• Title/Summary/Keyword: characteristics of the region

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The effects of oil supply conditions on the static characteristics of plain journal bearings (저어널 베어링의 정특성에 미치는 급유 조건의 영향)

  • 정경민;김경웅
    • Tribology and Lubricants
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    • v.6 no.2
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    • pp.76-87
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    • 1990
  • It is known that the effects of oil supply conditions on the characteristics of plain journal bearings are significant and especially the dynamic characteristics are affected by cavity region. For various shapes (axial groove, spiral groove, X-shape groove) and positions of oil grooves, the pressure distribution and the static performance of plain journal bearings are obtained with numerical methods. Elrods algorithm which implements JFO oil rupture/reformation boundary condition is used in order to take into account the effect of cavity region. It is shown that in the cases of axial groove or X-shape groove the load capacity and the attitude angle are affected by the groove position but the effect of spiral groove position is less significant.

An Equivalent Plate Model for The High-Frequency Dynamic Characteristics of Cylindrical Shells (원통형쉘의 고주파동적특성을 고려한 등가평판 모델링)

  • 이준근;이우식;박철희
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1997.10a
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    • pp.402-407
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    • 1997
  • For cylindrical shells, the closed-form solutions are limited only to the cases with special boundary and/or loading conditions. Though the finite element method is certainly a powerful solution approach for the general structural dynamics problems, it is known to provide reliable solutions only in the low frequency region due to the inherent high sensitivities of structural and numerical modeling errors. Instead, the spectral element method has been proved to provide extremely accurate dynamic responses even in the high frequency region. Since the wave characteristics of a cylindrical shell becomes identical to that of a flat plate as the frequency increases, an equivalent plate model (EPM) representing the high-frequency dynamic characteristics of a cylindrical shell is introduced herein. The EPM-based spectral element analysis solutions are compared with the known analytical solutions for the corresponding cylindrical shell to confirm the validity of the present modeling approach.

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Heat Transfer Characteristics in Impinging Air Jet with Hybrid Rod (하이브리드 로드를 갖는 충돌공기제트의 열전달특성에 관한 연구)

  • 표창기;박상록;김동춘;금성민;임장순
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.3
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    • pp.277-283
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    • 2000
  • The heat transfer characteristics for air jet vertically impinging on a flat plate which had a set of hybrid rod were investigated experimentally. The rod had a cross section made with a half of circular cross section and that of rectangular and was installed in front of the plate. The heating surface was given constant heat flux value of 1020 W/$m^2^{\circ]C$ and the problem parameters investigated were jet Reynolds number, nozzle-to-plate spacing and the rod size. The local and local average Nusselt number characteristics were found to be dependent on the rod size because the flow was disturbed by installing the rod. Higher convective heat transfer rate occurred in the whole plate as well as in the stagnation region.

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Study on the self-differentiation of the university students and Kinetic Femily Drawing Respondent Characteristics (대학생의 자아분화와 동적 가족화 반응 특성 연구)

  • Lee, Jung-Sook;Kim, Yun-Hee
    • Korean Journal of Human Ecology
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    • v.9 no.4
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    • pp.429-445
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    • 2000
  • This study was analyzed for the relationship between the self-differentiation of the university students and Kinetic Family Drawings that was responded their mental aspect. Results of this study were following. First, the level of self-differentiation by sex, age, region and grade was significantly different. Second, Kinetic Family Drawings respondent characteristics by their sex, age, region, grade and sibling order was significantly different. Third, in the relationship between the self-differentiation of the university students and Kinetic Family Braving respondent characteristics, when the group had less conflict and more interaction among family members, they could separate their subjective and objective tension and they could attach to their parents. In the case that crisis was occurred in their family, they had less possibility to represent dysfunctional communication style or regressive behaviors.

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An Experimental Study on Flow Characteristics for Dual-Structured Orifice (이중구조 오리피스 팽창장치의 유동특성에 관한 실험적 연구)

  • 곽경민;김하덕;이중형;배철호;김종엽
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.14 no.12
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    • pp.1039-1046
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    • 2002
  • To investigate the characteristics of orifice as an expansion devices, the experimental apparatus was made and experiments are being peformed using R22 and R290. The main idea of this control method of refrigerant flow rate with coupled orifices is to control the ON/OFF state of T and Ball type orifice corresponding to the subdivided region of thermal load. When system requires minimum thermal load, both T and Ball type orifices are closed, but refrigerant can flow through small hole of T type orifice. In regular thermal load, when ball type orifice is closed, T type orifice is opened and mass flow rate increase more than OFF state of T type orifice, due to large diameter. In maximum thermal load, both T and Ball type orifices are open and the much refrigerant can flow. The flow characteristics on T type orifice and parallel-combined orifice are obtained in the subdivided region of thermal load.

A Lip Detection Algorithm Using Color Clustering (색상 군집화를 이용한 입술탐지 알고리즘)

  • Jeong, Jongmyeon
    • Journal of the Korea Society of Computer and Information
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    • v.19 no.3
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    • pp.37-43
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    • 2014
  • In this paper, we propose a robust lip detection algorithm using color clustering. At first, we adopt AdaBoost algorithm to extract facial region and convert facial region into Lab color space. Because a and b components in Lab color space are known as that they could well express lip color and its complementary color, we use a and b component as the features for color clustering. The nearest neighbour clustering algorithm is applied to separate the skin region from the facial region and K-Means color clustering is applied to extract lip-candidate region. Then geometric characteristics are used to extract final lip region. The proposed algorithm can detect lip region robustly which has been shown by experimental results.

Study on a Quadruped Walking Robot with Omni-directional Characteristics (전방향 특성을 갖는 사족보행 로봇에 관한 연구)

  • Kim, Hee-Guk;Lee, Jun-Yong;Song, Nak-Yoon;Cho, Hwang
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1996.11a
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    • pp.815-819
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    • 1996
  • In this work, regular rotational gaits of the quadruped crawling robot required to change its moving direction without affecting be its orientation and its static stability margin are studied. The regular rotational gaits provide the quadruped crawling robot with omnidirectional characteristics. However, the ideal foothold region for each of legs of the quadruped crawling robot is assumed for simplicity. Nonetheless, it is expected that the results of this paper will provide the insight for both design of legs of the crawling robot with omnidirectional characteristics as well as its operation of the crawling robot system with specified stability margin.

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Research on the comparison on the ritual food of Gyeonggi and Gyungsangbuk-do province (경기와 경북지역의 제수 비교 연구)

  • 김정미;장성현;김종군
    • Korean journal of food and cookery science
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    • v.19 no.5
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    • pp.562-570
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    • 2003
  • The awareness of ritual foods in general rituals were surveyed and compared in the Gyeonggi and Gyungsangbuk-do areas in order to identify the characteristics of Korean rituals and establish desirable ritual foods. As materials for "Jeon" (fried pan cakes) in rituals, fish fillets, meat and vegetables were largely used in the Gyeonggi region. In the Gyeongbuk region, all three of these ingredients were the most highly used for "Jeon" also. In the case of rice cakes, "Songpyun" steamed on a layer of pine needles, "Jeolpyun" and "Sirudduk", with a red beans, were mostly used in Gyeonggi-do, while "Songpyun", "Jeolpyun" and "Ingelmi" were largely used in Gyeongsangbuk-do. As seasoned vegetables and herbs, fernbrakes, root of bell flowers, green bean sprouts and bean sprouts were largely used in Gyeonggi-do region, whereas, fernbrakes, bean sprouts, root of bell flowers and spinaches were mainly used in Gyeongbuk region. The use of fernbrakes was highest in both regions. With regard to the number of side dishes, 2∼3 kinds of seasoned herbs and 3∼4 kinds of fruits were mostly used, but with slightly higher numbers in the Gyeongsangbuk-do than the Gyeonggi-do region. With regard to liquor used for rituals, clear strained rice wine was used most in the Gyeonggi-do area, while more unrefined rice wine was used in the Gyeongbuk region. Meat was the most used ingredient in broth slices of dried meat and cod were highly used in the Gyeonggi region, but slices of dried squid were most widely used in the Gyeongbuk region. Most households in both regions tended not to use raw fish in the rituals, and as for the ingredients of Korean Kabobs, meat was the most widely used, then fish and finally vegetables were the most used ingredients. Beef soup was the most used, but more green vegetable soup was used in the Gyeongbuk than the Gyeonggi region. Sweet drink made from fermented rice (sikhe) was generally used in the rituals. It was the most widely used in the Chusok-Hangawi Ritual in the Gyeonggi region, while it was used in the New Year's Ritual in the Gyeongbuk region.

Electrical characteristics of the SOI RESURF LDMOSFET with step doped epi-layer (Step doping 농도를 가지는 SOI RESURF LDMOSFET의 전기적 특성 분석)

  • Kim, Hyoung-Woo;Seo, Kil-Soo;Kim, Ji-Hong;Kim, Nam-Kyun
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2004.07a
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    • pp.361-364
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    • 2004
  • Surface doped SOI RESURF LDMOSFET with recessed source region is proposed to improve the on- and off-state characteristics. Surface region of the proposed LDMOS structure is doped like step. The characteristics of the proposed LDMOS is verified by two-dimensional process simulator ATHENA and device simulator ATLAS[1]. The numerically calculated on-resistance($R_{ON}$) of the proposed LDMOS is $10.36\Omega-cm$ and breakdown voltage is 205V when $L_{dr}=7{\mu}m$ with step doped surface.

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Features of Korean Rainfall Variability by Western Pacific Teleconnection Pattern (서태평양 원격패턴에 따른 한국 4월 강수량의 변동 특성)

  • Choi, Jae-Won;Park, Ki-Jun;Lee, Kyungmi;Kim, Jeoung-Yun;Kim, Baek-Jo
    • Journal of Environmental Science International
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    • v.24 no.7
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    • pp.893-905
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    • 2015
  • This study analyzes the correlation between Western Pacific (WP) teleconnection pattern index (WPI) in April during 1954-2008 and rainfall amounts in the same month. Based on the results, it is identified that there have been strong positive correlations between central China, Korea and the southwestern part of Japan in the East Asian region. Through differences between 10 positive WP years and 10 negative WP years selected from the April WPI excluding ENSO years, it is found that rainfall amounts increase in April of positive WP years due to the following characteristics. Increases in rainfall amounts are evident in the East Asian middle latitudinal region where the positive correlation between the two variables is the highest and this is because anomalous southwesterlies are strengthened in the East Asian middle latitudinal region due to the spatial pattern of a south-low-north-high anomalous pressure system centered on this region that is made by anomalous anticyclones centered on the southeastern side of the region and other anomalous anticyclones centered on the northeastern side of the region. In addition, anomalous westerlies (jet) are strengthen in the upper troposphere of the East Asian middle latitudinal region and as a result, anomalous upward flows are strengthened in this region and thus anomalous warm air temperatures are formed in the entire level of the troposphere in the region. In addition to atmospheric environments, anomalous warm sea surface temperatures are formed in the seas in the East Asian middle latitudinal region to help the rainfall amount increases in the East Asian middle latitudinal region.