• 제목/요약/키워드: physical mechanism

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배수혈의 내장기 치료 기전에 관한 연구 (Study on the Treatment Mechanism of Back-Shu Points for Organ Dysfunction)

  • 황만석
    • Korean Journal of Acupuncture
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    • 제33권3호
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    • pp.95-101
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    • 2016
  • Objectives : This study aims to overview the therapeutic mechanism of back-shu points in terms of sympathetic visceral motor nervous system. Methods : Studies about autonomic nervous system, and studies and ancient texts about back-shu points were reviewed. We interpreted possible mechanism of back-shu points considering similarities of anatomical and physiological characteristics of back-shu points and visceral motor nervous system. Results : Afferent signals for organ lesions that can develop the symptoms of autonomic neurological symptoms, pain, hyperalgesia through the skin segment. Through a physical examination of the myotome and dermatome, it is possible to diagnose segmental disorders. Treatment stimulation of the thick fibers of the disorder segment skin can reduce abnormal autonomic influence over the sympathetic reflex mechanism. In addition, if spinal muscles are relaxed, the pressure on the nerve roots could be reduced and consequently the hyperactivity of the sympathetic visceral motor signal would be suppressed. Conclusions : The back-shu points treatments work through the mechanism of the sympathetic nervous reflex. Moreover, segmental acupuncture can reduce tension of the spinal muscles, thereby improving pathological conditions of the sympathetic nervous system.

SenSation : A New Translational 2 DOF Haptic Device with Parallel Mechanism

  • Chung, Young-Hoon;Lee, Jae-Won
    • Transactions on Control, Automation and Systems Engineering
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    • 제3권4호
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    • pp.217-222
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    • 2001
  • We propose a new two-degree of freedom parallel mechanism for a haptic device and will refer to the mechanism as the SenSation. The SenSation is designed in order to improve the kinematic performanced and to achieve static balance. We use the panto graph mechanisms in order to change the location of active joints, which leads to transform a direct kinematic singularity into a nonsingularity. The direct kinematic singular configurations of the SenSation occur near the workspace boundary. Using the property that position vector of rigid body rotating about a fixed point is normal to the velocity vector, Jacobian matrix is derived. Using the vector method, two different types of singularities of the SenSation can be identified and we discuss the physical significance of each of the three types of singularities. We will compare the kinematic performances(force manipulability ellipsoid, kinematic isotropy) of the SenSation with those of five-var parallel mechanism. By specifying that the potential energy be fixed, the conditions for the static balancing of the SenSation is derived. The static balancing is accomplished by changing the center of mass of the links.

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공유 메모리 버퍼에서의 예방적 적응 한계치 버퍼 할당 기법 (Preventive Adaption Threshold Mechanism in Buffer Allocation for Shared Memory Buffer)

  • 신태호;이성창;이형호
    • 대한전자공학회논문지TC
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    • 제38권10호
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    • pp.24-33
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    • 2001
  • 패킷 통신에 있어서 주요 서비스 품질(QoS : Quality of Service) 요소로는 지연(delay), 지연 변이(delay variation), 패킷 손실율(loss rate) 등이 있다. 본 논문에서는 복수의 논리적 버퍼가 하나의 메모리 버퍼를 공유할 때, 논리버퍼의 손실율 성능을 향상시키기 위한 새로운 버퍼 할당 기법을 제안한다. 제안된 예방적 적응 한계치(PAT : Preventive Adaption Threshold) 버퍼 할당 기법은 기존의 동적 한계치 (Dynamic Threshold)기법에서 사용하는 패킷 폐기 한계치(threshold)의 직선적 변화 궤적과는 다른 한계치 동적 변화 궤적을 사용함으로써 패킷 손실율 성능을 개선하였다. 제안된 기법의 성능을 평가하기 위하여 기존의 무제어(NC : No Control), 고정 한계치(ST : Static Threshold), 동적 한계치(DT : Dynamic Threshold)등의 기법과 여러 측면에서 손실율 성능을 비교하였다.

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트러스 구조를 기반으로 한 로봇 발 메커니즘 모델링 및 특성 분석 (Modeling and Analysis of Robotic Foot Mechanism Based on Truss Structure)

  • 김병호
    • 한국지능시스템학회논문지
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    • 제22권3호
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    • pp.347-352
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    • 2012
  • 본 논문에서는 보행 로봇을위한 트러스 구조의 로봇 발 메커니즘을 제시한 후, 제시된 로봇 발 메커니즘의 특성을 분석하였다. 제시된 로봇 발 메커니즘은인간의 발의 구조적인 특징을 관찰하여 모델링 되었다. 특히, 인간의 발에 사용되고 있는 뼈대는 트러스로 나타내었고, 뼈대에 연결되어 있는 다양한 인대는 간단한 강성 요소로서 나타내었다. 따라서 이러한 로봇 발은 보행 로봇이 발걸음을 옮기는 과정에서 발에 작용되는 충격을 완화시킬 수 있는 장점을 갖는다. 결과적으로, 제안된 로봇 발 메커니즘은 보행로봇의 보행피로를 줄이는데 기여할 수 있다.

Microscopic damping mechanism of micro-porous metal films

  • Du, Guangyu;Tan, Zhen;Li, Zhuolong;Liu, Kun;Lin, Zeng;Ba, Yaoshuai;Ba, Dechun
    • Current Applied Physics
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    • 제18권11호
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    • pp.1388-1392
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    • 2018
  • Metal thin films are used widely to solve the vibration problem. However, damping mechanism is still not clear, which limits the further improvement of the damping properties for film and the development of multi-functional damping coating. In this paper, Damping microscopic mechanism of porous metal films was investigated at both macroscopically and microscopically mixed levels. Molecular dynamics simulation method was used to model and simulate the loading-unloading numerical experiment on the micro-pore and vacancy model to get the stress-strain curve and the microstructure diagram of different defects. And damping factor was calculated by the stress-strain curve. The results show that dislocations and new vacancies appear in the micro-pores when metal film is stretched. The energetic consumption from the motion of dislocation is the main reason for the damping properties of materials. Micro-mechanism of damping properties is discussed with the results of in-situ experiment.

A Novel Electronic Voting Mechanism Based on Blockchain Technology

  • Chuan-Hao, Yang;Pin-Chang Su;Tai-Chang Su
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제17권10호
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    • pp.2862-2882
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    • 2023
  • With the development of networking technology, it has become common to use various types of network services to replace physical ones. Among all such services, electronic voting is one example that tends to be popularized in many countries. However, due to certain concerns regarding information security, traditional paper voting mechanisms are still widely adopted in large-scale elections. This study utilizes blockchain technology to design a novel electronic voting mechanism. Relying on the transparency, decentralization, and verifiability of the blockchain, it becomes possible to remove the reliance on trusted third parties and also to enhance the level of trust of voters in the mechanism. Besides, the mechanism of blind signature with its complexity as difficult as solving an elliptic curve discrete logarithmic problem is adopted to strengthen the features related to the security of electronic voting. Last but not least, the mechanism of self-certification is incorporated to substitute the centralized certificate authority. Therefore, the voters can generate the public/private keys by themselves to mitigate the possible risks of impersonation by the certificate authority (i.e., a trusted third party). The BAN logic analysis and the investigation for several key security features are conducted to verify that such a design is sufficiently secure. Since it is expected to raise the level of trust of voters in electronic voting, extra costs for re-verifying the results due to distrust will therefore be reduced.

Mouse Air Pouch Model에서 침전극 저주파치료로 유도된 소염 작용에 관한 연구 (Study for Related Mechanism of Anti-Inflammatory Effect Induced by Neddle electrode electrical stimulation in Mouse Air Pouch Model.)

  • 정진우;황현숙;임종수
    • 대한물리치료과학회지
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    • 제9권2호
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    • pp.111-122
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    • 2002
  • In oriental medicine, manual-acupuncture and electroacupuncture (EA) have been widely utilized to cure several inflammatory diseases such as arthritis. We designed this experiment to find neurochemical mechanism related to electroacupuncture induced anti-inflammatory effect on mouse air pouch model. EA with both low frequency (1 Hz) and high frequency (120 Hz) was treated after induction of inflammation in air pouch using injection of zymosan. To verify the role of opioid system in electroacupuncture-induced anti-inflammatory effect, naloxone (10 mg/kg) was pretreated. In addition, idazoxan (5 mg/kg) was pre-treated to evaluate the possible effect of endogenous adrenergic system in autonomic system on EA induced anti-inflammatory effect. As results of this study, naloxone pretreatment did not change the anti-inflammatory effect evoked by high frequency EA, while low frequency EA(1 Hz) induced anti-inflammatory effect was dramatically suppressed by naloxone pretreatment. These data indicated that endogenous opioid system might be extensively involve in anti-inflammatory effect evoked by not high frequency, but low frequency EA. However, idazoxan pretreatment did not produce any modulatory effect on both low and high frequency EA induced anti-inflammatory effect, suggesting that EA induced anti-inflammatory effect was not mediated by endogenous adrenergic system. In conclusion, these data strongly suggested that EA induced anti-inflammatory effect is mediated by endogenous opioid system, not endogenous adrenergic system.

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과훈련 증후군의 기전 및 뇌 신경전달물질과 신경조절물질의 역할 (The Mechanism of Overtraining Syndrome and the Role of Brain Neurotransmitters and Neuromodulators)

  • 김한철;김우철;김성운
    • 한국융합학회논문지
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    • 제8권11호
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    • pp.461-476
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    • 2017
  • 본 연구의 목적은 과훈련 증후군과 관련된 기존의 이론을 살펴보고, 새로운 접근인 과훈련 증후군 및 뇌신경전달물질과 신경조절물질 간의 역할과 관련된 국내외 문헌들을 고찰하여 스포츠 지도자와 선수들에게 뇌 과학적 관점에서 과훈련 증후군에 대한 이해도를 높일 수 있는 기초자료를 제공하는데 있다. 본 연구결과 과훈련 증후군에 대한 많은 가설들이 제안되었으며, 각각 강점과 약점이 있었다. 그리고 뇌신경 전달 물질인 세로토닌의 농도가 증가 할 때 발생하는 유사한 증상이 과훈련 증후군의 신호와 증상과 관련성이 있는 것으로 나타났다. 하지만 중추신경 또는 말초신경 그 어느 곳에서 매개되는지에 대한 기전을 구별 할 수 없기 때문에 현재까지는 검증 할 수 없었다. 따라서 과훈련 증후군의 기전을 기존의 이론 및 뇌 신경전달물질과 신경조절물질의 상호작용을 통해 알아본 본 연구는 스포츠 현장에서 활동하고 있는 지도자와 선수들에게 과훈련 증후군의 복잡한 원인을 이해시키는데 매우 중요한 기초정보를 제공할 것이라고 판단된다. 물론 지금까지는 과훈련 증후군 기전 및 뇌 신경전달물질과 신경조절물질 간의 연관성에 관한 연구가 많이 부족했지만 본 연구를 통해 조금이나마 더 많은 사람들이 과훈련 증후군에 대한 이해의 폭을 넓히는 계기가 되기를 기대한다.

근육긴장도와 이에 영향을 미치는 체성감각계에 관한 고찰 (Muscle Tone and Somatosensory System acting on This)

  • 김중휘;권용현;박정미;김중선
    • The Journal of Korean Physical Therapy
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    • 제15권2호
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    • pp.85-99
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    • 2003
  • Muscle tone is the force with which a muscle resists being lengthened. Muscle tone is often tested clinically by passively extending and flexing a relaxed patient's limbs and feeling the resistance offered by the muscle. Both nonneural and neural mechanism contribute to muscle tone. Muscle tone is the mechanisms that contribute to the generation of tone in individual muscles when a person is in a relaxed state. This background level of activity changes in a certain antigravity posture muscle when we stand upright, thus counteracting the force of gravity. This increased level of activity in antigravity muscles is known as postural tone. The evidence from experiments showing that lesions of the dorsal(sensory) roots of the spinal cord reduced muscle(postural) tone is influenced by inputs from the somatosensory system. Patients with neurological damage have several state of muscle(postural) tone, which display from flaccidity to rigidity. This review article deal with muscle tone and somatosensory system acting on this. The understanding about this contribute to a better therapeutic approach for the rehabilitation of patients to have an abnormal muscle(postural) tone due to neurological damage.

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체간에 무게 부하를 적용한 정상 성인의 보행 분석 (Gait analysis of Healthy Adults with External Loads on Trunk)

  • 장종성;최진호;이미영;김명권
    • 대한물리의학회지
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    • 제7권1호
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    • pp.69-75
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    • 2012
  • Purpose : The study was designed to investigate analysis of kinematics of lower extremity in healthy adults during walking with external loads on trunk. Methods : Fifteen healthy adults were recruited and The subjects provided written and informed consent prior to participation. They walked on a ten-meter walkway at a self-selected pace with loads of 0, 5, 10, and 15kg. They completed three trials in each condition and kinematic changes were measured. A three-dimensional motion analysis system was used to analyze lower extremity kinematic data. The data collected by each way of walking task and analyzed by One-way ANOVA. Results : There were significant differences in hip and knee joint on saggittal plane at initial contact and preswing, and significant differences in ankle joint on transverse plane at preswing. Conclusion : These findings revealed that increased external loads were changed joint angles and influenced postural strategies because of kinematic mechanism and future studies is recommended to find out prevention from damage of activities of daily living.