• International Journal of Aeronautical and Space Sciences
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• v.16 no.4
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• pp.510-519
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• 2015

Concerning the issue of high-dimensions, hybrid uncertainties of randomness and intervals including implicit and highly nonlinear limit state function, reliability analysis based on the hybrid uncertainty reliability mode combining with back propagation neural network (HU-BP neural network) is proposed in this paper. Random variables and interval variables are as input layer of the neural network, after the training and approximation of the neural network, the response variables are obtained through the output layer. Reliability index is calculated by solving the optimization model of the most probable point (MPP) searching in the limit state band. Two numerical cases are used to demonstrate the method proposed in this paper, and finally the method is employed to solving an engineering problem of the aerospace friction plate. For this high nonlinear, small failure probability problem with interval variables, this method could achieve a good analysis result.

• ETRI Journal
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• v.44 no.6
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• pp.936-944
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• 2022

The mobile network allows redundant transmission via disjoint paths to support high-reliability communication (e.g., ultrareliable and low-latency communications [URLLC]). Although redundant transmission can improve communication reliability, it also increases network costs (e.g., traffic and control overhead). In this study, we propose a reliability-guaranteed multipath allocation algorithm (RG-MAA) that allocates appropriate paths by considering the path setup time and dynamicity of the reliability paths. We develop an optimization problem using a constrained Markov decision process (CMDP) to minimize network costs while ensuring the required communication reliability. The evaluation results show that RG-MAA can reduce network costs by up to 30% compared with the scheme that uses all possible paths while ensuring the required communication reliability.

• Journal of the Korea Institute of Building Construction
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• v.14 no.1
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• pp.102-109
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• 2014

The purpose of this study is to analyze collaborative relationship between members of a building construction organization. For the analysis of collaborative relationship, this researcher collected data by conducting a questionnaire survey with members of three large building construction organizations for apartment housing. The analyzed contents of collaborative relationship were the 'frequency of communication between organizational members' and their 'reliability'. According to the analysis of communication network, construction managers had low frequency of communication, whereas those responsible for each area, like construction deputy managers, had high frequency of communication. It indicates that middle managers are at the center of communication related to construction work in construction organizations. According to the analysis of reliability network, construction managers showed highest reliability, and employees at the top level in an organizational map also showed high reliability. Since they generally have a lot of experience, are some older of age, and assume responsibility for work, they are considered to receive reliability from other organizational members. This study proved that it was possible to numerically express reliability of organizational members, which is an abstract concept, and analyze it. Therefore, it is expected that the analysis result will highly be likely to be used in the area of construction management.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.60 no.3
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• pp.465-470
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• 2011

Recently fault currents are increasing in a network. It is caused by increase in electric demand and high penetration of distributed generation with renewable energy sources. Moreover, distribution network has become more and more complex as mesh network to improve the distribution system reliability and increase the flexibility and agility of network operation. Accordingly, the fault current will exceed capacity of circuit breakers soon and all the various rational solutions to solve this problem are taken into account. Under these circumstances, superconducting fault current limiter(SFCL) is a new alternative in the viewpoint of technical and economic aspects. This study presents operation processes for a resistive-type of SFCL, and it proposes reliability model for the SFCL. When a SFCL is installed into a network, the contribution of decreased fault currents to failure for distribution equipments can be quantified. As a result, it is expected that a SFCL makes the reliability of adjacent equipments on existing network improve and these changes are analyzed. We propose a methodology to evaluate the reliability in the distribution network where a SFCL is installed considering a reliability model for resistive-type of SFCL and reliability changes for adjacent equipments which are proposed in this paper.

• Journal of information and communication convergence engineering
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• v.9 no.6
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• pp.625-628
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• 2011

Dynamic sensor network(DSN) technology which is based on swarming flight type air node offers analyzed and acquired information on target data gathered by air nodes in rotation flight or 3 dimension array flight. Efficient operation of dynamic sensor network based on air node is possible when problems of processing time, data transmission reliability, power consumption and intermittent connectivity are solved. Delay tolerant network (DTN) can be a desirable alternative to solve those problems. DTN using store-and-forward message switching technology is a solution to intermittent network connectivity, long and variable delay time, asymmetric data rates, and high error rates. However, all processes are performed at the bundle layer, so high power consumption, long processing time, and repeated reliability technique occur. DSN based on swarming flight type air node need to adopt store-and-forward message switching technique of DTN, the cancelation scheme of repeated reliability technique, fast processing time with simplified layer composition.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.28B no.5
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• pp.369-381
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• 1991

In this paper, design algorithms for SMP(Single Mated Pair) and MMP (Multipli Mated Pair) structure of CCS (Common Channel Signaling) network are proposed through the study of the structure of CCS network. High reliability and fast messagy transfer time are the most important requirements for the CCS network. Based on it, three parameters such as monotraffic, reliability (maximum isolated SP(Signalling Point) number when any two STP(Signalling Transfer Points) fail and total network cost are defined. And the proposed algorithms different from preexisted algorithm that minimizes total network cost, maximize monotraffic with two constraints, reliability and total network cost. Comparing the experimental results of the proposed algorithms with those of the preexisted algorithm that minimizes total network cost, shows that the proposed algorithms produce a more reliable topology that has more monotraffic and a little higher total network cost. Additionaly, with the results of the proposed algorithms, SMP and MMP structures are compared.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.28 no.6
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• pp.587-594
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• 2010

This paper describe the optimal design of geodetic network by analytical technique based on the quality criteria of network. We described an example of geodetic network design taking into account the precision, reliability and robustness that are the main criteria of network design. The main goal of this paper is to evaluate the criteria to design the geodetic network coinciding with the criteria of high precision(error ellipse, 2DRMS, CEP), reliability(internal and external reliability) and robustness(maximum shear strain, principal strain, dilatation). The network design parameters computed in this study show that precision and reliability has not much improved by about 2% and 3%, respectively, than the observed network, while robustness has much improved by about 3, 100%. It also shown that maximum errors of precision, reliability and robustness were reduced by 5%, 7% and 16,957%, respectively.

• Journal of Electrical Engineering and Technology
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• v.7 no.4
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• pp.486-492
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• 2012

This paper presents a novel objective function for distribution system reconfiguration for reliability enhancement. When islanding operations of distributed generators is prohibited, faults in the feeder interrupt the operation of distributed generators. For this reason, we include the customer interruption cost as well as the distributed generator interruption cost in the objective function in the network reconfiguration algorithm. The network reconfiguration in which genetic algorithms are used is implemented by MATLAB. The effect of the proposed objective function in the network reconfiguration is analyzed and compared with existing objective functions through case studies. The network reconfiguration considering the proposed objective function is suitable for a distribution system that has a high penetration of distributed generators.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.12
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• pp.1241-1248
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• 2006

In high reliability systems for industrial network such as railway signal system, fieldbus protocols have been known to satisfy the real-time and fault tolerant requirements. But, the application of fieldbus has been limited due to the high cost of hardware and software, and the difficulty in interfacing with multi-vendor products. Therefore, as an alternative to fieldbus, the computer network technology, especially Ethernet(IEEE 802.3), is being adapted to the industrial network. In this paper, we propose a switched Ethernet based railway signal system because of its very promising prospect for industrial application due to the elimination of uncertainties in the network operation. In addition, we propose the redundancy architecture for the reliability of network components. More specifically, this paper presents an analytical performance evaluation of switched Ethernet for railway signal system, and shows experimental evaluation of redundancy architecture.

• Journal of Internet Computing and Services
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• v.4 no.6
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• pp.25-31
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• 2003

Multistage Interconnection networks (MIN) for the high performance computing and communications must be efficient and reliable. While a number of fault tolerance schemes have been developed, some of them are not efficient enough with respect to all evaluation measures or overheads of others are too significant. In this paper we develop a new efficient fault tolerant MIN which displays high reliability and fault tolerance capability using a simple structure. Structure and reliabilities of Enhanced Cube Network are evaluated and compared with previous designs to show the effectiveness of new design.