• 대한디지털의료영상학회논문지
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• 제9권2호
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• pp.17-21
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• 2007

The purpose to recognize change of average pixel value of acquisition image by control panel's density and right set up method of speed (sensitivity) and exposure dose(mAs) change that dose in purpose digital flatpanel-detector. X -ray generator DHF-158H2(Hitachi, Japan). Detector CXDI 4OG(Canon, Japan), 12 : 1 grid and exposure ray 135 kVp, 250 mA, 10 ms. focus-detector distance 180 cm and used AEC mode. DICOM reflex analysis program used image J that is digital reflex analysis program that offer in United States America National Health Center(National Institutes of Health : NlH) phantom used chest phantom(Anthromorphic : Flukebrome.medicaI USA). An experiment chest phantom that consist by formation equivalence material use because density value( -3${\sim}$+3) in X-ray control panel and seep that is speed step(slow, medium, fast) each control experimentalize. image analysis reflex neted through an experiment using image j each image compare. These was change in dose according to slow, medium, fast and density's change in an experiment result. According to detector sensitivity and density condition set, dose was relationship dissimilarity 500% from 200%. The dose came highest when is density +3 to slow. and dose more increases gray scale's extent could know that rise. Could know whether how equipment set is important through this experiment. cause of disease which change by digital radiography system forward is thought to increase more, it is considered that suitable education by this and continuous interest about equipment need absolutely.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 춘계학술대회논문집
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• pp.18-21
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• 1999

In this study in order to make doubly-curved sheet metal effectively a sheet metal forming process has been developed by adopting the flexibility of the incremental forming process and the principle of bending deformation which causes slight deformation to thickness The developed process is an unconstrained forming process with no holder. For this study the experimental equipment is set up with the punch-set which consists of two pairs of lower support-punches and one upper center-punch. In the experiments using aluminum sheet it is found that the curvature of the formed sheet metal is determined by controlling the distance between supporting punches in pairs and the forming depth of the center-punch. and the edge-forming method is proposed for forming the sheet metal into the balanced shape. The equation using process variables such as the distance between supporting punches in pairs and the forming depth of the center-punch is proposed for the prediction of the radii of curvatures of the formed shape and it is corrected by the experimental results and the FEM simulation results about whether springback takes place. It is found that according o the simulation there is a certain set of the distance between a pair of supporting punches and the forming depth of the center-punch which causes a little springback. It is thus shown that the radii of curvatures of the formed sheet metal can be predicated by the corrected equation unless significant springback occurs.

• Journal of Biosystems Engineering
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• 제30권4호
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• pp.220-228
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• 2005

This study was conducted to investigate the main factors that contain a rotating velocity ratio between wheel and conveyor belt, a tilt angle of conveyor belt and a rotating velocity of a dick cutter for mechanization of Chinese leek harvest. In the survey on the cultivation of Chinese leek, row spacing of 350 m and cutting height of 10 mm from the ground were set up for field tests. Test equipment was designed to cut, pick up and convey Chinese leek one row by one row. From the results of material tests, pick-up height of conveyor belt was set up at $60\~90m$ from the bottom, and the strain and stress at rupture of Chinese leek was 0.487 m/m and 0.01078 MPa. An elastic coefficient of the rubber (Neoprene) of conveyor belts was 1.1077 under the strain of 0.3 nym. from the results of field tests, the tilt angle of conveyor belt was the range of $25^{\circ}\~30^{\circ}$ under consideration far space of container, the velocity ratio between vehicle and conveying belt was 1 to 2.4~1.7 at 0.1~0.3 m/s of vehicle, and optimum rotating velocity of the disk cutter was 34.8 m/s or more under consideration for soil friction.

• 해양환경안전학회지
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• 제24권6호
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• pp.654-661
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• 2018

본 논문에서는 마리나 항의 상하가 시설 및 장비의 형태를 분석하고 마리나 이용 대상 선박을 기준으로 기 설치된 마리나의 상하가 시설(리프트 피어)과 장비(마린 모바일 리프트)에 대한 분석을 통해 상하가 시설 및 장비의 설치기준을 마련했다. 국내에서 운항중인 선박 총톤수에 따라 요구되는 리프트 피어의 내부 간격은 35톤 선박은 5.50 m, 50톤 선박은 6.20 m이며, 이를 상하가하기 위한 마린 모바일 리프트의 내측 폭은 35톤 선박은 6.10 m, 50톤 선박은 6.80 m가 필요하다. 국내 마리나에 설치된 리프트 피어는 목표한 선박을 인양할 수 있는 곳은 2곳으로 나타났으며, 그 외 다른 마리나의 리프트 피어 내부 간격은 0.35 ~ 0.50 m가량 좁았다. 또한 운용 중인 마린 모바일 리프트 중 목표한 선박을 상하가하기 위해 필요한 내측 폭을 확보한 장비는 2개로 나타났으며, 그 외 마린 모바일 리프트 내측 폭이 0.3 ~ 0.6 m가량 부족했다.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2008년도 정기학술발표대회 논문집
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• pp.794-799
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• 2008

건설 가설재 성능검정제도의 전환기에 들어서 주요 가설재들의 성능검정을 평가하고 선진국의 관련 체계와 비교하여, 안전인증제를 통해 새로운 건설공사용 가설재들의 인증제도를 제안하고자 한다. 현재의 성능검정제도는 1992년에 시작되어 2003년에 재 개정되면서, 3년마다 재 검정을 받도록 하고 있다. 그러나 제조능력을 향상시키지 못하고 업체 간 가격경쟁의 심화로 인해 대부분 같은 형태, 기능의 제품만을 양산하고 있는 실정이다. 기존 성능검정제도에서 안전인증제로의 전환은 보다 체계적인 심사방법 및 품질관리 시스템을 포함하고 있으며, 건설 환경 변화에 대응할 수 있는 다양한 요구사항에 맞춘 규격을 제시할 수 있도록 하고 있다. 안전인증제를 통한 건설공사의 가설재는 의무인증대상과 임의인증대상으로 나누어지며, 종전보다 제품의 품질과 관리 시스템을 향상시켜줄 수 있을 것으로 기대된다.

• 대한영양사협회학술지
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• 제12권3호
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• pp.264-276
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• 2006

The purpose of this study was to propose HACCP system implementation properly and to secure the food safety of school foodservices in Pohang city since the proper facilities and equipment should be key factors in food safety and production. So this study was designed to evaluate existing equipment in food production area, receiving and dining area, and employee facilities. Questionnaire was mailed to 107 school foodservice dietitians in Pohang area and 97 were responded (90.7% response rate). Approximately sixty percent of foodservices were not available separate receiving or polluted area, fifty one percent were installed screen door for insecticidal and temperature and humidity control, and these environmental conditions were hard to keep kitchen dry and sanitary condition. Usually public schools were better equipped than private schools. Forty three percent of school foodservice had initial use of non-foodservice, opened before 1994, and thirty three percent of elementary school foodservice. Among employee facilities, hand washing sanitation stand was prepared seventy nine percent (78.9%) of school foodservices. Dietitians chose outworn equipment and facilities (30.9%), difficulties of maintaining standard temperature and humidity for foodservice (20.6%), lacking separate receiving or polluted area (13.4%), indirect contamination of water hoss (10.3%), and lacking employee facilities (10.3%) as critical points to correct in school foodservice. Therefore governmental regulating agencies must review and approval of plans prior to new construction or extensive remodeling of school foodservice facilities. In addition to these requirement, plan must be set-up step by step to implement HACCP system properly.

• Geomechanics and Engineering
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• 제4권4호
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• pp.251-262
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• 2012

Triaxial tests are essential to estimate the shear strength properties of the soil or rock. Normally triaxial tests are carried out on samples of 38 mm diameter and 76 mm height. Granular materials, predominantly used in base/sub-base construction of pavements or in railways have size range of 60-75 mm. Determination of shear strength parameters of those materials can be made possible only through triaxial tests on large diameter samples. This paper describes a large diameter cyclic triaxial testing facility set up in the Geotechnical Engineering lab of Indian Institute of Science. This setup consists of 100 kN capacity dynamic loading frame, which facilitates testing of samples of up to 300 mm diameter and 600 mm height. The loading ram can be actuated up to a maximum frequency of 10 Hz, with maximum amplitude of 100 mm. The setup is capable of carrying out static as well as dynamic triaxial tests under isotropic, anisotropic conditions with a maximum confining pressure of 1 MPa. Working with this setup is a difficult task because of the size of the sample. In this paper, a detailed discussion on the various problems encountered during the initial testing using the equipment, the ideas and solutions adopted to solve them are presented. Pilot experiments on granular sub-base material of 53 mm down size are also presented.

• 한국진공학회지
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• 제21권2호
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• pp.106-112
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• 2012

본 연구에서는 톨루엔 등의 휘발성 유기물의 흡착량을 정성, 정량적으로 연구할 수 있는 새로운 장비를 구축하였으며, 이를 이용하여 기존의 탄소를 기반으로 하는 다양한 흡착제와 원자층 증착으로 만든 $TiO_2$ 박막구조의 톨루엔 흡착에 대한 연구를 진행하였다. $TiO_2$ 박막구조의 흡착제가 기존의 탄소기반 흡착제보다 톨루엔 흡착량이 뛰어난 것을 입증하였으며, 이는 원자층증착으로 제조한 $TiO_2$ 박막 표면의 높은 농도의 OH 그룹의 높은 톨루엔 친화력과 연관성이 있는 것으로 나타났다. 또한 본장비를 이용하여 가역적인 흡착과 비가역적인 흡착을 구분할 수 있음을 보여주었다.

• 전기학회논문지
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• 제64권7호
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• pp.1130-1136
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• 2015

Most equipments which are used to measure the switching power of the turnout depend on imports. As the data is limited to the measurements of the switching power, it is said that the equipment is insufficient to check the errors of the turnout and the electrical point machine, and set up the data for operating and maintenance. We studied not only measurements of the switching power of all turnout being used in domestic but also the development of the turnout performance total analysis equipment which can measure switching time, voltage, and current etc. at the same time. Considering that switching power of the turnout is the most basic element to check the irregularities of the turnout, in this paper, we analyzed the irregularities of the turnout through correlation between switching power of the turnout, voltage, and current of the electrical point machine. Also we performed test in commercial railway line where the turnout of MJ81 type and NS type was installed. And it is said that the test results can be used as basic technologies for ICT based real-time diagnosis and monitoring of the turnout.

• Journal of Power Electronics
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• 제18권3호
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• pp.853-862
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• 2018

Frequency coupling in the phase domain is a recently reported phenomenon for phase locked loop (PLL) based three-phase grid-inverter systems. This paper investigates the mechanism and stabilization method for the frequency coupling to the stability of grid-inverter systems. Self and accompanying admittance models are employed to represent the frequency coupling characteristics of the inverter, and a small signal equivalent circuit of a grid-inverter system is set up to reveal the mechanism of the frequency coupling to the system stability. The analysis reveals that the equivalent inverter admittance is changed due to the frequency coupling of the inverter, and the system stability is affected. In the end, retuning the bandwidth of the phase locked loop is presented to stabilize the three-phase grid-inverter system. Experimental results are given to verify the analysis and the stabilization scheme.