• Title/Summary/Keyword: 박정길

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An Analysis of the Critical factors Making Koreans Poor Readings (한국인의 독서부진 요인분석에 관한 연구)

  • 박정길
    • Journal of Korean Library and Information Science Society
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    • v.34 no.2
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    • pp.43-77
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    • 2003
  • The purpose of this study is to analyze the critical factors that have made Koreans such poor readers. What is the factors in make poor progress in reading of the Korean. The emphasis was put on identifying some indigenous barriers against buiding ‘good’ reading habits. Especially investigated are the following three aspects: historical, socio-educational, and psychological. This study suggested the policies and strategies for correcting and improving the poor reading of Korean.

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Stress Distribution of Occlusal Loading Applied on Cervical Region Using 3D Finite Element Analysis (교합하중에 의한 치경부 응력분포의 3차원 유한요소해석)

  • Woo S.G.;Kim G.H.;Son K.;Park J.K.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2006.05a
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    • pp.521-522
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    • 2006
  • Occlusal loading is considered as the main factor of noncarious cervical lesions. The goal of this study is to identify stress distribution using three dimensional finite element analysis, when occlusal loading is applied on the cervical lesion of human tooth. A finite element model was constructed from micro-CT image and three kinds of static force(500 N) were assumed. In all cases stress concentrates on the same area in the cement-enamel junction. This finding is consistent with published experimental results.

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Electrochemical Reduction of Nitrate Ion in an Aqueous Solution (수용액에서 질산성 질소의 전기화학적 환원거동)

  • Park, J.K.;Jeon, C.J.;Lee, C.K.
    • Proceedings of the Korean Institute of Resources Recycling Conference
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    • 2003.10a
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    • pp.246-251
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    • 2003
  • 전기분해법을 이용하여 수용액 중의 질산성 질소의 환원거동에 대한 연구를 통하여 수용액중의 질산 함량을 제어하는 연구를 수행하였다. 촉매전극을 채택한 복극전해조에서 30분의 조업에 질산 100ppm 이하의 저농도 용액은 70%, 300ppm 이상의 고농도의 경우는 90%까지 질소를 용이하게 제거할 수 있었다. 초기 질소농도가 증가하면서 한계전류밀도도 크게 증가하였으며, pH가 감소할수록 환원전류가 증가하였다. 그리고 수용액의 pH는 질소 환원반응기구에 큰 영향을 주는 것으로 판명되었으며, 산성에서는 질소형태로 중성 혹은 염기성에서는 암모니아 형태로 환원되는 것으로 추정된다.

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Analysis of Relationship between Structure and Acoustic Character of Natural Waterfall (자연폭포의 강조와 청각적 특성의 관계분석)

  • 정성관;박정길
    • Journal of the Korean Institute of Landscape Architecture
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    • v.18 no.1
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    • pp.19-32
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    • 1990
  • The perception of landscape structure can he formed mode clearly, with including an auditory stimulus to a visual aspect. The waterfall, as an landscape element, will be considered of not only it's function and structure in landscape architecture designing but also harmony with environment which it has been situated, and contribution to the public goad. The purpose of this study was to establish more 7rational and practical design theory for the construction of waterfall. The number of subjects investigated were 47 of waterfall located in Mt. Palgong. In this study, the acoustic character of the waterfalls were investigated as an excellent effect to mask easily sensible noises. The correlations between the structure of waterfalls and water 1a17ing sound, which were useful for waterfall design and construction, were examined. It was discovered that the position of double distance of waterfall height From the waterfall is significant in the visual and acoustic perception of waterfall.

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Infrared Image Based Human Victim Recognition for a Search and Rescue Robot (수색 구조 로봇을 위한 적외선 영상 기반 인명 인식)

  • Park, Jungkil;Lee, Geunjae;Park, Jaebyung
    • Journal of Institute of Control, Robotics and Systems
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    • v.22 no.4
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    • pp.288-292
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    • 2016
  • In this paper, we propose an infrared image based human victim recognition method for a search and rescue robot in dark environments, like general disaster situations. For recognizing a human victim, an infrared camera on a RGB-D camera, Microsoft Kinect, is used. The contrast and brightness of the infrared image are first improved by histogram equalization, and the noise on the image is removed by morphological operation and Gaussian filtering. For recognizing a human victim, the binarization and blob labeling methods are applied to the improved image. Finally, for verifying the effectiveness and feasibility of the proposed method, an experiment for human victim recognition is carried out in a dark environment.

Implementation of system security platform based on Cortex-M3 (Cortex-M3기반 System 보안 플랫폼 구현에 대한 연구)

  • Park, Jung-kil;Kim, Young-kil
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.10a
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    • pp.317-320
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    • 2016
  • In embedded system, if firmware code is opened by other company, must devise hardware copy prevention. That guard valuable product. Not used security IC, Suggested platform is source code open method that prevent core code and hardware copy. And that open firmware code for other company programmer. Suggest system security platform based on Corex-M3. that consist of IAP(In-application programing) and APP(Applicataion). IAP contain core code and security confirm code. APP is implement by other company developer using core function prototype.

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Design and Implementation of a Mobile Robot with a Variable Structure for Tip-over Prevention (전복방지를 위한 가변 구조 이동 로봇의 설계와 구현)

  • Lee, Sungmin;Park, Jungkil;Park, Jaebyung
    • Journal of Institute of Control, Robotics and Systems
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    • v.21 no.4
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    • pp.356-360
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    • 2015
  • In this paper, we design and implement a mobile robot with variable structure for tip-over prevention. The mobile robot is designed for the purpose of stable drive and work in outdoor terrain. The outdoor terrain is rough and uneven. In this terrain, the tip-over of the mobile robot can occur while driving and working. Therefore, the structure of the mobile robot must be designed in consideration of stable drive and work. The proposed structure is defined as an X-shape for overall balance of the mobile robot. The shape is designed by using a multi-level structure for reducing the size of the robot. To verify the effectiveness of the proposed design, we analyze the tip-over characteristics according to the height of gravitational center and the extension length of the robot. Finally, we develop a prototype of the mobile robot with variable structure, taking the results of the tip-over analysis into consideration.

Vibration Characteristics of the Fruit and Vegetables during Transportation (II) -Vibration Characteristics of the Fruit and Vegetables using FEM- (유통중 청과물의 진동 특성 연구 (II) -유한요소법을 이용한 청과물의 진동특성-)

  • Kim, Man-Soo;Jung, Hyun-Mo;Kim, Ghi-Seok;Park, Chung-Gil
    • Korean Journal of Agricultural Science
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    • v.30 no.2
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    • pp.184-190
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    • 2003
  • Finite element method(FEM) was used to obtain an approximate solution, since the mathematical formulations for the problem are complex and cannot be solved analytically. In this study, the fruit as well as the aluminum support on vibrator are discretized into small elements, and the approximate functions are used to describe the displacements in each element in terms of nodal values, and because of the complexity of the problem of viscoelastic materials such as the fruit and vegetables, it was necessary to validate the modeling approach before pear simulations were performed, and the finite element modeling approach was first validated by comparing the results obtained from simulation and experiment for the pear in the frequency range 3 to 150 Hz and acceleration level of 0.25 G-rms. Based on the relatively good agreement between simulated and measured frequencies for the pear, finite element models of tomato and oriental melon were created to study the vibration characteristics of the fruit and vegetables. The resonance frequencies of the pear, tomato and oriental melon using FEM were 62.50, 39.45 and 62.73 Hz and the peak accelerations of them using FEM were 2.21, 1.38 and 1.98 G-rms.

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The Effect of Addition of Potato Starch on the Frozen Dough (감자 전분의 첨가가 냉동 반죽에 미치는 영향)

  • 이명구;이종민;장준형;박정길
    • The Korean Journal of Food And Nutrition
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    • v.13 no.5
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    • pp.403-410
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    • 2000
  • This study was carried out to understand the effect of addition of potato search on the frozen dough. The characteristics of frozen dough were measured by the farinogram, the extensogram and the amylogram. The results of these measurements show that the dough added with starch has higher stability than the control. The physical and chemical change of the dough were measured in accordance with the period of the frozen storage. The dough added with starch showed smaller physical and chemical change than control, which means that the starch prevents the frozen dough from the deterioration during the frozen storage. It is supposed from this result that the starch protects the activity of yeast and the structure of gluten matrices from frozen damage. It is understood from this study that addition of potato starch into frozen dough improve the stability of the frozen dough.

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An Optimization of Restoration Method at Class V Lesion of a Finite Element Tooth Model (5급 병소가 있는 치아 유한요소 모델의 수복방법 최적화)

  • Kim, Kwang-Hoon;Woo, Sung-Gwan;Son, Kwon;Park, Jeong-Kil
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.32 no.8
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    • pp.678-684
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    • 2008
  • A general treatment is to restore abfraction lesions with dental filler materials to reduce stress concentration. A material should be selected from various dental products based on long term experiences of dentist or personal preference concerning filler methods. A quantitative criterion is necessary to make an evaluation of the results as dentists decide treatment methods and dental materials relying on their clinical experiences. The purpose of this study is to find an optimal restoration method and material for noncarious cervical lesions using the finite element method. An objective function was defined to minimize the sum of tension or compression stress. Trial-and-error and approximation were used to find an optimal restoration method. An optimal solution was to fill TetricFlow inside the lesion and Z100 in the remaining region. The most desirable thickness ratio of the two filler materials was 0.125 with trial-and-error and it was similar to the results of approximation, 0.121 and 0.132.