A mathematical method to realize complex poles in a high-order passive switched-capacitor filter

A high-order discrete-time IIR low-pass with complex poles using charge sampling is presented in a single-stage structure by using a mathematical strategy. In comparison with the analog complex-poles G_m-C filters, the proposed filter consumes lower power and has good linearity, and all of the tunings are implemented only by capacitor sizes. The proposed filter is a seventh-order Butterworth, but this method can be generalized to implement other complex pole filters like Tchebyshev and Elliptic. Post-layout simulation results in 130-nm complementary metal-oxide-semiconductor (CMOS) show an IIP3 of +18 dBm and a noise figure of 5 dB. The filter has a rejection of more than 110 dB in its stop band and consumes 1.5 mW with a 1.6-V supply voltage, and circuit occupies an about 0.12 mm² of silicon.     

From 2D to 3D geodesic-based garment matching

Multimedia Tools and Applications - A new approach for 2D to 3D garment retexturing is proposed based on Gaussian mixture models and thin plate splines (TPS). An automatically segmented garment of...     

Preparation of tin ferrite–tin oxide by hydrothermal,precipitation and auto-combustion: photo-catalyst and magnetic nanocomposites for degradation of toxic azo-dyes

In this work, tin ferrite nanoparticles were first synthesized by simple chemical procedures such as co precipitation, sol–gel auto combustion and hydrothermal methods. In general, all three methods were compared in the synthesis of nanoparticles. Then tin ferrite–tin oxide (50%:50%) nanocomposites were prepared using co precipitation method. Crystal structures of nanoparticles and nanocomposite were studied using X-ray diffraction pattern. The particle size was determined by Scanning Electron Microscopy. Vibrating sample magnetometer was used to study the magnetic property of the products. And also, by applying Fourier transform infrared spectrometer, the purity of the material was determined. Photocatalytic activity of nanoparticles and nanocomposites was investigated under ultra-violet and visible spectroscopy (UV–Vis). The results show that prepared nanocomposites are applicable for magnetic and photocatalytic performance and they were able to degrade azo dyes (organic dyes) under UV–Vis radiation.     

An integrated weighted fuzzy multi-objective model for supplier selection and order scheduling in a supply chain

This paper presents a new weighted fuzzy multi-objective model to integrated supplier selection, order quantity allocation and customer order scheduling problem to prepare a responsive and order-oriented supply chain in a make-to-order manufacturing system. Total cost and quality of purchased parts as well as the reliability of on-time delivery of customer orders are regarded as the objectives of the model. On the other hand, flexible suppliers can contribute to the responsiveness and flexibility of entire supply chain in the face of uncertain customer orders. Therefore, a mathematical measure is developed for evaluating the volume flexibility of suppliers and is considered as the other objective of the model. Furthermore, by considering the effect of interdependencies between the selection criteria and to handle inconsistent and uncertain judgments, a fuzzy analytic network process method is used to identify top suppliers and consider as the last objective. In order to optimise these objectives, the decision-maker needs to decide from which supplier to purchase parts needed to assemble the customer orders, how to allocate the demand for parts between the selected suppliers, and how to schedule the customer orders for assembled products over the planning time horizon. Numerical examples are presented and computational analysis is reported.     

A decoupled source current reconstruction method for noisy and reactive near‐field to far‐field transformation

In this article, a decoupled source current reconstruction method (SRM) for noisy and reactive near‐field (NF) to far‐field (FF) transformation is introduced. It is shown that the traditional SRM for NF/FF transformation shows instability in the regions that the amounts of noise or reactive radiations are noticeable. Therefore, in these regions, equivalent currents should be determined from a Tikhonov SRM equation. However, this equation increases the computational cost of the SRM. To simplify the Tikhonov SRM equation, a Tikhonov radial field retrieval algorithm is also proposed. In this algorithm, the Tikhonov integral equation is decoupled by considering and retrieving the radial components of the electric field. Results of far‐field calculation with both the proposed Tikhonov SRM equation and Tikhonov radial field retrieval algorithm with three different antennas are presented and compared with those of the full‐wave simulation and measurements. The results show more accurate field transformation with the proposed algorithms.     

Preparation and characterization of a novel gelatin–poly(vinyl alcohol) hydrogel film loaded with Zataria multiflora essential oil for antibacterial–antioxidant wound‐dressing applications

This study was performed to evaluate the properties of poly(vinyl alcohol) (PVA), gelatin, and PVA–gelatin dispersions and films enriched with Zataria multiflora essential oil (ZO). The results reveal that the ζ potential, particle size, and viscosity values and the antioxidant and antibacterial activities of the dispersions changed significantly with the addition of ZO to the polymer matrix. Changes in the properties of the dispersions suggested the presence of interactions between PVA or gelatin and ZO. Such interactions could affect the mechanical and water‐barrier properties of the films. ZO induced remarkable decreases in the tensile strength, elastic modulus, and swelling and increases in the elongation at break, solubility, and water‐vapor permeability of the films. Scanning electron microscopy analyses proved the impact of ZO on the film morphology, which affected the film properties, including the mechanical and water‐barrier properties. The addition of ZO to the polymer led to a coarse film microstructure because of the hydrophobic ZO aggregates, which produced discontinuities in the film matrix. ZO considerably increased the antioxidant and antibacterial activities of the dispersions. Pseudomonas aeruginosa was the most resistant bacteria. The improved antioxidant and antimicrobial activities of the PVA–ZO and gelatin–ZO indicated that such products could effectively be used as wound dressings. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45351.     

Dielectric Structure with Periodic Strips for Increasing Radiation Power of Photoconductive Antennas: Theoretical Analysis

Low terahertz (THz) radiation power and low efficiency are the well-known drawbacks of photoconductive antennas (PCAs). To increase THz-radiation power of PCAs, a dielectric structure with periodic low-temperature-grown GaAs strips is proposed. Transmitted power of the proposed structure is obtained from a theoretical model, and further confirmed by finite element simulations. Results show that the structure is capable to transmit into the substrate 90 % of the power of transverse magnetic wave with wavelength as wide as from 0.7 to 1.0 μm. Favorability of this property gets amplified when power transmission in a wide range of frequency bandwidth is desired, e.g., for optical pulse with short duration time incident to PCA, which generates carriers in the semiconductor that create THz emission. Furthermore, the proposed dielectric structure with periodic strips, the whole structure placed in between electrodes of PCA is considered, and analyzed by the existing photoconductive antenna equivalent circuit model, to see how power radiation changes. Interestingly, THz-radiation power enhancements of 70 and 20 % are evinced for, respectively, 20 and 150 mW incident optical powers as instances, as compared to PCA without strips in the gap area.