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Eddy-current rail displacement sensors are used for confirming rail displacement. However, collision with gravel and snow due to the short distance between rail head surface and sensor causes failures or malfunctions. Therefore, it is necessary to increase the distance from the rail head surface to the eddy-current rail displacement sensor. In this paper, the use of triangle spiral coils make rail...
In this presentation we will introduce and discuss a general approach to the synthesis of metasurfaces for full control of reflected and transmitted fields. The method, which is applicable for any linear metasurface, is based on the use of an equivalent Z-matrix, connecting the tangential field components at the two sides on the metasurface. Finding the impedance matrix components, we are able to...
The tactile and visual texture measurement by multimodal MEMS sensor is reported. This MEMS sensor has two function in a structure: force-sensitivity of resistance of microcantilevers embedded in the elastomer and light-sensitivity of a MOS structure on the Si substrate. Deflection of the cantilever induced by applied force depends on the tactile texture including hardness, thickness, and roughness...
We report on the use of catechol for the electrochemical activation of acid-functionalised single-walled carbon nanotubes immobilised on glassy carbon electrodes. Following well-published methods for catechol activation of bare glassy carbon electrodes, these studies show the efficacy of extending the method to activation of carbon nanotubes. Voltammetric scans in catechol show an increase in current...
A Ku-band, electronically-steerable, artificial-impedance-surface antenna (AISA) was designed, fabricated and measured. It is capable of scanning in elevation from −5° to 80° with gain variation of less than 3 dB. The antenna operates by launching a surface wave along a surface-wave waveguide (SWG) whose impedance elements are rectangular patches with electrically tunable capacitors between them....
Here, we study the reflection and transmission characteristics of mushroom-type structures with the diodes inserted at the center along the direction of the wires. The analysis is carried out using the nonlocal homogenization model for the mushroom structure with the generalized additional boundary conditions at the connection of the wires through the diodes. It is observed that the reflection/transmission...
Dense metallic grids can create surfaces that are conductive at microwave frequencies yet optically transparent. However, fullwave solutions of such grids are computationally expensive. To accelerate simulations of complex structures we consider three approximate models for a wire grid. Circuit-based models provide estimates of radiation efficiency for simple antennas without simulating the complex...
This paper present a design circuit CMOS in 0.5um to detected QCM resonant frequency and QCM peak current for calculate mass weight of load on QCM surface. The QCM resonant frequency was changed by mass on QCM surface and QCM peak current depended on QCM resonant frequency. The differential of QCM resonant frequency (Δf) between QCM unloaded and QCM with loaded on surface can use for calculate mass...
The calculation method of electrical characteristics of the flat transparent antenna with metal triangle in the base is developed. The method is based on the solution of the integral equation for the current along the transparent conductive film. Ways of such antennas optimization are sown.
Solder joints on the Printed-Circuit board (PCB) serve as mechanical and electrical connections. Their function maybe simple, but the reliability of the solder joints may affect the entire device or system. They are usually the weak links when the electronic products are exposed to a variety of load conditions from their operation and storage, such as temperature cycling, vibration, shock and humidity...
The volume integral equation used in the method of moments based resistance and inductance extractors is reduced to a novel surface integral equation featuring a global surface impedance boundary condition as well as a product of volume and surface integral operators. The reduction is achieved by employing the equivalence principle representation of the electric field in the conductor cross-section...
Radiation impedance is one of the important parameters in designing efficient and wideband capacitive micro-machined ultrasonic transducer (CMUT) arrays. It determines how much acoustical power is generated in the surrounding medium given the membrane motion. Recently, considerable effort has been put to characterize the radiation impedance of CMUT arrays in conventional uncollapsed regime. However,...
The effect of polyethylene glycols upon copper electrodeposition in methanesulfonate electrolytes is discussed in this paper. By means of linear sweep voltammetry and electrochemical impedance spectroscopy, it is found that polyethylene glycols in methanesulfonat electrolytes have very different behavior from that in traditional sulfuric electrolytes. PEG can adsorb on electrode surface in absent...
Electrochemical Impedance Spectroscopy (EIS) has been widely used in biological studies like tissue and cells characterization, both in vivo and in vitro. The objective of this study was to investigate cells adhesion over a microelectrodes array by monitoring the electrical impedance. A comprehensive electrical model of the cell-electrode interface has been used to fit experimental data. The electrode...
In this paper, a thin planar electromagnetic absorber consisting of two lossy Frequency Selective Surface (FSS) layers is introduced. The layers are separated by foam material and they are backed by the ground plane. Square rings and crossed dipoles are used in the design of these lossy layers. A wideband absorption characteristic is achieved for zero degrees of incidence angle which is the main point...
This paper presents the investigation of vertically folded monopoles on a circuit board, where the two radiation arms are at the top and bottom dielectric surfaces, respectively, connected through vias at the end. It basically maintains the same antenna area of a printed monopole since the clearance is necessary on the opposite side. Two types of miniaturized resonant folded monopoles including L-shape...
In this paper a new method is presented for calculation of frequency-dependent impedance in a straight. The mentioned method is compared with two other approaches which are conventionally used in high frequencies impedance calculation. The new method is relatively fast and simple and its results are admissibly accurate and conforms the conventional methods.
A detailed numerical model that integrates DC forward current, emitter recombination and I-region width and radius for simulation of PIN diodes used at high power levels is presented. Details on the model are provided so that easy implementation by the reader may be performed. It is shown that for certain PIN diode geometries, the analytic methods can underestimate the surface recombination current...
We introduced a new low-profile UWB monopole antenna to achieve overhorizon operation from low VHF frequencies up to 2 GHz. The curvature profile of proposed Inverted-Hat Antenna is logarithmically related to the distance from the feed point, and thus results in a frequency-independent performance. The eleven-ellipse IHA is the most frequency-independent design. Other outer surface growth profiles...
Energy harvesting systems based on the transformation of acoustic vibrations into electrical energy are increasingly being used for niche applications due to the reduction in power consumption of modern day electronic systems. Typically these applications involve extracting energy at remote or isolated locations where local long term power is unavailable or inside sealed or rotating systems where...
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