There have been many advances in the solar chimney power plant since 1930 and the first pilot work was built in Spain (Manzanares) that produced 50 KW. The solar chimney power plant is considered of a clean power generation that needs to be investigated to enhance the performance by studying the effect of changing the area of passage of air to enhance the velocity towards the chimney to maximize design velocity. In this experimental and numerical study, the reduction area of solar collector was investigated. The reduction area that mean changing the height of glass cover from the absorbing plate (h1=3.8cm, h2=2.6cm and h3=1.28cm). The numerical study was performed using ANSYS Fluent software package (version 14.0) to solve governing equations. The aim of this work was to study the effect of change the height of reduction area to the design velocity (velocity move the blade of turbine at inlet in the chimney). The results showed that the third height (h3=1.28cm) gives the best result because when decreasing the height between the glass cover and absorbing plate, the area between them decreased and the design velocity increased then the efficiency of solar chimney model was increased.
This research aimed at studying the role of calculated knowledge an its efficiency in improving the performance especially most of the organizations are living within knowledge era which concentrate on new technology investment in different fields of modern live . Under the scientific trends towards the economy of calculated knowledge which depend basically on new computer program in order to utilize the knowledge to raise the level of work performance exploiting different resources in the best way that helps the organizations to achieve their objectives because the information technology and computer programs became a means of survival and indispensible instrument within the developed world which depend on prosperity . progress
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The research aims to study the role of e-government in enhancing institutional performance. The dimensions of e-government are: (support and commitment of senior management, technical structures, organization and human resources, knowledge and information, work procedures, attention to citizens' satisfaction, and client parties),while the dimensions of institutional performance are: (Service improvement, innovation, efficiency and effectiveness).
The research used electronic questionnaire as a main tool for data collection, The questionnaire included all the employees in the e-government project in Department of Government Coordinate and Citizen Affairs at the General Secretariat of the C
... Show MoreThis research estimates the effect of independent factors like filler (3%, 6%, 9%, 11% weight fraction), normal load (5N, 10N, 15N), and time sliding (5,7 , 9 minutes) on wear behavior of unsaturated polyester resin reinforced with jute fiber and waste eggshell and, rice husk powder composites by utilizing a statistical approach. The specimens polymeric composite prepared from resin unsaturated polyester filled with (4% weight fraction) jute fiber, and (3%, 6%, 9%, 11% weight fraction) eggshell, and rice husk by utilizing (hand lay-up) molding. Dry sliding wear experiments were carried utilizing a standard (pin on disc test setup) following a well designed empirical schedule that depends on Taguchi’s experimental design L9 (MINIT
... Show MoreThe rate of gas induction was measured in gas-inducing type mechanically agitated contactors provided with two impellers. A reactor of 0.5 m i.d. was used with a working capacity of 60 liters of liquid. Tap water was used as the liquid phase, and air was used as the gas phase. The bioreactor mixing system consists of two equal diameter stirrers; the top impeller is shrouded-disk/curved-blade turbine with six evacuated bending blades, while the bottom impeller was disk turbine. The impeller speed was varied in the range of 50 to 800 rpm. The ratio of impeller diameter to tank diameter (D/T) and the submergence (S) of upper impeller from the top were varied. The effects of clearance of lower impeller from the tank bottom (C2) an
... Show MoreIn this study, industrial fiber and polymer mixtures were used for high-speed impact (ballistic) applications where the effects of polymer (epoxy), polymeric
mixture (epoxy + unsaturated polyester), synthetic rubber (polyurethane), Kevlar fiber, polyethylene fiber (ultra High molecular weight) and carbon fiber.
Four successive systems of samples were prepared. the first system component made of (epoxy and 2% graphene and 20 layer of fiber), then ballistic test was
applied, the sample was successful in the test from a distance of 7 m. or more than, by using a pistol personally Glock, Caliber of 9 * 19 mm. The second
system was consisting of (epoxy, 2% graphene, 36 layers of fiber and one layer of hard rubber), it was succeeded
Optimized Link State Routing Protocol (OLSR) is an efficient routing protocol used for various Ad hoc networks. OLSR employs the Multipoint Relay (MPR) technique to reduce network overhead traffic. A mobility model's main goal is to realistically simulate the movement behaviors of actual users. However, the high mobility and mobility model is the major design issues for an efficient and effective routing protocol for real Mobile Ad hoc Networks (MANETs). Therefore, this paper aims to analyze the performance of the OLSR protocol concerning various random and group mobility models. Two simulation scenarios were conducted over four mobility models, specifically the Random Waypoint model (RWP), Random Direction model (RD), Nomadic Co
... Show MoreAccording to the circumstances experienced by our country which led to Occurrence of many crises that are the most important crisis is gaining fuel therefore , the theory of queue ( waiting line ) had been used to solve this crisis and as the relevance of this issue indirect and essential role in daily life .
This research aims to conduct a study of the distribution of gasoline station in (both sides AL – kharkh and AL Rusafa, for the purpose of reducing wasting time and services time through the criteria of the theory of queues and work to improve the efficiency of these stations by the other hand. we are working to reduce the cost of station and increase profits by reducing the active serv
... Show MoreBackground: Masseter muscle is one of the most obvious muscles of mastication and considered as one indicator of jaw muscle activity. It has a major influence on the transverse growth of the midface and the vertical growth of the mandible. This study undertaken to determine the role of cephalometric analysis for discrimination between Cl I and Cl III skeletal relationships, determine the role of ultrasonography in determination of masseter muscle thickness, compare masseter muscle thickness between Cl I and Cl III skeletal relationships, and determine the effect of gender on masseter muscle thickness. Material and Method: The sample of the current study consisted of 70 Iraqi subjects 40 males and 30 females with age ranging 18-25 years. The
... Show MoreThe investment budget represents a stage of the investment decision in service units, and the preparation and implementation needs to be a complement of the same planning part, because the planning does not end with the development of the plan, but includes a follow-up implementation, so it has to be effective and efficient oversight of the estimates and procedures for disbursement of funds approved for investment projects, The problem with research in that local governments suffer from the presence of Allkaat and problems facing the implementation of the investment budget projects due to the adoption budget items which can not be measured the efficiency of the performance of these units of government by, and shortcomings in the control
... Show MorePraise be to God who created the soul, perfected it, and inspired it with its immorality and piety. He says in His Noble Book: ﭤ Fajr: 27-30 Glory be to You, O God! O Lord, on whom I have chosen for You as a beloved from myself and the soul of the two worlds, may our master Muhammad be sacrificed for him, who enlightened the horizons with his introduction to enlightenment. It soon ends with the end of pleasure, which is the opposite of the pleasure of thought and meaning, as it is permanent and continuous, and from here we see that the Messenger of God, may God’s prayers and peace be upon him, urges us in various places to seek knowledge and fortify the soul and thought in a way that raises one’s status and protects him from the st
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