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Conditions for Carbonation of Silica Fume Concretes

This article outlines an experimental and numerical study on the pozzolanic interaction limits for carbonation of silica fume concretes. For this purpose cylinders of 8 types of High-Performance Concrete were cast. Carbonation and weight losses were studied parallel. An indirect method was used to measure carbonation; i.e. carbonation shrinkage was observed. The age of concrete at start of carbona

Increasing the Milling Accuracy for Industrial Robots Using a Piezo-Actuated High-Dynamic Micro Manipulator

The strong process forces arising during high-speed machining operations, combined with the limited stiffness of industrial robots, have hampered the usage of industrial robots in high-end milling tasks. However, since such manipulators may offer flexible and cost-effective machining solutions, a three-dimensional piezo-actuated compensation mechanism, which aims to compensate for the positioning

Evaluation of an Outdoor-to-In-Car Radio Channel with a Four-Antenna Handset and a User Phantom

Based on static outdoor channel measurements we evaluate the influence of a vehicle on the MIMO radio channel, from a base station antenna array, to a multiple antenna handset in the hand of a user placed inside a test car. The measurement scenario is chosen to mimic a 2.6 GHz (LTE) macro-cell urban or rural scenario with two locations and orientations of the car, one at an open parking lot with a

Gadodiamide injection for Enhancement of MRI in the CNS. Applications, dose, field and time dependence.

Popular Abstract in Swedish Magnetresonanstomografi (MRT) är en metod för framställning av bilder av kroppen och av sjukliga förändringar i kroppen. När metoden introducerades ansågs den utomordentligt goda inbyggda vävnadskontrasten vara tillräcklig för att särskilja olika sjukliga förändringar, speciellt i hjärnan. Det har emellertid visat sig att förmågan att upptäcka sjukliga förändringar är oAims of the study The aims of this study using Gadodiamide injection were to investigate: · Whether Gadodiamide injection was comparable to Gd-DTPA for the enhancement of CNS lesions. · The contrast effect at different field strengths. · The effective time-window for the enhancement of blood-brain barrier damage. · The relations between the concentration of contrast agent and enhancement in p

Phenotypic plasticity and local adaptation in tadpoles

Popular Abstract in Swedish Grodyngels anpassning till livsmiljön - om betydelsen av, och samspelet mellan, arv och miljö Bakgrund Naturen är variabel och föränderlig. Inom en arts utbredningsområde kan miljöförhållandena variera rumsligt, och vad som är en lyckad strategi med avseende på t.ex. reproduktion eller predatorundvikande på en plats är inte nödvändigtvis den optimala strategin på en aAmphibian larvae are plastic in many traits. Can plasticity buffer population divergence, so that local adaptation is more common in non-plastic traits? I argue that this may be the case for adaptive plastic responses. Tadpoles of Rana arvalis are shown to alter their tail depth plastically as a response to predation risk; this is a truly adaptive response. Tail depths in the field (population and

A conceptual study of OFDM-based multiple access schemes: Part 1 - Air interface requirements

The multimedia era has started. The migration of computer (packet oriented) and telephony (circuit switched) networks in combination with an explosive development of new services, creates a mass market for public broadband communication. There are no reasons foreseen why these kinds of services should not go mobile. Future customers will not treat a mobile access differently than a fixed access to