Urban sprawl on agricultural lands considers one of the permanent problems, which face all the governments that govern Egypt last decades, especially with the fact that all urban areas distributed on 6% of all Egyptian territories accompanied with accelerated population growth (2% yearly). Therefore, this research aims to study factors affecting urban sprawl on agricultural lands in Egypt, theoretical studies focused on understanding all aspects of the research problem (economical, demographical, political and spatial aspects

In this paper a hybrid energy system combining variable speed wind turbine, solar photovoltaic and fuel cell generation systems is presented to supply continuous power to residential power applications as stand-alone loads. The wind and photovoltaic systems are used as main energy sources while the fuel cell is used as secondary or back-up energy source. Three individual dc–dc boost converters are used to control the power flow to the load. A simple and cost effective control with dc–dc converters is used for maximum power ...

, a view to evaluate the fracture energy of concrete and to study the fracture and localization process, it is described herein this study an experimental investigation. Fracture energy for the early ages of concrete is estimated experimentally considering the weather of Kingdome of Saudi Arabia. Several experiment specimens of different ages, sizes, lengths and end head specimens are prepared and assessed. The specimens in early age are tested out to calculate the fracture energy of concrete using a direct tension test, taking into consideration the loss of energy due to the frictional process in the mechanism of experimental set up. Also the crack localization is considered during the experiment, as dealing with the localized fracture. In this experiment work, the measurements reach to the post peak softening branch of concrete using the direct tension.