1,764 research outputs found
Decay rate asymmetry for in SUSY model
We discuss a rate asymmetry for the radiative -meson decay within the framework of the supersymmetric standard model based on N=1
supergravity. This model contains new sources of CP violation. In spite of
severe experimental constraints on the electric dipole moment of the neutron, a
new CP-violating phase may not be suppressed, leading to a sizable enhancement
of the decay rate asymmetry. The magnitude of the asymmetry is predicted to be
larger than that by the standard model in wide parameter regions where the
branching ratio is consistent with its experimental bounds. A possible maximal
magnitude is about 0.1, which will be well accessible at B factories.Comment: 4 pages, Talk presented at the UK Phenomenology Workshop on Heavy
Flavour and CP Violation, 17 - 22, September 2000, St John's College, Durha
The 1996 U.S. Purse Seine Fishery for Tropical Tunas in the Central-Western Pacific Ocean
The U.S. tropical tuna purse seine fleet has fished the central-western Pacific Ocean under the South Pacific Tuna Treaty since 1988. The 1996 fishery was the poorest since the start ofthe Treaty. Fishing effort declined due to the financial collapse of a large fishing enterprise. Catches reached record lows for yellowfin tuna, Thunnus albacares, and skipjack tuna, Katsuwonus pelamis, and continued a declining trend that started in 1995. Catch rates also decreased to the lowest levels since 1991. Whether this declining trend in catch rates is due to reduced availability of fish caused by cyclic ocean environmental changes affecting vulnerability or to reduced abundance from excessive fishing pressure is not yet known and needs to be assessed
Human Development Dynamics: an Agent Based Simulation of Macro Social Systems and Individual Heterogeneous Evolutionary Games
This is the final version of the article. Available from Springer via the DOI in this record.Purpose In the context of modernization and development, a complex adaptive systems framework can help address the coupling of macro social constraint and opportunity with individual agency. Combining system dynamics and agent based modeling, we formalize a simulation approach of the Human Development (HD) perspective to explore the interactive effects of economics, culture, society and politics across multiple human scales. Methods Based on a system of asymmetric, coupled nonlinear equations, we first capture the core qualitative logic of HD theory, empirically validated from World Values Survey (WVS) data. Using a simple evolutionary game approach, second we fuse endogenously derived individual socio-economic attribute changes with Prisoner’s Dilemma in an agent based model of the interactive political-cultural effects of heterogeneous, spatial intra-societal economic transactions. We then explore a new human development dynamics (HDD) model behavior via quasi-global simulation methods to identify paths and pitfalls towards economic development, cultural plasticity, social and political change behavior. Results Our preliminary results suggest strong nonlinear path dependence and complexity in three areas: adaptive development processes, co-evolutionary societal transactions and near equilibrium development trajectories, with significant implications for anticipating and managing positive development outcomes. Strong local epistatic interactions characterized by adaptive co-evolution, shape higher order global conditions and ultimately societal outcomes. Conclusions Techno-social simulations such as this can provide scholars and policymakers alike insights into the nonlinear, complex adaptive effects of societal co-evolution. We believe complex adaptive or evolutionary systems approaches are necessary to understand both near and potentially catastrophic, far-from-equilibrium behavior and societal outcomes across all human scales of modernization
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