• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2008년도 춘계학술대회논문집
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• pp.84-87
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• 2008

The sulfur oxides is one of important materials to come about air pollution at thermal plant consuming fossil fuel. The several flue gas desulfurization equipments are installed and operated to decrease sulfur oxides. The flue gas desulfurization of our thermal plant is designed for optimizing flue gas desulfurization technical development and research by Korea Electric Power Research Institute. We operate this desulfurization equipment. Now, our country imports nearly 97 percentage of the energy source and competes with the world for the energy because of the rise of raw materials cost. The fuel cost decrease of power plants is the most important factor of the operation. The fuel used in the experiment is the domestic anthracite from Kangwon Taeback and the bituminous coal from Russia,Taldinsky Mine. This Study is experimental investigations of desulfurization characteristics for domestic anthracite power plant by increasing bituminous coal. We surveyed possible parameters and conducted the performance about desulfurization equipment in Y.D thermal power plant.

• 한국정밀공학회지
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• 제27권12호
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• pp.75-83
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• 2010

Every mechanical part for mass production has dimensions with tolerances in engineering drawing. Tolerance is given to guarantee assemble parts together satisfying functional requirements and dimensional constraints. Tolerance is essential factor for standardization of parts or assembly and has huge influence on manufacturing cost. It will be desirable to have tolerances as broad as possible for minimizing manufacturing cost. This paper describes tolerance analysis of u-joint assembly that is a part of automobile steering system. Within the range of tolerances of parts, accumulated effect is estimated by arithmetic calculation, probability theory and Monte carlo simulation. Each result is compared to investigate the method for increasing productivity.

• 통상정보연구
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• 제13권2호
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• pp.95-117
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• 2011

본 연구는 국제물류주선업체가 정기해운선사를 선택함에 있어 어떠한 요인들이 중요시되는가를 계층분석적의사결정법(AHP)을 이용하여 그 요인별 우선순위를 도출하고, 정기해운선사별 요인의 중요도를 평가함으로써 그들의 고객인 국제물류주선업체의 요구를 효율적으로 충족시킬 수 있는 방안을 수립하는 기초자료를 제공하고자 한다. 서울 부산지역 국제물류주선업체에 7년 이상 종사하고 있는 전문가 50명을 대상으로 면접, FAX, e-mail을 통해 설문지를 배포하였고 회수된 유효설문 26부의 응답 자료를 분석에 사용하였다. 분석결과를 살펴보면, 최적의 정기해운선사 선택을 위한 주요 항목의 평가에서는 비용요인의 중요도가 가장 높게 나타났으며, 운송요인, 서비스 요인, 프로모션 요인 순으로 나타났다. 세부평가 속성의 종합 중요도에서는 전체 지출 비용, 운임협상의 합리 신속성, 고객관리서비스, 운항스케줄의 정시성 순으로 높게 나타났으며, 반면 광고 및 PR, 부가서비스, 운송시설 및 장비 순으로 낮은 중요도를 보였다.

• 대한간호학회지
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• 제45권3호
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• pp.429-438
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• 2015

Purpose: This study was conducted to develop key performance indicators (KPIs) for home care nursing (HCN) based on a balanced scorecard, and to construct a performance prediction model of strategic objectives using the Bayesian Belief Network (BBN). Methods: This methodological study included four steps: establishment of KPIs, performance prediction modeling, development of a performance prediction model using BBN, and simulation of a suggested nursing management strategy. An HCN expert group and a staff group participated. The content validity index was analyzed using STATA 13.0, and BBN was analyzed using HUGIN 8.0. Results: We generated a list of KPIs composed of 4 perspectives, 10 strategic objectives, and 31 KPIs. In the validity test of the performance prediction model, the factor with the greatest variance for increasing profit was maximum cost reduction of HCN services. The factor with the smallest variance for increasing profit was a minimum image improvement for HCN. During sensitivity analysis, the probability of the expert group did not affect the sensitivity. Furthermore, simulation of a 10% image improvement predicted the most effective way to increase profit. Conclusion: KPIs of HCN can estimate financial and non-financial performance. The performance prediction model for HCN will be useful to improve performance.

• 정보처리학회논문지D
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• 제11D권1호
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• pp.163-172
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• 2004

객체지향 개발 방법론을 적용하는 소프트웨어 개발 프로젝트에서 개발 노력 추정 기법으로 사용사례점수(UCP, Use Case Point)에 대한 연구가 계속되고 있다. 기존의 연구는 기술적 요인과 환경적 요인을 적용한 AUCP(Adjusted Use Case Point)에 상수를 곱하여 개발 노력을 계산하는 선형모델을 제시하고 있으나, AUCP와 UUCP(Unadjusted Use Case Point)를 이용하여 개발노력을 추정하는 통계적인 모델은 제시되지 않고 있다. 소프트웨어 규모가 증가함에 따라 개발 기간이 기하급수적으로 증가하는 선형 회귀모델이 부적합하다는 사실과 UCP 계산과정에서 TCF(Technical Complexity Factor)와 EF(Environmental Factor)를 적용에 따른 FP(Function Point) 오차 발생 문제점을 확인하였다. 이 논문은 사용사례점수를 기반으로 하여 기존 연구의 문제점인 TCF와 EF를 고려하지 않고 직접 UUCP로부터 개발 노력을 추정한 수 있는 선형, 로그형, 다항식, 거듭제곱 및 지수함수 회귀모델의 성능을 평가한 결과, 가장 적합한 모델로 지수형태의 비선형 회귀모델을 도출하였다.

• Transactions on Control, Automation and Systems Engineering
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• 제3권4호
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• pp.268-271
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• 2001

In this paper, we propose a simplified pollution adaptive mesh generation algorithm using singular elements. The algorithm based on the element pollution error indicator concentrate on boundary nodes. The automatic mesh generation method is followed by either a node-relocation or a node-insertion method. The boundary node relocation phase is introduced to reduce pollution error estimates without increasing the boundary nodes. The node insertion phase greatly improves the error and the factor with the cost of increasing the node numbers. It is shown that the suggested r-h version algorithm combined with singular elements converges more quickly than the conventional one.

• KIEE International Transaction on Electrical Machinery and Energy Conversion Systems
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• 제5B권4호
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• pp.374-381
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• 2005

The ability to provide quality power has become a significant issue in power systems. The main causes of poor power quality are harmonic currents, poor power factor, supply-voltage variations, etc. A technique of achieving both active current distortion compensation, power factor correction and also mitigating the supply-voltage variation (sag or swell) at the load side is presented in this paper. The operation and rating issues of the proposed Single-phase Unified Power Quality Conditioner are also highlighted. To reduce the total cost while simultaneously increasing the performance, the system is fully digitally controlled using the fixed-point TMS320F240 digital signal processor. The performances of the UPQC, which is composed by shunt and series PWM controlled-converters, have been verified on a laboratory prototype.

• 터널과지하공간
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• 제30권1호
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• pp.63-75
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• 2020

터널 발파의 최외곽에서 발생할 수 있는 과대 여굴은 작업자 및 장비의 안전에 저해되며 숏크리트 등 지보량의 증가로 공사 비용이 증가시키는 주요 원인이다. 이러한 여굴은 화약 에너지와 암반의 특성 간의 복잡한 발생 메커니즘으로 인해 완벽한 제어가 매우 어렵다. 본 연구는 여굴 발생의 중요한 원인인 암반의 공학적 특성 중 무지보 막장 상태, 단축압축강도, 풍화도 및 불연속면의 특성(빈도, 상태 및 불연속면과 최외곽선과의 각도) 등과 발생한 여굴의 깊이와의 관계를 feed-forward 인공신경망을 통해 분석하였다. 이를 통해 통해 얻어진 각 인자의 가중치를 기초로 여굴저항도(Overbreak Resistance Factor: ORF)를 개발하였다. 더불어 여굴저항도를 이용한 터널 발파 여굴 관리 시스템을 제안한다.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.493-498
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• 2009

Recently, the number of complex construction projects, such as high-density development and long-span mega structure construction, has been increasing globally. Therefore, the construction duration has become an even more important factor for success. Nevertheless, in domestic residential construction projects, it usually takes more time than twice as much as North American cases. The long construction duration causes a number of problems, for example growth of financial costs, fall in productivity, and weakness of competitiveness. If the framework construction duration can be shortened to 3 ~ 4 days, then it is also expected to complete the finish work of building in shorter duration, be led to reduce the entire construction duration, and eventually to save a great deal of indirect costs. For shortening the construction duration, previous researches pointed out that the development of simplified plan design should precedes. But, in reality, lack of experience of new design and innovative techniques tends to be the obstacle to wide adoption of the simplified plan design in construction fields. In this paper, a simplified structural plan design is proposed, and the construction cost is quantitatively compared between when traditional construction technique is applied to the traditional plan and when the duration-shortening key technique is applied to the developed plan.

• 토지주택연구
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• 제9권4호
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• pp.33-42
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• 2018

As a radiant heating panel gets more popularity, the need to study on evaluation method of thermal output of the panel also becomes increasing. Generally, the chamber using method is applied to evaluate the thermal output through an experiment. However, the chamber using method cannot be used due to the limitations on space and cost. EN1264 addresses the test equipment to evaluate the thermal output by using simpler experimental setup, and introduces application method in detail. However, there is not enough description of control methods to meet the experiment condition, and it is difficult to meet this when practical experiment. Therefore, this paper analysed the control error factors of when the thermal output experiment is performed. When EN1264 method is applied to evaluate the thermal output of the radiant floor heating panel, the error factor which is caused by the characteristic of test equipment cannot be removed by the control methods of chamber using method. In addition, the error factor can be occurred at the element which is located out of the control system. These possible error factors are defined as the characteristic error factors.