[1] We report measurements of the x-ray emission from rocket-triggered lightning, made during the summer of 2003, using four instruments placed between 15 and 40 m from the lightning channels. X-rays were measured 0–80 ms just prior to and at the beginning of 73% of the 26 return strokes observed. The emission was composed of multiple, very brief bursts of x-rays in the 30–250 keV range, with e...

A hydroquinone/tretinoin (HQ/tret) skin care system designed for use with non-surgical facial rejuvenation procedures has recently become available. In this observer-masked study, 36 patients with moderate-to-severe wrinkling of the skin around the eyes and lips were randomly assigned to use either the 4% hydroquinone/0.05% tretinoin skin care system or placebo products, each day for 90 days. I...

wind regime and sand grain size are two of the factors that determine the morphology and dynamics of sand dunes in desert areas. regarding the importance of wind effects on sand dunes especially in iran, in this study, khartooran erg was analyzed to determine wind direction and to detect sand source sites. khartooran erg is located on eastern north of iran and lies in khorasan razavi and semnan...

abstract wind erosion of soils and suspended particles in iran is one of the serious environmental and agricultural problems which affect agricultural lands, water reservoirs, irrigation canals, drains and etc. therefore wind erosion control needs attention specially in arid and semi-arid regions. although in recent years, some polymeric materials have been used for improvement of structural st...

In Northern Europe, Scandinavia and in mountainous areas elsewhere in Europe, a considerable portion of road accidents has adverse weather (e.g. strong winds, snow and ice) as a primary or a contributing cause. In future climate, wind will probably appear as a more serious and frequent threat to road traffic than in present climate. Another consequence of climate change on road traffic is the n...

Wind farm control design is a recently new area of research that has rapidly become key enabler for the development large wind projects and their safe efficient connection to power grid. A comprehensive review intense conducted in this over last 10 years presented. Part I reviews system concepts structures classifies them depending on main objective (i.e. maximise production or provide grid ser...

Machine learning algorithms are applied to predict intense wind shear from the Doppler LiDAR data located at Hong Kong International Airport. Forecasting in vicinity of airport runways is vital order make intelligent management and timely flight operation decisions. To time series shear, Bayesian optimized machine models such as adaptive boosting, light gradient boosting machine, categorical ex...