The microstructural aspects related to crystalline or amorphous structure of as-deposited and annealed films of sol-gel-derived WO 3 are shown in the literature to be critical for electrochromic (EC) performance. In consideration of ion insertion materials, there is a need for developing light and at the same time nanocrystalline structures to improve both coloration efficiency and switching kinetics. By controlling microstructure and morphology, one could design a material with optimal EC performance. This report compares the microstructural and morphological characteristics of standard WO 3 wet deposition techniques versus inkjet printing technology (IPT), correlating these features with their optical and electrochemical performances, emphasizing the importance of the dual-phase a-WO 3/TiO 2/WO X film composition proposed in this work for high-performance EC applications. The effect of the type and content of metal oxide nanoparticles in the precursor sols formulated in various peroxopolytungstic acid (PTA) and oxalic acid (OAD) proportions on film properties is comprehensively studied using multi-factorial design of experiment (DOE). To the authors' knowledge, no other report on sol-gel deposition of inorganic EC materials via the inkjet printing technique exists, in which furthermore the film crystallinity can be controlled under low-temperature process conditions. The proposed method enables development of EC films which irrespective of their composition (a-WO 3, a-WO 3/TiO 2 or a-WO 3/TiO 2/WO X) outperform their amorphous or nanocrystalline analogues presented as the state-of-the-art due to their superior chemical and physical properties. © 2012 The Royal Society of Chemistry.

Inductive superconducting fault current limiters have already demonstrated their technical viability in electrical networks. Its architecture and robustness make them potentially adequate for distribution networks, and this type of devices is considered as an enabling technology for the advent of embedded generation with renewable energy sources. In order to promote the growth and maturity of these superconducting technologies, fast design tools must be developed, allowing simulating devices with different materials in grids with diverse characteristics. This work presents advances in the development of such tool, which, at present stage, is an effective alternative to software simulations by finite elements methods, reducing dramatically computation time. The algorithms are now compared with experimental results from a laboratory scale prototype, showing the need to refine them.

Reduction in the accumulation capacitance value was more in Si metal-oxide-semiconductor devices than that of Ge metal-oxide-semiconductor devices after a thermal treatment irrespective of the annealing environment. Relatively, thermal treatment in oxygen environment improves the interface quality of HfO2/Ge stacks considerably, when compared with HfO 2/Si stacks. Whereas, the forming gas annealing at a temperature of 400 °C was not so effective in improving the interface quality at HfO 2/Si stack. The presence of induced negatively charged hydrogen atom in Ge lessens the Fermi level pinning at HfO2 and Ge interface. © 2011 Elsevier B.V. All rights reserved.

In this work we present sputtered multicomponent dielectrics based on mixtures of HfO 2 and SiO 2. This way it is possible to get stable amorphous structure up to 800°C, that does not happen for pure HfO 2, for instance, that present a polycrystalline structure when deposited without any intentional substrate heating. Besides, also the band gap of the resulting films is increased when compared with pure HfO2 that theoretically is an advantage in getting a suitable band offset with the semiconductor layer on oxide TFTs. Concerning the electrical characterization, the leakage current on c-Si MIS structures is low as 10 -9 Acm -2 at 10 V. The amorphous structure of the films also lead to better dielectric/semiconductor interfaces, as suggested by C-V characteristics on GIZO MIS structures, which do not present strong variation with frequency. On other hand, the dielectric constant decreases due to the incorporation of SiO 2 and Al 2O 3. Further improvement on insulating and interface characteristics is achieved using multilayer stacks and substrate bias during deposition. © 2012 Copyright Society of Photo-Optical Instrumentation Engineers (SPIE).

This paper presents the results of a preliminary study to examine the ability of post-silicon devices for analog processing. It is focused on the latest thin-film transistors (TFTs) with amorphous gallium-indium-zinc oxide (a-GIZO) as active layer. Three circuit configurations are presented: a differential pair and two multiplier topologies. Both triode and saturation regions of operation are included in the analysis, with the devices set to remain in strong accumulation. A neural model, which is developed based on the measured data of the TFTs, is used for the circuit simulations in the Cadence Virtuoso environment. The analog multipliers simulation results are compared against the expected functional results. © 2012 IEEE.

Toxic amides, such as acrylamide, are potentially harmful to Human health, so there is great interest in the fabrication of compact and economical devices to measure their concentration in food products and effluents. The CHEmically Modified Field Effect Transistor (CHEMFET) based on amorphous silicon technology is a candidate for this type of application due to its low fabrication cost. In this article we have used a semi-empirical model of the device to predict its performance in a solution of interfering ions. The actual semiconductor unit of the sensor was fabricated by the PECVD technique in the top gate configuration. The CHEMFET simulation was performed based on the experimental current voltage curves of the semiconductor unit and on an empirical model of the polymeric membrane. Results presented here are useful for selection and design of CHEMFET membranes and provide an idea of the limitations of the amorphous CHEMFET device. In addition to the economical advantage, the small size of this prototype means it is appropriate for in situ operation and integration in a sensor array.

Spreadsheets can be viewed as programming languages for non-professional programmers. These so-called ``end-user'' programmers vastly outnumber professional programmers creating millions of new spreadsheets every year. As a programming language, spreadsheets lack support for abstraction, testing, encapsulation, or structured programming. As a result, and as numerous studies have shown, the high rate of production is accompanied by an alarming high rate of errors. Some studies report that up to 90% of real-world spreadsheets contain errors. After their initial creation, many spreadsheets turn out to be used for storing and processing increasing amounts of data and supporting increasing numbers of users over long periods of time, making them complicated systems. An emerging solution to handle the complex and evolving software systems is Model-driven Engineering (MDE). To consider models as first class entities and any software artifact as a model or a model element is one of the basic principles of MDE. We adopted some techniques from MDE to solve spreadsheet problems. Most spreadsheets (if not all) lack a proper specification or a model. Using reverse engineering techniques we are able to derive various models from legacy spreadsheets. We use functional dependencies (a formalism that allow us to define how some column values depend on other column values) as building blocks for these models. Models can be used for several spreadsheet improvements, namely refactoring, safe evolution, migration or even generation of edit assistance. The techniques presented in this work are available under the framework HAEXCEL that we developed. It is composed of online and batch tools, reusable HASKELL libraries and OpenOffice.org extensions. A study with several end-users was organized to survey the impact of the techniques we designed. The results of this study indicate that the models can bring great benefits to spreadsheet engineering helping users to commit less errors and to work faster.

KAOS is one of the most well-known goal-oriented requirements engineering approaches. Nevertheless, building large KAOS models sometimes results in incomplete and/or complex requirements models that are difficult to understand and maintain. These shortcomings often lead to an increase in costs of product development and evolution. Therefore, for large-scale systems, the ability to manage the complexity and completeness of KAOS models is essential. In this paper, we propose a metrics suite for supporting the quantitative assessment of KAOS models complexity and completeness, in order to support their early identification. We apply the metrics to an example taken from a health club system specification.

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