• Title/Summary/Keyword: real-time mechanism

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Design md Implementation for the Remote Real Time Process Monitoring and Control System based on the JMF (JMF 기반의 실시간 원격 공정 감시 및 제어 시스템 설계 및 구현)

  • Kim, Sam-Ryong;Lim, In-Taek;Lee, Jeong-Bae
    • The KIPS Transactions:PartD
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    • v.11D no.2
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    • pp.453-460
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    • 2004
  • In this thesis, remote conveyor control and monitoring system is designed and Implemented for shoes production process based on Lego prototyping mechanism by using the I/O interface control board for the ISA Interface control board. A conveyor server for real time profess control is implemented based on RTLinux(Real-Time Linux) so that users deride priority of work. And device driver is implemented bated on the RTLinux. Through this system, real-time Client/server monitoring environments Is implemented and tested. And the JMF(Java Media Framework) based monitoring system was implemented and the total processing status war monitored.

A Comparison Study of Real-Time Solution to All- Attitude Angles of an Aircraft

  • Shin Sung-Sik;Lee Jung-Hoon;Yoon Sug-Joon
    • Journal of Mechanical Science and Technology
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    • v.20 no.3
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    • pp.376-381
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    • 2006
  • In this paper, the quaternion, the dual Euler, and the direction cosine methods are numerically compared using a non-aerodynamic 6 degree-of-freedom rigid model at all-attitude angles of an aircraft. The dual Euler method turns out to be superior to the others in the applications because it shows better numerical accuracy, stability, and robustness in integration step sizes. The dual Euler method is affordably less efficient than the quaternion method in terms of computational cost. Numerical accuracy and stability, which allow larger integration step sizes, are more critical in modern real-time applications than computational efficiency because of today's increased computational power. If the quaternion method is required because of constraints in computation time, then a suppression mechanism should be provided for algebraic constraint errors which will eventually add computational burden.

An Implementation of Priority Model of Real-Time CORBA (실시간 CORBA의 우선순위 모델 구현)

  • Park, Sun-Rei;Chung, Sun-Tae
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.38 no.4
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    • pp.59-71
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    • 2001
  • The Current CORBA shows some limitations for its successful deployment in real time system applications. Recently, OMG adopted Real-Time CORBA specification, which is defined as an extension to CORBA. The goal of the Real-Time CORBA is to provide a standard for CORBA ORB implementations that support 'end to end predictability'. In order to support 'end-to-end predictability', Real Time CORBA specifies many components such as priority model, communication protocol configuration, thread management, and etc. Among them, 'priority model' is the most important mechanism for avoiding or bounding priority inversion in CORBA invocations. In this paper, we present our efforts on a design ,and implementation of the Priority Model in Real-Time CORBA specification. The implementation is done as an extension of omniORB2(v.3.0.0), a popular open source non real time ORB. Experiment results demonstrate that our priority model implementation shows better performance and predictability than the non real-time ORB.

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Joint Space Trajectory Planning on RTOS (실시간 운영체제에서 관절 공간 궤적 생성)

  • Yang, Gil-Jin;Choi, Byoung-Wook
    • Journal of the Korean Institute of Intelligent Systems
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    • v.24 no.1
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    • pp.52-57
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    • 2014
  • This paper presents an implementation of a smooth path planning method considering physical limits on a real time operating system for a two-wheel mobile robot. A Bezier curve is utilized to make a smooth path considering a robot's position and direction angle through the defined path. A convolution operator is used to generate the center velocity trajectory to travel the distance of the planned path while satisfying the physical limits. The joint space velocity is computed to drive the two-wheel mobile robot from the center velocity. Trajectory planning, velocity command according to the planned trajectory, and monitoring of encoder data are implemented with a multi-tasking system. And the synchronization of tasks is performed with a real-time mechanism of Event Flag. A real time system with multi-tasks is implemented and the result is compared with a non-real-time system in terms of path tracking to the designed path. The result shows the usefulness of a real-time multi-tasking system to the control system which requires real-time features.

Control Variables of Remote Joint Analysis Realization on the M2M Case

  • Lim, Sung-Ryel;Choi, Bo-Yun;Lee, Hong-Chul
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.6 no.1
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    • pp.98-115
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    • 2012
  • New trend called ubiquitous leads the recent business by standardization and integration. It should be the main issue how to guarantee the integration and accountability on each business, especially in mission critical system which is mainly supported by M2M (Machine to Machine) control mechanism. This study is from the analysis of digital forensics case study that is from the M2M Sensing Control Mechanism problem of the "Imjin River" case in 2009, where a group of family is swept away to death by water due to M2M control error. The ubiquitous surroundings bring the changes in the field of criminal investigation to real time controls such as M2M systems. The needs of digital forensics on M2M control are increasing on every crime scene but we suffer from the lack of control metrics to get this done efficiently. The court asks for more accurately analyzed results accounting high quality product development design. Investigators in the crime scene need real-time analysis against the crime caused by poor quality of mission critical systems. It seems to be every need of Real-Time-Enterprise, so called ubiquitous society on the case. We try to find the efficiency and productivity in discovering non-functional design defects in M2M convergence products focusing on three metrics in study model with quick implementation. Digital forensics system in present status depends on know-how of each investigator and is hard to expect professional analysis on every field. This study set up a hypothesis "Co-working of professional investigators on each field will qualify Performance and Integrity" especially in mission critical system such as M2M and suggests "Online co-work analysis model" to efficiently detect and prevent mission critical errors in advance. At the conclusion, this study proved the statistical research that was surveyed by digital forensics specialists around M2M crime scene cases with quick implementation of dash board.

A Distributed Precedence Queue Mechanism to Assign Efficient Bandwidth in CAN Networks (CAN 네트워크상의 효율적인 대역 할당을 위한 분산 선행대기 열 기법)

  • 최호식;이장명
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.11
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    • pp.1058-1064
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    • 2004
  • This paper presents a distributed precedence queue mechanism to resolve unexpected transmission delay of a lower priority transaction in a CAN based system, which keeps a fixed priority in data transaction. The mechanism is implemented in the upper sub-layer of the data link layer(DLL), which is fully compatible with the original medium access control layer protocol of CAN. Thus the mechanism can be implemented dynamically while the data transactions are going on without any hardware modification. The CAN protocol was originally developed to be used in the automotive industry, and it was recently applied for a broader class of automated factories. Even though CAN is able to satisfy most of real-time requirements found in automated environments, it is not to enforce either a fair subdivision of the network bandwidth among the stations or a satisfactory distribution of the access delays in message transmission. The proposed solution provides a superset of the CAN logical link layer control, which can coexist with the older CAN applications. Through the real experiments, effectiveness of the proposed mechanism is verified.

A Dynamic Precedence Queue Mechanism to Improve Transmission Efficiency in CAN Networks

  • Yun, Jae-Mu;Choi, Ho-Seek;Lee, Jang-Myung
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.761-766
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    • 2005
  • This paper presents a dynamic precedence queue mechanism to resolve unexpected transmission delay of a lower priority transaction in a CAN based system which keeps a fixed priority in data transactions. The mechanism is implemented in the upper sub-layer of the data link layer (DLL), which is fully compatible with the original medium access control layer protocol of CAN. Thus the mechanism can be implemented dynamically while the data transactions are going on without any hardware modification. The CAN protocol was originally developed to be used in the automotive industry and it was recently applied for a broader class of automated factories. Even though CAN is able to satisfy most of real-time requirements found in automated environments, it is not to enforce either a fair subdivision of the network bandwidth among the stations or a satisfactory distribution of the access delays in message transmissions. The proposed solution provides a superset of the CAN logical link layer control, which can coexist with the older CAN applications. Through the real experiments, effectiveness of the proposed mechanism is verified.

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A MAC Protocol for Integrated Service in the Multi-Hop Ad-Hoc Maritime Communication Network (다중 홉 해양통신망에서 실시간 통합 서비스를 위한 MAC 프로토콜)

  • Cho, Kumin;Yun, Changho;Lim, Yong-Kon;Kang, Chung G.
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.7
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    • pp.603-611
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    • 2013
  • In this paper, we propose a new frame structure and the underlying dynamic resource control mechanism to support an integrated service, including a real-time (RT) service that requires to serve the end-to-end delay performance, as well as non-real-time (NRT) service, using Self-Organizing Time Division Multiple Access (SO-TDMA)-based MAC protocol in a multi-hop ad-hoc maritime communication network. The underlying frame structure is dynamically configured by resource allocation to guarantee the average target outage performance of the real-time service. Toward this end, we analyze the average outage probability and its performance is verified for the proposed frame structure by simulation.

Real-time Vehicle Recognition Mechanism using Support Vector Machines (SVM을 이용한 실시간 차량 인식 기법)

  • Chang, Jae-Khun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.7 no.6
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    • pp.1160-1166
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    • 2006
  • The information of vehicle is very important for maintaining traffic order under the present complex traffic environments. This paper proposes a new vehicle plate recognition mechanism that is essential to know the information of vehicle. The proposed method uses SVM which is excellent object classification compare to other methods. Two-class SVM is used to find the location of vehicle plate and multi-class SVM is used to recognize the characters in the plate. As a real-time processing system using multi-step image processing and recognition process this method recognizes several different vehicle plates. Through the experimental results of real environmental image and recognition using the proposed method, the performance is proven.

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Investment Decisions for Clean Development Mechanism under Uncertain Energy Policies using Real Option

  • Taeil Park;Changyoon Kim;Hyoungkwan Kim
    • International conference on construction engineering and project management
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    • 2013.01a
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    • pp.107-110
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    • 2013
  • Recently, Korea parliament legislated the Low Carbon Green Growth Act (April, 2012) and approved a bill (May, 2012) to start carbon emission trading system in 2015. It means that for the first time, government would regulate the amounts of carbon emission in private entities, and private entities should attain predefined emission reduction goals by implementing clean development mechanism (CDM) project or buy the Certified Emission Reductions (CERs) from the trading market to avoid penalty. Under these circumstances, it is not easy for them to determine when or how to implement the CDM project because the governmental energy policies about the level of governmental subsidies, periods for free emission allocation, etc. are still under discussion and the future price of the CERs is quite uncertain. Thus, this study presents a real-option based model to assess the financial viability of the CDM project which switches bunker-C oil to liquefied natural gas (LNG). The proposed model is expected to assist private entities in establishing the investment strategy for CDM project under uncertain government energy policies.

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