• 유체기계공업학회:학술대회논문집
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• 2001.11a
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• pp.120-125
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• 2001

The effects of various vaned diffuser configurations, such as throat area ratios and rectangular and conical cross-section shapes. to the performance of a small-size turbo-compressor are studied. Numerical analyses were carried out for the region of diffuser and casing only. The pressure recovery coefficient was calculated to estimate the performance of the diffuser, and then compared with the measured data. Results show that the shapes and the throat area ratios of the diffuser strongly influence on the performance of a turbo-compressor.

• Journal of Power System Engineering
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• v.20 no.6
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• pp.64-70
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• 2016

The unsteady-state, incompressible and three-dimensional large-eddy simulation(LES) was carried out to evaluate the vorticity distribution of a small-size axial fan(SSAF). The X-component vorticity profiles developed around blade tips turn from axial to radial, and diminish the density of distribution according to the increase of static pressure. Otherwise, the Z-component vorticity profiles evenly develop at the region larger than the half radial distance of blade at the operating points of A and B, partly at the trailing-edge region of blade and radially over bellmouth according to the increase of static pressure.

• Journal of Power System Engineering
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• v.21 no.2
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• pp.57-63
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• 2017

The large-eddy simulation(LES) was carried out to evaluate the drag and static pressure acting on the blade surface of a small-size axial fan(SSAF) under the condition of unsteady-state, incompressible fluid and three-dimensional coordination. The axial component of drag coefficient increases with the increase of operating load, but the radial components have negligible sizes regardless of operating loads. Otherwise, the static pressures acting on the blade surfaces of SSAF show different distributions around the operating point of D equivalent to the stall. Also, with the increase of operating load, the static pressures acting on the pressure and suction surfaces of blade concentrate at the tips and leading-edges as a whole.

• 한국HCI학회:학술대회논문집
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• 2006.02b
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• pp.627-632
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• 2006

최근 들어 인간과 컴퓨터 상호작용 분야에서 기존의 인지적인 측면 이외에 정서의 역할에 대한 관심이 증폭되고 있는 추세이다. 본 연구에서는 사용자가 좁은 화면을 통해 정보검색을 수행 할 때 정서 상태에 따라 정보 검색 패턴이 다른지 알아보고자 하였다. 실험참가자들의 정서 상태를 인위적으로 유도하기 위해 검색과제를 수행하기 전에 긍정적인 정서와 부정적인 정서를 유발시킬 수 있는 음악을 듣게 하였고 동시에 자신의 과거 기역으로부터 긍정적인 정서 혹은 부정적인 정서를 유발 시킬 수 있는 과제를 수행하도록 하였다. 정서 유발 과정이 끝난 뒤 각 실험 참가자들은 좁은 화면을 통해 정보 탐색 과제를 수행하였다. 정보 탐색 과제는 주어진 시간 동안 제시되는 나라들에 대한 여행 정보를 검색하는 것이었고 정보 검색이 이루어지는 동안 소요된 시간 및 검색 페이지 링크가 기록되었다. 실험결과 긍정적인 정서상태에서는 중립 상태와 부정적인 정서 상태에 비해서 보다 광범위하고 빠른 정보검색이 이루어지는 것으로 나타났다.

• Journal of Korean Society for Quality Management
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• v.25 no.4
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• pp.1-15
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• 1997

We performed the two analyses of variance to determine the total quality management practices in the environmental pollution prevention industry by classifying the companies based on the size (large or medium/small) and on the type (manufacturing or service). A few previous studies reveal that in Korea the large companies are not the same as the medium/small companies in the TQM practices while the practices are not alterated by the type of companies whether manufacturing or service. But in the United States the TQM practices are not affected by the size of the company. Su, pp.rting the previous studies on the Korean industry our studies show that the TQM practices are significantly influenced by the company size, but not by the type of the company. Taking the results of our studies into consideration we would also like to propose a revision of examination criteria for National Quality Management Award with special emphasis given to medium/small companies.

• Journal of Korean Society for Quality Management
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• v.40 no.2
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• pp.166-175
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• 2012

Enterprises are continuously trying management innovation activities for survival. Among representative management innovation activities in domestic manufacture enterprise, which are TPS, 6 sigma, Lean 6 sigma etc. Many enterprises through these reform activity have gotten good result. However, these techniques have merits and demerits according to circumstance of enterprise. Specially, there are a lot of difficulties in medium and small size enterprises. In this research, We introduce Lean-SMAIS Method for medium and small size enterprises that is consists of the merit of lean 6 sigma and software(which is called ProEye). We prove Lean-SMAIS method is useful by applying medium and small size enterprise A company.

• Journal of Information Technology Applications and Management
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• v.14 no.4
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• pp.31-41
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• 2007

In order to keep global competitiveness, most of small and medium size manufacturing companies require to equip a product information management system which collects and analyzes the data generated at the manufacturing lines and then provides information for manager or worker to make a decision. However, these companies have a cost problem for adopting the enterprise resource planning system mostly used in large companies. To overcome this problem, we suggest an IOCP-based server for the product information management system suitable for small and medium size manufacturing companies. The basic concept of suggested server is that it is possible to process concurrently the connection requests coming from data collector and client by using the facility of asynchronous notification of OS and protect a server against overload by using the thread pool.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2668-2670
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• 2002

The generators of a small size below 100Kw are often used as power suppliers for emergency only in most domestic telecommunication companies. Serious twisted waves occur due to the inflow of harmonies from the generator into a S-type rectifier. And the increasing by stages of load upon the rectifier end up a stoppage of power supply during the serious hunting, which makes it difficult to supply power securely on the other part as well as that of communications. In case of long time of power failure the generators of a small size will be essential because the battery for emergency has a limit in capacity. Therefore it is necessary to solve the problems concerning the generators. This study is focused on the identifying and solving the problem including use of SCR elements connected to the generators.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.22 no.50
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• pp.303-311
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• 1999

The cooperation between industry and universities has actively been established for technical development using available manpower and facilities. However, it is necessary under International Monetary Fund era that cooperation among industry, universities, and government should be accomplished to increase export for small and medium size industry. In this paper, we regard the cooperation system among three independent organizations and pursue to improve the quality and productivity of the system. We propose some suggestions to grow the small and medium size industry toward export and introduce a case study.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1999.05a
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• pp.669-672
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• 1999

In this paper, we studied the properties of small-size disk-type ultrasonic motor using travelling wave for the application to the precise control robotic joint motor and fabricated it. The diameter of the ultrasonic motor fabricated was 13mm. Also, the piezoelectric vibrator was constructed by piezoelectric ceramic and elastic material. The piezoelectric ceramic was composed to PZ-PT-PMN which was shown the high electromechanical stability under high vibration level and stainless steel was used as the elastic material in which configuration was disk-type. To conform the capability of application to robotic motor, we measured the change of rotational speed according to applied voltage and applied frequency. As the results, the small-size disk-type ultrasonic motor was able to fabricate, and the revolution speed was 350 (rpm) when input voltage was 55 (Vrms) and applied frequency 160.4 IkHz] under pre-load.