We investigate the energetics of a Brownian motor driven by position-dependent temperature, commonly known as the Büttiker-Landauer motor. Overdamped models (M=0) predict that the motor can attain Carnot efficiency. However, the overdamped limit (M-->0) contradicts the previous prediction due to the kinetic energy contribution to the heat transfer. Using molecular dynamics simulation and numeri...

Stroboscopic wavepacket basis sets [P. Bokes, F. Corsetti, R. W. Godby, Phys. Rev. Lett., 2008, 101, 046402] are specifically tailored for a description of time-dependent processes in extended systems, such as non-periodic geometries of various contacts consisting of solids and molecules. The explanation of the construction of such a basis for two simple finite systems is followed by a review o...

We develop a theory for scaling properties of quantum transport in nano-field effect transistors. Our starting point is a one-dimensional effective expression for the drain current in the Landauer-Büttiker formalism. Assuming a relatively simple total potential acting on the electrons the effective theory can be reduced to a scale-invariant form yielding a set of dimensionless control parameter...

Expanding retrieval practice (T. K. Landauer & R. A. Bjork, 1978) is regarded as a superior technique for promoting long-term retention relative to equally spaced retrieval practice. In Experiments 1 and 2, the authors found that expanding retrieval practice of vocabulary word pairs produced short-term benefits 10 min after learning, conceptually replicating Landauer and Bjork's results. Howeve...

Nielsen’s claim that “Five Users are Enough” [5] is based on a statistical formula [2] that makes unwarranted assumptions about individual differences in problem discovery, combined with optimistic setting of values for a key variable. We present the initial Landauer-Nielsen formula and recent evidence that it can fail spectacularly to calculate the required number of test users for a realistic...

A great deal of work has been done of late on the statistical modeling of word similarity relations (cf.Schütze (1992), Lund and Burgess (1996) Landauer and Dumais (1997), Lin (1998), Turney (2001)). While this has largely been viewed as an engineering task (with the notable exception of much writing on Latent Semantic Analysis (LSA)), the relative success of different approaches to constructin...