In this paper we apply computer visualization techniques such as computer (3D) graphics, animation, and photorealistic color rendering to the simulation of dynamical processes and control systems in limited-resource e...
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In this paper we present some enlightening results to show why and how stability assessment for Linear Time-Varying (LTV) systems based solely on the location of the "frozen-time eigenvalues (FTE)" fails to ...
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A class of linear-phase finite impulse response (FIR) digital filters for sampling rate conversion is introduced. These filters consist of two cascaded parts. The first part is a parallel connection of two or three br...
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The authors outline an edge-prediction-adjustment strategy for the detection of diffused edges using an image pyramid structure. An initial edge map is obtained from an appropriate high-level image of the pyramid usin...
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The authors outline an edge-prediction-adjustment strategy for the detection of diffused edges using an image pyramid structure. An initial edge map is obtained from an appropriate high-level image of the pyramid using a conventional edge detection method. Next, using a simple linear interpolation, the predicted edge map for the adjacent low-level image is determined. Based on the information of the predicted edges, edge adjustment is carried out using a sequential search in a small neighborhood of each of the predicted edges with the aid of a dynamic programming based method. Simulation results on both synthetic and medical images indicate that the performance of the proposed approach is much better than that of the commonly used differential of a Gaussian-based approach.< >
The optical properties of thin film microcrystalline silicon (μc-Si:H) prepared by plasma-enhanced chemical vapor deposition (PECVD) have been studied by real time spectroscopie ellipsometry in the nucleation regime ...
The optical properties of thin film microcrystalline silicon (μc-Si:H) prepared by plasma-enhanced chemical vapor deposition (PECVD) have been studied by real time spectroscopie ellipsometry in the nucleation regime as isolated crystalline particles increase in size. A simple geometric model of nucleation allows us to remove the dominant effect of voids and extract the dielectric functions of the crystallites themselves. We find that the results can be understood in terms of a classical size effect whereby limitations on the electron mean free path by scattering at crystallite surfaces control the absorption onset from 2.0 to 3.0 eV. Finally, we describe how well-ordered, continuous 15 Å c-Si films can be prepared on metal substrates.
An algorithm for converting relay ladder logic (RLL) programs for programmable logic controllers (PLCs) into sequential function chart (SFC) programs is introduced. Since an SFC (a standardization of Grafcet) better r...
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An algorithm for converting relay ladder logic (RLL) programs for programmable logic controllers (PLCs) into sequential function chart (SFC) programs is introduced. Since an SFC (a standardization of Grafcet) better represents the sequential flow of control logic, it is considerably easier to understand and modify SFC programs. Existing RLL programs are converted into SFC programs by recovering the underlying sequential control logic. This conversion of the program representation is referred to as design recovery. A basic design recovery algorithm is presented and applied to a simple RLL program for one stage of a batch chemical process. Several fundamental issues in discrete control logic representation and analysis are also identified as fertile areas for future research.< >
Sub-100 nm P+/N junctions are fabricated by implanting wafers in the plasma immersion ion implantation system (PIII). Ions from SiF4 and BF3 plasmas are implanted at energies from 4-6 keV and 2 keV, respectively. The ...
Sub-100 nm P+/N junctions are fabricated by implanting wafers in the plasma immersion ion implantation system (PIII). Ions from SiF4 and BF3 plasmas are implanted at energies from 4-6 keV and 2 keV, respectively. The amorphous region formed by SiF4 im-plantion is shown to be effective in slowing B diffusion during a 10 sec, 1060°C rapid thermal anneal step. Channeling and transmission electron microscopy studies show the recrys-tallized amorphous region is comparable in quality to an unprocessed Si wafer, and the implantation and annealing sequence has no detrimental effects on the physical or electrical characteristics of fabricated devices. Diodes have forward ideality factors of 1.05 to 1.06 and reverse leakage as low as 2 nA/cm2 in the diode bulk at -5 V applied bias.
A novel method is reported for reducing the proximity effect in high‐resolution electron beam patterning of high atomic number materials such as tungsten. The method involves interposing a thin (50–400 nm) layer of ...
A novel method is reported for reducing the proximity effect in high‐resolution electron beam patterning of high atomic number materials such as tungsten. The method involves interposing a thin (50–400 nm) layer of SiO2 between the resist and the underlying high‐Z substrate. Examples are shown in which gratings of 0.2 μm lines with a 0.5 μm period were written without proximity effect compensation. Optimal intermediate layer thickness for the best resolution of the gratings is determined to be 200 nm. A Monte Carlo model of electron scattering including inelastic processes has been implemented to interpret our experimental results. The model presented shows that having the low atomic number SiO2 layer between the resist and the tungsten prevents the fast secondary electrons being generated at the surface of the tungsten from propagating back into the resist, suggesting a mechanism for proximity effect reduction. The results presented here have important practical applications for x‐ray mask making.
Results on limit cycle oscillations in floating-point implementations of recursive filters are reviewed. Special attention is paid to structures with a single floating-point nonlinearity in the recursive filter loop, ...
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Results on limit cycle oscillations in floating-point implementations of recursive filters are reviewed. Special attention is paid to structures with a single floating-point nonlinearity in the recursive filter loop, for which efficient criteria are proposed to guarantee the absence of limit cycles. Both unlimited exponent range limit cycles and underflow limit cycles are considered. Also results on wave digital filters and related structures are discussed.< >
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