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691.
Grzegorz Szwoch Damian Ellwart Andrzej Czyżewski 《Journal of Real-Time Image Processing》2016,11(1):111-125
Results of evaluation of the background subtraction algorithms implemented on a supercomputer platform in a parallel manner are presented in the article. The aim of the work is to chose an algorithm, a number of threads and a task scheduling method, that together provide satisfactory accuracy and efficiency of a real-time processing of high-resolution camera images, maintaining the cost of resources usage at a reasonable level. Two selected algorithms: the Gaussian mixture models and the Codebook, are presented and their computational complexity is discussed. Various approaches to the parallel implementation, including assigning the image pixels to threads, the task scheduling methods and the thread management systems, are presented. The experiments were performed on a supercomputer cluster, using a single machine with 12 physical cores. The accuracy and performance of the implemented algorithms were evaluated for varying image resolutions and numbers of concurrent processing threads. On a basis of the evaluation results, an optimal configuration for the parallel implementation of the system for real-time video content analysis on a supercomputer platform was proposed. 相似文献
692.
Francesco Bernardini Robert Brijder Matteo Cavaliere Giuditta Franco Hendrik Jan Hoogeboom Grzegorz Rozenberg 《Natural computing》2011,10(1):17-38
We continue the formal study of multiset-based self-assembly. The process of self-assembly of graphs, where iteratively new
nodes are attached to a given graph, is guided by rules operating on nodes labelled by multisets. In this way, the multisets
and rules model connection points (such as “sticky ends”) and complementarity/affinity between connection points, respectively.
We identify three natural ways (individual, free, and collective) to attach (aggregate) new nodes to the graph, and study
the generative power of the corresponding self-assembly systems. For example, it turns out that individual aggregation can
be simulated by free or collective aggregation. However, we demonstrate that, for a fixed set of connection points, collective
aggregation is rather restrictive. We also give a number of results that are independent of the way that aggregation is performed. 相似文献
693.
Micha Marcinkowski Toma Pilys Damian Garbicz Jan Piwowarski Damian Mielecki Grzegorz Nowaczyk Micha Taube Maciej Gielnik Maciej Kozak Maria Winiewska-Szajewska Ewa Szoajska Janusz Dbski Agnieszka M. Maciejewska Kaja Przygoska Karolina Ferenc Elbieta Grzesiuk Jarosaw Poznaski 《International journal of molecular sciences》2021,22(9)
The FTO protein is involved in a wide range of physiological processes, including adipogenesis and osteogenesis. This two-domain protein belongs to the AlkB family of 2-oxoglutarate (2-OG)- and Fe(II)-dependent dioxygenases, displaying N6-methyladenosine (N6-meA) demethylase activity. The aim of the study was to characterize the relationships between the structure and activity of FTO. The effect of cofactors (Fe2+/Mn2+ and 2-OG), Ca2+ that do not bind at the catalytic site, and protein concentration on FTO properties expressed in either E. coli (ECFTO) or baculovirus (BESFTO) system were determined using biophysical methods (DSF, MST, SAXS) and biochemical techniques (size-exclusion chromatography, enzymatic assay). We found that BESFTO carries three phosphoserines (S184, S256, S260), while there were no such modifications in ECFTO. The S256D mutation mimicking the S256 phosphorylation moderately decreased FTO catalytic activity. In the presence of Ca2+, a slight stabilization of the FTO structure was observed, accompanied by a decrease in catalytic activity. Size exclusion chromatography and MST data confirmed the ability of FTO from both expression systems to form homodimers. The MST-determined dissociation constant of the FTO homodimer was consistent with their in vivo formation in human cells. Finally, a low-resolution structure of the FTO homodimer was built based on SAXS data. 相似文献
694.
O. A. Rozenberg E. A. Pashchenko A. G. Mamalis 《Journal of Materials Engineering and Performance》2012,21(6):1099-1105
Despite being one of the oldest objects of materials science, powder structures still are of great interest. Significant information can be provided by analysis of interactions between particles in powder medium. This article discusses the experimental results from measurements of dynamics of probing solvent removal from pore volume, linked to interparticle contacts. The concept of topological uniformity of pore space in powder bodies is formulated and distributions of three-dimensional interparticle contacts by volumes are analyzed. 相似文献
695.
Artur Podhorodecki Grzegorz Zatryb Lukasz W Golacki Jan Misiewicz Jacek Wojcik Peter Mascher 《Nanoscale research letters》2013,8(1):98
Silicon nanocrystals embedded in a silicon-rich silicon oxide matrix doped with Er3+ ions have been fabricated by electron cyclotron resonance plasma-enhanced chemical vapor deposition. Indirect excitation of erbium photoluminescence via silicon nanocrystals has been investigated. Temperature quenching of the photoluminescence originating from the silicon nanocrystals and the erbium ions has been observed. Activation energies of the thermally activated quenching process were estimated for different excitation wavelengths. The temperature quenching mechanism of the emission is discussed. Also, the origin of visible emission and kinetic properties of Er-related emission have been discussed in details. 相似文献
696.
Alicja Nowaczyk Magdalena Kowalska Jacek Nowaczyk Grzegorz Grzek 《International journal of molecular sciences》2021,22(11)
The year 2021 is the 100th anniversary of the confirmation of the neurotransmission phenomenon by Otto Loewi. Over the course of the hundred years, about 100 neurotransmitters belonging to many chemical groups have been discovered. In order to celebrate the 100th anniversary of the confirmation of neurotransmitters, we present an overview of the first two endogenous gaseous transmitters i.e., nitric oxide, and carbon monoxide, which are often termed as gasotransmitters. 相似文献
697.
Highly graphitic carbon nanocoils were synthesised from the catalytic graphitization of carbon spherules obtained by the hydrothemal treatment of different saccharides (sucrose, glucose and starch). This nanostructured carbon was characterized by X-ray power diffraction, N2 adsorption and microscopy techniques (SEM and TEM). The carbon nanocoils were used as a support for PtRu nanoparticles, which were well-dispersed over the carbon surface. This catalytic system was investigated for use as an electrocatalyst for methanol electrooxidation in an acid medium. The experiments were carried out at two working temperatures (25 °C and 60 °C). It was found that the carbon nanocoils supporting PtRu nanoparticles exhibit a high catalytic activity, which is even higher than that of conventional carbon supports (Vulcan XC-72R). We believe that the high electrocatalytic activity of the carbon nanocoils presented here is due to the combination of a good electrical conductivity, derived from their graphitic structure, and a wide porosity that allows the diffusional resistances of reactants/products to be minimized. 相似文献
698.
699.
Martin Peter Elsner Grzegorz Ziomek Andreas Seidel‐Morgenstern 《American Institute of Chemical Engineers》2009,55(3):640-649
The focus of this work is to study the enantioseparation of conglomerate forming systems using an innovative configuration for preferential crystallization. Two batch crystallizers are coupled by an exchange of their liquid phases. In each vessel one of the two enantiomers is seeded initially and crystallizes subsequently. Compared with conventional single batch crystallization the exchange of the crystal free liquid phases between two crystallizers leads to an increase of the concentrations of the preferred enantiomers and therefore to an increase of the driving forces for the crystallization. This enhances the productivity of the process compared with the conventional operation. © 2009 American Institute of Chemical Engineers AIChE J, 2009 相似文献
700.
A. V. Agranovskii G. N. Korol'kov A. V. Rozenberg V. A. Sborshchikov 《Measurement Techniques》1999,42(11):1075-1079
The underwater sound field in the vicinity of interference maxima can be approximated locally by a quasi-plane wave. The sensitivity
measurement technique discussed in the article calls for measurements to be performed at times when the calibrated and the
standard hydrophones reside in the zone of an interference maximum of the sound field generated by a moving radiator. The
motion of the latter can be utilized to formulate a simple dynamic algorithm for monitoring the entry of acoustic transducers
into the zone of a maximum of the sound field.
Translated from Izmeritel'naya Tekhnika, No. 11, pp. 49–52, November, 1999. 相似文献