All domains in this world built based on set of theories. Those theories have been responsible for interpretation of some phenomena and interlocking relationships around us. Commonly, theories are categorized by which aspect is believed. Also,can find a group of theories produced regardingto the leadership domain. This paper will be presented some of these theories like (Great Man Theory, Trait Theory, Behavioral Theories, Contingency Theories, Situational Theory, Transactional Theories, and Transformational Theories). where these theories considered the most popular and common in the field of leader and will be discussed by this work
Abstract
In this research, the morphology and mechanical properties of (Epoxy/PVC) blend were investigated. (EP/PVC) blend was prepared by manual mixing of epoxy resin with different weight ratios of (Poly vinyl chloride (PVC) after dissolving it in cyclohexanon). Five sheets of polymer blends in wt% included (0%, 5%, 10%, 15% and 20%) of PVC were prepared at room temperature. Tests were carried out to study some mechanical properties for these blends and compared with the properties of pure epoxy. The morphology of the prepared materials was examined to study the compatibility nature between the two polymers under work. It was found that the best ratio of addition is (20%) of PVC.
... Show MoreWe introduce in this paper the concept of approximaitly semi-prime submodules of unitary left -module over a commutative ring with identity as a generalization of a prime submodules and semi-prime submodules, also generalization of quasi-prime submodules and approximaitly prime submodules. Various basic properties of an approximaitly semi-prime submodules are discussed, where a proper submodule of an -module is called an approximaitly semi-prime submodule of , if whenever , where , and , implies that . Furthermore the behaviors of approximaitly semi-prime submodule in some classes of modules are studied. On the other hand several characterizations of this concept are
... Show MoreOur aim in this paper is to study the relationships between min-cs modules and some other known generalizations of cs-modules such as ECS-modules, P-extending modules and n-extending modules. Also we introduce and study the relationships between direct sum of mic-cs modules and mc-injectivity.
The research discussed the propositions of functional structures and the requirements for their transformation according to the variables of use and human interaction through the variables of functions with one form products، multifunctional variables، and transforming form in one product. The patterns of user’s interaction with products were discussed through the variables of functional type، starting from defining the types of functions in the industrial product structures to: practical functions، which were classified into: informational functions، ergonomic functions، use، handling، comfort، global، anthropometric adaptation and physical postures. While the interaction variables were discussed according to the meaning fun
... Show MoreNowadays, the rapid development of multi-media technology and digital images transmission by the Internet leads the digital images to be exposed to several attacks in the transmission process. Therefore, protection of digital images become increasingly important.
To this end, an image encryption method that adopts Rivest Cipher (RC4) and Deoxyribonucleic Acid (DNA) encoding to increase the secrecy and randomness of the image without affecting its quality is proposed. The Means Square Error (MSE), Peak Signal-to-Noise Ratio (PSNR), Coefficient Correlation (CC) and histogram analysis are used as an evaluation metrics to evaluate the performance of the proposed method. The results indicate that the proposed method is secure ag
... Show MoreThis research includes the principles of the democracy، and to which extent it can contribute in establishing these principles. Democracy is not only to hold parliamentary or presidential elections but also the result of these elections wills it lead to the emergence of an integrated regime that can actually expresses the citizen's rights and to which extent those citizens can contribute in that regime and control it. Since 2005، when the first elections took place in Iraq after the US occupation of Iraq 2003، Iraqi people are looking to a rule that represented them and achieve their interests after getting rid of the totalitarian regimes and establishing an institutional regime that work by democratic means in order to achieve the so
... Show MoreNew series of Schiff bases 2(a-j) and corresponding beta-lactam derivatives 3(a-j) were synthesized from cefalexin (1) as starting material. The compound (1) was reacted with different aldehydes and ketones to give Schiff bases derivatives 2(a-j). The synthesized Schiff bases were cyclized by chloroacetyl chloride in the presence of triethylamine to form beta-lactam derivatives 3(a-j). The compounds were characterized by deremination melting point, FT-IR and 1H NMR. The beta-lactam derivatives were screened in vitro antibacterial against some bacterial species
Some esters were prepared from reaction of different molecular weight of PVA with some acid chloride (prepared by reaction of acid with thionyl chloride or phosphorous pentachloride)in the presence of pyridine. The thermal and reological properties were studied. The increasing Of bulky groups decreasing stability of the thermal and reological properties.
We report a method of converting non-conductive plastic surfaces into conductive by plating either copper electroless or copper electroplating -carbon black containing bending Agent onto Perspex plastics . Various approaches have been studied in order to comparing properties of the plated copper for two methods such as scanning electron microscopy (SEM),thickness, roughness, porosity, tensile Strength and elongation. The results show that the surface of electroplating was uniform, compact, and continuous and it had an obvious metallic sheen, while the surface of plated copper for electroless for it had many pores. Also observed that the coating was composed of small cells. Thes
... Show MoreTo determine the relationship between celiac disease and reproductive complication, twenty five women with clinically definite unexplained infertility aged (22-35) have been investigated and compared to fifteen apparently healthy women. All the studied groups were subjected to measurement of anti-tissue transglutaminase antibodies IgA and IgG by ELISA technique and anti-endomysial antibodies IgA and IgG by IFAT technique .There was a highly significant elevation (P< 0.01) in the concentration of anti- tTG IgA Abs compared to control group, Also, there was significant elevation (P< 0.05) in the concentration of anti- tTG IgG Abs compared to control group .The results illustrated that the prevalence of anti-EMA IgA and IgG Abs were (
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