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Polls in recent elections have shown themselves to be unreliable. Instead of asking people how they will vote, what if we looked at other aspects of their behaviour which might be predictive of their voting preferences? Arash Barfar and Balaji Padmanabhan discuss their experiments with TV viewing data [ABSTRACT FROM AUTHOR]

Although astounding performance is already proven by many research papers, the widespread adoption of GaN power devices in the market is still hampered by (1) yield and reproducibility ; (2) cost ; (3) reliability. All three factors are to be considered, but to convince customers to adopt GaN power devices, proven device and product reliability is a must. Cost is kept acceptably low by growing the GaN epi stack on 6 inch and 8inch Si substrates, and by processing the GaN power device technology in standard CMOS production lines. This paper will focus on the most important intrinsic reliability mechanisms for GaN power devices. It will cover gate dielectric reliability, Ohmic contact reliability, accelerated drain stress testing (high temperature reverse bias--HTRB) and high voltage device wear-out testing (high voltage off-state stress--HVOS). Acceleration models are discussed A measurement strategy to extract valuable information about the physical properties of the buffer layers (e.g. activation energies of the traps, conduction mechanisms, ...) based on simple transmission line structures, is outlined.

Many prior publications have focused on gallium nitride (GaN) dynamic Rdson issues at room temperature, even though GaN power devices have tremendous advantages over silicon (Si) when serving at high temperatures. We show that room-temperature stable dynamic Rdson behavior does not guarantee device reliability, and it is the stable high-temperature dynamic Rdson that determines the ruggedness of the GaN power devices. With our proprietary and innovative designs and optimizations of epitaxial and device structures, we show a completely different dynamic Rdson behavior in contrast to the common trend reported in the literature: a negative dynamic Rdson trend. We demonstrate robust performance and reliability of our new cascode GaN power devices in PFC tests conducted at both room and high temperatures, at high powers, at high-frequency conditions, and in a totem-pole circuit. We speculate on a physical model to explain the observed dynamic Rdson behaviors in terms of trapping, detrapping, and back-gating effects.

In business, information is abundant. Yet, effective use of that information to inform and drive business operations is a challenge. Our industry-university collaborative project draws from a rich dataset of commercial demographics, transaction history, product features, and Service Quality Index (SQI) factors on shipping transactions at FedEx. We apply inductive methods to understand and predict customer churn in a noncontractual setting. Results identify several SQI variables as important determinants of churn across a variety of analytic approaches. Building on this we propose the design of a Business Intelligence (BI) dashboard as an innovative approach for increasing customer retention by identifying potential churners based on combinations of predictor variables such as demographics and SQI factors. This empirical study contributes to BI research and practice by demonstrating the application of data analytics to the fundamental business operations problem of customer churn.

Electrical reliability of GaN HEMT system in both the on state and the off state regime is still a fundamental problem to be solved. To get an insight for the occurrence of the current collapse phenomena in GaN HEMTs, an electro-thermal particle based device simulator consisting of a Monte Carlo-Poisson solver, self consistently coupled with an energy balance solver for both acoustic and optical phonons, was developed. We observe that the incorporation of self-heating effects leads to an increase in the vertical electric field in the gate to drain extension region which can lead to large charge trapping on the surface and also the possibility of forming cracks or pits.