• Title/Summary/Keyword: Soaring

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Development of Transportation Bio-energy and Its Future (수송용 바이오에너지 개발과 미래)

  • Chung, Jay-H.;Kwon, Gi-Seok;Jang, Han-Su
    • Microbiology and Biotechnology Letters
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    • v.36 no.1
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    • pp.1-5
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    • 2008
  • Negative environmental consequences of fossil fuels and the concerns about their soaring prices have spurred the search for alternative energy sources. While other alternative energies-like solar, wind, geothermal, hydroelectric, and tidal-offer viable options for electricity generation, around 40% of total energy consumption requires liquid fuels like gasoline or diesel fuel. This is where bio-energy/biofuels is especially attractive, where they can serve as a practical alternative to oil. The production of liquid biofuels for transportation will depend upon a stable supply of large amount of inexpensive cellulosic biomass obtained on a sustainable basis. This paper reviewed development status of transportation bio-energy for vehicles, technical barriers to the production of cellulosic ethanol, and the global future of bio-diesel and ethanol production.

Shapes and Aerodynamics of Pterosarus' Wing (Pterosarus 날개 형상 및 공력특성)

  • Cho, Woungjae;Han, Cheolheui
    • Journal of Institute of Convergence Technology
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    • v.7 no.1
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    • pp.23-29
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    • 2017
  • A pterosarus is an ancient flying reptile and the first vertebrate with powered flight. The shapes of the pretosarus'airfoil in the published literature are reconstructed. The aerodynamics of the Pterosarus is obtained using a free software XFOIL. The steady aerodynamics of the Pterosarus' airfoil are investigated focusing on the gliding performance. The numerical results are validated by comparing the computed aerodynamic coefficients with the measured data. The secretes of the Pterosarus' highly camberred airfoil are elucidated by comparing the aerodynamics with that of the birds'.

The Impact of Import Oil Price Increase on the Cost Structure of the Korean Logistics Industry (수입원유가격의 상승이 국내 물류산업의 비용구조에 미치는 영향분석)

  • Yoon, Jae-Ho;Park, Myong-Sup
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.41
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    • pp.169-183
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    • 2009
  • This study has been conducted under the background of the high rocketed international oil price in the mid of the 2008 year. Korean logistics industry then suffered from a harsh labor strike which paralyzed temporarily Korean exports and imports activities mainly due to the rising motor fuel prices. The theme of this study started from the highly practical question: what would be the impact of the soaring crude oil price on the cost structure of the Korean logistics industry? For this practical question this study conducted an input-output analysis utilizing the 2003 year benchmark input-output table, published by the Bank of Korea in 2007.

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The Constitutionality of Individual Mandate under the U.S. Patient Protection and Affordable Care Act of 2010 (미국 의료개혁법의 의료보험 의무가입 제도에 대한 연방대법원의 합헌결정)

  • Lee, Won Bok
    • The Korean Society of Law and Medicine
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    • v.14 no.1
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    • pp.275-302
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    • 2013
  • The Unites States has been plagued with soaring health care costs and an alarmingly large number of uninsured population. The Patient Protection and Affordable Care Act of 2010 ushered in the most sweeping health care reform in the United States since the introduction of Medicare and Medicaid in 1965 to address these issues. The law's requirement for individuals to purchase health insurance (the so-called "individual mandate"), however, not only caused a political stir but also prompted constitutional challenges. Some questioned whether the federal government, lacking general police power, could require its citizens to buy unwanted insurance based on its enumerated powers under the U.S. Constitution. This paper summarizes the decision of the U.S. Supreme Court on the constitutionality of individual mandate, and explores how the decision relates to Korea's own universal health care.

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Chaotic Phenomenon of Vibration signal in Rolling Mill Soaring (회전 기기에서의 카오스 현상에 관한 연구)

  • 배영철;김주완
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2001.05a
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    • pp.374-377
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    • 2001
  • A diagnosis system that provides early warnings regarding machine malfunction is very important for rolling mill so as to avoid great losses resulting from unexpected shutdown of the production line. But it is very difficult to provide early warnings in rolling mill. Because dynamics of rolling mill is non-linear. This paper shows a chaotic behaviour of vibration signal in rolling mill using embedding method. Not only phase plane and Poincare map are implemented but also FFT and histogram of vibration signal in rolling mill is presented by embedding method.

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A study on the methods of datamation of product forms (제품디자인에서의 조형정보의 데이터화를 위한 방법론 연구)

  • 이종석
    • Archives of design research
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    • v.21
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    • pp.89-97
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    • 1997
  • Product designers have both 2dimensional and 3 dimensional images in one mind. But the need of 3 dimensional form data is soaring these days. This study is about methods of effective product design form datamation using processing and reverse design tools regarding to 3 dimensional modeling data and hand made mock-up.

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Automation of Feature Modeling for Fluid Dynamic Bearing Design (FDB 설계의 신뢰성 평가를 위한 형상 Modeling의 자동화)

  • 권정민;김희석;구자춘
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2003.11a
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    • pp.1076-1082
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    • 2003
  • As functional requirement of massive digital information storage devices are on a trend for the higher data transfer rate and lower cost, many different technical efforts are being tested and implemented in the industry. FDB(Fluid Dynamic Soaring) is one of the major breakthroughs in rotor design in terms of TMR budget. Although FDB analysis based on Reynolds' equation is well established and popularly being used for DB design especially for the estimation of bearing stiffness, there are obvious limitations in the approach due to the inherent assumptions. A generalized analysis tool employing the full Navier-Stokes equation and the energy balance is to be beneficial for detailed FDB design In this publication, an efficient geometry modeling method is presented that provides fully integrated inputs for general FVM/FDM codes. By virtue of the flexibility of the presented method, many different detailed FDB design and analysis are carried over with ease.

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A Study on the Rotordynamic Characteristics of the Micro Turbo Generator (터보 방식으로 구동되는 마이크로 파워 시스템의 회전체 동역학적 특성에 관한 연구)

  • Ryu, Keun;Lee, Yong-Bok;Lee, Byoung-Su;Kim, Chang-Ho
    • 유체기계공업학회:학술대회논문집
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    • 2004.12a
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    • pp.109-115
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    • 2004
  • The micro turbo generator is new portable power source based on the Brayton cycle, which consists of a compressor, a turbine, a generator, and a combustion chamber. In this paper, the thermodynamic analysis was performed to find the required condition for hundreds watts power in the micro turbo generator, and also the rotordynamic stability was predicted using the numerical analysis of air foil bearings which support the micro turbo generator. By experimental works, the rotordynamic stability of the micro turbo generator with foil bearings was verified. While various transient dynamic situation, the micro turbo generator had stable performances. From the result, it was demonstrated that air foil bearings could be adapted to the micro turbo generator as a excellent lubrication element.

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- Technology and Tasks of Computer Forensics for Suppressing Computer Crime - (범죄 억제를 위한 컴퓨터 포렌식의 기술과 과제)

  • Lee Sang Rak;Shin Seung Ho;Park Sang Min
    • Journal of the Korea Safety Management & Science
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    • v.6 no.3
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    • pp.327-337
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    • 2004
  • The soaring increase in the number of Internet users combined with the constant computerization of business process has created new opportunities for computer criminals and terrorist. Fortunately, the computer security field is also progressing at a brisk rate. In particular, the field of computer forensics brings new ways of preserving and analyzing evidence related to computer crime. Computer forensics is a new emerging professions of the 21st century. It is the collection, preservation, analysis, and presentation of computer related evidence. For this reason, the various technology of computer forensics is regarded as a powerful tool for suppressing computer crime. Our aims is to introduce the overview of computer forensics technology. We also present the survey results of the state of the art of computer forensics in the domestics and of foreign country.

Simulation of Block Logistics at a Big Shipyard (대형 조선소의 블록 물류 시뮬레이션)

  • Song, Chang-Sub;Kang, Yong-Woo
    • Korean Journal of Computational Design and Engineering
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    • v.14 no.6
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    • pp.374-381
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    • 2009
  • To meet the soaring demand recently, South Korea big shipbuilders are examining two things. One is new investment in plant and equipment. The other is replacement of production resources. Considering plant & equipment investment and replacement of production resources, even if actual production ability would be enough, the real output could be affected by limitation of logistics with lack of analysis. As we set up big shipyard in virtual space, we could perform actual production by using confirm production plan in virtual space. We've analyzed the load of block stock, load of road and load of transporter for logistics effects are followed by production increase. This research is to determine the possible problems of those analyzed results and to present the resolution using the current layout. And then modified yard layout, we reanalyzed previous three logistics effects. This simulation model could help administrator to make rational decision for changing yard layout.