• Asia-Pacific Journal of Atmospheric Sciences
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• v.54 no.4
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• pp.611-622
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• 2018

Observed climate data are processed under the assumption that their time series are stationary, as in multi-step temperature and precipitation prediction, which usually leads to low prediction accuracy. If a climate system model is based on a single prediction model, the prediction results contain significant uncertainty. In order to overcome this drawback, this study uses a method that integrates ensemble prediction and a stepwise regression model based on a mean-valued generation function. In addition, it utilizes empirical mode decomposition (EMD), which is a new method of handling time series. First, a non-stationary time series is decomposed into a series of intrinsic mode functions (IMFs), which are stationary and multi-scale. Then, a different prediction model is constructed for each component of the IMF using numerical ensemble prediction combined with stepwise regression analysis. Finally, the results are fit to a linear regression model, and a short-term climate prediction system is established using the Visual Studio development platform. The model is validated using temperature data from February 1957 to 2005 from 88 weather stations in Guangxi, China. The results show that compared to single-model prediction methods, the EMD and ensemble prediction model is more effective for forecasting climate change and abrupt climate shifts when using historical data for multi-step prediction.

• Journal of Korea Water Resources Association
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• v.31 no.4
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• pp.407-413
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• 1998

This study reviewed the recent studies for the climate change impact on water resource systems and applied one of the techniques to a real reservoir system - the Skagit hydropower system in U.S.A. The technique assumed that the climate change results in ±5% change in monthly average and/or standard deviation of the observed inflows for the Skagit system. For each case of the altered average and standard deviation, an optimal operating policy was derived using s SDP(Stochastic Dynamic Programming) model and compared with the operating policy for the non-climate change case. The results showed that the oparating policy of the Skagit system is more sensitive to the change in the streamflow average than that in the streamflow standard deviation. The derived operating policies were also simulated using the synthetic streamflow scenarios and their average annual gains were compared as a performance index. To choose the best operating policy among the derived policies, a Bayesian decision strategy was also presented with an example. Keywords : climate change, reservoir operating policy, stochastic dynamic programming, Bayesian decision theory.

• Atmosphere
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• v.31 no.3
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• pp.327-340
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• 2021

In this study, the impact of soil moisture initialization in GloSea5, the operational climate prediction system of the Korea Meteorological Administration (KMA), has been investigated for the period of 1991~2010. To overcome the large uncertainties of soil moisture in the reanalysis, JRA55 reanalysis and CMAP precipitation were used as input of JULES land surface model and produced soil moisture initial field. Overall, both mean and variability were initialized drier and smaller than before, and the changes in the surface temperature and pressure in boreal summer and winter were examined using ensemble prediction data. More realistic soil moisture had a significant impact, especially within 2 months. The decreasing (increasing) soil moisture induced increases (decreases) of temperature and decreases (increases) of sea-level pressure in boreal summer and its impacts were maintained for 3~4 months. During the boreal winter, its effect was less significant than in boreal summer and maintained for about 2 months. On the other hand, the changes of surface temperature were more noticeable in the southern hemisphere, and the relationship between temperature and soil moisture was the same as the boreal summer. It has been noted that the impact of land initialization is more evident in the summer hemispheres, and this is expected to improve the simulation of summer heat wave in the KMA's operational climate prediction system.

• Journal of Climate Change Research
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• v.9 no.4
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• pp.435-443
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• 2018

Climate technology applied to address climate change requires a comprehensive review such as environmental and social acceptability in addition to economic feasibility. Not only mitigation and adaptation technologies, but also integration of climate technologies into a business model with other relevant technologies including ICT, finance, and policy instruments could enhance technical, economic, and environmental performances to respond to climate changes. However, many climate projects (and business models) are currently not designed to consider adequately complex climate?related issues. In addition, there is a lack of research on assessment systems that can comprehensively evaluate business feasibility of such models. In this study, we developed a system consisting of nine major indicators in four fields to assess climate technology-based business models. Each indicator was weighed using the analytic hierarchy process (AHP) for systematic assessment of business models. The process can be utilized as a tool to guide improvement of climate technology business models.

• Research in Community and Public Health Nursing
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• v.33 no.4
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• pp.432-445
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• 2022

Purpose: The purpose of this study was to identify the relationship of the school organizational climate with perceived discrimination and the workplace violence among school health teachers. Methods: The research design was a cross-sectional study. The subjects of the study were 350 school health teachers with more than one year of teaching experience. Data were collected online using a questionnaire. Research variables are general characteristics, organizational climate, perceived discrimination, and workplace violence. The relationship between organizational climate and perceived discrimination and the relationship between organizational climate and workplace violence were analyzed using regression analysis. Results: The score for organizational climate of health teachers was 3.10 out of 5 points, the score for perceived discrimination was 2.85 out of 5 points, and the experience rate of workplace violence was 16.9%. School organizational climate was related to both workplace violence and perceived discrimination. The subcomponents of organizational climate affecting perceived discrimination of health teachers were interrelationship and the level of compensation. The subcomponents of organizational climate affecting workplace violence of health teachers were interrelationship and autonomy. Conclusion: The improvement of the school's organizational climate can reduce the level of workplace violence and discrimination against health teachers. It is important to establish an appropriate evaluation system for health teachers and to recognize the role and expertise of health teachers. In addition, it is necessary for school administraters to actively support health teahcers and to create an organizational climate where they can be friendly and communicative.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.58
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• pp.329-351
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• 2013

Since the Kyoto Protocol was released in 2005, there has been a number of mechanisms about funding and how to allocate the burdens. The UNFCCC(United Nations Framework Convention on Climate Change)have discussed establishing an international fund to support the reduction of a greenhouse gas. As the availability of adaption finance for developing countries increase, it's needed for a way of prioritizing countries. This article analyzes the carbon reduction system that includes a emission trading scheme, a carbon tax and examines GCF(Green Climate Fund)'s role and needs. A solution to finance Green Climate Fund is more preferred a harmonized carbon tax that across all nations with carbon tax. Especially the role of industrialized countries is important that based on their historical responsibility for fossil fuel emission. That is, they should get more shares of the global costs than developing countries.

• Atmosphere
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• v.16 no.2
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• pp.141-157
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• 2006

A revolution in weather and climate forecasting is in progress. This has been made possible as a result of theoretical advances in our understanding of the predictability of weather and climate, and by the extraordinary developments in supercomputer technology. New problem areas have been discovered and different solutions have been found by the recent high performance computers whose performance has been increased rapidly. Such advances in the computational performance may change the strategy of development of numerical models and prediction methods. This paper discusses a brief history and current status of the supercomputers in institutions for research and forecast of weather/climate. The main purpose of this study is to provide the preliminary information about supercomputers such as architecture of system and processor. Such information would be useful for meteorologists to understand the features and the preference of supercomputers in each institution.

• Journal of Climate Change Research
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• v.6 no.3
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• pp.203-208
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• 2015

This study was conducted to provide the agricultural climatological basic data for the reset of sowing period of the winter crop on the double cropping system with rice. During the past 30 years from 1981 to 2010, mean air temperature has risen by $0.45^{\circ}C$ per 10 years (with statistical significance), while precipitation has decreased by 6.74 mm per 10 years and the numbers of days for precipitation has reduced by 0.23 days per 10 years (with no statistical significance) in the sowing period ($1^{st}$ Oct. to $5^{th}$ Nov.) of winter crop. It was analyzed that double cropping system of rice and winter crops need to be reset in the way of delaying the sowing time of winter crops, because rising trend of temperature was clear while variability of precipitation was great and the trend was not clear in the sowing period of winter crops. We have also analyzed the meteorological features of the sowing period of winter crops in 2014, and found that mean air temperature in 2014 was higher than that in normal years (similar to recent temperature change feature) while precipitation in 2014 was much more frequent than that in normal years (unlike recent precipitation features). Such tendency in 2014 made the sowing of winter crops difficult because mechanical sowing could not be worked in flooded paddy fields. Heavy rain in October 2014 was also analyzed as a rare phenomenon.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.9-14
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• 2006

This study presented the feasibility of R152a refrigerant as an alternative of R134a which is used in the current automobile air conditioning system. The performance of air conditioning system installed in the actual vehicle was tested using the climate wind tunnel. The experiments were conducted at various refrigerant charge quantities and various driving conditions such as city traffic, highway traffic and parking. Same components and lubricant were used for both R134a and R152a system. The effects of air set values of thermal expansion valve on the performance were also investigated. In case of the R152a system, refrigerant charge quantity can be reduced about 20%, better performance and superior compressor durability is expected due to the lower discharge pressure compared to the R134a system.

• Proceedings of the KSR Conference
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• 2006.11b
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• pp.130-137
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• 2006

In these days abnormal climate occurs frequently because of global warming and earthshock. So it is necessary to prepare for the abnormal conditions like gale, rainfall, heavy snow and high temperature. Fortunately, Korea high speed rail(KTX) have a safety climate detection system for the abnormal weather by using CTC. So the safety is guaranteed in most aspect. But in convention line there isn't any alarm system for the abnormal condition and the train runs until the railroad loss occurred. So convention line need additional regulation same as KTX for the abnormal climate and in the near future passenger safety must be protected by new alarm system.