• Title/Summary/Keyword: future forecast

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Classification of Weather Patterns in the East Asia Region using the K-means Clustering Analysis (K-평균 군집분석을 이용한 동아시아 지역 날씨유형 분류)

  • Cho, Young-Jun;Lee, Hyeon-Cheol;Lim, Byunghwan;Kim, Seung-Bum
    • Atmosphere
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    • v.29 no.4
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    • pp.451-461
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    • 2019
  • Medium-range forecast is highly dependent on ensemble forecast data. However, operational weather forecasters have not enough time to digest all of detailed features revealed in ensemble forecast data. To utilize the ensemble data effectively in medium-range forecasting, representative weather patterns in East Asia in this study are defined. The k-means clustering analysis is applied for the objectivity of weather patterns. Input data used daily Mean Sea Level Pressure (MSLP) anomaly of the ECMWF ReAnalysis-Interim (ERA-Interim) during 1981~2010 (30 years) provided by the European Centre for Medium-Range Weather Forecasts (ECMWF). Using the Explained Variance (EV), the optimal study area is defined by 20~60°N, 100~150°E. The number of clusters defined by Explained Cluster Variance (ECV) is thirty (k = 30). 30 representative weather patterns with their frequencies are summarized. Weather pattern #1 occurred all seasons, but it was about 56% in summer (June~September). The relatively rare occurrence of weather pattern (#30) occurred mainly in winter. Additionally, we investigate the relationship between weather patterns and extreme weather events such as heat wave, cold wave, and heavy rainfall as well as snowfall. The weather patterns associated with heavy rainfall exceeding 110 mm day-1 were #1, #4, and #9 with days (%) of more than 10%. Heavy snowfall events exceeding 24 cm day-1 mainly occurred in weather pattern #28 (4%) and #29 (6%). High and low temperature events (> 34℃ and < -14℃) were associated with weather pattern #1~4 (14~18%) and #28~29 (27~29%), respectively. These results suggest that the classification of various weather patterns will be used as a reference for grouping all ensemble forecast data, which will be useful for the scenario-based medium-range ensemble forecast in the future.

Trend of Population Change and Future Population in Korea - Korean Future in Year 2000; Long Term National Development - (인구변동 추이와 전망 -2000년대를 향한 국가장기발전 구상을 중심으로-)

  • 고갑석
    • Korea journal of population studies
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    • v.8 no.1
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    • pp.87-117
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    • 1985
  • In Principle, the distriction should be understood between projections and forecasts. When the author or user of a projection is willing to describe it as indicating the most likely population at a give date, then he has made a forecast Population change since 1 960 has been reviewed briefly in order to forecast the population of Korea in the year 2,000 which is a leading factor in long term national development plan for which Korea Institute for Population and Health (KIPH) has been participated since 1983. The author of this paper introduced the population forecast prepared for the long term national development plan and an attempt of comparisons with other forecasts such as D.P. Smith's, T. Frejka's, Economic Planning Board's (EPB), UN's and S.B. Lee's was made. Those six forecasts of Korean future population in year 2,000 varried from 48.5 million to 50.0 million due to the base population and assumption of fertility and mortality however the range of total population size is not large enough. Taking four forecasts such as KIPH, EPB, UN, and Lee based on 1980 population census results and latest data of fertility and mortality, KIPH and UN forecast are close in total population size even though there was a slight difference in fertility and mortality assumptions. The smallest size of total population was shown by S.B. Lee (see Table 13) although the difference between KIPH and Lee was approximately one million which is two percent of total population in year 2,000. As a summary of conclusion the author pointed out that one can take anyone of forecasts prepared by different body because size and proportion wise of the Korean population until early I 990s can not be different much and new population projections must be provided by using 1985 population census data and other latest fertility and mortality information coflected by Korea Institute for Population and Health and Economic Planning Board in forth comming year.

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The Effect of Management Forecast Precision on CEO Compensation -Focusing on Bad news Firm- (악재를 경험한 기업의 경영자 이익예측 정확성이 경영자 보상에 미치는 영향)

  • Lee, Eun-Ju;Kim, Ha-Eun
    • Journal of Digital Convergence
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    • v.17 no.4
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    • pp.107-114
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    • 2019
  • This study analyzes the effect of the accuracy of future management performance, which managers voluntarily announce in the previous year's disclosure, on managers compensation. In the case of a company that disclosed the bad news in the previous year, the ability to predict uncertain future will be more important, and expects executives with better predictability to receive more compensation. The results of this study show that there is a significant negative(-) relationship between the accuracy of the manager's earnings forecast and the performance - compensation of the firms that disclosed the bad news in the previous year. The accuracy of the manager's disclosure is important, and it is confirmed that the manager's compensation increases as the incentive of the manager's effort to reduce future uncertainty. The results of this study are as follows: there is a positive relationship between the managerial performance and the managerial competence of managers. It is important to note that there is a difference and that we have identified additional determinants of the manager compensation contract.

A Study on Trend Impact Analysis Based of Adaptive Neuro-Fuzzy Inference System

  • Yong-Gil Kim;Kang-Yeon Lee
    • International journal of advanced smart convergence
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    • v.12 no.1
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    • pp.199-207
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    • 2023
  • Trend Impact Analysis is a prominent hybrid method has been used in future studies with a modified surprise- free forecast. It considers experts' perceptions about how future events may change the surprise-free forecast. It is an advanced forecasting tool used in futures studies for identifying, understanding and analyzing the consequences of unprecedented events on future trends. In this paper, we propose an advanced mechanism to generate more justifiable estimates to the probability of occurrence of an unprecedented event as a function of time with different degrees of severity using adaptive neuro-fuzzy inference system (ANFIS). The key idea of the paper is to enhance the generic process of reasoning with fuzzy logic and neural network by adding the additional step of attributes simulation, as unprecedented events do not occur all of a sudden but rather their occurrence is affected by change in the values of a set of attributes. An ANFIS approach is used to identify the occurrence and severity of an event, depending on the values of its trigger attributes.

Numerical Weather Prediction and Forecast Application (수치모델링과 예보)

  • Woo-Jin Lee;Rae-Seol Park;In-Hyuk Kwon;Junghan Kim
    • Atmosphere
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    • v.33 no.2
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    • pp.73-104
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    • 2023
  • Over the past 60 years, Korean numerical weather prediction (NWP) has advanced rapidly with the collaborative effort between the science community and the operational modelling center. With an improved scientific understanding and the growth of information technology infrastructure, Korea is able to provide reliable and seamless weather forecast service, which can predict beyond a 10 days period. The application of NWP has expanded to support decision making in weather-sensitive sectors of society, exploiting both storm-scale high-impact weather forecasts in a very short range, and sub-seasonal climate predictions in an extended range. This article gives an approximate chronological account of the NWP over three periods separated by breakpoints in 1990 and 2005, in terms of dynamical core, physics, data assimilation, operational system, and forecast application. Challenges for future development of NWP are briefly discussed.

The Simulation and Forecast Model for Human Resources of Semiconductor Wafer Fab Operation

  • Tzeng, Gwo-Hshiung;Chang, Chun-Yen;Lo, Mei-Chen
    • Industrial Engineering and Management Systems
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    • v.4 no.1
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    • pp.47-53
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    • 2005
  • The efficiency of fabrication (fab) operation is one of the key factors in order for a semiconductor manufacturing company to stay competitive. Optimization of manpower and forecasting manpower needs in a modern fab is an essential part of the future strategic planing and a very important to the operational efficiency. As the semiconductor manufacturing technology has entered the 8-inch wafer era, the complexity of fab operation increases with the increase of wafer size. The wafer handling method has evolved from manual mode in 6-inch wafer fab to semi-automated or fully automated factory in 8-inch and 12-inch wafer fab. The distribution of manpower requirement in each specialty varied as the trend of fab operation goes for downsizing manpower with automation and outsourcing maintenance work. This paper is to study the specialty distribution of manpower from the requirement in a typical 6-inch, 8-inch to 12-inch wafer fab. The human resource planning in today’s fab operation shall consider many factors, which include the stability of technical talents. This empirical study mainly focuses on the human resource planning, the manpower distribution of specialty structure and the forecast model of internal demand/supply in current semiconductor manufacturing company. Considering the market fluctuation with the demand of varied products and the advance in process technology, the study is to design a headcount forecast model based on current manpower planning for direct labour (DL) and indirect labour (IDL) in Taiwan’s fab. The model can be used to forecast the future manpower requirement on each specialty for the strategic planning of human resource to serve the development of the industry.

A study on factors influencing the change of children's psycho-social development raised by disabled parents: focused on the influence of parent's social engagement and future forecast (장애부모에게서 자란 아동의 심리사회성 변화요인 - 부모의 사회참여활동 및 미래전망을 중심으로 -)

  • Kim, Sa Hyun;Kim, So Jin
    • Korean Journal of Family Social Work
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    • no.53
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    • pp.199-234
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    • 2016
  • This study deals with the psycho-social development of children raised by disabled parents. In particular, we are willing to examine the influence of parental factors such as social engagement and future forecast on the change of children's psycho-social development. Using the three waves of Korean Welfare Panel Study data, these predictors were examined through the Latent Growth Curve Modeling. The result shows that parent's disability has a negative influence on their children's psycho-social development. However, similar to the findings of the previous studies, the degree of this influence tends to be decreased as children grow up. Lastly, two parental factors have a direct influence on the psychological development of children. Furthermore, parent's social engagement has an indirect influence on the change of sociality of children through the psychological change of them. This result means that we should encourage disabled parents to participate actively in social activities and think positively about their future.