• Title/Summary/Keyword: '곡'계

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The Multimedia Contents Development for Electric Circuit Learning on WWW (웹상에서의 전기제어회로 학습 멀티미디어 컨텐츠개발)

  • 박재규;김인중;강명구;이근무
    • Proceedings of the Korea Multimedia Society Conference
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    • 2001.06a
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    • pp.399-402
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    • 2001
  • 실기 중심의 수업에서 대부분의 학습자들이 반복되는 기능 습득으로 목표점에 도달할 수 있다. 이러한 행동주의적인 학습방법에도 기포적인 이론 즉 인지주의적인 학습이 뒷받침되어야 기능 습득이 효과적으로 된다고 본다. 특히 여기서 다루고자하는 전기회로 실습에서는 기기의 동작원리 및 동작되는 기기에 따라 변화되는 회로의 이해가 학습자에게 무엇보다 중요하다. 그러므로 실습에 사용되는 요소별 회로도의 이해를 돕기 위하여 동영상으로 된 회로분석도가 필요하다. 오늘간 일상 생활에서부터 각종 산업분야에 이르기까지 전기 분야가 차지하는 비중은 매우 크다. 전기분야는 전기이론, 전기기기, 전력, 자동제어, 전기응용, 전기측정, 전기실습 등 여러 분야가 있으나, 전기실습은 공업계 고등학교 학생들에게 곡 필요한 과목이며, 다른 과목의 이해를 돕게 하는 기초적인 요소이다. 여기에서는 이러한 전기실습의 효과를 높이기 위하여 동영상으로 된 회로 분석도를 작성하였다.

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Improvement of Firing Elevation Driving Method for Towed Howitzer to Prevent Musculoskeletal Problems (근골격계 질환 예방을 위한 견인곡사포 고각조정 방법의 개선)

  • Park, Sung Ho
    • Journal of Korean Institute of Industrial Engineers
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    • v.42 no.2
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    • pp.122-128
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    • 2016
  • The purpose of this study is to improve the firing elevation driving method for towed howitzer to prevent the musculoskeletal disorders. To adjust the firing elevation, it is required to rotate the hand wheel and this work has been done manually in the firing test range as the same method as field artillery troops. In the firing test range, the motor-driven firing elevation adjustment device was developed to improve the working efficiency and safety. These were compared by using posture classification scheme of RULA and REBA. It was measured elapsed time to investigate the improved operational efficiency. The optimal posture of upper body to operate the hand wheel for field artillery troops was proposed.

A Study on Fluid Thansient Accommpanying Cilumn Separation in Oil Hydraulic Pipeline -Investigation on Two-Step Pressure Rise (유압 관로계에서 액주분리를 수반하는 유체과도현상에 관한 연구 -2단입력 상승현상에 관하여-)

  • 염만오;이진걸;이일영;김현기
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.12 no.5
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    • pp.984-991
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    • 1988
  • Liquid column separation occurs when the valve on the pipeline is closed rapidly in an oil hydraulic system. In this case two-step pressure rise is sometimes observed in a comparatively short pipeline. In this study the two-step pressure rise phenomenon was investigated experimentally and theoretically. The experiments showed that maximum pressure values during two-step pressure rise might exceed extremely the values computed by the theory of rigid-liquid-column separation. So the two-step pressure rise phenomenon appears one of important factors of pipe strength design. From the theoretical considerations based on the experimental and numerical results, the mechanism of two-step pressure rise phenomenon could be explained clearly.

A Study on aspect of development and the ideological backgrounds of a pond a place of Korea (한국(韓國) 고대(古代) 궁원지(宮苑池)의 전개양상(展開樣相)과 사상적(思想的) 배경(背景)에 관한 연구(硏究))

  • Oh, Seung-Youn
    • Korean Journal of Heritage: History & Science
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    • v.37
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    • pp.65-89
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    • 2004
  • Up to now, the studies for a pond of ancient palace of Korea are mainly achieved in a landscape architectural field. In fact, we can't grasp the general aspects but we are only heard about the fragmentary ruins and remains by the people who are in charge of an archaeological excavation. In this thesis, therefore, I attempt to grasp the relational categories of the ponds of an ancient palace of Korea, and find out the ideological backgrounds of the ponds of a palace construction through classify them excavated so far. The ancient ponds of Korea are divided to the class of square ponds(I) and curved ponds(II) according a shapes of planes. The class of square ponds(I) are subdivided to the form IA of the class of square ponds and form IB of the class of square ponds by whether it has an island, artificial hill and ornamental stone or not. And the class of the curved ponds(II) are divided to the form IIC that is only composed of curves in shore and the form IID that is composed of curves and straight lines. According the size, it is divided to a small size that is below the maximal diameter, 20m, and a large size that is more than 45m, after all, the ponds of the ancient palaces are devided to IAa, IAb, IBa, II Ca, IICb, IIDa. The square ponds and the curved ponds are co-exist from the initial stage when a pond of a place was found in our country and are succeeded or changed after Silla unified the three Kingdoms. In other words, we can infer a continuity from the earlier stage from the fact that there is a flat figure ground mainly constituted by the ponds of a palace mixed up of a straight line and a curved line in United Silla Kingdom while it succeeds the ponds of a palace that has a square form of Goguryo in Balhai. Different from the successional relation of the flat figure grounds, in an aspect of the elements of the construction, the site of the arbor at the top of the island and the bridge facilities in a field of a palace those are not exist in three Kingdoms period are appeared in United Silla Kingdom. The point that this aspect is simultaneously appeared in a neighboring country, or Japan, allows us to infer that there may be some motivations cause the changes in a construction of the ponds of a palace of Korea, China and Japan from the latter half of the 7th century to the first half of the 8th century. The ideological backgrounds of the ponds of a palace construction are divided roughly into Taoism and Buddhism. We can recognize that the ponds of a palace made up of the islands, the artificial hills and the garden rocks reflect Taiosm, considering the records of the ponds a palace of Korea and China are all use the term, Taoism, or the concrete statement represents that the islands, the artificial hills and the garden rocks are used in the description of the ponds of a palace of Korea. Both two are, therefore, obviously differentiated from the ponds of a palace that doesn't include them. We can conclude that the ponds of a palace that doesn't include them are colored by Buddhism since they are overtly distinguished from the class of curved ponds that reflect Taoism at the same period and they are identical with the site of an ancient temples in an aspect of their type and construction.

Effect of Period and Storehouse-Grade in Grain Storage and Degree of Milling on the Sensory Taste of Cooked Rice (벼의 저장에 있어 저장기간, 창고등급 및 도정도가 밥맛에 미치는 영향)

  • Yong-Woong Kwon;Jeon-Woo Bang
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.36 no.3
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    • pp.271-279
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    • 1991
  • The changes in fat acidity of brown rice and eating quality of rice during long term grain storage of unhulled rice were evaluated for the government managed rices. The Tongil type rice grains had consistently significantly lower fat acidity during three and half year storage than the Japonica type rice. On sensory evaluation of the fresh milled cooked rice the eating quality of the long term stored rices, 1987, 1988, and 1989 produce Tongil did not differ much each other even though increase in fat acidity by year of storage. The Japonica rices produced in 1989 and 1990 in different locations and stored there also did not differ much in eating quality. The grains stored in storehouses of super grade did not differ significantly from those stored in the first grades, but the grains stored (4 $^{\circ}C$, RH 50%) grains have kept the eating quality almost same as the fresh grains even after two and half years. A higher degree of milling did not improve significantly the sensory taste of cooked rice of the grains long term stored.

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Numerical Study on Turbulent Flow in a Conical Diffuser (원추형 디퓨져 내의 난류운동에 관한 수치해석적 연구)

  • 강신형;최영석
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.10
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    • pp.1971-1978
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    • 1992
  • A turbulent flow in a conical diffuser with total divergence angle of 8.deg. was numerically studied. The low Reynolds number k-.epsilon. model(Launder-Sharma model) was adopted to simulate the turbulence. The continuity and time averaged Navier-Stokes equations in a nonorthogonal coordinate system were solved by a finite volume method based on the fully elliptic formulation. The low Reynolds number k-.epsilon. model reasonably simulates the pressure recovery and the mean velocity components. However, there are also considerable discrepancies between predicted and measured shear stress distribution on the wall and turbulent kinetic energy distributions. It is necessary to investigate the flow structure at the entry of the diffuser, numerically as well as experimentally.

The Geographical Language and Location Characteristics of Rural Settlements focused on Miwon Myeon in the Integrated Cheongju City (농촌자연마을의 지명어와 입지특성에 관한 연구 -통합청주시 미원면을 중심으로-)

  • Kim, Tai-Young
    • Journal of the Korean Institute of Rural Architecture
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    • v.17 no.4
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    • pp.25-32
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    • 2015
  • This paper is to research the geographical language and location characteristics of 126 rural settlements focused on Miwon Myeon in the Integrated Cheongju City. The main results are as follows : Firstly, the geographical languages of 126 settlements are classified and categorized in the order of nature (91units, 72.22%), manmade and location related(35 Units, 27.78%). The geographical languages of nature, quite much in comparison with the others, are also classified into 39 'mountain', 46 'valley', and 6 'stream' units in location characteristics. Secondly, the geographical languages of nature have 46 'valley' units, much in comparison with the others. The open circular valleys are extended from Miwon Ri of town center to Gubang Ri along route 19. The closed valleys are placed in the west and north band of town center with a background of mountain range. The 46 'valley' units are distributed widely throughout these places. Thirdly, The geographical languages of 39 'valley' units except original 7 'valley' units are categorized with the secondary 'mountain'(rock and topography related), 'stream', 'manmade', and 'location related'. And so in considering the location characteristics of rural settlements, we will have to grasp the another meaning of the geographical language.

A Determination of Approximated Cylindrical Surfaces of Doubly Curved Surfaces for the Least Line Heating (최소 2차 가공을 위한 이중 곡면의 롤러 굽힘 형상 결정)

  • Dae-Kyu Yun;Jong-Gye Shin;Cheol-Ho Ryu
    • Journal of the Society of Naval Architects of Korea
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    • v.36 no.3
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    • pp.134-143
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    • 1999
  • The ship's bows and sterns are assembled with the curved blocks. In shipyards, the roller bending and the line heating or others are being used to fabricate such doubly curved shell. Firstly, the cylinder- or cone-type is formed through the roller bending, and then, the line heating is implemented to form the rest. This paper presents an algorithm to determine the direction for the roller bending and the shape to be formed as fabrication information. The direction for the roller bending is determined with Gauss mapping of the desired surface and the shape to form is calculated by comparing the bent shape with the desired shape.

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Individual identification by extraction of nail bed pattern of the finger nail using confocal scanning optical system (손톱하부면 초상(nail bed) 패턴의 콘포칼 광 스케닝 방법을 이용한 추출과 개인인증)

  • 김태근;김용우;김해일(주)미래시스
    • Korean Journal of Optics and Photonics
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    • v.13 no.2
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    • pp.155-161
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    • 2002
  • The nail bed is located under the finger nail. The arched portions of the nail bed, which contain a large number of capillary loops, are separated by the valley of the nail bed. The valley of the nail bed does not contain capillary loops. Light is scattered when it propagates through the dermis of skin, and human blood strongly absorbs the light with proper wavelength. By use of the optical properties of the nail bed, we propose an optical technique which extracts the nail bed image of the finger nail. After achieving nail bed images of each individual, we correlated between them. The correlation outputs show that we can identify individuals by comparing the peak heights of the correlation outputs.

Evaluation of Mechanical Properties on Cryogenic Structrual Steel JN1 Weldments and Heat Treated Materials by Using Miniaturized Small Specimen (소형 시험편에 의한 극저온 구조용강 JN1의 용접부 및 열처리재의 기계적성질 평가)

  • Gwon, Il-Hyeon;Hashida, Toshiyuki;Jeong, Se-Hui
    • Korean Journal of Materials Research
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    • v.6 no.9
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    • pp.905-918
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    • 1996
  • 초전도 마그네트 구조용 부재로 최근 개발된 오스테나이트계 스테인레스강 JN1 모재, GTA 용접부 및 열처리재에 대한 기계적 성질을 조사하기 위해 실온(293K)에서 극저온(4K)까지의 온도에서 소형펀치(Small Punch)시험을 실시하였다. GTA 용접부의 용융선 근방의 극저온 기계적 성질은 모재와 용접금속에 비해 크게 저하하였다. 4K에서 실험된 용융선 시험편으로 얻어진 하중-변위곡선상에서 부하의 초기 단계에 보통의 서레이션과 다른 pop-in이 관찰되었고, 이때 시험편 표면의 용융선 근처에서 약 0.1-1mm 정도의 크랙이 발생하였다. 열처리재의 기계적 성질은 열처리 시간과 온도의 증가 또는 시험온도의 저하에 따라 크게 저하되었다. 위의 결과에 기초하여 본 연구에서 실시한 소형 시험편을 사용하는 SP 시험법은 극저온에서 JN1 강의 모재와 열처리재뿐 만 아니라 GTA 용접부의 기계적 성질을 평가할 수 있는 유용한 시험법이었다.

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