• Title/Summary/Keyword: key dimensions

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Reconceptualizing Online Free Spaces: A Case Study of the Sunflower Movement

  • Au, Anson
    • Journal of Contemporary Eastern Asia
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    • v.15 no.2
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    • pp.145-161
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    • 2016
  • Using the Sunflower movement as a case study, this article seeks to articulate a theoretical framework to evaluate online "free spaces" as tools for political mobilization. To this end, this article conducts a thematic and content analysis of 151 posts on the official Facebook page of the Sunflower movement. Key results uncover four thematic functions among posts - expressive, informative, informative-support, and promotional - that overlap, in which the expressive theme prevails, and two thematic topics discussed by posts - damages by protesters and their ideology of freedom. I conclude that: (1) combining the logistic and thematic dimensions of posts enables a specific understanding of an online free space's political viability and anticipates the campaigns it will connect itself to; (2) the networked nature of the Sunflower movement page prompts the reconceptualization of (i) online free spaces as nodes through which various political campaigns and struggles are thematically connected by a political ideology; (ii) inactivity as a strategy where protest capital and followers accumulate to prepare and empower future mobilizations.

A calculation method for finite depth free-surface green function

  • Liu, Yingyi;Iwashita, Hidetsugu;Hu, Changhong
    • International Journal of Naval Architecture and Ocean Engineering
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    • v.7 no.2
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    • pp.375-389
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    • 2015
  • An improved boundary element method is presented for numerical analysis of hydrodynamic behavior of marine structures. A new algorithm for numerical solution of the finite depth free-surface Green function in three dimensions is developed based on multiple series representations. The whole range of the key parameter R/h is divided into four regions, within which different representation is used to achieve fast convergence. The well-known epsilon algorithm is also adopted to accelerate the convergence. The critical convergence criteria for each representation are investigated and provided. The proposed method is validated by several well-documented benchmark problems.

Development of a Simple Manoeuvring Model for Ship-handling Simulator by Analytical Methods (해석적 방법에 의한 선박 시뮬레이터용 단순 조종 모델 개발)

  • Kim, Dong-Jin;Yeo, Dong-Jin;Rhee, Key-Pyo
    • Journal of the Society of Naval Architects of Korea
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    • v.47 no.6
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    • pp.776-781
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    • 2010
  • In the ship-handling simulator, it is important for a ship manoeuvring model to represent the dynamic characteristic of a ship and to be simple for reducing calculation time. Especially, even if principal dimensions of a ship are given in initial design stage, or manoeuvring test data are only given by model or real ship's trials, simulations are often needed to check the manoeuvrability of a ship. In this paper, a simple manoeuvring model based on turning test data of a ship is mathematically developed. And the simulation results are verified by comparing with turning test results of a real ship.

Analysis of International Relation through Analysis of Research Network of Nation and Organization in Micro Battery and Energy Harvesting (마이크로 배터리와 에너지 하비스팅에서 국가 및 기관 연구 네트워크 분석을 통한 국제 관계 분석)

  • Shin, Hyun-Shik;Kwon, Oh-Jin;Park, Jong-Kyu;Shon, Young-Woo;Bae, Young-Chul
    • The Journal of the Korea institute of electronic communication sciences
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    • v.8 no.10
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    • pp.1457-1466
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    • 2013
  • In this paper, we describe the relation of international research of 2 dimensions that deviates the simplification of scientometric analysis focusing on literature. We also present to be able to apply for organization of international relation network centering the micro battery and energy harvesting.

Analysis of Laser Control Effects for Direct Metal Deposition Process

  • Choi Joo-Hyun;Chang Yoon-Sang
    • Journal of Mechanical Science and Technology
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    • v.20 no.10
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    • pp.1680-1690
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    • 2006
  • As a promising and novel manufacturing technology, laser aided direct metal deposition (DMD) process produces near-net-shape functional metal parts directly from 3-D CAD models by repeating laser cladding layer by layer. The key of the build-up mechanism is the effective control of powder delivery and laser power to be irradiated into the melt-pool. A feedback control system using two sets of optical height sensors is designed for monitoring the melt-pool and real-time control of deposition dimension. With the feedback height control system, the dimensions of part can be controlled within designed tolerance maintaining real time control of each layer thickness. Clad nugget shapes reveal that the feedback control can affect the nugget size and morphology of microstructure. The pore/void level can be controlled by utilizing pulsed-mode laser and proper design of deposition tool-path. With the present configuration of the control system, it is believed that more innovation of the DMD process is possible to the deposition of layers in 3-D slice.

Analysis of Radial Force on a Permanent Magnet Synchronous Motor Caused by Dimensional Variation (치수적 결함에 따른 PMSM의 법선방향 힘의 변화에 관한 연구)

  • Lee, Chee-Woo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.59 no.11
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    • pp.1990-1995
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    • 2010
  • Main reasons for causing vibration in a permanent magnet synchronous motor (PMSM) are torque ripple and radial force harmonics, and hence, both of them are undesirable in high-precision machine tools and accurate motion-control actuators. Recent research on radial force is the prediction of major vibration frequencies and modes in terms of motor design such as different winding types and a fractional slot number per pole in the stator. Also, proper phase current has been investigated for minimizing radial force harmonics. During the previous studies, all the motors are assumed to be ideally built up in terms of mechanical dimensions, but it is impossible due to dimensional variation within or outside tolerance in production. Therefore, in this paper, the effect of several key factors on radial force is examined and compared regarding manufacturing imperfection.

Vacuum Technology for EUV Lithography (EUV Lithography를 위한 진공 기술)

  • Joo, Jang Hun
    • Vacuum Magazine
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    • v.1 no.3
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    • pp.14-20
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    • 2014
  • Lithography is widely recognized as one of the key steps in the manufacture of ICs and other devices and/or structures. However, as the dimensions of features made using lithography become smaller, lithography is becoming a more critical factor for enabling miniature IC or other devices and/or structures to be manufactured. As explained above, to make it happen, many other important technologies will have to be addressed. The vacuum technology is one of them and the engineers and experts are paying attention on vacuum technology including vacuum pumps. Especially high Vacuum(HV) and Ultra high vacuum(UHV) are not easy and not simple one. So the manpower who can understand vacuum technology with long experience in vacuum industry is important with basic study.

Micro Patterning of Conductive Line by Micro Droplet Ejection of Nano Metal Ink (나노 금속잉크의 미세 액적 토출을 이용한 마이크로 패터닝)

  • Seo S.H.;Park S.J.;Jung H.C.;Joung J.W.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.10a
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    • pp.689-693
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    • 2005
  • Inkjet printing is a non-contact and direct writing associated with a computer. In the industrial field, there have been many efforts to utilize the inkjet printing as a new way of manufacturing, especially for electronic devices. For the application of inkjet printing to electronic field, one of the key factors is exact realization of designed images into printed patterns. In this work, micro patterning for conducting line has been studied using the piezoelectric print head and silver nano ink. Dimensions of printed images have been predicted in terms of print resolution and diameter of a single dot. The predicted and the measured values showed consistent results. Using the results, the design capability for industrial inkjet printing could be achieved.

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The Study of Reserve Price Reporting Mechanisms: A New Mechanism for Negotiation Support Systems (유보가격 보고 메커니즘을 이용한 협상거래 지원시스템 효율 증대 방안 연구)

  • Shang, Wei;Kwon, Seung-Woo;Lie, Yi-Jun;Yoo, Byung-Joon
    • Asia pacific journal of information systems
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    • v.17 no.1
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    • pp.59-76
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    • 2007
  • Information and Communication Technologies (ICT) changed our everyday business drastically. Business routines have been transformed to online activities. New theories and models were developed for the brand new online environment. For online negotiations, however, the research on new mechanisms is not enough, especially for bilateral distributive negotiations. A reserve price reporting mechanism (RPR) together with its extended version (ERPR) is proposed in this paper. The key improvement of reserve price reporting mechanisms is to let the negotiators report their reserve price to a third-party system before they actually start the negotiation. A prototype of this RPR system is developed and a lab experiment is conducted to test the performance of the two mechanisms compared with traditional direct bargaining (TDB) mechanism. The results of the experiment support that the reserve price report mechanisms proposed are more efficient than the traditional one in several dimensions including social welfare.

Systematic Studies on Some Korean Woody Plants -Anatomy of Lauraceous Stem Woods- (한국산 목본식물에 대한 계통분류학적 연구)

  • Park, Sang Jin
    • Journal of Plant Biology
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    • v.27 no.2
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    • pp.81-94
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    • 1984
  • Anatomical features and cell dimensions of the secondary xylem in the stem of the korean Lauraceas including 6 genera and 12 species were investigated under a light microscope and scanning electron microscope. Key to identification among genera or species was made from the anatomical features and systematic correlation investigated. The stem woods of Lauraceae exhibit the following characters: (1) quite evenly distributed pores (diffuse-porous wood) (2) perforation plates simple or occasionally scalariform in the latewood vessels (3) almostly 2-seriate and heterocellular rays (4) abundant paratracheal-vasicentric parenchyma (5) oil cells. Especially, the appearance of simple perforation plates suggest the Lauraceae to be more or less advanced. It is considered that the series of specialization in the Lauraceae from the perforation plates and the height of rays is as LinderalongrightarrowNeolitsealongrightarrow(Machilus, Litsea, Iozoste)longrightarrowCinnamomum, and Lindera sericea is the most pribitive in the Lauraceae.

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