• Structural Engineering and Mechanics
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• 제41권1호
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• pp.83-94
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• 2012

Assessment of a monumental concrete arch bridge with a total length of 210 meters having three major spans of 30 meters and a height of 65 meters, which is located in an earthquake-prone region in southern part of the country is presented in this study. Three-dimensional finite element model of the bridge was generated using a commercially available general finite element analysis software and based on the outcomes of a series of in-depth acceleration measurements that were conducted on-site, the model was refined. By using the structural parameters obtained from the dynamic and the static tests, calibrated model of the bridge structure was obtained and this model was used for necessary calculations regarding structural assessment and evaluation.

• 전기학회논문지P
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• 제62권4호
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• pp.216-222
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• 2013

Handover is a technical methodology to support mobility of wireless communication users, which mainly affects the capacity of wireless communication systems and the quality of service (QoS) of link level signal. However, in OFDMA-based cellular systems, there are few published technical reports investigating handovers with respect to diversity gains and resource consumption depending on what handover technique is adopted. In this paper, we propose handover schemes exploiting transmit diversity and macro-diversity in order to increase capacity of OFDMA-based wireless communication systems, and analyze their performance. In cellular environments, depending on what handover scheme is selected, average signal-to-interference-and-noise ratio is calculated first for a handover user in order to evaluate the link level QoS. Through this technical evaluation for handover schemes, we conclude what handover scheme is suitable for OFDMA-based cellular systems.

• 한국문헌정보학회지
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• 제31권3호
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• pp.109-134
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• 1997

이 연구는 국내 과학기술계에서 구축하고 있는 서지 DB의 품질 문제를 다루고 있다. 구체적으로, 과학기술분야의 중추적인 정보유통기관인 KORDIC이 1990년대 초부터 구축해 오고 있는 KRISTAL DB 중에서 핵심이라 할 수 있는 UNION DB와 SATURN DB를 선정하여 그 품질을 평가하고 개선방안을 제시한다. 특히, UNION DB와 SATURN DB의 품질 평가를 위한 접근 방식에서, 기존의 시스템개발자 중심의 논리를 배격하고 이용자 중심의 평가 기준을 제시함으로써 '정보시스템의 설계 및 평가'에 있어서 이용자의 중요성을 강조한다.

• Nuclear Engineering and Technology
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• 제53권5호
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• pp.1634-1641
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• 2021

Exposure to gamma-rays is hazardous for humans and other living beings because of their high penetration through the materials. For this reason, shielding materials (usually lead, copper and stainless steel) are used to protect against gamma rays. This study's objective was to prepare ceramic materials for gamma radiation shielding by using different natural bentonite clays. Gamma-ray attenuation performances of the prepared shielding materials at different thicknesses were investigated and evaluated for different gamma-ray energies from different standard point gamma radiation sources (²⁵¹Am, ⁵⁷Co, ¹³⁷Cs, ⁶⁰Co, and ⁸⁸Y). The mass and linear attenuation coefficients of the prepared ceramics vary between 0.238 and 0.443 cm² g^-1 and between 0.479 and 1.06 cm^-1, respectively, depending on their thicknesses. Results showed that these materials could be prioritized because of their evidential properties of gamma radiation protection in radiation applications.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2023년도 제68차 하계학술대회논문집 31권2호
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• pp.29-32
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• 2023

본 논문에서는 외국인과 발음에 어려움을 겪고 있는 한국인들을 대상으로 음성 녹음을 진행하여 점수를 반환받는 웹 사이트를 소개한다. 이 웹 사이트의 목적은 사용자들의 발음 향상을 돕는 것이다. 음성 인식 API와 발음 평가 API를 사용하여 사용자의 발음을 정확하게 평가하고 피드백을 제공함으로써, 외국어 학습자와 발음에 어려움을 겪는 한국인들이 보다 원활하게 의사소통할 수 있도록 돕는다. 향후 연구로는 이 시스템의 사용자들에게 학습 성취에 대한 동기 부여를 하는 기능을 추가해 학습 효과를 높이도록 개선할 것이다.

• 한국게임학회 논문지
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• 제9권1호
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• pp.63-74
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• 2009

본 논문은 게임성 평가 모델 설계를 기반으로 온라인 게임성 평가 시스템 설계 및 구현을 중점적으로 연구하였다. 온라인 게임성 평가 시스템이란 평가 요소를 정의한 모델 설계를 통하여 온라인상에서 게임을 실시간으로 평가하는 시스템을 의미한다. 게임성 평가 시스템은 사용성 평가(Heuristic Evaluation) 기법을 활용하여 기술적 요소, 관리적 요소, 사회적 요소, 경쟁력 요소의 4부분으로 평가를 실시하였다. 게임성 평가의 객관성과 타당성 검증을 위하여 초급자, 중급자, 전문가 세 분류를 통하여 평가를 실시하여 신뢰도를 높였으며, 게임성 평가 포럼을 개최하여 다양한 계층의 의견을 수렴하였다.

• 품질경영학회지
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• 제50권4호
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• pp.665-677
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• 2022

Purpose: The purpose of this study is to analyze the current status and investigate relevant indicators so that R&D performance evaluation suitable for government-funded research institutes can proceed. A suitable performance evaluation model was presented based on the surveyed indicators. Based on the presented performance evaluation model, the importance was analyzed to calculate the weight for each indicator of the performance evaluation model. Methods: The method applied in this study presented a performance evaluation model based on the organizational performance evaluation cases of advanced overseas countries. By using the AHP(Analytic Hierarchy Process) technique, the weight of each indicator of the performance evaluation model was studied. Results: As a result of examining the indicators necessary for the evaluation model, focusing on overseas cases, 13 evaluation items were derived. A weight was calculated for the importance of the study results. And the scientific/technical research results showed the highest excellence. Conclusion: Key indicators of performance evaluation suitable for government-funded research institutes were derived and presented through detailed modeling in three stages. A realistic model that can objectively evaluate the performance of government-funded research institutes was proposed using the AHP technique.

• 경영정보학연구
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• 제8권1호
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• pp.265-285
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• 2006

본 연구는 IT프로젝트 사전타당성 평가항목을 도출하고, 각 평가항목의 가중치를 AHP 기법에 의하여 산출하였으며, 3개 IT프로젝트 유형에 따른 평가항목별 가중치 차이를 통계적으로 검증하였다. 국내 민간기업 및 공공조직에서 제안된 79개 IT프로젝트에 대한 AHP 조사에서 7개 평가항목의 가중치는 재무적 효과 25.14%, 전략적 가치 22.34%, 직접비용 14.44%, 리스크 12.05%, 기술적 필요성 11.50%, 정치적 고려 8.26%, 간접비용 6.41%로 나타났다. 예상대로 재무적 효과, 전략적 가치, 직접비용의 가중치가 높게 나타난 반면, 최근의 TCO 모델이나 이론적 연구에서 중시되고 있는 간접비용이 실무현장에서는 그다지 중요하게 고려되지 않는 것으로 나타났다. 특히 대부분 신규 IT투자에서 실질적으로 가장 민감하게 영향을 미치고 있다고 간주되는 CEO 관심, 현업부서장의 추진의지 등과 같은 정치적 고려항목이 낮게 나타난 것은 의외의 현상이며, 그 원인에 대한 체계적 분석을 향후 연구과제로 제안한다. 그리고 ANOVA 분석 결과 거래처리형, 정보제공형, 인프라형 3개 프로젝트 유형별로 평가항목 가중치가 다른 것으로 분석되었다.

• Journal of Advanced Marine Engineering and Technology
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• 제39권5호
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• pp.527-535
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• 2015

As a new technical approach, a hydraulic and magnetic clamp device was attempted to realize a magnetic clamp crane system that uses 8 simultaneously actuating individual hydraulic cylinders. Through this approach, a Sr type of ferritic permanent magnet ($SrO{\cdot}6Fe_2O_3$), not the previously employed electro-magnet, was utilized for the purpose of lifting and transporting the heavy weighted and oversized curved steel plates used for manufacturing the ships. This study is aimed at manufacturing and developing the hydraulic magnetic clamp prototype, which is composed of three main parts - the base frame, cylinder joint, and magnet joint - in order to safely transport such curved steel plates. Furthermore, this research was pursued to conduct a performance evaluation as to the prototype manufacture and acquire the planned quantity value and the development purpose items. The most significant item for a performance evaluation was estimated for the magnetic adhesive force (G) and in this process, a ferritic permanent magnet (Sr type) with 3700~4000 G of residual induction (Br) and 2640/2770 Oe of coercive force (Hc) was utilized. In addition, other relevant items such as hoist tension (kN), transportation time (sec), and the applied load (Kgf) exerted on the hydraulic cylinders were also evaluated in order to acquire the optimum quantity value. As a result of the evaluation, the relevant device turned out to be suitable for safely transporting the curved steel plates.

• 한국태양에너지학회 논문집
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• 제35권6호
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• pp.51-60
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• 2015

In statutes on the promotion of distribution of new and renewable energy, which were revised in 2014, daylight system and fuel cell were added in addition to existing new and renewable energy sources. This study, therefore, aimed at setting up targets for the introduction of daylight system and analyzing the installation rate of new and renewable energy which can be provided by daylight system for the aggressive use of daylight system, thereby deducting the optimal combination ratio with other new and renewable energy sources. The results of the study are as follows. First, when a prism-shaped daylight system was installed to a round indoor gymnasium among domestic indoor gymnasiums, out of a supply obligations allotment rate of 15% of new and renewable energy, the rate of daylight system was basically set at 2.5%. Second, therefore, with daylight system coming first, the lacked supply obligations rate was taken up by solar photovoltaic, solar heat and geothermal heat. In addition, using the KRESS Program, economic, technical, environmental and complexity evaluations for the upper 5% was made, deducting the optimal ratio of the system. The results produced the following optimal combination ratios: solar photovoltaic (83.3%) in economic evaluation, solar heat (8.3%) and geothermal heat (75%) in technical evaluation, solar photovoltaic (83.3%) in environmental evaluation, and solar photovoltaic (83.3%, the same as in economic evaluation) in complexity evaluation.