In this paper, some of the most relevant patents of the last ten years on compact helical antennas are reviewed. Different technical solutions and their respective advantages and limitations are discussed. Both monofilar and quadrifilar helical antennas are addressed with different radiation characteristics. Some of these techniques can eventually be combined to improve further the axial length reduction. Only cylindrical designs are addressed in this paper, but most of the concepts could easily be applied to other shapes of helical antennas.
Patents relevant to spintronic memristor devices are reviewed. These patterns are selected from the categories of memristor, spintronic device, magnetic tunneling junction and magnetic domain wall devices. These patents address the questions of how to build spintronic memristor and how to use it. The list in this patents review is by no means complete and extensive. The purpose is to sparkle interests in this relatively new field.
Recent patents on piezoelectric energy harvesting transducer structures are reviewed in this article. The review considers the mechanical structures and application areas and also discusses the harvester efficiency, if referred to in the patents. Three main categories for piezoelectric energy harvesting based on the specific resonance frequency of the structure and impact and quasi-static excitation methods are presented and recent patents on each of these techniques are reviewed. Future development of energy harvester structures and the research field are also discussed.
Valves are used worldwide, in all climate zones, and under special local ambient conditions for various industrial plants. The continuous operation of the plants is highly dependent on the reliability of the valves. Failure of a valve may cause unscheduled plant shutdown or even severe accidents in process-controlled plants. Aiming to facilitate engineers and researchers in developing/implementing/improving the innovative techniques and advancing the technology, this paper provides an introduction and analysis for valve related issues, together with an extensive, yet not exhaustive, review of recent patents on valve health monitoring and diagnosis techniques.
In this paper, we proposed new compact DGS low-pass filters with broad stopband and low insertion loss in the pass band. The philosophy of the structure behind this new microstrip low-pass filters is simple as it is composed of a pair of Meander DGS-slots and an open-stub. One Filter will be realized through direct electromagnetic coupling and slow wave effect methods, on the other hand, the remaining filterate will be realized with the DGS and suspended method. With these configurations, the LPF with higher compactness, broad stopband and sharp transition characteristics was realized. The design formulae are derived by using an equivalent-circuit model of a parallel L-C resonator. In order to validate the feasibility of the proposed design method, a low-pass filter with 0.1-dB ripple is designed, fabricated, and measured. The Experimental results agree well with the simulation and analytical results. This article also refers some recent patent on filter designs.
There are some researchers who work in the design of the electronic circuits. In this paper, the mathematical models of four different and nonlinear electronic circuits are presented. The electronic models are nonlinear, because the model of the diode is nonlinear. In addition the comparison between the real circuits and the simulation of the mathematical models of the circuits are presented. The future research is to work in the design of the presented electronic circuits. The article presented some promising patents on the modeling of four nonlinear electronic circuits.
There has been significant recent interest of particle filter for the state estimation of the nonlinear stochastic system. Particle filter is a sequential Monte Carlo simulation based on nonlinear filtering algorithm for the nonlinear non- Gaussian filter problem. An overview of the status and development of research on particle filter is presented. The principle, evolution, and patents of particle filter algorithm are described and further research prospects are introduced.
This paper describes a recent progress in electret pressure sensor (EPS) technology. The EPS is constructed from a flexible thin-film electret, which is coated with transversally conducting metallic layers. The EPS can be used to measure pressure changes in wide frequency range and it can be manufactured in different shapes and sizes. Laboratory measurements confirm that using a careful preamplifier design the size of the EPS can be miniaturized to one square millimetre. The calibration procedure confirms that the EPS response is linear and it can be calibrated against the piezoresistive reference sensor. The article presented some promising patents on the thin-film electret pressure sensor technology.
Partial discharge (PD) is defined as a localized breakdown of a solid or liquid electrical insulation under high voltage stress. Partial discharge is a commonly known phenomenon to the power industry. The electromagnetic wave due to the partial discharge propagates along air, soil, and the high voltage cable and it can be detected by partial discharge detection devices. Partial discharge tests are commonly used to an extremely wide range of high voltage apparatus because Partial discharge (PD) detection may be the most efficient and most sensitive diagnostic method for high voltage apparatus. A lot of techniques have been developed to detect partial discharge signals. The paper reviews and compares some recent patents/patent applications regarding partial discharge detection and analysis.
In this paper we will present the main patents in the domain of the Carbon Nanotubes Field Effect Transistors (CNTFETs) based gas sensors. Although these devices have allowed to achieve sensors with an impressive sensitivity, compared to existing technologies, the physical interpretation of the effect of interaction between the gas molecules and the CNTFETs has not been clarified yet. This is pointed out not only by the scientific papers issued in the last years in the domain but also by the patents that have been filled. Considering that the selectivity is the main issue for this kind of devices, we will focus our analysis on the different routes that have been proposed in patents to overcome this problem : carbon nanotubes functionalization using polymers or biomolecules (e. g. DNA), electrodes metal diversification and metal decoration of Single-Walled-Carbon-NanoTubes (i.e. SWCNTs) mats. We will discuss about the physics behind each approach and we will try to compare them.
The noise detection and the data cleaning find application in data compressions for images and voice as well as in their analysis and recognition, data transmission, data reconciliation, fault detection and in general in all application area of the signal processing and measurements. This paper presents a short overview of some very recent inventions and other correlated literature which utilize methods of noise detection which are characterized by thresholding techniques. Moreover, the paper concentrates its attention on an innovative invention. The content of this paper can offer the possibility to improve the state of the art of all those procedures with denoising methods which use a thresholding technique implying a free thresholding one, running in wavelet packets. The author presents a technique which deals with a free thresholding method related to the on-line peak noise variance estimation even for signals with a small S/N ratio. The second innovative aspect consists of use of wavelet packets which give more elasticity to the technique. The basic idea is to characterize the noise like an incoherent part of the measured signal. It is performed through the wavelet tree by choosing the subspaces where the median value of the wavelet components has minimum. The paper provides to show general properties of the wavelet packets on which the proposed procedure is based. The developed algorithm is totally general even though it is applied by using Haar wavelet packets and it is present in some industrial software platforms to detect sensor outliers because of their easy structure. More, it is currently integrated in the inferential modeling platform