• Title/Summary/Keyword: NAL

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NUMERICAL ANALYSIS OF THE GUST GENERATOR FOR KARI LOW SPEED WIND TUNNEL (KARI 중형 아음속 풍동용 돌풍 발생기의 수치해석)

  • Park Y. M.;Kwon K. J.;Lee S. W.;Kim T. W.
    • 한국전산유체공학회:학술대회논문집
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    • 2005.10a
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    • pp.275-279
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    • 2005
  • The vortex convection and induced flow field behind the KARI 3m x 4m LSWT gust generator was computed by using Computational Fluid Dynamics. For the accurate simulation of vortex convection, inviscid, laminar, Spalart-Allmars k-e and k-w turbulence models were tested with the NAL gust generator configuration and Spalart-Allmaras turbulence model was selected for the prediction of induced flow field behind the KARI LSWT gust generator. The wind tunnel test was also carried out at KARI LSWT and the results were compared with CFD prediction.

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Current Trends in the Development of Fruit Sorters in Japan

  • Maeda, Hironu;Mizuno, Toshihiro;Kouno, Yoshihide
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1993.10a
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    • pp.1302-1311
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    • 1993
  • In the 90 years or so since the beginning of the 20 th century , orchard growing and agricultural fields in Japan have undergone considerable change in terms of production volume, a seen in Fig. 1. as this change in volume progressed, sorting and packing machines have also grown from the first wooden tools, almost too simple to be called " machines" into sophisticated devices that bring together diverse technologies such as machinery , electronics, and optics. Nowadays, Japan/s agricultural industry is facing unprecedentedly serious labor shortage and the rapid aging of its experienced growers and producers, In additions, Japan has changed from a society oriented towards high-volume production and consumption to a more selective society which prefers smaller volume with the tastes of naturally ripended produce. With consumer trends changing there is a new demand on the part of growers for equipment that can not only measure the external quality of produce , but can measure inte nal quality as well.

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The effect of Mo addion and Magnetic field annealing on the magnetic properties, Magnetostriction and Domain structures of $Fe_{80}B_{12}Si_8$ amorphous alloy. ($Fe_{80}B_{12}Si_8$ 비정질 합금의 자구 및 자왜와 자기적 성질에 미치는 Mo 첨가와 자장 열처리 효과)

  • 고창진;강계명;송진태
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1989.06a
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    • pp.49-51
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    • 1989
  • The effect of Mo elenent and annealing condition on the magnetic properties were investigated in Fe$_{80}$B$_{12}$Si$_{8}$ amorphous alloy. With increasing Mo contents, soft magnetic properties were improved by decreasing coercive force and increasing maximum permeability. These improvements were attributed to the decreasing of magnetostriction by Mo addition. The annealing treatment also improved the soft magnetic properties of (Fe$_{1-x}$ Mo$_{x}$)$_{80}$ B$_{12}$ Si$_{8}$ amorphous alloys. It could be thought that these improvements were ascribed to the relaxation of internal stress.nal stress.ess.

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Relation between the Dipole Orientation and the Degree of Polymerization in Low Viscous Silicone Oils (저점도 실리콘유의 쌍극자 배향과 중합도의 관계)

  • Cho, Kyung-Soon;Kim, Kyung-Hwan;Kim, Wang-Kon;Hong, Jin-Woong
    • Proceedings of the KIEE Conference
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    • 1993.11a
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    • pp.234-236
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    • 1993
  • Dielectric properties of low viscous silicone oils have been investigated as a function of frequency and The increase of polymerization degree was attributed to presence of Si-O-Si bonds and their increased dissociation factor. The application of the Clausius-Mosotti equation on the low viscous silicone oils, it has been previously assumed that the oils were dilute solutions of polar molecules. In the silicone oil the Si-o and O-Si bonds give dipole polarization. Simple relations have been found which dipole moment and activation energy as a function of number of Si atoms in the low viscous silicone oils.

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First Record of the Goby Gymnogobius taranetzi (Perciformes: Gobiidae) from Korea (한국산 망둑어과(농어목) 어류 1미기록종, Gymnogobius taranetzi)

  • Lee, Yong-Joo
    • Korean Journal of Ichthyology
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    • v.23 no.3
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    • pp.246-249
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    • 2011
  • Twenty five specimens (40.8~58.4 mm SL) of Gymnogobius taranetzi (Family Gobiidae) were collected from the estuary of Samcheok-si and Yangyang-gun, Gangwon-do, Korea. This species is distinguished from other Gymnogobius species by oculoscapular canals not extending anteriorly through interorbital space, but replaced by rows of sensory papillae; oculoscapular canal pore C is absent; some yellow bands on body in female with breeding color. The new Korean name "Dong-hae-nal-mang-duk" is proposed for this species.

Fault-Tolerant Middleware for Service Robots (서비스 로봇용 결함 허용 미들웨어)

  • Baek, Bum-Hyeon;Park, Hong-Seong
    • Journal of Institute of Control, Robotics and Systems
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    • v.14 no.4
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    • pp.399-405
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    • 2008
  • Recently, robot technology is actively going on progress to the field of various services such as home care, medical care, entertainment, and etc. Because these service robots are in use nearby person, they need to be operated safely even though hardware and software faults occur. This paper proposes a Fault-Tolerant middleware for a robot system, which has following two characteristics: supporting of heterogeneous network interface and processing of software components and network faults. The Fault-Tolerant middleware consists of a Service Layer(SL), a Network Adaptation Layer(NAL), a Network Interface Layer(NIL), a Operating System ion Layer(OSAL), and a Fault-Tolerant Manager(FTM). Especially, the Fault-Tolerant Manager consists of 4 components: Monitor, Fault Detector, Fault Notifier, and Fault Recover to detect and recover the faults effectively. This paper implements and tests the proposed middleware. Some experiment results show that the proposed Fault-Tolerant middleware is working well.

The Theoretical Concept and Structure of the Image (이미지의 이론적 개념 및 구조 - 의류학의 관점에서 -)

  • 김미영
    • Journal of the Korean Society of Costume
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    • v.31
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    • pp.223-236
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    • 1997
  • The purpose of this study is to set up the concept and the structure of 'the image' theoretically. The study is carried out by the literature research. The image is constituted of several concepts which are as followed: The concept of definition: perception cognition/impression. The concept of target: objective/per-son The concept of content: internal/exter-nal The concept of level :lower/upper Especially levels of image are divided into 3 different levels which are 'simple level' 'complex level 1' 'com-plex level 2' The concept of image is classified into the horizontal and the vertical structure. The concepts of the definition the target the con-tent are included in horizontal strcture and the concept of the level is included in the ver-tical structure.

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Thermal Neutron Activation Analysis of Vanadium and Manganese in Ginseng using 3.76-Minute Vanadium-52 and 2.58 Hour Manganese-56 (人蔘中의 Vanadium 및 Manganese의 熱中性子에 依한 放射化分析)

  • Chong Jin Lee;Chong Kuk Kim;Jin Ha Park
    • Journal of the Korean Chemical Society
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    • v.7 no.1
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    • pp.13-16
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    • 1963
  • Thermal neutron activation analysis was applied to determine the trace amount of Vanadium and Manganese in Buyo and Kumsan Ginseng. These elements have been regarded to have great nutritional value and one of the indispensable factor in the growth of ginseng. The TRIGA MARK II Reactor in Atomic Energy Research Institute was used for the neutron source. The samples were irradiated for 10 minutes for Vanadium and for 5 minutes for Manganese at the neutron flux of about $1.28{\times}10^{12}n/cm^2/sec$ and the RCL 256 Channel Pulse-Height Analyzer connected with $2"{\times}2"$ Nal(Tl) was used for activity determination. The amounts were about 0.02 ppm for Vanadium and 20 ppm for Manganese, and it was also found that the amounts of the elements were slightly different depending on the kinds of ginsengs.

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A Study on Position Control of an Electro-Hydraulic Servo System Using High Speed On-Off Valves (고속전자밸브를 사용한 전기유압서보시스템의 위치제어에 관한 연구)

  • 허준영
    • Journal of Advanced Marine Engineering and Technology
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    • v.23 no.3
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    • pp.369-378
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    • 1999
  • This paper presents position control of an electro-hydraulic servo system whoch is operated by four 2-2way high speed on-off valves with either PWM PID control method or sliding mode control method, The advantages of using high speed on-off valves instead of electo-hydraulic servo valves or electro-hydraulic proportional valves are low price robustness for oil contamination and direct control without a D/A converter. The system consists of load cylinder inertia car potentiometer and external load cylinder. The experiments were carried out under several conditions and the results were compared. As a result the sliding mode method has shown good control performance and the robust and stable positioning of the elector-hydraulic servo system can be achieved accurately.

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Pseudomonas sp. strain DJ77 균주에서 extradiol dioxygenase 를 암호화하고 있는 phnE 유전자의 염기배열

  • 김영창;신명수;윤길상;박영순;김욱현
    • Korean Journal of Microbiology
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    • v.30 no.1
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    • pp.8-14
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    • 1992
  • Nucleotide Sequence of phnE Gene Encoding Extradiol Dioxygenase fromPseudomonas sp. Strain DJ77Kim, Young-Chang'.", Myeong-Su Shin1, Kil-Sang Younl, Young-Soon Park1, andUg-Hyeon Kim'.' (Department of Microbiology, C'hungbuk National University.Cheongju 360-763, KOREA. and 'Research Center for Molecular Microbiology,Seoul National University)nal University)

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