• Structural Engineering and Mechanics
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• v.60 no.6
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• pp.1039-1061
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• 2016

Based on Vlasov's torsional theory of open thin-walled members and the nonlinear constitutive relations of materials, a nonlinear analysis model to predict response of open thin-walled RC members subjected to pure torsion is proposed in the current study. The variation of the circulatory torsional stiffness and warping torsional stiffness over the entire loading process and the impact of warping shear deformation on the torsion-induced rotation of the member are considered in the formulation. The torque equilibrium differential equation is then solved by Runge-Kutta method. The proposed nonlinear model is then applied to predict the behavior of five U-shaped thin-walled RC members under pure torsion. Four of them were tested in an earlier experimental study by the authors and the testing data of the fifth one were reported in an existing literature. Results show that the analytical predictions based on the proposed model agree well with the experimental data of all five specimens. This clearly shows the validity of the proposed nonlinear model analyzing behavior of U-shaped thin-walled RC members under pure torsion.

• Nuclear Engineering and Technology
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• v.51 no.4
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• pp.1008-1016
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• 2019

In the SG (steam generator) of PWR (pressurized water reactor) for a nuclear plant, hundreds of U-shaped tubes are used for the heat exchanger system. They interact with primary pressurized cooling water flow, generating flow-induced vibration in the secondary flow region. A simplified U-tube model is proposed in this study to apply for experiment and its counterpart computation. Using the commercial code, ANSYS-CFX, we first verified the Moody chart, comparing the straight pipe theory with the results derived from CFD (computational fluid dynamics) analysis. Considering the virtual mass of fluid, we computed the major modes with the low natural frequencies through the comparison with impact hammer test, and then investigated the effect of pump flow in the frequency domain using FFT (fast Fourier transform) analysis of the experimental data. Using two-way fluid-structure interaction module in the CFD code, we studied the influence on mean flow rate to generate the displacement data. A feasible CFD method has been setup in this research that could be applied potentially in the field of nuclear thermal-hydraulics.

• The Journal of Art Theory & Practice
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• no.4
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• pp.7-32
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• 2006

This study is about the cultural policy related to fine art under the U. S. Military Government in Korea(USAMGIK), from September 8, 1945, to August 15, 1948. Drawing on the previous studies of Korean art history in the 'Liberation Period', this study especially concentrates on intention, attitude and activities of the USAMGIK. Particularly the historical documents, stored at the National Archives at the College Park, Maryland, U.S.A., were valuable to do research on the cultural policy of USAMGIK. The cultural policy was subordinated to the political objectives of occupation that can be summarized to building a stronghold of anti-communism in South Korea. Under the U.S. Military government control, cultural matters were assigned to the Cultural Section, the Bureau of Education, which later turns into the Bureau of Culture, the Department of Education. The Bureau of Culture dealt with matters of the ancient Korean art treasures and of the Korean contemporary art. USAMGIK reopened the Korean National Museum which had been closed by the Japanese since the World War II period. After that, U.S. Department of State sent arts & monuments specialists to South Korea for investigating ancient Korean art and culture. Although some of the destructed art treasures were restored during the occupation, th ere were many negative cases including intentional destruction of historic sites or loot of art treasures by U.S. army. In contrast to their interest in the Korean antiquities, USAMGIK payed little attention to promoting the Korean contemporary artists and their arts. USAMGIK distrusted and suppressed the artists of leftism, while they kept good relations with the pro-American artists and the right-wing artists. In conclusion, the visual-cultural policy of USAMGK was mainly planned and carried out in order to preserve the national interest of the United States. This period produced long-term effects on the fine art and visual culture of South Korea, in terms of institution, policy, and reorganization of art community based on anti-cummunism.

• Convergence Security Journal
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• v.17 no.3
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• pp.83-93
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• 2017

The U.S.-China Relations could be analyzed two perspectives and their basis under major international p olitics theory-power transition with conditions: (1) North Korean's nuclear puzzle, (2) THAAD in the Kor ean Peninsula and (3) the U.S.-ROK Alliance. One perspective is the global order dominates the regional order, and then stable regional order comes out. The other is the regional order dominates the global ord er, and China wages a regional hegemonic conflict against the United States. Consequently, America's o verwhelming leadership in North Korean's nuclear, THAAD and U.S.-ROK Alliance as national power is expected to endure. But China also has expected empowerment and cooperation for the peace and stabilit y on the Korean Peninsula military problems. In this perspective, South Korea needs to pay attention to the changing power distribution and competition between the U.S. and China and needs to strengthen a balancing and harmonious diplomatic strategy, so called 'see-saw diplomacy'.

• Korean Management Science Review
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• v.30 no.1
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• pp.73-89
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• 2013

This paper develops an investment algorithm based on Markowitz's Portfolio Selection Theory, using historical stock return data, and empirically evaluates the performance of the proposed algorithm in the U.S. and the Hong Kong stock markets. The proposed investment algorithm is empirically tested with the 30 constituents of Dow Jones Industrial Average in the U.S. stock market, and the 30 constituents of Hang Seng Index in the Hong Kong stock market. During the 6-year investment period, starting on the first trading day of 2006 and ending on the last trading day of 2011, growth rates of 12.63% and 23.25% were observed for Dow Jones Industrial Average and Hang Seng Index, respectively, while the proposed investment algorithm achieved substantially higher cumulative returns of 35.7% in the U.S. stock market, and 150.62% in the Hong Kong stock market. When compared in terms of Sharpe ratio, Dow Jones Industrial Average and Hang Seng Index achieved 0.075 and 0.155 each, while the proposed investment algorithm showed superior performance, achieving 0.363 and 1.074 in the U.S. and Hong Kong stock markets, respectively. Further, performance in the U.S. stock market is shown to be less sensitive to an investor's risk preference, while aggressive performance goals are shown to achieve relatively higher performance in the Hong Kong stock market. In conclusion, this paper empirically demonstrates that an investment based on a mathematical model using objective historical stock return data for constructing optimal portfolios achieves outstanding performance, in terms of both cumulative returns and Sharpe ratios.

• Phonetics and Speech Sciences
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• v.2 no.2
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• pp.3-16
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• 2010

This study aims at setting the hierarchy of difficulty of the 7 Korean monophthongs for Mongolian learners of Korean according to Prator's theory based on the Contrastive Analysis Hypothesis. In addition to that, it will be shown that the difficulties and errors for Mongolian learners of Korean as a second or foreign language proceed directly from this hierarchy of difficulty. This study began by looking at the speeches of 60 Mongolians for Mongolian monophthongs; data were investigated and analyzed into formant frequencies F1 and F2 of each vowel. Then, the 7 Korean monophthongs were compared with the resultant Mongolian formant values and are assigned to 3 levels, 'same', 'similar' or 'different sound'. The findings in assessing the differences of the 8 nearest equivalents of Korean and Mongolian vowels are as follows: First, Korean /a/ and /$\wedge$/ turned out as a 'same sound' with their counterparts, Mongolian /a/ and /ɔ/. Second, Korean /i/, /e/, /o/, /u/ turned out as a 'similar sound' with each their Mongolian counterparts /i/, /e/, /o/, /u/. Third, Korean /ɨ/ which is nearest to Mongolian /i/ in terms of phonetic features seriously differs from it and is thus assigned to 'different sound'. And lastly, Mongolian /$\mho$/ turned out as a 'different sound' with its nearest counterpart, Korean /u/. Based on these findings the hierarchy of difficulty was constructed. Firstly, 4 Korean monophthongs /a/, /$\wedge$/, /i/, /e/ would be Level 0(Transfer); they would be transferred positively from their Mongolian counterparts when Mongolians learn Korean. Secondly, Korean /o/, /u/ would be Level 5(Split); they would require the Mongolian learner to make a new distinction and cause interference in learning the Korean language because Mongolian /o/, /u/ each have 2 similar counterpart sounds; Korean /o, u/, /u, o/. Thirdly, Korean /ɨ/ which is not in the Mongolian vowel system will be Level 4(Overdifferentiation); the new vowel /ɨ/ which bears little similarity to Mongolian /i/, must be learned entirely anew and will cause much difficulty for Mongolian learners in speaking and writing Korean. And lastly, Mongolian /$\mho$/ will be Level 2(Underdifferentiation); it is absent in the Korean language and doesn‘t cause interference in learning Korean as long as Mongolian learners avoid using it.

• The Journal of Korean Philosophical History
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• no.38
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• pp.63-96
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• 2013

$L{\ddot{u}}Zuqian$(呂祖謙) was one of the famous philosophers during the Southern Song period, and is called one of DongNamSanXian(東南三賢) together with ZhuXi(朱熹) and ZhangShi(張?). With his profound knowledge transmitted and uphold by JiaXue(家學), $L{\ddot{u}}Zuqian$(呂祖謙) established his learning system, interacting with scholars of those days. Principally, $L{\ddot{u}}Zuqian$(呂祖謙)'s XinLun(心論) was based on Mengzi(孟子)' theory of LiangXin(良心) and BenXin(本心). $L{\ddot{u}}Zuqian$(呂祖謙) explained the meaning of such a conscience through ChuXin(初心) and Inner NeiXin(內心). According to $L{\ddot{u}}Zuqian$(呂祖謙), ChuXin(初心) arouses when one encounters external things, and this one's intention enables us to make the right judgments over the outside objects. NeiXin(內心) means LiangXin(良心) and BenXin(本心) that recovered the ability of moral awareness. The important significances of $L{\ddot{u}}Zuqian$(呂祖謙)'s XinLun(心論) are XinWai WuDao(心外無道), and XinWaiWuTian(心外無天). Through these, $L{\ddot{u}}Zuqian$(呂祖謙) emphasized that Tian(天), Dao(道), and Li(理) are one. $L{\ddot{u}}Zuqian$(呂祖謙) arranged a meeting of EHuSi(鵝湖寺), and exerted efforts to negotiate the academic differences between ZhuXi(朱熹) and LuJiuyuan(陸九淵). However, compared with LuJiuyuan(陸九淵) who asserted FaMingBenXin(發明本心), $L{\ddot{u}}Zuqian$(呂祖謙) put the emphasis on DaoWenXue(道問學) with self-awareness of conscience. Meanwhile, $L{\ddot{u}}Zuqian$(呂祖謙) valued much of Jing(敬) like ZhuXi(朱熹). But, to $L{\ddot{u}}Zuqian$(呂祖謙), Jing(敬) meant WuJianDuan(無間斷) of ChunYiBuZa(純一不雜) DaoDeXin(道德心), and implied the same as Cheng(誠). $L{\ddot{u}}Zuqian$(呂祖謙) stressed the reading and pursuit of study, however, he also asserted that Li(理) could be understood and realized through self-awareness of one's mind and its reflection, and working without interruption. $L{\ddot{u}}Zuqian$(呂祖謙)'s academic tradition of the XinXueDe XueFeng(心學的 學風), which reveals through compromise and confrontation with ZhuXi(朱熹), can be said that it will have a significant meaning of idealism of dispute in the Southern Song period.

• Steel and Composite Structures
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• v.34 no.4
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• pp.511-524
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• 2020

In this research, a simple four-variable trigonometric integral shear deformation model is proposed for the static behavior of advanced functionally graded (AFG) ceramic-metal plates supported by a two-parameter elastic foundation and subjected to a nonlinear hygro-thermo-mechanical load. The elastic properties, including both the thermal expansion and moisture coefficients of the plate, are also supposed to be varied within thickness direction by following a power law distribution in terms of volume fractions of the components of the material. The interest of the current theory is seen in its kinematics that use only four independent unknowns, while first-order plate theory and other higher-order plate theories require at least five unknowns. The "in-plane displacement field" of the proposed theory utilizes cosine functions in terms of thickness coordinates to calculate out-of-plane shear deformations. The vertical displacement includes flexural and shear components. The elastic foundation is introduced in mathematical modeling as a two-parameter Winkler-Pasternak foundation. The virtual displacement principle is applied to obtain the basic equations and a Navier solution technique is used to determine an analytical solution. The numerical results predicted by the proposed formulation are compared with results already published in the literature to demonstrate the accuracy and efficiency of the proposed theory. The influences of "moisture concentration", temperature, stiffness of foundation, shear deformation, geometric ratios and volume fraction variation on the mechanical behavior of AFG plates are examined and discussed in detail.

• Journal of Korean Philosophical Society
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• v.142
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• pp.295-321
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• 2017

This paper discusses Hegel's concept of Art criticism, focusing on the article "${\ddot{U}}ber$ die Bekehrten" in 16. Vol. of Hegel's Gesammelte Werke. Hegel is a theorist of the system of art, but also an art critic who actively participated in popular art practice. Until now, Hegel has been interpreted mainly as a theorist who usually constitutes the system of art. According to many interpretations, Hegel has been criticized for his theories frame interpretation of the Artwork compulsorily. But in this article we see another aspect of Hegel as an art critic. First, in this article Hegel shows as an art critic how romanticists distort the work with an emphasis on the theory. Hegel argues in his article written in early 1826 that romantic ironic theory does not help at all in understanding the "die Bekehrten" of Laupach. Whereas ironic theory emphasizes the contradiction between character and its action as the essential value of the work, Hegel interprets that the comic is at the center of the work, which lets the unessential sides of the unified character disappear, so that the unity of the character expresses itself. Hegel also interprets that the theory of irony represents the work of art for the scholars, which harms the objectivity of artwork and defends the artwork for the public. Second, Hegel began to apply the achievement of his criticism to his aesthetic lectures. Since 1826 Hegel has focused intensively on discussing two concepts, romantic irony and 'artwork for the public' in his aesthetics lectures. Thus, this article provides a basis for Hegel 's criticism of ironic theory after 1826 and the concept of artwork for the public. In this respect, we can confirm that Hegel has reinforced and extended his theories through his practice of criticism of concrete works of art rather than imposing systematic theories upon art criticism

• Journal of Distribution Science
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• v.13 no.9
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• pp.47-57
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• 2015

Purpose - The aim of this paper is to investigate the explanatory power of the Pecking-order theory (the cost of financing increases with asymmetric information) among Korean retail firms from the perspective of debt capacity. According to the Pecking-order theory, a firm's first preference is to use internal funds for its capital needs, its next preference is the issuance of debt, and its last preference is the issuance of equity; this is due to the information asymmetry problem between existing shareholders and investors. However, prior empirical studies, such as Lemmon and Zender (2010), argue that the entire sample test for the Pecking-order theory could be misleading due to the different levels of debt issuance capability of each of the individual firms; in fact, they confirm that the explanatory power of the Pecking-order theory improves after taking into account the differences in debt capacity of the U.S. firms they examined. This paper implements a case study approach among Korean retail firms to examine the relationship between debt capacity and the explanatory power of the Pecking-order theory in Korea. Research design, data, and methodology - This study uses the sample of public retail firms on the Korea Composite Stock Price Index (KOSPI) from the time period of 1990 to 2013. We gather related financial and accounting statements from the financial information firm WISEfn. Credit rating information is provided by the Korea Investor Service. We employ the models of Lemmon and Zender (2010) and Son and Kim (2013) to measure a firm's debt capacity. Their logit models use the rating dummy variable as a dependent variable and incorporate other firm characteristics as independent variables to estimate debt capacity. To test the Pecking-order theory, we adopt variants of the financing deficit model of Shyam-Sunder and Myers (1999). In the test of the Pecking-order theory, we consider all of the changes in total debt obligations, current debt obligations, and long-term debt obligations. Results - Our main contribution to the literature is our confirmation of the predicted relationship between debt capacity and the explanatory power of the Pecking-order theory among Korean retail firms. The coefficients on financing deficits become greater as a firm's debt capacity improves. This is consistent with the results of Lemmon and Zender (2010). The coefficients on the square of the financing deficits are also negative for the firms in the largest debt capacity group, which is also consistent with the predictions in prior literature. Conclusions - This study takes a case study approach by examining Korean retail firms. We confirm that the Pecking-order theory explains the capital structure of retail firms more appropriately, after taking into account the debt capacity of each firm. This result suggests the importance of debt capacity consideration in the testing of the Pecking-order theory. Our result also implies that there has been a potential underestimation of the explanatory power of the Pecking-order theory in existing studies.