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61.
Results of calculations based on a linearized multicomponent mass transfer theory developed by Burghardt and Krupiczka are compared with experimental data of Modine for condensation-evaporation process in ternary systems. These data have been obtained for acetone-benzene-nitrogen and acetone-benzene-helium in a welted wall column. Models I and II, which take into account diffusional interactions of components in a mullicomponent mixture show good agreement with the experiments as well as with other calculation methods (Krishna-Standart and Toor-Stewart-Prober). When multicomponent mass transfer occurs in the presence of inert species, a straightforward Model II is recommended. Model I, which is more universal, requires some iterative calculations with respect to the sum of mass fluxes. According to theoretical considerations the latter model is limited to the case of low total mass flux. The results of calculations for the systems studied were reasonably good though the total mass fluxes were not small. The calculation procedure based on the presented linearized models are convergent to the proper solutions in contrast to the Krishna-Standart Model IV which in some cases can be unstable. 相似文献
62.
Jan Quadflieg Mike Preuss Günter Rudolph 《Genetic Programming and Evolvable Machines》2014,15(4):433-476
We present the evolution and current state of the Mr. Racer car racing controller that excelled at the corresponding TORCS competitions of the last years. Although several heuristics and black-box optimization methods are employed, the basic idea of the controller architecture has been to take over many of the mechanisms human racing drivers apply. They learn the track geometry, plan ahead, and wherever necessary, adapt their plans to the current circumstances quickly. Mr. Racer consists of several modules that have partly been adapted and optimized separately, where the final tuning is usually done with respect to a certain racing track during the warmup phase of the TORCS competitions. We also undertake an experimental evaluation that investigates how the controller profits from adding some of the modules to a basic configuration and which modules are most important for reaching the best possible performance. 相似文献
63.
Daniel?ZemanEmail author Ond?ej?Du?ek David?Mare?ek Martin?Popel Loganathan?Ramasamy Jan??těpánek Zdeněk??abokrtsky Jan?Haji? 《Language Resources and Evaluation》2014,48(4):601-637
We present HamleDT—a HArmonized Multi-LanguagE Dependency Treebank. HamleDT is a compilation of existing dependency treebanks (or dependency conversions of other treebanks), transformed so that they all conform to the same annotation style. In the present article, we provide a thorough investigation and discussion of a number of phenomena that are comparable across languages, though their annotation in treebanks often differs. We claim that transformation procedures can be designed to automatically identify most such phenomena and convert them to a unified annotation style. This unification is beneficial both to comparative corpus linguistics and to machine learning of syntactic parsing. 相似文献
64.
Bohdan Schneider Jan Štokr Pavel Schmidt Marian Mihailov Stoil Dirlikov Nadezhda Peeva 《Polymer》1979,20(6):705-712
Infrared and Raman spectra of atactic PMMA and infrared spectra of stereoregular PMMA and of its four deuterated derivatives , were measured. They were used to assign the bands of stretching and deformation vibrations of CH2, CCH3 and OCH3 groups in the infrared and Raman spectra and to discuss the effect of stereoregularity on these bands in the infrared spectra. 相似文献
65.
With the help of DTA, DTG elementary analysis of carbonized residues and ESR spectroscopy the influence of anionic form on thermooxidation of trimethylammoniumhydroxyprophyl (TMAHP)–cellulose was studied. At 300°C the percentage of carbon in carbonized residue thermolyzed in oxidative atmosphere is higher than for the sample degraded in inert atmosphere. The percentage of hydrogen decreases simultaneously. The concentration of free radicals in thermolyzed residue also increases due to the presence of oxygen. We propose that oxygen is abstracting the hydrogen atoms from polysaccharide and unpaired electrons on carbon atoms are produced. At 400°C the percentage of carbon in residues prepared at inert atmosphere is higher than for residue formed at oxidative atmosphere. Also the concentration of free radicals in thermolyzed residues obtained in inert atmosphere is greater than for those from oxidative ones. That is why suppose that at this temperature oxygen is bonded to polysaccharide residue and free radicals are terminated. From the semiquantitative DTA we can make the following sequence of samples according to their increasing thermooxidative effect: unmodified cellulose < A–HSO < A–Br? < A–I? < A–NO < A–H2PO < A–CH3COO? < A–HCO < A–F? < A–Cl?1 < A–OHp?. 相似文献
66.
Radim Belohlavek Dhouha Grissa Sylvie Guillaume Engelbert Mephu Nguifo Jan Outrata 《Annals of Mathematics and Artificial Intelligence》2014,70(1-2):151-184
Measures of interestingness play a crucial role in association rule mining. An important methodological problem, on which several papers appeared in the literature, is to provide a reasonable classification of the measures. In this paper, we explore Boolean factor analysis, which uses formal concepts corresponding to classes of measures as factors, for the purpose of clustering of the measures. Unlike the existing studies, our method reveals overlapping clusters of interestingness measures. We argue that the overlap between clusters is a desired feature of natural groupings of measures and that because formal concepts are used as factors in Boolean factor analysis, the resulting clusters have a clear meaning and are easy to interpret. We conduct three case studies on clustering of measures, provide interpretations of the resulting clusters and compare the results to those of the previous approaches reported in the literature. 相似文献
67.
In this paper, we present an invariant‐set‐based method for actuator and sensor fault detection and isolation in Lure systems. The Lure plant is controlled by an observer‐based feedback tracking controller, designed for the nominal (fault‐free) system. Suitable residual signals are constructed from measurable system outputs and estimates associated with the nominal observer. Faults are diagnosed by online contrasting the residual signal trajectories against sets of values that the residuals are shown to attain under healthy or faulty operation. These values are obtained via set‐invariance analysis of the system closed‐loop trajectories. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
68.
The crystal structure and molecular conformation of 2-cyano-4-bromo-4′-N,N-diethylaminoazobenzene (C17H17N4Br, mol. wt. = 357·2 a.m.u) has been determined from X-ray diffraction data; triclinic, P (No. 2), a = 10·132(11) Å, b = 12·216(16) Å, c = 6·966(11) Å, α = 104·21(9)°, β = 92·67(12)°, γ = 97·22(7)°, V = 826·5(9) Å3, Z = 2, Dc = 1·436 g cm?3, F(000) = 378, λ(MoKα) = 0·71069 Å, μ(MoKα) = 26·0 cm?1. The structure was solved by the multiple solution direct method and refined by full-matrix least-squares to R = 0·059 for 1538 independent observed reflections. The azobenzene skeleton is planar to within 0·06 Å. Most significant bonding data are: NN, 1·290(8) Å; BrC, 1·866(6) Å; mean CN (azo) 1·380(8) Å; NNC, 113·6(4) and 115·3(4)°; NCC (cis relative to NN) 125·9(4)° and 126·7(4)°; NCC (trans) 116·8°(5)° and 116·1(4)°. 相似文献
69.
One of today's grand societal challenges is to replace the current ‘take‐make‐waste’ economic model with a circular economic model that allows a gradual decoupling of economic activities from the consumption of finite virgin resources. While circular economy (CE) scholars have long lauded digital technologies such as sensors, distributed ledgers, or platforms as key enablers, our own community has not fully explored the potentials of information systems (IS) for a CE. Considering recent technological advances in software and hardware and our history of helping address wicked challenges, we believe the time is ripe to mobilise IS scholarship for a CE. Our findings from an interdisciplinary literature review show that research has primarily examined IS potentials for increasing efficiency of isolated intra‐organisational processes while neglecting the larger sustainability potential of IS to establish circular material flows—that is, slow down and close material loops across entire product lifecycles. In response, we propose directions for IS research that develop our knowledge of how IS can help understand and enact circular material flows to intensify and extend use of products and components and recycle waste materials. Our directions offer pathways to building and evaluating the problem‐solution pairing that could characterise a prolific CE‐IS relationship. 相似文献
70.
Hiroaki Tsuchiya Jan M. Macak Andrei Ghicov Luciano Taveira Patrik Schmuki 《Corrosion Science》2005,47(12):3324-3335
The present work investigates the electrochemical formation of self-organized high aspect ratio TiO2 and ZrO2 nanotube layers. The formation and growth of a self-organized porous layer can be achieved directly by anodization without any templates in fluoride containing electrolytes. The morphology of the porous layers is affected by the electrochemical conditions such as the electrolyte composition, the pH and the exact polarization treatment (such as the potential sweep rate from the open-circuit potential to the anodizing potential). For Ti, nanotube layers are formed with diameters varying from approx. 20 nm to 100 nm and lengths from approx. 0.25 μm to 2.5 μm depending on the electrolytes and pH. On the other hand, for Zr, tubes of 50 nm in diameter and up to approx. 17 μm in length can be grown—a key parameter in this case is the potential sweep rate. The large difference between Ti and Zr in the achievable thickness of nanotube layers indicates a difference in the growth mechanism which may be based on the different chemical dissolution rates of electrochemically formed oxides. 相似文献