• 산업경영시스템학회지
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• 제19권39호
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• pp.275-284
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• 1996

It can be made a definition that scheduling is a imposition of machinery and equipment to perform a collection of tasks. Ultimately scheduling is an assessment of taking order for which would be perform. So it is called "sequencing" in other words. In a job shop scheduling, the main object is to making delivery in accordance with the due date and order form customer, not to producing lots of quantity with minimizing mean flow time in a given time. Actually, in a company, they concentrate more in the delivery than minimizing the mean flow time. Therefore this paper suggest a new priority dispatching rule under consideration as below in a n/m job shop scheduling problem with due date. 1. handling/transportation time, 2. the size of customer order With this algorithm, we can make a scheduling for minimizing the tardiness of delivery which satisfy a goal of production.roduction.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 1995년도 추계학술대회발표논문집; 서울대학교, 서울; 30 Sep. 1995
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• pp.347-347
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• 1995

• 한국경영과학회지
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• 제27권2호
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• pp.97-109
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• 2002

Manufacturing environments in the real world are subject to many sources of change and uncertainty, such as new job releases, job cancellations, a chance in the processing time or start time of some operation. Thus, the realistic scheduling method should Properly reflect these dynamic environment. Based on the release times of jobs, JSSP (Job Shoe Scheduling Problem) can be classified as static and dynamic scheduling problem. In this research, we mainly consider the dynamic JSSP with continually arriving jobs. The goal of this research is to develop an efficient scheduling method based on GA (Genetic Algorithm) to address dynamic JSSP. we designed scheduling method based on SGA (Sing1e Genetic Algorithm) and PGA (Parallel Genetic Algorithm) The scheduling method based on GA is extended to address dynamic JSSP. Then, This algorithms are tested for scheduling and rescheduling in dynamic JSSP. The results is compared with dispatching rule. In comparison to dispatching rule, the GA approach produces better scheduling performance.

• 자연과학논문집
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• 제9권1호
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• pp.145-152
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• 1997

백화점에서 의복을 판매하고 있는 샵마스터와 판매원들의 인구통계적 특성과 역할의 차이, 직업만족도, 교육의 필요성에 대해 연구하였다. 샵마스터가 판매원보다 연령, 판매경력, 그리고 월수입에서 높은 것으로 나타났으며, 직무상의 차이점에서는 전문적인 역할 분담은 없고, 샵마스터가 매장 디스플레이, 의류교체 제안 및 의류주문, 전반적인 매장관리의 역할을 더 많이 수행하는 것으로 나타났다. 직업에 대한 보람과 긍지 면에서는 샵마스터가 판매원보다 높았으며, 교육에 대한 필요성은 모두 높은 수치를 나타냈다.

• 대한산업공학회지
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• 제19권2호
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• pp.23-34
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• 1993

Although there are numerous studies that address the problem of optimal machine grouping and part family classification for cellular manufacturing, little research has been reported that studies the conditions where cellular manufacturing is appropriate. This paper, in order to evaluate and compare the job shop with the GT cellular shop, the performance of those shops were simulated by using SIMAN. We tested the effect of independent variables including changes of product demands, intercell flow level, group setup time, processing time variability, variety of material handling systems, and job properties (ratio of processing time and material handling time). And also performance measures (dependent variables), such as machine utilization, mean flow time, average waiting time, and throughput rate, are discussed. Job shop model and GT cellular shop written in SIMAN simulation language were used in this study. These systems have sixteen machines which are aggregated as five machine stations using the macro feature of SIMAN. The results of this research help to better understand the effect of production factors on the performance of cellular manufacturing systems and to identify some of the necessary conditions required to make these systems perform better than traditional job shops. Therefore, this research represents one more step towards the characterization of shops which may benefit from cellular manufacturing.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2002년도 춘계학술대회 논문집
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• pp.429-434
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• 2002

For companies assembling end products from sub assemblies or components, MRP (Material Requirement Planning) logic is frequently used to synchronize and pace the production activities for the required parts. However, in MRP, the planning of operational-level activities is left to short term scheduling. So, we need a good scheduling algorithm to generate feasible schedules taking into account shop floor characteristics and multi-level job structures used in MRP. In this paper, we present a GA (Genetic Algorithm) solution for this complex scheduling problem based on a new gene to reflect the machine assignment, operation sequences and the levels of the operations relative to final operation. The relative operation level is the control parameter that paces the completion timing of the components belonging to the same branch in the multi-level job hierarchy. In order to revise the fixed relative level which solutions are confined to, we apply large step transition in the first step and GA in the second step. We compare the genetic algorithm and 2-phase optimization with several dispatching rules in terms of tardiness for about forty modified standard job-shop problem instances.

• Management Science and Financial Engineering
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• 제20권2호
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• pp.33-37
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• 2014

A flow shop scheduling problem involves scheduling jobs on multiple machines in series in order to optimize a given criterion. The flow time of a job is the amount of time the job spent before its completion and the stretch of the job is the ratio of its flow time to its processing time. In this paper, a hybrid genetic algorithm (HGA) approach is proposed for minimizing the total stretch in flow shop scheduling. HGA adopts the idea of seed selection and development in order to reduce the chance of premature convergence that may cause the loss of search power. The performance of HGA is compared with that of genetic algorithms (GAs).

• International Journal of Precision Engineering and Manufacturing
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• 제1권2호
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• pp.124-131
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• 2000

A shop floor can be considered as and importand level to develop a Computer Integrated Manufacturing system (CIMs). The shop foor is a dynamic environment where unexpected events contrinuously occur, and impose changes to planned activities. The shop floor should adopt an appropriate control system that is responsible for scheduling coordination and moving the manufacturing material and information flow. In this paper, the architecture of the hybrid control model identifies three levels; i.e., the shop floor controller (SFC), the cell controller(CC) and the equipment controller (EC). The methodology for developing these controller is employ an object-oriented approach for static models and IDEF0 for function models for dispatching a job. SFC and CC are coordinated by employing a multi-factors bidding and an adapted Analytic Hierarchy Process(AHP) prove applicability of the suggested method. Test experiment has been conducted by with the shopfloor, consisting of six manufacturing cells.

• 산업공학
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• 제12권2호
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• pp.329-336
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• 1999

Job efficiency and productivity of a manufacturing system with frequent job schedule changes are affected by performance of information system between job order planners anti manufacturing device operators. This paper describes implementation of concurrent information system which can active identify machine status and dispatch job orders to operators in a machine shop. Client and server environment for various machinery is implemented using OSI based network between shop floor control system and manufacturing devices. Portability and scalability are among many characteristics of the implemented system. The developed client and server system is expected to realize high productivity for manufacturing device.

• 복식문화연구
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• 제14권5호
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• pp.715-727
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• 2006

The purposes of this study are to investigate the job satisfaction, customer satisfaction and revisiting intention to beauty shops, and to examine the difference of the job satisfaction, customer satisfaction, and revisiting intention between franchised and non-franchised beauty shops. Data were obtained via questionnaire, which developed by results of pretest and previous studies, from workers and consumers of beauty shops in Busan. They were analyzed by factor analysis, t-test and regression. The results were as follows; First, the job satisfaction of beauty shops workers was composed of Adaptation, Operation and Instruction. For both of franchised and non-franchised beauty shops, the operation of beauty shops greaty influenced the job satisfaction of workers, and job satisfaction is not significantly different. Second, consumer satisfaction related to services of beauty shops is composed of three factors: Policy, Personal service, and Physical environment. Regardless of shop types, the policy of shop influenced the consumer satisfaction. Consumers' revisiting intentions to beauty shops are influenced by consumer satisfaction. Third, consumers in franchised beauty shops is less likely to be satisfied and to have the intentions to revisit than those of non-franchised beauty shops. Resulted provide some insights to develop strategies for franchised and non-franchised beauty shops. Limitations and future research directions have been discussed.