This paper is concerned with pre-test single and double stage shrunken estimators for the mean (?) of normal distribution when a prior estimate (?0) of the actule value (?) is available, using specifying shrinkage weight factors ?(?) as well as pre-test region (R). Expressions for the Bias [B(?)], mean squared error [MSE(?)], Efficiency [EFF(?)] and Expected sample size [E(n/?)] of proposed estimators are derived. Numerical results and conclusions are drawn about selection different constants included in these expressions. Comparisons between suggested estimators, with respect to classical estimators in the sense of Bias and Relative Efficiency, are given. Furthermore, comparisons with the earlier existing works are drawn.
Academic boredom is one of the most emotional problems that arouse an individual's fatigueness and lowers his interest. This is because of the environment's low efficiency and of spending long monotonous time. This state is characterized by having lack of interest, difficulties in concentration, and the desire to leave the class. It is considered one of the most prominent forms of boredom widespread among students and the most severe and dangerous one that has negative effects and severe psychological and social problems. The current research aims to investigate a randomly selected sample of 335 students from the first and third grades at the directorates of education (Karkh and Rusafa) who suffers from academic boredom. Similarily
... Show MoreThe present study was conducted to determine the pathogenicity of Paecilomyces farinosus as biocontrol agents against Tragoderma granarium (khapra) under laboratory conditions with three concentrations ( 2.8 x 108 , 2.8 x 106 ,2.8 x104 spores/ ml). The laboratory results revealed that fungi showed it's higher pathogencity to larve stage on 2nd instar and 6th instar , although their capability differs according to the fungi concentrations this fungi caused higher mortality of 2nd larval instar 70% and 60% ,55% when it was used at concentrations 2 .8 x 106 ,2.8 x104 spores/ ml respectively. On the other hand on 6th larval instars 55% , 35% , 30% at concentrations ( 2.8 x 108 , 2.8 x 106 ,2.8 x104 spores/ ml) respectively, and the h
... Show MoreThe present study introduced a new description of the last larval instar of the oak tree borer, Latipalpis johanidesi Niehuis, 2002 (Coleoptera, Buprestidae). The larval specimens were collected from the oak trees within the mountainous areas, Erbil governorate, Iraqi Kurdistan Region, during the beginning of April till the end of May 2019.
Schematic sketches were provided to illustrate unclear morphological features, and the results presented importance morphological evidence for confirming the identification of this species in the larval stage precisely.
Inferential methods of statistical distributions have reached a high level of interest in recent years. However, in real life, data can follow more than one distribution, and then mixture models must be fitted to such data. One of which is a finite mixture of Rayleigh distribution that is widely used in modelling lifetime data in many fields, such as medicine, agriculture and engineering. In this paper, we proposed a new Bayesian frameworks by assuming conjugate priors for the square of the component parameters. We used this prior distribution in the classical Bayesian, Metropolis-hasting (MH) and Gibbs sampler methods. The performance of these techniques were assessed by conducting data which was generated from two and three-component mixt
... Show MoreThe aim of the research was to prepare a scale of obstacles to achieving quality performance, field application from the point of view of fourth-stage female students, to identifyOn the difficulties and obstacles to achieving quality performance through field application from the students’ point of view for the topic (school administrative procedures, learners, cognitive achievement, school tools).The researchers used the descriptive approach in the research procedures as it is an appropriate approach to achieve the research objectives.,The following questions were asked:There are obstacles and difficulties faced by female students during the process of choosing schools, dealing with school administrations, and the difficulties fa
... Show MoreThe ability of single and mixed bacterial culture to utilize Dora-refineries petroleum wastes was compared. Pseudomonas aeruginosa and Serratia ficaria mixed culture consumed the wastes better than the single bacterial cultures. The highest log. number of viable cells in mixed culture was 6.842 , while in single bacterial cultures it was 6.683 and 5.631, respectively. after 3 days in API medium containing the refinery wastes. The effect of some environmental conditions on the degradation of petroleum wastes was studied included aeration , NaCl concentration , pH and temperature. The growth of bacteria in the agitated culture was higher than stagnant culture the log. of cell no. was 6.021 in the first culture. The h
... Show MoreThe current study aims to show the importance of plant products as mosquitocides against Culex quinquefasciatus. Castor oil Nanoemulsions were subedit in various ratios including castor oil, ethanol, tween 80, and deionized water by using ultrasonication. Thermodynamic, centrifugation, PH, assay which improved that the formula of 10 ml of castor oil, ethanol 5ml, tween 80 (14 ml) and deionized water 71ml was more stable than other formulas. The stable formula of castor oil nanoemulsion was characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS). Nanoemulsion droplets were spherical in shape and were found to have a Z-average diameter of 87.4nm. A concentration of ca
... Show MoreTillage tools are subject to friction and low-stress abrasive wear processes with the potential deterioration of the desired soil quality, loss of mechanical weed efficacy, and downtime for replacing worn tools. Limited experimental methods exist to quantify investigate the effect of wear-resistant coatings on shape parameters of soil-engaging tools. ASTM standard sand/rubber wheel abrasion and pin-on-disk tests are not able to simulate wear characteristics of the complex shape of the tillage tools. Even though the tribology of tillage tools can be realistic from field tests, tillage wear tests under field conditions are expensive and often challenging to generate repeatable engineeri
This paper deals with the preparation of new monomers and polymers which including heterocyclic unit. The diacid chlorides compounds [1-3] were prepared from the reaction of glutaric acid, adipic acid, terephthalic acid with thionyl chloride. Succinic acid reacted with ethanol to produce compound [4]. Compound [4] reacted with hydrazine hydrate to obtain succinic hydrazide [5].Compound [5] reaction with CS2 and KOH in absolute ethanol to produce compound [6].The polymers [7-12] have been created by reacting diacid chlorides compounds [1-3] with compound[5] or [6] in dry pyridine with some drops of DMF. The topology of produced compounds has characterized through their spectral and analytical data as in FT-IR spectra, Thermal analysis [DSC,
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