The wireless channel has characteristics of multipath fading effect and time-varying in the mobile communication. Among them the multi-path fading effect is quite large for the performance of the system. Because th...
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The wireless channel has characteristics of multipath fading effect and time-varying in the mobile communication. Among them the multi-path fading effect is quite large for the performance of the system. Because the transmission environment is very complex, we use digital signal process to analyze propagation characteristic in wireless channel through MATLAB. This paper is mainly discussed several typical fading which are simulated using frequency transform methods through the computer. The performance of the multi-path fading channel in the mobile communication is studied by comparing BER, constellation map and eye-diagram. According to the different power of the multi-path signals, the simulations of different fading types and depths have been conducted.
Based on user interests, the personalized service has become a popular research in academic and commercial *** paper analyzes the user interests in the domestic and foreign research *** come up with a way to obtai...
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Based on user interests, the personalized service has become a popular research in academic and commercial *** paper analyzes the user interests in the domestic and foreign research *** come up with a way to obtain the User Interests data in Web log mining. What's more, in order to solve the dynamic updating user interests. This paper proposes a new quantitative model of user interests.
For the solution of insufficient test data and single information can not represent all the fault state in the analog circuit fault diagnosis, a fault diagnosis model and .a fusion algorithm based on data fusion techn...
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For the solution of insufficient test data and single information can not represent all the fault state in the analog circuit fault diagnosis, a fault diagnosis model and .a fusion algorithm based on data fusion technology is formed. The fault diagnosis information is fused with two layers: For the feature layer, the voltage and current of testing nodes are processed by different neural network in order to acquire BPA ofvarious faults. For the decision layer, ultimate result is acquired by D-S evidence theory. The results of simulation show that: Comparing with the result from the network as single fusion layer, this method has a smaller error and higher diagnosis reliability.
To solve the synchronization problems in the parallel programming, such as dead lock, priority inversion and convoy, the concept of transactional memory(TM) had been introduced. In this paper, some basic concepts ...
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To solve the synchronization problems in the parallel programming, such as dead lock, priority inversion and convoy, the concept of transactional memory(TM) had been introduced. In this paper, some basic concepts about TM are presented at first, and several key implementation technologies arc analyzed. Then some typical TM systems are introduced in detail. Finally, the examples using OpenTM or Intel C++ STM Compiler Prototype Edition which are the extensions of OpenMP are given.
this paper describes in detail construction of The Grid Parallel Computing of books and documents, system solves the problems and methods, as well as design to realization of MDS module. Scientific data grid softw...
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this paper describes in detail construction of The Grid Parallel Computing of books and documents, system solves the problems and methods, as well as design to realization of MDS module. Scientific data grid software adopt SOA, through the standardization of metadata and metadata-based resource discovery to make users can be achieved uniform access to distributed heterogeneous data resources in two phases of query.
This paper proposes online video feature label extraction method during the time when they were retrieved from the Internet This method is used in an online video retrieving system to extract feature labels of a v...
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This paper proposes online video feature label extraction method during the time when they were retrieved from the Internet This method is used in an online video retrieving system to extract feature labels of a video clip automatically. By collecting attributes of videos, basic features are produced, and then capture the key frames of video. Create label templates, analyze and extract other features by matching the image analysis result in the template library to decide the feature labels of the online video clips.
Atmospheric turbulence produces fluctuations in the irradiance of the transmitted optical beam, which is known as atmospheric scintillation, severely degrading the link performance. Turbo product codes (TPC) has a...
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Atmospheric turbulence produces fluctuations in the irradiance of the transmitted optical beam, which is known as atmospheric scintillation, severely degrading the link performance. Turbo product codes (TPC) has attracted much attention for its high coding rate and strong abilities of defeating long burst errors, which is a good choice for the highly correlated optical channel. In this paper, a scheme combining turbo product codes (TPC) and pulseposition modulation (PPM) has been analyzed for the temporally correlated satellite-to-ground optical channel with an avalanche photodiode (APD) receiver and Gaussian ther- mal noise. The results indicate that TPC is capable of defeating long burst errors and it can offer enough temporally diversity for the free-space optical communication (FSOC) system.
As the fault modes of mixed-signal circuits growing, aiming at the features for its signal are both analog and digital amount, the paper analyzed that the fault diagnosis program of mixed-signal circuits with gene...
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As the fault modes of mixed-signal circuits growing, aiming at the features for its signal are both analog and digital amount, the paper analyzed that the fault diagnosis program of mixed-signal circuits with genetic algorithms by using SABER simulation method to inject faults and data collection based on a brief discussion of basic principles and operation of genetic algorithms, focused on consideration for the fitness functions of genetic algorithms, and then selected an optimization genetic algorithm to a specific airborne DC converter circuit's fault diagnosis, verifying the effectiveness of the method, provided a new diagnostic method for mixed-signal circuits.
An optimal bit rate allocation algorithm for image compressed with SPIHT is proposed. A threshold-based transmission scheme of SPIHT bit streams and a rate optimization algorithm based on threshold after analyzing...
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An optimal bit rate allocation algorithm for image compressed with SPIHT is proposed. A threshold-based transmission scheme of SPIHT bit streams and a rate optimization algorithm based on threshold after analyzing the characteristics of SPIHT bit stream are developed in this paper. Simulation results show that, the proposed technical solution is better than the traditional bit stream allocation schemes in terms of the packet number used to decode and PSNR of reconstructed image. Therefore, the scheme is more potential and practical for future efficient and reliable wireless multimedia communication systems.
Particle system has long been a topic of research and has many applications. However, due to its complexity, the fast collision detection between particles and scene geometry is still a bottleneck for real-time or...
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Particle system has long been a topic of research and has many applications. However, due to its complexity, the fast collision detection between particles and scene geometry is still a bottleneck for real-time or interactive applications. As a fuzzy system, visually correct is more important than physical accuracy at most time for particle system. In this paper, considering its simplicity, we propose to use a simplified version, which can be generated by any simplification method, to approximate the boundary of original scene mesh. We proposed a GOctree acceleration structure to subdivide the scene space, combining the advantages of both the uniform grid and octree. The resultant G-Octree based agent is uploaded onto GPU to implement a parallel particle system. An encoding scheme is introduced to pack the hierarchical G-Octree structure into a flat 2D texture to exploit the optimized performance of texture memory system on GPU context Compared with existing methods, the proposed method has potential to handle complex scene in practical applications. The experiments verify its effectiveness.
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