URING 1937 some abnormal chicks appeared among the progenies of two D different breeding pens of our experimental flock of fowls. These chicks showed a close outward resemblance to specimens of the dominant rumpless variation and its intermediate modifications (DUNN 1925; LANDAUER and DUNN 1925; LANDAUER 1928). The simultaneous occurrence of a number of such rumpless birds suggested that we wer...

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...

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...

A commercial optically stimulated luminescence (OSL) system developed for radiation protection dosimetry by Landauer, Inc., the InLight microStar reader, was tested for dosimetry procedures in radiotherapy. The system uses carbon-doped aluminum oxide, Al2O3:C, as a radiation detector material. Using this OSL system, a percent depth dose curve for 60Co gamma radiation was measured in solid water...