Background/objectives: To study the motion equation under all perturbations effect for Low Earth Orbit (LEO) satellite. Predicting a satellite’s orbit is an important part of mission exploration. Methodology: Using 4th order Runge–Kutta’s method this equation was integrated numerically. In this study, the accurate perturbed value of orbital elements was calculated by using sub-steps number m during one revolution, also different step numbers nnn during 400 revolutions. The predication algorithm was applied and orbital elements changing were analyzed. The satellite in LEO influences by drag more than other perturbations regardless nnn through semi-major axis and eccentricity reducing. Findings and novelty/improvement: The results demonstrated that when m for Runge–Kutta’s method is large; the perturbed value for orbital element considers more acceptable. Furthermore, as nnn increases the step will reduce.
A single specimen of the African catfish, Clarias gariepinus, was recorded for the first time in Baghdad, Iraq. The specimen was caught during a fish survey to document some local species in northern Baghdad (Al-Rusafa) on March 21, 2023. The total length of the specimen was 43 cm, and its weight was 590 grams. Some biometric measurements of the specimen were studied and found to be consistent with the general characteristics of the African catfish Clarias gariepinus (Burchell, 1822). It is possible that the fish entered Iraqi inland waters, specifically from the Euphrates River via Syria or from the Tigris River via Turkey.
Many researchers consider Homogeneous Charge Compression Ignition (HCCI) engine mode as a promising alternative to combustion in Spark Ignition and Compression Ignition Engines. The HCCI engine runs on lean mixtures of fuel and air, and the combustion is produced from the fuel autoignition instead of ignited by a spark. This combustion mode was investigated in this paper. A variable compression ratio, spark ignition engine type TD110 was used in the experiments. The tested fuel was Iraqi conventional gasoline (ON=82).
The results showed that HCCI engine can run in very lean equivalence ratios. The brake specific fuel consumption was reduced about 28% compared with a spark ignition engine. The experimental tests showed that the em
... Show MoreFreshwater scarcity poses a global challenge, particularly in regions where conventional water resources are limited. Solar stills offer an economical, sustainable solution; however, their yield is limited. This study aims to evaluate a new tracking concentrated tilted tubular solar still equipped with a heat‐pipe TTSS‐HP. The novelty of the present work lies in four aspects: a novel trough U‐channel design that improves the interception of reflected solar radiation, a novel hexagonal glass cover design. A receiver formed of four‐sections, combined with a heat‐pipe and dual trough concentrators. Outdoor experiments are carried out in Baghdad, Iraq (33.27° N, 44.37° E),
Inthis study new derivatives of Schiff bases and nucleoside analogues have been synthesized from the starting material D-glucose after a series of reactions. Derivative 1 was prepared from D-glucose then react with P-bromoacetophenone gave derivative 2 was reacted with dimethyl sulfoxide and acetic anhydride for dehydration a molecule of water gave 3. The spiro ring was prepared at 3-position from the reaction of 3 derivative with 1-phenyl-2–thioureagave 4. The protection group at 1 position was removed by using acetic acid fllowed by periodate oxidation to obtain 6. Reaction of 6 with hydrazide derivative at once and dtriazole derivative at another gave 8 and 9 respectively. Compound 6 was reduced to gave derivative 7. The 1-hydroxylgrou
... Show MoreAbstract The aim of this research is to show the grade of implementation of ISO 26000 (Social Responsibility Standard), specifically which related in clause sex (consumer issues), this study was achieved in Market Research and Consumer Protection Center (MRCPC) / University of Baghdad. The seven consumer issues of ISO 26000 was analyzed to show the extent of its implementation in MRCPC depending of using a check list as a principle instrument to collect research data and information. Results analysis was achieved by percentages and mean average. The research was leaded some of results and the most importance one was that the grade of implementation of the center in related to consumer issues given in the standard was medium
ABSTRUCT
The main aim of this research has been associated with the study of relationship between competitive intelligence and strategic risk, and to deduct their specific trends, which are interpreted as predicted by research hypotheses according to a review of literature including prior studies. The basic theme of these hypotheses is related to the probability that declining levels of strategic risk and competitive positions of industrial companies is dependent upon the growing capacity to stay ahead of competitors in the market.
A purposive non-random
... Show MoreNew Schiff base, namely [2-(carboxy methylene-amino)-phenyl imino] acetic acid (L) and its some metal complexes [LCo.2H2O], [LNi.2H2O], [LCu].3H2O, [LCd.2H2O], [LHg.2H2O] and [LPb.2H2O], were reported and characterized by elemental analysis, metal content, spectroscopic methods, magnetic moments and conductivity measurements, it is found that the geometrical structures of these complexes are octahedral [Co(II), Ni(II), Cd(II), Hg(II), Pb(II) and square planar Cu(II).The complexes have been found to posses 1:1 (M:L) stoichiometry