• Title/Summary/Keyword: fixed-intensity

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Effects of Fixed-intensity and Varied-intensity Electroacupuncture in Pain and Sensory Threshold in Patients with Chronic Tension Headache (전침 자극 강도에 따른 만성 긴장성 두통 환자의 통증과 감각역치 변화 연구)

  • Kwon, You-Jung;Lee, Dong-Hua;Lee, Ung-In;Park, Kyung-Mo;Lee, Sang-Hoon
    • Journal of Acupuncture Research
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    • v.29 no.4
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    • pp.25-34
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    • 2012
  • Objectives : This study was conducted to investigate the effects of fixed-intensity and varied-intensity electroacupuncture in pain and sensory threshold concerning parameters visual analogue scale(VAS), brief pain inventory(BPI) and quantitative sensory testing(QST), among chronic tension headache patients. Methods : Thirty patients with chronic tension headache were randomly assigned to three groups and received different kinds of electroacupuncture at $ST_{36}$ and $ST_{37}$. Group A received fixed-intensity electroacupuncture(fixed-EA), group B received varied-intensity electroacupuncture (varied-EA), and group C received only acupuncture treatment without electrical stimulation as a control group. The intervention was given three times per week, and continued in two weeks. All the experiments were conducted blindly. Results : Fixed-EA group showed a significant decrease of VAS and BPI compared to the baseline measurement, while both varied-EA and control group did not. Of the parameters of QST, subtraction of heat pain threshold(HPT) and cold pain threshold(CPT) slightly increased in all groups, but this was not significant. Conclusions : These results suggest that fixed-EA reduce pain and improve quality of life in patients with chronic tension headache and that acupuncture may regulate patient's pain sensitivity through changing sensory threshold.

Effects of Fixed-intensity and Varied-intensity Electroacupuncture on Heart Rate Variability in Healthy People with Stress Task (고정자극 전침과 변동자극 전침의 정상인 스트레스에 대한 심박변이도 변화 연구)

  • Lim, Sung-Keun;Lee, Dong-Hua;Kwon, You-Jung;Lee, Jeung-Chan;Jung, Chang-Jin;Kim, Yong-Suk;Park, Kyung-Mo;Lee, Sang-Hoon
    • Journal of Acupuncture Research
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    • v.28 no.2
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    • pp.107-116
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    • 2011
  • Objectives : This study was performed to investigate the effects of fixed-intensity and varied-intensity electroacupuncture on heart rate variability in healthy people with stress task. Methods : Forty healthy subjects were randomly assigned to either group A or group B or C. Group A received fixed-intensity electroacupuncture(F-EA) at $ST_{36}$ and $ST_{37}$. After 1 week wash out period to prevent overlapping residual effects, they received varied-intensity electroacupuncture(V-EA) in which the intensity was changed every two minutes based on individual heart rate variability at the same points. Group B received the treatments in reverse order. Group C received no intervention as a control group. Results : Control group showed a significant increase of LF and LF/HF during the 2nd working memory task, while both F-EA and V-EA did not. In addition, V-EA showed a significant increase of HF during 2nd rest while F-EA did not. Conclusions : These results suggest that F-EA and V-EA can inhibit sympathetic activation more than control group and that V-EA can enhance parasympathetic activation more than F-EA.

A Study on the fracture Mechanical Behavior of Cruciform Welded Joint With Fracture Cracks (십자형 필렛 용접 이음의 피로균열 에 대한 파괴 역학적 고찰)

  • 엄동석;강성원;유덕상
    • Journal of Welding and Joining
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    • v.1 no.1
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    • pp.37-46
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    • 1983
  • This paper describes a study of fillet welded joint stressed perpendicular to the weld line. The finite element method was used to determine the stress intensity factor for cruciform joint at weld toe and root cracks according to variation of H/Tp, weld angle and main plate thickness. But, in this study, weld angle was fixed at 45.deg., since the variation of weld angle affect the stress intensity factor little, also main plate thickness was fixed. Pulsating tension fatigue test was done at the second phase of experiment. The work using the concepts of the fracture mechanics on the stable crack growth, was in the correlation of the experimental fatigue stress-life behavior because the fatigue behaviors of various joint geometries are related to the stress intensity factors calculated by F.E.M. analysis. Main results obtained are summarized as follows. 1) According to the propagation of toe crack, the variation of the stress intensity factor at root crack is obvious as H/Tp is smaller. 2) According to the propagation of root cracks, the change of the stress intensity factor of the toe is very large with propagation of root crack. 3) The calculation formula of the stress intensity factor of crack propagation at the root crack was obtained. 4) The calculation formula of the stress intensity factor at the toe cracks was obtained in similar manner. 5) From the results of experiment, the velocity of fatigue crack propagation at the weld toe and root was estimated.

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Finite Element Analysis of Subsurface Crack Propagation in Half-space Due to Sliding Contact (유한요소법을 이용한 미끄럼 접촉시의 반무한체 내의 수평균열 전파해석)

  • 이상윤;김석삼
    • Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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    • 1999.06a
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    • pp.297-302
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    • 1999
  • Finite element analysis is peformed about the crack propagation in half-space due to sliding contact. The analysis is based on linear elastic fracture mechanics and stress intensity factor concept. The crack location is fixed and the friction coefficient between asperity and half-space is varied to analyze the effect of surface friction on stress Intensity factor for horizontal crack. The crack propagation direction is predicted based on the maximum range of shear and tensile stress intensity factor.

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The Decision Algorithm for Driving Intension Using Moduled Neural Network (모듈화된 신경망을 이용한 운전의지 판단 알고리즘)

  • 강준영;김성주;김용택;서재용;전홍태
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2001.12a
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    • pp.271-274
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    • 2001
  • Recently, most vehicles has the Automatic transmission system as their transmission system. The automatic transmission system operates with fixed shift patterns. In the opposite of manual operation, it is easy and convenient for driving. Though these merit, the system can not evaluate the driver's intension because of usage of fixed shift pattern, To consider driver's intension, we must consider both the driving intensity of driver and the status of vehicle. In this paper, we developed flexible automatic transmission system by using the proposed moduled neural networks which can learn the status of the vehicle and driver's intensity As a result, we compare the transmission system using fixed shift pattern and the proposed transmission system and show the good performance in the change of shift position.

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A Study on the Estimation of Lane position using difference of Intensity (Intensity차를 이용한 차선의 위치 검출에 관한 연구)

  • 손경희;송현승;노도환
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.403-403
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    • 2000
  • Generally estimation of driving direction uses the way which uses lane detection and vanishing point in autonomous-driving system. Especially we use Sub-window for decreasing Process time when we detect lane, but fixed sub-window can not detect lane because of some factors in road image. So we suggest algorithm using one-dimension line scan method to detect an exact position of lane.

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THE EFFECT OF INTENSITY ON DURATION DISCRIMINATION

  • Jeon, J.Y.;Fricke, F.R.
    • Proceedings of the Acoustical Society of Korea Conference
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    • 1994.06a
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    • pp.879-884
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    • 1994
  • This paper reports on several experiments carried out to find the effects of intensity difference on duration discrimination in pairs of pure tones. Pure-tone signals were presented with the modification of amplitude and duration. Duration-discrimination thresholds for the musical tones and the signals that were varied in amplitude were investigated together with those of the fixed signals. From the results, it was found that the duration discrimination tasks are affected by an intensity difference of 20 phons.

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Determination of thermal Stress Intensity Factors for General Cusp-Crack Shaped Rigid Inclusion (일반 형상의 커프스형 강체균열에 대한 열응력세기계수 결정)

  • 이강용;장용훈
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.16 no.6
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    • pp.1216-1220
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    • 1992
  • In case that a general cusp-crack shaped inclusion expressed in a polynominal form of conformal mapping function exists in a two dimensional elastic body under uniform heat flow, the complex potential and thermal stress intensity factors are derived. Two thermal boundary conditions are considered, one an insulated rigid inclusion and the other a rigid inclusion with fixed boundary temperature. The previous solutions of the thermal stress intensity factors for symmetrical airfoil and lip type rigid inclusions are obtained from the general solution of the thermal stress intensity factors.

Finite Element Analysis of Subsurface Multiple Horizontal Cracks Propagation in a Half-space Due to Sliding Contact (유한요소법을 이용한 미끄럼 접촉시 내부 복수 수평균열 전파해석)

  • 이상윤;김석삼;권영두
    • Tribology and Lubricants
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    • v.16 no.5
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    • pp.373-380
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    • 2000
  • Finite element analysis is performed on the subsurface crack propagation in brittle materials due to sliding contact. The sliding contact is simulated by a rigid asperity moving across the surface of an elastic half-surface containing single and multiple cracks. The single crack, coplanar cracks and parallel cracks are modeled to investigate the interaction effects on the crack growth in contact fatigue. The crack location is fixed and the friction coefficients between asperity and half-space are varied to analyze the effect of surface friction on stress intensity factor for horizontal cracks. The crack propagation direction is predicted based on the maximum range of shear and tensile stress intensity factors. With a coplanar crack, the stress intensity factor was increased. However, with a parallel crack, the stress intensity factor was decreased. These results indicate that the interaction of a coplanar crack increases fatigue crack propagation, whereas that of a parallel crack decreases it.

A Optical System Design of LED Marine Lanterns Based on a TIR Collimator Lens (전반사 렌즈를 이용한 LED 등명기 광학계 설계)

  • Go, Dong Hyun;Lee, Yoon Chul
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.29 no.11
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    • pp.1-5
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    • 2015
  • In this paper, we propose the optical system design for a medium sized LED marine lanterns which simplifies the multi-layer structure into a single structure. In order to satisfy the target fixed intensity(35,000cd) and vertical divergence($-2.5^{\circ}{\sim}-4.0^{\circ}$, $+2.5^{\circ}{\sim}+4.0^{\circ}$), we use the total internal reflection collimator lens. And a Monte Carlo simulation has been utilized to optimize a condition of a LED package, TIR lens and outside lens. The computer simulation results indicated that this LED marine lanterns can produce of a fixed intensity(35,382cd) and vertical divergence($-3.1^{\circ}{\sim}+2.5^{\circ}$). Using the this optical system, we achieve the target value of LED lanterns.