Neutrino Astronomy and Cosmic Rays Spectroscopy at Horizons

A new air-showering physics may rise in next years at horizon, offering at different angles and altitudes a fine tuned filtered Cosmic Rays astrophysics and an upward Neutrino induced air-showering astronomy. Most of this opportunity arises because of neutrino masses, their mixing and the consequent replenishment of rarest tau flavor during its flight in Space. Horizontal air atmosphere act as a filter for High energy Cosmic Rays (CR) and as a beam dump for Ultra High Energy (UHE) neutrinos and a powerfull amplifier for its tau decay in air by its wide showering areas. Earth sharp shadows plays the role of a huge detector volume for UHE neutrino and a noise-free screen for upcoming EeVs tau air-showers (as well PeVs anti-neutrino electron air interactions). Projects for Tau Airshowers are growing at the top of a mountains or at the edge of a cliff. ASHRA in Hawaii and CRNTN in Utah are tracking fluorescence lights, while other novel projects on Crown array detectors on mountains, on balloons and satellites are elaborated for Cherenkov lights. AUGER, facing the Ande edges, ARGO located within a deep valley are testing inclined showers; MILAGRO (and MILAGRITO) may be triggered by horizontal up-going muon bundles from the Earth edges; HIRES and AUGER UHECR detectors, linking twin array telescopes along their axis may test horizontal Cerenkov blazing photons. MAGIC (Hess, Veritas) and Shalon Telescopes may act already like a detector for few PeVs and Glashow resonance neutrino events; MAGIC pointing downward to terrestrial ground acts as a massive tens of km^3 detector, making it the most sensitive dedicated neutrino telescope. MAGIC facing the sea edges must reveal mirrored downward UHECR Air-showers Cherenkov flashes. Magic-crown systems may lead to tens km^3, neutrino detectors.Comment: 24 pages, 24 figures, Conference NO-VE, Venice, 09-02-200

Natural resources and conflict in Africa: what do the data show?

The empirical relationship between natural resources and conflict in Africa is not very well understood. Using a novel geocoded dataset we are able to construct a quasi-natural experiment to explore the causal effects of oilfield and mineral discoveries on intra-state armed conflict in Africa at the grid-cell level corresponding to a spatial resolution of 0.5 x 0.5 degrees latitude and longitude. We find no evidence of resource discoveries triggering conflict after controlling for property rights institutions, past discoveries, grid-cell and year fixed effects, grid-cell specific trends, and country-year fixed effects. Resource discoveries are associated with improved local living standards and increased political patronage both of which reduce conflict. We observe little or no heterogeneity in the relationship across resource types, discovery size, distance to discovery and borders, and institutions. The relationship remains unchanged at higher grid-cell resolution, and regional and national levels

A Survey of Positioning Systems Using Visible LED Lights

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.As Global Positioning System (GPS) cannot provide satisfying performance in indoor environments, indoor positioning technology, which utilizes indoor wireless signals instead of GPS signals, has grown rapidly in recent years. Meanwhile, visible light communication (VLC) using light devices such as light emitting diodes (LEDs) has been deemed to be a promising candidate in the heterogeneous wireless networks that may collaborate with radio frequencies (RF) wireless networks. In particular, light-fidelity has a great potential for deployment in future indoor environments because of its high throughput and security advantages. This paper provides a comprehensive study of a novel positioning technology based on visible white LED lights, which has attracted much attention from both academia and industry. The essential characteristics and principles of this system are deeply discussed, and relevant positioning algorithms and designs are classified and elaborated. This paper undertakes a thorough investigation into current LED-based indoor positioning systems and compares their performance through many aspects, such as test environment, accuracy, and cost. It presents indoor hybrid positioning systems among VLC and other systems (e.g., inertial sensors and RF systems). We also review and classify outdoor VLC positioning applications for the first time. Finally, this paper surveys major advances as well as open issues, challenges, and future research directions in VLC positioning systems.Peer reviewe

The electrification of spacecraft

Physical and applied aspects of the electrification of space vehicles and natural celestial objects are discussed, the factors resulting in electrification of spacecraft are analyzed, and methods of investigating various phenomena associated with this electrification and ways of protecting spacecraft against the influence of static electricity are described. The booklet is intended for the general reader interested in present day questions of space technology

NASA Thesaurus supplement: A four part cumulative supplement to the 1988 edition of the NASA Thesaurus (supplement 3)

The four-part cumulative supplement to the 1988 edition of the NASA Thesaurus includes the Hierarchical Listing (Part 1), Access Vocabulary (Part 2), Definitions (Part 3), and Changes (Part 4). The semiannual supplement gives complete hierarchies and accepted upper/lowercase forms for new terms