Solution-processed p-type oxide semiconductors have recently attracted increasing interests for the applications in low-cost optoelectronic devices and low-power consumption complementary metal-oxide-semiconductor circuits. In this work, p-type nickel oxide (NiOx) thin films were prepared using low-temperature solution process and integrated as the channel layer in thin-film transistors (TFTs). The electrical properties of NiOx TFTs, together with the characteristics of NiOx thin films, were systematically investigated as a function of annealing temperature. By introducing aqueous high-k aluminum oxide (Al2O3) gate dielectric, the electrical performance of NiOx TFT was improved significantly compared with those based on SiO2 dielectric. Particularly, the hole mobility was found to be 60 times enhancement, quantitatively from 0.07 to 4.4 cm2/V s, which is mainly beneficial from the high areal capacitance of the Al2O3 dielectric and high-quality NiOx/Al2O3 interface. This simple solution-based method for producing p-type oxide TFTs is promising for next-generation oxide-based electronic applications. © 2016 Author(s).

This paper describes the development of a novel microfluidic platform for multifactorial analysis integrating four label-free detection methods: electrical impedance, refractometry, optical absorption and fluorescence. We present the rationale for the design and the details of the microfabrication of this multifactorial hybrid microfluidic chip. The structure of the platform consists of a three-dimensionally patterned polydimethylsiloxane top part attached to a bottom SU-8 epoxy-based negative photoresist part, where microelectrodes and optical fibers are incorporated to enable impedance and optical analysis. As a proof of concept, the chip functions have been tested and explored, enabling a diversity of applications: (i) impedance-based identification of the size of micro beads, as well as counting and distinguishing of erythrocytes by their volume or membrane properties; (ii) simultaneous determination of the refractive index and optical absorption properties of solutions; and (iii) fluorescence-based bead counting. © 2016 by the authors.

Human-Computer-Interaction (HCI) is a key topic on the Accessibility area, namely in what concerns a Smart-City environment, where humans have to interact with artefacts spread all around one particular city. In the last decade HCI has experienced a significant evolution towards a desired fully natural user interface, for example in what concerns the ability to recognize a wide range of hand gestures in real-time. Some efforts have lately been made in the hardware sector in order to deploy sensors that may gather information about the human body movements, as detailed as possible. One example of this effort is the Kinect Sensor from Microsoft. Nevertheless, although these solutions provide a solution for the body movement, they lack on the details, namely the hands, given their small dimension compared to the body as a whole. In other words, the SDKs provided by the vendors of these devices usually lack on the needed details concerning hand movements that would be needed for an accurate hand gesture recognition implementation. This paper presents an extension to the Kinect SDK based on a contour analysis for the estimation of the hand position. This algorithms are then used to provide the creation of a gesture library that might be used afterwards.

Heterogeneity is omnipresent in today’s commodity computational systems, which comprise at least one multi-core Central Processing Unit (CPU) and one Graphics Processing Unit (GPU). Nonetheless, all this computing power is not being exploited in mainstream computing, as the programming of these systems entails many details of the underlying architecture and of its distinct execution models. Current research on parallel programming is addressing these issues but, still, the systems’ heterogeneity is exposed at language level.
This paper proposes a uniform framework, grounded on the Single Operation Multiple Data model, for the programming of such heterogeneous systems. The model is declarative, empowering the compiler to generate code for multiple architectures from the same source. To this extent, we designed a simple extension of the Java programming language that embodies the model, and developed a compiler that generates code for both multi-core CPUs and GPUs. A performance evaluation attests the validity of the approach that, despite being based on a simple programming model, is able to deliver performance gains on par with hand-tuned data parallel multi-threaded Java applications.

Abstract The strain rate dependent mechanical behaviour was studied for the common out-of-autoclave aerospace textile composite 5-harness-satin carbon�epoxy. End-loaded 15 � , 30 � and 45 � off-axis and 90 � compression tests were carried out at three different strain rate levels ( 4 � 10 - 4 s - 1 , 200 s - 1 and 1000 s - 1 ) to determine the effect of strain rate for transverse compression and combined transverse compression/in-plane shear loading. The dynamic tests were carried out on a split-Hopkinson pressure bar, where high speed photography and digital image correlation allowed a detailed study of the specimen deformation and failure process. Quasi-static reference tests were carried out on an electro-mechanical test machine using the same specimen type and a static \{DIC\} system. Pronounced strain rate effects on the axial stress�strain response were observed for all specimen types. Failure envelopes for the combined s 22 c - t 12 stress state were derived from the experimental data and compared with the maximum stress criterion, which appears well suited to approximate the experimental failure envelope at all strain rate levels. It was observed that the failure envelope was simply scaled up with increasing strain rate, while the overall shape was found to be strain rate independent.

Semantic Sensor Web is a new trend of research integrating Semantic Web technologies with sensor networks. It uses Semantic Web standards to describe both the data produced by the sensors, but also the sensors and their networks, which enables interoperability of sensor networks, and provides a way to formally analyze and reason about these networks. Since sensors produce data at a very high rate, they require solutions to reason efficiently about what complex events occur based on the data captured. Nevertheless, besides detecting complex events, sensor based applications also need to execute actions in response to these events, and in some cases, to execute these actions in a transactional way. In this paper we propose TRev as a solution to combine the detection of complex events with the execution of transactions for these domains. TRev is an abstract logic to model and execute reactive transactions. The logic is parametric on a pair of oracles defining the basic primitives of the domain, which makes it suitable for a wide range of applications. In this paper we provide oracle instantiations combining RDF/OWL and relational database semantics for TRev Afterwards, based on these oracles, we illustrate how TRev can be useful for these domains.

Abstract This paper proposes a hybrid methodology for the evaluation of integrated inductors sensitivity against technological/geometrical parameters variation. The obtained results are used in an optimization-based design environment for integrated inductors, as a way of guaranteeing that obtained solutions are robust against parameter variation. For the inductor characterization, a lumped element model is used, where each element value is evaluated through physics based equations. The sensitivity of the inductor characterization to parameter variations is evaluated at two levels. At the physical level, the sensitivity of the model element values to technological/geometrical parameters variations is computed through an equation-based strategy. Then, the sensitivity of the inductor characterization to the model parameter variations is obtained through a simulation-based approach, where the Richardson extrapolation technique is used for the calculation of the partial derivatives. Several examples considering the evaluation of sensitivity of both inductance and quality factor of two inductors in \{UMC130\} technology are presented. Obtained results are compared against Monte-Carlo simulations.

Abstract The strain rate dependent mechanical behaviour was studied for the common out-of-autoclave aerospace textile composite 5-harness-satin carbon–epoxy. End-loaded 15 ° , 30 ° and 45 ° off-axis and 90 ° compression tests were carried out at three different strain rate levels ( 4 × 10 - 4 s - 1 , 200 s - 1 and 1000 s - 1 ) to determine the effect of strain rate for transverse compression and combined transverse compression/in-plane shear loading. The dynamic tests were carried out on a split-Hopkinson pressure bar, where high speed photography and digital image correlation allowed a detailed study of the specimen deformation and failure process. Quasi-static reference tests were carried out on an electro-mechanical test machine using the same specimen type and a static \{DIC\} system. Pronounced strain rate effects on the axial stress–strain response were observed for all specimen types. Failure envelopes for the combined σ 22 c - τ 12 stress state were derived from the experimental data and compared with the maximum stress criterion, which appears well suited to approximate the experimental failure envelope at all strain rate levels. It was observed that the failure envelope was simply scaled up with increasing strain rate, while the overall shape was found to be strain rate independent.

Transparent electronics has gained special attention during the last few years and is today established as one of the most promising technologies for leading the next generation of flat panel display due to its excellent electronic performance. The key components are wide band gap semiconductors, where oxides of different origin play an important role, not only as passive component but also as active component, similar to what we observe in conventional semiconductors like silicon. In this paper we present the recent progress in n- and p-type oxide based thin film transistors (TFT) produced by rf magnetron sputtering and we will summarize the major milestones already achieved with this emerging and very promising technology. © 2015 IEEE.

The formulation of a bending vibration problem of an elastically restrained Bernoulli-Euler beam carrying a finite number of concentrated elements along its length is presented. In this study, the authors exploit the application of the differential evolution optimization technique to identify the torsional stiffness properties of the elastic supports of a Bernoulli-Euler beam. This hybrid strategy allows the determination of the natural frequencies and mode shapes of continuous beams, taking into account the effect of attached concentrated masses and rotational inertias, followed by a reconciliation step between the theoretical model results and the experimental ones. The proposed optimal identification of the elastic support parameters is computationally demanding if the exact eigenproblem solving is considered. Hence, the use of a Gaussian process regression as a meta-model is addressed. An experimental application is used in order to assess the accuracy of the estimated parameters throughout the comparison of the experimentally obtained natural frequency, from impact tests, and the correspondent computed eigenfrequency.

In this paper we address a solution for detecting and tolerating one of the most typical concurrency bugs: atomicity violations. More specifically, we address High-Level Atomicity Violations (HLAV). High-level atomicity violations result from the misspecification of the scope of an atomic block, by splitting it in two or more atomic blocks which may be interleaved with other atomic blocks. Figure 1 shows an example of this type of atomicity violation. The intuitive idea behind HLAV is that if two shared data items (e.g., memory locations) were both accessed inside an atomic block, they are interrelated and probably the programmer intention is that there shall be no interleavings between these two accesses. Therefore, if (in the same program) this two addresses are accessed separately in different atomic blocks, an unfortunate interleaving may cause an atomicity violation.

We have measured the x-ray spectra from highly charged Si, S and Cl ions in collisions with thin foils using a high-resolution x-ray spectrometer. The observed lines have been assigned to various transitions in H-, He- and Li-like ions. For proper identification of line positions, the theoretical calculations have been carried out using a state-of-the-art MCDF code including QED effects, with which the experimental data is in excellent agreement. We have also observed, for the first time, x-rays arising out of the decay of long-lived resonant states in the He-like ions of each species. Details will be presented.

Given a monoid defined by a presentation, and a homotopy base for the derivation graph associated to the presentation, and given an arbitrary subgroup of the monoid, we give a homotopy base (and presentation) for the subgroup. If the monoid has finite derivation type (FDT), and if under the action of the monoid on its subsets by right multiplication the strong orbit of the subgroup is finite, then we obtain a finite homotopy base for the subgroup, and hence the subgroup has FDT. As an application we prove that a regular monoid with finitely many left and right ideals has FDT if and only if all of its maximal subgroups have FDT. We use this to show that a finitely presented regular monoid with finitely many left and right ideals satisfies the homological finiteness condition FP3 if all of its maximal subgroups satisfy the condition FP_3.

http://docentes.fct.unl.pt/lblm/files/chemrev-2014-114-5273_0.pdf

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