The present work describes numerical and experimental investigation of the heat transfer characteristics in a plate-fin, having built-in piezoelectric actuator mounted on the base plate (substrate). The geometrical configuration considered in the present work is representative of a single element of the plate-fin and triple fins. Air is taken as the working fluid. A performance data for a single rectangular fin and triple fins are provided for different frequency levels (5, 30 and
50HZ) , different input power (5,10,20,30,40 and 50W) and different inlet velocity (0.5, 1, 2, 3, 4, 5 and 6m/s) for the single rectangular fin and triple fins with and without oscillation. The investigation was also performed with different geometrical fin heights ( 50mm and 35mm) and distance between the fins (3mm and 6mm). It is observed that the heat transfer increases with the increase in the frequency and Reynolds number. It is further observed that triple fins with (height=50mm and distance between the fins=3mm) gives better enhancement as compared to other
cases, The study shows that the piezoelectric actuator when mounted on the rectangular fins gives great promise for enhancing the heat transfer rate
The marketing logistic chain, as an integrated system aimed to balance the achievement of its main opposite objectives which represented in the access to the best service presented to the customer with lowest possible logistic costs especially the transportation costs, where encourages the researcher to choose the second objective as a field of this study in order to reduce the transportation costs in the final link of marketing logistic chain which related to delivering of fuel oil to the customer that falls within organizational responsibilities of the company under consideration (Oil Marketing Company) and also known in a brief name by (SOMO) through two methods, the first is by functioning quantative techniques by using trans
... Show MoreThe research dealt with the case stock repurchase policy of Emaar Real Estate Company one of listed companies in Dubai Stock exchange. The research has launched from the cognitive dimensions of repurchasing policy which took great concern in the literatures of financial management, and also this policy became as substitute for distributing the monitory profit in the last three decades in the international financial markets, but it did not get any importance in the Arab Markets such as that of the Arab Gulf in addition to the Iraqi Stock Exchange.
The research summarized a set of conclusions, the most important one was the consistence of analysis result with the test of the major two hypotheses (The first
... Show MoreMany isolated rural communities are located in regions where there is an abundant and reliable supply of solar energy, but where the distance to the nearest power station is many tens or even hundreds of kilometre. It is therefore mainly in these areas that rural electrification is now being provided by PV generators. since Stand-Alone PV generator can offer the most cost-effective and reliable option for providing power needed in remote places. Accordingly these isolated rural canters are fitted with PV for lighting, a refrigerator, a television and socket to supply kitchen appliances
Knowledge represents the foundation stone for the work of all organizations, are working who leads the thinking of individuals is the ability that leads to behavior based on rationality, it is the work that creates value to the organization and thus gain access to performance winning where that knowledge is a new type of capital based on the thought and experience and is the so-called intellectual capital, which is renewable and is constantly evolving. The study sought to explain the role of the climax knowledge in achieving the highest levels of performance Organizational and then access to the performance winning in educational organizations the study sample, was found to be a co
... Show MoreIn this paper thermo-hydrodynamic characteristics were investigated experimentally for a new type shell-helical coiled tube heat exchanger used as a storage tank of closed loop solar water heater system. Triple concentric helical coils were made of copper tubes of (12.5mm OD and 10mm ID) with coils diameter of (207, 152.2, 97mm) for outer, middle and inner coils respectively. The experiments were carried out during a clear sky days of (March and April 2012). The parameters studied in this work are: history of average temperature of shell side of the storage tank, collector heat gain, heat rejected from coils to shell side of the storage tank, collector efficiency, thermal effectiveness of the heat exchanger (storage tank), and pressure d
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Abstract
The miraculous of al-Quran has been surrounded by the attention of scholars, as it is the one that has astonished the rhetoricians with its eloquence. So , they paid attention to every part of it and hugely they studied it with accuracy in respect to its Surah ad Ayahs. It is considered the most important source from which Arab scholars and early grammarians drew, given their unanimity that it is the highest degree of eloquence and the best record of the common literary language.
Among these sciences is the science of Grammar, and without Qur’an, this science would not have emerged, which later had control over every science of Arabic
... Show MoreBackground: It is well known that mycotic antigens have an important
role in atopy and the induction of asthma. Now one of the important
subjects is the relation between respiratory bacterial and viral
infections in the inflammatory reactions accompanied with bronchial
asthma viruses Bacteria or their metabolites act as trigger for asthma
or increase it's intensity .
Objectives: To show the relation between asthma and some viral
infections serologically.
Methods: Direct ELISA test was employed to detect lgG specific for
Respiratory Syncytial virus (Rsv) parainfluenza virus type (p13) and
influenza virus in sera of (100) asthmatic patients of two age groups.
(10-17) and(18-50) years old. Serum samples from
Online examination is an integral and vital component of online learning. Student authentication is going to be widely seen when one of these major challenges within the online assessment. This study aims to investigate potential threats to student authentication in the online examinations. Adopting cheating in E-learning in a university of Iraq brings essential security issues for e-exam . In this document, these analysts suggested a model making use of a quantitative research style to confirm the suggested aspects and create this relationship between these. The major elements that might impact universities to adopt cheating electronics were declared as Educational methods, Organizational methods, Teaching methods, Technical meth
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Purpose: Providing practical knowledge of the requirements of a detailed feasibility study for selecting the investment project.
Findings: Directing the private sector towards investing in productive projects - the pre-cast reinforced concrete project - as it achieves a financial return as well as providing Providing foreign currencies by reducing imports and exploiting available natural resources
Practical implications: The importance of a detailed feasibility study to determining whether the project can be implemented or not.
The precast concrete method is one of the best modern c
... Show MoreThe current research deals with short term forecasting of demand on Blood material, and its' problem represented by increasing of forecast' errors in The National Center for Blood Transfusion because using inappropriate method of forecasting by Centers' management, represented with Naive Model. The importance of research represented by the great affect for forecasts accuracy on operational performance for health care organizations, and necessity of providing blood material with desired quantity and in suitable time. The literatures deal with subject of short term forecasting of demand with using the time series models in order to getting of accuracy results, because depending these models on data of last demand, that is being sta
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