• Title/Summary/Keyword: concept and method

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Analyses of the Double-Layered Repository Concepts for Spent Nuclear Fuels (사용후핵연료 심지층 처분장 복층개념 분석)

  • Lee, Jongyoul;Kim, Hyeona;Lee, Minsoo;Choi, Heui-Joo;Kim, Kyungsu
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.15 no.2
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    • pp.151-159
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    • 2017
  • A deep geological disposal at a depth of 500 m in stable host rock is considered to be the safest method with current technologies for disposal of spent fuels classified as high-level radioactive waste. The most important requirement is that the temperature of the bentonite buffer, which is a component of the engineered barrier, should not exceed $100^{\circ}C$. In Korea, the amount of spent fuel generated by nuclear power generation, which accounts for about 30% of the total electricity, is continuously increasing and accumulating. Accordingly, the area required to dispose of it is also increasing. In this study, various duplex disposal concepts were derived for the purpose of improving the disposal efficiency by reducing the disposal area. Based on these concepts, thermal analyses were carried out to confirm whether the critical disposal system requirements were met, and the thermal stability of the disposal system was evaluated by analyzing the results. The results showed that upward 75 m or downward 75 m apart from the reference disposal system location of 500 m depth would qualify for the double layered disposal concept. The results of this study can be applied to the establishment of spent fuel management policy and the design of practical commercial disposal system. Detailed analyses with data of a real disposal site are necessary.

Evaluation of the Degrees of Genetic Connectedness Among Duroc Breed Herds (국내 두록종 농장간 유전적 연결성 추정)

  • Cho, Chungil;Choi, Jaekwan;Park, Byoungho;Kim, Sidong;Kwon, Ohsub;Choi, Youlim;Choy, Yunho
    • Journal of Animal Science and Technology
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    • v.54 no.5
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    • pp.337-340
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    • 2012
  • The genetic connectedness between herds is an essential requirement to make robust across-herd estimation of the breeding values of the animals. In this study, genetic connectedness between herds was evaluated by a connectedness rating method. A total of 24,971 records of days to 90 kg (D90KG) of the pigs on performance testing programs collected from six herds (labeled from 'A' to 'F') of Duroc breed along with pedigree information comprising 456,697 families were used. Results showed that a total of eight boars were used for semen exchange programs among participant farms. Herds 'A' through 'E' were found strongly connected among them. But 'F' herd was genetically connected strongly only with 'A' herd. The highest average connectedness rating was 91.7% between 'A' herd and 'C' herd. The lowest average connectedness rating was 65.1% between 'D' and 'F'. The concept of a single genetic group comprising six Duroc herds studied is meaningful due to high connectedness rates among them. Therefore, with this high genetic ties between participant Duroc farms, the more accurate genetic evaluation would be possible.

Communal Ontology of Landmarks for Urban Regional Navigation (도시 지역 이동을 위한 랜드마크의 공유 온톨로지 연구)

  • Hong, Il-Young
    • Journal of the Korean Geographical Society
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    • v.41 no.5 s.116
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    • pp.582-599
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    • 2006
  • Due to the growing popularity of mobile information technology, more people, especially in the general public, have access to computerized geospatial information systems for wayfinding tasks or urban navigation. One of the problems with the current services is that, whether the users are exploring or navigating, whether they are travelers who are totally new to a region or long-term residents who have a fair amount of regional knowledge, the same method is applied and the direction are given in the same way. However, spatial knowledge for a given urban region expands in proportion to residency. Urban navigation is highly dependent on cognitive mental images, which is developed through spatial experience and social communication. Thus, the wayfinding service for a regional community can be highly supported, using well-known regional places. This research is to develop the framework for urban navigation within a regional community. The concept of communal ontology is proposed to aid in urban regional navigation. The experimental work was implemented with case study to collect regional landmarks, develop the ontological model and represent it with formal structure. The final product of this study will provide the geographical information of a region to the other agent and be the fundamental information structure for cognitive urban regional navigation.

Area-Averaged Solution of Peening Residual Stress Using a 3D Multi-impact Symmetry-cell FE Model with Plastic Shots (소성숏이 포함된 3차원 다중충돌 대칭-셀 해석모델을 이용한 면적평균 피닝잔류응력해)

  • Kim, Tae-Hyung;Lee, Hyung-Yil
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.33 no.4
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    • pp.310-320
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    • 2009
  • In this paper, we estimate area-averaged solution of peening residual stress using a 3-D multi-impact symmetry-cell FE model. The symmetry-cell model includes factors reflecting peening phenomena and plastic shot. Area-averaged solution is much closer to XRD experimental solution than 4-node-averaged solution in plastic shot FE model. We then obtain FE Almen saturation curve corresponding to experimental Almen curve based on area-averaged solution. Using the curve, we obtain FE area-averaged solution in major peening materials, and compare the FE solution with experimental solution. In peening materials, surface, maximum compressive residual stress and deformation depth reach experimental solutions. Thus, FE Almen curve is useful for estimation of residual stress solution and could improve the efficiency of peening process. Consequently, it is confirmed that concept of area-averaged solution is the realistic analytical method for evaluation of peening residual stress.

An Experimental Study on the Sorption Properties of Uranium(VI) onto Bentonite Colloids (벤토나이트 콜로이드에 대한 우라늄(VI) 수착특성에 대한 실험적 연구)

  • Baik Min-Hoon;Cho Won-Jin;Hahn Pil-Soo
    • Proceedings of the Korean Radioactive Waste Society Conference
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    • 2005.06a
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    • pp.239-247
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    • 2005
  • In this study, an experimental study on the sorption properties of uranium(VI) onto bentonite colloids generated from a domestic calcium bentonite (called as Gyeongju bentonite). Gyeongju bentonite has been considered as a potential candidate buffer material in the Korean disposal concept for high-level radioactive wastes. The size and concentration of the bentonite colloids used in the sorption experiment were measured by a filtration method. The result showed that the concentration of the synthesized bentonite colloid suspension was 5100ppm and the size of the most of bentonite colloids(over $98\%$) was in the range of 200-450nm in diameter. The amount of uranium lost by the sorption onto bottle walls, by precipitation, and by ultrafiltration or colloid formation was analyzed by carrying out some blank tests. The loss of uranium by the ultrafiltration was significant in the lower ionic strength(i.e., in the case of 0.001M $NaClO_4$) due to the cationic sorption effect onto the ultrafilter by a surface charge reversion. The distribution coefficient (or pseudo-colloid formation constant) for the sorption of uranium(VI) onto bentonite colloids was $10^4^{\sim}10^6$ mL/g depending upon pH and the distribution coefficient was highest in the neutral pH around 6.5.

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Prospective of Nursing Research based on Analysis of Doctoral Dissertations in Nursing at Seoul National University (서울대 간호학 박사학위논문 분석을 통한 간호학 연구의 경향)

  • An, Gyeong-Ju;Ham, Eun-Mi;Park, Kwang-Hee;Kang, Ji-Yeon;Park, Sung-Hee;Lee, Hee-Ju;Ryu, Sea-Ang;Yi, Myung-Sun;Kim, Keum-Soon;Choe, Myoung-Ae;Lee, So-Woo;Lee, Eun-Ok
    • Perspectives in Nursing Science
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    • v.1 no.1
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    • pp.85-102
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    • 2004
  • Purpose: The purpose of this study was to identify the trend of nursing research by analyzing doctoral dissertations of nursing college at Seoul National University. Method: The doctoral dissertations used in this study were 69 thesis from 1989 to 2001. The methodological characteristics, theory, philosophy and world view in these thesis were explored. Key words were classified according to metaparadigm and were compared with MeSH term. Result: There were 54 dissertations of quantitative research and 12 dissertations of qualitative research. Most of subjects of the thesis were patients with 20~65 years old. The written consent to participate in research was not described in great part of thesis. As to measurement, questionnaire was most frequent used. In independent variables cognitive nursing interventions were used frequently. Psychosocial variables as a dependent variable were used mainly. In theory level of research, situation-producing research was performed. In type of nursing knowledge according to Caper many dissertations studied about empirical knowledge. More than half of doctoral dissertations used borrowed theory from nursing related disciplines. Most of studies were done within empirical positivism and organic viewpoint. Key words related to the concept of environment among four metaparadigm has been insufficiently studied. English key words in doctoral thesis were out of accordance largely with MeSH term English. Conclusion: These results show that it is necessary to develop the nursing theory for nursing knowledge body.

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A Study On The Thermal Movement Of The Reactor Coolant System For PWR (가압 경수로의 냉각재 계통 열팽창 거동에 관한 연구)

  • Yoon, Ki-Seok;Park, Taek sang;Kim, Tae-Wan;Jeon, Jang-Hwan
    • Nuclear Engineering and Technology
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    • v.27 no.3
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    • pp.393-402
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    • 1995
  • The structural analysis of the reactor coolant system mainly consist of too fields. The one is the static analysis considering the impact of pressure and temperature built up during normal operation. The other is the dynamic analysis to estimate the impact of postulated events such as the seismic loads or postulated branch line pipe breaks event. Since the most important goal of the RCS structural analysis is to prove the safety of the RCS during normal operation or postulated events, a widely proven theory having enough conservatism is adopted. The load occurring on the RCS during normal operation is considered as the basic design loading condition throughout whole plant life time. The most typical characteristic of the RCS during normal operation is the thermal expansion of the RCS caused by reactor coolant with high temperature and pressure. Therefore, the exact estimation on the thermal movement of the RCS is needed to get more clear understanding on the thermal movement behavior of the RCS. In this study, the general structural analysis concept and modeling method to evaluate the thermal movement of the RCS under the normal plant operation condition are presented. To discuss the validation of the suggested analysis, analysis results are compared with the measured data which ore referred from the standardized 1000 MWe PWR plant under construction.

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Economic Evaluation of Port Hinterlands Using Real Option -Focusing on the Case Study for Hinterland of Busan New Port- (실물옵션을 이용한 항만배후단지의 가치평가 -부산신항 배후단지 사례분석을 중심으로-)

  • Kim, MyoungHee;Lee, Kihwan
    • Journal of Korea Port Economic Association
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    • v.28 no.3
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    • pp.235-257
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    • 2012
  • Recently the role of ports has been changed to satisfy flexibly needs of demands in global economy. A new concept for ports is not just a place for international trade but an important nodal point in logistics chain. The changing environment like this trend creates a high degree of uncertainty and leaves port managers confused with the question how to respond effectively to dynamic market. The latest studies provide that the port must have a good hinterland to achieve competitive advantages in a logistics chain. Korean Government announced "The Master Development Plan for Port Logistics Parks in Korea" in 2006. This contains the plan of hinterland construction of Busan New Port to achieve the status of logistics hub in Asian market. Previous studies rely solely on traditional DCF(discounted cash flow) analysis for investment of hinterland. However DCF method does not include irreversibility, uncertainty and the choice of timing for investment project. This thesis introduces a ROPM(real options pricing model) which overcomes the limitations of traditional valuation methods. The option valuations in this study utilize the Black-Scholes model, the binomial model and the MonteCarlo simulation to value investment opportunity of a port hinterland. In this thesis, an attempt is made to modify the NPV criterion by incorporating the real options approach, and its application is demonstrated in a hinterland construction investment plan. This research has conducted an empirical analysis by calculating economic value of the investment for a hinterland of Busan New Port.

Evaluation of Yield Load in Pile Load Tests on Driven Piles (관입말뚝에 대한 연직재하시험시 항복하중의 판정법)

  • 홍원표;심기석
    • Geotechnical Engineering
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    • v.5 no.1
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    • pp.7-18
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    • 1989
  • In pile load tests on end bearing piles, generally, it is not possible to continue loading to the ultimate load. Thus, the concept of yield load has been introduced for determining design loads Iron the pile load test records. The conventional rules to determine the yield load were not available for evaluation on pile load test records obtained in 6 fields nearby westers 8r Southern Coasts in Korea. A new rule 9.as presented to determine easily the yield load, based on investigations on the pile load test records. The yield load of piles is determined at the infiection point on semi-logarithmic coordinates (P-logS), in which load is plotted in normal scale and settlement is plotted in logarithmic scale. This method may not only save much costs and times but also present safe luorking circumstances for pile load tests in field. It was found that the yield load represented the elastic limit of the pile load-settlement behalf.iota. The ultimate load, which is given at 25.4mm settlement on pile head, was 1.5 times of the yield load. The allowable long-term and short-term load capacities were, respectively, 50% and 75% of the yield load. The safety factors to get the allowable pile capacity were obtained as 2.0~4.0 for the equations to predict the static pile capacity.

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Advertisement Design Strategy of According to The Brand Life Cycle (브랜드 수명주기에 따른 광고디자인 전략에 관한 연구)

  • Kim, Eun-Young;Lee, Jin-Ryeol
    • Archives of design research
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    • v.18 no.3 s.61
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    • pp.139-148
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    • 2005
  • Generally, the brand has its life cycle as the product has. This life cycle is classified into the stages; introduction, growth, maturity and decline. Since the brand is little different from that of the product's, we can find some differences when it applies to the brand. The most effective method to perceive the brand to the consumers is advertisement, therefore in the advertisement design, it is important to figure out the current stage in the brand life cycle and use the most ideal design strategy in that stage. This study suggests the concept of the brand life cycle and the most effective strategy in each stages of the advertisement design. In the stage of the brand introduction, we apply the 'What is it? Strategy' which introduces the brand itself. In the stage of the growth, 'How does it Differ from? Strategy' is suggested as the advertisement strategy emphasizing the positioning which shows its differential competitive advantages among brands because in this stage there are many competitive brands in the market. In the stage of the maturity, we focus on the 'What does it Convey of? Strategy' stressing on the delivery of brand's value to consumers as consumers they purchase the brand. Finally in the stage of the decline, 'What does it Stand for? Strategy' is suggested in order to emphasize the generation of brand's symbolical meaning rather than to emphasize it's attributes or benefits. Therefore the advertisement design needs the contingent ideal design strategy according to the stages of brand life cycle and the effective brand management through it.

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