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991.
Analysis of symptom lifetime histories (trends) is widely employed in diagnostics of machines, in particular those designed for long service life. These trends, however, often reveal considerable irregularities, or fluctuations, which cannot be attributed to technical condition evolution. They can render diagnostic reasoning vague and uncertain. This results from the fact that symptom values are influenced not only by object condition parameters, but also by a number of other factors, which sometimes are dominant. More detailed analysis leads to a conclusion that a measure of symptom value fluctuations can itself be used as a diagnostic symptom. This conclusion is supported by the model-based consideration, employing a modification of the Energy Processor (EP) model, developed specifically for this purpose. To illustrate this special feature, several examples are presented and discussed, employing databases obtained for large steam turbines. 相似文献
992.
Organofluorine Isoselenocyanate Analogues of Sulforaphane: Synthesis and Anticancer Activity 下载免费PDF全文
Tomasz Cierpiał Dr. Małgorzata Kwiatkowska Prof. Dr. Piotr Kiełbasiński Lidia Mielczarek Dr. Katarzyna Wiktorska Prof. Dr. Zdzisław Chilmonczyk Małgorzata Milczarek Katarzyna Karwowska 《ChemMedChem》2016,11(21):2398-2409
A series of previously unknown sulforaphane analogues with organofluorine substituents bonded to the sulfinyl sulfur atom, an isoselenocyanate moiety in place of the isothiocyanate group, the central sulfur atom in various oxidation states, and different numbers of methylene groups in the central alkyl chain were synthesized and fully characterized. All new compounds were tested for their biological properties in vitro and demonstrated much higher anticancer activity against two breast cancer cell lines than that shown by native sulforaphane; at the same time, the compounds were less toxic for normal cells. The influence of the particular structural changes in the molecules on the cytotoxicity is discussed. 相似文献
993.
Aleksander?Herman Sylwia?Godlewska ?ukasz?Ponikiewski Tomasz?Kruczyński Anna?Do?e?gaEmail author 《SILICON》2016,8(1):105-110
Two new methylsilylsulfides are synthesized. Propeller-like chirality is described for triaryloxysilanethiol and its methyl derivative. S-methylation of the silanethiol lowers the overall symmetry of the unit cell. 相似文献
994.
Piotr Dziubecki Piotr Grabowski Michał Krysiński Tomasz Kuczyński Krzysztof Kurowski Dawid Szejnfeld 《Journal of Grid Computing》2012,10(4):631-645
Science Gateways are web portal environments targeted for a given community and dedicated to specific scientific needs. Scientists require a different set of tools, applications, visualizations, data integration patterns, to be able to satisfy unique requirements of different research domains. To enable users to benefit from remote computational and storage resources, a web portal framework should support an easy integration and access to the e-Infrastructure. In this paper we present results of our research and development activities leading to the release of the Vine Toolkit framework integrated with Adobe Flex/BlazeDs technologies. It offers a set of unified and abstract APIs for different Grid middleware and a rich graphic presentation layer. Additionally, it automates the integration process with portal frameworks, such as Liferay or GridSphere. Vine Toolkit introduces a concept of subprojects which extend core APIs or define new low level components and web applications. This way, a Science Gateway prototyping process is definitely shortened. Consequently, it allows programmers to build software components that can be reused in a simple manner for different Science Gateways. 相似文献
995.
Extending some results by Sokó? and Lewiński (Struct Multidisc Optim 42:835–853, 2010), the optimal topology of bi-symmetric trusses with two symmetrically placed pointloads is determined analytically, and verified by highly accurate numerical calculations. It is rather remarkable that Michell’s best-known classical solution had to wait over hundred years for its generalization from one to two point loads. Some implications of these solutions, including properties of so-called O-regions, are also discussed. 相似文献
996.
Tomasz Garbowski Giulio Maier Giorgio Novati 《Structural and Multidisciplinary Optimization》2012,46(1):111-128
In this paper two procedures are developed for the identification of the parameters contained in an orthotropic elastic-plastic-hardening model for free standing foils, particularly of paper and paperboard. The experimental data considered are provided by cruciform tests and digital image correlation. A simplified version of the constitutive model proposed by Xia et al. (Int J Solids Struct 39:4053?C4071, 2002) is adopted. The inverse analysis is comparatively performed by the following alternative computational methodologies: (a)?mathematical programming by a trust-region algorithm; (b)?proper orthogonal decomposition and artificial neural network. The second procedure rests on preparatory once-for-all computations and turns out to be applicable economically and routinely in industrial environments. 相似文献
997.
We present a set of C++ classes which allow one to use the graphics card processor?s cores for quantum ab initio simulations, i.e. a direct solving of the time-dependent Schrödinger equation, gaining the benefits from the parallel architecture of the graphical processor units. We use the Chebyshev polynomial and FFT algorithm. The solution is based on NVIDIA CUDA technology. The speed-up factor in the test runs of our classes performed using the graphics card processor can even be of order of 300 in comparison with the test runs using only the single core of CPU. Not only the Schrödinger equation can be integrated using the presented solver. With only small changes it can be used for solving the nonlinear Gross–Pitaevskii equation of BEC?s dynamics, the heat equation, the diffusion equation or other parabolic partial differential equations of second order.1Program summaryProgram title: QnDynCUDACatalogue identifier: AELE_v1_0Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AELE_v1_0.htmlProgram obtainable from: CPC Program Library, Queen?s University, Belfast, N. IrelandLicensing provisions: Standard CPC licence, http://cpc.cs.qub.ac.uk/licence/licence.htmlNo. of lines in distributed program, including test data, etc.: 101 359No. of bytes in distributed program, including test data, etc.: 3 165 228Distribution format: tar.gzProgramming language: C++, C for CUDAComputer: Graphics card with CUDA technology recommendedOperating system: No limits (tested on 32-bit and 64-bit Windows and 64-bit Linux)Has the code been vectorized or parallelized?: Yes, number of processors used – one CPU core and all CUDA cores of the selected processor of graphics cardRAM: Dependent on user?s parameters, typically between several tens of megabytes and several gigabytes (this concerns also the graphics card?s memory)Supplementary material: Test input and output files (approx. 3.4 Gigabytes) are availableClassification: 2.7, 6.5Nature of problem: Solving the time-dependent Schrödinger equation.Solution method: FFT and Chebyshev polynomial algorithm, CUDA technology.Running time: Every test example included in the distribution package takes approximately an hour or so if the GPU is engaged and a day or so if only CPU is used. 相似文献
998.
Andrzej Wilk Lucyna Więcław-Solny Adam Tatarczuk Aleksander Krótki Tomasz Spietz Tadeusz Chwoła 《Korean Journal of Chemical Engineering》2017,34(8):2275-2283
Amine absorption processes are widely used to purify both refinery and process gases and natural gas. Recently, amine absorption has also been considered for application to CO2 removal from flue gases. It has a number of advantages, but there is one major disadvantage-high energy consumption. This can be solved by using an appropriate solvent. From a group of several dozen solutions, seven amine solvents based on primary amine, tertiary amine and sterically hindered amine were selected. For the selected solutions research was conducted on CO2 absorption capacity, an absorption rate and finally a solvent vapor pressure. Furthermore, tests on an absorber-desorber system were also performed. In this study the most appropriate solvent for capturing CO2 from flue gases with higher carbon dioxide concentrations was selected. 相似文献
999.
1000.
Polypropylene‐based composites containing sorbitol‐based nucleating agent and siloxane‐silsesquioxane resin 下载免费PDF全文
Monika Dobrzyńska‐Mizera Michał Dutkiewicz Tomasz Sterzyński Maria Laura Di Lorenzo 《应用聚合物科学杂志》2016,133(22)
Composites based on isotactic polypropylene (iPP) modified with a sorbitol derivative (NX8000) and siloxane‐silsesquioxane resin containing reactive phenyl groups (SiOPh) were prepared by melt extrusion. These iPP‐based formulations were investigated to evaluate the influence of such additives on the crystallization behavior and morphology, as well as on thermal and mechanical properties. The addition of sorbitol fastens crystallization kinetics of iPP and leads to higher transparency of iPP films. Upon the incorporation of siloxane‐silsesquioxane resin, no further effect on iPP crystallization kinetics is evidenced by calorimetry, optical microscopy, and X‐ray diffraction analysis. Transparency of iPP‐based composites is improved upon the addition of sorbitol, but decreased when SiOPh is added to the formulation. The composites are also stiffer, compared to neat polypropylene with a decreased elongation at break and increased Young's modulus values, with increasing amounts of fillers. The effect of the siloxane‐silsesquioxane resin on properties of iPP/NX8000/SiOPh composites was explained taking into account compatibility of the components and morphology of the composites. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43476. 相似文献