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New light fields based on integration theory within the Weyl ordering product of operators
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作者 张科 李兰兰 +1 位作者 郭大伟 范洪义 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第4期160-164,共5页
The development of quantum optics theory based on the method of integration within an ordered product of operators(IWOP)has greatly stimulated the study of quantum states in the light field,especially non-Gaussian sta... The development of quantum optics theory based on the method of integration within an ordered product of operators(IWOP)has greatly stimulated the study of quantum states in the light field,especially non-Gaussian states with various non-classical properties.In this paper,the two-mode squeezing operator is derived with integral theory within the Weyl ordering product of operators using a combinatorial field in which one mode is a chaotic field and the other mode is a vacuum field.The density operator of the new light field,its entanglement property and photon number distribution are analyzed.We also note that tracing a three-mode pure state can yield this new light field.These methods represent a theoretical approach to investigating new density operators of light fields. 展开更多
关键词 integration within an ordered product of operators two-mode squeezing operator Weyl ordering entanglement property
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THEORY AND APPLICATION OF FRACTIONAL STEP CHARACTERISTIC FINITE DIFFERENCE METHOD IN NUMERICAL SIMULATION OF SECOND ORDER ENHANCED OIL PRODUCTION 被引量:1
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作者 袁益让 程爱杰 +1 位作者 羊丹平 李长峰 《Acta Mathematica Scientia》 SCIE CSCD 2015年第6期1547-1565,共19页
A kind of second-order implicit fractional step characteristic finite difference method is presented in this paper for the numerically simulation coupled system of enhanced (chemical) oil production in porous media.... A kind of second-order implicit fractional step characteristic finite difference method is presented in this paper for the numerically simulation coupled system of enhanced (chemical) oil production in porous media. Some techniques, such as the calculus of variations, energy analysis method, commutativity of the products of difference operators, decomposition of high-order difference operators and the theory of a priori estimates are introduced and an optimal order error estimates in l^2 norm is derived. This method has been applied successfully to the numerical simulation of enhanced oil production in actual oilfields, and the simulation results ate quite interesting and satisfactory. 展开更多
关键词 enhanced (chemical) oil production three-dimensional porous coupled system second-order implicit characteristic fractional step differences optimal order l^2 estimate application in actual oilfields
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The Allocation of Production orders to offshore Plants in the Clothing Industry: Part 2-Prototype System Supporting Order Allocation Decisions
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作者 梁润新 梁春森 +1 位作者 张文俊 蒙嘉亮 《Journal of China Textile University(English Edition)》 EI CAS 1999年第1期81-85,共5页
This part demonstrates a prototype system which has been constructed to enable the allocation of orders of different product types to different manufacturing locations . ’ What - if’ experiments using this system sh... This part demonstrates a prototype system which has been constructed to enable the allocation of orders of different product types to different manufacturing locations . ’ What - if’ experiments using this system show that different allocation rules would provide different outcomes in terms of the number of unallocated orders. A high number of unallocated orders will have a direct Impact on workload. Further research effort is necessary to channel into the exercbe of production order allocation with particular reference to allocation rules. 展开更多
关键词 production order ALLOCATION production planning OFFSHORE sourcing.
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Stochastic Programming For Order Allocation And Production Planning
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作者 Phan Nguyen Ky Phuc 《Computer Systems Science & Engineering》 SCIE EI 2022年第1期75-85,共11页
Stochastic demand is an important factor that heavily affects production planning.It influences activities such as purchasing,manufacturing,and selling,and quick adaption is required.In production planning,for reasons... Stochastic demand is an important factor that heavily affects production planning.It influences activities such as purchasing,manufacturing,and selling,and quick adaption is required.In production planning,for reasons such as reducing costs and obtaining supplier discounts,many decisions must be made in the initial stage when demand has not been realized.The effects of non-optimal decisions will propagate to later stages,which can lead to losses due to overstocks or out-of-stocks.To find the optimal solutions for the initial and later stage regarding demand realization,this study proposes a stochastic two-stage linear program-ming model for a multi-supplier,multi-material,and multi-product purchasing and production planning process.The objective function is the expected total cost after two stages,and the results include detailed plans for purchasing and production in each demand scenario.Small-scale problems are solved through a deterministic equivalent transformation technique.To solve the problems in the large scale,an algorithm combining metaheuristic and sample average approximation is suggested.This algorithm can be implemented in parallel to utilize the power of the solver.The algorithm based on the observation that if the remaining quantity of materials and number of units of products at the end of the initial stage are given,then the problems of the first and second stages can be decomposed. 展开更多
关键词 Mixed integer programming two-stage stochastic programming production planning order allocation
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The Allocation of Production Orders to Offshore Plants in the Clothing Industry:Part1-Model Conceptualisation
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作者 梁润新 梁春森 +1 位作者 张文俊 蒙嘉亮 《Journal of China Textile University(English Edition)》 EI CAS 1998年第2期77-81,共5页
As a rough cut planning exercise,production order allo-cation for offshore manu facturing sites in the clothingindustry has received little attention as does other typesof planning like production planning.This paper ... As a rough cut planning exercise,production order allo-cation for offshore manu facturing sites in the clothingindustry has received little attention as does other typesof planning like production planning.This paper outlinesan investigation into the exercise of production order al-location in the clothing industry.We have identified thatpractitioners involving in this exercise are not unanimousin the selection of offshore sites.Part 1 presents thebackground,objectives,process and conceptual model ofproduction order allocation. 展开更多
关键词 production order ALLOCATION production plan-ning OFFSHORE sourcing.
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Material Flow Optimization for Make-to-Stock Production System
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作者 ZHANG Bi-xi, ZHAO Wei, LIAO Zhao-hui, WANG Jun (Economic Management Faculty, Guangdong University of Technology, Gua ngzhou 510090, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期232-233,共2页
Under the condition of the market competition becom in g more and more drastic, the demands of market take on some new features such as individuation, diversification, small batch, unstableness and quick delivery et c... Under the condition of the market competition becom in g more and more drastic, the demands of market take on some new features such as individuation, diversification, small batch, unstableness and quick delivery et c. The Make-to-Stock mode is usually adopted by many enterprises to improve th e balance and stableness of production process. In such enterprises, order batch , production batch and sales batch are the important factors, which affect the s atisfaction of clients, efficiency and benefit of the enterprise. It takes purch ase, production and sales into account respectively when optimizing product batc h in traditional way. However, it ignored the influences of relations between ea ch links of whole system. It is assumed that the consumption and market demand a re continuous process whereas the factual demands are batched when economic batc h is determined. So there exist some deviations between the economic batch deter mined by traditional way and that by integral optimization. Through the integral analysis of Logistics in the production system, we know that from materials are purchased, then manufactured, finally sold, the material changed in appearance and value, it still exist in different links of production system. The amount of materials occupied varies just in different status, from stock status to produc tion status, then to waiting-be-sold status, there is not any substantial chan ge in quantity until they are sold. So we must comprehensively analyze the relat ions among each link based on integral production system, to optimize the materi al batch and cut short production cycle in order to optimize the whole system. In this paper, the production system is taken as a global entity, and in which m aterials variation law and their relations of each link are analyzed; To optimiz e the whole materials flow, a new model of multi-product systems’ economic orde r batch, economic production batch and optimal sale lot multi-product syste ms’ is developed which based on the limit of capitals and stock area. 展开更多
关键词 discrete production system economic order quanti ty economic production quantity distribution batch size
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Improved Algebraic Model for Serial Production Lines with Limited Buffer Sizes
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作者 Ke Liu Zhichun Mu +2 位作者 Datai Yu Dal Koshal David Pearce(Information Engineering School,University, of Science and Technology Beijing, Beijing 100083, China) (School of Engineering, University of Brighton, Brighton Brighton BN2 4GJ UK 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1999年第2期139-143,共5页
The ordered event model is improved to describe serial production lines with limited buffer sizes. The improved model hasthe same computational burden as the original one and can be constrUcted directly according to g... The ordered event model is improved to describe serial production lines with limited buffer sizes. The improved model hasthe same computational burden as the original one and can be constrUcted directly according to given principles. Several simulationexamples are cited to verify this improved model. Extensions and open problems are also indicated. By means of this new model, serialProduotion lines with limitations of resources can be stUdied analytically. 展开更多
关键词 ordered event model serial production line buffer size PERIOD
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Ordered product expansions of operators (AB)^±m with arbitrary positive integer
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作者 徐世民 李玉山 +2 位作者 徐兴磊 王磊 王继锁 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第10期154-160,共7页
We arrange quantum mechanical operators ■ in their normally ordered product forms by using Touchard polynomials.Moreover,we derive the anti-normally ordered forms of ■ by using special functions as well as Stirling-... We arrange quantum mechanical operators ■ in their normally ordered product forms by using Touchard polynomials.Moreover,we derive the anti-normally ordered forms of ■ by using special functions as well as Stirling-like numbers together with the general mutual transformation rule between normal and anti-normal orderings of operators.Further,the Q-and P-ordered forms of(QP)±m are also obtained by using an analogy method. 展开更多
关键词 Fock space new polynomial ordered product analogy method
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Ordering Cost Depletion in Inventory Policy with Imperfect Products and Backorder Rebate
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作者 Sandeep Kumar Teekam Singh +1 位作者 Kamaleldin Abodayeh Wasfi Shatanawi 《Computers, Materials & Continua》 SCIE EI 2021年第3期2343-2357,共15页
This study presents an inventory model for imperfect products with depletion in ordering costs and constant lead time where the price discount in the backorder is permitted.The imperfect products are refused or modifi... This study presents an inventory model for imperfect products with depletion in ordering costs and constant lead time where the price discount in the backorder is permitted.The imperfect products are refused or modified or if they reached to the customer,returned and thus some extra costs are experienced.Lately some of the researchers explicitly present on the significant association between size of lot and quality imperfection.In practical situations,the unsatisfied demands increase the period of lead time and decrease the backorders.To control customers'problems and losses,the supplier provides a price discount in backorders during shortages.Also,an order’s policies may result in including some imperfect products in arrival lots.A discount on price may be offered by the supplier on the out-of-stock products to manage the backorder problems.The study aims to develop a model with imperfect products by permitting the price discount in backorders,and the cost of ordering is considered a decision variable.First,it is assumed that the demand for lead time is followed by a normal distribution and then stops it and assumed that the first two moments of demand for lead time are known.Further,the minimax distribution method is used to solve this model,and a separate algorithm is designed.In this study,two models are discussed with and without a normally distributed rate of demand.The current study verified with the help of some numerical examples over various model parameters. 展开更多
关键词 INVENTORY ordering cost imperfect product lead time BACKorder
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Ordering Strategy for Fresh Agricultural Products in External Financing Condition 被引量:1
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作者 Wenyi DU 《Asian Agricultural Research》 2014年第7期12-14,共3页
This paper firstly introduced the two stage supply chain consisting of single agricultural product producer and fund restraint retailer.Then,it analyzed the influence of bank interest rate on order quantity,wholesale ... This paper firstly introduced the two stage supply chain consisting of single agricultural product producer and fund restraint retailer.Then,it analyzed the influence of bank interest rate on order quantity,wholesale price and expected profit of retailer and producer on the condition of retailer taking external loan strategy.Studies have shown that when the bank interest rate is in(0,0.9),the order quantity of agricultural products is a decreasing function of bank interest rate; when the bank interest rate is in(0,1),wholesale price of agricultural products decreases with increase in the bank interest rate; when the bank interest rate is in(0,0.6),the expected profit of retailer is a decreasing function of bank interest rate; when the bank interest rate is in(0,1),the expected profit of producer decreases with increase in the bank interest rate.Finally,through simulation calculation examples,it verified suitability of the conclusion,in the hope of providing reference and application value for management of supply chain. 展开更多
关键词 FUND RESTRAINT EXTERNAL FINANCING FRESH agricultur
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Theory and application of numerical simulation method of capillary force enhanced oil production
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作者 Yirang YUAN Aijie CHENG +2 位作者 Danping YANG Changfeng LI Yunxin LIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2015年第3期379-400,共22页
A kind of second-order implicit upwind fractional step finite difference methods are presented for the numerical simulation of coupled systems for enhanced (chemical) oil production with capillary force in the porou... A kind of second-order implicit upwind fractional step finite difference methods are presented for the numerical simulation of coupled systems for enhanced (chemical) oil production with capillary force in the porous media. Some techniques, e.g., the calculus of variations, the energy analysis method, the commutativity of the products of difference operators, the decomposition of high-order difference operators, and the theory of a priori estimate, are introduced. An optimal order error estimate in the l2 norm is derived. The method is successfully used in the numerical simulation of the enhanced oil production in actual oilfields. The simulation results are satisfactory and interesting. 展开更多
关键词 enhanced (chemical) oil production system on consideration ference optimal order l2 capillary force second-order three-dimensional porous coupled implicit upwind fractional step difestimate application in actual oilfield
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Minimal Generalized Time-Bandwidth Product Method for Estimating the Optimum Fractional Fourier Order
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作者 Lin Tian Zhenming Peng 《Journal of Computer and Communications》 2015年第3期8-12,共5页
A minimal generalized time-bandwidth product-based coarse-to-fine strategy is proposed with one novel ideas highlighted: adopting a coarse-to-fine strategy to speed up the searching process. The simulation results on ... A minimal generalized time-bandwidth product-based coarse-to-fine strategy is proposed with one novel ideas highlighted: adopting a coarse-to-fine strategy to speed up the searching process. The simulation results on synthetic and real signals show the validity of the proposed method. 展开更多
关键词 GENERALIZED Time-Bandwidth product Coarse-to-Fine Strategy OPTIMUM FRACTIONAL FOURIER order FRACTIONAL FOURIER Transform
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Ordering and Pricing Strategies for Fresh Products with Multiple Quality Levels Considering Consumer Utility
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作者 Peiqi Ma 《American Journal of Operations Research》 2015年第3期192-198,共7页
In this paper, considering a scenario in which there are two quality levels of fresh products and introduction of consumer utility function, we studied the optimal ordering and pricing strategies under certain quantit... In this paper, considering a scenario in which there are two quality levels of fresh products and introduction of consumer utility function, we studied the optimal ordering and pricing strategies under certain quantity. Our results showed that, facing the two quality levels of fresh products, retailers would not benefit from sales of lower quality of fresh products with the deterministic demand. In the pursuit of profit maximization, the initial order quantity is smaller than the potential demand for market. 展开更多
关键词 FRESH products CONSUMER UTILITY MULTIPLE Quality Level PRICING and orderING
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REVERSE ORDER LAW FOR GROUP INVERSE OF PRODUCT OF MATRICES ON SKEW FIELDS
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作者 Liu Yu (Dept.of Math.,Hulan Teacher College,Hulan 150500,PRC)Cao Chongguang(Dept.of Math.,Heilongjiang University,Harbin 150080,PRC) 《Numerical Mathematics A Journal of Chinese Universities(English Series)》 SCIE 2000年第S1期38-39,共2页
Let K<sup>n×n</sup> be the set of all n×n matrices and K<sub>r</sub><sup>n×n</sup> the set {A∈K<sup>n×n</sup>|rankA=r} on askew field K. Zhuang [1] ... Let K<sup>n×n</sup> be the set of all n×n matrices and K<sub>r</sub><sup>n×n</sup> the set {A∈K<sup>n×n</sup>|rankA=r} on askew field K. Zhuang [1] denotes by A<sup>#</sup> the group inverse of A∈K<sup>n×n</sup> which is the solu-tion of the euqations:AXA=A, XAX=X, AX=AX. 展开更多
关键词 MATH RI RD REVERSE order LAW FOR GROUP INVERSE OF product OF MATRICES ON SKEW FIELDS OI AB
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Scheduling problem for hot-rolling seamless steel tube production 被引量:1
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作者 HUO Jiazhen~(1)),LILin~(1,2)) and LI Hu~(1)) 1) School of Economics and Management TongJi University,Shanghai 20009,China 2) School of Business,East China University of Science and Technology,Shanghai 200237,China 《Baosteel Technical Research》 CAS 2010年第S1期95-,共1页
Taking the seamless tube plant of Baoshan Iron & Steel Complex in China as the background,we analyze the characters of hot rolling seamless steel tube:multi varieties,low volume,complicated production process,flex... Taking the seamless tube plant of Baoshan Iron & Steel Complex in China as the background,we analyze the characters of hot rolling seamless steel tube:multi varieties,low volume,complicated production process,flexible production routes.Then integrated scheduling problem for hot rolling seamless steel tube production is studied,which covers two key points;order-grouping problem and solution method for flowshop/jobshop scheduling problem.On the basis of these two problems,integrated scheduling decision system is developed.The design idea,function flow sheet,data processing method,and functional module of visualized human-computer interactive scheduling system implemented in seamless steel tube plant of Shanghai Baoshan Iron & Steel Complex are described into detail.Compared with manual system,the performance of system shows the applicability and superiority in several criteria. 展开更多
关键词 hot-rolling seamless steel tube production scheduling problem order-grouping problem decision system
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Discussion on Fresh Agricultural Products Ordering and Preservation Strategy under New Normal Carbon Emission Constraint
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作者 Jianhua Zhao Ligui Chen Peixiong Zhang 《Plant Diseases and Pests》 CAS 2021年第4期33-36,共4页
The paper mainly discusses the influence of chemical,physical and biological preservation technology improvement on the preservation strategy of fresh agricultural products.Meantime,the relationship between fresh agri... The paper mainly discusses the influence of chemical,physical and biological preservation technology improvement on the preservation strategy of fresh agricultural products.Meantime,the relationship between fresh agricultural products ordering and preservation in the environment of new normal carbon emission constraint is analyzed,and the e-commerce strategy in the digital era is put forward to achieve the win-win situation of consumers,farmers and dealers,so as to achieve good ecological,economic and social benefits. 展开更多
关键词 Carbon emission constraints Fresh agricultural product ordering and preservation strategy
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Weyl-Ordered Operator Product Formula Derived by Technique of Integration Within Weyl-Ordered Product of Operators
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作者 FAN Hong-Yi GUO Qin 《Communications in Theoretical Physics》 SCIE CAS CSCD 2007年第5X期823-826,共4页
关键词 IWOP技术 程序化 数学 方程式
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装配式建筑PC构件产销一体化管理系统研究 被引量:2
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作者 陈继文 许钦圆 +1 位作者 高晓明 杨红娟 《山东建筑大学学报》 2024年第1期72-80,共9页
混凝土预制(Precast Concrete,PC)构件是装配式建筑主体结构的基础,提升其生产的智能化、信息化水平尤为关键。文章以PC构件厂的生产管理模式和普遍管理现状为研究对象,基于PC构件生产线模式的需求分析,设计管理系统的基本组成架构、静... 混凝土预制(Precast Concrete,PC)构件是装配式建筑主体结构的基础,提升其生产的智能化、信息化水平尤为关键。文章以PC构件厂的生产管理模式和普遍管理现状为研究对象,基于PC构件生产线模式的需求分析,设计管理系统的基本组成架构、静态和动态信息模块,完成管理系统的开发。通过订单跟踪和生产管理在管理系统中的集成,完成PC构件的多品种、小批量生产的一体化管理;并基于数字孪生模型与PC构件生产设备之间的信息交互,实现订单跟踪的可视化管理。结果表明:管理系统通过对PC构件的订单跟踪和质量管理,可实现订单数据的全面分析和精细化管理,并有效提升生产效率和决策管理水平。 展开更多
关键词 PC构件 生产管理 管理系统 订单跟踪 数字孪生
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基于遗传算法的划分序乘积空间问题求解层选择 被引量:1
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作者 徐怡 邱紫恒 《软件学报》 EI CSCD 北大核心 2024年第4期1945-1963,共19页
划分序乘积空间作为一种新的粒计算模型,可以从多个视角和多个层次对问题进行描述和求解.其解空间是由多个问题求解层组成的格结构,其中每个问题求解层由多个单层次视角构成.如何在划分序乘积空间中选择问题求解层是一个NP难问题.为此,... 划分序乘积空间作为一种新的粒计算模型,可以从多个视角和多个层次对问题进行描述和求解.其解空间是由多个问题求解层组成的格结构,其中每个问题求解层由多个单层次视角构成.如何在划分序乘积空间中选择问题求解层是一个NP难问题.为此,提出一种两阶段自适应遗传算法TSAGA(two stage adaptive genetic algorithm)来寻找问题求解层.首先,采用实数编码对问题求解层进行编码,然后根据问题求解层的分类精度和粒度定义适应度函数.算法第1阶段基于经典遗传算法,预选出一些优秀问题求解层作为第2阶段初始种群的一部分,从而优化解空间.算法第2阶段,提出随当前种群进化迭代次数动态变化的自适应选择算子、自适应交叉算子以及自适应大变异算子,从而在优化的解空间中进一步选择问题求解层.实验结果证明了所提方法的有效性. 展开更多
关键词 粒计算 划分序乘积空间 遗传算法 问题求解层
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考虑拆解故障的退役产品人机混流线插单调度
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作者 任莹晖 万家伟 +1 位作者 匡增彧 谢晖 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2024年第4期153-160,共8页
多源异构退役3C产品服役阶段产生的结构变形可能引发自动拆解设备故障,性能漂移失效会扰动拆解工艺规划和生产调度.以退役3C产品人机混流拆解线为研究对象,研究退役产品拆解故障导致的插单调度问题.构建量化不确定性拆解序列和拆解深度... 多源异构退役3C产品服役阶段产生的结构变形可能引发自动拆解设备故障,性能漂移失效会扰动拆解工艺规划和生产调度.以退役3C产品人机混流拆解线为研究对象,研究退役产品拆解故障导致的插单调度问题.构建量化不确定性拆解序列和拆解深度的AND/OR节点网络模型.以最大化工位利用率为优化目标,拆解故障产品缓存搬运阈值为变量,建立人机混流线插单调度模型.采用二维实数编码方式编码,选用遗传算法求解.选取58种品系退役智能手机的人机混流聚类拆解产线数据实例验证.结果表明,构建的人机混流线插单调度模型能有效制定工位利用率最大的阈值插单调度方案.实例聚类的3类混流拆解线优化后的最大工位利用率分别为80.3%、73.2%、81.3%. 展开更多
关键词 回收利用 退役产品 拆解故障 插单调度 AND/OR节点模型
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