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We investigate the problem of a widespread occurrence of an unknown worm in vehicular networks at equilibrium traffic. We introduce an intelligent microscopic mobility and consider the fading effect in channel model; meanwhile we design a new series of rules to imitate the most relevant aspect of medium access control. The extensive Monte Carlo simulations uncovered the impacts of the transmission range (from minimum to maximum), the velocity (from free to congested), and the vehicle density (from sparse to dense) on worm spreading.

The incorrectness of function grading in value engineering has been an essential problem for decades. This paper proposes a new method, where the functions under consideration are ranked in queue according to their importance and then graded quantitatively. By using this method, the reviewers are more aware of the degrees of importance, and therefore will have an easier time grasping the standard and reducing the erroneous grading. In the first step, the sign test is used to discard incorrect data, to count the grading result and to arrange in queue according to the degrees of functional importance. In the second step the queued up functions undergo quantitative grading, where the “average value of fluctuation coefficient” is proposed to determine the control levels and to delete unreasonable data outside the controlled region so as to get more satisfactory grading value. The proposed method solves the problem of the incorrectness of function grading in value engineering. It has been proved that the correctness has been raised from the original 70% to over 95%. This new method is not only contributive to the discipline of value engineering but also suitable in the evaluation of technical economy.