• Structural Engineering and Mechanics
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• v.44 no.3
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• pp.379-403
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• 2012

In recent years, the need for optimal design of structures under time-history loading aroused great attention in researchers. The main problem in this field is the extremely high computational demand of time-history analyses, which may convert the solution algorithm to an illogical one. In this paper, a new framework is developed to solve the size optimization problem of steel truss structures subjected to ground motions. In order to solve this problem, the covariance matrix adaptation evolution strategy algorithm is employed for the optimization procedure, while a generalized regression neural network is utilized as a meta-model for fitness approximation. Moreover, the computational cost of time-history analysis is decreased through a wavelet analysis. Capability and efficiency of the proposed framework is investigated via two design examples, comprising of a tower truss and a footbridge truss.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.567-576
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• 2020

This study develops a mediating model to explore the relationships between organizational characteristics, manager's knowledge, management commitment, user involvement, information quality, and management information system effectiveness in small- and medium-sized enterprises in Vietnam. Adapting scales from previous research, the authors designed questionnaires, which they distributed to respondents in Vietnamese small- and medium-sized enterprises. Also, by employing a meta-analytic path analysis throughout structural equation modelling (SEM) with sample of 356 respondents, authors indicate that organizational characteristics are directly related to management information systems effectiveness. Moreover, manager's knowledge, user involvement, and information quality show their important roles in the increase of management information system effectiveness, yet management commitment does not indicate a similar role in the growth of management information system effectiveness. Bootstrapping is utilized to discover the meditating role of information quality, illustrating that quality information mediates the linkages between user involvement, organizational characteristics, and management information systems. However, the mediating role of information quality in the relationship between management commitment, manager's knowledge, and management information systems is not significant. This study contributes to the management information system literature as well as to enhance MIS effects in small and medium-sized enterprises.

• Journal of Ocean Engineering and Technology
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• v.26 no.6
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• pp.80-85
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• 2012

The methods of robust design optimization (RDO) and reliability-based robust design optimization (RBRDO) were implemented in the present study. RBRDO is an integrated method that accounts for the design robustness of an objective function and for the reliability of constraints. The objective function in RBRDO is expressed in terms of the mean and standard deviation of an original objective function. Thus, a multi-objective formulation is employed. The regressive approximate models are generated via the moving least squares method (MLSM) and constraint-feasible moving least squares method (CF-MLSM), which make it possible to realize the feasibility regardless of the multimodality/nonlinearity of the constraint function during the approximate optimization processes. The regression model based RBRDO is newly devised and its numerical characteristics are explored using the design of an actively controlled ten bar truss structure.

• 한국IT서비스학회:학술대회논문집
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• 2008.05a
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• pp.431-436
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• 2008

지난 몇 년 동안 컴퓨터 네트워크에는 다음과 같은 중요한 일이 발생하였다. 장치 대 장치, 기계 대 기계의 통신이 컴퓨터 네트워크에서 주요한 이슈로 떠오른 것이다. 그 중에 가장 눈에 띄는 주제 중 하나인 WSN에 속한 RFID이다. 이 RFID와 WSN의 통합에 대한 아이디어는 퍼베이시브 컴퓨팅에서 나오게 되었다. RFID와 WSN은 퍼베이시브 컴퓨팅의 주요 요소이고, 이 두 가지 기술은 현실 세계와 가상 세계를 묶어주는 역할을 한다. 하지만 RFID와 WSN은 각각 병렬적으로 개발되고 있으며, 비즈니스 애플리케이션의 통합을 위해서는 자세한 규칙과 방법들이 연구되어야 한다. 본 논문에서는 RFID와 WSN가 통합된 비즈니스 도메인을 위한 시스템 아키텍처 프레임워크 모델링을 제안한다. RFID와 WSN을 동시에 이용해서 SCM을 관리하는 것이다. 이를 위해서 RFID와 WSN, 각각의 기술에 대한 요소를 제안한다. 본 논문에서는 그래픽 모델링 환경(GME)을 이용해서 비즈니스 도메인을 위한 시스템 아키텍처 프레임워크 모델을 만든다.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.517-520
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• 2008

This paper implements the graphic service template authoring tool based on the service template object model of describing the meta information of the services in the semantic web service environment. Our proposed system provides the robot services by constructing web services automatically and making the appropriate service plans. Moreover, it can create, append, delete, and update the service templates of URC based on STDL, and provide the graphic function on service template resources. In order to provide the user friendly environment in the service template phase, we implement the various editing environment : flow view style, grid view style, and text view style. We also provide the easy editing function by realizing abstract service block based on the robot API. Finally we can offer the intelligent and autonomous service of service agent based on semantic information.

• Journal of Electrical Engineering and Technology
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• v.9 no.3
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• pp.859-865
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• 2014

Optimization of an electric machine is mainly a nonlinear multi-modal problem. For the optimization of the multi-modal problem, many function calls are required with much consumption of time. To address this problem, this paper proposes a novel hybrid algorithm in which function calls are less than conventional methods. Specifically, the proposed method uses the kriging metamodel and the fill-blank technique to find an approximated solution in a whole problem region. To increase the convergence speed in local peaks, a parallel gradient assisted simplex method is proposed and combined with the kriging meta-model. The correctness and usefulness of the proposed hybrid algorithm is verified through a mathematical test function and applied into the practical optimization as the cogging torque minimization for an interior permanent magnet synchronous machine.

• Journal of the Korea Institute of Military Science and Technology
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• v.22 no.4
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• pp.527-535
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• 2019

Hanger in a rail-launched missile protrudes in general and causes to increase significant drag force. One method to avoid the significant increase of drag force is to apply fairings on the hanger. In this paper, sloping shaped fairing parameters of height, width, and length are optimized to minimize the drag force under subsonic speed region by examining three configurations of fairings : front-fairing only, rear-faring only, and the both front and rear fairing. We use Latin Hypercube Sampling method to determine the experimental points, and computational fluid dynamics with incompressible RANS solver was applied to acquire the data at sampling points. Then, we construct a meta model by kriging method. We find the best choice among three configurations examined : both front and rear fairing reduce the drag force by 63 % without the constraint of fairing mass, and front fairing reduced the drag force by 52 % with the constraint of hanger mass.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.951-954
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• 2004

최근 디지털 지식기반 사회에 대응하는 교육의 형태로 e-Learning이 교육적 대안으로 급부상하면서, 시스템의 상호 운영성 및 컨텐츠 명세, 활용을 지원하기 위한 표준화에 따른 연구가 국내외에서 급속도로 확산되고 있다. 특히, 국제표준기관에서 제시한 e-Learning 개발 환경을 위한 Learning Technology Standard Architecture(LTSA)와 Sharable Content Object Reference Model(SCORM)을 제정하여 컨텐츠의 사용과 상호 호환을 가능하게 함으로써 e-Learning의 효율성을 증대시키고 산업 시장의 확장을 이룰 수 있다. 또한, 현재 많은 교육관련 업체에서는 SCORM 체계를 기반으로 한 학습 컨텐츠들을 개발하여 제공하고 있다. 따라서, 본 논문에서는 국제 표준 기술인 SCORM을 기반으로 개발된 학습 컨텐츠를 체계적으로 지원하기 위해 컨텐츠 관리 시스템 개발에 대한 기술을 정의하고, 다양한 관점의 컨텐츠 메타 데이터를 식별, 분류함으로써 컨텐츠의 생성과 저장, 검색 나아가 형상관리를 위한 기본 정보로 이용 가능하다. 또한 이들 메타 데이터를 기반으로 한 학습 컨텐츠 관리 시스템의 프로토타이핑을 제시함으로써 재사용성과 유지보수성 향상을 통해 컨텐츠 개발의 용이성과 품질 및 생산성을 높일 수 있다.

• Journal of Distribution Science
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• v.19 no.11
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• pp.69-80
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• 2021

Purpose: Consumers have unique behaviors that are classified based on their interests and considerations before buying. They are predicted will change due to the pandemic of COVID-19. This study provides insights for retailers about the dynamic of consumer behavior before and during the pandemic, including future predictions. Research design, data and methodology: The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement was applied in this study. Seven studies that were selected from five databases meet the criteria for cohort and cross-sectional analyses of gender, age, store types, and environmental concerns. Results: Consumer's gender and age contribute to consumer behavior change. Both offline and online stores can be integrated as omnichannel rather than substitute each other. Product distribution and consumer budget need to be reevaluated by retailers, while internet security is the most essential factor when developing their online transactions. Conclusions: COVID-19 pandemic has a significant impact on changing consumer behavior in most countries. Retailers are encouraged to adapt to the changes by modifying their business model with technology. However, it is still speculated and cannot be generalized due to different cultural and contextual factors. Future studies are always needed to synchronize along with the transition of consumers' behavior.

• Archives of Plastic Surgery
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• v.48 no.4
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• pp.433-439
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• 2021

Acellular dermal matrices (ADM) are a novel graft. The goal of this systematic review is to evaluate the evidence behind differences in human and porcine ADM, irrelevant of manufacturing method, and to determine if there is enough of an evidence base to change clinical practice. An extensive literature search was performed through MEDLINE and Embase with search terms defining a population, intervention and outcome. Title and abstract exclusion were performed with other exclusion criteria. In 191 articles were found after exclusion of duplicates, with only 29 remaining following exclusions. Ten studies were found to have level I and II evidence (I=3, II=8), of which two were histopathological, one was an animal model, one was a systematic review, and six were clinical. The remaining studies were reviewed and considered for discussion, but did not hold high enough standards for medical evidence. Strong clinical evidence already exists for the use of human ADM, but questions of access, cost, and ethics require consideration of a xenograft. Histopathologically, evidence suggests minimal long-term differences between human and porcine ADM, although there is a short acute immune response with porcine ADM. Clinically, there is limited difference in outcomes, with a small range in effect of different ADM preparations. Considering the effectiveness of ADM in wound healing, more high-level research with appropriate statistical analysis to facilitate a future meta-analysis is recommended to justify a transition from human to porcine ADM.