• Title/Summary/Keyword: forecasts

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Facts and Forecasts in Packaging Industry and Education in China (중국의 포장산업 및 교육의 현실과 전망)

  • Kim, Jai-Neung;Kim, Jong-Kyoung
    • KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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    • v.8 no.2
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    • pp.6-11
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    • 2002
  • China has witnessed tremendous changes especially in the field of packaging industry after the reform and opening policy commencing in early 1979. Thanks to the reform and opening policy by Deng Xiaoping, a former leader of China, packaging industry has been selected as one of the specialized industries, and this policy has made great achievements in the field of packaging. The total volume of packaging industry now ranks the first in the overall industry in China and this indicates that this industry is taking a great role to bust up economic growth of China. In this paper, The facts and forecasts of packaging industry and education in China are introduced.

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Predictability Experiments of Fog and Visibility in Local Airports over Korea using the WRF Model

  • Bang, Cheol-Han;Lee, Ji-Woo;Hong, Song-You
    • Journal of Korean Society for Atmospheric Environment
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    • v.24 no.E2
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    • pp.92-101
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    • 2008
  • The objective of this study is to evaluate and improve the capability of the Weather Research and Forecasting (WRF) model in simulating fog and visibility in local airports over Korea. The WRF model system is statistically evaluated for the 48-fog cases over Korea from 2003 to 2006. Based on the 4-yr evaluations, attempts are made to improve the simulation skill of fog and visibility over Korea by revising the statistical coefficients in the visibility algorithms of the WRF model. A comparison of four existing visibility algorithms in the WRF model shows that uncertainties in the visibility algorithms include additional degree of freedom in accuracy of numerical fog forecasts over Korea. A revised statistical algorithm using a linear-regression between the observed visibility and simulated hydrometeors and humidity near the surface exhibits overall improvement in the visibility forecasts.

Prospects for the Management of Shanghai Harbour

  • He Yegang
    • Proceedings of the KOR-KST Conference
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    • 1993.07a
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    • pp.99-105
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    • 1993
  • This Article analyses the present situation of Shanghai Harbour and the Harbour's important role in the development of chinese economy. The article forecasts that the yearly tonnage turnover of the port will reach about 200 million tons in the year of 2000, possibly reach to 270--300 million tons by the end of 2020. it also forecasts that the container handling capacity of the port will be 2 million TEUS in 2000 and 6 million TEUS in 2020 respectively. In order to keep pace with the present situation of opening up and developing Pudong new area, this article suggests that the strategic target of the management and development of Shanghai Harbour should be : grasp the opportunity of opening up and developing Pudong, take the building of the deep-waterway port as the main task, which can accept the third or fourth generation international container ships, bring into full play the traditional advantages the Harbour has, unfold the businesses in other fields, participate in the marketing competition, speed up the development of the Harbour itself, make efferts to build Shanghai Harbour into a port-industry-trade-transportation integral modernized international deep-water key port.

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Development of Multi-Ensemble GCMs Based Spatio-Temporal Downscaling Scheme for Short-term Prediction (여름강수량의 단기예측을 위한 Multi-Ensemble GCMs 기반 시공간적 Downscaling 기법 개발)

  • Kwon, Hyun-Han;Min, Young-Mi;Hameed, Saji N.
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1142-1146
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    • 2009
  • A rainfall simulation and forecasting technique that can generate daily rainfall sequences conditional on multi-model ensemble GCMs is developed and applied to data in Korea for the major rainy season. The GCM forecasts are provided by APEC climate center. A Weather State Based Downscaling Model (WSDM) is used to map teleconnections from ocean-atmosphere data or key state variables from numerical integrations of Ocean-Atmosphere General Circulation Models to simulate daily sequences at multiple rain gauges. The method presented is general and is applied to the wet season which is JJA(June-July-August) data in Korea. The sequences of weather states identified by the EM algorithm are shown to correspond to dominant synoptic-scale features of rainfall generating mechanisms. Application of the methodology to seasonal rainfall forecasts using empirical teleconnections and GCM derived climate forecast are discussed.

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Optimal Multi-Model Ensemble Model Development Using Hierarchical Bayesian Model Based (Hierarchical Bayesian Model을 이용한 GCMs 의 최적 Multi-Model Ensemble 모형 구축)

  • Kwon, Hyun-Han;Min, Young-Mi;Hameed, Saji N.
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1147-1151
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    • 2009
  • In this study, we address the problem of producing probability forecasts of summer seasonal rainfall, on the basis of Hindcast experiments from a ensemble of GCMs(cwb, gcps, gdaps, metri, msc_gem, msc_gm2, msc_gm3, msc_sef and ncep). An advanced Hierarchical Bayesian weighting scheme is developed and used to combine nine GCMs seasonal hindcast ensembles. Hindcast period is 23 years from 1981 to 2003. The simplest approach for combining GCM forecasts is to weight each model equally, and this approach is referred to as pooled ensemble. This study proposes a more complex approach which weights the models spatially and seasonally based on past model performance for rainfall. The Bayesian approach to multi-model combination of GCMs determines the relative weights of each GCM with climatology as the prior. The weights are chosen to maximize the likelihood score of the posterior probabilities. The individual GCM ensembles, simple poolings of three and six models, and the optimally combined multimodel ensemble are compared.

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Climate Information and GCMs Seasonal Forecasts Based Short-term Forecasts for Drought (기상자료 및 GCMs 예측결과를 활용한 단기 가뭄 예측)

  • Kwon, Hyun-Han;Moon, Jang-Won;Song, Hyun-Sup;Moon, Young-Il
    • Proceedings of the Korea Water Resources Association Conference
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    • 2009.05a
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    • pp.1186-1190
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    • 2009
  • 강수량이 예년에 비해 적은 양상은 여름강수량에 대한 부족으로 기인한다. 우리나라의 경우 장마기간의 강수와 태풍으로 인해 발생하는 강수가 전체 강수량에 많은 부분을 차지하고 있기 때문에 여름강수량이 적게 나타나게 되면 가을 가뭄 및 봄 가뭄에 대한 발생 압력도 그 만큼 커지게 되는 것이 일반적이다. 기존 연구들이 단순히 강수량을 가정하거나 시나리오를 기반으로 가뭄을 전망하는데 그치고 있으나 본 연구에서는 2009년 가뭄전망을 위해서 전지구기후모형(GCMs)의 3개월 기상예측 결과를 활용하고자 한다. 즉, APEC 기후예측 센터로부터 제공 받은 3개월 GCM Multi-Model Ensemble 예측 결과를 바탕으로 가뭄상태를 평가하였다. 따라서 본 연구의 목적은 Large-scale의 기후예측 시스템과 기상관측지점의 강수 및 온도를 연결시켜 가뭄을 전망할 수 있는 시스템을 구축하는데 있다. GCM 예측 결과를 바탕으로 2009년도 매월 강수량 및 평균 온도를 추정하여 PDSI 가뭄지수 산정에 이용하였다.

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The 3-hour-interval prediction of ground-level temperature using Dynamic linear models in Seoul area (동적선형모형을 이용한 서울지역 3시간 간격 기온예보)

  • 손건태;김성덕
    • The Korean Journal of Applied Statistics
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    • v.15 no.2
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    • pp.213-222
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    • 2002
  • The 3-hour-interval prediction of ground-level temperature up to +45 hours in Seoul area is performed using dynamic linear models(DLM). Numerical outputs and observations we used as input values of DLM. According to compare DLM forecasts to RDAPS forecasts using RMSE, DLM improve the accuracy of prediction and systematic error of numerical model outputs are eliminated by DLM.

Coherent Forecasting in Binomial AR(p) Model

  • Kim, Hee-Young;Park, You-Sung
    • Communications for Statistical Applications and Methods
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    • v.17 no.1
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    • pp.27-37
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    • 2010
  • This article concerns the forecasting in binomial AR(p) models which is proposed by Wei$\ss$ (2009b) for time series of binomial counts. Our method extends to binomial AR(p) models a recent result by Jung and Tremayne (2006) for integer-valued autoregressive model of second order, INAR(2), with simple Poisson innovations. Forecasts are produced by conditional median which gives 'coherent' forecasts, and we estimate the forecast distributions of future values of binomial AR(p) models by means of a Monte Carlo method allowing for parameter uncertainty. Model parameters are estimated by the method of moments and estimated standard errors are calculated by means of block of block bootstrap. The method is fitted to log data set used in Wei$\ss$ (2009b).

A Comparison of Technological Growth Models

  • Oh, Hyun-Seung;Moon, Gee-Ju
    • Journal of Korean Society for Quality Management
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    • v.22 no.2
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    • pp.51-68
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    • 1994
  • Various growth models were each fitted onto the data sets in an attempt to determine which growth models achieved the best forecasts for differing types of growth data. Of six such models studied, some models do significantly better than others in predicting future levels of growth. It is recommened that Weibull and the Gompertz growth curve be considered along with Pearl model by those industries presently considering the implementation of substitution analysis in their life analysis. In the early stage of growth, linear estimation should suffice to give reasonable forecasts. In the latter stage, however, as more data become availavle, nonlinear estimation should be used.

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TRAFFIC-FLOW-PREDICTION SYSTEMS BASED ON UPSTREAM TRAFFIC (교통량예측모형의 개발과 평가)

  • 김창균
    • Proceedings of the KOR-KST Conference
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    • 1995.02a
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    • pp.84-98
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    • 1995
  • Network-based model were developed to predict short term future traffic volume based on current traffic, historical average, and upstream traffic. It is presumed that upstream traffic volume can be used to predict the downstream traffic in a specific time period. Three models were developed for traffic flow prediction; a combination of historical average and upstream traffic, a combination of current traffic and upstream traffic, and a combination of all three variables. The three models were evaluated using regression analysis. The third model is found to provide the best prediction for the analyzed data. In order to balance the variables appropriately according to the present traffic condition, a heuristic adaptive weighting system is devised based on the relationships between the beginning period of prediction and the previous periods. The developed models were applied to 15-minute freeway data obtained by regular induction loop detectors. The prediction models were shown to be capable of producing reliable and accurate forecasts under congested traffic condition. The prediction systems perform better in the 15-minute range than in the ranges of 30-to 45-minute. It is also found that the combined models usually produce more consistent forecasts than the historical average.

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