• Title/Summary/Keyword: quadrant analysis

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A Case of Clonorchiasis with Clinical Presentation of Eosinophilic Pneumonia (호산구성 폐렴으로 발현된 간흡충증 1예)

  • Lee, Deog-Young;Kim, Sung-Jun;Lee, Jong-Hyun;Kim, Dong-Wook;Lee, Jin-Kwan
    • Tuberculosis and Respiratory Diseases
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    • v.45 no.3
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    • pp.643-648
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    • 1998
  • Although clonorchiasis is one of the most common parasitic infections in Korea, it is unusual that the disease presents peripheral eosinophilia and pulmonary infiltrations.(eosinophilic pneumonia) A case of clonorchiasis manifested as diffuse nodular pulmonary infiltrations was presented. The patient had a mild to moderate pain on the right upper quadrant of the abdomen, cough, dyspnea, and unknown cause of marked eosinophilia (up to 71.4% of total white blood cell count). The causal organism, clonorchis sinensis was found by the identification of parasite ova in the stool We confirmed eosinophilic pneumonia with bronchoalveolar larvage analysis and transbronchial lung biopsy. With corticosteroid and praziquantel treatment, clinical symtoms and pulmonary infiltrations on the chest roentgenograms had rapidly improved. We report a case of eosinophilic pneumonia related to clonorchiasis and review the pertinent literature.

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Operational Analysis of Energy Storage System to Improve Performance of Wind Power System with Induction Generator (농형유도 풍력발전기의 성능개선을 위한 에너지저장장치의 동작특성 분석)

  • Lee, Ji-Heon;Shim, Myong-Bo;Lee, Hye-Yeon;Han, Byung-Moon;Yang, Seung-Chul
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.6
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    • pp.1138-1145
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    • 2009
  • This paper presents an active and reactive power compensator for the wind power system with squirrel-cage induction generator. The output power of a wind power system changes irregularly according to the variation of wind speed. The developed system is able to continuously compensate the active and reactive power. The 3-phase inverter operates for the compensation of reactive power, while the DC/DC converter with super-capacitors operates for the compensation of active power. The operational feasibility of the proposed model was verified by simulations with PSCAD/EMTDC and the feasibility of hardware implementation was confirmed by experimental works with a scaled hardware model. The proposed compensator can be expected that developed system may be used to compensated the abrupt power variation due to sudden change of wind speed or sudden power-drop by tower effect. It can be also applied for the distributed generation and the Micro-Grid.

Organized structure of turbulent boundary layer with rod-roughened wall (표면조도가 난류구조에 미치는 영향)

  • Lee, Jae-Hwa;Lee, Seung-Hyun;Kim, Kyoung-Youn;Sung, Hyung-Jin
    • 한국전산유체공학회:학술대회논문집
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    • 2008.03b
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    • pp.189-192
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    • 2008
  • Turbulent coherent structure near rod-roughened wall are investigated by analyzing the database of direct numerical simulation of turbulent boundary layer. The roughness sublayer id defined as two-point correlations are not independent of streamwise locations around roughness. The roughness sublayer based on the two-point spatial correlation is different from that given by one-point statistics. Quadrant analysis and probability-weighted Reynolds shear stress indicate that turbulent structures are not affected by surface roughness above the roughness sublayer defined by the spatial correlations. The conditionally-averaged flow fields associated with Reynolds shear stress producing Q2/Q4 events show that though turbulent vortices are affected in the roughness sublayer, these are very similar at different streamwise locations above the roughness sublayer. The Reynolds stress producing turbulent vortices in the log layer have almost the same geometrical shape as those in the smooth wall-bounded turbulent flows. This suggests that the mechanism by which the Reynolds stress is produced in the log layer has not been significantly affected by the present surface roughness.

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A Study on the Improvement of Accuracy of Close-Range Photogrammetry Analysis by Using Non-metric Camera (비측량용(非測量用) 사진기(寫眞機)에 의(依)한 근접사진(近接寫眞) 해석(解析)의 정확도(正確度) 향상(向上)에 관(關)한 연구(研究))

  • Kang, Joon Mook;Oh, Won Jin;Han, Seung Hee
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.12 no.2
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    • pp.151-159
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    • 1992
  • In close-range photogrammetry, to employ non-metric camera especially for the purpose of precise measurement, systematic errors must, first of all, be corrected as they have a great influence on accuracies of results. For it, fiducial marks was built in non-metric camera and the factors such as PPS, PPA, EFL, CFL, and radial lens distortion coefficients for each quadrant were calibrated through collimator test. Also, the coefficients of both radial and tangential lens distortion were calibrated from analytical plumb line method and therefore main systematic errors could be effectively corrected. Using the calibrated non-metric camera, close-range photogrammetry could be successfully accomplished and accuracies could be improved sharply.

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Characteristics of Wind Direction Shear and Momentum Fluxes within Roughness Sublayer over Sloping Terrain (경사가 있는 지형의 거칠기 아층에서 풍향시어와 운동량 플럭스의 특성)

  • Lee, Young-Hee
    • Atmosphere
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    • v.25 no.4
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    • pp.591-600
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    • 2015
  • We have analyzed wind and eddy covariance data collected within roughness sublayer over sloping terrain. The study site is located on non-flat terrain with slopes in both south-north and east-west directions. The surface elevation change is smaller than the height of roughness element such as building and tree. This study examines the directional wind shear for data collected at three levels in the lowest 10 m in the roughness sublayer. The wind direction shear is caused by drag of roughness element and terrain-induced motions at this site. Small directional shear occurs when wind speed at 10 m is strong and wind direction at 10 m is southerly which is the same direction as upslope flow near surface at this site during daytime. Correlation between vertical shear of lateral momentum and lateral momentum flux is smaller over steeply sloped surface compared to mildly sloped surface and lateral momentum flux is not down-gradient over steeply sloped surface. Quadrant analysis shows that the relative contribution of four quadrants to momentum flux depends on both surface slope and wind direction shear.

Relations of Near-Wall Streamwise Vortices to Wall Pressure Fluctuations in a Turbulent Boundary Layer (난류경계층내 주유동방향 와구조와 벽압력 변동간의 상관관계)

  • Seong, Hyeong-Jin;Kim, Jung-Nyeon;Choe, Jeong-Il
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.25 no.8
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    • pp.1068-1076
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    • 2001
  • The relations between wall pressure fluctuations and near-wall streamwise vortices are investigated in a spatially-developing turbulent boundary layer using the direct numerical simulation. The power spectra and two-point correlations of wall pressure fluctuations are presented to validate the present simulation. Emphasis is placed on the identification of the correlation between wall pressure fluctuations and streamwise vorticities. It is shown that wall pressure fluctuations are directly linked with the upstream streamwise vortices in the buffer region of the turbulent boundary layer. The maximum correlation occurs with the spanwise displacement from the location of wall pressure fluctuations. The conditionally-averaged vorticity field and the quadrant analysis of Reynolds shear stress indicate that the sweep events due to streamwise vortices generate positive wall pressure fluctuations, while negative wall pressure fluctuations are created beneath the ejection events and vortex cores. The instantaneous flow field and time records reveal that the rise of high wall pressure fluctuations coincide with the passages of the upstream streamwise vortices.

Organized Structure of Turbulent Boundary Layer with Rod-roughened Wall (표면조도가 있는 난류경계층 내 난류구조)

  • Lee, Jae-Hwa;Lee, Seung-Hyun;Kim, Kyoung-Youn;Sung, Hyung-Jin
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.32 no.6
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    • pp.463-470
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    • 2008
  • Turbulent coherent structures near rod-roughened wall are investigated by analyzing the database of direct numerical simulation of turbulent boundary layer. The surface roughness rods with the height $k/{\delta}=0.05$ are arranged periodically in $Re_{\delta}=9000$. The roughness sublayer is defined as two-point correlations are not independent of streamwise locations around roughness. The roughness sublayer based on the two-point spatial correlation is different from that given by one-point statistics. Quadrant analysis and probability-weighted Reynolds shear stress indicate that turbulent structures are not affected by surface roughness above the roughness sublayer defined by the spatial correlations. The conditionally-averaged flow fields associated with Reynolds shear stress producing Q2/Q4 events show that though turbulent vortices are affected in the roughness sublayer, these are very similar at different streamwise locations above the roughness sublayer. The Reynolds stress producing turbulent vortices in the log layer ($y/{\delta}=0.15$)have almost the same geometrical shape as those in the smooth wall-bounded turbulent flows. This suggests that the mechanism by which the Reynolds stress is produced in the log layer has not been significantly affected by the present surface roughness.

A Study on the Inter-Korean Cooperation for Natural Disaster Damage Reduction Using Spatial Information

  • Lee, Sunmin;Song, Taejung;Lee, Moung-Jin
    • Korean Journal of Remote Sensing
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    • v.35 no.1
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    • pp.163-177
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    • 2019
  • As inter-Korean relations progress, the issue of natural disasters which could directly affect the lives of the people in both Koreas, has not yet been discussed. Considering the current status of inter-Korean relations and the ongoing disaster-related damage in North Korea, it is imperative to establish a technical plan at the pan-governmental level to reduce the damage from natural disasters. The purpose of this study is to secure the Korea Peninsula against natural disasters by organizing South Korea's science and technologies related to natural disasters in order to reduce the damage, and to evaluate the applicability of said technologies. The situation of natural disasters in North Korea for 17 years has been summarized and reclassified based on eight types of natural disasters. Technologies related to natural disasters in South Korea were also investigated and reclassified. Based on the data, a priority evaluation was performed and the prioritization of technology application for each natural disaster type in North Korea was calculated through a quadrant analysis. As a result, the three major categories of high-priority technologies were classified as natural disaster monitoring with remote sensing and spatial information technology, construction of research basis and database based on geographic information system (GIS) and integrated management of complex natural disasters.

Derived of agenda priority for research and development with physical therapy technology (물리치료 기술 개발 방향 정립을 위한 세부 연구 분야 우선순위 도출)

  • Kim, Hyeong Geun;Ha, Hyun Geun;Bae, Young-Hyeon
    • Journal of Korean Physical Therapy Science
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    • v.29 no.1
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    • pp.15-29
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    • 2022
  • Background: The purpose of this study was to suggest agenda priorities for research and development with physical therapy technology. Design: Cross-sectional study. Methods: A survey was consecutively done to 62 experts working in physical therapy research areas to investigate the priority of the categories. Paired T-tests and Importance-Performance Analysis using SPSS 21.0 package were conducted to find the differences between importance and satisfaction of the categories and the order of priority. Results: In results, it was developed that the research and development with physical therapy technology were divided with 18 categories. And the importance were significantly higher than satisfaction in 18 categories. Specifically, categories about assistive technology and robot rehabilitation were found to be on the high importance and lower performance quadrant. Conclusion: In sum, this study was meaningful in finding usage categories of research and development with physical therapy technology and investigating Importance-Performance differences for deriving research and development with physical therapy technology.

Rotational Stability of AcrySof Toric Intraocular Lens Over Time: Influence of Capsulorhexis Contraction

  • Kim, Joong Hee;Cho, Kyong Jin
    • Medical Lasers
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    • v.9 no.1
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    • pp.44-50
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    • 2020
  • Background and Objectives To evaluate the rotational stability of AcrySof toric intraocular lenses (IOL) by considering lapse of postoperative time and influence of capsulorhexis contraction. Materials and Methods A prospective, masked, single center study was conducted on 19 patients who had undergone microcoaxial cataract surgery and AcrySof toric IOL implantation. Slit-lamp retroillumination photographs of anterior segments were obtained from all patients after 1 week, 1 month and 3 months post-surgery. The degree of alteration of the postoperative IOL axis alignment and the amount of anterior capsular shrinkage were analyzed using Adobe Photoshop software. Results The mean degree of toric IOL axis misalignment was 2.18 (±20.2) degrees at 3 months follow-up. Quadrant analysis of the capsulorhexis aperture area at 1 week and 1 month post-operative, showed counterclockwise IOL rotation when the capsule contraction was dominant in the haptic part as well as clockwise rotation when dominant in the non-haptic part (p = 0.015). Conclusion The direction and degree of AcrySof toric IOL rotation differed throughout the follow-up period. Since most misalignments were found on the first post-operative day, physicians should try to minimize peri-operative risk factors that influence IOL rotation. There was also a correlation between the part of anterior capsule contraction and the direction of IOL rotation.