Excellent voltage blocking capability and reliability can be obtained by trenching the field-limiting ring site which would be implanted. The trench etch step makes the junction depth deeper so that junction curvature effect and surface breakdown are less happened. The numerical analyses reveal two facts that the trenched field limiting ring has smaller maximum electric field and the electric field peak is deeper from the substrate surface, hence silicon dioxide layer can be protected. Therefore the voltage blocking capability and reliability of the new structure can be improved. The simulated results show that the trenched field limiting ring can have smaller critical electric field and accomplish near 30% increase of breakdown voltage in comparison with the conventional structure.

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ALM is an adaptive recursive algorithm which tries to express a multi-input multi-output system as a fuzzy combination of some single-input single-output systems. It uses a fuzzy curve fitting technique for behavior extraction or finding the input-output transformation of each of the single-input single-output systems, which called ink drop spread(IDS). In this paper we present a new implementation of a hardware unit implementing the ink drop spread (IDS) method.

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Neighborhood Preserving Embedding (NPE) is an unsupervised dimensionality reduction technique. Hence, it is lacking of discriminative capability. Zeng and Luo have proposed Supervised Neighborhood Preserving Embedding (SNPE), which uses class information of training samples to better describe data intrinsic structure. The robustness of SNPE has been demonstrated since it yields promising recognition results. However, there is no theoretical analysis to explain the good performance. Here, we show analytically that the neighborhood discriminant criterion, which manifested in the objective function of SNPE, is close resembled to Fisher discriminant criterion. SNPE is evaluated in ORL and PIE face databases. The inclusion of class information in data learning results superior performance of SNPE to NPE.

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In this paper we present a novel method for reducing the impact of variations in lighting on face recognition. We propose with adaptive singular value decomposition for the intensity image matrices in respective R, G, B color channels, adjusting the lighting compensation coefficient weights on the basis of mean distribution in RGB color space.

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In this paper, a multi-objective particle swarm optimization (PSO) algorithm is implemented to unveil trade-off margins of the CMOS two-stage operational amplifier (op-amp). Power dissipation, DC gain, equivalent input referred noise, area, slew rate, unity gain frequency (UGF) are used as objectives. Width and length of the gate of MOSFETS are free parameters. Simulation results revealed the design trade-off margins of the two-stage op-amp as expected theoretically.

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Block Data Transmission Systems (BDTS) are used in high-speed wireless communication systems with time dispersive channel characteristics. In such systems, blocks of data are separated by zeros to mitigate the effect of Inter-Symbol-Interference (ISI) between the blocks. An optimal detection process employs the Maximum Likelihood Block Detection (MLBD) technique on each block individually in the presence of ISI and Gaussian noise based on the Euclidean distance as an objective function. The detection process is computationally expensive therefore Genetic Algorithms have been used to reduce the overall design complexity. In this work, three types of Genetic Algorithms have been incorporated in the detection process i.e. the conventional GA, Micro GA(µGA), and Hybrid µGA to reduce computational load. In particular, a novel training method for Hybrid µGA has been proposed. Simulation results at 10dB channel SNR for the BDTS with Hybrid µGA executes as low as 3,750 number of objective functions evaluation for a block size of 20. The Bit Error Rate (BER) performance of this system is relatively good i.e. around 1dB inferior to the BDTS using the Exhaustive Search method that requires as many as 2²⁰ number of objective functions evaluation.

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A high-performance field programmable gate array (FPGA) implementation of full pipelined computation structure is proposed for sharp finite-impulse -response (FIR) filters using the frequency response masking (FRM) technique. The FRM-based FIR (FFIR) filter consists of a novel symmetrical systolic array of a interpolated FIR(IFIR) filter in cascade to a pair of nonsymmetrical systolic arrays of masking FIR filters mainly. These filters are designed based on inner-product computation involving MAC operation which can be realized by the DSP block in the latest FPGA device efficiently. The realization results on a Xilinx Virtex-5 chip show that the proposed FPGA implementation can obtain higher throughput but consumes less resource compared to the equivalent conventional sharp FIR (CSFIR) filter that developed by the Core Generator software tool.

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A bridge resistance deviation-to-period (BRD-to-P) converter is presented for interfacing resistive sensor bridges. It consists of a linear operational transconductance amplifier (OTA) and a current-controlled oscillator (CCO) formed by a current-tunable Schmitt trigger and an integrator. The free running period of the converter is 1.824ms when the bridge offset resistance is 1kΩ. The conversion sensitivity of the converter amounts to 3.814ms/Ω over the resistance deviation range of 0-1.2Ω. The linearity error of the conversion characteristic is less than ±0.004%.

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Mach-Zehnder (MZ) lanthanum-modified lead-zirconate-titanate (PLZT) electro-optic modulators were fabricated on a silicon substrate by aerosol deposition. The fabricated modulator has a reversed-ridge-waveguide structure (with a 1.8-µm-wide ridge) and electrodes for applying a voltage perpendicular to the PLZT core layer. The modulator also has an MZ interferometer structure in which the device length and the electrode length of phase shifter are 1.5mm and 500µm, respectively. Optical-characteristics measurements showed that the 2-GHz optical output signal was produced by the modulator. The optical performance proves the validity of using the modulators on silicon substrates for on-chip optical interconnects.

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Erbium-doped tantalum oxide films were prepared by radio-frequency magnetron sputtering. Visible light emission was observed from the films after annealing. We obtained PL peaks at 550 and 670nm. The effects of erbium concentration, annealing temperature, and annealing time on the light-emitting properties of the films are discussed. The strongest intensities of the 550 and 670nm peaks were observed from the samples with 0.96 and 0.63mol% erbium concentrations after annealing at 900°C for 20min, respectively.

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In this paper, a novel parametric active contour is proposed for image segmentation. It integrates the wavelet transform and self-affine mapping system to effectively compute the external force of parametric active contours. For this purpose, after smoothing the image by a Gaussian kernel, the wavelet coefficients are computed. Then, sub-forces of each wavelet scale were computed by using contractive self-affine maps. Finally, the total self-affine force field was obtained by superposition of these sub-forces. Experimental results demonstrated the superior performance of the proposed algorithm compared to a number of frequently-used active contours for medical images.

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This study proposes a practical method to estimate the random error in real part of refractive index measured with terahertz time domain spectroscopy (THz-TDS) for the single measurement of sample by using the phase spectra of the reference terahertz electric field and their standard deviation. The validity of this method is based on the experimental result that the phase correlates with its standard deviation and the signal to noise ratio is almost equal in the phase spectra of reference and sample signal. The random error estimated from the proposed method fitted well to the statistically computed standard deviation.

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This paper discusses the quantification of parasitic components inherent in printed circuit board (PCB) wiring, which can be of considerable value in power conversion circuits. The influence of parasitic inductance and mutual coupling are evaluated in terms of electromagnetic compatibility (EMC) for the switching operation of power MOSFETs in a dc-dc buck converter. The parasitic components are identified based on the partial element equivalent circuit (PEEC) method and modeled with circuit simulation. The estimated effect of the parasitic component on the switching operation of a power MOSFET is validated by comparing it with experimental results.

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