• 제목/요약/키워드: General machinery

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Recognition of Profile Contours of Human Face by Approximation - Approximation -

  • Yang, Yun-Mo
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.679-682
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    • 1988
  • From the viewpoint of general recognition system, B-spline is introduced for the approximation and recognition of human profile contours. Profile contour is approximated to the cublic B-spline curve by least square fitting so that B-Spline nodes nearly correspond with the curvature extrema of the contour. This method is designed for the spline to be good features in recognition, and also showed good approximation compared with the variants of B-spline appraximation.

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Recognition of Profile Contours of Human Face by Approximation - Recognition

  • Yang, Yun-Mo
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.683-686
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    • 1988
  • In the recognition of similar patterns like profile contours of human faces, feature measure plays important role. We extracted effective and general feature by B-spline approximation. The nodes and vertices of the approximated curve are normalized and used as features. Since the features have both local property of curvature extrema and global property by B-spline approximation, they are superior to those of curvature extrema of the profile contour. For the image data of six sets of 56 persons, some of which are ill-made, averaged accuracy rate of 97.6 % is obtained in recognizing combinational 333 test samples.

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Aerodynamic Design Program for Centrifugal/Mixed-flow Compressors - Part I : Meanline Design and Performance Prediction - (원심/사류압축기의 공력설계 프로그램 개발 - 제1부 : 평균유선 설계/성능해석 -)

  • Oh, Jong-Sik
    • 유체기계공업학회:학술대회논문집
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    • 2003.12a
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    • pp.457-463
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    • 2003
  • A general program of meanline design and/or performance prediction for centrifugal/mixed-flow compressors is successfully commercialized using various empirical loss models. 4 types of diffusers, 3 types of exit elements, shrouded/unshrouded impellers and real gas option are included in the program capabilities. Total 16 cases of benchmark test results proved its reliability to be effectively utilized in the development processes.

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Aerodynamic Design Program for Centrifugal/Mixed-flow Compressors - Part II : Three Dimensional Profile Design of Impellers - (원심/사류압축기의 공력설계 프로그램 개발 - 제2부 : 임펠러의 3차원 형상설계 -)

  • Oh, Jong-Sik
    • 유체기계공업학회:학술대회논문집
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    • 2003.12a
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    • pp.464-468
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    • 2003
  • A general program of three dimensional profile design of impellers for centrifugal/fixed-flow compressors is successfully commercialized using Bezier curves and quasi-3D flow analysis methods. Control points for meridional hub and shroud contours and blade camberline angles are arbitrarily changed to give smooth Bezier curves. With specified blade normal thicknesses, contructed geometry is instantly analyzed using flow analysis methods to be checked.

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SENSITIVITY OF SHEAR LOCALIZATION ON PRE-LOCALIZATION DEFORMATION MODE

  • Kim, Kwon--Hee-
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1992.03a
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    • pp.83-102
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    • 1992
  • As shear localization is observed in different deformation modes, an attempt is made to understand the conditions for shear localization in general deformation modes. Most emphasis in put upon the effects of pre-localization deformation mode on the onset of shear localization and all the other well-recognized effects of subtle constitutive features and imperfection sensitivity studied elsewhere are not investigated here. Rather, an approximate perturbation stability analysis is performed for simplified isotropic rigid-plastic solids subjected to general mode of homogeneous deformation. Shear localization is possible in any deformation mode if the material has strain softening. The incipient rate of shear localization and shear plane orientations are strongly dependent upon the pre-localization deformation mode. Significant strain softening is necessary for shear localization in homogeneous axisymmetric deformation modes while infinitesimal strain softening is necessary for shear localization in plane strain deformation mode. In any deformation mode, there are more than one shear plane orientation. Except for homogeneous axisymmetric deformation modes, there are two possible shear plane orientations with respect to the principal directions of stretching. Some well-known examples are discussed in the light of the current analysis.

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Air Influx Characteristics of Turbo Pumps (공기 유입시의 터보펌프 특성)

  • Kim, You-Taek;Nam, Cheong-Do;Kang, Ho-Keun;Lee, Young-Ho
    • 유체기계공업학회:학술대회논문집
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    • 2004.12a
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    • pp.43-48
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    • 2004
  • A screw-type centrifugal pump was manufactured to carry solids primarily and its impeller has a wide flow passage. However, the effect of flow passage shape on delay of the choke due to entrained air has not been clarified yet. Moreover, because its impeller has a particular shape, only few studies have tried to clarify the pump performance and details of internal flow pattern of that pump. For that reason, we carried out the pump performance experiment under air-water two-phase flow condition with different impeller tip clearances, pump rotational speeds and void fractions by using a small screw-type centrifugal pump designed to acquire basic data. In a general centrifugal pump, it was reported that loss of pump head from single-phase flow to the choke due to air entrainment new the best efficiency point was large. However, the loss near the best efficient point in a screw-type centrifugal pump became less than that in a general centrifugal pump.

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A Study on Analysis of Ice Load Measured during the Voyage in the Arctic Sea (북극해 운항 중 계측된 빙하중에 대한 분석 연구)

  • Lee, Tak-Kee;Kim, Tae-Wook;Rim, Chae Whan;Kim, Heung-Sub
    • Journal of the Society of Naval Architects of Korea
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    • v.51 no.2
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    • pp.107-113
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    • 2014
  • The icebreaking research vessel, ARAON had her second ice trial in the Arctic Sea from 16th July to 12th August 2010. During the voyage, the local ice loads acting on the bow of port side were measured from 14 strain gauges. The measurements were also carried out in ice waters with various ice concentration ratio as well as the icebreaking performance tests. In this study, the ice loads measured during the 'general' operation in ice waters were analyzed. As a first step, the relationship between the location of strain gauges and the ice loads were investigated, and then the possibility for observation of higher ice loads was estimated based on the probability density function. The relationship between the ship speed and the ice load was also investigated. 718 peak stresses data higher than 20 MPa obtained from strain gauges array attached in longitudinally and vertically was analyzed. In general, the ice load increases as the ship speed increases in the low ship speed range, and ice load decreases as the ship speed is greater than a certain speed.

The Comparative Advantage of Intermediate Goods Trade in East Asia and Free Trade Agreement (동아시아 국가 간 부품무역 비교우위와 자유무역협정)

  • Kwon, Taek-Ho;Joo, Kyeong-won
    • Korea Trade Review
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    • v.41 no.1
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    • pp.159-186
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    • 2016
  • This study analyzes the degree of dependency and comparative advantage of each country for intermediate goods trade in East Asia, which predicts the comparative advantage of the intermediate goods trade and fragmentation in East Asia when the FTA arrangement in East Asia is implemented. The results are as follows. First, the share of intra-regional trade in the intermediate goods in East Asia has increased over time, implying the deepening of interdependency in intermediate goods trade within the East Asia. Second, Korea is a net exporter in intermediate goods trade for China and ASEAN, whereas it is a net importer for Japan. Japan is a high net exporter for all East Asia, while China is a net importer for Korea, Japan and ASEAN. If FTA arrangement in East Asia is implemented, Japan and Korea will be key suppliers of the intermediate goods for East Asia, while China and ASEAN will play a role of the manufacturing factory through the import of intermediate goods. Third, Korea has a comparative advantage in intermediate trade of electric and electronics and transport vehicle industry in East Asia. Japan has a comparative advantage in all of electric and electronics, transport vehicle, precision instrument, general machinery industry, whereas China has a comparative advantage only in electric and electronics intermediate trade in East Asia. The intra-industry trade of the intermediate goods in precision instrument, general machinery industry is expected to grow among Korea, Japan and China.

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A Study on the Architectural Planning of the X-ray Unit in General Hospital (종합병원 일반 및 특수촬영유니트의 건축계획에 관한 연구)

  • Youn, Woo-Young;Chai, Choul-Gyun
    • Journal of The Korea Institute of Healthcare Architecture
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    • v.12 no.3
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    • pp.27-34
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    • 2006
  • Planning for the space of the Media Medical Department requires the details about the efficiency of the equipment and the operation in professional sector. For that, as designing, it is necessary to keep communicating with the experts on the technology and the officials from the company producing the equipment. One of the common concerns is not only how to insure enough room for the future extension and the upgrade of the equipment, as concerning the scale of the hospital, but the plan to cover movie cameras. As technology has been developed, despite the fact that machinery tend to be small, it can be possible to require continuously about the concerns of the scale because the camera taking body-picture tend to be much bigger and more complicated than before. Currently used diagnostic media techniques are divided by the method and the feature of the equipment such as Diagnostic X-ray, Ultrasound, CT, MRI, Angiography. The general and special photographing units which are used more than the other diagnostic parts, must be planned not for experiencing any inconvenience and unnecessary risks for the patients and must accept technical requirements. Also, it must be designed not to be seen as a clinic zone, as concerning the psychological stability of the patients. However, study of the general and special photographing units among the domestic general hospitals is insufficient. Also, as there is shortage of the material considering the development of the equipment, when planning, it's involving a lot of difficulties. Thus, this study has got a purpose on giving the basic material which is essential for further study, as suggesting the planning guidelines and the alternative plans for the general and special photographing units in a general hospital.

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A Comparative Study on Ice Load Characteristics between General and Ice-breaking Operations in Ice-covered Waters (빙해지역 일반 운항 및 쇄빙 운항 시의 빙하중 특성 비교 연구)

  • Lee, Min-Woo;Kwon, Yong-Hyeon;Rim, Chae-Whan;Lee, Tak-Kee
    • Journal of Ocean Engineering and Technology
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    • v.29 no.1
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    • pp.28-33
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    • 2015
  • The icebreaking research vessel ARAON had her second ice trial in the Arctic Ocean from July 16 to August 12, 2010. In this study, the ice loads measured during the “general” operation and “ice breaking” operation in ice-covered waters were analyzed and compared. Whereas the “general” operation stands for the voyage in the water partially covered by ice, the “ice breaking” operation involved substantial ice floes for the ice breaking performance test. Based on the measured data, comparisons of the relationship between the ship speed and ice load, and between the locations of strain gauges and ice loads were investigated. Peak stresses higher than 20 MPa were found. The longitudinal and vertical correlations between the measurement location and ice load were analyzed, and the probability of peak stress was calculated. As a result, the probability function for higher ice loads during both operation modes was expressed in an exponential and power forms.