• International Journal of Precision Engineering and Manufacturing
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• 제8권2호
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• pp.64-69
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• 2007

Aerostatic planar XY stages are frequently used as the main frames of precision positioning systems. The machining and assembly process of the rails and bed of the stage is one of first processes performed when the system is built. When the system is complete, the 2D position, motion, and stage flatness errors are measured in tests. If the stage errors exceed the application requirements, the stage must be remachined and the assembly process must be repeated. This is difficult and time-consuming work. In this paper, a method for estimating the errors of a planar XY stage is proposed that can be applied when the rails and bed of the stage are evaluated. Profile measurements, estimates of the motion error, and 2D position estimation models were considered. A comparison of experimental results and our estimates indicated that the estimated errors were within $1{\mu}m$ of their true values. Thus, the proposed estimation method for 2D position and flatness errors of an aerostatic planar XY stage is expected to be a useful tool during the assembly process of guideways.

• 패션비즈니스
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• 제17권1호
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• pp.145-156
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• 2013

The purpose of this study is to demonstrate the stage costumes realized by digital clothing ; how realistic and accurate representation of empirical testing and in the consultation process for the production stage costumes, determine whether digital clothing has value that can be substituted for the stage costume. This study researched the stage costume manufacture, Isabel's costume of the musical 'Christmas Carol', process by using the 3-D clothing simulation technology : DC Suite. The results of this study is as following. They share many similarities between the stage costumes and digital clothing. It is possible that digital clothing takes a role as a substitute for stage costumes in the production process of the clothing samples. The clothing production system, including stage costumes, by digital clothing costs and lead time can be saved by innovative. Also the result can be saved without restriction, and this system can exert its effect in a very efficient way to incorporation of foreign producers and production system.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 압출 및 인발 심포지엄
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• pp.20-23
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• 1999

The current three-stage cold extrusion process including upsetting to produce a flange is investigated for the purpose of improvement of manufacturing process. The main goal of this study is to obtain an appropriate process sequence which can produce the required part most economically without overloading of tools and select an appropriate process for reducing manufacturing cost. The current process sequence is simulated and design criteria are examined. Based on the results of simulation of the current three-stage process, a design strategy for improving the process sequence is developed using the thick-wall pipes. Based on the results of simulation of the one-stage processes, the forming processes of a flange for improving the conventional process are proposed.

• 상하수도학회지
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• 제30권3호
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• pp.271-278
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• 2016

Recently, reverse osmosis (RO) is the most common process for seawater desalination. A common problem in both RO and thermal processes is the high energy requirements for seawater desalination. The one energy saving method when utilizing the osmotic power is utilizing pressure retarded osmosis (PRO) process. The PRO process can be used to operate hydro turbines for electrical power production or can be used directly to supplement the energy required for RO desalination system. This study was carried out to evaluate the performance of both single-stage PRO process and two-stage PRO process using RO concentrate for a draw solution and RO permeate for a feed solution. The major results, were found that increase of the draw and feed solution flowrate lead to increase of the production of power density and water permeate. Also, comparison between CDCF and CDDF configuration showed that the CDDF was better than CDCF for stable operation of PRO process. In addition, power density of two-stage PRO was lower than the one of single-stage. However, net power of two-stage PRO was higher than the one of single-stage PRO.

• 대한가정학회지
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• 제30권1호
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• pp.199-217
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• 1992

The purpose of this study was to examine changes in the household investment planning according to the family life cycle, to improve the household investment planning process, and to develop research model. The results were as follows : Household investment planning varied with stages of the family life cycle because the stock of resources shifted and financial goals changed as the family life cycle stage changed. The main financial goals of family in each stage of the life cycle were the purchasing of house in the establishing stage, children's education and marriage in the extending stage, and the elderly's economic welfare in the diminishing stage. Also, in the Ⅰ & Ⅱ stage the most important investment goals were the purchasing of house, children's education in the Ⅲ stage, children's marriage in the Ⅳ stage, and the elderly's economic welfare in the Ⅴ stage. Therefore, the financial goals were recognized as the important goals underlain the investment-planning goals, and alternatives for the accomplishment of investment-planning goals were determined. The results of this study can contribute to establish the long-run investment planning process and improve the level of household's financial well-being.

• 기술혁신학회지
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• 제12권1호
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• pp.237-264
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• 2009

선도적으로 기술창출단계의 기술혁신에 성공하여 최초경로로 기술리더가 된 국내기업에 대한 혁신 연구는 새롭게 도전하려는 국내기업과 개발도상국기업에게 시행착오를 줄일 수 있는 시사점을 제공할 수 있다. 그러나 개발도상국기업의 기술창출단계 혁신에 대한 연구가 부족하며, 특히 프로세스혁신에 대한 연구는 제품혁신연구에 비해 더욱 부족한 상황이다. 본 연구는 기술창출단계의 프로세스 기술혁신 프로젝트를 대상으로 하는 탐색적 연구이다. 최초경로로 기술리더가 된 POSCO의 FINEX(파이넥스) 사례에서는 기술창출단계 혁신은 기술내재화단계 고도화의 연장선이라기보다는 높은 위험을 감수하는 최고경영층의 결단에 의해 시도되는 불연속적인 특성이 있으며, 기술창출단계 혁신을 시작하는 개발도상국기업이 일반적으로 초기에 직면하는 원천기술을 개발을 위한 기술역량의 부족은 원천기술을 개발 중인 선발자와의 보완적 기술협력을 통해 극복하였다. 그리고 선진국 경쟁자보다 뒤늦게 기술 개발을 시작하였지만 가장 먼저 상용화단계에 도달할 수 있었던 것은 기술개발 가속화(Speed-up)로 기술개발속도에 영향을 주는 세부요인을 파악하였다.

• Asia pacific journal of information systems
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• 제16권3호
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• pp.67-93
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• 2006

Some consumers prefer online and others prefer offline. What makes them prefer online or offline? There has been a lack of theoretical development to adequately explain consumers' channel switching behavior between traditional physical stores and new virtual stores. Through consumers' purchase decision processes, this study examined the reasons why consumers changed channels depending on purchase process stages. Consumer's purchase decision process could be divided into three stages: pre-purchase stage, purchase stage, and post-purchase stage. We used the intention of channel selection as a surrogate dependent variable of channel selection. And some constructs, that is, channel function, channel benefits, customer relationship benefits, and perceived behavioral control, were selected as independent variables. In buying look-and-feel products, it was identified that consumers preferred virtual stores to physical stores at pre-purchase stage. To put it concretely, all constructs except channel benefits were more influenced to consumers at virtual stores. This result implied that information searching function, which is a main function at pre-purchase stage, was better supported by virtual stores than physical stores. In purchase stage, consumers preferred physical stores to virtual stores. Specially, all constructs influenced much more to consumers at physical stores. This result implied that although escrow service and trusted third parties were introduced, consumers felt that financial risk, performance risk, social risk, etc. still remained highly online. Finally, consumers did not prefer any channel at post-purchase stage. But three independent variables, i.e. channel function, channel benefits, and customer relationship benefits, were significantly preferred at physical stores rather than virtual stores at post-purchase stage. So we concluded that physical stores were a little more preferred to virtual stores at post-purchase stage. Through this study, it was identified that most consumers might switch channels according to purchase process stages. So, first of all, sales representatives should decide that what benefits should be given them through virtual stores at the pre-purchase stage and through physical stores at the purchase and post-purchase stages, and then devise collaborative channel strategies.

• 산업경영시스템학회지
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• 제43권2호
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• pp.65-71
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• 2020

Worldwide plant market keeps maintaining steady growth rate and along with this trend, domestic plant market and its contractors also maintain such growing tendency. However, in spite of its external growth, win-win growth of domestic material industry that occupies the biggest share in plant industry cost portion is extremely marginal in reality. Domestic plant material suppliers are required to increase awareness of domestic material brand by securing quality and reliability of international standard through improvement of design quality superior to that of overseas material suppliers. Improvement of design quality of plant material becomes an essential element, not an option, for survival of domestic plant industry and its suppliers. Under this background, in this study, priority and importance by each evaluation index was analyzed by materializing plant design stage through survey of experts and defining evaluation index by each design stage and based on this analysis result, evaluation index of stage-gate based decision-making process that may improve design quality of plant material was suggested. It is considered that by utilizing evaluation index of stage-gate based decision-making process being suggested in this study, effective and efficient decision-making of project decision-makers would be enabled and it would be contributory to improve design quality of plant material.

• 보건교육건강증진학회지
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• 제23권1호
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• pp.63-75
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• 2006

Objective: This study was performed to identify the related factors of change affecting the stage of change, on the assumption that there are various stages of change in the exercise behavior of workers. Method: The subjects of the study consisted of 138 workers of 10 workplaces located in Daejeon City, and data collected by using questionnaires were analyzed with SPSS/WIN 11.5 program. Results: The subjects were distributed in the stage of exercise behavior change as follows: precontemplation stage(10.9%), contemplation stage(22.5%), preparation stage(41.3%), action stage(8.7%), and maintenance stage(16.7%). Of the process of change depending on the stage of exercise behavior change, the consciousness raising(F=11.50, p=.00), dramatic relief(F=2.82, p=.02) showed significant difference in the cognitive process, and the counter conditioning(F=4.56, p=.00), reinforcement management(F=4.64, p=.00), self-liberation(F=9.46, p=.00), and stimulus control(F=13.28, p=.00) showed significant difference in the behavioral process. For decision-making depending on the stage of exercise behavior change, both the pros of decision-making(F=9.23, p=.00) and the cons of decision-making(F=2.45, p=.04) showed significant difference. Self-efficacy depending on the stage of exercise behavior change showed significant difference as F=11.50, p=.00. The related factors of change affecting the stage of exercise behavior change were the pros of decision-making, the cons of decision-making, and self-efficacy including 34.1% R-square. Conclusion: In order to change the exercise behavior of workers positively, they need to be stimulated to use the cognitive and behavioral process in the process of change properly, and to be induced to make a decision positively. And also exercise programs suitable to various characteristics of each worker as well as those of workplaces to enhance self-efficacy need to be applied after being devised. Through the further longitudinal research, it is necessary to analyze the various aspects, such as groups to select, to maintain, to stop or give up the exercise, and to avoid the change, and to study how the related factors of change affect diversity like the above.

• International Journal of Precision Engineering and Manufacturing
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• 제2권2호
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• pp.57-64
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• 2001

In recent years, the concern of designing multi-stage gear drives ha increased with more application of them in high-speed and high-load. Until now, however, the researches on the design of gear drives have been focused on single gear pairs. Thus the design practice for multi-stage gear drives has been depended on experiences and expertise of designers and carried out commonly by trial and error. We propose an automation algorithm for the design of two-and three-strage cylindrical gear drives. The two types of dimensional design processes have been proposed to determine gear dimensions in a formal way. The first design process(Process I) uses to total volume of gears to determine gear ration , and uses K factor , unit load and aspect ration to determine gear dimensions, The second one(Process II) makes use of Niemann's formula and center distance to calculate gear ratio and gear dimensions. Process I and Process II employ material date from AGMA and ISO standards, respectively. The configuration design determines the positions of gears with minimizing the volume of gearbox by using a simulated annealing algorithm. The availability of the design algorithm is validated by the design examples to two-and three=stage gear drives.