• 한국IT서비스학회지
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• 제15권4호
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• pp.153-174
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• 2016

On account of multiple causes, including prolonged global economic crisis, addressing environmental pollution and the advent of hyper-connected society, a new paradigm called 'sharing economy' has rapidly emerged. Many startups have attempted to build promising business model based on the sharing economy concept. Nevertheless, successful cases are still very rare in the global level, except for Uber and Airbnb cases. Therefore, this study analyzes necessary causes and sufficient causes for successful settlements in the market through a comparative case analysis on digital matching firms in the sharing economy businesses. For the case study, we compare five successful cases (Uber, Airbnb, Kickstarter, TaskRabbit and DogVacay), three failure cases (Homejoy, Ridejoy and Tuterspree) and a platform cooperativism case (Juno) in accordance with six value attributes of business model including value proposition, market segment, value chain, cost structure and profit potential, value network and competitive strategy. We apply Boolean method to support controlled comparison and eliminate unnecessary attributes. The Boolean analysis result shows that value proposition, cost structure and profit potential, value network and competitive strategy are the essential attributes. Furthermore, the result indicates that each attribute is a necessary condition, where all four conditions should be met simultaneously in order to be successful. With this result, we discuss essential consideration for those who are planning startup based on the sharing economy business model.

• 복식
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• 제59권8호
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• pp.26-36
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• 2009

The aim of this study is to be the fundamental study for virtual clothing system of the future through a comparative analysis of the difference between a virtual frill skirt and a real frill skirt using a 3-dimensional Apparel cad system. Satin was selected as a comparative fabric of the real skirt and virtual skirt. And compared skirts are frilled 1.5widths, 2widths, and 2.5widths. In case of 1.5widths frilled, the real skirts and virtual skirts showed no significant difference except in shirring frill expression. However, in case of 2widths frilled, and 2.5widths frilled skirts, significant differences in the extent of frill flattening, the sectional diagram of the bottom hem, and the skirt shape. The virtual skirt showed that as its multiple proportion of frill increased, the sidelines of the skirt drooped and excessively extended, and collision detection that the belt was twisted and torn apart arose. Furthermore, not only the frill but also the shape of the skirt was transformed, and the bottom hems were widened back and forth, and the sectional diagram of the bottom hems were transformed into rounded shapes.

• 품질경영학회지
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• 제26권2호
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• pp.27-38
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• 1998

Consider a life testing experiment in which multiple two-component shared parallel systems are put on test, and the test is terminated at a specified number of system failures. The bivariate data obtained from such a system-level life testing can be classified into three classes: 1) the case of failed two components with known failure times, 2) the case of censored two components, and 3) the case of one censored component and the other failed component of which the failure time might be known or unknown. Under this censoring scheme and the assumption of Freund's bivariate exponential life distribution, the maximum likelihood estimators are obtained. Results of comparative studies based on Monte Carlo simulation are presented.

• 디지털융복합연구
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• 제19권11호
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• pp.215-224
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• 2021

디지털 기술을 활용하여 가상 공간과 현실 공간의 결합을 통해 비즈니스 가치를 증대시키려는 목적으로 메타버스를 활용하려는 이해관계자의 관심이 높아지고 있다. 본 연구는 메타버스의 기본 개념을 정립한 2006년 메타버스 로드맵과 디지털 전환 이론, 그리고 비즈니스 모델에 관한 이론을 이론적 준거로 하여 메타버스의 비즈니스 활용 가치에 관한 시사점을 얻고자 수행되었다. 구체적으로 2000년부터 2020년에 이르는 세 가지 메타버스 서비스를 다중 사례 연구법을 적용하여 분석하였다. 분석 결과 비즈니스 차원에서 보면 각각의 사례는 게임과 소셜 네트워크 서비스 그리고 협업 커뮤니케이션 플랫폼의 목적에 따라 다른 형태의 메타버스 구조를 선별적으로 받아들이고 있다. 디지털 전환 측면에서는 메타버스 기술을 활용하여 차별적인 경쟁 우위를 획득하기 위한 구조적 변화를 시도하였다는 점이 발견되었으나 비즈니스 모델 평가 측면에서 볼 때 이해관계자 신뢰성 측면에서 각 사례의 약점이 부각되었다. 본 연구를 통해 사용자의 필요와 수용 가능성에 따라 메타버스로의 디지털 전환 양상은 달라질 수 있으며 재무적 안정성과 이해관계자 신뢰성 측면에서 메타버스는 고도의 개방성을 유지할 필요가 있다는 점을 알 수 있었다.

• 가정과삶의질연구
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• 제31권5호
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• pp.47-63
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• 2013

This study deals with a counseling case in which a mother requested counseling due to the problems of her daughter, who suffers from multiple tic disorder. The participants of this study included five family members (grandmother, father, mother and two female children) and a total of 23 sessions were held from September 2006 to December 2007. Additional counseling ($24^{th}$ counseling session) was conducted on April 1st, 2009. The data was based on recorded transcripts and notes from 24 family therapy sessions. The study used a constant comparative analysis, which uses matrix and network display as an analysis method suggested by Miles&Huberman(1994). The characteristics of the family of origin and the indifference of the husband had caused the wife stress. The couple had frequent conflicts due to dysfunctional communication methods, a clash of values, sexual dissatisfaction, and a lack of communication. This marital conflict became the primary factor of the daughter's multiple tic disorder. Intervention of the family therapist resulted in the setting of treatment goals based on MRI's communication theory and Bowen's family systems theory in order to solve the problem of the daughter's multiple tic disorder. Also, the therapist's intervention techniques included exploring experiences with the family of origin, shedding light on the multigenerational transmission process, exploring dysfunctional attempts at solutions, the therapist's self-disclosure, providing similar cases, dealing with resistance, and suggesting a new communication method. To solve the problem, the therapist helped the family separate the daughter spatially from her parents. Therefore, the therapist's intervention helped reduce the daughter's tics and improve relationships among the family.

• Korean Journal of Hydrosciences
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• 제4권
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• pp.65-79
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• 1993

Selection of the best operating rule among a set of alternatives for a multipurpose reservoir system operation requires to evaluate many minor criteria in addition to the major objectives assessed to the system. These problems are sufficiently complex and difficult that they are beyond heuristic decision rules and experiences in case several noncommensurable multiple criteria are included in the evaluation. With the assistance of multicriterion decision analysis techniques, it is possible to select the best one among various alternatives by systematically comparing and ranking the alternatives with respect to the criteria of choice. Evaluation criteria for multipurpose reservoir system operating rules were identified and defined, and the multicriterion decision analysis techniques were applied to evaluate the four existing operating rules of the Chungju multipurpose project according to the identified nine multiple criteria. The application results show that the methodology is very efficient to select the best operation alternative among a finite number of operating rules with many evaluation criteria for a large-scale reservoir system operation.

• 보건행정학회지
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• 제25권4호
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• pp.333-342
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• 2015

Background: The purposes of this study is to analysis the differences of the job satisfaction between regular and non-regular workers in hospitals. Methods: The samples used for data analysis are 632 workers of 6 hospitals using a standardized questionnaires in B, C, D, and G provinces. In research methodology, all the data were analyzed with descriptive statistics, t-test, Pearson's correlation, and multiple linear regression analysis. Results: In case of regular workers, communication, working conditions and employee benefit, and education were found to have a significant positive (+) effect on job satisfaction. In case of non-regular workers, empowerment, reward systems, communication, working conditions, and employee benefit had a significant positive (+) effect on job satisfaction. Conclusion: These results showed that hospitals needed to reinforce communication, working conditions and employee benefit to regular and non-regular workers in order to improve job satisfaction. Especially, more empowerment, working conditions, and employee benefit should be given to non-regular workers.

• Nuclear Engineering and Technology
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• 제53권10호
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• pp.3236-3246
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• 2021

Lessons learned from the Fukushima Daiichi nuclear power plant accident directed that multiple failures should be considered more seriously rather than single failure in the licensing bases and safety cases because attempts to take accident management measures could be unsuccessful under the high radiation environment aggravated by multiple failures, such as complete loss of electric power, uncontrollable loss of coolant inventory, failure of essential safety function recovery. In the case of the complete loss of electric power called station blackout (SBO), if there is no mitigation action for recovering safety functions, the reactor core would be overheated, and severe fuel damage could be anticipated due to the failure of the active heat sink. In such a transient condition at CANDU-6 plants, the seal failure of the primary heat transport (PHT) pumps can facilitate a consequent increase in the fuel sheath temperature and eventually lead to degradation of the fuel integrity. Therefore, it is necessary to specify the regulatory guidelines for multiple failures on a licensing basis so that licensees should prepare the accident management measures to prevent or mitigate accident conditions. In order to explore the efficiency of implementing accident management strategies for CANDU-6 plants, this study proposed a realistic accident analysis approach on the SBO transient with multiple-failure sequences such as seal failure of PHT pumps without operator's recovery actions. In this regard, a comparative study for two PHT pump seal failure modes with and without coolant seal leakage was conducted using a best-estimate code to precisely investigate the behaviors of thermal-hydraulic parameters during transient conditions. Moreover, a sensitivity analysis for different PHT pump seal leakage rates was also carried out to examine the effect of leakage rate on the system responses. This study is expected to provide the technical bases to the accident management strategy for unmitigated transient conditions with multiple failures.

• Advances in Computational Design
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• 제3권4호
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• pp.385-404
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• 2018

The study investigated an area of sustainable structural design that is often overlooked in practical engineering applications. Specifically, a novel method to simultaneously optimise the cost and embodied carbon performance of steel building structures was explored in this paper. To achieve this, a parametric design model was developed to analyse code compliant structural configurations based on project specific constraints and rigorous testing of various steel beam sections, floor construction typologies (precast or composite) and column layouts that could not be performed manually by engineering practitioners. Detailed objective functions were embedded in the model to compute the cost and life cycle carbon emissions of the different material types used in the structure. Results from a comparative numerical analysis of a real case study illustrated that the proposed optimisation approach could guide structural engineers towards areas of the solution space with realistic design configurations, enabling them to effectively evaluate trade-offs between cost and carbon performance. This significant contribution implied that the optimisation model could reduce the time required for the design and analysis of multiple structural configurations especially during the early stages of a project. Overall, the paper suggested that the deployment of automated design procedures can enhance the quality as well as the efficiency of the optimisation analysis.

• 한국지하수토양환경학회지:지하수토양환경
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• 제21권3호
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• pp.21-34
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• 2016

In the present study, we applied various machine learning techniques comparatively for prediction of subsurface structures based on multiple secondary information (i.e., well-logging data). The machine learning techniques employed in this study are Naive Bayes classification (NB), artificial neural network (ANN), support vector machine (SVM) and logistic regression classification (LR). As an alternative model, conventional hidden Markov model (HMM) and modified hidden Markov model (mHMM) are used where additional information of transition probability between primary properties is incorporated in the predictions. In the comparisons, 16 boreholes consisted with four different materials are synthesized, which show directional non-stationarity in upward and downward directions. Futhermore, two types of the secondary information that is statistically related to each material are generated. From the comparative analysis with various case studies, the accuracies of the techniques become degenerated with inclusion of additive errors and small amount of the training data. For HMM predictions, the conventional HMM shows the similar accuracies with the models that does not relies on transition probability. However, the mHMM consistently shows the highest prediction accuracy among the test cases, which can be attributed to the consideration of geological nature in the training of the model.