• Convergence Security Journal
• /
• v.8 no.3
• /
• pp.65-71
• /
• 2008

Network Flow has been playing important role in the modern industrial society. No matter what people or company run the network, both of them can't avoid circulating goods among the many branches. But in practical situations, not only the price rising in network increase the transportation costs, but the huge traffic flow volumes increase the transportation costs. Given to such a network environment, how to flow goods in the network is very important. In this paper, the MAX-Flow algorithm will be applied to network flow in order to maximize the network flow volumes. As far as the functions of network are correctly provided, the optimized network system always can make the flow process efficiently.

• Journal of the Korean Geographical Society
• /
• v.44 no.2
• /
• pp.187-205
• /
• 2009

Failures on network components of a public transportation system can give rise to the severe degradation of entire system functionality. This paper aims at exploring how potential failures can affect the system flows and reliability of subway network systems in Metropolitan Seoul. To evaluate the range of impacts of disruptions, this research employs a probabilistic approach, network reliability. Network reliability measures the network resiliency and probability of flow loss under a variety of simulated disruptions of critical network components, transfer stations in subway system. By identifying the best and worst scenarios associated with geographical impact, as well as evaluating the criticality of transfer stations, this research presents some insights for protecting current subways systems.

• Journal of Information Processing Systems
• /
• v.9 no.2
• /
• pp.301-314
• /
• 2013

In a parallel processing system, Multi-stage Interconnection Networks (MINs) play a vital role in making the network reliable and cost effective. The MIN is an important piece of architecture for a multiprocessor system, and it has a good impact in the field of communication. Optical Multi-stage Interconnection Networks (OMINs) are the advanced version of MINs. The main problem with OMINs is crosstalk. This paper, presents the (1) Destination Based Modified Omega Network (DBMON) and the (2) Destination Based Scheduling Algorithm (DBSA). DBSA does the scheduling for a source and their corresponding destination address for messages transmission and these scheduled addresses are passed through DBMON. Furthermore, the performance of DBMON is compared with the Crosstalk-Free Modified Omega Network (CFMON). CFMON also minimizes the crosstalk in a minimum number of passes. Results show that DBMON is better than CFMON in terms of the average number of passes and execution time. DBSA can transmit all the messages in only two passes from any source to any destination, through DBMON and without crosstalk. This network is the modified form of the original omega network. Crosstalk minimization is the main objective of the proposed algorithm and proposed network.

• Convergence Security Journal
• /
• v.4 no.3
• /
• pp.1-8
• /
• 2004

Large distributed systems such as computational and data grids require that a substantial amount of monitoring data be collected for various tasks such as fault detection, performance analysis, performance tuning, performance prediction, security analysis and scheduling. to cope with this problem, they are needed network monitoring architecture which can collect various network characteristic and analyze network security state. In this paper, we suggest network performance and security analysis system based on network monitoring. The System suggest that users can see distance network state with tuning network parameters.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.10 no.8
• /
• pp.3701-3727
• /
• 2016

Recently Service Function Chaining (SFC) is promising to innovate the network service mode in modern networks. However, a feasible implementation of SFC is still difficult due to the need to achieve functional equivalence with traditional modes without sacrificing performance or increasing network complexity. In this paper, we present a configurable network service chaining (CNSC) mechanism to provide services for network traffics in a flexible and optimal way. Firstly, we formulate the problem of network service chaining and design an effective service chain construction framework based on integrating software-defined networking (SDN) with network functions virtualization (NFV). Then, we model the service path computation problem as an integer liner optimization problem and propose an algorithm named SPCM to cooperatively combine service function instances with a network utility maximum policy. In the procedure of SPCM, we achieve the service node mapping by defining a service capacity matrix for substrate nodes, and work out the optimal link mapping policies with segment routing. Finally, the simulation results indicate that the average request acceptance ratio and resources utilization ratio can reach above 85% and 75% by our SPCM algorithm, respectively. Upon the prototype system, it is demonstrated that CNSC outperforms other approaches and can provide flexible and scalable network services.

• Asian Journal of Innovation and Policy
• /
• v.6 no.1
• /
• pp.85-93
• /
• 2017

This paper focuses on the relationship between the characteristics of network and the productivity of scientists, which is rarely examined in previous studies. Utilizing a unique dataset from the Korean Citation Index (KCI), we examine the overall characteristics of the research network (e.g. distribution of nodes, density and mean distance), and analyze whether the network centrality is related to the scientific productivity. According to the results, firstly we have found that the collaborative research network of the Korean academics in the field of statistics and computer science is a scale-free network. Secondly, these research networks show a disciplinary difference. The network of statisticians is denser than that of computer scientists. In addition, computer scientists are located in a fragmented network compared to statisticians. Thirdly, with regard to the relationship between the researchers' network position and scientific productivity, a significant relation and their disciplinary difference have been observed. In particular, the degree centrality is the strongest predictor for the scientists' productivity. Based on these findings, some policy implications are put forward.

• Journal of the Korea Society of Computer and Information
• /
• v.10 no.6 s.38
• /
• pp.253-260
• /
• 2005

Active networks not only allows the network nodes, switches or routers. to perform routing and forwarding but so allows their users inject customized programs into the nodes of the network or the packets. that may modify, store or redirect the user data flowing through the network. In this paper, we proposed a new network management system built using active network technology, that can solve problems inherent in most of existing legacy centralized network management systems. The main contribution is to present the Smart Router model that can reduce traffics due to managing networks by way of making control packets into simplified patterns. The disadvantages of the centralized network management are presented and the current solution for distributed network management are discussed. The performance improvements that our architecture offers are showed through a service example experiment.

• Korean Journal of Health Education and Promotion
• /
• v.29 no.1
• /
• pp.1-11
• /
• 2012

Objectives: The nurse visiting health service named Customized Visiting Health Care Program(CVHCP) requires the service innovations incorporating community support into a local service network. The purpose of this study was to assess the community network in CVHCP and inform improvement in this network. Methods: We used Social Network Analysis(SNA) in one CVHCP at H city. Network links were generated by self-administered questionnaires by the 14 community resource centers who quantified their links to all other 25 agents on the list. Links were analyzed by a dichotomous scale for any experience of collaboration and a scored scale of 0 to 3 for level of collaboration using UCINET v6. Results: A list of 14 agents was generated, and local network was dominated by the Public Health Center and a local welfare center named Unlimited Care Center(UCC). According to centrality score, UCC was the most prominent agent, and Public Health Center was the most influential agent, being a link in the pathway flow between other agents for 9.5% of contribution. CVHCP scored lower rank of prominent with 30.8% of other agents reported referring to it. Conclusions: Social network analysis provides a useful network description for informing and evaluation service network improvement in maximizing its service for the CVHCP.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.7 no.4
• /
• pp.678-683
• /
• 2003

This study presents a result of performance with the design of network topology for voice and data integration under computer network. This network is consisted of FastEthernet, other LANs and ATM WAN(wide area network), and performance evaluation of delay in a PBX+IP network, delay in a VoIP network and delay in a IP+ATM network will be shown. We use parameters including network bandwidth, number of packet, routing protocol(IGRP, OSPF). We simulate integrated of voice and data used PBX. we will study further about the case of integrated of voice and data environments using PBX. and, evaluate IP+ATM WAN average measured network delay and average delay of VoIP network.

• Proceedings of the KIEE Conference
• /
• 2003.11b
• /
• pp.171-174
• /
• 2003

In this paper, a Learning module for a reconfigurable neural network processor(ERNIE) was proposed for an On-chip learning. The existing reconfigurable neural network processor(ERNIE) has a much better performance than the software program but it doesn't support On-chip learning function. A learning module which is based on Back Propagation algorithm was designed for a help of this weak point. A pipeline structure let the learning module be able to update the weights rapidly and continuously. It was tested with five types of alphabet font to evaluate learning module. It compared with C programed neural network model on PC in calculation speed and correctness of recognition. As a result of this experiment, it can be found that the neural network processor(ERNIE) with learning module decrease the neural network training time efficiently at the same recognition rate compared with software computing based neural network model. This On-chip learning module showed that the reconfigurable neural network processor(ERNIE) could be a evolvable neural network processor which can fine the optimal configuration of network by itself.