• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.1B
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• pp.56-61
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• 2000

The maximum number of nodes in WDM self healing ring network in limited by several factors including network architecture and ASE noise due to EDFAs at each optical ADM node. In this paper, the maximum node numbers for several protection architectures and bit rates limited by ASE are calculated and compared with the number limited by wavelength numbers. Appropriate design rules can be deduced from these results.

• Structural Engineering and Mechanics
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• v.16 no.4
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• pp.479-492
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• 2003

Non-conforming membrane elements which have variable number of mid-side nodes with drilling degrees of freedom and which is designated as NMDx have been presented in this paper. The non-conforming elements with variable number of mid-side nodes can be efficiently used in the local mesh refinement for the in-plane structures. To guarantee the developed elements always pass the patch test, the direct modification method is incorporated into the element formulation. Detailed numerical tests in this study show the validity of the variable node NC elements developed in this study and a wide applicability of these elements to practical problems.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.10a
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• pp.487-494
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• 2003

Recently it is used seismic analysis like single mode spectrum analysis, multi mode spectrum analysis and time history analysis in Korea. Because bridges are not special form of them but regular and simple form of them in our country, we must develope seismic analysis program of bridge based on single nude spectrum analysis. The program developed by this study reduces a Quantity and a time of calculation compared to SAP90 and gives accurate answers without errors. In the case of commercial program if we look for seismic load(P/sub e/(x)), we must increase the number of node and the larger the number of node the more a quantity and a time of calculation. But this program is exactly solved with basic node compared to commercial program.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.25 no.8A
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• pp.1247-1253
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• 2000

To fully utilize the capabilities of a SONET/ADM network, traffic grooming is needed to multiplex a number of lower-rate traffic streams into a higher-rate stream, and vice versa. Although the capacity of a SONET ring network can be upgraded by operating it over multiple wavelengths, the corresponding network design may be costly if it employs a large number of ADMs. A cost-effective design attempts to minimize the total number of ADMs used in the network while carrying the offered traffic. We introduce and evaluate the performance characteristics of a new traffic-grooming approach for WDM ring networks, called multihop. The multihop implementation places an ADM at each node based on the requested traffic in the traffic-demand matrix then, it tries to groom the wavelengths which can be groomed. We select one of the nodes to be the "hub" node which has an ADM for each wavelength. The hub node, therefore, can "bridge" traffic between all of the wavelengths. The algorithm is specified and illustrated by a simple example. Our results demonstrate that it is beneficial to use a single-hop approach, but for a large grooming ratio and node number, we advocate the use of the multihop approach.e multihop approach.

• Journal of Plant Biotechnology
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• v.34 no.2
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• pp.161-166
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• 2007

In vitro shoot regeneration and multiple shoot induction has been obtained from the stolen node explants in Eremochloa ophiuroides (Munro) Hack. The highest number of shoots ($10.66{\pm}0.21$) was observed from initial explants after one month culture duration on Murashige and Skoog (MS) medium containing 6-benzyladenine (BA: 0.5 mg/l). First generation shoot was excised and sub-cultured on the same fresh media for further multiplication of shoots. An enhanced number of second round shoots ($15.33{\pm}0.21$) was obtained compared to the initial culture media containing BA (0.5 mg/l). The number of shoots/stolon node was higher among all the concentrations of BA than kinetin (KN). In vitro regenerated shoots were successfully rooted in the phytohormone free MS medium. Plantlets generated with roots were transferred to pots containing compound mixture of soil and kept in green house conditions. Acclimatized plants showed 100% survival rate with normal morphology in green house conditions. The present study demonstrates the effect of explant and different plant growth regulators towards in vitro response in E. ophiuroides. Moreover, the study reveals the effect of cytokinin on induction of shoot number per stolen node explant in E. ophiuroides.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2016.10a
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• pp.256-259
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• 2016

The growth of mobile devices in Internet of Things (IoT) leads to a number of intelligent buildings related IoT applications. For instance, home automation controlling system uses client system such web apps on smartphone or web service to access the home server by sending control commands. The home server receives the command, then controls for instance the light system. The gateway based RESTful technology responsible for handling clients' requests attests an internet latency in case a large number of clients' requests submit toward the gateway increases. In this paper, we propose the design tasks of the IoT gateway for handling concurrency events. In the procedure of designing tasks, concurrency is best understood by employing multiple levels of abstraction. The way that is eminently to accomplish concurrency is to build an object-oriented environment with support for messages passing between concurrent objects. We also investigate the performance of event-driven architecture for building IoT gateway using node.js on one side and communication protocol based message-oriented middleware known as XMPP to handle communications of intelligent building control devices connected to the gateway through a centralized hub. The Node.JS is 40% faster than the traditional web server side features thread-based approach. The use of Node.js server-side handles a large number of clients' requests, then therefore, reduces delay in performing predefined actions automatically in intelligent building IoT environment.

• Structural Engineering and Mechanics
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• v.14 no.6
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• pp.699-712
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• 2002

In this paper, a new quadrilateral 5-node non-conforming membrane element with drilling degrees of freedom is presented. The main advantage of these elements is the relatively small number of integration points to evaluate a stiffness matrix comparing to the existing transition membrane elements (CLM elements). Moreover, the presented elements pass the patch test by virtue of the Direct Modification Method incorporated into the element formulation. The presented 5-node elements are proved to be very efficient when used in the local mesh refinement for the in-plane structures which have stress concentrations. And some numerical studies also show the good performance of the new element developed in this study.

• Journal of information and communication convergence engineering
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• v.9 no.6
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• pp.676-682
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• 2011

Sybil attack can disrupt proper operations of wireless sensor network by forging its sensor node to multiple identities. To protect the sensor network from such an attack, a number of countermeasure methods based on RSSI (Received Signal Strength Indicator) and LQI (Link Quality Indicator) have been proposed. However, previous works on the Sybil attack detection do not consider the fact that Sybil nodes can change their RSSI and LQI strength for their malicious purposes. In this paper, we present a Sybil attack detection method based on a transmission power range. Our proposed method initially measures range of RSSI and LQI from sensor nodes, and then set the minimum, maximum and average RSSI and LQI strength value. After initialization, monitoring nodes request that each sensor node transmits data with different transmission power strengths. If the value measured by monitoring node is out of the range in transmission power strengths, the node is considered as a malicious node.

• Journal of Korea Multimedia Society
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• v.18 no.9
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• pp.1083-1090
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• 2015

A generalized recursive circulant network(GR) is widely used in the design and implementation of local area networks and parallel processing architectures. In this paper, we investigate the routing of a message on this network, that is a key to the performance of this network. We would like to transmit maximum number of packets from a source node to a destination node simultaneously along paths on this network, where the i^th packet traverses along the i^th path. In order for all packets to arrive at the destination node securely, the i^th path must be node-disjoint from all other paths. For construction of these paths, employing the Hamiltonian Circuit Latin Square(HCLS), a special class of (n x n) matrices, we present O(n²) parallel routing algorithm on generalized recursive circulant networks.

• Journal of Korea Society of Digital Industry and Information Management
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• v.10 no.2
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• pp.47-59
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• 2014

In this paper, I propose a new energy efficient clustering scheme to prolong the network lifetime by reducing energy consumption at the sensor node. It is possible that a node determines whether to participate in clustering with certain probability based on local density. This scheme is useful under the environment that sensor nodes are deployed unevenly within the sensing area. By adjusting the probability of participating in clustering dynamically with local density of nodes, the energy consumption of the network is reduced. So, the lifetime of the network is extended. In the region where nodes are densely deployed, it is possible to reduce the energy consumption of the network by limiting the number of node which is participated in clustering with probability which can be adjusted dynamically based on local density of the node. Through computer simulation, it is verified that the proposed scheme is more energy efficient than LEACH protocol under the environment where node are densely located in a specific area.