• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37 no.8B
• /
• pp.657-667
• /
• 2012

In the MPR selection algorithm of Optimized Link State Routing (OLSR), each node selects own MPRs independently, so most of nodes are selected to MPR at least once. To cope with this problem, the MPR candidate selection algorithm was proposed. The MPR candidate selection algorithm can reduce the number of MPRs, but the efficiencies of route and connectivity decline due to decreased number of MPRs. So, in this paper, we propose the Significant Multi-Point Relay (S-MPR) selection algorithm which can enhance the performance of ad hoc network by improving the MPR selection algorithm of OLSR. In proposed S-MPR selection algorithm, each node selects the most important node to S-MPR to guarantee the connectivity then selects remaining MPRs in MPR candidates. So proposed S-MPR selection algorithm can reduce the overhead of many MPRs without decline of routing performance. To show the performance gain of proposed S-MPR selection algorithm, we simulate the proposed S-MPR selection algorithm by using OPNET.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37B no.12
• /
• pp.1128-1137
• /
• 2012

In this paper, we propose an improved MPR selection method considering mobility and density of nodes for ad-hoc networks. In Optimized Link State Routing(OLSR), a node selects 1-hop Multi-Point Relay(MPR) nodes to cover all 2-hop neighbor nodes. In a high population area, many nodes are likely to be selected as MPR nodes by their neighbors. This leads to increase in contention among MPR nodes and may decrease overall performance of the network. In addition, when an MPR node leaves the communication range of its MPR selector node, it can no longer perform as the MPR node and the performance of the network may also decrease. In this paper, we propose an MPR selection method which measures the mobility and density of nodes by exchanging the hello messages and gives the priorities to the nodes for MPR selection. Performance evaluation results using OPNET show that the proposed method is superior to OLSR or the MPR candidate method in terms of connectivity and throughput.

• Imaging Science in Dentistry
• /
• v.33 no.4
• /
• pp.199-205
• /
• 2003

Purpose: To compare the visibility of the mandibular canal at the different radiographic methods such as conventional panoramic radiographs, Vimplant multi planar reformatting (MPR)-CT panoramic images, Vimplant MPR-CT paraxial images and film-based DentaScan MPR-CT images. Materials and Methods: Data of 11 mandibular dental implant patients, who had been planned treatment utilizing both panoramic and MPR-CT examination with DentaScan software (GE Medical systems, Milwaukee, USA), were used in this study. The archived axial CT data stored on CD-R discs were transferred to a personal computer with 17' LCD monitor. Paraxial and panoramic images were reconstructed using Vimplant software (CyberMed Inc., Seoul, Korea). Conventional panoramic radiographs, monitor-based Vimplant MPR-CT panoramic images, monitor-based Vimplant MPR-CT paraxial images, and film-based DentaScan MPR-CT images were evaluated for visibility of the mandibular canal at the mental foramen, 1 cm, 2 cm, and 3 cm posterior to mental foramen using the 4-point grading score. Results: Vimplant MPR-CT panoramic, paraxial, and DentaScan MPR-CT images revealed significantly clearer images than conventional panoramic radiographs. Particularly at the region 1 em posterior to mental foramen, conventional panoramic radiographs showed a markedly lower percentage of 'excellent' mandibular canal images than images produced by other modalites. Vimplant MPR-CT and DentaScan MPR-CT images did not show significant difference in visibility of the mandibular canal. Conclusion: The study results show that Vimplant and DentaScan MPR-CT imaging systems offer significantly better images of the mandibular canal than conventional panoramic radiograph.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.34 no.10B
• /
• pp.1043-1049
• /
• 2009

Broadcast of sink node is used for network management, data collection by query and synchronization in wireless sensor networks. Simple flooding scheme induces the broadcast storm problem. The MPR based broadcast schemes reduce redundant retransmission of broadcast packets. MPR is a set of one hop neighbor nodes which have to relay broadcast message to cover all two hop neighbors. Though MPR can reduce redundant retransmission remarkably, it still suffers from energy waste problem caused by collision and duplicate packets reception. This paper proposes a new MPR based sink broadcast scheme using 3-channel. The proposed scheme reduces energy consumption by avoiding duplicate packet reception, while increases reliability by reducing collision probability remarkably. The results of analysis and simulation show that the proposed scheme is more efficient in energy consumption compared to the MPR based scheme. The result also shows that the proposed scheme reduces delivery latency by evading a contention with other relay nodes and improves reliability of broadcast message delivery by reducing collision probability.

• The Journal of Korean Medicine
• /
• v.30 no.6
• /
• pp.69-79
• /
• 2009

Objective: In this study, the immunomodulatory activity of a mixture of wild Panax ginseng and red-mold rice extracts (MPR) on RAW 264.7 macrophage cells in the presence and absence of methotrexate (MTX), an anti-cancer drug, was investigated. Methods and Results: In the cell viability, MPR showed a significant cell proliferation and inhibited cell regression by red-mold rice (RMR) alone or MTX alone. MPR induced moderate increase in nitric oxide (NO) production. NO production and inducible nitric oxide synthase (iNOS) mRNA expression by LPS decreased after MPR treatment. In addition, MPR slightly induced COX-2 mRNA expression, but it did not affect the expression of COX-2 mRNA by LPS treatment. In RT-PCR analyses, MPR induced IL-$1{\alpha}$, IL-$1{\beta}$, IL-6, and TNF-$\alpha$ mRNA expression, but had no effect on IL-10 and TGF-$\beta$, regardless of MTX treatment. Furthermore, MPR did not interfere with the cytotoxicity of MTX against MCF-7 human breast carcinoma cells. Conclusions: MPR is efficacious in protecting against MTX-induced cell regression as a result of macrophage activation, resulting in induction of cytokine expression, implying that MPR could be considered an adjuvant in MTX-chemotherapy.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.10 no.4
• /
• pp.1571-1589
• /
• 2016

Nodes in MANETs are battery powered which makes energy an invaluable resource. In OLSR, MPRs are special nodes that are selected by other nodes to relay their data/control traffic which may lead to high energy consumption of MPR nodes. Therefore, employing energy efficient MPR selection mechanism is imperative to ensure prolonged network lifetime. However, misbehaving MPR nodes tend to preserve their energy by dropping packets of other nodes instead of forwarding them. This leads to huge energy loss and performance degradation of existing energy efficient MPR selection schemes. This paper proposes an energy efficient secure MPR selection (ES-MPR) technique that takes into account both energy and security metrics for MPR selection. It introduces the concept of 'Composite Eligibility Index' (CEI) to examine the eligibility of a node for being selected as an MPR. CEI is used in conjunction with willingness to provide distinct selection parameters for Flooding and Routing MPRs. Simulation studies reveal the efficiency of ES-MPR in selection of energy efficient secure and stable MPRs, in turn, prolonging the network operational lifetime.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2010.10a
• /
• pp.349-351
• /
• 2010

Recently, we were able to get thinner projection supplied by multi detector CT. Not only 'axial projection' is used to decode the examination but asks resctructured projections in various directions. MPR technique is capable of drawing flexible curves to produce projection reenactment which enables describing details of a part that is desired but it has a disadvantage that curvy blood vessels like 'willis circle artery' distorting. This essay suggested Curved MPR method based on different disorders which was improved using distinction of HU value along with existing MPR method. After reconstructing the projection using the suggested method, the projection was transmitted by using PACS and it confirmed its usefulness of decoder's efficiency diagnosis.

• Journal of Periodontal and Implant Science
• /
• v.31 no.4
• /
• pp.811-822
• /
• 2001

최근 임플란트를 원하고, 필요로 하는 환자가 증가하면서 술전의 정확한 진단이 보다 중요해졌고 다양한 진단방법이 소개되고 이용되어져 왔다. 그 중 보편적으로 가장 널리 사용되어지는 방법이 방사선 촬영법이고 그 중에서도 파노라마방사선사진이다. 하지만 파노라마방사선사진의 용이함과 간편성에도 불구하고 그 방법 자체가 가지고 있는 한계점 때문에 CT/MPR(Computer Tomography/Multiplanar Reformatting)이 일부 환자에서는 반드시 필요하다는 주장이 대다수이다. 본 연구의 목적은 하악 구치부에 임플란트 시술을 받은 환자를 대상으로 파노라마방사선사진의 확대율을 알아보고 파노라마방사선사진과 CT/MPR에서 치조정-하악관간 거리가 실제 어느 정도 차이를 보이는지, 그리고 CT/MPR에 대한 파노라마방사선사진의 확대율에 환자의 하악골의 경사도와 하악관의 해부학적 위치가 어떤 영향을 미치는지를 알아보는 것이다. 본 연구는 서울대학 치과병원 치주과를 내원하여 하악구치부에 Dental Implant 시술을 받은 15명의 환자, 32개 부위를 대상으로, 임플란트 시술을 위한 술전 파노라마방사선사진과 CT/MPR, 술후의 파노라마방사선사진, CT/MPR상을 자료로, 임플란트가 식립될 위치에서 치조정에서 하악관의 길이, 하악골의 협설폭경, 하악골의 설측면에서 하악관의 수평길이, 임플란트 매식체의 설측에서 하악관까지의 수평거리를 계측하였고 이 해부학적 계측치들이 CT/MPR에 대한 파노라마방사선사진의 확대율과 어떤 상관관계에 있는지 Pearson's correlation coefficient test를 이용해 살펴보았다. 1. CT/MPR에 대한 파노라마방사선사진의 확대율은 CT/MPR상에서 하악골 단면의 협설폭경(Pearson test에서의 상관관계 분석시, 상관계수 r=-0.604), 임플란트 매식체의 설측에서 하악관까지의 수평거리(r=-0.515), 하악골의 설측면에서 하악관까지의 수평거리(r=-0.640)와 뚜렷한 음적 선형관계가 있었다. 2. CT/MPR에 대한 파노라마방사선사진의 확대율은 CT/MPR상에서 하악골의 장축의 각도와는 뚜렷한 양적 선형관계(Pearson test에서의 상관관계 분석시, 상관계수 r=-0.446)가 있었다. 3. 여러 요소중 CT/MPR에 대한 파노라마방사선사진의 확대율과 가장 유의성있는 연관성을 보이는 것은 CT/MPR상에서 하악골의 설측면에서 하악관까지의 수평거리였다(r=-0.640) 4. CT/MPR에 대한 파노라마방사선사진의 확대율은 일반적으로 생각되어지는 파노라마방사선사진의 확대율 125%보다 큰, 약 135%로 나왔다. 이상의 결과로 볼 때, 하악골의 설측면에서 하악관까지의 수평거리가 CT/MPR에 대한 파노라마방사선사진의 확대율에 가장 영향을 미치는 요소로 추정되며 확대율은 125%보다 높은 것으로 나타났다.

• Management & Information Systems Review
• /
• v.21
• /
• pp.29-47
• /
• 2007

The purpose of this study is to analyze the case on the strategic MPR that has rapidly growing for years. And the Brand, which was at first used to be distinguished from many other products or services, is going through its gradually expanded definition, not merely for the highlight of the distinctions. This study was performed to review the literature on concept and meaning of Marketing Public Relations(MPR) which was used for IMC planning and to identify formation, development, and functional characteristics of MPR. MPR is a series of public communication act in order to gain credibility on their products and services with consumers and prospects from consumer-oriented viewpoint. The subject of the study are Colleges or Universities who try hard to work their various and strategic PR communication. The results of this research indicates that maximization of the integrated effect between marketing and public relations shall be achieved in planning MPR strategy. The meaning of this study is to verify the significance and need of the Colleges or Universities' specialized characteristics in strategic MPR activities. It is expected that this research will provide meaningful suggestions to PR and marketing practitioners.

• Korean Journal of Digital Imaging in Medicine
• /
• v.12 no.2
• /
• pp.139-143
• /
• 2010

Two-dimensional(2D) images like Multi Planar Reconstruction(MPR) Image or Maximum Intensity Projection(MIP) were used for the purpose of diagnosis, but MPR image's quality were limited due to its superior limit of Z-axis ability to produce permitted radiation exposure virtuous in the permitted time limit from the existing Spiral CT. However, in company with the development of the Multi Detector Computed Tomography(MDCT), we were able to get the Data with the equal amount of Voxel, also get varied reconstructions as in the aspect of our needs. This present study propose a reconstruction technique which is to extract a field using Region of interest(ROI) segmentation method for improvement of the quality of the medical image and after that reconstruct the concerned part using the four-directed symmetry method of the oval, than using the reconstructed data, reorganize the image by using the Curved MPR method. If current proposed method is used, it is highly effective because of its ability to accurately display the disease concerned part, which will reduce the decoding time and also effectively provide information based on the accuracy of the decode.