The term stress fracture, in many cases of overuse injury, is a misnomer. This term does not represent the nature and diversity of this frequently found injury. The term, âChronic Repetitive Stress Injury of Boneâ, better suits this injury in its myriad manifestations.he higher grades of stress injury are similar to fatigue fractures of other materials. Bone is noted to fail more readily in tension than in compression. This means that the forces which tend to âpullâ are more dangerous to bone failure and injury than compressive forces.
Wind power or wind energy describes the process by which the wind is used to generate mechanical power or electricity. Wind turbines convert the kinetic energy in the wind into mechanical power.
Wind power has been utilized for thousands of years, starting with the invention of sail boats as the first and most obvious example of making use of wind energy. The earliest known wind powered grain mills and water pumps were used by the Persians in A.D. 500-900 and by the Chinese in A.D. 1200.ith current tax credits, wind energy offers American customers the cheapest electrical energy option. At a cost of $35 per Megawatt hours (MWh), wind is cheaper than coal at $37 per MWh and natural gas at $50 per MWh (in 2004 dollars).