• Title/Summary/Keyword: Spinning

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Water Content Reduction in Poly(vinyl butylal) during Magic Angle Spinning

  • Han, Oc Hee;Jeong, SoonYong
    • Journal of the Korean Magnetic Resonance Society
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    • v.7 no.2
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    • pp.68-73
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    • 2003
  • Proton magic angle spinning spectra and thermogravimetric analysis data of poly(vinyl butylal) with water in it indicate water contents in the poly(vinyl butylal) samples were reduced during magic angle spinning. Our observation implies that the centrifugal force on the samples due to magic angle spinning cannot be neglected, especially on inhomogeneous and soft samples like poly(vinyl butylal) we tested in this work.

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A Study on Production Technology of PET Spun Yarn and Fabric Development by Using Spinning and Texturing Technologies

  • Sim, Seung-Bum
    • Proceedings of the Korean Society of Dyers and Finishers Conference
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    • 2009.03a
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    • pp.227-228
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    • 2009
  • This study was performed to develop a new PET yarn having the new appearance and touch effect of polyester (PET) yarn, using spinning and texturing technologies. The spinning technology is the manufacturing technology resulting in the denier difference in yarn filaments, and the texturing technology is the texturing conditions leading to spun yarn effects, using the filaments from the spinning processing.

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Study of stick-slip phenomena on spinning shaft (회전축계에서 발생하는 스틱슬립 현상 연구)

  • Kim, B;Chung, J
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2014.10a
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    • pp.250-251
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    • 2014
  • This paper investigates the stick-slip phenomena on spinning shaft. The modeling of the shaft is considered only torsional direction with nonlinear friction. The friction is adopted a negative friction-velocity slope. Based on the model, a nonlinear equation of motion is derived and analyze the stick-slip phenomena. In order to analyze the time dependent response, the nonlinear formulations are numerically solved by nonlinear Newmark method. The numerical results reveal the stick-slip phenomena on the spinning shaft system.

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Effects of Brain Spinning Program on Cognitive Function, Body Composition, and Health Related Fitness of Children and Adolescents (브레인스피닝 프로그램이 소아청소년의 인지기능, 신체조성, 건강관련체력에 미치는 영향)

  • Jun-Hyeok Kim;Wook Song;In-Soo Song;Hyun-Jun Kim;Byung-Gul Lim;Jung-Yoon Hur
    • Journal of The Korean Society of Integrative Medicine
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    • v.12 no.1
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    • pp.83-96
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    • 2024
  • Purpose : This study was conducted to determine the effects of a brain spinning program on cognitive function, body composition, health related fitness and physical self-efficacy of children and adolescents. Methods : This study, 34 children and adolescents were selected and divided into two groups : the exercise group (n=16), which received a brain spinning program and the control group (n=16), which did not receive any exercise program. The program was conducted for 30 minutes three times a week for 4 weeks, and the cognitive function, body composition, health related fitness and physical self-efficacy were measured both before and after the program. Results : The exercise group, which received a brain spinning program showed a significant increase in short-term memory (p<.05) and working memory (p<.01), and muscle mass increased significantly only in the exercise group (p<.05). In addition, left grip strength increased in the exercise group (p<.01), and the maximum oxygen intake decreased significantly only in the control group (p<.05), and Sit-forward bend increased significantly only in the exercise group (p<.01). Physical self-efficacy significantly increased only in the exercise group (p<.05). Conclusion : In summary, short-term memory, cognitive efficiency, working memory, muscle mass, left grip strength, maximum oxygen intake, and left forward bending in children and adolescents significantly increased after the 4-week brain spinning program. However, the control group that was not provided with the 4-week brain spinning program showed a significant increase in body weight and a significant decrease in maximum oxygen intake. In conclusion, the 4-week brain spinning program has positive effects on short-term memory, cognitive function, muscle mass, muscle strength, cardiorespiratory endurance, flexibility, and physical self-efficacy.

Characterization of Drawn Polyethylene by Solid State $^{13}C$ Magic Angle Spinning NMR

  • Han, Oc-Hee
    • Journal of the Korean Magnetic Resonance Society
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    • v.2 no.1
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    • pp.24-32
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    • 1998
  • Drawn polyethylene was studied by 13C cross polarization magic angle spinning techniques. Solid-solid phase transition from orthorhombic to monoclinic crystalline phase by drawing was observed. In addition, using a synchronized magic angle spinning 2 dimension technique, we confirmed that macroscopic ordering of the polyethylene was produced by drawing.

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Properties of Wool/Spandex Core-Spun Yarn Produced on Modified Woolen Spinning Frame

  • Dang, Min;Zhang, Zhilong;Wang, Shanyuan
    • Fibers and Polymers
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    • v.7 no.4
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    • pp.420-423
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    • 2006
  • Spandex has been successfully applied on modified worsted spinning system to produce spandex core spun yam. However it's difficult to produce wool/spandex core-spun yam on woolen spinning system with the same modified device because the drafting device of the two systems is quite different. A new method is introduced to apply spandex on woolen spinning system in this paper. Core-spun yam produced in this way has good appearance and quality by comparing with normal yam. A series of experiments were carried out to study the influence of spandex drafting ratio and yam twist factor on tensile' properties and elasticity of core-spun yams. The results indicate that core-spun yam with spandex drawing ratio of 2.5 and twist factor of 13.63 has highest value of tenacity and breaking elongation.

Structural Characteristics and Stress Relaxation Behaviors of PET Filament in High Speed Spinning (고속방사 PET Filament의 구조와 응력완화에 관한 연구)

  • Son, Kil Soo;Gu, Ja Gil;Yoon, Won Sik;Chang, Dong Ho
    • Textile Coloration and Finishing
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    • v.8 no.6
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    • pp.33-39
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    • 1996
  • The purpose of this study was to investigate the structural characteristics, mechanical properties, and stress-relaxation behavior of PET filament, which were prepared at various spinning speeds(1650, 3300, 4500, 5000, 5500, and 6000 m/min) and anneal(12$0^{\circ}C$, 20 min & 15$0^{\circ}C$, 40 min). In 4500 m/min of spinning speed the crystallinity, crystallite size, and degree of orientation of PET filament rapidly increased. By increasing spinning speed, the temperature dependence of stress-relaxation sharply decreased. Same results were obtained from heat-treated samples. As a result, activation energy for stress-relaxation increased with the crystallinity and spinning speed.

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A Finite Element Simulation of the V-Belt Pulley Spinning Process (V-벨트 풀리 스피닝 성형공정의 유한요소 시뮬레이션)

  • Kim S. J.;Kim H. R.;Lee T. K.;Kim Y. S.;Kim H. J.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2001.05a
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    • pp.81-84
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    • 2001
  • Some trials to simulate the spinning process by which V-belt pulley is usually being manufactured are done in this study. 2D finite element analysis (FEA) for the whole process to produce a mono-typed pulley including preforming, 1st spinning, axial compression and 2nd spinning processes is carried out using the commercial code $DEFORM2D^{TM}$. The sectional shape after each process is compared with that of real product. The deformed shape obtained from the FEA, on the whole, coincides with the experimental result well, but the thickness around the bottom of the V-groove is somewhat different each other.

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Calibration uncertainty of a spinning rotor gauge (스피닝 로터 게이지 교정 불확도)

  • 홍승수;임인태;신용현;정광화
    • Journal of the Korean Vacuum Society
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    • v.12 no.1
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    • pp.7-15
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    • 2003
  • Spinning Rotor Gauge (SRG) has been used to transfer standard gauge for international comparison at the high vacuum standards. We calibrated a spinning rotor gauge by using dynamic calibration system (DCS) that was a national high vacuum standards system. And its uncertainties were evaluated with the International Organization for Standardization (ISO), they were recognized ai A type uncertainty, B type uncertainty, combined Standard uncertainty, and expanded uncertainty. The combined standard uncertainties were $1.8007\times10^{-5}$ Pa ~ ~$4.8422\times10^{-5}$ Pa for this spinning rotor gauge.