Inkjet Printing of Functional Electronic Memory Cells: A Step Forward to Green Electronics

open access journalNowadays, the environmental issues surrounding the production of electronics, from the perspectives of both the materials used and the manufacturing process, are of major concern. The usage, storage, disposal protocol and volume of waste material continue to increase the environmental footprint of our increasingly “throw away society”. Almost ironically, society is increasingly involved in pollution prevention, resource consumption issues and post-consumer waste management. Clearly, a dichotomy between environmentally aware usage and consumerism exists. The current technology used to manufacture functional materials and electronic devices requires high temperatures for material deposition processes, which results in the generation of harmful chemicals and radiation. With such issues in mind, it is imperative to explore new electronic functional materials and new manufacturing pathways. Here, we explore the potential of additive layer manufacturing, inkjet printing technology which provides an innovative manufacturing pathway for functional materials (metal nanoparticles and polymers), and explore a fully printed two terminal electronic memory cell. In this work, inkjetable materials (silver (Ag) and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS)) were first printed by a piezoelectric Epson Stylus P50 inkjet printer as stand-alone layers, and secondly as part of a metal (Ag)/active layer (PEDOT:PSS)/metal (Ag) crossbar architecture. The quality of the individual multi-layers of the printed Ag and PEDOT:PSS was first evaluated via optical microscopy and scanning electron microscopy (SEM). Furthermore, an electrical characterisation of the printed memory elements was performed using an HP4140B picoammeter

Flexible glass substrates with via holes for TFT backplanes

This paper looks at flexible glass substrates with via holes for TFT backplane

Enhancement of SSVEPs Classification in BCI-based Wearable Instrumentation Through Machine Learning Techniques

This work addresses the adoption of Machine Learning classifiers and Convolutional Neural Networks to improve the performance of highly wearable, single-channel instrumentation for Brain-Computer Interfaces. The proposed measurement system is based on the classification of Steady-State Visually Evoked Potentials (SSVEPs). In particular, Head-Mounted Displays for Augmented Reality are used to generate and display the flickering stimuli for the SSVEPs elicitation. Four experiments were conducted by employing, in turn, a different Head-Mounted Display. For each experiment, two different algorithms were applied and compared with the state-of-the-art-techniques. Furthermore, the impact of different Augmented Reality technologies in the elicitation and classification of SSVEPs was also explored. The experimental metrological characterization demonstrates (i) that the proposed Machine Learning-based processing strategies provide a significant enhancement of the SSVEP classification accuracy with respect to the state of the art, and (ii) that choosing an adequate Head-Mounted Display is crucial to obtain acceptable performance. Finally, it is also shown that the adoption of inter-subjective validation strategies such as the Leave-One-Subject-Out Cross Validation successfully leads to an increase in the inter-individual 1-σ reproducibility: this, in turn, anticipates an easier development of ready-to-use systems

Where are the world's top 100 I.T. firms - and why?

Various publications tabulate and publish lists of the ?top 100? information-technology (I.T.) firms. The July 1997 issue of PD Magazine, for example, has a list showing that most of the world?s key firms in computing, software, semiconductors, and related fields are American. They are also heavily concentrated in such western states as Texas, Utah, Washington, and of course California. The distribution of firms and entrepreneurs is markedly different from 15 years ago. For example, the December 1997 Upside Magazine list of the top 100 people in I.T. contains only three individuals from supposedly ?high-tech? Massachusetts ? or no more than the number predicted by the state?s share of the US population. The paper will extend my work tracking the westward rebirth of American computing since the early 1980s. It will complement the employment shifts I have already documented with new mappings of firms and entrepreneurs. The hypotheses is that the PC revolution spurs a regional realignment of US computing away from the more hierarchical and bureaucratized firms of the Northeast to flatter, more agile, and more entrepreneurial firms in the younger economic cultures of the West. A look at the specific enterprises and entrepreneurs will illuminate the process by which the US regained its leadership in I.T. within the world economy.

The Dynamics of Brand Equity: A Hedonic Regression Approach to the Laser Printer Market

The authors develop a dynamic approach to measuring the evolution of comparative brand premium, an important component of brand equity. A comparative brand premium is defined as the pairwise price difference between two products being identical in every respect but brand. The model is based on hedonic regressions and grounded in economic theory. In constrast to existing approaches, the authors explicitly take into account and model the dynamics of the brand premia. By exploiting the premia’s intertemporal dependence structure, the Bayesian estimation method produces more accurate estimators of the time paths of the brand premia than other methods. In addition, the authors present a novel yet straightforward way to construct confidence bands that cover the entire time series of brand premia with high probability. The data required for estimation are readily available, cheap, and observable on the market under investigation. The authors apply the dynamic hedonic regression to a large and detailed data set about laser printers gathered on a monthly basis over a four-year period. It transpires that, in general, the estimated brand premia change only gradually from period to period. Nevertheless the method can diagnose sudden downturns of a comparative brand premium. The authors’ dynamic hedonic regression approach facilitates the practical evaluation of brand management.brand equity, price premium, hedonic regression, Bayesian estimation, dynamic linear model