• Title/Summary/Keyword: distribution concepts

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Conceptual design of a high neutron flux research reactor core with low enriched uranium fuel and low plutonium production

  • Rahimi, Ghasem;Nematollahi, MohammadReza;Hadad, Kamal;Rabiee, Ataollah
    • Nuclear Engineering and Technology
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    • v.52 no.3
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    • pp.499-507
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    • 2020
  • Research reactors for radioisotope production, fuel and material testing and research activities are designed, constructed and operated based on the society's needs. In this study, neutronic and thermal hydraulic design of a high neutron flux research reactor core for radioisotope production is presented. Main parameters including core excess reactivity, reactivity variations, power and flux distribution during the cycle, axial and radial power peaking factors (PPF), Pu239 production and minimum DNBR are calculated by nuclear deterministic codes. Core calculations performed by deterministic codes are validated with Monte Carlo code. Comparison of the neutronic parameters obtained from deterministic and Monte Carlo codes indicates good agreement. Finally, subchannel analysis performed for the hot channel to evaluate the maximum fuel and clad temperatures. The results show that the average thermal neutron flux at the beginning of cycle (BOC) is 1.0811 × 1014 n/㎠-s and at the end of cycle (EOC) is 1.229 × 1014 n/㎠-s. Total Plutonium (Pu239) production at the EOC evaluated to be 0.9487 Kg with 83.64% grade when LEU (UO2 with 3.7% enrichment) used as fuel. This designed reactor which uses LEU fuel and has high neutron flux and low plutonium production could be used for peaceful nuclear activities based on nuclear non-proliferation treaty concepts.

Considerations on an Oriental Medical Doctor like Indentation System (한의사 맥진 가압력 재현에 대한 고찰)

  • Lee, Jeon;Woo, Young-Jae;Jeon, Young-Ju;Lee, Yu-Jung;Ryu, Hyun-Hee;Kim, Jong-Yeol
    • Korean Journal of Oriental Medicine
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    • v.14 no.3
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    • pp.113-119
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    • 2008
  • In pulse diagnosis, the indentation pressure is one of the most important factors as well as the change of pulse shape and the distribution of pressure via time. But, on the oriental medical doctor's indentation pressure control, the understandings of the neurophysiological meanings and mechanisms have been lacked. So, in this paper, we considered on these issues and then proposed a proper system which can imitate the OMD's indentation pressure control mechanisms. As a result, both tactile information and kinesthetic information were found to be essential to the indentation pressure control so that a system, which can measure both the physical indent pressure and the displacement of an indentation arm, has been proposed. With this proposed system, while the indentation was being controlled through the moving step number of the step motor, the physical indentation pres sure and displacement of the indentation arm were measured. From these measured data, the relationships between the moving step number and both physical indentation pressure and displacement were revealed to have linear characteristics in early phase and to have nonlinear characteristics in latter phase. Additionally, three types of graph were generated whose X axis means the moving step number, the physical indentation pressure and the displacement respectively and Y axis means the pulse pressure. By comparing these graphs, we come to conclude that different concepts on indentation pressure control cause different diagnostic results on floating/sinking degrees for the same subject. Consequently, an indentation system for the pulse diagnosis should be able to provide both the tactile information and kinesthetic information, that is, the physical indentation pressure and the displacement of the indentation arm. In future, the proposed system should be optimized to the pulse diagnosis environment and how to combine the both information for more reliable diagnosis should be studied.

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Alternative Methods for Assessments of DEMs' Erros (DEM의 오차 평가 방법에 관한 연구)

  • Hwang, Chul-Sue
    • Journal of Korean Society for Geospatial Information Science
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    • v.7 no.2 s.14
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    • pp.23-34
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    • 1999
  • The most widely used measure for indicating the accuracy of DEM is RMSE(nut Mean Square Error), which is used by many national mapping agencies such as the USGS and the Ordnance Survey. Its prevalent use can be followed by the relative ease of calculation and understanding the concepts. However, there are many problems with the measure and the way from which it is often derived. First of all, the index does not involve my description of the mean donation between the two measures of elevation,. This means that it cannot interpret the distributions or patterns of errors involved in DEMs. The distribution of errors in DEMs will show some forms of spatial patterning. In order to explore the real quality of DEMs as a useful database, alternative approaches are needed. In this paper, we examined so called ESDA(Exploratory Spatial Data Analysis) approaches, which were attributed by both aspatial and spatial exploration methods. Our experimental research shows that even simple ESDA methods reveal new aspects of errors, especially spikes, striation, and terracing effect in DEMs, which my be ignored by RMSE measure.

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An Integrative Review Of Oncology Nursing Research In Korea: 1998-2003 (국내 종양간호연구 동향에 관한 연구)

  • Oh, Pok-Ja
    • Asian Oncology Nursing
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    • v.3 no.2
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    • pp.112-121
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    • 2003
  • The purpose of these study was to analyze the contents and trend of researches done on oncology nursing in the past five years in Korea and to suggest its direction for the future research. Methods: 214 nursing studies published from 1998 to 2003 were selected for the analysis. They were examined for the source, design of study, type of subjects, the intervention outcomes of experimental research, the key words and theme of the oncology research. Results: 1. 139(64.9%) of 214 studies were masters thesis and doctoral dissertations. There were 196(91.6%) quantitative researches and 18 qualitative researches. Quantitative research consisted of 28(14.3%) experimental and 168(85.7%) non- experimental studies. Among non-experimental studies, there were 53 correlations, 78 descriptives, 14 comparatives and 23 methodological studies. 2.The main subjects of the study were cancer patients in general(43.7%) and breast cancer patients (18.3%). According to the treatment types, patients receiving chemotherapy were the highest number distribution as 23 of all researches. 3. Social support, fatigue, stress, hope, and quality of life were the most frequently used concepts in correlational studies.4. Education, providing information, oral care, exercise, relaxation and foot massage were the most frequent nursing interventions. Most frequently measured outcomes variable were self-care, pain control, nausea & vomiting, oral discomfort and anxiety. 5. Key words used most frequently were quality of life, educational need, pain controls and fatigue. 6. The themes of qualitative researches were illness experience, family experience and adaptation process. More than 50% of qualitative researches used phenomenologic method. Conclusion: Researches on cancer nursing in Korea have been increased. Descriptive design is being dominant and few experimental studies are being done For the future, it is necessary to conduct international studies to compare, replicate and to establish the effective nursing interventions.

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Fuel Cell End Plates: A review

  • Kim, Ji-Seok;Park, Jeong-Bin;Kim, Yun-Mi;Ahn, Sung-Hoon;Sun, Hee-Young;Kim, Kyung-Hoon;Song, Tae-Won
    • International Journal of Precision Engineering and Manufacturing
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    • v.9 no.1
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    • pp.39-46
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    • 2008
  • The end plates of fuel cell assemblies are used to fasten the inner stacks, reduce the contact pressure, and provide a seal between Membrane-Electrode Assemblies (MEAs). They therefore require sufficient mechanical strength to withstand the tightening pressure, light weight to obtain high energy densities, and stable chemical/electrochemical properties, as well as provide electrical insulation. The design criteria for end plates can be divided into three parts: the material, connecting method, and shape. In the past, end plates were made from metals such as aluminum, titanium, and stainless steel alloys, but due to corrosion problems, thermal losses, and their excessive weight, alternative materials such as plastics have been considered. Composite materials consisting of combinations of two or more materials have also been proposed for end plates to enhance their mechanical strength. Tie-rods have been traditionally used to connect end plates, but since the number of connecting parts has increased, resulting in assembly difficulties, new types of connectors have been contemplated. Ideas such as adding reinforcement or flat plates, or using bands or boxes to replace tie-rods have been proposed. Typical end plates are rectangular or cylindrical solid plates. To minimize the weight and provide a uniform pressure distribution, new concepts such as ribbed-, bomb-, or bow-shaped plates have been considered. Even though end plates were not an issue in fuel cell system designs in the past, they now provide a great challenge for designers. Changes in the materials, connecting methods, and shapes of an end plate allow us to achieve lighter, stronger end plates, resulting in more efficient fuel cell systems.

From Computing Distribution of Email Responses for Each User Cluster To Construct User Preference based Anti-spam Mail System (사용자 클러스터별 이메일 반응 분포 계산 및 사용자 선호 스팸 메일 대응 시스템 구축)

  • Kim, Jong-Wan
    • Journal of the Korean Institute of Intelligent Systems
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    • v.19 no.3
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    • pp.343-349
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    • 2009
  • In this paper, it would be shown that individuals can have different responses to the same email based on their preferences through computing the distributions of user clusters' email responses from clustering results based on email users' preference information. This paper presents an approach that incorporates user preferences to construct an anti-spam mail system, which is different from the conventional content-based ones. We consider email category information derived from the email content as well as user preference information. We also build a user preference ontology to formally represent the important concepts and rules derived from a data mining process and then apply a rule optimization procedure to exclude unnecessary rules. Experimental results show that our user preference based system achieves good performance in terms of accuracy, the rules derived from the system and human comprehensibility.

A Study on the Current State of Outdoor Clothing Companie and their Comparison and Analysis according to the Items (등산복 업체현황 및 아이템별 패턴 비교분석 연구)

  • Lee, Eun-Hye
    • Journal of the Korean Society of Clothing and Textiles
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    • v.35 no.9
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    • pp.1049-1059
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    • 2011
  • This study investigates the current state of companies that manufacture and sell outdoor wear. A survey was conducted to identify what problems they had and what aspects they needed to supplement through a comparison and analysis of their block patterns. Companies that manufactured outdoor wear and those that sold them were separately surveyed to understand their current state. The manufactures included 4 companies and 14 sellers. The survey used interviews to cover the areas of target consumers, development patterns, production lines, body size, nominal size, production size, and functional materials for each item, and aspects that need improvement. The survey period was from September $3^{rd}$ to $10^{th}$ 2008. There were three block patterns for jackets, T-shirts, and pants. The investigator collected the patterns used by three outdoor clothing manu-facturers for comparison and assessment. As a result, the mean age of the target consumers set by the outdoor clothing manufacturers and sellers was 25.3-50.7 and 29.2-42.5, respectively, which shows that the outdoor clothing had a wider distribution of target consumers than the sellers. It is imperative for them to segment and differentiate the target consumers and concepts. The basic body measurements the companies used to draw the upper and lower garment patterns were the bust circumference for the upper garment patterns and the waist circumference for the lower garment patterns. The basic nominal size was 95 for the upper garment and 70 for the lower garment. Also analyzed were the block patterns according to the items to understand the pattern characteristics of each of the companies. There were a total of 35, 36, and 30 items for the jackets, T-shirts, and pants, respectively, to measure size. The items were then compared with one another in mean and standard deviation. The analysis indicate that the block patterns were not fit for women in their twenties or thirties to wear and required revisions in the length of the upper garment, the height of sleeve cap, bust circumference, hip length, and pant length.

The Concept and Actual Conditions of Inequality (소득불평등 개념과 실태)

  • Yoo, Gyeongjoon
    • Journal of Labour Economics
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    • v.30 no.3
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    • pp.103-138
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    • 2007
  • The purpose of this study is: (1) to compare the awareness of inequality concept between Korea and other countries using the survey, (2) to identify whether several inequality measures, which have diverse concepts, are different in empirical aspect, and (3) to suggest the direction for the income distribution policy in Korea. The results of the survey has shown a surprising fact in that the majority of respondents do not agree with the basic assumptions outlined by Gini coefficient, which is the relative inequality measures that had been generally accepted in the past. These results are very similar to those of other countries. However, the major difference with other countries is that the Koreans feel that absolute income inequality-the income gap between the poor and rich, has increased more than relative income inequality, when all incomes of social members are doubled. From the result it is difficult to say that the bi-polarization index is different from Gini coefficient in statistical aspect although it has different theoretical background. The national development strategy should seek to promote "the pro-poor growth" since the change of inequality affect differently on the change of growth and inequality depending on whether the inequality change is relative or absolute.

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The Effect of Clothing Satisfaction, Body Cathexis, and School Achievement Related to Social Self-esteem (의복 및 신체 만족도와 학업성취도가 사회적 자아존중감에 미치는 영향)

  • Kim Yang Jin;Kahng He Won
    • Journal of the Korean Society of Clothing and Textiles
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    • v.16 no.2
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    • pp.197-209
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    • 1992
  • The purposes of this study were 1) to investigate high school girls' overall clothing satisfac-tion and self concepts, 2) to clarify the relationship between clothing satisfaction and self concept in terms of body cathexis, school achievement and social self-esteem, and 3) to find out the social self-esteem differences among the groups related to the high and low levels of clothing satisfaction, body cathexis as well as school achievement. Body Cathexis was measured by the Secord and Jofrard's Body Cathexis Scale. School achievement and social self-esteem were assessed with the modified questionnaires based on the previous researches. Clothing satisfaction which included 3 aspects was measured by the questionnaires developed for this study. The questionnaire was administered to 464 high school students in Seoul, and the data were aiialyzed by frequency, 1-test, one-way·ANOVA and SNK test, Pearson's product moment correlation and factor analysis. The results of this study were as follows: 1) High-school girls 'body' cathexis showed low levels of mean and distribution, wheareas school achievement and social self-esteem showed high levels of those.2) There werf significant positive correlation between clothing satisfaction and all of the self concept variables. In addition, positive correlation were found among the three self concept variables. 3) Three clothing satisfaction factors were emerged and named as clothing possession, clothing selection ability and parent's clothing restriction. Clothing posses- sion and parent's clothing restriction were generally satisfied. 4) School achievement was the most influencial variable for the level of serial self-esteem. It was thought that body dissatisfac-tion would be relieved by the high clothing satisfaction.

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Design of Framework for Implementation of the New Paradigm Map (신 패러다임 맵 구현을 위한 프레임워크 설계)

  • Kim, Sun-Woo;Yang, Kwang-Ho;Park, Ki-Shik;Park, Ju-Young;Ra, In-Ho
    • The Journal of the Korea Contents Association
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    • v.15 no.3
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    • pp.32-39
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    • 2015
  • In this paper, We propose the futuristic map using variety technology of advanced ICT-based. The futuristic maps are expected to developed into a new format of user participation to express the results in various formats through the understanding and interpretation of the facts and phenomena of tangible and intangible that exist in the real world. In the future, the map is expected to be developed into form of a new paradigm map made in real time that economy, industry, the collection of information necessary for everyday life, processing, usage, analysis, distribution and sharing. In this paper, we provide a real-time personalized contents to digitize the information of the real space based on the concept of map, databases, spatial analysis and describes the key technologies that characterized by the representation of time-series data by analyzing and prediction every field macro phenomena of society, economy, culture and etc. And we establish the concepts of the 'New Paradigm Map' for future creative economy.