• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.292-298
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• 2010

Recently, with the beginning of the commercial operation of high-speed railway, there have been a number of changes in track structure fields. Also, it is expected that the development and introduction of new technology will be increased afterwards. However, it accompanies a lot of risk to install new track structures of which performance and safety are not verified on permanent ways with high traffic density. Therefore, to minimize the risk and enhance the adoption of new technology, it is required to develop a systemic verification system for track structure. To do this, in this paper, main contents of a draft of guidelines for track structure verification, and main issues in debate such as criteria and method for verification, test conditions and test periods are discussed. Also, a process to choose a most appropriate one for a specific project out of proven track structures by the above verification system, the selection process by the technical investigation committee and the VE process to analyze the economical and maintenance aspects based on LCC concept in Korea Rail Network Authority is introduced.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2003년도 춘계학술발표회 논문집
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• pp.409-414
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• 2003

In the beginning of the 21s1 century, the world has been making rapid progress and changed all over the areas. Like the rest, as all domiciliary circumstances for a local development have changed, the continuous development considered environmental view has been accounted as much compared with the high growth-oriented development based on the efficiency so far. As the volume of traffic in urban community increases, the environmental load enlarges inevitably. Particularly, the excess and deficiency problems for all sorts of traffic facilities, like the shortage of parking lots continue to happen in proportion to the increase in traffic. For a design to solve these problems, introduction of the Geographic Information System; GIS applied widely over various fields become necessary. In this research, the supply-demand situation in urban areas is observed. The application of GIS for the purpose of the improvement of parking lot management technique to control effectively facilities related to parking lot in the city brings promoting the efficiency of business data inquiry, data management data correction and so on through graphic and non-graphic database for every kind of draft data, record and register data. The graphic users interface to support effective decision-making is applied for the improvement of work in this study. This research also suggests the way to utilize common database considered linkage with sub-systems related existing urban information system by developing the parking lot management system.

• Journal of Biosystems Engineering
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• 제14권4호
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• pp.221-228
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• 1989

A data acquisition system was designed to measure the forces on a rolling coulter in three coordinated directions, angular velocity of the coulter and travel speed of a soil bin. The data acquisition system consisted of a dynamometer, speed transducers, a signal conditioner, an inter-face board, an Aim-65 microcomputer and a digital data recorder. Strain gages were attached on the surface of the dynamometer and connected to form three Wheatstone bridges, which measure the draft force, the vertical force and the side force on the coulter. An interaction among three dimensional forces was found during the calibration. A matrix procedure was used to correct the forces for this interaction. Rotary shaft encoders were mounted on the coulter and on the soil bin drive to measure the angular velocity of the coulter and the travel speed of the soil bin. The angular velocity and the travel speed were computed by counting the number of pulse signals from the rotary shaft encoders every 0.2 second. The digital signals from the rotary shaft encoders were connected to counters and the analog signals from the dynamometer, after passing through the signal conditioner, were connected to the A/D converter. The microcomputer programs, written in assembly language, were developed to read signals from the transducers, convert them to actual unit, display them upon request and record them on a sigital tape every 0.2 second.

• 한국태양에너지학회 논문집
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• 제27권1호
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• pp.83-90
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• 2007

Apartment balcony has been indiscreetly remodeled since the government permitted remodeling on January 2006. But remodeled balcony has a few problems such as increase of heating energy, surface condensation and cold draft. The reason of thermal problem is mainly caused by the window system in a extended balcony. The purpose of this study is to analyze heating and cooling energy and propose the efficient window types for the extended balcony area of a apartment building. 4 types of window system which have fairly high U value in Korea are investigated as follows ; double clear glass, double low-e glass, triple clear glass and triple low-e glass. Comparing double clear 91ass with double low-e glass, triple clear glass and triple low-e glass, simulation results show that 10%, 7% and 15% saving of total primary energy can be expected.

• 한국군사과학기술학회지
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• 제15권2호
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• pp.177-185
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• 2012

Corrosion currents flow through the seawater due to the different electrochemical potential between a hull and a propeller under the draft line of ship. Additionally, in order to protect the hull and other sensitive anodic parts of the ship from corrosion, the corrosion protection system, called impressed current cathodic protection(ICCP) equipment has been installed in most naval ships. Those currents could be harmful to the electromagnetic silencing of the naval ship because sea mines are triggered by even a feeble field value. In this paper, we described electric and corrosion related magnetic fields by ship's galvanic corrosion and a corrosion protection system, and prediction results of electric and corrosion related magnetic fields at any depth for the model ship.

• 한국해양공학회지
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• 제27권5호
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• pp.43-50
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• 2013

In the present investigation, the hydrodynamic characteristics of a vertically floating hollow cylinder in regular waves have been studied. The potential theory for solving the diffraction and radiation problem was employed by assuming that the heave response motion was linear. By using the matched eigenfunction expansion method, the characteristics of the exciting forces, hydrodynamic coefficients, and heave motion responses were investigated with various system parameters such as the radius and draft of a hollow cylinder. In the present analytical model, two resonances are identified: the system resonance of a hollow cylinder and the piston-mode resonance in the confined inner fluid region. The piston resonance mode is especially important in the motion response of a hollow circular cylinder. In many cases, the heave response at the piston resonance mode is large, and its resonant frequency can be predicted using the empirical formula of Fukuda (1977). The present design tool can be applied to analyze the motion response of a spar offshore structure with a moon pool.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.953-958
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• 2006

Perimeter zone has been reinforced by active systems, such as fan-coil units, because it causes an increase in heating and cooling loads, dew condensation in winter, or discomfort with cold-draft to residents in buildings, through poor insulation by light-weighed skin due to progressing multi-storied buildings and skyscrapers. However, because these active systems raise Its capacity so that fossil fuel is used as much as they are added, and ultimately, greenhouse effect is urged, we proposed BIPV system functioned as solar collector which can substitute active system. As an early stage, heat balance equation in steady-state by Fortran was used not only for pre-heating effect and electric power capacity during the day in winter, but also for electric power capacity during day in slimmer and sky radiation effect during night in summer. Especially, we should have considered shading on PV, since even a little bit of it makes the efficiency too low for the PV to work. Still, when the flux of pre-heated air was increased to make air-barrier, its temperature was not enough to make it because the speed of heat exchange was too fast to warm up the air, thus the capacity to meet the condition was evaluated, and electric power from PV was made used for it.

• Human Ecology Research
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• 제62권2호
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• pp.197-216
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• 2024

The dual aims of this study were i) to explore the effectiveness of an assessment method that can measure the competencies learned through high school home economics and ii) develop a competency-based assessment framework for high school home economics, including components of competency-based assessment, item development system, and other elements. The study involved the following stages: literature analysis, draft development, concretization, validity verification, and final version. Based on the results of the literature analysis and expert deliberation, a competency-based assessment framework for high school home economics was developed which comprised three dimensions: 'core idea' × 'process' × 'context and value'. Based on this, an item analysis table was presented to systematize various activities for the competency-based assessment of high school home economics, following which a holistic rubric suitable for competency assessment tasks was proposed by referring to the newly developed 'process' dimension assessment criteria. This study is significant in that it is the first to propose a competency-based assessment framework that systematically presents a variety of assessment activities. These will facilitate the development of assessment standards and tools that teachers can refer to or trust in the changing school environment due to the introduction of the standard-based assessment system based on a high school credit system, and the guarantee of a minimum achievement level.

• 한국가스학회지
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• 제7권1호
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• pp.24-27
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• 2003

본 연구에서는 국내 석유화학공장에서 운전되고 있는 CDU plant heater, NCC plant heater, CO plant Heater, aromatic plant heater 등 15개 plant heater를 대상으로 조사하였으며, 세부 내용으로는 heater 사고 예방을 위한 공정운전 표준, alarm 작동시 조치 및 setting 변경, 시운전 점검사항, interlock system 분석, interlock by-pass 운전현황, heater 주요 사고$\cdot$사례 등을 분석하였다. interlock 방지 및 시설개선 대책으로 실시간 monitoring 설치, local 압력계 및 온도계추가설치, 초기 운전시 점검방법, interlock by-pass 관리, 오작동 계기 sensor maker 변경, 운전 mode 변경시 주요 현장확인사항, DCS alarm 관리방법 등을 제시하였다. heater interlock에 관련되는 국내외 연구자료가 거의 없어서 주로 석유화학업체 운전 절차서, 공정trouble 일지, 부서장 및 현장 운전원의 의견을 반영하여 연구하였다. 연구의 결과에 따라 interlock 방지 및 시설개선 대책을 운전 절차서에 반영한다면 interlock으로 인한 사고를 크게 줄일 수 있을 것으로 기대된다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2006년도 춘계종합학술대회
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• pp.577-580
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• 2006

인터넷의 급속한 확산은 디지털 콘텐츠 시장을 활성화 시켰으나 무분별한 불법 복제와 유통으로 디지털 콘텐츠 시장이 위축되고 있다. MPEG(Moving Picture Experts Croup)은 이러한 문제를 해결하기 위하여 MPEG-21 Multimedia Frameworks를 제안하였다. IPMP(Intellectual Property Management and Protection)는 MPEG-21 Multimedia Frameworks의 세부 분야로 디지털 콘텐츠가 생성, 전달, 소비를 거치는 과정에서 디지털 콘텐츠를 안전하게 다루기 위한 표준을 정의하는 것으로 FCD(Final Committee Draft) 단계까지 표준화가 이루어졌다. 따라서 디지털 콘텐츠의 저작권을 보호 관리하기 위하여 IPMP의 최신 표준화 내용을 적용한 시스템 개발이 요구되었고, 이에 따라 디지털 콘텐츠를 보호 관리하는 시스템을 크게 저작 서버, 틀 서버, 라이센스 서버, 소비 서버의 네 개 구조로 구분하였다. 이에 본 논문에서는 라이센스 서버로부터 전송된 콘텐츠의 정보가 담긴 REL(Rights Expression Language) 문서 파싱 기능과 워터마크가 적용된 콘텐츠에 대한 MPEG-21 IPMP 기반의 메타데이터 생성 및, Remuxing 과정을 거친 데이터를 암호화하여 소비 서버로 전송하는 저작 시스템에 대하여 설계 및 구현하였다.