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Testing the performance of a solar energy cooling system in Baghdad city
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Renewable energy resources have become a promissory alternative to overcome the problems related to atmospheric pollution and limited sources of fossil fuel energy. The technologies in the field of renewable energy are used also to improve the ventilation and cooling in buildings by using the solar chimney and heat exchanger. This study addresses the design, construction and testing of a cooling system by using the above two techniques. The aim was to study the effects of weather conditions on the efficiency of this system which was installed in Baghdad for April and May 2020. The common weather in these months is hot in Baghdad. The test room of the design which has a size of 1 m3 was situated to face the geographical south. The test room is thermally insulated and connected to a solar chimney which generates a convection current to draw the air out of the room through a heat exchanger. The heat exchanger was submerged in a water tank of 2 m length, 1 m width and 1 m height. It was also covered with a layer of soil mixture with a thickness of 10 cm. The experiment simulates the natural conditions of a shallow water surface, connected to the room from the other side. The study results revealed that the air temperature inside the test room was lower than that of the ambient air outside. Pearson correlation coefficient showed that there was a strong direct relationship between solar radiation, temperature and wind speed from one side and the cooling efficiency from the other side. Also, there was a negative correlation between relative humidity and cooling efficiency.

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Publication Date
Sat Jun 01 2013
Journal Name
Engineering And Technology Journal
Performance Improvement of Multi-UserMC-CDMA system Using Discrete Hartly Transform Mapper
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Future wireless communication systems must be able to accommodate a large number of users and simultaneously to provide the high data rates at the required quality of service. In this paper a method is proposed to perform the N-Discrete Hartley Transform (N-DHT) mapper, which are equivalent to 4-Quadrature Amplitude Modulation (QAM), 16-QAM, 64-QAM, 256-QAM, … etc. in spectral efficiency. The N-DHT mapper is chosen in the Multi Carrier Code Division Multiple Access (MC-CDMA) structure to serve as a data mapper instead of the conventional data mapping techniques like QPSK and QAM schemes. The proposed system is simulated using MATLAB and compared with conventional MC-CDMA for Additive White Gaussian Noise, flat, and multi-path selective fa

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Publication Date
Thu Dec 01 2022
Journal Name
Al-khwarizmi Engineering Journal
BER Performance Improvement of Dual Chaotic Maps Based on STBC Communication System
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Sensitive information of any multimedia must be encrypted before transmission. The dual chaotic algorithm is a good option to encrypt sensitive information by using different parameters and different initial conditions for two chaotic maps. A dual chaotic framework creates a complex chaotic trajectory to prevent the illegal use of information from eavesdroppers. Limited precisions of a single chaotic map cause a degradation in the dynamical behavior of the communication system. To overcome this degradation issue in, a novel form of dual chaos map algorithm is analyzed. To maintain the stability of the dynamical system, the Lyapunov Exponent (LE) is determined for the single and dual maps. In this paper, the LE of the single and dual maps

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Publication Date
Mon May 09 2016
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
Choosing the Planning Aggregate Production strategy of the Organization of service - A Case Study in Baghdad hotel: Choosing the Planning Aggregate Production strategy of the Organization of service - A Case Study in Baghdad hotel
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Constitute a planning problem on the basis of personal experience and self-governance in the service organizations away from quantitative scientific method in planning an anchor and a platform, who made a recent research study, analysis and interpretation through scientific methodology adopted which formed its contents, The research aims to identify the true reality of production planning in service organizations, specifically in the Baghdad Hotel as a society to look, in order to assess the best strategy through the standard cost of the strategies of tracking and settlement to cope with developments on services demand changes, Search results confirmed that the settlement rates of production strategy is the best strategy in accordance wi

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Publication Date
Sat Feb 27 2021
Journal Name
Journal Of Engineering
Using Geographic Information Systems (GIS) Program and Water Quality Index (WQI) to Assess and Manage Groundwater Quality in the City of Baghdad
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Groundwater is an essential source because of its high quality and continuous availability characterize this water resource. Therefore, the study of groundwater has required more attention. The present study aims to assess and manage groundwater quality's suitability for various purposes through the Geographical Information System GIS and the Water Quality Index WQI. The study area is located in the city of Baghdad in central Iraq, with an approximate area of ​​900 , data were collected from the relevant official departments representing the locations of 97 wells of groundwater in the study area for the year 2019, as it included physicochemical parameters such as  pH, EC, TDS, Na, K, Mg, Ca, Cl,  , and &nbs

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Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
(Energy alternatives and the possibility of substitution)
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Many of the signs that the global energy system indicate the start of a period of transition from total dependence on fossil energy sources, especially oil, into a new era in which alternative energy sources play an important role in meeting the growing needs of energy demand, so sought many of the developed countries through research the studies carried out to try to bring renewable energy sources and non-renewable (shale oil, oil sands, solar energy, wind energy .... etc) replace traditional fossil energy sources (oil, gas, coal) and despite the recent availability dramatically and spread throughout the the world, but they are going to dry up in the foreseeable future. So many countries, especially the developed sought to find

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Publication Date
Thu Apr 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
The Role of the values of accounting culture in maximizing financial performance - A field study in a sample of Iraqi banks
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The influence of culture on accounting systems and practices, including financial reports and accounting information through the values ​​identified by Gray and derived from social-cultural values, and the four accounting values ​​were derived from generally accepted accounting principles represented by (Conservatism, Uniformity, Secrecy, and Professionalism). Important and significant in maximizing financial performance, and measuring the extent of the role of these values ​​in improving financial performance through attention to the values ​​of accounting culture, this research

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Publication Date
Fri Mar 15 2019
Journal Name
Al-khwarizmi Engineering Journal
Experimental and Theoretical Study of the Energy Flow of a Two Stages Four Generators Adsorption Chiller
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This work is concerned with a two stages four beds adsorption chiller utilizing activated carbon-methanol adsorption pair that operates on six separated processes. The four beds that act as thermal compressors are powered by a low grade thermal energy in the form of hot water at a temperature range of 65 to 83 °C.  As well as, the water pumps and control cycle consume insignificant electrical power. This adsorption chiller consists of three water cycles. The first water cycle is the driven hot water cycle. The second cycle is the cold water cycle to cool the carbon, which adsorbs the methanol. Finally, the chilled water cycle that is used to overcome the building load. The theoretical results showed that average cycle cooling power

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Publication Date
Sun Jun 01 2008
Journal Name
Baghdad Science Journal
The role of annealing temperature on the optical energy gap and Urbach energy of Se:2%Sb thin films
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The optical energy gap(Eopt) and the width of the tails of localized states in the band gap (?E) for Se:2%Sb thin films prepared by thermal co-evaporation method as a function of annealing temperature are studied in the photon energy range ( 1 to 5.4)eV.Se2%Sb film was found to be indirect transition with energy gap of (1.973,2.077, 2.096, 2.17) eV at annealing temperature (295,370,445,520)K respectively. The Eopt and ?E of Se:2%Sb films as a function of annealing temperature showed an increase in Eopt and a decrease in ?E with increasing the annealing temperature. This behavior may be related to structural defects and dangling bonds.

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Publication Date
Thu Nov 01 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Testing Bromocriptine Dose Necessary For Suppression of Lactation in Rats: Morphological Study
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Abstract: Objectives: The lowest dose of bromocriptine, necessary for suppression of lactation in rats, was estimated in this investigation. Methodology: Fifty healthy lactating rats were treated with different doses of bromocriptine. Cessation of lactation was assessed clinically and histologically. Results: Revealed that the lowest dose capable of lactation suppression is 4 mg bromocriptine / kg body wt. / day. It is very important to know the exact dose, which can suppress lactation in rats because these laboratory animals are commonly employed in experiments concerning this topic. Key words: Bromoci

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Publication Date
Thu Jun 30 2022
Journal Name
Muthanna Journal For Agricultural Sciences
Developing and testing of automated sprayer for agrochemicals application trials in Iraq
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The field experiment was conducted with the aim of developing and testing an automatic sprayer for agricultural spray experiments and studying the effect of spray pressure, spray speed and spray height on the spraying process. The effects of the major spraying factors (pressure, speed, and height) on the spraying performance of the automatic sprayer were studied. This study included several traits: First - the drop sizes - Second - the penetration of the spray into the vegetation cover - Third, the spray wasted. The results showed: - First: - Increase in coverage percentage when using the first speed, 2 km / h, which amounted to 26.85%. An increment in the spraying penetration of the vegetation cover was observed at the second speed

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