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101.
This note considers the solution to the generalized Sylvester matrix equation AV + BW = VF with F being an arbitrary matrix, where V and W are the matrices to be determined. With the help of the Kronecker map, an explicit parametric solution to this matrix equation is established. The proposed solution possesses a very simple and neat form, and allows the matrix F to be undetermined. 相似文献
102.
An accurate and compact map is essential to an autonomous mobile robot system. A topological map, one of the most popular
map types, can be used to represent the environment in terms of discrete nodes with edges connecting them. It is usually constructed
by Voronoi-like graphs, but in this paper the topological map is incrementally built based on the local grid map by using
a thinning algorithm. This algorithm, when combined with the application of the C-obstacle, can easily extract only the meaningful
topological information in real-time and is robust to environment change, because this map is extracted from a local grid
map generated based on the Bayesian update formula. In this paper, position probability is defined to evaluate the quantitative
reliability of the end node extracted by the thinning process. Since the thinning process builds only local topological maps,
a global topological map should be constructed by merging local topological maps according to nodes with high position probability.
For real and complex environments, experiments showed that the proposed map building method based on the thinning process
can accurately build a local topological map in real-time, with which an accurate global topological map can be incrementally
constructed. 相似文献
103.
Saliency, Scale and Image Description 总被引:6,自引:0,他引:6
104.
Agustin Ramirez-Agundis Rafael Gadea-Girones Ricardo Colom-Palero Javier Diaz-Carmona 《Journal of Real-Time Image Processing》2007,2(4):271-280
This paper presents a scheme and its Field Programmable Gate Array (FPGA) implementation for a system based on combining the
bi-dimensional discrete wavelet transformation (2D-DWT) and vector quantization (VQ) for image compression. The 2D-DWT works
in a non-separable fashion using a parallel filter structure with distributed control to compute two resolution levels. The
wavelet coefficients of the higher frequency sub-bands are vector quantized using multi-resolution codebook and those of the
lower frequency sub-band at level two are scalar quantized and entropy encoded. VQ is carried out by self organizing feature
map (SOFM) neural nets working at the recall phase. Codebooks are quickly generated off-line using the same nets functioning
at the training phase. The complete system, including the 2D-DWT, the multi-resolution codebook VQ, and the statistical encoder,
was implemented on a Xilinx Virtex 4 FPGA and is capable of performing real-time compression for digital video when dealing
with grayscale 512 × 512 pixels images. It offers high compression quality (PSNR values around 35 dB) and acceptable compression
rate values (0.62 bpp).
相似文献
Javier Diaz-CarmonaEmail: |
105.
Ebenezer Danso-Amoako Miklas ScholzNickolas Kalimeris Qinli YangJunming Shao 《Computers, Environment and Urban Systems》2012
This study aims to provide a rapid screening tool for assessment of sustainable flood retention basins (SFRBs) to predict corresponding dam failure risks. A rapid expert-based assessment method for dam failure of SFRB supported by an artificial neural network (ANN) model has been presented. Flood storage was assessed for 110 SFRB and the corresponding Dam Failure Risk was evaluated for all dams across the wider Greater Manchester study area. The results show that Dam Failure Risk can be estimated by using the variables Dam Height, Dam Length, Maximum Flood Water Volume, Flood Water Surface Area, Mean Annual Rainfall (based on Met Office data), Altitude, Catchment Size, Urban Catchment Proportion, Forest Catchment Proportion and Managed Maximum Flood Water Volume. A cross-validation R2 value of 0.70 for the ANN model signifies that the tool is likely to predict variables well for new data sets. Traditionally, dams are considered safe because they have been built according to high technical standards. However, many dams that were constructed decades ago do not meet the current state-of-the-art dam design guidelines. Spatial distribution maps show that dam failure risks of SFRB located near cities are higher than those situated in rural locations. The proposed tool could be used as an early warning system in times of heavy rainfall. 相似文献
106.
《国际计算机数学杂志》2012,89(6):1228-1232
In 2003, Balibrea et al. stated the problem of finding a skew-product map G on 𝕀3 holding ω G ={0}×𝕀2=ω G (x, y, z) for any (x, y, z)∈𝕀3, x≠0. We present a method for constructing skew-product maps F on 𝕀 n+1 holding ω F ={0}×𝕀 n =ω F (x 1, x 2, …, x n+1), (x 1, x 2, …, x n+1)∈𝕀 n+1, x 1≠0. 相似文献
107.
王琳 《青岛科技大学学报(自然科学版)》2012,(2):213-217
主要研究了三角代数上的Jordan三重初等映射的可加性,给出了一个保证Jor-dan三重初等映射满足可加性的充分条件。 相似文献
108.
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