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MacKay-Neal (MN) and Hsu-Anastasopoulos (HA) low-density parity-check (LDPC) codes are known to achieve the capacity of memoryless binary-input symmetric-output channels under maximum likelihood (ML) decoding with bounded col- umn and row weight in their associated parity-check matrices. Recently, Kasai and Sakaniwa showed that spatially coupled (SC) versions of the MN and HA LDPC codes have belie

This paper presents the hardware implementation of a wavelet based event detector for cardiac pacemakers. A high level energy estimation flow was applied to evaluate energy efficiency of standard-cell based designs, over several CMOS technology generations, from 180 to 65 nm, operated in the sub-threshold domain. The simulation results indicate a 65 nm low-leakage high-threshold (LL-HVT) CMOS tech

It has previously been shown that ensembles of terminated protograph-based low-density parity-check (LDPC) convolutional codes have a typical minimum distance that grows linearly with block length and that they are capable of achieving capacity approaching iterative decoding thresholds on the binary erasure channel (BEC). In this paper, we review a recent result that the dramatic threshold improve

Intelligent transport information systems (TIS) are one of the most rapidly emerging applications of wireless vehicular communications using DSRC/WAVE technology. A core function in a TIS is the estimation of traffic density using beacons transmitted by individual vehicles, subsequently used for purposes such as traffic light control or incident detection. In this paper, we conduct an in-depth stu

In this paper we present a new class of MAC protocols for wireless LANs based on sharing of transmission intentions. We develop an example protocol implementation based on distributed, co-operative scheduling of data frames. Sched- ules are non-binding, requiring minimal negotiation between nodes. The protocol is implemented on top of standard 802.11 so that backwards compatibility with legacy nod

Concepts of cognitive radio are yet in an early stage of development. They aim at improving the efficiency of spectrum utilization by exploiting locally and temporally vacant parts of the spectrum. When hierarchical spectrum access is considered, secondary users are authorized to use spectrum white spaces on a non-interfering basis, where minimal impact on the primary systems has to be ensured. GF

We study the well known linear consensus algorithm by means of a LQ-type performance cost. We want to understand how the communication topology influences this algorithm. In order to do this, we recall the analogy between Markov Chains and electrical resistive networks. By exploiting this analogy, we are able to rewrite the performance cost as the average effective resistance on a suitable network

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 Populärvetenskaplig sammanfattning Hyaluronan (hyaluronsyra) är en högmolekylär polysackarid som förekommer i all biologisk vävnad i olika koncentrationer, med särskilt höga nivåer i bindväv. Den kan bildas av de flesta celltyper. På molekylär nivå föreligger den i form av ett nystan, har förmågan att binda stora mängder vatten, och har en uttalad pseudoplasticitet. HyaHyaluronan has been found in the eye in varying amounts and at different sites. It is involved in physiological and pathological processes, though many aspects of its bio-logi-cal functions are still unclear. We have studied the role of iris tissue in hyal-uro-nan production in the anterior segment of the eye, and its changes after trauma. After peripheral iridectomy or argon laser treatment, the

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