• Journal of the Korean Professional Engineers Association
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• v.27 no.6
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• pp.72-84
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• 1994

This is about an environmental study of groundwater interference by hydrodynamic dispersion between the well A and well C in Dongsam-dong, the Yeongdo Island, Pusan, Korea. The groundwater in the study wells come from the fracture zones deeply seated in welded lapilli rhyodacitic tuff of the Late Cretaceous Yucheon Group. The boring depth at the well A is 190 meters, and the optimal pumping rate of the well A is about 100 cubic meters per day therein. The fractured aquifers in impermeable welded tuff show the conjugate fracturing type and are of anisotropic. The aquifers along two fracture zones in the well A are 80 and 100 meters in depth, respectively. It is not suggested that those fractured aquifers are simply connected between the well A and C. The sea level fluctuation by ebb and high tides in a day is not effective to the groundwater table in the well A. The pumping for 15 days at the well A doesn't give rise to any changes of the groundwater levels in the neighbor well C. The radius of influence of the well A is measured as less than 200 meters. The measuring electric conductivity for the test of salt tracer doesn't testify any relationship between the well A and the well C. There is the main difference between the well A and the well C on the basis of the water analysis of those wells. the well A is located in the high content zone of salt much over the standard value for drinking, whereas the other wells B. C. D are in the low content area of salt below the standard value. It is elucidated for the high content zone of salt in Yeongdo around the well A to have been uplifted over 20 meters.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2012.10a
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• pp.31-34
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• 2012

In MANET, frequent movement of nodes causes the dynamic network topology changes. Therefore the routing protocol, which is very stable to effectively respond the changes of the network changes, is required. Moreover, the existing cluster-based routing protocol, that is the hybrid approach, has routing delay due to the re-electing of the cluster header. In addition, the routing table of CBRP has all only one hop distant neighbor nodes. PCBRP, proposed in this paper, ties two clusters in one pair of clusters to make longer radius. Then the pair of the cluster headers manages and operates corresponding member nodes. When they route nodes in the paired cluster internally, PCBRP reduces the delay by requesting a route. Therefore PCBRP shows improved total delay of the network and improved performance of packet transmitting rate.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.8A
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• pp.581-590
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• 2003

This paper proposes the routing path selection mechanism for source routing-based PtMP (Point-to-Multipoint) call in ATM switching system. Especially, it suggests PtMP routing path selection method that can share the maximum resource prior to the optimal path selection, guarantee the reduction of path calculation time and cycle prevention. The searching for the nearest branch point from destination node to make the maximum share of resource is the purpose of this algorithm. Therefore among neighbor nodes from destination node by back-tracking, this algorithm fixes the node crossing first the node on existing path having the same Call ID as branch node, constructs the optimal PtMP routing path. The optimal node to be selected by back-tracking is selected by the use of Dijkstra algorithm. That is to say, PtMP routing path selection performs the step of cross node selection among neighboring nodes by back-tracking and the step of optimal node selection(optimal path calculation) among neighboring nodes by back-tracking. This technique reduces the process of search of routing information table for path selection and path calculation, also solves the cycle prevention easily during path establishment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.3A
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• pp.219-224
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• 2008

In the c-DSDV routing protocol proposed to improve the scalability of DSDV, clusterheads manage a routing table that has only clusterheads as potential destinations and flood update request message to its neighbor clusterheads periodically or at the time of topology change. Accordingly, the convergence range of topology change by a single update request message was expanded nine times as wide as that of DSDV, increasing routing correctness; however, c-DSDV suffers from the congestion of clusterheads since data packets always go through clusterheads of the clusters on the routing path. To improve this problem, we propose an adaptive routing scheme that judges if detouring clusterhead is possible on the fly while packets are forwarded. As a result, a routing path length is shortened and an end-to-end delay is improved by the reduced queue length. It shows that the end-to-end delay is reduced by almost 40% through simulation.

• Journal of Korea Multimedia Society
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• v.16 no.1
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• pp.56-66
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• 2013

In MANET, the frequent movement of nodes causes the dynamic network topology changes. Therefore, it is required that the routing protocol should be very stable to effectively respond the changes of the network changes. Moreover, the existing cluster-based routing protocol, that is the hybrid approach, has routing delay due to the re-electing of the cluster header. In addition, the routing table of CBRP has all only one hop distant neighbor nodes. PCBRP, proposed in this paper, ties two clusters in one paired cluster to make longer radius. Then the headers of the paired cluster manage and operate corresponding member nodes. In the current CBRP, when the cluster header leaves out the cluster, the delay, due to the re-electing a header, should be occurred. However, in PCBRP, another cluster header of the paired cluster plays the role instead of the left cluster header. This method reduces the routing delay. Concurrently, PCBRP reduces the delay when they route nodes in the paired cluster internally.

• KIPS Transactions on Computer and Communication Systems
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• v.8 no.3
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• pp.73-78
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• 2019

Due to frequent topology changes in wireless networks, inter-node link disconnection and path re-establishment occur, causing problems such as overloading control messages in the network. In this paper, to solve the problems such as link disconnection and control message overload, we perform path setup in three steps of the neighbor node discovery process, the route discovery process, and the route management process in the wireless network environment. The link stability value is calculated using the information of the routing table. Then, when the zone master monitors the calculated link value and becomes less than the threshold value, it predicts the link disconnection and performs the path reset to the corresponding transmitting and receiving node. The proposed scheme shows a performance improvement over the existing OLSR protocol in terms of data throughput, average path setup time, and data throughput depending on the speed of the mobile node as the number of mobile nodes changes.

• Journal of Preventive Medicine and Public Health
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• v.33 no.2
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• pp.215-225
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• 2000

Objective : The purpose of this study was to examine the therapeutic compliance and its related factors in the rural hypertensives. Method : A questionnaire survey and blood pressure measurement were performed to 3,876 residents of a rural area, and 660 hypertensives were selected as subjects of study. The study employed a hypothetical model which was composed of constructs from the health belief model and KAP model. The analysis techniques employed included contingency table analysis and structural equation modeling. Result : The proportion of those who were compliant to the treatment of hypertension was 44.2% of subjects. As the result of structural equation modeling, when patients had more favorable attitude toward treatment, higher perceived benefit, or lower perceived barriers to treatment, the therapeutic compliance was significantly higher(T>2.0). When patients had more knowledge about hypertension, or higher perceived severity of hypertension, the attitude toward the treatment of hypertension was more favorable significantly(T>2.0). And when patients had the support for treatment from family or neighbor, the attitude toward treatment was more favorable(T>2.0). When patients had experience of health education, they had more knowledge, higher perceived susceptibility of complication, perceived severity for hypertension, and perceived benefit of treatment, compare to patients without health education(T>2.0). Conclusion : In consideration of above findings, in order to improve the therapeutic compliance in the rural hypertensives, it would be necessary to change attitude, perception, knowledge about hypertension and its treatment, by various methods such as effective health education and programs for maintaining the supportive environment for hypertension treatment.