Search

The 2013 9th International Conference on Natural Computation (ICNC'13) and the 2013 10th International Conference on Fuzzy Systems and Knowledge Discovery (FSKD'13) were be jointly held from 23-25 July 2013 in Shenyang, China. http://icnc-fskd.lntu.edu.cn/

OBJECTIVE: To evaluate the effect of strain rate (varepsilon), apparent density (rho(a)) and tissue density (rho(t)) on Young's modulus (E), strength (sigma(u)) and ultimate strain (varepsilon(u)) on intervertebral bone from a Chinese population. METHODS: Testing was performed by uniaxial compression at five strain rates on 36 human trabecular bone specimens from three male T(12) thick similar L(4) vertebrae. RESULTS: Apparent density ranged between 0.46 and 0.71 g/cm(3). Tissue density ranged between 1.02 and 1.54 g/cm(3). Non-linear regression analyses using strength, Young's modulus or ultimate strain as dependent variables (Y) and strain rate and apparent density or tissue density as independent variables were performed using the following equation: Y = arho(b)varepsilon(c). The exponent of apparent density and strain rate to Young's modulus were 1.88 and 0.07, separately (P = 0.0007). The variation of strength was explained only by apparent density with an exponent of 1.29 (P = 0.0107). The variation of Young's modulus was explained equally by the quadratic and cubic relationship to apparent density or tissue density (P0.01). Ultimate strain varied independently of apparent density or tissue density and strain rate.

Neighborhood based rough sets are important generalizations of the classical rough sets of Pawlak, as neighborhood operators generalize equivalence classes. In this article, we introduce nine neighborhood based operators and we study the partial order relations between twenty-two different neighborhood operators obtained from one covering. Seven neighborhood operators result in new rough set approximation operators. We study how these operators are related to the other fifteen neighborhood based approximation operators in terms of partial order relations, as well as to seven non-neighborhood-based rough set approximation operators.