Wasit Journal of Engineering Sciences

One of the major global issues today is energy consumption. Consequently, power management was introduced in various communication technologies. For IEEE 802.11wireless communication, thereis a Power Saving Mode scheme (PSM) for increase the battery life of cell phone. In this PSM,there are two key parameters: beacon period interval (BI) and listen interval(LI). In most work these values are chosen arbitrary. Here, a scheme to determine the optimal BI and LI for accomplishing the most astounding conceivable vitality proficiency is introduced. This is implemented with the application of a numerical sample to the standard IEEE 802.11 PSM and Access Point-PSM (AP-PSM) schemes. To ensure the quality of network performance analysis on the normal and change of parcel delays is doing. The well-known queuing (M/G/I) model with bulk services are utilized. After the implementation of the proposed analysis, “maximum rest plan time ratio optimal Sleep Scheme (OSS)” which is when participate stations stay in the doze mode it can be determined. Inthis research shows that the optimal BI and LI produce optimal OSS time ratio scheme also achieved optimal average and variance of packet delay.

This paper describes the rehabilitation and developing of an old didactic traditional elevator available in the laboratory. The authors tried to merge the programmable logic controller (PLC) with the elevator's traditional electric circuit for developing its control circuitry. ThePLC employed in this research is Simatic (s7-200), it was used to replace the old control system of the elevator which had high faults that were due to its complex wiring and numerous mechanical contacts which were able to burn out or could result in bad contacts. The obtained results were satisfactory because the merging procedure between the traditional and the modern systems is successfully implemented; personnel safety is improved and electromechanical problems were decreased .

The use of cutoffs underneath the hydraulic structures is considered a safe solution to ensure the stability of hydraulic structure against uplift pressure and piping phenomenon in addition to the sliding and overturning forces of the water. These cutoffs are used at critical sections underneath the floor of hydraulic structure to substitute with their depths the horizontal lengths of the creep line of the hydraulic structure base.In this paper,the experimental method-by using electrical analogue model-was carried out to plot the flow net and study the efficiency of the front and rear faces of the cutoffs for dissipating the potential energy of the percolating water underneath the floor of hydraulic structure. An electrical analogue model which was used in this study consists of twenty five models with different depths of upstream and downstream cutoffs. After plotting the flow net for all models, it is concluded that the efficiency of the inner sides are less than that of the outer sides which were investigated before in this topic of this work that both faces reduction values in the uplift pressure are considered the same, where the efficiency of the outer face of upstream cutoff is (70.35)% and for the inner face is (29.64)%, while for the downstream cutoff the efficiency for the outer face is (76.21)% and for the inner face is (23.79)% .

Tigris River (downstream of the kut barrage reach) there is no study conducted on it to estimate its Manning n value. HEC-RAS was used to analysis study reach and calibrate n value of the study reach .filed data were collected during 2016-2017 (duration of study), eights data sets were observed included stage and discharge measurements. The discharge is controlled by Kut Barrage Operation. The range of water surface elevation is (+10.300 to +12.511) and flow discharge range is (202.7 -355.280) m3/sec. The range of n value for study reach is (0.021-0.034). The calibration results provided suitable Manning n of 0.026 for downstream of Kut Barrage reach which represent mean value of results.

The present work investigatesthe enhancement of heat transfer by using different number of circular fins(8, 10, 12, 16, and 20) in double tube counter flow heat exchanger experimentally. The fins are made of copper with dimensions 66mm OD, 22mmIDand 1 mm thickness. Each fin has three of 14 mm diameter perforations located at 120o from each to another. The fins are fixed on a straight smooth copper tube of 1 mlength, 19.9mm ID and 22.2mm OD. The tube is inserted inside the insulated PVC tube of 100mmID.The cold water is pumped around the finned copper tube, inside the PVC, at mass flow rates range (0.01019 -0.0219) kg/s. The Reynold's number of hot water ranges (640 -1921). The experiment results are obtained usingsix double tube heat exchanger (1 smooth tube and the other 5 are finned one).The results, illustrated that the heat transfer coefficient proportionallywith the number of fin. The results also showed that the enhancement ratioof heat transfer for finnedtube is higher than for smooth tube with(9.2, 10.2, 11.1, 12.1 13.1) times for number of fins(8,10,12,16and 20) respectively.

The intensity of radiation reaches 930 W/m2 during April, 2016 in Kut city. Thus this city is suitable to use application of solar energy such as solar still. An experimental study was performed to evaluate the production of Semi Spherical Solar Still (SS-SS) with and without Charcoal. It was measured in the climatic conditions of Kut, Wasit (32o N latitude), Iraq. The still consists of square basin of length 0.3 m and area 0.09 m2 made of Aluminum. The square absorber basin is painted with black paint for maximum absorption of incident solar radiation. It was found that the productivity of Semi spherical solar still without charcoal is better than the using of charcoal at depth of basin water (dbw=1.5 & 2cm). The productivity of SS-SS without charcoal was 2.7 lit/m2 for 6 hours at total irradiation 5935 W/m2. Whereas 2.5 lit/m2 for SS-SS with charcoal at total irradiation 5845 W/m2 for dbw=1.5cm. In addition, the instantaneous efficiency reaches 58% without charcoal and 70% with charcoal at dbw=1.5cm at 3:00PM. The salinity of water before desalination in SS-SS was 999.54 ppm and becomes 4.06 ppm after desalination. It could be concluded that the semi spherical solar still can be used for distilled water production.

Modern life and increasing demand on the energy make the saving of available energy in the packed bed of PCM capsules very important to use in the other time. A numerical investigation is proposed for storage of thermal energy using packed bed of spherical capsules filled with phase change material PCM. The spherical capsules are arranged as layers in the cubic vessel that exposed to heat transfer fluid. The fourth order Runge-Kutta method is applied to solve the energy balance equation of heat transferfluid and the energy conservation equation of spherical capsules of PCM is solved using finite differences method with heat capacity method for phase change of PCM. The effect of Reynolds number and diameter of capsulated sphere are studied. The results illustrate that at constant porosity of packed bed the small diameter of capsulated spheres gives shorter time for melting, where at D=50mm & t=196.5sec the melting fraction of PCM is 0.09, while at D=10mm & t=196.5sec the melting fraction of PCM is 1.00. The results of present study have been compared with other previous results and give a good agreement.

Face recognition is the process of finding the face of one or more people in an image or even in a video. There are variety techniques for face recognition used in the researches. In this paper various algorithms for face recognition on mobile phones or other electronic device are applied. firstly the face detection should be implemented in any face recognition system. To get the face detection many algorithms like color segmentation, template matching etc are applicated. Then the second phase of the proposed algorithm is implemented by using neural network Gabor with fuzzy system. The algorithm has been represented using MATLAB and then implemented it on the device.While implementing the proposed algorithm, a tradeoff between accuracy and computational complexity of the algorithm are made, because the face recognition system is implemented on a device with limited hardware capabilities

In this work, experimental investigation and numerical prediction were completed to study the heat transfer for disturbed flow in square passage heated from upper and lower aspect through the use of technology to heighten the heat transfer action by the use of different ribs shapes (semicircle, triangular and square) with the same surface area and height, distributed on the superior and inferior aspect of the heated channel. The experimental part included designing and manufacturing test apparatus and run the tests through operational parameters (Reynolds number 10460-40500) and heat flux (138-6888) W/m2. While the design parameters included different ribs shapes (circular, triangular and square). Numerical investigation was done by using ANSYS FLUENT14.0 program, depending on Navier–Stokes equations, application of turbulence model k-ε and energy equation for the air were implemented for the same experimental conditions for all ribs type. In conclusion, the additions of ribs make noticeable enhance of the heat transfer compared to without ribs. Square ribs provide the best enhancement in heat transfer by (28.22-58.23) % compared to without ribs. Then comes the triangular and circular ribs that provide enhancement by (20.14-45.62) (10.87-28.13) % respectively. In addition to that, arrange the ribs in staggered pattern on the upper and lower aspect give the best heat transfer.