In this paper I use a mathematical model to simulate the effect of wind and altitude on men's and women's 4400-m race performances. Both wind speed and direction were altered to calculate the effect on the velocity profile and the final time of the sprinter. The simulation shows that for a constant wind velocity, changing the wind direction can produce a large variation in the race time and vel...

KHALED HOSSEINI has been widely acclaimed for his debut novel The Kite Runner, an international best-seller. The novel not only launched Hosseini into the limelight as an Afghan-American writer but also bridged the gap between Western literary audience and the culture of the Middle East. The novel is about the friendship of two Afghan boys through the decades, and Amir, the narrator is an expat...

Forces that are repeatedly applied to the body could lead to positive remodeling of a structure if the forces fall below the tensile limit of the structure and if sufficient time is provided between force applications. On the other hand, an overuse injury could result if there is inadequate rest time between applied forces. Running is one of the most widespread activities during which overuse i...

We analyze a model of fault-tolerant systems in a probabilistic setting. The model has been introduced under the name of “sabotage games”. A reachability problem over graphs is considered, where a “Runner” starts from a vertex u and seeks to reach some vertex in a target set F while, after each move, the adversary “Blocker” deletes one edge. Extending work by Löding and Rohde (who showed PSpace...

Hydropower plants (HPPs) contribute a significant share of Russia’s electricity generation. With the prospects developing this sector and harnessing hydroenergy potential, it is necessary to consider methods for modernizing hydroelectric installations. This article examines new method regulating active (Pelton) turbines based on modifying nozzle flow rate through ejection spent liquid from runn...

The article describes the inflow turbines as reliable, productive, small-sized drives for various units and devices. practice of manufacturing using turbine stages sets out goal increasing efficiency, simplifying technology reducing cost stages. Increasing efficiency requires solving problems improving flow part calculating optimal geometry operating modes impeller flow. A significant low-consu...

Experimental tests in prototype are necessary to understand the dynamic behaviour of the machine during different operating points. Hydraulic phenomena as well as its effect on the structure need to be studied in order to avoid instabilities during operation and to extend the lifetime of the different components. For this purpose, a complete experimental study of a large Francis turbine prototy...

This paper presents the software package developed at Fluid and Power Research Institute (FPRI) for the uid mechanical design of the wicket gates and the runner blades of the Potential Flow turbine [1]. This software package is based on the correct formulation of the design problem. The design problem can not be correctly formulated for Francis and Kaplan turbines with conventional wicket gates...