• Title/Summary/Keyword: drawing behavior

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A study on the convergence of library and information science and communication studies (문헌정보학과 커뮤니케이션연구의 집중(convergence)에 관한 고찰)

  • 윤혜영
    • Journal of Korean Library and Information Science Society
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    • v.20
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    • pp.471-495
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    • 1993
  • This paper focuses on issues in the convergence of library and information science and communication studies. Common research topics in both fields include scholarly communication, knowledge gaps, invisible colleges, diffusion of innovations, human interaction with communication technologies, information-seeking behavior, information theory, and the information society. To consider these two disciplines in this broader context, this paper compares these two discipline's paradigms, suggests four models of convergence, and traces bibliometric studies performed. This study may be of use to those studying scholarly communication or bibliometrics, to faculty constructing curricula in either of the disciplines, to communication and information science scholars seeking new areas of research, and to collection development librarians in drawing the boundaries of these disciplines.

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Empirical Analysis of the Effect of 3D Avatars on Consumer's Online Purchasing Behavior in Virtual World : Emphasis on Trust Transference (가상세계에서 3차원 아바타 판매원이 소비자 온라인 구매 행위에 미치는 영향에 관한 실증연구 : 신뢰전이를 중심으로)

  • Chae, Seong-Wook;Lee, Kun-Chang;Lee, Keun-Young
    • Knowledge Management Research
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    • v.10 no.3
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    • pp.153-173
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    • 2009
  • Virtual world typically characterized by Second Life (www.secondlife.com) has been successfully drawing a great deal of potential users all around the world. Attention towards 3D avartars has been increasing exponentially especially in the electronic commerce world. 3D avatars have firm position in the virtual world. This study is launched to explore this research void in which trust transference from 3D-avatars-sales representative to customers purchase intention will be especially analyzed on. To perform experiments, a research model was built in a form of path analysis. Two types of 3D avatars were designed and implemented-at-tractive type and professional type. Questionnaire survey was adopted, and empirical analysis results were obtained from the research model. Results reveal that the proposed hypotheses are proven with statistical significance.

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Hydrogen Embrittlement Behavior of High Mn TRIP/TWIP Steels (고 Mn계 TRIP/TWIP 강의 수소취성 거동)

  • Jung, Jong-Ku;Lee, Oh-Yeon;Park, Young-Koo;Kim, Dong-Eun;Jin, Kwang-Geun
    • Korean Journal of Materials Research
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    • v.18 no.7
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    • pp.394-399
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    • 2008
  • The hydrogen embrittlement susceptibility of high strength TRIP/TWIP steels with the tensile strength of 600Mpa to 900Mpa grade was investigated using cathodically hydrogen charged specimens. TWIP steels with full austenite structure show a lower hydrogen content than do TRIP steels. The uniform distribution of strong traps throughout the matrix in the form of austenite is considered beneficial to reduce the hydrogen embrittlement susceptibility of TWIP steels. Moreover, an austenite structure with very fine deformation twins formed during straining could also improve the ductility and reduce notch sensitivity. In Ubend and deep drawing cup tests, TWIP steels show a good resistance to hydrogen embrittlement compared with TRIP steels.

Spring Back in Amorphous Sheet Forming at High Temperature (아몰퍼스 고온 판재성형시 스프링백)

  • Lee Y-S
    • Transactions of Materials Processing
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    • v.14 no.9 s.81
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    • pp.751-755
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    • 2005
  • This paper is concerned with spring back after sheet forming of bulk amorphous alloys in the super cooled liquid state. The temperature-dependence and strain-rate dependence of Newtonian/non-Newtonian viscosities as well as the stress overshoot/undershoot behavior of amorphous alloys are reflected in the thermo-mechanical Finite Element simulations. Hemispherical deep drawing operations are simulated for various forming conditions such as punch velocity, die comer radius, friction, blank holder force, clearance and initial funning temperature. Here, spring back by an instantaneous elastic unloading was followed by thermal deformation during cooling, and two modes of spring back are examined in detail. It could be concluded that the superior sheet formability of an amorphous alloy can be obtained by taking the proper forming conditions for loading/unloading.

The Preparation of Alumina Fiber by Sol-Gel Method (I) Rheological Properties (졸겔법에 의한 알루미나 섬유의 제조 (I) 유동학적 특성분석)

  • 최용수;이종혁;이해욱;김창은
    • Journal of the Korean Ceramic Society
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    • v.32 no.1
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    • pp.17-24
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    • 1995
  • The TEA complex polymeric sol was prepared by the alkoxide sol-gel method. The purpsoe of this experiment was to vefity the particle shape in the sol from the investigation of the rheological properties. TEA retarded hydrolysis rate by the reaction with alkoxide enough to make a stable transparent sol in the wide range of composition. From the results of the viscosity change with time, the optimum mole ratio for spinning was selected as 0.5 mole of TEA, 3 mole of H2O and the optimum viscosity was 104 cPs. The rheological behavior of the sol showed that the particle shape in the sol was linear, which was adequate for fiber drawing.

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An analysis of the wrinkling initiation in sheet metal forming using bifurcation theory (분기좌굴이론을 이용한 박판성형공정에서의 주름발생해석)

  • 김종봉;양동렬;윤정환
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1998.03a
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    • pp.28-31
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    • 1998
  • Wrinkling is one of the major defects in sheet metal products and may be also attributable to the wear of the tool. The initiation and growth of the wrinkles are influenced by many factors such as stress state, mechanical properites of the sheet material, geometry of the body, and contact condition. It is difficult to analyze the wrinkling initiation and growth considering the factors because the effects of the factors are very complex and the wrinkling behavior may show wide variation for small deviation of the factors. In this study, the bifurcation theory is introduced for the finite element analysis of wrinkling initiation and growth, All the above mentioned factors are conveniently considered by finite element method. The finite element formulation is based on the incremental deformation theory and elastic-plastic material modeling. The finite element analysis is carried out using the continuum-based resultant shell elements considering the planar anisotropy of the sheet metal. The proposed method is verified by employing to column buckling problem. And then, the initiation and growth of wrinkling in deep drawing of cylindrical cup are analyzed.

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Study on Phenomenological and Crystal Plasticity Models to Predict Anisotropic Behaviors for Aluminum Alloy Sheets (알루미늄 판재의 이방성거동 예측을 위한 현상학적 모델과 결정소성학적 모델의 비교연구)

  • Chung, W.J.;Yoon, J.W.;Cuitino, A.
    • Transactions of Materials Processing
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    • v.15 no.8 s.89
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    • pp.574-580
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    • 2006
  • Anisotropy has an important effect on the strain distribution in aluminum alloy sheet forming, and it is closely related to the thinning and formability of sheet metals. Thus, the anisotropy of the material should be properly considered for the realistic analyses of aluminum sheet forming processes. For this, anisotropy can be approached in two different scales: phenomenological and microstructural (polycrystal) models. Recent anisotropic models (Yld2000-2d; Barlat et al.[1] 2003, Cuitino et al.[2] 1992) were employed in this work. For the simulation using shell element, the method which can impose plane stress condition in the polycrystal model is developed. Lankford values and yield stress ratios are calculated along various directions. As planar anisotropic behavior, a circular cup deep drawing simulation was carried out to compare the phenomenological and microstructure models in terms of earing profile.

Effects of sheet and stamping process variables on side wall curl (딥 드로잉 벽면 만곡에 미치는 소재 및 가공조건의 영향)

  • 박기철;한수식;조태현;황상무
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1998.03a
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    • pp.53-57
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    • 1998
  • In order to investigate the effects of the variables during the stamping process upon the side wall curl behavior, experiments and finite element analyses were done using a 90 degree draw-bending test. The variables considered were the die radius, the forming speed, the restraint force, the lubrication and the sheet grade. The experiments and simulation conditions were selected according to the design of experiment (DOE) approach. The effects of the restraint force, the lubrication and the forming speed were the same for both high strength and mild steels, but the effects of the die radius on the side wall curl were dependent on the magnitude of the die radius and the sheet grade. A straight side wall was observed for both high strength and mild steels when the die radius was about 2∼3 times of the sheet thickness. It was recommended that the restraint force, the forming speed and the friction be increased in order to reduce the side wall curl.

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Utility and Pricing for the Best Effort Internet Services (최선형 인터넷 서비스의 유틸리티와 과금)

  • 李焄;魚潤
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.39 no.6
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    • pp.19-19
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    • 2002
  • In this paper the authors explore the effect of bandwidth sharing to the utility of the customer for the best-effort Internet services and draw a basis for the pricing principle in Internet Protocol networks. Especially, we investigate the behavior of a customer′s utility in case an arbitrary amount of additional bandwidth is allowed to each customer for the elastic traffic, which is the typical example of the non-real time Internet data traffic. After drawing the utility curve, which will be proved to follow the concave curve, we will apply it to the pricing of Internet traffic. Finally, via numerical experiments, we will illustrate the validity and implication of the proposed method.

Utility and Pricing for the Best Effort Internet Services (최선형 인터넷 서비스의 유틸리티와 과금)

  • Lee, Hoon;Uh, Yoon
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.39 no.6
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    • pp.277-284
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    • 2002
  • In this paper the authors explore the effect of bandwidth sharing to the utility of the customer for the best-effort Internet services and draw a basis for the pricing principle in Internet Protocol networks. Especially, we investigate the behavior of a customer's utility in case an arbitrary amount of additional bandwidth is allowed to each customer for the elastic traffic, which is the typical example of the non-real time Internet data traffic. After drawing the utility curve, which will be proved to follow the concave curve, we will apply it to the pricing of Internet traffic. Finally, via numerical experiments, we will illustrate the validity and implication of the proposed method.