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This study investigated the flow around river's floodplain single groynes. Two different compound channels with one and two symmetrical floodplains having widths of 1-and 2-times of the main channel width, respectively, were used. Both impermeable and permeable groynes with three different relative lengths (relative to the floodplain width) and having three different permeability values of 40, 60, and 80% were investigated. The 3D flow velocities were measured in the horizontal plane at 0.25 and 0.5 of floodplain water depth (hf), and in the vertical plane at the main channel's centerline. Therefore, the flow velocities in the longitudinal, lateral, and vertical directions, and the flow water surfaces were measured and analyzed. The results showed that, as the groyne permeability increased up to 60%, a reduction of up to 30% to the maximum velocity and 22 % to the tip velocity were observed. The permeable groyne length had limited influence on the flow structure. Both the groyne permeability and the length ratio had significant effects on the floodplain water depth. The scouring and the deposition activities resulting from impermeable groynes can be avoided, should the groyne length be kept below half of the floodplain width.

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Real-time, static and dynamic hand gesture learning and recognition makes it possible to have computers recognize hand gestures naturally. This creates endless possibilities in the way humans can interact with computers, allowing a human hand to be a peripheral by itself. The software framework developed provides a lightweight, robust, and practical application programming interface that helps further research in the area of human-computer interaction. Approaches that have proven in analogous areas such as speech and handwriting recognition were applied to static and dynamic hand gestures. A semisupervised Fuzzy ARTMAP neural network was used for incremental online learning and recognition of static gestures; and, Hidden Markov models for online recognition of dynamic gestures. A simple anticipatory method was implemented for determining when to update key frames allowing the framework to work with dynamic backgrounds.

Given the growing interest in river restoration and natural river improvement, groins are recommended as an essential hydraulic component for creating riparian habitats and controlling local flow. The optimum design of groins for environmental purposes is still not defined despite its long history of improving river flow dynamics. The primary goal of this paper is to determine the influence of hybrid groins' orientation angle and geometry on both the flow velocity and structure to enhance fish habitat. This study investigates six models of unsubmerged hybrid L-shape groins installed in a straight channel with a deformed bed. The hybrid L-shape groins consist of two parts, an impermeable part that objected to the flow, and a permeable one (piles rows) arranged in the flow direction. The influences of groin's both contraction/length ratio and orientation angle on the flow velocity and structure are studied. The contraction ratio represents the impermeable groin length relative to channel width (W/B), while the orientation angle (θ) is the groin inclination angle in the up/downstream direction. Groin models with 25% contraction ratio and up/downstream orientation angle (θ) of 45°, 60°, and 90° were used. Groin with an orientation angle of 45° toward downstream has introduced the highest reduction on the flow velocities. Also, groin with θ=90° downstream introduced low velocities, but these velocities still more than the reduction of 45° case. The area of the dead zone -the zone of low velocities-in the case of θ=45° is about 70 % more than that of θ=90°.

Good management of flash floods requires accurate estimation for both the hazard degrees and flood risk maps. Morphological parameters greatly affect the strength of flood's hydrograph and accordingly the flash flood hazard degree. This study uses decision-making tools such as Multi Criteria Analysis (MCA) and/or Multi-Attribute Utility Theory (MAUT) to estimate the Gulf of Suez's flash flood hazard degree, Sinai Peninsula, Egypt. The MAUT was applied successfully in estimating the hazard degrees of 56 basins in the coastal zone of the Suez Gulf. Based on the resulted correlation between all hydro-morphological parameters, only six equal weight parameters were selected and used to calculate the hazard degree. The results showed that, about 40 % of the 56 basins have high or moderately high hazard degree. Values of the correlation factors between the hydro-morphological parameters and the resulted hazard degrees are ranged between 0.813 for basin's Sinuosity and 0.011 for Centroid Stream Slope. The weights of those parameters were non-linearly optimized to make the correlation of all chosen parameters with the hazard degree higher than or equal to the threshold value (0.6). Accordingly, percentage of basins with high or moderately high hazard degree have decreased to 32 %. Capability and validation of current model have been achieved using the damage information of some flood events in the last few decades. The comparison between current model's scenarios and flood events showed that, all the affected basins that had high or moderated high hazard degree are highly coincide with the real cases.

Patients undergoing robotic‐assisted coronary artery bypass grafting are increasing. Several complications have emerged with the increasing use of minimally invasive procedures. We reported a case of spontaneous tension pneumothorax that developed in the ventilated lung during robotic assisted left internal mammary artery harvesting causing severe hemodynamic instability. A sudden rise of airway pressure occurred, and the patient became hypotensive. Immediately, the surgeon was notified to look at the right pleura. Pneumothorax was identified, the right pleura was opened using robotic arms, and the right lung was decompressed. A small emphysematous bulla was identified and stabled. Proper identification of the procedure‐associated complications is essential for timely management. Tension pneumothorax is a potentially fatal complication, especially in patients under positive pressure ventilation.

Presented herein are the results of an experimental study on the flow characteristics around compound channel floodplain groynes with various permeability and length. Both the permeable and impermeable groynes are considered to clarify the influences of floodplain groynes on flow structure, velocity, and water surface. A channel consisting of a main channel and one floodplain with flat and fixed bed was used. The width of floodplain is the same as the main channel width. Pile groyne models with three different relative lengths relative to floodplain width (L r), 0.5, 0.75, and 1.0, with three different permeability values (P= area of water crossing the groyne/total projected area of groyne) 40%, 60%, 80% plus an impermeable groyne were used and installed in the floodplain with single arrangement. The 3D flow velocities at both of the horizontal plane above floodplain bed by 0.25 of floodplain water depth (h) and at the main channel centerline in the vertical plane were measured using an Acoustic Doppler Veloci-meter (16 MHz Micro-ADV). The flow pattern around groynes was analyzed in both the horizontal and vertical planes. The results show that, for permeable groynes as the permeability increased the groyne length has limited influence on the flow structure. For the horizontal plane maximum and tip velocities were decreased while the minimum and bank velocities were increased as the permeability increased. Empirical formulas to describe these relations depending on the groyne relative length and permeability were suggested. The influence of permeable groynes installation in the compound channel has insignificant effect on the main channel flow while the impermeable groynes affect greatly the main channel flow structure. Both the groyne permeability and length ratio have obvious effects on the floodplain water depth.