• 제목/요약/키워드: future distribution

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LH-Moments of Some Distributions Useful in Hydrology

  • Murshed, Md. Sharwar;Park, Byung-Jun;Jeong, Bo-Yoon;Park, Jeong-Soo
    • Communications for Statistical Applications and Methods
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    • 제16권4호
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    • pp.647-658
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    • 2009
  • It is already known from the previous study that flood seems to have heavier tail. Therefore, to make prediction of future extreme label, some agreement of tail behavior of extreme data is highly required. The LH-moments estimation method, the generalized form of L-moments is an useful method of characterizing the upper part of the distribution. LH-moments are based on linear combination of higher order statistics. In this study, we have formulated LH-moments of five distributions useful in hydrology such as, two types of three parameter kappa distributions, beta-${\kappa}$ distribution, beta-p distribution and a generalized Gumbel distribution. Using LH-moments reduces the undue influences that small sample may have on the estimation of large return period events.

차세대 배전지능화시스템 개발을 위한 지리정보시스템 적용 (Geographic Information System for Developing Advanced Distribution Management System)

  • 김동욱;조성호;서호진;박영배
    • KEPCO Journal on Electric Power and Energy
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    • 제5권2호
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    • pp.67-74
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    • 2019
  • 최근 신재생 분산전원의 투입 확대로 배전계통 내 변동성이 커짐에 따라서 안정적인 배전계통 운영에 대한 우려가 커지고 있는 상황이다. 미래 배전계통의 효율적인 관리를 위해서 새로운 시각화 기술을 이용한 배전계통 운영시스템의 개선이 필요하다. 본 논문에서는 배전분야의 GIS 도입 현황과 관련 기술 동향을 기술하고, 배전계통 운영을 위해 GIS시스템의 필요성과 GIS기술 도입 시 해결해야할 문제점을 분석한다.

ON-LINE CALCULATION OF 3-D POWER DISTRIBUTION

  • Park, Y. H.;W. K. In;Park, J. R.;Lee, C. C.;G. S. Auh
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1996년도 춘계학술발표회논문집(1)
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    • pp.459-464
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    • 1996
  • The 3-D power distribution synthesis scheme was implemented in Totally Integrated Core Operation Monitoring System (TICOMS), which is under development as the next generation core monitoring system. The on-line 3-D core power distribution obtained from the measured fixed incore detector readings is used to construct the hot pin power as well as the core average axial power distribution. The core average axial power distribution and the hot pin power of TICOMS were compared with those of the current digital on-line core monitoring system, COLSS, which construct the core average axial power distribution and the pseudo hot pin power. The comparison shows that TICOMS results in the slightly more accurate core average axial power distribution and the less conservative hot pin power. Therefore, these results increased the core operating margins. In addition, the on-line 3-D power distribution is expected to be very useful for the core operation in the future.

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미래 기상 시나리오에 대한 편의 보정 방법에 따른 지역 기후변화 영향 평가의 불확실성 (Uncertainty in Regional Climate Change Impact Assessment using Bias-Correction Technique for Future Climate Scenarios)

  • 황세운;허용구;장승우
    • 한국농공학회논문집
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    • 제55권4호
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    • pp.95-106
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    • 2013
  • It is now generally known that dynamical climate modeling outputs include systematic biases in reproducing the properties of atmospheric variables such as, preciptation and temerature. There is thus, general consensus among the researchers about the need of bias-correction process prior to using climate model results especially for hydrologic applications. Among the number of bias-correction methods, distribution (e.g., cumulative distribution fuction, CDF) mapping based approach has been evaluated as one of the skillful techniques. This study investigates the uncertainty of using various CDF mapping-based methods for bias-correciton in assessing regional climate change Impacts. Two different dynamicailly-downscaled Global Circulation Model results (CCSM and GFDL under ARES4 A2 scenario) using Regional Spectial Model for retrospective peiod (1969-2000) and future period (2039-2069) were collected over the west central Florida. Total 12 possible methods (i.e., 3 for developing distribution by each of 4 for estimating biases in future projections) were examined and the variations among the results using different methods were evaluated in various ways. The results for daily temperature showed that while mean and standard deviation of Tmax and Tmin has relatively small variation among the bias-correction methods, monthly maximum values showed as significant variation (~2'C) as the mean differences between the retrospective simulations and future projections. The accuracy of raw preciptiation predictions was much worse than temerature and bias-corrected results appreared to be more significantly influenced by the methodologies. Furthermore the uncertainty of bias-correction was found to be relevant to the performance of climate model (i.e., CCSM results which showed relatively worse accuracy showed larger variation among the bias-correction methods). Concludingly bias-correction methodology is an important sourse of uncertainty among other processes that may be required for cliamte change impact assessment. This study underscores the need to carefully select a bias-correction method and that the approach for any given analysis should depend on the research question being asked.

Liver Cancer Mortality Characteristics and Trends in China from 1991 to 2012

  • Fang, Jia-Ying;Wu, Ku-Sheng;Zeng, Yang;Tang, Wen-Rui;Du, Pei-Ling;Xu, Zhen-Xi;Xu, Xiao-Ling;Luo, Jia-Yi;Lin, Kun
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권5호
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    • pp.1959-1964
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    • 2015
  • Purpose: To investigate the distribution of liver cancer mortality as well as its developing trend from 1991 to 2012, forecast the future five-year trend, and provide a basis for the comprehensive prevention and management. Materials and Methods: Mortality data for liver cancer in China from 1991 to 2012 were used to describe characteristics and distribution of liver cancer mortality. Trend surface analysis was used to study the geographical distribution of liver cancer mortality. Curve estimation, time series modeling, gray modeling (GM) and joinpoint regression were used to predict and forecast future trends. Results: The mortality rate of liver cancer has constantly increased in China since 1991. Rates in rural areas are higher than in urban areas, and in males are higher than in females. In addition, our data predicted that the trend will continue to increase in the next 5 years. The age-specific mortality of liver cancer increases with age and peaks in the group of 80-84 years old. Geographical analysis showed the liver mortality rate was higher in the southeast provinces, such as Jiangsu, Zhejiang and Guangdong, and southwest regions like Guangxi Province. Conclusions: The standardized mortality rate of liver cancer in China has consistently increased from 1991 to 2012, and the upward trend is predicted to continue in the future. Much better prevention and management of liver cancer is needed in high mortality areas (the southwestern and southeastern parts of China) and high mortality age groups (80- to 84-year-olds), especially in rural areas.

한국 소매점에서의 비주얼머천다이징 개념 정리와 방향 (A Study on the Concepts and its Vision for Visual Merchandising in Korean Retail Shops)

  • 서정화;윤명길
    • 유통과학연구
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    • 제14권8호
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    • pp.153-160
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    • 2016
  • Purpose - The current distribution enterprises have realized the necessity for integrated and specialized images in their stores. From those reasons, visual merchandising has been considered as a powerful means towards brand value judgement as well as maximizing both brand and corporate identity. This research intends to study and discuss the current situations in Korean visual merchandising and its future concept setting. Based on the research findings, this paper tries to propose the basic concept for development strategies of visual merchandising in Korean distribution market. Although the studies on visual merchandising in Korean traditional markets have been continued, visual merchandisers have been distorted by display control centers in real situations. Therefore, this study tries to set both current and future concepts in visual merchandising for further discussions and a new complement formulation. Research design, data, and methodology - This study has investigated previous studies with the way of normative study by comparing, organizing concepts and relating terms on visual merchandising. In order to be an exact research, it seems to be more appropriate to analyze this study with a deductive analysis way rather than inductive as for getting the core of visual merchandising. Besides, this study changed the term 'visual merchandising' into 'VMD', and used it as an unified one. Results - Visual merchandising has an important key in retail planning. With focusing on organizing visual merchandising concepts, it should be adequate for domestic circumstances because there are various visual merchandising concepts with different perspectives. Thus, it is necessary to establish a concept including modern and Korean features through previous studies and data. Visual merchandising can be defined as followings. It enhances the value of shop images from visual aspects and conveys brand concepts effectively. Its task is to plan and manage products sales by combining three merchandising domains such as interior, display, and merchandising. Conclusions - There are some limitations on setting academic concepts in visual merchandising due to its features as to be taken in the field focused studies. More meaningful case studies should be performed as an area of future studies. Therefore, it is necessary to perform an effectiveness analysis on empirical visual merchandising state and present the course of development.