• 대한전기학회논문지:전력기술부문A
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• 제55권10호
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• pp.399-409
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• 2006

This paper presents a novel method for satisfying the thermal comfort of indoor environment and reducing the summer peak demand power by minimizing the power consumption for an Air-conditioner within a space. Korea Electric Power Corporation (KEPCO) use the fixed duty cycle control method regardless of the indoor thermal environment. However, this method has disadvantages that energy saving depends on the set-point value of the Air-Conditioner and direct load control (DLC) has no net effects on Air-conditioners if the appliance has a lower operating cycle than the fixed duty cycle. In this paper, the variable duty cycle control method is proposed in order to compensate the weakness of conventional fixed duty cycle control method and improve the satisfaction of residents and the reduction of peak demand. The proposed method estimates the predict mean vote (PMV) at the next step with predicted temperature and humidity using the back propagation neural network model. It is possible to reduce the energy consumption by maintaining the Air-conditioner's OFF state when the PMV lies in the thermal comfort range. To verify the effectiveness of the proposed variable duty cycle control method, the case study is performed using the historical data on Sep. 7th, 2001 acquired at a classroom in Seoul and the obtained results are compared with the fixed duty cycle control method.

• Korean Journal of Hydrosciences
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• 제8권
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• pp.125-136
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• 1997

The simulation techniques of hydrologic data series have develped for the purposes of the design of water resources system, the optimization of reservoir operation, and the design of flood control of reservoir, etc. While the stochastic models are usually used in most analysis of water resources fields for the generation of data sequences, the indexed sequential modeling (ISM) method based on generation of a series of overlapping short-term flow sequences directly from the historical record has been used for the data generation in the western USA since the early of 1980s. It was reported that the reliable results by ISM were obtained in practical applications. In this study, we generate annual inflow series at a location of Hong Cheon Dam site by using ISM method and autoregressive, order-1 model (AR(1)), and estimate the drought characteristics for the comparison aim between ISM and AR(1).

• 한국정보과학회논문지:소프트웨어및응용
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• 제26권1호
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• pp.80-80
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• 1999

As Temporal DataBase Systems(TDBSs) manages both the historical versions and the current version of each data item, a temporal transaction may access more data records than atransaction in traditional database systems. Hence, the concurrency control subsystem of temporaldatabase management system should be able to correctly and efficiently detect actual conflicts amongconcurrent temporal transactions while the cost of detecting conflicts is maintained in low levelwithout detecting false conflicts which cause severe degradation of system throughput.In this paper, Two-Level Conflict Detection(TLCD) scheme is proposed for efficient conflictdetection between concurrent temporal transactions in TDBs. In the proposed TLCD scheme, sincechecking conflict between concurrent temporal transactions is performed at two levels, i, e., logicallevel and physical level, conflicts between concurrent temporal transactions are efficiently and correctlydetected,Furthermore, we also evaluate the performance of the proposed TLCD scheme with those oftraditional conflict detection schemes, logical-level conflict detection scheme and physical-level conflictdetection scheme by simulation approach, The result of the simulation study shows that the proposedTLCD scheme outperforms the previous conflict detection schemes with respect to the averageresponse time.

• 대한예방의학회:학술대회논문집
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• 대한예방의학회 1994년도 교수 연수회(환경)
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• pp.651-657
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• 1994

To assess quantitatively the association between benzene exposure and leukemia, we examined the mortality rate of a cohort with occupational exposure to benzene. Cumulative exposure for each cohort member was estimated from historical air-sampling data and, when no sampling data existed, from interpolation on the basis of existing data. The overall standardized mortality ratio (a measure of relative risk multiplied by 100) for leukemia was 337 (95 percent confidence interval, 154 to 641), and that for multiple myeloma was 409 (95 percent confidence interval, 110 to 1047). With stratification according to levels of cumulative exposure, the standardized mortality ratios for leukemia increased from 109 to 322, 1186, and 6637 with increases in cumulative benzene exposure from less than 40 parts per million-years (ppm-years), to 40 to 199, 200 to 399, and 400 or more. respectively. A cumulative benzene exposure of 400 ppm years is equivalent to a mean annual exposure of 10 ppm over a 40-year working lifetime; 10 ppm is the currently enforceable standard in the United States for occupational exposure to benzene. To examine the shape of the exposure-response relation, we performed a conditional logistic-regression analysis, in which 10 controls were matched to each cohort member with leukemia. From this model, it can be calculated that protection from benzene induced leukemia would increase exponentially with any reduction in the permissible exposure limit.

• 한국철도학회논문집
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• 제14권2호
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• pp.194-202
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• 2011

사업의 상세설계 정보 획득이 어려워 개략적으로 투자비산정 시에 적용하는 개략산정 기법은 주로 과거의 경험자료를 활용하며, 이 과거 자료를 현재가격으로 전환시킬 때 원가지수법을 적용한다. 그러나 현실적으로 데이터 부족, 복잡한 물가조정방법 등으로 1회성으로 활용하거나 거의 적용하지 않는다. 본 논문에서는 물가조정을 복잡하게 계산하고 있는 고속철도 열차제어설비를 적정 물가지수를 활용하여 단순화된 원가지수로 개략적인 투자비를 산정 할 수 있는 표준적 과정을 제시한다. 또한 그 결과물은 향후 해당설비의 개략산정에 쉽게 활용할 수 있으며, 유사 설비의 실적자료 DB구축 및 전산모델화 하기 위한 기본적인 기준을 제공할 수 있을 것으로 기대한다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.117-129
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• 2009

This paper studied the safety management network system of infrastructure which constructed smart sensors, closed-circuit television(CCTV) and monitoring system. This safety management of infrastructure applied to bridge, cut slop and tunnel, embankment etc. The system applied to technologies of standardization guidelines, data acquirement technologies, data analysis and judgment technologies, system integration setup technology, and IT technologies. It was constructed safety management network system of various infrastructure to improve efficient management and operation for many infrastructure. Integrated safety management network system of infrastructure consisted of the real-time structural health monitoring system of each infrastructure, integrated control center, measured data transmission using i of tet web-based, collecting data using sf ver, early alarm system which the dangerous event of infrastructure occurred. Integrated control center consisted of conference room, control room to manage and analysis the data, server room to present the measured data and to collect the raw data. Early alarm system proposed realization of warning and response within 5 minute or less through development of sensor-based progress report and propagation automation system using the media such as MMS, VMS, EMS, FMS, SMS and web services of report and propagation. Based on this, the most effective u-Infrastructure Safety Management System is expected to be stably established at a less cost, thus making people's life more comfortable. Information obtained from such systems could be useful for maintenance or structural safety evaluation of existing structures, rapid evaluation of conditions of damaged structures after an earthquake, estimation of residual life of structures, repair and retrofitting of structures, maintenance, management or rehabilitation of historical structures.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.301-303
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• 2000

This paper presents Kohonen neural network and wavelet transform analysis based technique for industrial peak load forecasting for the purpose of peak demand control. Firstly, one year of historical load data were sorted and clustered into several groups using Kohonen neural network and then wavelet transforms are adopted using the Biorthogonal mother wavelet in order to forecast the peak load of one hour ahead. The 5-level decomposition of the daily industrial load curve is implemented to consider the weather sensitive component of loads effectively. The wavelet coefficients associated with certain frequency and time localization is adjusted using the conventional multiple regression method and the components are reconstructed to predict the final loads through a six-scale synthesis technique.

• 대한교통학회지
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• 제13권4호
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• pp.5-29
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• 1995

Advanced Traveler Inoformation Systems*ATIS) , as a subsystem of ITS influence the travel choices of dreivers by providing them with historical, real-time and predictive information to supprot travel decisions and consequently improves the speed and quality of travel. For thesuccessul accomplishment of ATIS, the time-dependent variations of traffic in a road network and travel times of vehicles during their journey must be predicted . The purpose of this study is to evaluate the past developments in the dynamic route choice models and to apply the instantaneous dynamic user optimal route choice model. recently formulated with flow propagation constraints by Ran, Boyce and LeBlanc, to the real transportation network of Seocho-Ku in Seoul. As input data for this application, the time-dependent travel rates are estimated and the link travel time function is derived. The modelis validated from three view points : the efficiency of model itself the ability to predict traffic volume and travel time on links, and the optimal traffic control.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2001년도 학술대회지
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• pp.155-162
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• 2001

최근 건설업계에서는 공정과 비용을 통합, 관리 할 수 있는 전산 시스템 구축에 많은 비용과 노력을 투자하고 있는 실정이다. 하지만 현행 내역위주의 실행예산 체계에서는 선진 관리기법의 적용이 매우 어려운 상태로 단순 보고형의 공정관리만을 수행하고 있는 실정이다. 이를 개선하기 위해 그 동안 공정과 원가를 통합하기 위한 많은 연구가 수행되어 부분적으로 그 성과가 있었으나 대부분 내역중심의 실무한계를 극복하지 못하였다. 이와 더불어, 프로젝트산업의 전형인 건설공사의 고유의 특성에 의해 실적 정보의 축적 및 Feed back이 매우 어려워 과거 실적 자료의 활용 수준이 매우 떨어지고 있다. 그 결과, 공사 초기 관리기준 설정에 많은 시간과 노력이 소모되고 있으며, 생성된 정보의 체계적 관리가 이루어지고 있지 못하다. 따라서, 렬 연구는 건설실무에서 시도되어 왔던 공정과 원가의 통합관리 시스템에서 발생하였던 실무상의 문제를 보완한 통합공사관리시스템을 제안한다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2002년도 학술대회지
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• pp.123-130
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• 2002

건설공사 관리프로세스 및 관리체계는 건설공사를 성공적으로 수행하는데 필수적인 요소이다. 이러한 공사관리체계는 건설공사를 계획${\cdot}$관리함에 있어서 일정, 비용, 성과측정, 현금흐름(cash flow)예측 등의 업무체계가 통합 또는 연계될 때, 효과적인 관리도구로 활용할 수 있으며, 이는 건설공사에 대한 정확하고 신속한 의사결정을 도모하고 관리의 효율성을 증대시킬 수 있다. 이를 위해 우리나라 건설업계에서는 건설공사의 수행과정을 효과적으로 계획하고 통제, 관리한 수 있도록 업무프로세스를 혁신하고, 이를 지원하는 공사관리시스템의 구축에 많은 시간과 노력을 기울이고 있다. 본 연구에서는 건설공사를 효과적으로 계획, 관리하여 업무프로세스의 투명성을 확보하고 비용효과를 증대시키기 위한 방안의 일환으로 구축되고 있는 공사관리시스템의 개발 동향과 기능적 특징을 비교 분석하고, 구축된 공사관리시스템이 유효하게 기능할 수 있도록 하기위한 현안과제와 대응방안을 제시하고 있다.