| 1. |
- Liu, Shudong, et al.
(författare)
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An Efficient Inventory Rationing Strategy for Systems with Two Demand Classes and Backordering
- 2015
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Ingår i: International Journal of Production Research. - : Informa UK Limited. - 0020-7543 .- 1366-588X. ; 53:20, s. 6136-6142
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Tidskriftsartikel (refereegranskat)abstract
- For systems with two customer classes and backordering, the formulae for the optimal dynamic critical levels in the literature are too complex to be extended to large values of critical levels. In this paper, an efficient method is introduced to obtain approximate closed-form expressions for the dynamic critical levels, even for large values. It is further verified by numerical results the accuracy of the approximate expressions, from which important managerial insights can be obtained.
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| 2. |
- Liu, Shudong, et al.
(författare)
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Multi-class dynamic inventory rationing with stochastic demands and backordering
- 2015
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Ingår i: European Journal of Operational Research. - : Elsevier BV. - 0377-2217 .- 1872-6860. ; 244:1, s. 153-163
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Tidskriftsartikel (refereegranskat)abstract
- Dynamic inventory rationing is considered for systems with multiple demand classes, stationary stochastic demands, and backordering. In the literature, dynamic programming has been often applied to address this type of problems. However, due to the curse of dimensionality, computation is a critical challenge for dynamic programming. In this paper, an innovative two-step approach is proposed based on an idea similar to the certainty equivalence principle. First the deterministic inventory rationing problem is studied, where the future demands are set to be the expectation of the stochastic demand processes. The important properties obtained from solving the problem with the KKT conditions are then used to develop effective dynamic rationing policies for stochastic demands, which gives closed-form expressions for dynamic rationing thresholds. These expressions are easy to calculate and are applicable to any number of demand classes. Numerical results show that the expressions are close to and provide a lower bound for the optimal dynamic thresholds. They also shed light on important managerial insights, for example, the relation between different parameters and the rationing thresholds.
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| 3. |
- Liu, Yaqiong, et al.
(författare)
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An Auction-Based Approach for Multi-Agent Uniform Parallel Machine Scheduling with Dynamic Jobs Arrival
- 2024
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Ingår i: Engineering. - : Elsevier BV. - 2095-8099. ; 35, s. 32-45
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Tidskriftsartikel (refereegranskat)abstract
- This paper addresses a multi-agent scheduling problem with uniform parallel machines owned by a resource agent and competing jobs with dynamic arrival times that belong to different consumer agents. All agents are self-interested and rational with the aim of maximizing their own objectives, resulting in intense resource competition among consumer agents and strategic behaviors of unwillingness to disclose private information. Within the context, a centralized scheduling approach is unfeasible, and a decentralized approach is considered to deal with the targeted problem. This study aims to generate a stable and collaborative solution with high social welfare while simultaneously accommodating consumer agents' preferences under incomplete information. For this purpose, a dynamic iterative auction-based approach based on a decentralized decision-making procedure is developed. In the proposed approach, a dynamic auction procedure is established for dynamic jobs participating in a realtime auction, and a straightforward and easy-to-implement bidding strategy without price is presented to reduce the complexity of bid determination. In addition, an adaptive Hungarian algorithm is applied to solve the winner determination problem efficiently. A theoretical analysis is conducted to prove that the proposed approach is individually rational and that the myopic bidding strategy is a weakly dominant strategy for consumer agents submitting bids. Extensive computational experiments demonstrate that the developed approach achieves high-quality solutions and exhibits considerable stability on largescale problems with numerous consumer agents and jobs. A further multi-agent scheduling problem considering multiple resource agents will be studied in future work.
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| 4. |
- Si, Shubin, et al.
(författare)
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Benchmarking and developing the operational competitiveness of Chinese state-owned manufacturing enterprises in a global context
- 2010
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Ingår i: International Journal of Innovation and Learning. - : InderScience Publishers. - 1471-8197 .- 1741-8089. ; 7:2, s. 202-222
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Tidskriftsartikel (refereegranskat)abstract
- The purpose of this paper is to study the operational competitiveness of Chinese State-Owned Manufacturing Enterprises (CSOMEs) by analysing the case CSOME and comparing it with other global manufacturing companies in a Global Manufacturing Strategies (GMSS) database for developing innovation and learning. Analytical models are used to analyse the operational competitiveness of the case CSOME and its subsidiaries based on the weights of the multicriteria manufacturing strategies. The operational competitiveness development of its subsidiaries are applied to predict the future operational competitiveness of the case CSOME in a global context. The results show that quality is the most important competitive priority of the case CSOME and the case CSOME have some advantages when competing in a prospector group. The ranking and stability of the operational competitiveness of the case CSOME imply that: (1) the top CSOMEs have a strong operational competitiveness in the global context; however, they have some gaps compared to the top manufacturing enterprises in the world and (2) it will take a long time for the top CSOMEs to improve their operational competitiveness because of a huge organisational structure. Copyright © 2010 Inderscience Enterprises Ltd.
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| 5. |
- Si, Shubin, et al.
(författare)
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Operational Competitiveness of Chinese State-Owned Manufacturing Enterprise in Global Context
- 2008
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Ingår i: 2008 International Seminar on Business and Information Management. - 9780769535609 - 9780769535609 ; , s. 397-400
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Konferensbidrag (refereegranskat)abstract
- The purpose of this paper is to study the operational competitiveness of Chinese state-owned manufacturing enterprises (CSOME) by analyzing the case CSOME and comparing with other global manufacturing companies in a global manufacturing strategies (GMSS) database. Analytical models are used to analyze the operational competitiveness of the case CSOME based on the weights of the multi-criteria manufacturing strategies. The results show quality is most important competitive priority of the case CSOME and the value of flexibility is very low. The ranking of operational competitiveness implies the case CSOME have some advantages competing in prospector group, however it have some gap comparing with top manufacturing companies of the world.
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| 6. |
- Zhang, Xiang, et al.
(författare)
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Graphene oxide-based polymeric membranes for broad water pollutant removal
- 2015
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Ingår i: RSC Advances. - : Royal Society of Chemistry. - 2046-2069. ; 5:122, s. 100651-100662
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Tidskriftsartikel (refereegranskat)abstract
- Graphene oxide (GO) and its derivatives display excellent removal abilities of water contaminants; however, the complex preparation process of GO-based adsorbents and difficult collection of GO sheets during the adsorption process limit their practical applications. Hence, three kinds of GO-based polymeric membranes with specific adsorption characteristics were fabricated by a facile blending method, including GO/PES membrane, reduced GO (RGO)/PES membrane, and polyethyleneimine (PEI) coated GO membrane of GO@PEI/PES membrane. The GO/PES membrane exhibited selective adsorption for cationic dyes, the RGO/PES membrane exhibited selective adsorption for endocrine disruptors, and the GO@PEI/PES membrane exhibited selective adsorption for anionic dyes. The adsorption data fitted the pseudo-second-order kinetic model and the Langmuir isotherm well, and the adsorption process was controlled by the interparticle diffusion. The thermodynamic studies indicated that the adsorption reactions were spontaneous and exothermic processes. The dynamic adsorption results indicated that the prepared membranes could be used in wastewater filtration. The study indicated that GO-based polymeric membranes with broad water pollutant removal could be fabricated by facile strategies, and the problem of difficult collection of GO sheets during and after adsorption process was solved.
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| 7. |
- Zhang, Yingfeng, et al.
(författare)
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Clustering and Genetic Algorithm Based Hybrid Flowshop Scheduling with Multiple Operations
- 2014
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Ingår i: Mathematical problems in engineering (Print). - : Hindawi Publishing Corporation. - 1024-123X .- 1563-5147. ; 2014
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Tidskriftsartikel (refereegranskat)abstract
- This research is motivated by a flowshop scheduling problem of our collaborative manufacturing company for aeronautic products. The heat-treatment stage (HTS) and precision forging stage (PFS) of the case are selected as a two-stage hybrid flowshop system. In HTS, there are four parallel machines and each machine can process a batch of jobs simultaneously. In PFS, there are two machines. Each machine can install any module of the four modules for processing the workpeices with different sizes. The problem is characterized by many constraints, such as batching operation, blocking environment, and setup time and working time limitations of modules, and so forth. In order to deal with the above special characteristics, the clustering and genetic algorithm is used to calculate the good solution for the two-stage hybrid flowshop problem. The clustering is used to group the jobs according to the processing ranges of the different modules of PFS. The genetic algorithm is used to schedule the optimal sequence of the grouped jobs for the HTS and PFS. Finally, a case study is used to demonstrate the efficiency and effectiveness of the designed genetic algorithm.
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