• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1043-1048
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• 2011

In the case of a low density branch line, these areas are operating at a loss. So much money is used for infrastructure maintenance cost. To solve the problem, our institute have a project to develop the Information & Communication Technology based train operation system. In a similar research in the Europe, The UK's Transport Research Laboratory experienced analysis of operational issue for developing ERTMS from Level II to Level III. In this paper, we study about railway operational issues before development of ICT based train operation system. An analysis target of operational issues are railway business process & data, drivability and moving or virtual block system.

• 전자통신동향분석
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• 제39권4호
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• pp.32-41
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• 2024

Building energy management plays a crucial role in improving energy efficiency and optimizing energy usage. To achieve this, it is important to monitor and analyze energy-related data from buildings in real time using sensors to understand energy consumption patterns and establish optimal operational strategies. Because of the uncertainties in building energy-related data, there are challenges in analyzing these data and formulating operational strategies based on them. Artificial intelligence (AI) technology can help overcome these challenges. This paper investigates past and current research trends in AI technology and examines its future prospects for building energy management. By performing prediction and analysis based on energy consumption or supply data, the future energy demands of buildings can be forecasted and energy consumption can be optimized. Additionally, data related to the surrounding environment, occupancy, and other building energy-related factors can be collected and analyzed using sensors to establish operational strategies aimed at further reducing energy consumption and increasing efficiency. These technologies will contribute to cost savings and help minimize environmental impacts for building owners and operators, ultimately facilitating sustainable building operations.

• 응용통계연구
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• 제26권1호
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• pp.49-58
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• 2013

자료포락분석(data envelopment analysis)은 여러 종류의 투입요소와 산출요소를 이용하여 의사결정단위(decision making unit)들 간의 상대적 효율성을 평가하기 위해 많이 사용되는 기법이다. 본 연구에서는 자료포락분석을 이용하여 지방대학들의 연구 및 교육분야에 대한 효율성을 분석한다. 먼저, 우리나라 국 공립 대학들의 효율성에 대해 살펴보고, 지역거점대학(regional flagship national universities)과 비거점(non-flagship)대학 간의 효율성이 통계적으로 유의한지 여부를 탐색한다.

• 한국시뮬레이션학회논문지
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• 제23권2호
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• pp.7-15
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• 2014

선유도어뢰 체계운용성능분석은 요구분석 및 개발을 위한 기술적 분석 자료를 제공하는 것을 목표로 하며, 결과적으로 선유도어뢰 체계공학에서 요구정의 활동을 지원한다. 본 논문에서는 문제정의, 정식화, 모델링, 시뮬레이션, 분석 결과 등 체계운용 성능분석을 위한 기술적 접근 방법과 분석 사례를 소개한다.

• 한국경영과학회지
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• 제39권3호
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• pp.23-40
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• 2014

This paper measures the operational efficiency of domestic online game companies and analyze its trends and patterns by using data envelopment analysis (DEA). DEA is a non-parametric approach to measuring the relative efficiency of decision-making units (DMUs) with multiple inputs and outputs. 14 online game companies are selected as DMUs and three inputs (number of employees, capital and asset) and three outputs (sales, operating profit and net profit) are selected as DEA variables. First, the output-oriented BCC model and super-efficiency model are employed to measure the static operational efficiency of the online game companies from 2003 to 2012. We also conduct the dynamic analysis with DEA window model to capture the trends of their operational efficiency influenced by internal and external environmental changes. The results are expected to provide fruitful implications for strategic decision making of online game companies and policy making for the online game industry.

• Earthquakes and Structures
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• 제8권4호
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• pp.859-887
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• 2015

Structural health monitoring (SHM) has gained in popularity in recent years since it can assess the performance and condition of instrumented structures in real time and provide valuable information to the asset's manager and owner. Operational modal analysis plays an important role in SHM and it involves the determination of natural frequencies, damping ratios and mode shapes of a constructed structure based on measured dynamic data. This paper presents the operational modal analysis and seismic response characterization of the Tsing Ma Suspension Bridge of 2,160 m long subjected to different earthquake events. Three kinds of events, i.e., short-distance, middle-distance and long-distance earthquakes are taken into account. A fast Bayesian modal identification method is used to carry out the operational modal analysis. The modal properties of the bridge are identified and compared by use of the field monitoring data acquired before and after the earthquake for each type of the events. Research emphasis is given on identifying the predominant modes of the seismic responses in the deck during short-distance, middle-distance and long-distance earthquakes, respectively, and characterizing the response pattern of various structural portions (deck, towers, main cables, etc.) under different types of earthquakes. Since the bridge is over 2,000 m long, the seismic wave would arrive at the tower/anchorage basements of the two side spans at different time instants. The behaviors of structural dynamic responses on the Tsing Yi side span and on the Ma Wan side span under each type of the earthquake events are compared. The results obtained from this study would be beneficial to the seismic design of future long-span bridges to be built around Hong Kong (e.g., the Hong Kong-Zhuhai-Macau Bridge).

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2010년도 춘계학술대회 논문집
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• pp.123-125
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• 2010

As the exterior noise emitted by a vehicle is getting more and more attention, simulated pass-by measurements become more important. This well established method provides information about the total noise emitted by the vehicle. For a vehicle manufacturer it is not only interesting to know about the total noise but also to know how this total exterior noise is composed of different contributions, such as for example the contribution of the engine, the intake or exhaust system. Transfer path analysis (TPA) provides a separation of these contributions for each of the pass-by microphones alongside the track. Presented is a method for fast and efficient determination of the contributions of multiple sources using operational transfer path analysis (OTPA). The calculation of the transfer characteristics between the reference measurement points on the vehicle and the corresponding response points of both microphone lines are carried out while operation of the vehicle. As result of the contribution analysis from operational transfer path analysis, the characteristic noise level as function of the covered distance is displayed for all individual sound sources, thus providing in depth information for sound quality engineering.

• 산업노동연구
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• 제19권1호
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• pp.65-104
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• 2013

본 연구는 자원기반관점을 기초로 고성과작업시스템-종업원성과-운영성과 간 관계를 실증적으로 검증하고자 하였다. 조직수준의 고성과작업시스템과 개인수준의 종업원 태도 간 실증분석을 위해 위계적 선형모형(hierarchical linear modeling)을 활용한 다수준분석을 실시하여 인과관계의 정확성을 높였다. 이를 위해, 제3차 인적자원기업패널(HCCP: Human Capital Corporate Panel) 데이터 가운데 316개 기업과 7,872명(팀장 923명 포함)의 응답자를 대상으로, 고성과작업시스템이 개인수준인 종업원성과에 미치는 영향을 확인하였다. 이후, 분석수준을 일치시키기 위해 개인수준(종업원성과)과 팀수준(운영성과)의 패널자료를 조직수준으로 집산(aggregation)하여 타당화 검증을 실시하고, 조직수준에서 매개효과를 검증하였다. 그 결과, 고성과작업시스템은 종업원성과(직무만족, 조직몰입, 신뢰)와 운영성과에 각각 유의한 영향을 미치는 것으로 나타났다. 종업원성과 개별변수의 매개효과 검증에서는 직무만족과 신뢰가 고성과작업시스템과 운영성과 간 관계를 매개하는 것으로 나타났다. 결론에는 연구의 결과, 이론적 시사점 및 한계점을 제시하고 있다.

• Structural Monitoring and Maintenance
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• 제7권2호
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• pp.149-166
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• 2020

This paper presents the results of an experimental investigation on a vibration-based damage identification framework for a steel girder type and a truss bridge based on acceleration responses to operational loading. The method relies on sensor clustering-based time-series analysis of the operational acceleration response of the bridge to the passage of a moving vehicle. The results are presented in terms of Damage Features from each sensor, which are obtained by comparing the actual acceleration response from the sensors to the predicted response from the time-series model. The damage in the bridge is detected by observing the change in damage features of the bridge as structural changes occur in the bridge. The relative severity of the damage can also be quantitatively assessed by observing the magnitude of the changes in the damage features. The experimental results show the potential usefulness of the proposed method for future applications on condition assessment of real-life bridge infrastructures.

• 설비공학논문집
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• 제12권12호
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• pp.1090-1097
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• 2000

Predicting building energy use can be useful to evaluate its energy performance. This study proposed empirical approach for predicting building energy use with regression analysis. For the empirical analysis, simple regression models were developed based on the historical energy consumption data as a function of daily outside temperature, the predicting equations were derived for different operational modes and day types, then the equations were applied for predicting energy use in a building. BY selecting a real building as a case study, the feasibilities of the empirical approach for predicting building energy use were examined. The results showed that empirical approach with regression analysis was fairly reliable by demonstrating prediction accuracy of $pm10%$ compared with the actual energy consumption data. It was also verified that the prediction by regression models could be simple and fairly accurate. Thus, it is anticipated that the empirical approach will be useful and reliable tool for many purposes: retrofit savings analysis by estimating energy usage in an existing building or the diagnosis of the building operational problems with real time analysis.