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Algebraic characterization of logic programs has received increasing attention in recent years. Researchers attempt to exploit connections between linear algebraic computation and symbolic computation to perform logical inference in large-scale knowledge bases. In this paper, we analyze the complexity of the linear algebraic methods for logic programs and propose further improvement by using sparse matrices to embed logic programs in vector spaces. We show its great power of computation in reaching the fixed point of the immediate consequence operator. In particular, performance for computing the least models of definite programs is dramatically improved using the sparse matrix representation. We also apply the method to the computation of stable models of normal programs, in which the guesses are associated with initial matrices, and verify its effect when there are small numbers of negation. These results show good enhancement in terms of performance for computing consequences of programs and depict the potential power of tensorized logic programs. [ABSTRACT FROM AUTHOR]

The article focuses on a study which explores preferences and willingness-to-pay (WTP) of patients with heart diseases for different home- and hospital-based services in Vietnam. It mentions that WTP for treatment and care services among heart disease patients are low especially with regard to administrative and home-based services. It states that WTP of patients for services was also found to be influenced by education level, occupation, and whether in- or outpatient service was utilized.

When the effects of physical aging below Tg are erased, the rheological response of a series of aliphatic hyperbranched polyesters is Newtonian and the melt viscosity scales roughly linearly with Mw at high Mw, indicating entanglement to be absent. The rheological behavior is also highly sensitive to the nature of the terminal groups, suggesting the overall behavior to be close to that of an assembly of compact coreshell "particles". There are therefore strong parallels between the physical behavior of the hyperbranched polyesters in question and that of their ideal dendrimer analogues. [ABSTRACT FROM AUTHOR]