• 한국멀티미디어학회논문지
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• 제11권8호
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• pp.1082-1092
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• 2008

무선 센서 네트워크에서 LEACH와 같은 클러스터링 프로토콜은 전체 네트워크의 수명을 연장시키는 효율적인 방법이지만 클러스터 헤드 노드에 높은 부하를 주게 되어 급격한 에너지 소모를 유발하는 문제가 있다. 따라서 클러스터의 구성과 클러스터 헤드 노드의 역할을 주기적으로 교체하여 네트워크의 수명을 연장시켰다. 그러나 이 방법은 클러스터를 구성하는 과정에서 상당한 량의 에너지 소모를 보인다. 따라서 본 논문은 소모되는 에너지의 효율성 증대를 위해 클러스터링 알고리즘을 제안하였다. 이 알고리즘에서 서로 인접한 노드들은 intra cluster를 이루며 이 클러스터를 구성하는 노드들은 라운드 로빈 형태로 데이터를 수집하고 전송한다. 전체 네트워크의 관점에서 볼 때 이 intra cluster는 한개의 노드로 취급된다. 한 라운드의 setup단계에서 intra cluster들은 클러스터 헤드(intra cluster)에 의해 다시 클러스터를 형성(network cluster)하게 된다. 클러스터 헤드가 된 intra cluster의 모든 멤버노드는 라운드 로빈 방식으로 클러스터 헤드 역할을 수행한다. 따라서 intra cluster의 크기에 의해 라운드의 주기를 연장할 수 있다. 또한 steady-state에서 각 intra cluster의 노드는 라운드 로빈 방식으로 데이터를 수집하며 network cluster의 클러스터 헤드에 전송한다. 성능분석 결과 제안하는 방법은 제안된 클러스터링 방법에 비해 노드들의 에너지 소모가 줄어들었으며 전송 효율이 증가하였다.

• Journal of Nutrition and Health
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• 제33권2호
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• pp.193-201
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• 2000

This study was conducted to investigate the effectiveness of nutrition counseling on the dietary intake and nutritional status cancer patients undergoing radiotherapy treatment. The study was conducted over 6 week period and included 104 patients : 66 received nutrition counseling as the variable group of 42 male and 24 female and 38 patients received no counseling as the control group of 19 male and 19 female. Nutrition counseling was accompanied with the radiation therapy and adminstered via counseling session and distribution of printed material during radiation therapy for 6 weeks. Nutrition counseling aimed at maintaining a balanced diet and preventing weight loss of subjects, guideline used for energy and protein intake were 35kcal/kg IBW and 1.5-2.0g/kg IBW, respectively. Over the course of the study, the counseling group increased significantly in comparison to the control group's energy intake, evidenced by the counseling group's initial mean daily energy intake of 1932.0kcal, and 4 and 6 week mean energy intake values of 2046.6kcal, 2066kcal, respectively. But mean energy values of control group was 1614.3kcal at 4 week. Th energy intake per weight values and protein intake per weight values for initial, 4 and 6 week intervals for counseling group were 33.2kcal/kg, 33.7kcal/kg, 34.0kcal/kg, and 1.48g/kg, 1.58g/kg, 1.59g/kg, respectively. Based on results, nutrition counseling had positive effects on both the variety of diet and energy intake of the variable group, mostly due to an increase in dairy product and egg consumption. In addition, the percentage of counseling group patients who consumed all 5 food group increased from 48.5% to 54.5%. Sufficient energy intake and protein consumption seem to be important factors in weight loss prevention, evidenced by weight gain by subjects in the counseling group who had 36.1kcal/kg/day mean energy intake and 1.77g/kg/day mean protein intake after 4 weeks. Counseling group subjects experiencing weight loss had lower intake and 1.77g/kg/day mean protein intake after 3 weeks. Counseling group subjects experiencing weight loss had lower intakes of 29.3kcal/kg/day for energy and 1.33g/kg/day for protein during the same period. Another significant factor in weight loss prevention of the counseling group could be the variety of diet. The dietary variety scores(DVS) of both counseling and control groups differed significantly : the counseling group had a mean score of 34 while the control group of patients. At the end of the study, the mean percentage of subjects within each group having a DDS 5 was higher in the counseling group (54.5% v.s. 24.0%). In this study, nutrition counseling for cancer patients undergoing radiation therapy proved to be effective in preventing weight loss, a major complication during radiotherapy. Nutrition counseling not only increased protein and energy intake, but also had desirable effects on variety or diversity of diet.

• KIEAE Journal
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• 제15권3호
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• pp.49-56
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• 2015

Purpose: Due to recent increase on energy consumption for light in building, many studies to mitigate this issue have been conducted. Various researches have been carried out to suggest light shelf as one of the solutions, but researches for its reflectivity is very few. In fact, existing research on light shelf shows that utilizing more than 90% of high-illumination materials causes imbalance of glare and illuminance. Method: Therefore this research aimed to evaluate the performance of light shelves depending on reflectivity and to identify proper solution through test-bed. Result: The results are following: 1) Increased reflectivity generally contributed to increase of indoor illuminance but degrade uniformity factor related with indoor comfort of light environment. 2) The $0^{\circ}fixed$ light shelf with 75% of reflectivity and width of 300mm and 40mm appeared to consume more energy than other shelves. Therefore, it is analyzed as unsuitable. 3) This research was conducted by calculating appropriate angle of light shelf around winter and summer solstices and vernal/autumnal equinox. Based on this, performance evaluation was undertaken depending on reflectivity of movable light shelf, which is activated by external sources and can be applied with lower reflectivity than fixed shelf. However, one exception was a movable shelf with width of 600mm that increased light energy consumption when 75% of reflectivity was applied. 4) Performance evaluation of fixed and movable light shelf showed that the shelf with 80% of reflectivity came up with suitable results, but 75% of reflectivity may be applied depending on the width and angle of the shelf. This research is meaningful in that estimation of appropriate reflectivity of light shelf can resolve the glare problem and improve light environment, and further research would be desirable under more diverse conditions to identify proper solution.

• 한국환경과학회지
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• 제25권3호
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• pp.439-446
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• 2016

Domestic sewerage treatment plant is operated by activated sludge method and its modified method by using microorganism. In most cases, a method of using microorganism is directly controlled by the operator based on individual judgment through factors of DO, pH and ORP. In addition, under aerobic condition in bioreactor, energy consumption including excessive air injection is learned to be somewhat plenty. In order to solve this problem, in most of the process, improvement of internal recycling and activated environmental factor of microorganism were researched extensively. However, as factors are changed depending on various conditions, it is not sufficient as an indicator of judgment. As such, a research on operation of bioreactor that measures metabolic change in short time by directly measuring activated condition of microorganism using NADH fluorometer is required in reality.It is considered that the method like this could supplement problem of energy consumption being occurred in the existing treatment method and operational optimization of bioreactor would be enabled by controlling optimal air volume. Therefore, in this study, in order to obtain optimal operational indicator of bioreactor, proper air volume control test was performed and through batch test and site evaluation, possibility of NADH sensor being utilized as operational control indicator of bioreactor is intended to be analyzed. In order to compare with measured value, DO, ORP that are operational control indicator of existing bioreactor were used. As MLSS concentration was increased through batch test, NADH value was increased and site evaluation also showed similar tendency to batch test. Resultantly, it could be confirmed that changing level of NADH fluorometer was a sensor that could measure bioreactor condition effectively and optimized scale of bioreactor is considered to be utilized.

• Journal of Radiation Protection and Research
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• 제23권4호
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• pp.243-249
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• 1998

원자력 사고 후 우유에 대한 비상대응방법론을 비용/편익 분석법에 근거하여 고안하였다. 목초의 왕성한 성장시기인 8월 15일을 방사성물질의 침적시점(사고시점)으로 가정하여 지표위 방사성물질의 농도, 침적 후 대응행위의 시작시점과 수행기간의 함수로써 적용결과를 논의하였다. 침적 후 우유내 방사성물질의 농도는 동적섭식경로모델 DYNACON으로부터 예측되었다 대응행위로는 침적 후 첫해에 피폭을 효과적으로 줄일 수 있고 수행하기 용이한 섭취금지와 비오염 사료대체가 고려되었다. 대응행위 수행에 따른 총비용은 피폭부담과 금전비용의 합으로 평가하였다. 침적 후 신속한 대응은 소요되는 금전비용에 대한 피폭저감 측면에서 중요한 변수였다. 많은 경우 비오염 사료대체는 섭취금지보다 비용측면에서 효과적인 대응행위였다. 대응행위를 빨리 취할수록 대응행위의 정당화 및 최적기간은 증가하였다.

• 한국기후변화학회지
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• 제1권3호
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• pp.211-217
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• 2010

건설 장비, 항공 지상 지원 장비, 항만 하역 장비, 농림업 기계를 포함하는 비도로 수송 부문의 경우 IPCC Guidelines의 배출원 분류 코드에 비도로 수송(1A3e2)이 존재하나, 국내에서는 배출자료가 구축되지 못하고 있다. 본 연구에서는 건설업, 항공, 해운, 농림업에 해당하는 석유 통계 자료를 유종별로 구분하였고, 1996 및 2006 IPCC Guidelines에서 제시하는 배출 계수로 Tier 1 수준의 비도로 수송 부문 온실 가스 배출량을 산출하고 비교하였다. 그 결과, 1996 IPCC Guidelines과 2006 IPCC Guidelines에 의한 2007년 비도로 수송 온실 가스 배출량은 각각 4,919천ton $CO_2eq./yr$, 5,530천ton $CO_2eq./yr$으로 나타났다. 본 연구에서 추정한 비도로 수송 온실 가스 배출량은 국내 수송 부문 온실 가스 배출량의 약 5.5%에 해당하는 양으로 추정되었다.

• 유기물자원화
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• 제21권4호
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• pp.50-61
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• 2013

교내 식당에서 분리 수거된 음식물류 폐기물에서 재생 에너지인 메탄가스를 생산하기 위해 혐기성 소화시스템에 대한 연구가 수행되었다. 1차 실험에서 침출수 인발/반송도 없고 혼합도 없는, 침출수 인발/반송은 없고 혼합이 있는, 침출수 인발/반송은 있고 혼합이 없는, 그리고 침출수 인발/반송은 있고 혼합이 있는 4개의 혐기성 시스템에서 침출수 인발/반송은 있고 혼합이 없는 시스템에서 가스발생이 가장 많은 것으로 나타났다. 반응조 혼합이 없고 침출수 인발/반송이 수행되는 시스템에서는 침출수의 반응조 내 침출수 유출속도가 빠른 경우에 혐기성 반응이 활발히 일어난 것으로 관찰되었다. 가스수집기 무게가 1kg이고 음식물류 폐기물 C/N비가 10이상이 되는 경우 혐기성 반응조의 가스가 소모되어 가스수집기에 부압이 걸리는 것이 관찰되었는데, 이에 대한 원인을 밝히는 것이 음식물류 폐기물에서 재생에너지를 회수하는데 필수적이다.

• 청정기술
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• 제23권2호
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• pp.181-187
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• 2017

반도체 및 디스플레이 산업에서 배출되는 과불화합물은 연소, 열, 플라즈마, 촉매 등의 다양한 방법이 적용된 스크러버에 의해 분해 과정을 거친 후 배출되나, 운영 스크러버의 대부분이 과도한 에너지의 사용, 낮은 저감 효율을 보임으로써 이러한 단점의 극복이 요구된다. 압력순환흡착법과 다공성 매체 연소법의 두 가지 기술이 연계된 새로운 형태의 과불화합물 저감 스크러버를 개발하고 특성을 알아보았다. 분해 대상인 $CF_4$의 흡착비와 손실계수는 흡착 컬럼의 입구와 출구에서 농도 측정을 통해 계산하였으며, 연소기의 입구와 출구의 유량과 농도 측정을 통해 처리 효율을 계산하였다. 기존 스크러버와의 에너지 사용량 및 처리효율 비교를 위하여 다양한 유량에 대한 성능 평가가 진행되었다. 1412 ppm, 204 LPM의 $CF_4$가 유입된 흡착 컬럼에서의 흡착비는 1.65였으며, 유입되는 $CF_4$의 손실 계수는 8.2%였다. 이때 연소기로 유입되는 $CF_4$의 유량과 농도는 각각 91 LPM과 2335 ppm이었으며, $CF_4$ 19 LPM, $O_2$ 40 LPM을 사용한 연소 반응시 약 96%의 저감 효율을 나타내었다. 상용 스크러버와의 동일 운전 조건에서의 다공성 매체 연소에서의 $CF_4$ 저감 효율과 전체 에너지 사용 효율 비교시 각각 16%, 41% 이상의 저감 효율 상승과 에너지 절감 효과를 보였다.

• 천문학회보
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• 제41권1호
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• pp.79.3-80
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• 2016

We have investigated the correlation analysis between global temperature anomaly and two main factors: geomagnetic activity (aa index) of Earth external factor and CO2 of Earth internal factor. For this, we used NOAA Global Surface Temperature anomaly (Ta) data from 1868 to 2015. The aa index indicates the geomagnetic activity measured at two anti-podal subauroral stations (Canberra Australia and Hartland England) and the CO2 data come from historical ice core records and NOAA/ESRL data. From the comparison between (Ta) and aa index, we found several interesting things, First, the linear correlation coefficient between two parameters increases until 1985 and then decreases rapidly. Second, the scattered plot between two parameters shows a boundary of the correlation tendency (positive and negative correlation) near 1985. A partial correlation of (Ta) and two main factors (aa index, CO2) also shows that the geomagnetic effect (aa index) is dominant until about 1985 and the CO2 effect becomes much more important after then. These results indicate that the CO2 effect become very an important factor since at least 1985. For a further analysis, we simply assume that Ta = Ta(aa)+Ta(CO2) and made a linear regression between (Ta) and aa index from 1868 to 2015. A linear model is then made from the linear regression between energy consumption (a proxy of CO2 effect) and Ta-Ta(aa) since 1985. Our results will be discussed in view of the prediction of global warming.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제17권1호
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• pp.33-40
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• 2011

Daylight is highly beneficial for improving the indoor environmental quality and reducing building energy consumption, daylighting applications are scarcely considered, especially during the care facility design process, because of lack of previous studies on elderly- light environment and complex simulation process. Therefore, daylighting process were performed using ECOTECT, which has various advantage such as easy user interface and simple simulation processes. Moreover, dynamic daylight simulation were performed using whether data. Static simulation are performed to compute static metrics such as daylight factor, whereas dynamic simulation are performed for dynamic metrics such as daylight autonomy and useful daylight illuminance using annual weather data On the basis of daylight autonomy and useful daylight illuminance analysis result, variations in annual daylight performances. A parametric and regression analysis of the window-to-wall ratio and visible transmittance showed that daylight factor, daylight autonomy increased with window-to-wall ratio and visible transmittance. It can be concluded that this new daylight criteria. useful daylight illuminance, will enable architect to obtain better fenestration design.