Vasculitis confined to the calves. Report of a case

Polyarteritis nodosa is a systemic disease of which limited forms have been reported, with the most common involving the skin. Only 13 cases with lesions confined to the calves have been reported to date. We report a new case.     

Performance analysis of SSE and AVX instructions in multi-core CPUs and GPU computing on FDTD scheme for solid and fluid vibration problems

In this work a unified treatment of solid and fluid vibration problems is developed by means of the Finite-Difference Time-Domain (FDTD). The scheme here proposed takes advantage from a scaling factor in the velocity fields that improves the performance of the method and the vibration analysis in heterogenous media. Moreover, the scheme has been extended in order to simulate both the propagation in porous media and the lossy solid materials. In order to accurately reproduce the interaction of fluids and solids in FDTD both time and spatial resolutions must be reduced compared with the set up used in acoustic FDTD problems. This aspect implies the use of bigger grids and hence more time and memory resources. For reducing the time simulation costs, FDTD code has been adapted in order to exploit the resources available in modern parallel architectures. For CPUs the implicit usage of the advanced vectorial extensions (AVX) in multi-core CPUs has been considered. In addition, the computation has been distributed along the different cores available by means of OpenMP directives. Graphic Processing Units have been also considered and the degree of improvement achieved by means of this parallel architecture has been compared with the highly-tuned CPU scheme by means of the relative speed up. The speed up obtained by the parallel versions implemented were up to 3 (AVX and OpenMP) and 40 (CUDA) times faster than the best sequential version for CPU that also uses OpenMP with auto-vectorization techniques, but non includes implicitely vectorial instructions. Results obtained with both parallel approaches demonstrate that massive parallel programming techniques are mandatory in solid-vibration problems with FDTD.     

Enhancing design-for-test for active analog filters by using CLP

We describe a computer-aided approach to automatic fault isolation in active analog filters which enhances the design-for-test (DFT) methodology proposed by Soma (1990). His primary concern was in increased controllability and observability while the fault isolation procedure was sketched only in general terms. We operationalize tionalize and extend the DFT methodology by using CLP() to model analog circuits and by a model-based diagnosis approach to implement a diagnostic algorithm. CLP() is a logic programming language which combines symbolic and numeric computation. The diagnostic algorithm uses different DFT test modes and results of voltage measurements for different frequencies and computes a set of suspected components. Ranking of suspected components is based on a measure of (normalized) standard deviations from predicted mean values of component parameters. The diagnosis is performed incrementally, in each step reducing the set of potential candidates for the detected fault. Case studies show encouraging results in isolation of soft faults of a given low-pass biquad filter.     

Thickness optimization of circular annular plate at buckling

This work deals with thickness optimization of a circular annular plate at buckling. The plate is loaded with uniform, axially symmetric, in-plane loads on the inner and outer edge. The variable thickness of the plate is approximated by a function of radial coordinates and design variables. An optimization problem is defined to find optimal sets of design variables which maximize buckling loads at constant weight/volume of the plate. The required buckling loads are determined according to the standard linear buckling equations, and the material is modelled by the small strain J₂ flow and deformation theories of plasticity where an elastic linear hardening rheological model is considered. Optimal thickness functions are determined for different support and load cases and the numerical results show that buckling loads can be increased significantly.     

Smart Home Tracking: A Smart Home Architecture for Smart Energy Consumption in a Residence with Multiple Users

Wireless Personal Communications - In this project, an architecture is implemented that can monitor and assist users in calculating their energy consumption by means of IoT technologies. It is...     

Measurement Accuracy of Oscillation‐Based Test of Analog‐to‐Digital Converters

Oscillation‐based testing of analog‐to‐digital converters represents a viable option for low‐cost built‐in self‐testing in mixed‐signal design. While numerous papers have addressed implementation issues, little attention has been paid to the measurement accuracy. In this letter, we highlight an inherent measurement uncertainty which has to be considered when deriving the parameters from the oscillation frequency.     

电池供电设备中的电荷泵

白色发光二极管(LED)广泛用于手持设备(如手机)以便从背后照亮彩色液晶显示器(LCD)或照明按键.LED的亮度与流经的电流量成正比,一般需要至少3V的正向电压.锂离子可充电电池因其相当高的能量密度而非常受欢迎,其输出电压可在4.2V(完全充电后)至3V(放电后)之间变化.该电压范围难以直接通过电池给LED供电,因此,需要某种形式的升压转换器.由于简单和成本低,自动调节式电荷泵特别适用于LED总电流为100mA的应用中.     

Dynamics of native oxide growth on CdTe and CdZnTe X-ray and gamma-ray detectors

We studied the growth of the surface oxide layer on four different CdTe and CdZnTe X-ray and gamma-ray detector-grade samples using spectroscopic ellipsometry. We observed gradual oxidization of CdTe and CdZnTe after chemical etching in bromine solutions. From X-ray photoelectron spectroscopy measurements, we found that the oxide consists only of oxygen bound to tellurium. We applied a refined theoretical model of the surface layer to evaluate the spectroscopic ellipsometry measurements. In this way we studied the dynamics and growth rate of the oxide layer within a month after chemical etching of the samples. We observed two phases in the evolution of the oxide layer on all studied samples. A rapid growth was visible within five days after the chemical treatment followed by semi-saturation and a decrease in the growth rate after the first week. After one month all the samples showed an oxide layer about 3 nm thick. The oxide thickness was correlated with leakage current degradation with time after surface preparation.     

Digital Curve Length Calculation by Using B-spline

A new method for digital curve length calculation based on the approximation with a B-spline has been introduced where the control points of a B-spline curve are the pixel center points. An approximate length of the digital curve is determined by calculating the length of the continuous B-spline curve. In the paper several examples are presented and the calculated lengths are compared to other methods found in the literature. The advantage of the proposed method is in the approximation of the digital curve with the continuous curve rather than with piecewise linear sections used by most other methods.