• 제목/요약/키워드: Yearly

검색결과 1,175건 처리시간 0.021초

대전원단지의 무효전력 출력제약에 따른 영향에 대한 연구 (A Study on the Improving Power System Reliability According to the Reactive Power Problem in the Bulk Power Station)

  • 송석하;주준영
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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    • pp.73-75
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    • 2002
  • This paper presents the properly method of system security and facility countermeasures. We performed simulation for yearly peak of Korean power system in 2002 under the reactive power problem in a nuclear power plants. Analysis of the problems in power system operation by power flow, fault and stability study. Establishment of power system optimal operating plan by stabilizer and maintaining the reasonable voltage level.

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잣나무 성숙 임분의 연도별 구과 및 종자 결실량에 미치는 국지기후의 영향 (Effects of Local Climatic Conditions on Yearly Cone and Seed Production in a Mature Stand of Korean Pine)

  • 신만용;김일현;김영채;전상근
    • 한국농림기상학회:학술대회논문집
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    • 한국농림기상학회 2001년도 춘계 학술발표논문집
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    • pp.131-134
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    • 2001
  • 잣나무는 목재생산뿐만 아니라 종자생산이라는 이중적 가치와 효용성을 지닌 주요 경제수종의 하나이다. 하지만 그 동안 대면적에 조성된 잣나무 임분은 인건비의 상승과 저가의 외국산 잣의 수입으로 인해 잣 생산을 통한 수익을 기대하기가 어려운 실정이 되었다. 따라서 잣나무림의 수익 증대를 위해서는 고품질의 종자와 양질의 목재를 증산시킬 수 있는 부가가치가 높은 임분으로의 유도가 필요하다.(중략)

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DEA를 이용한 종합병원의 효율성 평가 (Efficiency Evaluation of General Hospitals using DEA)

  • 박병상;이용균;김윤신
    • 한국콘텐츠학회논문지
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    • 제9권4호
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    • pp.299-312
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    • 2009
  • 병원은 이윤추구를 목적으로 하는 기업과 달리 공익성을 위하여 서비스를 제공하는 측면이 강하다. 하지만, 변화하는 의료환경 속에서 지속적인 성장을 위해서는 경영혁신이 필요하다. 병원의 경영혁신에서 핵심적인 내용은 효율성을 제고하는 것이다. 이를 위해 우선 병원 내부적으로 비효율성이 어떻게 나타나고 있으며 이에 영향을 미치는 요인이 무엇인지 파악하는 것이 필요하다. 그러나 병원의 효율성 평가는 민간부문에서 활용되고 있는 평가방식을 적용하기가 어렵다. 따라서 이 연구에서는 DEA 기법을 이용하여 종합병원의 효율성을 평가하였다. 국내 500병상이상 수련병원 74개를 대상으로 2006년 자료를 이용하여 분석하였다. 분석에 사용된 투입변수는 병상수, 의사수, 간호사수, 의료기사수, 인건비, 관리비, 재료비를 산출변수는 연외래환자수, 연입원환자수, 수술건수, 입원 및 외래 수익을 사용하였다. 또한 병원의 설립형태, 소재지, 설립년, 병원유형에 관해서 효율성에 어떤 영향이 미치는가에 대해서도 검토하였다.

인터넷과 소셜미디어를 통해 본 간호사 이미지에 관한 연구 (A Study of the Image of Nurse through Analysing Linking Words of Nurse in the Internet and Social Media)

  • 이현숙;이호선;염영희;이정민;정원선;박현정
    • 임상간호연구
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    • 제22권2호
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    • pp.173-182
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    • 2016
  • Purpose: This study investigated the linking words of nurse which were presented together with nurse on phrase, clauses or sentence of documents or conversations in the Internet portals and social media. Methods: The linking words with nurse were calculated by the number of presentation on conversations or documents, in Google, Daum, Naver, Twitter and Facebook. The changes of characteristics and the trend of yearly changes of major linking words of nurse were investigated by the type of media. In order to identify the meaning of the words, clustering of the collected linking words by categories was analysed and the characteristics of each cluster were classified. Results: A total number of reviewed linking words was 17,399,711 and the most frequently presenting words were hospital, work and person. The words related to people were the most highly presented and the next were those of emotion, professional and place respectively. Conclusion: With analysing the trends of changes and characteristics of words by yearly base and clusters, we attempted to investigate the image of nurse that the public think and feel about nurse.

단지계획지구 홍수저류지의 하천유지유량 공급방안 연구 (A Feasibility Study on Supplying Stream Minimum Flow Using Detention Storage in Developing Planned District)

  • 노재경;박현구
    • 한국수자원학회:학술대회논문집
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    • 한국수자원학회 2005년도 학술발표회 논문집
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    • pp.1219-1223
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    • 2005
  • This study was accomplished to confirm the possibility of supplying stream minimum flow from detention storage which was determined to reduce peak flows of flood within developing planned district. The results analyzed was summarized as follows; Firstly, Sin-gil district situated in Ansan city was selected, of which watershed area has $0.56km^2$. And detention storage was determined to $5,370m^3$ from analyzing flood volume by the SCS unit hydrograph method. Secondly, using Visual Basic ver 6.0, a detention storage water balance model was developed, in which simulation was based on conditioning storage inflow and outflow according to streamflow volume or rate state. And streamflow was simulated using the DAWAST model. Thirdly, detention operation scenarios were consisted of the combinations with inflow referencing streamflow of 5mm/day, 10mm/day and outflow referencing streamflow of 1mm/day, 2mm/day. The developed detention storage water balance model was operated to simulate daily water storages of detention sized on flood by scenarios. Stream minimum flows were able to be supplied during 209 days to 237 days per a year, total volume of stream minimum flows supplied for this period was analyzed to reach 27 to $55\% of yearly streamflow volume. If inflow criteria of streamflows to detention was considered to be established on a theoretical condition, it is expected to supply stream minimum flows of 20 to $30\% of yearly streamflow from stream to detention. Also to maximize function of supplying urban stream minimum flow from detention storages, sewage waters within developing planned district have to be treated and entered to detention inflow together with streamflows to enrich function of detention planned to reduce flood volumes.

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뇌졸중환자에 대한 연례보고(V) (Yearly Report on Cerebrovascular Accident Patients(V))

  • 고승희;전찬용;박종형
    • 대한한의학회지
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    • 제21권3호
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    • pp.129-139
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    • 2000
  • Clinical observation was made on 210 cases of CVA that were confirmed through brain CT, MRI scan and clinical observation. They were hospitalized in the oriental medical hospital of Kyungwon University from January to December in 1998. Objective : To evaluate the current status of cerebrovascular disease in Korea, we performed observation on stroke patients. Methods : We performed a retrospective study on 210 cases of stroke who had been admitted to the Dept. of Internal Medicine, College of Oriental Medicine, Kyungwon University from Jan. 1, 1998 to Dec. 31, 1998. Results : The incidence was highest in the patients with the age of above fifty. The frequency of strokes was similar between male and female cases. Ischemic stroke(70.0%) was more common than hemorrhagic stroke(20.5%), with transient ischemic attacks(9.5%) occuring less frequently. Middle cerebra! arterial territory was the most commonly involved site in ischemic strokes. Among intracerebral hemorrhages, putaminal hemorrhages were found in 69.8%, and was followed by IVH(9.3%), IVH with ICH(7.0%), subcortical hemorrhages (4.7%) and pontine hemorrhages(4.7%). The most ordinary preceding disease was hypertension. The next was diabetes mellitus. Most cases were given simultaneous treatment in both western and oriental medical methods. Conclusions : Generally it is thought that CVA occurs frequently in winter. But our observations reveal no such relationship. The predisposing factors of cerebral infarction were usually initiated during the time of resting and sleeping and those of cerebral hemorrhage chiefly during the time of exercising. I Patients whose condition of consciousness was bad at the time of admission tended to have a bad prognosis. This study suggests changing trends of stroke in Korea, and that a multicenter prospective study using stroke registry is required for confirmation.

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김치생산용 알타리무 전처리가공시스템 개발 (IV) - 시작기의 자동화와 평가 - (Development of the Altari Radish Pre-Processing System for Kimchi Production (IV) - Automation and Evaluation of the Prototype Machine -)

  • 민영봉;김성태;정태상;강동현;문성원
    • Journal of Biosystems Engineering
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    • 제31권2호
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    • pp.121-127
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    • 2006
  • An Altari radish pre-processing system, which feasible to process automatically such operations as leaf and root tail cutting and root peeling, for kimchi production was accomplished based on the foregone serial studies. In this study, the performances of the developed prototype machine, considered as a commercializing level, were analyzed and evaluated. The prototype machine attached Tiny PLC automatic control system was performed the sequent function as the rate of successful peeling was more than 98% for the Altari radish less than 70 mm diameter of a radish. The operating efficiency of this was 9 see/each, 128 kg/h, and it means as much as $5{\sim}6$ times that of a woman labor's. The sanitation and taste of the mechanized-processed Altari radish kimchi was almost same as that of the handmade. And they were suitable for manufactory of kimchi as the both short term ripening and storing kimchi. Developed machinery with one peeling device and two peeling devices that compared with hand processing, it was analyzed that the break-even yearly working days were 28 days and 19 days, and the break-even yearly processing amount were 28,700 kg, 32,400 kg, respectively.

한반도 대도시의 폭염 및 열대야 발생 특성에 대한 연구 (A Study on the Occurrence Characteristics of Tropical Night Day and Extreme Heat Day in the Metropolitan City, Korea)

  • 김은별;박종길;정우식
    • 한국환경과학회지
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    • 제23권5호
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    • pp.873-885
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    • 2014
  • To identify the characteristics of extreme heat events and tropical nights in major cities, the correlations between automated synoptic observing station (ASOS), automatic weather station (AWS), and temperature in seven metropolitan areas were analyzed. Temperatures at ASOS were found to be useful sources of the reference temperature of each area. To set the standard for identifying dates of extreme heat events in relation to regional topography and the natural environment, the monthly and yearly frequency of extreme heat in each region was examined, based on the standards for extreme heat day (EHD), tropical night day (TND), and extreme heat and tropical night day (ETD). All three cases identified 1994 as the year with the most frequent heat waves. The frequency was low according to all three cases in 1993, 2003 and 2009. Meanwhile, the yearly rate of increase was the highest in 1994, followed by 2010 and 2004, indicating that the frequency of extreme heat changed significantly between 1993 and 1994, 2003 and 2004, and 2009 and 2010. Therefore all three indexes can be used as a standard for high temperature events. According to monthly frequency data for EHD, TND, and ETD, July and August accounted for 80% or more of the extreme heat of the entire year.

자연형 태양열주택 난방시스템의 경제적 평가 (Economic Evaluation of the Passive Solar-house Heating System Using the All-glass Evacuated Solar Collector Tubes and the Pebble Bed Heat Storage)

  • 장문기;;리신호
    • 한국농공학회논문집
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    • 제50권3호
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    • pp.43-48
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    • 2008
  • The economics of a passive solar heating system (PSHS) with the pebble bed heat storage was evaluated, and the applications of the PSHS were analyzed, in this study. The results are as follows: The heating load, solar heat gain, and stored heat/year of the PSHS in the solar house model were found to be 10,778MJ, 3,438MJ, and 11,682MJ, respectively. The yearly energy expenses of the PSHS and the alternative heating system (conventional coal heating system, CCHS), which uses coal, were found to be USD 1.60/year and USD 60.90/year, respectively, and the yearly expenses of the PSHS were found to be 38 times less than those of the alternative heating system (CCHS). If it will be supposed that the life cycle of the passive solar heating system, according to the results of the LCC analysis in the two systems, is 40 years, the total expenses for the life cycle of the PSHS and the CCHS will be USD 1,431.50 and USD 2,740.00, respectively. The period for the investment payback of the PSHS is six years.

낙동강 하구 해양환경 및 기상 요인이 김P(orphyra yezoensis) 생산량 변화에 미치는 영향 (Effects of Meteorological and Oceanographic Properties on Variability of Laver Production at Nakdong River Estuary, South Coast of Korea)

  • 권정노;심정희;이상용;조진대
    • 한국수산과학회지
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    • 제46권6호
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    • pp.868-877
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    • 2013
  • To understand the effects of marine environmental and meteorological parameters on laver Porphyra yezoensis production at Nakdong River Estuary, we analyzed marine environmental (water temperature, salinity, nutrients, etc.) and meteorological properties (air temperature, wind speed, precipitation, sunshine hours) with yearly and monthly variations in laver production over 10 years (2003-2013). Air and water temperature, wind speed, sunshine hours and precipitation were major factors affecting yearly variability in laver production at the Nakdong River Estuary. Lower air and water temperatures together with higher levels of nutrients and sunshine and stronger wind speeds resulted in higher laver harvests. Salinity and nitrogen did not show clear correlations with laver production, mainly due to the plentiful supply of nitrogen from river discharge and the low frequency of environmental measurements, which resulted in low statistical confidence. However, environmental factors affecting monthly laver production were related to the life cycle (culturing stage) of Porphyra yezoensis and were somewhat different from factors affecting annual laver production. In November, a young laver needs lower water temperatures for rapid growth, while a mature laver needs much stronger winds and more sunshine, as well as lower temperatures for massive production and effective photosynthesis, mostly in December and January. However, in spring (March), more stable environments with fewer fluctuations in air temperature are needed to sustain the production of newly deployed culture-nets ($2^{nd}$ time culture). These results indicate that rapid changes in weather and marine environments caused by global climate change will negatively affect laver production and, thus, to sustain the yield of and predict future variability in laver production at the Nakdong River estuary, environmental variation around laver culturing farms needs to be monitored with high resolution in space and time.