• 제목/요약/키워드: Quantitative Approach

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단계적 최적립지 결정 방법에 관한 연구 (An Approach to Multi-Stage Decision Process for Optimum Location)

  • 김복만;김지일
    • 산업경영시스템학회지
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    • 제17권30호
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    • pp.11-24
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    • 1994
  • The problem of location for industries and residential quarters has undoubtedly been one of the most important factors to enhance human activities and standard of living. Nonetheless. there seem to be no such theories or approaches as to cope with this problem satisfactorily. As a matter of fact the evaluation of proposed locations so far has stuck to quantitative factors and thus the results are often rejected by the public or individuals. In deciding the location of industrial complex and/or residential quarters, the qualitative factors often play more important role than the quantitative factors. Moreover, it is quite possible for a proposed location to be disapproved for reasons other than quantifiable factors. This work presents an approach to multi-stage decision process of optimum location, particularly for residential quarters. The proposed approach consists of four stages. At the first stage, candidates for the location are searched and checked against musts. After this screening process, the candidates fulfilling the musts are evaluated both quantitatively and qualitatively at the second stage. The third stage is devoted to the integrated evaluation using diffrent weights for the two factors. At the final stage, a location is selected among the candidates evaluated at the earlier stages. This approach has been applied to and tested on a apartment-building project in Ulsan area. Difficulties arising from quantifying factors were encountered as expected. Sometimes decisions could be a matter of taste of the individuals concerned.

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위험도기반 가치공학적 기법을 적용한 고속도로 교통안전시설 최고가치평가 : 중앙분리대 적용사레를 중심으로 (Evaluation of Best Value for Safety Facilities on Highway Using Risk-based VE Approach - A Case Study of Median Barrier -)

  • 지동한;오영태;최현호;김성훈
    • 한국건설관리학회논문집
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    • 제9권1호
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    • pp.143-154
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    • 2008
  • 다양한 제반 위험요소가 상존하는 고속도로 교통안전시설의 안전에 대한 사회적 관심증가로 인하여 교통안전시 설에 대한 체계적인 성능, 비용 및 효과 분석 프로세스가 요구되어지고 있다. 교통안전시설은 도로사용자의 직 간접적인 사고위험성이 상존하는 중요한 시설물임을 고려하여 위험도의 정량적 평가에 대한 고려가 필수적이다. 본 연구에서는 교통안전시설의 가치분석 수행시 정량적 위험도분석 결과를 적용한 합리적인 가치분석(VE)기법을 제시하였으며, 고속도로 개선 전 후 중앙분리대에 적용하여 가치평가를 수행하였다. 또한 기능분석을 통해 중점개선대상 기능 도출기법을 제시하였으며, 이를 통해 개선 전 중앙분리대 문제점의 정확한 분석이 가능하며 향후 다양한 교통안전시설의 가치대안 창출 시 적용 가능하다.

하악골 골절 환자에서의 C-Reactive Protein의 변화 (THE CHANGES OF C-REACTIVE PROTEIN IN THE PATIENTS ASSOCIATED WITH MANDIBULAR FRACTURE)

  • 곽종민;김철환;김경욱
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제28권1호
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    • pp.35-41
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    • 2006
  • It is well known that concentration of C-reactive protein(CRP) in the serum increase as nonspecific reaction of the various tissue injury. The CRP, synthesized in the hepatocyte, is one of 'acute phase proteins' in the serum. The main signal patterns of this protein are regulated by synthesis of interleukin-I secreted from macrophage in the area of tissue injury. Many studies were performed for quantitative analysis for CRP according to various surgical operation, but the study for fracture patients associated with trauma, especially in mandible, are rare. The mandible fracture have intrinsic danger for infection in oral bacteria associated with open wound in oral cavity, and, are difficult for detection of tissue reaction between surgical swelling and infection by facial swelling. In this study, quantitative analysis for CRP associated tissue injury in mandibular fracture and surgical intervention was done, the results were as follows: 1. After initial mandibular trauma, the value of serum CRP diminished sequentially, most high value was presented in post-traumatic 2 days. 2. The CRP was diminished significantly 2 days after surgical intervention, and maintained normal value in 5 days after surgery. 3. The change of CRP are higher value in surgical intervention than initial trauma, it suggested that tissue injury from surgery was severe than trauma. 4. The high value of CRP was obtained in mandibular fracture combined soft tissue injury than no associated soft tissue injury. 5. In measurement of CRP according to surgical approach, highest serum value in patients of combined intra-oral and extra-oral approach was showed, and intra-oral approach, extra-oral approach, in sequential orders. 6. The CRP value are more higher in patient of 2 fracture site than only one fracture site. From the results obtained in this study, CRP has showed different values in mandibular fracture associated with severity of tissue injury and surgical intervention, and quantitative analysis of CRP value in serum can be applied to the clinical management of mandibular fracture.

Quantitative Analysis and Comparisons between In-Phase Control and Energy-Optimized Control for Series Power Quality Controllers

  • Xinming, Hunag;Jinjun, Liu;Hui, Zhang
    • Journal of Power Electronics
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    • 제9권4호
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    • pp.553-566
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    • 2009
  • In-phase control and energy-optimized control are the two major control strategies proposed for series power quality controllers (SPQC). However quantitative analysis and comparison between these two control strategies is quite limited in previous publications. In this paper, an extensive quantitative analysis is carried out on these two control strategies through phasor diagram approach, and a detailed quantitative comparison is conducted accordingly. The load current is used as the reference phasor, and this leads to a simpler and clearer phasor diagram for the quantitative relationship. Subsequently detailed analysis of SPQC using in-phase control and energy-optimized control are provided respectively, under different modes both for under voltage/voltage sag and for over voltage/voltage swell. The closed form analytic expressions and the curves describing SPQC compensation characteristics are obtained. The detailed system power flow is figured out for each mode, and the detailed quantitative comparison between the two control strategies is then carried out. The comparison covers several aspects of SPQC, such as required compensating voltage magnitude, required capacity of energy storage component, and maximal ride-through time. In the end, computer simulation and prototype experimental results are shown to verify the validity of all the analysis and the result of the comparison.

컴퓨터 단층 촬영 영상에서의 전이성 척추 종양의 정량적 분류를 위한 라디오믹스 기반의 머신러닝 기법 (Radiomics-based Machine Learning Approach for Quantitative Classification of Spinal Metastases in Computed Tomography)

  • 이은우;임상헌;전지수;강혜원;김영재;전지영;김광기
    • 대한의용생체공학회:의공학회지
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    • 제42권3호
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    • pp.71-79
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    • 2021
  • Currently, the naked eyes-based diagnosis of bone metastases on CT images relies on qualitative assessment. For this reason, there is a great need for a state-of-the-art approach that can assess and follow-up the bone metastases with quantitative biomarker. Radiomics can be used as a biomarker for objective lesion assessment by extracting quantitative numerical values from digital medical images. In this study, therefore, we evaluated the clinical applicability of non-invasive and objective bone metastases computer-aided diagnosis using radiomics-based biomarkers in CT. We employed a total of 21 approaches consist of three-classifiers and seven-feature selection methods to predict bone metastases and select biomarkers. We extracted three-dimensional features from the CT that three groups consisted of osteoblastic, osteolytic, and normal-healthy vertebral bodies. For evaluation, we compared the prediction results of the classifiers with the medical staff's diagnosis results. As a result of the three-class-classification performance evaluation, we demonstrated that the combination of the random forest classifier and the sequential backward selection feature selection approach reached AUC of 0.74 on average. Moreover, we confirmed that 90-percentile, kurtosis, and energy were the features that contributed high in the classification of bone metastases in this approach. We expect that selected quantitative features will be helpful as biomarkers in improving the patient's survival and quality of life.

복합체계의 정량적 상호운용성 평가 방법론 연구 (A Study on the Quantitative Interoperability Measurement Methodology of System of Systems)

  • 이진성;정찬기
    • 정보화연구
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    • 제9권2호
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    • pp.167-176
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    • 2012
  • 한국군은 LISI 모델을 활용하여 소요제기 및 획득단계에서 체계의 상호운용성 수준측정 및 평가를 실시하고 있다. 그러나 LISI 모델은 체계 간 상호운용성 평가에 초점이 맞추어져 있기 때문에 다수 체계가 유기적으로 연결된 복합체계의 상호운용성 평가에는 제한적이다. 또한 LISI 모델은 정량적이기 보다는 정성적인 접근방법이기 때문에 상호운용성 의사결정에 가시적인 정보 제공에는 한계가 있다. 이에 대한 해결책으로 본 연구에서는 복합체계의 정량적인 상호운용성 평가 방법론을 제안한다. 제안 방법론에서는 아키텍처를 활용하여 임무 프로세스를 지원하는 복합체계가 식별되고, 체계의 다중도와 유사도 계수를 기반으로 상호운용성 평가가 이루어진다. 그리고 제안 방법론의 효용성을 보이기 위해 사례연구 결과를 제시한다.

Optimal Design of Robust Quantitative Feedback Controllers Using Linear Programming and Genetic Algorithms

  • Bokharaie, Vaheed S.;Khaki-Sedigh, Ali
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.428-432
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    • 2003
  • Quantitative Feedback Theory (QFT) is one of most effective methods of robust controller design and can be considered as a suitable method for systems with parametric uncertainties. Particularly it allows us to obtain controllers less conservative than other methods like $H_{\infty}$ and ${\mu}$-synthesis. In QFT method, we transform all the uncertainties and desired specifications to some boundaries in Nichols chart and then we have to find the nominal loop transfer function such that satisfies the boundaries and has the minimum high frequency gain. The major drawback of the QFT method is that there is no effective and useful method for finding this nominal loop transfer function. The usual approach to this problem involves loop-shaping in the Nichols chart by manipulating the poles and zeros of the nominal loop transfer function. This process now aided by recently developed computer aided design tools proceeds by trial and error and its success often depends heavily on the experience of the loop-shaper. Thus for the novice and First time QFT user, there is a genuine need for an automatic loop-shaping tool to generate a first-cut solution. In this paper, we approach the automatic QFT loop-shaping problem by using an algorithm involving Linear Programming (LP) techniques and Genetic Algorithm (GA).

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개선된 RBI 기법을 이용한 석유화학설비의 위험도평가 (Risk Assessment of Petrochemical Equipments Using Enhanced RBI Technique)

  • 이상민;송기훈;장윤석;최재붕;김영진;한상인;최송천
    • 대한기계학회논문집A
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    • 제29권10호
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    • pp.1392-1398
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    • 2005
  • API 581 guideline provides a methodology for calculating the risks of equipments in refinery or petrochemical plant. However, especially in part of the consequence of failure, there is a major limitation of its application to the petrochemical plant directly since only a representative material is considered in calculating the risk while the equipment is composed of numerous materials. The objectives of this paper are to propose an enhanced risk-based inspection (RBI) technique to resolve shortcomings inclusive of the above issue and to assess the risks of typical petrochemical equipments. In this respect, a program incorporating material database was developed to fully incorporate the characteristics of different materials. The proposed RBI program consists of qualitative, semi-quantitative and quantitative risk evaluation modules in which toxic materials as well as representative materials were selected automatically for comparison to those in the current guideline. It has been applied to assess the risks of equipments in ethylene facilities of petrochemical plants. Thereby, more realistic evaluation results were obtained and applicability of the proposed RBI program was proven.

A New Variable Selection Method Based on Mutual Information Maximization by Replacing Collinear Variables for Nonlinear Quantitative Structure-Property Relationship Models

  • Ghasemi, Jahan B.;Zolfonoun, Ehsan
    • Bulletin of the Korean Chemical Society
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    • 제33권5호
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    • pp.1527-1535
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    • 2012
  • Selection of the most informative molecular descriptors from the original data set is a key step for development of quantitative structure activity/property relationship models. Recently, mutual information (MI) has gained increasing attention in feature selection problems. This paper presents an effective mutual information-based feature selection approach, named mutual information maximization by replacing collinear variables (MIMRCV), for nonlinear quantitative structure-property relationship models. The proposed variable selection method was applied to three different QSPR datasets, soil degradation half-life of 47 organophosphorus pesticides, GC-MS retention times of 85 volatile organic compounds, and water-to-micellar cetyltrimethylammonium bromide partition coefficients of 62 organic compounds.The obtained results revealed that using MIMRCV as feature selection method improves the predictive quality of the developed models compared to conventional MI based variable selection algorithms.