Rensselaer Polytechnic Institute

About: Rensselaer Polytechnic Institute is a education organization based out in Troy, New York, United States. It is known for research contribution in the topics: Terahertz radiation & Finite element method. The organization has 19024 authors who have published 39922 publications receiving 1414699 citations. The organization is also known as: RPI & Rensselaer Institute.

The Eckhaus and Benjamin-Feir resonance mechanisms

Abstract: A unified treatment is given of the Eckhaus mechanism of stability or instability of two-dimensional flows, which are periodic in one spatial dimension, and the Benjamin—Feir instability mechanism of the two-dimensional Stokes water wave. The method of the amplitude equation is used, following the lead of Newell in a related context. This method easily allows the analysis of the so-called side-band perturbations, which are a crucial feature of the Eckhaus and Benjamin—Feir resonance mechanisms. In particular, it is shown that Eckhaus’s result, that a periodic flow is stable only within a particular band of wavenumbers narrower than the span of the neutral curve of linearized theory, is only valid when the eigenvalues and other parameters are real. A corrected and extended form of the result is given for the general case of complex eigenvalues and coefficients. It is noted, however, that Eckhaus’s result is valid for the important examples of Taylor vortices and Benard cells.

How wetting and adhesion affect thermal conductance of a range of hydrophobic to hydrophilic aqueous interfaces.

Abstract: We quantify the strength of interfacial thermal coupling at water-solid interfaces over a broad range of surface chemistries from hydrophobic to hydrophilic using molecular simulations. We show that the Kapitza conductance is proportional to the work of adhesion---a wetting property of that interface---enabling the use of thermal transport measurements as probes of the molecular environment and bonding at an interface. Excellent agreement with experiments on similar systems [Z. B. Ge et al., Phys. Rev. Lett. 96, 186101 (2006)] highlights the convergence of simulation and experiments on these complex nanoscopic systems.

Low ballistic mobility in submicron HEMTs

Abstract: Ballistic effects in short channel high electron mobility transistors (HEMTs) greatly reduce the field effect mobility compared to that in long gate structures. This reduction is related to a finite electron acceleration time in the channel under the device gate. As an example, the field effect mobility at room temperature in 0.15-/spl mu/m gate AlGaAs/GaAs HEMTs cannot exceed 3000 cm/sup 2//V-s. These predictions are consistent with the values of the field effect mobility extracted from the measured AlGaAs/GaAs HEMT current-voltage characteristics.

Natural language interface using constrained intermediate dictionary of results

Abstract: A method for processing a natural language input provided by a user includes: providing a natural language query input to the user; performing, based on the input, a search of one or more language-based databases; providing, through a user interface, a result of the search to the user; identifying, for the one or more language-based databases, a finite number of database objects; and determining a plurality of combinations of the finite number of database objects. The one or more language-based databases include at least one metadata database including at least one of a group of information types including case information, keywords, information models, and database values.

Microbes and metals

Abstract: Many base metals and a few precious metals as well as some metalloids can be enzymatically or non-enzymatically concentrated and dispersed by microbes in their environment. Some of these activities are commercially exploited or have a potential for it. This article summarizes these activities and the commercial or potentially commercial use of some of them.