Tham khảo tài liệu 'the mems handbook mems applications (2nd ed) - m. gad el hak episode 2 part 7', kỹ thuật - công nghệ, cơ khí - chế tạo máy phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | Flow Control 13-35 coherent structures in chaotic fluid systems. The key idea to create such structures is to intentionally place folds of horseshoes near low-order periodic points. In a dissipative dynamical system volumes contract in state space and the co-location of a fold with a periodic point leads to an isolated region that contracts asymptotically to a point. Provided that the folding is done properly it counteracts stretching. Shinbrot and Ottino 1993a applied the technique to three prototypical problems a one-dimensional chaotic map a two-dimensional one and a chaotically advected fluid. Shinbrot 1995 1998 and Shinbrot et al. 1998 provide recent reviews of the stretching folding as well as other chaos control strategies. Soft Computing The term soft computing was coined by Lotfi Zadeh of the University of California Berkeley to describe several ingenious modes of computations that exploit tolerance for imprecision and uncertainty in complex systems to achieve tractability robustness and low cost Yager and Zadeh 1992 Bouchon-Meunier et al. 1995a 1995b Jang et al. 1997 . The principle of complexity provides the impetus for soft computing as the complexity of a system increases the ability to predict its response diminishes until a threshold is reached beyond which precision and relevance become almost mutually exclusive Noor and Jorgensen 1996 . In other words precision and certainty carry a cost. By employing modes of reasoning probabilistic reasoning that are approximate rather than exact soft computing can help in searching for globally optimal design or achieving effectual control while taking into account system uncertainties and risks. Soft computing refers to a domain of computational intelligence that loosely lies between purely numerical hard computing and purely symbolic computations. Alternatively one can think about symbolic computations as a form of artificial intelligence lying between biological intelligence and computational .
