• Title/Summary/Keyword: Shadow Remove

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A Study on the Performance Digital Beamforming using Antenna Error Correction and Modified Optimum Weight for Improved Signal Estimation (향상된 신호 추정을 위한 안테나 오차 보정 과 수정된 최적 가중치를 이용한 디지털 빔 형성 성능 분석에 관한 연구)

  • Cho, Sung Kuk;Lee, Jun Dong;Yang, Gill Mo
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.10 no.4
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    • pp.63-70
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    • 2014
  • Method a target estimation in spatial are mobile wireless communication using network cell and GPS. It have much error that mobile wireless communication depend on cell size. GPS method can't find a target in shadow and inner area. In this paper, we estimate a target as direction of arrival method using adaptive array antenna system. Adaptive array antenna system can obtain desired signal to remove other signal This paper studied digital beamforming method in order to estimation a target. Proposed method is modified optimum weight and antenna error correction to estimation an optimal receive signal. Digital beamforming method decided a signal phase and amplitude from received signal on array antenna element. But if it is not to do error correction of received signal, system performance have decreased. Firstly, we proposed modified optimum weight in order to finding desired target. Secondly, we are error correction of antenna incident signals by optimal weight before digital beamforming method. Thirdly, throughly simulation, we showed that system performance of proposed method compare proposal method with general method. It have improved resolution of estimation target to good performance more proposed method than general method.

Generation of DEM by Correcting Blockage Areas on ASTER Stereo Images (ASTER 스테레오 영상의 폐색영역 보정에 의한 DEM 생성)

  • Lee, Jin-Duk;Park, Jin-Sung
    • Journal of the Korean Association of Geographic Information Studies
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    • v.13 no.1
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    • pp.155-163
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    • 2010
  • The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on-board the NASA's Terra spacecraft provides along-track digital stereo image data at 15m resolution with a base-height ratio 0.6. Automated stereocorrelation procedure was implemented using the ENVI 4.1 software to derive DEMs with $15m{\times}15m$ in 43km long and 50km wide area using the ASTER stereo images. The accuracy of DEMs was analyzed in comparison with those which were obtained from digital topographic maps of 1:25,000 scale. Results indicate that RMSE in elevation between ${\pm}7$ and ${\pm}20m$ could be achieved. Excluding cloud, water and building areas as the factors which make RMSE value exceeding 10m, the accuracy of DEMs showed RMSE of ${\pm}5.789m$. Therefore for the purpose of elevating accuracy of topographic information, we intended to detect the cloud areas and shadow areas by a landcover classification method, remove those areas on the ASTER DEM and then replace with those areas detached from the cartographic DEM by band math.

Diagnosis and Treatment of Bronchial Foreign Body by Ventilating Bronchoscopy (환기형 기관지경술을 이용한 기도내 이물의 진단과 치료)

  • Kim, Beom-Gyu;Kang, Jin-Wook;Kim, Young-Jae;Nam, Soon-Yuhl
    • Korean Journal of Bronchoesophagology
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    • v.8 no.2
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    • pp.36-42
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    • 2002
  • Aspirated and ingested foreign bodies continue to present challenges to otolaryngologists. The major discussions were the accurate diagnosis and speedy, safe removal of foreign body. Many diagnostic tools have been tried and removal of foreign bodies has been facilitated by technical improvements with rod lens telescope, video endoscope, flexible fiberoendoscope and safer anesthesia. In spite of these advances, more than 3000 children's death occur per year in the world because of foreign bodies and untold number of parients survive with variable sequelae. In these study, 59 consecutive cases of children and adults with tracheobronchial foreign bodies were reviewed from 1992 to 2001. We studied the history, symptoms, ausculatory radiologic, bronchoscopic finding and post operative complications. 71% (42 cases in 59 cases) of patients had foreign body aspiration history or choking crisis. In 64% (38cases) cough was observed. 81% (48cases) had abnormal finding in chest auscultation and 78% in chest X-ray. Computed tomography was done in 12 cases, all were founded foreign body shadow. Main site of foreign body was right main bronchus (41%, 24cases) and most frequent foreign body was peanut (36% , 21cases) . 4 experienced ICU(intensive care unit) care. 2 cases were failed to remove foreign. In these cases 1 cases was improved by steroid therapy and physical therapy and the other was treated with thoracotomy. We concluded the morbidity and motality were much correlated with speedy decision making and experienced skill of operator.

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Intracardiac Foreign Body by Penetrating Cardiac Injury (관통성 손상에 의한 심장내 이물 - 수술 치험 1례 -)

  • 정진용
    • Journal of Chest Surgery
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    • v.23 no.5
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    • pp.929-935
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    • 1990
  • Violence in our society, combined with improving transport system, resulted in increased numbers of patients with cardiac wounds reaching the hospital alive. Most patients with penetrating cardiac injury, rather than blunt injury, present with a syndrome of either hemorrhagic shock or cardiac tamponade. And they should be operated upon as soon as possible. Often the atrioventricular valves and other important cardiac structures are also damaged by the penetrating instruments or missile. Both intracardiac communications and atrioventricular fistulas may result in significant left-to-right shunts accompanied by congestive heart failure, necessitating surgical correction. Usually, retained cardiac foreign bodies, which are almost always bullets or fragments of missiles, may lie within a cardiac chamber or in the myocardium. Emboli of bullets or other missiles from distant sites to the right side of the heart are numerous enough to require attention. Recently we experienced a case with intracardiac foreign body due to penetrating cardiac injury. A 19 year-old man was admitted to our hospital due to penetrating anterior chest wound by iron segment. The roentgenogram of the chest revealed a radio-opaque metallic shadow in left lower chest around the cardiac apex, mild blunting of left costophrenic space, but no cardiomegaly. During operation the foreign body was noted to be present in the cardiac chamber by the portable C-arm fluoroscopy. But during the manipulation it moved into left inferior pulmonary vein from left ventricle by way of left atrium. So we could manage to remove it from left inferior pulmonary vein by direct approach to the vein. It was iron segment, sized 0.lcm x0.6cmx0.5cm, with sharp margins. The patient had an uneventful postoperative recovery except for chylopericardium and was discharged.

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Gait Recognition Using Multiple Feature detection (다중 특징점 검출을 이용한 보행인식)

  • Cho, Woon;Kim, Dong-Hyeon;Paik, Joon-Ki
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.44 no.6
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    • pp.84-92
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    • 2007
  • The gait recognition is presented for human identification from a sequence of noisy silhouettes segmented from video by capturing at a distance. The proposed gait recognition algorithm gives better performance than the baseline algorithm because of segmentation of the object by using multiple modules; i) motion detection, ii) object region detection, iii) head detection, and iv) active shape models, which solve the baseline algorithm#s problems to make background, to remove shadow, and to be better recognition rates. For the experiment, we used the HumanID Gait Challenge data set, which is the largest gait benchmarking data set with 122 objects, For realistic simulation we use various values for the following parameters; i) viewpoint, ii) shoe, iii) surface, iv) carrying condition, and v) time.

A Study on High performance Electrical Precipitation Technology for PM Removal in Exhaust Gas (배가스 내 미세먼지 제거를 위한 고성능 집진 기술에 대한 연구)

  • Kim, Soyeon;Kim, Minsung;Choi, Sangmi;Jung, Minkyu;Lee, Jinwook
    • Plant Journal
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    • v.18 no.1
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    • pp.50-54
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    • 2022
  • The demand for high-efficiency dust collectors is rapidly increasing to remove PM from exhaust gas emission facilities, such as thermal power plants, steel mills, and industrial cogeneration plants, as the Pmemission standards have been strengthened. In this study, the electrospray is adapted for existing electrosratic precipitator(EP) to remedy its shortcomings and to improve the performance. Electrospray has been mainly used for the purpose of generating very fine droplets, but fir the purpose of EP, the flow rate over 10 mL/min per nozzleis required, and a high flow rate condition of 65 to 200 times is required. The electrospray of high flow rate has a completely different spray shape from the low flow rate condition, and was visualized through various figures such as corona discharge photographs and shadow images.

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(Distance and Speed Measurements of Moving Object Using Difference Image in Stereo Vision System) (스테레오 비전 시스템에서 차 영상을 이용한 이동 물체의 거리와 속도측정)

  • 허상민;조미령;이상훈;강준길;전형준
    • Journal of the Korea Computer Industry Society
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    • v.3 no.9
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    • pp.1145-1156
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    • 2002
  • A method to measure the speed and distance of moving object is proposed using the stereo vision system. One of the most important factors for measuring the speed and distance of moving object is the accuracy of object tracking. Accordingly, the background image algorithm is adopted to track the rapidly moving object and the local opening operator algorithm is used to remove the shadow and noise of object. The extraction efficiency of moving object is improved by using the adaptive threshold algorithm independent to variation of brightness. Since the left and right central points are compensated, the more exact speed and distance of object can be measured. Using the background image algorithm and local opening operator algorithm, the computational processes are reduced and it is possible to achieve the real-time processing of the speed and distance of moving object. The simulation results show that background image algorithm can track the moving object more rapidly than any other algorithm. The application of adaptive threshold algorithm improved the extraction efficiency of the target by reducing the candidate areas. Since the central point of the target is compensated by using the binocular parallax, the error of measurement for the speed and distance of moving object is reduced. The error rate of measurement for the distance from the stereo camera to moving object and for the speed of moving object are 2.68% and 3.32%, respectively.

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Design and Implementation of the Stop line and Crosswalk Recognition Algorithm for Autonomous UGV (자율 주행 UGV를 위한 정지선과 횡단보도 인식 알고리즘 설계 및 구현)

  • Lee, Jae Hwan;Yoon, Heebyung
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.3
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    • pp.271-278
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    • 2014
  • In spite of that stop line and crosswalk should be aware of the most basic objects in transportation system, its features extracted are very limited. In addition to image-based recognition technology, laser and RF, GPS/INS recognition technology, it is difficult to recognize. For this reason, the limited research in this area has been done. In this paper, the algorithm to recognize the stop line and crosswalk is designed and implemented using image-based recognition technology with the images input through a vision sensor. This algorithm consists of three functions.; One is to select the area, in advance, needed for feature extraction in order to speed up the data processing, 'Region of Interest', another is to process the images only that white color is detected more than a certain proportion in order to remove the unnecessary operation, 'Color Pattern Inspection', the other is 'Feature Extraction and Recognition', which is to extract the edge features and compare this to the previously-modeled one to identify the stop line and crosswalk. For this, especially by using case based feature comparison algorithm, it can identify either both stop line and crosswalk exist or just one exists. Also the proposed algorithm is to develop existing researches by comparing and analysing effect of in-vehicle camera installation and changes in recognition rate of distance estimation and various constraints such as backlight and shadow.

Three-dimensional Machine Vision System based on moire Interferometry for the Ball Shape Inspection of Micro BGA Packages (마이크로 BGA 패키지의 볼 형상 시각검사를 위한 모아레 간섭계 기반 3차원 머신 비젼 시스템)

  • Kim, Min-Young
    • Journal of the Microelectronics and Packaging Society
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    • v.19 no.1
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    • pp.81-87
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    • 2012
  • This paper focuses on three-dimensional measurement system of micro balls on micro Ball-Grid-Array(BGA) packages in-line. Most of visual inspection system still suffers from sophisticate reflection characteristics of micro balls. For accurate shape measurement of them, a specially designed visual sensor system is proposed under the sensing principle of phase shifting moire interferometry. The system consists of a pattern projection system with four projection subsystems and an imaging system. In the projection system, four subsystems have spatially different projection directions to make target objects experience the pattern illuminations with different incident directions. For the phase shifting, each grating pattern of subsystem is regularly moved by PZT actuator. To remove specular noise and shadow area of BGA balls efficiently, a compact multiple-pattern projection and imaging system is implemented and tested. Especially, a sensor fusion algorithm to integrate four information sets, acquired from multiple projections, into one is proposed with the basis of Bayesian sensor fusion theory. To see how the proposed system works, a series of experiments is performed and the results are analyzed in detail.