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A Laboratory Study Attempt of Flow and Energy Dissipation in Stepped Spillways
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A new laboratory study conducted on stepped spillways in order to investigate their efficiency of dissipating flow energy. All previous study on stepped spillway indicated that the flow energy dissipation decreased as increasing in discharge. Increasing in the step numbers and the spillway slope led to energy dissipation decrease. In this study, an experimental attempt to increase energy dissipation at variable discharges was performed on stepped spillway and that leads to decreasing the cost of initiating the stilling basin or may be ignoring it. Five spillways were constructed from concrete and tested to investigate and compare among them. Three were roughed by gravel with different size for each one, one of them was stepped without any addition, and the last one was stepped with cavitation. The height of stepped spillways was 18 cm with unique numbers of steps (n = 3), and unique downstream slope of stepped face (θ =30⁰) were utilized. The percentage of relative energy dissipation (R.E.D) was increased using rough surface with coarse gravel. When the size of gravel increased, the R.E.D was increased and when using the ratio between heights of gravel to steps of 0.5, the R.E.D was increased to about triple compared with traditional spillways. The R.E.D was decreased when the cavitation on the stepped surface was utilized compared to the stepped spillway without any addition for large discharges and that was inverse for small discharges. Comparing to steps without any addition, the rouged steps with the larger size of gravel maximized the energy dissipation for both small and large discharges. The relative energy dissipation was 26.73 % compared with traditional spillway and 16.73 % compared with stepped spillway without any addition, since the stepped spillways more effective than traditional spillways by 10 %. In general, the R.E.D was decreased when increasing the discharge.

 

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Publication Date
Mon Dec 31 2018
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
BIOLOGICAL ASPECTS AND PREDATORY EFFICIENY OF PREDATOR Chilocorus bipustulatus (L.) COLEOPTERA :COCCINELLIDAE ON DATE PALM SCALE Parlatoria blanchardi (T.) DIASPIDIDAE: HOMOPTERA UNDER LABORATORY CONDITIONS.: BIOLOGICAL ASPECTS AND PREDATORY EFFICIENY OF PREDATOR Chilocorus bipustulatus (L.) COLEOPTERA :COCCINELLIDAE ON DATE PALM SCALE Parlatoria blanchardi (T.) DIASPIDIDAE: HOMOPTERA UNDER LABORATORY CONDITIONS.
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Laboratory studies were conducted at the biological control unit, college of Agriculture, University of Baghdad to evaluate some biological aspects of the predator Chilocorus bipustulatus (Coleoptera: Coccinellidae), which is considered one of the most important predators on many insect pests, especially the scale insect, Parlatoria blanchardi, (Homoptera: Diaspididae) on date palms. The results showed that biological parameters of the predator were varied according to different degree of temperature. Egg incubation period was significantly different and reached to 7.5 and 5.44 day at 25 and 30°C respectively, Fertility was the same 100% at both temperature degrees. Larval growth periods were 17.41 and 16.12 day as well as the mortality

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Publication Date
Wed Dec 11 2019
Journal Name
Journal Of The College Of Education For Women
Terrorism and Internal Displacement in Iraq: A Field Study in Baghdad
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    Terrorism is a serious problem for many societies today. This research aims to identify the impact of terrorism and displacement crisis on human security, which was a shock to the Iraqi society in terms of its impact on the psychological, social and economic conditions of the individual, family, and society. The variety of methods of carrying out the terrorist operations that resulted from the phenomenon of human displacement witnessed by Iraq since the middle of 2014. This phenomenon has its demographic, political and social dimensions.

    In order to achieve the goal of this study and the importance of the subject, the social survey method was used by selecting a sample of 200 IDPs in a compou

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Publication Date
Fri Mar 20 2020
Journal Name
Journal Of Xi'an University Of Architecture & Technology
Academic Laboratory Skills For Chemistry Students at the College of Education For Pure Sciences -Ibn Al Haitham
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The current research aims to find out the extent to which students of the Faculty of Education for Pure Sciences\/Ibn al-Haitham have owned laboratory academic skills, the researcher adopted a descriptive research approach to conform to the goal of the research, the research sample the consisted of 140 students from the Department of Chemistry Phase II, The research tool, which consisted of a measure of laboratory academic skills, which consisted of seven skills and consisted of 28 paragraphs (four paragraphs per field), was prepared and the pent-up scale was chosen because the selected sample were university students, and the results showed the ownership of students' skills of laboratory academic skills other than skill The use of the libr

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Publication Date
Fri Dec 15 2023
Journal Name
Bionatura Journal. Ibero-american Journal Of Biotechnology And Life Sciences
Efficacy of the entomopathogenic fungus, Metarhizium anisoplae, against Khapra beetle Trogoderma granarium (Coleoptera: Dermestidae) under laboratory conditions
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Publication Date
Sat Dec 02 2023
Journal Name
Journal Of Engineering
Performance Assessment of Pile Models Chemically Grouted by Low-Pressure Injection Laboratory Device for Improving Loose Sand
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The complexity and partially defined nature of jet grouting make it hard to predict the performance of grouted piles. So the trials of cement injection at a location with similar soil properties as the erecting site are necessary to assess the performance of the grouted piles. Nevertheless, instead of executing trial-injected piles at the pilot site, which wastes money, time, and effort, the laboratory cement injection devices are essential alternatives for evaluating soil injection ability. This study assesses the performance of a low-pressure laboratory grouting device by improving loose sandy soil injected using binders formed of Silica Fume (SF) as a chemical admixture (10% of Ordinary Portland Cement OPC mass) to di

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Publication Date
Sat Dec 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Risk measurement and its role in preparing the target cash flow statement and rationalizing administrative decisions
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Abstract :

The Aims of this research is to describe the concept of risk, its type and method of measurement, and to clarify the impact of these risks on the expected cash flow statement and the preparation of the target cash flow statement that takes these risks into consideration. Because the local economic environment is exposed to many risks, Therefore, this list will be predictive, which will help the economic unit to make administrative decisions, especially decisions related to operational, investment and financing activities. Therefore, the research problem is based on the fact that most of the local economic units are the list of flows According to the actual basis and not according to the discretionary basis (bud

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Publication Date
Sun Mar 01 2009
Journal Name
Baghdad Science Journal
Determination of Similarity and Variance in Energy and Depositional Environment, the Difference in Diagenesis and the Variance in the Petrophysical Properties of Reservoir Rocks in Zubair Formation , South Iraq
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Records of two regionalized variables were processed for each of porosity and permeability of reservoir rocks in Zubair Formation (Zb-109) south Iraq as an indication of the most important reservoir property which is the homogeneity , considering their important results in criterion most needed for primary and enhanced oil reservoir .Z and F tests that were calculated for the two above mentioned properties of pair units of Zubair Formation have shown the difference in depositional energy and different diagenesis between units IL and AB , DJ and AB , and the similarity in grains size , sorting degree , depositional environment and pressure gradients between IL and AB units , LS and IL units ; also the difference in the properties above betw

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Publication Date
Sat Dec 01 2018
Journal Name
Indonesian Journal Of Electrical Engineering And Computer Science
An Energy-Aware and Load-balancing Routing scheme for Wireless Sensor Networks
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<p>Energy and memory limitations are considerable constraints of sensor nodes in wireless sensor networks (WSNs). The limited energy supplied to network nodes causes WSNs to face crucial functional limitations. Therefore, the problem of limited energy resource on sensor nodes can only be addressed by using them efficiently. In this research work, an energy-balancing routing scheme for in-network data aggregation is presented. This scheme is referred to as Energy-aware and load-Balancing Routing scheme for Data Aggregation (hereinafter referred to as EBR-DA). The EBRDA aims to provide an energy efficient multiple-hop routing to the destination on the basis of the quality of the links between the source and destination. In

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Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
An Investigation into Thermal Performance of Mist Water System and The Related Consumption Energy
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Experimental tests were conducted to investigate the thermal performance (cooling effect) of water mist system consisting of 5μm volume median diameter droplets in reducing the heat gain entering a room through the roof and the west wall by reducing the outside surface temperature due to the evaporative cooling effect during the hot dry summer of Baghdad/Iraq. The test period
was Fifty one days during the months May, June, and July 2012. The single test day consists of 16 test hours starting from 8:00 am to 12:00 pm. The results showed a reduction range of 1.71 to 15.5℃ of the roof outside surface temperature and 21.3 to 76.6% reduction in the daily heat flux entering the room through the roof compared with the case of not using w

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Publication Date
Thu Feb 01 2024
Journal Name
Journal Of Engineering
Performance Evaluation of Two Stages Parallel Flow Indirect Evaporative Cooling with Aspen Pads in Baghdad Climate Conditions
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This study delves into the realm of advanced cooling techniques by examining the performance of a two-stage parallel flow indirect evaporative cooling system enhanced with aspen pads in the challenging climate of Baghdad. The objective was to achieve average air dry bulb temperatures (43 oC) below the ambient wet bulb temperatures (24.95 oC) with an average relative humidity of 23%, aiming for unparalleled cooling efficiency. The research experiment was carried out in the urban environment of Baghdad, characterized by high temperature conditions. The investigation focused on the potential of the two-stage parallel flow setup, combined with the cooling capability of aspen pads, to surpass the limitat

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