Aircraft is a machine which is able to by gaining support from the air or atmosphere on the earth. Tha human activity that surrounds an aircraft is called as aviation. The design of aircrafts is done by many factors such as demand, safety protocols, and physical constraints. They use buoyancy to float in the air as the way ships float an water. There are many types of aircrafts and are light weight pistons or gas turbines. High-impact journals are those considered to be highly influential in their respective fields. The impact factor of journal provides quantitative assessment tool for grading, evaluating, sorting and comparing journals of similar kind. It reflects the average number of citations to recent articles published in science and social science journals in a particular year or period, and is frequently used as a proxy for the relative importance of a journal within its field. It is first devised by Eugene Garfield, the founder of the Institute for Scientific Information. The impact factor of a journal is evaluated by dividing the number of current year citations to the source items published in that journal during the previous two years.
Last date updated on July, 2014