• 한국가스학회지
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• 제23권5호
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• pp.52-58
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• 2019

본 연구에서는 국내 도시가스 인수량에 대한 예측 모델을 개발하였다. 국내의 도시가스 회사는 KOGAS에 차년도 수요를 예측하여 보고해야 하므로 도시가스 인수량 예측은 도시가스 회사에 중요한 사안이다. 도시가스 사용량에 영향을 미치는 요인은 용도구분에 따라 다소 상이하나, 인수량 데이터는 용도별 구분이 어렵기 때문에 특정 용도에 관계없이 영향을 주는 요인으로 외기온도를 고려하여 모델개발을 실시하였다.실험 및 검증은 JB주식회사의 2008년부터 2018년까지 총 11년 치 도시가스 인수량 데이터를 사용하였으며, 전통적인 시계열 분석 중 하나인 ARIMA(Auto-Regressive Integrated Moving Average)와 딥러닝 기법인 LSTM(Long Short-Term Memory)을 이용하여 각각 예측 모델을 구축하고 두 방법의 단점을 최소화하기 위하여 다양한 앙상블(Ensemble) 기법을 사용하였다. 본 연구에서 제안한 일별 예측의 오차율 절댓값 평균은 Ensemble LSTM 기준 0.48%, 월별 예측의 오차율 절댓값 평균은 2.46%, 1년 예측의 오차율 절댓값 평균은 5.24%임을 확인하였다.

• 융합신호처리학회논문지
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• 제9권4호
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• pp.245-252
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• 2008

본 논문에서는 H 264 인코딩 과정 중 모드 결정 및 움직임 예측 부분의 개선을 위한 새로운 방법을 제안한다. 제안한 방법은 H 264 모드 결정 과정 중 참조 프레임의 선택 과정 생략과 모드 결정 기준의 하나인 SAD 연산과정의 개선을 사용하여 인코딩 과정에서 수행되는 연산량을 감소시켜 인코딩 수행시간을 절감하는 방법이다. 제안하는 방법의 성능 평가를 위하여 H 264 표준에서 제공되는 QCIF 사이즈, YUV 4:2:0 포맷의 영상을 이용하여 실험 영상을 만들어 적용하였다. 본 논문에서 제안한 방법을 적용한 결과 알고리즘 1은 약간의 화질 열화를 보이며 수행시간은 10프레임씩 인코딩 하였을 때 평균 4.7% 감소하였으며, 알고리즘 2는 약 0.98dB정도의 화질 열화를 보이지만 인코딩 수행시간은 평균 9.6% 감소하였다.

• 한국병원경영학회지
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• 제11권2호
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• pp.61-86
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• 2006

Based on a previous literature about hospital capital structure(Shyam- Sunder & Myers, 1999), this study attempted comparison and analysis on whether the forecast of trade-off and pecking order theory could be validated in hospital's capital structure. First, this study analyzed whether hospitals follow the priority for each capital source as suggested by pecking order theory under lack of capital running in hospital. Next, it analyzed whether debt level is regressed on the average to target debt level so as to verify the validity of trade-off theory. Finally, it also analyzed possible associations between debt level and determinants of capital structure as adopted in static trade-off theory, so as to verify relative advantages of these two theories about hospital capital structure. The analysis over whole period showed that both trade-off theory and pecking order theory isn't supported particularly. This mean that each hospital's financing behaviors is different and that has not dominant financing behaviors. In the midst of separation of dispensary from medical practice, medical institutions in Korea first finances funds required using retained earnings and then use liabilities. however pecking order theory is supported, the preference of long-term liabilities and short-term liabilities is not clear. In addition, considering that debt level is in no average regression to target debt ratio, it is found that hospital capital structure following trade-off theory turns into that subject to pecking order theory via the separation of dispensary from medical practice.

• 한국콘텐츠학회논문지
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• 제14권11호
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• pp.102-110
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• 2014

본 연구는 공연여건의 성장에 걸 맞는 투자시스템으로의 변화를 모색하는 데 있다. 특히, 제작사들이 원하는 장기공연이나 오픈런 방식으로 공연여건이 조성되고 있는 상황에서 연장공연 여부를 신속히 판단할 수 있고, 제작자와 투자자 양자가 만족할 수 있는 미국식 예산수립 방식으로의 변화모색이 필요한 시점이다. 이에 구체적으로 3가지 방안을 제시하였다. 첫째, 연장공연이나 재공연 여부를 보다 정확히 판단하기 위해서는 현재와 같이 평균비용(Average Cost)을 산출하여 평균수입과 비교하기보다는 미국과 같이 한계비용(Marginal Cost)을 산출해서 비교해야 할 것이다. 둘째, 수익배분에 대한 불합리성을 극복하기 위해서는 현재와 같이 총제작비를 투자모수로 삼기보다는 미국과 같이 총제작비에서 운영비용(Operating Cost)을 제외한 프로덕션비용(Production Cost)만을 투자모수로 삼아야한다. 셋째, 앞서 언급한 한계비용의 산출과 프로덕션비용의 산출을 위해서는 미국 지출예산(Expense Budget)의 이원화 작성법의 국내 적용이 필요하겠다.

• Journal of Preventive Medicine and Public Health
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• 제5권1호
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• pp.105-110
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• 1972

On 6 healthy adult males aged 20-30 years, oxygen pulse was observed during carrying sand bags weighing 10, 20 and 30 kg on a level treadmill running with speeds of 3, 4 and 5 km/hr. The results obtained were as follows. 1. Oxygen pulse during load carrying on a level treadmill was proportionately increased with an increase of work load, average oxygen uptake per minute. Regression equation of oxygen pulse (y: $m\iota$/beat) on the average oxygen uptake (x:$\iota$/min) required for each grade of work was expressed as y=3.34x+5.99, $s_{y.x}=0.858$). 2. Oxygen pulse reached the highest value 2-5 minutes after the start of load carrying, and thereafter it decreased gradually to some extend as the load carrying was continued. Rate of decrease in the oxygen pulse was greater in lighter works. 3. In lighter works requiring less than $2.0\iota/min$ of oxygen uptake, no difference in oxygen pulse could be seen between methods of carrying even when the same amount of load was carried. In heavier works requiring more than $2.0\iota/min$ of oxygen uptake, oxygen pulse was larger in case of carrying a load by embrace, in both hands and on head than on back or on shoulder.

• 한국자동차공학회논문집
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• 제20권4호
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• pp.60-67
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• 2012

Most of a driving cycle is used to measure fuel consumption (FC) and emissions for a specified vehicle. A driving cycle was reflected geography and traffic characteristics for each country, also, driving pattern is affected these parameters such as vehicle dynamics, FC and emissions. Therefore, this study is an attempt to develop a driving cycle for military operational area. The proposed methodology the driving cycle using micro-trips extracted from real-world data. The methodology is that the driving cycle is constructed considering important parameters to be affected FC. Therefore, this approach is expected to be a better representation of heterogeneous traffic behavior. The driving cycle for the military operational area is constructed using the proposed methodology and is compared with real-world driving data. The running time and total distance of the final cycle is 1461 s, 13.10 km. The average velocity is 32.25 km/h and average grade is 0.43%. The Fuel economy in the final cycle is 5.93 km/l, as opposed to 6.10 km/l for real-world driving. There were about 3% differences in driving pattern between the final driving cycle and real-world driving.

• Archives of Plastic Surgery
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• 제39권3호
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• pp.238-243
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• 2012

Background : The publication rate of presentations at medical international meetings has ranged from 11% to 78% with an average of 45%. To date, there are no studies about the final rate of publications at scientific meetings associated with plastic surgery from Korea. The present authors investigated the publication rate among the presentations at meetings associated with plastic surgery. Methods : The titles and authors of the abstracts from oral and poster presentations were collected from the program books of the Congress of the Korean Society of Plastic and Reconstructive Surgeons (CKSPRS) for 2005 to 2007 (58th-63rd). All of the abstracts presented were searched for using PubMed, KoreaMed, KMbase, and Google Scholar. The titles, key words from the titles, and the authors' names were then entered in database programs. The parameters reviewed included the publication rate, type of presentation including running time, affiliation, subspecialty, time to publication, and publication journal. Results : A total of 1,176 abstracts presented at the CKSPRS from 2005 to 2007 were evaluated. 38.7% of the abstracts, of which oral presentations accounted for 41.0% and poster presentations 34.8%, were published as full papers. The mean time to publication was 15.04 months. Among journals of publication, the Journal of the Korean Society of Plastic and Reconstructive Surgeons was most used. Conclusions : Brilliant ideas and innovative approaches are being discussed at CKSPRS. The 38.7% publication rate found from this research appeared a bit lower than the average rate of medical meetings. If these valuable presentations are not available as full papers, the research would be a waste of time and effort.

• 한국태양에너지학회 논문집
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• 제28권3호
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• pp.7-14
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• 2008

400RT geothermal system which is the biggest capacity among on-operations at present in Korea is measured and evaluated on 23rd${\sim}$26th Jan. 2008 during those days building is not allowed owners and/or tenants to move in. The geothermal system is consist with vertical-typed 112 geothermal heat exchangers which are installed circle-like 1 row with 4m interval, and has 16 units of 25USRT geothermal-source heat pump(GSHP)s. And each 5 units of circulation pump are running for geothermal heat exchangers and hot water supplies. The followings are the results. The temperatures at G.L. -70m of 2 boreholes are varied quite similarly. The average temperature difference between inlet and outlet of geothermal pipes is $4.1^{\circ}C$, and that of hot water supply is $3.2^{\circ}C$, of Zone 3's each 4 GSHPs when being operated. Despite temperature fluctuations by heating loads, the average temperature difference between main pipes of inlet and outlet of geothermal heat exchangers is measured as $4.1^{\circ}C$. This study propose "Geothermal System COP" which includes not only consumed electric power by compressor but also circulation pumps and auxiliary utilities. By comparing the geothermal system COP with GSHP's performance specification, it is clear that the performances of GHSPs of this site are satisfied with the specification.

• 동아시아식생활학회지
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• 제17권6호
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• pp.765-779
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• 2007

The objective of this study was to examine Jeonju residents' recognition towards their native local foods. The results indicate that their degree of interest in the native foods was above average. As age and education increased, the degree of interest was also increased. Also, married people showed greater interest as compared to single people (p<$0.05{\sim}0.001$). There were more people who said they preferred native foods than people who said they didn't, where 213 people (41.3%) answered that they preferred the native foods. Of the people who said they like native foods, their main reason was because the native foods taste good. The main reason for the people who said they disliked native foods was that they didn't have many opportunities to try native foods. TV and radio were the first means, among others, from which people learned about native foods. The place where people ate native foods most often was native food restaurants (242 people, 46.95%). A frequency of a native food intake (including home and dining-out) of $1{\sim}2$ times/year was most prominent, with 137 people (26.6%). Also, a cooking frequency of "hardly ever cooks" was most prominent with 163 people (31.6%). The most prominent reason for the low cooking frequency at home was because they didn't know the recipes. Among 5 basic recipe characteristics for native foods (easy preparation of ingredients, simple recipe procedures, quick preparation, reasonable recipe procedures, sanitation), "sanitation" had the highest average score of 3.54, and "simple recipe procedure" had the lowest score of 2.44. To summarize, in order to develop Jeonju native local foods, it is necessary to implement various strategies such as frequently holding events where people can experience their native foods, running a native food training center, advertising through TV and radio, developing easy home recipes, and simplifying recipes.

• 한국정보과학회논문지:데이타베이스
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• 제30권4호
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• pp.362-371
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• 2003

이 논문에서는 이미지 데이타베이스에서 모양 특징 기반 이미지 분류와 인덱싱을 위해 객체의 윤곽선 특성을 고려해 임계값을 동적으로 결정하여 최적 우세점을 추출하는 알고리즘을 제안한다. 동적 임계값결정은 원본 모양의 윤곽선 길이 비와 근사화된 다각형의 둘레 길이 비를 알고리즘 수행시 점진적으로 검사하는 방법을 사용한다. 이 알고리즘은 윤곽선 특징을 반영하여 동적인 임계값 검사를 함으로써 의사점 수를 최대한 줄이며 최소 우세점만으로 모양 특징 정보를 추출할 수 있는 장점을 보인다. 제안한 방법은 객체의 윤곽선을 이루는 n개의 점에서 m개의 최적 우세점을 찾는데 평균 O(nlogn)이 걸린다. 최적화 평가는 7가지 서로 다른 특성을 가지는 70개의 합성 모양과 1,100개의 어류 모양에 대해 알고리즘을 적용하고 피 결과에 대해 평가 함수를 구성하여 수행하였다. 최적화율은 실험 모양들에 대해 평균0.92를 보였으며 기존 알고리즘에 대해 약 14% 최적화 성능 개선을 보였다. 제안한 알고리즘을 통해 추출한 모양 특징 정보는 정규화를 통해 이미지 분류와 인덱싱, 유사도 검색에 활용할 수 있다.