• Journal of the Institute of Electronics Engineers of Korea TC
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• v.40 no.6
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• pp.205-212
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• 2003

Because a wireless ad hoc network does not have fixed infrastructure, a call admission control approach researched in a wireless network is not feasible to this network. In this paper, we propose call admission control scheme to support this problem and the burst handoff traffic due to group mobility in a wireless ad hoc network. This scheme is an adaptive guard channel scheme which adapt the number of guard channels in each MBS(mobile base station) according to the current estimate of the potential handoff call rate derived from the number of ongoing calls within the coverage area of an MBS that initiate group handoff in a wireless ad hoc network. Our simulation studies are performed for comparisons of the proposed scheme with the other channel allocation schemes. Simulation results show that the proposed scheme efficiently reduces handoff call blocking probability in wireless ad hoc networks.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.4
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• pp.324-332
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• 2011

Purpose: The purpose of this study was to compare the stress distribution of teeth and jaw on load by differentiating property of materials according to each layer of widely used mouthguard. Materials and methods: A Korean adult having normal cranium and mandible was selected to examine. A customized mouthguard was constructed by use of DRUFOMAT plate and DRUFOMAT-TE/-SQ of Dreve Co. according to Signature Mouthguard system. The cranium was scanned by means of computed tomography with 1mm interval. It was modeled with CANTIBio BIONIX/Body Builder program and simulated and interpreted using Alter HyperMesh program. The mouthguard was classified as follows according to the layers. (1) soft guard (Bioplast)(SG) (2) hard guard (Duran)(HG) (3) medium guard (Drufomat)(MG) (4) soft layer + hard layer (SG + HG) (5) hard layer + soft layer (HG + SG) (6) soft layer + hard layer + soft layer (SG + HG + SG) (7) hard layer + soft layer + hard layer (HG + SG + HG) The impact locations on mandible were gnathion, the center of inferior border, and the anterior edge of gonial angle. And the impact directions were oblique ($45^{\circ}$). The impact load was 800 N for 0.1 sec. The stress distribution was measured at maxillary teeth, TMJ and maxilla. The statistics were conducted using Repeated ANOVA and in case of difference, Duncan test was used as post analysis. Results: In teeth and maxilla, the mouthguard contacting soft layer of mandibular teeth presented lowest stress measure and, in contrast, in condyle, the mouthguard contacting hard layer of mandibular teeth presented lowest stress measure. Conclusion: For all impact directions, soft layer + hard layer + soft layer, the mouthguard with three layers which the hard layer is sandwiched between two soft layers, showed relatively even distribution of stress in impact.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.14 no.6
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• pp.189-197
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• 2014

This study analyzed the characteristics of multiple intelligence and the levels of academic adjustment for the department and the major among undergraduate students majoring in IT. Seventy freshmen majoring in IT at the department of M, H University participated in this study and the basic major subject required for the department was Computer Language: I-C Language. Eight intelligence areas less controversial in Gardner's multiple intelligence theory were used; academic adjustment was manipulatively defined as the degree of adjustment for the department and the major among undergraduate students; and pleasure, flow, familiarity and relevance to the major, academic achievement, and major satisfaction were selected as variables through literature review. The undergraduate students majoring in IT showed high levels of interpersonal intelligence and intrapersonal intelligence, with insignificant gender differences. Significant correlations were found between multiple intelligence and academic adjustment. In particular, while pleasure and flow in C programming were found to be at low levels in academic adjustment, the significant correlation between linguistic intelligence in multiple intelligence and flow in C language was a very interesting finding. While significant correlation was not found between multiple intelligence and academic achievement, students who were more highly aware of the relevance to the major and who were more familiar with C language showed higher academic achievement. Lastly, limitations of this study were discussed; on the basis of the results, suggestions were made about prescriptive strategies to improve academic achievement for undergraduate students majoring in IT.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.2
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• pp.157-168
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• 2010

Many athletes have been using occlusal stabilization appliances to improve their performance. Few studies have examined the benefits of such an appliance in golf. We determined the effect of such appliances on the masticatory muscle activities and driving distances of professional golf players. The appliances were customized for each player and adjusted using a computerized device. The electromyographic muscle activities and driving distances with and without the appliance were measured and compared using the K7 Analyzer and the GolfAchiever II assembly. A paired t-test was used for statistical analysis. The muscle activities of the temporo-frontal and masseter muscles with the appliance were significantly more stable than those without the appliance, and the driving distances with the appliance were significantly different from those without it. Although there were intra-individual differences, professional golf players with temporomandibular disorders showed a greater improvement in performance.