The present experimental study was executed to investigate a new and untested shape of curved dissipators with different angles of curvature and arrangements from the following two points of view: (i) To examine its efficiency in dissipating the kinetic water energy; (ii) To examine the most effective shape and arrangement obtained from the above mentioned step in enriching the flow with dissolved oxygen for enhancing the irrigation water quality. The study was held in the irrigation and hydraulic laboratory in the Civil Department, Faculty of Engineering, Assiut University, using a bed tilting channel 20 m long, 30 cm wide and 50 cm height, using 20 types of curved dissipators with different arrangements. A total of 660 runs were carried out with different discharges. Results, in general, showed that, for the same angle of curvature, the dissipator performance is more tangible in dissipating the water energy when the curvature is in the opposite direction of the flow. Also, the energy loss ratio increases with the increase of the dissipator curvature angle (θ), till it reaches (120°), then it decreases again. The study also showed that using four rows of dissipators gives nearly the same effect of using three rows concerning both, the relative energy dissipation and dissolved oxygen content. So, it is recommended to use not more than three rows of the introduced curved dissipator with an angle of curvature equals (120°) in the opposite direction of the flow to obtain the maximum percentage of water energy dissipation downstream head structures and maximum dissolved oxygen content. Also, the study showed that, using the new introduced curved dissipator in three rows in the staggered-separate manner gives the best formed hydraulic jump characteristics, less relative depth and less relative length than all other tested dissipators, which reduces the cost of construction of the solid apron on the downstream side of head structure.

The present experimental study was executed to investigate a new and untested shape of curved dissipators with different angles of curvature and arrangements from the following two points of view: (i) To examine its efficiency in dissipating the kinetic water energy; (ii) To examine the most effective shape and arrangement obtained from the above mentioned step in enriching the flow with dissolved oxygen for enhancing the irrigation water quality. The study was held in the irrigation and hydraulic laboratory in the Civil Department, Faculty of Engineering, Assiut University, using a bed tilting channel 20 m long, 30 cm wide and 50 cm height, using 20 types of curved dissipators with different arrangements. A total of 660 runs were carried out with different discharges. Results, in general, showed that, for the same angle of curvature, the dissipator performance is more tangible in dissipating the water energy when the curvature is in the opposite direction of the flow. Also, the energy loss ratio increases with the increase of the dissipator curvature angle (θ), till it reaches (120°), then it decreases again. The study also showed that using four rows of dissipators gives nearly the same effect of using three rows concerning both, the relative energy dissipation and dissolved oxygen content. So, it is recommended to use not more than three rows of the introduced curved dissipator with an angle of curvature equals (120°) in the opposite direction of the flow to obtain the maximum percentage of water energy dissipation downstream head structures and maximum dissolved oxygen content. Also, the study showed that, using the new introduced curved dissipator in three rows in the staggered-separate manner gives the best formed hydraulic jump characteristics, less relative depth and less relative length than all other tested dissipators, which reduces the cost of construction of the solid apron on the downstream side of head structure.

The present experimental study was executed to investigate a new and untested shape of curved dissipators with different angles of curvature and arrangements from the following two points of view: (i) To examine its efficiency in dissipating the kinetic water energy; (ii) To examine the most effective shape and arrangement obtained from the above mentioned step in enriching the flow with dissolved oxygen for enhancing the irrigation water quality. The study was held in the irrigation and hydraulic laboratory in the Civil Department, Faculty of Engineering, Assiut University, using a bed tilting channel 20 m long, 30 cm wide and 50 cm height, using 20 types of curved dissipators with different arrangements. A total of 660 runs were carried out with different discharges. Results, in general, showed that, for the same angle of curvature, the dissipator performance is more tangible in dissipating the water energy when the curvature is in the opposite direction of the flow. Also, the energy loss ratio increases with the increase of the dissipator curvature angle (θ), till it reaches (120°), then it decreases again. The study also showed that using four rows of dissipators gives nearly the same effect of using three rows concerning both, the relative energy dissipation and dissolved oxygen content. So, it is recommended to use not more than three rows of the introduced curved dissipator with an angle of curvature equals (120°) in the opposite direction of the flow to obtain the maximum percentage of water energy dissipation downstream head structures and maximum dissolved oxygen content. Also, the study showed that, using the new introduced curved dissipator in three rows in the staggered-separate manner gives the best formed hydraulic jump characteristics, less relative depth and less relative length than all other tested dissipators, which reduces the cost of construction of the solid apron on the downstream side of head structure.

The inlet and exit geometry of the pipe or circular culverts has a significant importance in improving its performance, and increasing its efficiency. That is why the present experimental study focuses on testing the influence of equipping an inclined headwall in such culverts on the hydraulic efficiency, and comparing the results with the projected culvert (culvert without headwall). The present research consists of three trends of experiments, the first one for testing the effect of equipping an inclined headwall in the U.S. side of the circular culvert, while the second trend for testing the effect of equipping an inclined headwall in the D.S. side of the circular culvert, and the third trend was for testing the effect of equipping an inclined headwall in both sides of the circular culvert (U.S. and D.S.). In each trend, there are five models of headwall with variable inclination angle ranging from 15° to 90° were used in addition to the projected one as a reference for comparison purposes with a total of 240 runs. The study introduced a new effective tool for improving the circular culvert efficiency and insuring more safety for the traffic over such roads. The study showed that, the headwall of inclination angle 15° in the opposite direction of the flow gives the best results and the maximum discharge efficiency under the same upstream water depth in case of using U.S. headwall only, while for using the headwalls in both sides of the circular culvert, the inclination angle of 60° is the best one. But, using the headwall in the D.S. side only has a negative impact on the hydraulic efficiency of the circular culvert.

Abstract Objective: This study was performed to evaluate the feasibility and safety of early sheath removal after percutaneous coronary intervention (PCI) using a locally designed Assiut Femoral Compression Device (AFCD2) vs. manual compression (MC). Background: Due to antithrombotic therapy before, during, and after PCI, the arterial femoral sheath is generally not removed early after PCI. Patients and methods: This was a randomized, controlled trial. We enrolled all patients undergoing PCI at Assiut University Hospitals from September, 2013 to December, 2013. At the end of PCI, the arterial hemostasis method was randomly assigned 1:1 to AFCD2 vs. MC. The sheaths were removed 2 h after PCI, instead of conventional 6 h, in the AFCD2 arm. Results: The trial assigned 100 patients (mean age 57± 9 years, 75% men) to AFCD2 (n= 50) vs. MC (n= 50). Both groups were comparable regarding baseline characteristics. Concerning the primary effectiveness end point, there was significantly shorter mean time-to-ambulation with AFCD2 (8.2 ± 1.42 h) vs. MC (12.02± 0.22 h; p= 0.001). This was directly reflected on shorter time for hospital discharge eligibility in AFCD2 (11 ±1 h) vs. MC (15 ±1 h; p= 0.001). As regards safety, none of our research population experienced major adverse events. The use of AFCD2 was associated with similar occurrence of minor complications, mainly ecchymosis and oozing, compared with MC.

Abstract: This study demonstrates variable speed variable pitch horizontal axis wind turbine operating ranges, concerned on increasing the output power generated by the turbine. To achieve these approaches two control techniques summarized. The resultant technique was applied on a model for commercial wind turbine ‘Aeolos 50 kw’ was built on simulink. The simulation results show that the developed strategy is better than the classical strategies.

Abstract: This study demonstrates variable speed variable pitch horizontal axis wind turbine operating ranges, concerned on increasing the output power generated by the turbine. To achieve these approaches two control techniques summarized. The resultant technique was applied on a model for commercial wind turbine ‘Aeolos 50 kw’ was built on simulink. The simulation results show that the developed strategy is better than the classical strategies.

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