The employment of printing techniques as cost-effective methods to fabricate low cost, flexible, disposable and sustainable solar cells is intimately dependent on the substrate properties and the adequate electronic devices to be powered by them. Among such devices, there is currently a growing interest in the development of user-oriented and multipurpose systems for intelligent packaging or on-site medical diagnostics, which would greatly benefit from printable solar cells as their energy source for autonomous operation. This chapter first describes and analyzes different types of cellulose-based substrates for flexible and cost effective optoelectronic and bio devices to be powered by printed solar cells. Cellulose is one of the most promising platforms for green recyclable electronics and it is fully compatible with large-scale printing techniques, although some critical requirements must be addressed. Paper substrates exist in many forms. From common office paper, to packaging cardboard used in the food industry, or nanoscale engineered cellulose (e.g. bacterial cellulose). However, it is the structure and content of paper that determines its end use. Secondly, proof-of-concept of optoelectronic and bio devices pro-duced by inkjet printing are described and show the usefulness of solar cells as a power source or as a chemical reaction initiator for sensors.

Chemical solution deposition is a low cost, scalable and high performance technique to obtain metal oxide thin films. Recently, solution combustion synthesis has been introduced as a chemical route to reduce the processing temperature. This synthesis method takes advantage of the chemistry of the precursors as a source of energy for localized heating. According to the combustion chemistry some organic solvents can have a dual role in the reaction, acting both as solvent and fuel. In this work, we studied the role of 2-methoxyethanol in solution based synthesis of ZTO thin films and its influence on the performance of ZTO TFTs. The thermal behaviour of ZTO precursor solutions confirmed that 2-methoxyethanol acts simultaneously as a solvent and fuel, replacing the fuel function of urea. The electrical characterization of the solution based ZTO TFTs showed a slightly better performance and lower variability under positive gate bias stress when urea was not used as fuel, confirming that the excess fuel contributes negatively to the device operation and stability. Solution based ZTO TFTs demonstrated a low hysteresis ($Δ$V = −0.3 V) and a saturation mobility of 4–5 cm2 V−1 s−1.

In this paper we deal with analog active filter design using discrete components taking into consideration tolerance effects. Sensitivity analysis is performed to determine the most influential components in the considered circuit, thus relative higher precision is offered to those parameters. Further, an in-loop optimization technique is considered, thus actual IC models are handled. An application example is presented. HSpice simulation results, supported by Monte Carlo analysis, are given to highlight efficiency of the proposed selection technique.

There are many different ways to reduce the construction industry's impact on environment. The incorporation of waste in the fabrication of construction materials may be beneficial for both the waste management sector and the construction industry. The aim of this research was to investigate the use of three different waste materials (construction and demolition waste, brick powder and fly ash) as filler in asphalt mixtures. Limestone filler was used as reference material. The materials were characterized in terms of their geometrical, physical and chemical properties, and the interaction with bitumen was assessed with two mastic test methods using four different bitumens. The specific surface of waste materials shows a wide-ranging variation due to material specific shape and texture of particles. However, the Rigden voids and bitumen number tests adequately measure the stiffening effect of these materials. The delta ring and ball test results showed there is a good relation with the filler content when the results are affected by the bitumen type. The f/b ratio for a specific bitumen–filler combination can be determined from the maximum filler-to-bitumen ratio and the recommended stiffening increase. The mastics with these waste materials showed strong resistance to water damage.

Piezoelectric energy harvesting has received great attention over the last 20 years. The main goal of this work is to discuss the potential advantages of introducing non-linearities in the dynamics of a beam type piezoelectric vibration energy harvester. The described device is essentially a cantilever beam partially covered by piezoelectric material with a force electromagnetically applied to the beam. Through experimental tests it has been confirmed the benefits of introducing non-linearities in these types of systems.

Cellulosomes are sophisticated multi-enzymatic nanomachines produced by anaerobes to effectively deconstruct plant structural carbohydrates. Cellulosome assembly involves the binding of enzyme-borne dockerins (Doc) to repeated cohesin (Coh) modules located in a non-catalytic scaffoldin. Docs appended to cellulosomal enzymes generally present two similar Coh-binding interfaces supporting a dual-binding mode, which may confer increased positional adjustment of the different complex components. Ruminococcus flavefaciens’ cellulosome is assembled from a repertoire of 223 Doc-containing proteins classified into 6 groups. Recent studies revealed that Docs of groups 3 and 6 are recruited to the cellulosome via a single-binding mode mechanism with an adaptor scaffoldin. To investigate the extent to which the single-binding mode contributes to the assembly of R. flavefaciens cellulosome, the structures of two group 1 Docs bound to Cohs of primary (ScaA) and adaptor (ScaB) scaffoldins were solved. The data revealed that group 1 Docs display a conserved mechanism of Coh recognition involving a single-binding mode. Therefore, in contrast to all cellulosomes described to date, the assembly of R. flavefaciens cellulosome involves single but not dual-binding mode Docs. Thus, this work reveals a novel mechanism of cellulosome assembly and challenges the ubiquitous implication of the dual-binding mode in the acquisition of cellulosome flexibility.

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In this paper, we address the solution of the symmetric eigenvalue complementarity problem (EiCP) by treating an equivalent reformulation of finding a stationary point of a fractional quadratic program on the unit simplex. The spectral projected-gradient (SPG) method has been recommended to this optimization problem when the dimension of the symmetric EiCP is large and the accuracy of the solution is not a very important issue. We suggest a new algorithm which combines elements from the SPG method and the block active set method, where the latter was originally designed for box constrained quadratic programs. In the new algorithm the projection onto the unit simplex in the SPG method is replaced by the much cheaper projection onto a box. This can be of particular advantage for large and sparse symmetric EiCPs. Global convergence to a solution of the symmetric EiCP is established. Computational experience with medium and large symmetric EiCPs is reported to illustrate the efficacy and efficiency of the new algorithm.

Die Ausweitung von Robotertechnologien nicht nur in der Industrie, sondern zunehmend auch in Dienstleistungsbereiche, stellt große Herausforderungen an die Mensch-Roboter-Kollaboration. Der Artikel beleuchtet psychologische, soziologische, arbeitswissenschaftliche und berufspädagogische Gesichtspunkte bei der Gestaltung und dem Einsatz von Robotern in Produktion und Service. Zu diesem Zweck werden zunächst spezifische Merkmale der Mensch-Roboter-Interaktion dargestellt, um anschließend Prinzipien der Funktionsteilung zwischen Menschen und Robotern in Arbeitssystemen des Produktions- und Servicebereichs zu diskutieren. Zu berücksichtigen sind hier die Organisation gesellschaftlicher Arbeit, die spezifischen Arbeitsaufgaben sowie die Möglichkeiten und Grenzen der informationstechnischen Realisierung solcher Aufgaben. Der Artikel endet mit dem Plädoyer, bei der Entwicklung und Anwendung von Robotern arbeitswissenschaftliche Kriterien mit Ansätzen partizipativer Technikgestaltung zu kombinieren.

In this note, we consider the semigroup $O(X)$ of all order endomorphisms of an infinite chain $X$ and the subset $J$ of $O(X)$ of all transformations $\alpha$ such that $|Im(\alpha)|=|X|$. For an infinite countable chain $X$, we give a necessary and sufficient condition on $X$ for $O(X) = < J >$ to hold. We also present a sufficient condition on $X$ for $O(X) = < J >$ to hold, for an arbitrary infinite chain $X$.

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Neste artigo apresentam-se e analisam-se um conjunto de ensaios realizados em vigas de betão armado reforçadas com armaduras pós-instaladas de aço ou de FRP, incluindo os referentes a uma nova técnica (CREatE) desenvolvida na FCT NOVA. Os resultados experimentais permitiram concluir que a técnica CREatE possibilita aumentos de resistência e ductilidade consideráveis face às técnicas tradicionais.