• 국제학술발표논문집
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• The 6th International Conference on Construction Engineering and Project Management
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• pp.174-178
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• 2015

This paper presents a new method for forecasting construction project cost and time at completion or at any intermediate time horizon of the project duration. The method is designed to overcome identified limitations of current applications of earned value method in forecasting project cost and time. The proposed method usesfuzzy set theory to model uncertainties associated with project performance and it integrates the earned value technique and the contractors' judgement. The fuzzy set theory is applied as an alternative approach to deterministic and probabilistic methods. Using fuzzy set theory allows contractors to: (1) perform risk analysis for different scenarios of project performance indices, and (2) perform different scenarios expressing vagueness and imprecision of forecasted project cost and time using a set of measures and indices. Unlike the current applications of Earned Value Method(EVM), The proposed method has a numberof interesting features: (1) integrating contractors' judgement in forecasting project performance; (2) enabling contractors to evaluate the risk associated with cost overrun in much simpler method comparing with that of simulation, and (3) accounting for uncertainties involved in the forecasting project cost.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.565-571
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• 2001

As a method of structural optimization, a practical algorithm based on the Taguchi method is developed. The Taguchi method is applied iteratively updating the level values of design variables. The design region is translated or reduced during optimization and by appropriate choice of reduction factor and initial level intervals, a near-optimum solution can be found very efficiently. To treat inequality constraints, a variable penalty method is utilized. A software system named 'DS/Taguchi' is developed by integrating the proposed algorithm and commercial finite element analysis codes on the parametric CAD platform. Two examples are taken to examine the performance of the proposed algorithm and the developed software system.

• 디지털산업정보학회논문지
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• 제6권1호
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• pp.143-149
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• 2010

In ubiquitous environment, information retrieval using collaborative filtering is a popular technique for reducing information overload. Collaborative filtering systems can produce personal recommendations by computing the similarity between your preference and the one of other people. We integrate the collaboration filtering method and context-aware information retrieval method. The proposed method enables to find some relevant information to specific user's contexts. It aims to makes more effective information retrieval to the users. The proposed method is conceptually comprised of two main tasks. The first task is to tag context tags by automatic tagging technique. The second task is to recommend items for each user's contexts integrating collaborative filtering and information retrieval. We describe a new integration method algorithm and then present a u-commerce application prototype.

• 디지털산업정보학회논문지
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• 제16권1호
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• pp.21-31
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• 2020

Internet of Things is growing rapidly. As it evolves, the amount of data is increasing significantly. It requires a new personalized information retrieval method. Internet of Things is defined as uniquely identifiable interoperable connected object. The first definition of Internet of Things was from Things oriented perspective. However, previous studies about personalized information retrieval method do not consider Things. To meet user's individual needs, previous studies concentrate on only human, not Things. In this paper, we propose a personalized information retrieval method considering participating device in Internet of Things. It provides personalized information using data type preference for each device. Moreover, it provides personalized results by integrating data type preference for set of devices. This paper describes a new personalized retrieval method and algorithm. It consists of five steps. Then, it presents four scenarios using proposed method. The scenarios show our work is more effective and efficient than existing one.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권11호
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• pp.5592-5609
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• 2017

JPEG steganography detection is an active research topic in the field of information hiding due to the wide use of JPEG image in social network, image-sharing websites, and Internet communication, etc. In this paper, a new steganalysis method for content-adaptive JPEG steganography is proposed by integrating the evolutionary feature selection and classifier ensemble selection. First, the whole framework of the proposed steganalysis method is presented and then the characteristic of the proposed method is analyzed. Second, the feature selection method based on genetic algorithm is given and the implement process is described in detail. Third, the method of classifier ensemble selection is proposed based on Pareto evolutionary optimization. The experimental results indicate the proposed steganalysis method can achieve a competitive detection performance by compared with the state-of-the-art steganalysis methods when used for the detection of the latest content-adaptive JPEG steganography algorithms.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2002년도 추계 학술대회논문집
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• pp.41-46
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• 2002

A numerical simulation was made to determine the motion of particles in the fluid. The simulation is based on the Eulerian-Lagrangian method. The fluid motion was solved using a PISO-based finite-element method and a $\kappa-\epsilon$ model of turbulence. In the Lagrangian method for the solid phase, the trajectories of particles are calculated by integrating the equations of motion of a single Particle, and the collision between particles are taken into account. The influence of particles on the fluid phase is taken into account by introducing source terms in the Eulerian equations govering the fluid flow. It is known as the particle-source-in-cell (PSIC) method. Also, the turbulent effect in the particles and fluid notion is considered. The numerical results were compared with the experiment for a two-phase flow in a vertical pipe.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2003년도 춘계 학술발표회논문집
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• pp.129-139
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• 2003

The response displacement method is the most frequently used method for seismic design of buried structures. This method is pseudo-static method, and the evaluations of velocity response spectrum of seismic base and response displacement of surrounding soil are the most important steps. In this study, the evaluation of velocity response spectrum of seismic base according to the Korean seismic design guide and the simple method of calculating the response displacement were studied. It was found that velocity response spectrum of seismic base can be estimated by direct integrating the ground-surface acceleration response spectrum of soil type $S_{A}$, and the evaluation of the response displacement using double cosine method assuming two layers of soil profile shows the advantages in the seismic design.n.

• 한국정보통신학회논문지
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• 제20권7호
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• pp.1335-1341
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• 2016

철도의 원활한 운행을 보장하기 위하여 신호, 전철전력, 통신, 설비 등 분야별로 독립된 시스템이 구축되어 운영되고 있으나, 각각의 현장 설비가 센싱 데이터를 중앙관제로 전송하는 매체나 프로토콜이 서로 상이하다. 현재 연구개발을 진행하고 있는 실시간 철도안전 관제시스템은 분산된 안전에 관련된 데이터를 통합하여 위험을 예측하고 철도 사고를 예방하기 위한 것으로, 분산되어 있는 안전 관련 데이터를 통합하여 획득하는 것이 필수적이다. 이를 위하여 서로 상이한 매체나 다양한 프로토콜로 전송되는 정보를 기존 어플리케이션의 변경 없이 수용할 수 있는 데이터 변환이 필요하다. 본 연구에서 다양한 방식으로 전송되는 정보를 통합 관리하기 위한 데이터 변환 사례를 조사하고, 기존 방식에 전송기능을 부가하여 일체화한 XML 기반의 프로토콜 변환 방안을 제시하고, 이를 구현하고자 한다.

• 한국건설관리학회논문집
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• 제12권6호
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• pp.42-53
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• 2011

2004년 예정가격 산정방법으로 실적공사비 적산제도가 본격적으로 시행되면서 상대적으로 표준품셈 적산제도의 적용이 하락하였다. 그러나 2010년 하반기 예정가격 산정시 표준품셈 적산제도의 적용비중은 45%이며, 여전히 높은 적용비중을 유지하고 있다. 현행 표준품셈은 예정가격의 산정에 과도한 시간이 소요되고, 시공계획과 자원분배에 적용하기 어려운 단점이 있다. 이와 같은 단점을 개선하기 위하여 본 연구에서는 국내외 품셈의 형식을 고찰하여 이를 국내 도로분야 대표공종에 적용하여 기존 품셈을 일단위 작업조 기반 생산성 정보로 산출하여 유사한 조건하에서 일본 미국의 생산성 정보 및 현장자문을 통한 정보와 비교하였다. 본 연구를 통해 적용된 작업조기반 생산성 정보 산출 방법과 산출 정보의 효용성을 확인하고자한다. 이러한 과정을 통하여 표준품셈을 통한 작업조기반 생산성 정보 산정 방법'과 일단위 작업조 기반 생산성 정보를 제시하고자 한다.

• Safety and Health at Work
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• 제3권3호
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• pp.199-208
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• 2012

Objectives: Although evidence-based medicine (EBM) is a useful method for integrating evidence into the decision-making process of occupational physicians, occupational physicians lack EBM knowledge and skills, and do not have the time to learn the EBM method. In order to enable them to educate themselves at the time and place they prefer, we designed an electronic EBM course. We studied the feasibility and utility of the course as well as its effectiveness in increasing EBM knowledge, skills, and behaviour. Methods: Occupational physicians from various countries were included in a within-subjects study. Measurements were conducted on participants' EBM knowledge, skills, behaviour, and determinants of behaviour at baseline, directly after finishing the course and 2 months later (n = 36). The feasibility and utility of the course were evaluated directly after the course (n = 42). Results: The course is applicable as an introductory course on EBM for occupational physicians in various countries. The course is effective in enhancing EBM knowledge and self-efficacy in practising EBM. No significant effect was found on EBM skills, behaviour, and determinants of behaviour. After the course, more occupational physicians use the international journals to solve a case. Conclusion: An electronic introductory EBM course is suitable for occupational physicians. Although it is an effective method for increasing EBM knowledge, it does not seem effective in improving skills and behaviour. We recommend integrating e-learning courses with blended learning, where it can be used side by side with other educational methods that are effective in changing behaviour.