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Mobile communication systems are becoming increasingly heterogeneous as new standards emerge. Currently, the wireless operators are upgrading their existing 3G networks such as UMTS and CDMA2000 to different kinds of 4G networks such as LTE and WiMAX. We can witness these days that mobile terminals are having the capability to access many of these wireless network types. The networks are very diff

Purpose – The rapid proliferation of mobile context aware applications has resulted in an increased research interest towards developing specialized context data management strategies for mobile entities. The purpose of this paper is to aim to develop a new way to model mobile entities and manage their contexts accordingly. Design/methodology/approach – This paper proposes the concept of “Mobile

The hygroscopic growth of the atmospheric aerosol is a critical parameter for quantifying the anthropogenic radiative forcing. Until now, there has been a lack of long term measurements due to limitations in instrumental techniques. In this work, for the first time the seasonal variation of the hygroscopic properties of a continental background aerosol has been described, based on more than two ye

Cloud condensation nuclei counter (CCNC) measurements performed at 14 locations around the world within the European Integrated project on Aerosol Cloud Climate and Air Quality interactions (EUCAARI) framework have been analysed and discussed with respect to the cloud condensation nuclei (CCN) activation and hygroscopic properties of the atmospheric aerosol. The annual mean ratio of activated clou

Context-aware computing applications dynamically change their behaviors based on the context data and services provided by multiple physical spaces in the real world, such as persons, shops, homes and offices. In this paper, we propose a generic context gateway framework to manage these heterogeneous physical spaces of context sources. The framework forms a key enabling component of a scalable con

Beryllium 10 concentrations (Be-10(con)) were measured at annual resolution from varved sediment cores of Lakes Tiefer See (TSK) and Czechowskie (JC) for the period 1983-2009 (similar to solar cycles 22 and 23). Calibrating the Be-10(con) time-series against complementing proxy records from the same archive as well as local precipitation and neutron monitor data, reflecting solar forced changes in

Context: The questions of how many individuals and how much time to use for a single testing task are critical in software verification and validation. In software review and usability evaluation contexts, positive effects of using multiple individuals for a task have been found, but software testing has not been studied from this viewpoint. Objective: We study how adding individuals and imposing

Generalized frequency division multiplexing is a non-orthogonal, digital multicarrier transmission scheme with attractive features that address the requirements of emerging applications of wireless communications systems in areas like cognitive radio and machine-to-machine communication. In this paper, first a linear system description is obtained for the transmitter by ordering data in a time-fre

Landscape patchiness creates aerodynamic transition zones that affect the exchange of nutrients and pollutants between the atmosphere and vegetation. Using an artificially-generated NaCl aerosol (mass-versus-particle-size distribution with aerodynamic mean particle diameter 1.6 mu m; geometric standard deviation 1.9), we investigated the forest-edge effect on aerosol deposition within a model oak

Palaeoceanographic changes over the last 6800 years are documented in a diatom record from core MD05-2908 from the southern Okinawa Trough. Changes in diatom components are used to reflect variations in the strength of the Kuroshio Current and the influence of coastal waters, and these changes are compared with records of the East Asian summer monsoon, which exerts an important influence on region

It is important to evaluate each step in radiocarbon analysis to ensure that the whole process is as efficient and accurate as possible. Aerosol filter samples contain a myriad of carbonaceous compounds with varying resistance to oxidation. Complete combustion of the sample is thus of great importance to ensure that the graphitized sample is representative of the original filter sample. We have ev

Codes constructed from connected spatially coupled low-density parity-check code (SC-LDPCC) chains are proposed and analyzed. It is demonstrated that connecting coupled chains results in improved iterative decoding performance. The constructed protograph ensembles have better iterative decoding thresholds compared to an individual SC-LDPCC chain and require less computational complexity per bit wh

This discussion paper, by a Working Group of INTIMATE (Integration of ice-core, marine and terrestrial records) and the Subcommision on Quaternary Stratigraphy (SQS) of the International Commission on Stratigraphy (ICS), considers the prospects for a formal subdivision of the Holocene Series/Epoch. Although previous attempts to subdivide the Holocene have proved inconclusive, recent developments i

The origin of two large peaks in the atmospheric radiocarbon ((14)C) concentration at AD 774/5 and 993/4 is still debated. There is consensus, however, that these features can only be explained by an increase in the atmospheric (14)C production rate due to an extraterrestrial event. Here we provide evidence that these peaks were most likely produced by extreme solar events, based on several new an

Very high levels of ambient particulate matter (PM) are frequently encountered in the north of Italy and air quality limits are regularly exceeded. To obtain quantitative information on the pollution sources and to gain understanding of the dynamics of pollution episodes in this populated area PM10 and/or PM2.5 samples were collected daily at nine urban to regional sites distributed over the centr

A detailed three-dimensional regional chemical transport model (Particulate Matter Comprehensive Air Quality Model with Extensions, PMCAMx) was applied over Europe, focusing on the formation and chemical transformation of organic matter. Three periods representative of different seasons were simulated, corresponding to intensive field campaigns. An extensive set of AMS measurements was used to eva

In May 2008 the EUCAARI-LONGREX aircraft field campaign was conducted within the EUCAARI intensive observational period. The campaign aimed at studying the distribution and evolution of air mass properties on a continental scale. Airborne aerosol and trace gas measurements were performed aboard the German DLR Falcon 20 and the British FAAM B.4e-146 aircraft. This paper outlines the meteorological