Flow shop scheduling ,Function (mathematics) ,Algorithm ,Mathematics - Abstract
Analyzing the special job shop scheduling problem of a large-scale machine shop, considering workers operational qualification and characteristics of discretely concurrent production, a novel mathematical model has been proposed to meet actual production. In addition, an improved binary particle swarm optimization (BPSO) algorithm has been developed for solving the problem of arranging m workers to process n structures, to optimize the minimum completion time of the jobs. In this improved BPSO, a new method of making initial particles has been presented for searching the optimum particle in the feasible dimensional problem space. Besides, importing memory base, modifying Sig function, and considering constraint condition have been used in the algorithm for making updated particles meet the constraint equation of the mathematical model. The research on the algorithm examples demonstrates that the improved BPSO algorithm is effective and can achieve good results. Moreover, the mathematical model has wide application in discrete manufacture.
- Published
- 2007
38. Research on Capacity Planning under Stochastic Production and Uncertain Demand
- Author
-
Renqian Zhang
- Subjects
Mathematical optimization ,Schedule ,Capacity planning ,Heuristic (computer science) ,Genetic algorithm ,Production (economics) ,Stochastic optimization ,Decision problem ,Nonlinear programming ,Mathematics - Abstract
The main task of the capacity planning decision is to determine an optimal schedule to replace older machines, equipments or activity centers by newer ones. Traditionally, uncertain factors are seldom considered in capacity expansion because of an approximation view in medium- and long-term decision-making. However, in an uncertain market and stochastic production environment, the influences of stochastic factors should not be neglected entirely. To study the stochastic factors' influences on capacity planning decision, a stochastic capacity expansion model is built in this article. The model's objective is to minimize the production and capacity expansion cost. There are two kinds of stochastic factors to be considered: uncertain market demand and consumption of stochastic production capacity. For solving this model, the constraints of uncertain demand are transformed into equivalent deterministic constraints, using the stochastic two-stage model. The constraints of stochastic capacity are transformed into equivalent deterministic formulation, based on Chance Constrained Programming (CCP). Consequently, the stochastic capacity planning model is transformed into a deterministic one, which has a structure where the Product-Mix decision is nested in the capacity planning model. To solve this two-tier model, a heuristic algorithm that combines the Genetic Algorithm (GA) and the Primal-Dual algorithm of Nonlinear Programming, is produced. In the heuristic, GA is used to optimize the capacity decision variables and the Primal-Dual method is used to solve a Product-Mix decision problem with quadratic constraints. A numerical example is constructed for demonstrating the model and the algorithm. The results and analysis are provided.
- Published
- 2007
39. [Case of chronic diarrhea]
- Author
-
Renqian, Zhang, Jiange, Wang, and Zhiheng, Zhao
- Subjects
Diarrhea ,Chronic Disease ,Acupuncture Therapy ,Humans ,Female ,Middle Aged ,Acupuncture Points - Published
- 2015
40. Red Collar Group in Qingdao—High-End Clothing Customization Service
- Author
-
Jun Yao, Jing Wang, Hengshan Zong, Renqian Zhang, and Guozhu Jia
- Subjects
Craft ,Service (business) ,business.industry ,Mass customization ,Production (economics) ,Business ,Business model ,Marketing ,Clothing ,Productivity ,Supply and demand - Abstract
With the increase of social productivity, the garment industry changed from the traditional hand-made craft into industrial mass production of processing pipeline, which greatly improve the efficiency of production of clothing and shorten the production cycle to meet the growing market demand for clothing. However, with the improvement of people’s living standards, demand for personalized clothing increases and therefore, a large-scale standardized production of clothing is no longer suitable for the development of the market. Although high varieties and low volume of clothing production model meet the individual needs of people in some extent, this model is making choices after producing, trying to use the series and various styles of clothing to replace personalized products. First, it’s impossible to meet the individual needs of all customers.
- Published
- 2015
41. Tongfang Energy Engineering Technology Co., Ltd.—Energy Management Contract Service
- Author
-
Zhen Chen, Renqian Zhang, and Jing Wang
- Subjects
Engineering management ,Energy management ,business.industry ,Information technology ,Customer satisfaction ,Manufacturing enterprises ,Business ,IBM ,Value chain ,Energy engineering ,Profit (economics) ,Industrial organization - Abstract
As the margin of manufacturing declines and customers’ demand for products rises, more and more manufacturing enterprises in the world no longer just focus on the production of physical products, but also explore a series of services oriented to customers besides the sale of products, so as to create profits and improve customer satisfaction. Service is playing an increasingly significant role in the value chain of manufacturing, creating a new source of profit for manufacturing enterprises. Servitization of manufacturing has become one of the development trend of manufacturing in current world. By adopting a series of measures, IBM has achieved the transition from a manufacturing enterprise into one specializing in information technology and business solutions.
- Published
- 2015
42. Haier Group—Interactive Design and Manufacturing for Intelligent Home
- Author
-
Lijuan Cheng, Guozhu Jia, Renqian Zhang, Jun Yao, and Jing Wang
- Subjects
Product innovation ,business.industry ,Group (mathematics) ,Interactive design ,Real estate ,Business ,Home appliance ,China ,Tertiary sector of the economy ,Manufacturing engineering - Abstract
After the Chinese Reform and Open-up, by virtue of the incredible manufacturing capacity and the continuous product innovation, “Made in China” products increased rapidly and have become an indispensable part of the global economy.
- Published
- 2015
43. Partial backordering EOQ with a limited backordered demand rate
- Author
-
Yan Gu, Renqian Zhang, and Lingyun Zhao
- Subjects
Mathematical optimization ,Demand rate ,Economic order quantity ,Mathematics - Published
- 2014
44. Parameter selection optimization for parametric cost estimation based on Simulated Annealing
- Author
-
Yiyong Xiao, Xiao-yan Xing, and Renqian Zhang
- Subjects
Mathematical optimization ,Cost estimate ,Estimation theory ,Computer science ,Mean squared prediction error ,Simulated annealing ,Life cycle costing ,Adaptive simulated annealing ,Average cost ,Parametric statistics - Abstract
Parametric is the most often used method for Life-Cycle Cost Estimation(LCCE), of which the Parameter Selection Problem(PSP) plays a key role in modeling Cost Estimation Relationships(CERs). It is generally computational infeasible to find out the optimal solution by comparing all the combinations of parameters when the problem is large-sized. Expertise was always counted on in the past. In this paper, we employ the modern meta-heuristic algorithm, i.e., an improved Simulated Annealing algorithm, to solve the problem of large-scale. We also present a mathematic optimization model for the PSP aiming at minimizing the average cost prediction error. A case study is given to show the principle of the proposed model and simulation experiments are carried out to demonstrate effectiveness and efficiency of this algorithm. The results show that this algorithm has a high probability in finding the optimal solution just by searching very small portion of solution space, which is satisfying.
- Published
- 2010
45. A Single Item Lot Sizing Problem Considering Capital Flow and Trade Credit
- Author
-
Zhen, Chen, primary and Renqian, Zhang, additional
- Published
- 2015
- Full Text
- View/download PDF
46. A DSS based on Entropy Method in EIS in Chinese Financial Sectors
- Author
-
Renqian Zhang and Hongxun Jiang
- Subjects
Operations research ,Entropy model ,Computer science ,Loan ,Decision theory ,Entropy (information theory) ,Enterprise information system ,Core-Plus Mathematics Project ,Data science ,Credit risk ,Plural - Abstract
At the time of commercial banks verifying and assessing the loan applications of enterprises, there is one important problem faced that is how to choose the qualified ones from the numerous applications, which could be named of the Decision-making Program of Loan-granting (DPL). The members of evaluating and granting loan group make up from different departments of banks and different specialized experts. How to synthesize suggestion of expert, draw and reflect expert panel’s result of suggestion most, it has been a focus question of the decision theory all the time. The problems of loan’s group decision were briefly introduced, and then the authors proposed an entropy-based DSS for examining and approving loan applications. The core mathematics models were emphasized which applied a combination of the multi-attribute group decision-making plural entropy model and traditional group eigenvalue method for the loan evaluation purpose. And then its function, structure modules, key technology and solution method were reviewed in detail. Finally, an example is proposed to show how the entropy method can be applied to the evaluation practice.
- Published
- 2007
47. An improved Particle Swarm Optimization algorithm and its application to a class of JSP problem
- Author
-
Kun Fan, Guo-ping Xia, and Renqian Zhang
- Subjects
Mathematical optimization ,Job shop scheduling ,Mathematical model ,Computer science ,Stochastic process ,Stochastic modelling ,Process (computing) ,Particle swarm optimization ,Binary number ,Heuristics ,Algorithm - Abstract
In this paper, we analyze the special job shop scheduling problem (JSP) of actual production system in large-scale structure workshops. With regard to this kind of JSP problem, two novel mathematical models (deterministic model and stochastic model) are proposed. In addition, particle swarm optimization (PSO) algorithm is used in the paper because of its high efficiency, and binary PSO algorithm is improved for solving this special scheduling problem, i.e. how to arrange m workers to process n jobs. The results obtained from the simulation study demonstrate that using this heuristics method to solve mathematical models can reach optimal or near-optimal solutions efficiently, and can be widely used in many actual manufactories' workshops.
- Published
- 2007
48. An Mto Planning Model Considering Timing Association Rules in Orders
- Author
-
Jing Li and Renqian Zhang
- Subjects
Production planning ,Association rule learning ,Operations research ,Order (exchange) ,Computer science ,Build to order ,Genetic algorithm ,Mode (statistics) ,State (computer science) ,Data mining ,computer.software_genre ,computer - Abstract
Due to the uncertainty of future demand, companies have changed their production planning mode from pre-planning to produce according to the accepted orders, which is named as make-to-order (MTO) or build-to-order (BTO). The hypothesis of independent demand, which falls short of the real state, has been widely introduced in the model of traditional production planning. In general, the future demand and current orders are not completely independent. This paper introduces the data mining method of timing association rules to the model of MTO production planning. Through timing association rules, the relevancy of the future demand and current orders is considered and the future order demand can be forecasted from the history order data by association rules. The heuristic algorithm based on genetic algorithm (GA) is proposed to solve the model. A numeric example is built to demonstrate the proposed model and algorithm.
- Published
- 2007
49. Non-linear optimal control of manufacturing system based on modified differential evolution
- Author
-
Jianxun Ding and Renqian Zhang
- Subjects
Nonlinear system ,Engineering ,business.industry ,Differential equation ,Production control ,Differential evolution ,Production (economics) ,ComputerApplications_COMPUTERSINOTHERSYSTEMS ,Control engineering ,Construct (python library) ,business ,Optimal control ,Manufacturing systems - Abstract
This study considers the non-linear optimal control of the complex manufacturing system. We construct a mathematical model, which decomposes the complex manufacturing system into many correlated working centers, where the number of inventory and production evolves dynamically. It aims to minimize the cost of production control. We can utilize MDE algorithm to solve this model. The model can be easily used in multi-product, multi-center, multi-period manufacturing system.
- Published
- 2006
50. Association Rules Based Research On Man-Made Mistakes In Aviation Maintenance: A Case Study
- Author
-
Jun-ling Yang and Renqian Zhang
- Subjects
Association rule learning ,Risk analysis (engineering) ,business.industry ,media_common.quotation_subject ,Aircraft maintenance ,Quality (business) ,Aerospace ,business ,Maintenance management ,Production system ,media_common - Abstract
It's an important problem for aviation maintenance enterprise to assure quality of maintenance activity. Thinking over human factors and organization management, the paper produces a production system continuous improvement model for aviation maintenance quality. First, the model gathers characteristics of human factors and man-made maintenance mistakes. Based on association rules, relationships between human factors and the man-made mistakes are found. So, measures for improving organization and management could be produced, which is more pertinent. And, these measures will be used for production system continuous improvement. In an aviation maintenance firm, we made a case study in maintenance management of a type of military aero-transporter and reach to the anticipative effects
- Published
- 2006
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