• Nuclear Engineering and Technology
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• v.55 no.6
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• pp.1966-1973
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• 2023

Virtual reality technology has been widely used in the field of nuclear and radiation safety, dose rate computing in virtual environment is essential for optimizing radiation protection and planning the work in radioactive-controlled area. Because the CPU-based gamma dose rate computing takes up a large amount of time and computing power for voxelization of volumetric radioactive source, it is inefficient and limited in its applied scope. This study is to develop an efficient gamma dose rate computing code and apply into fast virtual simulation. To improve the computing efficiency of the point kernel algorithm in the reference (Li et al., 2020), we design a GPU-based computing framework for taking full advantage of computing power of virtual engine, propose a novel voxelization algorithm of volumetric radioactive source. According to the framework, we develop the GPPK(GPU-based point kernel gamma dose rate computing) code using GPU programming, to realize the fast dose rate computing in virtual world. The test results show that the GPPK code is play and plug for different scenarios of virtual simulation, has a better performance than CPU-based gamma dose rate computing code, especially on the voxelization of three-dimensional (3D) model. The accuracy of dose rates from the proposed method is in the acceptable range.

• Journal of Korea Water Resources Association
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• v.46 no.9
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• pp.933-946
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• 2013

The quantitative analysis of evapotranspiration (ET) is a key component in hydrological studies and the establishment of water resources planning. Generally, the quantitative analysis of ET is performed by the estimation method of potential or reference ET based on meteorological factors such as air temperature, wind speed, etc. Hargreaves equation is one of empirical methods for reference ET using air temperature data. In this study, in order to estimate more exact reference ET considering climatological characteristics in Korea, parameter regionalization of Hargreaves equation is carried out. Firstly, modified Hargreaves equation is presented after the analysis of the relationship between solar radiation and temperature. Secondly, parameter ($K_{ET}$) optimization of Hargreaves equation is performed using Penman-Monteith method and modified equation at 71 weather stations. Lastly, the equation for calculating $K_{ET}$ using temperature data is proposed and verified. As a result, reference ET from original Hargreaves equation is overestimated or underestimated compared with Penman-Monteith method. But modified equation in this study is more accurate in the climatic conditions of Korea. In addition, the applicability of the equation between $K_{ET}$ and temperature is confirmed.

• Korean Journal of Construction Engineering and Management
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• v.9 no.5
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• pp.127-136
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• 2008

The initial step in the construction process, estimating appropriate construction time and expense is the most important factor that would influence the result of the construction. In order to enhance productivity and efficiency, there is a need to analyze and manage rationally. The purpose of this project is to make a simulation model for all subway tunnel construction based on the NATM method, also give an support equipment that would make available to plan and analyze the construction. The development of simulation model is based on a real case construction analysis process and also on the reference data. It reflects restrictive elements, make it possible to modify the conditions, and not only adapt to our project's construction but other projects as well. The model developed by this project will be able to reasonably predict the construction completion time and support the process of decision making during the planning. Therefore we can expect the productivity and efficiency of the whole construction projects.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.2
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• pp.36-54
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• 2004

The disposition of public parks pursue proper distribution and hierarchy formations on the basis of the neighborhood units theory. However, problems like price of land has brought about a large gap between theories and real conditions. This paper examines the problems of the practical disposition and disposition standards of public parks to solve these contradictions with reference to examples in Japan metro-cities. Study results are as follows; 1) The existing disposition theories are based on the district-boundary of men’s acting and settling down. Therefore, the disposition standards of large-scale parks or special parks beyond the humane scale have not been explained exactly. 2) As city sizes have expanded, these large-scale parks have developed greatly, however, they are located out of urban areas on the ground of nature’s geographical features. As a result, many small parks developed in urban areas. This extreme phenomenon of location would break up proper distribution and hierarchy. 3) Large parks over 4 ha not only take an important role in forming greenbelts but their location is also mainly based on their natural geographical features so that they are absorbed into the network -structure of greenbelts. 4) It is suggested that in planning parks, location and size of large parks over 4 ha should be selected and decided in the relation not with parks but with greenbelts. Parks of 4 ha or below are properly disposed. Also, these parks take a great role in forming the district boundary for settling down. Accordingly, proper distribution and hierarchy formation needs to be based on established neighborhood as they were previously.

• Earthquakes and Structures
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• v.13 no.5
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• pp.443-454
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• 2017

When eccentrically braced steel frames (EBFs) are in the desired failure mode, links yield at each layer and column bases appear plastically hinged. Traditional design methods cannot accurately predict the inelastic behavior of structures owing to the use of capacity-based design theory. This paper proposes the use of performance-based seismic design (PBSD) method for planning eccentrically braced frames. PBSD can predict and control inelastic deformation of structures by target drift and failure mode. In buildings designed via this process, all links dissipate energy in the rare event of an earthquake, while other members remain in elastic state, and as the story drift is uniform along the structure height, weak layers will be avoided. In this condition, eccentrically braced frames may be more easily rehabilitated after the effects of an earthquake. The effectiveness of the proposed method is illustrated through a sample case study of ten-story K-type EBFs and Y- type EBFs buildings, and is validated by pushover analysis and dynamic analysis. The ultimate state of frames designed by the proposed method will fail in the desired failure mode. That is, inelastic deformation of structure mainly occurs in links; each layer of links involved dissipates energy, and weak layers do not exist in the structure. The PBSD method can provide a reference for structural design of eccentrically braced steel frames.

• Journal of the Korean Dietetic Association
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• v.7 no.1
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• pp.9-18
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• 2001

Dietitians in various fields have used food exchange lists for food preparations. However it seems that the present food exchange lists are complicated, thus they cause many problems for dietitians to use in the fields. Therefore this study evaluated to the extent of awareness and utilizations of KDA food exchange lists in dietitians and also collected dietitian's opinions for revising food exchange lists such as serving size, serving calories, and for unifying food guidelines and dietary and dietary guidelines for Korean to one simple guideline. 192 dietitians who presently work in urban and rural areas were recruited and data based on survey were collected. As results, most of dietitians(87.5%) knew well about food exchange lists, but only 7.8% of them always would use food exchange lists for menu planning, 56.3% of dietitians did not use it at all and 34.4% occasionally use it. And 88.0% of dietitians wanted to revise food exchange lists totally or partially, 69.8% of dietitians hoped to amend various calories per one serving in food exchange lists to one serving calorie. The desirable on serving calorie was selected as 100kcal(51%) or 50kcal(38%) by dietitians. The dietitians in this study understood very well dietary guidelines(86.5%) and food guidelines(88.5%) for Korean, and 66.1% dietitians wanted to unify both guidelines. In case of unification of guidelines, dietitians answered that 7-8 items(30%) or 5-6 items(27%) should be included in guideline. In the question about reference value for daily allowance, most dietitians(56%) satisfied with the present various reference values for various generation while 28% of dietitians wanted to change to have one reference value (standard with 2000kcal, adult female). This study will provide basic informations for revising or adjustment of food exchange list and dietary or food guidelines for Korean.

• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.4
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• pp.50-60
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• 1996

The purpose of this study is to investigate the prime factors that affect user satisfaction of area and facilities in urban forests, to classify those factors, to find out factorial structure of user satisfaction about them, and then to suggest important indicators in the urban forest planning, design, and development. The survey research was done using the self-administered questionnaire method by the people in the city of the Pusan who participated in recreational activities in the Mt. Keumjung. Factor analysis was used to extract the prime factors related to the recreational satisfaction concerning the area and facilities of the urban forest by the SPSS program, and then prime factors were used to investigate the factorial structure of user recreational satisfaction in the urban forest by the LInear Structure RELation program. According to the factor analysis concerning the 13 variables, 4 prime factors by the statistical values were considered as effective, indicating, 'health and recreational facilities', 'convenience and management facilities','facilities for the physical and psychological training' and 'historical and cultural areas'. The results of the causal structure analysis were identified as having significant effects mutually on endogenous variables, 'overall recreational satisfaction of the areas and facilities in the Mt. Keumjung','health and recreational facilities','convenience and management facilities','facilities for the psychological training', and 'historical and cultural areas'. But exogenous variables which have significant effects on endogenous variables were also indentified. Overall fits of both causal model were very good. The hypothetical causal structural equation models based on the results found partially significant correlation between dndogenous variables and between envogenous and exogenous variables. These significant relationships indiate important factors and variables that should be considered in planning, design, and development of the urban forests. Therefore, development direction of the Mt. Keumjung has to be analyzed as significant factors concerning user recreational satisfaction in a systematic was, recognized as important variables for planning process. The plan for development and management also should reflect the natural conservation policy from the environmental conservation movement like natural conservation advertisement and environmental education.

• Journal of Korean Neurosurgical Society
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• v.53 no.2
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• pp.102-107
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• 2013

Objective : The Leksell Gamma Knife$^{(R)}$ (LGK) is based on a single-fraction high dose treatment strategy. Therefore, independent verification of the Leksell GammaPlan$^{(R)}$ (LGP) is important for ensuring patient safety and minimizing the risk of treatment errors. Although several verification techniques have been previously developed and reported, no method has ever been tested statistically on multiple LGK target treatments. The purpose of this study was to perform and to evaluate the accuracy of a verification method (modified variable ellipsoid modeling technique, MVEMT) for multiple target treatments. Methods : A total of 500 locations in 10 consecutive patients with multiple brain tumor targets were included in this study. We compared the data from an LGP planning system and MVEMT in terms of dose at random points, maximal dose points, and target volumes. All data was analyzed by t-test and the Bland-Altman plot, which are statistical methods used to compare two different measurement techniques. Results : No statistical difference in dose at the 500 random points was observed between LGP and MVEMT. Differences in maximal dose ranged from -2.4% to 6.1%. An average distance of 1.6 mm between the maximal dose points was observed when comparing the two methods. Conclusion : Statistical analyses demonstrated that MVEMT was in excellent agreement with LGP when planning for radiosurgery involving multiple target treatments. MVEMT is a useful, independent tool for planning multiple target treatment that provides statistically identical data to that produced by LGP. Findings from the present study indicate that MVEMT can be used as a reference dose verification system for multiple tumors.

• Korean Journal of Community Nutrition
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• v.23 no.5
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• pp.411-423
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• 2018

Objectives: The purpose of this study was to develop new meal planning tools for a nutritionally balanced diet. Methods: Based on the food exchange list for diabetes, we adjusted the food group classification system to reflect the suggested nutritional factors for chronic disease prevention and health promotion. We developed a nutritionally balanced dietary profile for adults and compared it with the dietary reference intakes for Koreans (KDRIs) and the food pattern recommended by the Korean Diabetes Association. Results: The newly developed menu planning tools are the LOHAS food exchange table and the LOHAS food pattern. Our recommended daily 1,800 kcal dietary composition for adults is as follows: The carbohydrate food group consists of 4 'whole grains', 3 'refined grains', 2 'sugars', 9 'vegetables', 3 'starchy vegetables', 2 'fruits' and 1 'high sugar fruits'. The protein food group includes 3 'plant protein foods', 3 'animal protein foods (low-fat)', and 1 'animal protein foods (high-fat)'. The fat food group consists of 2 'oils and nuts' and 1 'solid fats'. The total number of calories is estimated at 1,840 kcal and the energy ratio is 62% carbohydrate, 18% protein, 20% fat, 6.8% saturated fat and 13.2% sugars. Using the LOHAS food exchange table, it is possible to estimate values of saturated fat, unsaturated fat, dietary fiber, and sugars besides carbohydrate, protein and fat. It is also possible to compose a dietary design considering carbohydrate, sugars, saturated fat and dietary fiber. The LOHAS food pattern provides benefits for the management of both institutional food services and individual meals, as it can help reduce the levels of saturated fat and sugar intake and help develop healthy meals rich in unsaturated fats and dietary fiber. Conclusions: The LOHAS food exchange table and LOHAS food pattern are expected to be practical tools for designing and evaluating nutritionally balanced diets.

• Journal of Korean Society of Rural Planning
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• v.27 no.1
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• pp.9-20
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• 2021

In order to develop practical indicator that can diagnose the regional conditions and characteristics of fishing villages, this study reviewed domestic and foreign researches and selected the diagnostic indicator of fishing villages by spatial unit. The major categories are divided into population and society, economic conditions, and living conditions. The middle categories consists of population, household, industry, tourism, settlement, environment, safety, health and welfare, education, and culture and leisure. The indicator were selected with reference to the existence of statistical data officially provided according to the spatial range(Si/Gun, eup/myeon, village). Based on the selected indicator, the test evaluation was conducted in Jindo-gun, Jeollanam-do by applying data that can be obtained from KOSIS and web GIS. It is judged that the diagnostic indicator developed through this research can be used in various ways from the planning stage to the implementation stage of the regional development project, such as grasping the current conditions, setting improvement targets, promotion and evaluation/monitoring of the project. In addition, it is expected that it will be possible to carry out regional diagnosis for each spatial unit and to plan and implement regional development projects by giving priority to areas where the level of each department is insufficient.