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Binary assignments of amino acids from pattern conservation

We have developed a simple optimization procedure for assigning binary values to amino acids. The binary values are determined by a maximization of the degree of pattern conservation in groups of closely related protein sequences. The maximization is carried out at fixed composition. For compositions approximately corresponding to an equipartition of the residues, the optimal encoding is found to

Functional differentiation of antiporter-like polypeptides in complex I; a site-directed mutagenesis study of residues conserved in MrpA and NuoL but Not in MrpD, NuoM, and NuoN

It has long been known that the three largest subunits in the membrane domain (NuoL, NuoM and NuoN) of complex I are homologous to each other, as well as to two subunits (MrpA and MrpD) from a Na+ /H+ antiporter, Mrp. MrpA and NuoL are more similar to each other and the same is true for MrpD and NuoN. This suggests a functional differentiation which was proven experimentally in a deletion strain m

Monte Carlo study of the phase structure of compact polymer chains

We study the phase behavior of single homopolymers in a simple hydrophobic/hydrophilic off-lattice model with sequence independent local interactions. The specific heat is, not unexpectedly, found to exhibit a pronounced peak well below the collapse temperature, signalling a possible low-temperature phase transition. The system size dependence at this maximum is investigated both with and without

The one triangle three parallelograms sampling strategy and its application in shape regression

The purpose of this paper is threefold. Firstly, the paper introduces the One Triangle Three Parallelograms (OTTP) sampling strategy, which can be viewed as a way to index pixels from a given shape and image. Secondly, a framework for cascaded shape regression, including the OTTP sampling, is presented. In short, this framework involves binary pixel tests for appearance features combined with shap

Tight linear convergence rate bounds for Douglas-Rachford splitting and ADMM

Douglas-Rachford splitting and the alternating direction method of multipliers (ADMM) can be used to solve convex optimization problems that consist of a sum of two functions. Convergence rate estimates for these algorithms have received much attention lately. In particular, linear convergence rates have been shown by several authors under various assumptions. One such set of assumptions is strong

Enhanced impact Echo frequency peak by time domain summation of signals with different source receiver spacing

The Impact Echo method can be used to measure the thickness of concrete plate like structures. Measurements are based on the identification of a clear thickness resonance frequency which can be difficult in very thick or highly attenuative plates. In this study the detectability of the measured resonant frequency is enhanced by time domain summation of signals with different source receiver spacin

A high diet quality based on dietary recommendations is not associated with lower incidence of type 2 diabetes in the malmö diet and cancer cohort

A high diet quality index based on Swedish nutrition recommendations has previously been associated with reduced risk of cardiovascular disease and mortality in the Malmö Diet and Cancer (MDC) cohort. The aim of the present study was to investigate whether this diet quality index was associated with the risk for type 2 diabetes. Of 26,868 participants (44-74 years) in the MDC cohort study, 3838 ty

Reciprocity Calibration for Massive MIMO: Proposal, Modeling and Validation

This paper presents a mutual coupling based calibration method for time-division-duplex massive MIMO systems, which enables downlink precoding based on uplink channel estimates. The entire calibration procedure is carried out solely at the base station (BS) side by sounding all BS antenna pairs. An Expectation-Maximization (EM) algorithm is derived, which processes the measured channels in order t

Standardization and Innovation within the Green Buildings field: Insights from Europe

A research project was conducted by the two PhD students Markus Arnez Wegelius and Philip Hedestad from the Standardisation Research Centre, within the Institute of Economic Research at Lund University, Sweden, and with the supervision of Mr. Daniele Gerundino, Strategic Adviser to the Secretary-General (ISO). The project was sponsored by ISO (The International Organization for Standardization), N

A New Design Method for Broadband Microphone Arrays for Speech Input in Automobiles

A new design method for broadband microphone arrays is presented. Using sequences of calibration signals, the method is able to design finite-impulse response (FIR) filters with specific performance. The method can control and adjust the speech distortion, noise suppression, and echo cancellation directly. It turns out that a significantly shorter filter length can be applied to achieve better ove

Optimal FIR Subband Beamforming for Speech Enhancement in Multipath Environments

The letter provides an analysis of optimal finite-impulse response subband beamforming for speech enhancement in multipath environments. A modification of the direct-path standard Wiener formulation is shown to give nearly optimal performance when it comes to signal-to-noise-plus-interference ratio, by including coherent multipath propagation in the criterion.

Complex-valued independent component analysis for online blind speech extraction

This paper presents a theoretical analysis of acertain criterion for complex-valued independent componentanalysis (ICA) with a focus on blind speech extraction (BSE) of aspatio–temporally nonstationary speech source. In the paper, theproposed criteria denoted KSICA is related to the well-known FastICAmethod with the Kurtosis contrast function. The proposedmethod is shown to share the important fix

Calibration Errors of Uniform Linear Sensor Arrays for DOA Estimation: an Analysis with SRP-PHAT

This article presents an analysis of the sensitivity of geometrical sensor errors in acoustic source localization using the well-established SRP-PHAT method. The array in this analysis is a uniform linear array and the intended source is human speech in the far field. Two major results are presented: inner-sensor geometrical errors in the linear array produce smaller localization errors than corre

A Calibrated Subband Beamforming Algorithm for Speech Enhancement

The paper proposes a new calibrated adaptive frequency domain beamformer for speech enhancement. The beamformer is based on the principle of a soft constraint formed from calibration data, rather than precalculated from free-field assumptions. The benefit is that the real room acoustical properties are taken into account. The proposed algorithm continuously estimates the spatial information for ea

Limits in FIR Subband Beamforming for Spatially Spread Nearfield Sources

This paper analyses optimal subband beamforming performance mainly aimed at speech enhancement and acoustic echo suppression for personal communication devices, personal computers and wireless cellular telephones. The focus is on theoretical limits of finite impulse response (FIR) beamformers for spatially spread sources in the array near-field. Performance of the Wiener solution is compared to th

Spatial Filter Bank Design for Speech Enhancement Beamforming Applications

In this paper, a new spatial filter bank design method for speech enhancement beamforming applications is presented. The aim of this design is to construct a set of different filter banks that would include the constraint of signal passage at one position (and closing in other positions corresponding to known disturbing sources). By performing the directional opening towards the desired location i