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A numerical study of disc brake wear dependence of rotor surface parameters

Airborne emissions from disc brakes adversely affect the air quality in urban areas of EU. The emissions come from the wear of the pads and rotors in disc brakes. The wear of disc brakes depends on the contact situation between the pads and rotors. During braking, secondary contact plateaus are created on both the pads and rotors contact surfaces. Literature reports numerical studies of the creati

Randomized trial of a left ventricular assist device as destination therapy versus guideline-directed medical therapy in patients with advanced heart failure. Rationale and design of the SWEdish evaluation of left Ventricular Assist Device (SweVAD) trial

AimsPatients with advanced heart failure (AdHF) who are ineligible for heart transplantation (HTx) can become candidates for treatment with a left ventricular assist device (LVAD) in some countries, but not others. This reflects the lack of a systematic analysis of the usefulness of LVAD systems in this context, and of their benefits, limitations and cost-effectiveness. The SWEdish evaluation of l

Porcine vs Bovine Bioprosthetic Aortic Valves: Long-Term Clinical Results

BackgroundPrevious studies have reported superior hemodynamic performance with bovine bioprosthetic aortic valves compared with porcine valves. However, conflicting results mean the long-term effect on survival is not well known. The aim of this study was to examine long-term survival, rate of aortic valve reoperations, and heart failure hospitalizations after surgical aortic valve replacement (AV

Empirically Driven Orthonormal Bases for Functional Data Analysis

In implementations of the functional data methods, the effect of the initial choice of an orthonormal basis has not been properly studied. Typically, several standard bases such as Fourier, wavelets, splines, etc. are considered to transform observed functional data and a choice is made without any formal criteria indicating which of the bases is preferable for the initial transformation of the da

Experimental Evaluation of Physical Breast Phantoms for 2D and 3D Breast X-Ray Imaging Techniques

Anthropomorphic phantoms are models of real or virtual parts of the body, organ or tissue, represented by tissue-equivalent materials that aim to provide a realistic and accurate representation of their anatomy and properties. The aim of this study is to evaluate experimentally the suitability of 3D printed materials in the production of both, physical breast phantoms and abnormalities, to be used

Could pin-on-disc tribometers be used to study the friction/wear performance of disc brake materials?

Pin-on-disc tribometers are used by the academia to study friction and wear of disc brake materials. It has been debated if a simplified set-up could reproduce the friction and wear behaviour of the disc brake assembly. The aim of this paper is to investigate and discuss this topic by comparing the friction surfaces with diverse microscopy techniques. Also, coefficients of friction, wear, and coll

The AIQ Meta-Testbed : Pragmatically Bridging Academic AI Testing and Industrial Q Needs

AI solutions seem to appear in any and all application domains. As AI becomes more pervasive, the importance of quality assurance increases. Unfortunately, there is no consensus on what artificial intelligence means and interpretations range from simple statistical analysis to sentient humanoid robots. On top of that, quality is a notoriously hard concept to pinpoint. What does this mean for AI qu

An Optimization Model for the Tradeoff Between Efficiency and Equity for Mobile Stroke Unit Placement

A mobile stroke unit (MSU) is an ambulance, where stroke patients can be diagnosed and treated. Recently, placement of MSUs has been studied focusing on either maximum population coverage or equal service for all patients, termed efficiency and equity, respectively. In this study, we propose an unconstrained optimization model for the placement of MSUs, designed to introduce a tradeoff between eff

Notes on a Z′

We reexamine anomaly free U(1) extensions of the standard model in the light of LHC Drell-Yan data, constraints from unitarity, and neutrino-electron scattering to put model-independent bounds in the parameter space populated by MZ′, the Z- Z′ mixing angle (αz ), and the extra U(1) effective gauge coupling (gx′ ). We propose a formalism where any model dependence is absorbed into these three param

Structural optimisation of diffusion driven degradation processes

In this article, we propose an optimisation framework that can contribute to the prevention of premature failure or damage to building structures and can thereby strengthen their longevity. We concentrate on structures that are contaminated by chemical substances and that have strong destructive effects on the material. The aim of this contribution is a mathematical algorithm that allows the optim

Low percentage of surgeons meet the minimum recommended unicompartmental knee arthroplasty usage thresholds : Analysis of 3037 Surgeons from Three National Joint Registries

Purpose: The reported usage of UKA is around 10% in the UK, Australian and New Zealand joint registries. However, some authors recommend that a higher UKA usage of 20%, or a minimum 12 UKA cases per year, would reduce revision rates. The purpose of this study was to analyze the percentage of surgeons performing the recommended thresholds in these 3 registries. Methods: Data from the UK, Australian