• 산업공학
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• 제9권2호
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• pp.143-158
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• 1996

This paper deals with the development of a software module for production planning and scheduling activities of an actual die-production management system. Scheduling problems, such as master schedule and detailed schedule, are the focal point of the whole article and they are considered in terms of operation procedures. Schedule-explosion module and load levelling module are the essential components of schedule management. The scheduling module allocates the resources, determines the process priority and the planned start and completion dates of processes. Rescheduling can be done to manipulate unforeseen situations that schedule is delayed owing to inducing defectives, machine breakdowns and lumpy demands. This study indicates a practical model for the die-producation management and helps to apply it for jobs in the real situation.

• Industrial Engineering and Management Systems
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• 제10권1호
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• pp.1-6
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• 2011

This paper describes the issue of batch scheduling.In food production, the lead-time from produc-tion to sale should be decreased becausefreshness of the product is important. Products are shipped at diverse times depending on a demand of sellers, because the types of sellers has become diversified such as super-markets, convenience stores and etc. production of quantity demanded must be completed by time to ship it then. The authors consider a problem with due-dates constraints and construct the algorithm to find the opti-mal schedule that satisfy the due-dates constraint, batch size constraint, inventory time constraint and mini-mize total flow time.

• 산업공학
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• 제6권2호
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• pp.53-65
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• 1993

This paper deals with the development of a software module for production planning and scheduling activities of an existing Flexible Machining and Assembly System (FMAS). The Production Planning Module uses the hierarchical and sequential scheme based on "divide and conquer" philosophy. In this module, routes are determined based on the production order, orders are screened, tools are allocated, and order adjustments are executed according to the allocated tools. The Scheduling Module allocates the resources, determines the task priority and the start and completion times of tasks. Re-scheduling can be done to handle unforeseen situations such as lumpy demands and machine breakdowns. Since all modules are integrated with a central database and they interface independently, it is easy to append new modules or update the existing modules. The result of this study is used for operating the real FMAS consisting of a machining cell with 2 domestic NC machines and a part feeding robot, an assembly cell with a conveyor and 3 robots, an inspection cell, an AGV, an AS/RS, and a central control computer.

• 산업융합연구
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• 제1권2호
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• pp.69-79
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• 2003

In order to solve scheduling, many techniques including optimization and heuristics methods have been proposed. However, these conventional approaches are usually inadequate to obtain a satisfactory solution because of a NP-Complete which requires extensive computation effort. The aim of this paper is to develop an expert system for job shop scheduling using an AI technique. Through this system, the user can choose one of several performances. If one performance is chosen, then the system solves a scheduling in order to satisfy that performance. Then, this system decides urgent job. This system can utilize production resources efficiently and minimize work-in-process inventories and tardy jobs.

• 경영과학
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• 제31권3호
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• pp.13-26
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• 2014

This paper considers an integrated one-vendor multi-buyer production-inventory model where the vendor manufactures multiple products in lot at their associated finite production rates. In the model, it is allowed for each product to be shipped in lot to the buyers even before the whole product production is not completed yet. Each product lot is dispatched to the associated buyer in a number of shipments. The buyers consume their products at fixed rates. The objective is to the production and shipment schedules in the integrated system, which minimizes the total cost per unit time. The total cost consists of production setup cost, inventory holding cost and shipment cost. For the model, an iterative optimal solution procedure with shipment consolidation policy incorporated. It is then tested through numerical experiments to show how efficient and effective the shipment consolidation policy is.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 추계 학술논문 발표대회
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• pp.92-93
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• 2014

Green Frame is a method for Rahmen structure construction composed of composite PC members. The composite PC members of Green Frame which are based on in-situ production can reduce the construction cost and are more likely to secure quality when compared to production in factories. Previous studies developed forms for in-situ production of Green Frame composite PC members and proposed algorithms to arrange them on site. However, it requires not only their arrangement, but also calculation of an accurate production period to produce the required PC members in a limited space and supply them in a timely manner. In particular, it is necessary to clearly define the properties of detailed processes for in-situ production of PC members and to calculate the time required for respective process. To do so, this study is a basic research on calculating the time for in-situ production using a linear scheduling method.

• 산업경영시스템학회지
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• 제20권41호
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• pp.231-242
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• 1997

This paper describe an approximation method for solving the minimum makespan problem of job shop scheduling with fuzzy processing time. We consider the multi-part production scheduling problem in a job shop scheduling. The job shop scheduling problem is a complex system and a NP-hard problem. The problem is more complex if the processing time is imprecision. The Fuzzy set theory can be useful in modeling and solving scheduling problems with uncertain processing times. Lee-Li fuzzy number comparison method will be used to compare processing times that evaluated under fuzziness. This study propose heuristic algorithm solving the job shop scheduling problem under fuzzy environment. In This study the proposed algorithm is designed to treat opinions of experts, also can be used to solve a job shop environment under the existence of alternate operations. On the basis of the proposed method, an example is presented.

• 대한산업공학회지
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• 제33권2호
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• pp.166-173
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• 2007

In this paper, we propose a model-based approach to estimating production parameters of semiconductor FAB equipment. For FAB scheduling, for example, we need to know equipment's production parameters such as flow time, tact time, setup time, and down time. However, these data are not available, and they have to be estimated from material move data such as loading times and unloading times that are automatically collected in modern automated semiconductor FAB. The proposed estimation method may be regarded as a Bayes estimation method because we use additional information about the production parameters. Namely, it is assumed that the technical ranges of production parameters are known. The proposed estimation method has been applied to a LCD FAB, and found to be valid and useful.

• 한국CDE학회논문집
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• 제17권1호
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• pp.26-34
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• 2012

Assembly scheduling in shipbuilding is responsible for determine assembly process orders and departmental production schedule for the block, the basic composite unit of ships. It is necessary much more information to decide production scheduling as the characteristic of shipbuilding which has been more complex and more various and also, a lot of waste of time and of human power is generated in the course of data processing. The target shipbuilding manufacturer of this study use empirical techniques, based on the user's discretion, to compile and to apply data which are scattered in DB storages separately. Because of that reason, the user should not only be performed identification and screening operations but also modification and verification for vast amounts of data, so it is hard to keep the consistency of the data and also the operation time is not constant. Accordingly, the object in this study is by presenting an efficient DB framework to reduce wasting time and man-hour at experienced-oriented process, abate user's manual operations and support an efficient scheduling in assembly processes.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1993년도 춘계공동학술대회 발표논문 및 초록집; 계명대학교, 대구; 30 Apr.-1 May 1993
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• pp.46-46
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• 1993