• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1360-1363
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• 1996

EPD(End Point Detection) is used to decide etching degree of layer which must be removed at wafer etching process in plasma etching process which is one of the most important process in semiconductor manufacturing. In this thesis, the method which detects malfunction of etching process in real-time will be discussed. Several EPD signal traces are collected in normal plasma etching condition and used as reference EPD signal traces. Critical points can be detected by applying differentiation and zero-crossing techniques to reference EPD signal. Mean and standard deviation of critical parameters which is memorized from reference EPD signal are calculated and these determine the lower and higher limit of control chart. And by applying statical control chart to EPD signals which are collected in real etching process malfunctions of process are detected in real-time. By means of applying this method to the real etching process we prove our method can accurately detect the malfunction of etching process and can compensate disadvantage of current industrial method.

• 한국조경학회지
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• 제27권3호
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• pp.80-87
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• 1999

This paper examines the conventional notion of natural beauty and its legacy on the aesthetic experience of nature and landscape architecture in terms of critical perspective. We can take its clue for discussion from the our routine convention of experiencing natural beauty from the picture-like nature. We often equate natural beauty with superficial representations of nature shown in pictures. However, it is no more than a by-stander's nature seen purely through the eyes of the outsider. Problems of the picture-like nature can be summarized as the contemplative and visual-oriented aesthetic experience of landscape, which has had its influence not only on the ways of seeing the natural beauty but also on the ways of making it. The tradition of the picture-like nature has been transplanted into the real world through the practice of landscape architecture. It has been mass-producing superficial beauty of nature, focused on visual form. Landscape architecture in such a form is just a static means of decoration devoid of meaning and content.

• 열병합발전
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• 통권36호
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• pp.16-21
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• 2003

For many years, T/G Supplier has constructed a number of thermal power plants and researched to improve the performance and the reliability of steam turbine, which are achieved by advances in design and materials technology. In recent, interest is renewed in advance steam condition as means of improving economy of thermal power plant and reducing environmental pollution. Improvements in the maximum power have been driven by the development of advanced rotor and bucket material and longer last stage bucket. Improvements in efficiency have been brought through advance in mechanical efficiency and thermodynamic efficiency. This paper describes a number of new steam path design features introduced to the steam turbine product. And also this paper describes new design technologies' development, new technologies' trend and technologies' development for ultra-super critical steam turbine.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.2174-2179
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• 2003

For many years, T/G Supplier has constructed a number of thermal power plants and researched to improve the performance and the reliability of steam turbine, which are achieved by advances in design and materials technology. In recent, interest is renewed in advanced steam condition as means of improving economy of thermal power plant and reducing environmental pollution. Improvements in the maximum power have been driven by the development of advanced rotor and bucket material and longer last stage bucket. Improvements in efficiency have been brought through advances in mechanical efficiency and thermodynamic efficiency. This paper describes a number of new steam path design features introduced to the steam turbine product. And also this paper describes new design technologies' development, new technologies' trend and technologies' development for ultra-super critical steam turbine.

• 태양에너지
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• 제9권2호
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• pp.58-68
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• 1989

This paper describes an experimental study that was performed to determine the limiting factors on the power output in the closed cycle Electro-Hydro-Dynamic generator of small capacity. A corona discharge for producing unipolar charged particles used as the charging method. The experiment demonstrated that the corona method of charging was an efficient and effective means of producing unipolar charged particles. Four factors having an effect on the power output characteristics of EHD generator are discussed and examined experimentally, using methyl alcohol and kerosene as working fluides; a. The conversion length between attractor and collector. b. The corona current of Emitter. c. The flow velocity of working fluids. d. Load resistance. This results are as follows; 1) There in a critical value in conversion length for its maximum power output. 2) Power output increases almost linearly with corona current and flow velocity. 3) There is the critical value of load resistance producing a maximum power output. 4) Kerosene is known better working fluid than Methyl alcohol in this EHD generator.

• 한국철도학회논문집
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• 제9권5호
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• pp.601-605
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• 2006

Reliability of the Railway signaling system which is safety critical is determined by reliability of hardware and software. Reliability of hardware is easily predicted and demonstrated through lots of different studies and environmental tests, while that of software is estimated by the iterative test outcomes so estimates of reliability will depend on the inputs. Combinations of inputs to and outputs from the software may be mostly combinatoric and therefore all the combinations could not be tested. As a result, it has been more important to calculate reliability by means of a simpler method. This paper identifies the reliability prediction equation applicable to reliability prediction for railway signaling system software, and performs the simulation of onboard equipment of automatic train control for high speed train to review reliability prediction and validity.

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 2000년도 제17회 하계학술발표회 논문집
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• pp.175-209
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• 2000

The performance of US economy in the last cecade is considered to be driven by the IT investment. However, the causal relationship has not been conclsive between IT investment and economic performance, which makes a decision in IT investment tricky. IT as a growth strategy is critical to the developing countries which experienced resource constraint. In case IT acts as a driving force in the new technology paradigm, the less investment in IT will continue to which the growth gap between countries. When IT dose not make a significant contribution to growth, heavy investment in IT means misallocations of resources. Therfore a decision on IT investment has critical implication in terms of growth strategy. Based on a growth accounting nethod, the current study is to analyse the contribution of IT

• 한국전자거래학회:학술대회논문집
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• 한국전자거래학회 2004년도 e-Biz World Conference
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• pp.75-82
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• 2004

Recently introduced by the major credit card associations as replacements for the decommissioned SET and 3DSET protocols, the new payment models, 3DSecure and UCAF/SPA, have been designed to provide online merchants with a solution to an existing problem in online credit card transactions - the lack of an effective and efficient means of authenticating cardholders. The expected benefits arising from this added level of security from the merchant′s perspective are increased consumer confidence, significant reduction in the levels of fraud and charge backs and "liability shift". Using data gleaned from preliminary interviews, discussion forums and promotional material, we present a critical analysis of the potential barriers and facilitators that will impact on the widespread traction of these programs in the marketplace in the coming years.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1996년도 재료학회 추계학술발표회
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• pp.171-173
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• 1996

Ag coating on the textured YBCO was prepared by means of a Ag$_2$O brushed coating method. The contact between Ag coating and textured YBCO was examined by sharp knife cut and by the observation of SEM. The critical current densities of different textured YBCO samples, which included YBCO with and without Ag coating, and YBCO with Ag coating after hot moist text, were compared. The Ag coating does not influence the oxygen absorption of textured YBCO, but Ag coating can protect YBCO well from moisture and $CO_2$

• 응용통계연구
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• 제3권1호
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• pp.89-103
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• 1990

관측치가 불균형을 이룰 때, Nelson(1988)에 의한 균형 관측치에 관한 이론이 확장될 수 있음을 보여 주고 있다. 이 방법을 이용하여 이원 요인 계획법에서의 교호작용항에 대한 통계량을 구하고, 그래프를 이용한 방법을 제시 하였다.