• Journal of the Korea Society for Simulation
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• v.19 no.2
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• pp.119-125
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• 2010

In ad-hoc networks, dynamically reconfigurable and temporary wireless networks, all mobile devices cooperatively maintain network connectivity with no assistance of base stations while they have limited amounts of energy that is used in different rates depending on the power level. Since every node has to perform the functions of a router, if some nodes die early due to lack of energy, it will not be possible for other nodes to communicate with each other and network lifetime will be shortened. Consequently, it is very important to develop a technique to efficiently consume the limited amounts of energy resources so that the network lifetime is maximized. In this paper, geographical localized routing is proposed to help making smarter routing decision using only local information and reduce the routing overhead. The proposed localized routing algorithm selects energy-aware neighbors considering the transmission energy and error rate over the wireless link, and the residual energy of the node, which enables nodes to achieve balanced energy-consumption and the network lifetime to prolong.

• Journal of Korea Water Resources Association
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• v.51 no.3
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• pp.235-246
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• 2018

The main purpose of this study is to suggest a methodology for identifying vulnerable region in Choyang creek basin susceptible to soil losses based on runoff aggregation structure and energy expenditure pattern of natural river basin within the framework of power law distribution. To this end geomorphologic factors of every point in the basin of interest are extracted by using GIS, which define tractive force and stream power as well as drainage area, and then their complementary cumulative distributions are graphically analyzed through fitting them to power law distribution to identify the sensitive points within the basin susceptible to soil losses with respect to scaling regimes of tractive force and stream power. It is observed that the range of vulnerable region by scaling regime of tractive force is much narrower than by scaling regime of stream power. This result seems to be due to the tractive force is a kind of scale dependent factor which does not follow power law distribution and does not adequately reflect energy expenditure pattern of river basins. Therefore, stream power is preferred to be a more reasonable factor for the evaluation of soil losses. The methodology proposed in this study can be validated by visualizing the path of soil losses, which is generated from hill-slope process characterized by local slope, to the valley through fluvial process characterized by drainage area as well as local slope.

• Journal of the Korean Society for Marine Environment & Energy
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• v.8 no.4
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• pp.186-192
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• 2005

We investigated the deposition characteristics and mass transport flux estimation of the Nakdong estuary, Korea. To understand the effects of the tidal current circulation that influences estuary terrain changes, we used a 2D numerical model to map seawater circulation under three different situations, with the level of river flow being set as none or flood. The net-water flux of the cross-sectional area between sandbars (known as dung) was estimated. From our review of previous research, we know that the development of local sandbars shifted from the west to the east side of the estuary after the construction of the Nakdong River dike. Current development is occurring mostly at the Bakhap-dung near Tadea. The seawater circulation pattern over this large-scale area of tidal na is brings changes related to the quantity of the outflow from the Nakdong River. Based on the calculated results for the net-water flux of the cross-sectional area, we see very strong accumulation in local waters around Jangjiado, Bakhapdung, and Tadae under flood river flow conditions, but accumulation in local waters around Jinudo under the other states of flow. Consequently, in the Nakdong estuary, the main sensitive regions that are affected by changes in the flow of river discharge are the local waters around Jangiado, Bakhapdung, Tadae, and Jinudo.

• Journal of Climate Change Research
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• v.5 no.2
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• pp.165-178
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• 2014

National and local governmental adaptation plan for climate change will become mandatory in 2015. In order to establish the plan, assessment of vulnerability to climate change needs to be preceded. LCCGIS, a toolkit for vulnerability assessment, has been widely used by many local governments. However, assessment results by LCCGIS are not yet reliable because most of the vulnerability indices applied to LCCGIS　have the same value for almost all administrative units in Korea. In this study, proxy variables for hard-collectable indices were introduced, and the results were compared with those without any proxy variables. Vulnerability assessment could be conducted subjectively due to uncertainty. Thus, determination of objective indices, understanding the available data, and changes of indices in local conditions were organized. Results from this study are expected to make vulnerability assessment reliable and contribute to assessing vulnerability to climate change reflecting on local governmental characteristics.

• Korean Journal of Community Nutrition
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• v.6 no.2
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• pp.205-217
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• 2001

This survey was carried out to study the difference of nutrient intake, food behavior and health condition according to food intake diversity in the elderly(age 65 year over and 74 year under) in a local city. A diet survey with one day 24-recall method was used for 216 subjects(65 male & 151 female). Based on a food intake diversity examination, including an evaluation of KDDS(Korean's Dietary Diversity Score ; counts the number of food groups consumed daily from total five food groups(cereal, meat, vegetable, dairy, and oil groups)), Meal Balance(apply the KDDS at breakfast, lunch and dinner), and DVS(Dietary Variety Score ; total number of foods consumed), subjects were clustered according to food intake diversity. Food intake diversity patterns of male and female clusters were classified each into threes(Male-low group(24.6%), middle group(33.8%), and high group(41.5%)/Female low group(41.7%) middle group(37.1%), and high group(21.2%). The averages of KDDS, Meal Balance and DVS were 3.0, 7.5, 14.8 in the male middle group, and 4.5, 10.2, 25.7 in the male high group, 2.7, 6.3, 14.3 in the female low group, 4.0, 8.6, 18.0 in the female middle group, and 4.5, 10.5, 25.7 in the female high group respectively. The average dairy intake of nutrients below the RDA were energy, protein, Ca, Fe, Vitamin A, Vitamin B$_2$and niacin in the male low group, energy, protein, Ca, Fe, Vitamin A, Vitamin B$_2$in the male middle group and energy, Ca, Vitamin B$_2$in the male high group but a little. Also the female low group had intakes of all nutrients except Vitamin C, the middle group had intakes of energy, protein, Ca, Fe, Vitamin A, Vitamin B$_2$, and the female high group had intakes of energy, Ca, Vitamin A below the RDA respectively. Food intake diversity increasing, nutrient intake, food behavior and health condition proved to be good. This study explored the usefulness of cluster analysis in identifying food intake diversity of three groups of the elderly in relation to their nutrient intake, food behavior and health conditions.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.3
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• pp.159-165
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• 2005

The characterization of radiological contamination inside pipes generated during the decommission of a nuclear facility is necessary before pipes can be recycled or disposed. But, existing direct measurements of radioactive contamination level using the survey-meter can not estimate the characteristic of contamination on a local area such as the pipe inside. Moreover, the measurement of surface contamination level using the indirect methods has many problems of an application because of the difficulty of collecting sample and contamination possibility of a worker when collecting sample. In this work, plastic scintillator was simulated by using Monte Carlo simulation method for detection of beta radiation emitted from internal surfaces of small diameter pipe. Simulation results predicted the optimum thickness and geometry of plastic scintillator at which energy absorption for beta radiation was maximized. In addition, the problem of scintillator processing and transferring the detector into the pipe inside was considered when fabricating the plastic detector on the basis of simulation results. The characteristic of detector fabricated was also estimated. As a result, it was confirmed that detector capability was suitable for the measurement of contamination level. Also, the development of a detector for estimating the radiological characteristic of contamination on a local area such as the pipe inside was proven to be feasible.

• Journal of Energy Engineering
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• v.23 no.4
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• pp.176-182
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• 2014

The project of promoting the economy has attracted attention as on strategy for the economic revitalization of abandoned mine areas which is promoting by local government based on the "Special law on the development of abandoned mine areas". Through the analysis of economic feasibility analysis, the government is trying to determine the presence or absence of budget support to project of promoting the economy of local government. Furthermore, this paper attempts to conduct a cost-benefit analysis, using net present value(NPV), benefit/cost(B/C) ratio, internal rate of return(IRR) techniques for project of promoting the economy of Samcheok City. The project of promoting the economic of Samcheok City is promoting the Yukbaeksan flowers rest park and Glass Art Culture and Tourism theme park. The results indicate that NPV, B/C ratio and IRR of Yukbaeksan flowers rest park are 3,937 million won, 1.06, 6.18% and NPV, B/C ratio and IRR of Glass Art Culture and Tourism theme park are 8,311 million won, 1.34 and 9.47. Accordingly, the projects of promoting the economic of Samcheok City ensure economic feasibility that the three indicators have exceeded 0, 1.0 and 5.5% respectively. Moreover, the analysis results can be used effectively in the decision for the project of promoting ecomony of Samcheok city.

• International Journal of Highway Engineering
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• v.11 no.1
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• pp.135-144
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• 2009

The purpose of this study is to develop a simple and rational crack evaluation system using Marshall tester. Fracture energy were used as a parameter to evaluate the crack resistance of asphalt mixtures. Marshall tester basically measures the vertical deformation obtained from the linear variable differential transformer(LVDT) attached on the specimen's exterior, which can cause a measurement error due to the local deformation near the loading head. Therefore, the validity of the measurement system of Marshall tester should be tested to use it in calculation of fracture energy. Two types of indirect tensile strength tests were performed using four types of asphalt mixtures at two temperature conditions. From the tests, it was shown that local deformation near the loading head had not occurred before a specimen was fractured, so that it did not cause the measurement error of fracture energy. And also from the statistic analysis, the coefficient of variation of vertical deformation measurements obtained on specimen's exterior is less than 15%. Thus, vertical deformation measurements obtained on the specimen's exterior can be used in crack evaluation system using Marshall tester.

• Journal of the Korean Society for Library and Information Science
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• v.48 no.2
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• pp.259-285
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• 2014

Public policies in regard to developing reading culture programs and the contents, and in running public libraries have been used to overcome existing social issues such as regional self-centeredness and cultural lagging. It means that public libraries are playing an important role to encourage communications within local communities. The purpose of this research is therefore to analyze the concept of local community, and develop reading culture and contents to reinforce the concept. This research also targeted to analyze the required contents in reading culture. Through the case study of "G" city, the research analyzed their citizenship and sense of local community and the requests. As a result, the requited subjects were for economics, unemployment, poverty, aging, and housing order. For the subjects of environment were environment pollution and energy order. For the subjects of human rights, disabilities, and multi-cultural were requested. For the subject of education, school violence, tutoring, and truly teaching were requested. Based on the requirements, 221 items of reading lists, DVD clips, and abstracts are developed as well as 4 programs of reading culture.

• Journal of the Korean Dietetic Association
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• v.8 no.2
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• pp.185-198
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• 2002

The purpose of this study was to compare food habits and nutrient intakes with body mass index of hypertensive patients commuting to a Local Health Center. A total of 85 patients were divided into two groups according to BMI. The non-obese group comprised 43 subjects with BMI below 25㎏/$m^2$ , while the obese group comprised 42 subjects with BMI above 25㎏/$m^2$ . All Subjects were interviewed for general characteristics, food habits, clinical characteristics, effort for health maintenance and the knowledge of hypertension and nutrition. Anthropometric assessments such as weight, height, waist-hip ratio and biochemical measurement of blood urea nitrogen, creatinine, triglyceride, total cholesterol, HDL-cholesterol and fasting blood glucose(FBG) were obtained from subjects. In general characteristics, smoking, drinking, exercise, and hypertension status were not significantly different between the two groups. Food habits and the means of daily energy and nutrients were not significantly different between the two groups. An analysis of the percentage of RDA(Recommended Dietary Allowances of Korea, 2000) consumed by patients showed that but for ascorbic acid and phosphorus, all nutrients were below the RDA. And intakes of vitamin $B_1$(P<0.001), vitamin $B_2$(P<0.01), niacin(P<0.001) of the obese group were significantly lower than that of the non-obese group. Blood urea nitrogen, creatinine, triglyceride, total cholesterol, HDL-cholesterol and fasting blood glucose were in the normal range and there was not a significant difference in the two groups. Therefore, more effective nutrition education programs about exercise, smoking, caloric intake, vitamins and minerals are required for hypertensive patients commuting to Local Health Center.