Extensive Air Shower Radio Detection: Recent Results and Outlook

A prototype system for detecting radio pulses associated with extensive cosmic ray air showers is described. Sensitivity is compared with that in previous experiments, and lessons are noted for future studies.Comment: 17 pages, LaTeX, 7 figures, invited talk presented by J. Rosner at RADHEP-2000 Conference, UCLA, Nov. 16-18, 2000, Proceedings published by AIP. Some figures and text changed; one reference update

The French ?Earned Income Supplement? (RSA) and back-to-work incentives

RMI, API, unemployment, means-tested benefits, back-to-work incentives.

Determinants of Agricultural Disaster Payments in the Southeastern U.S.: County Level Analysis

Using county level data we study if weather and climate variables or variables used as proxies for rent-seeking behavior determine disaster payment in the Southeast. We do not find evidence of rent-seeking but find that, in addition to weather, long term climate variables affect disaster payments.Farm Management, Risk and Uncertainty,

Climate Effects on Rainfall Index Insurance Purchase Decisions

Rainfall Index insurance is a pilot insurance product offered to producers of hay and pasture in 9 states. This analysis examines the expected payoff of the RI insurance for bi-monthly periods based on rainfall shortage probabilities in alternative climate phases. Differences in expected returns indicate that selection of ENSO-specific optimal intervals may result in higher returns than those based on pooled rainfall series.rainfall insurance, ENSO, expected indemnity, Production Economics, Risk and Uncertainty,

Phonon Engineering of the Specific Heat of Twisted Bilayer Graphene: The Role of the Out-of-Plane Phonon Modes

We investigated theoretically the specific heat of graphene, bilayer graphene and twisted bilayer graphene taking into account the exact phonon dispersion and density of states for each polarization branch. It is shown that contrary to a conventional believe the dispersion of the out-of-plane acoustic phonons - referred to as ZA phonons - deviates strongly from a parabolic law starting from the frequencies as low as ~100 1/cm. This leads to the frequency-dependent ZA phonon density of states and the breakdown of the linear dependence of the specific heat on temperature T. We established that ZA phonons determine the specific heat for T<200 K while contributions from both in-plane and out-of-plane acoustic phonons are dominant for 200 K < T < 500 K. In the high-temperature limit, T>1000 K, the optical and acoustic phonons contribute approximately equally to the specific heat. The Debye temperature for graphene and twisted bilayer graphene was calculated to be around ~1861 - 1864 K. Our results suggest that the thermodynamic properties of materials such as bilayer graphene can be controlled at the atomic scale by rotation of the sp2-carbon planes.Comment: 25 pages, 5 figure

Design and simulation of a multi-function MEMS sensor for health and usage monitoring.

Health and usage monitoring as a technique for online test, diagnosis or prognosis of structures and systems has evolved as a key technology for future critical systems. The technology, often referred to as HUMS is usually based around sensors that must be more reliable than the system or structure they are monitoring. This paper proposes a fault tolerant sensor architecture and demonstrates the feasibility of realising this architecture through the design of a dual mode humidity/pressure MEMS sensor with an integrated temperature function. The sensor has a simple structure, good linearity and sensitivity, and the potential for implementation of built-in-self-test features. We also propose a re-configurable sensor network based on the multi-functional sensor concept that supports both normal operational and fail safe modes. The architecture has the potential to significantly increase system reliability and supports a reduction in the number of sensors required in future HUMS devices. The technique has potential in a wide range of applications, especially within wireless sensor networks

A prototype system for detecting the radio-frequency pulse associated with cosmic ray air showers

The development of a system to detect the radio-frequency (RF) pulse associated with extensive air showers of cosmic rays is described. This work was performed at the CASA/MIA array in Utah, with the intention of designing equipment that can be used in conjunction with the Auger Giant Array. A small subset of data (less than 40 out of a total of 600 hours of running time), taken under low-noise conditions, permitted upper limits to be placed on the rate for pulses accompanying showers of energies around $10^{17}$ eV.Comment: 53 pages, LaTeX, 19 figures, published in Nuclear Instruments and Methods. Revised version; some references update