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
Background: The demand for esthetic orthodontic appliances is increasing; so the esthetic orthodontic archwires were introduced. Among them, Teflon and Epoxy coated stainless steel archwires. The amount of force available from the archwire depends on the structural properties and susceptibility to corrosion. All metallic alloys are changed during immersion in artificial saliva, chlorhexidine mouthwash andtoothpaste, but their behaviors differ from one type to another. They corrode at different rates, which lead to decrease the amount of force applied to the teeth. This in vitro study was designed to evaluate the corrosion pits in stainless steel archwires coated with Teflon and with Epoxy in dry and after immersion in artificial saliva, chl
... Show MoreIn the present work, radium (226Ra), thorium (232Th), potassium (40 K), and cesium (137Cs) (Bq/kg) was measured for 24 soil samples of some districts of Al-Doura city in Baghdad governorate. The gamma spectrometry method with NaI (Tl) detector was used for radiometric measurements. The average values of specific activity for 226Ra, 232Th, 40K and 137Cs in soil samples were 38.03, 42.48, 16.34 and 2.76 Bq/kg, respectively. The radiation indicators were measured and the average values recorded were 100 Bq/kg, 44.6 nGy/h, 0.27 Bq/kg, 0.373 Bq/kg, 0.219 mSv/y, 0.055 mSv/y and 0.689 Bq/kg for the parameters of radium equivalent act
... Show MoreThe financial markets are one of the sectors whose data is characterized by continuous movement in most of the times and it is constantly changing, so it is difficult to predict its trends , and this leads to the need of methods , means and techniques for making decisions, and that pushes investors and analysts in the financial markets to use various and different methods in order to reach at predicting the movement of the direction of the financial markets. In order to reach the goal of making decisions in different investments, where the algorithm of the support vector machine and the CART regression tree algorithm are used to classify the stock data in order to determine
... Show MoreIn the city of Hebron, small business industrial organizations face a major challenge related to its ability to reach, attract and sustain a sufficient number of customers in order to ensure its continuity and sustainability. The research problem is summarized in an attempt to reveal how the e-marketing could improve and support the marketing effectiveness of small business industrial organizations in the city of Hebron/Palestine. The importance of this research stems from the fact that it addresses a new knowledge branch of the field of marketing, which is electronic marketing for small business organizations, and the fact that the research highlights appropriate marketing solutions for these organizations in light of the Intern
... Show MoreBody odour is the smell caused by bacteria feeding on sweat on the skin, especially in the armpit and groin area. Fifty-four volunteers from students and employees of college of Education Ibn Al- Haitham, were surveyed. Data were obtained concerning: subject details and microbial examination. The following conclusions were reached: 1) coagulase negative Staphylococcus was the most common isolate. 2) The most effective antibiotics were amikacin, ciprofloxacin, vancomycin, cephalothin, tobramycin, gentamycin respectively and were least sensitive to methicillin and penicillin G. 3) Alum zirconium and alum chlorohydrate were the most effective antiperspirants.
This paper is concerned with studying the numerical solution for the discrete classical optimal control problem (NSDCOCP) governed by a variable coefficients nonlinear hyperbolic boundary value problem (VCNLHBVP). The DSCOCP is solved by using the Galerkin finite element method (GFEM) for the space variable and implicit finite difference scheme (GFEM-IFDS) for the time variable to get the NS for the discrete weak form (DWF) and for the discrete adjoint weak form (DSAWF) While, the gradient projection method (GRPM), also called the gradient method (GRM), or the Frank Wolfe method (FRM) are used to minimize the discrete cost function (DCF) to find the DSCOC. Within these three methods, the Armijo step option (ARMSO) or the optimal step opt
... Show MoreThe Boltzmann transport equation is solved by using two- terms approximation for pure gases and mixtures. This method of solution is used to calculate the electron energy distribution function and electric transport parameters were evaluated in the range of E/N varying from . 172152110./510.VcmENVcm
The electron energy distribution function of CF4 gas is nearly Maxwellian at (1,2)Td, and when E/N increase the distribution function is non Maxwellian. Also, the mixtures are have different energy values depending on transport energy between electron and molecule through the collisions. Behavior of electrons transport parameters is nearly from the experimental results in references. The drift velocity of electron in carbon tetraflouride i
Provides the style of benchmarking the best possible use whenevaluating the performance and evaluation, as well as improved performance,due to its consistency with the principles of good evaluation of theperformance, an extension of the completion of several functions of the timeand cost less, thereby increasing the efficiency of the management of theinstitutions, especially institutions, the media, as it became public the future ofthe message sender to the same time Zaorosaúl new media is challenging thetraditional media of what distinguishes this new interactive media and mass ledto this transition . However, the media Aljdidhoosaúl traditional mediacontinue to coexist and reinforce each Menhmaalakhr, for his wealth offreedom of opin
... Show MoreThe study aimed to identify the awareness degree of teacher students in the department of Arabic language and their supervisors at Al-aqsa University for their future roles in the age of knowledge. To achieve this objective, descriptive- analytical approach was used. The instruments of this study were two questionnaires: first one consist of (20) item for teacher students, and the second consist of (27) item for educational supervisors which covered three roles: professional, technological, and humanitarian. The sample was (120) student selected randomly, and (39) supervisors of Arabic language. The result revealed that the mean of degree awareness of teacher students and their supervisors of future role are (3.857), (3.472) respectively
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