• 제목/요약/키워드: Feasibility improvement

검색결과 690건 처리시간 0.027초

가속도계 및 변위계를 이용한 차량용 고무부시의 변형량 추정 가능성 연구 (A Feasibility Study on Estimation of the Deformation of Rubber Bush in Vehicles Using Acceleration and Displacement Signals on the Links)

  • 송승호;김광준
    • 한국소음진동공학회논문집
    • /
    • 제26권7호
    • /
    • pp.827-835
    • /
    • 2016
  • Ride comfort of a vehicle is often determined by rubber bushes in suspension system. If transmission forces versus deformations across the bushes are available under operational conditions, improvement of the ride comfort could be done with more ease. Recently, the transmission forces are measured using custom-made force transducers inside the links. This study presents a feasibility study on estimation of the rubber bush deformations using vibration signals on the rigid links. Linear variable displacement transducers as well as piezoelectric accelerometers are used to expand frequency range to very low frequency, which cannot be done with accelerometers only. How to estimate the bush deformation from the two vibration signals on the links are presented together with experimental results.

Methodological Improvement for the Economic Assessment of Public R&D Programs

  • Hwang, Seogwon
    • STI Policy Review
    • /
    • 제2권3호
    • /
    • pp.35-44
    • /
    • 2011
  • Korea has rapidly increased R&D investment over the last few decades and the intensity of R&D investment is among the highest in the world; however, there are serious concerns about R&D performance and R&D efficiency. This study is to improve the economic assessment methodology regarding a feasibility study for national R&D programs that are thought to be one of the most prominent ways to enhance R&D efficiency. In order to improve the methodology of economic assessment, a few of important factors such as technical or market uncertainty, spillover effect, and R&D contribution ratio should be covered in the model. The focus of this article is technological and market uncertainty that has a close relation with strategic flexibility and utilization potential to increase the value of R&D programs. To improve the current linear and definitive R&D process, a new framework with strategic flexibility is suggested, in which the result of economic assessment that considers technological and market uncertainty is reflected in planning. That kind of feedback process is expected to enhance the value of the program/project as well as R&D efficiency.

철도투자 효율성 향상을 위한 투자전략에 관한 연구 (A Study on the Investment Strategy that improves the Rail-infrastructure Investment Efficiency)

  • 김성;이종국;김윤양
    • 한국철도학회:학술대회논문집
    • /
    • 한국철도학회 2008년도 춘계학술대회 논문집
    • /
    • pp.1574-1586
    • /
    • 2008
  • Railway is the most effective transportation than any other traffic. But due to the its expensive maintenance fee and various components like roadbed, rail, rollingstock, electric and signal etc, the construction cost of the railway is usually higher than highway. Such a reason, a lot of cost and period are needed to complete the railway project. In addition that considering the decreasing of the SOC budget, the investment in the railway industry is getting hard than ever. This study analyzed the cost, term of work, freight & passenger transportation demand of the wide area railway electrification project and main line improvement project. And it compared the estimation value and real value of the projects like cost and period etc. And this study surveyed the economic feasibility including factors which are not considered in the feasibility study guide. With those results, This study suggest the project management and evaluation method to enlarge the efficiency of the railway construction project.

  • PDF

풍력발전사업 에너지생산량 산정 오차가 사업성지표에 미치는 영향 및 AHP를 이용한 중요인자 분석 (Influences of Energy Production Estimation Errors on Project Feasibility Indicators of a Wind Project and Critical Factor Analysis by AHP)

  • 김영경;장병만
    • 경영과학
    • /
    • 제30권2호
    • /
    • pp.1-10
    • /
    • 2013
  • Case studies are made to investigate the relationship between the accuracy of energy production estimation and project feasibility indicators such as rate of return on equity (ROE) and debt service coverage ratio (DSCR) for three wind farm projects. It is found out that 1% improvement in the accuracy of energy production estimation may enhance the ROE by more than 0.5% in the case of P95, thanks to improved financing terms. AHP survey shows that MCP correlation of measured in situ wind data with long term wind speed distribution and hands-on experiences of flow analysis are more important than other factors for more precise annual energy production estimation.

기술평가지표와 기업성과의 관계비교분석 -초기중소벤처와 성장중소벤처- (The Comparative Study of the relationship between Technology Valuation Index and performance in Ventures)

  • 양동우
    • 기술혁신학회지
    • /
    • 제8권3호
    • /
    • pp.1175-1198
    • /
    • 2005
  • The objective of the study is to verify the relationship between technology valuation indexes and corporate's performance in ventures by business operating periods. The result of the study is expected to be useful in loan evaluation, investment decision, internal management decision making and business improvement. The results of study is as follows. First, in early stage ventures, we find that three major valuation index(technology feasibility, economic efficiency, productivity) are significant ex-ante variables which are discriminating between firms' going concern and firms' failure. Second, in growth stage ventures, we find that three major valuation index(business feasibility, general marketability, technology marketability) are significant ex-ante variables which are discriminating between firms' going concern and firms' failure. Third, in early stage ventures, we find that at least thirty-eight minor valuation index elements are significant ex-ante variables which are discriminating between firms' going concern and firms' failure and in growth stage ventures, thirty-one minor valuation index elements are significant in various analysis' results.

  • PDF

예비타당성조사 R&D 중복성 검토의 판단 및 개선 방안에 대한 연구 : 조사 담당자의 설문 응답 기반 분석 (Study on Judgement and Improvement of R&D Overlap Analysis during National R&D Pre-feasibility Study : Analysis based on Survey Response of Pre-feasibility Studying Team)

  • 박창현
    • 한국기술혁신학회:학술대회논문집
    • /
    • 한국기술혁신학회 2017년도 추계학술대회 논문집
    • /
    • pp.535-546
    • /
    • 2017
  • 국가 R&D 사업에 대한 예비타당성조사 시 R&D 중복성에 대한 검토는 중복된 투자를 방지하여 재정 투자의 효율성을 높이는데 중요하다. 본 연구에서는 예비타당성조사 담당자들을 대상으로 중복성 검토에 대한 중요요인, 개선사항, 판단기준, 판단주체에 대한 설문조사 분석을 진행하였고, 외부 전문가 그룹의 인식차이와 비교하였다. 설문조사 결과에 대한 통계 분석을 통해 중복성 검토에서 가장 중요한 요인은 '중복성 판단기준, 시스템의 데이터베이스 및 검색 알고리즘'으로 확인되었고, 3가지 요인에 대한 개선이 중복성 검토를 개선하는데 가장 중요함을 확인하였다. 또한 다중회귀분석을 통해 주요 요인들이 중복성 검토결과의 정확성에 미치는 영향성을 분석하여 요인들의 유의성에 대해 확인하였다. 본 연구를 통해 예비타당성 조사 시 R&D 중복성에 대한 검토가 향후 어떤 방향으로 개선되어야하는지에 대해 시사점이 제시된다.

  • PDF

Domain Adaptation for Opinion Classification: A Self-Training Approach

  • Yu, Ning
    • Journal of Information Science Theory and Practice
    • /
    • 제1권1호
    • /
    • pp.10-26
    • /
    • 2013
  • Domain transfer is a widely recognized problem for machine learning algorithms because models built upon one data domain generally do not perform well in another data domain. This is especially a challenge for tasks such as opinion classification, which often has to deal with insufficient quantities of labeled data. This study investigates the feasibility of self-training in dealing with the domain transfer problem in opinion classification via leveraging labeled data in non-target data domain(s) and unlabeled data in the target-domain. Specifically, self-training is evaluated for effectiveness in sparse data situations and feasibility for domain adaptation in opinion classification. Three types of Web content are tested: edited news articles, semi-structured movie reviews, and the informal and unstructured content of the blogosphere. Findings of this study suggest that, when there are limited labeled data, self-training is a promising approach for opinion classification, although the contributions vary across data domains. Significant improvement was demonstrated for the most challenging data domain-the blogosphere-when a domain transfer-based self-training strategy was implemented.

A FEASIBILITY STUDY ON THE NUMERICAL PRE-ASSEMBLY SIMULATION USING 3D LASER SCANNING MEASUREMENT

  • Kyoungmin Kim ;Seok Kim ;Chan-Hyuk Park ;Kyong Ju Kim
    • 국제학술발표논문집
    • /
    • The 1th International Conference on Construction Engineering and Project Management
    • /
    • pp.1193-1198
    • /
    • 2005
  • The pre-assembly takes a large portion of the fabrication cost of steel bridges. In order to save the fabrication cost through the improvement of the conventional pre-assembling process, this research investigates a numerical pre-assembly simulation as an alternative to current pre-assembling process. The 3D laser scanning was utilized in site and measuring data for steel box were analyzed. The productivity of pre-assembly simulation system is compared with the conventional pre-assembling system. This paper identifies feasibility on the alternative pre-assembling process and then proposes the scheme of the pre-assembly simulation system development satisfying the current pre-assembly inspection of standards.

  • PDF

스마트도로 안전성 향상 효과의 정량화 연구 (Quantitative Analysis of Safety Improvement on Smart Roads)

  • 장현호;백승걸;오성호;김호정
    • 한국ITS학회 논문지
    • /
    • 제10권4호
    • /
    • pp.44-54
    • /
    • 2011
  • 첨단도로 안전시설물, 첨단교통관리기법 등을 기반으로 하는 다양한 첨단 교통서비스는 교통사고 등의 돌발상황을 감소시킬 것으로 예상되며, 이에 따라 도로의 지 정체 역시 감소될 것이다. 따라서 안전성 향상에 따른 지 정체 감소효과를 편익항목에 포함시킬 수 있다. 그러나 현재 우리나라의 투자평가지침에서는 이를 편익으로 계상하지 않고 있다. 스마트도로에서 제공하는 첨단 교통서비스는 인프라의 초기 투자비용을 상승시키지만 새로운 서비스로 인한 편익이 계상되지 않아 비용/편익 분석 시에 경제성을 확보하지 못하는 문제점을 가지게 된다. 따라서 본 연구는 과거 3년간의 고속도로 사고 자료를 이용하여 평균 차로차단시간을 추정하고, 미시적 시뮬레이션을 이용하여 구축된 자료와 회귀분석기법을 통해 지체시간 추정모형을 개발하였다. 또한 개발된 모형이 투자평가기법에 적용될 수 있도록 계량화에 필요한 원단위(평균용량감소비율 등)를 제시하였다. 개발된 방법론을 스마트하이웨이사업 사례에 적용 결과, 스마트 안전시설로 인한 사고감소율을 10%로 가정하였을 경우, 30년 동안 총 안전성 향상 편익은 1,392억 원에 이르는 것으로 분석되었다.

상호 결합이 적은 두 개의 공진점을 갖는 수중용 광대역 전기 음향 변화기를 위한 역률 개선 회로 설계 및 실험 (The Design and Experiment of Power Factor Improvement Circuit for a Underwater Electro Acoustic Transducer with Low Coupled Dual Resonances)

  • 임준석;편용국
    • 한국통신학회논문지
    • /
    • 제38B권12호
    • /
    • pp.967-975
    • /
    • 2013
  • 수중용 전기 음향 변환기용 외부 회로를 구성할 때, 파워 앰프의 내부저항이 매우 작은 경우 정합 회로를 구성하기 보다는 부하측의 역률을 개선하는 것을 선호 한다. 기존 연구의 결과를 살펴보면 광대역에서 최대 파워를 전달하게 하는 정합회로를 구하는 방법을 많이 연구되어 왔으나, 두 개의 공진점을 갖는 수중용 광대역 전기 음향 변화기에 적용할 만한 광대역 역률 개선 튜닝 회로를 구성하는 방법은 논문화된 결과는 드물다. 본 논문에서는 기존의 정합회로 설계에서 사용하는 체비세프 설계법을 기본으로 하여, 좀 더 낫은 결과를 가질 수 있도록 하는 복합 최적화 과정을 바탕으로 역률 개선 회로를 설계하고 이를 실험을 통하여 역율 개선을 확인한다.