Spillways usually used for escaping water from the U.S. having a high-water level, to D.S. having a low water level in most of the diversion head structures through water streams. The D.S. of such spillways usually suffers from the destructive impacts of the generated kinetic energy of the flowing water, having a very high speed, which may cause cavitation in such spillways body. In the present work, some geometrical treatments on the back of the spillway body, are introduced for increasing its efficiency in dissipating the kinetic energy of the flowing water, having great potential energy, and improving the flowing water quality by increasing its dissolved oxygen content, through generating huge aeration at the flow in the back, in addition to prevent cavitation which may occur, and generated on the back of the spillway body. Previous studies proved that the stepped back of the spillway body is one of the most practicable trails done for achieving the above-mentioned goals. In this paper, a review of previous authors` technical methods to obtain the best design of the spillway geometric that dissipates high values of the kinetic energy and improving the flow aeration.is highlighted.

The research for alternative fuels increased rapidly to mitigate the pollution problems resulting from using conventional fuels in internal combustion engines. Natural gas (NG) appears the most promising alternative due to its low prices and availability around the world. In this paper, a two-zone, zero-dimensional (0-D) model for the simulation of dual fuel NG-diesel engine is developed to study the performance of the engine with a proposed technique of NG early direct injection. The model is composed of several sub-models that are based on semi-empirical formulas. NG is modeled as being directly injected at the beginning of the compression stroke. The model is applied to study the performance of HELWAN M-114 diesel engine using dual fuel of NG and diesel fuels as a case study. The results indicate that using NG early direct injection technique (EDI) results in increasing the volumetric efficiency and hence the brake power of the engine compared to the intake manifold induction (IMI) of NG with air through the intake manifold. The percentage increase in brake power is 8.7% at NG mass ratio in the total fuel (the supplement ratio (SR)) of 90% at full load. To evaluate the proposed technique, results obtained by varying the engine load and the SR. Results indicate that the slow burning rate of NG results in decrease in the brake thermal efficiency by 3.5% and increases in brake specific fuel consumption with a percentage of 10.2% at 90% SR and full load. However, a great advantage of increasing the SR is the reduction in NOx and soot emissions particularly at high engine loads where they were reduced with percentages of 28.6% and 86%, respectively at 90% SR and full load condition.

This paper introduces a design for an ultralowpower electromyogram (EMG) signal amplifier with low noise operation. The design consists of two stages, the first stage is highly efficient but supply-sensitive single ended amplifier and the second stage is differential, to improve the supply rejection ratio and common mode rejection ratio. Each stage is configured with cascode MOSFET transistors to increase the gain value. The proposed design is simulated by 130 nm CMOS, and its results are reported. The design achieves 60.62 dB mid-band gain with bandwidth of 1.72kHz. Using a supply voltage of 1.1 V, the amplifier consumes 1.03 μA of current. Input referred noise is 3.006 μVrms. The common mode and power supply rejection ratios are above 49.05 dB and 55.72 dB respectively.

This study aims to explore the cyclic bond–slip behavior of basalt fiber-reinforced polymers (BFRP) bars. Experimental pullout tests under monotonic and cyclic loading patterns were conducted in order to examine the effect of the cyclic loading on the bond behavior of BFRP bars. The effects of cyclic loading characteristics, concrete compressive strength, and bar diameter on the bond–slip relationship were examined. In addition, the bond performance of bars with four different surface profiles (smooth, sand-coated, wrapped, and wounded) under different loading protocols was studied and compared to that of deformed steel bars. The results revealed that cyclic loading had a significant effect on the bond performance of BFRP bars and the bond–slip relationship was greatly dependent on the bar surface treatment, as well as the characteristics of the applied cyclic loading protocol. Also, cyclic loading magnified the effect of concrete compressive strength on the bond behavior. A numerical model was proposed to predict the bond–slip relationship of wounded BFRP bars under cyclic loading. The model predictions showed good agreement with experimental results.

The dimensions of many water streams, which satisfy the proper hydraulic condition, may not be compatible with the designed dimensions of an irrigation work needed to be constructed in some locations. The design requirements of such irrigation works may need to make a contraction in the channel width in the location of constructions. This contraction, of course, affects the different flow properties and the scour hole formed downstream these structures. So, the present experimental study aims to investigate the effect of the transition angle and the contraction ratio on the flow properties and on the scour phenomenon downstream water structures. Through 454 experimental runs, carried out on 20 experimental models, the study proved that, for an efficient hydraulic performance and economic design, the best transition angle (θ) for the approaches of water structures is 30° with a contraction ratio (r) not less than 0.6.

This study provides a methodology to incorporate the dynamic bus stop simulation into a proposed static transit assignment model. It tries to combine the merits of the realism of dynamic models and the simplicity of static models in a single framework. An algorithm is developed to simulate any load profile of both passenger and bus arrivals. Then, the simulation results are used within the transit assignment process to allow a better line choice representation. A detailed illustrative example is given to validate the proposed assignment methodology performance. The resulted flows in some cases exceed lines capacity while conserving the static equilibrium principles. This capacity violation interprets the fact that some passengers may fail to board the first incoming bus of their desired line due to insufficient capacity. However, they wait until a vacant space is offered on the same line. In addition, a benchmark problem is solved to ease the comparison between the proposed methodology and the existing methodologies. It shows the methodology capability of incorporating different waiting time models to produce passengers’ flow on transit lines. It also indicates the importance of lines that might be neglected in other transit assignment models. This would highlight the methodology interpretation of passengers’ behavior in transit networks.

Despite all modern techniques in registering terrestrial laser scanner point clouds, registration of multiple scan positions is still a crucial issue, especially in large projects. Processes like the detection of corresponding points in scans and placing targets in fields consume a lot of effort, time and money. Three points are the minimum number of common points required for registration. In this work, a new two points registration (TPR) algorithm is developed to register terrestrial laser scanner point clouds using only two common points automatically. Decreasing the number of the required common points to two points reduces one-third of the registration work in both field and laboratory. An accuracy assessment study is then performed to compare the registration accuracy of the developed algorithm and the traditional algorithm employing both the time of flight laser scanner and the phase shift one. The results show that the accuracy of the two algorithms is approximately equal within the considered point clouds accuracy in both cases.

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