• 산업기술연구
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• 제21권B호
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• pp.233-240
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• 2001

This research was conducted with the aim of efficiently managing large scale of rivers such like Songyang-river through predicting water quality change with analyzing the characteristics of the flowing in nutrients and pollutants. The main result will be used as basic data for effectively operating reservoirs through controling water quality and quantity. The relationship between quantity of flow and water quality was analyzed and pollution loading into the basin was estimated. Three areas of Soyang-river upstream and one area of Suip-cheon in Yanggu-gun were selected as research sites. Flow and water quality were measured simultaneously. The relation between quantity of discharge and pollution concentration and between quantity of discharge and pollution loading were analyzed by statistical method, respectively. We provided a rating curve through measuring quantity of discharge(collecting quantity of discharge) and pollutograph and pollution loading curve through water quality data. Also, we analyzed the correlation between quantity of discharge per unit area and pollution loading per unit area in each basin. As resurt of this research, Buk-cheon spot revealed an excellent first grade water quality for the items including $BOD_5$, DO, and SS. The correlation coefficient between Buk-cheon spot's quantity of discharge and pollution loading was 0.896~0.996, showing the validity of analysis applying correlation curve formula of quantity of discharge and pollution loading in the same spot. Also, pollution loading per unit area of the items including $BOD_5$, COD, DO, SS, T-N, T-P increased as the area of basins get increased following the sequence of Buk-cheon, Suip-cheon, Naelin-cheon spots.

• 한국입자에어로졸학회지
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• 제9권3호
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• pp.139-147
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• 2013

The performances of indoor air cleaners including particle cleaning capacity and collection efficiency are usually tested at the condition of the maximum air flow rate of the air cleaners. However, the power consumption of the air cleaners is highly dependent on the air flow rate of the individual air cleaners. Therefore, there seems to be an optimized air flow rate for the air cleaning capacity considering power consumption. In this study, clean air delivery rate(or standard useful area as suggested room size) and power consumption have been investigated for different maximum air flow rates of 15 air cleaners and then compared those for different air flow rate modes of the individual 5 air cleaners selected from the 15 cleaners. For the maximum air flow rate conditions of 15 air cleansers, the power consumption per unit area was less related to the maximum air flow rate. However, for the different air flow rate modes of the selected 5 air cleaners, the lower power consumption per unit area was corresponding to the lower air flow rate mode of the individual air cleaners. When considering the operation time to the desired particle concentrations, there was an optimized one in the medium air flow rate modes for the individual air cleaners. Therefore, not only the maximum air flow rate but also lower air flow rates of individual air cleaners should be considered for estimating air cleaning capacity based on energy consumption per unit area.

• 보건행정학회지
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• 제8권1호
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• pp.155-182
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• 1998

There exists a remarkable differences in use of MRI scanning among income classes. The poor can hardly utilize it. This is because, among high cost technnologies, MRI is the only equipment not covered under health insurance benefits in Korea. This study was designed 1) to reveal the status of nation-wide MRI installation, customary charges and per unit annual scanning performance, and 2) to analyse factors influencing the above variables. The data for this study came from "MRI Prevalence Survey" conducted by the National Federation of Medcial Insurance(NFMI) in 1997, and were analyzed through SAS packages for T-test, analysis of variance and stepwise multiple regression. Data were collected from 188 hospitals equipped with MRI scanners. Major findings are summarized as follows : The number of MRI scanners has increased from 69 in 994 to 158 in 1996(2.3 times) while per unit annual scanning performance has risen by 11.2% from 2,173 cases in 1994 to 2,417 cases in 1996. Such a rapid increase was made possible mainly due to the inclusion of CT scanning under the health insurance benefit package. The customary charges for MRI scanning with or without contrast media, on average, amounted to 484,000 Won and 402,000 Won, respectively, with the percentile increase of 17.8% and 8.1% each during the same time. Korea ranks the third worldwidely in terms of number of MRI installations, 4.8 scanners per one million persons, only next to Japan and United States. Geographical variation of MRI, however, was rather high, 7.91 unit, in Cheju area compared to 1.82 in Kyongnam area. Variations of customary charges of MRI scanning can be explained as much as by 44.8% by both the total amount of claims to NFMI and geographical variable. The charges were more likely to be higher in metropolitan areas like Seoul and in hospitals with a bigger amount of claims. While those of per unit annual scanning performance can be explained as much as by 30.7% by both MRI installation cost and level of MRI-installed organizations. Per capital scannig performance was higher in tertiary hospitals and hospitals equipped with more expensive scanners than hospitals with less expensive scanners. Two measures are called for the remedying the existing excessive abundance in MRI units in korea : One is to set a ceiling of MRI units in an area like a province or a metropolitan district. The other is to establish a committee on introduction of high cost technologies for reviewing its effective use.ctive use.

• 대한한의학회지
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• 제22권3호
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• pp.74-80
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• 2001

Objectives : Ma-huang is a traditional Chinese medicinal herb, derived from Ephedra sinica Stapf and other Ephedra species, used to treat asthma, nose and lung congestion, and fever with anhidrosis. It contains 0.5-2.5% by weight of total alkaloids, of which ephedrine accounts for 30 to 90%. Recently, Ma-huang has been used as a source of ephedrine in many dietary supplements formulated for the treatment of obesity, since ephedrine has been found to be effective in inducing weight loss in the obese. In this study the effects of the methanol extract of Ma-huang on the adipocyte of epididymal and brown fat pads in rats fed a high fat diet for six weeks were studied. Methods : Male Sprague Dawley rats weighing an average 94g (4 weeks old) were fed either a regular diet (RE) or a high fat diet (HF), and the HF group was subdivided into a Ma-huang methanol extract (30mg/100g body weight) group (HF+MH). The weight of epididymal fat pad and brown adipose tissue were measured. The cell size and cell number per unit area of epididymal fat pad were investigated. Results : The yield weight of methanol extract of Ma-huang was 3.63mg per l00g of Ma-huang. The body weight gain of the HF group was similar with that of the HF+ MH but higher than that of the RE. The weights of the epididymal fat pads and brown adipose tissue of the RE group were lower than those of HF and HF+MH groups. The cell sizes and numbers per unit area of epididymal fat pads of the RE and HF+MH groups were larger than those of HF group. The cell numbers per unit area size of epididymal fat pads were the smallest in the RE group. Conclusions : It could be concluded that the Ma-huang extract has no effect on the epididymal fat pads in rats fed a high fat diet and the clinical application of Ma-huang for the treatment of obesity should be re-considered.

• 한국산림과학회지
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• 제59권1호
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• pp.15-30
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• 1983

제일대(第一代) 잡종(雜種) 포플러 Poulus alba${\times}$Populus glandulosa $F_1$의 우량(優良) clone을 선발(選拔)하기 위해, 서울대학교(大學校) 농과대학(農科大學) 묘포장(苗圃場)에서 밀식재배(密植栽培)(20.000본(本)/ha)한 1,2년생(年生) 각각(各各) 13,15 clones을 대상(對象)으로 생장(生長)과 생장(生長)에 관련(關聯)된 몇 생리적(生理的) 특성(特性)을 조사(調査), 비교(比較)하였다. 개체당(個體當) 건중량(乾重量), 엽면적(葉面積), 단위엽면적당(單位葉面積當) 엽록소(葉綠素) 함량(含量)에 있어서 2년생(年生) clone들 간(間)에는 고도(高度)의 유의차(有意差)가 인정(認定)되었으나, 1년생(年生) clone들에 있어서는 유의차(有意差)가 인정(認定)되지 않았다. 개체당(個體當) 건중량(乾重量)과 개체당(個體當) 엽면적(葉面積)과의 상관관계(相關關係)는 r=0.865, 개체당(個體當) 건중량(乾重量)과 개체당(個體當) 엽록소함량(葉綠素含量)과의 상관관계(相關關係)는 r=0.888로 고도(高度)의 상관(相關)이 인정(認定)되었으며, 개체당(個體當) 건중량(乾重量)과 개체당(個體當) 광합성능력(光合成能力)과의 상관관계(相關關係)에서는 r=0.745로 비교적(比較的) 높은 상관(相關)이 인정(認定)되었다. 1년생(年生) clone의 엽부위별(葉部位別) 엽단위면적당(葉單位面積當) 광합성능력(光合成能力)과 엽록소함량(葉綠素含量)은 엽순서(葉順序)가 증가(增加)함에 따라 증가(增加)하여 28번째와 33번째 엽(葉)에서 각각(各各) 최대치(最大値)를 보였으며 그후 아래엽(葉)으로 내려올수록 감소(減少)하는 경향(傾向)을 보였다. Clone 68-1-54, 66-26-55, 65-22-11 등(等)은 개체당(個體當) 엽면적(葉面積), 단위면적당(單位面積當) 엽록소함량(葉綠素含量) 및 광합성능력(光合成能力)으로 보아 다른 clone들 보다 양호(良好)한 생장능력(生長能力)을 보였다. 제일대잡종(第一代雜種) 포플러, Populus alba${\times}$Populus glandulosa $F_1$ 유시(幼時) 생장량(生長量)은 개체당(個體當) 엽면적(葉面積)이나 개체당(個體當) 엽록소함량(葉綠素含量)으로 추정(推定)할 수 있었으며, 이러한 사실(事實)로 보아, 엽면적(葉面積)과 엽록소함량(葉綠素含量)의 측정치(測定値)는 본(本) 잡종(雜種) 포플러의 우량(優良) clone을 선발(選拔)하는 하나의 기준(基準)으로 사용(使用)될 수 있다.

• 한국정보과학회논문지:시스템및이론
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• 제31권8호
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• pp.453-464
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• 2004

In order to solve the well-known drawback of reduced flexibility that is associate with ASIC implementations, this paper proposes a novel arithmetic unit over GF(2$^{m}$ ) for field programmable gate arrays (FPGAs) implementations of elliptic curve cryptographic processor. The proposed arithmetic unit is based on the binary extended GCD algorithm and the MSB-first multiplication scheme, and designed as systolic architecture to remove global signals broadcasting. The proposed architecture can perform both division and multiplication in GF(2$^{m}$ ). In other word, when input data come in continuously, it produces division results at a rate of one per m clock cycles after an initial delay of 5m-2 in division mode and multiplication results at a rate of one per m clock cycles after an initial delay of 3m in multiplication mode respectively. Analysis shows that while previously proposed dividers have area complexity of Ο(m$^2$) or Ο(mㆍ(log$_2$$^{m}$ )), the Proposed architecture has area complexity of Ο(m), In addition, the proposed architecture has significantly less computational delay time compared with the divider which has area complexity of Ο(mㆍ(log$_2$$^{m}$ )). FPGA implementation results of the proposed arithmetic unit, in which Altera's EP2A70F1508C-7 was used as the target device, show that it ran at maximum 121MHz and utilized 52% of the chip area in GF(2$^{571}$ ). Therefore, when elliptic curve cryptographic processor is implemented on FPGAs, the proposed arithmetic unit is well suited for both division and multiplication circuit.

• 한국습지학회지
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• 제2권1호
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• pp.87-94
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• 2000

The purpose of this study was to analysis the pollutant loading of Chin yang Reservoir according to the variation of outflow. Regression equation of the pollutant loading and outflow was represented as $L=a\;Q^b$ in which L = pollutant loading(kg/day), a and b = regression coefficient, and Q = outflow($m^3/day$). Regression coefficients ($R^2$) of Sanchung, Sinan and Changchon site was in range of 0.8376 to 0.9818. Therefore the pollutant loading was good correlated with outflow. Changchon site had minimum b value because outflow of pollutant was little compared with rainfall. The SS was the highest b value 1.621~1.7834 among water quality parameters because the pollutant loading of SS was much affected by outflow. Also, the pollutant loadings per area could be calculated and compared in case of the dry season, normal season and flood season. The pollutant loading in the normal and flood season except the dry season were higher in order of Sanchung, Sinan and Changchon site. Pollutant loading per area were higher in order of Sinan, Sanchung and Changchon site. When it compared with pollutant loading per area calculated using pollutant unit loading, T-N was much different each other.

• 한국포장학회지
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• 제6권1호
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• pp.1-11
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• 2000

In optimum design of packaging container for bulk materials, minimum board area, compression performance and distribution efficiency must be considered. In this study, mathematical models for minimum board area (RMA), compression strength (CS) and maximum compression strength per unit board area (MCSA) of container as algorithm for optimum design of packaging conatiner for bulk materials were developed as follows : RMA=f(V,D), ${\alpha}_{RMA}=f(V,D)$, MCSA=f(V,D), and ${\alpha}_{MCSA}=f(V,D)$. In order to develop these models, compression test according to various dimensions of container and response surface analysis for minimum board area, compression strength, and maximum compression strength per unit board area of container were carried out. In developed models, volume and depth of container were principal independent variables. Through the verified results for these models, optimum design of packaging container on the design conditions and limit conditions was possible. These models might be used in developing optimum design software of packaging container for bulk materials.

• 한국자원식물학회지
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• 제16권2호
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• pp.118-122
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• 2003

흑색 비닐피복과 재식밀도에 따른 지황의 생육과 수량에 미치는 영향을 구명하기 위해 지황 1호를 시험재료로 흑색 비닐피복과 재식밀도를 달리하여 재배 시험을 수행하였던 결과를 요약하면 다음과 같다. 출현율은 무피복 78.0%에 비하여 흑색 비닐피복에서 3.1%더 높았고, 재식밀도 간에는 차이가 없었다 생육은 흑색 비닐피복과 소식에서 생육이 왕성하였으나, 단위 면적 당 엽 중, 근경 수는 밀식 할수록 무겁거나 많았다. 건근경중은 무피복 402 kg/10a에 비하여 흑색 비닐피복재배에서 28% 증수되었으며, 개체 당 건근경중은 소식할수록, 단위면적 당 수량은 밀식 할수록 증가하였다.

• KIEAE Journal
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• 제14권5호
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• pp.103-109
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• 2014

Apartment housing should require the systematic maintenance to provide the decent living condition during its life. Each household should participate the maintenance activities and pay for the repair. Therefore, the required cost for repair would be needed to plan in the repair schedule because each household could not pay the much repair money at a time. After apartment constructed, a long term repair plan would be prepared in repair time, repair scope and a required cost. A few studies are said that the repair cost depends on the building deterioration, elapsed year and management factors. The above factors are not be certain to affect the repair management while it may be important to prepare the required money and the repair time. In this paper, it aimed at analyzing the correlation between the repair management and the management factors, especially total area, number of household. This would educe the unit cost per number of household and management area in the individual boiler and elevator with full change and full repair. The unit cost per number of household and area for full change are about 199,000 won/household and $1,954won/m^2$ in the individual boiler respectively. The unit cost of the elevator for full change is 94,000 won/household and $5,429won/m^2$ respectively. Second, this study shows that the elapsed year after construction would not be related the repair unit cost.