• Journal of the Korean Society for Precision Engineering
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• 제20권2호
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• pp.50-57
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• 2003

This paper presents the experimental results to verify the atomization characteristics and environmental impact of cutting fluid. Even though cutting fluid improves the productivity through the cooling, Lubricating effects, environmental impact due to cutting fluid usage is also increased on factory shop floor Cutting fluid's aerosol via atomization process can be affected human health risk such as lung cancer and skin diseases. Experimental results show that the generated fine aerosol which particle size less than 10 micron appears near working tone under typical operational conditions. The aerosol concentration also exceeds NIOSH regulations. This research can be provided a basis of environmental impact analysis fur environmental consciousness.

• Transactions of the Korean Society of Machine Tool Engineers
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• 제13권2호
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• pp.1-8
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• 2004

Applications of the deep hole drilling process can be found in many industries ranging from large aerospace manufacturer to small tool and die shop. Deep hole drilling process with small diameter generally requires high quality and accuracy. But problems which may arise or result from the deep hole drilling process include drill breakage, the generation of a finished part surface which does not satisfy required quality, and process instability. To guaranty the required machining quality and accuracy, it is important to understand and improve the deep hole drilling process. In this study, deep hole drilling experiments using tingle edge drill with small diameter under 2mm have been carried out for difficult to cut materials such as C42CrMo4 and C45pb and the experimental results were analyzed. Feed force and torque versus feed showed linear relationship in both materials. The feed force and torque are decreased as cutting speed is increased but the trends are not uniform in C42CrMo4.

• Journal of Fashion Business
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• 제11권6호
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• pp.75-86
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• 2007

This study investigated the differences of consumers' perception toward immoral shopping behavior when they shop in apparel retail stores by consumer characteristics such as ethical ideology and gender. Forsyth's(1980) ethical ideology measuring idealism and relativism was used. Three hundred twenty-five college students enrolled at a large university located in a metropolitan area participated in the study. These students were divided into four groups on the basis of their ethical ideology: situationist, subjectivist, exceptionist, or absolutist. A series of factor analyses revealed three factors of immoral shopping behaviors: shoplifting, active immoral shopping behaviors, and passive immoral shopping behaviors. The four groups significantly differed in regard to their perceptions toward active immoral shopping behaviors and passive immoral shopping behaviors. T-tests revealed that females tended to perceive shoplifting and passive immoral shopping behavior factor worse than males. The results of this study would be used for developing consumer educational programs and retail training programs.

• Proceedings of the Korea Society for Simulation Conference
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• 한국시뮬레이션학회 1993년도 제3회 정기총회 및 추계학술발표회
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• pp.16-16
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• 1993

The efficient use of capital intensive FMS requires determination of effective dispatching priority with which the parts of the selected part types are to be inputed into the system. This paper presents a simulation-optimization approach to find an appropriate dispatching priority. The study is based on a detailed simulator for a module-type commercial FMS, Specifically, after presenting the basic configuration and fundamental control logic of the system together with its main characteristics as a special type of a job shop, an algorithm is presented which combines simulated annealing and simulation to explore a dispatching priority of operations that minimizes the total tardiness, Computational performance of the algorithm shows that good solutions can be obtained within a reasonable amount of computations. The paper also compares the performance of the "optimal" or near optimal dispatching priority generated by the proposed algorithm with those generated by standard dispatching rules such as SPT, EDD and SLACK.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 한국해양공학회 2004년도 학술대회지
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• pp.283-287
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• 2004

Arc welding is sometimes used to repair damaged cast iron parts in diesel engine for driving a ship. In this case cola arc welding. is good for. saving the time and results in good repairing. But if some difference in hardness on welding zones made with AWS E Ni-CI and NiFe-CI. happen, repaired parts would be cracked in a short. In order to overcome this default, the study is performed on varying preheating temperature of welding parts, selecting welding rod and welding work way. The result will be used on ship's repair working shop.

• Journal of Ocean Engineering and Technology
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• 제20권2호
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• pp.41-45
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• 2006

Arc welding is sometimes used to repair damaged cast iron parts in diesel engine for driving n ship. In this case cold arc welding is good for saving the time and results in good repairing. But if some difference in hardness on welding zones made with AWS E Ni-CI and NiFe-CI happen, repaired parts would be cracked in a short. In order to overcome this default, the study is performed on varying preheating temperature of welding parts, selecting welding rod and welding work way. The result will be used on ship's working shop.

• Journal of Korean Institute of Industrial Engineers
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• 제23권2호
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• pp.403-420
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• 1997

In this paper, we examine the effect of production uncertainty to production control policies. First, we examine two famous production control policies, namely, MRP and JIT from the view point of shop floor control perspective, and analyze the differences between them due to demand fluctuations and activity time variations. Second, we conduct simulation studies on MRP and JIT to draw out the effects of demand fluctuations and activity time variations. Demand fluctuations are further classified into demand lumpiness and demand irregularity. And, activity time variations are further classified into stationary time variations and non-stationary time variations. Experimental results show that, in terms of demand fluctuations, MRP is affected by demand lumpiness, but JIT by demand irregularity. And we also see that both MRP and JIT are influenced by stationary time variation with respect to activity time variations.

• IE interfaces
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• 제8권2호
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• pp.135-150
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• 1995

An object-oriented simulation modeling environment, AgvTalk, is presented to provide flexible modeling capabilities for simulation of many alternative AGV systems. The hierarchical features and modularity of AgvTalk create possibilities for the extension and reuse of simulation object components. Also, detailed behavior of each object in the AGV system can be modeled easily and exactly in AgvTalk because there are no limiting modeling constructs. The modeling capabilities of AgvTalk is demonstrated by designing and simulating a conceptually different configuration of AGV systems, known as, the tandem configuration. Between the tandem and conventional AGV systems, the characteristics and design methodology in AgvTalk are described. Also, simulations between two systems are compared with AgvTalk in the job shop environment.

• Journal of Intelligence and Information Systems
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• 제1권2호
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• pp.123-137
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• 1995

Most of solution methods in scheduling attempt to generate good solutions by either developing algorithms or heuristic rules. However, scheduling problems in the real world require considering more factors such as multiple objectives, different combinations of heuristic rules due to problem characteristics. In this respect, the traditional mathematical a, pp.oach showed limited performance so that new a, pp.oaches need to be developed. Expert system is one of them. When an expert system is developed for scheduling one of the most difficult processes faced could be knowledge acquisition on scheduling heuristics. In this paper we propose a method for the acquisition of knowledge on the selection of scheduling heuristics using Dempster-Shafer Theory(DST). We also show the examples in the multi-objectives environment.

• Fashion & Textile Research Journal
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• 제11권1호
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• pp.66-74
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• 2009

The purpose of this study is to identify the factors mainly recognized by customers regarding environmental elements of clothing store. The respondents are classified into several groups according to their preferences on the environmental elements of clothing store. Also the relationship between the factors and the shopping characteristics of customers is reviewed based on the results. This survey was carried out through a questionnaire of male and female university students(Busan region) in their twenties. The data were analyzed by using Factor analysis, Cluster analysis, one-way ANOVA, Duncan test as a post identification and regression analysis. The results of this research can be summarized as follows; The perceived 7 factors about environmental elements of clothing store were service policy, store atmosphere, product variety, shopping convenience, trend of products, freedom of shopping and reception service. The respondents were classified into three groups(high recognizing group, middle recognizing group and low recognizing group) by the level of recognizing 7 factors. There were significant differences among 3 groups divided by the degree of recognizing the factors regarding environmental elements of clothing store and there was the meaningful relationship between these 7 factors and shopping characteristics. The high recognizing group has shopping characteristics like more shopping time, large expenditure for clothing and a lot of comparative stores. They are frequently in contact with clothing shopping environment and easily purchase clothes. Finally, the factors perceived by the environmental elements of clothing store significantly affected the shopping characteristics of the customers. So, store managers have to look for the perceived environmental elements of store by business and seek after the marketing factors which efficiently stimulate consumer.