• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.6
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• pp.1063-1079
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• 2010

Vehicle ad hoc networks (VANET) are one of the most important technologies to provide various ITS services. While VANET requires rapid and reliable transmission, packet transmission in VANET is unstable because of high mobility. Many routing protocols have been proposed and assessed to improve the efficiency of VANET. However, topology-based routing protocols generate heavy overhead and long delay, and position-based routing protocols have frequent packet loss due to inaccurate node position. In this paper, we propose a position-based routing repair algorithm to improve the efficiency of VANET. This algorithm is proposed based on the premise that AODV (-PGB) can be used effectively in VANET, if the discovery, maintenance and repair mechanism of AODV is optimized for the features of VANET. The main focus of this algorithm is that the relay node can determine whether its alternative node exits and judge whether the routing path is disconnected. If the relay node is about to swerve from the routing path in a multi-hop network, the node recognizes the possibility of path loss based on a defined critical domain. The node then transmits a handover packet to the next hop node, alternative nodes and previous node. The next node repairs the alternative path before path loss occurs to maintain connectivity and provide seamless service. We simulated protocols using both the ideal traffic model and the realistic traffic model to assess the proposed algorithm. The result shows that the protocols that include the proposed algorithm have fewer path losses, lower overhead, shorter delay and higher data throughput compared with other protocols in VANET.

• Journal of the korean academy of Pediatric Dentistry
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• v.2 no.1
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• pp.67-75
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• 1975

The conserative treatment of the necrotic and infected primary molars is often necessary in order to avoid extractions which may lead to inability to masticate or loss of space and subsequent problems concerning the development of the occlusion in the permanent dentition. The purpose of this study was to evaluate the clinical significance of the conservative treatment of the infected primary molars with necrotic pulps employing the formocresol pulpotomy technique same as in vital teeth and surgical intervention in the cases with a parulis, fistula or cellulitis. The materials consisted of 25 primary molars of 9 boys and 4 girls ranging in age from 4 to 7 years. This study included clinical and radiographic observation at 3-month intervals postoperatively. The following results were obtained. 1. Clinically, 20 cases of 25 were successful, exhibiting no clinical problems such as fistula, mobility, toothache and tenderness to percussion, etc. 5 cases were regarded as failures. 2. Radiographiclly, 14 cases revealed normal features, in 6 cases slight rarefaction was observed in the periapical and interradicular region, and marked periapical and interradicular rarefaction was observed in 5 cases. 3. Marked bony deposition was observed in the periapical and interradicular regions in all the remainder except for 5 failurese. 4. Pathologic root resorption was observed in 2 cases. 5. No alveolodental ankylosis was observed. 6. Regeneration of the dental sac of the permanent tooth was observed in 1 case of 2 cases which had revealed loss of the dental sac.

• International Journal of Railway
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• v.6 no.2
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• pp.33-44
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• 2013

In recent years, energy consumption in the transportation sector by expanding motorization continues to increase in almost every country in the world. Moreover, the growth rate of the transportation energy consumption is significantly higher than those of the civilian and industrial sectors. Therefore, every country strives to reduce its dependence on private transport, which is the main contributor to the transportation energy consumption. In many countries, concepts such as Transit Oriented Development (TOD) or New Urbanism, which controls road traffic by increasing the proportion of the public transportation significantly, have been implemented to encourage a modal shift to public transport. However, the level of change required for eliminating environmental problems is a challenging task. Minimizing transportation energy consumption by controlling the increase of the traffic demand and maintaining the level of urban mobility simultaneously is a pressing dilemma for each city. Grasping the impact of the diversity of the urban transport and infrastructure is very important to improve transportation energy efficiency. However, the potential for reducing urban transportation energy consumption has often been ineffectively demonstrated by the diversity of cities. Therefore, the accuracy of evaluating the current efficiency rate of the urban energy consumption is necessary. Nevertheless, quantitative analyses related to the efficiency of transportation energy consumption are scarce, and the research on the current condition of consumption efficiency based on international quantitative analysis is almost nonexistent. On the basis of this background problem definitions, this research first built a database of the transportation energy consumption of private modes in 119 cities, with an attempt to reflect individual travel behaviors calculated by Person Trip data. Subsequently, Data Envelopment Analysis (DEA) was used as an assessment method to evaluate the efficiency of transportation energy consumption by considering the diversity of the urban traffic features in the world cities. Finally, we clarified the current condition of consumption efficiency by attempting to propose a target values for improving transportation energy consumption.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.3
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• pp.733-739
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• 2011

Recently, a lots of research proposals and results on mobile sensor network are actively announced. The most of such works are based on general-purposed network simulators such as ns-2, mathlab, etc. But, It is not easy to model and simulate the detail activities of each sensor node, data deliveries between them, and its cost such as power consumption and resource utilization, so that the simulation results of those simulators show the limited aspects of overall networks features or performance metrics. In this paper proposed, power consumption of each node, performance, mobility, and location information in operation-level of the network that can simulate a wireless sensor network simulator platform. Because the network routing algorithm analysis of being developed in an existing becomes available, the proposed simulator can usability in the new network routing algorithm development.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37A no.9
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• pp.762-771
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• 2012

In this paper, we propose an adaptive power control scheme employing a self-optimization concept in femtocell systems, in order to improve system capacity, thereby reducing call-drop probability. In the proposed scheme, each femto base station(FBS) controls individual channel's transmission power base on two parameters; the neighboring cell's transmission power for each individual channel which is delivered from a femto-gateway and the received power strength from neighboring cells which is periodically measured by means of a spectrum sensing. Adaptive adjustment of individual channel's transmission power in accordance with femto mobile station(FMS) mobility features can also reduce undesirable handovers and evenly distribute traffic load over all femtocells. In addition, the manipulative control of channel's transmission power is able to keep the system coverage and the call-drop probability within an acceptable range, regardless of density of femtocells. Computer simulation shows that the proposed scheme outperforms existing schemes in terms of the system coverage and the call-drop probability.

• Journal of Digital Contents Society
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• v.11 no.4
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• pp.433-443
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• 2010

In this paper, we provide a comprehensive overview and classification on a wide range of the existing location management schemes which have been reported for wireless cellular networks and Mobile IP-based networks, respectively. In addition, from the various previous literature, we derive common key conceptual techniques, their main design goals and performance considerations on them, which can provide a useful guidance for understanding location management schemes regardless of network types. The aim of this paper is not to propose a new scheme for location management, but to highlight the various key design features involved in the design of the existing location management schemes, and to enhance an insight into the fundamental principles and techniques for designing more efficient and optimized location management scheme in future wireless mobile networks. We expect that regardless of network types, these underlying fundamental principles and conceptual techniques could be also easily tailored for more efficient mobility/QoS support in future mobile computing environments.

• Journal of Periodontal and Implant Science
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• v.35 no.2
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• pp.311-319
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• 2005

In order to examine the effects of advanced periodontitis on the dental pulps, 38 extracted human teeth were examined histologically. The 38 teeth had a positive or negative state in the electric pulp test(EPT). In addition, almost of the 38 teeth had a deep pocket and severe mobility, and floating state. A medical and dental history was elicited. The extracted teeth fixed in 10% neutral formalin solution. The general tissue processing method was followed. The tissue block including the teeth was prepared for optical microscopy using hematoxillin-eosin staining. Among the 38 periodontally involved teeth, the dental pulps were respectively intact in 12(31%), and a pulp stone(or linear calcifications) was found in 18 teeeth(47%). In addition, 17 teeth(44%) had pulps exhibiting inflammatory reactions with varying intensities, such as hyperemia, pulp abscess, pulp necrosis. Among the 38 periodontally involved teeth, 37 teeth tested a positive to the EPT, and 7 teeth tested negative. The EPT positive 37 teeth had various histological features such as 7 normal pulp(18%), 17 pulp stone(44%), 1 hyperemia (2%), 9 pulpitis(23%), 5 root resorption(13%), 3 pulp abscess(7%), and 3 pulp necrosis(7%), In conclusion, it is suggested that in the EPT positive teeth, advanced periodontally involved teeth can cause inflammation of the dental pulp.

• Convergence Security Journal
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• v.11 no.1
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• pp.11-18
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• 2011

Wireless mesh network technology with transmission speeds similar to wired and wireless technology means to build, compared with wired networks, building a more efficient network to provide convenience and flexibility. The wireless mesh network router nodes in the energy impact of the mobility is less constrained and has fewer features entail. However, the characteristics of various kinds due to network configuration settings and the choice of multiple paths that can occur when the system overhead and there are many details that must be considered. Therefore, according to the characteristics of these network routing technology that is reflected in the design and optimization of the network is worth noting. In this paper, a multi-path setting can be raised in order to respond effectively to the problem of the router node data loss and bandwidth according to traffic conditions and links to elements of the hop count evaluation by using a genetic algorithm as a workaround for dynamic routing the routing metric for wireless mesh network scheme is proposed.

• Journal of Genetic Medicine
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• v.7 no.2
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• pp.151-155
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• 2010

Apert syndrome is a rare congenital anomaly characterized by craniofacial malformations and severe symmetrical syndactyly of fingers and toes. This syndrome is caused by a genetic mutation; the S253 mutation is common, though the P253R mutation is not as frequent. Common symptoms include skeletal malformations, poor joint mobility, eye and ear problems, cleft palate, and orthodontic and other dental problems. We report a case of an infant with the common morphological features of Apert syndrome. Interestingly, she was found to have the P253R mutation in FGFR2 exon VIII, which has been less commonly observed in Korea. A brief review of the literature is included.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.2
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• pp.82-89
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• 2006

Bone metastasis is a common sequelae of solid malignant tumors such as prostate, breast, lung, and renal cancers, which can lead to various complications, including fractures, hypercalcemia, and bone pain, as well as reduced performance status and quality of life it occurs as a result of a complex pathophysiologic process between host and tumor cells leading to cellular invasion, migration adhesion, and stimulation of osteoclastic and osteoblastic activity. Several sequelae occur as a result of osseous metastases and resulting bone pain can lead to significant debilitation. A multidisciplinary approach is usually required not only to address the etiology of the pain and its complicating factors but also to treat the patient appropriately. Pharmaceutical therapy of bone pain, includes non-steroidal analgesics, opiates, steroids, hormones, bisphosphonates, and chemotherapy. While external beam radiation therapy remains the mainstay of pain palliation of a solitary lesions, bone seeking radiopharmaceuticals have entered the therapeutic armamentarium for the treatment of multiple painful osseous lesions. $^{32}P,\;^{89}SrCl,\;^{153}Sm-EDTMP,\;^{188}Re/^{186}Re-HEDP,\;and\;^{177}Lu-EDTMP$ can be used to treat painful osseous metastases. These various radiopharmaceuticals have shown good efficacy in relieving bone pain secondary to bone metastasis. This systemic form of metabolic radiotherapy is simple to administer and complements other treatment options. This has been associated with improved mobility in many patients, reduced dependence on narcotic and non-narcotic analgesics, improved performance status and quality of life, and, in some studios, improved survival. All of these agents, although comprising different physical and chemical characteristics, offer certain advantages in that they are simple to administer, are well tolerated by the patient if used appropriately, and can be used alone or in combination with the other forms of treatment. This article illustrates the salient features of these radiopharmaceuticals, including the usual therapuetic dose, method of administration, and indications for use and also describe about the pre-management checklists, and jndication/contraindication and follow-up protocol.