• Title/Summary/Keyword: real-time mechanism

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Implementation of Real-Time Communication in CAN for a Humanoid Robot (CAN 기반 휴머노이드 로봇의 실시간 데이터 통신 구현)

  • Kwon Sun-Ku;Kim Byung-Yoon;Kim Jin-Hwan;Huh Uk-Youl
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.55 no.1
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    • pp.24-30
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    • 2006
  • The Controller Area Network (CAN) is being widely used for real-time control application and small-scale distributed computer controller systems. When the stuff bits are generated by bit-stuffing mechanism in the CAN network, it causes jitter including variations in response time and delay In order to eliminate this jitter, stuff bits must be controlled to minimize the response time and to reduce the variation of data transmission time. This paper proposes the method to reduce the stuff bits by restriction of available identifier and bit mask using exclusive OR operation. This da manipulation method are pretty useful to the real-time control strategy with respect to performance. However, the CAN may exhibit unfair behavior under heavy traffic conditions. When there are both high and low priority messages ready for transmission, the proposed precedence priority filtering method allows one low priority message to be exchanged between any two adjacent higher priority messages. In this way, the length of each transmission delays is upper bounded. These procedures are implemented as local controllers for the ISHURO(Inha Semvung Humanoid Robot).

A Study on the Design of Hardware Switching Mechanism using TCP/IP Communication (TCP/IP를 이용한 하드웨어 전환장치 설계에 관한 연구)

  • Kim, Chong-Sup;Cho, In-Je;Lim, Sang-Soo;Ahn, Jong-Min;Kang, Im-Ju
    • Journal of Institute of Control, Robotics and Systems
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    • v.13 no.7
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    • pp.694-702
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    • 2007
  • The SSWM(Software Switching Mechanism) of I-processor concept using non-real time in-house software simulation program is an effective method in order to develop the flight control law in desktop or HQS environment. And, this system has some advantages compare to HSWM(Hardware Switching Mechanism) such as remove the time delay effectiveness and reduce the costs of development. But, if this system loading to the OFP(Operational Flight Program), the OFP guarantee the enough throughput in order to calculate the two control law at once. Therefore, the HSWM(Hardware Switching Mechanism) of 2-processor concept is necessary. This paper addresses the concept of HSWM of the HQS-PC interface using TCP/IP(Transmission Control Protocol/Internet Protocol) communication based on flight control law of advanced supersonic trainer. And, the fader logic of TFS(Transient Free Switch) and stand-by mode of reset '0' type are designed in order to reduce the abrupt transient response and minimize the integrator effect in pitch axis. The result of the analysis based on HQS pilot simulation using HSWM reveals that the flight control systems are switching between two computers without any problem.

Distributed Control Algorithms for QoS in Wireless Networks Using Wireless Token Ring Protocol (무선토큰링 프로토콜을 사용한 무선 네트워크에서 QoS를 지원하는 분산 제어 알고리즘)

  • 김성철
    • Journal of Korea Multimedia Society
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    • v.7 no.2
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    • pp.187-193
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    • 2004
  • Wireless networks play a very important role in communications today. For example, wireless networks today provide from the basic services like e-mail and FTP to the multimedia applications like Web service. It is obvious that QoS requirements to these diverse applications over wireless networks will continue as in wired networks. Much research has been done to develop QoS supporting algorithms on Internet. But due to the limited bandwidth and varying channel states of the wireless networks, it is difficult to support differentiated service over wireless networks. In this paper we propose the modified wireless token ring protocol supporting QoS to the real-time traffic service node over Internet environments in which non-real-time and real-time traffic service nodes coexist. In the proposed algorithm, the real-time traffic service node gets the priority to take token over the non-real-time traffic service node. So the proposed algorithm support quick transmission of the real-time traffic service node. And this advantage can be obtained with minor modification of the legacy wireless token ing protocol to support QoS. We also consider the lost token recovery mechanism.

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Distributed simulation on a network as a CIM developing tool (CIM 구축 tool 로서의 네트워크 상의 분산시뮬레이션)

  • 김성식;배경한
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10a
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    • pp.799-803
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    • 1991
  • This study proposes a CIM shell that is consisted with computers connected by a LAN. Since this system excludes production hardwares, physical movements of devices are represented by computer simulation. On the other hand, softwares that dictate system operation are real, and consu- me physical time. Thus the shell becomes half-real-half-simulation that requires events synchronization mechanism. This study shows the building procedure of such shell as well as an example of application of the shell.

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Real-time Vehicle License Plate Recognition Method using Vehicle-loaded Camera (차량 탑재용 카메라를 이용한 실시간 차량 번호판 인식 기법)

  • Chang, Jae-Khun
    • Journal of Internet Computing and Services
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    • v.6 no.3
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    • pp.147-158
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    • 2005
  • Day after day the information of vehicle under the complex traffic environments is greatly required not only for traffic flow but also for vehicle disclosure of traffic violation, Vehicle information can be obtained from a recognition of vehicle license plate, This paper proposes a new vehicle plate recognition mechanism that uses moving style vehicle-loaded camera, The method is a real-time processing system using multi-step image processing and recognition process that recognizes general vehicles and special purpose vehicles, The experimental results of real environmental image and recognition using the proposed method are shown.

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A Network Coding-Aware Routing Mechanism for Time-Sensitive Data Delivery in Multi-Hop Wireless Networks

  • Jeong, Minho;Ahn, Sanghyun
    • Journal of Information Processing Systems
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    • v.13 no.6
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    • pp.1544-1553
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    • 2017
  • The network coding mechanism has attracted much attention because of its advantage of enhanced network throughput which is a desirable characteristic especially in a multi-hop wireless network with limited link capacity such as the device-to-device (D2D) communication network of 5G. COPE proposes to use the XOR-based network coding in the two-hop wireless network topology. For multi-hop wireless networks, the Distributed Coding-Aware Routing (DCAR) mechanism was proposed, in which the coding conditions for two flows intersecting at an intermediate node are defined and the routing metric to improve the coding opportunity by preferring those routes with longer queues is designed. Because the routes with longer queues may increase the delay, DCAR is inefficient in delivering real-time multimedia traffic flows. In this paper, we propose a network coding-aware routing protocol for multi-hop wireless networks that enhances DCAR by considering traffic load distribution and link quality. From this, we can achieve higher network throughput and lower end-to-end delay at the same time for the proper delivery of time-sensitive data flow. The Qualnet-based simulation results show that our proposed scheme outperforms DCAR in terms of throughput and delay.

A study on real time inspection of OLED protective film using edge detecting algorithm (Edge Detecting Algorithm을 이용한 OLED 보호 필름의 Real Time Inspection에 대한 연구)

  • Han, Joo-Seok;Han, Bong-Seok;Han, Yu-Jin;Choi, Doo-Sun;Kim, Tae-Min;Ko, Kang-Ho;Park, Jung-Rae;Lim, Dong-Wook
    • Design & Manufacturing
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    • v.14 no.2
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    • pp.14-20
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    • 2020
  • In OLED panel production process, it is necessary to cut a part of protective film as a preprocess for lighting inspection. The current method is to recognize only the fiducial mark of the cut-out panel. Bare Glass Cutting does not compensate for machining cumulative tolerances. Even though process defects still occur, it is necessary to develop technology to solve this problem because only the Align Mark of the panel that has already been cut is used as the reference point for alignment. There is a lot of defective lighting during panel lighting test because the correct protective film is not cut on the panel power and signal application pad position. In laser cutting process to remove the polarizing film / protective film / TSP film of OLED panel, laser processing is not performed immediately after the panel alignment based on the alignment mark only. Therefore, in this paper, we performed real time inspection which minimizes the mechanism tolerance by correcting the laser cutting path of the protective film in real time using Machine Vision. We have studied calibration algorithm of Vision Software coordinate system and real image coordinate system to minimize inspection resolution and position detection error and edge detection algorithm to accurately measure edge of panel.

Malicious Trojan Horse Application Discrimination Mechanism using Realtime Event Similarity on Android Mobile Devices (안드로이드 모바일 단말에서의 실시간 이벤트 유사도 기반 트로이 목마 형태의 악성 앱 판별 메커니즘)

  • Ham, You Joung;Lee, Hyung-Woo
    • Journal of Internet Computing and Services
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    • v.15 no.3
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    • pp.31-43
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    • 2014
  • Large number of Android mobile application has been developed and deployed through the Android open market by increasing android-based smart work device users recently. But, it has been discovered security vulnerabilities on malicious applications that are developed and deployed through the open market or 3rd party market. There are issues to leak user's personal and financial information in mobile devices to external server without the user's knowledge in most of malicious application inserted Trojan Horse forms of malicious code. Therefore, in order to minimize the damage caused by malignant constantly increasing malicious application, it is required a proactive detection mechanism development. In this paper, we analyzed the existing techniques' Pros and Cons to detect a malicious application and proposed discrimination and detection result using malicious application discrimination mechanism based on Jaccard similarity after collecting events occur in real-time execution on android-mobile devices.

A Study on Production Mechanism of Meta-Knowledge for Effectively Managing Contents and Models (컨텐츠 및 모델의 효과적 관리를 위한 메타-지식 생성 메커니즘 연구)

  • Kim, Chul-Soo
    • The KIPS Transactions:PartB
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    • v.8B no.5
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    • pp.441-446
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    • 2001
  • On global interconnectivity, the activation of real-time and worldwide contents will permeate and impact all aspects of day-to-day life well throughout this century. In managing contents and models, we too will see the impact of this rapidly changing environment. The real time availability of contents pertaining to a companys supply chain through means of the Internet and mobile networks(e.g., the IMT-2000) will necessitate a change in decision-making processes for effective management of contents and models. To increase the availability of many contents and models, a management system should have adaptive function in proving adequate content and model for companies. In the respect of management of contents and models, this paper discusses a production mechanism of meta-knowledge for effectively managing contents and models. Through two experimental analyses with the production mechanism, it is proven that the system enabling adaptive contents and models provision goes beyond existing ones in view of efficiency of management of contents and models in the wire and wireless networks.

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