• Title/Summary/Keyword: Patterns of failure

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A Study on Critical Success Factors for Enterprise Systems Implementation: A Failure Case Analysis Based on Process Theory (엔터프라이즈 시스템 구현의 핵심성공요소에 관한 연구: 프로세스이론을 기반으로 한 실패사례 분석)

  • Kim, Hee-Woong;Kwahk, Kee-Young
    • Journal of Information Technology Services
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    • v.6 no.3
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    • pp.251-272
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    • 2007
  • Although Enterprise Systems (ES) have promised major strategic benefits and process improvements from business and technology integration, their implementation has been plagued by a high failure rate and difficulty in realizing the promised benefits. For the purpose of understanding implementation failures, previous studies have focused on identifying critical success factors (CSFs) for information systems implementation. However, there has been little research on how these CSFs actually lead to successful results. In this study, based on process theory, we examined the process of ES implementation by explaining how the factors of ES implementation influence each other and how interaction among them produces results. Based on a failure case, we then developed a process model of ES implementation thus allowing us to explain the process of ES implementation. The proposed model facilitated an understanding of how repeating patterns of ES failure can be reversed. This model can be used for guiding new ES implementation projects.

Seismic performance of RC short columns with light transverse reinforcement

  • Tran, Cao Thanh Ngoc;Li, Bing
    • Structural Engineering and Mechanics
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    • v.67 no.1
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    • pp.93-104
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    • 2018
  • The seismic behavior of reinforced concrete (RC) short columns with limited transverse reinforcement is investigated in this paper through an experimental program. The experimental program consists of four small-scale RC columns with an aspect ratio of 1.7, which are tested to the axial failure stage. The cracking patterns, hysteretic responses, strains in reinforcing bars, displacement decomposition and cumulative energy dissipation of the tested specimens are reported in detail in the paper. The effects of column axial load are investigated to determine how this variable might influence the performance of the short columns with limited transverse reinforcement. Brittle shear failure was observed in all tested specimens. Beneficial and detrimental effects on the shear strength and drift ratio at axial failure of the test specimens due to the column axial load are found in the experimental program, respectively.

Estimation of a Bivariate Exponential Distribution with a Location Parameter

  • Hong, Yeon-Ung;Gwon, Yong-Man
    • Journal of the Korean Data and Information Science Society
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    • v.13 no.2
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    • pp.243-250
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    • 2002
  • This paper considers the problem of estimating parameters of the bivariate exponential distribution with a location parameter for a two-component shared parallel system using component data from system-level life test terminated at the time of the prespecified number of system failure. In the system-level life testing, there are three patterns of failure types ; 1) both component failed 2) both component censored 3) one is failed and the other is censored. In the third case, we assume that the failure time might be known or unknown. The maximum likelihood estimators are obtained for the case of known/unknown failure time when the other component is censored.

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Concepts on Deformation Dependent Strut-and-Tie Models (변형을 고려한 스트럿-타이 모델)

  • Hong, Sung-Gul;Jang, Sang-Ki
    • Proceedings of the Korea Concrete Institute Conference
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    • 2005.11a
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    • pp.209-212
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    • 2005
  • This paper presents, basic concepts on deformation models for D-regions critical to shear. Strut-and-tie models are used to construct for deformation estimation at yielding and ultimate deformation. A generic: strut-and-tie model is proposed to investigate deformation patterns and failure mode identification. Superposition of the basic models enables us to explain deformation limits of arch action and truss action. Displacement at yielding is assessed by consideration of deformation of reinforcing steel only while the ultimate displacement is calculated by limits of ultimate strain of concrete in compression and failure mechanisms.

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Bi-directional fault analysis of evaporator inspection system

  • Kang, Dae-Ki;Kang, Jeong-Jin
    • International journal of advanced smart convergence
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    • v.1 no.1
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    • pp.57-60
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    • 2012
  • In this paper, we have performed a safety analysis on an automotive evaporator inspection system. We performed the bi-directional analysis on the manufacturing line. Software Fault Tree Analysis (SFTA) as backward analysis and Software Failure Modes, Effects, & Criticality Analysis (SFMECA) as forward analysis are performed alternately to detect potential cause-to-effect relations. The analysis results indicate the possibility of searching and summarizing fault patterns for future reusability.

Crack pattern and failure mode prediction of SFRC corbels: Experimental and numerical study

  • Gulsan, Mehmet Eren;Cevik, Abdulkadir;Mohmmad, Sarwar Hasan
    • Computers and Concrete
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    • v.28 no.5
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    • pp.507-519
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    • 2021
  • In this study, a new procedure was proposed in order to predict the crack pattern and failure mode of steel fiber reinforced concrete (SFRC) corbels. Moreover, an experimental study was carried out in order to investigate the effect of several parameters, such as compressive strength, tensile strength, steel fiber ratio, shear span on the mechanical behavior of SFRC corbels in detail. Totally, 24 RC and SFRC corbels were prepared for the experimental study. Experimental results indicate that each investigated parameter has noticeable effect on the load capacity and failure mode of SFRC corbels. Moreover, finite element (FE) model of the tested corbels were prepared and efficiency of FE model was investigated for further studies. Comparison of FE and experimental results show that there is an acceptable fit between them regarding load capacity and crack patterns. Thereafter, parametric study was carried out via FE analyses in order to obtain a methodology for crack pattern and failure mode prediction of SFRC corbels. As a result of parametric studies, a new procedure was proposed as flowcharts in order to predict the failure mode of SFRC corbels for normal and high strength concrete class separately.

Theoretical Assessment of Limit Strengthening Ratio of Bridge Deck Based on the Failure Characteristic (교량 바닥판의 파괴형태를 고려한 임계보강재비의 이론적 산정)

  • 심종성;오홍섭;유재명
    • Journal of the Korea Concrete Institute
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    • v.14 no.1
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    • pp.110-117
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    • 2002
  • In a strengthened bridge deck which received increased service loads, failure patterns of bridge deck vary depending on deck thickness, compressive strength of concrete, yielding strength of reinforcement, reinforcement ratio and additional strengthening ratio. General failure pattern that is most commonly reported as punching shear failure after the main rebar yields, followed by yielding of distributing rebar. In this paper, by Proposing a limit to the amount of strengthening material, a brittle failure can be prevented and a ductile failure mode similar to that developed in unstrengthened deck is derived. In order to calculated the limit strengthening ratio, the yield line theory and previously proposed plastic punching shear model have been used

Prognostic factors, failure patterns and survival analysis in patients with resectable oral squamous cell carcinoma of the tongue

  • Sharma, Kanika;Ahlawat, Parveen;Gairola, Munish;Tandon, Sarthak;Sachdeva, Nishtha;Sharief, Muhammed Ismail
    • Radiation Oncology Journal
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    • v.37 no.2
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    • pp.73-81
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    • 2019
  • Purpose: There is sparse literature on treatment outcomes research on resectable oral tongue squamous cell carcinoma (OTSCC). The aim of this study was to measure the treatment outcomes, explore the failure patterns, and identify the potential clinicopathological prognostic factors affecting treatment outcomes for resectable OTSCC. Materials and Methods: It is a retrospective analysis of 202 patients with resectable OTSCC who underwent upfront primary surgical resection followed by adjuvant radiotherapy with or without concurrent chemotherapy if indicated. Results: The median follow-up was 35.2 months (range, 1.2 to 99.9 months). The median duration of locoregional control (LRC) was 84.9 months (95% confidence interval, 67.3-102.4). The 3- and 5-year LRC rate was 68.5% and 58.3%, respectively. Multivariate analysis showed that increasing pT stage, increasing pN stage, and the presence of extracapsular extension (ECE) were significantly associated with poorer LRC. The median duration of overall survival (OS) was not reached at the time of analysis. The 3- and 5-year OS rate was 70.5% and 66.6%, respectively. Multivariate analysis showed that increasing pT stage and the presence of ECE were significantly associated with a poorer OS. Conclusion: Locoregional failure remains the main cause of treatment failure in resectable OTSCC. There is scope to further improve prognosis considering modest LRC and OS. Pathological T-stage, N-stage, and ECE are strong prognostic factors. Further research is required to confirm whether adjuvant therapy adds to treatment outcomes in cases with lymphovascular invasion, perineural invasion, and depth of invasion, and help clinicians tailoring adjuvant therapy.

Characteristics of the Problem Solving Process of the Balancing Redox Equations by Senior and Science High School Students' Mental Capacity and Problem Solving Methdos (일반고와 과학고 학생들의 정신용량과 풀이 방법에 따른 산화 환원 반응식 완결 과정의 특성)

  • Kim, Chung-Ho;Lee, Sang-Gwon
    • Journal of the Korean Chemical Society
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    • v.46 no.4
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    • pp.353-363
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    • 2002
  • In this study, characteristics of the problem solving process of the balancing redox equations was ana-lyzed by mental capacity and problem solving methods, and the pertinent teaching and learning guidance for oxidation-reduction unit was suggested. Participants were 79 senior high school students and 57 science high school students. Tests were conducted to measure the mental capacity, the understanding of the oxidation-reduction concepts and the com-pletion of the balancing redox equations. The framework was made to find the patterns of failure and success. As the analysis of the influence on the performance of mental capacity,understanding of the oxidation-reduction concepts, and problem solving methods, students who had lower understanding of oxidation-reduction concepts selected the trial and error method, and their performance were influenced by mental capacity. The students that had higher understanding of the oxidation-reduction concepts had good performance by using oxidation number method regardless of their mental capacity. As the results of analysis for the patterns, the success patterns of solving the problems, those of mostly the sci-ence high school students, were the cases of using oxidation number method well and lessening problem solving steps. The patterns of failure in solving problems by using trial and error method showed that students had mistakes in cal-culating, errors in making unknown equations, no consideration for all variables, or stopped solving the complicated problems. The patterns of failure in solving problems by using oxidation number method showed that many students had wrong oxidation number or no consideration for mass and charge balance.

Experimental behavior and shear bearing capacity calculation of RC columns with a vertical splitting failure

  • Wang, Peng;Shi, Qing X.;Wang, Qiu W.;Tao, Yi
    • Earthquakes and Structures
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    • v.9 no.6
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    • pp.1233-1250
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    • 2015
  • The behavior of reinforced concrete (RC) columns made from high strength materials was investigated experimentally. Six high-strength concrete specimen columns (1:4 scale), which included three with high-strength transverse reinforcing bars and three with normal-strength transverse reinforcement, were tested under double curvature bending load. The effects of yielding strength and ratio of transverse reinforcement on the cracking patterns, hysteretic response, shear strength, ductility, strength reduction, energy dissipation and strain of reinforcement were studied. The test results indicated that all specimens failed in splitting failure, and specimens with high-strength transverse reinforcement exhibited better seismic performance than those with normal-strength transverse reinforcement. It also demonstrated that the strength of high-strength lateral reinforcing bars was fully utilized at the ultimate displacements. Shear strength formula of short concrete columns, which experienced a splitting failure, was proposed based on the Chinese concrete code. To enhance the applicability of the model, it was corroborated with 47 short concrete columns selected from the literature available. The results indicated that, the proposed method can give better predictions of shear strength for short columns that experienced a splitting failure than other shear strength models of ACI 318 and Chinese concrete codes.