摘要：
Compressed Sensing (CS) is an emerging theory which can sample the sparse signal or compressible signal via sub-Nyquist sampling rate and reconstruct the original signal with small amount of measurements. Since speech signal is sparse in Discrete Cosine Transform (DCT) domain, a kind of adaptive Bayesian Compressed Sensing (BCS) based on speech signal is proposed in this paper. In the one hand, our proposed method exploits the difference of energy within different speech frame to allot measurements adaptively for each speech frame aim to promote the quality of recovery speech signal. In the other hand, the position information of sparse coefficient in each speech frame is also utilized by our proposed method to recover its neighboring speech frame for reducing the recovery time of speech signal. The experimental results prove that our proposed method is surely effective and practical.
摘要：
In this paper, a new readout structure for monolithic uncooled focal plane array is proposed. The proposed readout structure contains several or dozens of readout integrated circuits modules and these modules work independently and output their pixel signals concurrently. For monolithic uncooled focal plane array, each module of readout integrated circuit can output its infrared sensing voltage signals at its maximum output speed, and the whole focal plane array has multiplexed outputs at a time. This kind of readout structure is appropriate for ultra-large-scale monolithic uncooled focal plane array and can be applied to future uncooled focal plane arrays.
作者机构：
[Zheng, Changzheng; Xie, Yan] Wuhan Polytech Univ, Sch Elect & Elect Engn, Wuhan, Hubei, Peoples R China.;[Li, Mu] Wuhan Nari Ltd Liabil Co, State Grid Elect Power Res Inst, Wuhan, Hubei, Peoples R China.
会议名称：
2nd International Conference on Advances in Materials, Mechatronics and Civil Engineering (ICAMMCE)
会议时间：
JAN 19-20, 2017
会议地点：
Guangzhou, PEOPLES R CHINA
会议主办单位：
[Xie, Yan;Zheng, Changzheng] Wuhan Polytech Univ, Sch Elect & Elect Engn, Wuhan, Hubei, Peoples R China.^[Li, Mu] Wuhan Nari Ltd Liabil Co, State Grid Elect Power Res Inst, Wuhan, Hubei, Peoples R China.
会议论文集名称：
AER-Advances in Engineering Research
关键词：
Safety protection;Live working;Transmission line
摘要：
In recent years, in order to save line corridors and reduce the scope of demolition, some new transmission modes for high voltage AC and DC power transmission line are proposed. According to the characteristics of the parallel transmission line, this paper studies the distribution characteristics of the electric field intensity of multi circuit parallel transmission lines and the single circuit transmission line. Comparing and analyzing the simulation results of the electric field strength, the safety measures for live working of similar to 500kV DC transmission line with multi circuit parallel transmission lines is put forward. That is the electric field protective equipment and measures used in the live line work of the +/- 800kV HVDC single circuit line can meet the requirements of the live operation of the +/- 500kV HVDC multi-circuit transmission line.
摘要：
Underwater sonar imaging is a significant means for a variety of maritime work. However, the sonar images are corrupted by signal dependent speckle noise, which restricts the potential practical applications. In this paper, we propose a novel variational approach that addresses the adaptive sonar image denoising problem. To accurately describe the signal dependent characteristic of noise for real sensors, we utilize a generalized noise model, which can be adapted to represent various types of noise. With the generalized noise model, we formulate the denoising problem via a variational approach. Finally, we present a modified primal and dual method to efficiently solve the variational minimization problem. Experimental results on both simulated and real data validate the effectiveness and efficiency of our method.
摘要：
Warm-up time, which is for the OCXOs to get the nominal frequency stability, is a critical factor for the application of OCXOs. In most OCXOs, the temperature sensing and control method is passive involving heating resistors or power transistors. This kind of configuration makes the normal warm-up time around/above 3 minutes, which is not suitable for the applications requiring quick start and test scenarios. In order to improve the warm-up time, this paper presents a new active temperature sensing and control method by employing a thermoelectric cooler (TEC) to shorten the warm-up time. Test results show the warm-up time could be less than 1 minute and the temperature stability of the OCXO with the TEC is better than the one without the TEC.
关键词：
Wind Energy (WE);Coordination and Optimization Control (CnOC);Wind Farms (WFs);Wind Turbine (WT);Wind Rose (WR);Wind Power (WP);Tip Speed Ratio (TSR)
摘要：
This paper focuses on Wind Farms (WFs) optimization and Wind Energy (WE) systems of Luxembourg. The overview of wind resources in all WFs is described and a class of Improved Generalized Multiple Wake Model (IGMWM) for Coordination and Optimization Control (CnOC) of WFs are presented. Based on Wind Power (WP) assessment of WFs, the statistical methods are used to model the distribution of Wind Speed (WS) and Wind Direction (WD). Finally, some simulation figures about Wind Rose (WR) and WF optimization demonstrate the WP in detail. These assessments are expected to enhance the exploitation and utilization of WP in WFs of Luxembourg.
摘要：
Non-destructive determination of TVB-N content in beef using hyperspectral imaging(HSI) technique was evaluated.In order to create a robust model to predict the TVB-N content in beef,partition of samp
摘要：
In this paper, an Improved Frandsen Wake Model(IFWM) and its variation model-Improved Frandsen Normal Distribution Wake Model(IFNDWM) for Wind Farms(WFs) have been presented and analyzed exhaustively with mathematic forms. The comparisons of these two ditlerent wake models of WFs also have been expounded. Meanwhile, experimental comparisons of both Wake Models are studied. Further, focused on the WFs of Luxembourg, the statistical methods are used to model the distribution of Wind Speed(WS) and Wind Direction(WD). Finally, some simulations are provided to test and verify their effectiveness and correctness of these models. Wind Rose(WR) and wind resources demonstrate Wind Power (WP) in full. These assessments are expected to enhance WP exploitation and utilization in WFs of Luxembourg.
摘要：
Due to the poor spectrum utilization in time and space, the spectrum in cognitive radio is not only sparse but clusters in blocks in many situations. Based on the fact, a novel Bayesian compressed sensing algorithm for wideband spectrum sensing is proposed. In our proposed framework, firstly, the original signal should be sampled with sub-Nyquist sampling rate. Secondly, the clustering of the spectrum molded by many block structures is also utilized to increase the accuracy of spectrum sensing. Lastly, with a variational Bayesian inference, the experimental results show the validity and advantage of our proposed approach.
摘要：
Parameter convergence is desirable in adaptive control as it brings several attractive features, including accurate online identification, exponential tracking and robust adaptation without parameter drift. However, a strong persistent-excitation (PE) condition has to be satisfied to guarantee parameter convergence in the conventional adaptive control. This paper proposes a novel composite learning technique to guarantee parameter convergence without the PE condition for a class of affine nonlinear systems with parametric uncertainties. In the composite learning, a time-interval integral is utilized to construct a prediction error, a linear filter is applied to estimate the derivative of a tracking error, and both the tracking error and the prediction error are employed to update parametric estimates. It is proven that the closed-loop system achieves semiglobal practical exponential stability by an interval excitation (IE) condition which is much weaker than the PE condition. The effectiveness of this approach has been illustrated by a numerical example of aircraft wing rock control.
摘要：
Composite adaptive control(CAC),an integrated direct and indirect adaptive control strategy,has been broadly applied to robots due to its superior control performance.This paper focuses on robustness
摘要：
Hydrogenated amorphous silicon carbide thin films (a-SiC: H) were deposited by decomposition of SiH4 and CH4 gas mixtures at 200 degrees C. Chemical bonding configuration measurements by Fourier transform infrared absorption spectroscopy show that there are SiHn (n=1,2,3), C-SiH, non-hydrogen Si-C, Si-CH3, and CHn (n=1,2,3) radicals in the as-grown sample. Raman scattering measurement reveals a broad peak located at about 479.4 cm(-1) and a weak protuberance at 970.6 cm(-1). These demonstrate that there aren't any crystalline nanoparticles and the sample is in amorphous feature.
摘要：
This paper introduced modular multi-level converter (MMC), which could enhance the voltage and power level by sub-converter modules in series and was easy to extend to any level of output. Its structure and working mechanism were described. By analyzing the energy transfer performance of STATCOM based on MMC working conditions in the compensation, a comprehensive compensation control strategy was proposed based on direct current control mode. By analyzing the higher harmonic components circulation generated by the inconsistencies in the three-phase upper and lower arm voltage, a loop control strategy is proposed for the suppression of the circulation in the arms of the M-STATCOM. The simulation results show the strategy has a better tracking precision and response speed for the compensation control.
摘要：
Conventional surveying method could not solve the problem of detecting building's whole deformation in a short time, including in particular flatness and inclination values of the surface of the building. Aiming at this problem, this paper introduce a method to solve it based on terrestrial laser point cloud, first step is fitting point-cloud datum to point-cloud model for reducing random errors in original point cloud, and then calculating the distance between original points to fitting model on homogeneous region and upon determining root mean square error about this distance as a flatness index. The second step, calculating the angle between model and reference plane (such as a horizontal or vertical), and which will be used as the inclination value of a building surface. Project tests proved the effectiveness of this method.
摘要：
A social network is a social structure made up of a set of social actors (such as individuals or organizations) and a set of the dyadic ties between these actors. By contrast, for the fixed time duration the size of digital video would be much bigger than that of digital sound. Consequently, providers of social network services can offer real-time chatting among users which could offer satisfactory experiences for users. As one of the most popular content-based social network services (SNS), chatting service plays an important role in current big data era. Also average data packets' transmission via networks is another significant traffic. So how to offer satisfactory Quality of Service (QoS) for users is the key problem which will be solved for SNS provider. For real time communication among users, end-to-end time delay seems to be critical in user's experience. Therefore modeling and evaluating social network systems is an important and urgent issue which offers quantitative basis of SNS with high quality for users. For social network system, the scalability and robust are important for both service provider and users under the circumstance of a large number of users. On the basis of performance evaluation of social network system of one user case, we construct the SPN model and conduct numerical analysis to discover and report the performance with the addition of users. By taking hybrid traffic containing voice and data into account, this paper constructed a Stochastic Petri Net (SPN) model for data and ON/OFF voice traffic for social network system. Then, average time delay of the system was analyzed and model-based simulation is conducted with Stochastic Petri Net Package (SPNP) 6.0. Furthermore, for different parameters of burst rate, idle rate, number of data packets, traffic load and buffer size, variation trends on average time delay are derived thereby. On the basis of the work in this paper, further research on heterogeneous objects of social network systems can be carried on. A social network is a social structure made up of a set of social actors (such as individuals or organizations) and a set of the dyadic ties between these actors. By contrast, for the fixed time duration the size of digital video would be much bigger than that of digital sound. Consequently, providers of social network services can offer real-time chatting among users which could offer satisfactory experiences for users. As one of the most popular content-based social network services (SNS), chatting service plays an important role in current big data era. Also average data packets' transmission via networks is another significant traffic. So how to offer satisfactory Quality of Service (QoS) for users is the key problem which will be solved for SNS provider. For real time communication among users, end-to-end time delay seems to be critical in user's experience. Therefore modeling and evaluating social network systems is an important and urgent issue which offers quantitative basis of SNS with high quality for users. For social network system, the scalability and robust are important for both service provider and users under the circumstance of a large number of users. On the basis of performance evaluation of social network system of one user case, we construct the SPN model and conduct numerical analysis to discover and report the performance with the addition of users. By taking hybrid traffic containing voice and data into account, this paper constructed a Stochastic Petri Net (SPN) model for data and ON/OFF voice traffic for social network system. Then, average time delay of the system was analyzed and model-based simulation is conducted with Stochastic Petri Net Package (SPNP) 6.0. Furthermore, for different parameters of burst rate, idle rate, number of data packets, traffic load and buffer size, variation trends on average time delay are derived thereby. On the basis of the work in this paper, further research on heterogeneous objects of social network systems can be carried on.
关键词：
ER fluids;Electrooptical effect;Light transmission;Photocurrent
摘要：
An investigation was made to observe the electrooptical effect of ER fluids prepared with starch and silicon oil through experiments, in which the transmitted light intensity of ER fluid samples with different concentration were measured under varying external electric field. The results show that the detected photocurrent increases first and then decreases with the increasing of electric field; the sample with higher concentration reaching the peak value of photocurrent requires a lower external electric field, but it has an opposite effect for the sample with lower concentration. The electric field has better tunability for the refractive index of sample with lower concentration than for that with higher concentration.
摘要：
Visualizing mechanical strain/stress changes is an emerging area in structural health monitoring. Several ways are available for strain change visualization through the color/brightness change of the materials subjected to the mechanical stresses, for example, using mechanoluminescence (ML) materials and mechanoresponsive polymers (MRP). However, these approaches were not effectively applicable for civil engineering system yet, due to insufficient sensitivity to low-level strain of typical civil structures and limitation in measuring both static and dynamic strain. In this study, design and validation for high-sensitivity strain visualization using electroluminescence technologies are presented. A high-sensitivity Wheatstone bridge, of which bridge balance is precisely controllable circuits, is used with a gain-adjustable amplifier. The monochrome electroluminescence (EL) technology is employed to convert both static and dynamic strain change into brightness/color change of the EL materials, through either brightness change mode (BCM) or color alternation mode (CAM). A prototype has been made and calibrated in lab, the linearity between strain and brightness change has been investigated.
