• Title/Summary/Keyword: Tension range

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Technique of Tension Length Calculation for 350km/h High Speed Catenary System (최고운행속도 350km/h급 전차선로 장력구간길이 계산 기법)

  • Chang, Sang-Hoon;Lee, Ki-Won;Kwon, Sam-Young;Park, Jae-Woong
    • Proceedings of the KSR Conference
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    • 2011.05a
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    • pp.932-939
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    • 2011
  • This paper deal with technique of tension length calculation for 350km/h high speed catenary system. Tension length affects in facility investment. Possibility of overlap increasing a tension length and the equipment investor decreases in order to decrease. Considers the parameter which specifies and the grudge which is possible long the fact that decides a tension length is the aim which is important plans overhead contact line. The element which decides a tension length with next following; (i) Operating range of tension device, (ii) Change of the horizontal tension which affects possibility of the effect which operates to the line and span, (iii) Tension of wire material the tensile force which is relation, (iv) Wire thermal expantion which relates with a standard temperature, (v) Curve radius, (vi) Wind velocity, (vii) Thermal range of overhead contact wire and mechanical design of tension mechanism etc.

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The Effect of Forward Head Posture and Cervical ROM on Chronic and Episodic Tension-Type Headache in University Students (대학생에서의 만성 및 특발성 긴장성 두통이 두부전방자세와 경추가동범위에 미치는 영향)

  • Chae, Yun-Won
    • The Journal of Korean Physical Therapy
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    • v.21 no.2
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    • pp.71-77
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    • 2009
  • Purpose: This study assessed the differences in the forward head posture (FHP), cervical range of motion, and headache clinical parameters in episodic tension-type headache (ETTH) subjects, chronic tension-type headache (CTTH) subjects, and healthy controls (university students). Methods: Fifteen CTTH subjects, 15 ETTH subjects and 15 controls without headache were examined. Side-view images of each group were taken in both the sitting and standing positions, in order to assess the FHP by measuring the craniovertebral angle. The CROM was used to measure the cervical range of motion. A headache diary was kept for 4 weeks to assess the headache intensity, frequency, and duration. Results: The craniovertebral angle was smaller, ie, there was a greater FHP, in the CTTH and ETTH subjects than in the healthy controls in both the sitting and standing positions (p<0.05). The CTTH and ETTH subjects showed a lower cervical range of motion than the healthy controls in the total range of motion as well as in the half-cycles (p<0.05). Conclusion: The increased FHP and decreased cervical range of motion might be a contributing factor in the initiation of tension-type headache.

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Influence of Surface Tension on Pinhole Phenomenon of Earthen Ware Glazes (도기유의 표면장력이 Pinhole 현상에 미치는 영향)

  • 지응업;이경재
    • Journal of the Korean Ceramic Society
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    • v.13 no.3
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    • pp.3-12
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    • 1976
  • The corelation between surface tensions and surface appearances of SK O5a opaque glazes for earthen wares were investigated. The surface tension values were theoretically calculated by using Dietzel's factors of constituent oxides of glaze. The surface appearances of glazes, especially the pinhole phenomena were strongly effected by the surface tension values showing the following general tendencies: (1) In the range of 305±3 dynes/cm of surface tensions, glazes showed almost no pjnholes. (2) In the range of surface tensions less than 300 dynes/cm, the large numbers of small pinholes or eggshell textures were observed. (3) In the range of surface tensions higher than 310 dynes/cm, large and deep pinholes were observed. (4) The contact angles of glazes on the wall tile body substrate are in the good proportional agreement with the surface tension values calculated by Dietzel's factors.

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Effect of The Bending Strain of FRP Tube for Composite Bushing with Winding Tension (와인딩 장력이 composite 부싱용 FRP tube의 굽힘변형에 미치는 영향)

  • Cho, Han-Goo;Yoo, Dae-Hoon;Kang, Hyung-Kyung
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2009.06a
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    • pp.380-381
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    • 2009
  • This paper describes effect of the bending strain of FRP tube for composite bushing with winding tension. The composite bushing can be formed, by adding silicone rubber sheds to a tube of composite materials. The FRP tube is internal insulating part of a composite bushing and is designed to ensure the mechanical characteristics. Generally the properties of FRP tube can be influenced by the winding angle, wall thickness and winding tension. As winding tension is increased glass contents was increased in the range of 70.4~76.6%. In the bending test, winding tension is increased residual displacement was decreased in the range of 14.0~12.2 mm.

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Properties of Composite Bushing with Filament Winding Tension (필라멘트 와인딩 장력에 따른 Composite Bushing의 특성에 관한 연구)

  • Cho, Han-Goo;Kim, Kwang-Yong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2010.03b
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    • pp.34-34
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    • 2010
  • This paper describes effect of the bending deformation of high voltage composite bushing with winding tension. The composite bushing can be formed, by adding silicone rubber sheds to a tube of composite materials. The FRP tube is internal insulating part of a composite bushing and is designed to ensure the mechanical characteristics. Generally the properties of FRP tube can be influenced by the winding angle, wall thickness and winding tension. As winding tension is increased glass contents was increased in the range of 70.4~76.6%. In the bending test, winding tension is increased residual deflection was decreased in the range of 14.0~12.2 mm.

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NEUTRON-INDUCED CAVITATION TENSION METASTABLE PRESSURE THRESHOLDS OF LIQUID MIXTURES

  • Xu, Y.;Webster, J.A.;Lapinskas, J.;Taleyarkhan, R.P.
    • Nuclear Engineering and Technology
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    • v.41 no.7
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    • pp.979-988
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    • 2009
  • Tensioned metastable fluids provide a powerful means for low-cost, efficient detection of a wide range of nuclear particles with spectroscopic capabilities. Past work in this field has relied on one-component liquids. Pure liquids may provide very good detection capability in some aspects, such as low thresholds or large radiation interaction cross sections, but it is rare to find a liquid that is a perfect candidate on both counts. It was hypothesized that liquid mixtures could offer optimal benefits and present more options for advancement. However, not much is known about radiation-induced thermal-hydraulics involving destabilization of mixtures of tensioned metastable fluids. This paper presents results of experiments that assess key thermophysical properties of liquid mixtures governing fast neutron radiation-induced cavitation in liquid mixtures. Experiments were conducted by placing liquid mixtures of various proportions in tension metastable states using Purdue's centrifugally-tensioned metastable fluid detector (CTMFD) apparatus. Liquids chosen for this study covered a good representation of both thermal and fast neutron interaction cross sections, a range of cavitation onset thresholds and a range of thermophysical properties. Experiments were devised to measure the effective liquid mixture viscosity and surface tension. Neutron-induced tension metastability thresholds were found to vary non-linearly with mixture concentration; these thresholds varied linearly with surface tension and inversely with mixture vapor pressure (on a semi-log scale), and no visible trend with mixture viscosity nor with latent heat of vaporization.

A Study on the LQG Precision Tension Control of a Dancer System for a Production of Printed Electronics in Roll-to-roll Systems (Roll-to-roll 시스템에서 인쇄전자 생산을 위한 댄서 시스템의 LQG 정밀 장력 제어에 대한 연구)

  • Seong, Jin-Woo;Kang, Hyun-Kyoo;Shin, Kee-Hyun
    • Journal of the Korean Society for Precision Engineering
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    • v.26 no.10
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    • pp.65-73
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    • 2009
  • For mass production of printed electronics in roll-to-roll fashion, precision tension control is important to reduce register errors. Register error should be minimized within several to tens of microns for many electronic devices to be manufactured through printing technology. In order to achieve this goal, tension disturbance must be attenuated before printing process within a certain range. In this paper, a certain tension range which allows maintaining register error within 10 micron was defined with specific operating conditions. A LQG controller was proposed instead of the conventional PI controller for precision tension control using a multivariable feedback. A guideline to determine design parameters for calculating LQ gain was proposed. The proposed LQG controller was compared to both PI controller and LQ regulator with white noise by numerical simulations. Results showed that the proposed LQG controller was effective for attenuating tension disturbance with white noise.

Effect of Initial Track Tension on the Tractive Performance of Tracked Vehicles (궤도의 초기 장력이 궤도 차량의 견인 성능에 미치는 영향)

  • 김채주;김경욱
    • Transactions of the Korean Society of Automotive Engineers
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    • v.5 no.2
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    • pp.1-12
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    • 1997
  • A computer program was developed to simulate effect of the initial track tension on the tractive performance of tracked vehicles. The performance was evaluated in terms of drawbar pull, motion resistance, tractive coefficient and tractive efficiency. Results of the simulation showed that increase in track tension decreases the sinkage and mean maximum pressure in clay, making the ground pressure distribution more uniform. This tendency became more evident when the number of roadwheels increased. However, such change in MMPs was negligible in firm soils. Motion resistance was also decreased with increase in track tension and the number of roadwheels. Under weak soil conditions, tractive coefficient and efficiency increased generally as the track tension increased for a slip range of 10∼30%. For slippage less than 3∼4%, however, the tractive coefficient decreased with increase in track tension. In general, it was known that increasing track tension improves tractive performance in weak soil conditions. However, high track tension can reduce efficiency due to the increment of internal motion resistance caused by increased track tension.

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Physical Properties of 1×1 Rib Knitted Fabrics Using A/W (A/W사로 편성한 1×1 리브편의 물성 평가)

  • Yea, Su-Jeong;Kim, In-Young
    • Fashion & Textile Research Journal
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    • v.14 no.4
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    • pp.629-634
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    • 2012
  • Knitted fabric using acrylic/wool blended yarn (A/W) is increasingly used in the knit industry; subsequently, research on knitted fabric using A/W has increased. This study presents an scientific database from evaluating physical properties of $1{\times}1$ rib stitch using A/W. In this study,$1{\times}1$ rib stitch using A/W were made at various knitting tensions (dial no. 2-6) and the number (4-6) of ply yarn. The physical properties of $1{\times}1$ rib stitch using A/W were measured and analyzed. The density was in the range 5.5-6.4 wales/cm and 4.0-5.6 courses/cm, respectively. The density increased when less plying yarns and more knitting tension were added during knitting. The thickness was in the range of 1.592-2.362 mm and the tensile strength was in the range 32.75-53.63 Kgf/mm. The burst strength was in the range 107.8-139.2 $N/cm^2$. Thickness, tensile strength, and burst strength increased as the number of ply yarn and the knitting tension increased. The elongation and the recovery extension rate were in the range 102.29-112.13% and 96.4-97.7%, respectively. The heat retention rate was in the range 59.3-65.1%. There was no difference of the elongation and the recovery extension rate and the heat retention rate by the knitting tension and the number of the ply yarn. The permeability was in the range 170.5-396.3 $cm^3/cm^2/sec$. Air permeability decreased as the number of ply yarn and the knitting tension increased. The pilling properties were excellent for all $1{\times}1$ rib stitches.

Effect of tension difference of kinesio tape applied to the tibialis anterior muscle on muscle strength, joint range of motion, and balance of the ankle joint in young college students (키네시오 테이프의 장력 차이가 젊은 대학생들의 발목 근력, 관절가동범위 및 균형에 미치는 영향)

  • Lee, Dae Hoon;Kim, Cho In;Shin, Gi Ha;Yeom, Yoo Jin;Kim, Ji Sung;Kim, Seong Ho
    • Journal of Korean Physical Therapy Science
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    • v.29 no.2
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    • pp.28-37
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    • 2022
  • Background: The purpose of this study was to investigate the effects of differences in the tension of Kinesio tape applied to the tibialis anterior muscle on muscle strength, joint range of motion and balance of ankle joint in young adults. Design: Randomized Controlled Trial. Methods: 41 young college students participated in this study. And the subjects were allocated randomly to two group. The experimental group had a tension difference (10%G, n=20). And there was no difference in tension in the control group (0%G, n=21). Jtech power track II, goniometer, and Biorescue were used to measure muscle strength, joint range of motion and balance. The paired t-test was performed to examine the differences within the groups before and after taping, and the independent t-test was performed to examine the differences between the groups. Result: 1) As a result of measuring muscle strength of each group, all measurements except 0%G of plantar flexion showed insignificant results. 2) Measurement of joint range of motion each group showed that neither 0%G nor 10%G was significant. 3) As a result of measuring the baladncing ability of each group there was a significant decrease in length, and average speed of the balancing capability (p<.05). 4) Comparisons between groups showed significant differences in the area among balance capability (p<.05). Conclusions: Based on these findings, the tension difference of Kinesio tape applied to the tibialis anterior muscle shows little effect on the muscle strength, range of motion, and balance of ankle joints. Given the current lack of research on the tension of kinesio tapes many studies are needed in the future to establish clear theories.