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101.
Geler Zoltan Kurbalija Vladimir Ivanović Mirjana Radovanović Miloš 《Knowledge and Information Systems》2022,64(10):2797-2832
Knowledge and Information Systems - In the field of time series data mining, the accuracy of the simple, but very successful nearest neighbor (NN) classifier directly depends on the chosen... 相似文献
102.
Mobile Robot Trajectory Planning Under Kinematic and Dynamic Constraints for Partial and Full Field Coverage 总被引:1,自引:0,他引:1
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The constantly rising food demand of a steadily increasing world population requires improvement in efficiency, competitiveness, and productivity of current meat and dairy production systems. Thus, robotics‐based approaches have an important role to play, especially in dairy cattle farming, because the intensive grazing systems depend on numerous time‐consuming and tedious operations required to be carried out to assure an optimal cattle feeding as well as utilization of forage resources. These operations range from data acquisition considering the amount and quality of available forage within the paddocks, to carrying out maintenance operations in order to safeguard high yield with required quality and availability of the forage throughout the whole grazing season. This issue is addressed within the ICT‐AGRI project i‐LEED, in which one of the main tasks is to build accurate and feasible trajectories for a scouting and a maintenance robot to fully or partially cover the paddocks, as well as to reach only targeted spots previously located. This paper presents an original and fully operational method for trajectory planning by designing segments of clothoids while taking into account additional dynamic constraints, such as the steering rate capacity of the robot, its speed, and the maximally allowed transverse acceleration. In case of specific points to reach within a paddock, this approach is completed by morphological operations to first define regions and next rank them w.r.t. the minimal length of travel by solving the traveling salesman problem. Based on the kinematic and dynamic properties of the scouting and maintenance robots devoted to the i‐LEED project, the performances of the proposed planning approaches are presented. 相似文献
103.
The dynamics of the Cu-O chain in YBa2Cu3O7–
was investigated by emission Mössbauer spectroscopy, using57Co dopant to microprobe the Cu(1) site. The transformation of the 5-coordinate trigonal-bipyramidal cobalt configuration (species B) to a square-pyramidal one (species C) is induced by the zig-zag motion of the chain. The thermodynamical parameters associated with this conversion were determined, H
0=38±5 kJ/mol (0.4 eV) and S
0=127±20 J/K. About 40% of species C does not convert into B at all. We suggest that the inconvertible C has a static square-pyramidal configuration at twin-boundaries where the chain motion is damped. In the57Fe-doped compound, the iron atoms form linear clusters, and the Cu-O chain motion and also the B-to-C conversion is retarded in the temperature range 200–350 K. A new minor Co species similar to B (namely, B') is reported, which is presumably situated on the grain boundaries. Its nonmetallic environment is reflected in the relatively large value of isomer shift. The properties of the electric field gradient tensor at major Co(Fe) sites are also discussed. 相似文献
104.
D. Szabo Sarkadi 《Journal of the American Oil Chemists' Society》1958,35(9):472-475
Summary Fatty acid/triglyceride systems deviate from ideality, consequently the use of activities is needed when determining the vaporization
efficiency in deodorizers.
In normal laboratory deodorizers the vaporization efficiency is low and is dependent on the steam flow rate, also on the absolute
pressure.
To obtain a vaporization efficiency of unity, independent of the steam flow rate and of the absolute pressure, heating of
the head of the deodorizer is necessary in order to eliminate cooling and condensation effects.
An isothermic deodorizer has been constructed, the steaming flask of which is immersed entirely in the heating bath. No separate
vapor generator and superheater are needed; these are incorporated in the deodorizer and ensure a regular steam flow.
At very high flow rates the vaporization efficiency decreases slightly. 相似文献
105.
William M. Coleman Peggy Szabo David L. Wooton Harry C. Dorn Larry T. Taylor 《Fuel》1977,56(2):195-198
Solvent-refined coal (SRC), THF1-insoluble SRC, THF-soluble SRC and three of its ‘size-separated’ fractions have been analysed for eleven metallic elements via flameless atomic absorption spectroscopy. Prior to analysis each sample was wet ashed with equal quantities of concentrated H2SO4 and 30% H2O2. Matrix effects were compensated for by the method of standard additions and deuterium-arc background correction. Mg, Al, K and Fe were found in greatest concentration in all samples. The concentration of Pb and Cd was measurable only in THF-insoluble SRC. 相似文献
106.
Barringer JL Szabo Z Kauffman LJ Barringer TH Stackelberg PE Ivahnenko T Rajagopalan S Krabbenhoft DP 《The Science of the total environment》2005,346(1-3):169-183
Concentrations of total mercury (Hg) from 2 microg/L (the USEPA maximum contaminant level) to 72 microg/L in water from about 600 domestic wells in residential parts of eight counties in southern New Jersey have been reported by State and county agencies. The wells draw water from the areally extensive (7770 km(2)) unconfined Kirkwood-Cohansey aquifer system, in which background concentrations of Hg are about 0.01 microg/L or less. Hg is present in most aquifer materials at concentrations <50 microg/kg, but is at 100--150 microg/kg in undisturbed surficial soils. No point sources of contamination to the affected areas have been conclusively identified. To determine whether high levels of Hg in ground water are related to a particular land use and (or) water chemistry, water samples from 105 wells that tap the aquifer system were collected by the United States Geological Survey. These included randomly selected domestic wells, domestic and observation wells in selected land uses, and sets of clustered observation wells--including two sets that are downgradient from residential areas with Hg-contaminated ground water. Hg concentrations in filtered samples (Hg(f)) were at or near background levels in water from most wells, but ranged from 0.1 to 3.8 microg/L in water from nearly 20% of wells. Hg(f) concentrations from 0.0001 to 0.1 microg/L correlated significantly and positively with concentrations of other constituents associated with anthropogenic inputs (Ca, Cl, Na, and NO(3)) and with dissolved organic carbon. Hg(f) concentrations >0.1 microg/L did not correlate significantly with concentrations of the inorganic constituents. Hg(f) concentrations near or exceeding 2 microg/L were found only in water from wells in areas with residential land use, but concentrations were at background levels in most water samples from undeveloped land. The spatial distribution of Hg-contaminated ground water appears to be locally and regionally heterogeneous; no extensive plumes of Hg contamination have yet been identified. 相似文献
107.
Annica A.M. Andersson Roger Andersson Vieno Piironen Anna-Maija Lampi Laura Nyström Danuta Boros Anna Fraś Kurt Gebruers Christophe M. Courtin Jan A. Delcour Mariann Rakszegi Zoltan Bedo Jane L. Ward Peter R. Shewry Per Åman 《Food chemistry》2013,136(3-4):1243-1248
A large and diverse material collection of whole grain wheat samples (n = 129) was analysed for total dietary fibre (TDF) content and composition, including fructan (11.5–15.5%). Correlations between the dietary fibre components, associated bioactive components (e.g. tocols, sterols, phenolic acids and folates) and agronomic properties previously determined on the same samples were found with multivariate analysis (PCA). Samples from the same countries had similar characteristics. The first PC described variation in components concentrated in the starchy endosperm (e.g. starch, β-glucan and fructan) and the dietary fibre components concentrated in the bran (e.g. TDF, arabinoxylan and cellulose). The second PC described the variation in kernel weight and other bran components such as alkylresorcinols, tocols and sterols. Interestingly, there was no correlation among these different groups of bran components, which reflected their concentration in different bran tissues. The results are of importance for plant breeders who wish to develop varieties with health-promoting effects. 相似文献
108.
Zoltan Huszka Kund Molnar 《International Journal of Circuit Theory and Applications》2019,47(5):805-811
A former scaling technique made it possible to eliminate the effect of the automatically generated derivatives at bipolar non–quasi-static (NQS) modeling in Verilog-A. An alternative technique is proposed here, which makes the derivatives of selected variables zero. The method was verified on the examples of bipolar NQS variants. The confirming results open a new perspective for increasing the flexibility of Verilog-A compact modeling along with the reduction of computational efforts. 相似文献
109.
Sinia N. Dodi Stevan D. Popov Jelena M. Dodi Jovana A. Rankovi Zoltan Z. Zavargo 《Renewable & Sustainable Energy Reviews》2009,13(9):2722-2727
The Autonomous Province of Vojvodina is an Autonomous Province in Serbia, containing about 27% of its total population according to the 2002 Census. Contribution of renewable energy sources in total energy consumption of Vojvodina contemporary amounts to less than 1%, apropos 280 GWh/year. By combining of methods of introduction of new and renewable sources, systematic application of methods for increasing of energetic efficacy, as well as of introduction of the new technologies, percentage of contribution of the non-conventional energy sources in Vojvodina could be increased to as much as 20%. This paper presents the potential of development of bioethanol production in Vojvodina. Production of bioethanol on small farms can be successfully applied for processing of only 30 kg of corn per day, with obtaining of crude ethanol in the so-called “brandy ladle” and use of lygnocellulosic agricultural wastes as an energy source. In a case of construction of a larger number of such plants, the only possible solution is seen in the principle of construction of the so-called “satellite plants”, which will on small farm produce crude ethanol, with obtaining and consumption of stillage for animal feeding, and consumption of agricultural wastes as energetic fuels. If stillage is to be used as feed in wet feeding, it is estimated that, because of restrictions established by the magnitude of animal farm, the upper limit of capacity of such enterprises that process is at some 10–15 tons of corn per day, and production of 3000–3500 hL of absolute ethanol per day. In such a case, for animal feeding necessary is to have herd with 1300–1700 of milking cows or 5000–25,000 heads of sheep and/or pigs. Technological model of separate grain processing ad bioethanol production from dextrose hydrolysates of starch is interesting for countries possessing plants for bioethanol production from molasses and plants for cereals processing into starch and dextrose hydrolysates of starch. 相似文献
110.
Corbo CP Othman NA Gutkin MC Alonso Adel C Fulop ZL 《Microscopy research and technique》2012,75(3):325-333
Cellular composition of the adult zebrafish (Danio rerio) optic tectal cortex was examined in this study. Morphological techniques such as 1 μm thick serial plastic sections stained with osmium tetroxide and toluidine blue, modified rapid Golgi silver impregnation, GFAP immunohistochemistry, confocal microscopy, as well as scanning and transmission electron microscopy were used. Neuronal and glial components are described and the layers of the cortex are revisited. Specific neuronal arrangements as well as unique glial/ependymal cells are described. A three dimensional rendering of the astrocytic fiber arrangement in the marginal zone is presented and a composite drawing summarizes the cellular composition of the optic tectum. 相似文献