• 한국건설관리학회논문집
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• 제6권1호
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• pp.195-204
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• 2005

건설실패정보는 건설실패를 야기한 업무 프로세스를 파악하고, 건설실패를 예방할 수 있는 향상된 프로세스를 제공하는 핵심 요인이 될 수 있다. 본 연구에서는 건설실패정보를 활용하여, 건설실패의 재발을 예방할 수 있는 건설 프로세스의 지속적 개선 모델의 개념적 틀을 제시하였다. 문헌연구를 통해 건설실패의 정의, 유형, 원인 및 교훈 등의 건설실패정보에 대한 개념을 정립하였다. 또한 건설실패정보에 프로세스 재설계 방법론 및 사례기반추론기법을 적용하여 프로세스 개선에의 적용가능성을 확인하였고, 사례기반추론기법의 주요 모듈인 사례검색, 사례색인 및 사례적응을 이용한 건설 프로세스의 지속적 개선 모델의 개념적 틀을 제시하였다.

• 한국건설관리학회논문집
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• 제25권4호
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• pp.66-81
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• 2024

Identifying the root causes of substandard construction projects is crucial considering the social and economic issues structural failures can cause. To date, the focus has predominantly been on identifying and penalizing the culprits rather than uncovering the fundamental reasons. Therefore, this study aims to identify various factors that contribute to failures in construction project quality management, including aspects of substandard construction projects, and determine the relationship between these factors and substandard construction projects. Through a literature review and case analysis, 61 influential factors were identified. A survey targeting participants including structural designers, architectural designers, construction companies, CM, and researchers was conducted to gauge the consensus on these factors. A regression analysis was performed based on data from 724 survey respondents. Ultimately, based on the 17 key influencing factors identified by the regression analysis, 9 preventive measures against substandard construction projects were proposed. This study is significant as it elucidates the reasons behind construction project quality management failures that lead to substandard construction projects and establishes a framework for developing practical solutions to real-world problems rather than theoretical or abstract ones.

• Structural Engineering and Mechanics
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• 제89권4호
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• pp.399-409
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• 2024

Assessment of existing concrete bridges is a challenge for owners. It has greater economic impact when compared to designing new bridges. When using conventional linear analyses, judgment of the engineer is required to understand the behavior of redundant structures after the first element in the structural system reaches its ultimate capacity. The alternative is to use a predictive tool such as advanced nonlinear finite element analyses (ANFEA) to assess the overall structural behavior. This paper proposes a new reliability framework for the assessment of existing bridge structures using ANFEA. A general framework defined in previous works, accounting for material uncertainties and concrete model performance, is adapted to the context of the assessment of existing bridges. A "shifted" reliability problem is defined under the assumption of quasi-deterministic dead load effects. The overall exercise is viewed as a progressive pushover analysis up to structural failure, where the actual safety index is compared at each event to a target reliability index.

• Industrial Engineering and Management Systems
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• 제13권1호
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• pp.87-100
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• 2014

Risk management is recognized as a significant element in Information Security Management while the failure mode and effects analysis (FMEA) is widely used in risk analysis in manufacturing industry. This paper aims to present the development work of the Information Security FMEA Circle (InfoSec FMEA Circle) which is used to support the risk management framework by modifying traditional FMEA methodologies. In order to demonstrate the "appropriateness" of the InfoSec FMEA Circle for the purposes of assessing information security, a case study at Hong Kong Science and Technology Parks Corporation (HKSTP) is employed. The "InfoSec FMEA Circle" is found to be an effective risk assessment methodology that has a significant contribution to providing a stepwise risk management implementation model for information security management.

• Steel and Composite Structures
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• 제1권4호
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• pp.411-426
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• 2001

This paper treats the failure analysis of prestressing steel wires with different kinds of localised damage in the form of a surface defect (crack or notch) or as a mechanical action (transverse loads). From the microscopical point of view, the micromechanisms of fracture are shear dimples (associated with localised plasticity) in the case of the transverse loads and cleavage-like (related to a weakest-link fracture micromechanism) in the case of cracked wires. In the notched geometries the microscopic modes of fracture range from the ductile micro-void coalescence to the brittle cleavage, depending on the stress triaxiality in the vicinity of the notch tip. From the macroscopical point of view, fracture criteria are proposed as design criteria in damage tolerance analyses. The transverse load situation is solved by using an upper bound theorem of limit analysis in plasticity. The case of the cracked wire may be treated using fracture criteria in the framework of linear elastic fracture mechanics on the basis of a previous finite element computation of the stress intensity factor in the cracked cylinder. Notched geometries require the use of elastic-plastic fracture mechanics and numerical analysis of the stress-strain state at the failure situation. A fracture criterion is formulated on the basis of the critical value of the effective or equivalent stress in the Von Mises sense.

• Computers and Concrete
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• 제29권1호
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• pp.1-14
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• 2022

Several aspects influence corrosive processes in reinforced concrete (RC) structures such as environmental conditions, structural geometry and mechanical properties. Since these aspects present large randomnesses, probabilistic models allow a more accurate description of the corrosive phenomena. Besides, the definition of limit states in the reliability assessment requires a proper mechanical model. In this context, this study proposes a straightforward methodology for the mechanical-probabilistic modelling of RC structures subjected to reinforcements' corrosion. An improved damage approach is proposed to define the limit states for the probabilistic modelling, considering three main degradation phenomena: concrete cracking, rebar yielding and rebar corrosion caused either by chloride or carbonation mechanisms. The stochastic analysis is evaluated by the Monte Carlo simulation method due to the computational efficiency of the Lumped Damage Model for Corrosion (LDMC). The proposed mechanical-probabilistic methodology is implemented in a computational framework and applied to the analysis of a simply supported RC beam and a 2D RC frame. Curves illustrate the probability of failure evolution over a service life of 50 years. Moreover, the proposed model allows drawing the probability of failure map and then identifying the critical failure path for progressive collapse analysis. Collapse path changes caused by the corrosion phenomena are observed.

• 한국의류학회지
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• 제35권6호
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• pp.700-711
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• 2011

The purposes of the study were to identify the online service attributes that contribute to online consumer experiences of satisfaction, service failure, and service recovery and to examine whether differences exist in these attributes between U.S. and Korea. E-A-S-QUAL provided a useful framework for the study. Focus group interviews and web surveys were conducted by utilizing college students in both countries. No significant cultural differences were found in online service dimensions of service satisfaction. Personalization was the most frequently mentioned online service dimension of service satisfaction both in the U.S. and Korea. The findings showed significant cultural differences in terms of online service dimensions responsible for service failure and recovery. For Korean consumers, merchandising was one of the key online service dimensions of service failure, while efficiency was the important service dimension resulting in service failure for the U.S. consumers. In addition, for U.S. consumers, efficiency and personalization were the two most frequently mentioned service dimension for service recovery, while Korean consumers put more importance on the contact and information dimensions for service recovery. This study provided a comprehensive list of online service attributes important to online apparel retailing.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.324-337
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• 2010

For the development of load and resistance factor design, reliability analysis is required to calibrate resistance factors in the framework of reliability theory. The distribution of measured-to-predicted pile resistance ratio was constructed based on only the results of load tests conducted to failure for the assessment of uncertainty regarding pile resistance and used in the conventional reliability analysis. In other words, successful pile load test (piles resisted twice their design loads without failure) results were discarded, and therefore, were not reflected in the reliability analysis. In this paper, a new systematic method based on Bayesian theory is used to update reliability index of driven steel pile piles by adding more pile load test results, even not conducted to failure, into the prior distribution of pile resistance ratio. Fifty seven static pile load tests performed to failure in Korea were compiled for the construction of prior distribution of pile resistance ratio. Reliability analyses were performed using the updated distribution of pile resistance ratio and the total load distribution using First-order Reliability Method (FORM). The challenge of this study is that the distribution updates of pile resistance ratio are possible using the load test results even not conducted to failure, and that Bayesian update are most effective when limited data are available for reliability analysis or resistance factors calibration.

• Nuclear Engineering and Technology
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• 제32권4호
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• pp.299-308
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• 2000

A safety assessment of reactor vessel lower head integrity under in-vessel vapor explosion loads has been performed. The core melt relocation parameters were chosen within the ranges of physically realizable bounds. The premixing and explosion calculations were performed using TRACER-II code. Using the calculated explosion pressures imposed on the lower head inner wall, strain calculations were peformed using ANSYS code. Then, the calculated strain results and the established failure criteria were used in determining the failure probability of the lower head, In the explosion analyses, it is shown that the explosion impulses are not altered significantly by the uncertain parameters of triggering location and time, fuel and vapor volume fractions in uniform premixture bounding calculations. Strain analyses show that the vapor explosion-induced lower head failure is not possible under the present framework of assessment. The result of static analysis using the conservative explosion-end pressure of 50 MPa also supports the conclusion. It is recommended, however, that an assessment of fracture mechanics for preexisting cracks be also considered to obtain a more concrete conclusion.

• 융합경영연구
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• 제8권1호
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• pp.12-19
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• 2020

Purpose - Strategic causes for the failure include unrealistic growth, overexpansion, unfamiliar new markets, volume obsession, unrealistic promises and poor project selection. Organizational causes are insufficient capital and profits, lack of business knowledge, poor financial management, poor sales skills, inadequate marketing, poor leadership, poor leadership transfer, project losses, poor field performance and owner bankruptcy. Uncontrollable causes include industry and economic weakness and banking and surety changes. While helpful, the list provides insufficient clarity regarding the causal roots of failure. Research design, data and methodology - The research framework to organize the information involved with many of the recent and large failures in the industry. Results - This research then identified five dominant root causes - excessive egoism, poor strategic leadership, too much change, loss of discipline and inadequate capitalization. Conclusion - Finally, additional input from external forces may accelerate the firm's pace to failure. It is important on the development of diagnostic tools that are based on this model and that will provide new ways to assess a conglomerate's level of risk for incurring a financial crisis.