• Title/Summary/Keyword: Detection techniques

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Illumination-Robust Load Lane Color Recognition based on S-color Space (조명변화에 강인한 S-색상공간 기반의 차선색상 판별 방법)

  • Baek, Seung-Hae;Jin, Yan;Lee, Geun-Mo;Park, Soon-Yong
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.22 no.3
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    • pp.434-442
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    • 2018
  • In this paper, we propose a road lane color recognition method from the image obtained from a driving vehicle. In autonomous vehicle techniques, lane information becomes more important as the level of autonomous driving such as lane departure warning and dynamic lane keeping assistance is increased. In particular the lane color recognition, especially the white and the yellow lanes, is necessary technique because it is directly related to traffic accidents. In this paper, color information of lane and road area is mapped to a 2-dimensional S-color space based on lane detection. And the center of the feature distribution is obtained by using an improved mean-shift algorithm in the S-color space. The lane color is determined by using the distance between the center coordinates of the color features of the left and right lanes and the road area. In various illumination conditions, about 97% color recognition rate is achieved.

A Virtual Sculpting System using Haptic Interface (햅틱 인터페이스를 이용한 가상 조각 시스템)

  • Kim Laehyun;Park Sehyung
    • Journal of KIISE:Computer Systems and Theory
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    • v.31 no.12
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    • pp.682-691
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    • 2004
  • We present a novel haptic sculpting system where the user intuitively adds to and carves out material from a volumetric model using new sculpting tools in the similar way to handling real clay Haptic rendering and model deformation are implemented based on volumetric implicit surface. We enhance previous volume-based haptic sculpting systems by presenting fast and stable force computation on 3D models to be deformed. In order to bridge the gap between fast haptic process (1 KHz) and much slower visual update frequency(~30Hz), the system generates intermediate implicit surfaces between two consecutive physical models being deformed. It performs collision detection and force computation on the intermediate surface in haptic process. The volumetric model being sculpted is visualized as a geometric model which is adaptively polygonized according to the surface complexity. We also introduce various visual effects for the real-time sculpting system including mesh-based solid texturing, painting, and embossing/engraving techniques.

A Technique for Detecting Interaction-based Communities in Dynamic Networks (동적 네트워크에서 인터랙션 기반 커뮤니티 발견 기법)

  • Kim, Paul;Kim, Sangwook
    • KIISE Transactions on Computing Practices
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    • v.22 no.8
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    • pp.357-362
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    • 2016
  • A social network or bio network is one of the complex networks that are formed by connecting specific relationships between interacting objects. Usually, these networks consist of community structures. Automatically detecting the structures is an important technique to understand and control the interaction objects. However, the topologies and structures of the networks change by interactions of the objects, with respect to time. Conventional techniques for finding the community structure have a high computational complexity. Additionally, the methods inefficiently deal with repeated computation concerning graph operation. In this paper, we propose an incremental technique for detecting interaction-based communities in dynamic networks. The proposed technique is able to efficiently find the communities, since there is an awareness of changed objects from the previous network, and it can incrementally reuse the previous community structure.

Development of Automatic Crack Detection System for Concrete Structure Using Image Processing Method (이미지 분석기법을 이용한 콘크리트 구조물의 균열 검출 시스템 개발)

  • Lee, Ho Beom;Kim, Jong Woo;Jang, Il Young
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.16 no.1
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    • pp.64-77
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    • 2012
  • In this study, the crack detecting system with digital image processing techniques based on the mathematical morphology method was developed to detect cracks in concrete structures. In the developed system, the image combining technique of reconstructing multiple images as an entire single image considering efficient management of analysis results was applied as an additional module. The developed system was verified through a field test with the cracked concrete culvert and the crack width of 0.2 mm was able to be detected in the 40m span. In the image analysis, the difference between calculated crack width and actual crack width were less than 0.08mm. For image combination in the stitching test of pattern images, the stitched image was identical with the original picture of entire subject in the visual perception level.

The Development and Introduction of External Corrosion Direct Assessment Measures for Urban Gas Pipelines (외면부식 직접평가법 개발 및 국내 도입 연구)

  • Ryou, Young-Don;Lee, Jin-Han;Yoon, Yung-Ki;Lim, Ho-Seok
    • Journal of the Korean Institute of Gas
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    • v.18 no.5
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    • pp.12-19
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    • 2014
  • To minimize the risk of corrosion on buried pipeline and to maximize the efficiency of cathodic protection, various indirect inspection techniques have been used for decades. In the United States, 49 CFR has regulated the external corrosion direct assessment for buried pipelines. In Korea, there is no provision for external corrosion direct assessment but there is only, according to the KGS Code, provision that if the survey of the defects of buried pipeline and the leakage test for the pipe were conducted, it is deemed to leakage inspection. We, therefore, have suggested external corrosion direct assessment method appropriate to domestic status through the survey of the regulations and standards of UK and the USA and the investigation of domestic situation on coating damage detection method. The proposed external corrosion direct evaluation method was used as the basis when introducing the precision safety diagnosis regulation for the medium-pressure pipe in Korea.

Modelling land degradation in the mountainous areas

  • Shrestha, D.P.;Zinck, J.A.;Ranst, E. Van
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.817-819
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    • 2003
  • Land degradation is a crucial issue in mountainous areas and is manifested in a variety of processes. For its assessment, application of existing models is not straightforward. In addition, data availability might be a problem. In this paper, a procedure for land degradation assessment is described, which follows a four-step approach: (1) detection, inventory and mapping of land degradation features, (2) assessing the magnitude of soil loss, (3) study of causal factors, and (4) hazard assessment by applying decision trees. This approach is applied to a case study in the Middle Mountain region of Nepal. The study shows that individual mass movement features such as debris slides and slumps can be easily mapped by photo interpretation techniques. Application of soil loss estimation models helps get insight on the magnitude of soil losses. In the study area soil losses are higher in rainfed crops on sloping terraces (highest soil loss is 32 tons/ha/yr) and minimal under dense forest and in irrigated rice fields (less than 1 ton/ha/yr). However there is high frequency of slope failures in the form of slumps in the rice fields. Debris slides are more common on south-facing slopes under rainfed agriculture or in degraded forest. Field evidences and analysis of causal factors for land degradation helps in building decision trees, the use of which for modelling land degradation has the advantage that attributes can be ranked and tested according to their importance. In addition, decision trees are simple to construct, easy to implement and very flexible in adaptations.

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A Study of UGI Series for Improvement of Diagnosis on the Anterior Wall of the Stomach (위 전벽 병변 진단을 위한 UGI series의 실태 및 개선방안에 관한 고찰)

  • Lee, Won-Hong;Son, Soon-Yong;Kang, Hyoung-Wook
    • Journal of radiological science and technology
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    • v.20 no.2
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    • pp.63-67
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    • 1997
  • This paper is to investigate a more detailed method for the diagnosis of anterior wall of the stomach by making a comparative study with several hospitals. It has been true that there have been hospitals, that have not examined anterior wall of the stomach. However, it is very important for us to examine anterior wall of the stomach for an carly detection of gastric carcinoma. The results of th study are as follows : 1. Frequency of occurrence of the early gastric carcinoma for the anterior wall were 50 cases and 34 cases for the posterior wall out of 84 cases. 2. Only a hospitals have examined the anterior wall of stomach. 3. In case of operation, only a hospitals have used two techniques at for same time single and double contrast studies. 4. Only cue hospital used a compression pad and three hospitals hod only filing state images taloen. 5. In general, 1 chest of film was used and the number of exposures rouged from 1 to 2 times. Lesions on the anterior wall of the stomach can be shown by the combination of prone single com-pression and supine double contrast radiographs. Therefore, the conclusion came to the result that the prone single compression and supine double contract technique of the anterior wall are Indispensable methods to the routine check of the stomach.

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Shoreline Changes Interpreted from Multi-Temporal Aerial Photographs and High Resolution Satellite Images. A Case Study in Jinha Beach (다중시기 항공사진과 KOMPSAT-3 영상을 이용한 진하해수욕장 해안선 변화 탐지)

  • Hwang, Chang Su;Choi, Chul Uong;Choi, Ji Sun
    • Korean Journal of Remote Sensing
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    • v.30 no.5
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    • pp.607-616
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    • 2014
  • This research is to observe the shoreline changes in Jinha beach over the 50 years with aerial photographs and satellite images. The shoreline image feature was retrieved from the corrected images using wet and dry techniques and analyzed by DSAS from the statistical point of view. From 1967 to 1992, the mouth of Hoeya River was severely blocked and the northern shoreline off Jinha beach was eroded. The blockade of river mouth seemed to have been eased along with the completion of the dike, but soil continued to be deposited along the high sea away from the river month. Compared to the past, a layer of sediment has been formed off the northern coastline while the southern coastline has eroded. At least in the region subject to this research, the construction of a training dike is to blame. On top of that, a mere combination of dredges and artificial nourishment is not enough to take under control the changing shorelines properly. Thus, it is necessary to devise a more fundamental solution by taking into account reasons behind sediment from the river area that could change the shorelines besides the costal environment.

Characterization of saturation of CR-39 detector at high alpha-particle fluence

  • Ghazaly, M. El;Hassan, Nabil M.
    • Nuclear Engineering and Technology
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    • v.50 no.3
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    • pp.432-438
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    • 2018
  • The occurrence of saturation in the CR-39 detector reduces and limits its detection dynamic range; nevertheless, this range could be extended using spectroscopic techniques and by measuring the net bulk rate of the saturated CR-39 detector surface. CR-39 detectors were irradiated by 1.5 MeV high alpha-particle fluence varying from $0.06{\times}10^8$ to $7.36{\times}10^8\;alphas/cm^2$ from Am-241 source; thereafter, they were etched in a 6.25N NaOH solution at a temperature of $70^{\circ}C$ for different durations. Net bulk etch rate measurement of the 1.5 MeV alpha-irradiated CR-39 detector surface revealed that rate increases with increasing etching time and reaches its maximum value at the end of the alpha-particle range. It is also correlated with the alpha-particle fluence. The measurements of UV-Visible (UV-Vis) absorbance at 500 and 600 nm reveal that the absorbance is linearly correlated with the fluence of alpha particles at the etching times of 2 and 4 hour. For extended etching times of 6, 10, and 14.5 hour, the absorbance is saturated for fluence values of $4.05{\times}10^8$, $5.30{\times}10^8$, and $7.36{\times}10^8\;alphas/cm^2$. These new methods pave the way to extend the dynamic range of polymer-based solid state nuclear track detectors (SSNTDs) in measurement of high fluence of heavy ions as well as in radiation dosimetry.

Concept Development and Review of Current Technical Issues for SFR Steam Generator (소듐냉각 고속로용 증기발생기 기술분석 및 개념개발)

  • Nam, Ho-Yun;Kim, Jong-Bum;Lee, Jae-Han;Park, Chang-Gyu
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.35 no.9
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    • pp.1083-1090
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    • 2011
  • A steam generator poses many difficulties during the development of a sodium-cooled fast reactor because of the sodium-water-reaction problems. Until now, several types of steam generators have been developed, but the specifications of these generators differed in each country. Moreover, even if a country had developed a steam generator, it was not used in the subsequent reactor because the current techniques were not stabilized to select the proper steam generator. As a common development, the Benson steam cycle with few welding locations and high economical efficiency may be adopted. Moreover, the design is dwelled on the convenience of inspection, detection, control, and maintenance for the wear caused by sodiumwater reactions. The specifications of the designed steam generators were reviewed and the current technical problems for steam generators were analyzed. Concepts were proposed to overcome the current technical problems for steam generators.