• 제목/요약/키워드: thick and thin effect

검색결과 311건 처리시간 0.034초

Hot Plate장치를 이용한 TTD사 제조조건에 따른 사의 물성변화 연구 (Effect of Manufacturing Condition on the Physical Properties of TTD Yarns with Hot Plate Device)

  • 송민규;김희동;권오경
    • 한국의류산업학회지
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    • 제7권2호
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    • pp.247-251
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    • 2005
  • In this the study, the effects of the manufacturing process conditions on the properties Thick and Thin Diameter yarns(TTD yarns) prepared with hot plate device in the draw winder were determined. Physical properties including wet shrinkage, tenacity and elongation of the samples were measured and thick and thin effect was analysed with the evenness tester. The results were as the follows: There was little change the wet shrinkage of the TTD yarns in the range of $70^{\circ}C{\sim}80^{\circ}C$ of $R_1$ temperature(lower hot cylinder) with the same Hot Plate(H/P) temperature, but the wet shrinkage of the TTD yarns decreased 5-10% when $R_1$ temperature was $90^{\circ}C$. The wet shrinkage of the TTD yarns decreased with the H/P temperature at the same temperature of $R_1$. There was little effect of $R_1$ and H/P temperature on the tenacity of TTD yarns. The elongation of TTD yarns increased with $R_1$ temperature at the same H/P temperature. The elongation of TTD yarns increased little bit for the first time and then decreased above that temperature with increasing H/P temperature at the same $R_1$ temperature. The thick and thin effect on the TTD yarns was obvious in $110^{\circ}C$ of H/P temperature regardless of $R_1$ temperature, while there was no thick and thin effect on the TTD yarns in $140^{\circ}C$ of H/P temperature.

Magnetic Properties and Magnetoimpedance Effect in Mumetal Thin Films

  • Cho, Wan-Shik;Yoon, Tae-Sick;Lee, Heebok;Kim, Chong-Oh
    • Journal of Magnetics
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    • 제6권1호
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    • pp.9-12
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    • 2001
  • The dependence of the magnetoimpedance effect (MI) on magnetic properties has been investigated in mumetal thin films prepared by rf magnetron sputtering. Coercivity of thin films prepared at 400 W was about 0.4 Oe, and the magnetic anisotropy field of films deposited under a uniaxial magnetic field decreased with increasing film thickness. The saturation magnetization of mumetal films increased with rising input power and thickness and was smaller than that of permalloy films. Transverse incremental Permeability (TPR) of films of 1$\mu m$ thick increased with increasing effective permeability. The magneto impedance ratio (MIR) was proportional to TPR in films 1$\mu m$ thick but in spite of lower effective permeability at higher thicknesses, MIR increased due to skin effect. The height of the double peaks in the MIR curves decreased with decreasing anisotropy and thickness. The maximum MIR value for a 4$\mu m$ thick 75% at 36.5 MHz.

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Bilinear plate bending element for thin and moderately thick plates using Integrated Force Method

  • Dhananjaya, H.R.;Nagabhushanam, J.;Pandey, P.C.
    • Structural Engineering and Mechanics
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    • 제26권1호
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    • pp.43-68
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    • 2007
  • Using the Mindlin-Reissner plate theory, many quadrilateral plate bending elements have been developed so far to analyze thin and moderately thick plate problems via displacement based finite element method. Here new formulation has been made to analyze thin and moderately thick plate problems using force based finite element method called Integrated Force Method (IFM). The IFM is a novel matrix formulation developed in recent years for analyzing civil, mechanical and aerospace engineering structures. In this method all independent/internal forces are treated as unknown variables which are calculated by simultaneously imposing equations of equilibrium and compatibility conditions. In this paper the force based new bilinear quadrilateral plate bending element (MQP4) is proposed to analyze the thin and moderately thick plate bending problems using Integrated Force Method. The Mindlin-Reissner plate theory has been used in the formulation of this element which accounts the effect of shear deformation. Standard plate bending benchmark problems are analyzed using the proposed element MQP4 via Integrated Force Method to study its performance with respect to accuracy and convergence, and results are compared with those of displacement based 4-node quadrilateral plate bending finite elements available in the literature. The results are also compared with the exact solutions. The proposed element MQP4 is free from shear locking and works satisfactorily in both thin and moderately thick plate bending situations.

Outcomes of thin versus thick-wire snares for cold snare polypectomy: a systematic review and meta-analysis

  • Suprabhat Giri;Vaneet Jearth;Harish Darak;Sridhar Sundaram
    • Clinical Endoscopy
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    • 제55권6호
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    • pp.742-750
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    • 2022
  • Background/Aims: Cold snare polypectomy (CSP) is commonly used for the resection of colorectal polyps ≤10 mm. Data regarding the influence of snare type on CSP effectiveness are conflicting. Hence, this meta-analysis aimed to compare the outcomes and safety of thin- and thick-wire snares for CSP. Methods: A comprehensive search of the literature published between 2000 and 2021 was performed of various databases for comparative studies evaluating the outcomes of thin- versus thick-wire snares for CSP. Results: Five studies with data on 1,425 polyps were included in the analysis. The thick-wire snare was comparable to the thin-wire snare with respect to complete histological resection (risk ratio [RR], 1.03; 95% confidence interval [CI], 0.97-1.09), overall bleeding (RR, 0.98; 95% CI, 0.40-2.40), polyp retrieval (RR, 1.01; 95% CI, 0.97-1.04), and involvement of submucosa in the resection specimen (RR, 1.28; 95% CI, 0.72-2.28). There was no publication bias and a small study effect, and the relative effects remained the same in the sensitivity analysis. Conclusions: CSP using a thin-wire snare has no additional benefit over thick-wire snares in small colorectal polyps. Factors other than snare design may play a role in improving CSP outcomes.

내부 및 외부 원주방향 표면균열이 존재하는 배관의 두께효과를 고려한 소성한계하중 계산식 제시 (New Plastic Limit Load Equations of Pipes with Inner and Outer Circumferential Surface Cracks Considering Thickness Effect)

  • 김연수;허남수
    • 한국압력기기공학회 논문집
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    • 제15권2호
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    • pp.71-80
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    • 2019
  • In this study, limit load equations of thick-walled pipes with inner and outer circumferential surface cracks were derived based on force and moment equilibrium conditions. Since the limit load equations based on the mean radius at uncracked ligament, previously proposed by Kanninen et al., are based on the premise that the pipe wall thickness is relatively thin, the existing limit load solutions are only applicable to thin-walled pipes. In order to analyze the effect of the pipe thickness and surface crack depth on the limit load results, the predictions using the present limit load equations are compared with those using the existing solutions for thin-walled pipes. Being derived considering the thickness effect, the limit load solutions from this paper are believed to be more accurate for thick-walled pipes than the limit load equations presented for thin-walled pipes, and thus to be valuable equations for integrity assessment of thick-walled pipes.

판재 Al 2024-T3 합금재료의 두께효과를 나타내는 형상인자 및 하중인자에 의한 피로관계식 (A Fatigue Related Equation with Shape and Loading Factors Representing Effect of Thickness in Al 2024-T3 Alloy Sheet)

  • 김승권;이억섭;장주섭
    • 한국자동차공학회논문집
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    • 제20권1호
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    • pp.141-146
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    • 2012
  • Aluminum alloys have been used with various thicknesses suitable for light weight of structure. It is known that the thickness effect of material is an important factor affecting fatigue crack propagation under constant fatigue stress condition. In this work, we presented the behavior of fatigue crack propagation in thin plate compared to thick plate Al 2024-T3 alloy with referred thickness effect in a correlative equation determined by the shape factor and the loading factor. We chose two factors that are used in the correlative equation with considering that the experiments were carried out under a constant fatigue stress condition. The thickness ratio of thin plate compared to thick plate and the equivalent effective stress intensity factor ratio depending on thickness were chosen as shape and loading factors. A correlative equation is utilized to determine the equivalent effective stress intensity factor range of thin plate and identify the degree of increasing phenomenon of fatigue life in thin plate compared to thick plate.

P(VDF/TrFE) 필름의 두께에 따른 인체 감지형 초전형 PIR 적외선 센서의 특성 (Effect of P(VDF/TrFE) Film Thickness on the Characteristics of Pyroelectric Passive Infrared Ray Sensor for Human Body Detection)

  • 권성열
    • 센서학회지
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    • 제20권2호
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    • pp.114-117
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    • 2011
  • A thick 25 ${\mu}m$ thickness poled P(VDF/TrFE) film pyroelectric infrared ray sensor has been fabricated and then thin 1.6 ${\mu}m$ thickness P(VDF/TrFE) film pyroelectric infrared ray sensor has been fabricated also. These thick and thin P(VDF/TrFE) film pyroelectric infrared ray sensor was mounted in TO-5 housing to detect infrared light of 5.5 ~ 14 ${\mu}m$ wavelength for human body detecting with each other. The noise output voltage of the thick P(VDF/TrFE) film pyroelectric infrared ray sensor were 380 mV and NEP(noise equivalent power) is $3.95{\times}10^{-7}$ W which is the similar value with the commercial pyroelectric infrared ray sensor using ceramic materials as a sensing material. The NEP and specific detectivity $D^*$ of the thin P(VDF/TrFE) film pyroelectric infrared ray sensor were $2.13{\times}10^{-8}$ W and $9.37{\times}106$ cm/W under emission energy of 13 ${\mu}W/cm^2$ respectively. These result caused by lower thermal diffusion coefficient of a thin 1.6 ${\mu}m$ thickness PVDF/TrFE film than the thick 25 ${\mu}m$ thickness poled P(VDF/TrFE) film pyroelectric infrared ray sensor.

일반구조용 압연강재의 부식피로균열전파거동에 미치는 시험편 두께의 영향 (Effect of Specimen Thickness to Corrosion Fatigue Crack Propagation Behavior of Structure Rolled Steel)

  • 조약래
    • 수산해양기술연구
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    • 제28권3호
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    • pp.286-294
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    • 1992
  • In this paper, the corrosion fatigue crack propagation behavior of structure rolled steel (SWS 41C) was investigated by changing the thickness, and this experiment was done by the three point bending corrosion fatigue tester. The main results obtained are as follows: 1) As the thickness of specimen becomes thicker, the corrosion sensitivity to initial stage crack becomes some sensitive, and that the fatigue life becomes more sensitive. 2) The crack growth rate to initial stage crack (da/dN) was retarded as the thickness of specimen becomes thicker. But after initial stage crack, as the thickness of specimen is more thicker, da/dN is more rapid. 3) As the corrosion fatigue crack length grows, the accelerative factor of thick specimen (t=12mm) is more higher than that of thin specimen (t=6mm). 4) As the corrosion fatigue crack length grows, the corroson potential of both thick specimen and thin specimen becomes more less noble potential, however thick specimen (t=12mm) tends to more less noble potential than that of thin specimen(t=6mm).

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Effect of the Cu Bottom Layer on the Properties of Ga Doped ZnO Thin Films

  • Kim, Dae-Il
    • Transactions on Electrical and Electronic Materials
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    • 제13권4호
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    • pp.185-187
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    • 2012
  • Ga doped ZnO (GZO)/copper (Cu) bi-layered film was deposited on glass substrate by RF and DC magnetron sputtering and then the effect of the Cu bottom layer on the optical, electrical and structural properties of GZO films were considered. As-deposited 100 nm thick GZO films had an optical transmittance of 82% in the visible wavelength region and a sheet resistance of 4139 ${\Omega}/{\Box}$, while the GZO/Cu film had optical and electrical properties that were influenced by the Cu bottom layer. GZO films with 5 nm thick Cu film show the lower sheet resistance of 268 ${\Omega}/{\Box}$ and an optical transmittance of 65% due to increased optical absorption by the Cu metallic bottom layer. Based on the figure of merit, it can be concluded that the thin Cu bottom layer effectively increases the performance of GZO films as a transparent and conducting electrode without intentional substrate heating or a post deposition annealing process.

Axial frequency analysis of axially functionally graded Love-Bishop nanorods using surface elasticity theory

  • Nazemnezhad, Reza;Shokrollahi, Hassan
    • Steel and Composite Structures
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    • 제42권5호
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    • pp.699-710
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    • 2022
  • This work presents a comprehensive study on the surface energy effect on the axial frequency analyses of AFGM nanorods in cylindrical coordinates. The AFGM nanorods are considered to be thin, relatively thick, and thick. In thin nanorods, effects of the inertia of lateral motions and the shear stiffness are ignored; in relatively thick nanorods, only the first one is considered; and in thick nanorods, both of them are considered in the kinetic energy and the strain energy of the nanorod, respectively. The surface elasticity theory which includes three surface parameters called surface density, surface stress, and surface Lame constants, is implemented to consider the size effect. The power-law form is considered for variation of the material properties through the axial direction. Hamilton's principle is used to derive the governing equations and boundary conditions. Due to considering the surface stress, the governing equation and boundary condition become inhomogeneous. After homogenization of them using an appropriate change of variable, axial natural frequencies are calculated implementing harmonic differential quadrature (HDQ) method. Comprehensive results including effects of geometric parameters and various material properties are presented for a wide range of boundary condition types. It is believed that this study is a comprehensive one that can help posterities for design and manufacturing of nano-electro-mechanical systems.