The study of entry and reentry dynamics for space vehicles is very important, particularly for manned vehicles and vehicles which is carry important devices and which can be used again. There are three types for entry dynamic, ballistics entry, glide entry and skip entry. The skip entry is used in this work for describing entry dynamics and determining trajectory. The inertia coordinate system is used to derive equations of motion and determines initial condition for skip entry. The velocity and drag force for entry vehicle, where generate it during entry into earth’s atmosphere are calculated in this work. Also the deceleration during descending and determining entry angles, velocities ratio and altitude ratio have been studied. The c

This review article concentrates the light about aetiology and treatment of the periimplantitis.

The poultry industry is developing continuously and rapidly, this development takes several trends in the poultry industry, such as searching for new alternatives feed additives. The research focused on finding new alternatives feed additives, among these alternatives is Synoptic, which used to maximize the benefit of the two important compounds (probiotics and prebiotics) as these two compounds are considered one of the most alternatives feed additives, which have been used a lot in poultry feeding to maximize the value of these compounds, they were combined into one compound called synbiotic. Several studies confirm that the synbiotic effect on the intestine morphology, which, the ratio villus height and villus: crypt ratio in the

Soils that cause effective damages to engineer structures (such as pavement and foundation) are called problematic or difficult soils (include collapsible soil, expansive soil, etc.). These damages occur due to poor or unfavorited engineering properties, such as low shear strength, high compressibility, high volume changes, etc. In the case of expansive soil, the problem of the shrink-swell phenomenon, when the soil reacts with water, is more pronounced. To overcome such problems, soils can be treated or stabilized with many stabilization ways (mechanical, chemical, etc.). Such ways can amend the unfavorited soil properties. In this review, the pozzolanic materials have been selected to be presented and discussed as chem

This article conclude a theoretical study for the possibility to produce additional electric power from Iraqi steam power plants by  cutting – off high-pressure feed water heaters .  Three separated steam power plants which Dura , south –Baghdad and Nasria were studied . The investigation showed the possibity of increasing the electric power from 10 to 15% for Dura and Nasria , whereas 6% for south – Baghdad . According to the nowadays of operation to Iraqi steam power plants , the results showed that by cutting–off high  pressure feed water heaters we can generate additional electric power about 250 MW during 3-4 hrs. daily. In addition, the fuel consumption can be reduced in comparison with diesel generat