نتایج جستجو برای: sand

تعداد نتایج: 28228  

2004
Bedrich Benes Toney Roa

An algorithm for simulating wind-ripples and moving sand is extended by the detection of fixed objects. This permits us simulation and animation of sand interacting with objects like houses, highways, cactuses, etc. Sand is accumulated on the windward side of an obstacle and the sand relocation and wind-ripples formation is diminished on the leeward side. The wind shadow depends on the object’s...

1998
Zongying He Shenggong Li Yoshinobu Harazono

Horqin Sandy Land is located in northeast China (4241’-4515’N, 11835’-12330’E). The wind-sand topography in Horqin Sandy Land can be described as two series--sand deposition and wind erosion. Wind is the natural force for the formation of wind-sandy environment, under windsandy environment, the wind erosion processes such as sand drifting, dust-storm, etc. occurred frequently because of the fre...

Journal: :Analytical sciences : the international journal of the Japan Society for Analytical Chemistry 2003
Chiaki Igarashi Naotatsu Shikazono

The major element composition, including two kinds of clay minerals and moisture content of sound-producing sand are reported for the first time. Sand from 33 beaches in Japan has been found to make sound. Ten sound-producing beaches were selected to compare with silent beach sand. Both sound-producing sand and silent beach sand are mostly composed of quartz and feldspar. The range of SiO2 cont...

2004
Attila A. Németh

Offshore activities often encounter large scale sand patterns, such as sand waves. Sand waves are offshore bed forms occurring at water depths of 10 to 50 m. Their wavelengths can lead up to 500 m and their heights are typically several metres. Furthermore, sand waves have been shown to migrate, with typical velocities of up to metres per year. These dynamic sand waves decrease the least naviga...

Journal: :Epidemiology 2012
Christopher D Heaney Elizabeth Sams Alfred P Dufour Kristen P Brenner Richard A Haugland Eunice Chern Steve Wing Stephen Marshall David C Love Marc Serre Rachel Noble Timothy J Wade

BACKGROUND Beach sand can harbor fecal indicator organisms and pathogens, but enteric illness risk associated with sand contact remains unclear. METHODS In 2007, visitors at 2 recreational marine beaches were asked on the day of their visit about sand contact. Ten to 12 days later, participants answered questions about health symptoms since the visit. F+ coliphage, Enterococcus, Bacteroidales...

2015
Shengbo Xie Jianjun Qu Yuanming Lai Xiangtian Xu Yingjun Pang

Previous research has shown that the temperature of underlying permafrost decreases after the ground surface is covered with sand. No significant conclusions have yet been drawn that explain why this happens, because the heat transfer mechanism effects of the sand layer on the underlying permafrost remain unclear. These mechanisms were studied in the present work. We found that the upward short...

2008
X. J. Zheng

In the evolution processes of wind blown sand movement and aeolian geomorphology, it always contains some complex behaviors, for example, the nonlinear character of turbulence and attractors, the stochastic character of wind gust, liftoff and movement of sand, the interaction among wind field, sand movement, electric field in wind blown sand flux and thermal diffusion, multi-scale character fro...

Journal: :The European physical journal. E, Soft matter 2013
Ning Huang Xianpan Xia Ding Tong

Straw checkerboard barrier (SCB) is the most representative antidesertification measure and plays a significant role in antidesertification projects. Large-eddy simulation and discrete-particle tracing were used to numerically simulate the wind sand movement inside the straw checkerboard barrier (SCB), study the movement characteristics of sand particles, find the transverse velocities of sand ...

Journal: :Complex Systems 1996
Jérôme Olivier Durand-Lose

We study the evolution of a one-dimensional pile, empty at rst, which receives a grain in its rst stack at each iteration. The nal position of grains is singular: grains are sorted according to their parity. They are sorted on trapezoidal areas alternating on both sides of a diagonal line of slope p 2. This is explained and proved by means of a local study. Each generated pile, encoded in heigh...

2013
A. Jayaraman

Abstract— In recent days the demand for river sand is increasing due to its lesser availability. Hence the practice of replacing river sand with M-Sand is taking a tremendous growth. It is also inferred from the literature that replacement of normal sand with M-Sand produces no appreciable increase in compressive strength due to the variation in the pore size of concrete at micro level. This pa...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید