• 산업기술연구
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• 제31권A호
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• pp.109-112
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• 2011

In this paper, we proposed a planar reversed triangle monopole antenna for UWB(Ultra Wideband) communication. RF-60A substrate of 0.64 mm thickness and 6.15 relative permitivity and 0.035 mm conductor of thickness and loss tangent 0.0025 is used for implementation. We have used Ansoft $HFSS^{TM}$(High Frequency Structure Simulator) to simulate the proposed antenna. The proposed antenna showed return losses about -10 dB, nearly omni-directional radiation patterns and maximum gains are over -5 dBi at the frequency band from 3.1 GHz to 10.6 GHz for ultra wide band communication.

• Progress in Superconductivity
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• 제3권2호
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• pp.178-182
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• 2002

Superconducting four-element patch array antenna was designed and fabricated using $high-T_{c}$ superconducting (HTS) thin film. The array antenna has single-feed circularly polarization and a resonance frequency of 11.85 GHz fur satellite communication system. To fabricate this antenna $YBa_2$$Cu_3$$O_{7-x}$(YBCO) superconducting thin films were deposited using rf-magnetron sputtering technique. Sequential rotation technique based on radiation elements($0^{\circ}$ , $90^{\circ}$, 1$80^{\circ}$, $270^{\circ}$ phase delay) was utilized to achieve circularly polarization. Simulated and measured results, the analysis on resonant frequency(fr), return loss, and bandwidth are presented. The results show that 10 dB return loss bandwidth of the array antenna is 11.04 GHz~12.59 GHz (13.15%) and 3dB axial ratio bandwidth is 11.42~12.52 GHz (9.2%).).).

• 한국실내디자인학회논문집
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• 제22권1호
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• pp.256-264
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• 2013

A bathroom in house has been stressed not only as a space for physiology and hygiene but also leisure and healthcare. However, the bathroom is the most likely space where an elderly person can have an accident and it is uncomfortable space for them because of their deteriorating physical ability. So the purpose of this study is to help the elderly use their bathroom conveniently by providing smart service. Therefore, we carry out 18 smart service patterns that contain assistive devices and sensors for bathroom. Considering applicability and frequency, from among these service patterns, we suggest 4 service patterns. First is a fall prevention service. This service helps elderly use the bathroom safely at night. Second is a getting ready to go out service. This service helps the situation that elderly use the bathroom after getting up in the morning. Third is a security service in daily life especially before or after meals. And final is a service regarding personal hygiene service after returning home. This service helps to shower or bathe after return home. These services have positive influence in medical expense reductions, good health care and self-reliance of elderly.

• 가정과삶의질연구
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• 제23권3호
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• pp.153-167
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• 2005

This study was conducted to help develop women's human resources and promote married women's return to workforce. Using various data, we examined the patterns of Korean women's economic activities over the lifecycle, career discontinuation and return to the workforce. We also interviewed twenty full-time housewives who wanted to return to workforce. The interview questions included reasons for seeking employment, desired working conditions, and difficulties in finding a job. Major findings are as follows: First, there were two groups with respect to reasons why they want employment One was an economic need such as earning basic living expenses and supporting the family. The other was self-realization and social participation. Second most women wanted to do unskilled labor such as housekeeping work, whereas some young or well-educated women looked for a professional job. Third, married women preferred part-time jobs, which were compatible with their family care demands. Most of them wanted a workplace located close to home. The women with child-care responsibility preferred working at home. Fourth, regarding difficulties of returning to workforce, they pointed out vocational ability problems due to their career discontinuation, social prejudice such as gender discrimination and psychological pressure in maintaining work and family at the same time. In order to promote employment of married women, it is required not only to change social prejudices but also to increase effectiveness in policy implementation. In addition, counseling for job-search and vocational ability training programs should be provide.

• 한국전자통신학회논문지
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• 제10권5호
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• pp.549-556
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• 2015

본 논문에서는 인셋 급전 구조에서 마이크로스트립 패치 안테나 소형화를 위해 접지면에 CSLR 9개 적용한 안테나('CSLR 09' 안테나)와 8개 적용한 안테나('CSLR 08' 안테나)를 설계한 후, 유전율 2.5, 두께 0.787 mm인 기판으로 안테나를 제작하여 반사손실과 복사패턴에 대한 이론 결과와 실험 결과를 비교하였다. 'CSLR 09'와 'CSLR 08' 안테나의 이론 결과에서는 공진주파수 2.82 GHz에 반사손실이 각각 -25.35 dB와 -16.77 dB를 보였고, 측정결과에서는 공진주파수 2.885 GHz에 반사손실이 각각 -30.72 dB와 -14.90 dB를 나타내어 두 경우 모두에서 거의 일치하는 결과를 얻었다. 또한 E-면과 H-면 복사패턴에 대한 실험 결과에서도 이론 결과와 거의 일치하는 양호한 결과를 얻었다.

• 한국사회복지학
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• 제64권4호
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• pp.359-381
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• 2012

본 연구는 산재근로자의 첫 직업복귀기간의 추이를 살펴보고, 이에 영향을 미치는 요인을 분석하고자 하였다. 이를 위하여 2009년 요양종결한 산재근로자를 대상으로 설문조사를 실시하여 최종적으로 791명의 자료를 이용하였으며, 카플란-마이어 분석과 콕스 회귀분석을 활용하여 분석하였다. 카플란-마이어 분석결과, 재해이후 첫 직업복귀 추이를 보면 1개월 이내 복귀하는 경우가 2.65%, 6개월 이내 28.82%, 12개월 이내 50.95%, 24개월 이내 71.69%로 나타났으며, 요양종결 이후 첫 직업복귀 추이를 보면 요양중 혹은 종결 직후 복귀하는 경우가 29.46%, 1개월 이내 36.41%, 6개월 이내 56.64%, 12개월 이내 67.54%로 나타났다. 그리고 재해이후 첫 직업복귀기간은 여성보다는 남성이, 연령이 낮을수록, 임금이 높을수록, 요양중 실직하지 않은 경우, 원직복귀한 경우, 허리질환에 비하여 골절이, 수술하지 않은 경우, 요양기간이 짧을수록, 장해가 경할수록, 직업훈련을 받은 경우가 첫 복귀가 빨랐다. 요양종결이후 첫 직업복귀기간은 여성보다는 남성이, 연령이 낮을수록, 원직복귀한 경우, 장해가 경할수록, 직업훈련을 받은 경우가 첫 복귀가 빨랐다. 이러한 연구결과를 바탕으로 하여 연구의 함의 및 정책적 개입 방안들을 제시하였다.

• Asia pacific journal of information systems
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• 제27권4호
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• pp.233-244
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• 2017

IT portfolio, meaning the ratio of investment with four different purposes of IT, is widely used for evaluating the adequacy of investment and its performance within firms. Despite of such a useful framework looking at investment on IT, IT portfolio in agriculture industry seems to be differentiated from other industries. In this study, we compared IT portfolios of farms: grain, field fruit and vegetable, greenhouse fruit, greenhouse vegetable, beef cattle and pig. We classified farms by their return on equity (ROE) in order to analyze the relationship between IT portfolio of each crop and performance. Then, we found patterns of IT portfolios of top-performance farms compared to all farms for each agricultural product. Lastly, peculiarities of each crop are interpreted and discussed to find out top-performance farms' IT investment patterns. From our study, it could be inferred that monotonous IT investments may not be as effective.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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• pp.372-375
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• 2003

The incidence of blindness resulting from diabetic retinopathy has significantly increased despite the intervention of insulin to control diabetes mellitus. Early signs are microaneurysms, exudates, intraretinal hemorrhages, cotton wool patches, microvascular abnormalities, and venous beading. Advanced stages include neovascularization, fibrous formations, preretinal and vitreous microhemorrhages, and retinal detachment. Microaneurysm count is important because it is an indicator of retinopathy progression. The purpose of this paper is to apply data mining to detect diabetic retinopathy patterns in routine fundus fluorescein angiography. Early symptoms are of principal interest and therefore the emphasis is on detecting microaneurysms rather than vessel tortuosity. The analysis does not involve image-recognition algorithms. Instead, mathematical filtering isolates microaneurysms, microhemorrhages, and exudates as objects of disconnected sets. A neural network is trained on their distribution to return fractal dimension. Hausdorff and box counting dimensions grade progression of the disease. The field is acquired on fluorescein angiography with resolution superior to color ophthalmoscopy, or on patterns produced by physical or mathematical simulations that model viscous fingering of water with additives percolated through porous media. A mathematical filter and neural network perform the screening process thereby eliminating the time consuming operation of determining fractal set dimension in every case.

• Journal of electromagnetic engineering and science
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• 제5권3호
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• pp.105-111
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• 2005

This paper presents the basic characteristics of a cutoff cavity-backed aperture antenna with a feed post and a parasitic post inserted parallel to the aperture. It is shown that this type of antenna forcibly resonates the cutoff cavity by adding a single external reactance to the parasitic post. The Galerkin's method of moments is used to analyze integral equations for the unknown electric current on each post and the aperture electric field on the aperture. The value of an external reactance for forced resonance is analytically obtained by deriving a determining equation. Also the current distribution on each post, aperture electric field distributions, and the radiation patterns are discussed. The theoretical analysis is verified by the measured return loss and radiation patterns.

• 물과 미래
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• 제29권3호
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• pp.207-216
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• 1996

본 연구에서는 기존의 주택지외곽의 하천 하류부 저지대를 대규모로 개발하여 택지를 조성하는 사업이 진행되고 있는 인천시 부평구 관내의 동수천유역을 대상으로 장차 하류부 전체에 대해 택지개발이 계획되고 있는 점을 고려하여, 이 유역의 개발로 인한 총유출량과 첨두유량 및 첨두도달시간의 변화정도를 도시화단계별, 재현기간별, 강우분포형태별로 살펴보았다. ILLUDAS 모형을 사용하여 유출해석을 하고 도시화단계를 3가지 단계로 나누고 7가지 재현기간에 따라 설계강유량을 Huff의 4분위법으로 분포시켜 유출해석한 결과, 강우분포형별 첨두유량의 크기는 Huff 4 분포, Huff 2 분포, Huff 3 분포, Huff 1 분포형순으로 나타났다. 강우분포형별로 도시화단계 70%를 기준으로 80, 90%에 따른 총유출량의 평균증가율은 3.5, 5.5% 였고, 첨두유량의 평균증가율은 4. 2%, 8.8%로 나타났으며, 첨두도달시간의 감소율은 4.4, 10.1%로 나타났다. 또한 각 재현기간별로는 도시화단계 80, 90%에 의한 총유출량의 평균증가율은 3.0, 5.4%였고, 첨두유량의 평균증가율은 3.9%, 8.0%로 나타났다.