• Title/Summary/Keyword: Mobility control

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The changes of soil salinity in the Pinus densiflora forest after seawater spread using a fire-fight helicopter

  • Park, Jeong Soo;Koo, Kyu-Sang;Lee, Eun Ju
    • Journal of Ecology and Environment
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    • v.38 no.4
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    • pp.443-450
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    • 2015
  • The east coast of the Korean Peninsula is susceptible to fires because of the low rainfall in winter and spring, and large forest fires have occurred in this area. Lack of fresh water to combat fires has hampered efforts to prevent widespread forest fires in this region. Seawater has not been used as a suppressant because of possible detrimental effects of salt. We investigated the mobility of saline water in the forest soil and their effect on the microbial activity. Using a fire-fighting helicopter, seawater was sprayed over three plots (50 × 100 m) located on the eastern slope of the Baekdu mountain range in South Korea in April, 2011. We sampled the soil in April 4, May 20, and August 5 to determine the amount of salt that remained in the soil. The electrical conductivity value of the soil decreased to <400 μS/cm over a 1-month period. Approximately, four months after the application of seawater, the electrical conductivity value and Na+ content in all treatment plots did not significantly differ to those of the control plot, and total microbial activity also recovered to that of the control. Our results indicate that the amount of rainfall, soil physical-chemical properties, and topological factors may be a critical factor determining the mobility of saline water in forest soil.

A Novel Scheme for Seamless Hand-off in WMNs

  • Vo, Hung Quoc;Kim, Dae-Sun;Hong, Choong-Seon;Lee, Sung-Won;Huh, Eui-Nam
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.3 no.4
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    • pp.399-422
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    • 2009
  • Although current wireless mesh network (WMN) applications experience a perceptually uninterrupted hand-off, their throughput after the hand-off event may be significantly degraded due to the low available bandwidth of the mobile client's new master. In this paper, we propose a novel mobility management scheme for 802.11-based WMNs that enables both seamless hand-off for transparent communications, and bandwidth awareness for stable application performance after the hand-off process. To facilitate this, we (i) present a new buffer moment in support of the fast Layer-2 hand-off mechanism to cut the packet loss incurred in the hand-off process to zero and (ii) design a dynamic admission control to grant joining accepts to mesh clients. We evaluate the benefits and drawbacks of the proposal for both UDP and TCP traffic, as well as the fairness of the proposal. Our results show that the new scheme can not only minimize hand-off latency, but also maintain the current application rates of roaming users by choosing an appropriate new master for joining.

An Efficient Altruistic Looking Protocol for the Mobile Transaction Management System (이동 데이터베이스 시스템을 위한 효율적인 이타적 잠금기법)

  • 권혁신;김세윤;김응모
    • Journal of Information Technology Applications and Management
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    • v.11 no.1
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    • pp.53-67
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    • 2004
  • We propose an advanced transaction scheduling protocol to improve the concurrency and to guarantee the mobility for the mobile database management systems. Mobility, portability, and wireless link In mobile computing environment can cause certain drawbacks, and thus it is more difficult to solve the concurrency control problems. However, a locking scheme should be used to guarantee the data consistency and to prevent the data conflicts. It is well known that data consistency is guaranteed by standard transaction scheduling schemes like two-phase locking (2PL). It has two of operation, lock and unlock. But 2PL does not give solution for mobile system. Altruistic Locking (AL) and classifying transactions, we adapt, can give solution for the previous problems. AL, as an advanced protocol, has attempted to reduce delay effects associated with lock release moment by the use of donation. In this paper, we extend those approaches and classify the transactions to reduce delay effects of short-lived transaction caused by long-lived transaction. In addition, we show efficient solution for the case of disconnection occurrence. Our protocol, namely, Mobile Altruistic Locking (MAL) is shown to be efficiently used in order to reduce delay effects and to guarantee database consistency in a state of the slippery connection in mobile database systems.

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Effects of Geographic Information on the Performance of Multiple Ground Target Tracking System Using Multiple Sensors (다중 센서에 의한 다중 지상 표적 추적시 지형 정보가 미치는 영향)

  • Kim, In-Teak;Lee, Eung-Gi;Kim, Woong-Su
    • Journal of Advanced Navigation Technology
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    • v.2 no.1
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    • pp.43-52
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    • 1998
  • In this paper, we have investigated the effects of geographic information on the performance of multiple ground target tracking system using multiple sensors. Geographic information is utilized in two cases: association and masking target measurement. Virtually no improvement is observed to the overall performance of tracking system when we applied mobility to the association procedure. Masking target measurement based on mobility produces desirable result that the number of false tracks is reduced. Since geographic information can be regarded as an additional sensor in sensor fusion paradigm, careful usage is required.

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Expression of Gal4-VP16 and Gal4-DNA binding domain under the control of the T lymphocyte-specific lck proximal promoter in transgenic mice

  • Ryu, Chun-Jeih;Whitehurst, Charles E.;Chen, Jianzhu
    • BMB Reports
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    • v.41 no.8
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    • pp.575-580
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    • 2008
  • Thymocyte-specific transcriptional regulatory systems can be used to better understand the relationship between transcription and V(D)J recombination during early T cell development. In this study, we generated transgenic mice expressing the transactivator Gal4-VP16 or the Gal4 DNA binding domain (Gal4-DBD) under the control of the lck proximal promoter, which is only active in immature thymocytes. From these studies Gal4-VP16 and Gal4-DBD expression was shown to significantly alter thymic cellularity and differentiation without significantly changing the $CD3^+$ thymocyte distribution. Furthermore, the presence of Gal4-VP16 or Gal4-DBD in the transgenic thymocytes retarded the mobility of the Gal4 DNA binding motif as determined by a gel mobility shift assay, suggesting that the developmental alteration did not affect the functional property of the transgenic proteins. These results indicated that lck promoter-driven Gal4-VP16 or Gal4-DBD expression did not affect $CD3^+$ mature thymocytes, thus this system can be applied to study transcriptional regulation of transresponder genes in bigenic mouse model thymocytes.

The Method of Vertical Obstacle Negotiation Inspired from a Centipede (지네를 모방한 수직 장애물 극복방법)

  • Yoon, Byung-Ho;Chung, Tae-Il;Koh, Doo-Yeol;Kim, Soo-Hyun
    • Journal of Institute of Control, Robotics and Systems
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    • v.18 no.3
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    • pp.193-200
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    • 2012
  • Mobility is one of the most important issues for search and rescue robots. To increase mobility for small size robot we have focused on the mechanism and algorithm inspired from centipede. In spite of small size, using many legs and flexible long body, centipede can overcome high obstacles and move in rough terrains stably. This research focused on those points and imitated their legs and body that are good for obstacle negotiation. Based on similarity of a centipede's legs and tracks, serially connected tracks are used for climbing obstacles higher than the robot's height. And a centipede perceives environments using antennae on its head instead of eyes. Inspired from that, 3 IR sensors are attached on the front, top and bottom of the first module to imitate the antenna. Using the information gotten from the sensors, the robot decides next behavior automatically. In experiments, the robot can climb up to 45 cm height vertical wall and it is 600 % of the robot's height and 58 % of the robot's length.

Relationship between the Self-Reported Oral Health Status and Hemoglobin A1c Level among Diabetic Patients (일부 당뇨병 환자에서 당화혈색소 수치와 주관적 구강건강상태와의 연관성)

  • Choi, Jun-Seon
    • Korean Journal of Health Education and Promotion
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    • v.25 no.1
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    • pp.55-69
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    • 2008
  • Objective: This study was to investigate the relationship between hemoglobin A1c level and self-reported oral health status. Methods: The subjects of this study were 150 diabetic patients (60 male patients and 90 female patients) who went to the internal and family medicine departments of clinic. This study used the questionnaire and NYCOCARD$\square$ READERII to quantify hemoglobin A1c. Results: The proportion of well controlled diabetes subjects was 31.3%. When hemoglobin A1c levels became higher, subjects perceived that there were more decay teeth, bleeding, swollen gums, mobility teeth, and oral disease symptoms. In comparison with the well glycemic control group, poor glycemic control group perceived that the overall oral health status was worse, and had more bleeding teeth, swollen gums and mobility teeth. Conclusion: These results show that hemoglobin A1c level is related to the self-reported oral health status. Therefore, dental professionals should emphasize more the necessity of maintaining the hemoglobin A1c of normal range and monitoring it periodically, and the practice of thorough oral hygiene care in order to promote diabetic patients' oral health.

Durable Distance Vector Multicasting Protocol for Mobile Ad hoc Networks Based on Path-Durability (이동 애드혹 네트워크를 위한 경로 지속성을 고려한 거리벡터 멀티케스트 프로토콜)

  • Lee, Se-Young;Chang, Hyeong-Soo
    • Journal of KIISE:Information Networking
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    • v.33 no.6
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    • pp.461-472
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    • 2006
  • In this paper, we propose a novel on-demand multicasting algorithm, 'Durable Distance Vector Multicasting(DDVM),' for Mobile Ad hoc Network(MANET). DDVM has a more efficient routing-control complexity than Link State Routing(LSR) and with the smaller complexity, DDVM provides a high delivery ratio for MANET with high mobility by adapting to dynamic topological changes. This is achieved by adding 'combined path durability' statistic into the routing-control information of Distance Vector Routing(DVR). The routing-path duration statistic is computed in a fully distributed manlier at each node in the network based on only local information from neighbour nodes. We show by simulation studies the effectiveness of DDVM compared with On-demand Multicast Routing Protocol(ODMRP).

Effects of the Functional Movement Correction Exercise on the Functional Movement Screen Scores of Badminton Players (기능성 움직임 교정운동이 배드민턴 선수의 Functional Movement Screen 점수에 미치는 효과)

  • Kim, Tae-Yoon;Kim, Seok-Hwan
    • PNF and Movement
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    • v.15 no.1
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    • pp.67-75
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    • 2017
  • Purpose: The purpose of this study was to determine the effects of a functional movement correction exercise on the functional movement screen scores of badminton players. Methods: The participants consisted of 25 badminton players who were randomly assigned to an experimental group (n = 13) or a control group (n = 12); they engaged in exercise three times per week for eight weeks. The experimental group engaged in the functional movement correction exercise, while the control group engaged in general exercise. An FMS kit (USA) was used to measure the following: FMS score, deep squat, hurdle step, in-line lunge, shoulder mobility, active straight leg raise, trunk stability push up, and rotary stability. Results: The FMS score, deep squat, hurdle step, in-line lunge, shoulder mobility, active straight leg raise, and trunk stability push up, and rotary stability showed significant improvement in the experimental group (p < 0.05). Conclusion: The experiment confirmed that the functional movement screen scores of badminton players improve with effective exercise interventions.

Autonomous Navigation Power Wheelchair Using Distance Measurement Sensors and Fuzzy Control (거리측정 센서 스캐닝과 퍼지 제어를 이용한 전동 휠체어 자율주행 시스템)

  • Kim, Kuk-Se;Yang, Sang-Gi;Rasheed, M. Tahir;Ahn, Seong-Soo;Lee, Joon
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2008.05a
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    • pp.329-336
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    • 2008
  • Nowadays with advancement in technology and aging society, the number of disabled citizens is increasing. The disabled citizens always need a caretaker for daily life routines especially for mobility. In future, the need is considered to increase more. To reduce the burden from the disabled, various devices for healthcare are introduced using computer technology. The power wheelchair is an important and convenient mobility device. The demand of power wheelchair is increasing for assistance in mobility. In this paper we proposed a robotic wheelchair for mobility aid to reduce the burden from the disabled. The main issue in an autonomous wheelchair is the automatic detection and avoidance of obstacles and going to the pre-designated place. The proposed algorithm detects the obstacles and avoids them to drive the wheelchair to the desired place safely. By this way, the disabled will not always have to worry about paying deep attention to the surroundings and his path.

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