• Title/Summary/Keyword: dynamic recovery

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Improved Performance of Permanent Magnet Synchronous Motor by using Particle Swarm Optimization Techniques

  • Elwer, A.S.;Wahsh, S.A.
    • Journal of Power Electronics
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    • v.9 no.2
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    • pp.207-214
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    • 2009
  • This paper presents a modem approach for speed control of a PMSM using the Particle Swarm Optimization (PSO) algorithm to optimize the parameters of the PI-Controller. The overall system simulated under various operating conditions and an experimental setup is prepared. The use of PSO as an optimization algorithm makes the drive robust, with faster dynamic response, higher accuracy and insensitive to load variation. Comparison between different controllers is achieved, using a PI controller which is tuned by two methods, firstly manually and secondly using the PSO technique. The system is tested under variable operating conditions. Implementation of the experimental setup is done. The simulation results show good dynamic response with fast recovery time and good agreement with experimental controller.

A Study of the Control Logic Development of Driveability Improvement in Vehicle Acceleration Mode (차량 급가속시 운전성 향상을 위한 제어로직 개선에 관한 연구)

  • 최윤준;송해박;이종화;조한승;조남효
    • Transactions of the Korean Society of Automotive Engineers
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    • v.10 no.2
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    • pp.101-116
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    • 2002
  • Modern vehicles require a high degree of refinement, including good driveability to meet customer demands. Vehicle driveability, which becomes a key decisive factor for marketability, is affected by many parameters such as engine control and the dynamic characteristics in drive lines. Therefore, Engine and drive train characteristics should be considered to achieve a well balanced vehicle response simultaneously. This paper describes analysis procedures using a mathematical model which has been developed to simulate spark timing control logic. Inertia mass moment, stiffness and damping coefficient of engine and drive train were simulated to analyze the effect of parameters which were related vehicle dynamic behavior. Inertia mass moment of engine and stiffness of drive line were shown key factors for the shuffle characteristics. It was found that torque increase rate, torque reduction rate and torque recovery timing and rate influenced the shuffle characteristics at the tip-in condition for the given system in this study.

A Study and Investigation on the Influence of Static and Dynamic Loading on the Properties of Handmade Persian Carpet (I) - The Effect of Static Loading -

  • Mirjalili S. A.;Sharzehee M.
    • Fibers and Polymers
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    • v.6 no.2
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    • pp.139-145
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    • 2005
  • The paper reports the physical and mechanical properties of hand-woven carpets, which have been put under static force. Two groups of wool fibres, from two parts of Iran, were prepared to spin pile yams for the carpets. Each group of the fibres included both conventional and tanned wool. Then two yam counts, $N_m$ = 4/2 and 6/2, were spun for two different knot densities. After weaving the carpets, they were put under static force and their thickness variations were measured and plotted against time, in logarithm scale. The resiliency of the carpets piles after eliminating the static force, were measured and plotted against time, in logarithm scale, too. The results were compared to each other and analysed with respect to parameters such as the type and quality of the wool fibres as well as knot density of the carpets.

Large enhancement in mechanical properties of the 5052 Al alloys by cryogenic and warm rolling (극저온 압연 및 온간 압연 기술을 이용한 5052 알루미늄 합금의 기계적 성질의 향상)

  • Gang, E.G.;Lee, S.H.;Lee, J.C.;Nam, W.J.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2007.10a
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    • pp.81-83
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    • 2007
  • Cryogenic rolling combined with warm rolling has been found to be more effective than only cryogenic rolling procedure in improving the strength of a 5052 Al alloy. In this study, cryo-rolled 5052 Al alloys were aged at $175^{\circ}C$. Warm rolling was conducted after dipping plates into silicon oil bath. A notable increase of tensile strength is achieved by the precipitation during warm rolling. The mechanical behavior of this alloy was investigated by hardness and tensile tests. The microstructure was investigated by transmission electron microscopy. It was found that the cryogenic rolling combined with warm rolling was very effective in improving tensile strength.

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Heating Power Consumption Comparison Study Between Static Insulation and Dynamic Insulation at KIER Twin Test Cell (동적 단열재를 적용한 건물에서의 에너지소비량 비교 분석)

  • Kang, Eun-Chul;Park, Yong-Dai;Lee, Euy-Joon;Yun, Tae-Kwon
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.919-924
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    • 2008
  • Power consumption in the building thermal load could be the sum of the building fabric conduction load, building ventilation convection load and other such as radiation loss load. Dynamic Breathing Building (DBB) is the state-of-the-art to improve the wall insulation and indoor air quality(IAQ) performance as making air flow through the wall. This heat recovery type DBB contributes the power consumption saving due to the improved dynamic U-value. KIER twin test cell with static insulation(SI) and dynamic insulation(DI) at KIER was developed to test building power consumption at the real outside conditions. Then, the actual results were compared with the theory to predict the power consumption at the KIER twin test cell and introduced the building new radiation loss factor $\alpha$ to explain the difference between the both the theory and the actual case. As the results, the power consumption at the breathing DI wall building could saved 10.8% at the 2ACH(Air change per hour) compared with conventional insulation. The building radiation loss factor $\alpha$ for this test condition to calibrate the actual test was 0.55 in the test condition.

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Effect of Muscle Taping and Joint Taping on Static and Dynamic Balance in Normal Adults with Chronic Ankle Instability

  • Kim, Hyun-Sung;Park, Jae-Young
    • Journal of The Korean Society of Integrative Medicine
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    • v.10 no.1
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    • pp.101-108
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    • 2022
  • Purpose : This study was conducted to investigate the effect of muscle taping and joint taping on static and dynamic balance in normal adults with chronic ankle instability. Methods : The subjects of this study were 32 people who met the inclusion criteria. This cross-sectional study was conducted using the Kinesio tape, an elastic tape, was used. Subjects were randomized to exclude the effect of sequence, and no taping, joint taping, and muscle taping were applied as taping interventions. One-leg standing test and a Functional reach test were conducted to measure static balance, and Y-balance test was conducted to measure dynamic balance. One way repeated ANOVA was performed to investigate the difference in balance ability according to the taping intervention. If there was a significant difference, a post-hoc was performed using the Bonferroni method. Results : In the case of static balance, joint taping showed more significant results than did no taping and muscle taping (p<.05), and muscle taping showed more significant results than did no taping (p<.05). In the case of dynamic balance, muscle taping showed significantly larger results than did no taping and joint taping (p<.05) and joint taping showed significantly larger results than did no taping (p<.05). Conclusion : This study found that mechanical stimulation of muscles and joint compression by elastic taping increased ankle stability and improved static and dynamic balance. In particular, for static balance, joint taping was more effective than muscle taping, and for dynamic balance, muscle taping was more effective than joint taping. Applying the appropriate taping method to individual subjects has the advantage of maximizing the therapeutic effect for the recovery of balance ability. Similarly, the application of various tapings to subjects with ankle instability will have a positive effect on functional improvement.

Proactive Data Dissemination Protocol on Distributed Dynamic Sink Mobility Management in Sensor Networks (센서 네트워크에서 다수의 이동 싱크로의 에너지 효율적인 데이터 전파에 관한 연구)

  • Hwang Kwang-Il;Eom Doo-Seop;Hur Kyeong
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.9B
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    • pp.792-802
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    • 2006
  • In this paper, we propose an energy-efficient proactive data dissemination protocol with relatively low delay to cope well with highly mobile sink environments in sensor networks. In order for a dissemination tree to continuously pursue a dynamic sink, we exploit two novel algorithms: forward sink advertisement and distributed fast recovery. In our protocol, the tree is shared with the other slave sinks so that we call it Dynamic Shared Tree (DST) protocol. DST can conserve considerable amount of energy despite maintaining robust connection from all sources to sinks, since tree maintenance of DST is accomplished by just distributed local exchanges. In addition, since the DST is a kindof sink-oriented tree, each source on the DST disseminates data with lower delay along the tree and it also facilitates in-network processing. Through simulations, it is shown that the presented DST is considerably energy-efficient, robust protocol with low delay compared to Directed Diffusion, TTDD, and SEAD, in highly mobile sink environment.

A Migration Technique for Autonomous Mobile Agents in Dynamic Environments (동적 환경에 적합한 자율 이동 에이전트의 이주 기법)

  • Bok, Kyoung-Soo;Yeo, Myung-Ho;Yoo, Jae-Soo
    • Journal of KIISE:Software and Applications
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    • v.32 no.11
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    • pp.1084-1098
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    • 2005
  • In this paper, we propose a migration technique for autonomous mobile agents suitable to dynamic environments. The proposed migration technique dynamically creates the itinerary of agents that considers states of networks and systems. In the migration of the agent, it first sends prefetching message to the next system. The system receives necessary data for migration in advance. Through this, we reduce the amount of the sending data and save the time for creating the instance of the agent. And it improves the execution efficiency by using the checkpoint-based recovery method that does not execute the agent again and recovers the process states even though the errors take place. To show superiority of the proposed technique, we compare the proposed method with the existing methods through various simulations.

Effect on Balance Ability of Knee Osteoarthritis by Lower Extremity Patterns with dynamic reverse in Proprioceptive Neuromuscular Facilitation (PNF 하지 패턴 중 동적반전(dynamic reverse) 기법이 퇴행성 슬관절염 환자의 균형능력에 미치는 영향)

  • Jung, Hyun-Sung;Jeon, Ho-Young;Bae, Sung-Soo
    • PNF and Movement
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    • v.4 no.1
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    • pp.27-36
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    • 2006
  • Purpose : The main purpose of this study was to investigate the effect on Balance Ability of Knee Osteoarthritis(OA) by Lower Extremity Patterns with dynamic reverse in Proprioceptive Neuromuscular Facilitation(PNF). Methods : The subjects were consisted of 30 women patients with knee OA. All subjects were randomly assigned to PNF group. Each group had a treatment for 30 minutes per day and three times a week during 8 weeks period. Was used to measure recovery or worse of patient's condition, muscle assessment questionnaire(MAQ) was used to measure patient' s muscular strength, Endurance, coordination/balance, KWOMAC was used to pain, stiffness, and physical function, and BPM was used to measure path, anterior-posterior. Results : This study results in following conclusons. 1. MAQ score was significantly decreased in PNF group(p<.05). 2. KWOMAC score was significantly decreased in PNF group(p<.05). 3. BPM were score was significantly decreased in PNF group(p>.05). Conclusion : From this result the PNF treatment retrogression characteristic will be effective in treatment of patient, with the arthritis and widely may be applied at a therapist.

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A mathematical model to recover missing monitoring data of foundation pit

  • Liu, Jiangang;Zhou, Dongdong;Liu, Kewen
    • Geomechanics and Engineering
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    • v.9 no.3
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    • pp.275-286
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    • 2015
  • A new method is presented to recover missing deformation data of lateral walls of foundation pit when the monitoring is interrupted; the method is called Dynamic Mathematical Model - Parameter Interpolation. The deformation of lateral walls of foundation pit is mainly affected by the type of supporting structure and the situation of constraints, therefore, this paper mainly studies the two different kinds of variation law of deep horizontal displacement when the lateral walls are constrained or not, proposes two dynamic curve models of normal distribution type and logarithmic type, deals with model parameters by interpolating and obtains the parameters of missing data, then missing monitoring data could be Figured out by these parameters. Compared with the result from the common average method which is used to recover missing data, in the upper 2/3 of the inclinometer tube, the result by using this method is closer to the actual monitoring data, in the lower 1/3 part of the inclinometer tube, the result from the common average method is closer to the actual monitoring data.