• Journal of the Semiconductor & Display Technology
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• v.21 no.3
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• pp.26-32
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• 2022

EtherCAT is an Ethernet-based fieldbus system standardized in IEC 61158 and SEMI, and widely used in the fields of factory automation, semiconductor equipment and robotics. In this paper, an EtherCAT master is implemented on an embedded board with Arm based 64-bit quad-core processor and its jitter performance is evaluated at the output of the network interface to include all the effects of the entire system in the results. For the EtherCAT master system, an open source EtherCAT master stack, Simple Open EtherCAT Master (SOEM), is installed on PREEMPT_RT patched Linux operating system for real-time operation. The results show that the jitter performance is comparable to that of Xenomai-based master and the EtherCAT master with two master instances has similar jitter performance to the EtherCAT master with one master instance.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.7
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• pp.303-312
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• 2006

This paper proposes the architecture and protocol of a data communication network for the safety system in nuclear power plants. First, we establish four design criteria with respect to determinability, reliability, separation and isolation, and verification/validation. Next we construct the architecture of the safety network for the following systems: PPS (Plant Protection System), ESF-CCS (Engineered Safety Features-Component Control System) and CPCS (Core Protection Calculator System). The safety network consists of 12 sub-networks and takes the form of a hierarchical star. Among 163 communication nodes are about 1600 origin-destination (OD) pairs created on their traffic demands. The OD pairs are allowed to exchange data only during the pre-assigned time slots. Finally, the communication protocol is designed in consideration of design factors for the safety network. The design factors include a network topology of star, fiber-optic transmission media, synchronous data transfer mode, point-to-point link configuration, and a periodic transmission schedule etc. The resulting protocol is the modification of IEEE 802.15.4 (LR-WPAN) MAC combined with IEEE 802.3 (Fast Ethernet) PHY. The MAC layer of IEEE 802.15.4 is simplified by eliminating some unnecessary (unctions. Most importantly, the optional TDMA-like scheme called the guaranteed time slot (GTS) is changed to be mandatory to guarantee the periodic data transfer. The proposed protocol is formally specified using the SDL. By performing simulations and validations using Telelogic Tau SDL Suite, we find that the proposed safety protocol fits well with the characteristics and the requirements of the safety system in nuclear power plants.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.39 no.2
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• pp.110-117
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• 2002

These days, most of control system requires automazation in the all fields. Therefore OCS which can simplify control system integration is appearing. In this study, OCS consists of HMI, OS, Controller, and Communication network. (SFC and visual C++ are used as HMI, window NT is used as OS, pentium PC is used as Controller, and industrial Ethernet is used as Communication network.) Finally, We applied OCS to Level control system and Temperature control system, and verified its efficiency.

• The Transactions of the Korea Information Processing Society
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• v.7 no.6
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• pp.1941-1948
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• 2000

Multistage interconnection networks (MINs) have been recognized as an efficient interconnection network for high-performance computer systems and also have been recently identified to be effective for a switching fabric of new communication structures - gigabit ethernet switch, terabit router, and ATM (asynchronous transfer mode). While lots of models analyzing the performance of MINs have been proposed, they are either inaccurate or, even if accurate, very complex for the analysis. In this paper, we propose an extremely simple mode for evaluating the multibuffered MIN with small clock cycles based on the approximation approach. Comprehensive computer simulation shows that the proposed model is very accurate in terms of the throughput and mean delay. Furthermore, it significantly reduces the computing overhead due to its simplicity.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.8
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• pp.1415-1419
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• 2008

In this paper, we investigate various Audio Transmission Systems to implement Audio Transmission System based on AoIP of Internet transmission technology TCP/IP Network and we design and implement a Audio transmission system based on AoIP by adopting the most efficient one. The implemented system can be applied for various professional audio systems with large-scale audio distribution network as well as small-scale PA systems. Moreover, this can be applied in various fields which need audio transmission.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.12
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• pp.2165-2170
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• 2008

In this parer, it is implemented a Local distribution Audio System, based on AoIP(Audio over Internet Protocol) of a part of TCP/IP Network which belongs to Internet transmission technology. The system is controlled based on SNMP(Simple Network Management Protocol) and it is transferred to UDP as packet after changing from Analog audio sources to Digital audio sources. The implemented Local distribution Audio System have presented practical possibilities in PA system transmitting various audio sources to several areas, dispersedly and using multichannel audio like Home theaters in the limelight, recently.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.6
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• pp.1096-1101
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• 2004

By a tremendous expansion of Internet users, there's a number effects that cause the phenomenon of bottlenecked switching packets from routers. In order to tear down this problem, distributed system is applicable to almost every highly performed router systems. The main processor of distributed system, which manages routing table, commands IPC to delivering the forwarding table line processor that eases functionalities of the router. This makes the system having wired-speed forwarding function based on the hardware so that the performance of the network can be enhanced. Therefore, IPC, which assign a part of router, is necessary to exchange data smoothly and the constitution of IPC using Ethernet is widely adapted as a method for saving investment. In this paper, R-IPC mechanism improve the packet-processing rate over 10% through changed from defect of conventional Ethernet IPC, that is, 2 layer processing to TCP/IP or UDP/ IP into 1 layer processing for efficient packet forwarding.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.8 no.5
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• pp.71-84
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• 2009

The communication between the center system and the local controller in the Traffic Signal Controller Specification has been specified by a communication line for the exclusive use and the analog modem serial protocol. Therefore, it can't be adapted in the ITS communication network of the TCP/IP protocol being constructed in the local city. The international and domestic ITS device's communication specification has adapted the DATEX-ASN data exchange technique based on the ethernet communication network. So, this study was performed by the purpose of developing the application communication protocol's standard draft based on the TCP/IP communication protocol for the traffic signal controller, to be able to constitute the traffic signal control system in the ITS communication network. The communication format for 23 items of control, status, and database request etc. which are specified in the standard traffic signal controller was developed by appling the DATEX-ASN data interface procedure and structure which are KS ISO X 14827 Part1, 2, ISO/ DIS 15784 Part-3. To test the developed protocol, the application program for the communication items was developed and according to the test result, the encoding and the decoding transection for all communication items was possible.

• Journal of Korea Multimedia Society
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• v.11 no.7
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• pp.1007-1015
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• 2008

In order to provide real-time data from sensors and instruments at manufacturing processes on web, we proposed a communication service model based on XML(eXtensible Markup Language). HTML(Hyper Text Markup Language) is inadequate for describing real-time data from manufacturing plants while it is suitable for display of non-real-time multimedia data on web. For applying XML-based web service of process data in Intranet environment, real-time performance of communication services was evaluated to provide the system design criteria. XML schema for the data presentation was proposed and its communication performance was evaluated by simulation in terms of transmission delay due to increased message length and processing delay for transformation of raw data into defined format. For transformation of raw data into XML format, we proposed two structures: one is the scheme where transformation is done at an SCC(Supervisory Control Computer) after receiving real-time data from instruments. the other is the scheme where transformation is carried out at instruments before the data are transmitted to the SCC. Performances of two structures were evaluated on a testbed under various conditions such as six packet sizes and offered loads of 20%, 50% and 80%, respectively. Test results show that proposed schemes are applicable to the systems in Ethernet 100BaseT network if total message traffic is less than 7 Mbps.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.10 no.8
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• pp.1490-1494
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• 2006

Most network equipment is an embedded system designed to execute specific function. An embedded system is an electronic control system mixing hardware and software to execute only fixed function for the purpose of system, not confuter, performing diverse function for a wide use. Early embedded system executed only simple function, combining specific function with optimization, a micro size, and low power, but it has developed to meet complex and diverse system. The purpose of this study is to realize DHCP server based on embedded system. To achieve this, embedded Linux was ported in ez Bord-M01 mounted with Intel Strong ARM SA1110 processor, and ethernet-based network was constructed for network function. In this way, this study suggests embedded DHCP server where Window and Linux client hosts are dynamically configurated as network information by dynamically assigning network information in embedded board.