• Title/Summary/Keyword: Mobility control

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An Adaptive AODV Algorithm for Considering Node Mobility (노드 이동성을 고려한 적응형 AODV 알고리즘)

  • Hong, Youn-Sik;Hong, Jun-Sik;Lim, Hwa-Seok
    • Journal of KIISE:Information Networking
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    • v.35 no.6
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    • pp.529-537
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    • 2008
  • AODV routing protocol is intended for use by mobile' nodes in an ad-hoc network. In AODV nodes create routes on an on-demand basis. As the degree of node mobility becomes high, however, the number of the control packets, RREQ and RREP messages, have increased so rapidly. The unexpected increases in the number of the control packets cause the destination node to decrease the packet receiving rate and also to increase the overall energy consumption of such a network. In this paper, we propose a novel method of adaptively controlling the occurrences of such RREQ messages based on AIAD (additive increase additive decrease) under a consideration of the current network status. We have tested our proposed method with the conventional AODV and the method using timestamp based on the three performance metrics, i.e.. how long does node moves, node velocity, and node density, to compare their performance.

A Scheduling Approach using Gradual Mobility Reduction for Synthesizing Pipelined Datapaths (파이프라인 데이터패스 합성을 위한 점진적 배정가능범위 축소를 이용한 스케줄링 방법)

  • Yoo, Hee-Jin;Oh, Ju-Young;Lee, Jun-Yong;Park, Do-Soon
    • The KIPS Transactions:PartA
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    • v.9A no.3
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    • pp.379-386
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    • 2002
  • This paper presents a scheduling approach for synthesizing pipelined datapaths under resource constraints. Our approach builds up a schedule based on gradual mobility reduction in contrast to other algorithms of previous researches, where an operation being scheduled is selected by using a priority function. The proposed method consists of a scheduling algorithm and a decision algorithm for detecting any violation against resource constraints. Our approach evaluates whether or not a scheduling solution can exist in case an operation temporarily is assigned to the earliest or latest control step among the assignable steps for the operation. If a solution cannot be found, it is impossible to assign the operation to that step due to a violation against resource constraints, and so we can eliminate that control step. This process is iterated until a reduction of mobility for all operations can not be obtained. Experiments on benchmarks show that this approach gains a considerable improvement over those by previous approaches.

A study of distribution, prevalence and relationship of the localized periodontitis of first and second molar root fusion (제 1, 2 대구치 치근융합의 발생빈도와 분포 및 국소적 치주염과의 관련성 조사)

  • Choi, Byung-Kook;Hong, Ki-Seok;Chung, Chin-Hyung;Lim, Sung-Bin
    • Journal of Periodontal and Implant Science
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    • v.36 no.2
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    • pp.503-513
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    • 2006
  • The purpose of this study was to determine the distribution, prevalence and relationship of the localized periodontitis of root fusion in maxillary and mandibular molars. One hundred patients who had eight maxillary and mandibular molars(third molars excluded) were consecutively selected for the study subjects. The subjects provided a total of 800 molars, i. e., 400 maxillary and 400 mandibular molars. A decision about root fusion was made on the radiographic examination. Probing depth, plaque index, gingival index and mobility were measured. The results were as follows. 1. 15.9% of the molars had a fused root. 22% of the maxillary molars and 9.8% of the mandibular molars had a fused molars. 2. In maxillary molars, the results of probing depth, plaque index, gingival index, mobility are more higher in test group than in control group, and there was a significantly difference except plaque index of maxillary first molars group(p<0.01). 3. In mandibular molars, the results of probing depth, plaque index, gingival index, mobility are more higher in test group than in control group, and there was a significantly difference(p<0.01). As a result of this study, it can be concluded that, in management of molars with a root fusion, we should detect the molars through the precise radiographic examination, early periodontal treatment and systematic treatment plan should be chosen. And postoperative continuing supportive periodontal therapy is needed.

Light-emitting diode assessment of dentinal defects: the role of presumed extraction forces

  • Coelho, Marcelo Santos;Card, Steven J.;Tawil, Peter Z.
    • Restorative Dentistry and Endodontics
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    • v.42 no.3
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    • pp.232-239
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    • 2017
  • Objectives: The evaluation of iatrogenic dentinal defects in extracted teeth may be influenced by extraction forces and prolonged dry times. The purpose of this study was to compare the presence of dentinal defects in freshly extracted, periodontally compromised teeth with those in a group of teeth with uncontrolled extraction forces and storage time. Materials and Methods: The experimental group consisted of eighteen roots obtained from teeth extracted due to periodontal reasons with class II or III mobility. They were kept in saline and sectioned within 1 hour following extraction. The control group consisted of matched root types obtained from an anonymous tooth collection, consistent with previous dentinal defect studies. The slices were obtained at 3, 6, and 9 mm from the apex. The imaging process exposed all specimens to no more than 60 seconds of dry time. The ${\times}12.8$ magnification was used for the 9 mm slices and ${\times}19.2$ magnification for the 3 mm and 6 mm slices under light-emitting diode (LED) transillumination. The root canal spaces and periodontal tissues were masked to minimize extraneous factors that might influence the evaluators. Chi-square test was used for statistical analysis. Results: Dentinal defects were detected in 17% of the experimental group teeth, compared to 61% of control teeth (p = 0.015). Conclusions: LED transillumination assessment of freshly extracted roots with class II or III mobility showed smaller number of dentinal defects than roots with uncontrolled storage time and extraction forces. The use of freshly extracted roots with mobility should be considered for future dental defect assessment studies.

Development of sound location visualization intelligent control system for using PM hearing impaired users (청각 장애인 PM 이용자를 위한 소리 위치 시각화 지능형 제어 시스템 개발)

  • Yong-Hyeon Jo;Jin Young Choi
    • Convergence Security Journal
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    • v.22 no.2
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    • pp.105-114
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    • 2022
  • This paper is presents an intelligent control system that visualizes the direction of arrival for hearing impaired using personal mobility, and aims to recognize and prevent dangerous situations caused by sound such as alarm sounds and crack sounds on roads. The position estimation method of sound source uses a machine learning classification model characterized by generalized correlated phase transformation based on time difference of arrival. In the experimental environment reproducing the road situations, four classification models learned after extracting learning data according to wind speeds 0km/h, 5.8km/h, 14.2km/h, and 26.4km/h were compared with grid search cross validation, and the Muti-Layer Perceptron(MLP) model with the best performance was applied as the optimal algorithm. When wind occurred, the proposed algorithm showed an average performance improvement of 7.6-11.5% compared to the previous studies.

Evaluation of Performances for Personal Robots

  • Ahn, Chang-hyun;Kim, Jin-Oh;Yi, Keon-Young;Kim, Jin-Oh
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.117.1-117
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    • 2002
  • $\textbullet$ Evaluation techniques of mobility $\textbullet$ Position characteristics $\textbullet$ Path characteristics $\textbullet$ Evaluation techniques of navigation $\textbullet$ Standard measurement environment $\textbullet$ Evaluation program and equipments $\textbullet$ A measurement experiment

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A Study of Whole Body Kinematic Control for a Rescue Robot (구난로봇을 위한 전신 기구학 제어 연구)

  • Hong, Seongil;Lee, Won Suk;Kang, Sin Cheon;Kang, Youn Sik;Park, Yong Woon
    • Journal of the Korea Institute of Military Science and Technology
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    • v.17 no.6
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    • pp.853-860
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    • 2014
  • This paper introduces a Korean rescue robot and presents a whole body kinematic control strategy. The mission of the rescue robot is to move and lift patients or soldiers with impaired mobility in the battlefields, hospitals and hazardous environments. In order for a robot to rescue and assist humans, reliable mobility in various environments, large load carrying capacity, and dextrous manipulability are required. For these objects the robot has variable configuration mobile platform with tracks, dual arm manipulator, and two types of grippers. The electric actuators provide the strength to lift a wounded soldier up to 120 kg using whole body joints. To control the robot with multi degree of freedom, we need to synthesize complex whole-body behaviors, and to manage multiple task primitives systematically. We are to present a whole body kinematic control methodology, and demonstrate its effectiveness through numerical simulations.

The Effect of Thoracic Joint Mobilization on Pain, Proprioception and Static Balance in Patients With Chronic Low Back Pain (흉추 관절가동술이 만성요통환자의 통증, 고유수용감각 및 균형수준에 미치는 효과)

  • Yang, Jin-mo;Kim, Suhn-yeop
    • Physical Therapy Korea
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    • v.22 no.3
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    • pp.1-11
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    • 2015
  • The purpose of this study was to investigate the effect of lumbar stabilization training and additional thoracic mobilization on pain, proprioception and static balance in patients with chronic low back pain. The subjects of this study were 48 chronic low back pain patients who were randomly allocated to an experimental group 1 ($n_1=16$, lumbar stabilization and thoracic mobilization, thoracic hypomobility), experimental group 2 ($n_2=16$, lumbar stabilization and thoracic mobilization, thoracic normal mobility), and a control group ($n_3=16$, lumbar stabilization, thoracic hypomobility) after a thoracic mobility test. Both experimental groups underwent lumbar stabilization training and additional thoracic mobilization. The control group underwent only lumbar stabilization training. The intervention was performed 3 times per week, 30 minutes each time, for a total of 6 weeks. Thoraco-lumbar joint reposition error was measured using an electrogoniometer and static balance ability was measured using the Tetrax posture analysis system. Subjects' pain level was measured using a 100 mm visual analogue scale. Statistical analyses were performed using a one-way analysis of variance and a paired t-test. Post-hoc testing was carried out with a Bonferroni test. The pain level was significantly lower in both experimental groups compared to the control group. Both experimental groups showed significant reductions in joint reposition error angle (flexion, extension, and side bending) compared to the control group. The static balance level was significantly lower in both experimental groups than in the control group. In summary, lumbar stabilization exercises and additional thoracic mobilization significantly improved the pain level, proprioception, and static balance in patients with chronic low back pain.

Threshold Voltage Control of a-Si TFT by Delta Doping of Phosphorous

  • Soh, Hoe-Sup;Kim, Cheol-Se;Kim, Eung-Do
    • 한국정보디스플레이학회:학술대회논문집
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    • 2007.08b
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    • pp.1165-1167
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    • 2007
  • Delta doping method can separate the threshold voltage control region from the charge transport region in a-Si TFT, whereby the threshold voltage of a TFT could be modified. Threshold voltage could be changed by delta doping, while field effect mobility was estimated to be 80% of that of standard TFT.

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Partitioning of Heavy Metals between Rice Plant and Limestone-stabilized Paddy Soil Contaminated with Heavy Metals (석회석을 이용하여 안정화한 중금속오염 논토양에서 토양과 식물체(벼) 간의 중금속 전이특성)

  • Koh, Il-Ha;Kim, Eui-Young;Kwon, Yo Seb;Ji, Won Hyun;Joo, Wanho;Kim, Jinhong;Shin, Bok Su;Chang, Yoon-Young
    • Journal of Soil and Groundwater Environment
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    • v.20 no.4
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    • pp.90-103
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    • 2015
  • The agricultural soil, meets soil environmental standards whereas agricultural product from the same soil does not meet permissible level of contaminants, is identified in the vicinity of the abandoned mine in Korea. This study estimated the stabilization efficiency of Cd and Pb using limestone through the flood pot test for this kind of agricultural paddy soil. We had the concentration of the monitored contaminants in soil solution for 4 months and analyzed fractionations in soil and concentrations in rice plant. In soil solution of plow layer, the reductive Mn had been detected constantly unlike Fe. The concentrations of Mn in limestone amended soil was relatively lower than that in control soil. This reveals that the reductive heavy metals which become soluble under flooded condition can be stabilized by alkali amendment. This also means that Cd and Pb associated with Mn oxides can be precipitated through soil stabilization. Pb concentrations in soil solution of amended conditions were lower than that of control whereas Cd was not detected among all conditions including control. In contaminants fractionation of soil analysis, the decreasing exchangeable fraction and the increasing carbonates fraction were identified in amended soil when compared to control soil at the end of test. These results represent the reduction of contaminants mobility induced by alkali amendment. The Cd and Pb contents of rice grain from amended soil also lower than that of control. These result seems to be influenced by reduction of contaminants mobility represented in the results of soil solution and soil fractionation. Therefore contaminants mobility (phytoavailability) rather than total concentration in soil can be important factor for contaminants transition from soil to agricultural products. Because reduction of heavy metal transition to plant depends on reduction of bioavailability such as soluble fraction in soil.