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This paper presents a method to deploy the virtual router on the network node of OpenStack platform by using the networking VPP (Vector Packet Process) as the virtual router. This method is dedicated to high-speed network tasks. It runs on the DPDK (Data Plane Development Kit) user space, does not use the kernel driver to obtain packets from the hardware. The sending, receiving and processing of messages are implemented in user space, which means less kernel calls, less context switching and faster processing. In this method, the computing nodes and network nodes are deployed separately, and the user mode forwarding work of network node data plane is transferred to VPP. VPP is used to realize the function of three-layer routing and forwarding, which can accelerate the east-west traffic of VLAN network, also can improve the performance of three-layer routing and forwarding by 3–5 times. By this method, the bottleneck of OpenStack network can be eliminated, the performance of data center network can be further optimized.

This paper investigates the physical layer security of non-orthogonal multiple access (NOMA) with decode-and-forward (DF) relays in underlay cognitive radio (CR) network. Secondary transmitter communicates with legitimate users via the aid of relays, while the eavesdroppers try to intercept the message. To safeguard legitimate communications against eavesdropping, the joint of artificial-noise (AN) and relay selection (RS) is applied. We derive the secrecy outage probability (SOP) and the secrecy throughput to evaluate the secrecy performance. In addition, the asymptotic floor of SOP is derived. Numerical results verify that cooperative NOMA in underlay CR (CRNOMA) significantly outperforms the conventional orthogonal multiple access (OMA) in underlay CR network (CROMA) in terms of the secrecy outage performance. Furthermore, the effect of some critical parameters on the secrecy performance has been studied.

Accurate estimation of reverberation time T_60 proved to have a positive effect on the automatic speech recognition (ASR) used in the voice-controlled devices and the reconstruction of the acoustic field. Recently, researchers have proposed some algorithms to estimate T_60. However, few of them directly use the spatial information about the acoustic environment contained in the speech for accurate T_60 estimation. We propose a deep learning approach as a regression problem to use binaural reverberant speech generated by the clean speech convolved with simulated Room Impulse Response (RIR) to estimate T_60. Adaptive cIRM estimator firstly estimates the complex Ideal Ratio Mask (cIRM), which is strongly correlated with T_60, and then a CNN-based T_60 estimator is used to estimate T_60 with cIRM. The experimental results show that our proposed approach outperforms the state-of-the-art method of T_60 estimation.

The content of Sio 2 in rocks is an important indicator of magmatic rock classification, and quartz vein is the main indicator of field prospecting. In this paper, 60 rock samples from USGS (U.S. Geological Survey), JPL (Jet Propulsion Laboratory) and JHU (Johns Hopkins University) are used to resample the thermal infrared band to the ASTER thermal infrared band to study the emissivity characteristics relationship with Sio 2 content in the thermal infrared band (8-15μm). Correlation analysis shows that the maximum negative relationship between the Sio 2 content and the logarithmic transformation ln(bl3/bl2) spectrum of the ASTER band is -0.873, and the maximum positive correlation coefficient between Sio 2 content and logarithmic transformation ln(bl3)/ln(bl2) of ASTER band is 0.793, which indicates that the correlation between Sio 2 content and ASTER thermal infrared band emission spectrum is better. Five regression equations were established by multivariate stepwise regression method and partial least squares regression method. The inversion of Sio 2 content in surface rocks in Lin xi area of Inner Mongolia was carried out by ASTER thermal infrared band. This study has important reference significance for the application of thermal infrared remote sensing to extract Sio 2 content in surface rocks and to divide lithology and prospecting.

In this paper, we propose an end to end model for keyword spotting(KWS) with densely connected convolutional network(DenseNet) and the integration of Short Time Fourier Transform(STFT) which aims to extract utterances from raw waveform directly. Furthermore, we investigate the efficiency of adaptive and trainable window function in the task of keywords spotting. Using the recently-released Google Speech Commands Dataset as our benchmark. Our DenseNet implementation significantly outperforms previous neural networks based KWS system in terms of accuracy.

Voice activity detection (VAD) is a very challenging problem in adverse acoustic environments (e.g. far-field and conditions with different types of noise). In this paper, we proposed a Gaussian mixture model (GMM) for log-energy distribution of noise and (noisy) speech, where the distribution of these two components can be self-adapting in non-stationary circumstances. An adaptive threshold based on the GMM parameters of these two components represents a reasonable bound between noise and speech, which can lead to an accurate VAD in various noise conditions. To further improve speech hit rate (SHR) and non-speech hit rate (NHR), some constraints are introduced to this proposed GMM for reliability. Experimental results demonstrate that the proposed method yields remarkable performance for SHR and NHR.

Hierarchy is a fundamental characteristic of many complex systems. The methods of structural information have been taken as a prospective way for quantifying dynamical network complexity. This paper based on the study of the high-dimensional natural structural information entropy in networks. And then propose a new similarity District Structural Information (DSI) index, which takes the characteristics of network districts into consideration, to analyze the complexity of dynamical network districts. Based on the method, this paper apply the district structural information to explain the equilibrium problem in real-world networks. And take the Beijing traffic network and its districts to complete experiments that demonstrate the DSI index can reflect the equilibrium of the network and the districts effectively.

Sound rendering are frequently used to enhance the sense of immersion in virtual environments and multimedia applications. For this purpose, this paper proposes a ray tracing method based on equal-area distribution to simulate room impulse response (RIR). It is efficient and accurate to get the direction of arrival of the direct sound and early reflections. An equal-area distribution was adopted in the process of the sound source emitting. In order to optimize the sound source directivity, the direct sound and early reflections of RIR were mainly concerned. In our experiment, the RIR produced by ROOMSIM was set a reference. In addition, Monte Carlo method of equal-angle distribution was also presented as a comparison. Our proposed equal-area ray tracing (EART) can get a better result for early reflection and later reverberation.

This paper proposes an improved structural similarity method for audio quality assessment, which is Structural Similarity Analysis of Modulation (SSAM). Different from original structural similarity index measure, we introduce the analysis of structural similarity of modulation together with Computational Auditory Signal-processing and Perception (CASP) model. Audio features from CASP are extended to three dimensions: time, frequency and modulation spectrum. The combined architecture of ITU-R BS.1387-1 and proposed SSAM is given in this paper. Our proposed estimation system not only shows highly correlated with subjective results but also overcomes the shortage of ITU-R BS.1387-1 that only suitable for small impaired audio.

Frequent Itemsets are the sets that most likely occurring together. This paper propose a high efficient implementation for frequent itemsets generation and Support calculation based on a systolic array architecture through only one scan of the database. A parallel item-delivering method is introduced to accelerate the generation procedure. Analysis of simulation results illustrates that our method is much more efficient than the software algorithm and other hardware implementations.

Measurement of audio quality is of fundamental importance for numerous speech and audio processing applications, where the goal of quality assessment algorithms is to evaluate the quality in agreement with human's subjective feelings of audio quality. This paper includes a brief summary of the development of intrusive and non-intrusive audio quality assessment algorithms and outlines recent advancements, especially some new topics to be investigated presently. Moreover, according to the existing problems in this field, discussion of the future trend and challenges is also given.

In this paper, we propose an efficient algorithm to piecewise linear approximation of logarithm for the possible application to graphics physics simulation. Compared to the traditional approximation of logarithm methods, our algorithm produce a maximum relative error flatten distribution in all intervals, the maximum relative error can be set according to our difference accuracy needs. Simulations of our methods have been conducted in Matlab to verify correctness. Besides, we further present the hardware implement. Comparison simulation showed that our algorithm is superior to state-of-art logarithm conversion for stimulation accuracy.

3D graphics hardware acceleration has become more and more important in mobile devices. In the paper, we review some triangle rasterization algorithm previously. On that basis, we propose a novel triangle rasterization algorithm — midpoint traversal, which reduce the number of traversal points and improve the efficiency of graphic acceleration. At last, we use FPGA to implement the algorithm, drawing a conclusion: in the equality resource, compared with others triangle rasterization algorithm based edge function, the midpoint traversal can improve the efficiency.

This paper propose a high performance algorithm for logarithm approximation. A piecewise linear interpolation with non-uniform partition is introduced to produce a flatten error distribution. Base on error flatten algorithm our method can produce greatly more accurate results than state-of-art logarithm approximation. Our proposed logarithm conversion is further optimized for hardware implementation. Analysis of simulation results in Matlab and hardware resources in FPGA illustrate that our method are superior or comparable to state-of-art logarithm conversion for graphics hardware.

This paper proposed an improved audio quality metric via circular and flexible overlap. Based on the Power Spectrum Estimation via circular overlap, we use a novel circular overlap sub-frame to assess highly impaired audio. The relationship between the fraction of overlap and the metric of audio quality is also examined, and it has been proven that the accuracy of audio quality assessment increased with the fraction of overlap. By integrating circular and flexible overlap into ITU-R BS.1387, which is also known as Perceptual Evaluation of Audio Quality, our method can be applied to the quality assessment of highly impaired audio.

With the widely used of mobile devices, such as cellular phone, personal digital assistant (PDA), mobile navigator, personal multimedia player (PMP), 3D graphics are becoming key to mobile device experience. 3D graphics hardware acceleration has become more and more important in mobile devices. In the paper, we review some triangle rasterization algorithm previously. On that basis, we propose a novel triangle rasterization algorithm - midpoint traversal, which reduces the number of traversal points and improves the efficiency of graphic acceleration. At last, we use FPGA to implement the algorithm, drawing a conclusion: in the equality resource, the midpoint traversal can improve the efficiency.

With the demand of real time rendering of large scale of filed scenes, which require the graphic's processing unit that have the features of high efficiency and low power. the rasterization of graphics is a stage of compute intensive and is a key part to raise the system performance. In this paper, I improve the “CENTROL LINE” rasterization, is the main method for designing VLSI, and focus on the parallel processing, which is geared to hardware implementation. In order to verify the function of this improved algorithm, Matlab is used to simulate the algorithm and was implemented in the FPGA

This paper proposes a novel fragile watermarking scheme for audio content authentication. The chaotic mapping based watermark information is embedded in the principal component of the detail wavelet coefficients of the host audio based on the instantaneous mixing model of independent component analysis system. The watermark can be extracted with Fast ICA technique, blindly. Experimental results demonstrate that the proposed scheme achieves excellent transparency, good fragility, and accurate tampering detection.

This paper presents an efficient convolution technique in Modified Discrete Cosine Transform (MDCT) domain. It can be used to accomplish Head-Related Transform Function (HRTF) based binaural rendering. The MDCT and HRTF are firstly represented in a polyphase filter structure and further derived to a z-transform matrix representation. Based on the property of similarity between diagonal entries of filtering matrix and spectrum of HRTF, we presented a Dynamic Adjacent Elements Optimization (DAEO) for fast convolution of HRTF in the MDCT domain. Experimental results show that our algorithm greatly reduces the computational complexity, and maintains equal quality. The complexity analysis of virtual surround processing methods indicates that our filtering algorithm of HRTF consume minimal calculation, which is particularly suitable for audio compressed in MDCT format.

With the widely development of consumer electronics, 3D graphics have been in high demand and it has also become a very important module in embedded systems. Recent years more and more attentions have been paid on 3D graphics rendering. As we know it is very difficult to achieve real-time interactive request in the complex 3D graphics rendering on a signal CPU, therefore a dedicated graphics processor is need to enhance the rendering speed. But in embedded system, source is limited and power is supplied by battery, so that the 3D graphic processing for mobile environment can not employ the same algorithm or architecture as in the pc environment. In this paper, we review a full 3D graphics pipeline and discuss optimizations of graphics architecture have been made to overcome the shortcomings in mobile environment.

A new architecture for transport stream demultiplexer (TS Demux) in high definition television (HDTV) decoder is presented in this paper, which is able to demultiplex two TS inputs synchronously. We have pursued a hardware-based design that controlled by the software to yield high performance in the least silicon area. The key parts of the architecture, including PID filter, section filter and Memory Control Unit (MCU), are shared by the two TS inputs in terms of a time slice. Owing to the elaborate shared mechanism, our design is efficient to support more tremendous functions with less resource compared to the current scheme.