• Title/Summary/Keyword: filament

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Studies on the Organization of 10-nm Filament Ring in Saccharomyces cerevisiae (Saccharomyces cerevisiae 의 10-nm Filament Ring 의 생성기작에 대한 연구)

  • 김성철;정재욱;김형배
    • Korean Journal of Microbiology
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    • v.30 no.5
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    • pp.333-338
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    • 1992
  • Saccharomyces cerevisiae contains 10-nm tilament ring which lies just under the inner surface of the plasma membrane within the mother-bud neck. Although H)-nm filaments may he involved in cellular morphogenesis. their role and organization are not clear. Here we report the production of antihodies specific for the CDel2 protein hy use of gene fusion techniques. and studies on the organization and function of IO-nm filaments using these antibodies. The CDCl2 protein arc translated through the whtlle cell cycle and present in the cytosol. 'They are polymerized just before bud emergence and unpolymerized alier cytokinesis. and do not have organizational relationship with actin. Thc possible role of 10-nm filaments is the determination of bud emergence site and completion of cytokinesis.

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Two-Ribbon Filament Eruption on 29 September 2013

  • Kim, Yeon-Han;Bong, Su-Chan;Lee, Jaejin;Cho, Il-Hyun;Park, Young-Deuk
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.74.2-74.2
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    • 2014
  • We have presented a classic two-ribbon filament eruption occurred in the east side of NOAA active region 11850 at 21:00 UT on 29 September 2013. Interestingly, this filament eruption was not accompanied by any flares and just there was a slight brightening in X-rays, C1.2, associated with the eruption. An accompanying huge CME was appeared at 22:12 UT in the LASCO C2 field of view and it propagates into the interplanetary space with a speed of about 440 km/s. And the related solar proton event (S2) started at 05:05 UT and peaked at 20:05 UT on 30 September 2013. The CME arrival was recorded by the ACE spacecraft around 01:30 UT on 2 October 2013. Around the CME arrival time, the solar-wind speed reached at about 640 km/s and IMF Bz showed southward component (-27 nT). Finally, the filament eruption and the CME cause geomagnetic storm (G2) at 03:00 UT on 2 October 2013. We described the detailed evolution of the filament eruption and its related phenomena such as CME, proton event, geomegnetic storm and so on. In addition, we will discuss about the activation mechanism of the filament eruption without flares.

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A Study on the Optimum Evaluation Method for Tensile NOL Ring Specimen Manufactured by Filament Winding Process (Filament winding에 의해 제조된 복합재료 NOL RING시험편의 최적 인장강도 평가법에 관한 연구)

  • 권순철;임철문;배창원;엄수현;김윤해
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2000.11a
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    • pp.203-207
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    • 2000
  • Filament Winding Process is a comparatively simple operation in which continuous reinforcements in the form of roving are wound over a rotating mandrel. And now well established as a versatile method for storage tanks and pipe for the chemical and other industries . In this study, tensile strength of a filament wound ring specimens were evaluated by split disk test fixture and dress disk test fixture , The results obtained from experiments were compared with the theoretical values obtained by the rule of mixtures. And the purpose of this paper is the suggestion of an appropriate test method for the evaluation of tensile properties of filament wound structures .The tensile strength of a ring specimen tested by the dress disk test showed better agreement with the theoretical values than of a ring specimen tested by the split disk test because the stress concentration in edges of a split disk test fixture is more severe than that of dress disk test fixture. The results showed that the tensile strength of a ring specimen was influenced by the geometry of test fixture, the continuity of fibers, fiber-tension, fiber-end and stress concentration in specimen.

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Numerical Calculation of the Far Field Acoustic Pressure from the Unsteady Motion of the Three-dimensional Vortex Filament (삼차원 와선의 비정상 거동에 의한 원거리 음압의 수치해석)

  • Ryu, Ki-Wahn;Lee, Duck-Joo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.21 no.6
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    • pp.942-950
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    • 1997
  • Far field acoustic pressure from the evolution and interaction of three-dimensional vortex filament is calculated numerically. A vortex ring is a typical example of the three-dimensional vortex filament. An elliptic vortex ring emits a strong sound signal due to significant distortion and stretching of the vortec filament. The far field acoustic pressure is linearly dependent on the third time derivatives of the vortex positions. A numerical scheme of high resolution is employed to describe in detail the elliptic vortex ring motions which ar highly nonlinear. Descretized vortex filaments are interpolated by using a parametric blending function to remove a possible numerical instability. The distorted vortex filament, owing to the self-induced and the induced velocity from the other vortex segments, is redistributed at each time step. The accuracy and efficiency of the scheme are validated by comparisons with the analytic solution of circular vortex ring interaction.

Effect of Pretreatment on Dyeability and Functionalities of Summer Rayon fabrics Finished by Gallnut Extract (전처리가 오배자 추출물에 의한 여름용 인견직물의 염색 및 기능성 향상에 미치는 영향)

  • Hwang, Hyun Ju;Hong, Kyung Hwa
    • Fashion & Textile Research Journal
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    • v.18 no.2
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    • pp.244-251
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    • 2016
  • Viscose rayon filament fabrics have been called 'artificial silk' and beloved as summer clothing materials for a long time in Korea. This is because the viscose rayon filament fabrics reveals glossy surface and cool touch feeling compared to other conventional fabrics composed of staple fibers. Therefore, we tried to prepare the higher value added viscose rayon filament fabrics for summer textile products. In this study, we applied gallnut extract to the viscose rayon filament fabric to develop summer fabrics with natural color and multi-functions such as antibacterial and antioxidant properties. This process also pursue eco-friendly and multi-functional fabric finishing from the natural material "gallnut". In addition, various pre-treatment with cationizer, chitosan, or chito-oligomer was applied to the finishing process to improve the finishing efficacy and durability. Consequently, it was found that the active component of gallnut extract was successfully incorporated to the viscose rayon filament fabric through a pad-dry-cure process. And, the treated viscose rayon filament fabrics showed excellent antibacterial and antioxidant properties. Therefore, it was expected that the rayon filament fabrics treated by gallnut extract could be used as effective summer fabrics preventing the growth of bacteria and skin ageing as well as providing cool touch feeling. However, the pre-treatments were not that meaningful on the functionalities but effective on coloring.

A Study on Filament Winding Tension Control using a fuzzy-PID Algorithm (퍼지-PID 알고리즘을 이용한 필라멘트 와인딩 장력제어에 관한 연구)

  • 이승호;이용재;오재윤
    • Journal of the Korean Society for Precision Engineering
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    • v.21 no.3
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    • pp.30-37
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    • 2004
  • This thesis develops a fuzzy-PID control algorithm for control the filament winding tension. It is developed by applying classical PID control technique to a fuzzy logic controller. It is composed of a fuzzy-PI controller and a fuzzy-D controller. The fuzzy-PI controller uses error and integrated error as inputs, and the fuzzy-D controller uses derivative of error as input. The fuzzy-PI controller uses Takagi-Sugeno fuzzy inference system, and the fuzzy-D controller uses Mamdani fuzzy inference system. The fuzzy rule base for the fuzzy-PI controller is designed using 19 rules, and the fuzzy rule base for the fuzzy-D controller is designed using 5 rules. A test-bed is set-up for verifying the effectiveness of the developing control algorithm in control the filament winding tension. It is composed of a mandrel, a carriage, a force sensor, a driving roller, nip rollers, a creel, and a real-time control system. Nip rollers apply a vertical force to a filament, and the driving roller drives it. The real-time control system is developed by using MATLAB/xPC Target. First, experiments for showing the inherent problems of an open-loop control scheme in a filament winding are performed. Then, experiments for showing the robustness of the developing fuzzy-PID control algorithm are performed under various working conditions occurring in a filament winding such as mandrel rotating speed change, carriage traversing, spool radius change, and reference input change.

A Study on the Shielding of Orbit by 3D Printed Filament in Brain CT (Brain CT검사 시 3D프린터 필라멘트에 따른 수정체 차폐 연구)

  • Choi, Woo Jeon;Kim, Dong Hyun
    • Journal of the Korean Society of Radiology
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    • v.15 no.2
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    • pp.101-108
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    • 2021
  • The CT can accurately present the anatomical structure of an organ in the human body, and the resolution of the image is excellent. On Brain CT examination, the radiation sensitivity of the orbit is high and it is subject to many exposure effects. To reduce exposure dose of lens, this study compares change of exposure dose and shielding rate about non-shielding and shielding in a way of using two shielding materials, bismuth and tungsten. In this study, we used bismuth and tungsten filament as shielding materials made by 3D printing to measure the exposure dose according to the materials thickness and each of slices. To compare each shielding rate, 1 mm to 5 mm of two materials was measured with the head phantom fixed and the Magicmax universal dosimeter placed on the eye when the shielding material is not placed, and the shielding material is placed on it. In the 1 mm thick filament, the bismuth filament showed 26.8% and the tungsten filament showed 43.1% shielding rate. Therefore, tungsten presents much greater shielding effect than bismuth.

The isobaric effect correction and measurement of the Ru isotopes by thermal ionization mass spectrometry (열 이온화 질량분석기를 이용한 Ru 동위원소 측정 및 동중원소 영향 보정)

  • Jeon, Young-Shin;Kim, Jung-Suk;Han, Sun-Ho;Song, Kyu-Seok
    • Analytical Science and Technology
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    • v.23 no.5
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    • pp.498-504
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    • 2010
  • It is very difficult to get stable ion peak intensity of ruthenium by thermal ionization mass spectrometry because of its high ionization potential and high volatility of its oxides which causes to lose much of ruthenium ions, so the intensity of the signal decrease quickly. Accordingly, a study was performed in oder to increase the ionization efficiency and to prevent sample losses due to volatilization and to check with isobaric effect by impurities in filament for the measurement of ruthenium isotopes. Both single filament and double filament were tested. The former was proved to be more efficient for the stable and strong intensity of signal and revealed less isobaric effect from the molybdenum (Mo) as a filament impurity. Also, when the temperature of filament increased too high, the isobaric effect from Mo greatly appeared. That is, Mo impurity from filament gave a serious effect for measuring the ruthenium isotopes. It was proved to be of importance that filament current should be slowly increased with time interval. Finally, ruthenium isotopes were accurately measured by correction with measuring $^{94}Mo/^{99}Ru$.

Fluoro-illite/polypropylene Composite Fiber Formation and Their Thermal and Mechanical Properties (불소화 일라이트/폴리프로필렌 복합섬유 형성 및 열 및 기계적 특성)

  • Jeong, Euigyung;Lee, Young-Seak
    • Applied Chemistry for Engineering
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    • v.22 no.5
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    • pp.467-472
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    • 2011
  • This study investigated illite/polypropylene (PP) composite filament formation via melt-spinning and evaluated their physical properties to prepare functional fibers using natural materials. When composite filaments were formed, the composite filaments exhibited smaller fiber diameters compared to that of neat PP filament because of the lubricant effect of illite induced by its layered structure. Moreover, fluorination effect increased interfacial affinity and dispersion in the polymer, resulting in smaller diameter of fluorinated illite/PP composite filament, which was 2/3 of the neat PP filament diameter. Addition of raw and fluorinated illite improved thermal stability of illite/PP composite filament. Raw illite/PP composite filament cannot be used for a practical application, because it broke during drawing process, whereas the fluorinated illite/PP composite filament can be used for a practical application, because it exhibited similar tensile strength of the neat PP filament and 50% increased modulus. Even with improved illite/PP interfacial affinity and illite dispersion in the polymer, illite/PP composite filament formed microcomposite, because non-expandable illite had strongly bound layers, resulting in only a little illite exfoliation and PP intercalation into illite.

Dynamic Characteristics Analysis of Filament-wound Composite Towers for Large Scale Offshore Wind-Turbine (대형 해상풍력발전용 필라멘트 와인딩 복합재 타워의 동적 특성에 관한 연구)

  • Han, Jeong-Young;Hong, Cheol-Hyun;Jeong, Jae-Hun;Moon, Byong-Young
    • The KSFM Journal of Fluid Machinery
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    • v.15 no.4
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    • pp.55-60
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    • 2012
  • The purpose of this study is to investigate the buckling load of filament-wound composite towers for large scale wind-turbine using finite element method(FEM). To define material properties, we used both the effective property method and the stacking properties method. The effective properties method is to assume that composite consists of one ply. The stacking properties method is to assume that composite consists of some stacked plies. First, linear buckling analysis of the tower, filament-wounded with angles of [${\pm}30$] was carried out by two methods for composite material properties, the stacking method and the effective method. and FE analysis was performed for the composite towers according to filament winding angles of [${\pm}30$], [${\pm}45$], [${\pm}60$]. FE analysis results using the stacking properties of the composite were in good agreement with the results by the effective properties. The difference between FEM results by material properties methods was approximately 0~2.3% in buckling Analysis and approximately 0~0.6% in modal analysis. And above the angle of [${\pm}60$], there was a little change of buckling load.