Following spatial disorientation, animals can reorient themselves by relying on geometric cues (metric and sense) specified both by the macroscopic surface layout of an enclosed space and prominent visual landmarks in arrays. Whether spatial reorientation in arrays of landmarks is based on explicit representation of the geometric cues is a matter of debate. Here we trained homing pigeons (Colum...

0017-9310/$ see front matter 2009 Elsevier Ltd. A doi:10.1016/j.ijheatmasstransfer.2009.12.007 * Corresponding author. E-mail address: [email protected] (K. Vafai). Analytical models are utilized to investigate the thermal performance of rectangular and disk-shaped heat pipes using nanofluids. The liquid pressure, liquid velocity profile, temperature distribution of the heat pipe wall, tempera...

Miniature heat pipes are considered to be an innovative solution able to dissipate high heat with low working fluid fill charge, provide automatic temperature control, and operate with minimum energy consumption and low noise levels. A theoretical analysis on heat pipe thermal performance using Deionized water or n-pentane as the working fluid has been carried out. Analysis on the maximum heat ...

Problem. The use of road culverts is currently an effective and relatively cheap means passing surface water under the body embankment. number pipes on highways in areas with different topography approximately 1.4 per 1 km route. Road pipes, depending cross section, can be round, rectangular, oval, elliptical, arched, polycentric. following are mainly used roads: round - 87%, rectangular 9%, re...

The efficient reduction of the pulse length and the energy width of electron beams plays a crucial role in the generation of short pulses in the range of sub-picoseconds at future light sources. At the radiation source ELBE in DresdenRossendorf short pulses are required for coherent THz generation and laser-electron beam interaction experiments such as X-ray Thomson scattering. Energy dechirpin...

Calculation of fin efficiency is necessary for the design heat exchangers. This can be calculated individual finned tubes or continuous fins. Continuous fins are mostly used in plate-fin and tube exchangers (PFTHEs). In most cases, basic elements those PFTHEs circular, oval flattened pipes, which contain circular polygonal fins, as observed PFTHEs, divided into virtual Those have a rectangular ...

Human and non-human animals can use geometric information (metric information and left-right discrimination sense) to reorient themselves in an environment. The hypothesis that in so doing they rely on allocentric (map-like) representations has received wide consensus. However, theoretical models suggest that egocentric representations may represent efficient strategies for visuo-spatial naviga...

An expression for the transmitted fraction of the uniform and parallel radiation incident upon the coupler between two rectangular light pipes of different physical dimensions is derived. It is a function of the pipe dimension ratio and the angle of the incident radiation. It is shown that for radiation nearly parallel to the pipe axis, it is possible to design a coupler for any pipe dimension ...

The acoustic wave around a sound source in the near-field area presents unconventional properties in the temporal, spectral, and spatial domains due to the propagation mechanism. This paper investigates a near-field sound localizer in a small profile structure with a single microphone. The asymmetric structure around the microphone provides a distinctive spectral variation that can be recognize...