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91.
The aim of this study was to investigate the effect of elastane linear density, thread density, and weave float on the stretch, recovery, and compression properties of bi-stretch woven fabrics for compression garments. Fabric samples were produced using elastane core-spun cotton yarns both in the warp and weft. The elastane linear density, fabric thread density, and weave float size were used as input variables while fabric contraction, subgarment pressure, fabric stretch, and recovery were taken as response variables. Two different elastane linear densities, i.e. 44 and 78 dtex, two different thread densities, and three different weave designs, i.e. 1/1 plain, 2/2 z-twill, and 3/3 z-twill were used. The results of fabric samples were analyzed in Minitab statistical software. The coefficients of determinations (R-sq values) of the regression equations showed good prediction ability of the developed statistical models. The findings of the study may be helpful in deciding appropriate manufacturing specifications of bi-stretch fabrics to attain specific stretch, recovery, and compression properties. 相似文献
92.
The flow of hybrid nanoparticles with significant physical parameters with different base fluids in the presence of Biot number, velocity slip, and MHD effects has not been explored so far, particularly for a circular cylinder. Therefore, the current report is presented to offer a numerical solution for hybrid nanoparticles with base fluids (water and ethylene glycerol) via a circular cylinder. The physical situation is interpreted in terms of partial differential equations and is converted into ordinary differential equations after applying the similarity transformation. The results are presented in both tabular and graphical forms. The impact of physical parameters on velocity distribution is examined through graphs. The comparative results of hybrid nanoparticles for distinct base fluids as ethylene glycol and water are proposed and the hybrid nanoparticles with base fluid water seems to be greater than that of the hybrid nanoparticles with base fluid EG. The temperature profile of hybrid nanoparticles is found to be a decreasing function with growth in velocity slip parameter but an opposite trend is noted in case of nanoparticles . The skin friction and Nusselt number augmented for the increase in magnetic field, velocity slip, and nanoparticle while it shows a decreasing trend toward thermal slip parameter. For the both cases, improvement in Biot number helps enhance the heat transfer constantly. 相似文献
93.
Rizwan Ahmed Malik Ali Hussain Matias Acosta John Daniels Hyoung-Su Han Myong-Ho Kim Jae-Shin Lee 《Journal of the European Ceramic Society》2018,38(6):2511-2519
In this work, the relationship between the structural mechanisms and macroscopic electrical properties of the Nb-modified 0.96(Bi0.5Na0.84K0.16TiO3)–0.04SrTiO3 (BNKT–ST) system were elucidated by using temperature dependent and in situ synchrotron X-ray diffraction (XRD) techniques. For the composition x?=?0.0175, a large-signal piezoelectric coefficient (Smax/Emax?=?d33*) of 735 pm?V?1 at 6?kV mm?1 was observed at room temperature. Interestingly, at a higher temperature of 110?°C, the sample still showed a large d33* of 570 pm V?1. Furthermore, the temperature-invariant electrostrictive coefficient for this sample was found to be 0.0285?m4?C?2 over the temperature range of 25–170?°C. Moreover, the energy density for x?=?0.030 sample was ~1.0?J?cm?3 with an energy storage efficiency of ?70% in the temperature range of 25–135?°C. These results suggest that the synthesized Nb-modified BNKT–ST system is promising for the design of ceramic actuators as well as capacitor applications. 相似文献
94.
DE Allie M Lirtzman AP Malik JM Kowalski EA Barker CM Walker 《Canadian Metallurgical Quarterly》1998,66(4):1230-1235
Fascicle length, pennation angle, and tendon elongation of the human tibialis anterior were measured in vivo by ultrasonography. Subjects (n = 9) were requested to develop isometric dorsiflexion torque gradually up to maximal at the ankle joint angle of 20 degrees plantarflexion from the anatomic position. Fascicle length shortened from 90 +/- 7 to 76 +/- 7 (SE) mm, pennation angle increased from 10 +/- 1 to 12 +/- 1 degrees, and tendon elongation increased up to 15 +/- 2 mm with graded force development up to maximum. The tendon stiffness increased with increasing tendon force from 10 N/mm at 0-20 N to 32 N/mm at 240-260 N. Young's modulus increased from 157 MPa at 0-20 N to 530 MPa at 240-260 N. It can be concluded that, in isometric contractions of a human muscle, mechanical work, some of which is absorbed by the tendinous tissue, is generated by the shortening of muscle fibers and that ultrasonography can be used to determine the stiffness and Young's modulus for human tendons. 相似文献
95.
We have investigated the selective etching of 50 μm diameter via-holes for etch depth >200 μm using 30 μm thick photo resist mask in Inductively Coupled Plasma system with Cl2/BCl3 chemistry. Resultant etch rate/etch profiles are studied as a function of ICP process parameters and photo resist mask sidewall profile. Etch yield and aspect ratio variation with process pressure and substrate bias is also investigated at constant ICP power. The etch yield of ICP process increased with pressure due to reactant limited etch mechanism and reached a maximum of ∼19 for 200 μm depth at 50 mTorr pressure, 950 W coil power, 80 W substrate bias with an etch rate ∼4.9 μm/min. Final aspect ratio of etched holes is increased with pressure from 1.02 at 20 mTorr to 1.38 at 40 mTorr respectively for fixed etch time and then decreased to 1.24 at 50 mTorr pressure. The resultant final etch profile and undercut is found to have a strong dependence on the initial slope of photo resist mask sidewall angle and its selectivity in the pressure range of 20-50mTorr. 相似文献
96.
Three-dimensional shape recovery from one or multiple observations is a challenging problem of computer vision. In this paper, we present a new Focus Measure for the estimation of a depth map using image focus. This depth map can subsequently be used in techniques and algorithms leading to the recovery of a three-dimensional structure of the object, a requirement of a number of high level vision applications. The proposed Focus Measure has shown robustness in the presence of noise as compared to the earlier Focus Measures. This new Focus Measure is based on an optical transfer function implemented in the Fourier domain. The results of the proposed Focus Measure have shown drastic improvements in estimation of a depth map, with respect to the earlier Focus Measures, in the presence of various types of noise including Gaussian, Shot, and Speckle noises. The results of a range of Focus Measures are compared using root mean square error and correlation metric measures. 相似文献
97.
In the recent years, the 3D visual research has gained momentum with publications appearing for all aspects of 3D including visual tracking. This paper presents a review of the literature published for 3D visual tracking over the past five years. The work particularly focuses on stochastic filtering techniques such as particle filter and Kalman filter. These two filters are extensively used for tracking due to their ability to consider uncertainties in the estimation. The improvement in computational power of computers and increasing interest in robust tracking algorithms lead to increase in the use of stochastic filters in visual tracking in general and 3D visual tracking in particular. Stochastic filters are used for numerous applications in the literature such as robot navigation, computer games and behavior analysis. Kalman filter is a linear estimator which approximates system's dynamics with Gaussian model while particle filter approximates system's dynamics using weighted samples. In this paper, we investigate the implementation of Kalman and particle filters in the published work and we provide comparison between these techniques qualitatively as well as quantitatively. The quantitative analysis is in terms of computational time and accuracy. The quantitative analysis has been implemented using four parameters of the tracked object which are object position, velocity, size of bounding ellipse and orientation angle. 相似文献
98.
The application of conjunctive aggregation functions in fuzzy control systems with n inputs is discussed, and the effect of the choice of a continuous t‐norm in the inference phase for Takagi–Sugeno–Kang (TSK) systems is computed. A continuous t‐norm modeling AND connective in antecedent part of fuzzy rules can be reduced just to strict or nilpotent t‐norm. The isomorphism of strict (nilpotent) t‐norms enables simpler fitting of TSK fuzzy system parameters and reduces the computational complexity. Similar principle can also be used in the case of some noncommutative conjunctive aggregation functions modeling AND connective. The effect of the choice of a continuous t‐norm is then evaluated on well‐known case studies in fuzzy control, the Sinc function, and the urban traffic noise control system. 相似文献
99.
Mehrdad Rafat May Griffith Malik Hakim Lea Muzakare Frank Li K.C. Khulbe Takeshi Matsuura 《应用聚合物科学杂志》2007,106(3):2056-2064
Argon plasma treatment enhanced the attachment of epithelial cells to a collagen‐based artificial cornea crosslinked using glutaraldehyde (GA) and glutaraldehyde‐polyethylene oxide dialdehyde (GA‐PEODA) systems. The epithelialization of untreated and treated surfaces was evaluated by the seeding and growth of human corneal epithelial cells. Characterization of polymer surface properties such as surface hydrophilicity and roughness was also made by contact angle measurement and atomic force microscopy, respectively. Contact angle analysis revealed that the surface hydrophilicity significantly increased after the treatment. In addition, AFM characterization showed an increase in surface roughness through argon plasma treatment. Based on the biological and surface analysis, argon plasma treatment displays promising potential for biocompatibility enhancement of collagen‐based artificial corneas. It was also found that the cell attachment to artificial cornea surfaces was influenced by the combined effects of surface chemistry (i.e., surface energy), polymer surface morphology (i.e., surface roughness), and polar interactions between functional groups at the polymer surface and cell membrane proteins. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
100.
Ali Malik Dongdong Chen Younhee Choi Moon Ho Lee Seok-Bum Ko 《Electrical and Computer Engineering, Canadian Journal of》2008,33(3):169-175
With gate counts of ten million, field-programmable gate arrays (FPGAs) are becoming suitable for floating-point computations. Addition is the most complex operation in a floating-point unit and can cause major delay while requiring a significant area. Over the years, the VLSI community has developed many floating-point adder algorithms aimed primarily at reducing the overall latency. An efficient design of the floating-point adder offers major area and performance improvements for FPGAs. Given recent advances in FPGA architecture and area density, latency has become the main focus in attempts to improve performance. This paper studies the implementation of standard; leading-one predictor (LOP); and far and close datapath (2-path) floating-point addition algorithms in FPGAs. Each algorithm has complex sub-operations which contribute significantly to the overall latency of the design. Each of the sub-operations is researched for different implementations and is then synthesized onto a Xilinx Virtex-II Pro FPGA device. Standard and LOP algorithms are also pipelined into five stages and compared with the Xilinx IP. According to the results, the standard algorithm is the best implementation with respect to area, but has a large overall latency of 27.059 ns while occupying 541 slices. The LOP algorithm reduces latency by 6.5% at the cost of a 38% increase in area compared to the standard algorithm. The 2-path implementation shows a 19% reduction in latency with an added expense of 88% in area compared to the standard algorithm. The five-stage standard pipeline implementation shows a 6.4% improvement in clock speed compared to the Xilinx IP with a 23% smaller area requirement. The five-stage pipelined LOP implementation shows a 22% improvement in clock speed compared to the Xilinx IP at a cost of 15% more area. 相似文献