• Title/Summary/Keyword: group mobility

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Performance Improvement of Delay-Tolerant Networks with Mobility Control under Group Mobility

  • Xie, Ling Fu;Chong, Peter Han Joo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.6
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    • pp.2180-2200
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    • 2015
  • This paper considers mobility control to improve packet delivery in delay-tolerant networks (DTNs) under group mobility. Based on the group structure in group mobility, we propose two mobility control techniques; group formation enforcement and group purposeful movement. Both techniques can be used to increase the contact opportunities between groups by extending the group's reachability. In addition, they can be easily integrated into some existing DTN routing schemes under group mobility to effectively expedite the packet delivery. This paper is divided into 2 parts. First, we study how our proposed mobility control schemes reduce the packet delivery delay in DTNs by integrating them into one simple routing scheme called group-epidemic routing (G-ER). For each scheme, we analytically derive the cumulative density function of the packet delivery delay to show how it can effectively reduce the packet delivery delay. Then, based on our second proposed technique, the group purposeful movement, we design a new DTN routing scheme, called purposeful movement assisted routing (PMAR), to further reduce the packet delay. Extensive simulations in NS2 have been conducted to show the significant improvement of PMAR over G-ER under different practical network conditions.

A Scalable Multicasting with Group Mobility Support in Mobile Ad Hoc Networks

  • Kim, Kap-Dong;Lee, Kwang-Il;Park, Jun-Hee;Kim, Sang-Ha
    • Journal of Information Processing Systems
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    • v.3 no.1
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    • pp.1-7
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    • 2007
  • In mobile ad hoc networks, an application scenario requires mostly collaborative mobility behavior. The key problem of those applications is scalability with regard to the number of multicast members as well as the number of the multicast group. To enhance scalability with group mobility, we have proposed a multicast protocol based on a new framework for hierarchical multicasting that is suitable for the group mobility model in MANET. The key design goal of this protocol is to solve the problem of reflecting the node's mobility in the overlay multicast tree, the efficient data delivery within the sub-group with group mobility support, and the scalability problem for the large multicast group size. The results obtained through simulations show that our approach supports scalability and efficient data transmission utilizing the characteristic of group mobility.

Clinical Evaluation of Tooth Mobility Following Root Planing and Flap Operation (치근활택술과 치은박리소파술 후 치아동요도 변화에 관한 연구)

  • Pang, Eun-Kyoung;Chai, Jung-Kiu;Kim, Chong-Kwan;Cho, Kyoo-Sung
    • Journal of Periodontal and Implant Science
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    • v.29 no.4
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    • pp.893-914
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    • 1999
  • Tooth mobility may be the decisive factor that determines whether dental treatment of any kind is undertaken. Although tooth mobility in isolation says little in itself, the finding of increased tooth mobility is of both diagnostic and prognostic importance. Only the detection of an increase or decrease in mobility makes an evaluation possible. Thus prior to treatment, we must understand the pathologic process causing the observed the tooth mobility and decide whether the pattern and degree of observed tooth mobility is reversible or irreversible. And then it must be decided whether retention and treatment or extraction and replacement. The purpose of this study was to compare tooth mobility at different time period during root planing and flap operation and to relate changes in mobility to each treatment method. Twenty-one patients (287 teeth) with chronic adult periodontitis were treated with root planing(control group) and flap operation(experimental group), and each group was divided 3 subgroups based upon initial probing pocket depth (1-3mm, 4-6mm, 7mm and more). Tooth mobility was measured with $Periotest^{(R)}$ at the day of operation, 4 days, 1 week, 2 weeks, 3 weeks, 4 weeks, 8 weeks, 12 weeks after each treatment. Tooth mobility, attachment loss, radiographic bone loss, and bleeding on probing were measured at the day of operation, 4 weeks, 8 weeks and 12 weeks after treatment. 1. In group initial probing depth was 1-3mm, tooth mobility had no significant difference after root planing and flap operation. 2 . In group initial probing depth was 4-6mm, 7mm and more, tooth mobility had decreased in 12 weeks after root planing(p<0.01). And the mobility had increased after flap operation(p<0.01) and was at peak in 1 week, and decreased at initial level in 4 weeks, below the initial level in 12 weeks(p<0.01). 3. In 1 week, significant difference in tooth mobility between control and experimental group was found(p<0.01) but, in 12 weeks no difference between two groups was found. 4. Change of immediate tooth mobility after treatment was more larger in deep pocket than in shallow one. In group with the same probing pocket depth, the change of tooth mobility in molar group was greater than that of premolar group. 5. Tooth mobility before treatment was more strongly correlated with radiographic bone loss (r=0.5325) than probing depth, attachment loss and bleeding on probing, in 12 weeks after treatment, was more strongly correlated with attachment loss($r^2$=0.4761) than probing depth and bleeding on probing. Evaluation of the treatment effect and the prognosis after root planing and flap operation were meaningful on tooth initial probing depth 4mm and more. After flap operation, evaluation of the prognosis should be performed at least in 4 weeks and in 12 weeks after treatment, no difference in tooth mobility between two groups was observed. Radiographic bone loss and attachment loss were good clinical indicators to evaluate tooth mobility.

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Effects of Thoracic Mobility Exercise Program on Pain, Proprioception, and Static Balance Ability in Patients with non-Specific Chronic Low Back Pain

  • Donghwan Park;Kang-Seong Lee
    • Physical Therapy Rehabilitation Science
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    • v.13 no.1
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    • pp.1-7
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    • 2024
  • Objective: The objective of this study was to investigate the effect of the thoracic mobility exercise program on pain, proprioception, and static balance ability in patients with non-specific chronic low back pain. Design: Randomized controlled trial design. Methods: Thirty patients with non-specific chronic low back pain participated in this study. The participants were randomized into the thoracic mobility exercise group (n=15) and the lumbar stabilization exercise group (n=15). Both groups received traditional physical therapy for 30 minutes per session. In addition, the thoracic mobility exercise group and the lumbar stabilization exercise group each exercise 3 times a week for 6 weeks. All participants were measured visual analog scale, proprioception test, and static balance ability before and after the intervention. Results: After 6 weeks of interventions, the thoracic mobility exercise group showed greater improvement in visual analog scale, proprioception test, and static balance ability than the LSE group (p<0.05). Further, the thoracic mobility exercise group had significant Enhancements in all measured variables compared to the baselinetest (p<0.05). However, the lumbar stabilization exercise group had significant improvement only visual analog scale, and static balance ability compared to the baselinetest (p<0.05). Conclusions: Our investigation demonstrates that the thoracic mobility exercise is an effective intervention method for improving pain, proprioception, and static balance ability in patients with non-specific chronic low back pain.

A Method for Group Mobility Model Construction and Model Representation from Positioning Data Set Using GPGPU (GPGPU에 기반하는 위치 정보 집합에서 집단 이동성 모델의 도출 기법과 그 표현 기법)

  • Song, Ha Yoon;Kim, Dong Yup
    • KIPS Transactions on Software and Data Engineering
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    • v.6 no.3
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    • pp.141-148
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    • 2017
  • The current advancement of mobile devices enables users to collect a sequence of user positions by use of the positioning technology and thus the related research regarding positioning or location information are quite arising. An individual mobility model based on positioning data and time data are already established while group mobility model is not done yet. In this research, group mobility model, an extension of individual mobility model, and the process of establishment of group mobility model will be studied. Based on the previous research of group mobility model from two individual mobility model, a group mobility model with more than two individual model has been established and the transition pattern of the model is represented by Markov chain. In consideration of real application, the computing time to establish group mobility mode from huge positioning data has been drastically improved by use of GPGPU comparing to the use of traditional multicore systems.

Swarm Group Mobility Model for Ad Hoc Wireless Networks

  • Kim, Dong-Soo S.;Hwang, Seok-K.
    • Journal of Ubiquitous Convergence Technology
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    • v.1 no.1
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    • pp.53-59
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    • 2007
  • This paper proposes a new group mobility model for wireless communication. The mobility model considers the psychological and sociological behavior of each node and the perception of other nodes for describing interactions among a set of nodes. The model assumes no permanent membership of a group, capable of capturing natural behaviors as fork and join. It emulates a cooperative movement pattern observed in mobile ad hoc networks of military operation and campus, in which a set of mobile stations accomplish a cooperative motion affected by the individual behavior as well as a group behavior. The model also employs a physic model to avoid a sudden stopping and a sharping turning.

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Mobility Management of M2M Devices with Grouping in the LTE System (LTE 시스템에서 그룹 기반 M2M 단말 이동성 관리)

  • Roh, Hee-Tae;Lee, Jang-Won
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37B no.12
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    • pp.1119-1127
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    • 2012
  • The one of features of M2M communications, which are recently attracted attention as a future business of mobile communications, is that there is a large number of devices compared with traditional communication services. Hence, the control signal that are generated by the M2M devices may cause a significant congestion in the network and in order to solve this problem, a standardization is progressing for reducing the redundant signaling by managing M2M devices as a group in 3GPP standardization. In this paper, we propose a method of group based mobility management by managing M2M devices that have the same mobility as a group. In the proposed method, M2M devices that have the same mobility are grouped by the Mobility Management Entity (MME) and the MME elects a group header among the M2M devices in the group. Then, the group header performs the Tracking Area Update (TAU) on behalf of the group members to reduce the signaling overhead of mobility management. With the proposed method, we can achieve 80% decrease of the signaling overhead of mobility management compared with the case where each M2M device individually performs its TAU procedure.

The Effects of Myofascial Trigger Point Release and Mobility Exercise on Pain and Functions in Patient with Rotator Cuff Tendinopathy

  • Shin, Beom-Cheol;Choi, Wonjae;Jung, Jihye;Lee, Seungwon
    • Physical Therapy Rehabilitation Science
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    • v.11 no.2
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    • pp.269-278
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    • 2022
  • Objective: The aim of this study was to evaluate the effects on pain and function of patients with rotator cuff tendinopathy when applying trigger point of infraspinatus and teres minor to myofascial trigger point release (MFR) plus mobility exercise and MFR. Design: A randomized controlled trial. Methods: The total participants were 30patients and were separated to MFR plus mobility exercise group(n=15) and MFR group (n=15) according to the randomized treatment method. The MFR was performed at two infraspinatus tampon points and one teres minor tampon point for twice a week for 4 weeks and the treatment time was 6 minutes 20 seconds in each position. The MFR group also carried out the myofascial trigger point release in the same way as the MFR plus mobility exercise group. Results: The MFR plus mobility exercise group significantly reduced objective and subjective pain (p<0.05). The range of motion of the shoulder joint flexion and external rotation, Quick-Disability of the Arm, shoulder and Hand, and Shoulder Pain and Disability Index were significantly improved in the group to which MFR plus mobility exercise was applied (p<0.05). Conclusions: These results confirmed that MRF plus mobility exercise is more effective in relieving shoulder pain and improving function in rotator cuff tendinopathy.

The Effects on the Pulmonary Function of 20s Subjects according to Thoracic Mobility Exercise and Place Running Exercise (흉추가동운동과 제자리 달리기 운동이 20대 대학생의 폐기능에 미치는 영향)

  • Kim, Jong-woo;Hwang, Hyeng-jun;park, Yoon-gi
    • The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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    • v.22 no.2
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    • pp.65-69
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    • 2016
  • Background: The purpose of this study was to determine whether place running exercise that combines thoracic mobility exercise program increases pulmonary function of the 20s subjects. Method: Thirty subjects in their 20s were randomly assigned to on experimental group (n=15) or control group (n=15). Over the course of four weeks, the experimental group participated in place running exercise that combines thoracic mobility exercise program for 30 minutes three times per week and the control group participated in place running exercise and thoracoabdominal stretching exercise for 30 minutes three times per week. Subjects were assessed pre-test and post-test by measurement of pulmonary function Results: Our findings show that the experimental group had significant difference in expiratory reserve volume and vital capacity and maximal voluntary capacity (p<.05). In the comparison of the two groups, the experimental group had higher vital capacity and maximal voluntary capacity than the control group. Conclusion: In this study, the experimental group showed greater improvement in pulmonary function than the control group, which indicates that the place running exercise that combines thoracic mobility exercise program exercise is effective at increasing the pulmonary function.

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Mobility-Adaptive Routing Update Scheme for Wireless Networks with Group Mobility (그룹 이동성을 가지는 무선 네트워크에서 이동 적응적인 라우팅 업데이트 구조)

  • Kang, Hyun-Jae;Lim, Sung-Gook;Jeon, Hahn-Earl;Lee, Jai-Yong;Park, Soo-Bum;You, Young-Bin
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.37 no.1B
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    • pp.39-49
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    • 2012
  • With group mobility, minimizing routing overhead among intra-group nodes can be achieved by making longer the routing update period, which may lead to degradation of inter-group's routing performance and consequently the inter-group packet delivery success ratio will be decreased. To reduce the inter-group routing overhead without lowering the inter-group packet delivery success ratio, a mobility-adaptive routing update(MARU) scheme is proposed in this paper. Main idea of the proposed scheme is group-based mobility prediction and updating routing paths by selecting intermediate common relay groups.