β\beta-decay half-lives at finite temperatures for N=82 isotones

Using the finite temperature quasi-particle random phase approximation (FTQRPA) on the basis of finite temperature Skyrme-Hartree-Fock + BCS method, we study $\beta^-$-decay half-lives for even-even neutron magic nuclei with N=82 in a finite temperature environment. We find that the $\beta^-$-decay half-life first decreases as the temperature increases for all the nuclei we study, although the thermal effect is found to be small at temperatures relevant to r-process nucleosynthesis. Our calculations indicate that the half-life begins to increase at high temperatures for open shell nuclei. We discuss this behavior in connection to the pairing phase transition.Comment: 8 pages, 16 figure

Fission barriers in neutron-proton isospin plane for heavy neutron-rich nuclei

We discuss the sensitivity of fission barrier for heavy neutron-rich nuclei to fission paths in the two dimensional neutron-proton quadrupole plane. To this end, we use the constrained Skyrme-Hartree-Fock + BCS method, and examine the difference of fission barriers obtained with three constraining operators, that is, the neutron, proton, and mass quadrupole operators. We investigate $^{220}$U, $^{236}$U, and $^{266}$U, %from proton-rich to neutron-rich uranium isotopes, that is relevant to r-process nucleosynthesis. We find that the fission barrier heights are almost the same among the three constraining operators even for neutron-rich nuclei, indicating that the usual way to calculate fission barriers with the mass quadrupole operator is well justified. We also discuss the difference between proton and neutron deformation parameters along the fission paths.Comment: 6 pages, 7 figure

Chain Reduction for Binary and Zero-Suppressed Decision Diagrams

Chain reduction enables reduced ordered binary decision diagrams (BDDs) and zero-suppressed binary decision diagrams (ZDDs) to each take advantage of the others' ability to symbolically represent Boolean functions in compact form. For any Boolean function, its chain-reduced ZDD (CZDD) representation will be no larger than its ZDD representation, and at most twice the size of its BDD representation. The chain-reduced BDD (CBDD) of a function will be no larger than its BDD representation, and at most three times the size of its CZDD representation. Extensions to the standard algorithms for operating on BDDs and ZDDs enable them to operate on the chain-reduced versions. Experimental evaluations on representative benchmarks for encoding word lists, solving combinatorial problems, and operating on digital circuits indicate that chain reduction can provide significant benefits in terms of both memory and execution time

Constraints to a full adoption of renewable energy: An empirical assessment.

Renewable energy technologies are becoming increasingly important due to uncontrolled exploitation of natural resources worldwide, by human beings, to sustain the current lifestyle. Renewable energy technologies development and acceptance is key to keep the current technological evolutionary pace with responsible use of natural resources. This work is based on identification and test of constraints that have been retaining the acceptance process of renewable energy technologies in Brazil and testing these in organizational environment. For this purpose, the researcher has based its work on behavioural theory i.e. the theory of reasoned action (TRA) (Fishbein and Ajzen, 1975), and theory of planned behaviour (TPB) (Ajzen, 1985). With these in mind, the researcher has adopted the technology acceptance model (TAM) (Davis, 1985) and integrated some extensions to it regarding environmental attitude. The environmental view was considered based on the new environmental paradigm (NEP) (Dunlap and Van Liere, 1978) and the ecologically conscious consumer behaviour model (ECCB) (Roberts, 1996). This research has adopted a mixed methodology using quantitative research and action research via learning sets, gathering data from the environment, referred to technological and environmental challenges identified by the society and using this data as information to an organization so that it could learn and develop new strategies that will help increasing sales of renewable energy technologies' based products. On the quantitative phase of this research, 132 Brazilian citizens living in the south and southeast area of Brazil, with an income not lower than 9 minimum wages, owning graduation degree, responded the quantitative questionnaire. The data collected was analysed using factor analysis and multiple regression which provided information for the Action Research phase, when the organization that participated used learning sets, conducted by the researcher, with a group of sales managers that analysed, debated, developed and applied ideas based on the data of the quantitative questionnaire, aiming the increase of sales of renewable energy technologies' products. The results found consider the constraints of technological acceptance by usefulness or ease of use not high, but greatest challenges lies on price levels and environmental attitude. By looking at these constraints during the learning sets, the organization managed to develop new working strategies for increasing sales of renewable energy technologies' products, such as working with the government for funding and help on price reduction levels and increasing user's environmental knowledge of the importance and benefits that renewable energy technologies' products can bring not only to their businesses but to society