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How can a smart cyber-physical system validate its run-time adaptation actions before and after executing them?

Time has come for engineered systems to behave smartly. Towards this end, they need (i) to collect data directly from real life processes, (ii) to build situation awareness, (iii) to reason about their operational states, (iv) to determine the best servicing objectives, (v) to plan their run-time adaptation, and (vi) to provide dependable operations/services even under dynamically changing circums

A Multi-criteria Polymer Gears Design Optimisation Procedure

An open challenge is the reliable dimensioning of polymer gears due to the lack of accurate data on the fatigue strength of polymer materials, and the complex relations between geometric and operating parameters. The national standards (BS 6168:1987, JIS B 1759:2013) and the guidelines of the German engineering association VDI 2736 are available for the calculation of polymer gears. In most cases,

Application of knowledge management system to injection mold design and manufacturing in small enterprises

This paper present the solutions that a company introduced to tackle the problems that it faced during the engineering design and manufacturing of plastic injection molds. The company took an approach of introducing knowledge management system for risk reduction and avoiding problems that had already been recognized in the past. Based on preliminary analysis, knowledge management system model has

Towards validation of smart cyber-physical systems

Conventional technical system is designed with all details in the product development phase. Conditions of operation and modes of behaviour are known and validated before the product is launched to the market. This deterministic way of thinking is built into regulations procedures and it is requested at validation when safety is an issue. The existing way of validation that is based on predictive

Knowledge management support in the engineering change process

Knowledge management (KM) in the engineering change management process is crucial for any manufacturing enterprise. Increasing complexity triggers an increasing demand for systematic management of information and knowledge. KM is of strategic importance to a successful management of an enterprise, especially when the key staff changes. Systematically gathered, analyzed and interpreted professional

Accelerated lifetime testing of reinforced polymer gears

The main advantages of polymer gears in comparison to metal gears are low manufacturing costs for mass production, vibration damping and no need for lubricant. In the literature and guidelines, the allowable gear endurance limits for bending and contact stresses are mainly given for polyamides (PA) and polyacetals (POM). The large number of suitable polymer gear materials is available, but the sta

Perioperative Alcohol and Smoking Cessation Intervention : Impact on Other Lifestyles

Objective: Cigarette smoking and alcohol drinking are preventable risk factors in surgery. It is unknown whether intervening on these two risk factors also have an effect on other lifestyles. Therefore, the primary aim of this study was to compare the effect of an intensive alcohol and smoking cessation intervention on other lifestyles (malnutrition, obesity, and physical inactivity) with treatmen

3D Strain Field Evolution and Failure Mechanisms in Anisotropic Paperboard

Background: Experimental analyses of the 3D strain field evolution during loading allows for better understanding of deformation and failure mechanisms at the meso- and microscale in different materials. In order to understand the auxetic behaviour and delamination process in paperboard materials during tensile deformation, it is essential to study the out-of-plane component of the strain tensor t

Assessment of lifestyle factors helps to identify liver fibrosis due to non-alcoholic fatty liver disease in obesity

Only some individuals with obesity develop liver fibrosis due to non-alcoholic fatty liver disease (NAFLD-fibrosis). We determined whether detailed assessment of lifestyle factors in addition to physical, biochemical and genetic factors helps in identification of these patients. A total of 100 patients with obesity (mean BMI 40.0 ± 0.6 kg/m2 ) referred for bariatric surgery at the Helsinki Univers

Lilian Andersson (1937-2019) in memoriam

Minnesord över en förgrundsfigur inom den svenska sexarbetarrörelsen. Andersson var en av medgrundarna till Sexualpolitisk Front, Nordens första sexarbetarorganisation. Under hela sitt vuxna liv arbetade hon för att sexsäljares situation i samhället skulle förbättras, och 2017 tilldelades hon Jasminepriset, föreningen Rose Alliances pris för arbete mot våld mot sexarbetare,

A short-term comparison of expander prosthesis and DIEP flap in breast reconstructions : A prospective randomized study

Background: There is yet no clear consensus on which method is preferable in secondary breast reconstructions, prosthesis, or autologous tissue. Methods: In this first prospective randomized study, 29 women underwent reconstruction with expander prosthesis (EP) and 44 with deep inferior epigastric perforator (DIEP) flap. Inclusion started in 2012 and ended in 2018. Demographic data, complications,

The PNPLA3-I148M Variant Confers an Antiatherogenic Lipid Profile in Insulin-resistant Patients

CONTEXT: The I148M (rs738409-G) variant in PNPLA3 increases liver fat content but may be protective against cardiovascular disease. Insulin resistance (IR) amplifies the effect of PNPLA3-I148M on liver fat. OBJECTIVE: To study whether PNPLA3-I148M confers an antihyperlipidemic effect in insulin-resistant patients. DESIGN: Cross-sectional study comparing the impact of PNPLA3-I148M on plasma lipids

Different teeth profile shapes of polymer gears and comparison of their performance

This article presents a lifespan testing analysis of polymer gears manufactured by cutting. Compared to injection molding, machine cutting provides higher accuracy of gear geometry. Two different tooth flank geometries were tested; i.e. involute and S-gears. In theory, S-gears have several advantages over involute gears due to the convex/concave contact between the matching flanks. The theoretical

Detecting COVID-19 infection hotspots in England using large-scale self-reported data from a mobile application : a prospective, observational study

Background: As many countries seek to slow the spread of COVID-19 without reimposing national restrictions, it has become important to track the disease at a local level to identify areas in need of targeted intervention. Methods: In this prospective, observational study, we did modelling using longitudinal, self-reported data from users of the COVID Symptom Study app in England between March 24,