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91.
This paper proposes a probabilistic variant of the SOM-kMER (Self Organising Map-kernel-based Maximum Entropy learning Rule)
model for data classification. The classifier, known as pSOM-kMER (probabilistic SOM-kMER), is able to operate in a probabilistic
environment and to implement the principles of statistical decision theory in undertaking classification problems. A distinctive
feature of pSOM-kMER is its ability in revealing the underlying structure of data. In addition, the Receptive Field (RF) regions
generated can be used for variable kernel and non-parametric density estimation. Empirical evaluation using benchmark datasets
shows that pSOM-kMER is able to achieve good performance as compared with those from a number of machine learning systems.
The applicability of the proposed model as a useful data classifier is also demonstrated with a real-world medical data classification
problem. 相似文献
92.
This paper presents an approach to automated building grouping and generalization. Three principles of Gestalt theories, i.e.
proximity, similarity, and common directions, are employed as guidelines, and six parameters, i.e. minimum distance, area
of visible scope, area ratio, edge number ratio, smallest minimum bounding rectangle (SMBR), directional Voronoi diagram (DVD),
are selected to describe spatial patterns, distributions and relations of buildings. Based on these principles and parameters,
an approach to building grouping and generalization is developed. First, buildings are triangulated based on Delaunay triangulation
rules, by which topological adjacency relations between buildings are obtained and the six parameters are calculated and recorded.
Every two topologically adjacent buildings form a potential group. Three criteria from previous experience and Gestalt principles
are employed to tell whether a 2-building group is ‘strong,’ ‘average’ or ‘weak.’ The ‘weak’ groups are deleted from the group
array. Secondly, the retained groups with common buildings are organized to form intermediate groups according to their relations.
After this step, the intermediate groups with common buildings are aggregated or separated and the final groups are formed.
Finally, appropriate operators/algorithms are selected for each group and the generalized buildings are achieved. This approach
is fully automatic. As our experiments show, it can be used primarily in the generalization of buildings arranged in blocks.
相似文献
Robert WeibelEmail: |
93.
Jean-Charles Créput Abderrafiaâ Koukam 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2008,12(11):1125-1141
The paper presents an extension of the self- organizing map (SOM) by embedding it into an evolutionary algorithm to solve
the Vehicle Routing Problem (VRP). We call it the memetic SOM. The approach is based on the standard SOM algorithm used as
a main operator in a population based search. This operator is combined with other derived operators specifically dedicated
for greedy insertion moves, a fitness evaluation and a selection operator. The main operators have a similar structure based
on the closest point findings and local moves performed in the plane. They can be interpreted as performing parallels and
massive insertions, simulating the behavior of agents which interact continuously, having localized and limited abilities.
This self-organizing process is intended to allow adaptation to noisy data as well as to confer robustness according to demand
fluctuation. Selection is intended to guide the population based search toward useful solution compromises. We show that the
approach performs better, with respect to solution quality and/or computation time, than other neural network applications
to the VRP presented in the literature. As well, it substantially reduces the gap to classical Operations Research heuristics,
specifically on the large VRP instances with time duration constraint. 相似文献
94.
Brain impediments such as dementia are a serious problem today. It would be very useful if software for private diagnosis
were available. In this paper, we show the effectiveness of the human random generation test (HRG) for such software, and
propose a set of four indices to be used for classifying the HRG data. Human-generated random numbers have strong characteristics
compared to computer-generated random numbers, and these are known to be correlated to the individual characters of the subjects.
However, analysis using the correlation dimension or HMM requires a long data sequence, and thus is not suitable for diagnoses.
We therefore focus on short sequences of HRG and search for effective indices to detect signs of brain disability hidden in
the HRG data. We studied data from subjects of different age groups, and successfully differentiated the data from the different
groups.
This work was presented in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January
25–27, 2007 相似文献
95.
Ultrasonic sensors have been widely applied in mobile robots to obtain environmental information and avoid obstacles. In general, a typical domestic environment consists of planes, edges and corners. It is usually difficult to distinguish a plane from a corner directly with a single ultrasonic sensor. To overcome this difficulty, a corner differentiation algorithm for a single ultrasonic sensor is proposed in this paper. The algorithm is based on the features of all of the actual reflection points from the environment obtained by a reflection search algorithm from which the corners are realized by a corner differentiation algorithm. The experimental results show that the developed algorithm can successfully detect all planes and corners. Furthermore, an environmental map can be built based on the information obtained on planes and corners. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
96.
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
97.
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
98.
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: |
99.
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
100.
《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