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We analyze the convergence behavior of iteratively decoded coupled LDPC codes from a complexity point of view. It can be observed that the thresholds of coupled regular LDPC codes approach capacity as the node degrees and the number L of coupled blocks tend to infinity. The absence of degree two variable nodes in these capacity achieving ensembles implies for any fixed L a doubly exponential decre
We investigate the CCN activity of freshly emitted biomass burning particles and their hygroscopic growth at a relative humidity (RH) of 85%. The particles were produced in the Mainz combustion laboratory by controlled burning of various wood types. The water uptake at sub- and supersaturations is parameterized by the hygroscopicity parameter, κ (c.f. Petters and Kreidenweis, 2007). For the wood b
Road safety is one of the most important emerging applications envisioned for Vehicular Ad hoc Networks (VANETs). Generally, such applications involve the broadcast of safety messages, consisting of beacons transmitting vehicles' state (e.g. position and velocity) with a regular period, as well as emergency messages warning about unexpected critical events. From the perspective of safety, the appl
Popular Abstract in Swedish Balansen mellan våra energibehov och den energi som konsumeras är ej längre i jämvikt. Därför är jakten på alternativa energikällor nödvändig. Hållbara energikällor erbjuder ett bra alternativ till fossilbränslen. Bland många typer av hållbara energikällor erbjuder solenergi möjligheten för mer energi än dagens konsumtion. Solceller är de smarta verktyg som omvandlar ljThe balance between our demands of energy and the energy we are consuming is not in equilibrium anymore. Therefore, the search for other energy resources is indispensable. Sustainable energy sources offer the alternative to the fossil fuels. Within many types of sustainable energy sources, solar energy offers more than the total global energy consumption. Solar cells are the smart conversion tools
The climate in the Arctic is changing faster than anywhere else on earth. Poorly understood feedback processes relating to Arctic clouds and aerosol-cloud interactions contribute to a poor understanding of the present changes in the Arctic climate system, and also to a large spread in projections of future climate in the Arctic. The problem is exacerbated by the paucity of research-quality observa
Shibanqiao Reservoir (0.24 km(2)) and Xiaohe Reservoir (0.28 km(2)) have catchments of 6.00 km(2) and 22.69 km(2), respectively. They essentially represent "strongly eroded" (Shibanqiao) and "mildly eroded" (Xiaohe) regions in Guizhou Plateau, southwestern China. Sediment cores were retrieved from the two reservoirs and soils were also sampled from their catchments. Mineral magnetic measurements w
Lake sediments and peat deposits from two basins on Nightingale Island (37 degrees S), in the Tristan da Cunha archipelago, South Atlantic, have been analyzed. The studies were focused on the time period 16.2-10.0 cal ka BP, determined by 36 C-14 dates from the two sequences. A wide variety of proxies were used, including pollen and diatom analyzes, biogenic silica content, C and N analyzes, stabl
Message passing schedules that reduce the decoding complexity of terminated LDPC convolutional code ensembles are analyzed. Considering the AWGN channel, various schedules are compared by means of density evolution. The results of the analysis together with computer simulations for some (3,6)-regular codes confirm that sliding window decoding is an attractive practical solution for low-latency and
Abstract: We report on a 1000 year long oxygen isotope record in sediments of the eastern Norwegian Sea which, we argue, represents the temperature and transport of warm Atlantic waters entering the Nordic Sea basin via the North Atlantic Drift and the large-scale Meridional Overturning Circulation. The single-sample resolution of the record is 2.5-10 years and age control is provided by Pb-210 an
We used the Aerosol Dynamics gas- and particle-phase chemistry model for laboratory CHAMber studies (ADCHAM) to simulate the contribution of BVOC plant emissions to the observed new particle formation during photooxidation experiments performed in the Julich Plant-Atmosphere Chamber and to evaluate how well smog chamber experiments can mimic the atmospheric conditions during new particle formation
Unique measurements of vertical size-resolved aerosol particle concentrations, trace gas concentrations and meteorological data were obtained during the Arctic Summer Cloud Ocean Study (ASCOS, www.ascos.se), an International Polar Year project aimed at establishing the processes responsible for formation and evolution of low-level clouds over the high Arctic summer pack ice. The experiment was con
We present palaeomagnetic secular variation and relative palaeointensity estimates from multiple sediment cores recovered from a varved lake sediment sequence in Kalksjon, a lake in central west Sweden. Alternating field demagnetization of discrete samples reveals natural remanent magnetizations dominated by a stable, single component. Magnetic grain size indicators-which include Day plots and fir
The average consensus algorithm is a distributed procedure which allows a network of agents to agree on the average of a set of initial values. The computation occurs through local exchange of information only, namely the information exchange takes place only between agents which are neighbors with respect to a graph representing the system communication architecture. Several performance metrics h
Aerosol-cloud interactions constitute a major uncertainty in future climate predictions. This study combines 10 years of ground-based aerosol particle measurements from two Nordic background stations (Vavihill and Hyytiala) with MODIS (Moderate Resolution Imaging Spectroradiometer) satellite data of convective clouds. The merged data are used to examine how aerosols affect cloud droplet sizes and
The awareness of the significance of the Southern Ocean in the Earth's climate system has become increasingly obvious. The deglacial atmospheric CO2 rise during warming periods in Antarctica has been attributed to CO2 ventilation from the deep ocean caused by enhanced upwelling around the Antarctic Divergence. It has been hypothesized that, more intense Southern Hemisphere westerly winds aligned w
The solar proxy Be-10, measured in natural archives, has previously been assumed to lag solar activity by 1-2 yr. This reflects its residence time in the stratosphere where its main source lies. This study, based on a 30-yr global model simulation of the atmospheric transport of Be-10, shows that the stratospheric fraction of production varies significantly with the phase of solar activity. This l
Context-aware computing is an exciting paradigm in which applications perceive and react to changing environments in an unattended manner. To enable behavioral adaptation, a context-aware application must dynamically acquire context data from different operating spaces in the real world, such as homes, shops and persons. Motivated by the sheer number and diversity of operating spaces, we propose a
Lake sediments from the Magherus, Valley in the lowlands of northern Transylvania provide new evidence of paleoenvironmental development in Romania during the Late Glacial. The studied sediments were deposited as a result of the damming of a small river valley following a series of mass wasting events that occurred during the deglaciation period. A continuous sedimentary sequence belonging to the
