• Title, Summary, Keyword: homogeneous extension

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Development of Web-based User Script Linking System for Three-dimensional Robot Simulation (3차원 로봇 시뮬레이션 환경을 위한 웹 기반의 사용자 스크립트 연동 시스템 개발)

  • Yang, Jeong-Yean
    • The Journal of the Korea Contents Association
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    • v.19 no.2
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    • pp.469-476
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    • 2019
  • Robotic motion is designed by the rotation and the translation of multiple joint coordinates in a three-dimensional space. Joint coordinates are generally modeled by homogeneous transform matrix. However, the complexity of three dimensional motions prefers the visualization methods based on simulation environments in which models and generated motions work properly. Many simulation environments have the limitations of usability and functional extension from platform dependency and interpretation of predefined commands. This paper proposes the web-based three dimensional simulation environment toward high user accessibility. Also, it covers the small size web server that is linked with Python script. The non linearities of robot control apply to verify the computing efficiency, the process management, and the extendability of user scripts.

Performance and Emission Characteristics of a Controlled Auto-Ignition Gasoline Engine according to Variation of the Inlet-Air Temperature (흡입공기온도의 변화에 따른 제어자발화 가솔린기관의 성능 및 배기 특성)

  • Kim, H.S.
    • Journal of the Korea Society For Power System Engineering
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    • v.10 no.1
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    • pp.19-24
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    • 2006
  • This work treats a controlled auto-ignition (CAI) single cylinder gasoline engine, focusing on the extension of operating conditions. The fuel was injected indirectly into electrically heated inlet air flow. In order to keep a homogeneous air-fuel mixing, the fuel injector was water-cooled by a specially designed coolant passage. The engine performance and emission characteristics were investigated under the wide range of operating conditions such as 40 in the air-fuel ratio, 1000 to 1800 rpm in the engine speed, 150 to $180^{\circ}C$ in the inlet-air temperature, and $60^{\circ}$ BTDC in the injection timing. The ultra lean-burn with self-ignition of gasoline fuel by heating inlet air was achieved in a controlled auto-ignition gasoline engine. It could be also achieved that the emission concentrations of carbon monoxide, hydrocarbons and nitrogen oxide significantly reduced by CAI combustion compared with conventional spark ignition engines.

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Cloning of a Gene Encoding Dextranase from Lipomyces starkeyi and its Expression in Pichia pastoris

  • Kang, Hee-Kyoung;Park, Ji-Young;Ahn, Joon-Seob;Kim, Seung-Heuk;Kim, Do-Man
    • Journal of Microbiology and Biotechnology
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    • v.19 no.2
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    • pp.172-177
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    • 2009
  • A gene(lsd1) encoding dextranase from Lipomyces starkeyi KSM22 has been previously cloned, sequenced, and expressed in Saccharomyces cerevisiae. The gene consisting of 1,824 base pairs and encoding a protein of 608 amino acids was then cloned into and secretively expressed in Pichia pastoris under the control of the AOX1 promoter. The dextranase productivity of the P. pastoris transformant(pPIC9K-LSD1, 134,000 U/I) was approximately 4.2-fold higher than that of the S. cerevisiae transformant(pYLSD1, 32,000 U/I) cultured in an 8-1 fermentor. Over 0.63 g/l of active dextranase was secreted into the medium after methanol induction. The dextranase of the P. pastoris transformant, as analyzed by SDS-PAGE and Western blotting, showed only one homogeneous band. This dextranase of the P. pastoris transformant showed a broad band near 73 kDa. Rabbit monoclonal antibodies against a synthetic LSD1 peptide mix also recognized approximately 73 kDa.

Hyperbolic Reaction-Diffusion Equation for a Reversible Brusselator: Solution by a Spectral Method

  • 이일희;김광연;조웅인
    • Bulletin of the Korean Chemical Society
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    • v.20 no.1
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    • pp.35-41
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    • 1999
  • Stability characteristics of hyperbolic reaction-diffusion equations with a reversible Brusselator model are investigated as an extension of the previous work. Intensive stability analysis is performed for three important parameters, Nrd, β and Dx, where Nrd is the reaction-diffusion number which is a measure of hyperbolicity, β is a measure of reversibility of autocatalytic reaction and Dx is a diffusion coefficient of intermediate X. Especially, the dependence on Nrd of stability exhibits some interesting features, such as hyperbolicity in the small Nrd region and parabolicity in the large Nrd region. The hyperbolic reaction-diffusion equations are solved numerically by a spectral method which is modified and adjusted to hyperbolic partial differential equations. The numerical method gives good accuracy and efficiency even in a stiff region in the case of small Nrd, and it can be extended to a two-dimensional system. Four types of solution, spatially homogeneous, spatially oscillatory, spatio-temporally oscillatory and chaotic can be obtained. Entropy productions for reaction are also calculated to get some crucial information related to the bifurcation of the system. At the bifurcation point, entropy production changes discontinuously and it shows that different structures of the system have different modes in the dissipative process required to maintain the structure of the system. But it appears that magnitude of entropy production in each structure give no important information related for states of system itself.

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Biomechanical evaluation of menisectomy using finite element method (유한요소 해석법을 이용한 반월상 연골 절제술의 생체역학적 평가)

  • Bae, Ji-Yong;Park, Jin-Hong;Song, Eun-Kyoo;Park, Sang-Jin;Jeon, In-Su
    • Proceedings of the KSME Conference
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    • pp.1471-1472
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    • 2008
  • To analyze biomechanical effects of various types of menisectomy in the knee joint, the contact area and pressure distribution of intact the knee joint and the operated by various menisectomies were studied by using finite element method their results are compared with each other. In this study, the femur, the tibia, the articular cartilage and the menisci were three dimensionally reconstructed using MR Images of healthy knee joint in full extension of 26 years old male. Also, three dimensional finite element model of the knee joint was constructed including the models of ligaments and tendons on the reconstructed three dimensional model. Bones were considered to be rigid, articular cartilage and menisci were considered as homogeneous, isotropic and linearly elastic materials and ligaments and tendons were modeled as hyperelastic materials. Based on the results, the effects of various types of menisectomy on the knee joints are clearly elucidated.

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An Emission Characteristics of a Controlled Auto-Ignition Gasoline Engine According to Variation of the Injection Timing (분사시기의 변화에 따른 제어자발화 가솔린기관의 배기특성)

  • Kim, H.S.
    • Journal of the Korea Society For Power System Engineering
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    • v.8 no.3
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    • pp.5-10
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    • 2004
  • This work deals with a controlled auto-ignition (CAI) single cylinder gasoline engine, focusing on the extension of operating conditions. In order to keep a homogeneous air-fuel mixing, the fuel injector is water-cooled by a specially designed coolant passage. Investigated are the engine emission characteristics under the wide range of operating conditions such as 40 in the air-fuel ratio, 1000 to 1800 rpm in the engine speed, $150\;to\;180^{\circ}C$ in the inlet-air temperature, and $80^{\circ}$ BTDC to $20^{\circ}$ ATDC in the injection timing. A controlled auto-ignition gasoline engine which has the ultra lean-burn with self-ignition of gasoline fuel can be achieved by heating inlet air. It can be achieved that the emission concentrations of carbon monoxide, hydrocarbons and nitrogen oxides had been significantly reduced by CAI combustion compared with conventional spark ignition engine.

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Performance and Emission Characteristics of a Controlled Auto-Ignition Gasoline Engine according to Variation of the Injection Timing (분사시기의 변화에 따른 제어자발화 가솔린기관의 성능 및 배기특성)

  • Kim, H.S.
    • Journal of the Korea Society For Power System Engineering
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    • v.9 no.1
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    • pp.14-22
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    • 2005
  • This work deals with a controlled auto-ignition (CAI) single cylinder gasoline engine, focusing on the extension of operating conditions. The fuel is injected indirectly into electrically heated inlet air flow. In order to keep a homogeneous air-fuel mixing, the fuel injector is water-cooled by a specially designed coolant passage. Investigated are the engine performance and emission characteristics under the wide range of operating conditions such as 40 in the air-fuel ratio, 1000 to 1800 rpm in the engine speed, $150\;to\;180^{\circ}C$ in the inlet-air temperature, and $80^{\circ}$ BTDC to $20^{\circ}$ ATDC in the injection timing. A controlled auto-ignition gasoline engine can be achieved that the ultra lean-burn with self-ignition of gasoline fuel by heating inlet air. It can be achieved that the emission concentrations of carbon monoxide, hydrocarbons and nitrogen oxide had been significantly reduced by CAI combustion compared with conventional spark ignition engine.

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The Effect of Storage Container Types on Odor Emission and Quality of Piggery Liquid Slurry Fertilizer in the farms (농가의 돈분액비 저장형태가 악취발생과 액비품질에 미치는 영향)

  • Park, Moo-Eon;Kang, An-Seok;Kim, Si-Chang
    • Korean Journal of Soil Science and Fertilizer
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    • v.39 no.3
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    • pp.136-143
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    • 2006
  • The study was carried out to evaluate odor emission during storage time and quality of liquid slurry fertilizer along with three storage container types installed at farmer's fields in Cheorwon. Liquid slurry manure stored in the liquid-circulated or the air-injected tank was very homogeneous in concentration of nutritional elements because of well mixing operation, while nutritional concentration of the manure stored in the non-treated tank was significantly different from top to bottom in the tank, which may bring about partially irregular growth of plant after its application. The potential capacity of offensive odor emitted from liquid slurry manure stored in the liquid-circulated or the air-injected tank was much lower than that emitted from manure stored in the non-treated tank. Low potential capacity may less emit offensive odor after application of piggery liquid slurry on the field. The efficiency in oder to reduce odor emission from liquid manure was slightly higher in the liquid-circulated tank than the air-injected tank

Failure Study for Knee Joint Through 3D FE Modeling Based on MR Images (자기공명영상 기반 3차원 유한요소모델링을 통한 무릎관절의 파손평가)

  • Bae, Ji-Yong;Park, Jin-Hong;Song, Seong-Geun;Park, Sang-Jin;Jeon, In-Su;Song, Eun-Kyoo
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.22 no.6
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    • pp.533-539
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    • 2009
  • In this study, the femur, the tibia, the articular cartilage and the menisci are three dimensionally reconstructed using MR images of healthy knee joint in full extension of 26-year-old male. Three dimensional finite element model of the knee joint is fabricated on the reconstructed model. Also, the FE models of ligaments and tendons are attached on the biologically suitable position of the FE model. Bones, articular cartilages and menisci are considered as homogeneous, isotropic and linear elastic materials, and ligaments and tendons are modeled as truss element and nonlinear elastic springs. The numerical results show the contact pressure and the von Mises stress distribution in the soft tissues such as articular cartilages and menisci which can be regarded as important parameters to estimate the failure of the tissues and the pain of the patients.

Model experiments for the reinforcement method of agricultural reservoirs by overtopping

  • Lee, Young-Hak;Lee, Dal-Won;Heo, Joon;Ryu, Jung-Hyun
    • Korean Journal of Agricultural Science
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    • v.47 no.1
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    • pp.163-171
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    • 2020
  • In this study, a large laboratory model experiment was conducted with the aim of developing an embankment reinforcement method to prevent overtopping, which is the main cause for the failure of agricultural reservoirs. The model experiment was carried out with concrete and asphalt as a permanent reinforcement method and with geomembrane as the emergency method at a deteriorated homogeneous reservoir. Under the non-reinforced conditions, the pattern of the failure appeared in several scour directions from the downstream slope as the overtopping began, and the width and depth of the erosion were magnified as it gradually moved to the dam crest. Under the conditions reinforced with asphalt and concrete, the overtopping was stabilized. In the case of the concrete reinforcement, it was found that the slope of the riprap boundary exhibited downward erosion by the current; thus, it was necessary to construct an extension up to the riprap joint of the upstream and downstream sides to prevent the expansion of the failure. Under the conditions reinforced with the geomembrane sheet, the overtopping was stabilized, and no seepage was found that required the emergency reinforcement method. Asphalt, concrete, and geomembrane sheet reinforcements have been shown to be capable of delaying failure for about 1 hour and 40 minutes compared to the non-reinforcement conditions. The reinforcement method is considered to be a very effective method to prevent disasters during overtopping. The pore water pressure can be used as useful data to predict the risk of failure at an embankment.