• Title/Summary/Keyword: 정당구조

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Computational Numerical Analysis and Experimental Validation of the Response of Reinforced Concrete Structures under Internal Explosion (내부폭발 시 철근콘크리트 구조물 거동에 대한 전산수치해석과 실험적 검증)

  • Ji, Hun;Moon, Sei-Hoon;Chong, Jin-Wung;Sung, Seung-Hun;You, Yang-Sun
    • Journal of the Korea Society for Simulation
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    • v.27 no.1
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    • pp.101-109
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    • 2018
  • Field experiments as well as numerical analyses with finite element analysis codes are two valuable and complemental ways to understand the structural response under explosive blast load. However, there seems to be only limited information available about finite element analysis and experimental validation on the response of structural components under internal explosions. For complementary use of the two ways, the numerical analyses should be validated with field experiments by comparing their results. In this paper, a small-scaled reinforced concrete building with a room is employed for experimental investigations. An amount of TNT is detonated at the center of the room. Pressure at three different sites in the room, displacement of centers of two walls, and damage patterns of four walls are measured and compared to results from numerical analyses. The experimental results are much similar to the numerical analyses results. The finite element analysis code ANSYS AUTODYN is employed to numerically analyze both pressure distribution inside the room and response of walls subjected to blast pressure. The feasibility and validity of the numerical analysis on the reponses of structural components under internal explosions are discussed in terms of structural damage assessment, and evaluated as the same damage in the analysis and the experiments.

Effect of Autumn Seeding Date on the Productivity and Feed Values of Hairy Vetch(Vicia villosa Roth.) Varieties (파종시기가 Hairy Vetch(Vicia villosa Roth) 품종의 생산성 및 사료가치에 미치는 영향)

  • Kim, Sung-Jin;Kim, In-Su;Lee, Ju-Sam
    • Korean Journal of Organic Agriculture
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    • v.15 no.1
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    • pp.59-69
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    • 2007
  • This experiment was conducted to study the spring productivity and feeding value of hairy vetch varieties. We also measured DM yield and feeding value by analyze CP and CF that authors made possible to calculate TDN and RFV. The results can be summarized as follows; Dry matter yield were increased earlier autumn seeding date and later cut in spring. Differences of dry matter yield in earlier cut in spring was high in order of Ostsaat, Welta, Vv4712, Penn-02, Common and Minnie. Crude protein(CP) yield was increased when earlier autumn seeding date and later cut in spring. Total digestible nutrient(TDN) yield of hairy vetch varieties was decreased when later autumn seeding date, and was increased when later cut in spring. TDN yield was highest in Ostsaat and Welta varieties had highest dry matter yield. Acid detergent fiber(ADF) content was decreased when later autumn seeding date and was increased when later cut in spring. Neutral detergent fiber(NDF) content was decreased when later autumn seeding date. Average values for relative feed value(RFV) were 157% and 132% in both cut. It shows that a high feed value in all of hairy vetch varieties. Above all, the results presented that the optimal seeding date for cultivating hairy vetch in the central region of Korea is between the 10th to the 20th of September. Because Ostsaat and Welta had significantly high dry matter yield we expected Ostsaat and Welta have a higher wintering ability.

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The Photography as Technological Aesthetics (데크놀로지 미학으로서의 사진)

  • Jin, Dong-Sun
    • Journal of Science of Art and Design
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    • v.11
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    • pp.221-249
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    • 2007
  • Today, photography is facing to the crisis of identity and dilemma of ontology from the digital imaging process in the new technology form. It is very important points to say rethinking of the traditional photographic medium, that has changed the way we view the world and ourselves is perhaps an understatement and that photography has transformed our essential understanding of reality. Now, no longer are photographic images regarded as the true automatic recording, innocent evidence and the mirror to the reality. Rather, photography constructs the world for our entertainment, helping to create the comforting illusions by which we live. The recognition that photographs are not constructions and reflections of reality, is the basis for the actual presence within the contemporary photographic world. It is shock. This thesis's aim is to look for the problems of photographic identity and ontological crisis that is controlling and regulating digital photographic imagery, allowing the reproduction of the electronic simulations era. Photography loses its special aesthetic status and becomes no more true information and, exclusively evidence by traditional film and paper that appeared both as a technological accuracy and as a medium-specific aesthetic. The result, photography is facing two crises, one is the photographic ontology(the introduction of computerized digital images) and the other is photographic epistemology(having to do broader changes in ethics, knowledge and culture). Taken together, these crises apparently threaten us with the death of photography, with the 'end' of photography and the culture it sustains. The thesis's meaning is to look into the dilemma of photography's ontology and epistemology, especially, automatical index and digital codes from its origin, meaning, and identity as the technological medium. Thus, in particular, thesis focuses on the analog imagery presence, from the nature in the material world, and the digital imagery presence from the cultural situations in our society. And also thesis's aim is to examine the main issues of the history of photography has been concentrated on the ontological arguments since the discovery of photography in 1839. Photography has never been only one static technology form. Rather, its nearly two centuries of technological development have been marked by numerous, competing of technological innovation and self revolution from the dual aspects. This thesis examines recent account of photography by the analysis of the medium's concept, meaning, identity between film base image and digital base image from the aspects of photographic ontology and epistemology. Thus, the structure of thesis is fairy straightforward to examine what appear to be two opposing view of photographic conditions and ontological situations. Thesis' view contrasts that figure out the value of photography according to its fundamental characteristic as a medium. Also, it seeks a possible solution to the dilemma of photographic ontology through the medium's origin from the early years of the nineteenth century to the raising questions about the different meaning(analog/digital) of photography, now. Finally, this thesis emphasizes and concludes that the photographic ontological crisis reflects to the paradoxical dynamic structure, that unsolved the origins of the medium, itself. Moreover, even photography is not single identity of the photographic ontology, and also can not be understood as having a static identity or singular status from the dynamic field of technologies, practices, and images.

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An Improved Load Control Strategy for the Ultimate Analysis of Curved Prestressed Concrete Cable-Stayed Bridge (곡선 PSC 사장교의 극한해석을 위한 개선된 하중제어법)

  • Choi, Kyu-Chon;Lee, Jae-Seok
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.22 no.1
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    • pp.1-13
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    • 2009
  • A study for the nonlinear solution strategies to predict the ultimate behavior of a curved PSC cable-stayed bridge with complex geometry and highly nonlinear characteristics is presented. The load and displacement control strategies are used and found to be stable for the nonlinear solution of the PSC bridge up to the moderately excessive load. The ultimate analysis of curved PSC cable-stayed bridge using these solution strategies is not converged due to the propagation of the cracks in the wide range of the concrete elements and excessive variation of the stresses in the concrete elements and cables according to the complex geometry. The load control strategy using scale-down of the unbalanced loads is proposed as an alternative method for the case that the solution is not converged due to the severe nonlinearities involved in the PSC structures like a curved PSC cable-stayed bridge. Through the ultimate analysis of the PSC girder, the accuracy and the stability of the proposed solution strategies are evaluated. Finally, the numerical results for the ultimate analysis of the curved PSC cable-stayed bridge using scale-down of the unbalanced loads are compared with those obtained from other investigator. The validity of the proposed nonlinear solution strategy is demonstrated fairly well.

The New Urbanization Process and Changing Urban Space of Daejon in the 1990s (1990년대 대전의 신도시화 과정과 도시 공간의 변화)

  • Choi, Gum-Ae;Kang, Hyun-Soo;Choi, Byung-Doo
    • Journal of the Korean association of regional geographers
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    • v.10 no.1
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    • pp.67-82
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    • 2004
  • There is a general agreement that the global social-economic system is undergoing fundamental changes, which can be explained in terms of the transformation of production system from the Fordism to Post-Fordism since the 1980s. These fundamental changes have resulted in the 'new urbanization' process in the most of large cities in the developed countries. The aim of this paper is to identify the 'new urbanization' process in a large city in Korea that is, Daejon. For the propose, this paper tries to examine and conceptualize empirically the changes of economic, political, social-cultural, and spatial aspects of Daejon metropolis in the respect of 'new urbanization'. The major findings of this essay are summarized as follows. First of all, Daejon economy has experienced new changes, that is the development of service economy and high tech industry. But the old industry still remain important in the urban economy. Secondly, in the political aspect, new civil movements flourish in the city, while the political power of Jaminlyeon, a pro-conservative and narrow-regionalism party, once dominated this region, has decreased its influence. Thirdly. the original CBD of Daejon has been declined while new (sub-)CBBs have emerging in Daejon spatial structures. In conclusion, we can find some clues of the new urbanization process in Daejon, but this process is still quite slow and somewhat different from those of large cities of the developed countries.

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Nonlinear Analysis of PSC Girders with External Tendons (외부강선으로 긴장된 PSC 거더의 비선형 해석)

  • Choi, Kyu-Chon;Lee, Jae-Seok
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.23 no.3
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    • pp.303-314
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    • 2010
  • A study for the nonlinear analysis method of prestressed concrete(PSC) girders with external tendons is presented. The PSC girders with external tendons show the complex nonlinear behavior due to the slip of external tendons at deviator and the change of eccentricity between the girders and external tendons. The external tendon between anchorage-deviator or deviator-deviator is modeled as an assemblage of the curved elements. The slip effect of the external tendon at deviator is taken into account using the force equilibrium relationship between the friction force and the driving force at each deviator. The finite element model and analysis method of the external tendon suggested herein are integrated in the nonlinear analysis program of segmentally erected PSC frames developed by the authors. The proposed analysis method is verified through the comparison of the analysis and experimental results obtained from other investigators. From the ultimate analysis results of PSC beams with external tendons having different number of deviators, the yielding and ultimate loads of PSC beams found to be increased as the number of deviators are increased. In addition, the ultimate capacity of the PSC beam increases according to the increase of friction coefficient between deviator and external tendon, whereas found to decease over the certain value of friction due to the effect of the moment transmitted to the member by the friction force exerted from the external tendon.

Gender Mechanism of Korean Welfare Politics: Gender Difference in Attitudes and Mediating Effects of Welfare Statuses (한국 복지정치의 젠더메커니즘: 태도의 성별차이와 복지지위 매개효과를 중심으로)

  • Kim, Eun-Ji;Ahn, Sang-Hoon
    • Korean Journal of Social Welfare Studies
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    • v.41 no.2
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    • pp.309-334
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    • 2010
  • This study explores gender mechanism of welfare politics in Korea from the perspective of welfare status theory. In the simplistic analysis, it is found that there is no gender difference in welfare attitudes. In the more sophisticated analysis of welfare-status-beased SEM, however, it is found that Korean welfare politics is to be understood in terms of gender-related politics. Three major findings of this study are as follows. Firstly, Korean women possess less pro-welfare attitudes in terms of the status of welfare beneficiary. This is due to the visible gender segregation in the Korean labor market on the one hand and due to the centrality of social insurance programs in the structure of Korean public welfare system on the other hand. Secondly, Korean women have relatively higher level of pro-welfare attitude when it comes to the status of welfare service provider. Thirdly, Korean women tend to be more supportive to pro-welfare parties as they have less chance to be a higher taxpayer. Based on the above mentioned findings, this study concludes that it is possible to make Korean women be more pro-welfare if the Korean welfare state expands more social services that tend to meet urgent needs of women.

Cost-Benefit Analysis of Risk Assessment Regulation in Manufacturing Industries (유해위험방지계획서 적용에 따른 업종별 비용편익효과 분석)

  • Lee, Gibaek;Baek, Jong-Bae
    • Journal of the Korean Institute of Gas
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    • v.16 no.6
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    • pp.80-86
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    • 2012
  • From 1982, the Korean Ministry of Employment and Labor has executed the risk assessment regulation for manufacturing industries. When a manufacturing company install, transfer, or modify the major facilities, the program inspects and verifies safety of the working place to ensure safety against risks. This study performed cost-benefit analysis of the program for the eight industrial categories that were free from the program. The cost-benefit analysis is the basic method to estimate the effect of the policy execution, and used to justify the policy effectiveness. As a result, there is the biggest benefit in the manufacture of basic metal products and then motor vehicles, trailers and semitrailers, other manufacturing, other machinery and equipment, wood products of wood and cork, rubber and plastic products, food products, furniture in order. Thus the hazard prevention program should be applied into the 8 industrial categories in order to strengthen national competitiveness, protect labors's safety, reduce the social cost and improve the welfare.

Analysis of Policy Streams and Policy Narratives for Paradigm Change in Service Development Policy in Korea (서비스발전정책의 정책흐름 및 정책담화 분석과 서비스 패러다임으로의 변화)

  • Jeong, Kioh
    • Journal of Service Research and Studies
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    • v.7 no.1
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    • pp.1-14
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    • 2017
  • Despite that Korea has tried 50 years of service development policies, the result has been unsatisfactory. Borrowing the policy stream model of policy change and narrative policy framework one tried to explain the weaknesses of the policy process for the service development policies. Before 2000 lacking knowledge resulted in poor policy narratives while after 2000 despite sufficient knowledge base and well articulated narratives policy window would not open. Adversarial politics under conservative party caused the window to be closed. One suggests that paradigm shift in value and world view treats is necessary to overcome the policy failures in service development policy. According these analyses one expects a new initiative of policy narrative construction.

The Information Effect of Medical Examination on Individual Health Promotion Behaviors: Evidence from Korea (개인의 건강증진행위에 대한 건강검진의 정보효과: 한국의 경우를 중심으로)

  • Lim, Jae Young
    • KDI Journal of Economic Policy
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    • v.33 no.1
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    • pp.73-91
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    • 2011
  • This paper demonstrates empirically that individuals who monitor indicators of their current cardiovascular health status by undergoing medical examinations are more likely to invest in their own health than those who do not observe such monitoring protocols. Using data from the 2001 National Health and Nutrition Examination Survey of Korea in a structural econometric model, this paper attempts to control the endogeneity problem inherent to the individual decision as to whether to undergo medical examinations, and provides estimation results showing that increased individual health awareness via medical examinations exerts a statistically significant positive effect on health investments. From the policy perspective, the estimation results of this paper may provide a rationale supporting the health policy of free provision of health examination services to the insured via National Health Insurance.

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