• Title/Summary/Keyword: 오차계

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A Mechanics-Based Determination of Heating Lines in Line Heating Process (열변형 해석 기구를 통한 선상 가열에서의 가열선 수정에 관한 연구)

  • Yong-Gyun Kim;Jong-Gye Shin
    • Journal of the Society of Naval Architects of Korea
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    • v.39 no.2
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    • pp.45-51
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    • 2002
  • In Line Heating method, heating line is determined by kinematics analysis. But the heating line, which is solved by kinematics analysis, doesn't verify by the point of physical analysis and the choice problem in many heating line doesn't determine. In this paper, the simulator is developed. When we get the processing information at the kinematics analysis, simulator can estimate the shape of deformed plate that process along the processing information. When we get the initial shape and the object shape, we calculate the processing information first, using kinematics analysis. In a simulator, we estimate deformed shape from the processing information. After this we compare deformed shape and object shape. If the error of deformed shape and object shape is in the proper limits, that information is determined the final processing information. Else we repeat the process changing variables.

Estimating Bathroom Water-uses based on Time Series Regression (시계열 회귀모형에 기초한 욕실 내 용수 사용량 추정)

  • Myoung, Sungmin;Kim, Donggeon;Jo, Jinnam
    • Journal of the Korea Society of Computer and Information
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    • v.19 no.8
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    • pp.19-26
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    • 2014
  • Analysis of influential factors on water consumption in households will help predicting the water demand of end-use in household and give an explanation to cause on the change of trend. In this research, the data are gathered by radio telemetry system which is combined electronic flow-meter and wireless communication system in 140 household in Korea. Using this data, we estimate for each residential type to determine liter per capita day. we used real data to predict bathtub and washbowl water-uses and compared the ordinary least square regression model and autoregressive regression error model. The results of this study can be applied in the planning stages of water and waste water facilities.

Fluorescent Pattern Generation on the Fluorescent Photopolymer with 2-beam Coupling Method (2-beam Coupling 방법을 이용한 광 고분자 형광 패턴 형성)

  • Kim, Yoon-Jung;Kim, Jeong-Hun;Sim, Bo-Yeon;Lee, Myeong-Kyu;Kim, Eun-Kyoung
    • Korean Journal of Optics and Photonics
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    • v.21 no.1
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    • pp.6-11
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    • 2010
  • Fluorescent photopolymer film was prepared with composition containing acrylate monomer, binder, a visible light sensitive photo initiator, and fluorescent anthracene polymer. A fluorescent grating pattern was inscribed on the photopolymer film using a 2-beam coupling method. A 514 nm laser was coupled to generate a beam-interference pattern. A highly fluorescent diffractive line pattern was formed on the fluorescent photopolymer within 30 sec. of exposure. The fluorescence intensity was highly enhanced in the patterned area, possibly due to the change in the environment of the fluorescent polymers by the photo-polymerization of monomers. Under a photo-mask, a gap electrode pattern was formed of fluorescent gratings with a sub-micron scale, which was matched well to the calculated value ($2.5\;{\mu}m$ and $0.6\;{\mu}m$) based on the refractive index of the photopolymer and beam incident angle ($3.4^{\circ}$, $15^{\circ}$) to the photopolymer surface.

Tracking Control System Design for the Transfer Crane : Design of Full-order Observer with Weighted $H_{\infty}$ Error Bound (트랜스퍼 크레인의 이송위치제어를 위한 서보계 설계 : 가중 $H_{\infty}$ 오차사양을 만족하는 동일차원 관측기 설계)

  • Kim, Y.B.;Jeong, H.H.;Yang, J.H.
    • Journal of Power System Engineering
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    • v.12 no.6
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    • pp.42-49
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    • 2008
  • The most important job in the container terminal area is to handle the cargo effectively in the limited time. To achieve this object, many strategies have been introduced and applied to. If we consider the automated container terminal, it is necessary that the cargo handling equipments are equipped with more intelligent control systems. From the middle of the 1990's, an automated rail-mounted gantry crane(RMGC) and rubber-tired gantry crane(RTG) have been developed and widely used to handle containers in the yards. Recently, in these cranes, the many equipments like CCD cameras and sensors are mounted to cope with the automated terminal environment. In this paper, we try to support the development of more intelligent automated cranes which make the cargo handling be performed effectively in the yards. For this plant, the modelling, tracking control, anti-sway system design, skew motion suppressing and complicated motion control and suppressing problems must be considered. Especially, in this paper, the system modelling and tracking control approach are discussed. And, we design the tracking control system incorporating an observer based on the 2DOF servo system design approach to obtain the desired state informations. In the case of observer design, a weighted $H_{\infty}$ error bound approach for a state estimator is considered. Based on an algebraic Riccati equation(inequality) approach, a necessary and sufficient condition for the existence of a full-order estimator which satisfies the weighted $H_{\infty}$ error bound is introduced. Where, the condition for existence of the estimator is denoted by a Linear Matrix Inequality(LMI) which gives an optimized solution and observer gain. Based on this result, we apply it to the tracking control system design for the transfer crane.

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Monte Carlo Simulation for absorbed dose in PMMA phantom during the low-energy X-ray irradiation (저 에너지 X선 조사 시 PMMA 팬텀 내의 흡수선량 평가를 위한 몬테카를로 시뮬레이션)

  • Kim, Sang-Tae;Kang, Sang-Koo;Kim, Chong-Yeal
    • Journal of the Korean Society of Radiology
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    • v.5 no.6
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    • pp.383-389
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    • 2011
  • This study offered a new method to calculate absorbed dose of actual patients through Monte Carlo Simulation by using the linkage of Geant4 and DICOM, and, the experimental value of absorbed dose at the center and Geant 4 simulation result according to the depth of PMMA mock phantom were compared by using MOSEF in order to verify Geant4 calculation code. In the area where there was no air space between the irregular gap due to incomplete compression of PMMA slab, the differences were $0.46{\pm}4.69$ percent and $-0.75{\pm}5.19$percent in $15{\times}15cm^2$ and $20{\times}20cm^2$ respectively. Excluding the error due to incomplete compression of PMMA mock phantom, the calculation values of the Monte Carlo simulation by linkage of Geant4 and DICOM was the same.

Study on the Scap-cure Behavior of Adhesive for Flip-chip Bonding (플립칩 본딩용 접착제의 속경화 거동 연구)

  • Lee, Jun-Sik;Min, Kyung-Eun;Kim, Mok-Sun;Lee, Chang-Woo;Kim, Jun-Ki
    • Proceedings of the KWS Conference
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    • 2010.05a
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    • pp.78-78
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    • 2010
  • 모바일 정보통신기기를 중심으로 패키지의 초소형화, 고집적화를 위해 플립칩 공법의 적용이 증가되고 있고 있으며 접속피치의 미세화에 따라 솔더 및 언더필을 사용하는 C4 공법보다 ACA(Anisotropic Conductive Adhesive), NCA (Non-conductive Adhesive) 등의 접착제를 이용하는 칩본딩 공법에 대한 요구가 증가하고 있다. 특히, NCA 공법의 경우 산업 현장의 대량생산에 대응하기 위해서는 접착제의 속경화 특성이 요구되어 진다. 일반적으로 접착제의 경화거동은 DSC(Differential Scanning Calorimeter)를 사용해 확인하지만, 수초 이내에 경화되는 접착제의 경우는 적용되기 어렵다. 본 연구에서는 이러한 전자패키지용 접착제의 속경화 거동을 효과적으로 평가할 수 있는 방법을 조사 하였다. 실험에서 사용된 접착제는 에폭시계 레진 기반에 이미다졸계 경화제를 사용한 기본적인 포뮬레이션을 사용하였고, 경화시간은 160^{\circ}C에서 1분 이내에 경화되는 특성을 가지고 있다. 경화 거동을 확인하기 위해서 isothermal DSC와 DEA(Dielectric Analysis)의 두가지 방법을 사용해 비교하였다. 두 실험 방법 모두 $160^{\circ}C$를 유지하며 경화 거동을 확인하였고, DoC(Degree of Cure)의 측정오차를 비교 분석하였다. DEA는 이온 모빌리티 변화에 따른 유전손실율을 측정하는 방법으로 80~90% 이후의 경화도는 측정되지 않았지만, 수초 이내에 경화되는 속경화 특성을 평가하기에 적합한 것으로 확인되었다.

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Influence of Sensor Noise on the Localization Error in Multichannel SQUID Gradiometer System (다채널 스퀴드 미분계에서 센서 잡음이 위치추정 오차에 미치는 영향)

  • 김기웅;이용호;권혁찬;김진목;정용석;강찬석;김인선;박용기;이순걸
    • Progress in Superconductivity
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    • v.5 no.2
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    • pp.98-104
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    • 2004
  • We analyzed a noise-sensitivity profile of a specific SQUID sensor system for the localization of brain activity. The location of a neuromagnetic current source is estimated from the recording of spatially distributed SQUID sensors. According to the specific arrangement of the sensors, each site in the source space has different sensitivity, that is, the difference in the lead field vectors. Conversely, channel noises on each sensor will give a different amount of the estimation error to each of the source sites. e.g., a distant source site from the sensor system has a small lead-field vector in magnitude and low sensitivity. However, when we solve the inverse problem from the recorded sensor data, we use the inverse of the lead-field vector that is rather large, which results in an overestimated noise power on the site. Especially, the spatial sensitivity profile of a gradiometer system measuring tangential fields is much more complex than a radial magnetometer system. This is one of the causes to make the solutions of inverse problems unstable on intervening of the sensor noise. In this study, in order to improve the localization accuracy, we calculated the noise-sensitivity profile of our 40-channel planar SQUID gradiometer system, and applied it as a normalization weight factor to the source localization using synthetic aperture magnetometry.

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Construction Stage Analysis of Cable-Stayed Bridges Using the Unstrained Element Length Method (무응력길이법을 이용한 사장교의 시공단계 해석)

  • Park, Se Woong;Jung, Myung Rag;Min, Dong Ju;Kim, Moon Young
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.36 no.6
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    • pp.991-998
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    • 2016
  • The propose of this study is to demonstrate how efficiently and accurately the construction stages of cable-stayed bridges are analyzed using the unstrained length method (ULM) in which all unstrained element lengths are determined from a simplified analytical method (Jung et al., 2015). A forward analysis of cable-stayed bridges using the commercial FEA program, MIDAS is sequentially carried out considering the lack of fit force but the ULM is able to analyze a intermediate construction stage directly by taking the corresponding unstrained lengths of the construction stage model simply. The closing load step analysis is achieved by loading the pavement and counter weight forces in reverse. An Incheon bridge model is analyzed using the present ULM and the commercial program, respectively, and the two analysis results are compared.

3D Shape Reconstruction of Non-Lambertian Surface (Non-Lambertian면의 형상복원)

  • 김태은;이말례
    • Journal of Korea Multimedia Society
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    • v.1 no.1
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    • pp.26-36
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    • 1998
  • It is very important study field in computer vision 'How we obtain 3D information from 2D image'. For this purpose, we must know position of camera, direction of light source, and surface reflectance property before we take the image, which are intrinsic information of the object in the scene. Among them, surface reflectance property presents very important clues. Most previous researches assume that objects have only Lambertian reflectance, but many real world objects have Non-Lambertian reflectance property. In this paper the new method for analyzing the properties of surface reflectance and reconstructing the shape of object through estimation of reflectance parameters is proposed. We have interest in Non-Lambertian reflectance surface that has specular reflection and diffuse reflection which can be explained by Torrance-Sparrow model. Photometric matching method proposed in this paper is robust method because it match reference image and object image considering the neighbor brightness distribution. Also in this thesis, the neural network based shaped reconstruction method is proposed, which can be performed in the absence of reflectance information. When brightness obtained by each light is inputted, neural network is trained by surface normal and can determine the surface shape of object.

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A Voltage Disturbance Detection Method for Computer Application Lods (컴퓨터 응용 부하들을 위한 전압 외란 검출 방법)

  • 이상훈;최재호
    • The Transactions of the Korean Institute of Power Electronics
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    • v.5 no.6
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    • pp.584-591
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    • 2000
  • Power Quality Compensator(PQC) has been installed to protect the sensitive loads against the voltage disturbances, such as voltage sag and interruption. In general, static switch is used for the purpose of link between utility and PQC. So transfer operation of the static switch play a important part in the PQC. Many studies on the structure and control of PQC have been progressed in active, but these researches have been rarely mentioned about any voltage-disturbances-detection method to start the PQC operation. In this paper, a new voltage-disturbances-detection algorithm for computer application loads using the CBEMA/ITIC curve is proposed for transfer operation of the static switch. The proposed detection algorithm is implemented to get fast detecting time through the comparison of instantaneous 3-phase voltage values transferred to DC values in the synchronous reference frame with the operating reference values. To get the robust characteristics against the noise, a first order digital filter is designed. The magnitude falling and phase delay caused by the filter are compensated through the error normalizing and numerical analysis using transfer function, respectively. Finally, the validity of the proposed algorithm is proved by ACSL simulation and experimental results.

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