• Title/Summary/Keyword: Network Socket

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The research for human bio-signal monitoring smart home system (생체신호 모니터링 스마트 홈 모니터링에 관한 연구)

  • Kim, Kuk-Se;Kwon, Young-Sun;Lee, Ho-Young;Lee, Joon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.12 no.11
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    • pp.2097-2104
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    • 2008
  • Ubiquitous services are high duality and differentiated services which are provided for users by recognizing the context of users and environmental conditions actively. In this case, context-aware middleware is one of the most important technologies required to implement the ubiquitous services. In this paper, we propose a method for providing ubiquitous services in a specific user space effectively and monitoring human bio-signal sensors. That is, the design and implementation of intelligent home service middleware and monitoring human bio-signal sensor based on context awareness is discussed here. Context information from various sensors is gathered, and suitable services are inferred and provided to users by the middleware system. In our approach, user services can be modelled easily by using facts and rules, and the system can be extended easily to support various ubiquitous services other than intelligent home services also. The system can be integrated with external applications and legacy systems effectively by using various protocols such as RMI, socket and HTTP, XML and Zigbee etc. We have designed and evaluated various facts and rules for intelligent home services in real environments. Functionality evaluation with the system shows that ubiquitous services can be provided to users effectively in a home environment.

Implementation and Performance Testing of a Broadcasting System using Webcams and Smartphones (웹캠과 스마트폰을 이용한 브로드 캐스팅 시스템 구현 및 성능 실험)

  • Kim, Jeong-Myeong;Park, Geun-Duk
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.12
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    • pp.35-43
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    • 2013
  • This paper suggests a way to implement a system that broadcasts compressed JPEG images obtained from a webcam to multiple users on their smartphones. The system was implemented to maintain a suitable image quality so that things are identifiable while using the minimal amount of data, in order to deliver as many frames as possible to as many users as possible. Also, the suggested way was applied and various tests were done, including on: the performance of the server that provides image information; the performance of the client that receives the image information and displays it on the smartphone; and the max. number of simultaneous users supported by the system. When a broadcasting system is implemented using webcams and smartphones, the results of this paper can be used in estimating the suitable system parameters depending on network performance, including the max. number of simultaneous clients supported, the client smartphone performance required, and the number of frames that can be transmitted per second.

Performance Evaluation of Workstation System within ATM Integrated Service Switching System using Mean Value Analysis Algorithm (MVA 알고리즘을 이용한 ATM 기반 통합 서비스 교환기 내 워크스테이션의 성능 평가)

  • Jang, Seung-Ju;Kim, Gil-Yong;Lee, Jae-Hum;Park, Ho-Jin
    • Journal of KIISE:Computing Practices and Letters
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    • v.6 no.4
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    • pp.421-429
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    • 2000
  • In present, ATM integrated switching system has been developed to a mixed modules that complexed switching system including maintenance, operation based on B-ISDN/LAN service and plug-in module, , which runs on workstation computer system. Meanwhile, workstation has HMI operation system feature including file system management, time management, graphic processing, TMN agent function. The workstation has communicated with between ATM switching module and clients. This computer system architecture has much burden messages communication among processes or processor. These messages communication consume system resources which are socket, message queue, IO device files, regular files, and so on. Therefore, in this paper we proposed new performance modeling with this system architecture. We will analyze the system bottleneck and improve system performance. In addition, in the future, the system has many additional features should be migrated to workstation system, we need previously to evaluate system bottleneck and redesign it. In performance model, we use queueing network model and the simulation package is used PDQ and C-program.

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Web-based Measurement of ECU Signals on Vehicle using Embedded Linux

  • Choi, Kwang-Hun;Lee, Lee;Lee, Young-Choon;Kwon, Tae-Kyu;Lee, Seong-Cheol
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.138-142
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    • 2004
  • In this paper, we present a new method for monitoring of ECU's sensor signals of vehicle. In order to measure the ECU's sensor signals, the interfaced circuit is designed to communicate ECU and the Embedded Linux is used to monitor communication result through Web the Embedded Linux system and this system is said "ECU Interface Part". In ECU Interface Part the interface circuit is designed to match voltage level between ECU and SA-1110 micro controller and interface circuit to communicate ECU according to the ISO, SAE communication protocol standard. Because Embedded Linux does not allow to access hardware directly in application level, anyone who wants to modify any low level hardware must develop device driver. To monitor ECU's sensor signals the most important thing is to match serial level between ECU and ECU Interface Part. It means to communicate correctly between two hardware we need to match voltage and signal level, and need to match baudrate. The voltage of SA-1110 is 0 ${\sim}$ +3.3V and ECU is 0 ${\sim}$ +12V and, ECU's communication Line K does multiple operation so, the interface circuit is used to match voltage and signal level. In Addition to ECU's baudrate is 10400bps, it's not standard baudrate in computer environment. So, we need to develop a device driver to control the interface circuit, and change baudrate. To monitor ECU's sensor signals through web there's a network socket program is working in Embedded Linux. It works as server program and manages user's connections and commands. Anyone who wants to monitor ECU's sensor signals he just only connect to Embedded Linux system with web browser then, Embedded Linux webserver will return the ActiveX webbased measurement software. It works in web browser and inits ECU, as a result it returns sensor signals through web. All the programs are developed with GCC(GNU C Compiler) and, webbased measurement software is developed with Borland C++ Builder.

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An Improvement of Performance for Data Downstream in IEEE 802.11x Wireless LAN Networks (IEEE 802.11x 무선 랜에서의 데이터 다운스트림 성능 향상)

  • Kim, Ji-Hong;Kim, Yong-Hyun;Hong, Youn-Sik
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.43 no.11 s.353
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    • pp.149-158
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    • 2006
  • We proposed a method for improving a performance of TCP downstream between a desktop PC as a fixed host and a PDA as a mobile host in a wired and wireless network based on IEEE 802.11x wireless LAN. With data transmission between these heterogeneous terminals a receiving time during downstream is slower than that during upstream by 20% at maximum. The reason is that their congestion window size will be oscillated due to a significantly lower packet processing rate at receiver compared to a packet sending rate at sender. Thus it will cause to increase the number of control packets to negotiate their window size. To mitigate these allergies, we proposed two distinct methods. First, by increasing a buffer size of a PDA at application layer an internal processing speed of a socket receive buffer of TCP becomes faster and then the window size is more stable. However, a file access time in a PDA is kept nearly constant as the buffer size increases. With the buffer size of 32,768bytes the receiving time is faster by 32% than with that of 512bytes. Second, a delay between packets to be transmitted at sender should be given. With an inter-packet delay of 5ms at sender a resulting receiving time is faster by 7% than without such a delay.

A Design of Service Migration Mechanism in HTML5-based Convergence Service (HTML5 기반 융합 서비스의 서비스이동 메커니즘 설계)

  • Choi, Hun-Hoi;Song, Eun-Ji;Kim, Geun-Hyung;Kim, Hwa-Sook;Cho, Ki-Seong
    • Journal of Korea Multimedia Society
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    • v.15 no.4
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    • pp.540-551
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    • 2012
  • Recently, the W3C has developed the HTML5 standard which gives the basis for providing various web applications on the web environments. Because of the advent of the smart devices and the broadband wireless network, users can accesse the web applications on the smart devices at anytime and anywhere. In addition, the demand on the multiscreen services, which enables users to use the appropriate device to their situation, has increased, since users have various smart devices. In this paper, we propose the grouping mechanism of web objects on the HTML5 based web platform, the extraction mechanism of the web object information which is used to create the web object on other devices, and the web object creation mechanism based on the received web object information. In addition, we propose the web service migration architecture between devices on the open web platform and implement the grouping, extraction and creation mechanism of the web objects on the test web document and generic web document with Chrome extension. Finally, we implement the delivery mechanism of the web object information between devices using the node.js and the WebSocket technologies.

A Design of a Network Module supporting Primitive Messaging Operations for MOM (MOM의 Primitive Messaging Operation을 지원하는 네트워크 모듈 설계)

  • Kang, Tae-Gun;Sohn, Kang-Min;Ham, Ho-Sang
    • Proceedings of the Korea Information Processing Society Conference
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    • 2003.11a
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    • pp.115-118
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    • 2003
  • 최근 MOM 기술은 비즈니스 로직을 수행하는 애플리케이션 서버의 필수적인 구성요소로서 자리잡고 있으며, 보통 수백에서 수천의 클라이언트 요청을 처리할 수 있는 능력을 제공한다. MOM 은 이러한 대용량의 클라이언트 요청을 효과적으로 처리하기 위해서 효율적이고 확장성있는(스케일러블) 네트워크 모듈이 필요하며, 다양한 네트워크 프로토콜을 지원해야 한다. MOM이 기본적으로 지원하는 메시징 기능은 PTP(Point-To-Point)와 publish/subscribe 메시징 도메인으로 나뉘는데 이 논문에서는 두 가지 메시징 도메인과 그룹통신 메시징 서비스 기능을 동시에 지원하는 MoIM-Message 시스템의 하부 통신 모듈의 설계에 대해 기술한다. PTP와 publish/subscribe 메시징을 지원하기 위해 세가지 프리미티브 메시징 오퍼레이션인 "synchronous send", "synchronous receive", "asynchronous receive"를 정의하였으며 하부 통신 모듈 역할을 하는 메시지 트랜스포트 관리 계층내의 트랜스포트 관리자 내에 구현되었다. 트랜스포트 관리자는 다양한 트랜스포트 프로토콜을 적용할 수 있도록 하기 위해 트랜스포트 어댑터로 설계되었으며, 대량의 통신 요청을 효과적으로 처리하기 위해 "polling with multiple service thread model" 기법을 적용하여 구현되었다. 또한, 모바일 클라이언트 환경을 지원하기 위해 클라이언트 측 통신 모듈을 IPaq PDA 상에 포팅하였다. 본 논문에서 제안하는 세 가지 프리미티브 메시징 오퍼레이션을 제공하는 통신 모듈은 MOM이 기본적으로 지원해야 할 메시징 도메인과 대용량의 클라이언트 요청을 효율적으로 처리할 수 있는 구조를 가진다.es}8$ 모드를 모두 사용한 경우와 $8{\times}8$ 단일모드를 사용한 경우보다 계산 시간이 감소하였음을 확인하였다.행중인 MoIM-Messge서버의 네트워크 모듈로 다중 쓰레드 소켓폴링 모델을 적용하였다.n rate compared with conventional face recognition algorithms. 아니라 실내에서도 발생하고 있었다. 정량한 8개 화합물 각각과 총 휘발성 유기화합물의 스피어만 상관계수는 벤젠을 제외하고는 모두 유의하였다. 이중 톨루엔과 크실렌은 총 휘발성 유기화합물과 좋은 상관성 (톨루엔 0.76, 크실렌, 0.87)을 나타내었다. 이 연구는 톨루엔과 크실렌이 총 휘발성 유기화합물의 좋은 지표를 사용될 있고, 톨루엔, 에틸벤젠, 크실렌 등 많은 휘발성 유기화합물의 발생원은 실외뿐 아니라 실내에도 있음을 나타내고 있다.>10)의 $[^{18}F]F_2$를 얻었다. 결론: $^{18}O(p,n)^{18}F$ 핵반응을 이용하여 친전자성 방사성동위원소 $[^{18}F]F_2$를 생산하였다. 표적 챔버는 알루미늄으로 제작하였으며 본 연구에서 연구된 $[^{18}F]F_2$가스는 친핵성 치환반응으로 방사성동위원소를 도입하기 어려운 다양한 방사성의 약품개발에 유용하게 이용될 수 있을 것이다.었으나 움직임 보정 후 영상을 이용하여 비교한 경우, 결합능 변화가 선조체 영역에서 국한되어 나타나며 그 유의성이 움직임 보정 전에 비하여 낮음을 알 수 있었다. 결론: 뇌활성화 과제 수행시에 동반되는 피험자의 머리 움직임에 의하여 도파민 유리가 과대평가되었으며 이는 이 연구에서 제안한 영상정합을 이용한 움직임 보정기법에

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A Study of Future Internet Testbed Construction using NetFGA/OpenFlow Switch on KOREN/KREONET (KOREN/KREONET기반 NetFPGA/OpenFlow 스위치를 이용한 미래인터넷 테스트 베드 구축 방안 연구)

  • Park, Man-Kyu;Jung, Whoi-Jin;Lee, Jae-Yong;Kim, Byung-Chul
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.47 no.7
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    • pp.109-117
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    • 2010
  • Building a large-scale testbed for Future Internet is very important to evaluate a new protocol and new network architecture designed by clean-slate approach. In Korea, new Future Internet testbed project, called FIRST (Future Internet Research for Sustainable Testbed), has been started since Mar. 2009 to design and test new protocols. This project is working together with ETRI and 5 universities. The FIRST@PC is to implement a virtualized hardware-accelerated PC-node by extending the functions of NetFPGA card and build a Future Internet testbed on the KOREN and KREONET for evaluating newly designed protocols and interesting applications. In this paper, we first briefly introduce FIRST@PC project and explain a 'MAC in IP Capsulator' user-space program using raw-socket in Linux to interconnect OpenFlow enabled switch sites on the KOREN and KREONET. After that, we address test results for TCP throughput performance for varying packet size. The test results show that the software based capsulator can support a reasonable bandwidth performance for most of applications.

A Design and Implementation of ZigBee Educational System in USN Environment (USN환경에서 교육용 ZigBee 장비의 설계 및 구현)

  • Park, Gyun Deuk;Chung, Joong Soo;Jung, Kwang Wook
    • KIPS Transactions on Software and Data Engineering
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    • v.2 no.5
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    • pp.335-340
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    • 2013
  • This paper has designed and realized educational ZigBee equipment befitting to the USN environment. In addition, this study has enabled users to exercise operation process for software technology education and to propose software design methods in the process in the USN environment through practice equipment for ZigBee education. As for the development environment of system, Atmega128 process of Atmel is used for CPU; AVR compiler for the debugging environment; C language for firmware development language; and C++ for application program. The system operation process is initiated by coordinator's sensing information reading order from the hyper terminal through a server through the Internet or directly connected; and then delivering it to a terminating device by using ZigBee technology. The terminating device delivers various sensing information to the coordinator which delivers it to a server through the Internet or to a HYPER terminal directly connected to the coordinator. As for the educational course, it is about practices on such ZigBee operation process and relevant programing skills. Regarding it, the communication between coordinator and terminating device is designed by utilizing physical layer of ZigBee protocol, MAC layer and network layer while the communication between server and coordinator is designed by proposing an independent protocol on TCP/IP socket and the protocol processing procedure during sensing data delivery is verified by interpretation.