• Title/Summary/Keyword: inaccuracy

Search Result 453, Processing Time 0.027 seconds

High-Resolution Image Reconstruction Considering the Inaccurate Sub-Pixel Motion Information (부정확한 부화소 단위의 움직임 정보를 고려한 고해상도 영상 재구성 연구)

  • Park, Jin-Yeol;Lee, Eun-Sil;Gang, Mun-Gi
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.38 no.2
    • /
    • pp.169-178
    • /
    • 2001
  • The demand for high-resolution images is gradually increasing, whereas many imaging systems have been designed to allow a certain level of aliasing during image acquisition. Thus, digital image processing approaches have recently been investigated to reconstruct a high-resolution image from aliased low-resolution images. However, since the sub-pixel motion information is assumed to be accurate in most conventional approaches, the satisfactory high-resolution image cannot be obtained when the sub-pixel motion information is inaccurate. Therefore, in this paper we propose a new algorithm to reduce the distortion in the reconstructed high-resolution image due to the inaccuracy of sub-pixel motion information. For this purpose, we analyze the effect of inaccurate sub-pixel motion information on a high-resolution image reconstruction, and model it as zero-mean additive Gaussian errors added respectively to each low-resolution image. To reduce the distortion we apply the modified multi-channel image deconvolution approach to the problem. The validity of the proposed algorithm is both theoretically and experimentally demonstrated in this paper.

  • PDF

Application of Sediment Transport Model Using Observed Erosion Rates (침식률 측정결과를 사용하는 유사이동모형의 적용)

  • Jung, Tae-Sung;Craig, Jones;Lick, Wilbert
    • Journal of Korea Water Resources Association
    • /
    • v.37 no.12
    • /
    • pp.1033-1041
    • /
    • 2004
  • A 2-dimensional numerical sediment transport model using erosion rates in undisturbed conditions has been developed and applied to calculating the suspended sediment concentrations and bed level changes in the Lower Fox River The model reduces inaccuracy of sediment model by using the accurate erosion rates obtained in a flume (called Sedflume). The flume has been developed to measure erosion rates as a function of sediment depth and at the situation of high shear stresses such as flood event. Both mechanisms of suspended load and bedload transport are included in the model. The model results were verified for the description of sediment transport in a straight channel and the sediment transport during flood event in the Lower Fox River The results of Lower Fox River simulation showed good agreements with the observed SS concentrations. This model can be used to simulate sediment transport under the high shear conditions such as flood.

Development of Horizontal Displacement Sensor for Rainfall-simulated Centrifugal Model Test (강우재현 원심모형실험에 적용하기 위한 수평변위 계측장치의 개발)

  • Lee, Chungwon;Park, Sungyong;Kim, Yongseong
    • Journal of the Korean GEO-environmental Society
    • /
    • v.15 no.12
    • /
    • pp.71-77
    • /
    • 2014
  • Heavy rainfall induces many disasters including slope failure and infrastructure collapse. In this point of view, rainfall-simulated centrifugal model test can be a reasonable tool to evaluate the stability of geotechnical structure. In order to obtain the displacements of a model in centrifugal model test, in general, LVDT and laser displacement sensor are used. However, when the rainfall is simulated, the LVDT has the problem of excessive infiltration into the model ground, and the laser displacement sensor provides the measuring result with inaccuracy due to the dispersion of the laser radiation. Hence, in this study, horizontal displacement sensor for rainfall-simulated centrifugal model test was developed. This sensor produced with a thin elastic steel plate and gave the accurate relationship between the displacement and the strain.

Evaluation of the Smear Zone by Numerical Analysis Method (수치해석에 의한 스미어 존 평가)

  • Kang, Yun;Nam, Yelwoo;Lee, Seombeom;Kim, Hongtaek
    • Journal of the Korean GEO-environmental Society
    • /
    • v.8 no.3
    • /
    • pp.35-40
    • /
    • 2007
  • The vertical drain method recently being used in Korea is divided into the sand drain method, the pack drain method, the paper drain method, and the PBD method according to the drainage. However, these methods generate the disturbed zone called the smear zone when the drainage is penetrated into the in-situ ground. The characteristics of the smear zone generated cause the problems that the coefficient of permeability decreases and the consolidation time becomes longer than expected in the design. Although the size of the smear zone is a very important factor directly influencing the degree of consolidation, in the existing studies, the general value for the size of the smear zone proposed has been used in the design. However, the size of the smear zone proposed by the existing studies cause a loss of economical efficiency because of the inaccuracy of the design. Hence, in this study, the characteristics on the size of the smear zone were analyzed by carrying out the three dimensional numerical analysis and the method to determine the conversion size of the smear zone considering the change of the coefficient of permeability was proposed in order to consider the change of the coefficient of permeability in the actual design.

  • PDF

A Study on the Efficiency of Hydrogen-Oxygen Mixture Gas Generation Stack (수소-산소 혼합가스 발생 스택의 효율 연구)

  • Lee, Sang-Ho;Moon, Il-Sik;Kim, Chang-Hee;Kang, Kyoung-Soo;Park, Chu-Sik;Bae, Ki-Kwang
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.17 no.4
    • /
    • pp.409-417
    • /
    • 2006
  • The characteristics of hydrogen-oxygen mixture gas generation stack was experimentally studied in terms of efficiency. For this purpose, the mixture gas generation stack was fabricated by connecting 7 cells in series following the Tero Ranta report. In order to avoid the instrument inaccuracy, all measuring equipments were re-tested and calibrated by Korea Laboratory Accreditation Scheme (KOLAS) certified laboratories. Since the amount of produced gas is most crucial in determining the efficiency, two gas collecting methods such as bottle trap method and wet gas meter method were adopted. From the experimental results, it was found that both KOH fume and steam evaporated along with hydrogen-oxygen mixture gas, and these by-product gases could cause the misestimation of the stack efficiency. The current, voltage, and energy efficiencies of the hydrogen-oxygen mixture gas generation stack was evaluated based upon the stack efficiency calculation method summarized in this work.

Study on validating proper System Requirements by using Cost Estimations Methodology (비용추정방법을 활용한 시스템요구사항 적정성 확인방안 연구)

  • Choi, Sung Kyu;Choi, Eun Ha
    • Convergence Security Journal
    • /
    • v.13 no.5
    • /
    • pp.97-105
    • /
    • 2013
  • It is very important the government project should be supported by enough budget for proceeding. The insufficient budget by poor budget estimating uesd to bring about discontinuing for the project. This is originally caused by inaccuracy for cost estimating about system and evaluating for system requirements on the projet initial phase. The system requirements is technical requirements that converted the user needs and is needs for communicating between stakeholder and developer and manufacturer. Also the system requirements is the primary factor to make the project cost. The cost estimating is not easy due to complication of cost factors and an aberration between cost estimating and actual cost. Specially, on the project initial phase, shortage of detail information for project make more difficult to do cost estimating. This study proposes the architecture for validating proper system requirements by using cost estimations methodology on the project initial phase and shows the computer tool for simulating the proposed architecture.

The Study on Improving Accuracy of Land Cover Classification using Spectral Library of Hyperspectral Image (초분광영상의 분광라이브러리를 이용한 토지피복분류의 정확도 향상에 관한 연구)

  • Park, Jung-Seo;Seo, Jin-Jae;Go, Je-Woong;Cho, Gi-Sung
    • Journal of Cadastre & Land InformatiX
    • /
    • v.46 no.2
    • /
    • pp.239-251
    • /
    • 2016
  • Hyperspectral image is widely used for land cover classification because it has a number of narrow bands and allow each pixel to include much more information in comparison with previous multi-spectral image. However, Higher spectral resolution of hyperspectral image results in an increase in data volumes and a decrease in noise efficiency. SAM(Spectral Angle Mapping), a method based on vector inner product to compare spectrum distribution, is a highly valuable and popular way to analyze continuous spectrum of hyperspectral image. SAM is shown to be less accurate when it is used to analyze hyperspectral image for land cover classification using spectral library. this inaccuracy is due to the effects of atmosphere. We suggest a decision tree based method to compensate the defect and show that the method improved accuracy of land cover classification.

Alberti's Theory of Architectural Design and Vitruvius (알베르티의 건축 설계론과 비트루비우스)

  • Cho, Eun-Jung
    • The Journal of Art Theory & Practice
    • /
    • no.9
    • /
    • pp.195-215
    • /
    • 2010
  • Alberti's De re aedificatoria is the earliest case in the history of Italian Renaissance architectural treatises dealing with recovery of antiquity through textual and archaeological pursuits. The key source of the Renaissance theoreticians was Vitruvius' De architectura. However, Alberti was keenly aware of inaccuracy and Hellenization of Latinity in this classical text, and tried to compensate them in his own treatise. Furthermore he claimed a reformed discipline of the architects as well as the patrons, and prescribed how future buildings and cities should be built, based on the proper authority of ancient architecture in proper and intelligible Latin. Such an adaptation of classical usage in order to reestablish a modern norm preceded in his earlier work Momus, a satire on the contemporary Italian society of his own by following the model of Lucian. Alberti's suggestion of proper government in Momus's phrase was expanded in De re aedificatoria, for he consider the buildings are subject to the rules of morality and public interests. He proclaimed that the nature of beauty is the reasoned harmony of every part within a body, and architectural beauty also lies on the harmonized arrangement of all the elements within an individual building and of all individual buildings and facilities within a city. For the architects to execute this task, he formulated the concept of lineanenta, the form derived from the mind in order to prescribe the proper place, numbers, scale, and orders for whole building structure. It is the future oriented city-plans and building designs to serve the public interest and the good of all the individual citizens who make up the City-State that Alberti pursued in his treatise.

  • PDF

Text extraction in images using simplify color and edges pattern analysis (색상 단순화와 윤곽선 패턴 분석을 통한 이미지에서의 글자추출)

  • Yang, Jae-Ho;Park, Young-Soo;Lee, Sang-Hun
    • Journal of the Korea Convergence Society
    • /
    • v.8 no.8
    • /
    • pp.33-40
    • /
    • 2017
  • In this paper, we propose a text extraction method by pattern analysis on contour for effective text detection in image. Text extraction algorithms using edge based methods show good performance in images with simple backgrounds, The images of complex background has a poor performance shortcomings. The proposed method simplifies the color of the image by using K-means clustering in the preprocessing process to detect the character region in the image. Enhance the boundaries of the object through the High pass filter to improve the inaccuracy of the boundary of the object in the color simplification process. Then, by using the difference between the expansion and erosion of the morphology technique, the edges of the object is detected, and the character candidate region is discriminated by analyzing the pattern of the contour portion of the acquired region to remove the unnecessary region (picture, background). As a final result, we have shown that the characters included in the candidate character region are extracted by removing unnecessary regions.

Determination of the Elbow Transverse Joint Using the Helical Axis Concept and its Application to the Development of a Kinematic Arm Model (나선축 개념을 이용한 팔꿈치 관절의 3차원 회전축 측정과 측정 결과를 반영한 인체 팔 모델의 개발)

  • Woo, Bum-Young;Jung, Eui-S.;Yun, Myung-Hwan
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.26 no.1
    • /
    • pp.73-80
    • /
    • 2000
  • To determine the exact direction and location of the human joint in motion is crucial in developing a more accurate human model and producing a more fitting artificial joint. There have been several reports on the biomechanical analysis of the joint to determine the anatomy and movement of joints. However, all the previous researches were made in vitro study, that is, they investigated the passive movement of the joint from cadavers and the suggested location of the joint axis was difficult to make practical applications due to the lack of the direction of joint axis. Also, in many biomechanical models, each joint axis is assumed to lie horizontally or vertically to the adjacent links. Such an assumption causes inherent inaccuracy. In this study, the direction and location of the transverse elbow axis was obtained with respect to the global coordinate system whose origin is on the lateral epicondyle of the humerus. The suggested result based on the global coordinate system lying on the external landmark will be helpful to understand the information of the axis and to make an application. From the experiments conducted for five subjects, the direction and location of the elbow transverse joint was determined for each subject by the helical axis method. A statistical validation was also performed to confirm the result. Finally, the result was applied to develop a simple elbow model which is a part of the kinematic arm model. The simple elbow movement model was developed to validate the significance of the result and the kinematic arm model was able to describe the geometry of any complex linkage system. As a result, the errors incurred from the proposed model were significantly reduced when compared to the ones from the previous approach.

  • PDF