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Graphene has drawn a huge research interest in chemical and biological sensor applications, since its first discovery in 2004, primarily due to its high surface to volume ratio, high carrier mobility and unsaturated sp2 bonds at the surface. Although many different graphene-based chemical sensors have been reported, its application in biological sensors is quite limited so far. Nonetheless, graphene-based...
AlGaN/GaN based heterostructures have attracted significant research interests in recent years for sensing very small scale displacement utlizing their unique piezoelectric properties. AlGaN/GaN heterojunction based Field Effect Transisitors (HFETs), when embedded at the base of a GaN cantilever, can be utilized to transduce a very small displacement with much higher Gauge Factor (GF) than their Si...
In this paper, a wind field was designed to meet the test requirements through analyzing the experimental requirements of unmanned helicopter wind resistance. If we want to test the performance of UAV wind resistance, we have to get the wind speed at the UAV. There are two problems that we would to face, one is that it is a wind field with wind speed decay, and the other is that we want to do this...
Miniaturization of radio frequency identification (RFID) reader front-end circuit based on low temperature co-fired ceramic (LTCC) is studied in this paper. LTCC makes the dimension of the circuit a reduction of about 30% which is compared with the traditional circuit substrate in ultra high frequency (UHF) band. It makes the size of RFID front-end circuit more compact than the traditional one.
This paper proposes a capacitive miniature PIFA works at UHF band. Double-layer mushroom structure EBG is used as a reflector of the PIFA instead of PEC. The size of the new PIFA is 1/8 of the operation wavelength and 1/2 of the traditional one. The EBG structure enhances the radiation efficiency of the antenna about 33.3%.
This paper gives a brief introduction of the state of art of robotics standardization. Based on the analysis of the electric power industry and robotics technology, a vision for electric power robotics standardization is presented. And related fundamental standards and specific robotic standards are developed as a case study.
A set of measurement system for the testing of transmission lines, composing of wireless center station, wireless current acquisition and transmission nodes, wireless voltage acquisition and transmission node, was designed, which was based on wireless communication. The high speed wireless bridge working at 2.4GHz together with the clock synchronization module based on the IEEE1588 communicating protocol...
In order to judge commutation failure faster and more accurately, a new prognosis method was proposed. The physical mechanism of a three-phase full wave rectifier circuit was analyzed, and an arc angle formula based on impedance parameters was proposed to judge commutation failure. It's easy to get the information of impedance parameters, thus this prognosis method based on impedance parameters is...
Based on our completed design of a surface mounted transverse flux permanent magnet motor (SM-TFPM) with auxiliary stators, a concentrated-flux transverse flux permanent magnet motor (CF-TFPM) is designed and the hard-to-fasten auxiliary stators are canceled by appropriate flux path design, moreover, the selected harmonic of cogging torque is reduced by optimizing the helical tooth angle. Standing...
In order to eliminate the identification error of permanent magnet flux linkage (PM flux linkage) due to the measurement noise and multi-parameters variation of permanent magnet synchronous motor (PMSM), the parameter sensitivity of PM flux linkage is first analyzed, then based on the analysis results, an online full rank identification method of PM flux linkage is proposed by the mutual updating...
In a two-stage on-board charger, the front-end PFC AC/DC converter with conventional dual closed-loop PI controller, which consists of a external voltage loop and a inner current loop, is used to perform ac/dc conversion and power factor correction. The main drawbacks are poor dynamic performance and insufficient anti-disturbance ability. Therefore, enhancing the dynamic performance of PFC AC/DC converter...
A model-free control scheme is proposed for a surface mounted permanent magnet synchronous motor (SMPMSM) drive system with parametric uncertainties and inverter nonlinearity. Using only the input and output data of system, the ultra-local model of SMPMSM system is first set up and the proposed ultra-local model is able to accurately identify the nonparametric model of SMPMSM system with the unknown...
The EBG structure have special electromagnetic properties such as high surface impedance and suppression of propagating surface currents within a frequency band. Fractal structure has two special properties: space-filling property and self similarity property which may help the antenna have good performance. In this paper, a new PIFA with fractal EBG structure as its ground will be investigated. The...
The reliability and fault-tolerant capability of electric drive systems is critical to electric vehicles (EV), therefore, the critical open-circuit fault and position sensor fault are focused to research for an interior permanent synchronous motor (IPMSM) drive system of EV. A convenient and switchable mathematical model of IPMSM drive system is first set up, and a new conversion matrix is been proposed...
Accurate measurement of FET gate resistance is needed to support technology development and to understand its impact on RF performance. This is especially true for high-K Metal Gate Fin FET technologies. Decreasing gate capacitance with each successive technology node has made gate resistance measurement increasingly difficult. This work presents a "Virtual De-Embedding" approach to the...
Due to the influence of technology and management mechanism, it is difficult to implement the Automatic Generation Control (AGC) in multi-area power system. Distributed Artificial Intelligence (DAI) presents a novel idea for coordination optimization control of multi-area AGC. In this paper, quick response characteristic of Superconducting Magnetic Energy Storage (SMES) and coordination skill of Multi-Agent...
40.5kV metal enclosed air insulation switchgear is a very important electrical device for electrical power system and industry customer. According to the main insulation dielectric used in switchgear, the switchgear can be classified into air-insulated and gas insulated devices. In fact, in the air-insulated switchgear, additional to the air used as insulation dielectric, also there are others insulation...
Large-scale documents reduction plays a critical role in document management organizing and document mining, etc, and the research is concentrated on two special aspects: the construction of document representation model and index optimization of feature space for similarity search. While the semantic gap and curse of dimensionality are still two open and tough issues. Motivated by this, in the paper,...
The input resistance of CMOS circuits is a measurable limit on the performance of typical static CMOS logic gates. A survey of measured data from five generations of CMOS technology including polysilicon oxynitride gate first stacks (P-SiON), high K metal gate first stacks (GF), and high K replacement metal gate stacks (RMG) shows a trend of increasing gate resistance. We show DC and RF measurements...
Power line inspection is essential work for the maintenance of electric grids. Besides manually inspecting power lines, which is still the main method, helicopters are also used for the inspection from the sky. In the recent years, unmanned flying systems were used for power line inspection in order to reduce the risk. In this paper, the design and application of SmartCopter, an unmanned autonomous...
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