• 대한토목학회논문집
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• 제30권6D호
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• pp.655-662
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• 2010

사회기반시설은 국가 경쟁력 지표로써, 전통적으로 정부의 SOC 재정으로 건설되어 왔다. 그러나 SOC 예산 축소에도 불구하고 사회기반시설의 확충 요구를 해결하기 위해 민간투자사업제도가 도입되었으며, 이 중 도로사업의 비중이 높다. 본 연구는 기 제안된 도로사업 사업계획서의 운영관리비와 사업계획서와 연계되는 재무모델의 운영관리비 항목을 분석하고, 도로사업의 특성을 반영하기 위해 한국도로공사의 사업비 항목과 운영관리 업무를 분석하였다. 분석 결과를 통해 분류체계를 마련하여 비용산정 기준을 마련하는 것이 요구된다. 또한 업무의 효율성을 고려하여 기존의 업무 도구를 웹기반으로 통합하여 하나의 시스템으로 개발하는 것을 제안하였다. 이를 통해 민간투자사업의 전체적인 사업성 확보에 기여하고, 수익성을 기반으로 하는 사회기반시설의 확충에 기여할 것으로 기대된다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1997년도 추계학술대회 논문집
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• pp.145-149
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• 1997

STEP AP224 includes the information of machining feature and tolerances. Machining features are machined from raw material. Tolerance constrain feasible methods of manufacture, strongly influence the cost of manufacture. And tolerances influence the machining process. We need to decide the precedence between features .tool radius and tool direction for minimum tool changes. This paper deals with the method of decision of precedence between features and process parameters using feature information and tolerances in STEP AP224.

• 산업경영시스템학회지
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• 제8권12호
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• pp.119-125
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• 1985

It is very important to assure the software quality. The static and dynamic testing are to be performed on the program to find some error in it, and it's purposes are to assure the software quality with cost-effectiveness. For it we use the automated tool. In this paper, it suggest the design of the software tool for COBOL static testing.

• 한국항공우주학회지
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• 제43권9호
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• pp.787-798
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• 2015

중 소형위성은 적은 비용으로 단기간에 개발 및 운용할 수 있어야 한다. 하지만 개발 초기 단계에서 임무를 설계하고 분석하는 과정과 위성시스템의 개념설계를 수행하는 과정을 반복 수행하면서 사용자의 요구사항을 맞추고, 개발방향을 정립하는 과정에서 많은 시간과 비용이 소요하게 된다. 본 연구에서는 이러한 초기 단계에서 소요되는 시간과 비용을 줄이기 위해 GUI(Graphical User Interface) 기반의 소프트웨어인 SCDT(Spacecraft Cenceptual Design Tool)를 개발하였다. GUI 기반의 소프트웨어는 입력된 값들의 수정이 용이하고 다양한 방법으로 사용자에게 결과를 보여줄 수 있다. 본 논문에서는 MATLAB GUI 기반의 SCDT를 개발한 과정 및 개발된 SCDT GUI를 소개한다.

• 한국건설관리학회논문집
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• 제15권2호
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• pp.53-61
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• 2014

건설 프로젝트는 생산과정 이전에 설계도면을 바탕으로 예상되는 비용이 산정되며, 기획단계는 소요예산을 책정하고 설계단계는 예산에 합당한 효율적 대안을 찾으며, 정확한 입찰금액을 예측하기 위해 수차례 이루어진다. 특히, 물량산출 이전까지 예측되는 공사비의 정확도와 신뢰도는 매우 중요하다. 그러나 국내의 경우 면적당 단가 방식 공사비 예측을 벗어나지 못할 뿐 아니라, 단계별 예측방법, 프로세스, 데이터 분석 및 관리기술 등이 표준화되어 체계적이고 종합적으로 관리되지 못하고 있다. 그리고 복합용도 프로젝트에서의 견적은 그 사례도 적고 단가정보를 얻기가 매우 어렵다. 이에 국내 복합용도 프로젝트 공사비 예측기술 및 관리기술 발전을 위하여 BIM의 공간정보를 활용한 내부마감 개략견적 코스트 모델을 개발하여 제시하였다.

• Journal of Astronomy and Space Sciences
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• 제37권3호
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• pp.187-197
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• 2020

In order to avoid the high cost and high risk of demonstration mission of rendezvous-docking technology, missions using nanosatellites have recently been increasing. However, there are few successful mission cases due to many limitations of nanosatellites like small size, power limitation, and limited performances of sensor, thruster, and controller. To improve the probability of rendezvous-docking mission success using nanosatellite, a rendezvous-docking phase analysis tool for nanosatellites is developed. The tool serves to analyze the relative position and attitude control of the chaser satellite at the docking phase. In this tool, the Model Predictive Controller (MPC) is implemented as a controller, and Extended Kalman Filter (EKF) is adopted as a filter for noise filtering. To verify the performance and effectiveness of the developed tool for nanosatellites, simulation study was conducted. Consequently, we confirmed that this tool can be used for the analysis of relative position and attitude control for nanosatellites in the rendezvous-docking phase.

• 한국생산제조학회지
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• 제20권1호
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• pp.53-59
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• 2011

End milling is available for machining the various shape of products and has been widely applied in many manufacturing industries. The quality of products depends on a machine tool performance and machining conditions. Recognition characteristics of the cutting condition is becoming a critical requirement for improving the utilization and flexibility of present-day CNC machine tools. The measurement of tool wear would be performed by coordinate-measuring machine(CMM). However, the usage of CMM requires much time and cost. In order to overcome the difficulties, on-line measurement(OLM) system was applied for a tool wear measurement. This study shows a reliable technique for the reduction of machining error components by developing a system using a CCD camera and machine vision to be able to precisely measure the size of tool wear in flat end milling for CNC machining. The CCD camera and machine vision attached to a CNC machine can determine tool wear quickly and easily.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1907-1910
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• 2003

Miniaturized machine tool can be used to produce 3D features based on CNC and PC-NC technology in the micro/meso scale. Wide applications of CNC technology are developed and there are lots of know-hows in the cutting process and their CNC application. It helps micro/meso scale structure to machine components, which can be used directly for practical applications. In the present research, as the machine tool is miniaturized, the manufacturing machine tools costs less when compared to the equipment used in other micromachining technologies. Moreover, with advancement of micro tool technology, the cutting process can be used to produce micro/meso scale parts. In conclusion, the proposed system can reduce the cost by utilizing the current machining technology, and as a result, complex micro/meso parts can be produced efficiently with high productivity.

• 한국정밀공학회지
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• 제15권11호
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• pp.189-198
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• 1998

Recently, monitoring of tool life is a matter of common interesting because tool life affects precision, productivity and cost in machining process. Especially flank wear has a direct effect on cutting mechanism, so the various pattern of cutting force is obtained experimentally according to variation of wear condition. By investigating cutting force signal, AR(Autoregressive) modeling and correlation dimension analysis is conducted in turning operation. In this modeling and analysis, we extract features through 6th AR model, correlation integral and normalized correlation integral. After the back-propagation model of the neural network is utilized to monitor tool life according to flank wear. As a result. a very reliable classification of tool life was obtained.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2009년도 추계학술발표대회 논문집
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• pp.394-399
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• 2009

Since some decades ago, there has been a concern for resource depletion and environmental pollution associated with building properties. In addressing such impact of the built environment, there is a recognition of the existence of alternative building materials, fuels for energy supply as well as technologies for waste handling and disposal. Nevertheless, for long time, the choice between such alternatives was dictated by factors such as differences in prices and aesthetic values. A new important dimension in discriminating between different options is the environmental dimension. This aspect is important since buildings are one of the spatially big new additions to the natural environment that consume a lot of materials and energy during their long lifetime. Thus, with the environmental dimension kept in mind, a existing cost estimation needs to be changed. A new cost assessment method, Life Cycle Cost, should calculate overall costs with dimensional factors: investment and utility costs as well as maintenance costs over the lifetime of the building. Aiming to give an overview of the present status of Building Life Cycle Assessment(LCA) tools as a basis for further research and development including economic performance, this paper describes and compares 3 different tools for Life Cycle Assessment(LCA) and economic analysis of the green buildings. This paper compared these approaches based on various aspects. These include economic analysis method, evaluation duration, data of results(index). Use of the comparison analysis is to produce a better picture and indicate profits and shortcomings for the tools as a group; thus providing important direction improvement of LCA tool as well as further research and development of this group of tools.