• Title/Summary/Keyword: Hard real-time

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Study on the Real Time Medical Image Processing (실시간 의학 영상 처리에 관한 연구)

  • 유선국;이건기
    • Journal of Biomedical Engineering Research
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    • v.8 no.2
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    • pp.118-122
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    • 1987
  • The medical image processing system is intended for a diverse set of users in the medical Imaging Parts. This system consists of a 640 Kbyte IBM-PC/AT with 30 Mbyte hard disk, special purpose image processor with video input devices and display monitor. Image may be recorded and processed in real time at sampling rate up to 10 MHz. This system provides a wide range of image enhancement processing facilities via a menu-driven software packages. These facilities include point by point processing, image averaging, convolution filter and subtraction.

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High-speed Image Processing for Blurred Image for an Object Detection (블러가 심한 물체 검출을 위한 고속 MMX 영상처리)

  • Lee, Jae-Hyeok
    • Proceedings of the KIEE Conference
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    • 2005.10b
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    • pp.177-179
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    • 2005
  • This paper suggests a high-speed blurred blob image inspection algorithm. When we inspect some products using high-resolution camera, the detected blob images usually have severe blur. And the blur makes it hard to detect an object. There are many blur-processing algorithms, but most of them have no real-time property for high-speed applications at all. In this paper, an MMX technology based algorithm is suggested. The suggested algorithm was found to be effective to detect the blurred blob images via many simulations and long time real-plant experiments.

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Development of a Heuristic Algorithm Based on Simulated Annealing for Time-Resource Tradeoffs in Project Scheduling Problems (시간-자원 트레이드오프 프로젝트 스케줄링 문제 해결을 위한 시뮬레이티드 어닐링 기반 휴리스틱 알고리즘 개발)

  • Kim, Geon-A;Seo, Yoon-Ho
    • The Journal of Information Systems
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    • v.28 no.4
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    • pp.175-197
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    • 2019
  • Purpose This study develops a heuristic algorithm to solve the time-resource tradeoffs in project scheduling problems with a real basis. Design/methodology/approach Resource constrained project scheduling problem with time-resource tradeoff is well-known as one of the NP-hard problems. Previous researchers have proposed heuristic that minimize Makespan of project scheduling by deriving optimal combinations from finite combinations of time and resource. We studied to solve project scheduling problems by deriving optimal values from infinite combinations. Findings We developed heuristic algorithm named Push Algorithm that derives optimal combinations from infinite combinations of time and resources. Developed heuristic algorithm based on simulated annealing shows better improved results than genetic algorithm and further research suggestion was discussed as a project scheduling problem with multiple resources of real numbers.

Dynamic Voltage Scaling Algorithms for Hard Real-Time Systems Using Efficient Slack Time Analysis (효율적인 슬랙 분석 방법에 기반한 경성 실시간 시스템에서의 동적 전압 조절 방안)

  • 김운석;김지홍;민상렬
    • Journal of KIISE:Computer Systems and Theory
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    • v.30 no.12
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    • pp.736-748
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    • 2003
  • Dynamic voltage scaling(DVS), which adjusts the clock speed and supply voltage dynamically, is an effective technique in reducing the energy consumption of embedded real-time systems. The energy efficiency of a DVS algorithm largely depends on the performance of the slack estimation method used in it. In this paper, we propose novel DVS algorithms for periodic hard real-time tasks based on an improved slack estimation algorithm. Unlike the existing techniques, the proposed method can be applied to most priority-driven scheduling policies. Especially, we apply the proposed slack estimation method to EDF and RM scheduling policies. The experimental results show that the DVS algorithms using the proposed slack estimation method reduce the energy consumption by 20∼40 % over the existing DVS algorithms.

Rate-Monotonic Scheduler with Extended Schedulability Inspection for Hard Real-Time Tesk (경성 실시간 태스크를 위한 확장된 스케줄 가능성 검사를 갖는 비율단조 스케줄러)

  • 신동헌;조수현;김영학;김태형
    • The Journal of the Korea Contents Association
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    • v.4 no.2
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    • pp.50-60
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    • 2004
  • Recently, most of the embedded system is required not only many functions but also real-time characteristics in purpose. In the hard real-time system, especially, strict deadline of periodic task can affect the performance of the system. In this paper, we design and implement the scheduler based on RM(Rate-Monotonic) rule. This scheduler makes feasible patterns based on EDF(Earliest deadline first) rule with extended schedulability inspection before execution, for periodic task-set that has high CPU utilization and then, execute periodic task-set depended on feasible patterns. The feasible pattern formed into EDF rule is capable of the efficiency of CPU up to 100 percentage and by the referenced execution of the feasible pattern is possible of removing the red-time scheduling overhead that is the defect of the order of dynamic assignment rule.

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Practical and Verifiable C++ Dynamic Cast for Hard Real-Time Systems

  • Dechev, Damian;Mahapatra, Rabi;Stroustrup, Bjarne
    • Journal of Computing Science and Engineering
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    • v.2 no.4
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    • pp.375-393
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    • 2008
  • The dynamic cast operation allows flexibility in the design and use of data management facilities in object-oriented programs. Dynamic cast has an important role in the implementation of the Data Management Services (DMS) of the Mission Data System Project (MDS), the Jet Propulsion Laboratory's experimental work for providing a state-based and goal-oriented unified architecture for testing and development of mission software. DMS is responsible for the storage and transport of control and scientific data in a remote autonomous spacecraft. Like similar operators in other languages, the C++ dynamic cast operator does not provide the timing guarantees needed for hard real-time embedded systems. In a recent study, Gibbs and Stroustrup (G&S) devised a dynamic cast implementation strategy that guarantees fast constant-time performance. This paper presents the definition and application of a cosimulation framework to formally verify and evaluate the G&S fast dynamic casting scheme and its applicability in the Mission Data System DMS application. We describe the systematic process of model-based simulation and analysis that has led to performance improvement of the G&S algorithm's heuristics by about a factor of 2. In this work we introduce and apply a library for extracting semantic information from C++ source code that helps us deliver a practical and verifiable implementation of the fast dynamic casting algorithm.

Intelligent quality estimation system using primary circuit variables of RSW (저항점용접 1차 공정변수를 이용한 지능형 용접품질 판단 시스템)

  • 조용준;이세헌;신현일;배경민;권태용
    • Proceedings of the KWS Conference
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    • 1999.10a
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    • pp.142-145
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    • 1999
  • The dynamic resistance monitoring is one of the important issues in that in-process and real time quality assurance of resistance spot weld is needed to increase the product reliability. Secondary dynamic resistance patterns, as a real manner, are hard to adapt those factors in real time and in-plant system. In the present study, a new dynamic resistance detecting method is presented as a practical manner of weld quality assurance at the primary circuit. By the correlation analysis, it is found that the primary dynamic resistance patterns are basically similar to those of the secondary. Various dynamic resistance indices are characterized with the primary curve. And quality of the weld, like the tensile shear strength, is estimated using adaptive neuro-fuzzy estimation system which is consisted of the Sugeno fuzzy algorithm. Through the fuzzy clustering and parameter optimization, real time weld quality assurance system with less efforts is proposed.

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Photorealistic Real-Time Dense 3D Mesh Mapping for AUV (자율 수중 로봇을 위한 사실적인 실시간 고밀도 3차원 Mesh 지도 작성)

  • Jungwoo Lee;Younggun Cho
    • The Journal of Korea Robotics Society
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    • v.19 no.2
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    • pp.188-195
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    • 2024
  • This paper proposes a photorealistic real-time dense 3D mapping system that utilizes a neural network-based image enhancement method and mesh-based map representation. Due to the characteristics of the underwater environment, where problems such as hazing and low contrast occur, it is hard to apply conventional simultaneous localization and mapping (SLAM) methods. At the same time, the behavior of Autonomous Underwater Vehicle (AUV) is computationally constrained. In this paper, we utilize a neural network-based image enhancement method to improve pose estimation and mapping quality and apply a sliding window-based mesh expansion method to enable lightweight, fast, and photorealistic mapping. To validate our results, we utilize real-world and indoor synthetic datasets. We performed qualitative validation with the real-world dataset and quantitative validation by modeling images from the indoor synthetic dataset as underwater scenes.

Energy Saving Potentials of Ventilation Controls Based on Real-time Vehicle Detection in Underground Parking Facilities

  • Cho, Hong-Jae;Park, Joon-Young;Jeong, Jae-Weon
    • International Journal of High-Rise Buildings
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    • v.2 no.4
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    • pp.331-340
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    • 2013
  • The main topic of this paper is to show a possibility of indoor air quality enhancement and the fan energy savings in underground parking facilities by applying the demand-controlled ventilation (DCV) strategy based on the real-time variation of the traffic load. The established ventilation rate is estimated by considering the passing distance, CO emission rate, idling time of a vehicle, and the floor area of the parking facility. However, they are hard to be integrated into the real-time DCV control. As a solution to this problem, the minimum ventilation rate per a single vehicle is derived in this research based on the actual ventilation data acquired from several existing underground parking facilities. And then its applicability to the DCV based on the real-time variation of the traffic load is verified by simulating the real-time carbon monoxide concentration variation. The energy saving potentials of the proposed DCV strategy is also checked by comparing it with those for the current underground parking facility ventilation systems found in the open literature.

Evaluation of the Performance and Reliability of a Real-time Power System Described by a DES Model using Fuzzy-Random Variables (퍼지-랜덤 변수를 이용한 DES 모델링을 통한 실시간 전력 시스템의 성능 및 신뢰도 평가)

  • Min, Byeong-Jo;Lee, Seok-Ju;Kim, Hak-Bae
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.49 no.7
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    • pp.363-369
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    • 2000
  • To flexibly evaluate performance and reliability of an electric power system in the aspect of the real-time system which is intrinsically characterized by stringent timing constraints fails catastrophically if its control input is not updated by its digital controller computer within a certain time limit called the hard deadline, we propose fuzzy-random variables and build a discrete event model embedded with fuzzy-random variables. Also, we adapt fuzzy-variables to a path-space approach, which derives the upper and lower bounds of reliability by using a semi-Markov model that explicitly contains the deadline information. Consequently, we propose certain formulas of state automata properly transformed by fuzzy-random variables, and present numerical examples applying the formulas as well.

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