• 제목/요약/키워드: Quantitative Approach

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AHP-Based Evaluation Model for Optimal Selection Process of Patching Materials for Concrete Repair: Focused on Quantitative Requirements

  • Do, Jeong-Yun;Kim, Doo-Kie
    • International Journal of Concrete Structures and Materials
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    • 제6권2호
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    • pp.87-100
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    • 2012
  • The process of selecting a repair material is a typical one of multi-criteria decision-making (MCDM) problems. In this study Analytical Hierarch Process was applied to solve this MCDM problem. Many factors affecting a process to select an optimal repair material can be classified into quantitative and qualitative requirements and this study handled only quantitative items. Quantitative requirements in the optimal selection model for repair material were divided into two parts, namely, the required chemical performance and the required physical performance. The former is composed of alkali-resistance, chloride permeability and electrical resistivity. The latter is composed of compressive strength, tensile strength, adhesive strength, drying shrinkage, elasticity and thermal expansion. The result of the study shows that this method is the useful and rational engineering approach in the problem concerning the selection of one out of many candidate repair materials even if this study was limited to repair material only for chloride-deteriorated concrete.

A Study on the Development of Robust Fault Diagnostic System Based on Neuro-Fuzzy Scheme

  • Kim, Sung-Ho;Lee, S-Sang-Yoon
    • Transactions on Control, Automation and Systems Engineering
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    • 제1권1호
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    • pp.54-61
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    • 1999
  • FCM(Fuzzy Cognitive Map) is proposed for representing causal reasoning. Its structure allows systematic causal reasoning through a forward inference. By using the FCM, authors have proposed FCM-based fault diagnostic algorithm. However, it can offer multiple interpretations for a single fault. In process engineering, as experience accumulated, some form of quantitative process knowledge is available. If this information can be integrated into the FCM-based fault diagnosis, the diagnostic resolution can be further improved. The purpose of this paper is to propose an enhanced FCM-based fault diagnostic scheme. Firstly, the membership function of fuzzy set theory is used to integrate quantitative knowledge into the FCM-based diagnostic scheme. Secondly, modified TAM recall procedure is proposed. Considering that the integration of quantitative knowledge into FCM-based diagnosis requires a great deal of engineering efforts, thirdly, an automated procedure for fusing the quantitative knowledge into FCM-based diagnosis is proposed by utilizing self-learning feature of neural network. Finally, the proposed diagnostic scheme has been tested by simulation on the two-tank system.

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Post-modernism 의 발생과 실내디자인의 수용에 관한 연구-모더니즘과 해체주의 실내 건축양식의 정량적 분석 및 해석을 중심으로 (A Study on the Origination of Post-Modernism and Its Acceptance on Interior Design -Concentrated on the Quantitative Analysis and Interpretation of Modern and Neo-Modern Interior Architectural Style-)

  • 이춘섭
    • 한국실내디자인학회논문집
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    • 제8호
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    • pp.32-38
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    • 1996
  • The main focus of this paper is to apply contemporary aesthetics and psychological study with interior design analysis. Up to now, the methodology of interior design analysis has been developed toward a more qualitative way. By the virtue of the perception , congnition , and information theory, which oriented toward a quantitative approach, it became possible to investigate interior space analysis to a more objective and scientific ways. The purpose of this study is to investigate Modern and Post-Modern interior - architectural style with quantitative analytical method. The subjective interior critique studied by intuitive research will be transferred to scientific way by using quantitative formula . Savoye Villa and Guardiola House were selected as study model, because each architectural works ware regarded as masterpieces of Modern and Post-Modern style. These two oppositional style model will be distinguished with mathematical quantity by calculating Iave , Hmax, and Redundancy formula.

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기존 교량구조물의 내진보강을 위한 우선순위 결정방법 (Damage Risk Based Approach for Retrofit Prioritization of Bridges)

  • 이상우;김상효;마호성
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2003년도 추계 학술발표회논문집
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    • pp.295-302
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    • 2003
  • A quantitative approach for the retrofit prioritization of bridges is developed based on the damage risk of seismic vulnerable components. In the developed approach, seismic damage risk is estimated in the probabilistic perspectives with an analytical bridge model, which can consider various phenomena found in the seismic behaviors of girder-type bridges and damage models of various vulnerable components. Based on the total cost due to failure of structural components, weighting factors are proposed. Finally, the ranking index and retrofit priority of bridges are estimated from the overall damage risk and weighting factors of bridges. As a result, the retrofit priority of four PSC girder bridges is evaluated by using the proposed approach. The vulnerable components in need of seismic retrofit are selected accordingly. From simulated results, the validity of the proposed approach is verified by comparison with the existing approach. In addition, the proposed approach is found to be appropriate in evaluating the priority of existing bridges.

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Saccadic 안구운동 해석에 대한 통계학적인 접근 (A Statistical Approach to Analysis of Saccadic Eye Movements)

  • Kim, Nam-Gyun;Kim, Bu-Gil
    • 대한의용생체공학회:의공학회지
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    • 제10권3호
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    • pp.289-292
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    • 1989
  • In this study we propose an approach based on statistical method which use the whole of saccades instead of using a few points of saccades in the quantitative analyse saccades. We computed statistical parameters such as mean velocity, quadratic mean velocity, standard duration, skewness of saccades velocity, flattness factor of saccades velocity, and mean delay by considering eye velocity as a probability density function. The results abtained are the following as ; This parameters showed the same trend like that of the main sequence. They were not biased by the systematic errors due to the arbitrary threshold. They were also less sensitive to noise, which was tested through the model simulation. So they are expected to provide a more comprehensive quantitative description of the dynamic properties of saccade in the diagnostic field.

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Wooden framed structures with semi-rigid connections: Quantitative approach focused on design needs

  • Santana, C.L.O.;Mascia, N.T.
    • Structural Engineering and Mechanics
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    • 제31권3호
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    • pp.315-331
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    • 2009
  • Mechanical connections are recognized as extremely important elements in the aspect of strength and structural safety. However, classical structural model does not consider the connection stiffness properties, and are based on models with pinned or rigid joints only. In fact, mechanical connections are deformable and behave not linearly, affecting the whole structure and inducing nonlinear behavior as well. The quantification of this effect, however, depends on the description of the working of the connectors and the wood response under embedment. The theoretical modeling of wood structures with semi-rigid connections involves not only the structural analysis, but also the modeling of both single and grouped moment resisting connectors and the study of the wood properties under embedment. The proposal of this paper is to approach these aspects, and to quantitatively study the influence of the moment resistant connection in wooden framed structures. Comparisons between rigid and semi-rigid connections and between linear and nonlinear analysis lead to quantitative results.

항공사 기내서비스 프로세스분석에 근거한 서비스품질 감사시스템개발에 관한 연구 (A Study for the Service Quality Audit System Development based on the Analysis of Airline Cabin Service Process)

  • 이지민;김연성
    • 품질경영학회지
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    • 제40권3호
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    • pp.406-414
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    • 2012
  • Purpose: In this study, we developed a service quality audit system through analyzing service processes of airlines' cabin service. Methods: Applying the qualitative approach to service processes analysis; 'service blueprint' methodology was developed, providing airlines a blueprint for cabin service and applying the quantitative service quality audit approach called 'walk-through audit', an audit methodology tailored to airline cabin service called PCPA (Passenger Cabin Patrol Audit) was developed. Results: This study tried to apply both the qualitative and the quantitative methodologies to develop service quality audit checklist and tried to develop details to systemize them into a new methodology. Conclusion: This study will be helpful for Airline services improvement by providing 'service quality audit model', so as to find out the problems and share those with the stakeholders.

단결정 철의 소성에 대한 멀티스케일 모델링 (Multi-scale Modeling of Plasticity for Single Crystal Iron)

  • 전종배;이병주;장영원
    • 소성∙가공
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    • 제21권6호
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    • pp.366-371
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    • 2012
  • Atomistic simulations have become useful tools for exploring new insights in materials science, but the length and time scale that can be handled with atomistic simulations are seriously limiting their practical applications. In order to make meaningful quantitative predictions, atomistic simulations are necessarily combined with higher-scale modeling. The present research is thus concerned with the development of a multi-scale model and its application to the prediction of the mechanical properties of body-centered cubic(BCC) iron with an emphasis on the coupling of atomistic molecular dynamics with meso-scale discrete dislocation dynamics modeling. In order to achieve predictive multi-scale simulations, it is necessary to properly incorporate atomistic details into the meso-scale approach. This challenge is handled with the proposed hierarchical information passing strategy from atomistic to meso-scale by obtaining material properties and dislocation mobility. Finally, this fundamental and physics-based meso-scale approach is employed for quantitative predictions of the mechanical response of single crystal iron.

스키마 개념을 도입한 사용자 계획수립의 용이도 평가 (Evaluation of Planning Transparence of User Interface Reflecting State Schemas)

  • 윤완철
    • 한국경영과학회지
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    • 제17권2호
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    • pp.45-54
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    • 1992
  • It become increasingly important to design user interface to carry low complexity. The cognitive limitations of users severely restrict utility of highly intelligent but complex modern systems. Since humans are known to use schemas to reduce cognitive complexity, imposing good consistency to an interface design that may help that user form useful schemas will provide powerful control over the complexity. This present a research effort to develop a quantitative method for evaluating interface complexity that the user would experience planning his or her course of action. Taking into account the user's potential schemas, a quantitative measure based on information theory was develped to assess the navigational complexity. This approach does not rely on the subjective judgment of the researcher as most schemes dealing with user schemas do. The proposed method may benefit the rapid prototyping approach to design a better user interface by allowing handy assessment of the design.

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정량적 리스크 평가를 기초로 한 경영관리 (Management Approach Based on Quantitative Risk Assessment)

  • 정원
    • 한국신뢰성학회지:신뢰성응용연구
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    • 제8권4호
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    • pp.167-179
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    • 2008
  • System risk is the totality of all safety risks to customers, employees, suppliers, and other third parties that arise due to system operations. To assess the risk of major hazards with the potential to cause fatality to the customers and other members of the public, quantitative risk assessment methodologies are used. This paper presents the general principles of risk based management approach to improve the safety of high risk systems such as aviation, railway, and nuclear power plants. For the suitable risk control arrangement, case studies of acceptable risk level, risk rating matrix, and safety management philosophy are presented.

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