• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 추계학술대회
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• pp.265-270
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• 2003

When designing an engine part the designer has to choose the proper material and to define the dimensions of the part. in the most rudimentary case he has available as guidelines the collective experience from similar applications. The performance of the part is tested on occasion of the trial runs for the full system, and possibly occurring deficiencies are corrected until a satisfactory usable life and safety of operation is achieved. This procedure is time consuming and costly, and the learning effect is minimal. These requirements have to be condensed into characteristic values ameanable to computation. Since testing and computation are complementary we have to look at the currently existing mathematical models for engine bearing performance.

• 한국철도학회논문집
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• 제8권3호
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• pp.286-292
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• 2005

In this paper, we introduce IEC 60300(Dependability program management) into urban transit system, and propose effective method to apply IEC 60300 to Subway Corporation. The dependability is the collective term used to describe the availability performance and its influencing factors such as reliability performance, maintainability performance and maintenance support performance. A dependability program covers all phases of a system's life cycle from planning to operation and possibly disposal, and is composed of program elements divided into tasks.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 추계학술대회 초록집
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• pp.36.2-36.2
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• 2011

In variable-speed variable-pitch wind turbines, the conventional approach for controlling power-production operation relies on a generator-torque controller and a rotor-collective blade-pitch controller. Both controllers use the generator speed measurement as the sole feedback input. In order to mitigate unwanted excitation of the control system, many filters are adopted. In this study, the characteristics of some filters for signal processing are investigated based on frequency response function. They include low-pass filters, band-pass filters, and notch filters. Especially, this study focuses on design parameters of their filters.

• Journal of Radiation Protection and Research
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• 제28권2호
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• pp.137-143
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• 2003

Annual radiation dose limit to radiation worker was substantially lowered in Korea by the adoption of 1990 recommendations of the International Commission on Radiation Protection (ICRP 60) in its legislation. On the other hand, radiation management environment in nuclear power plants is getting more worse because of the accumulation of radiation sources inside the system and the frequent need for maintenance according as the operation years of nuclear power plants increase. Therefore, Korea Hydro & Nuclear power Co., Ltd. (KHNP) has established a long-term 10 years plan from 2001 to 2010 for the reduction of radiation dose to workers. The plan is aimed for the reduction of annual dose per unit averaged over 5 years from 0.9 man-Sv in 2001 to 0.75 man-Sv in 2010 by radiation source reduction, equipment/tool improvement or new equipment development for easy maintenance, and the improvement of administration and system.

• Journal of Platform Technology
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• 제11권6호
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• pp.3-12
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• 2023

In today's system operation, it is difficult to detect failures and take immediate action in the case of a shortage of manpower compared to the number of equipment or failures in vulnerable time zones, which can lead to delays in failure recovery. In addition, various algorithms exist to detect abnormal symptom data, and it is important to select an appropriate algorithm for each problem. In this paper, an ensemble-based isolation forest model was used to efficiently detect multivariate point anomalies that deviated from the mean distribution in the data set generated to predict system failure and minimize service interruption. And since significant changes in memory space usage are observed together with changes in CPU usage, the problem is solved by using LSTM-Auto Encoder for a collective anomaly in which another feature exhibits an abnormal pattern according to a change in one by comparing two or more features. did In addition, evaluation indicators are set for the performance evaluation of the model presented in this study, and then AI model evaluation is performed.

• 문화기술의 융합
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• 제7권2호
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• pp.269-273
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• 2021

미(美) 육군은 21세기 최초로 모술이라는 대도시에서 공격작전을 실시하여 5가지의 도시 지역작전의 교훈을 도출하였다. 이를 바탕으로, 미(美) 육군은 무기체계, 싸우는 개념 및 구조 등 미래 메가시티 작전을 준비하기 위해 박차를 가하고 있다. 한편, 한반도 도시화가 급격히 진행되고 있으며 이로 인해 메가시티도 늘어날 전망이며 이에 한국 육군도 미(美) 육군을 벤치마킹하여 메가시티 작전을 다음과 같이 준비할 필요가 있다. 첫째, 미래 메가시티 작전을 준비하는 집단지성 플랫폼을 구축해야 한다. 둘째, 메가시티에 최적화된 군사력 건설(무기체계, 싸우는 개념, 구조)이 필요하다. 마지막으로, 전승(全勝)을 구현하기 위한 메가시티 합성훈련장을 구축해야 한다. 결국, 대한민국 육군은 이런 작전 준비를 통해 미래 전쟁에서 최종 승리를 담보할 수 있을 것이다.

• 한국농촌건축학회논문집
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• 제14권4호
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• pp.27-35
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• 2012

The purpose of this study was to establish planning criteria and development of type for the senior citizen who lives alone in home for the elderly at rural and fishing villages. In order to take most suitable co-housing, this analysis is progressed various building types based on aging in place and aging in health; self care, nono care, service care and community care. This paper is to suggest collective housing with 10 types in large scale and extracted 19 types in detail scale. The basis of classification are location condition; aging in place, building condition, health care condition; aging in health and possession & operation condition. In viewpoint of dwelling welfare 'Home for the Elderly' is to concerned with systematic methodology and architectural typology for senior citizen who lives alone in the rural and fishing village.

• 대한교통학회:학술대회논문집
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• 대한교통학회 1995년도 제27회 학술발표회
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• pp.35-56
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• 1995

이 글에서는 공항 여객터미날에 대한 계획 및 운영관리의 실행기준을 인지-반응모델을 이용하여 결정하는 방법을 논의하고자한다. 제시된 접근방법은 서비스의 폭을 승객의 입장에 따라 결정.분류하는 방법이다. 이것은 새로운 개념으로서 공항시스템의 특성을 고려하여 이용승객에 대한 직접적인 조사를 통해 각 시설별 수용능력 및 서비스 수준을 가늠할 수 있도록 도와준다. 이 접근방법에서는 이용자들의 서비스 기대치와 실질적인 서비스 제공에 따른 인식과의 차이를 통해 기준을 설정하는 것으로서 공항 계획자, 디자이너, 운영자 그리고 공항관리자들에게 실질적이고 용이한 기법으로 제공될 수 있다.

• Journal of Chest Surgery
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• 제26권7호
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• pp.526-531
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• 1993

Sixty-one consecutive patients with coronary artery bypass graft for myocardial revascularization were retrospectively reviewed to analyze various pattern of postoperative complication and death during hospital stay from Nov. 1988 to Oct. 1992. Fortytwo of the patients were male and nineteen female. The mean age was 56 and 51 years in male and female. Preoperative diagnosises were unstable angina in 14 of patients, stable angina in 28, postmyocardial infarction state in 15, and state of failed percutaneous transluminal coronary angioplasty in 4. 141 stenosed coronary arteries were bypassed with use of 20 pedicled internal mammary artery and 124 reversed saphenous vein grafts. Postoperative complications and perioperative death were as follows: 1. Of 61 patients undergoing operation, peri and postoperative over all complication occured in 15 patients [ 25% ]; newly developed myocardial infarction in 4, intractable cardiac arrhythmia including atrial fibrillation and frequent ventricular premature contraction in 3, bleeding from gastrointestinal tract in 2, persistent vegetative state as a sequele of brain hypoxia in 1, wound necrosis in 1, left hemidiaphragmatic palsy in 3 and poor blood flow through graft in 2. 2. Operative mortality was 8%[5 patients]. 3 out of these died in operating room; 1 patient by bleeding from rupture of calcified aortic wall, 1 by air embolism through left atrial vent catheter, 1 by low cardiac output syndrome. 2 patients died during hospital stay; 1 by acute respiratory distress syndrome with multiuple organ failure, 1 by brain death after delayed diagnosis of pericardial tamponade.

• 공학교육연구
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• 제5권2호
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• pp.54-62
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• 2002

이 연구에서는 국가기술자격의 분류체계가 21세기 산업구조와 기술변화에 부응할 수 있도록 하기 위해서 현행 26개로 설정되어 있는 직무분야의 적절성을 검토하였으며, 이에 터하여 국가기술자격제도 관리 운영의 효율성과 효과성을 높일뿐만 아니라 자격취득자의 취업을 촉진할 수 있는 새로운 직무분야 분류체계를 마련하고자 하였다. 이를 위하여 국가기술자격제도와 관련된 문헌 및 자료를 수집 분석하였고, 국가기술자격 직무분야의 적절성에 대한 전문가 의견 등을 수렴하여 26개 국가기술자격 직무분야를 13개 분야로 새롭게 구분 제시하였다.