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Comparison between ultrafiltration and nanofiltration hollow-fiber membranes for removal of natural organic matter : A pilot study

Increasing trends of natural organic matter (NOM) in surface water in Nordic countries may cause future problems for drinking water producers. Emerging membrane technology, such as ultrafiltration (UF) and nanofiltration (NF), has the potential to produce safe drinking water of good quality from sources with high organic concentrations. In the present pilot study, surface water from three sources

An Auction with Approximated Bidder Preferences - When an Auction has to be Quick

This paper presents a combinatorial auction which is of particular interest when short completion times are of importance. It is based on a method for approximating the bidders' preferences over two types of items when complementarity between the two may exist. The resulting approximated preference relation is shown to be complete and transitive at any given price vector. It is shown that an appro

Gaia reference frame amid quasar variability and proper motion patterns in the data

Context. Gaia’s very accurate astrometric measurements will allow the optical realisation of the International Celestial Reference System to be improved by a few orders of magnitude. Several sets of quasars are used to define a kinematically stable non-rotating reference frame with the barycentre of the solar system as its origin. Gaia will also observe a large number of galaxies. Although they ar

"Document of the Month" - a regular feature of the PRC History Group website

As of February 2014, a regular monthly contribution to the PRC History Group's website (prchistory.org/document-of-the-month) comprising the selection and reproduction of a unique archival record from the first decades of the People's Republic of China with added contextualizing, critical, and explanatory commentary highlighting the significance and importance of the document in question.

Crosstalk Mitigation for LTE-over-Copper in Downlink Direction

Radio-over-copper is a niche idea that has potential to become a cornerstone in the deployment of dense 5G networks. We address one of the remaining hurdles and present an architecture for transparent crosstalk mitigation in LTE-over-copper systems. By taking advantage of reference symbols present in the downlink LTE signals we propose two methods for estimating the copper channel. System performa

A comparison of Rosenbrock and ESDIRK methods combined with iterative solvers for unsteady compressible flows

In this article, we endeavour to find a fast solver for finite volume discretizations for compressible unsteady viscous flows. Thereby, we concentrate on comparing the efficiency of important classes of time integration schemes, namely time adaptive Rosenbrock, singly diagonally implicit (SDIRK) and explicit first stage singly diagonally implicit Runge-Kutta (ESDIRK) methods. To make the compariso

Cost estimation of electric traction machine and gearbox for a hybrid vehicle application

To increase the market share of hybrid vehicles within the automotive industry, it is necessary to minimize the cost increase related to the hybridization. In this context a methodology to estimate the cost of the electrical machine and transmission is developed. Insights on the selection of a cost effective electrical machine topology are provided and the benefits and disadvantages of different d

Prediction of Postoperative Pain from Electrical Pain Thresholds after Laparoscopic Cholecystectomy

OBJECTIVE:: Early postoperative pain correlates to persisting pain, psychosocial distress, and delayed mobilization with thromboembolic and infectious complications. Electrical pain thresholds (EPT) have shown promising results in being able to predict postoperative pain, but the results are conflicting. The aim of this study was to test whether EPT levels can be used to predict postoperative pain

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

A confocal optical microscope for detection of single impurities in a bulk crystal at cryogenic temperatures

A compact sample-scanning confocal optical microscope for detection of single impurities below the surface of a bulk crystal at cryogenic temperatures is described. The sample, lens, and scanners are mounted inside a helium bath cryostat and have a footprint of only 19 × 19 mm. Wide field imaging and confocal imaging using a Blu-ray lens immersed in liquid helium are demonstrated with excitation a

Dose management in conventional nuclear medicine imaging and PET

This review of the basic concepts of dose management in conventional nuclear medicine imaging and positron emission tomography focuses on methods for dose assessment, difficulties with image quality evaluation, need for clear image quality criteria and observer performance studies, studies on representative groups of patients contra individual patients, clinically applicable methods for dose reduc

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