• 한국발생생물학회지:발생과생식
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• 제25권4호
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• pp.293-298
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• 2021

Di(2-ethylhexyl)phthalate (DEHP) could induce metabolic disorders through interfering with thyroid homeostasis. Therefore, we evaluated the effects of short term to environmental relevant doses of DEHP on thyroid hormones. Four week old Sprague-Dawley (SD) rats were treated with vehicle (corn oil), and DEHP 0.75, 7.5, and 150 mg/kg/day. The rats were treated with once daily by oral gavage and were sacrificed with after 1 week. They were measured body weight and relative thyroid weight, serum thyroid hormones and histological changes of thyroid. There was no difference in body weight between the control and DEHP exposed rats. Relative thyroid weight in DEHP 150 mg/kg/day treated group was significantly lower than control. Serum thyroxine levels was decreased in rats exposed to 0.75 and 150 mg/kg/day DEHP. No histological changes were observed in the thyroid of rats administered DEHP compared to control. Exposure to DEHP at environmental relevant levels, even short-term exposure, can cause hypothyroidism in adolescent rats even the exposure period is relative short.

• Journal of information and communication convergence engineering
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• 제15권2호
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• pp.123-130
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• 2017

The early detection of intravenous (IV) infiltration is necessary to minimize the injury caused by the infiltration, which is one of the most important tasks for nurses. For detecting early infiltration in patients receiving invasive vein treatment, bioelectrical impedance was measured using multi-frequency bioelectrical impedance. The impedance decreased significantly at infiltration, and then decreased gradually over time after infiltration. The relative impedance at 20 kHz decreased remarkably at infiltration, and then gradually decreased thereafter. In addition, the impedance ratio increased temporarily at infiltration and then gradually decreased over time. Furthermore, the impedance at each frequency decreased quantitatively over time. This indicates that IV solution leaking from the vein due to infiltration accumulates in the subcutaneous tissues. Moreover, slopes of log Z vs. log f differently decreased with increasing log f, indicating that the impedance exhibits different responses depending on the frequency.

• 디지털융복합연구
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• 제7권4호
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• pp.1-10
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• 2009

Korean e-Government web site has been evaluating as a distinguished government, ranked 5th of the 119 countries in the "Global e-government readiness index report 2005" by UN in 2006. However we have to focus poor rate of utilization in proportion to its high evaluation of e-Government ranking. These reason probably did not reflect the requirements of user to build and operate e-Government web site. In this paper we will provide the important factors to consider to build and operate e-Government web site. For this, we analyze the relative importance for evaluation factors of e-Government web site using AHP(Analytic Hierarchy Process).

• International journal of advanced smart convergence
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• 제8권3호
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• pp.39-45
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• 2019

This paper presents an optical technique for the three-dimensional (3D) shape inspection of micro solder balls used in ball-grid array (BGA) packaging. The proposed technique uses an optical source composed of spatially arranged light-emitting diodes (LEDs) and the results are derived based on the specular reflection characteristics of the micro solder balls for BGA A vision system comprising a camera and LEDs is designed to capture the reflected images of multiple solder balls arranged arbitrarily on a tray and the locations of the LED point-light-source reflections in each ball are determined via image processing, for shape inspection. The proposed methodology aims to determine the presence of defects in 3D BGA shape using the statistical information of the relative positions of multiple BGA balls, which are included in the image. The presence of the BGA balls with large deviations in relative position imply the inconsistencies in their shape. Experiments were conducted to verify that the proposed method could be applied to inspection without sophisticated mechanism and productivity problem.

• 한국의학물리학회지:의학물리
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• 제28권3호
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• pp.83-91
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• 2017

In this work, we investigated the recently proposed phase-contrast x-ray imaging (PCXI) technique, the so-called single grid-based PCXI, which has great simplicity and minimal requirements on the setup alignment. It allows for imaging of smaller features and variations in the examined sample than conventional attenuation-based x-ray imaging with lower x-ray dose. We performed a systematic simulation using a simulation platform developed by us to investigate the image characteristics. We also performed a preliminary PCXI experiment using an established a table-top setup to demonstrate the performance of the simulation platform. The system consists of an x-ray tube ($50kV_p$, 5 mAs), a focused-linear grid (200-lines/inch), and a flat-panel detector ($48-{\mu}m$ pixel size). According to our results, the simulated contrast of phase images was much enhanced, compared to that of the absorption images. The scattering length scale estimated for a given simulation condition was about 117 nm. It was very similar, at least qualitatively, to the experimental contrast, which demonstrates the performance of the simulation platform. We also found that the level of the phase gradient of oriented structures strongly depended on the orientation of the structure relative to that of linear grids.

• 한국전자통신학회논문지
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• 제12권1호
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• pp.139-146
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• 2017

알파고로 촉발된 인공지능에 대한 국민의 관심이 고조되고 있다. 아직 국내에는 인공지능 분야에 대한 기술융합 맵 및 국가 프로파일에 대한 연구가 미진한 실정이다. 본 연구는 특허와 논문을 통해 인공지능 분야의 기술융합 현상을 밝히고, 인공지능 분야의 국가 프로파일을 분석하고자 하였다. 특허와 논문에서 인공지능 분야 데이터를 추출한 후 기술융합 맵을 작성하였다. KISTI가 보유한 SCOPUS 데이터를 이용해 국가 프로파일 분석에 필요한 지표를 구했다. 기술적 측면에서 인공지능 분야의 기술은 금융가격결정, 이미지분석, 수술 등 분야와 기술융합이 활발하게 나타났다. 학문적 측면에서 보면 인공지능 분야는 컴퓨터 과학 하위 분야에서 주로 연구되고 있지만 전기전자공학, 바이오 공학, 의학 등 분야와 융합이 활발하게 나타났다. 우리나라는 인공지능 분야에 대한 연구 성장도가 세계 평균인 것으로 나타났으며, 국가집중도, 영향력 등 측면에서는 주요국과 격차가 큰 것으로 나타났다.

• 융합보안논문지
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• 제18권5_1호
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• pp.75-81
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• 2018

근래에 산업이 융합됨에 따라, 산업 간 융합 도구 활용이 조직 내 보안성에 미치는 영향이 증가하고 있다. 그러나, 조직구성원들은 기존의 시스템을 중심으로 비즈니스를 활동하기 때문에 새로운 시스템 도임에 대한 적응력이 부족하고, 이에 따라서, 보안에 대한 고려는 후 순위로 나타날 수 밖에 없는 환경이다. 본 연구에서는 의료융합산업에서 중소형 의료기관을 대상으로 보안 체계를 구축하기 위해 우선적으로 고려해야 할 요소들에 대한 비용 효율적인 선택방안에 대하여 연구하였다. 구체적으로 선행연구들을 통하여 현재의 법제도 체계를 고려하고 보안현황을 분석하였을 때, 중소형 의료기관에서 필요한 보안 솔루션/시스템/체계에 대하여 도출하였다. 그리고, 실제 비즈니스 환경에서 중소형 의료기관 관련자들을 대상으로 비용 효율적으로 보안 체계를 구축하기 위한 상대적 우선순위에 대하여 분석하고 전반적인 보안체계를 구축하기 위한 방안을 제시하였다.

• 한국정보컨버전스학회논문지
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• 제5권2호
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• pp.25-35
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• 2012

현대 유통산업에서 기업들은 많은 전략을 구사하고 있다. 유통구조의 개선은 기업의 중대한 과제인 동시에 국가적으로도 그 비중이 너무나 크다. 국내 유통시장의 변화는 기업의 마케팅 정책 수립에 중대한 영향을 가져온다. 라이프스타일과 소비트렌드의 다양성도 유통환경에 많은 변화를 가져왔으며 그 대응전략도 다양하다. 따라서 본 연구는 급변하는 유통분야 발전에 기초 자료가 되고 향후 연구에 출발점이 되고자 한다.

• 전자공학회논문지D
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• 제34D권8호
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• pp.15-25
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• 1997

The integration method of carier concentrations to redcue the discretization error of th box integratio method used in the discretization of the three-dimensional poisson's equation is presented. The carrier concentration is approximated in the closed form as an exponential function of the linearly varying potential in the element. The presented method is implemented in the three-dimensional poisson's equation solver running under the windows 95. The accuracy and the convergence chaacteristics of the three-dimensional poisson's equation solver are compared with those of DAVINCI for the PN junction diode and the n-MOSFET under the thermal equilibrium and the DC reverse bias. The potential distributions of the simulatied devices from the three-dimensional poisson's equation solver, compared with those of DAVINCI, has a relative error within 2.8%. The average number of iterations needed to obtain the solution of the PN junction diode and the n-MOSFET using the presented method are 11.47 and 11.16 while the those of DAVINCI are 21.73 and 23.0 respectively.

• 한국산업융합학회 논문집
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• 제5권3호
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• pp.247-254
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• 2002

This study has researched the following conclusion to compare to the existing theory and to examine lateral earth pressure, which have measured to add incremental load on sandy soil, and were different in types of compaction by modeling earth pressure test. Lateral earth pressure by incremental load shows that it is increasing at depth forty four centimeters as 2/3H point for wall high, and under 2/3 H point the variation of earth pressure on incremental load is not conspicuous. Therefor, the more a position of surcharge load is close with fixed wall, the more a variation of lateral earth pressure marks considerably. According to relative compaction density of soil, lateral earth pressure turns up larger effective value for layer compaction test to a thickness of thirty three centimeters than layer compaction test to a thickness of twenty centimeters by the roller.