Bayesian inference of a negative quantity from positive measurement results

In this paper the Bayesian analysis is applied to assign a probability density to the value of a quantity having a definite sign. This analysis is logically consistent with the results, positive or negative, of repeated measurements. Results are used to estimate the atom density shift in a caesium fountain clock. The comparison with the classical statistical analysis is also reported and the advantages of the Bayesian approach for the realization of the time unit are discussed.Comment: 10 pages, 4 figures, submitted to Metrologi

Measurement of the Blackbody Radiation Shift of the 133Cs Hyperfine Transition in an Atomic Fountain

We used a Cs atomic fountain frequency standard to measure the Stark shift on the ground state hyperfine transiton frequency in cesium (9.2 GHz) due to the electric field generated by the blackbody radiation. The measures relative shift at 300 K is -1.43(11)e-14 and agrees with our theoretical evaluation -1.49(07)e-14. This value differs from the currently accepted one -1.69(04)e-14. The difference has a significant implication on the accuracy of frequency standards, in clocks comparison, and in a variety of high precision physics tests such as the time stability of fundamental constants.Comment: 4 pages, 2 figures, 2 table

Anchoring Institutions in Agents\u27 Attitudes: Towards a Logical Framework for Autonomous Multi-Agent Systems

The aim of this paper is to provide a logical framework for the specification of autonomous Multi-Agent Systems (MAS). A MAS is autonomous in so far as it is capable of binding (?nomos?) itself (?auto?) independently of any external normative constraint specified by a designer. In particular, a MAS is autonomous if it is able to maintain its social institutions (i.e. rule-governed social practices) only by way of the agents? attitudes. In order to specify an autonomous MAS, we propose the logic AL (Acceptance Logic) in which the acceptance of a proposition by the agents qua group members (i.e. group acceptance) is introduced. Such propositions are true w.r.t. an institutional context and correspond to facts that are instituted in an attitude-dependent way (i.e. normative and institutional facts). Finally, we contend that the present approach paves the way for a foundation of legal institutions, for studying the interaction between social and legal institutions and, eventually, for understanding and modeling institutional change

Cuba in the World, the World in Cuba. Essays in Cuban History, Politics and Culture

The volume approaches Cuba as a nation that hosts a convergence of extraordinary global developments and, in turn, projects itself onto the world's major cultural, political and economic processes. From different perspectives, ranging from architecture and music to politics and economics, the twenty-one essays presented here embrace the multifaceted interactions between Cuba and foreign imperial strategies during the 19th century, the troublesome formation of national political cultures in the first half of the 20th century, and the multiple global aspects of some of Cuba's choices from the Cold War to the first decade of the present century

Levantamento da ocorrência de Sternechus subsignatus no Rio Grande do Sul.

bitstream/item/133935/1/ID43416-1990-1991sojaresultados-p86-94.pdfTrabalhos apresentados na XIX Reunião de Pesquisa de Soja da Região Sul, Pelotas, 1991