• Title/Summary/Keyword: real-time network

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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).

Human Motion Tracking With Wireless Wearable Sensor Network: Experience and Lessons

  • Chen, Jianxin;Zhou, Liang;Zhang, Yun;Ferreiro, David Fondo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.5
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    • pp.998-1013
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    • 2013
  • Wireless wearable sensor networks have emerged as a promising technique for human motion tracking due to the flexibility and scalability. In such system several wireless sensor nodes being attached to human limb construct a wearable sensor network, where each sensor node including MEMS sensors (such as 3-axis accelerometer, 3-axis magnetometer and 3-axis gyroscope) monitors the limb orientation and transmits these information to the base station for reconstruction via low-power wireless communication technique. Due to the energy constraint, the high fidelity requirement for real time rendering of human motion and tiny operating system embedded in each sensor node adds more challenges for the system implementation. In this paper, we discuss such challenges and experiences in detail during the implementation of such system with wireless wearable sensor network which includes COTS wireless sensor nodes (Imote 2) and uses TinyOS 1.x in each sensor node. Since our system uses the COTS sensor nodes and popular tiny operating system, it might be helpful for further exploration in such field.

Real-time Air Quality Monitoring System Based on Wireless Network (무선네트워크기반 공기질 실시간 모니터링 시스템)

  • Paik, Seung Hyun;Lee, Jun Yeong;Jung, Sang Woo;Park, Hong Bae
    • IEMEK Journal of Embedded Systems and Applications
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    • v.11 no.3
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    • pp.143-151
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    • 2016
  • In this paper, a real-time air quality monitoring system based on wireless network is designed and implemented for industrial park or multiuse facilities. The existing gas detector is high price and hard to apply the remote monitoring system. On the other hand, demand for air quality monitoring is increasing because of industrial gas accident, air pollution, and so on. In Korea, indoor air regulation was established by law. According to indoor air regulation, CO2, CO, and NO2 are important gases as the air quality standard. So we study the gas detector for indoor air quality and the wireless network system. The wireless network consist of sensor network and WCDMA to apply various place. To verify the performance of the implemented gas detector, the gas measurement experiment is performed in laboratory environment by using the realized gas detecting wireless sensor node. And we evaluate the experiment results.

Development of Network Event Audit Module Using Data Mining (데이터 마이닝을 통한 네트워크 이벤트 감사 모듈 개발)

  • Han, Seak-Jae;Soh, Woo-Young
    • Convergence Security Journal
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    • v.5 no.2
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    • pp.1-8
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    • 2005
  • Network event analysis gives useful information on the network status that helps protect attacks. It involves finding sets of frequently used packet information such as IP addresses and requires real-time processing by its nature. Apriori algorithm used for data mining can be applied to find frequent item sets, but is not suitable for analyzing network events on real-time due to the high usage of CPU and memory and thus low processing speed. This paper develops a network event audit module by applying association rules to network events using a new algorithm instead of Apriori algorithm. Test results show that the application of the new algorithm gives drastically low usage of both CPU and memory for network event analysis compared with existing Apriori algorithm.

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Load Balancing for Zone Routing Protocol to Support QoS in Ad Hoc Network

  • Chimmanee, Sanon;Wipusitwarakun, Komwut;Runggeratigul, Suwan
    • Proceedings of the IEEK Conference
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    • 2002.07c
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    • pp.1685-1688
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    • 2002
  • Application Routing Load Balancing (ARLB) is a novel load balancing mode that combines QoS routing and load balancing in per application to support QoS far real-time application based on wired network. Zone Routing Protocol (ZRP) is a recent hybrid proactive/reactive routing approach in an attempt to achieve scalability of ad-hoc network. This routing approach has the potential to be efficient in the generation of control traffic than traditional routing schemes. Up to now, without proper load balancing tools, the ZRP can actually guarantee QoS for delay-sensitive applications when congestion occurred in ad-hoc network. In this paper, we propose the ARLB to improve QoS fur delay-sensitive applications based on ZRP in ad-hoc network when congestion occurred and to be forwarding mechanism fur route coupling to support QoS for real-time applications. The critical point is that the routing metric of ARLB is originally designed for wired network environment. Therefore, we study and present an appropriate metric or cost computation routing of ARLB for recently proposed ZRP over ad-hoc network environment.

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A Robust Wearable u-Healthcare Platform in Wireless Sensor Network

  • Lee, Seung-Chul;Chung, Wan-Young
    • Journal of Communications and Networks
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    • v.16 no.4
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    • pp.465-474
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    • 2014
  • Wireless sensor network (WSN) is considered to be one of the most important research fields for ubiquitous healthcare (u-healthcare) applications. Healthcare systems combined with WSNs have only been introduced by several pioneering researchers. However, most researchers collect physiological data from medical nodes located at static locations and transmit them within a limited communication range between a base station and the medical nodes. In these healthcare systems, the network link can be easily broken owing to the movement of the object nodes. To overcome this issue, in this study, the fast link exchange minimum cost forwarding (FLE-MCF) routing protocol is proposed. This protocol allows real-time multi-hop communication in a healthcare system based on WSN. The protocol is designed for a multi-hop sensor network to rapidly restore the network link when it is broken. The performance of the proposed FLE-MCF protocol is compared with that of a modified minimum cost forwarding (MMCF) protocol. The FLE-MCF protocol shows a good packet delivery rate from/to a fast moving object in a WSN. The designed wearable platform utilizes an adaptive linear prediction filter to reduce the motion artifacts in the original electrocardiogram (ECG) signal. Two filter algorithms used for baseline drift removal are evaluated to check whether real-time execution is possible on our wearable platform. The experiment results shows that the ECG signal filtered by adaptive linear prediction filter recovers from the distorted ECG signal efficiently.

Design and Implementation of Receiver Network Elements for Real-Time Precise GPS/GNSS (실시간 정밀 GPS/GNSS를 위한 위성항법 수신기 망 구성 요소 설계 및 구현)

  • Kim, Hee-Sung;Lee, Hyung-Keun
    • Journal of Institute of Control, Robotics and Systems
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    • v.16 no.2
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    • pp.126-133
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    • 2010
  • Due to the deployment of various wireless networks originating from CDMA, GSM, and WLAN, it became very convenient to exchange information from one place to another. As compared with the traditional environments for one-way information distribution based on fixed radio frequency bands, the convenient wireless network environments will bring about many changes in positioning technologies based on global navigation satellites. Among the many changes to come, the reconfigurable receiver network is one of the most attractive concepts since it can be tailored to a specific application area among networked robots, formation flying, bridge monitoring, and traffic monitoring. As an initial study to develop a reconfigurable receiver network, this paper deals with the design and implementation of the key elements of the reconfigurable receiver netowork; server, broadcaster, and client. In the designed receiver network, a sever receives and decodes measurements from a reference receiver installed at a known location, a broadcaster processes and transfers the messages from servers to clients and manages connections with servers and clients, a client receives the messages from the broadcaster and performs differential positioning. A real-time experiment result is demonstrated to validate the functionalities of each network element.

Augmented Reality Annotation for Real-Time Collaboration System

  • Cao, Dongxing;Kim, Sangwook
    • Journal of Korea Multimedia Society
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    • v.23 no.3
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    • pp.483-489
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    • 2020
  • Advancements in mobile phone hardware and network connectivity made communication becoming more and more convenient. Compared to pictures or texts, people prefer to share videos to convey information. For intentions clearer, the way to annotating comments directly on the video are quite important issues. Recently there have been many attempts to make annotations on video. These previous works have many limitations that do not support user-defined handwritten annotations or annotating on local video. In this sense, we propose an augmented reality based real-time video annotation system which allowed users to make any annotations directly on the video freely. The contribution of this work is the development of a real-time video annotation system based on recent augmented reality platforms that not only enables annotating drawing geometry shape on video in real-time but also drastically reduces the production costs. For practical use, we proposed a real-time collaboration system based on the proposed annotation method. Experimental results show that the proposed annotation method meets the requirements of real-time, accuracy and robustness of the collaboration system.

Reinforcement Method to Enhance Adaptive Route Search for Efficient Real-Time Application Specific QoS Routing (Real-Time Application의 효과적인 QoS 라우팅을 위한 적응적 Route 선택 강화 방법)

  • Oh, Jae-Seuk;Bae, Sung-Il;Ahn, Jin-Ho;Sungh Kang
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.40 no.12
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    • pp.71-82
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    • 2003
  • In this paper, we present a new method to calculate reinforcement value in QoS routing algorithm targeted for real-time applications based on Ant algorithm to efficiently and effectively reinforce ant-like mobile agents to find the best route toward destination in a network regarding necessary QoS metrics. Simulation results show that the proposed method realizes QoS routing more efficiently and more adaptively than those of the existing method thereby providing better solutions for the best route selection for real-time application that has high priority on delay jitter and bandwidth.

Vehicle Detection in Dense Area Using UAV Aerial Images (무인 항공기를 이용한 밀집영역 자동차 탐지)

  • Seo, Chang-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.3
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    • pp.693-698
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    • 2018
  • This paper proposes a vehicle detection method for parking areas using unmanned aerial vehicles (UAVs) and using YOLOv2, which is a recent, known, fast, object-detection real-time algorithm. The YOLOv2 convolutional network algorithm can calculate the probability of each class in an entire image with a one-pass evaluation, and can also predict the location of bounding boxes. It has the advantage of very fast, easy, and optimized-at-detection performance, because the object detection process has a single network. The sliding windows methods and region-based convolutional neural network series detection algorithms use a lot of region proposals and take too much calculation time for each class. So these algorithms have a disadvantage in real-time applications. This research uses the YOLOv2 algorithm to overcome the disadvantage that previous algorithms have in real-time processing problems. Using Darknet, OpenCV, and the Compute Unified Device Architecture as open sources for object detection. a deep learning server is used for the learning and detecting process with each car. In the experiment results, the algorithm could detect cars in a dense area using UAVs, and reduced overhead for object detection. It could be applied in real time.