• 제목/요약/키워드: External change

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Baseline Refinement for Topographic Phase Estimation using External DEM

  • Lee, Chang-Won;Moon, Wooil-M.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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    • pp.460-464
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    • 2002
  • Multitemporal interferometric SAR has became an useful geodetic tool for monitoring Earth's surface deformation, generation of precise DEM, and land cover classification even though there still exist certain constraints such as temporal and spatial decorrelation effects, atmospheric artifacts and inaccurate orbit information. The Korea where nearly all areas are heavily vegetated, JERS-1 SAR has advantages in monitoring surface deformations and environmental changes in that it uses 4-times longer wavelength than ERS-l/2 or RADARSAT SAR system. For generating differential SAR interferogram and differential coherence image fer deformation mapping and temporal change detection, respectively, topographic phase removal process is required utilizing a reference inteferogram or external DEM simulation. Because the SAR antenna baseline parameter for JERS-1 is less accurate than those of ERS-l/2, one can not estimate topographic phases from an external DEM and the residual phase appears in differential interferogram. In this paper, we examined topographic phase retrieval method utilizing an external DEM. The baseline refinement is carried out by minimizing the differences between the measured unwrapped phase and the reference points of the DEM.

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인간형 로봇의 임팩트 모델과 공기역학을 고려한 축구공의 궤적 계획 (Trajectory Planning of a Soccer Ball Considering Impact Model of Humanoid and Aerodynamics)

  • 소병록;이병주;최재연
    • 제어로봇시스템학회논문지
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    • 제11권1호
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    • pp.58-66
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    • 2005
  • Usual human gait can be modeled as continual impact phenomenon that happens due to the topological change of the kinematic structure of the two feet. The human being adapts his own control algorithm to minimize the ill effect due to the collision with the environment. In order to operate a Humanoid robot like the human being, it is necessary to understand the physics of the impact and to derive an analytical model of the impact. In this paper, specially, we focus on impact analysis of the kicking motion in playing soccer. At the instant of impact, the external impulse exerted on the ball by the foot is an important property. Initially, we introduce the complete external impulse model of the lower-extremity of the human body and analyze the external impulses for several kicking postures of the lower-extremity. Secondly, a trajectory-planning algorithm of a ball, in which the initial velocity and the launch angle of the ball are calculated for a desired trajectory of the ball, will be introduced. The aerodynamic effect such as drag force and lift force is also considered. We carry out numerical simulation and experimentation to verify the effectiveness of the proposed analytical methodology.

아토피 피부염 환자에서 칠엽담(七葉膽)을 함유한 화장품의 임상적 연구 (A Clinical study of Atopic Dermatitis treated by external application with Gynostemma Pentaphyllum MAKINO in cosmetics)

  • 황순이;황보민;지선영;김소연;권영규;서정철
    • 한방안이비인후피부과학회지
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    • 제20권3호
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    • pp.212-221
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    • 2007
  • Objectives : This study was conducted to test patients with Atopic Dermatitis by external application with Gynostemma Pentaphyllum MAKINO in cosmetics. Methods : We gave scores to 59 patients who visited the Dept. of Oriental Medical Opthalmology & Otolaryngology & Dermatology of Daegu Hanny Oriental Medical Center from July 1st, 2005 to December 31th. We checked the clinic index score(extent. intensity : the degree of erythema, induration or papulation, puritus, excorination, lichenification, scaling or dryness, erosion or oozing or weeping. the degree of itching), Eosinophil count and IgE. Results : There are 46 patients we could check by clinic index score, and 44 patients by laboratory. 1. In the 46 cases clinic index score was significantly decreased between the before- and afterexternal application treatment periods(P<0.01). 2. The 46 cases was devided into two types (moist heat type and blood dryness type) by intensity. External application of Gynostemma Pentaphyllum MAKINO in cosmetics did not significant change by two types. 3. In the 44 laboratory cases, the number of eosinophil counts was decreased but the number of IgE was significantly increased. Conclusions : Considering the above results, we have concluded that cosmetics with Gynostemma Pentaphyllum MAKINO have the remedical effect for Atopic Dermatitis.

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담수산어류의 혈청단백질에 미치는 환경수의 영향(I) (The Effect of External Medium on Serum Protein of Fresh Water Fish(I))

  • 이용억;김익태
    • 한국동물학회지
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    • 제8권2호
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    • pp.28-32
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    • 1965
  • It is well known that many kinds of chemical or metalic agent which were ionized or undissociated at toxified external medium and remarkable effect occurred to the fresh water fish. The effects of hydrogen ion concentration on serum protein of fresh water fish, (phycephalus argus CANTOR) had not been reported yet. In this point, authors attempted to study the changes of A/G ratio, total protein, hemoglobin, hematocrit, RBC , liver and kidney weight of snake head in the above environment. 95 snake heads were subjected to external medium with PH-4.5 and A/G ratio, hematocrit, hemoglobin, total protein, RBC, and liver & kidney weight were measured at 32.80, 15202000 and 272 hours respectively. In whole experimental period, L 1 and L2 globulin increased, on the other, albumin decreased as compare with control . Hence, the A/G ratio decreased remarkably . Though, total protein increased prominently through the whole experimental period, hematocrit, hemoglobin, RBC, increased only at 80 hours, and then decreased as compared to the control. Liver weight revealed distinctive increase at 80 hours, but no remarkable change could be seen there after. Hence, kidney weight revealed continuous rise. By these results, it may be said that as snake head were subjected to external medium with PH-4.5, this environmental factor influenced protein metabolism , blood component and organs.

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외부 회로가 연결된 압전 세라믹을 이용한 복합재 보의 수동 감쇠 개선 (Passive Damping Enhancement of Composite Beam Using Piezo Ceramic Connected to External Electrical Networks)

  • 양승만;김도형;한재홍;이인
    • Composites Research
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    • 제12권2호
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    • pp.1-9
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    • 1999
  • 외부 회로가 연결된 압전 재료는 외부 회로의 영향으로 진동수에 영향을 받는 강성(stiffness)과 손실 계수(loss factor)를 가지게 된다. 일반적으로 외부 회로는 두 종류로 구별이 된다. 저항만으로 구성된 경우와 저항과 인덕터(inductor)로 구성된 경우이다. 저항만으로 구성된 경우를 RES(resistive shunting)라 하는데, 이 경우는 압전 재료의 물성이 점탄성 물질과 비슷하게 진동수에 영향을 받는다. 그러나 점탄성 물질에 비해서 더 큰 강성을 지니고, 온도에 영향을 덜 받는다. 저항과 인덕터로 구성된 경우를 RSP(resonant circuit shunting)라 하는데, PMD(proof mass damper)와 비슷한 방법으로 구조물의 공진을 최적으로 조절할 수 있다. 본 논문에서는 이러한 외부 회로와 연결된 압전 재료를 이용하여 복합재 보의 진동을 수동적으로 제어하는 실험을 수행하여 그 결과를 제시하였다.

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원자로용기 외벽냉각시 원자로공동에서 이상유동 자연순환 해석 (Analysis of Two Phase Natural Circulation Flow in the Reactor Cavity under External Vessel Cooling)

  • 박래준;하광순;김상백;김희동
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 춘계학술대회
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    • pp.2141-2145
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    • 2004
  • As part of study on thermal hydraulic behavior in the reactor cavity under external vessel cooling in the APR (Advanced Power Reactor) 1400, one dimensional two phase flow of steady state in the reactor cavity have been analyzed to investigate a coolant circulation mass flow rate in the annulus region between the reactor vessel and the insulation material using the RELAP5/MOD3 computer code. The RELAP5/MOD3 results have shown that a two phase natural circulation flow of 300 - 600 kg/s is generated in the annulus region between the reactor vessel and the insulation material when the external vessel cooling has been applied in the APR 1400. An increase in the heat flux of the inner vessel leads to an increase of the coolant mass flow rate. An increase in the coolant outlet area leads to an increase in the coolant circulation mass flow rate, but the coolant inlet area does not effective on the coolant circulation mass flow rate. The change of the lower coolant outlet to a lower position affects the coolant circulation mass flow rate, but the variation trend is not consistent.

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인듐틴옥사이드와 몰리브데늄을 이용한 외부 기준 저항이 필요 없는 온도센서 (Temperature sensor without reference resistor by indium tin oxide and molybdenum)

  • 전호식;배병성
    • 센서학회지
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    • 제19권6호
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    • pp.483-489
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    • 2010
  • Display quality depends on panel temperatures. To compensate it, temperature sensor was integrated on the panel. The conventional temperature sensor integrated on the panel needs external reference resistor. Since the resistance of external resistor can vary according to the variation of the environment temperature, the conventional temperature sensor can make error in temperature sensing. The environmental temperatures can change by the back light unit, driving circuits or chips. In this paper, we proposed a integrated temperature sensor on display panel which does not need external reference resister. Instead of external reference resistor, we used two materials which have different temperature coefficient in resistivity. They are connected serially and the output voltage was measured at the point of connection with the applied voltage to both ends. The proposed sensor was fabricated with indium tin oxide(ITO), and Mo metal electrode temperature sensor which were connected serially. We verified the temperature senor by the measurements of sensitivity, lineality, hysteresis, repeatability, stability, and accuracy.

건축물의 화재안전설계를 위한 각국의 내·외장재 기준 비교 연구 (Comparative Study on the Standards of Internal and External Materials of Each Country for Fire Safety of Buildings)

  • 허예림;김윤성;이병흔;권영진
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2021년도 봄 학술논문 발표대회
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    • pp.170-171
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    • 2021
  • In Korea, the concentration of cities has led to the high-rise and deep-rise of buildings. In the case of such high-rise buildings, there is a high risk of fire, and the number of internal fires expanding to the outside continues to increase. The Korean Building Act continues to change the ban on combustible exterior materials, and combustible exterior materials are currently not available for buildings with three stories or more than 9 meters, and detailed test standards for finishing materials are also strengthened after the Ulsan residential and commercial fires in 2020. However, the path of fire in the actual building is through a series of processes in which the fire in the compartment grows internally and expands through openings supplied with ventilation factors. Therefore, other than just external materials, design criteria for embedded materials also need to be established. The purpose of this study is to compare standards for internal and external materials at home and abroad and to secure basic data for fire safety design of buildings based on them.

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Design analysis and simulation of an external helical gear

  • Jinlong Yang;Kwang-Hee Lee;Chul-Hee Lee
    • 드라이브 ㆍ 컨트롤
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    • 제20권4호
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    • pp.45-53
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    • 2023
  • This study optimized the parameters of the helical gear based on the original external meshing helical gear pump, combined with the analysis of the stability and flow of the basic parameters of the equipment; herringbone gears were used to eliminate the axial force generated by the helical gears. An optimized helical gear rotor was built with NX. The error between the simulation and calculation results of pump displacement was 3.95% and the simulation results were valid. Analysis of the outlet pressure and lift changes (maximum change rates of 0.38% and 0.25%), pressure analysis of the XY center plane at different times in the same cycle (no pressure surge or drop), and analysis of the axial force of the primary and driven rotors (axis The axial force is close to 0) were performed. The results showed that the flow pulsation of the external gear pump was slight, the operation was smooth, vibration and friction were reduced, the wear of bearings and other components could be diminished, and the service life of the equipment was extended. The simulation results showed that the external gear pump met the design requirements.

외부강선으로 긴장된 PSC 거더의 비선형 해석 (Nonlinear Analysis of PSC Girders with External Tendons)

  • 최규천;이재석
    • 한국전산구조공학회논문집
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    • 제23권3호
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    • pp.303-314
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    • 2010
  • 이 논문에서는 외부강선으로 긴장된 PSC 거더의 비선형 해석방법에 대한 연구를 수행하였다. 외부강선은 정착부와 편향부에서만 부재와 일체로 거동을 하고 정착부-편향부, 편향부-편향부 사이에서 독립적인 거동을 보이는 특성으로 인해 구조물의 처짐이 증가할 경우 부재와 외부강선의 편심량이 감소하여 모멘트가 변화하는 2차 효과(secondary effect)가 발생한다. 또한 편향부에서 외부강선의 인장력 차이로 인해 슬립(slip)이 발생할 경우 외부강선의 인장력이 재분배되어 복잡한 비선형 거동을 보이게 된다. 이 논문에서는 정착부-편향부, 편향부-편향부 사이의 외부강선을 여러 개의 곡선요소로 모사하고, 편향부에서의 마찰력과 driving force(미끄러지는 힘)의 평형관계를 이용하여 외부강선의 인장력을 재분배함으로써 편향부에서의 슬립효과를 고려하였다. 이 논문에서 제시한 외부강선의 유한요소모델과 해석방법을 저자들이 개발한 시공단계를 고려한 PSC 뼈대의 비선형 해석 프로그램에 통합하고, 외부강선으로 긴장된 PSC 보의 해석에 적용하여 외부강선에 대한 유한요소모델 및 해석방법의 정당성과 적용성을 확인하였다. 또한 편향부의 수와 편향부에서의 마찰계수에 따른 극한거동을 검토해본 결과, 편향부의 수가 증가할수록 PSC 보의 항복하중과 극한하중은 증가하였으며, 편향부에서의 마찰계수에 따른 극한거동은 외부강선과 편향부 사이의 마찰력으로 인해 부재에 전달되는 모멘트의 영향에 따라 마찰계수가 적정한 값일 경우에 극한내력이 최대치를 보이는 것을 확인하였다.