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Exposure to cosmic radiation of British Airways flying crew on ultralonghaul routes.

Bagshaw, M; Irvine, D; Davies, D M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /07/1996 EN
Relevância na Pesquisa
15.72%
British Airways has carried out radiation monitoring in Concorde for more than 20 years and has used a heuristic model based on data quoted by the National Aeronautics and Space Administration (NASA) to model radiation exposure in all longhaul fleets. From these data it has been calculated that no flight deck crew would exceed the control level of 6 mSv/y currently under consideration by regulatory authorities, which is three tenths of the occupational dose limit of 20 mSv/y recommended by the International Commission on Radiological Protection (ICRP). The model suggested that less than 4% of cabin crew based in Tokyo flying only between London and Japan could reach or exceed the 6 mSv/y level, based on a predicted effective dose rate of 7 microSv/h. To validate this calculation a sampling measurement programme was carried out on nine round trips flown by a Boeing 747-400 between London and Tokyo. The radiation field was measured with dosimeters used for routine personal monitoring (thermoluminescence dosimeters (TLDs) and polyallydiglycol carbonate neutron dosimeters). The limitations of the methodology are acknowledged, but the results indicate that the effective dose rate was 6 microSv/h which is consistent with the predicted effective dose rate of 7 microSv/h. This result...

Low cost indoor ultrasonic positioning implemented in FPGA

Sánchez, Alberto; Elvira Díaz, Santiago; Castro, Ángel de; González-de-Rivera, Guillermo; Ribalda Delgado, Ricardo; Garrido, Javier
Fonte: Institute of Electrical and Electronics Engineers Publicador: Institute of Electrical and Electronics Engineers
Tipo: conferenceObject; bookPart
ENG
Relevância na Pesquisa
15.83%
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. A. Sánchez, S. Elvira, Á. de Castro, G. Gonzalez-de-Rivera, R. Ribalda, J. Garrido, "Low cost indoor ultrasonic positioning implemented in FPGA", 35th Annual Conference of IEEEIndustrial Electronics, 2009. IECON '09, Porto (Portugal), 2009, pp. 2709 - 2714; This paper presents a low cost indoor ultrasonic-based positioning system. This system allows the mobile nodes of a Wireless Sensor Network to know their location using radiofrequency and ultrasonics. To achieve this goal, a matrix of transmitting anchor points is installed whereas the mobile nodes receive these transmitted signals and estimate the time-of-flight of the ultrasonic signals. Using two time-of-flight measurements and trilateration equations, the location of the mobile nodes can be inferred in a 2-D space.

Towards 2015 : Spending for Indonesia's Development, Shaping the Prospects of a Middle-Income Country

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Policy Note; Economic & Sector Work
ENGLISH; EN_US
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15.81%
This report discusses the future of Indonesia's public expenditures as it enters the 21st century. It contributes to the discussion on Indonesia's spending priorities for the years ahead. These choices will impact the lives of Indonesians, and their opportunities to grow richer and receive better services. The report will contribute to Indonesia s next five-year plan, the RPJM, which will take effect in January 2010. Indonesia has been one of the most successful countries in reducing its debt-to-GDP ratio. Since 1999, when debt levels reached over 90 percent of GDP, Indonesia has reduced its debt levels to just above 30 percent of GDP by the end of 2008. Education spending increased from 11 percent of total government spending in 2001 to 15 percent in 2008. Chapter 1 discusses public spending from 2001 to 2009, including discretionary spending, key sectors, subsidies and decentralization. Chapter 2 analyzes Indonesia's economy in the current (2009) economic downturn. Indonesia is in a position of relative economic strength despite the impact of the global financial crisis. This is largely thanks to its broad-based growth that has avoided over-reliance on exports. The share of output that Indonesia exports is the smallest of the major Southeast Asian economies. Chapter 3 presents the future of Indonesia's fiscal growth to 2015. Notwithstanding noteworthy achievements over the past decade...

Jamaica : Poverty and Social Impacts of Fiscal Reforms

World Bank
Fonte: Washington, DC Publicador: Washington, DC
Tipo: Economic & Sector Work :: Other Poverty Study; Economic & Sector Work
ENGLISH; EN_US
Relevância na Pesquisa
25.81%
This Poverty and Social Impact Analysis (PSIA) explores the distributional effects of a package of fiscal reforms initiated by the Government of Jamaica and supported by the World Bank under the programmatic fiscal sustainability Development Policy Loan (DPL) series. The DPL series supports improved budget and debt management in order to reduce the debt overhang and create additional fiscal space for productive public spending, including social expenditures. The PSIA discusses the poverty and distributional impacts of the prior actions supported under the DPL, with a particular focus on two reform actions likely to have the most significant impacts: (1) tax reform and (2) public sector reform, focusing on rationalization of public bodies. The report offers both quantitative and qualitative assessments of the potential poverty and distributional effects of these policy changes. The report is structured as follows: section two analyzes the expected impact of changes in tax policy; section three investigates the potential impacts of public bodies' rationalization...

Birds of a Feather: Neanderthal Exploitation of Raptors and Corvids

Finlayson, Clive; Brown, Kimberly; Blasco, Ruth; Rosell, Jordi; Negro, Juan José; Bortolotti, Gary R.; Finlayson, Geraldine; Sánchez Marco, Antonio; Giles Pacheco, Francisco; Rodríguez Vidal, Joaquín; Carrión, José S.; Fa, Darren A.; Rodríguez Llan
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 17/09/2012 EN
Relevância na Pesquisa
15.72%
The hypothesis that Neanderthals exploited birds for the use of their feathers or claws as personal ornaments in symbolic behaviour is revolutionary as it assigns unprecedented cognitive abilities to these hominins. This inference, however, is based on modest faunal samples and thus may not represent a regular or systematic behaviour. Here we address this issue by looking for evidence of such behaviour across a large temporal and geographical framework. Our analyses try to answer four main questions: 1) does a Neanderthal to raptor-corvid connection exist at a large scale, thus avoiding associations that might be regarded as local in space or time?; 2) did Middle (associated with Neanderthals) and Upper Palaeolithic (associated with modern humans) sites contain a greater range of these species than Late Pleistocene paleontological sites?; 3) is there a taphonomic association between Neanderthals and corvids-raptors at Middle Palaeolithic sites on Gibraltar, specifically Gorham's, Vanguard and Ibex Caves? and; 4) was the extraction of wing feathers a local phenomenon exclusive to the Neanderthals at these sites or was it a geographically wider phenomenon?. We compiled a database of 1699 Pleistocene Palearctic sites based on fossil bird sites. We also compiled a taphonomical database from the Middle Palaeolithic assemblages of Gibraltar. We establish a clear...

Smart flight control surfaces with microelectromechanical systems

Lyshevski, Sergey
Fonte: IEEE Publicador: IEEE
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
35.96%
Pitch, roll, and yaw moments can be developed by deflecting and changing the geometry of control surfaces. In this paper, smart flight control surfaces are designed using multi-node microelectromechanical systems (MEMS) to displace control surfaces and change the surface geometry. These MEMS augment translational motion microstructures (actuators-sensors), controlling/signal processing integrated circuits (ICs), radiating energy devices and antennas. The desired pitch, roll, and yaw moments are produced, drag can be reduced, and unsteady aerodynamic flows are controlled by smart flight control surfaces. That is, we achieve aerodynamic moment and active flow control capabilities. The major objective here is to report fundamental and applied research in design of smart flight control surfaces with MEMS-based actuator-sensor-IC arrays controlled by hierarchical distributed systems. We demonstrate the feasibility and effectiveness of the application of smart flight control surfaces for coordinated longitudinal and lateral vehicle control.; Copyright 2002 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists...

Legal challenges relating to the commercial use of outer space, with specific reference to space tourism

Ferreira-Snyman,A
Fonte: PER: Potchefstroomse Elektroniese Regsblad Publicador: PER: Potchefstroomse Elektroniese Regsblad
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
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55.91%
Since the launch of the first artificial satellite, Sputnik 1 in 1957, the outer space arena has evolved to include non-state entities, which are becoming serious participants in outer space activities themselves, including venturing into the space tourism market. Although space tourism is still in its infancy, it is estimated that the number of space tourists will substantially increase within the next few years. As space tourist activities increase, accidents will inevitably occur, which will give rise to legal questions relating to the duty of states to rescue space tourists in distress, and the liability for damages. This contribution points out that the current outer space treaty regime, which focuses on the use of outer space by states, is to a large extent outdated and that it cannot adequately deal with the unique legal challenges presented by the rapidly developing space tourism industry. This situation is exacerbated by the fact that the outer space legal framework is very fragmented -consisting of treaties, UN principles and guidelines, regional regulations and intergovernmental agreements, as well as national guidelines and legislation. In order to ensure that space tourism is indeed to the benefit of all mankind, it is imperative that clear international legal rules relating to space tourism be formulated...