• Journal of Convergence Society for SMB
• /
• v.4 no.1
• /
• pp.7-15
• /
• 2014

In this paper, we propose an efficient routing protocol to achieve an optimal route searching process of the network lifetime by balancing power consumption per node. The proposed protocols aim at finding energy-efficient paths at low protocol power. In our protocol, each intermediate node keeps power level and branch number of child nodes and it transmits the data the nearest neighbor node. Our protocol may minimize the energy consumption at each node, thus prolong the lifetime of the system regardless of the location of the sink outside or inside the cluster. In the proposed protocol for inter-cluster communication, a cluster head chooses a relay node from its adjacent cluster heads according to the node's residual energy and its distance to the base station. Simulation results show that proposed protocol successfully balances the energy consumption over the network, and achieves a remarkable network lifetime improvement as highly as 7.5%.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.20 no.4
• /
• pp.1320-1332
• /
• 1996

In the present study, we consider modified 5-node equivalent solid element which has smallest degree of freedom among 2-dimensional solid elements accounting bending deformation as well as extensional and shear deformations, We shall investigate static and dynamic characteristics of this element, which is very effective in thin beam, thick beam, large displacement problems, beam of variable thickness, and asymmetrically stepped beam, etc., as well as relatively simple problems of beam. The degree of freedom of this element is 10, which is smaller than 18 of 9-node element, 16 of 8-node elemtns, 12 of modified 6-node element and Q6 element. Therefore, this element is expected to broaden the effective range of application of the solid elements in the bending problems further.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.46 no.4
• /
• pp.53-62
• /
• 2023

Effects-Based Operations (EBO) refers to a process for achieving strategic goals by focusing on effects rather than attrition-based destruction. For a successful implementation of EBO, identifying key nodes in an adversary network is crucial in the process of EBO. In this study, we suggest a network-based approach that combines network centrality and optimization to select the most influential nodes. First, we analyze the adversary's network structure to identify the node influence using degree and betweenness centrality. Degree centrality refers to the extent of direct links of a node to other nodes, and betweenness centrality refers to the extent to which a node lies between the paths connecting other nodes of a network together. Based on the centrality results, we then suggest an optimization model in which we minimize the sum of the main effects of the adversary by identifying the most influential nodes under the dynamic nature of the adversary network structure. Our results show that key node identification based on our optimization model outperforms simple centrality-based node identification in terms of decreasing the entire network value. We expect that these results can provide insight not only to military field for selecting key targets, but also to other multidisciplinary areas in identifying key nodes when they are interacting to each other in a network.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.18 no.11
• /
• pp.1726-1734
• /
• 1993

This paper propose a survivable communication network design process using node degree that augments the usual traffic flow and cost analyses with previously ignored topological survivability and computing time considerations. At first, decide a initial topology, and then measure a throughput of network. If the throughput is smaller than the required traffic, add edge to the optimum place by using minimum node degree and link distance. Otherwise, drop useless edge by using maximum node degree, link distance and link utilization. This process is repeated until throughput equals to the required traffics. This Process designs a survivable communication network with the minimized cost and computing time and usual traffic flow. The design proceses that minimized computing time are freely select initial topology and easily design a large network. And these results of algorithm are compared with the Kris and Pramod's in order to analyses the perfmance of the designed network.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38B no.6
• /
• pp.417-426
• /
• 2013

The Korea Internet AS-level topology was constructed using three data sources: Border Gateway Protocol (BGP) trace collector, Internet Routing Registry (IRR), and Internet Exchange Point (IXP). It has 685 nodes and 1,428 links. The Korea Internet AS-level topology is a small regional subgraph of the massive global one. We investigate how well the Korea Internet preserves the topological characteristics of the global one or how different they are. We carefully select several topology metrics that can analyze the characteristics of the Korea Internet AS-level topology. We also investigate how well Internet topology generators can represent the characteristics of the Korea Internet AS-level topology.

• East Asian mathematical journal
• /
• v.22 no.2
• /
• pp.163-170
• /
• 2006

In networking, it is essential to analyse the nodes along with their neighbours. The properties of fuzzy finite graphs are very much useful in obtaining solutions to many problems like traffic congestion problem. In this paper, free nodes and busy nodes are defined and the properties of nodes are examined at various levels of their degrees.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.38C no.1
• /
• pp.33-42
• /
• 2013

This paper presents a multihop range-free localization algorithm to estimate the physical location of a normal node with local connectivity information in anisotropic sensor networks. In the proposed algorithm, a normal node captures the detour degree of the shortest path connecting an anchor pair and itself by comparing the measured hop count and the expected hop count, and the node estimates the distances to the anchors based on the detour degree. The normal node repeats this procedure with all anchor combinations and pinpoints its location using the obtained distance estimates. The proposed algorithm requires fewer anchors and less communication overhead compared to existing range-free algorithms. We showed the superiority of the proposed algorithm over existing range-free algorithms through MATLA simulations.

• Journal of KIISE:Computer Systems and Theory
• /
• v.31 no.1_2
• /
• pp.78-85
• /
• 2004

Given a set S of n points in the plane, a minimum-diameter spanning tree(MDST) for the set might have a degree up to n-1. This might cause the degradation of the network performance because the node with high degree should handle much more requests than others relatively. Thus it is important to construct a spanning tree network with small degree and diameter. This paper presents an algorithm to construct a spanning tree for S satisfying the following four conditions: (1) the degree is controled as an input, (2) the tree diameter is no more than constant times the diameter of MDST, (3) the tree is monotone (even if arbitrary point is fixed as a root of the tree) in the sense that the Euclidean distance from the root to any node on the path to any leaf node is not decreasing, and (4) there are no crossings between edges of the tree. The monotone property will play a role as an aesthetic criterion in visualizing the tree in the plane.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.5
• /
• pp.3151-3154
• /
• 2013

Introduction: Colorectal cancers are in the top of the cancer-related causes of death in the world and lymph node metastasis is accepted as the primary prognostic factor. In this study, correlations of FGF19 staining pattern with local invasion and lymph node metastasis in a series of colorectal cancers were investigated. Methods: This studyincluded 81 colorectal cancer patients who underwent surgery in our hospital with no evidence of preoperative radiological distant metastasis. Routine pathological examination of the resection material was performed in order to identify vascular, perineural and serosal infiltration, regional lymph node metastasis and the degree of differentiation. Tumor tissue samples were stained with an immunohistochemistry method for FGF 19 evaluation and the staining pattern was statistically compared with the above mentioned characteristics of the tumors. Results: The patient population consisted of 47 females and 34 males with a median age of 70 years. In 40 patients regional lymph nodes were positive and 51%, 32% and 38% had serosal, perineural and vascular invasion. While 64 cases were moderately-differentiated, 11 cases were well-differentiated and 6 poorlydifferentiated, there was no association with FGF 19 staining, including intensity. Conclusion: No evidence of significant statistically correlation was found between FGF 19 staining pattern and serosal, perineural, vascular invasion, lymph node involvement and degree of differentiation.

• Journal of Plant Biology
• /
• v.36 no.1
• /
• pp.29-34
• /
• 1993

Observation was made on early ontogeny of vascular cambium in the cotyledonary node of Pinus koraiensis seedling in order to clarify the cambial ontogeny of the node which was hardly elongated. In transverse view, the derivatives by the early periclinal divisions at the outer region of the procambial strands differentiated to protophloem with establishing a certain degree of radial seriations. Later, some cells in the central region of the procambial strands begin divide periclinally, eventually the cells, differentiate gradually to the vascular cambium. In tangential view, early procambium is consisted of homogeneous short cells with transverse end walls which are tansformed into the long cells and short cells gradually. The long cells continue intrusive growth and the short cells repeat transverse division. Finally, the long and short cells differentiated to cambial fusiform initials and ray initials respectively. In tangential section, the differentiation pattern of cambial initials resembles that of the stem of Ginkgo biloba. But in transverse view, the characteristics in the origin of vascular cambium of the cotyledonary node resembles that of root. The vascular cambium in cotyledonary node is completed after eleven prophylls were formed.