• Journal of Aerospace System Engineering
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• v.17 no.6
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• pp.127-132
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• 2023

In this study, designing of a Type 4 pressure vessel using the filament winding method was conducted. In order to prevent leakage in consideration of the design of the hydrogen storage tank, a liner was designed by applying high-density polyethylene (HDPE), and the composite structure was designed by stacking carbon/epoxy in the hoop and helical directions. As a theoretical approach, the angle of the helical fiber and fiber thickness of each hoop and helix were designed. The safety of the design was verified using the commercial software ANSYS.

• Journal of Contemporary Eastern Asia
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• v.22 no.2
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• pp.18-38
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• 2023

This paper examines the Chinese government's response to four epidemic crises, including COVID-19, and analyzes the similarities and differences in these responses. It argues that while the Chinese government learned from previous epidemics and improved its handling of subsequent outbreaks, a significant variation occurred during the COVID-19 pandemic, which had a detrimental impact globally. Existing scholarly research on China's epidemic responses has often been limited in scope, focusing on individual crises and neglecting the central-local government relationship in crisis decision-making. By adopting a comprehensive approach, this paper delves into the nuanced dynamics of China's responses to these epidemics. It highlights the variations in responses, attributing them to the Chinese government's fear of undermined legitimacy and its consideration of its international image. The government's recognition of the importance of public perception and trust, both domestically and globally, has shaped its crisis management strategies. Through a detailed analysis of these factors, this paper contributes to a deeper understanding of the variations observed in China's epidemic responses. It emphasizes the significance of the central-local government relationship and the government's international image in determining its actions during epidemics. Recognizing these factors can provide policymakers and researchers with insights to shape future epidemic response strategies and foster effective global health governance.

• Journal of Contemporary Eastern Asia
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• v.23 no.1
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• pp.35-57
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• 2024

The overarching purpose of this study is to examine the current status of academic public engagement in Vietnam. Data were obtained from a survey with 245 university lecturers, and descriptive statistics were used jointly with Bayesian statistics as tools for analysis. This study reveals that a significant proportion of university lecturers are not involved in public engagement, neither through the public press (66.5%) nor social media (49%). Those who have been active in public engagement use the public press and social networks to communicate science, with the latter being more used than the former. In addition, this study also pointed out that experienced scientists tend to engage with the public press, while early-career researchers often choose social networks. The findings of this study provide implications for higher education policymakers and administrators.

• Journal of Contemporary Eastern Asia
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• v.23 no.1
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• pp.58-82
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• 2024

Former South Korean President Moon Jae-in implemented a project called the Peace Initiative, which prioritized a "peaceful and prosperous Korean Peninsula" as the core national agenda and involved using a peace-based frame instead of a unification approach to address inter-Korean relations from a different perspective. This initiative was evaluated in this study using a revised version of the pyramid model to assess the input-output-result process underlying the project and determine whether it generated results that differed from those achieved by the previous administration. To these ends, this research compared Moon's key presidential speeches with those of his predecessor, Park Geun-hye, as input, news commentaries and responses from major players as output, and the trend of perceptional and attitudinal changes in public opinion as results. Although Moon failed to accomplish significant policy effects on inter-Korean relations because of geopolitical challenges and the transfer of power to the conservative party, the analysis revealed that the input, output, and partial results of inter-Korean dialogue reflect some progress.

• Bulletin of the Korean Mathematical Society
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• v.61 no.2
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• pp.401-419
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• 2024

Let K, H, K_II and H_II be the Gaussian curvature, the mean curvature, the second Gaussian curvature and the second mean curvature of a timelike tubular surface T_γ(α) with the radius γ along a timelike curve α(s) in Minkowski 3-space E³₁. We prove that T_γ(α) must be a (K, H)-Weingarten surface and a (K, H)-linear Weingarten surface. We also show that T_γ(α) is (X, Y)-Weingarten type if and only if its central curve is a circle or a helix, where (X, Y) ∈ {(K, K_II), (K, H_II), (H, K_II), (H, H_II), (K_II , H_II)}. Furthermore, we prove that there exist no timelike tubular surfaces of (X, Y)-linear Weingarten type, (X, Y, Z)-linear Weingarten type and (K, H, K_II, H_II)-linear Weingarten type along a timelike curve in E³₁, where (X, Y, Z) ∈ {(K, H, K_II), (K, H, H_II), (K, K_II, H_II), (H, K_II, H_II)}.

• Progress in Superconductivity and Cryogenics
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• v.26 no.1
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• pp.25-30
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• 2024

High-temperature superconducting rotors offer advantages in terms of output-to-weight ratio and efficiency compared to conventional phase conduction motors or generators. The rotor can be cooled by conduction cooling, which attaches a cryocooler, and by refrigerant circulation, which uses circulating liquid or gas neon, helium and hydrogen. Recent work has focused on environmental issues and on high-temperature superconducting motors cooled with liquid hydrogen that can be combined with fuel cells. However, to ensure smooth supply and return of the cryogenic cooling fluid, a cryogenic rotational coupling between the rotating and stationary parts is necessary. Additionally, the development of a sealing structure to minimize fluid leakage applicable to the coupling is essential. This study describes the design and performance evaluation of a non-contact sealing method, specifically a labyrinth seal, which avoids power loss and heat load caused by friction in contact sealing structures. The seal design incorporates a spiral flow path to reduce leakage using centrifugal force, and computational fluid dynamics (CFD) simulations were conducted to analyze the flow path and rotational speed. A performance evaluation device was configured and employed to evaluate the designed seal. The results of this study will be used to develop a cryogenic rotational coupling with supply and return flow paths for cryogenic applications.

• Polymer(Korea)
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• v.28 no.1
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• pp.92-102
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• 2004

(6-Cholesteryloxycarbonylpentoxypropyl)celluloses (CHPCs) with degree of esterification (DE) ranging from 2.25 to 2.91 were synthesized by reacting hydroxypropyl cellulose with 6-cholesteryloxycarbonylpentanoyl chloride. The acrylic esters of CHPCs (CHPCEs) and their photocrosslinked films with liquidcrystalline order were also synthesized. The thermotropic properties of mesophase for both uncrosslinked and crosslinked samples and the swelling behavior of the crosslinked samples in acetone were investigated. The hydroxypropyl cellulose exhibited an enantiotropic cholesteric phas, while all the uncrosslinked cholesterylbearing samples exhibited a monotropic cholesteric phases; the 6-cholesteryloxycarbonylpentanoyl chloride also showed a monotropic smectic phase. The hydroxypropyl cellulose formed a right-handed helix whose optical pitch (λ$\sub$m/) increases with temperature, whereas all the uncrosslinked derivatives farmed left-handed helices whose λ$\sub$m/'s decreased with temperature. The thermal stability of the mesophase and the magnitude of λ$\sub$m/ at the same temperature for both CHPCs and CHPCEs decreased with increasing DE. All the crosslinked samples, in constrast with CHPCEs, did not display reflection colors but exhibited an anisotropic swelling characteristic of crosslinked gel retaining liquid-crystalline order.

• Journal of Contemporary Eastern Asia
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• v.11 no.2
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• pp.61-75
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• 2012

The historical turbulence between China and Japan started from the First Sino-Japanese War in 1895, and culminated in Japan's invasion of China during World War Two (the Second Sino-Japanese War) between 1937 and 1945. A series of wars caused huge human and material losses in both countries, and both experienced comprehensive transformations during and after the wars. The impact of this historical turbulence is so long-lasting that it still influences both countries' social psyche. Moreover, it continues casting a long shadow upon the current Sino-Japanese relations. The recent turbulence in Sino-Japanese relations partly stems from the historical turbulence. It is much less violent but can also be emotional and worrisome. It started from the early 1980s (the Japanese history textbook controversy in 1982 and the 1985 anti-Japanese student protests in China), and culminated in the anti-Japanese mass demonstrations in multiple Chinese cities in 2005 (Bush 2010; Gries 2005; Reilly 2012; Stockmann 2010; Weiss 2008). In addition to dramatic demonstrations on streets, there are also other forms of movements, such as war reparations movements, in which Chinese war victims demand reparations from the Japanese state and companies (Rose 2005; Xu and Fine 2010; Xu and Pu 2010). Although the tension has existed for many years and surfaced from time to time, the eruption of the nationwide anti-Japanese movements in China in 2005 still shocked many outside observers. Many scholars have tried to explain the anti-Japanese sentiment within current Chinese society that underlies and drives these social movements. Through careful reexamination of the existing literature, this article proposes an explanation for the anti-Japanese sentiment from a perspective that stresses the shifting state-society interaction in China's Japan policy. Specifically, the totalitarian Chinese state's neglect and suppression of genuine social concerns regarding Japan in earlier years, followed by a relatively liberalized state that tolerates societal participation in Sino-Japanese relations, are an importance source of the anti-Japanese sentiment recently observed in China.

• Journal of Contemporary Eastern Asia
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• v.11 no.2
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• pp.47-60
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• 2012

Sino-Japanese relations suffered a great setback during the premiership of Koizumi $Jun'ichir{\bar{o}}$ (2001-2006). Although many factors, such as dispute over the resources of the East China Sea or Japan's anxiety about China's growing military expenditures, are accountable for this situation, it was Koizumi's visits to the Yasukuni Shrine that became a symbol of the controversies between the two countries. The Yasukuni issue triggered a real eruption of profound anti-Japanese feelings among the Chinese people. While commentators in China accused Koizumi of glorifying militarism and whitewashing the atrocities committed by Japanese soldiers during the Second World War, the Japanese public started perceiving China's "exaggerated" reaction as a convenient diplomatic tool used by China to apply pressure on Japan in other bilateral disputes. On the one hand, spontaneous protests against Koizumi's visits to the Yasukuni Shrine constituted a great constraint in China's diplomacy towards Japan, but on the other, they also became an ideal pretext for adopting a tougher stance in Chinese foreign policy. In this paper, I examine different points of view on the Yasukuni issue. After describing the Japanese background of the visits to the controversial shrine, I analyze various interpretations of China's reaction to the problem. Although emotions dominated discourse on the Yasukuni issue both in Japan and China, some pragmatic attempts to use this problem can still be seen. Besides being a side-effect of Koizumi's strong personality, the Yasukuni issue could be used either as a tool of factional struggle in the Chinese Communist Party (CCP) or as an instrument of Chinese foreign policy towards Japan.

• Molecules and Cells
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• v.26 no.2
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• pp.206-211
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• 2008

HI0381 of Haemophilus influenzae was investigated by circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopy. HI0381 is a 153-residue peptidoglycan-associated outer membrane lipoprotein, and a part of the larger Tol/Pal network. Here, we report its backbone $^1H$, $^{15}N$, and $^{13}C$ resonance assignments, and secondary structure predictions. About 97% of all of the $^1HN$, $^{15}N$, $^{13}CO$, $^{13}C{\alpha}$, and $^{13}C{\beta}$ resonances covering 131 non-proline residues of the 134 residue, mature protein, were clarified by sequential and specific assignments. CSI and TALOS analyses revealed that HI0381 contains five ${\alpha}$-helices and five ${\beta}$-strands. To characterize the structure of HI0381, the effects of pH and salt concentration were investigated by CD. In addition, the structural changes occurring when HI0381 was in a membranous environment were investigated by comparing its HSQC spectra and CD data in buffer and in DPC micelles; the results showed that helix ${\alpha}4$ and strand ${\beta}4$ became aligned with the membrane. We conclude that the conformation of HI0381 is affected by the membrane environment, implying that its folded state is directly related to its function.