• 제목/요약/키워드: and Pre-Processing

검색결과 1,916건 처리시간 0.03초

Contrast Enhancement for Segmentation of Hippocampus on Brain MR Images

  • Sengee, Nyamlkhagva;Sengee, Altansukh;Adiya, Enkhbolor;Choi, Heung-Kook
    • 한국멀티미디어학회논문지
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    • 제15권12호
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    • pp.1409-1416
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    • 2012
  • An image segmentation result depends on pre-processing steps such as contrast enhancement, edge detection, and smooth filtering etc. Especially medical images are low contrast and contain some noises. Therefore, the contrast enhancement and noise removal techniques are required in the pre-processing. In this study, we present an extension by a novel histogram equalization in which both local and global contrast is enhanced using neighborhood metrics. When checking neighborhood information, filters can simultaneously improve image quality. Most important is that original image information can be used for both global brightness preserving and local contrast enhancement, and image quality improvement filtering. Our experiments confirmed that the proposed method is more effective than other similar techniques reported previously.

유한요소 구조해석을 위한 객체지향 전처리 프로그램에 관한 연구 (A Study on Object-Oriented Preprocessing Program for Finite Element Structural Analysis)

  • 신영식;서진국;송준엽;우광성
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1994년도 봄 학술발표회 논문집
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    • pp.25-32
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    • 1994
  • The pre-processor for finite to element structural analysis considering the user-friendly device is developed by using GUI. This can be used on WINDOWS' environment which is realized the multi-tasking and the concurrency by object-oriented paradigm. Data input can be done easily through menu, dialog box, automatic stepwise input and concurrent representation with the structural geometry on multiple windows. It in designed to control integratedly the pre-processing, execution and the post-processing of the finite element structural analysis program on multiple windows, and input data can be seen with result outputs at the same time. In addition, the object-oriented programming environment makes convenient revision and addition of the program components for expanding the scope of analysis and making better user environment.

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Consolidation 방법에 의해 제작된 유리섬유강화 복합재료의 결정성과 기계적성질에 관한 연구 (Crystallinity and Mechanical Properties of Glass Fiber Reinforced Thermoplastic Composites by Rapid Press Consolidation Technique)

  • 신익재;김동영;이동주
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 춘계학술대회논문집A
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    • pp.91-96
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    • 2000
  • Glass fiber reinforced thermoplastic composites were manufactured by Rapid Press Consolidation Technique(RPCT) as functions of temperature, pressure and time in pre-heating, consolidation and solidification sections during the manufacturing processing. It was found that the material property is greatly affected by pre-heating temperature under vacuum, mold temperature and molding pressure. Among them, the temperature In the mold was the most critical factor in determining the mechanical properties and the molded conditions of specimen. The crystallinity of PET matrix was also investigated by differential scanning calorimetry(DSC) measurements for various processing conditions. The level of crystallinity($X_c$) depended strongly on the mold temperature, cooling rate and the type of composite. The difference in $X_c$ is believed to be one of important factors in characterizing the mechanical properties.

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효율적인 휴리스틱 계산 처리를 위한 가중치 기반의 선수행 A* 알고리즘 (A Weighted based Pre-Perform A* Algorithm for Efficient Heuristics Computation Processing)

  • 오민석;박성준
    • 한국게임학회 논문지
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    • 제13권6호
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    • pp.43-52
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    • 2013
  • 경로 탐색은 인공지능의 매우 중요한 요소 중의 하나이며, 여러 분야에서 두루 쓰이는 과정이다. 경로 탐색은 매우 많은 연산이 필요하기 때문에 성능에 매우 중대한 영향을 미친다. 이를 해결하기 위해서 연산량을 줄이는 방식의 연구가 많이 진행되었고, 대표적으로 A* 알고리즘이 있으나 불필요한 연산이 있어 효율성이 떨어진다. 본 논문에서는 A* 알고리즘 중 연산 비용이 높은 노드 탐색 수 등 연산량을 줄이기 위해서 가중치 기반의 선수행 A* 알고리즘을 새롭게 제안한다. 제안한 알고리즘의 효율성을 측정하기 위해 시뮬레이션을 구현하였으며, 실험 결과 가중치를 이용하는 방법이 일반적인 방법보다 약 1~2배 높은 효율을 보였다.

Bending Machine의 서보제어에 의한 고정도 굽힘가공에 관한 연구 (A Study on High Accuracy Bending Work using Servo Control of Bending Machine)

  • 송충현;김성식;김경석
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2001년도 추계학술대회(한국공작기계학회)
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    • pp.85-90
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    • 2001
  • Recent general Press brake has many problems in cutting high accurate products in the progress of industry. Previous hand-operated press brake needs many pre-processing works to adjust bending ang1e and marking-off works to calculate bending length. Also, the hand-operating work makes many geometric errors and has difficulty for variety-mass production. To solve these problems, this paper proposes Computer Numerical Control (CNC) general press brake and development of servo-control system based on database for reduction of geometric errors and pre-processing work time and high accuracy bending work.

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DESIGN OF COMMON TEST HARNESS SYSTEM FOR SATELLITE GROUND SEGMENT DEVELOPMENT

  • Seo, Seok-Bae;Kim, Su-Jin;Koo, In-Hoi;Ahn, Sang-Il
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.544-547
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    • 2007
  • Because data processing systems in recent years are more complicated, main function of the data processing is divided as several sub-functions which are implemented and verified in each subsystem of the data processing system. For the verification of data processing system, many interface tests among subsystems are required and also a lot of simulation systems are demanded. This paper proposes CTHS (Common Test Harness System) for satellite ground segment development which has all of functions for interface test of the data processing system in one PC. Main functions of the CTHS software are data interface, system log generation, and system information display. For the interface test of the data processing system, all of actions of the CTHS are executed by a pre-defined operation scenario which is written by purpose of the data processing system test.

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Clinical Application of Automatic EEG Interpretation: Automatic Detection of Artifacts and Vigilance Level

  • Nakamura, Masatoshi;Sugi, Takenao;Shibasaki, Hiroshi;Ikeda, Akio
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1994년도 Proceedings of the Korea Automatic Control Conference, 9th (KACC) ; Taejeon, Korea; 17-20 Oct. 1994
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    • pp.572-577
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    • 1994
  • The automatic detection of artifacts and vigilance level as for pre-processing of the automatic EEG interpretation are discussed. The equations for detecting artifacts and vigilance level were determined such that they would conform to the procedures that an EEGer (one of the authors, H.S.) usually adopts for visual inspection of the actual EEG record. The automatic EEG interpretation was found to be improved by the newly developed pre-processing method even will artifact contamination or in drowsy condition of the subjects.

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Bending Machine의 서보제어에 관한 연구 (A Study on the Servo Control of Bending Machine)

  • 송충현;김성식;김경석
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 1997년도 추계학술대회 논문집
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    • pp.410-413
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    • 1997
  • Recent general press brake has many problems in cutting high accurate products in the progress of industry. Previous hand-operated press brake needs many pre-processing works to adjust bending angle and marking-off works to calculate bending length. Also, The hand-operating work makes many geometric errors and has difficulty for variety-mass production. To solve these problems, this paper proposes Computer Numerical Control (CNC) general press brake and development of servo-control system based on database for reduction of geometric errors and pre-processing work time.

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Detection of Subsurface Defects in Metal Materials Using Infrared Thermography; Image Processing and Finite Element Modeling

  • Ranjit, Shrestha;Kim, Won Tae
    • 비파괴검사학회지
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    • 제34권2호
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    • pp.128-134
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    • 2014
  • Infrared thermography is an emerging approach to non-contact, non-intrusive, and non-destructive inspection of various solid materials such as metals, composites, and semiconductors for industrial and research interests. In this study, data processing was applied to infrared thermography measurements to detect defects in metals that were widely used in industrial fields. When analyzing experimental data from infrared thermographic testing, raw images were often not appropriate. Thus, various data analysis methods were used at the pre-processing and processing levels in data processing programs for quantitative analysis of defect detection and characterization; these increased the infrared non-destructive testing capabilities since subtle defects signature became apparent. A 3D finite element simulation was performed to verify and analyze the data obtained from both the experiment and the image processing techniques.

A CPU-GPU Hybrid System of Environment Perception and 3D Terrain Reconstruction for Unmanned Ground Vehicle

  • Song, Wei;Zou, Shuanghui;Tian, Yifei;Sun, Su;Fong, Simon;Cho, Kyungeun;Qiu, Lvyang
    • Journal of Information Processing Systems
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    • 제14권6호
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    • pp.1445-1456
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    • 2018
  • Environment perception and three-dimensional (3D) reconstruction tasks are used to provide unmanned ground vehicle (UGV) with driving awareness interfaces. The speed of obstacle segmentation and surrounding terrain reconstruction crucially influences decision making in UGVs. To increase the processing speed of environment information analysis, we develop a CPU-GPU hybrid system of automatic environment perception and 3D terrain reconstruction based on the integration of multiple sensors. The system consists of three functional modules, namely, multi-sensor data collection and pre-processing, environment perception, and 3D reconstruction. To integrate individual datasets collected from different sensors, the pre-processing function registers the sensed LiDAR (light detection and ranging) point clouds, video sequences, and motion information into a global terrain model after filtering redundant and noise data according to the redundancy removal principle. In the environment perception module, the registered discrete points are clustered into ground surface and individual objects by using a ground segmentation method and a connected component labeling algorithm. The estimated ground surface and non-ground objects indicate the terrain to be traversed and obstacles in the environment, thus creating driving awareness. The 3D reconstruction module calibrates the projection matrix between the mounted LiDAR and cameras to map the local point clouds onto the captured video images. Texture meshes and color particle models are used to reconstruct the ground surface and objects of the 3D terrain model, respectively. To accelerate the proposed system, we apply the GPU parallel computation method to implement the applied computer graphics and image processing algorithms in parallel.