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A printed loop monopole antenna with wideband circular polarization is presented. The wideband circular polarization is achieved by asymmetrical excitation of hemicycle ground plane and planar loop monopole antenna. The combined radiation provides a wide axial-ratio bandwidth spanning from 1.73to 3.10GHz (54.8%). A parametric study of the key geometric parameters is given for the better understanding...
The Doppler scale estimation based on Null subcarriers in underwater acoustic (UWA) orthogonal frequency division multiplexing (OFDM) communication is investigated, which is an optimization problem for finding extremum. The cost function constructed of the total energy of null subcarriers in ultra-wideband UWA channels is proposed. The frequencies of null subcarriers are calculated according to non-uniform...
To obtain information of the three-dimensional road roughness, a three-dimensional road roughness measurement system based on two-dimensional laser rangefinder was developed. In this paper, we described the composition and working principle of the three-dimensional road roughness measurement system, and designed its functional structure and hardware configuration. This measurement system can complete...
This wavelet theory is a powerful tool for dealing with nonlinearity. To start with basic principles of the nonlinear vibration equation, this paper proposed a nonlinear restoring force model in accordance with existing model characteristic, we derived wavelet perturbation solution of nonlinear vibration equation based on wavelet transform and perturbation methods. Finally, signal-degree-of-system...
In order to study the evacuation characteristics under complex building structure, an emergency evacuation model considering multi-exits was established based on cellular automaton in this paper, The distance from pedestrian location to the exit and pedestrians' density near exit were considered in the model, meanwhile, the exit door size is a key factor for exit choice during escaping. We simulated...
Many computer vision problems can be posed as learning a low-dimensional subspace from high dimensional data. The low rank matrix factorization (LRMF) represents a commonly utilized subspace learning strategy. Most of the current LRMF techniques are constructed on the optimization problem using L_1 norm and L_2 norm, which mainly deal with Laplacian and Gaussian noise, respectively. To make LRMF capable...
In this work, process variation effect (PVE), work function fluctuation (WKF), and random dopant fluctuation (RDF) on 10-nm high-K/metal gate gate-all-around silicon nanowire MOSFET devices using full-quantum-mechanically validated and experimentally calibrated device simulation are studied. The small aspect ratio device has greater immunity of RDF, while suffers from PVE and WKF.
In recent years, web-based attacks increase and become the top threat in cloud environments. To detect unknown web-based attacks, many studies resort to anomaly detection through analyzing web logs. This paper presents an anomaly detection approach, which includes a transforming model and a classifier model. The transforming model converts every entry into a vector, and every value in vector is obtained...
A new front-end readout circuit design using an adaptive amplifier is proposed by this study for magnetic and optical scales. The purpose of the integrated chip (IC) designed herein is to provide the magnetic/optical scales the capability of sensing translational or angular positions of an object in largely-varying amplitudes with high resolutions. Toward this end, a new front-end readout circuit...
This paper presents an obstacle avoidance method of escaping from obstacle zone based on maximum distance priority mechanism, aiming at the obstacle avoidance with limited local environmental information instead of known global environmental information. Acquiring local environmental information by laser range finder (LRF) which collects distance data between object and mobile robot, we use a method...
This study proposed an adaptive front-end readout circuit design for high resolution magnetic scales. The demonstration will provide the operation of magnetic scales, that can show the amount of displacement of magnetic scales by FPGA module. The adaptive front-end circuit can be sense three kind of input gain with FPGA module via magnetic scales movement. In the further, the visitors can experience...
Two radar engines targeting CW/FMCW/pulse structures have been reported in this paper for 24/26 GHz multi-standard applications. Temperature compensation, injection-locking PLL, and Butler matrix techniques have been adopted in this work to achieve full operation with remarkable performance.
For gear fault classification problem, most of fault diagnosis methods only use the sensor output signal to diagnose. For this reason, they can not reflect the system as a whole transmission characteristic and so inevitably there are limitations. a fault diagnosis method based on Volterra kernel, which uses input and output signal in gear system, is presented. The method uses the first order, second...
Online discussion forums make up a significant bulk in the type of opinion information that represents a valuable source for many real-world applications. However, conducting comprehensive opinion analysis of threaded discussions is a challenging task because it requires not only an aggregation of opinions over the multi-level thread structures, but also effective methods for exploring the complex...
Continuous Stirred Tank Reactor (CSTR) is a typical and high nonlinear process in process industry .It is difficult to control CSTR process. MPC is an advanced control strategy. But it is hard to tune the MPC parameters. A hybrid algorithm is presented to solve this difficulty and this algorithm is based on the immune clonal selection algorithm and sequential quadratic programming. The framework of...
With the evolution of technology and growth of economy, people's living style has gradually changed from Active-lifestyle into Sedentary-lifestyle. According to statistics, the ratio of students engaging in regular exercise has been declined with the increase in education. Under the long-term shortage of exercise, teenagers usually cannot develop regular exercise habits as soon as possible which has...
In this paper, a new common inductor current sharing method is proposed for multi-phase LLC resonant converter for high power application. Automatic current sharing is achieved by using a common resonant inductor for all the LLC resonant stages, by connecting the resonant inductors in each phase in parallel. The proposed method can automatically share the load current without any additional circuit...
In computer and telecommunication power supplies, the front end DC-DC stage is required to operate with a wide input voltage range to provide hold up time when AC voltage fails. Conventional LLC converter serving as the DC-DC stage is not suitable for this task, as the normal operation efficiency at 400Vin will be penalized once the converter is designed to achieve high peak gain, i.e. the wide input...
Recently, the industrial wireless protocols have been widely used around the world. However, the unreliable communication media between the sensors and the central controller renders the wireless signal channel vulnerable to many attacks. Various efforts have been devoted to study the influence of specific malicious attacks from the aspect of theoretical investigation based on different assumptions...
For low output voltage application, a half-bridge LLC resonant converter family with synchronous rectifier (SR) that has a boost pulse width modulation (PWM) converter characteristic for hold-up state operation is proposed in this paper. In proposed converters, an auxiliary switch (or an auxiliary switch and a diode) is added at the primary side to provide the charging branch for series resonant inductor...
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