• 제목/요약/키워드: Cross-National study

검색결과 4,503건 처리시간 0.037초

Preparation and Mechanical Properties of Wheat Protein Isolate Films Cross-linked with Resorcinol

  • Chandrasekhar, M.;Prabhakar, M.N.;Song, Jung-Il
    • Composites Research
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    • 제28권2호
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    • pp.40-45
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    • 2015
  • The purpose of the present work was to preparation and study of full biodegradable Eco-friendly bio-composites by using renewable resources. In this study, wheat protein isolate (WPI) films were formed by cross linking with resorcinol through solution casting method for packaging applications. By varying the resorcinol content (10, 20, 30, 40, and 50 wt %), its effect on mechanical properties of the wheat protein isolate film was measured. The addition of 20% resorcinol led to an overall increase in the tensile strength from 5.2 to 18.6 MPa and modulus increase from 780 to 1132 MPa than WPI films. The % elongation was increased from 2.8 to 9.05 when compared to unmodified WPI film. A thermal phase transition of the prepared WPI was assessed by means of DSC. FTIR is evident that the characteristic WPI spectral IR bands shifted on cross-linking with resorcinol.

모바일 인터넷의 사용 가치에 대한 비교 문화적 관점의 실정적 연구 (A Cross-National Study on Mobile Internet Value Structures)

  • 이인성;이연수;김진우;홍세준
    • Journal of Information Technology Applications and Management
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    • 제14권3호
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    • pp.15-48
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    • 2007
  • As the mobile Internet spreads around the globe, a cross-national difference in the use of mobile services has become an important issue. The goal of this study is to propose and verity cross-national differences in the effect of each value-type on user satisfaction with the mobile Internet. We propose an analytic framework of four different types of value and apply this model to the value structures of mobile Internet users in two different countries. Large-scale online surveys were conducted in Korea and Hong Kong simultaneously with the same questionnaire. Results show that the relationships between the value components and user satisfaction varied between the two countries.

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Effect of surface treatment on the mechanical properties of nickel-titanium files with a similar cross-section

  • Kwak, Sang Won;Lee, Joo Yeong;Goo, Hye-Jin;Kim, Hyeon-Cheol
    • Restorative Dentistry and Endodontics
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    • 제42권3호
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    • pp.216-223
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    • 2017
  • Objectives: The aim of this study was to compare the mechanical properties of various nickel-titanium (NiTi) files with similar tapers and cross-sectional areas depending on whether they were surface-treated. Materials and Methods: Three NiTi file systems with a similar convex triangular cross-section and the same ISO #25 tip size were selected for this study: G6 (G6), ProTaper Universal (PTU), and Dia-PT (DPT). To test torsional resistance, 5 mm of the straightened file's tip was fixed between polycarbonate blocks (n = 15/group) and continuous clockwise rotation until fracture was conducted using a customized device. To evaluate cyclic fatigue resistance, files were rotated in an artificial curved canal until fracture in a dynamic mode (n = 15/group). The torsional data were analyzed using 1-way analysis of variance and the Tukey post-hoc comparison test, while the cyclic fatigue data were analyzed using the Mann-Whitney U test at a significance level of 95%. Results: PTU showed significantly greater toughness, followed by DPT and G6 (p < 0.05). G6 showed the lowest resistance in ultimate torsional strength, while it showed a higher fracture angle than the other files (p < 0.05). In the cyclic fatigue test, DPT showed a significantly higher number of cycles to failure than PTU or G6 (p < 0.05). Conclusions: Within the limitations of this study, it can be concluded that the torsional resistance of NiTi files was affected by the cross-sectional area, while the cyclic fatigue resistance of NiTi files was influenced by the surface treatment.

National Cinema as a System of Comparison

  • Park, Nohchool
    • 비교문화연구
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    • 제20권
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    • pp.323-346
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    • 2010
  • This study reviews critical literatures regarding Asian cinema, focusing on studies of Japanese cinema, to show that Western scholarship on non-Western national cinemas have been divided into two approaches: traditionalism and modernism. It argues that such a division is not merely a critical tendency but indicative of the fact that a national cinema is an internally divided construct. To support the point, this study examines Chinese film studies conducted by Chinese film critics and the history of South Korean cinema during the 1970s and 80s. Then, it proposes the hegemony model to theorize the inner structure of national cinema. It finally suggests the possibility of comparative film study that the national cinema thesis may activate.

Internal Flow Analysis on an Open Ducted Cross Flow Turbine with Very Low Head

  • Wei, Qingsheng;Hwang, Yeong-Cheol;Choi, Young-Do
    • 한국유체기계학회 논문집
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    • 제17권5호
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    • pp.67-71
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    • 2014
  • Recently, the cross flow turbine attracts more and more attention for its good performance over a large operating regime at off design point. This study adopts a very low head cross flow turbine that has barely been studied before, and investigates the effect of air layer on the performance of the cross flow turbine. As open duct is applied in this study and free surface model is used between the air layer and water, an engineering definition of efficiency, instead of traditional definition of efficiency, is used. As torque at the runner fluctuates up and down at a reasonable limit, statistical method is used. Pressure and water volume fraction contours are shown to present the characteristics of air-water flow. With constant air suction in the runner chamber, the water level gradually drops below the runner and efficiency of the turbine can be raised by 10 percent. All considered, the effect of air layer on the performance of turbine is considerable.

횡류형 파워 터빈(CPT)에서 솔리디티 영향에 관한 수치해석 연구 (A Numerical Study on Solidity Characteristics of the Cross-flow Power Turbine(CPT))

  • 정광섭;김철호
    • 설비공학논문집
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    • 제22권8호
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    • pp.562-566
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    • 2010
  • Wind energy is one of the most general natural resources in the world. However, as of today, generating electricity out of wind energy is only available from big wind generator, Furthermore, an axial-flow turbine is the only way to produce electricity in the big wind generator. This paper is for the guidance of drawing impact fact about power turbine using cross-flow type transferring wind energy to electricity energy. It will find the ideal value which enables to make cross-flow power turbine(CPT) using computational fluid dynamics(CFD) code. This study tries to analyze the "Solidity" characteristics. We can find out turbine-blade number through CFD. CFD is using "Fluent_ver 6.3.16", and the data from its result will judge fan-blade performance through specific torque and specific power from each "Solidity" model. Based upon the above, we will make cross-flow power turbine of multi-blade centrifugal fan instead of axial-flow type.

Artificial Intelligence and the Virtual Multi-Door ODR Platform for Small Value Cross-Border e-Commerce Disputes

  • Chung, Yongkyun
    • 한국중재학회지:중재연구
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    • 제29권3호
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    • pp.99-119
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    • 2019
  • In recent times, the volume of cross-border e-commerce has witnessed an upward trend and has been accompanied by increased disputes, with cross-border e-commerce being characterized mainly by low value and large volume issues. For this reason, Online Dispute Resolution (ODR) was formed to carry out dispute resolutions in cross-border e-commerce. A virtual multi-door ODR platform for small value, cross-border disputes in e-commerce is then proposed in this paper. For a couple of decades, researchers have tried to employ Artificial Intelligence (AI) to Law. However, it turns out that they were faced with a couple of obstacles to integrate AI to Law since it is highly difficult to program AI to process the common sense of a human being. For example, AI cannot assimilate the affective side of a human being, and it is problematic to integrate a human being's common sense into the AI system. Considering this situation, this study puts forward an ODR model for cross-border e-commerce in the evolutionary perspective.

A Cross-Cultural Study on Student Engagement and Resistance to Critical Literacy in a TESOL MA Classroom

  • Pederson, Rod
    • 비교문화연구
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    • 제36권
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    • pp.175-209
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    • 2014
  • This paper reports on a qualitative examining the cross-cultural reasons for student engagement and resistance to critical literacy in a three week summer TESOL MA course that was part of a Korean/American university faculty exchange program. Of particular interest was the unique diversity of the class which consisted of 13 subjects from 9 different nations. Using student and instructor reflective journals, field notes on classroom observations, and the course terminal paper on student's philosophies of education as research corpora, results of the study revealed that students resisted instruction in critical literacy for ideological and epistemological reasons. Nonetheless, the data also showed that while all students resisted some theories in critical literacy, all students nonetheless engaged the course content in meaningful ways.

잣나무 가도관(假導管)의 벽공(壁孔) 분포(分布)의 변이(變異) (A Study on the Distribution of Pits on the Tracheid in Pinus koraiensis)

  • 이승환;이성재;이원용
    • Journal of the Korean Wood Science and Technology
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    • 제21권4호
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    • pp.60-63
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    • 1993
  • In the present paper, we discribed distributions patterns of pits on the tracheids of Pinus koraiensis. The number of bordered pits on a tracheid is more numerous than that of cross-field pittings. And they appeared different in the number depending on the shape and size of tracheids. Both pit and cross-field pitting on a tracheid is fewer in number near the pith. The number of bordered pits on the tracheid increased rapidly from pith toward cambial zone but that of cross-field pittings increased gradually. The number of bordered pit and corss-field pitting is more frequent in the first-formed tracheid, and the number of bordered pit decreased rapidly from earlywood to latewood but that of corss-field pittings decreased gradually. Bordered pits on a tracheid are more numerous at the end of tracheids and cross-field pittings occur more frequently in the center part of a tracheid.

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The Role of L1 and L2 in an L3-speaking Class

  • Kim, Sun-Young
    • 비교문화연구
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    • 제24권
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    • pp.170-183
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    • 2011
  • This study explored how a Chinese college student who previously had not reached a threshold level of Korean proficiency used L1 (Chinese) and L2 (English) as a tool to socialize into Korean (L3) culture of learning over the course of study. From a perspective of language socialization, this study examined the cross-linguistic influence of L1 and L2 on the L3 acquisition process by tracing an approach to language learning and practices taken by the Chinese student as a case study. Data were collected through three methods; interview protocols, various types of written texts, and observations. The results showed that the student used English as a means to negotiate difficulties and expertise by empowering her L2 exposure during the classroom practices. Her ways of using L2 in oral practices could be characterized as the 'Inverse U-shape' pattern, under which she increased L2 exposure at the early stage of the study and shifted the intermediate language to L3 at the later stage of the study. When it comes to the language use in written practices, the sequence of "L2-L1-L3" use gradually changed to the "L2-L3" sequence over time, signifying the importance of interaction between L2 and L3. However, the use of her native language (L1) in a Korean-speaking classroom was limited to a certain aspect of literacy practices (i.e., vocabulary learning or translation). This study argues for L2 communication channel in cross-cultural classrooms as a key factor to determine sustainable learning growth.