• The Korean Journal of Quaternary Research
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• v.21 no.2
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• pp.39-40
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• 2007

• Proceedings of the KGS Conference
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• 2005.05a
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• pp.76-77
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• 2005

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.2
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• pp.1-13
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• 2015

The Coupled Model Intercomparison Project Phase 5 (CMIP5), coordinated by the World Climate Research Programme in support of the Intergovernmental Panel on Climate Change (IPCC) AR5, is the most recent, provides projections of future climate change using various global climate models under four major greenhouse gas emission scenarios. There is a wide selection of climate models available to provide projections of future climate change. These provide for a wide range of possible outcomes when trying to inform managers about possible climate changes. Hence, future agrometeorological indicators estimation will be much impacted by which global climate model and climate change scenarios are used. Decision makers are increasingly expected to use climate information, but the uncertainties associated with global climate models pose substantial hurdles for agricultural resources planning. Although it is the most reasonable that quantifying of the future uncertainty using climate change scenarios, preliminary analysis using reasonable factors for selecting a subset for decision making are needed. In order to narrow the projections to a handful of models that could be used in a climate change impact study, we could provide effective information for selecting climate model and scenarios for climate change impact assessment using maximum/minimum temperature, precipitation, reference evapotranspiration, and moisture index of nine Representative Concentration Pathways (RCP) scenarios.

• The Journal of Industrial Distribution & Business
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• v.11 no.3
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• pp.39-50
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• 2020

Purpose: Agriculture, which is heavily influenced by climate conditions, is one of the industries most affected by climate change. In this respect, various studies on the impact of climate change on the agricultural market have been conducted. Since climate change is a long-term phenomenon for more than a decade, long-term projections of agricultural prices as well as climate variables are needed to properly analyze the impact of climate change on the agricultural market. However, these long-term price projections are often major constraints on studies of climate changes. The purpose of this study is to analyze the impacts of climate changes on the Korean onion market using ex-post analysis approach in order to avoid the difficulties of long-term price projections. Research design, data and methodology: This study develops an annual dynamic partial equilibrium model of Korean onion market. The behavioral equations of the model were estimated by OLS based on the annual data from 1988 to 2018. The modelling system is first simulated to have actual onion market conditions from 2014 to 2018 as a baseline and then compared it to the scenario assuming the climatic conditions under RCP8.5 over the same period. Scenario analyses were simulated by both comparative static and dynamic approach to evaluate the differences between the two approaches. Results: According to the empirical results, if the climate conditions under RCP8.5 were applied from 2014 to 2018, the yield of onion would increase by about 4%, and the price of onion would decrease from 3.7% to 17.4%. In addition, the average price fluctuation rate over the five years under RCP8.5 climate conditions is 56%, which is more volatile than 46% under actual climate conditions. Empirical results also show that the price decreases have been alleviated in dynamic model compared with comparative static model. Conclusions: Empirical results show that climate change is expected to increase onion yields and reduce onion prices. Therefore, the appropriate countermeasures against climate change in Korean onion market should be found in the stabilization of supply and demand for price stabilization rather than technical aspects such as the development of new varieties to increase productivity.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.3
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• pp.37-45
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• 2008

Quality assessment ai s to evaluate if a distorted image or video has a good quality by measuring the difference between the original and distorted images or videos. In this paper, to assess the visual qualify of a distorted image or video, visual features of the distorted image are compared with those of the original image instead of the direct comparison of the distorted image with the original image. We use edge projections from two images as features, where the edge projection can be easily obtained by projecting edge pixels in an edge map along vertical/horizontal direction. In this paper, edge projections are obtained by using vertical/horizontal directions of gradients as well as the magnitude of each gradient. Experimental results show the effectiveness of the proposed quality assessment through the comparison with conventional quality assessment algorithms such as structural similarity(SSIM), edge peak signal-to-noise ratio(EPSNR), and edge histogram descriptor(EHD) methods.

• Journal of the Institute of Convergence Signal Processing
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• v.7 no.4
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• pp.169-177
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• 2006

In this paper, we present an efficient image reconstruction method which is suited to remove various noise generated from measurement using X-ray attenuation. To be specific, we present a wavelet method to efficiently remove ring artifacts, which are caused by inevitable mechanical error in X-ray emitters and detectors. and streak artifacts, which are caused by general observation errors and Fourier transform-based reconstruction process. To remove ring artifacts related noise from projections, we suggest to estimate the noise intensity by using the fact that the noise related to ring artifacts has a strong correlation in the angle direction, and remove them by using wavelet shrinkage. We also suggest to use wavelet-vaguelette decomposition for general-purpose noise removal and image reconstruction. Through simulation studies. we show that the proposed method provides a better result in ring artifact removal and image reconstruction over the traditional Fourier transform-based methods.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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• pp.154-154
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• 2018

To interpret the climate projections for the future as well as present, recognition of the consequences of the climate internal variability and quantification its uncertainty play a vital role. The Korean Peninsula belongs to the Far East Asian Monsoon region and its rainfall characteristics are very complex from time and space perspective. Its internal variability is expected to be large, but this variability has not been completely investigated to date especially using models of high temporal resolutions. Due to coarse spatial and temporal resolutions of General Circulation Models (GCM) projections, several studies adopted dynamic and statistical downscaling approaches to infer meterological forcing from climate change projections at local spatial scales and fine temporal resolutions. In this study, stochastic downscaling methodology was adopted to downscale daily GCM resolutions to hourly time scale using an hourly weather generator, the Advanced WEather GENerator (AWE-GEN). After extracting factors of change from the GCM realizations, these were applied to the climatic statistics inferred from historical observations to re-evaluate parameters of the weather generator. The re-parameterized generator yields hourly time series which can be considered to be representative of future climate conditions. Further, 30 ensemble members of hourly precipitation were generated for each selected station to quantify uncertainty. Spatial map was generated to visualize as separated zones formed through K-means cluster algorithm which region is more inconsistent as compared to the climatological norm or in which region the probability of occurrence of the extremes event is high. The results showed that the stations located near the coastal regions are more uncertain as compared to inland regions. Such information will be ultimately helpful for planning future adaptation and mitigation measures against extreme events.

• The Journal of Korean Academy of Prosthodontics
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• v.36 no.6
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• pp.900-913
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• 1998

Despite of technical difficulties, the combination of occlusal projection and densitometric digital analysis may ultimately provide a means of detection of subtle bone loss at the facial and lingual side of dental implant (Oblique occlusal view is more useful for $ITI^{(R)}$ dental implant due to its contour of shoulder as like tulip flower). In this study, conventional periapical projections of x-ray beam had shown more high sensitivity to detect the bony defects than oblique occlusal projections in alveolar crest obscured by dental implants or not, even if the difference was not statistically significant. Unlike conventional periapical projections. occusal projections combined with densitometric digital analysis technique may provide a means for detection of subtle bone change at the all around of implants without obscuring effect by implant itself. Although the results from this in vitro study were performed under limited circumstances, these results might afford more possibility and versatile modality of diagnosis options to clinician in the implant practice.

• Journal of the Korean Data and Information Science Society
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• v.28 no.1
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• pp.99-108
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• 2017

There are three official official demographics of the Republic of Korea: the population census, population projections, and resident population. Among these, the population projections estimates are based on population census statistics, which are conducted every five years. This study compared and analyzed the future population statistics and resident population statistics. In order to detect errors in the census process, we surveyed the outliers of demographic data. Based on these, we aimed to verify the reliability of official demographics. Resident registration demographics showed a tendency to increase as the age increased from 0 to 12 years, although the population had to decrease as the age increased. In the population projections, as the age increases from 18 to 28, a new population has developed and the population has increased. Also, in the resident population, between 2009 and 2010, in the population projections, between 2010 and 2011, there was a strange phenomenon that the population grew as a result of a new population as the age of all ages increased. Both official demographics need to be carried out through more accurate verification. Increasing the reliability of the aged population survey on the elderly population statistics will provide greater efficiency in establishing administrative policies.

• Journal of Periodontal and Implant Science
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• v.16 no.1
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• pp.96.2-96.2
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• 1986