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81.
82.
Marek Franaszek Geraldine S. Cheok Christoph Witzgall 《Automation in Construction》2009,18(3):265-274
The use of 3D imaging systems (e.g., laser scanners) in construction has grown significantly in the past decade. Range images acquired with such systems often require registration. This paper describes an automatic method to rapidly locate spheres and perform a registration based on three pairs of matching points (centers of fitted spheres) in two range images. The proposed method is directly applicable for regularly gridded datasets obtained with instruments that are typically used for construction applications and whose maximum ranges are greater than 50 m. A lab was scanned from two locations at three different scan densities. Four spheres were located in the lab, and the total number of points hitting the four spheres was a small fraction (< 0.01%) of all the points in the dataset. At the highest scan density, the registration of two datasets with 6.4 × 106 and 3.4 × 106 points is obtained in less than 30 s. At the medium scan density, two range images with 1.6 × 106 and 0.8 × 106 points can be registered in less than 2 s. 相似文献
83.
Colony-blot assay with anti-p60 antibodies as a method for quick identification of Listeria in food 总被引:2,自引:0,他引:2
Wieckowska-Szakiel M Bubert A Rózalski M Krajewska U Rudnicka W Rózalska B 《International journal of food microbiology》2002,72(1-2):63-71
The present study evaluated the ability to isolate Listeria from foods, using shortened procedure of sample enrichment followed by immunomagnetic separation or filtration methods, and serological identification of isolated bacteria by colony-blot and Western blot methods with anti-p60 antibodies. By these rapid methods, identification of Listeria was achieved in much shorter time (40-48 h) than with standard cultivation and biochemical identification procedures. The rapid methods used are easy to perform and, what is most important, their specificity is very high and fulfills the expectations. The possibility to select Listeria colonies growing on non-selective media by blotting with anti-p60 antiserum seems to be particularly valuable in examination of food samples containing/not too many Listeria (1-10 CFU/25 g). However, the blot method using anti-PepD mAb specific to unique region of L. monocytogenes p60 is necessary to distinguish L. monocytogenes from other Listeria species. 相似文献
84.
Marek Petrik Shlomo Zilberstein 《Annals of Mathematics and Artificial Intelligence》2006,48(1-2):85-106
A wide range of combinatorial optimization algorithms have been developed for complex reasoning tasks. Frequently, no single
algorithm outperforms all the others. This has raised interest in leveraging the performance of a collection of algorithms
to improve performance. We show how to accomplish this using a Parallel Portfolio of Algorithms (PPA). A PPA is a collection
of diverse algorithms for solving a single problem, all running concurrently on a single processor until a solution is produced.
The performance of the portfolio may be controlled by assigning different shares of processor time to each algorithm. We present
an effective method for finding a PPA in which the share of processor time allocated to each algorithm is fixed. Finding the
optimal static schedule is shown to be an NP-complete problem for a general class of utility functions. We present bounds
on the performance of the PPA over random instances and evaluate the performance empirically on a collection of 23 state-of-the-art
SAT algorithms. The results show significant performance gains over the fastest individual algorithm in the collection.
相似文献
85.
Marek Karpinski Ion I. Mandoiu Alexander Olshevsky Alexander Zelikovsky 《Algorithmica》2005,42(2):109-120
The Quality of Service Multicast Tree Problem is a generalization of
the Steiner tree problem which appears in the context of multimedia
multicast and network design. In this generalization, each node
possesses a rate and the cost of an edge with length l in a
Steiner tree T connecting the source to non-zero rate nodes is l
· re, where re is the maximum node rate in the component of
T-{e} that does not contain the source. The best previously
known approximation ratios for this problem (based on the best known
approximation factor of 1.549 for the Steiner tree problem in
networks) are 2.066 for the case of two non-zero rates and 4.212 for
the case of an unbounded number of rates. In this paper we give
improved approximation algorithms with ratios of 1.960 and 3.802,
respectively. When the minimum spanning tree heuristic is used for
finding approximate Steiner trees, then the previously best known
approximation ratios of 2.667 for two non-zero rates and 5.542 for an
unbounded number of rates are reduced to 2.414 and 4.311,
respectively. 相似文献
86.
Pitch detection methods are widely used for extracting musical data from digital signals. A review of those methods is presented in the paper. Since musical signals may contain noise and distortion, detection results can be erroneous. In this paper a new method employing music prediction to support pitch determination is introduced. This method was developed in order to override disadvantages of standard pitch detection algorithms. The new approach utilizes signal segmentation and pitch prediction based on musical knowledge extraction employing artificial neural networks. Signal segmentation allows for estimating the pitch for a single note as a whole, therefore suppressing errors in transient and decay phases. Pitch prediction helps correcting pitch estimation errors by tracking musical context of the analyzed signal. As it was shown in the experimental results, pitch estimation errors may be reduced by using both signal segmentation and music prediction techniques. 相似文献
87.
We address several problems concerning the geometry of the space of Hermitian operators on a finite-dimensional Hilbert space, in particular the geometry of the space of density states and canonical group actions on it. For quantum composite systems we discuss and give examples of entanglement measures. 相似文献
88.
A convenient synthetic procedure for preparing nickel carboxylated phthalocyanine is reported. Upon further hydroxylation, such metal phthalocyanine moieties are incorporated into several melamine-based polyester high-solids systems and the structure—property correlations are examined. Molecular level spectroscopic FTIR analysis and mechanical testing are correlated in an effort to establish structure—property relations in these coatings. It is found that the presence of metal phthalocyanine macrocycle as a cross-linking agent enhances such properties as adhesion, hardness, and impact resistance. © 1993 John Wiley & Sons, Inc. 相似文献
89.
Marek Berezowski Krzysztof Warmuziski 《Chemical Engineering and Processing: Process Intensification》1993,32(6):345-347
A method is proposed for increasing the dedusting efficiency of cyclones. The method, which is based on the introduction of the gas undergoing purification into a recycle loop, is of considerable practical importance as it enables the process to be controlled so as to maintain a constant efficiency of dust removal. 相似文献
90.
The temperature behaviour of both cadmium and nickel oxide electrodes of the sintered type (as used in sealed NiCd cells) has been investigated 相似文献