On-demand Evaluation for Maude

Strategy annotations provide a simple mechanism for introducing some laziness in the evaluation of expressions. As an eager programming language, Maude can take advantage of them and, in fact, they are part of the language. Maude strategy annotations are lists of non-negative integers associated to function symbols which specify the ordering in which the arguments are (eventually) evaluated in function calls. A positive index enables the evaluation of an argument whereas 'zero' means that the function call has to be attempted. The use of negative indices has been proposed to express evaluation on-demand, where the demand is an attempt to match an argument term with the left-hand side of a rewrite rule. In this paper we show how to furnish Maude with the ability of dealing with on-demand strategy annotations.     

Signature analysis for fault detection of mixed-signal ICs based on dynamic power-supply current

In this paper we have investigated a unified and simultaneous fault detection method for mixed-signal integrated circuits. The method is based on the analysis of the power-supply current through the circuit under test. The analysis has been done paying attention to the dynamic behaviour of the power-supply current, in order to avoid measurement problems related to the large amount of quiescent current drop across many analog blocks.The analysis of the dynamic power-supply current entails certain problems related to the complexity of the measurement process, especially those due to the high speed of the current transients. These problems have been addressed by considering a design for test procedure based on the use of built-in dynamic current sensors.The goal of the design for test methodology proposed is to represent the Iddt through the mixed-signal IC under test by a digital signature. The paper presents some advantages of this approach such as a good tolerance to cross-talk noise and the need for only a conventional digital tester on the complete mixed-signal IC for fault detection. The analysis is illustrated with some test results.     

Microwave heating of polymers: Influence of carbon nanotubes dispersion on the microwave susceptor effectiveness

Carbon nanotubes dispersion within the polymer matrix is a very important factor to take into account when developing new nanocomposites with optimized properties. In this article, dispersion studies have been carried out with polypropylene filled with 1% of multiwall carbon nanotubes. The nanocomposites were obtained by melt compounding in a corotative twin screw extruder. Processing parameters as screw speed, screw configuration and feeding technology were modified to analyse their effect onto carbon nanotubes dispersion. Developed nanocomposites were exposed to microwave heating (5.8 GHz, 700 W, 60 min) and heating temperature was monitored. The relation between dispersion level of carbon nanotubes and heating effectiveness was studied. Microwave heating efficiency of carbon nanotubes was increased as dispersion was improved. Electrical conductivity of nanocomposites was measured and used as indirect variable of microwave heating susceptor of carbon nanotubes nanocomposites. Higher electrical conductivity indicates a better microwave susceptor propertiy of the nanocomposite. POLYM. ENG. SCI., 56:1321–1329, 2016. © 2016 Society of Plastics Engineers     

Quantifying intermediate‐frequency heterogeneities of SOFC electrodes using X‐ray computed tomography

The electrodes in solid oxide fuel cells (SOFCs) consist of three phases interconnected in three dimensions. The volume needed to describe quantitatively such microstructures depends on several lengths scales, which are functions of materials properties and fabrication methods. This work focuses on quantifying the volume needed to represent “intermediate frequency” heterogeneities in electrodes of a commercial SOFC using X‐ray computed tomography (CT) over two different length scales. Electrode volumes of 150 μm × 150 μm × 9 μm were extracted from a synchrotron‐based micro‐CT data set, with 1³ μm³ voxels. 13.6 μm × 19.8 μm × 19.4 μm of the cathode and 26.3 μm × 24.8 μm × 15.7 μm of the anode were extracted from laboratory nano‐CT data sets, both with 65³ nm³ voxels. After comparing the variation across sub‐regions for the grayscale values from the micro‐CT, and for the phase fractions and triple phase boundary densities from the nano‐CT, it was found that the sub‐region length scales needed to yield statistically similar average values were an order of magnitude larger than those expected to capture the “high frequency” heterogeneity related to the discrete nature of the three phases in electrodes. The challenge of quantifying such electrodes using available experimental methods is discussed.     

Highly Efficient Coaxial TiO2‐PtPd Tubular Nanomachines for Photocatalytic Water Purification with Multiple Locomotion Strategies

Titania is a promising photocatalyst for water purification or production of solar fuels. However, due to its large band gap, titania is photoactive solely under UV light, which accounts for less than 5% of the solar spectrum. In this work, TiO₂‐based hybrid 1D nanostructures with photocatalytic activities extended to visible light region are designed and fabricated. Highly efficient coaxial TiO₂‐PtPd‐Ni nanotubes (NTs) are fabricated by a template‐assisted electrochemical synthesis route for water remediation under UV light, visible light, and natural sunlight. These coaxial hybrid nanotubes display a 100% degradation of organic pollutant rhodamine B in only 50 min (k‐value 0.071 min^?1) and 30 min under visible light and natural sunlight, respectively. For comparison, TiO₂ nanotubes doped with Pd nanoparticles are also fabricated and they show inferior photocatalytic properties and degrading stability over time. The multicomponent design enables to actuate the hybrid NTs by using two different external energy sources, i.e., magnetic and acoustic fields. Self‐propelled, autonomous actuation in the presence of H₂O₂ is also realized. These versatile actuation modes have the potential to enable the reported photocatalytic nanomachines to work efficiently under complex environments and to be easily collected for reuse.     

Parameter selection in the design of displacement and motion functions by means of B-splines

Journal of Mechanical Science and Technology - This work analyses the incidence of the parameter selection of B-spline curves, used in the design of displacement and motion functions, on its degree...     

英国Thrybergh钢厂新建棒材盘卷生产线产品质量和过程控制

介绍了英国康力斯公司新建大盘卷棒材生产线的主要特点和技术亮点,以及配套的先进的过程控制系统,该系统使成套设备刚一进入试车投产阶段,就能够满足产品质量要求.     

Kinetic study for the development of an accelerated oxidative stability test to estimate virgin olive oil potential shelf life

This study proposes an accelerated test performed at mild temperature (40–60 °C) to measure oxidative stability and estimate the potential shelf life of extra‐virgin olive oil (EVOO). The kinetic behavior of normalized oxidation indices (PV, K₂₃₂ and K₂₇₀) and the oxidizing substrate [unsaturated fatty acids (UFA)] during storage of different virgin olive oil samples in darkness and at different temperatures (25–60 °C) is reported for the first time. PV and K₂₃₂ followed an apparent pseudo zero‐order kinetics (R² >0.951) at all the experimental temperatures in all samples, whereas the evolution of K₂₇₀ apparently better fitted a pseudo first‐order kinetics (R² >0.926). The temperature‐dependent kinetics of the oxidation indices and the UFA were well described by the linear Arrhenius equation between 25 and 60 °C (0.960< R² <0.999, p <0.05). The best correlation between loss of PUFA and increase of oxidation product indices was K₂₃₂ (0.581< R² <0.924). The time required to reach the upper limits for PV, K₂₃₂ and K₂₇₀ established for the EVOO category in the current EU legislation correlated well with temperature using a potential equation, making it possible to set up an accelerated stability test at temperatures below 60 °C to estimate the potential shelf life under normal storage temperature conditions.     

Recognition by familiarity is preserved in Parkinson's without dementia and Lewy-Body disease.

Objective: The retrieval deficit hypothesis states that the lack of deficit in recognition often observed in patients with Parkinson's disease is because of the low retrieval requirements of the task, given that these patients have retrieval and not encoding deficits. To test this hypothesis we investigated recognition memory by familiarity in Parkinson's patients and in patients with Lewy Bodies disease and Parkinson with dementia. Method: We analyzed to what extent the experimental groups were able to recognize by familiarity in a typical yes/no recognition memory task. The experimental groups were patients with early nondemented Parkinson's disease, advanced nondemented Parkinson's disease, demented Parkinson's patients, and patients with dementia with Lewy Bodies. We compared their performance with a group of young and another group of old healthy participants. The estimation of familiarity was made by analyzing recognition of word targets and distractors consisting of combinations of different letters in comparison with a condition in which targets and distractors were composed of similar letters, even though subjects were unaware of the independent variable. Results: The results indicate that familiarity was used at the same level by controls, patients with early Parkinson's disease and patients with dementia with Lewy Bodies. Although late Parkinson patients also used familiarity, its effect was only marginally significant. Patients with Parkinson's disease and dementia were not capable of using familiarity in recognition memory. Conclusions: Our results support the retrieval deficit hypothesis as Parkinson's patients without dementia show no deficit in a situation in which the retrieval requirements are minimal. (PsycINFO Database Record (c) 2010 APA, all rights reserved)