Atmospheric transmission is disturbed by scintillation, where scintillation caused more beam divergence. In this work target image spot radius was calculated in presence of atmospheric scintillation. The calculation depend on few relevant equation based on atmospheric parameter (for Middle East), tracking range, expansion ratio of applied beam expander's, receiving unit lens F-number, and the laser wavelength besides photodetector parameter. At maximum target range Rmax =20 km, target image radius is at its maximum Rs=0.4 mm. As the range decreases spot radius decreases too, until the range reaches limit (4 km) at which target image spot radius at its minimum value (0.22 mm). Then as the range decreases, spot radius increases due to geometric optical law. So tracking is possible only in the range from 3 to 11 km, depending on tracking criteria. Target image size minimized to required ratio by using transfocation technique to overcome tracking filler, this technique uses zoom lens.
We find that atmospheric scintillation is affective parameter which reduced the maximum tracking range, and to avoid tracking failure at minimum and maximum range, the transfocation technique is suitable
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Background: Thymus vulgaris is a plant rich in essential oils acclaimed for the management of oxidative stress and inflammation in the organs. Meanwhile, the heavy metal lead is widely distributed in nature and continued exposure to lead acetate causes reduced fertility.Objectives: The present study aimed to investigate the effects of T. vulgaris on ovarian and uterine structural and functional characteristics in female rats exposed to lead acetate. Methods: Three groups of 18 mature Wistar albino female rats (Rattus norvegicus), 15 weeks old and weighing between 200 and 210 g, were established and handled for 60 days as follows: Group A (control group) received 0.5 mL of distilled water (DW) daily; group B received 5 mg/kg body weight (BW
... Show MoreThe present investigation was conducted to evaluate the effect of the crude extracts mixture of three plants (Tribulus terrestris, Phoenix dactylifera and Nasturtium officinale) on semen quality,sex hormones and reproductive performance of mature male mice. A group of 25 male mice given 150mg/kg/day of the powder of the plants mixture with the food for four weeks and another three groups of 25 animals each given intraperitoneal injection from each of the aqueous and ethanolic extracts with a doses 75, 150, and 300mg/kg/day for two weeks. A remarkable increase in sperm concentration and motility with a decreased abnormal morphology was obtained in the experimental groups. A significant increase in hormones level were recognized in most grou
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The aim of this research is to know the effect of two strategies of active learning, the five fingers and traffic signals, on the first grade intermediate level student's achievement and personal intelligence. The research sample was chosen from the Al- Mansour intermediate school for boys, including (101) students divided into three groups chosen randomly which represented the first experimental group (32) students, the second experimental group (34) students, and the control group (33) students. To achieve the research aims, the research prepared a physics achievement test containing (26) items, and a personal intelligence test containing (20) items. The psychometric characteristics, of the tests were checked up the following results were
... Show MoreIron , Cobalt , and Nickel powders with different particle sizes were subjected to sieving and He-Ne laser system to determine the particle size . 1wt% from each powders was blended carefully with 99wt% from Iraqi oil . Microscopic examination were carried for all samples to reveal the particle size distribution . A Siemens type SRS sequential wavelength dispersive(WDS) X-ray spectrometer was used to analyze all samples , and the XRF intensity were determined experimentally and theoretically for all suspended samples , Good agreement between theoretical and experimental results were found .
An experiment was conducted using pots (capacity of 4 kg soil/pot) in the glasshouse of Biology Dept. College of Education (Ibn Al-Haitham) University of Baghdad during 2008-2009 growing season, in order to determine the effect of different levels of urea fertilizer (Zero, 0.1, 0.2, 0.4 gm/4 kg soil in pot) these equal to (Zero, 100,200,400 kg/ha) and different levels of superphosphate fertilizer (Zero, 0.1, 0.2 gm/4kg soil in pot), these equal to (Zero, 100,200 kg/ha) on some morphological and physiological characteristics of fenugreek plant. This experiment was conducted using Completely Randomized Design (CRD) with three replications and the experiment included (36) pots. Results indicated clear increase in all studied characteristics wi
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Sludge from stone-cutting (SSC) factories and stone mines cannot be used as decorative stones, stone powder, etc. These substances are left in the environment and cause environmental problems. This study aim is to produce artificial stone composite (ASC) using sludge from stone cutting factories, cement, unsaturated resin, water, silicon carbide nanoparticles (SiC-NPs), and nano-graphene oxide (NGO) as fillers. Nano graphene oxide has a hydrophobic plate structure that water is not absorbed due to the lack of surface tension on these plates. NGO has a significant effect on the properties of artificial stone due to its high specific surface area and low density in the composite. Its uniform distribution in ASC is very low due to its hydropho
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