• Title/Summary/Keyword: 재구성기법

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Attribute-based Dynamic Reconfiguration of USN Sensor Node (속성 기반의 USN 센서 노드 동적 재구성 기법)

  • Jung, Hyun-June;Kim, Ju-Il;Khil, A-Ra;Chong, Ki-Won;Lee, Woo-Jin
    • Proceedings of the Korean Information Science Society Conference
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    • 2008.06d
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    • pp.191-195
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    • 2008
  • 센서 노드 미들웨어는 다양한 센서 응용 소프트웨어와 운영체제 및 네트워크 기능 사이에 존재하며, 유지보수, 설치, 배포, 응용 수행에 필요한 제반 사항을 지원하며, 센서 노드에 탑재되어 센서 네트워크의 프로그램 갱신, 응용 변화에 따른 프로그래밍 조정을 수행한다. 본 논문에서는 센서 노드 미들웨어가 센서 노드의 응용 모듈을 동적으로 재구성하기 위한 방법으로 속성 값 단위의 동적 재구성 기법을 제안한다. 제안하는 기법은 센서 노드의 응용 모듈을 변경해야 할 필요가 있을 경우, 응용 모듈과 관련된 속성의 값을 변경시켜 줌으로써 응용 모듈을 재구성하는 방법이다. 논문에서는 제안하는 동적 재구성의 개념과 동적 재구성을 위한 프로세스 및 알고리즘을 설명한다. 제시하는 기법은 각처에 설치되어 동작중인 센서 노드들을 무선 통신을 이용하여 재구성함으로써 직접 센서 노드들을 떼어내거나 동작을 중단시키지 않고도 재구성함으로써 운영의 편의를 도모할 수 있는 효과가 있다. 또한 속성 값을 통한 동적 재구성방법을 통하여 용량이 큰 이미지 파일 전송으로 인한 통신 오버헤드를 줄이고 그로인해 배터리 소모를 줄 일수 있다.

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Evaluation of Image Quality and Radiation Dose for Filtered Back-Projection and Iterative Reconstruction Algorithm in Abdominal Computed Tomography Protocol (복부 CT 프로토콜에서 필터 보정 역투영법과 반복적 재구성기법에 따른 화질 및 선량에 관한 연구)

  • Oh, Jeong-Min;Seo, Hyeon-Ji;Kim, Yung-Kyoon;Han, Dong-Kyoon
    • Journal of the Korean Society of Radiology
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    • v.15 no.7
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    • pp.1065-1072
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    • 2021
  • In Computed Tomography, abdominal examination showed the highest proportion of use, and effort of reducing the radiation dose is required. Recently introduced Iterative Reconstruction(IR) is repetitive reconstruction technique of Computed Tomography. SIEMENS' IR, ADMIRE and GE's IR, ASIR-V, were used in this examination. Noise, % Contrast, and High contrast resolution were measured by using ACR phantom for image quality evaluation. In addition, CTDIvol and DLP displayed in the CT device were used for dose evaluation. When FBP and IR were compared, stage 2 to stage 5 of ADMIRE and 10, 30, 50, 70, and 90% of ASIR-V were applied, noise could be reduced from a minimum of 0.46 to a maximum of 2.38 in ADMIRE compared to FBP, and noise from a minimum of 0.51 to a maximum of 2.5 in ASIR-V compared to FBP. Also, % Contrast and High contrast resolution of FBP and IR were no statistical difference. When IR was used for abdominal CT examination, the radiation dose of ADMIRE is reduced by 25.39% compared to the radiation dose of FBP. Also, the radiation dose of ASIR-V is reduced by 16.61% compared to the radiation dose of FBP. In conclusion, it is believed that if IR is applied during abdominal CT examination, the radiation dose can be reduced without deteriorating the image quality.

Reconstruction System of Road Environment using Image-based Modeling (이미지 기반 모델링을 이용한 도로환경 재구성 시스템)

  • Lee, Kye-Young;Lee, Yong-Jae;Shin, Yeong Gil
    • Journal of the Korea Computer Graphics Society
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    • v.3 no.1
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    • pp.17-22
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    • 1997
  • This paper presents a new modeling technique to reconstruct road environments. The reconstruction algorithm for road environments consists of three parts - reconstructing 3D models of architectures in road environments, editing and creating road models, and modeling auxiliary objects. Different modeling technique is applied to each of these three parts according to properties objects to be modeled contain. In this reconstruction system, modified Photogrammetric Modeling techique is used, of which the user interface is more convenient, and in which constraints of road environments are considered. These improvements make this road environment reconstruction system much simpler and easier to use compared with Photogrammetric Modeling technique[1, 2].

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Dynamic Kernel Reconfiguration Mechanism based on Trap (트랩 기반의 동적 커널 재구성 기법)

  • Son, Jae-Woong;Kim, Young-Pill;Yoo, Hyuck
    • Annual Conference of KIPS
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    • 2005.05a
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    • pp.1709-1712
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    • 2005
  • 최근 사용자의 요구가 다양해지는 반면, 기존 운영체제는 정적인 구조를 갖기 때문에 이러한 요구를 효율적으로 반영하기 어렵다. 따라서 운영체제를 동적으로 재구성하여 사용자의 요구를 만족시키는 매커니즘에 관한 연구들이 진행되어 왔다. 그러나 기존의 커널을 재구성하는 기법들은 하드웨어 의존적인 문제점을 가지고 있다. 본 논문에서는 기존 연구들의 문제점을 해결할 수 있는 트랩 기반의 커널 재구성 기법을 제안하고 리눅스 커널에 구현하였다.

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Dynamic Reconfigurable Mechanism using Asynchronous Replacement of Component (컴포넌트의 비동기적 교체를 이용한 동적 재구성 기법)

  • Song, In-Jun;Kim, Young-Pil;Kim, Kyeong-Yun;Yoo, Hyuck
    • Proceedings of the Korean Information Science Society Conference
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    • 2004.04a
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    • pp.148-150
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    • 2004
  • 최근 내장형 시스템의 보급과 발전으로 휴대용 기기에서 다양한 애플리케이션들을 이용하고 있다. 특히. 핸드폰과 스마트폰과 같은 정보 통신 기기들은 과거의 전화 기능 외에도 개인 정보 관리 및 게임 등 다양한 기능을 수행한다. 또한 차세대 무선 통신 기술로써 SDR(Software Defined Radio)등의 연구가 이루어지고 있다. 이렇게 소형의 휴대 기기에서 다양한 기능과 서비스를 제공하기 위해서는 시스템의 구조가 동적으로 재구성되어야 할 필요성이 증대되고 있다. SDR 시스템의 경우, 하나의 장치에서 두 개 이상의 신호 처리(Signal Processing) 기법이 소프트웨어적으로 제공되어야 한다. 이러한 유연성(Flexibility) 및 재구성(Reconfigurability)을 요건들을 만족시키는 시스템을 위해서는 운영체제 단계에서 동적인 재구성 기법을 제공해주어야 한다. 본 논문에서는 컴포넌트의 비동기적(Asynchronous) 교체를 이용하여 기존의 동적 재구성 기법의 지연 시간을 줄이는 방법을 설명하며 실험을 통해 그것을 증명하도록 한다.

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A Dynamic Reconfiguration Method using Application-level Checkpointing in a Grid Computing Environment with Cactus and Globus (Cactus와 Globus에 기반한 그리드 컴퓨팅 환경에서의 응용프로그램 수준의 체크포인팅을 사용한 동적 재구성 기법)

  • Kim Young Gyun;Oh Gil-ho;Cho Kum Won;Na Jeoung-Su
    • Journal of KIISE:Computing Practices and Letters
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    • v.11 no.6
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    • pp.465-476
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    • 2005
  • In this paper, we propose a new dynamic reconfiguration method using application-level checkpointing in a grid computing environment with Cactus and Globus. The existing dynamic reconfiguration methods have been dependent on a specific hardware and operating system. But the proposed method performs a dynamic reconfiguration without supporting specific hardwares and operating systems and, an application is programmed without considering a dynamic reconfiguration. In the proposed method, the job starts with an initial configuration of Computing resources and the job restarts including new resources dynamically found at run-time. The proposed method determines whether to include the newly found idle sites by considering processor performance and available memory of the sites. Our method writes the intermediate results of the job on the disks using system-independent application-level checkpointing for real-time visualization during the job runs. After reconfiguring idle sites and idle processors newly found, the job resumes using checkpointing files. The proposed dynamic reconfiguration method is proved to be valid by decreasing total execution time In K*Grid.

Evaluation on usefulness of three dimensional reconstructive computed tomography images after pedicle screws fixation (척추경 나사못 고정술 시행 후 3차원 재구성CT영상의 유용성 평가)

  • Kim, Hyeon-Ju;Jang, Hyun-Chul;Cho, Jae-Hwan
    • Journal of Digital Contents Society
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    • v.11 no.4
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    • pp.553-559
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    • 2010
  • By applying the various reformation techniques by using a circle raw data of after computed tomography image in the patient enforcing the spine screw fixation, this research tried to look into the various information including the exact location of the position of the screw spike and accuracy of an operation. In a clinical, by applying the or multi planar reformatting(MPR), that is the re-composition technique used mainly, maximum intensity projection (MIP), and volume rendering technique(VRT) and transformation removal from a register modifying VRT, video data were compared and were analyzed by the quantitative method and qualitative method. It is judged as the transformation volume rendering technique of the re-composition technique which is most useful in minimizing the artifact shadow by the exact location of the position of a screw and metal among the analysis and evaluation result computed tomography image reformation technique of the reformation image after the spine screw fixation.

A Study on the Usefulness of Deep Learning Image Reconstruction with Radiation Dose Variation in MDCT (MDCT에서 선량 변화에 따른 딥러닝 재구성 기법의 유용성 연구)

  • Ga-Hyun, Kim;Ji-Soo, Kim;Chan-Deul, Kim;Joon-Pyo, Lee;Joo-Wan, Hong;Dong-Kyoon, Han
    • Journal of the Korean Society of Radiology
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    • v.17 no.1
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    • pp.37-46
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    • 2023
  • This study aims to evaluate the usefulness of Deep Learning Image Reconstruction (TrueFidelity, TF), the image quality of existing Filtered Back Projection (FBP) and Adaptive Statistical Iterative Reconstruction-Veo (ASIR-V) were compared. Noise, CNR, and SSIM were measured by obtaining images with doses fixed at 17.29 mGy and altered to 10.37 mGy, 12.10 mGy, 13.83 mGy, and 15.56 mGy in reconstruction techniques of FBP, ASIR-V 50%, and TF-H. TF-H has superior image quality compared to FBP and ASIR-V when the reconstruction technique change is given at 17.29 mGy. When dose changes were made, Noise, CNR, and SSIM were significantly different when comparing 10.37 mGy TF-H and FBP (p<0.05), and no significant difference when comparing 10.37 mGy TF-H and ASIR-V 50% (p>0.05). TF-H has a dose-reduction effect of 30%, as the highest dose of 15.56 mGy ASIR-V has the same image quality as the lowest dose of 10.37 mGy TF-H. Thus, Deep Learning Reconstruction techniques (TF) were able to reduce dose compared to Iterative Reconstruction techniques (ASIR-V) and Filtered Back Projection (FBP). Therefore, it is considered to reduce the exposure dose of patients.

A Reconfiguration Technique of Logical Topology in a Ship Backbone Network (선박 백본 네트워크의 논리 토폴로지 재구성 기법)

  • Tak, Sung-Woo
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.16 no.5
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    • pp.922-931
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    • 2012
  • This paper studies a series of logical topology reconfiguration processes corresponding to a series of traffic demand changes in a ship backbone network. The proposed reconfiguration technique is to minimize costly changes of traffic forwarding paths and minimize the average hop distance of traffic forwarding paths in terms of ship backbone network performance simultaneously. Performance evaluation is conducted to illustrate the efficiency of the proposed reconfiguration technique. It shows that the proposed reconfiguration technique yields efficient performance in the entire series of reconfiguration processes.

Quantitative analysis of three dimensional volumetric images in Chest CT (흉부 CT 검사에서 3차원 체적 영상의 정량적 분석)

  • Jang, Hyun-Cheol;Cho, Jae-Hwan;Park, Cheol-Soo
    • Journal of the Korean Society of Radiology
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    • v.5 no.5
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    • pp.255-260
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    • 2011
  • We wanted to evaluate the usefulness of three-dimensional reconstructive images using computed tomography for rib fracture patients. The reconstruction used in clinical multi planar reformation(MPR), volume rendering technique(VRT), and image data using quantitative methods and qualitative methods were compared. Much more, the artifact shadow was minimized to reconstruct with 3D volumetric image by using an law data in the analysis of the reconstructive image and chest CT scan of the evaluation result fractures of the thoracic patient. And we could know that the fractures of the thoracic determination and three dimension volume image reconstruction time were reduced.