• Title/Summary/Keyword: Multiple Case Study

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A Control Chart for Gamma Distribution using Multiple Dependent State Sampling

  • Aslam, Muhammad;Arif, Osama-H.;Jun, Chi-Hyuck
    • Industrial Engineering and Management Systems
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    • v.16 no.1
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    • pp.109-117
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    • 2017
  • In this article, a control chart based on multiple dependent (or deferred) state sampling for the gamma distributed quality characteristic is proposed using the gamma to normal transformation. The proposed control chart has two pairs of control limits, which can be determined by considering the in-control average run length (ARL). The shift in the scale parameter of a gamma distribution is considered and the out-of-control ARL is evaluated. The performance of the proposed chart has been shown for different levels of the parameters of the proposed control chart. It is also shown that the proposed chart is better than the Shewhart chart in terms of ARLs. A case study with a real data has been included for the practical usage of the proposed scheme.

Bayesian multiple comparisons in Freund's bivariate exponential populations with type I censored data

  • Cho, Jang-Sik
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.3
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    • pp.569-574
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    • 2010
  • We consider two components system which have Freund's bivariate exponential model. In this case, Bayesian multiple comparisons procedure for failure rates is sug-gested in K Freund's bivariate exponential populations. Here we assume that the com-ponents enter the study at random over time and the analysis is carried out at some prespeci ed time. We derive fractional Bayes factor for all comparisons under non- informative priors for the parameters and calculate the posterior probabilities for all hypotheses. And we select a hypotheses which has the highest posterior probability as best model. Finally, we give a numerical examples to illustrate our procedure.

Investigation of possible causes of sinkhole incident at the Zonguldak Coal Basin, Turkey

  • Genis, Melih;Akcin, Hakan;Aydan, Omer;Bacak, Gurkan
    • Geomechanics and Engineering
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    • v.16 no.2
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    • pp.177-185
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    • 2018
  • The subsidence mechanism of ground surface is a complex phenomenon when multiple seam coal mining operations are carried out. Particularly, the coal mining beneath karstic formations causes a very special form of subsidence. The subsidence causes elasto-plastic deformation of the karstic layers and the collapse of cavities leads to dolinization and/or sinkhole formation. In this study, a sinkhole with a depth of 90 m and a width of 25 m formed in Gelik district within the coal-basin of Zonguldak (NW, Turkey) induced by multiple seam coal mining operations in the past has been presented as a case-history together with two-dimensional numerical simulations and InSAR monitoring. The computational results proved that the sinkhole was formed as a result of severe yielding in the close vicinity of the faults in contact with karstic formation due to multiple seam longwall mining at different levels.

A DECISION SUPPORT MODEL FOR PROCUREMENT OF REUSABLE MATERIALS IN MULTIPLE PROJECT MANAGEMENT

  • Ju-Yeoun Han;Dong-Woo Shin ;Kyung-Rai Kim ;Sang-yoon Chin;Hee-Sung Cha
    • International conference on construction engineering and project management
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    • 2005.10a
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    • pp.1100-1105
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    • 2005
  • To compete with large construction companies whose dominance in market share is deepening recently, the needs for improving field production system of mid-size construction companies have increased rapidly. The development of an adequate model that focuses on the organizational size and work process of the mid-size construction companies are needed to increase productivity through the informatization in the construction industry[0]. The authors of this study used case studies on the problems of the mid-size construction companies in procuring work and presented a method to solve such problems so that the managers in head office of those mid-size construction companies can effecitively deal with multiple sites[0].

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A Study on Ways to Improve Safety Management through Analysis of Fire Cases in Multiple-user Buildings (다중이용업소의 화재사례 분석을 통한 안전관리 개선방안 연구)

  • Lee, Jae Wook
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.3
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    • pp.191-201
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    • 2022
  • In this study, we are going to derive problems for fire and safety management in multiple-user Buildings and suggest improvement measures to prevent recurrence through analysis of legal operation status for safety management of multiple-user Buildings and case studies of large-scale fires in multiple-user Buildings. For this study, first, the current state of the industry and fire occurrence status were investigated through theoretical considerations of the multi-use industry, and then the previous research on the multi-use industry was analyzed. and by analyzing the legal and institutional status of multiple-user Buildings, problems were derived through cases such as the Jecheon fire in Chungcheongbuk-do, the Inhyeon-dong fire in Incheon, and the Songpa-gu fire in Seoul. As a result, first, the necessity of strengthening the initial fire response capability. Second, thorough maintenance and management of emergency exits. Third, the need for rational regulation of upholstery. Fourth, reinforcement of fire safety education and training. Fifth, strengthening of installation standards for firefighting and safety facilities. Sixth, we derive the result that it is necessary to raise awareness about safety management, compare and analyze it with legal and institutional contents, and suggest solutions accordingly. When looking at the causes of fires in multi-use buildings, building owners, business owners, and employees think that there is no possibility of a fire occurring in their business premises, so there is a lack of awareness. It is necessary to raise awareness through education and publicity of firefighters and related administrative agencies.

Estimation of active multiple tuned mass dampers for asymmetric structures

  • Li, Chunxiang;Xiong, Xueyu
    • Structural Engineering and Mechanics
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    • v.29 no.5
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    • pp.505-530
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    • 2008
  • This paper proposes the application of active multiple tuned mass dampers (AMTMD) for translational and torsional response control of a simplified two-degree-of-freedom (2DOF) structure, able to represent the dynamic characteristics of general asymmetric structures, under the ground acceleration. This 2DOF structure is a generalized 2DOF system of an asymmetric structure with predominant translational and torsional responses under earthquake excitations using the mode reduced-order method. Depending on the ratio of the torsional to the translational eigenfrequency, i.e. the torsional to translational frequency ratio (TTFR), of asymmetric structures, the following three cases can be distinguished: (1) torsionally flexible structures (TTFR < 1.0), (2) torsionally intermediate stiff structures (TTFR = 1.0), and (3) torsionally stiff structures (TTFR > 1.0). The even distribution of the AMTMD within the whole width and half width of the asymmetric structure, thus leading to three cases of installing the AMTMD (referred to as the AMTMD of case 1, AMTMD of case 2, AMTMD of case 3, respectively), is taken into account. In the present study, the criterion for searching the optimum parameters of the AMTMD is defined as the minimization of the minimum values of the maximum translational and torsional displacement dynamic magnification factors (DMF) of an asymmetric structure with the AMTMD. The criterion used for assessing the effectiveness of the AMTMD is selected as the ratio of the minimization of the minimum values of the maximum translational and torsional displacement DMF of the asymmetric structure with the AMTMD to the maximum translational and torsional displacement DMF of the asymmetric structure without the AMTMD. By resorting to these two criteria, a careful examination of the effects of the normalized eccentricity ratio (NER) on the effectiveness and robustness of the AMTMD are carried out in the mitigation of both the translational and torsional responses of the asymmetric structure. Likewise, the effectiveness of a single ATMD with the optimum positions is presented and compared with that of the AMTMD.

Risk Factors for Malassezia pachydermatis-associated Dermatitis in dogs: a Case-control Study (개에서 Malassezia pachydermatis에 의한 피부염의 위험요인에 관한 Case-control 연구)

  • Son-il Pak;Hwa-young Youn
    • Journal of Veterinary Clinics
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    • v.16 no.1
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    • pp.80-85
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    • 1999
  • Malassezia(Pityrosoprum) pachydermatis에 의한 피부염의 위험요인을 파악하고자 1997년 1월에서 1998년 12월까지 서울대학교 수의과대학 부속동물병원에 내원하여 본 질환으로 진단된 29두와 동일한 기간 동안 피부과 검사에서 임상적으로 건강한 개로 확인된 97 두의 대조군을 대상으로 분석하였다. 각 설명변수에 대한 교차비(odds ratio, OR)와 신뢰구간(confidence interval, CI)은 변수보정법을 사용하여 계산하였다. 다른 공변수를 보정한 상태에서 다중 로지스틱 회귀분석(multiple logistic regression analysis)을 시행한 결과 피부병기왕력(p=0.0059; OR, 4.44; CI, 1.5∼12.8)과 비만(p=0.0013; OR, 5.38; CI, 1.9∼14.9)은 유의한 위험요인으로 나타났다. 단변량 분석(univariate analysis)에서 주 사료로 고기를 섭취하는 경우 피부염의 위험이 높은 변수로 작용하였지만(p=0.0398; OR, 6.38; CI, 1.1∼37.3) 다른 공변수를 보정한 분석에서는 유의하지 않은 것으로 나타났다. 성별, 품종, 및 예방접종은 위험요인으로 작용하지 않았다.

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The Study for Development of Damper Case Production Technique using Incremental Forming (Incremental Forming 기술을 적용한 Damper Case 생산 기술 개발에 관한 연구)

  • Park, Jeong-Ho;Lee, Tae-Won;Jeong, Young-Duk
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.5
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    • pp.72-78
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    • 2011
  • Currently, for the damper case, the material produced by cast/forge welding is mechanically processed and then the final product is mass-produced. By cutting the cast/forge welded material, the issues of excessive cutting time, multiple process production, and a large amount of chips (40% loss from the original material) arise, causing increased production cost and reduced profitability. Thus, in this study, the incremental forming technology which generates no chips was applied in production. Analysis was excuted for 1st and 2nd works by change of tool diameter and working tool. For this, 3D molding and analysis were executed, which was applied to the processing the result, successful processing could be achieved through a few trials of molding processing according to tool forming and rotation counts.

Department of Statistics, Chonnam National University (임상시험을 위한 Case Report Form의 설계)

  • Park, Eun-Sik
    • Korean Journal of Clinical Pharmacy
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    • v.16 no.1
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    • pp.40-45
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    • 2006
  • In clinical trials, it is important to have well designed case report forms (CRF) in order to obtain good quality of data. If CRF design at the first stage of your study goes wrong, after all efforts have been made, you may find practical difficulties in data analysis at the final stage of your study because of incomplete or wrong information. In this paper, the following rules fundamental to CRF design are introduced: rules in general, rules of format or style, categorized responses, forms with multiple records per subject, and international studies. Investigators are well aware of research goals, however sometimes they do not know how to express it on CRF. If they understand the rules fundamental to CRF design, time for CRF development will be saved and CRF completeness will be enhanced.

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An Application of Case-Based Reasoning in Forecasting a Successful Implementation of Enterprise Resource Planning Systems : Focus on Small and Medium sized Enterprises Implementing ERP (성공적인 ERP 시스템 구축 예측을 위한 사례기반추론 응용 : ERP 시스템을 구현한 중소기업을 중심으로)

  • Lim Se-Hun
    • Journal of Information Technology Applications and Management
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    • v.13 no.1
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    • pp.77-94
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    • 2006
  • Case-based Reasoning (CBR) is widely used in business and industry prediction. It is suitable to solve complex and unstructured business problems. Recently, the prediction accuracy of CBR has been enhanced by not only various machine learning algorithms such as genetic algorithms, relative weighting of Artificial Neural Network (ANN) input variable but also data mining technique such as feature selection, feature weighting, feature transformation, and instance selection As a result, CBR is even more widely used today in business area. In this study, we investigated the usefulness of the CBR method in forecasting success in implementing ERP systems. We used a CBR method based on the feature weighting technique to compare the performance of three different models : MDA (Multiple Discriminant Analysis), GECBR (GEneral CBR), FWCBR (CBR with Feature Weighting supported by Analytic Hierarchy Process). The study suggests that the FWCBR approach is a promising method for forecasting of successful ERP implementation in Small and Medium sized Enterprises.

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