MIMO precoding for filter bank modulation systems based on PSVD

In this paper we consider the design of a linearly precoded MIMO transceiver based on filter bank (FB) modulation for transmission over broadband frequency selective fading channels. The modulation FB is capable of lowering the channel dispersion at sub-channel level. Nevertheless, the sub-channels experience some level of inter-symbol interference. Therefore, the pre-coder and the equalizer are designed exploiting the polynomial singular value decomposition (PSVD). In particular, we consider two types of FB system. The first system deploys maximal frequency confined pulses and it is referred to as filtered multitone (FMT) modulation, while the second uses maximal time confined pulses with rectangular impulse response, i.e., it corresponds to the conventional orthogonal frequency division multiplexing (OFDM) system. We compare the performance of the considered systems in terms of capacity over typical WLAN channels, showing that PSVD precoding with FMT can outperform the performance of precoded OFDM in the two-bytwo antenna case especially for moderate to low SNRs

Evaluating the Effects of Farm Programs: Results from Propensity Score Matching

The paper applies a non-parametric propensity score matching approach to evaluate the effects of two types of farm programs (agri-environment (AE) programs and the less favoured area (LFA) scheme) on input use and farm output of individual farms in Germany. The analysis reveals a positive and significant treatment effect of the LFA scheme for farm sales and the area under cultivation. Participants in AE schemes are found to significantly increase the area under cultivation (in particular grassland), resulting in a decrease of livestock densities. Furthermore, participation in AE programs significantly reduced the purchase of farm chemicals (fertilizer, pesticide). We also find substantial differences in the treatment effect between individual farms (heterogeneous treatment effects). Farms which can generate the largest benefit from the program are most likely to participate.evaluation, farm programs, propensity score matching, Agricultural and Food Policy,

Dynamical symmetry breaking in transport through molecules

We analyze the interplay between vibrational and electronic degrees of freedom in charge transport across a molecular single-electron transistor. We focus on the wide class of molecules which possess quasi-degenerate vibrational eigenstates, while no degeneracy occurs for their anionic configuration. We show that the combined effect of a thermal environment and coupling to leads, involving tunneling events charging and discharging the molecule, leads to a dynamical symmetry breaking where quasi-degenerate eigenstates acquire different occupations. This imbalance gives rise to a characteristic asymmetry of the current versus an applied gate voltage.Comment: 4 pages, 2 figures, revised final published versio

Farm Structure and the Effects of Agri-Environmental Programs: Results from a Matching Analysis for European Countries

This paper extends previous research (Pufahl and Weiss, 2009) and applies a semi-parametric propensity score matching approach to evaluate the effects of agrienvironment (AE) programs on input use and farm output of individual farms in eight Member States of the European Union. We find substantial differences in treatment effects between countries. The analysis reveals significant effects of AE participation on production (Germany, France) and farm profits (France, Ireland, United Kingdom). AE participation sporadically reduces the intensity of land use as measured by the purchase of farm chemicals (fertilizer, pesticide) and grazing livestock densities. We also find differences in the treatment effect among farms with different farm size (heterogeneous treatment effects).evaluation, agri-environment programs, propensity score matching, Germany, Italy, Spain, France, Portugal, United Kingdom, The Netherlands, EU-15, Agribusiness, Agricultural and Food Policy,

PLC for the smart grid: state-of-the-art and challenges

This paper aims to review systems and applications for power line communications (PLC) in the context of the smart grid. We discuss the main applications and summarise state-of-the-art PLC systems and standards. We report efforts and challenges in channel and noise modelling, as well as in state-of-the-art transmission technology approaches

Nakajima-Zwanzig versus time-convolutionless master equation for the non-Markovian dynamics of a two-level system

We consider the exact reduced dynamics of a two-level system coupled to a bosonic reservoir, further obtaining the exact time-convolutionless and Nakajima-Zwanzig non-Markovian equations of motion. The considered system includes the damped and undamped Jaynes-Cummings model. The result is obtained by exploiting an expression of quantum maps in terms of matrices and a simple relation between the time evolution map and time-convolutionless generator as well as Nakajima-Zwanzig memory kernel. This non-perturbative treatment shows that each operator contribution in Lindblad form appearing in the exact time-convolutionless master equation is multiplied by a different time dependent function. Similarly, in the Nakajima-Zwanzig master equation each such contribution is convoluted with a different memory kernel. It appears that depending on the state of the environment the operator structures of the two set of equations of motion can exhibit important differences.Comment: 12 pages, no figure

Initial results on an MMSE precoding and equalisation approach to MIMO PLC channels

This paper addresses some initial experiments using polynomial matrix decompositions to construct MMSE precoders and equalisers for MIMO power line communications (PLC) channels. The proposed scheme is based on a Wiener formulation based on polynomial matrices, and recent results to design and implement such systems with polynomial matrix tools. Applied to the MIMO PLC channel, the strong spectral dynamics of the PLC system together with the long impulse responses contained in the MIMO system result in problems, such that diagonlisation and spectral majorisation is mostly achieved in bands of high energy, while low-energy bands can resist any diagonalisation efforts. We introduce the subband approach in order to deal with this problem. A representative example using a simulated MIMO PLC channel is presented

EXPRESSION OF A FUNCTIONAL CHIMERIC lg-MHC CLASS II PROTEIN

composed of the a- and ß-chains of the MHC class I1 I-E molecule fused to antibody V regions derived from anti-human CD4 mAb MT310. Expression vectors were constructed containing the functional, rearranged gene segments coding for the V region domains of the antibody H and L chains in place of the first domains of the complete structural genes of the I-E a- and ß-chains, respectively. Celltsr ansfected with both hybrid genes expressed a stable protein product on the cell surface. The chimeric molecule exhibited the idiotype of the antibody MT310 as shown by binding to the anti-idiotypic mAb 20-46. A protein of the anticipated molecular mass was immunoprecipitated witha nti-mouse IgG antiserum. Furthermore, human soluble CD4 did bind to thetr ansfected cell line, demonstrating that the chimeric protein possessed the binding capacity of the original mAb. Thus, the hybrid molecule retained: 1) the properties of a MHC class I1 protein with regardt o correct chain assembly and transport to the cell surface: as well as 2) the Ag binding capacity of the antibody genes used. Thgee neration of hybrid MHC class I1 molecules with highly specific, non-MHC-restricted bindingc apacities will be useful for studying MHC class 11-mediated effector functions such as selection of the T cell repertoire in thymus of transgenic mice

Pair-wise decoherence in coupled spin qubit networks

Experiments involving phase coherent dynamics of networks of spins, such as echo experiments, will only work if decoherence can be suppressed. We show here, by analyzing the particular example of a crystalline network of Fe8 molecules, that most decoherence typically comes from pairwise interactions (particularly dipolar interactions) between the spins, which cause `correlated errors'. However at very low T these are strongly suppressed. These results have important implications for the design of quantum information processing systems using electronic spins.Comment: 4 pages, 4 figures. Final PRL versio