• 한국철도학회논문집
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• 제12권6호
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• pp.902-908
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• 2009

TETRA는 유럽 전기 통신 표준협회에서 제안한 D-TRS 서비스의 표준이다. 현재 국가전력IT무선 기간망으로 TETRA가 채택되어, 다양한 활용을 위한 국가사업이 진행되고 있는 실정이다. 이와 같은 경우 TETRA 무선망을 이용하기 위해서는 TETRA 모뎀이 필요하게 된다. 따라서 각 제조사별로 존재하는 다양한 TETRA 모뎀의 성능 평가가 절실한 상황이다. 본 논문에서는 D-TRS 무선망 환경에서의 패킷 데이터 성능 평가를 위해 PED(Protocol Evaluation Data)를 제안하였다. 또한 Test Bed 상에서 TG(Traffic Generator)와 TA(Traffic Analyzer)를 이용하여 데이터 길이 및 전송 인터벌에 따른 성능 측정을 실시하여 모뎀의 성능을 알아보았다. 데이터 크기는 최초 10바이트에서 400바이트까지 10바이트씩 증가시키면서 측정하였고, 0.5초, 1초, 1.5초간격으로 각각 1000번 씩 전송하여 전송시간을 측정하였다. 측정한 전송시간을 바탕으로 평균전송속도, MER(Message Error Rate)을 도출하여 TETRA 모뎀 성능을 측정하였다. 본 논문에서 사용한 TETRA 모뎀은 EADS 사의 TMR880i 2대를 사용하였고, 교환기로는 EADS 사의 SwMI (Switching and Management Infrastructure)를 이용하였다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 춘계학술대회 논문집
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• pp.1671-1674
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• 2007

A PSD system has a lot of characteristic for safety. Trust of performance test is very important. But PSD performance test has an effect on trust by proficiency of test staff because it is difficult to automate. In that specially the effort test, manual opening and shutting test and abrasion measurement, test staff is demanded for proficiency. Therefore the paper repeated measurement in same condition and studied proficient factor of examiner according to increased measurement counter. As a result, measurement uncertainty has improved.

• 한국지열·수열에너지학회논문집
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• 제17권4호
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• pp.68-78
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• 2021

In order to solve the increasing deterioration of the energy shortage problem, ground-source heat pump (GSHP) systems have been widely installed. The control method is a significant component for maintaining the long-term performance and for reducing operation cost of GSHP systems. This paper presents the measurement and analysis results of the cooling performance of a GSHP system using capacity control with outdoor air temperature. For this, we installed monitoring equipments including sensors for measuring temperature, flow rate and power consumption, and then monitored operation parameters from July 9, 2021 to October 2, 2021. From measurement results, we analyze the effect of capacity control with outdoor air temperature on the cooling performance of the system. The average performace factor (PF) of the heat pump was 6.95, while the whole system was 5.54 over the measurement period. Because there was no performance data of the existing GSHP system, it was not possible to directly compare the existing control method and the outdoor air temperature method. However, it is expected that the performance of the entire system will be improved by adjusting the temperature of cold water produced by the heat pump, that is, the temperature of cold water on the load side according to the outside air temperature.

• 품질경영학회지
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• 제30권3호
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• pp.79-93
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• 2002

Many companies are struggling with the issue of performance measurement because a generally accepted framework does not exist. The Balanced Scorecard is designed to help firms that have historically overemphasized short-term financial performance. In this article, we discuss the interrelation between supply relationship and BSC. The Balanced Scorecard to measure quality performance with respect to supply relationship is suggested. Based on the survey of 84 venture firms, the validity of the measurement tool is tested statistically. Consequently, it was found that the suggested items have validity to measure supply relationship quality performance

• 한국주거학회:학술대회논문집
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• 한국주거학회 2003년도 정기총회 및 추계학술대회
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• pp.73-76
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• 2003

This paper is contents about method to measure interception performance of shock noise of floor slab of apartment house to be simple. In the case of interception performance of light floor impact sound level, according to measurement method, grade of sound insulation performance showed greatly differently. But, in the case of interception performance of heavy floor impact sound level, it was similar result in all measurement method. Therefore, use of simple method of measurement was examined by possible fact in case of interception performance of heavy floor impact sound level.

• 국제학술발표논문집
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• The 3th International Conference on Construction Engineering and Project Management
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• pp.1324-1327
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• 2009

Social infrastructure is the basis of public welfare and should be recognized and managed as important assets. Bridge is one of the most important infrastructures to be managed systematically because the impact of the failure is critical. It is essential to monitor the performance of bridges in order to manage them as an asset. But current analytical methods such as predictive modeling and structural analysis are very complicated and difficult to use in practice. To apply these methods, structural and material condition data collection should be performed in each element of bridge. But it is difficult to collect these detailed data in large numbers and various kinds of bridges. Therefore, it is necessary to collect data of major measurement items and predict the life of bridges roughly with advanced information technologies. When certain measurement items reach predefined limits in the monitoring bridges, precise performance measurement will be done by detailed site measurement. This paper describes the selection of major measurement items that can represent the tendency of bridge life and introduces automated bridge data collection test-bed using wireless sensor network technology. The following will be major parts of this paper: 1) Examining the features of conventional bridge management system and data collection method 2) Mileage concept as a bridge life indicator and measuring method of the indicator 3) Test-bed of automated and real-time based bridge life indicator monitoring system using wireless sensor network

• 디지털융복합연구
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• 제11권1호
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• pp.99-106
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• 2013

최근 기업의 개인정보 유출 사고와 관련한 금전적 손실이 점차 증가추세에 있으며 대외 이미지 손실 등의 간접적 피해도 무시 못 할 상황이 되었다. 이 같은 피해를 줄이기 위해서 개인정보보호투자에 대한 필요성이 증대되고 있다. 개인정보보호에 대한 투자가 활성화되기 위해서는 개인정보보호투자의 비용효과 분석 및 정성적 효과분석이 모두 반영된 성과측정 방법이 필요하다. 하지만 현재 국내외 개인정보보호 투자 성과측정에 관한 연구는 매우 미흡한 상황이다. 본 연구에서는 정량적 및 정성적 성과측정이 가능한 개인정보보호투자 모델을 제시하였다. 이를 위해 정보 보호투자 및 IT 투자성과측정 관련 기존 연구의 비교분석을 수행하였고, 개인정보보호 특성과 현실적용 가능성 측면을 고려하여 정량적 및 정성적 측정이 모두 가능한 WiBe 접근 방법론을 선택하였다. WiBe 방법론을 기반으로 개인정보보호 투자에 적절한 성과측정 모델과 16개의 성과측정 지표를 제시하였다. 특히, 정량적 효과측정에서 사전위협평가방법을 기반으로 기업 및 조직의 성격에 따른 개인정보보호의 투자의사 결정이 가능한 방법을 제시하였다. 포커스 그룹 인터뷰를 통한 성과 측정 지표의 검토 결과, 성과측정 지표는 실현 가능성 및 중요성 측면에서 모두 의미 있는 것으로 판명되었다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권6호
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• pp.2463-2482
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• 2016

Cloud services are often provisioned to their customers using user-friendly web browsers with flexible and rich plug-in environments. Delay is one of the fundamental performance metrics of these web-based services. Commonly-used network measurement tools usually only measure network delay and it may be difficult to infer the web-delay performance using only network layer measurement approaches. In this paper, we propose to evaluate the application layer delay in a browser-based network measurement platform using engineered scripts. We conducted a delay measurement study using instrumented scripts in the proposed browser-based measurement platform. Our investigation included a comparison study of three browser-scripting delay measurement methods, including Java applet, JSP and Flash ActionScript. We developed a browser-based delay measurement testbed over the Internet so that different delay measurement tools could be evaluated in the same real network environment including typical Internet paths and the Baidu cloud. We also decomposed the components of the end-to-end delay process of the above measurements to reveal the difference and relationship between the network-layer delay and the application-layer delay. Our measurement results characterize the stochastic properties of the application-layer delay over real Internet paths, and how these properties vary from the underlying network layer delay. This browser-scripting measurement approach can be easily deployed on different cloud service platforms to inspect their application-layer delay performance between end clients and the cloud platforms. Our measurement results may provide insights into designing new cloud services with enhanced quality-of-experience perceived by cloud users.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2006년도 정기학술발표대회 논문집
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• pp.492-495
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• 2006

건설사업 수행의 효율성을 통한 경쟁력 확보를 위해서는 기본 생산단위가 되는 개별 작업단위의 성과를 지속적으로 측정 ${\cdot}$ 관리하는 것이 필요하다. 하지만, 기존의 건설 프로젝트 성과측정은 공기, 품질, 원가, 안전 등의 개념을 지표화 하여 측정하고 있는데, 이는 결과 중심적인 성과측정이므로 각 단계의 생산과정이 종료된 후에는 이를 활용하여 생산과정을 통제하기 어렵다. 이에 본 연구는 린 건설개념을 바탕으로 개별 작업단위의 생산행위를 작업 흐름관점으로 해석하였고 이틀 측정하기 위한 지표로 신뢰성, 효율성, 효용성을 도출하였다. 그리고 각각의 성과지표간의 인과관계를 논리적으로 검증하여 본 연구가 제시한 성과지표가 건설 프로젝트의 결과적/사후적 성과를 사전에 통제할 수 있는 원인지표 혹은 사전적 관리지표로 활용될 수 있음을 제시하는데 그 의의가 있다.

• 한국군사과학기술학회지
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• 제24권6호
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• pp.577-590
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• 2021

In this paper, we theoretically analyzed the self-alignment/navigation performance in the accelerometer resonance state generated by dither motion of ring laser gyroscope in LINS and verified it through simulation. As a result of analysis, it is confirmed that the amplitude of the accelerometer measurement amplified in the accelerometer resonance state is decreased in the process of sampling per the navigation calculation period and that frequency is changed by the aliasing effect too. It was also analysed that the attitude error in self-alignment is determined by the amplitude/frequency of the accelerometer measurement, the gain of the self-alignment loop, and the velocity and position error in the navigation is determined by the amplitude/frequency/phase error of the accelerometer measurement. This analysis and simulation results show that the self-alignment and navigation performance is not be degraded only when the amplification factor of the accelerometer measurement in the accelerometer resonance state is 3 or less