• 제목/요약/키워드: term distribution

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천수만의 수질환경특성과 장기변동 (Long-term Changes and Variational Characteristics of Water Quality in the Cheonsu Bay of Yellow Sea, Korea)

  • 박승윤;박경수;김형철;김평중;김전풍;박중현;김숙양
    • 한국환경과학회지
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    • 제15권5호
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    • pp.447-459
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    • 2006
  • Long-term trends and distribution patterns of water quality were investigated in the Cheonsu Bay of Korea from 1983 to 2004. Water samples were collected at 4 stations and physicochemical parameters were analyzed including water temperature, salinity, suspended solids (SS), chemical oxygen demand (COD), dissolved oxygen (DO) and nutrients. Spatial distribution patterns were not clear between stations but the seasonal variations were distinctive except COD, SS and nitrate. Twenty two year long-term trend analysis by PCA revealed the significant changes in water quality in the study area. Water quality during 1980's and early 1990's showed high SS, low nutrients and low COD which increased during the mid and late 1990's and early 2000's. Overall water duality in the Cheonsu Bay indicated the increase in nutrients and COD concentration.

The Effects of Self-Referencing and Counteractive Construal on Consumption Goal Reversion

  • Choi, Nak-Hwan;Liu, Cong;Mu, Peipei
    • 유통과학연구
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    • 제12권3호
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    • pp.7-15
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    • 2014
  • Purpose - This study aims to explore the factors that can trigger the escalation of an initially pursued long-term utilitarian goal that is set aside to pursue a competing hedonic goal. Research Design, Data, and Methodology - The experimental study covered three groups : Group 1 (ego-depletion, self-referencing), Group 2 (ego-depletion, neutral), and Group 3 (no ego-depletion, neutral). The participants of the study comprised 150 undergraduates who were divided into three groups of 50 students for each. One-way ANOVA and regression analyses were used to verify the hypotheses. Results - Ego-depleted consumers are less likely to resist immediate temptation than those who are not in an ego-depletion state. Self-referencing has a positive impact on long-term goal reversion when consumers in an ego-depletion state experience immediate temptations. Counteractive construal plays a mediating role between self-referencing and long-term goal reversion. Conclusions - We found that consumers tend to yield to momentary temptations when they are in an ego-depletion state. Self-referencing and counteractive construal can eliminate the ego-depletion effect and then facilitates escalation of the set-aside long-term goal.

우리나라 연안의 기온과 수온 분포함수 추정 및 비교평가 (Estimation and Comparative Analysis on the Distribution Functions of Air and Water Temperatures in Korean Coastal Seas)

  • 조홍연;정신택
    • 한국해안·해양공학회논문집
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    • 제28권3호
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    • pp.171-176
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    • 2016
  • 기온과 수온의 분포형태는 발생빈도의 양상을 결정하는 기본적이고 필수적인 정보이다. 또한 기후변화에 의한 기온과 수온의 장기변화 양상 파악에 유용하다. 기온과 수온의 전형적인 분포형태는 다수의 첨두(mode)를 가지는 형태로 일반적으로 널리 사용되는 정규분포로 표현하기에는 한계가 있다. 본 연구에서는 Gaussian 혼합함수와 Kernel 분포함수를 보다 기온과 수온의 보다 적합한 분포함수 형태로 제안한다. 제안된 분포함수를 우리나라 연안 기온과 수온자료를 이용하여 추정-평가한 결과, 관측 자료의 분포는 꼬리 영역에서 크게 차이를 보이고 있는 것으로 파악되었다. 높은 수온영역과 낮은 기온 영역에서 꼬리 영역이 길게 나타나고 있다. 또한 본 연구에서 제안한 분포함수 추정 및 비교는 기온과 수온의 상호 변동관계 및 장기적인 변동양상을 파악할 수 있다. 그러나 평균 기온 및 수온 그리고 정규분포 함수 형태로는 이러한 변화 양상의 파악은 크게 제한되고 있다.

의사인력의 지역간 분포양상 및 공중보건의사의 영향 (Geographical Distribution of Physician Manpower under the Influence of Public Health Physician)

  • 서용덕;차병준;박재용
    • 보건행정학회지
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    • 제3권2호
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    • pp.81-99
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    • 1993
  • The purpose of this research is to assess the geographical distribution of physicians and dentists and the degree of maldistribution of the physician. Data were obtained form the Korean Medical Association's report on physicians registry and census for 1990. To assess the degree of disparity in the rural-urban distribution of physician manpower and to identify changes in the distribution pattern, the Gini index of concentration was used. Major findings are as follows; 1. Urban-rural disparity in the distribution of physician manpower exists in all categories of manpower, i.e. physician, dentist, oriental medical doctor, general practitioner, medical specialist, practitioner, public health physician and public health dentist. Urban area which had 74.4% of nation's population, accounted for over 90% of all physician manpower. 2. In terms of the ration of physician manpower per 10, 000 population, in urban area, they were 8.2 physicians, 2.7 general practitioners, 5.5 specialists, 3.0 practitioners, 1.8 dentists and 1.3 oriental medical doctors. In rural area, the ratios were 1.4 physicians, 0.6 general practitioners, 0.9 specialists, 1.0 practitioners, 0.4 dentists and 0.4 oriental medical doctors. 3. Gini indicies computed to measure inequality of physician manpower distribution were 0. 3675 for physicians, 0.3372 for general practitioners, 0.3338 for specialists, 0.2263 for practitioners, 0.3132 for dentists and 0.3293 for oriental medical doctors. 4. Inspite of increase in the number of physician manpower, urban concentration of physician manpower intensified from 1980 to 1990. However, the Gini index for all physician manpower fell by 18.3~36.7% from 1980 to 1990, indicating more even distribution. 5. In rural area, the public health physicians and dentists had increased the ratios of physicians, general practitioners, practitioners and dentists per 10, 000 population remarkebly, and had decreased the Gini indicies of physicians, general practitioners, practitioners and dentists. Thus, public health physicians and dentists contributed to improve the distribution of physician manpower in rural area. Based on the results of this study, long-term and rational manpower policies should be developed to solve the problem of geographical maldistribution of physician manpower as well as short-term policy for inducing physicians to the rural areas.

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Numerical Simulation of Die Compaction: Case Studies and Guidelines

  • Coube, Olivier
    • 한국분말야금학회:학술대회논문집
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    • 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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    • pp.185-186
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    • 2006
  • Numerical Simulation of powder die pressing is conducted on Case Study geometry. Influence of fill density distribution and punch kinematics upon green density distribution and punch loading are studied and discussed. Deviations in punch kinematics due to punch deflection influence the most the results in term of density and force.

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무의 중기 선행관측모형 개발 (Development of a mid-term preceding observation model for radish)

  • 조재환;이한성
    • 농업과학연구
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    • 제38권3호
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    • pp.571-581
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    • 2011
  • This study develops a mid-term preceding observation model of radish to complement an existing short-term agricultural observation model. The first purpose of the study is to extend a three seasonal classification(spring, summer, fall) of fruit-vegetables to a four seasonal classification that involves the winter additionally. This allows us to verify the reason for demand and supply unbalance and unstable price of radish. The second purpose is to construct a mid-term preceding observation model that would be used to forecast planted areas, output, monthly shipment and price. To achieve these purposes, several multiple regression models are estimated. A system is consisted of a planted areas equation, a yield equation, monthly shipment distribution equation, and monthly price equation. To calculate output an auxiliary equation is involved in the system and the consumer price index etc are considered as exogenous variables.

추계적 공동주택 장기수선충당금 산출 및 분석 방법론 개발 (Developing Stochastic Long-Term Maintenance Cost Estimating Method for Apartment Housing)

  • 곽한성;이동은
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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    • pp.243-244
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    • 2015
  • This paper presents a Stochastic Long-Term Maintenance Costs Estimating Method for the Apartment Housing (SLCE). A simulation approach is used for generating the stochastic long-term maintenance cost, and it is based on the defined variability in repair cycle of the individual maintenance elemental within the process. SLCE provides the probability distribution of the budget required to maintain the apartment housing. A case study is presented to demonstrate and to validate the system.

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비정상성 분위사상법을 이용한 GCM 장기예측 편차보정 (Bias Correction for GCM Long-term Prediction using Nonstationary Quantile Mapping)

  • 문수진;김정중;강부식
    • 한국수자원학회논문집
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    • 제46권8호
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    • pp.833-842
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    • 2013
  • 분위사상법(QM, Quantile Mapping)은GCM(Global Climate Model) 자료의 계통적 오차를 보정하여 보다 신뢰성 높은 자료로 재생성하기 위해 활용되고 있다. 이 기법은 사상(mapping)시키려는 대상(object) 자료의 통계분포모수가 정상적(stationarity)이라는 가정 하에 대상 자료의 누적확률분포(CDF, Cumulative Distribution Function)를 목표(target) CDF에 통계적으로 투영시키는 것이 일반적이다. 따라서 GCM에서 제공되는 미래 기후시나리오의 강우시계열과 같이 비정상성(non-stationarity)을 갖는 장기 시계열자료에 대한 적용에는 문제점을 보이고 있다. 본 연구에서는 비정상성을 갖는 장기시계열자료의 오차보정을 위해 통계분포모수에 경향성을 부여하는 비정상성 분위사상법(NSQM, Nonstationary Quantile Mapping)을 적용하였다. NSQM 적용을 위한 확률분포로 수문분야에서 광범위하게 쓰이고 있는Gamma 분포를 선정하였으며, 대상 시나리오는 CCCma (Canadian Centre for Climate modeling and analysis)에서 제공하고 있는 CGCM3.1/T63모형의 20C3M(reference scenario)과 SRES A2 시나리오(projection scenario)를 활용하였다. 한강유역 내 관측기간이 충분한 10개의 지상관측소로부터 강우량을 수집하였다. 또한 6월과 10월사이에 연 강수량의 65% 이상이 집중되는 한반도의 계절성을 반영하기 위해 홍수기(6~10월)와 비홍수기(11~5월)를 구분하였고, 기준기간(Baseline)은 1973~2000년, 전망기간(Projection)은 2011~2100년으로 구분하였다. 다양한 목표분포의 설정을 통하여 NSQM의 적용성을 평가하고자 하였으며, 전망기간은 FF시나리오(Foreseeable Future Scenario, 2011~2040년), MF시나리오(Mid-term Future Scenario, 2041~2070년), LF시나리오(Long-term Future Scenario, 2071~2100년)의 3개의 구간으로 설정하여 기준기간과 전망기간의 연평균 강우량에 대한 경향성분석을 실시하였다. 그 결과NSQM이 FF시나리오에서 330.1mm(25.2%), MF시나리오에서 564.5mm(43.1%), LF시나리오에서 634.3mm(48.5%)로 증가하는 전망결과를 나타내고 있었다. 정상성기법을 적용한 결과, 전망기간 중 전체적으로는 동일한 평균값을 갖는 목표통계모수를 사용한다고 하여도, 전망전반부에서 과다하고, 후반부에서 오히려 과소한 전망을 보여주고 있었다. 이러한 결과는 비정상성기법을 사용함으로써 상당부분 개선될 수 있음을 확인하였다.

장기유출의 수문적 모형개발을 위한 주요 수계별 단위도 유도 (Determination of Unit Hydrograph for the Hydrological Modelling of Long-term Run-off in the Major River Systems in Korea)

  • 엄병현;박근수
    • 한국농공학회지
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    • 제26권4호
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    • pp.52-65
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    • 1984
  • In general precise estimation of hourly of daily distribution of the long-term run-off should be very important in a design of source of irrigation. However, there have not been a satisfying method for forecasting of stationar'y long-term run-off in Korea. Solving this problem, this study introduces unit-hydrograph method frequently used in short-term run-off analysis into the long-term run-off analysis, of which model basin was selected to be Sumgin-river catchment area. In the estimation of effective rainfall, conventional method neglects the Soil moisture condition of catchment area, but in this study, the initial discharge (qb) occurred just before rising phase of the hydrograph was selected as the index of a basin soil moisture condition and then introduced as 3rd variable in the analysis of the reationship between cumulative rainfall and cumulative loss of rainfall, which built a new type of separation method of effective rainfall. In next step, in order to normalize significant potential error included in hydrological data, especially in vast catchment area, Snyder's correlation method was applied. A key to solution in this study is multiple correlation method or multiple regressional analysis, which is primarily based on the method of least squres and which is solved by the form of systems of linear equations. And for verification of the change of characteristics of unit hydrograph according to the variation of a various kind of hydrological charateristics (for example, precipitation, tree cover, soil condition, etc),seasonal unit hydrograph models of dry season(autumn, winter), semi-dry season (spring), rainy season (summer) were made respectively. The results obtained in this study were summarized as follows; 1.During the test period of 1966-1971, effective rainfall was estimated for the total 114 run-off hydrograph. From this estimation results, relative error of estimation to the ovservation value was 6%, -which is mush smaller than 12% of the error of conventional method. 2.During the test period, daily distribution of long-term run-off discharge was estimated by the unit hydrograph model. From this estimation results, relative error of estimation by the application of standard unit hydrograph model was 12%. When estimating by each seasonal unit bydrograph model, the relative error was 14% during dry season 10% during semi-dry season and 7% during rainy season, which is much smaller than 37% of conventional method. Summing up the analysis results obtained above, it is convinced that qb-index method of this study for the estimation of effective rainfall be preciser than any other method developed before. Because even recently no method has been developed for the estimation of daily distribution of long-term run-off dicharge, therefore estimation value by unit hydrograph model was only compared with that due to kaziyama method which estimates monthly run-off discharge. However this method due to this study turns out to have high accuracy. If specially mentioned from the results of this study, there is no need to use each seasonal unit hydrograph model separately except the case of semi-dry season. The author hopes to analyze the latter case in future sudies.

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The role of Patent on Foreign Direct Investment: Evidence in Vietnam

  • PHAM, Nga Thi;PHAM, Huong Thi Thu
    • 유통과학연구
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    • 제18권6호
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    • pp.77-82
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    • 2020
  • Purpose: In the period of international integration, how is the implementation of intellectual property regulation in developing countries? Do intellectual property rights help attract more Foreign direct investment (FDI)? This study aims to show the effect of intellectual property rights, reflect in the number of patent registered (Patent distribution into two components: Patent_residents and Patent_non-residents) on FDI attraction in Vietnam. Research design, data and methodology: Using Autoregressive distributed lag (ARDL) model for the data collected from 1990 to 2018 with EViews version 9 software. Conclusions: The results indicate that the number of patent protection has a positive effect on FDI in both short term and long term. In particular, only patent registration of foreign individuals and organizations has a significant positive effect on attracting FDI, while that of Vietnamese patents is not statistically significant. From the results of this study, we provide some recommendations to help attract FDI based on raising awareness of intellectual property rights: Increase international cooperation for innovation to learn and encourage patent; Improve the capac ity of inventing as well as the ability to register patents of Vietnamese people; Government agencies are tasked to support a nd review registration procedures; Encouraging patent registration based on the patent.