150 research outputs found
Discovering Hierarchical Process Models: an Approach Based on Events Clustering
Process mining is a field of computer science that deals with discovery and
analysis of process models based on automatically generated event logs.
Currently, many companies use this technology for optimization and improving
their processes. However, a discovered process model may be too detailed,
sophisticated and difficult for experts to understand. In this paper, we
consider the problem of discovering a hierarchical business process model from
a low-level event log, i.e., the problem of automatic synthesis of more
readable and understandable process models based on information stored in event
logs of information systems.
Discovery of better structured and more readable process models is
intensively studied in the frame of process mining research from different
perspectives. In this paper, we present an algorithm for discovering
hierarchical process models represented as two-level workflow nets. The
algorithm is based on predefined event ilustering so that the cluster defines a
sub-process corresponding to a high-level transition at the top level of the
net. Unlike existing solutions, our algorithm does not impose restrictions on
the process control flow and allows for concurrency and iteration
Diaquabis(propane-1,3-diamine)copper(II) bis[diamminetetrakis(thiocyanato-κN)chromate(III)] dimethyl sulfoxide octasolvate
The ionic title complex, [Cu(C3H10N2)2(H2O)2][Cr(NCS)4(NH3)2]·8C2H6OS, consists of complex [Cu(dipr)2(H2O)2]2+ copper cations (dipr is propane-1,3-diamine), complex [Cr(NCS)4(NH3)2]− anions and uncoordinated solvent dimethyl sulfoxide (DMSO) molecules. All the metal atoms lie on crystallographic centers of symmetry. The cations are connected to the anions through N—H⋯O hydrogen bonds between the NH3 molecules of the anion and the water molecules of the cation. The DMSO molecules are involved in hydrogen-bonded linkage of the [Cr(NCS)4(NH3)2]− anions into supramolecular chains through bridging O atoms. A network of hydrogen bonds as well as short S⋯S contacts [3.5159 (12) and 3.4880 (12) Å] between the NCS groups of the complex anions link the molecules into a three-dimensional supramolecular network
Substitutional landscape of a split fluorescent protein fragment using high-density peptide microarrays
Split fluorescent proteins have wide applicability as biosensors for protein-protein interactions, genetically encoded tags for protein detection and localization, as well as fusion partners in super-resolution microscopy. We have here established and validated a novel platform for functional analysis of leave-one-out split fluorescent proteins (LOO-FPs) in high throughput and with rapid turnover. We have screened more than 12,000 variants of the beta-strand split fragment using high-density peptide microarrays for binding and functional complementation in Green Fluorescent Protein. We studied the effect of peptide length and the effect of different linkers to the solid support. We further mapped the effect of all possible amino acid substitutions on each position as well as in the context of some single and double amino acid substitutions. As all peptides were tested in 12 duplicates, the analysis rests on a firm statistical basis allowing for confirmation of the robustness and precision of the method. Based on experiments in solution, we conclude that under the given conditions, the signal intensity on the peptide microarray faithfully reflects the binding affinity between the split fragments. With this, we are able to identify a peptide with 9-fold higher affinity than the starting peptide
Effect of high-intensity ultrasonic field on fog droplet coagulation efficiency
The relevance. The urgent need to deal with fog for preventing limited visibility and creating improved meteorological conditions. Exposure to gas dispersed systems by mechanical vibrations of the ultrasonic frequency can be considered as the most effective way to deal with fog formation. However, the acoustic method has not found an industrial application for fog destruction mainly due to the lack of effective sources of acoustic exposure. Therefore, it is necessary to create emitters of higher power that provide a significantly greater range of radiation with a sound pressure level of at least 140 dB and study of their functionality. The main aim. Determination of the effectiveness of fog destruction through the use of ultrasonic vibrations generated by the developed ultrasonic emitters; identification of the most promising design of ultrasonic equipment that ensures effective destruction of fogs in open areas. Objects. Combining fog droplets under high-intensity ultrasonic exposure using specially designed ultrasonic emitters for gas media of four types. Methods. Experimental method for studying fog droplets combination under the influence of ultrasonic vibrations and their gravitational deposition. To determine the aerosol (water content and disperse composition) characteristics, during experimental studies, the authors have used the TIPAS-1 meter based on the method of small-angle scattering and the method of spectral transparency. Results. The authors established and shown the effectiveness of ultrasonic effect on fogs, as well as the possibility of its use for fog destruction in an open area. All developed disc ultrasonic emitters are capable of forming a sound pressure level within 140... 145 dB at 22±2.0 kHz. The time of fog natural destruction in the aerosol chamber is reduced by up to 11.5 times. The results obtained demonstrate that it is necessary to use more powerful disc emitters, since they can significantly reduce the time of fog destruction and increase the volumes voiced at the same time. The minimum time for establishing the required metrological range of visibility is provided by means of a directional emitter with a stepped-variable surface, forming a flat wave
Young stars and brown dwarfs surrounding Alnilam (eps Ori) and Mintaka (del Ori)
Aims: We look for new regions for the search of substellar objects. Methods:
Two circular areas, 45 arcmin-radius each, centred on the young massive star
systems Alnilam and Mintaka in the Orion Belt, have been explored. The regions
are very young (less than 10 Ma), have low extinction, and are neighbours to
sigma Orionis (~3 Ma), a young open cluster very rich in brown dwarfs and
planetary-mass objects. We have used Virtual Observatory tools, the
astro-photometric Tycho-2, DENIS and 2MASS catalogues, 10 control fields at
similar galactic latitudes, and X-ray, mid-infrared and spectroscopic data from
the literature. Results: We have compiled exhaustive lists of known young stars
and new candidate members in the Ori OB1b association, and of fore- and
background sources. A total of 136 stars display features of extreme youth,
like early spectral types, lithium in absorption, or mid-infrared flux excess.
Other two young brown dwarf and 289 star candidates have been identified from
an optical/near-infrared colour-magnitude diagram. We list additional 74 known
objects that might belong to the association. This catalogue can serve as an
input for characterisation of the stellar and high-mass substellar populations
in the Orion Belt. Finally, we have investigated the surface densities and
radial distributions of young objects surrounding Alnilam and Mintaka, and
compared them with those in the sigma Orionis cluster. We report a new open
cluster centred on Mintaka. Conclusions: Both regions can be analogs to the
sigma Orionis cluster, but more massive, more extended, slightly older, and
less radially concentrated.Comment: Accepted for publication in A&A. It will be published on line in
Sect. 14 (Catalogs and data). Tables in Appendix A will soon be available at
the CD
Comparative analysis of using natural and radiogenic lead as heat-transfer agent in fast reactors
Fast reactors with lead coolant have several advantages over analogues. Performance can be further improved by replacement of natural composition lead with radiogenic one. Thus, two main issues need to be addressed: induced radioactivity in coolant and efficient neutron multiplication factor in the core will be changed and need to be estimated. To address these issues analysis of the scheme of the nuclear transformations in the lead heat-transfer agent in the process of radiation was carried out. Induced radioactivity of radiogenic and natural lead has been studied. It is shown that replacement of lead affects multiplication factor in a certain way. Application of radiogenic lead can significantly affect reactor operation
XIV INTERNATIONAL CONFERENCE AND SEMINAR OF YOUNG SPECIALISTS ON MICRO / NANO- TECHNOLOGIES AND ELECTRON DEVICES EDM 2013 The Control of The Ultrasonic Coagulation of Dis- persed Nanoscale Particles
Abstract -In the article the results of the researches on efficiency definition of ultrasonic coagulation of ready nanodispersed product are presente. Developed measuring bench allowed to control changes of concentration of nanoparticles due to their agglomeration at the application of high-intensity ultrasonic vibrations
Substitutional landscape of a split fluorescent protein fragment using high-density peptide microarrays.
Split fluorescent proteins have wide applicability as biosensors for protein-protein interactions, genetically encoded tags for protein detection and localization, as well as fusion partners in super-resolution microscopy. We have here established and validated a novel platform for functional analysis of leave-one-out split fluorescent proteins (LOO-FPs) in high throughput and with rapid turnover. We have screened more than 12,000 variants of the beta-strand split fragment using high-density peptide microarrays for binding and functional complementation in Green Fluorescent Protein. We studied the effect of peptide length and the effect of different linkers to the solid support. We further mapped the effect of all possible amino acid substitutions on each position as well as in the context of some single and double amino acid substitutions. As all peptides were tested in 12 duplicates, the analysis rests on a firm statistical basis allowing for confirmation of the robustness and precision of the method. Based on experiments in solution, we conclude that under the given conditions, the signal intensity on the peptide microarray faithfully reflects the binding affinity between the split fragments. With this, we are able to identify a peptide with 9-fold higher affinity than the starting peptide
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