Defect Level and Fault Coverage in Coefficient Based Analog Circuit Testing

Test techniques for analog circuits characterize the input-output relationship based on coefficients of transfer function, polynomial expansion, wavelet transform, V-transform or Volterra series. However, these coefficients always suffer from errors due to measurement accuracy and noise. This paper presents closed form expressions for an upper bound on the defect level and a lower bound on fault coverage achievable in such analog circuit test methods. The computed bounds have been validated on several benchmark circuits. Further, application of these bounds to scalable RC ladder networks reveal a number of interesting characteristics. The approach adopted here is general and can be extended to find bounds on defect level and fault coverage in other component based test methods for linear circuits.     

Parametric Fault Testing of Non-Linear Analog Circuits Based on Polynomial and V-Transform Coefficients

This paper is an exposition of recent advances made in polynomial coefficient and V-transform coefficient based testing of parametric faults in linear and non-linear analog circuits. V-transform is a non-linear transform that increases the sensitivity of polynomial coefficients with respect to circuit component variations by three to five times. In addition, it makes the original polynomial coefficients monotonic. Using simulation, the proposed test method is shown to uncover most parametric faults in the range of 5–15?% on a low noise amplifier (LNA) and an elliptic filter benchmark. Diagnosis of parametric faults clearly illustrates the effect of enhanced sensitivity through V-transform. Finally, we report an experimental validation of the polynomial coefficient based test scheme, with and without V-transform, using the National Instruments’ ELVIS bench-top testbed. The result demonstrates the benefit of V-transform.     

Broadband dielectric characterization of TiO2 ceramics sintered through microwave and conventional processes

In this work the microwave sintering (MW) of pure submicron rutile TiO₂ powder has been conducted in complete electric field using a single mode cavity of 2.45 GHz and without any susceptor. The sintering conditions were varied and similar sintering cycles were also done using a conventional furnace (CV), in carefully measuring the temperature in both processes. The dielectric properties, from kHz to GHz were determined and a comparison analysis was made between microwaved and conventional sintered specimens. It is shown that microwave sintering allows to obtain dense material (>95%) in a very short time (10–15 min) at a sintering temperature ranging from 1000 °C to 1300 °C. Some samples are fully dense (>99% theoretical density) after being microwave heated for ～10 min at ～1300 °C. Using the microwave heating, the processing temperature to get high dense material (i.e. >94%) is lowered by ～150–175 °C compared to conventionally sintered samples. It is also shown that an annealing in air at ～800 °C for ～4 h, leads to very low loss TiO₂ ceramic in the entire frequency range investigated. Owing to the lowest sintering temperature provided by microwaves, the low frequency dielectric losses are smaller for MW samples than for CV sintered samples. Among the highest reported microwave Q factors (～7350) have been measured on pure TiO₂ samples exhibiting the largest grain size (～1.5 μm) and density (>96%).     

Filtered two‐fluid models of fluidized gas‐particle flows: New constitutive relations

New constitutive relations for filtered two‐fluid models (TFM) of gas‐particle flows are obtained by systematically filtering results generated through highly resolved simulations of a kinetic theory‐based TFM. It was found in our earlier studies that the residual correlations appearing in the filtered TFM equations depended principally on the filter size and filtered particle volume fraction. Closer inspection of a large amount of computational data gathered in this study reveals an additional, systematic dependence of the correction to the drag coefficient on the filtered slip velocity, which serves as a marker for the extent of subfilter‐scale inhomogeneity. Furthermore, the residual correlations for the momentum fluxes in the gas and particle phases arising from the subfilter‐scale fluctuations are found to be modeled nicely using constitutive relations of the form used in large‐eddy simulations of single‐phase turbulent flows. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3265–3275, 2013     

Effect of Li2O on structure and optical properties of lithium bismosilicate glasses

Bismuth–silicate glasses containing lithium oxide having composition xLi₂O·(85 − x)Bi₂O₃·15SiO₂ (5 ≤ x ≤ 45 mol%) were prepared by melt quench technique. Density, molar volume and glass transition temperature for all the glass samples were measured. IR spectroscopy was used for structural studies of these glasses in the range from 400 to 1400 cm⁻¹. The increase of Li₂O content in glass matrix results in the decrease of the Si–O–Si bond angle and increase in the covalence nature of Bi–O bond. IR spectra suggest the presence of distorted [BiO₆] octahedral units and the degree of distortion increases with the addition of Li₂O in these glasses. The optical transmission spectra in the wavelength range from 200 to 3300 nm were recorded and optical band gap (E_g) was calculated. The values of E_g lie in between 2.81 and 2.98 eV. The values of average electronic oxide polarizability as well as optical basicity in these glasses were found to be dependent directly on Bi₂O₃/Li₂O ratio.     

智能电网设备层WIA-PA无线网络的维护语义度量

为应对不同服务质量需求并提升智能电网通信的系统能力及可靠性,提出一种无线智能电表双路径维护基于因果树的认知技术. 因果树通过定义智能电表程序中的度量和事件之间的因果关系,以实现有效推理. 路径维护度量根据接收信号强度指标和数据包接收成功率明确了链路状态、链路质量、相应的动态转换等路由问题. 基于信道和电磁干扰所做的物理实验用于评估该种无线智能电表的可靠性.     

Application of Glass Transition in Food Processing

The phenomenon of glass transition has been employed to food products to study their stability. It can be applied as an integrated approach along with water activity and physical and chemical changes in food in processing and storage to determine the food stability. Also associated with the changes during agglomeration crystallization, caking, sticking, collapse, oxidation reactions, nonenzymatic browning, and microbial stability of food system. Various techniques such as Differential Scanning Calorimetry, Nuclear Magnetic Resonance, etc. have been developed to determine the glass transition temperature (T_g) of food system. Also, various theories have been applied to explain the concept of T_g and its relation to changes in food system. This review summarizes the understanding of concept of glass transition, its measurement, and application in food technology.     

Effect of copolymers containing glycidyl methacrylate functional groups on the rheological,mechanical, and morphological properties of poly(ethylene terephthalate)

The aim of this work was to investigate the effect of ethylene‐glycidyl methacrylate (EGMA) and ethylene‐methyl acrylate‐glycidyl methacrylate (EMAGMA) copolymers on the rheological, mechanical, and morphological properties of Poly(ethylene terephthalate) (PET). The results of torque rheometry showed an increase in the torque of PET with the addition of EGMA and EMAGMA copolymers due to the reactions between the GMA groups present in the copolymers and the carboxyl and hydroxyl groups present in PET. The torque of PET/copolymer blends increased with the increase in the copolymer content and was more pronounced for the blends containing EGMA copolymer. X‐ray diffraction and differential scanning calorimetry analyzes showed that neat PET and the PET in PET/copolymer blends are amorphous. The addition of EGMA and EMAGMA copolymers delayed the crystallization of PET. Rheological measurements showed an increase in the viscosity at low frequencies with the addition of EGMA and EMAGMA copolymers to PET. This increase was more pronounced for PET/copolymer blends containing higher amount of copolymers and for the blends containing EGMA, corroborating the results obtained by torque rheometry. The impact strength of PET/EMAGMA blends was higher than that of PET/EGMA blends. Morphology analysis by SEM showed that PET/EMAGMA blends presented higher average dispersed phase domains size than PET/EGMA blends. POLYM. ENG. SCI., 59:683–693, 2019. © 2018 Society of Plastics Engineers     

Purification of β-galactosidase from recombinant Pichia pastoris using aqueous two-phase separation technique

In the current investigation, aqueous two-phase methodology with polyethylene glycol (PEG) 6000/phosphate salt has been used for single-step purification of β-galactosidase from recombinant Pichia pastoris. Optimized parameters with 12% (w/w) salt concentration, 25% (w/w) polymer concentration, 0.6 (mg/ml) protein load and 0.1 M ionic concentration resulted in a maximum of 4.7 purification fold with a 97% yield. The enzyme kinetic study of purified protein revealed V_m and K_m of 97.087 (U/mg), 0.027(U/mg), 0.07 (U/mg) and 0.7 (mM), 11.13 (mM), 10.73 (mM) with O-nitrophenyl-β-D-galactopyranoside, lactose and milk substrate, respectively.     

Two dimensional N-doped ZnO-graphitic carbon nitride nanosheets heterojunctions with enhanced photocatalytic hydrogen evolution

The effective separation of photogenerated charge carriers, their transport and interfacial contact is of great significance for excellent performance of semiconductor based photocatalysts. Herein, we report the fabrication of two dimensional (2D) nanosheets heterojunction comprising of N-doped ZnO nanosheets loaded over graphitic carbon nitride (g-C₃N₄) nanosheets for enhanced photocatalytic hydrogen evolution. The prepared 2D-2D heterojunctions with varying amount of g-C₃N₄ nanosheets have been characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and x-ray photoelectron spectroscopy (XPS) techniques. The optimized heterojunction photocatalyst with 30 wt% of g-C₃N₄ nanosheets (NZCN30) exhibit hydrogen evolution rate of 18836 μmol h^?1 g_cat^?1 in presence of Na₂S and Na₂SO₃ as sacrificial agents under simulated solar light irradiation. The enhanced photocatalytic performance of NZCN30 heterojunction has been supported well by photoluminescence and photoelectrochemical investigations, which shows the minimum recombination rate and high photoinduced current density, respectively. In addition, the existence of 2D-2D interfacial contact plays a major role in enhanced H₂ evolution by high face-to-face contact surface area for separation of photogenerated charge carriers in space which facilitate their transfer for H₂ generation. This work paves way for the development of 2D-2D heterojunctions for diverse applications.