An application of statistical symptoms in machine condition diagnostics

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.     

A comparative study of the interaction between the dried ink layer and PLA film used for packaging purposes

This research aims at comparing the interactions between the water-based printing ink and polylactide (PLA) printing base. As a reference base, a polyethylene terephthalate (PET) film was chosen. The wettability of both films was investigated. The Owens–Wendt method was applied to calculate the surface free energy (SFE). The values of SFE and its polar and dispersive components were compared with the surface tension (ST) of the ink and the polar and dispersive components of ST. The wetting envelopes of the investigated PLA and PET films are presented. Finally, the bonding strength between the dried ink layer and the printing base was analyzed. The PET film exhibited higher values of SFE. However, the bonding strength between the dried ink layer and the printing base was higher for PLA films. Our results reveal that PLA films can be an excellent choice as packaging materials, with comparable or even better print quality than conventional fossil-based plastics.     

Bimetallic Pd–Cu/ZnO–Al<Subscript>2</Subscript>O<Subscript>3</Subscript> and Pd–Cu/ZrO<Subscript>2</Subscript>–Al<Subscript>2</Subscript>O<Subscript>3</Subscript> catalysts for methanol synthesis

Monometallic copper and bimetallic palladium-copper catalysts supported on ZnO–Al₂O₃ and ZrO₂–Al₂O₃ were prepared by conventional impregnation method and tested in methanol synthesis reaction under elevated pressure (3.5 MPa) in gradientless reactor at 220°C. The physicochemical properties of prepared catalytic systems were studied using BET, X-ray, TPR-H₂, TPD-NH₃ techniques. The promotion effect of palladium on catalytic activity and selectivity of copper supported catalyst in methanol synthesis reaction was proven. The highest activity of this system is explained by the Pd–Cu alloy formation.     

Organofluorine Isoselenocyanate Analogues of Sulforaphane: Synthesis and Anticancer Activity

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.     

Propeller-Like Chirality of Methyl-Tris (2,6-diisopropylphenoxy)Silylsulfide

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.     

Easy Development and Integration of Science Gateways with Vine Toolkit

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.     

New analytical benchmarks for topology optimization and their implications. Part I: bi-symmetric trusses with two point loads between supports

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.     

On calibration of orthotropic elastic-plastic constitutive models for paper foils by biaxial tests and inverse analyses

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.     

An object-oriented implementation of a solver of the time-dependent Schrödinger equation using the CUDA technology

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.     

Solvent selection for CO<Subscript>2</Subscript> capture from gases with high carbon dioxide concentration

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.