• 한국신뢰성학회:학술대회논문집
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• 한국신뢰성학회 2006년도 학술발표대회 논문집
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• pp.158-164
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• 2006

The creep behavior of newly developed composite geogrids which consists of PET yarns sheathed in PP were evaluated using SIM. For the SIM procedure, three test parameters, the applied loads, temperature steps and number of ribs were investigated, The study confirmed that temperature steps of 10 and 14$^{\circ}C$ up to 80$^{\circ}C$ are applicable for composite geogrids due to the different transition temperatures between two materials. At applied loads of 40 and 50%, only primary creep state was measured, while secondary creep state appeared at the applied loads of 60%, The lifetimes of composite geogrids were estimated at each of loading level using statistical reliability analysis technique. The results show that the lifetimes longer than 100 years can be predicted within 16 hours. Therefore, SIM is very effective and economical accelerated creep test methods, especially for lifetime prediction. This gives guidelines for users to select the appropriate factor of safety against creep considering the field condition within shorter test times.

• International journal of advanced smart convergence
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• 제12권2호
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• pp.17-24
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• 2023

Given the surge in the elderly population, and increasing in dementia cases, there is a growing interest in digital therapies that facilitate steady remote treatment. However, in the cognitive assessment of digital therapies through clinical trials, the absence of log data as an essential evaluation factor is a significant issue. To address this, we propose a solution of utilizing weighted derived variables based on high-importance variables' accuracy in log data utilization as an indirect cognitive assessment factor for digital therapies. We have validated the effectiveness of this approach using machine learning techniques such as XGBoost, LGBM, and CatBoost. Thus, we suggest the use of log data as a rapid and indirect cognitive evaluation factor for digital therapy users.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1994년도 춘계공동학술대회논문집; 창원대학교; 08월 09일 Apr. 1994
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• pp.587-595
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• 1994

The use of flight training simulators has been increased remarkably during the past 20 years stimulated by the benefit that simulators can contribute to safety and training efficiency. Simulators have incorporated higher and higher levels of reality to provide more realistic training. Now, however, users are beginning to question how such reality is enough. Especially, it has raised question about the need for a notion system in the aircraft simulator. To help answer this question, this report describes notion cue requirements and types of motion system, and finally presents the assessment of the effectiveness of three different notion system alternatives.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 추계학술대회 논문집
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• pp.405-412
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• 1998

Recently“ride comfort”problem becomes increasingly important because of today's needs for train speedup The concept of term “riding comfort” is equivocal. Generally it is defined as the vehicle vibration. There are many studies on evaluation method of ride comfort for railway. But each of then recommends the different assessment method and the different guidance. So users must review whether they can apply it to their system or not. In this paper, we discuss the evaluation methods defined in the standards - ISO 2631, UIC 513 R, CEN DRAFT prENV 12299 and the ride index suggested by Sperling.

• 환경영향평가
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• 제20권6호
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• pp.879-890
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• 2011

The GOSAT (Greenhouse gases Observing SATellite) data provide new opportunities the most regionally complete and up-to-date assessment of $CO_2$. However, in practice, GOSAT records often suffer from missing data values mainly due to unfavorable meteorological condition in specific time periods of data acquisition. The aim of this research was to identify optimal spatial interpolation techniques to ensure the continuity of $CO_2$ from samples taken in the North East Asia. The accuracy among ordinary kriging (OK), universal kriging (UK) and simple kriging (SK) was compared based on the combined consideration of $R^2$ values, Root Mean Square Error (RMSE), Mean Error (ME) for variogram models. Cross validation for 1312 random sampling points indicate that the (UK) kriging is the best geostatistical method for spatial predictions of $CO_2$ in the East Asia region. The results from this study can be useful for selecting optimal kriging algorithm to produce $CO_2$ map of various landscapes. Also, data users may benefit from a statistical approach that would allow them to better understand the uncertainty and limitations of the GOSAT sample data.

• 한국비블리아학회지
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• 제26권4호
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• pp.83-104
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• 2015

본 연구는 대학도서관의 공간과 관련된 감성어휘들을 도출하여 향후 도서관 공간 설계 및 평가의 근거를 마련하고자 하는 연구이다. 이 연구의 목적을 달성하기 위하여 본 연구에서는 5단계의 추출 및 정제 과정을 통하여 대학도서관 공간과 관련된 주요 감성어휘 12개를 도출하였다. 감성어휘와 관련된 문헌조사 및 선행연구 분석, 대학도서관 사서 및 이용자를 대상으로 한 포커스그룹 인터뷰 및 설문조사, KJ법을 통한 유사도 평가 등을 한 결과, 최종적으로 '다양하다, 만족스럽다, 필요하다, 가득하다, 깨끗하다, 안정적이다, 알맞다, 조화롭다, 개방적이다, 따뜻하다, 자연스럽다, 훌륭하다'가 대학도서관 공간과 관련된 감성어휘로 선정되었다.

• 한국건축시공학회지
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• 제12권1호
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• pp.10-21
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• 2012

As one of the key IT applications, the project management information system (PMIS) played a significant role in construction management processes in Korea. On increasing use of PMIS, regular quality assessment to identify user's requirements of PMIS is necessary. However, there have been rare research efforts for quality assessment for the construction PMIS. This paper aims to propose a priority index of quality improvement for construction PMIS using the importance and satisfaction measures and to verify the discrimination power of the priority index by comparing it with other quality improvement priority index. In addition, this paper discusses some possible ways of PMIS quality improvement. The analysis of quality improvement priority was based on a questionnaire responded by 253 PMIS users (construction managers and constructors). The methods of PMIS improvement were based on the interviews with eight experts. These findings would be the foundation of further researches on PMIS quality improvement. However, more efforts are required to enhance the priority index, in terms of reflecting weighted values of quality assessment factors.

• Journal of Electrical Engineering and Technology
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• 제12권2호
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• pp.959-968
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• 2017

Electrical safety monitoring System (ESMS) is a critical component in modern power systems, which is characterized by large-scale access points, massive users and versatile requirements. For convenience of the information integration and analysis, the software development, maintenance, and application in the system, the cloud platform based ESMS is established and assessed in this paper. Firstly the framework of the system is proposed, and then the assessment scheme with a set of evaluation indices are presented, by which the appropriate cloud product can be chosen to meet the requirements of a specific application. Moreover, to calculate the weights of the evaluation indices under uncertainty, an improved interval AHP method is adopted to take into consideration of the fuzziness of expert scoring, the qualitative consistency test, and the two normalizations in the process of eigenvectors. Case studies have been made to verify the feasibility of the assessment approach for ESMS.

• 한국정보시스템학회지:정보시스템연구
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• 제26권2호
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• pp.43-62
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• 2017

Purpose This study provided empirical support for the model that explain the formation of privacy concerns in the perspective of Information Boundary Theory. This study investigated an integrated model suggesting that privacy concerns are formed by the individual's disposition to value privacy, privacy awareness, awareness of privacy policy, and government legislation. The Information Boundary Theory suggests that the boundaries of information space dependends on the individual's personal characteristics and environmental factors of e-commerce. When receiving a request for personal information from e-commerce websites, an individual assesses the risk depending on the risk-control assessment, the perception of intrusion give rise to privacy concerns. Design/methodology/approach This study empirically tested the hypotheses with the data collected in a survey that included the items measuring the constructs in the model. The survey was aimed at university students. and a causal modeling statistical technique(PLS) is used for data analysis in this research. Findings The results of the survey indicated significant relationships among environmental factors of e-commerce websites, individual's personal privacy characteristics and privacy concerns. Both individual's awareness of institutional privacy assurance on e-commerce and the privacy characteristics affect the risk-control assessment towards information disclosure, which becomes an essential components of privacy concerns.

• 자동차안전학회지
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• 제9권2호
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• pp.13-19
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• 2017

This paper presents safety assessment scenarios for cyclist autonomous emergency braking(AEB) system. To assess the safety performance of AEB in real traffic situation with limited number of scenarios, scenario should reflect the characteristics of real traffic collision cases. For this, statistic data of real traffic car-to-cyclist collision in Korea are analyzed. Many types of accidents are listed and categorized based on the movement of vehicle and cycle just before the collision. Then, the characteristics, main issues and limitations of each scenarios are discussed. Not only the test scenario itself but also the cost and time for the test are very important issues for the test scenarios to actually repeat the test for various systems. Also, the performance of AEB can be effected by the algorithm of AEB and the technical limitation of the sensors and hardwares. Therefore, required number of tests, possibility of dummy destruction and other technical issues are discussed for each scenarios. Based on these information, typical scenarios are selected. Also, using this information, vehicle speed range, cyclist speed and collision point are established. Proposed scenarios are verified and modified based on the vehicle test results. vehicle test was evaluated 5 times for each scenarios. Based on this results, final test scenarios are modified and proposed.