• Proceedings of the KIPE Conference
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• 1998.10a
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• pp.197-200
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• 1998

Three switched-capacitor(SC) networks are presented including series-parallel capacitor set, reversed-switched-capacitor network and push-pull switched-capacitor network, the performances of which are discussed. Combining the SC networks with traditional DC-DC converters, we form several new topologies. Experiment and analyzed results show that the behavior of a DC-DC converter with large voltage ratio can be improved. A wider voltage conversion range is also obtained.

• The KIPS Transactions:PartC
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• v.11C no.1
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• pp.99-108
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• 2004

In this paper, the performance of switched ethernet networks with different topologies as an industrial control networks is analyzed. The switched ethernet eliminated data collisions on the network and can be used to transmit real-time data. While the amount of data on the network is small compared to the computer networks, the industrial control networks require the real-time data delivery. In this paper, we analyze and compare the network performance of switched ethernet networks with linear and tree topologies whether they satisfy the real-time data delivery requirement needed to be used as the industrial control networks.

• Journal of the Korea Society of Computer and Information
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• v.1 no.1
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• pp.25-36
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• 1996

We have analyzed the reliability of failure models In grid topology circuit switched networks. These models are grid topology circuit_ switched networks. and each node transmits packets to object node using flooding search routing method. We hypothesized that the failure of each link Is Independent. We have analyzed for the performance estimation of failure models It using joint probability method to the reliability of a small grid topology circuit switched network. and compared analytic output with simulated output. Also. We have evaluated the reliability of networks using call blocking Probability occurred in circuit switched networks.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.31B no.5
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• pp.123-133
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• 1994

This paper presents an output arbitrator for input buffering ATM (Asynchronous Transfer Mode) switches using neural networks. To avoid blocking in ATM switches with blocking characteristics, it is required to buffer ATM cells in input buffer and to schedule them. The N$\times$N request matrix is divided into N/16 submatrices in order to get rid of internal blocking systematically in scheduling phase. The submatrices are grouped into N/4 groups, and the cells in each group are switched alternatively. As the window size of input buffer is increases, the number of input cells switched in a time slot approaches to N. The selection of nonblocking cells to be switched is done by neural network modules. N/4 neural network modules are operated simultaneously. Fast selection can be achieved by massive parallelism of neural networks. The neural networks have 4N neurons and 14N connection. The proposed method is implemented in C language, and the simulation result confirms the feasibility of this method.

• 한국정보통신설비학회:학술대회논문집
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• 2009.08a
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• pp.91-96
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• 2009

In Public Switched Telephone Networks(PSTN) number portability is implemented by utilizing Intelligent Network(IN) functions for number mapping. And voice over IP(VoIP) and IP Multimedia Subsystem(IMS) networks can deploy number portability by using E.164 Number Mapping(ENUM). This paper discuss the possibility of using E.164 Number Mapping(ENUM) for number portability in voice over IP/IP Multimedia Subsystem and Public Switched Telephone Networks, eliminating the need for Number Portability Database(NPDB) for number portability routing data in Public Switched Telephone Networks.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.8
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• pp.1-10
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• 1995

We have analyzed the reliability of failure models in circuit-switched networks. These models are grid topology circuit-switched networks, and each node transmits a packet to a destination node using a Flooding routing method. We have assumed that the failure of each link and node is independent. We have considered two method to analyze reliability in these models : The Karnaugh Map method and joint probability method. In this two method, we have analyzed the reliability in a small grid topology circuit switched network by a joint probability method, and comared analytic results with simulated ones. For a large grid enormous. So, we have evaluated the reliability of the network by computer simulation techniques. As results, we have found that the analytic results are very close to simulated ones in a small grid topology circuit switched network. And, we have found that network reliability decreases exponentially, according to increment of link or node failure, and network reliability is almost linearly decreased according to increment of the number of links, by which call has passed. Finally, we have found an interesting result that nodes in a center of the network are superior to the other nodes from the reliability point of view.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.31A no.12
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• pp.1-8
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• 1994

In this paper, we hve compare the performance of DAR(Dynamic Adaptive Routing) with that of FSR(Flooding Search Routing) to select an adequate routing protocol in circuit-switched networs. As a performance factor, we have considered call setup time, which is the key factor of performance evaluation in circuit switched networks. We have evaluated the performance of two methods in grid topology circuit-switched networks using a commn channel signaling scheme, as application examples. As results, FSR method shows better performance than DAR method under light traffic load, when the number of links by which call has passed increases, but DAR method represents better performance than FSR method under heavy traffic load or large networks because of redundant packets.

• Journal of Institute of Control, Robotics and Systems
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• v.6 no.8
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• pp.666-671
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• 2000

With the current advances in optical WDM (Wavelength Division Multiplexing) networking technologies and the increasing demand for network bandwidth the Next Generation Internet is expected to be a network that runs IP(Internet Protocol) directly over WDM-based optical networks. The network control architecture for the IP over WDM networks is different from that of traditional Internet since the underlying WDM devices have more constraints than electronic IP routers such as the lack of optical buffers and wavelength continuity property etc. In this paper we introduce several architectural models for implementing IP over WDM networks and propose an integrated network control framework for the IP over WDM networks. This framework leverages the traffic engineering control architecture for the MPLS (Multi-Protocol Label Switching) networks and is mainly developed for the IP over packet-switched WDM networks. We also report several preliminary simulation results of contention resolution schemes in the packet-switched WDM networks.

• ETRI Journal
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• v.31 no.2
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• pp.111-120
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• 2009

Network-on-chip (NoC) architecture provides a highper-formance communication infrastructure for system-on-chip designs. Circuit-switched networks guarantee transmission latency and throughput; hence, they are suitable for NoC architecture with real-time traffic. In this paper, we propose an efficient integrated scheme which automatically maps application tasks onto NoC tiles, establishes communication circuits, and allocates a proper bandwidth for each circuit. Simulation results show that the average waiting times of packets in a switch in $6{\times}6$6, $8{\times}8$, and $10{\times}10$ mesh NoC networks are 0.59, 0.62, and 0.61, respectively. The latency of circuits is significantly decreased. Furthermore, the buffer of a switch in NoC only needs to accommodate the data of one time slot. The cost of the switch in the circuit-switched network can be reduced using our scheme. Our design provides an effective solution for a critical step in NoC design.

• Journal of National Security and Military Science
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• s.1
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• pp.345-360
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• 2003

To build an information oriented armed forces, the Korean military telecommunication networks adopt TCP/IP standard communication infrastructures based on ATM packet switched networks. Utilizing this network infrastructure, the Korean armed forces also applies to the areas of battleship management for efficient operation command controls and resource management for efficient resource allocations. In this military communication networks, it is essential to determine the least cost network topology under equal performance and reliability constraints. Basically, this type of communication network design problem is known in the literature as an NP Hard problem. As the number of network node increases, it is very hard to obtain an optimal solution in polynomial time. Therefore, it is reasonable to use a heuristic algorithm which provides a good solution with minimal computational efforts. In this study, we developed a simulated annealing based heuristic algorithm which can be utilized for the design of military communication networks. The developed algorithm provides a good packet switched network topology which satisfies a given set of performance and reliability constraints with reasonable computation times.