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991.
992.
In this paper, we have successfully presented a fuzzy Petri net (FPN) model to design the genetic regulatory network. Based on the FPN model, an efficient algorithm is proposed to automatically reason about imprecise and fuzzy information. By using the reasoning algorithm for the FPN, we present an alternative approach that is more promising than the fuzzy logic. The proposed FPN approach offers more flexible reasoning capability because it is able to obtain results with fuzzy intervals rather than point values. In this paper, a novel model with a new concept of hidden fuzzy transition (HFT) to design the genetic regulatory network is developed. We have built the FPN model and classified the input data in terms of time point and obtained the output data, so the system can be viewed as the two-input and one output system. This method eliminates possible false predictions from the classical fuzzy model thereby allowing a wider search space for inferring regulatory relationship. The experimental results show the proposed approach is feasible and acceptable to design the genetic regulatory network and investigate the dynamical behaviors of gene network. 相似文献
993.
?smail Dinçer 《Advances in Engineering Software》2011,42(4):160-171
Determination of deformation modulus and coefficient of subgrade reaction of soils have major importance, whether the projects are in design, and construction or compaction assessment stage of earth filling structures. Plate load test is one of the frequently used method to directly determine the parameters but the method is both costly and time consuming. For this reason, this paper is concerned with the applications of artificial neural networks (ANN) and simple-multiple regression analysis to predict deformation modulus and coefficient of subgrade reaction of compacted soils from compaction parameters (such as maximum dry density (MDD) and optimum moisture content (OMC), field dry density (FDD), and field moisture content (FMC)). Regression analysis and artificial neural network estimation indicated that there are acceptable correlations between deformation modulus and coefficient of subgrade reaction and these parameters. Artificial neural networks model exhibits higher performance than traditional statistical model for predicting deformation modulus and coefficient of subgrade reaction. 相似文献
994.
In this study, a novel OFF-set based direct-cover Exact Minimization Algorithm (EMA) is proposed for single-output Boolean functions represented in a sum-of-products form. To obtain the complete set of prime implicants covering the given Target Minterm (ON-minterm), the proposed method uses OFF-cubes (OFF-minterms) expanded by this Target Minterm. The amount of temporary results produced by this method does not exceed the size of the OFF-set. In order to achieve the goal of this study, which is to make faster computations, logic operations were used instead of the standard operations. Expansion OFF-cubes, commutative absorption operations and intersection operations are realized by logic operations for fast computation. The proposed minimization method is tested on several classes of benchmarks and then compared with the ESPRESSO algorithm. The results show that the proposed algorithm obtains more accurate and faster results than ESPRESSO does. 相似文献
995.
996.
Well-known results on the avoidance of large squares in (full) words include the following: (1) Fraenkel and Simpson showed that we can construct an infinite binary word containing at most three distinct squares; (2) Entringer, Jackson and Schatz showed that there exists an infinite binary word avoiding all squares of the form xx such that |x|≥3, and that the bound 3 is optimal; (3) Dekking showed that there exists an infinite cube-free binary word that avoids all squares xx with |x|≥4, and that the bound of 4 is best possible. In this paper, we investigate these avoidance results in the context of partial words, or sequences that may have some undefined symbols called holes. Here, a square has the form uv with u and v compatible, and consequently, such a square is compatible with a number of full words that are squares over the given alphabet. We show that (1) holds for partial words with at most two holes. We prove that (2) extends to partial words having infinitely many holes. Regarding (3), we show that there exist binary partial words with infinitely many holes that avoid cubes and have only eleven full word squares compatible with factors of it. Moreover, this number is optimal, and all such squares xx satisfy |x|≤4. 相似文献
997.
Jan Kapa?a 《Calphad》2011,35(2):219-223
The thermodynamic properties of ABr-PrBr3(A=Li-Cs) systems were assessed by the CALPHAD method. The liquid phase in the systems was described by the non-stoichiometric associate model. The entropies of mixing in the liquid were evaluated from experimental liquidus and enthalpy of mixing data. For the pseudobinary compounds A3PrBr6,APr2Br7, and A2PrBr5 (A=K,Rb) and Cs3PrBr6 and CsPr2Br7, the dependences of Gibbs energies of formation on temperature were calculated. The anomalies of sequences of thermodynamic properties in RbBr-PrBr3 were observed and discussed. The nature of the liquid phase and precision of calculations of the Rb2PrBr5(s) compound were discussed. 相似文献
998.
R?zvan Diaconescu 《Information and Computation》2011,209(2):108-117
We develop a combination, called hidden preordered algebra, between preordered algebra, which is an algebraic framework supporting specification and reasoning about transitions, and hidden algebra, which is the algebraic framework for behavioural specification. This combination arises naturally within the heterogeneous framework of the modern formal specification language CafeOBJ. The novel specification concept arising from this combination, and which constitutes its single unique feature, is that of behavioural transition. We extend the coinduction proof method for behavioural equivalence to coinduction for proving behavioural transitions. 相似文献
999.
In this paper, we develop a so-called Entropy-TVD scheme for the non-linear scalar conservation laws. The scheme simultaneously
simulates the solution and one of its entropy, and in doing so the numerical dissipation is reduced by carefully computing
the entropy decrease. We prove that the scheme is feasible and TVD and satisfies the entropy condition. We also prove that
the local truncation error of the scheme is of first-order. However, numerical tests show that the scheme has a second-order
convergence rate, an order higher than its truncation error, in computing smooth solution, and in many cases is better than
a second-order ENO scheme in resolving shocks and corners of rarefaction waves. 相似文献
1000.
In this paper, we study Bézier surfaces in three-dimensional Minkowski space. In particular, we focus on timelike and spacelike cases for Bézier surfaces. We also deal with the Plateau–Bézier problem in , obtaining conditions over the control net to be extremal of the Dirichlet function for both timelike and spacelike Bézier surfaces. Moreover, we provide interesting examples showing the behavior of the Plateau–Bézier problem in and illustrating the relationship between it and the corresponding Plateau–Bézier problem in the Euclidean space R3. 相似文献