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Effect of Oscillatory Motion in Enhancing the Natural Convection Heat Transfer from a Vertical Channel
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This paper reports an experimental study regarding the influence of vertical oscillations on the natural convection heat transfer from a vertical channel. An experimental set-up was constructed and calibrated; the vertical channel was tested in atmosphere at 25o
C. The channel-to-ambient temperature difference was varied with the power supply to the electrical heater ranging between
15W to 70W divided into five levels. Data sets were measured under different operating condition from a test rig under six vibrating velocities (VVs) levels ranging from (5-30 m/s) in addition to the stationary state. The results show that the maximum heat transfer enhancement factor (E) occurs at Rayleigh number (Ra=2.328×103 ) and vibrational Reynolds number ( Rev=6.365×103 ); this
enhancement reached to (7.685%).The results also illustrated that the temperature gradient along the channel wall length was enhanced by inducing the oscillatory motion to the channel. Rayleigh and vibrational Reynolds numbers were ranging between (2.306×103 - 5.564×103) and (0.0 - 19.86×103) respectively. Finally, A correlation which summarized the effects of both Ra and Rev was
determined for the Nusselt numbers.

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Publication Date
Wed Sep 02 2015
Journal Name
Lap Lambert Academic Publishing
The role of tibialis posterior transfer in correction of foot drop
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Publication Date
Wed Jun 19 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Accounting information system and its role in enhancing competitivness in the public industrial sector companies in iraq, from the standpoint of the auditors at the federal supeme audit board field study
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In a world of fierce competition companies of different activities strive to strengthen their competitiveness in order to be able to deliver greater value to their customers and gain a distinct sites in competition with other companies in the market at the local and international levels. Every company seeks to focus on one or more of the competitive capabilities in order to turn it into an obvious advantage or a number of competitive advantages to contribute in improving the performance and superiority over its competitors. Therefore, the management of companies no longer need only useful information for the internal aspects of the environment, but also need to include the external environment that includes various and constantly changin

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Publication Date
Fri Dec 25 2009
Journal Name
Wireless Personal Communications
A N-Radon Based OFDM Trasceivers Design and Performance Simulation Over Different Channel Models
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In this paper a new method is proposed to perform the N-Radon orthogonal frequency division multiplexing (OFDM), which are equivalent to 4-quadrature amplitude modulation (QAM), 16-QAM, 64-QAM, 256-QAM, ... etc. in spectral efficiency. This non conventional method is proposed in order to reduce the constellation energy and increase spectral efficiency. The proposed method gives a significant improvement in Bit Error Rate performance, and keeps bandwidth efficiency and spectrum shape as good as conventional Fast Fourier Transform based OFDM. The new structure was tested and compared with conventional OFDM for Additive White Gaussian Noise, flat, and multi-path selective fading channels. Simulation tests were generated for different channels

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Publication Date
Thu May 18 2023
Journal Name
Journal Of Engineering
Experimental Study of Power Increase Transient in Heat Generation Systems Simulated By Immersed Heat Source
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Theoretical and experimental investigations of the transient heat transfer parameters of constant heat flux source subjected to water flowing in the downward direction in closed channel are conducted. The power increase transient is ensured by step change increase in the heat source power. The theoretical investigation involved a mathematical modeling for axially symmetric, simultaneously developing laminar water flow in a vertical annulus. The mathematical model is based on one dimensional downward flow. The boundary conditions of the studied case are based on adiabatic outer wall, while the inner wall is subjected to a constant heat flux. The heat & mass balance equation derived for specified element of bulk water within the annulu

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Publication Date
Tue Apr 01 2014
Journal Name
International Communications In Heat And Mass Transfer
Determination of a time-dependent thermal diffusivity and free boundary in heat conduction
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Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Adsorption of Levofloxacine Antibacterial from Contaminated Water by Non – Conventional Low Cost Natural Waste Materials
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An experimental study was conducted with low cost natural waste adsorbent materials, barley husks and eggshells, for the removal of Levofloxacine (LEVX) antibacterial from synthetic waste water. Batch sorption tests were conducted to study their isothermal adsorption capacity and compared with conventional activated carbon which were, activated carbon > barley husks > eggshells with removal efficiencies 74, 71 and 42 % with adsorbents doses of 5, 5 and 50 g/L of activated carbon, barley husks, and eggshells respectively. The equilibrium sorption isotherms had been analyzed by Langmuir, Freundlich, and Sips models, and their parameters were evaluated. The experimental data were correlated well with the Langmuir model which gives the

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Publication Date
Mon Jun 17 2019
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Dynamic Channel Assignment Using Neural Networks
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This paper presents a proposed neural network algorithm to solve the shortest path problem (SPP) for communication routing. The solution extends the traditional recurrent Hopfield architecture introducing the optimal routing for any request by choosing single and multi link path node-to-node traffic to minimize the loss. This suggested neural network algorithm implemented by using 20-nodes network example. The result shows that a clear convergence can be achieved by 95% valid convergence (about 361 optimal routes from 380-pairs). Additionally computation performance is also mentioned at the expense of slightly worse results.

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Publication Date
Thu May 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Channel Estimation and Prediction Based Adaptive Wireless Communication Systems
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Wireless channels are typically much more noisy than wired links and subjected to fading due to multipath  propagation which result in ISI and hence high error rate. Adaptive modulation is a powerful technique to improve the tradeoff between spectral efficiency and Bit Error Rate (BER). In order to adjust the transmission rate, channel state information (CSI) is required at the transmitter side.

In this paper the performance enhancement of using linear prediction along with channel estimation to track the channel variations and adaptive modulation were examined. The simulation results shows that the channel estimation is sufficient for low Doppler frequency shifts (<30 Hz), while channel prediction is much more suited at

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Publication Date
Sun Jan 08 2023
Journal Name
Journal Of Planner And Development
Social sustainability in vertical housing complexes/study area: Al Salam Haiy
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Living in sustainable residential place is one of the most important factors affecting the quality of life in neighborhood complex within the vertical housing complexes. This research focuses on indicators of social sustainability because of their effective impact in achieving a good quality of life . The most prominent of these indicators include: (social interaction, neighborhood grouped and trust, social cohesion, security and safety, privacy, connectivity opportunities for meeting and , and community participation, and cultural diversity). This was done through a questionnaire (for the residents of the Al-Salam residential complex in the city of Baghdad), and the form includes a set of questions related to indicators of social sustai

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Publication Date
Sun Nov 25 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Study of the natural radioactivity of selected samples of the soil of Al-Nada district in Najaf
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   This study reported activity concentration of 238 U, 232 Th, 40 K in 50 soil samples AL-Nada district - Najaf Governorate - Iraq Measurement using gamma ray spectrometer NaI (TI) (3x3). The activity concentrations of natural radionuclides are found to range from (31.319  Bq.Kg-1 to (1.1583 ± 0.0821) Bq.Kg-1with average (11.851 0.281) Bq.Kg-1 of uranium 238U.  From (1.117±0.048)  Bq.Kg-1 to  (23.948 ) Bq.Kg-1  with an  average of  (6.283 0.148 ( Bq.Kg-1 for thorium 232Th,.from(13.592±0.282) Bq.Kg-1 to (705.834 6.179) Bq.Kg-1 and average (265.494 1.445) Bq.Kg-1 potassium40K , equivalent radium  from (12.489 0.328) Bq.Kg-1 to (84.199 1.911) Bq.Kg-

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