• Nuclear Engineering and Technology
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• 제51권5호
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• pp.1436-1443
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• 2019

A fast gamma-ray dose rate assessment method for complex geometries based on stylized model reconstruction and point-kernel method is proposed in this paper. The complex three-dimensional (3D) geometries are imported as a 3DS format file from 3dsMax software with material and radiometric attributes. Based on 3D stylized model reconstruction of solid mesh, the 3D-geometrical solids are automatically converted into stylized models. In point-kernel calculation, the stylized source models are divided into point kernels and the mean free paths (mfp) are calculated by the intersections between shield stylized models and tracing ray. Compared with MCNP, the proposed method can implement complex 3D geometries visually, and the dose rate calculation is accurate and fast.

• Computers and Concrete
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• 제2권1호
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• pp.31-53
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• 2005

In the present structural codes the safety verification is based on a linear analysis of the structure and the satisfaction of ultimate and serviceability limit states, using a semi-probabilistic security format through the consideration of partial safety factors, which affect the action values and the characteristic values of the material properties. In this context, if a non-linear structural analysis is wanted a difficulty arises, because the global safety coefficient, which could be obtained in a straightforward way from the non-linear analysis, is not directly relatable to the different safety coefficient values usually used for the different materials, as is the case for reinforced concrete structures. The work here presented aims to overcome this difficulty by proposing a methodology that generalises the format of safety verification based on partial safety factors, well established in structural codes within the scope of linear analysis, for cases where non-linear analysis is needed. The methodology preserves the principal assumptions made in the codes as well as a reasonable simplicity in its use, including a realistic definition of the material properties and the structural behaviour, and it is based on the evaluation of a global safety coefficient. Some examples are presented aiming to clarify and synthesise all the options that were taken in the application of the proposed methodology, namely how to transpose the force distributions obtained with a non-linear analysis into design force distributions. One of the most important features of the proposed methodology, the ability for comparing the simplified procedures for second order effects evaluation prescribed in the structural codes, is also presented in a simple and systematic way. The potential of the methodology for the development and assessment of alternative and more accurate procedures to those already established in codes of practice, where non-linear effects must be considered, is also indicated.

• 한국과학교육학회지
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• 제34권1호
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• pp.1-9
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• 2014

이 연구는 과잉효능감과 과잉확신이 선다형과 서답형 평가에서 어떻게 나타나는지에 조사하였다. 이 연구를 위하여 204명의 여자중학교 학생들이 참여하였다. 선다형과 서답형으로 된 광합성 개념에 대한 검사도구를 사용하였으며, 각 문항마다 자신의 효능감과 확신을 척도로 나타나게 하였다. 연구결과 선다형과 서답형의 상관관계는 0.5가 채 되지 않았으며, 학생들이 생각하는 자신의 문제 해결 능력(효능감)과 실제 능력 간의 상관관계 역시 0.45가 되지 않았다. 학생들은 선다형 문제 해결 과정에서 지식에 대한 확신을 높이는 경향을 보였다. 선다형 문항을 먼저 수행한 집단에서는 그렇지 않은 집단에 비하여 과잉효능감과 과잉확신의 비율이 더 높게 나타났다. 이 연구 결과는 학생들을 평가하는 과정에서 서답형의 사용을 늘릴 것을 제언한다. 또한 두 형태의 검사도구를 동시에 사용하게 될 경우 선다형 검사도구를 사후에 사용하여 학생들이 적절한 수준의 효능감과 확신을 유지할 수 있도록 해야 될 것이다.

• 환경영향평가
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• 제1권1호
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• pp.41-50
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• 1992

To prevent unwanted visual impacts of proposed projects before they are actually built, Visual Impact Assessment(VIA) is conducted in current landscape planning and management process. The application of VIA to actual projects raises some important questions: "What views will the project affect?" "What tools and techniques are effective for predicting and portraying future landscape conditions?" "Who should determine the value of the impacts?" and "How can the impacts be measured?" Types and levels of visual impacts should be decided through analyzing both the existing landscape and the proposed project. Computer-based visual simulations will play a pivotal role as effective prediction and communication tools. With professionals' assistance, the public participation in the VIA process will produce meaningful solutions for planning and managing the future landscape. Also, the use of a proper response format and sensitive assessment criteria in measuring the public's opinion will enrich outcomes of the assessment. Based on the methodological framework, the case study briefly explains an application of VIA to an actual project.

• 대한기계학회논문집A
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• 제24권5호
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• pp.1331-1342
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• 2000

In power generation systems a variety of structural components typically operate at high temperature and pressure. Therefore a life assessment methodology accounting for gradual creep fracture is increasingly needed for these components. The most critical defects in such structure are generally found in the form of semi-elliptical surface cracks in the welded tubular joints. Therefore the analysis of a semi-elliptical surface crack in a plate or a shell is an important problem in engineering fracture mechanics. On this background, via shell/line-spring finite element analyses of such surface cracks in the welded T and L joints under various loadings, we investigate J-integral along the crack front We first develop T and L joints auto mesh generation program providing ABAQUS input file composed of shell/line-spring finite elements. We then further develop a T and L joints life assessment program based on the experimental creep crack growth law and auto mesh generation program in a graphical user interface format Finally the remaining life of T and L joints for various analytical parameters are assessed using the developed life assessment program.

• 한국전문물리치료학회지
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• 제7권1호
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• pp.1-21
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• 2000

The purposes of this study were to research the current state of evaluation of children with delayed development and cerebral palsy and determine pediatric physical therapists' knowledge of assessment tools and their use. The subjects were 130 pediatric physical therapists (general hospitals, university-related hospitals, rehabilitation centers, etc.). Data was obtained from August 24, 1999 to October 18, 1999 by means of a survey questionnaire. The results were as follows: 1. The current state of pediatric physical therapist evaluation of children with delayed development and cerebral palsy. 1) Tools used to assess functional areas of children with cerebral palsy were: subjective description format-128 (47.1%); the GMFM-58 (21.3%); facility-generated tool-51 (18.8%); and DDST-15 (5.5%). 2) Tools used to assess developmentally delayed children were: subjective description format-121 (50.6%); the GMFM-43 (18.0%); facility-generated tool-41 (17.2%); and DDS T-14 (5.9%). 3) After their college or university study, therapists who had attended lectures on evaluation were 113 (86.9%); 13 (10.0%) therapists had not attended any lectures on evaluation 2. Test scores of physical therapists' professional knowledge of evaluation procedures: high (more than 36 points)-74 (56.9%); moderate (18~35 points)-39 (30.0%); and low (below 17 points)-none. 1) For therapists treating cerebral palsied children, 73 (65.2%) were in the high range, 39 (34.8%) were in the moderate range and none were in the low range. 2) For therapists treating children with delayed development, 71 (65.7%) were in the high range, 37 (34.3%) were in the moderate range and none were in the low range. Although the general degree of professional knowledge of evaluation was quite high, there was a lack of variety in the assessment tools used With a large number of therapists depending on subjective description. Possible reasons for the low rate of objective asses sment tool use: 1) Poor clinical environment: too many clients and lirnited treatment time. 2) Lack of any medical insurance fee category for specific assessment tools. 3) Lack of continuing education opportunities in pediatric evaluation skills during or after either college-based (3 year) or university-based (4 year) education programs. Based on the study results, provision of more extended educational opportunities would promote the use of a greater variety of objective assessment tools by pediatric physical therapists.

• 농촌계획
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• 제19권4호
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• pp.47-54
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• 2013

Climate change is the most direct threatening factors in sustaining agricultural productivity. It is necessary to reduce the damages from the natural hazards such as flood, drought, typhoons, and snowstorms caused by climate change. Through the vulnerability assessment to adapt the climate change, it is possible to analyze the priority, feasibility, effect of the reduction policy. For the vulnerability assessment, broad amount of weather data for each meterological station are required. Making the database management system for the meteorologic data could troubleshoot of the difficulties lie in handling and processing the weather data. In this study, we generated the meteorologic data retrieval system (MetSystem) for climate change vulnerability assessment. The user interface of MetSystem was implemented in the web-browser so as to access to a database server at any time and place, and it provides different query executions according to the criteria of meteorologic stations, temporal range, meteorologic items, statistics, and range of values, as well as the function of exporting to Excel format (*.xls). The developed system is expected that it will make it easier to try different analyses of vulnerability to natural hazards by the simple access to meteorologic database and the extensive search functions.

• 한국환경보건학회지
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• 제43권5호
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• pp.412-421
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• 2017

Objectives: To establish a system for integrated risk assessment of EDCs in Korea, infrastructure for providing toxicity data of ecological media should be established. Some systems provide soil ecotoxicity databases along with aquatic ecotoxicity information, but a well-structured ecotoxicity database system is still lacking. Methods: Aquatic and soil ecotoxicological information were collected by a toxicologist based on a human readable data (HRD) format for collecting ecotoxicity data that we provided. Among these data, anomalies were removed according to database normalization theory. Also, the data were cleaned and encoded to establish a machine-readable data (MRD) ecotoxicity database system. Results: We have developed a multi-purpose ecotoxicity database model focusing on EDCs, ecological species, and toxic effects. Also, we have constructed a web-based data searching system to retrieve, extract, and download data with greater availability. Conclusions: The results of our study will contribute to decision-making as a tool for efficient ecological risk assessment of EDCs in Korea.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.805-807
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• 2005

A basic assessment is presented of the technical, economic and strategic challenges expected for manufacturing displays in a roll-to-roll format. Two general pathways are considered; one that results in dramatic cost reductions but results in sacrificing product performance, and another which is an extension of the conventional FPD cost-reduction from increased substrate size. While Roll-to-Roll fabrication is fundamentally possible, feasibility experiments will be required to address the most significant technical challenge: achieving and managing acceptable yield. In all respects, the efforts to achieve RTR manufacturing will be assisted by overlapping interests in other application areas such as flex circuit, photovoltaics and large area lighting.

• 신재생에너지
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• 제6권2호
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• pp.5-11
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• 2010

This paper reviews three commercial softwares for wind climate data analysis in wind resource assessment; WAsP/Observed Wind Climate, WindRose and Windographer. Windographer is evaluated as the best software because of its variety of input data format, analysis functions, easiness of user interface, etc. For a quantitative understanding of uncertainty depending on software selection, a benchmark is carried out with the met-mast observation dataset at the Gimnyeong Wind Turbine Performance Test Site. It is found that Weibull parameter calculation and air density correction have a dependency on the software so that such uncertainty should be considered when an analysis software is selected. It is confirmed that annual energy production calculated by WAsP using a statistical table of frequency of occurrence may have some error compared to a time-series calculation method used by the other softwares.