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It is today possible to manufacture so smooth surfaces that they can elastically conform totally to each other over the whole Hertzian contact area. For pure rolling lubrication such surfaces only need an oil film of molecular dimensions to get total separation. When the rolling motion is combined with sliding, the pressure fluctuations inside the Hertzian contact redistribute the oil and make met

The main component of the sex pheromone precursor in females of Macrodiprion nemoralis was identified as a threo-3,7,9-trimethyl-2-tridecanol isomer, approximately 800 pg per female, by gas chromatography-mass spectrometry. Comparison of mass spectrometric ion chromatograms showed that the natural compound in the female extract has the same retention time and mass spectrum as one of the two synthe

Patients with an implantable cardioverter defibrillator (ICD) have an ongoing risk of sudden incapacitation that might cause harm to others while driving a car. Driving restrictions vary across different countries in Europe. The most recent recommendations for driving of ICD patients in Europe were published in 1997 and focused mainly on patients implanted for secondary prevention. In recent years

Turbulent flow and heat transfer in a square-sectioned U-bend are investigated. Turbulence models with linear and non-linear expressions for the Reynolds stresses are used. The near wall turbulence is treated by the damping functions approach and a two-layer model with Wolfshtein's sub-layer treatment. The inlet conditions have a significant effect on the predictions. The results from the non-line

We consider the problem of determining for each pair of vertices of a directed acyclic graph (dag) on n vertices whether or not it has a unique lowest common ancestor, and if so, finding such an ancestor. We show that this problem can be solved in time O(n ω logn), where ω< 2.376 is the exponent of the fastest known algorithm for multiplication of two n×n matrices. We show also that the problem of

The electron transfer process in the interaction of a slow highlycharged ion with a metal surface has been studied employing amicrocapillary foil as a target. The combination of the target and avisible light spectroscopy allows us to directly evaluate the initial(n,ℓ) distributions of the first transferred electrons. It wasfound that observed lines were primarily attributed to Δn=1transitions with

We show that; one can count k-edge paths in an n-vertex graph and m-set k-packings on an n-element universe, respectively, in time (n k/2) and (n mk/2) up to a factor polynomial in n, k, and in: in polynomial space, the bounds hold if multiplied by 3(k/2) or 5(mk/2), respectively. These are implications of a more general result: given two set families on an n-element universe, one can count the di

This study explores nonverbal behaviors in the form of gestures and touch during elite handball matches. Based on a coding scheme, 616 post-shot periods following a goal, stemming from 18 matches, were analyzed. Results revealed that on average 2.77 nonverbal behaviors were displayed after scoring. Playoff matches resulted in a higher average of nonverbal behaviors than league matches. The more a

In this study, we examine how entrepreneurs differ in their modes of learning and whether variations in modes of learning have any influence on their possession of entrepreneurial knowledge that increase their ability to recognise and exploit new business opportunities. Based on statistical analysis of 291 entrepreneurs we find that a learning mode that favours exploration is positively associated

Tailbiting is an attractive method to terminate convolutional codes without reducing the code rate. Maximum-likelihood and exact a posteriori probability decoding of tailbiting codes implies, however, a large computational complexity. Therefore, suboptimal decoding methods are often used in practical coding schemes. It is shown that suboptimal decoding methods work better when the slope of the act

The Trelleborg project ran between 1999 and 2002. This article describes and analyzes the processes relating to institutionalization and social change, and their consequences, within the project. The research, funded by the Swedish National Institute of Public Health, was based on qualitative data collected during the project, including focused interviews with 12 key individuals, five focus group