• 제목/요약/키워드: Proper Size

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Marx 펄스발생기를 응용한 소형 고전압 급준 펄스 발생장치 (Fast Rise Time High Voltage Pulse Generator Applying The Marx Generator)

  • 박승록;정석환;김진규;문재덕
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제50권2호
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    • pp.72-78
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    • 2001
  • A compact size high voltage pulse generator with nanosecond rise time has been designed and investigated experimentally. The inductance of a pulse generator can be reduced by fixing the Marx generator and pulse forming network components into a single cylindrical unit. As a result, nanosecond rise time about $8{\sim}10[ns]$ and pulse width of several hundred [ns] can be obtained from a modified Marx pulse generator. And parametric studies showed that the rise time of the output pulse was depended little on the change of the load resistance and the charging capacitance while, the pulse width of the output pulse was depended greatly upon the change of the load resistance and the charging capacitance. The theoretical showed the possibility to design the laboratory-size pulse generator very fast rising time and a proper pulse width by minimizing stray inductance and varying resistance and capacitance.

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Fast Reference Region Adjustment Using Sizing Factor Generation in Correlation-Based Image Tracking

  • Sung, Si-Hun;Chien, Sung-Il
    • Journal of Electrical Engineering and information Science
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    • 제3권2호
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    • pp.230-238
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    • 1998
  • When size and shape of moving object have been changed, a correlator often accumulates walk-off error. A success of correlation-based tracking largely depends on choosing suitable window size and position and thus transferring the proper reference image to the next frame. For this, we propose the Adaptive Window Algorithm with Four-Direction Sizing Factors (AWA-FSF) for fast adjusting a reference region to enhance reliability of correlation-based image tracking in complex cluttered environments. Since the AWA-FSF is capable of adjusting a reference image size more rapidly and properly, we can minimize the influence of complex background and clutter. In addition, we can finely tune the center point of the reference image repeatedly after main tracking process. Thus we have increased stability and reliability of correlation-based image tracking. We tested performance of the AWA-FSF using 45 real image sequences made of over 3400 images and had the satisfied results for most of them.

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건설에서의 복합재료 : 파괴강도에 대한 치수효과 (COMPOSITES IN CONSTRUCTION : Size/scale Effects in Failure Theory)

  • Kim, Duk-Hyun;Kim, Du-Hwan;Oh, Sang-Sub;Lim, Tae-Ho
    • 한국복합재료학회:학술대회논문집
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    • 한국복합재료학회 2003년도 추계학술발표대회 논문집
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    • pp.187-189
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    • 2003
  • Almost all building/infrastructures made of composite materials are fabricated without proper design. Unlike airplane or automobile parts, prototype test is impossible. One cannot destroy 10 story buildings or 100-meter long bridges. People try to build 100-story buildings or several thousand meter long bridges. In order to realize "composites in construction", the following subjects must be studied in detail, for his design: Concept optimization, Simple method of analysis, Folded plate theory, Size effects in failure, and Critical frequency. Unlike the design procedure with conventional materials, his design should include material design, selection of manufacturing methods, and quality control methods, in addition to the fabrication method.on method.

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Garment Label과 소비자관심에 관한 연구 (Study of Consumer's Interest in Garment Label)

  • 임숙자
    • 한국의류학회지
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    • 제2권2호
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    • pp.227-235
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    • 1978
  • This study was designed to find out consumer's interest in garments label and to help home economists make interest for the further study in relation between producers and consumers as gap bridger. The questionnair method was used to obtained the data which was made by a result of self-administered questionnair. A size of random sample for this research was 364 subjects. The study found the following: (1) Most of consumers are relatively interested in garments label. The most concious age level was woman of fourty. (2) The most interest factor was label of size, price, fiber contents. brand name, directions and precautions on proper use and care. (3) The order of complaining item after washing was change of size, and color, seam pucker. deformation of collar. and button. (4) Most of consumers do not follow the direction when they clean their garments. (5) The respondents seem to be not understand the garment's informative label.

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입자 직경에 따른 물분무수 거동 특성에 관한 수치적 연구 (A Numerical Study of Water Mist Behavior According to Droplet Diameter-Size)

  • 이동찬;정우성;이철규;이덕희;장용준
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년도 춘계학술대회논문집
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    • pp.415-419
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    • 2008
  • In this study, analysis of water mist behavior is performed using numerical simulation. Water mist is characterized by the droplet flow which is one of the multiphase flows and is discrete fluid droplets in continuous air. It is important to choose the proper diameter of droplet-size and the distance between the fire location and the position of water mist because it depends on the buoyancy from fire. Therefore the behavior of water mist with fire should be simulated by FLUENT, a commercial computational fluid dynamics(CFD) program, with Lagrangian discrete phase model. (DPM)

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Effect of Reaction Condition and Solvent on The Size and Morphology of Silica Powder Prepared by An Emulsion Technique

  • Park, Won-Kyu;Kim, Dae-Yong
    • The Korean Journal of Ceramics
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    • 제6권3호
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    • pp.229-235
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    • 2000
  • The spherical silica powder was synthesized by varying the kinds of solvent and mixing energy in emulsion method. The stirring speed varied from 500 to 1000 r.p.m. at 5$0^{\circ}C$ for 2h. Toluene in benzyl groups and a series of alkanes were used as dispersant. The average size of spherical silica particles decreased with increasing the stirring speed and the chain length o solvents used in this work. The average size was controlled in the range of 134~28$\mu\textrm{m}$ by selecting a proper solvent and stirring speed. The optimum processing parameters were described in details.

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직육면체 캐비티의 다중 모드 특성및 표면파 모드 특성 측정 (Measurements of multimode characteristics including surface wave mode in a dielectrically loaded rectangular cavity)

  • 김채영;김윤명;라정웅
    • 전기의세계
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    • 제28권4호
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    • pp.47-52
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    • 1979
  • Total number of resonant modes in a microwave oven cavity may be maximized for a given frequency bandwidth to obtain more uniform power distribution by choosing proper size of the cavity. The total number of modes is calculated for a dielectrically loaded rectangular cavity and its size is suggested here for which the change in the number of modes is less sensitive to the change of dielectric layer thickness and its total number of modes is maximized in a given range of cavity sizes. A prove coupled rectangular cavity is constructed and the total existing modes are measured to see the change of modes depending on the dielectric layer thickness and the cavity size. Surface wave mode existing in the dielectric layer is confirmed by measuring Q and the input impedance of the cavity for this mode, which closely compares with the calculation.

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Preparation of Granule Powders for Thermal Spray Coating by Utilization of Pyrophyllite Minerals

  • Kim, Yong-Hyeon;Shin, Pyung-Woo;Lee, Sang-Jin
    • 한국세라믹학회지
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    • 제53권5호
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    • pp.557-562
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    • 2016
  • Pyrophyllite granule powders for thermal spray coating were successfully prepared through spray drying process. To produce a stable slurry, commercial pyrophyllite powder of $45{\mu}m$ in size was ball-milled for reduction of the size to $2{\sim}3{\mu}m$ and a dispersant was added to control the viscosity. Dense and spherical granules (average granule size : $59{\mu}m$) were prepared under conditions of 12,500 rpm for rotation velocity of the atomizer and 100 cps for slurry viscosity. The granules were then heat treated at $1,200^{\circ}C$ for proper handling strength and flow properties. The final granules had an apparent density of $0.725g/cm^3$ and a flow rate of 2.5 g/sec, which represent excellent properties to be used as the granule powder for thermal spray coatings.

Optimized Neurocontroller for Human Control Skill Transfer

  • Seo, Kap-Ho;Changmok Oh;Lee, Ju-Jang
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.42.3-42
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    • 2001
  • A human is an expert in manipulation. We have acquired skills to perform dexterous operations based upon knowledge and experience attained over a long period of time. It is important in robotics to understand these human skills, and utilize them to bring about better robot control and operation It is hoped that the neurocontroller can be trained and organized by simply presenting human teaching data, which implicate human intention, strategy and expertise. In designing a neurocontroller, we must determine the size of neurocontroller. Improper size may not only incur difficulties in training neural nets, e.g. no convergence, but also cause instability and erratic behavior in machines. Therefore, it is necessary to determine the proper size of neurocontroller for human control transfer. In this paper, a new pruning method is developed, based on the penalty-term methods. This method makes ...

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지역아동센터 급식을 위한 적정 배식량 제안 (Recommendation of Serving Size of the Meal Service of Community Child Centers in Korea)

  • 이상은;심재은;권수연;여윤재;윤지현
    • 대한지역사회영양학회지
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    • 제19권4호
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    • pp.361-371
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    • 2014
  • Objectives: This study was performed to set easily applicable portion sizes by sex and age for children at the Community Child Centers (CCC) in Korea. Methods: Considering the age and gender specific energy level at Target Patterns for children aged 6-18 years, which were suggested as a part of the 2010 Korean Food Guidance System (KFGS), we set three meal sizes. We reclassified the recommended daily servings of Grains, Meat fish eggs beans and Vegetables group at Target Patterns into three meal sizes, and then calculated the recommended serving per meal. Each proposed amount of food per meal was calculated based on serving size of foods commonly eaten at KFGS, which was then allocated to five meal components; rice, soup stew, protein and vegetable side-dishes and Kimchi. Each proposed amount of food per meal was applied to 173 menus' recipes from CANpro 3.0 as main ingredient's amounts. We cooked the 173 menus at the medium size and measured their weights after cooking. Results: Each recommended serving per meal was 0.75, 0.9 and 1.2 for Grains; 1.2, 1.6 and 2.4 for Meat fish eggs beans; 2, 2.4 and 2.8 for Vegetables by meal sizes. Among five meal components, the ratio of small and large to medium size was 1/5 less and 1/3 more for rice and 1/3 less and 1/3 more for soup stew, protein side-dish and Kimchi, respectively. We suggested the same amount for a vegetable side-dish to encourage vegetable intake. Proper portion sizes per meal of medium were rice 190 g, soup stew 210 g (solid ingredients 60 g), protein side-dish 100 g (meat eggs beans) and 70 g (fish), vegetable side-dish 80g and Kimchi 30 g. Conclusions: Proper portion size per meal suggested in this study may be useful at the CCC where dietitians are not available and the approach could be applicable to the other types of meal services.