Flexible story generation with Norms and Preferences in computer role playing games

Interactive storytelling is a strength of table-top role playing games as they are facilitated by a game master (GM) who directs the narrative and devises game scenarios. One difficulty with the implementation is the large amount of time

Comparing hurricane and extratropical storm surge for the Mid- Atlantic and Northeast Coast of the United States for 1979–2013

This letter examines the magnitude, spatial footprint, and paths of hurricanes and extratropical cyclones (ETCs) that caused strong surge along the east coast of the US between 1979 and 2013. Lagrangian cyclone track information, for hurricanes and ETCs, is used to associate surge events with individual storms. First, hurricane influence is examined using ranked surged events per site. The fraction of hurricanes among storms associated with surge decreases from 20%–60% for the top 10 events to 10%–30% for the top 50 events, and a clear latitudinal gradient of hurricane influence emerges for larger sets of events. Secondly, surges on larger spatial domains are examined by focusing on storms that cause exceedance of the probabilistic 1-year surge return level at multiple stations. Results show that if the strongest events in terms of surge amplitude and spatial extent are considered, then hurricanes are most likely to create the hazards. However, when slightly less strong events that still impact multiple areas during the storm life cycle are considered, the relative importance of hurricanes shrinks as that of ETCs grows. Furthermore we find distinct paths for ETCs causing multisite surge at individual segments of the US east coast

Quasinormal modes for the charged Vaidya metric

The scalar wave equation is considered in the background of a charged Vaidya metric in double null coordinates $(u,v)$ describing a non-stationary charged black hole with varying mass $m(v)$ and charge $q(v)$. The resulting time-dependent quasinormal modes are presented and analyzed. We show, in particular, that it is possible to identify some signatures in the quasinormal frequencies from the creation of a naked singularity.Comment: 4 pages. Prepared for the proceedings of the Spanish Relativity meeting (ERE2010), Granada, Spain, September 6-10, 201

Quenched Chiral Perturbation Theory for Vector Mesons

We develop quenched chiral perturbation theory for vector mesons made of light quarks, in the limit where the vector meson masses are much larger than the pion mass. We use this theory to extract the leading nonanalytic dependence of the vector meson masses on the masses of the light quarks. By comparing with analogous quantities computed in ordinary chiral perturbation theory, we estimate the size of quenching effects, observing that in general they can be quite large. This estimate is relevant to lattice simulations, where the $\rho$ mass is often used to set the lattice spacing.Comment: 18 pages, 8 figures, uses REVTeX and epsf.st

The conventional wisdom of discharge arbitration outcomes and remedies: fact or fiction

This study examines some of the arbitration community’s commonly accepted beliefs about arbitration outcomes and remedies in employee discharge cases, with the findings revealing that some beliefs are likely fact, while others, perhaps, are fiction. With data from 1432 Minnesota discharge awards and 74 arbitrators who decided them, eight truisms are examined pertaining to the following: the frequency that arbitrators use Daugherty’s Seven Tests rubric to analyze case evidence and whether its use affects award outcomes; the distribution of varying quanta of required proof by arbitrators and how different quanta affects award outcomes; and the effect of employee job tenure and “last chance agreement” status on award outcomes. Using a subsample of “reinstatement with back pay” awards, we additionally examine the prevalence of arbitrators ordering how back pay should be computed and “retaining jurisdiction” over back pay cases

String breaking in Lattice QCD

The separation of a heavy quark and antiquark pair leads to the formation of a tube of flux, or string, which should break in the presence of light quark-antiquark pairs. This expected zero temperature phenomenon has proven elusive in simulations of lattice QCD. We present simulation results that show that the string does break in the confining phase at nonzero temperature.Comment: LATTICE98(hightemp), 3 pages, 4 figures, LaTe

Local Structure of La1-xSrxCoO3 determined from EXAFS and neutron PDF studies

The combined local structure techniques, extended x-ray absorption fine structure (EXAFS) and neutron pair distribution function analysis, have been used for temperatures 4 <= T <= 330 K to rule out a large Jahn-Teller (JT) distortion of the Co-O bond in La1-xSrxCoO3 for a significant fraction of Co sites (x <= 0.35), indicating few, if any, JT-active, singly occupied e_g Co sites exist.Comment: 5 page

Electronic Structure of CeFeAsO1-xFx (x=0, 0.11/x=0.12) compounds

We report an extensive study on the intrinsic bulk electronic structure of the high-temperature superconductor CeFeAsO0.89F0.11 and its parent compound CeFeAsO by soft and hard x-ray photoemission, x-ray absorption and soft-x-ray emission spectroscopies. The complementary surface/bulk probing depth, and the elemental and chemical sensitivity of these techniques allows resolving the intrinsic electronic structure of each element and correlating it with the local structure, which has been probed by extended-x-ray absorption fine structure spectroscopy. The measurements indicate a predominant 4f1 (i.e. Ce3+) initial state configuration for Cerium and an effective valence-band-to-4f charge-transfer screening of the core hole. The spectra also reveal the presence of a small Ce f0 initial state configuration, which we assign to the occurrence of an intermediate valence state. The data reveal a reasonably good agreement with the partial density of states as obtained in standard density functional calculations over a large energy range. Implications for the electronic structure of these materials are discussed.Comment: Accepted for publication in Phys. Rev.

Magnetic Monopoles, Electric Neutrality and the Static Maxwell-Dirac Equations

We study the full Maxwell-Dirac equations: Dirac field with minimally coupled electromagnetic field and Maxwell field with Dirac current as source. Our particular interest is the static case in which the Dirac current is purely time-like -- the "electron" is at rest in some Lorentz frame. In this case we prove two theorems under rather general assumptions. Firstly, that if the system is also stationary (time independent in some gauge) then the system as a whole must have vanishing total charge, i.e. it must be electrically neutral. In fact, the theorem only requires that the system be {\em asymptotically} stationary and static. Secondly, we show, in the axially symmetric case, that if there are external Coulomb fields then these must necessarily be magnetically charged -- all Coulomb external sources are electrically charged magnetic monopoles

The relative influences of disorder and of frustration on the glassy dynamics in magnetic systems

The magnetisation relaxations of three different types of geometrically frustrated magnetic systems have been studied with the same experimental procedures as previously used in spin glasses. The materials investigated are Y$_2$Mo$_2$O$_7$ (pyrochlore system), SrCr$_{8.6}$Ga$_{3.4}$O$_{19}$ (piled pairs of Kagom\'e layers) and (H$_3$O)Fe$_3$(SO$_4$)$_2$(OH)$_6$ (jarosite compound). Despite a very small amount of disorder, all the samples exhibit many characteristic features of spin glass dynamics below a freezing temperature $T_g$, much smaller than their Curie-Weiss temperature $\theta$. The ageing properties of their thermoremanent magnetization can be well accounted for by the same scaling law as in spin glasses, and the values of the scaling exponents are very close. The effects of temperature variations during ageing have been specifically investigated. In the pyrochlore and the bi-Kagom\'e compounds, a decrease of temperature after some waiting period at a certain temperature $T_p$ re-initializes ageing and the evolution at the new temperature is the same as if the system were just quenched from above $T_g$. However, as the temperature is raised back to $T_p$, the sample recovers the state it had previously reached at that temperature. These features are known in spin glasses as rejuvenation and memory effects. They are clear signatures of the spin glass dynamics. In the Kagom\'e compound, there is also some rejuvenation and memory, but much larger temperature changes are needed to observe the effects. In that sense, the behaviour of this compound is quantitatively different from that of spin glasses.Comment: latex VersionCorrigee4.tex, 4 files, 3 figures, 5 pages (Proceedings of the International Conference on Highly Frustrated Magnetism (HFM2003), August 26-30, 2003, Institut Laue Langevin (ILL), Grenoble, France