The present wind tunnel particle image velocimetry (PIV) measurements document flows around flat and steep street canyons subject to thermal conditions at different levels, ranging from the Richardson number of 0.31 2.07. A steepness ratio, that is, ratio windward leeward building heights, is proposed characterise geometrical influence surrounded by buildings non-uniform height. To study effect...

A reading-based CAPTCHA, called ‘ScatterType,’ designed to resist character–segmentation attacks, is described. Its challenges are pseudorandomly synthesized images of text strings rendered in machine-print typefaces: within each image, characters are fragmented using horizontal and vertical cuts, and the fragments are scattered by vertical and horizontal displacements. This scattering is desig...

High concentrations ofparticulate matter are frequently reported in submarine canyons. This study demonstrates that in Baltimore submarine canyon, elevated concentrations result from periodic resuspension events. The sloping bottom and V-shaped topography of submarine canyons could accelerate tidal flows in the canyon axis sufficiently to cause resuspension, which occurs predominantly at tidal ...

Many avian species are negatively impacted by urbanization, but other species survive and prosper in urbanized areas. One factor potentially contributing to the success of some species in urban areas is the reduced presence of predators or parasite vectors in urban compared to rural areas. In addition, urban areas may provide increased food and water resources, which can enhance immune capacity...

High sensitivity multi-constellation GNSS receivers can dramatically improve the satellite availability in an urban environment. However, positioning accuracy remains a challenge because of blockage, reflection and diffraction of signals by buildings. In typical urban positioning scenarios, the receiver often receives a mixture of nonline-of-sight (NLOS) signals, multipath-contaminated direct l...

We reiterate that geological observations do not require Grand Canyon carving coeval with Colorado River integration. (U-Th)/He data from the western canyon, totaling 29 reproducible analyses from six samples and two labs, compellingly support an ancient canyon. Three dispersed analyses from one anomalous sample do not refute this conclusion, nor do the claimed shortcomings of our modeling have...

The influence of various tree planting configurations on tracer gas dispersion in an urban street canyon is studied numerically, using OpenFOAM Large Eddy Simulation (LES). A recycling and rescaling turbulent inflow generation method implemented validated against a canonical backwards-facing step case. simulations are based the CODASC experiments, where was emitted from line sources at level. e...

Kentsel mekanda yüksek binalar ve sokakların oluşturduğu kent formu kanyonu olarak tanımlanmaktadır. Bu mekanların geometrik özelliklerinden kaynaklı unsurlar dış mekan ısıl durumu üzerinde etkiye sahiptir. yüzden bu çalışmada sıcak-nemli Adana dokusunda yer alan Kurtuluş Mahallesi’ndeki kanyonlarının uydu görüntüleri aracılığı ile durumlarının tespit edilmesi amaçlanmıştır. Çalışmanın yöntemi ...

Japan has been developing a new satellite based positioning system called Quasi-Zenith Satellite System (QZSS). Since improvement of positioning availability in urban area is one of the most important advantages of the QZSS, multipath mitigation is a key factor for the QZSS positioning system. Therefore, Japan Aerospace Exploration Agency (JAXA) and GNSS Inc. developed a pseudolite, which trans...