• KIEAE Journal
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• 제13권6호
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• pp.105-111
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• 2013

This study aims to suggest the PV lightshelf and to evaluate the power performance of the photovoltaic systems easily mounted on the windows. For the study, the suggested systems consist of two parts as fixed and movable PV modules. Also, tempered glass and polycarbonate are used on the surface protection materials for solar cells of PV lightshelf. By using polycarbonate, the weight of PV lightshelf is lighter about 20%. The field tests are performed for five days by using real size models. The voltage, current and electric powers are measured as basic performances of PV lightshelf. Also, the irradiation, brightness and module surface temperature are measured as outside conditions. As results, the power performance of tempered glass PV lightshelf shows about 11(%) higher thant that of polycarbonate PV lightshelf. And the power performance shows about 5(%) higher in a horizontal system. This results could be used to develop the effective PV lightshelf in next study.

• 한국기계가공학회지
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• 제2권2호
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• pp.67-74
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• 2003

This paper presents the development of the Inspection machine for SMD mounted on cream solder of PCB. There are mounting errors of SMD such as misalignment, missing part, wrong orientation, wrong polarity and so on. The main hardware of the system consists of a machine vision part and a motion control part. Operating software has been developed in GUI environment to help user convenience. The Inspection Jobs consist of two procedures, that is, creation of the inspection reference data and automatic inspection. The Inspection reference data has a tree structure of linked list including PCB information, blocks, components, windows, and inspection methods. This paper presents versatile inspection methods which include a section length method, a projection method and histogram method. Therefore, user can choose the suitable procedure for various components. Finally, the automatic Inspection procedure using the reference data checks the mounting errors of components.

• 설비공학논문집
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• 제15권7호
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• pp.557-562
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• 2003

Flue gas from apartment heating gas boiler is exhausted outside through an exhaust duct mounted horizontally in a vertical row on the wall. The flue gas includes nitrogen-oxides (NOx) and carbon monoxide. To investigate the possible entrainment of the flue gas into the apartments through the windows, a large eddy simulation (LES) based numerical method is utilized. Distribution of the velocity intensity and temperature around the exhaust ducts is presented for three numerical parameters: exhaust velocity, temperature of the flue gas, and exhaust duct length. The flow field visualized with particles inserted at the ends of the ducts is also presented. The results clearly show that the exhausted flue gas may flow into the apartments when the windows are open.

• 대한용접접합학회:학술대회논문집
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• 대한용접접합학회 2000년도 특별강연 및 춘계학술발표대회 개요집
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• pp.310-312
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• 2000

In welding, there is much dangerous element. Workers who are exposed to working field of welding may be infected with industrial diseases. To solve these problems, many studies has been carried out. It is a good method to make welding automation in the distance and internet makes it possible. If internet is used, welding can be carried out without the limitation of time and place. On this study, welding by using internet is studied. By using internet, computer which has interface with welding machine is connected to computer in the distance and welding is carried out with the signal of computer in the distance. Basically the connection of computers is made by two program-Server and client windows program-which have functions which are needed for control of XYZ table and welding machine. Through these program, the motion of welding torch which was mounted on XYZ table, the starting and ending of welding is controlled and monitored with a camera. Also, signal-welding current and arc voltage-is measured and displayed.

• 유공압시스템학회논문집
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• 제8권2호
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• pp.1-7
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• 2011

An inverted pendulum mounted on a cart and actuated by a hydraulic servo cylinder was designed and built. Position information of the cart was acquired via a potentiometer and a angle of the pendulum was sensed by an incremental encoder. These were collected by a DAQ board and processed through the Real-Time Windows Target software(included in simulink). A simulink graphical program was implemented as a controller of the hydraulic system that governed the motion of the cart in order to maintain vertical balance of the inverted pendulum. The purpose of this study is to develop an electro-hydraulic inverted pendulum system for a modeling and controling the intrinsic unstable system. The simulation results were compared with the experimental and verified.

• 천문학회보
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• 제46권2호
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• pp.78.3-79
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• 2021

Coronal Diagnostic Experiment (CODEX) is a diagnostic coronagraph developed by the Korea Astronomy and Space Science Institute and the NASA Goddard Space Flight Center (GSFC) to be deployed in 2023 on the International Space Station (ISS). It is designed to obtain simultaneous measurements of electron density, temperature, and velocity in the 2.5 - 10 solar radius range using multiple filters. The filters are mounted in two filter wheel assemblies (FWAs), which have five filter positions each. One position of each FWA is occupied by windows, and remaining eight positions are occupied by three bandpass filters for temperature, two bandpass filters for velocity, one Ca II H filter for F-corona, one broadband filter for fast imaging and density, and one neutral density (ND) filter for direct Sun viewing and safety.

• 정보보호학회논문지
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• 제21권4호
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• pp.89-100
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• 2011

그간 디지털 포렌식의 활성 시스템 분석 분야의 한 화두는 물리 메모리 이미지 분석이었다. 물리 메모리 분석은 프로세스를 은닉을 하더라도 그 데이터를 물리 메모리에서 확인할 수 있고 메모리에 존재하는 사용자의 행위를 발견할 수 있어 분석 결과의 신뢰성을 높이는 등 디지털 포렌식 분석에 큰 도움이 되고 있다. 하지만 메모리 분석 기술 대부분이 윈도우 운영체제 환경에 초점이 맞추어져 있다. 이는 분석 대상의 다양성을 고려하였을 때 타 운영체제에 대한 메모리 분석이 필요하게 되었음을 의미한다. Mac OS X는 윈도우에 이어 두 번째로 높은 점유율을 가진 운영체제로 부팅 시 커널 이미지를 물리 메모리에 로딩하면서 운영체제가 구동하고 주요 정보를 커널이 관리한다. 본 논문은 Mac OS X의 커널 이미지가 저장하고 있는 심볼 정보를 이용한 물리 메모리 분석 방법을 제안하고, 제안한 내용을 토대로 물리 메모리 이미지에서 프로세스 정보와 마운트된 장치 정보, 커널 버전 정보, 외부 커널 모듈정보(KEXT)와 시스템 콜 목록 정보의 추출 방법을 보인다. 추가적으로 사례 분석을 통해 물리 메모리 분석의 효용성을 입증한다.

• 한국멀티미디어학회논문지
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• 제14권8호
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• pp.1041-1049
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• 2011

사회의 발전과 함께 사회 기반을 구성하는 시설물들의 관리에 대한 연구가 지속되고 있으며, 사회 각 분야에서는 다양한 아이디어를 바탕으로 새로운 시스템을 구축하여 왔다. 그 중 상수도 관망 관리를 위해서 현재 시공되어 운영되고 있는 RTD-1000은 누수 및 파손 등을 원격으로 감지하는 기기로써, PC 기반의 시스템 형태를 가지고 있다. 하지만 PC 기반에서 오는 리소스 소비, 발열, 소비전력이 크다는 취약점이었다. 본 논문에서는 RTD-1000의 취약점을 보완한 개량된 시스템인 RTD-2000을 제안한다. 이 시스템은 WinCE 기반의 ARM9 개발 킷과 LCD가 제거된 TDR만으로 설계 및 구현되었다. RTD-1000에 탑재되었던 윈도우 기반의 각종 감지 프로그램들은 ARM9 기반의 전용 임베디드 S/W로 대체하였고, 성능 비교를 위하여 시뮬레이션 및 평가를 수행하였다.

• Nuclear Engineering and Technology
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• 제31권4호
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• pp.423-431
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• 1999

A radiotracer technique has been developed to monitor the rotational movement of two piston rings in one cylinder during engine operation. The rings were labeled with two different kinds of radioisotopes, i.e. $^{60}$ Co and $^{192}$ Ir, for identification of the top ring from the second ring. The radiotracers were implanted in a small hole bored on the inner side of each piston ring. The rings were installed in a single cylinder hydrogen engine and three Nal scintillation detectors were mounted around the engine block to measure the gamma radiation. The angle of ring-gap orientation was determined from the radiation counts measured with the three detectors during engine operation. Two windows (upper window for $^{60}$ Co and lower window for $^{192}$ Ir) were set on each ratemeter to count radiation from the two isotopes separately. Procedure to convert the radiation counts to the position of the ring gap was established. With the software programmed with MS-Visualbasic, radiation counts were compared with the reference responses that were measured at angular intervals of 10$^{\circ}$for each piston ring in advance of the experiment. The result was used for the evaluation of the relationship between the orientation of ring-gaps and oil consumption. It was found that an increase in the oil consumption rate of a specific operation condition was closely related to the relative phase angle of the two piston rings.

• Journal of Biosystems Engineering
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• 제24권2호
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• pp.159-166
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• 1999

A system to extract continuously the real 3-D geometric fearture information from 2-D image of an object, which is fed randomly via conveyor has been developed. Two sets of structured laser lightings were utilized. And the laser structured light projection image was acquired using the camera from the signal of the photo-sensor mounted on the conveyor. Camera coordinate calibration matrix was obtained, which transforms 2-D image coordinate information into 3-D world space coordinate using known 6 points. The maximum error after calibration showed 1.5 mm within the height range of 103mm. The correlation equation between the shift amount of the laser light and the height was generated. Height information estimated after correlation showed the maximum error of 0.4mm within the height range of 103mm. An interactive 3-D geometric feature extracting software was developed using Microsoft Visual C++ 4.0 under Windows system environment. Extracted 3-D geometric feature information was reconstructed into 3-D surface using MATLAB.