• 한국GIS학회:학술대회논문집
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• 한국GIS학회 2010년도 춘계학술대회
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• pp.175-179
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• 2010

본 연구의 목적은 캠퍼스 내 설치된 CCTV의 현황과 설치환경을 파악하고, CCTV의 설치위치 주변 환경 기계적 성능 동을 고려하지 않을 때 발생하는 방범용 CCTV의 설치 및 운용에 문제점을 평가하는데 있다. CCTV의 설치 위치 평가를 위해 네트워크 분석을 활용 했으며, CCTV의 설치환경 분석을 위해서 기계적재원의 확인과 가로등 및 보안등의 조도측정이 이루어졌다. 그 결과 경북대학교 CCTV의 문제점은 크게 학생들의 보행패턴과 무관한 곳에 설치된 지역, 야간 촬영 시 요구되는 조도가 부족한 지역에 설치되어 있음이 확인 되었고, 44대의 CCTV 중 25대만이 범죄 예방이라는 소기의 목적을 위해 활용될 수 있음이 확인되었다.

• 전기학회논문지
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• 제64권3호
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• pp.357-364
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• 2015

The power system configuration is changed to solve increasing power demand. This changes in power system configuration with mesh-, network grid generate the problem of fault current increase. Superconducting fault current limiter (SFCL) has been expected the one of the solutions to solve this problem. And there has already been reported much to the application and research of SFCL in the power distribution system. However, the application and research of SFCL are insufficient in a transmission power system. Also, the fault current limiting effect by the SFCL varies with installation location of SFCL. Therefore, this paper constructed the power transmission system through experiment and analyzed installation location method of SFCL using the current rate of each circuit breaker (CB) according to fault location.

• 한국가시화정보학회지
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• 제20권2호
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• pp.21-27
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• 2022

Air purifiers can be placed where the air cleaning is required, making it easy to manage indoor air quality. The position of the air purifier affects the indoor airflow pattern, resulting in different air cleaning efficiency. Many efforts and strategies have been examined through numerical simulations and experiments to find the proper location of the air purifier, but problems still remain due to the various geometrical indoor spaces and arrangements. Herein, we develop an artificial intelligence model to predict the performance of an air purifier depending on the installation location. To obtain the training data, numerical simulations were performed on the different locations of the air purifiers and airflow patterns. The trained artificial intelligence model predicted the air exchange performance depending on the installation location of the air purifier with a prediction accuracy of 92%.

• Ocean Systems Engineering
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• 제8권3호
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• pp.313-327
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• 2018

Meeting the touchdown point (TDP) target box is one of the challenges during catenary riser installation, especially for deep water or ultra-deep water riser systems. TDP location mismatch compared to the design can result in variation of riser configuration, additional hang-off misalignment, and extra bending loads going into the hang-off porch. A good understanding of the key installation parameters can help to minimize this mismatch, and ensure that the riser global response meets the design criteria. This paper focuses on investigating the potential factors that may affect the touchdown point location, and addressing the challenges both in the design stage and during installation campaign. Conventionally, the vessel offset and current are the most critical factors which may affect the TDP movement during installation. With the offshore exploration going deeper and deeper in the sea (up to 10,000ft), other sources such as the seabed slope and seabed soil stiffness are playing an important role as well. The impacts of potential sources are quantified through case studies for steel catenary riser (SCR) and lazy wave steel catenary riser (LWSCR) in deep water application. Investigations through both theoretical study and numerical validation are carried out. Furthermore, design recommendations are provided during execution phase for the TDP mismatch condition to ensure the integrity of the riser system.

• 대한교통학회지
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• 제26권1호
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• pp.7-14
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• 2008

교통신호기의 설치목적 중 하나는 교통신호기를 통해 차량의 이동을 명확히 규제하여 교통사고를 사전에 방지하는데 있다. 하지만, 부적절한 신호기 위치로 인해 교차로에 접근하는 운전자가 안전운행에 필요한 행태를 나타내지 못한다면, 교통 안전도를 높이기 위한 방안으로 현장상황에 적합한 설치기준 또는 권고사항이 현장조사 및 분석을 통해서 제시되어야 할 필요가 있다. 이러한 배경에서 본 연구는 도심 신호교차로의 신호기 위치가 교차로에 접근하는 운전자의 운전행태에 미치는 영향을 분석하였다. 분석한 결과, 신호기 위치는 딜레마존을 형성하는 운전자의 감속시작지점과 접근속도에 따른 딜레마존 분포에 영향을 미치며, 더욱이 딜레마존 안전율과 밀접한 관계가 있는 것으로 나타났다. 따라서, 본 연구는 신호교차로의 교통안전도를 향상하기 위한 대안으로 교통신호기를 정지선 근처로 이설 또는 설치하는 방안을 다룬 신호기 설치운영 권고안을 제안하여 현장 활용도를 제고하고자 하였다.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2003년도 학술대회논문집
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• pp.107-109
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• 2003

This paper studies islanding detection distributed of distributed generation(DG). The study of islanding detection has been disconnected DG when power islanding was detected but fault type wasn't distingish. Nearby feeder fault the fault of feeder that not interconnected DG, is a little affect DG and distribution system. Therefore DG not need to disconnect distribution system. We studied islanding detection algorithm considering fault location.

• 조명전기설비학회논문지
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• 제27권12호
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• pp.38-43
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• 2013

In this paper, the location measurement method for the reliable location data using ultrasonic sensors is proposed for the dimming control of the LED flat lamp. The measurement errors depending on the reflection angle of the object have to be considered to obtain the reliable location data in the ultrasonic sensors. In the experiment, the cause of the measurement errors depending on reflection angle is analyzed and velocity change of ultrasonic wave depending on reflection angle is measured. And the location measurement method depending on velocity change of ultrasonic wave is proposed. From the results, the average absolute deviation of the x-coordinates was 1.47cm when the location measurement method was considered, and it was closer to the true values than the average absolute deviation of the x-coordinates which was 5.89cm without regard to the reflection angle.

• 조명전기설비학회논문지
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• 제26권2호
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• pp.51-60
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• 2012

An improved method for detecting fault distance in overhead transmission lines is described in this paper. Based on single-ended measurement, propagation theory of traveling waves together with the wavelet transform technique is used. In estimating fault location, a simple, but fundamental method using the time difference between the two consecutive peaks of transient signals is considered; however, a new method to enhance measurement sensitivity and its accuracy is sought. The algorithm is developed based on the lattice diagram for traveling waves. Representing both the ground mode and alpha mode of traveling waves, in a lattice diagram, several relationships to enhance recognition rate or estimation accuracy for fault location can be found. For various cases with fault types, fault locations, and fault inception angles, fault resistances are examined using the proposed algorithm on a typical transmission line configuration. As a result, it is shown that the proposed system can be used effectively to detect fault distance.

• 조명전기설비학회논문지
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• 제28권4호
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• pp.36-41
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• 2014

Most faults that occur on transmission lines are caused by extreme weather with lightning storms in the distance. These are not only prolongs the time of removing and recovering, but also increases economical damages. If faults can be precisely located, maintenance crews can reach them quickly, and remove the faults in time. So, the precise locating of the faulted point on a transmission line is very important to improve the system reliability, and decreases economic damages as an inherent consequence of long term outages. Also, fault location methods are becoming of much importance for utilities and research. In this paper, two single-terminal impedance-based fault location techniques will be investigated to show the reliability and evaluated the performance of reactance and Takagi method by using MATHCAD program simulations.

• 국제학술발표논문집
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• The 9th International Conference on Construction Engineering and Project Management
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• pp.145-152
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• 2022

Recently, interest in the precast concrete (PC) construction method has been increasing. The PC construction process consists of i) design, ii) production, iii) transportation, and iv) installation. A PC field manager at the site submits a shipment request form to the factory one to three days before the installation of the PC component. Numerous matters should be considered in writing a shipment request form. Incorrect shipment request forms may cause standby resources, waste of resources, premature work conclusion, or excessive work. These issues can lead to an increase in construction costs, replanning of PC component installation, or rework. In order to prevent such problems, PC component installation should be simulated based on the shipment request form. Accordingly, this study aims to identify factors influencing the operability of shipment request forms for PC construction. To this end, this study derived factors influencing i) initiation of the activity, ii) addition or deletion of activities, and iii) an increase or decrease in the activity execution time. As a result, this study identified flow, the features of PC components, condition of PC components, unloading location, installation location, input equipment and labor, number of anchors, number of supports, weather, strike, and accident. Further studies should verify the factors derived in this study based on focus group interviews.