In this paper a compact and wideband planar inverted-F antenna (PIFA) with metamaterial loaded on the ground plane is proposed. The metamaterial units, composed of an array of Jerusalem crosses PEC structure, improve ...
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In this paper a compact and wideband planar inverted-F antenna (PIFA) with metamaterial loaded on the ground plane is proposed. The metamaterial units, composed of an array of Jerusalem crosses PEC structure, improve the performance of the antenna and cause a special characteristic of backward radiation. Simulation results show that this novel antenna has a bandwidth of 49.4%, which is from 2.56 GHz to 4.24 GHz. Compared to a conventional PIFA simulated in this paper, the proposed antenna has a reduction of 91% in dimension. And the antenna has a gain over 3 dB within the whole bandwidth.
An review on the development and extrodinary properties of left-handed materials is first *** on the current research,left-handed materials is applied to the microstrip antenna *** miniaturized antenna are designed by...
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An review on the development and extrodinary properties of left-handed materials is first *** on the current research,left-handed materials is applied to the microstrip antenna *** miniaturized antenna are designed by using the left-handed materials,which makes futhur miniaturization of microstrip antenna possible.
An evocative solution for the brachistochrone problem is presented by Euler-Lagrange equation. The solution of brachistochrone problem by variational approach i.e. Euler-Lagrange equation leads to the curve of a cyclo...
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An evocative solution for the brachistochrone problem is presented by Euler-Lagrange equation. The solution of brachistochrone problem by variational approach i.e. Euler-Lagrange equation leads to the curve of a cycloid also known as brachistochrone curve. In this paper the exactness of the brachistochrone curve is verified through simulated studies in MATLAB, taking into cognizance different other curves viz. straight line and parabola along with cycloid. By computing the time taken by the bead in traversing the path between two points under gravity along all the curves considered, it is seen after comparison that the time taken along the cycloid is the least.
High-end CNC machine tool is the main production equipment in the modern manufacturing industry, and its stability and reliability on operation state is directly linked to the machining accuracy and efficiency. In ord...
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High-end CNC machine tool is the main production equipment in the modern manufacturing industry, and its stability and reliability on operation state is directly linked to the machining accuracy and efficiency. In order to guarantee effectively the reliable stable and safe operation, the test study is conducted to the data acquisition and database based on high-end CNC machine tool. In this paper, the study of high-end CNC machine tool is focused on building the condition monitoring and test platform with the typical functional components. The method of data acquisition is presented, knowledge base and knowledge model are designed, the test platform of remote network data acquisition is built and real time data will be transferred to different client. A key technology is presented to reveal the dynamic performance of failure development and accuracy degradation mechanism, and the influential factors leading to failures.
Solar photovoltaic(PV) array power generation, as a utilization form of solar energy, has been widely applied in solar generator systems throughout the world. Effective guarantee of PV array normal power generation, r...
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Solar photovoltaic(PV) array power generation, as a utilization form of solar energy, has been widely applied in solar generator systems throughout the world. Effective guarantee of PV array normal power generation, rapid and accurate detection of fault location and the prediction of fault occurrence are of great significance. This paper, based on the analysis of solar photovoltaic power generation performance, raises new voltage and current detection method. The original current and voltage detection method can not distinguish the environmental factors which causes the decrease in power generation capacity. This new test method can overcome such defect, and can accurately judge the location where cell array fault occurs; this technology is very important to safe and reliable operation of solar photovoltaic generation system and the improvement of power generation efficiency.
Fault prediction is the key technology to guarantee the safe operation of large mechanical equipment,and fault feature extraction is a key issue in fault prediction. To extract fault feature from the non-stationary fa...
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Fault prediction is the key technology to guarantee the safe operation of large mechanical equipment,and fault feature extraction is a key issue in fault prediction. To extract fault feature from the non-stationary fault signals, this paper proposed a fault feature extraction method using lifting wavelet packet, and constructed the fault feature vector of optimal energy. The fault feature extraction analysis shows that the proposed method can highlight the energy change within the optimal decomposition frequency band, and effectively reflect the fault status.
A high-order nonsingular terminal sliding mode (NTSM) optimal control scheme for an uncertain two-link flexible manipulator system is proposed with considerations of both problems of non-minimum phase and chattering. ...
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A high-order nonsingular terminal sliding mode (NTSM) optimal control scheme for an uncertain two-link flexible manipulator system is proposed with considerations of both problems of non-minimum phase and chattering. Through system decomposition into an input-output subsystem and a zero dynamic subsystem by regular form technique, the controllable minimum phase characteristic is achieved, and then a third order NTSM controller is designed to realize fast convergence of the input-output subsystem, as well as to suppress the undesirable chattering. Meanwhile, the stability of zero dynamic subsystem is checked and its control property is optimized by a genetic algorithm around equilibrium points. Simulation results are presented to validate the control scheme.
Many advanced driver assistance systems (ADAS) and autonomous vehicles require 3D information available from (stereo) camera systems. The corresponding task of estimating disparity or optical flow is computationally d...
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Many advanced driver assistance systems (ADAS) and autonomous vehicles require 3D information available from (stereo) camera systems. The corresponding task of estimating disparity or optical flow is computationally demanding, so meeting real-time update rates at high image resolutions has proven to be challenging. Modern parallel hardware seems suitable for this task only if its processing power can be efficiently accessed by parallel software implementations. In this paper we present a case study comparing different hardware platforms by two variants of block matching-based estimation. These platforms include two x86-compatible multicore systems, a graphics processing unit (GPU) and a 64-core embedded design. We introduce relevant features of each architecture and describe their effects on the applied algorithms, parallelization approaches and implementations. Target platforms are evaluated concerning computational performance, energy efficiency and programmer productivity.
In this paper, a broadband monopolar patch antenna is proposed. The epsilon negative (ENG) zeroth-order resonator (ZOR) is used to broaden the bandwidth of a monoplar patch antenna by combining two resonances together...
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In this paper, a broadband monopolar patch antenna is proposed. The epsilon negative (ENG) zeroth-order resonator (ZOR) is used to broaden the bandwidth of a monoplar patch antenna by combining two resonances together. The ENG ZOR antenna shares the patch and the ground plane with the monopopar patch antenna. The impedance bandwidth of the proposed antenna ranges from 0.89 to 3.95 GHz, and the gain of it is above 4.1 dB. This antenna has monopole-like radiation patterns over the whole bandwidth range.
This paper presents the design and analysis of a bandwidth extended and compact antenna based on CRLH TL (Composite Right/Left Handed Transmission line) with slot loaded. The CRLH TL is realized by the periodic placed...
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This paper presents the design and analysis of a bandwidth extended and compact antenna based on CRLH TL (Composite Right/Left Handed Transmission line) with slot loaded. The CRLH TL is realized by the periodic placed EBG (Electromagnetic Band Gap) unit, the patch and the probe can be regarded as the series capacitance and shunt inductance respectively. Then the microstrip antenna is supposed to resonant in some certain conditions. Combine the left handed resonance frequency with the extra resonance mode, which is stimulated by the loaded of the slots, the bandwidth of the antenna can be extended efficiently. The full-analysis of the antenna is simulated. And the results show that the relative operation frequency bandwidth of the proposed antenna is 9.3% and the overall size of the antenna is only a quarter of wavelength. Besides, the radiation pattern of the antenna in the entire impedance matching band keeps unchanged, which means the radiation bandwidth is in step with the impedance bandwidth.
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