Multiple linear regressions are concerned with studying and analyzing the relationship between the dependent variable and a set of explanatory variables. From this relationship the values of variables are predicted. In this paper the multiple linear regression model and three covariates were studied in the presence of the problem of auto-correlation of errors when the random error distributed the distribution of exponential. Three methods were compared (general least squares, M robust, and Laplace robust method). We have employed the simulation studies and calculated the statistical standard mean squares error with sample sizes (15, 30, 60, 100). Further we applied the best method on the real experiment data representing the varieties of cigarettes according to the US Federal Trade Commission.
The mineralogical investigation, geochemical analysis, and grain size calculation were carried out for floodplain sediment in the Tigris River to identify the properties of the sediment. The average values of the three main sediment classes, very fine sand, silt, and clay are 9.67, 62.53 and 27.80%, respectively. The silt size fraction was predominant. The classification and nomenclature of surface sediment types from the floodplain of the Tigris River are sandy-silt and mud, and they are the dominant sediment. Statistical parameters of grain size analysis refer to the average of the median values 3.74 Φ very fine sand; mean in average 6.16 Φ coarse silt; standard deviation evident by average 1.30 Φ poorly sorted, skewed; in
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The aim of this study was to identify the impact of the Knowledge Management Processes on organizational creativity in the Airlines Companies working in Sudan. The hypotheses formulated as:, there is a positive relationship statistically significant differences between knowledge management processes (diagnosis, the acquisition, storage, distribution and application) and organizational creativity. the measurement of the variables had been adopted from previous studies. The study used a Descriptive approach and and the analytical statistical method to construct the model and SPSS Program for data analysis .Purposive sample procedure had been chosen and structured questionnaire had been developed. Out of 215 q
... Show MoreFreshwater mussels are a guild of stationary, suspended-feeding species; they perform significant ecological functions like nitrogen cycling, bioturbation that gives oxygen and habitat that other creatures need to survive, and increasing water clearance by filtration. Knowledge of the freshwater mussel Unio tigridis Bourguignat, 1852, distribution, and molecular study in Iraq was inadequate. In the current study, this species of freshwater Mussels belonging to the family Unionidae was collected from different locations in the Greater Zab River, from April 2022 to November 2022. The average water temperature of the site was arranged between (17.8 to 36.1 C°). All previous studies in the Kurdistan Region and Iraq were based on morphologic
... Show MoreTemperature inside the vehicle cabin is very important to provide comfortable conditions to the car passengers. Temperature inside the cabin will be increased, when the car is left or parked directly under the sunlight. Experimental studies were performed in Baghdad, Iraq (33.3 oN, 44.4 oE) to investigate the effects of solar radiation on car cabin components (dashboard, steering wheel, seat, and inside air). The test vehicle was oriented to face south to ensure maximum (thermal) sun load on the front windscreen. Six different parking conditions were investigated. A suggested car cover was examined experimentally. The measurements were recorded for clear sky summer days started at 8 A.M. till 5 P.M.
... Show MoreShatt al-Arab is the only navigational artery in Iraq, extending from the city of Qurna to its mouth in the Arabian Gulf at the city of Al-Fao within the governorate of Basrah for a length of approximately 204 km. Its width ranges from 400 m to 2000 m, and its depth ranges from 8 m to 20 m. The southern part of it, 93 km long from Umm al-Rassas Island to Ras al-Bisha, represents the international border between Iraq and Iran, where the Thalweg line represents the border between the two countries, which is the deepest point in the riverbed (according to the 1975 Algiers Agreement). The western bank (the Iraqi side) within the common border of Shatt al-Arab is subject to continuous erosion, which leads to the shifting of t
... Show MoreThis paper reviews the distribution range of wild goat Capra aegagrus (Erxleben, 1777) in Iraq with new sighting of very small herd of wild goat occur in Alqosh mountain, north of Nineveh province, where wild goat have a little informations on the distribution areas in Iraq according to the Red List of the International Union for Conservation of Nature (IUCN).
Seasonal variations of the species composition and abundance of Cladocera were studied in two stations at the end of the Tigris River and one station at the confluence of the Tigris with Euphrates area, at the beginning of the Shatt Al-Arab River in Al-Qurnah North of Basrah Province, from October 2015 to August 2016. Samples of zooplankton were collected by plankton net 100-µm. mesh size. The population density of Cladocera ranged between 1 Ind /m³ during summer and 211 Ind./m³ during winter at station 1 (Al-Jewaber Bridge). A total of 16 species of Cladocera belonging to 12 genera were recorded in the study. The average density of Cladocera ranged from 23.2 ind./m3 at Station 2 (Hamayon Bridge) to 53.7 Ind./m3
... Show MoreThis study aimed to detect antibiotics in water, particulate, plant, and sediment in the Tigris River within Baghdad City, in addition to their spatiotemporal variations, and related physicochemical parameters. Five sites were selected in the river. Three target antibiotics (tetracycline, gentamycin, and ciprofloxacin) were detected in water, particulate, plant, and sediment of the river at all selected sites. The results clearly showed that the concentrations of target antibiotics were sediment > water > plant > particulate. Site 3 is considered as a risk site where high concentrations of all antibiotics during the wet and dry seasons wer
In the present paper, a simply* compact spaces was introduced it defined over simply*- open set previous knowledge and we study the relation between the simply* separation axioms and the compactness, in addition to introduce a new types of functions known as 𝛼𝑆 𝑀∗ _irresolte , 𝛼𝑆 𝑀∗ __𝑐𝑜𝑛𝑡𝑖𝑛𝑢𝑜𝑢𝑠 and 𝑅 𝑆 𝑀∗ _ continuous, which are defined between two topological spaces.
This study aimed to extract, purify, and characterize the protease of local Okra Abelmoschus esculentus pods. The extraction process was conducted using ten extraction solutions with different pH and ionic strength values. Phosphate buffer solution with (pH 7, 0.05M, containing 2% sodium chloride) gave the highest activity which was (7.2 Unit/ml) as compared to other solutions, which ranged from 0.8-5.9 Unit/ml. The extracted enzyme purified by several stages. Being, precipitation by gradual addition of Ammonium sulphate from 20 to 85% saturation, then the precipitated enzyme was dialyzed and fractionated through DEAE-Cellulose (22X1.1cm), the enzymic fractions were pooled. The specific activity, purification fold and the enzyme yield value
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