A local and global tour on MOMoT

Software and Systems Modeling - Many model transformation scenarios require flexible execution strategies as they should produce models with the highest possible quality. At the same time,...     

Type inference in stack based languages

We consider a language of operations which pass parameters by means of a stack. An algebra over the set of type signatures is introduced, which allows the type signature of a program to be obtained from the type signatures of its constituent operations.Although the theories apply in principle to any stack based language, they have been evolved with particular regard to the proposed ANSI Standard Forth language, which is currently implemented in a type free manner. We hope this work will stimulate an interest in Forth amongst those applying algebraic techniques in software engineering, and we hope to lay the theoretical foundations for implementing practical type checkers to support Forth.     

Systematic characterization of Cl2 reactive ion etchingfor improved ohmics in AlGaN/GaN HEMTs

Pre-metal-deposition reactive ion etching (RIE) was performed on an Al_0.3Ga_0.7N/AlN/GaN heterostructure in order to improve the metal-to-semiconductor contact resistance. An optimum AlGaN thickness for minimizing contact resistance was determined. An initial decrease in contact resistance with etching time was explained in terms of removal of an oxide surface layer and/or by an increase in tunnelling current with the decrease of the AlGaN thickness. The presence of a dissimilar surface layer was confirmed by an initial nonuniform etch depth rate. An increase in contact resistance for deeper etches was experienced. The increase was related to depletion of the two-dimensional (2-D) electron gas (2-DEG) under the ohmics. Etch depths were measured by atomic force microscopy (AFM). The contact resistance decreased from about 0.45 Ωmm for unetched ohmics to a minimum of 0.27 Ωmm for 70 Å etched ohmics. The initial thickness of the AlGaN layer was 250 Å. The decrease in contact resistance, without excessive complications on device processing, supports RIE etching as a viable solution to improve ohmic contact resistance in AlGaN/GaN HEMTs     

通往10 Gbps以太网的低速之路

较低的速度通常不能算是创新，但在10 Gbps以太网的领域内，两种“低速”互连标准，即LX4和CX4，正在降低实现成本，并实现新的应用。     

冷漠的灯光和火热的Guru

我已经看见了未来。它充满耀眼的光芒。这种特殊的未来的具体体现就是由Lumileds生产并打上Luxeon的品牌铛售的高亮度发光二极管，该公司把一些采用了最新技术的样机带到了我们的办公室，这给我们留下了深刻印象。     

A series active power filter based on a sinusoidalcurrent-controlled voltage-source inverter

A series active power filter working as a sinusoidal current source, in-phase with the mains voltage, has been developed and tested. The amplitude of the fundamental current in the series filter is controlled through the error signal generated between the load voltage and a pre-established reference. The control allows an effective correction of power factor, harmonic distortion and load voltage regulation. Compared with previous methods of control developed for series active filters, this method is simpler to implement because it is only required to generate a sinusoidal current, in-phase with the mains voltage, the amplitude of which is controlled through the error in the load voltage. The proposed system has been studied analytically and tested using computer simulations and experiments. In the experiments, it has been verified that the filter keeps the line current almost sinusoidal and in-phase with the line voltage supply. It also responds very quickly under sudden changes in load conditions, reaching its steady-state in about two cycles of the fundamental     

Generativity and social motives in young adults.

Different forms of generativity in the writings of E. H. Erikson (1950/1963) and J. Kotre (1984) were related to agentic and communal motives in a sample of young adults (M?=?28 yrs old). For women, the power motive related to parenting, whereas the achievement motive was associated with forms of generative expression outside of the household. The opposite pattern of achievement and power motive relationships was found for men, although in a weaker form. The affiliation–intimacy motive, on the other hand, related both to women's parenting and societal concerns. Differences in expectations and opportunities for young men and women may account for these gender differences. The results for women support D. P. McAdams's (1988) suggestions that agency and communion are important for understanding generativity. In addition, the results provide evidence that people begin to grapple with generative issues as young adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)