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1.
提出了一种基于能量对称度(ES)参数的基音检测方法.先通过波峰检测和对称度检测粗略估计语音的基音,再根据ES参数得到最佳的语音基音。实验证明此方法不仅具有实时性而且具有很高的准确性,而且不存在延时问题.是一种适合于单片机实现的语音信号处理方法。  相似文献   
2.
In order to investigate the failure process of brittle rock under triaxial compression through both experimental and numerical approaches, the particle simulation method was used in numerical simulations and the simulated results were compared with those of the experiment. The numerical simulation results, such as fracture propagation, microcrack distribution, stress-strain response, and damage patterns, were discussed in detail. The simulated results under various confining pressures (0-60 MPa) are in good...  相似文献   
3.
The damage process of fractured rock mass showed that the fracture in rocks induced roof collapse in Yangchangwan Coal Mine,China.The rock mass was particularly weak and fractured.There occurred 6 large-scale dynamical roof falls in the excavation disturbed zone (EDZ) with the collapsing volume of 216 m3.First,the field detailed geological environment,regional seismic dy-namics,and dynamic instability of roadways were generally investigated.Second,the field multiple-index monitoring measurements for detecting the deep delamination of the roof,convergence deformation,bolt-cable load,acoustic emission (AE) characteristic pa-rameters,total AE events,AE energy-releasing rate,rock mass fracture,and damage were arranged.Finally,according to the time-space-strength relations,a quantitative assessment of the influence of rock-mass damage on the dynamic roof instability was accomplished.  相似文献   
4.
Incoherent scatter spectra due to HF heating in the low ionosphere region   总被引:2,自引:0,他引:2  
The electron velocity distribution function and the incoherent scatter spectra during ionospheric heating in low ionosphere region are presented with consideration of the elastic collision between electrons and neural particles and the excitation of rotation energy level. The effects of pump frequency and electric fields on the spectra are discussed. With the increase of electric field, the non-Maxwellian feature is enhanced, and with the increase of heating frequency, the non-Maxwellian feature is weakened. The non-Maxwellian factor will bring a large error in ionosphere parameters, which must be considered in the inversion. Supported by the National Natural Science Foundation of China (Grant No. 40310223), the National Key Laboratory of Electromagnetic Environment (LEME), and National Key Technologies R&D Program of China (Grant No. 2006BAB18B06)  相似文献   
5.
Research on indoor experimentation of range SAL imaging system   总被引:1,自引:0,他引:1  
By means of advantages of both SAR and lidar, the combination of the techniques of (inverse) synthetic aperture and lidar makes it possible to obtain high resolution 2-D image. In this paper, an indoor experimental system of inverse synthetic aperture lidar imaging is given and a processing approach is presented. The given system is in the mode of lidar system with separated receiver and transmitter, which can effectively eliminate the jamming from the lens or/and the intersection between two optic fibers. ...  相似文献   
6.
Fault diagnosis of rolling mills, especially the main drive gearbox, is of great importance to the high quality products and long-term safe operation. However, the useful fault information is usually submerged in heavy background noise under the severe condition. Thereby, a novel method based on multiwavelet sliding window neighboring coefficient denoising and optimal blind deconvolution is proposed for gearbox fault diagnosis in rolling mills. The emerging multiwavelets can seize the important signal proce...  相似文献   
7.
计算机网络技术的出现,全球信息化改变着人们的生活方式,世界各国高度重视发展电子政务,它是一个国家及城市竞争力水平的标志之一.在这样严峻的社会形势下,建立一个高效的电子政务系统是十分必要的.首先,分析了建立电子政务系统的必要性、特点、功能;然后,提出了电子政务系统的体系模型,设计出了功能结构图和网络结构图,详细地描述了方案思路;最后,把此模型应用到商洛市旅游行业中,经过调查数据研究分析,政务系统的出现给旅游业带来巨大的变化,整个城市的经济、影响力大幅度上升.  相似文献   
8.
Let SFd and Πψ,n,d = { nj=1bjψ(ωj·x+θj) :bj,θj∈R,ωj∈Rd} be the set of periodic and Lebesgue’s square-integrable functions and the set of feedforward neural network (FNN) functions, respectively. Denote by dist (SF d, Πψ,n,d) the deviation of the set SF d from the set Πψ,n,d. A main purpose of this paper is to estimate the deviation. In particular, based on the Fourier transforms and the theory of approximation, a lower estimation for dist (SFd, Πψ,n,d) is proved. That is, dist(SF d, Πψ,n,d) (nlogC2n)1/2 . T...  相似文献   
9.
双权值网络在电源管理中的应用研究   总被引:1,自引:0,他引:1  
本文阐述了一种基于双权值神经网络的数据拟合学习算法,并在此基础上提出一种将其应用于系统电源管理的新算法.双权值神经网络通过学习系统中的历史空闲段长度,对未来将产生的空闲段长度进行预测,使得系统能够根据预测结果自动切换其运行的状态,从而达到降低功耗的目的.实验证明:较传统的电源管理算法,本算法能进一步提高系统的正确关断率、降低系统在空闲时段的功耗.  相似文献   
10.
A spatial orthogonal allocation method is devised for multirobot tasks allocation.A 3D space model is adopted to describe exploration mission;meanwhile spatial orthogonal tentative technology is utilized to update the attractor position for load balance.Heterogeneous interactive cultural hybrid architecture is proposed to solve a robot route planning problem;it utilizes good-point-set to initialize population spaces,redefine novel evolution model and particle evolution ability,and introduce near-neighbor lo...  相似文献   
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