• Journal of Communications and Networks
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• v.4 no.3
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• pp.161-169
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• 2002

Ad hoc wireless networks involving large populations of scattered communication nodes will play a key role in the development of low power, high capacity, interactive, multimedia communication networks. Such networks must support arbitrary network connections and provide coverage anywhere and anytime. This paper partitions such arbitrarily connected network architectures into three distinct groups, identifies the associated dual network architectures and counts the number of network architectures assuming there exist N network nodes. Connectivity between network nodes is characterized as a random event. Defining the link availability P as the probability that two arbitrary network nodes in an ad hoc network are directly connected, the network connection probability $ \integral_n$(p) that any two network nodes will be directly or indirectly connected is derived. The network connection probability $ \integral_n$(p) is evaluated and graphically demonstrated as a function of p and N. It is shown that ad hoc wireless networks containing a large number of network nodes possesses the same network connectivity performance as does a fixed network, i.e., for p>0, $lim_{N\to\infty} Integral_n(p)$ = 1. Furthermore, by cooperating with fixed networks, the ad hoc network connection probability is used to derive the global network connection probability for hybrid networks. These probabilities serve to characterize network connectivity performance for users of wireless ad hoc and hybrid networks, e.g., IEEE 802.11, IEEE 802.15, IEEE 1394-95, ETSI BRAN HIPERLAN, Bluetooth, wireless ATM and the world wide web (WWW).

• Journal of Computing Science and Engineering
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• v.4 no.3
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• pp.225-239
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• 2010

This paper introduces a new approach to modeling relative distance among nodes under a variety of communication rates, due to node's mobility in Mobile Ad-hoc Networks (MANETs). When mobile nodes move to another location, the relative distance of communicating nodes will directly affect the data rate of transmission. The larger the distance between two communicating nodes is, the lower the rate that they can use for transferring data will be. The connection certainty of a link also changes because a node may move closer to or farther away out of the communication range of other nodes. Therefore, the stability of a route is related to connection entropy. Taking into account these issues, this paper proposes a new routing metric for MANETs. The new metric considers both link weight and route stability based on connection entropy. The problem of determining the best route is subsequently formulated as the minimization of an object function formed as a linear combination of the link weight and the connection uncertainty of that link. The simulation results show that the proposed routing metric improves end-to-end throughput and reduces the percentage of link breakages and route reparations.

• Journal of the Korea Society for Simulation
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• v.17 no.1
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• pp.9-16
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• 2008

The sink mobility can request frequent routing change in sensor networks. By active mobility a sink can gather needed information easily so that the network availability will be higher. However, instead static sink system, the connection between sensor nodes and a mobile sink can be changed continuously. That is, the rerouting should be implemented caused by the routing alteration. It is two connection setups for the mobile sink system: the connection from sink to sensor nodes and the connection from sensor nodes to sink. However, sensor nodes actually have many functional limitations. Hence, the low cost scheme will be needed for the connection setup from sensor nodes to the mobile sink. In this paper, we propose an agent scheme to the connection setup from sensor nodes to the mobile sink. The agent scheme provides the reliable setup scheme to the connection by using an agent sector.

• Journal of the Korea Society for Simulation
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• v.13 no.2
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• pp.53-63
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• 2004

In ad hoc networks, the link survivability is firstly considered if a routing between two mobile nodes takes place through wireless environments, because all of mobile nodes participating in a connection dynamically move to anywhere. Also, mobile nodes have multi-role to implement a communication without a static system supported by wired networks. Hence, it is difficult that all mobile nodes continuously provide a reliable connection when the nodes operate each role for the connection. Therefore, it is desired to maximize the lifetime of a route as long as possible for the reliable communication. In this paper, we propose a proactive link management scheme that can provide the continuous route supported by the link handover. It consider the wireless link quality and the power lifetime of a node so that the link handover is implemented for the link survivability without disconnecting the route on the communication.

• Convergence Security Journal
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• v.12 no.4
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• pp.91-96
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• 2012

MANET is developed technique fairly among many field of wireless network. Nodes which consist of MANET transmit data using multi-hop wireless connection. Caching scheme is technique which can improve data access capacity and availability of nodes. Previous studies were achieved about dynamic routing protocol to improve multi-hop connection of moving nodes. But management and maintenance of effective cache information because of movement of nodes is not easy. In this study, we proposed cluster-based caching scheme to manage connection by decreasing overhead and moving of nodes as moving node discovers cache of wish information. And HLP was used to maintain effective cache table in each cluster head. Efficiency of proposed technique in this study was confirmed by experiment.

• Steel and Composite Structures
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• v.36 no.5
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• pp.493-506
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• 2020

The load-slip relationship of the shear connection is an important parameter in design and analysis of composite structures. In this paper, a load-slip curve prediction method of the shear connection based on the artificial neural networks (ANNs) is proposed. The factors which are significantly related to the structural and deformation performance of the connection are selected, and the shear stiffness of shear connections and the transverse coordinate slip value of the load-slip curve are taken as the input parameters of the network. Load values corresponding to the slip values are used as the output parameter. A twolayer hidden layer network with 15 nodes and 10 nodes is designed. The test data of two different forms of shear connections, the stud shear connection and the perforated shear connection with flange heads, are collected from the previous literatures, and the data of six specimens are selected as the two prediction data sets, while the data of other specimens are used to train the neural networks. Two trained networks are used to predict the load-slip curves of their corresponding prediction data sets, and the ratio method is used to study the proximity between the prediction loads and the test loads. Results show that the load-slip curves predicted by the networks agree well with the test curves.

• Structural Engineering and Mechanics
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• v.43 no.3
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• pp.349-370
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• 2012

Variable-node finite element families, termed (4 + k + l + m + n)-node elements with an arbitrary number of nodes (k, l, m, and n) on each of their edges, are developed based on the generic point interpolation with special bases having slope discontinuities in two-dimensional domains. They retain the linear interpolation between any two neighboring nodes, and passes the standard patch test when subdomain-wise $2{\times}2$ Gauss integration is employed. Their shape functions are automatically generated on the master domain of elements although a certain number of nodes are inserted on their edges. The elements can provide a flexibility to resolve nonmatching mesh problems like mesh connection and adaptive mesh refinement. In the case of adaptive mesh refinement problem, so-called "1-irregular node rule" working as a constraint in performing mesh adaptation is relaxed by adopting the variable-node elements. Through several examples, we show the performance of the variable-node finite elements in terms of accuracy and efficiency.

• Journal of Korea Multimedia Society
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• v.21 no.6
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• pp.667-677
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• 2018

Since sensor networks consist of sensor nodes with limited energy resources, so efficient energy use of sensor nodes is very important in the design of sensor networks. Sensor nodes consume a lot of energy for data transmission. Clustering technique is used to efficiently use energy in data transmission. Recently, mobile sink techniques have been proposed to reduce the energy load concentrated on the cluster header near a sink node. The CMS(Cluster-based Mobile sink) technique minimizes the generation of control messages by creating a data transmission path while creating clusters, and supports the inter-cluster one-hop transmission. But, there is a case where there is no connectivity between neighbor clusters, it causes a problem of having a long hop data transmission path regardless of local distance. In this paper, we propose a SCBC(Strong connection balancing cluster) to support the path of the minimum number of hops. The proposed scheme minimizes the number of hops in the data transmission path and supports efficient use of energy in the cluster header. This also minimizes a number of hops in data transmission paths even when the sink moves and establishes a new path, and it supports the effect of extending the life cycle of the entire sensor network.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.6
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• pp.169-175
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• 2011

This paper addresses mobile IP router which communicate between nodes in Ad Hoc network as well as supply attachment to outer Internet. Ad Hoc network is one which exchanges information through cooperations among nodes without wire infrastructure, mobile IP router considers the network as one mobile unit, and supports Internet connection in mobile as well as fixed spaces. Therefore, this router can accommodate the routing of Ad Hoc network, and provide nodes in Ad Hoc network with Internet connection. So mobile IP router can provide Ad-Hoc terminals with the diverse wireless services, such as Internet connection service, routing, mobility, and so on.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.9 no.1
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• pp.58-64
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• 2005

The nodes of Ad-hoc network are made up of location registration for sending information and a great number of packet transmissions to maintain routing route among the nodes. under this environment, a huge number of traffics would be generated as mobility variable occurs more than in physical network. Hence, in this paper, focused on to study the relationship of nodes to analyze the extend of the traffic in order to control the traffics of the multi-hop in Ad-hoc.