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61.
We present a particle-based method to simulate and visualize the interaction of knitwear with fluids. The knitwear is modeled using spring-mass systems and the fluid is modeled using the smoothed particle hydrodynamics method. Two-way coupling is achieved by considering surface tension, capillary, and interparticle forces between the fluid and knitwear. The simulation of fluid and knitwear particles is performed on the graphics processing unit. Photorealistic rendering of knitwear and fluid is achieved by using a hardware-accelerated rasterization-based rendering technique. Our method is able to simulate and visualize the macro- and microstructure of free-form knitwear and reflective and refractive characteristics of the fluid surface.  相似文献   
62.
Conductive polypyrrole (PPy)/kaolinite clay composites were prepared by in situ chemical polymerization of pyrrole in the presence of kaolinite using FeCl3 as oxidant. The PPy content and conductivity of the composites reached 32.8% and 8.3×10?2 S/cm at HCl concentrations of 1.5 M and 0.5 M, respectively. The microhardness of the composites containing different amounts of PPy was higher than that of the PPy and kaolinite components. The highest microhardness observed was 30.17 kg/mm2 for the composite containing 9.6% PPy. The electrical resistance of the composites was monitored during heating–cooling cycles over the range 5–120 °C. The change in resistance with temperature was more repeatable for the composite than for PPy. The composites were characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The humidity-sensing properties were also examined.  相似文献   
63.
In this article, a new complementary metal oxide semiconductor (CMOS) high-performance fully differential second-generation current conveyor (FDCCII) implementation is proposed. The presented FDCCII provides high-output impedance at terminals Z+ and Z?, good linearity and excellent output–input current gain accuracy. Also, the proposed FDCCII circuit operates at a supply voltage of ±1.3 V. The applications of the FDCCII to realise voltage-mode multifunction filters are given. Simulations are performed using TSMC CMOS 0.35-μm technology to verify theoretical results.  相似文献   
64.
In this paper, we consider large loss networks with fixed routing and multirate traffic. We use singlelink formulae and standard results on multidimensional Gaussian distributions to obtain upper bounds for blocking probabilities of new calls under light up to critical loading conditions. This is the loading regime of interest for many practical applications such as admission control in ATM networks. The main advantage of our approach is that the complexity does not scale with the size of the system, making it numerically attractive. Comparison with simulation results show that we get good upper bounds. We conclude by discussing the correlation between links in a network.  相似文献   
65.
We are presenting a fast new method of analysing a dielectric interface which is assumed to be cylindrically symmetrical. It is based on a multimode Gaussian beam development. Then two different cases are considered and we show the kind of results we can expect from this process. Finally, we explain in detail the relationships between the paraxial approximation and further justified simplifications which lead to an important calculation time decrease.  相似文献   
66.
Françis Toutain 《电信纪事》1998,53(9-10):389-405
Providing efficient and flexible quality of service guarantees within interogated services packet networks requires the deployment of advanced scheduling disciplines. This paper concentrates on the class of so-called fair queuing algorithms, firstly reviewing the general principle and its known approximations, then focusing on the service of adaptive applications, shedding light on the need to introduce a new scheduling paradigm, named dgps for decoupled generalized processor sharing; for the latter scheme an approximation technique is introduced and evaluated.  相似文献   
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Numerical and theoretical investigations are presented for a double screen frequency selective surface (DSFSS) with perfectly conducting Koch fractal patch elements. The work was developed in two steps, in the first step two Koch fractal FSS screens were designed using the commercial software Ansoft DesignerTM. In the second these FSS were cascaded and separated by an air gap layer, forming the so-called DSFSS, to improve the bandwidth behavior. Thereafter, a numerical cascading technique is used to analyze the effect of the air gap on the DSFSS. The results were compared and a good agreement was observed.  相似文献   
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