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ω-Perfect Mappings
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In this paper, we shall introduce a new kind of Perfect (or proper) Mappings, namely ω-Perfect Mappings, which are strictly weaker than perfect mappings. And the following are the main results: (a) Let f : X→Y be ω-perfect mapping of a space X onto a space Y, then X is compact (Lindeloff), if Y is so. (b) Let f : X→Y be ω-perfect mapping of a regular space X onto a space Y. then X is paracompact (strongly paracompact), if Y is so paracompact (strongly paracompact). (c) Let X be a compact space and Y be a p*-space then the projection p : X×Y→Y is a ω-perfect mapping. Hence, X×Y is compact (paracompact, strongly paracompact) if and only if Y is so.

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Engineering
THEORETICAL AND EXPERIMENTAL STUDY ON THERMAL PERFORMANCE OF CLOSED WET COOLING TOWER
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Thermal performance of closed wet cooling tower has been investigated experimentally and theoretically
in this work. The theoretical model based on heat and mass transfer equations and heat and mass transfer balance equations which are established for steady state case. A new small indirect cooling tower was used for conducting experiments. The cooling capacity of cooling tower is 1 kW for an inlet water temperature of 38oC, a water mass velocity 2.3 kg/m2.s and an air wet bulb temperature of 26oC. This study investigates the relationship between saturation efficiency, cooling capacity and coefficient of performance of closed wet cooling tower versus different operating parameters such wet-bulb temperature, variable air-spray water fl

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Publication Date
Tue Mar 30 2021
Journal Name
College Of Islamic Sciences
Need and transgression in Surat (Abs) Semantic grammatical study: Need and transgression in Surat (Abs)
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      The research aims to highlight the significance and composition and the diversity of meanings and the Quranic context in the necessary and transgressive verbs in Surat (Abs).

      This research consists of : a preamble , and two studies . The researcher addressed in the preliminary the importance of the phenomenon of necessity and infringement, the signs of the necessary action , the structure and controls of the act , the methods of infringement , its sections and signs.

      As for the first topic : The researcher addressed the necessary verbs in Surat Abs , an applied study in terms of grammati

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Publication Date
Tue Apr 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Financial markets liquidity and their impact in the return of common stocks
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    The research aimed to study the financial markets liquidity and returns of common stocks , Take the research  the theoretical concepts  associated with each of the liquidity of financial markets and returns of common stocks , As well as the use of mathematical methods in the practical side to measure market liquidity and Stocks  Return, the community of research in listed companies in Iraqi stock exchange that have been trading on its stock and number 85 joint-stock company, The research was based to one premise, there is a statistically significant effect for the liquidity of the Iraqi stock exchange on returns  of common stocks  to traded companies in which , Using th

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