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Kamchatka is one of the world's most active volcanic regions and has hosted many explosive eruptions during the Holocene. These eruptions had the potential to disperse tephra over wide areas, forming time-synchronous markers wherever those tephras are found. Recent research in Kamchatka has begun to focus on the geochemical analysis of individual glass shards in order to characterise tephra layers

Inter-comparison of results from two kinds of aerosol systems in the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on a Instrument Container) passenger aircraft based observatory, operating during intercontinental flights at 9-12 km altitude, is presented. Aerosol from the lowermost stratosphere (LMS), the extra-tropical upper troposphere (UT) and the tropical mid t

The 2008 Kasatochi volcanic eruption emitted 1.5-2.5 Tg SO2 into the upper troposphere and lower stratosphere. Parts of the main volcanic plume (gases and particles) reached central Europe a week after the eruption and were detected there by the CARIBIC (Civil Aircraft for Regular investigation of the Atmosphere based on an Instrument Container) flying observatory. The plume was also observed by t

Ensembles of (J,K)-regular low-density parity-check convolutional (LDPCC) codes are known to be asymptotically good, in the sense that the minimum free distance grows linearly with the constraint length. In this paper, we use a protograph-based analysis of terminated LDPCC codes to obtain an upper bound on the free distance growth rate of ensembles of periodically time-varying LDPCC codes. This bo

SimSWE is a library of components for modeling and simulation of software engineering processes. It consists of a generic, implementation independent description of the components and a reference implementation using the MATLAB® / Simulink® environment. By providing ready-to-use building blocks for typical functionality, the library should facilitate and ease the use of simulation to analyze softw

Achieving QoS-based broadband wireless access means a lot for the people living in the information age. WiMAX has evolved now into a stage that we can say it can meet this demand. From among the various fields to study in this domain, call admission and scheduling are the strongest tools in our hand to ensure QoS. On the other side, exploiting mesh topology is a good technique to increase the netw

Many of the next generation of global climate models will include aerosol schemes which explicitly simulate the microphysical processes that determine the particle size distribution. These models enable aerosol optical properties and cloud condensation nuclei (CCN) concentrations to be determined by fundamental aerosol processes, which should lead to a more physically based simulation of aerosol d

Simulations of climate over the Last Millennium (850-1850 CE) have been incorporated into the third phase of the Paleoclimate Modelling Intercomparison Project (PMIP3). The drivers of climate over this period are chiefly orbital, solar, volcanic, changes in land use/land cover and some variation in greenhouse gas levels. While some of these effects can be easily defined, the reconstructions of sol

Abstract in UndeterminedThe MPEG Reconfigurable Video Codingworking group is developing a new library-based pro-cess for building the reference codecs of future MPEGstandards, which is based on dataflow and uses an actorlanguage called Cal. The paper presents a code genera-tor producing RTL targeting FPGAs for Cal, outlinesits structure, and demonstrates its performance on anMPEG-4 Simple Profile

The ash cloud of the Eyjafjallajokull (also referred to as: Eyjafjalla (e.g. Schumann et al., 2011), Eyjafjoll or Eyjafjoll (e.g. Ansmann et al., 2010)) volcano on Iceland caused closure of large parts of European airspace in April and May 2010. For the validation and improvement of the European volcanic ash forecast models several research flights were performed. Also the CARIBIC (Civil Aircraft

Volcanic eruptions contribute to climate variability, but quantifying these contributions has been limited by inconsistencies in the timing of atmospheric volcanic aerosol loading determined from ice cores and subsequent cooling from climate proxies such as tree rings. Here we resolve these inconsistencies and show that large eruptions in the tropics and high latitudes were primary drivers of inte

Vehicular traffic density is a key factor in determining the behaviour of radio overlapping and thus impacts performance of data and safety message communication in Vehicular Ad hoc Networks (VANETs). In this paper, we propose a novel density model for urban traffic systems and employ this model for the purpose of spatial-temporal analysis of radio overlapping. To model traffic density, we conside

Families of asymptotically regular LDPC block code ensembles can be formed by terminating (J, K)-regular protograph-based LDPC convolutional codes. By varying the termination length, we obtain a large selection of LDPC block code ensembles with varying code rates, minimum distance that grows linearly with block length, and capacity approaching iterative decoding thresholds, despite the fact that t

A threshold analysis of terminated braided block codes (BBCs) is presented for the binary erasure channel. Protograph based BBCs (PG-BBCs) are considered, which can be derived by lifting the Tanner graph of a tightly braided block code. They can be interpreted as GLDPC convolutional codes that are structured in a particular way. It is shown that the terminated PG-BBCs have better thresholds than t

Window decoding schedules are very attractive for message passing decoding of spatially coupled LDPC codes. They take advantage of the inherent convolutional code structure and allow continuous transmission with low decoding latency and complexity. In this paper we show that the decoding complexity can be further reduced if suitable message passing schedules are applied within the decoding window.

In this paper we investigate the frame-error correcting performance of two newly developed, non-binary belief propagation based, soft-in/soft-out decoding algorithms when decoding Reed-Solomon codes. We present results for the AWGN channel indicating that non-binary belief propagation can come close to the performance of the binary adaptive Belief-Propagation algorithm or even slightly better when

Addressing the challenges of extreme scale computing re- quires holistic design of new programming models and sys- tems that support those models. This paper discusses the Angstrom processor, which is designed to support a new Self-aware Computing (SEEC) model. In SEEC, applications explicitly state goals, while other systems components provide actions that the SEEC runtime system can use to meet

Recent advances of body networks enable the acquisition of personal context from various kinds of body sensors. As a result, how to build a platform to properly manage personal context becomes a problem. In order to address this issue, we design and implement a mobile physical space gateway (MPSG) which is a generic context management framework in mobile spaces. This framework includes three layer

In this paper we address the problem of generating efficient software implementations for a large class of dataflow programs that is characterized by highly data-dependent behavior and which is therefore in general not amenable to compile-time scheduling. Previous work on implementing dataflow programs has emphasized classes of stream processing algorithms that exhibit sufficiently regular behavio

This paper develops a control integration methodology that can be used to balance competing performance objectives. The target application for the method is blood glucose management for diabetic patients. The true system model is uncertain and changes over time. Multiple controllers have been designed with competing performance objectives in mind. In the proposed method, on-line predictors are use