• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.4
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• pp.464-473
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• 2016

The air temperatures of the coast and inland are rising due to an increase in carbon dioxide emissions and abnormal climate phenomena caused by global warming, El Nino, La Nina and so on. The sea levels of the Earth are rising by approximately 2.0 mm per year (global average value) due to the thermal expansion of sea water, melting of glaciers and other causes by global warming. On the other hand, when it comes to designing a hydraulic structure or coastal hydraulic structure, the standard of the design water level is decided by analyzing four largeness tide values and a harmonic constant with the observed tidal water level or simulating numerical model. Therefore, the design tidal water level needs to consider an increasing speed of the seawater level, which corresponds to the design frequency. In the present study, the observed tidal water levels targeting 46 tidal stations operated by the Korea Hydrographic and Oceanographic Administration (KHOA) from the beginning of observations to 2015 per hour were collected. The variation of the monthly and yearly and increasing ratio were performed and divided into 7 seas, such as east and west part of the Southern Sea, south part and middle of the East Sea, south part and middle of the Western Sea, and Jeju Sea. The current study could be used to determine the cause of local seawater rises and reflect the design tidal water level as basic data.

• Journal of Environmental Impact Assessment
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• v.24 no.2
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• pp.190-203
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• 2015

VRI(Vulnerability-Resilience Index), which is defined as a function of 3 variables: climate exposure, sensitivity, and adaptive capacity, has been quantified for the case of Typhoon which is one of the extreme weathers that will become more serious as climate change proceeds. Because VRI is only indicating the relative importance of vulnerability between regions, the VRI quantification is prerequisite for the effective adaptation policy for climate in Korea. For this purpose, damage statistics such as amount of damage, occurrence frequency, and major damaged districts caused by Typhoon over the past 20 years, has been employed. According to the VRI definition, we first calculated VRI over every district in the case of both with and without weighting factors of climate exposure proxy variables. For the quantitative estimation of weighting factors, we calculated correlation coefficients (R) for each of the proxy variables against damage statistics of Typhoon, and then used R as weighting factors of proxy variables. The results without applying weighting factors indicates some biases between VRI and damage statistics in some regions, but most of biases has been improved by applying weighting factors. Finally, due to the relations between VRI and damage statistics, we are able to quantify VRI expressed as a unit of KRW, showing that VRI=1 is approximately corresponding to 500 hundred million KRW. This methodology of VRI quantification employed in this study, can be also practically applied to the number of future climate scenario studies over Korea.

• Journal of Korea Water Resources Association
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• v.48 no.4
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• pp.245-255
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• 2015

This study used high density network of integrated meteorological sensor, which are operated by SK Planet, with KMA weather stations to estimate the quantitative precipitation field in Seoul area. We introduced SK Planet network and analyzed quality of the observed data for 3 months data from 1 July to 30 September 2013. As the quality analysis result, we checked most SK Planet stations observed similar with previous KMA stations. We developed the real-time quality check and adjustment method to reduce the error effect for hydrological application by missing and outlier value and we confirmed the developed method can be corrected the missing and outlier value. Through this method, we used the 190 stations(KMA 34 stations, SK Planet 156 stations) that missing ratio is less than 20% and the effect of the outlier was the smallest for quantitative precipitation estimation. Moreover, we evaluated reproducibility of rainfall field high density rain gauge network has $3km^2$/gauge. As the result, the spatial relative frequency of rainfall field using SK Planet and KMA stations is similar with radar rainfall field. And, it supplement the blank of KMA observation network. Especially, through this research we will take advantage of the density of the network to estimate rainfall field which can be considered as a very good approximation of the true value.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.155-160
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• 2012

This study was conducted to develop a practical method for estimating the extremes of minimum air temperature with given return-period based on the frequency distribution of daily minimum air temperature in January. Daily temperature data were collected from 61 meteorological observatories country-wide from 1961 to 2010. Most of daily minimum temperature in January could be represented by a normal-distribution, so it is possible to predict stochastically the lowest temperature by the mean and standard deviation. We developed a quadratic function to estimate standard deviation in terms of daily minimum temperature in January. Also, we introduced a coefficient which can be used to predict an extreme of minimum temperature with mean and standard deviation, and is dependent on return-periods. Using this method, we were able to reproduce the past 30-year extremes with an error of 1.1 on average and 5.3 in the worst case.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.4
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• pp.346-358
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• 2016

Local food reflects the identity and image of a specific region. It is also a core element for determining tourists' experience of a region. The purpose of the present study was to develop a Jeju food tour package using local foods and estimate the economic value of the suggested tour package using Contingent Valuation Method (CVM). Five food tour packages were developed by researchers. In order to modify and measure the value of each package, an expert panel survey was conducted, and 'package 5' was selected as a food tour scenario for the tourist survey. A survey was conducted on 295 domestic tourists who visited Jeju within the past 10 years in order to evaluate the economic value and feasibility of the Jeju food tour package. A total fo 72.9% of respondents answered that they were willing to pay for the Jeju local food tour, and the willingness to pay (WTP) range was between ￦45,000 and ￦105,000. The primary factors correlated with WTP was food expenses, followed by leisure experience expenses, interest in local foods, education level, visit frequency and age. The WTP of the Jeju local food tour was calculated with the significantly affected factors using stepwise regression model. The result of the present study reveal that tourists' WTP increased with higher food expenses, education level, and age group. The average value of food expenses, education level, and age were substituted into the formula derived from the regression analysis, yielding 58,385.752 KRW as the WTP. The expected economic value created by exploiting the Jeju local food tour was shown to be 700 billion KRW per year, calculated by multiplying WTP of the food tour packages by the number of tourists. This study examined the feasibility and plan of the food tour package to increase the economic value of Jeju local food. In the case of the culinary tour program based on Jeju local food launching, the estimated economic effect was great. Therefore, in-depth research to merchandise the Jeju local food tour program is needed.

• Korean journal of applied entomology
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• v.51 no.4
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• pp.479-484
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• 2012

The occurrence of plum fruit moth, Grapholita dimorpha, has been recently reported in apple orchards in Korea. It has been suspected that G. dimorpha and its related species, G. molesta, may occur simultaneously in other host plants. This study reports the occurrence of G. dimorpha in pear orchards of different localities in Korea. The identification of G. dimorpha was determined by morphological characters and the DNA marker. The cross-trapping of both species may be possible because the major sex pheromone (SP) compositions for the two species are similar. From the monitoring data, G. dimorpha and G. molesta were caught in SP lure traps of G. dimorpha and both species were also caught in SP lure traps of G. molesta. This cross-trapping of G. molesta to a SP lure of G. dimorpha varied significantly among pear orchards in different geographical localities. Furthermore, the occurrence peaks of the two species were not coincidental in all monitored orchards. These suggest that monitoring data obtained from each SP trap of both species in pear orchards may be mixed with two species, which would result in the over-estimation of population density and peak frequency on both species in pear orchards.

• Geophysics and Geophysical Exploration
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• v.5 no.4
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• pp.309-315
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• 2002

Conventional electromagnetic (EM) method using small loops as a source and receiver has been used in detection of conductive buried objects like a metal detector or in qualitative estimation of the subsurface conductivity variation. Recently, however, since detection of buried objects and imaging of the subsurface conductivity distribution in a relatively conductive area are in a high demand for environmental and engineering purposes, the quantitative interpretation technique of EM data is actively studied. In this regard, we introduce a brief principle of EM survey and show an example of the detection of buried conductive material and imaging of the subsurface conductivity distribution based on data measured at a test survey area. Through this study, we show that multi-frequency EM surveys using small loops may be a good solution to give quick and detail information of subsurface in a conductive survey area.

• Journal of the Korea Convergence Society
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• v.8 no.6
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• pp.29-36
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• 2017

In this paper, we propose a method for generating improved saliency map by learning multiple features to improve the accuracy and reliability of saliency map which has similar result to human visual perception type. In order to overcome the inaccurate result of reverse selection or partial loss in color based salient area estimation in existing salience map generation, the proposed method generates multi feature data based on learning. The features to be considered in the image are analyzed through the process of distinguishing the color pattern and the region having the specificity in the original image, and the learning data is composed by the combination of the similar protrusion area definition and the specificity area using the LAB color space based color analysis. After combining the training data with the extrinsic information obtained from low level features such as frequency, color, and focus information, we reconstructed the final saliency map to minimize the inaccurate saliency area. For the experiment, we compared the ground truth image with the experimental results and obtained the precision-recall value.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.21 no.7
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• pp.796-804
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• 2010

It is important to use the comb type pilot allocation for the continuous channel and efficient processing. And DFT-spreading OFDM is used a lot to solve high PAPR problem of OFDM system. However, PAPR is increased again when comb type pilot is used to estimate channel characteristics. So, in this paper, we employ a new SLM method to DFT-spreading OFDM system to reduce increased high PAPR. And we suggest an effective method to transmit side information without additional bandwidth. Pilot and side information must be preserved from jamming or intentional interferences since those are very important in DFT spread OFDM system using SLM. So, in this paper, we like to analyze and simulate the performance of DFT spread OFDM system based on SLM against jamming signal. To remedy the vulnerable shortcomings of DFT spread OFDM about jamming or intentional interferences, we employ FH(Frequency Hopping) method and analyze system performance under the several jamming conditions such as MTJ(Multi Tone Jamming) and PBJ(Partial Band Jamming).

• Journal of the Korean Institute of Landscape Architecture
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• v.41 no.4
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• pp.77-84
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• 2013

With the increase in occurrence frequency and severity of natural disasters due to climate changes arising from global warming, damage in the landscaping field is rising. This leads to legal disputes, and is increasing social and economic damage, too. Especially even though landscape trees which are highly affected by external environments, suffer lots of damage from natural disasters, there is no specific scope of disaster criteria and thus it brings plenty of problems of damage restoration and compensation. Therefore, this study aims to suggest that gives ways to improve related criteria for damage of landscape trees from natural disasters. For this objective, this study analyzed damage cases of landscape trees and precedents, and compared Korean and Japanese legal systems and criteria regarding natural disasters with each other. The analysis result showed that opinions of experts have a great deal of influence on judgment results, since there is no definite legal basis on damage from natural disasters in the landscaping field. This implies the need for a professional and objective appraisal process. According to the comparative analysis of Korean and Japanese legal systems and criteria regarding natural disasters, Korea lacked in laws and criteria on natural disasters of landscape plants in Korea, whereas there were concrete disaster assessment standards of landscape trees in Japan. For improving natural disaster-related systems and criteria in the landscaping field, therefore, this study presented 'Revision of related laws', 'Revision of appraisal and loss assessment criteria', 'Revision of standard specification of landscaping project', 'Compulsory insuring against disasters', 'Reasonable fulfillment of contract', and 'Compulsory cost estimation for disaster restoration', as improvement plans.