• Title/Summary/Keyword: academic failure

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Seismic investigation of cyclic pushover method for regular reinforced concrete bridge

  • Shafigh, Afshin;Ahmadi, Hamid Reza;Bayat, Mahmoud
    • Structural Engineering and Mechanics
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    • v.78 no.1
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    • pp.41-52
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    • 2021
  • Inelastic static pushover analysis has been used in the academic-research widely for seismic analysis of structures. Nowadays, the variety pushover analysis methods have been developed, including Modal pushover, Adaptive pushover, and Cyclic pushover, in which some weaknesses of the conventional pushover method have been rectified. In the conventional pushover analysis method, the effects of cumulative growth of cracks are not considered on the reduction of strength and stiffness of RC members that occur during earthquake or cyclic loading. Therefore, the Cyclic Pushover Analysis Method (CPA) has been proposed. This method is a powerful technique for seismic evaluation of regular reinforced concrete buildings in which the first mode of them is dominant. Since the bridges have different structures than buildings, their results cannot necessarily be attributed to bridges, and more research is needed. In this study, a cyclic pushover analysis with four loading protocols (suggested by valid references) by the Opensees software was conducted for seismic evaluation of two regular reinforce concrete bridges. The modeling method was validated with the comparison of the analytical and experimental results under both cyclic and dynamic loading. The failure mode of the piers was considered in two-mode of flexural failure and also a flexural-shear failure. Along with the cyclic analysis, conventional analysis has been studied. Also, the nonlinear incremental dynamic analysis (IDA) method has been used to examine and compare the results of pushover analyses. The time history of 20 far-field earthquake records was used to conduct IDA. After analysis, the base shear vs. displacement in the middle of the deck was drawn. The obtained results show that the cyclic pushover analysis method is able to evaluate an accurate seismic behavior of the reinforced concrete piers of the bridges. Based on the results, the cyclic pushover has proper convergence with IDA. Its accuracy was much higher than the conventional pushover, in which the bridge piers failed in flexural-shear mode. But, in the flexural failure mode, the results of each two pushover methods were close approximately. Besides, the cyclic pushover method with ACI loading protocol, and ATC-24 loading protocol, can provided more accurate results for evaluating the seismic investigation of the bridges, specially if the bridge piers are failed in flexural-shear failure mode.

Learning through Partnerships: Acquirer Firm's Experiences, Deal Partner's Characteristics and the Failure of Cross Border M&A (파트너십을 통합 학습: 인수기업의 경험, 거래 참여 파트너 기업의 특성 그리고 국경 간 M&A 실패)

  • Han, Byoung-Sop;Park, Eun-Kyoung
    • Korea Trade Review
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    • v.41 no.2
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    • pp.61-96
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    • 2016
  • This study investigates the effects of M&A experience of Chinese firms and characteristics of deal partners in cross border M&A deal failures. 1,610 firms that participated in 1,558 cross border M&As from 2000 to November 2015 are used as samples. The dependent variable is the M&A transaction failures, which were cases of deal pending or withdrawal of Chinese firms. Major independent variables are the nationality diversity of transaction partner firm, the partner firm belonging to a developed country, domestic M&A experience of the Chinese firms, M&A experience in a particular target country, etc. After conducting a probit model analysis, we find that deal partner firm's nationality diversity increases the failure rate of M&A. While prior domestic M&A experience in China has no influence on deal failure, prior M&A experience of Chinese and focal firms in a particular country have a negative effect on the probability of deal failure. This study has academic implication on figuring out why firms are likely to fail in the process of strategic activities based on the inter-organizational learning through partnerships perspective.

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Antecedents and the Moderating Effect of Value Consciousness on Customer Complaints in the Social Commerce Industry

  • Lee, Hae-Young;Reid, Earl;Kim, Woo-Gon
    • Culinary science and hospitality research
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    • v.22 no.6
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    • pp.98-104
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    • 2016
  • In comparison to the rapid rise in the number of restaurant daily deal service consumer complaints, relatively little attention has been directed at the features of deal consumers' complaint behaviors in academic research. In order to address this gap, this study examined the characteristics of complaint behaviors of consumers who purchase restaurant deals with a focus on three potential determinants (likelihood of success with the complaint, attitude toward complaining, and severity of the failure). Results indicated that the three proposed determinants emerged as critical factors that influence deal consumers to exhibit different complaint reactions to dissatisfactory experiences. Furthermore, it was discovered that the hypothesized relationships were moderated by value consciousness, in which high value-conscious deal consumers exhibited a higher complaint inclination than low-value conscious deal consumers.

Reliability analysis of latticed steel towers against wind induced displacement

  • Khan, M.A.;Siddiqui, N.A.;Abbas, H.
    • Steel and Composite Structures
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    • v.4 no.1
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    • pp.9-21
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    • 2004
  • The present study aims at the reliability analysis of steel towers against the limit state of deflection. For this purpose tip deflection of the tower has been obtained after carrying out the dynamic analysis of the tower using modal method. This tip deflection is employed for subsequent reliability analysis. A limit state function based on serviceability criterion of deflection is derived in terms of random variables. A complete procedure of reliability computation is then presented. To study the influence of various random variables on tower reliability, sensitivity analysis has been carried out. Design points, important for probabilistic design of towers, are also located on the failure surface. Some parametric studies have also been included to obtain the results of academic and field interest.

Posterior and Multidirectional Instability

  • Kim, Seung-Ho
    • The Academic Congress of Korean Shoulder and Elbow Society
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    • 2005.11a
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    • pp.78-93
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    • 2005
  • The posterior and multidirectional instability of the shoulder is a complex problem in terms of diagnosis and treatment. Increased joint volume by redundant capsular ligament has been regarded as a major pathogenesis of the posterior and multidirectional instability. Distinct from multidirectional hyperlaxity, multidirectional instability has symptoms related with increased translations in more than one direction. Recent report that shoulder symptom originates from labral lesion which was created by excessive rim-loading of the humeral head on the posteroinferior glenoid labrum during repetitive subluxation helps us to understand the pathogenesis of such instability. Painful jerk and Kim tests indicate labral lesion in the multidirectionally loose shoulder, suggesting multidirectional instability. Also, painful jerk test is a prognostic sign of failure of nonoperative treatment. The labral lesion can be an incomplete tear or a concealed lesion which often has been underestimated. Operative treatment is indicated when nonoperative treatment has failed. Arthroscopic capsulolabroplasty is a reliable procedure, which not only provides capsular balance, but also restores the labral height.

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A case study about the personnel management policy of Bachae co., Ltd. ((주)바체의 인사관리 정책 사례연구)

  • Hwang, Kyoo-Il
    • Management & Information Systems Review
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    • v.20
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    • pp.1-16
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    • 2007
  • This research is a case study about the personnel management policy of Bachae co., Ltd. Bachae Co., Ltd. suggests as a successful model that by implementing the pro-active personnel management strategy eliminated the seniority, age-limit, academic snobbism, the qualities critical for managerial success are leadership, motivation, decisiveness, flexibility. It gives a solution especially to medium-sized companies suffering the manpower shortage, that the adequate motivation through strong leadership to employee results in not only job satisfaction but also organization absorption. The fact that company care about even the failure staying at their jobs longer without hurting their self pride to be loyal employee is a very demonstrative and great method which motivates middle & midium size of companies how to manage and utilize the human resources.

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Safety Assessment for Hydrogen Gas Filling Facilities(One-Bank) (One-Bank 방식의 수소충전장치에 대한 정성적 안전성 평가)

  • Rhie, Kwang-Won;Kim, Tae-Hun
    • Journal of the Korea Safety Management & Science
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    • v.14 no.1
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    • pp.95-100
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    • 2012
  • This study is about the qualitative safety assessment for hydrogen gas filling facilities in Korea operating with one-bank type. The purpose of this safety assessment is about the development of components for design, fabrication, assembly, operability of dispenser and systems of the safety. For the qualitative safety assessment method, the study used FMEA(failure mode & effect analysis) and HAZOP(hazard & operability). This study evaluated the safety through FMEA and HAZOP then by referring to P&ID and PFD of hydrogen dispenser, thereby examining the dangerousness of the equipments, defects of the structure and problems of the operation.

A substructure formulation for the earthquake -induced nonlinear structural pounding problem

  • Shi, Jianye;Bamer, Franz;Markert, Bernd
    • Earthquakes and Structures
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    • v.17 no.1
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    • pp.101-113
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    • 2019
  • Earthquake-induced pounding is one of the major reasons for structural failure in earthquake prone cities. An accurate description of the pounding phenomenon of two buildings requires the consideration of systems with a large number of degrees of freedom including adequate contact impact formulations. In this paper, firstly, a node to surface formulation for the realization of state-of-the-art pounding models for structural beam elements is presented. Secondly, a hierarchical substructure technique is introduced, which is adapted to the structural pounding problem. The numerical accuracy and efficiency of the method, especially for the contact forces, are verified on an academic example, applying four different impact elements. Error estimations are carried out and compared with the classical modal truncation method. It is demonstrated that the hierarchical substructure method is indeed able to significantly speed up the numeric integration procedure by preserving a required level of accuracy.

The Effects of Group Composition of Self-Regulation on Project-based Group Performance

  • LEE, Hyeon Woo
    • Educational Technology International
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    • v.11 no.2
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    • pp.105-121
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    • 2010
  • Collaborative learning encourages the use of high-level cognitive strategies, critical thinking, and interpersonal relationships. Despite these advantages, most instructors reveal the difficulties of using project-based collaborative learning; a common problem is the failure of the group to work effectively together. Thus, this study attempted to provide practical advice on group composition with self-regulation. In a college course, 31 groups with 129 students were asked to discuss and prepare the final presentation material and present it together as a collaborative work. All students' self-regulation skills were measured at the beginning of the semester, and the collective self-regulation was computed as an average of the individual scores of each group. The results of regression analysis indicate that the group's collective self-regulation shows a highly significant positive effect on group performance and satisfaction, as self-regulation predicts individual academic performance. The results also show that there is a significant positive relationship between students' self-regulation and participation in group work.

Predictors of Deviant Self-Concept in Adolescence and Gender Differences: Applying a Latent-State Trait Autoregressive Model (청소년기 일탈적 자아개념의 예측 요인과 성별 차이 : 잠재 상태-특성 자기회귀 모델 (latent state-trait autoregressive model)의 적용)

  • Lee, Eunju;Chung, Ick-Joong
    • Korean Journal of Social Welfare Studies
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    • v.43 no.1
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    • pp.5-29
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    • 2012
  • The present study was to explore what makes adolescents think of themselves as troublemakers even without conduct problems. It was expected that the failure to attain socio-developmental milestones(e.g., healthy relationships with others, academic achievement) would lead to form trait aspect of deviant self-concept. A latent state-trait autoregressive modeling was used to analyze five annual waves of data from 3,449 adolescents taken from the Korean Youth Panel Study. We decomposed trait and state aspect of deviant self-concept and identified significant predictors of trait-like deviant self-concept, while additionally testing for gender differences. Our results showed that conduct problems had greater effect on deviant self-concept among girls compared with boys. Conduct problem was most predictive of deviant self-concept, and yet both poor peer-relations and school failures predisposed adolescents to have deviant self-concept. Low academic achievement conferred risk for trait aspects of deviant self-concept with no gender difference, whereas poor peer relation was more predictive among girls. It highlights the cultural value system underlying self-concept and how and why adolescents think of themselves as troublemakers.