Search results for "Tact"

Contact Estimation in Robot Interaction

2014

In the paper, safety issues are examined in a scenario in which a robot manipulator and a human perform the same task in the same workspace. During the task execution, the human should be able to physically interact with the robot, and in this case an estimation algorithm for both interaction forces and a contact point is proposed in order to guarantee safety conditions. The method, starting from residual joint torque estimation, allows both direct and adaptive computation of the contact point and force, based on a principle of equivalence of the contact forces. At the same time, all the unintended contacts must be avoided, and a suitable post-collision strategy is considered to move the r…

An Intracortical Implantable Brain-Computer Interface for Telemetric Real-Time Recording and Manipulation of Neuronal Circuits for Closed-Loop Interv…

2021

Recording and manipulating neuronal ensemble activity is a key requirement in advanced neuromodulatory and behavior studies. Devices capable of both recording and manipulating neuronal activity brain-computer interfaces (BCIs) should ideally operate un-tethered and allow chronic longitudinal manipulations in the freely moving animal. In this study, we designed a new intracortical BCI feasible of telemetric recording and stimulating local gray and white matter of visual neural circuit after irradiation exposure. To increase the translational reliance, we put forward a Göttingen minipig model. The animal was stereotactically irradiated at the level of the visual cortex upon defining the targe…

Men's doubles professional tennis on hard courts: Game structure and point ending characteristics

2019

Despite the great tradition and importance of the doubles game in professional tennis, no literature has analysed to date the performance of professional players. Therefore, the information on the characteristics of the game, or the tactics related to how the points are won in doubles play is scarce. The objective of this study has been to describe the basic characteristics of the structure of the doubles game, and to establish how the points finish in doubles professional tennis played on hard courts. Thirty-four ATP doubles matches played in 2018 were analysed, which included a total of 40 professional players. As per the game structure, the results showed that, in comparison to the singl…

Conditions for static friction between flat crystalline surfaces

2000

The conditions for the presence of static friction between two atomically smooth crystalline surfaces are investigated. Commensurate and incommensurate walls are studied. While two commensurate walls always pin at zero lateral force and positive pressures, incommensurate walls only pin if mobile atoms are present in the interface between the surfaces or if the solids are particularly soft. Surprisingly, static friction can be observed between rigid surfaces, either commensurate or incommensurate, that are separated by a freely diffusing fluid layer.

How do droplets on a surface depend on the system size?

2002

Abstract We investigate the thermodynamics of inhomogeneous polymer melts in the framework of a coarse grained off-lattice model. Properties of the liquid–vapour interface and the packing of the melt in contact with an attractive wall are considered. We employ Monte Carlo simulations in the grand canonical ensemble to determine excess free energies, the wetting temperature and the pre-wetting line, as well as the pre-wetting critical point. Having determined the wetting properties and the phase diagram of the model polymer, we perform canonical Monte Carlo simulations of small droplets on a surface. This allows us to study the dependence of droplet size on the wetting properties. It is foun…

Method for wettability characterization based on contact line pinning.

2010

We demonstrate an efficient and reliable method for wettability characterization by determining the contact angle theta which a liquid-vapor interface makes with a solid wall. The purpose is to overcome the difficulties, related to the curvature of the liquid-vapor interface, which make measurements of theta rather uncertain, especially on the micro- and nanoscale. The method employs a specially designed slitlike channel in contact with a reservoir whereby the wettability of one of the slit walls is to be examined whereas the other (auxiliary) wall is separated by half into a lyophilic and a lyophobic part so as to pin the incoming fluid and fix the one end of the liquid-vapor interface. In…

Heterogeneous nucleation at a wall near a wetting transition: a Monte Carlo test of the classical theory

2009

While for a slightly supersaturated vapor the free energy barrier ΔF(hom)(*), which needs to be overcome in a homogeneous nucleation event, may be extremely large, nucleation is typically much easier at the walls of the container in which the vapor is located. While no nucleation barrier exists if the walls are wet, for incomplete wetting of the walls, described via a nonzero contact angle Θ, classical theory predicts that nucleation happens through sphere-cap-shaped droplets attracted to the wall, and their formation energy is ΔF(het)(*) = ΔF(hom)(*)f(Θ), with f(Θ) = (1-cosΘ)(2)(2+cosΘ)/4. This prediction is tested through simulations for the simple cubic lattice gas model with nearest-nei…

Towards the origin of the shear force in near-field microscopy

2001

The shear force from a gold or a graphite sample acting on an approaching near-field optical probe is studied in detail. The adiabatic and dissipative contributions to the force are clearly distinguished by monitoring the amplitude as well as the phase of the tip vibration when the tip approaches the surfaces. We also take into account that not only the damping and the resonance frequency but also the mass of the system changes when the tip approaches the surface. The relative strength of the contributions to the force varies differently but characteristically with the distance of the two samples, starting at a much larger distance in the case of graphite. The adiabatic contribution is lar…

Nuorten vankien lapsuuden väkivaltakokemukset ja heidän vanhempiensa parisuhdeongelmat

1999

Cultural Differences in Personality and Aggressive Behavior in Intimate Partner Violence Offenders

2014

Intimate partner violence (IPV) is a ubiquitous and serious problem, the prevalence of which varies greatly around the world. Previous research shows that cultural factors interact with personality and that this interaction influences cognitions, attitudes, and behaviors that are related to personal and individual styles of resolving conflicts. In relation to this, the present study has three aims: comparing the self-reported IPV (physical, psychological and sexual) of English and Spanish offenders, comparing the Millon Clinical Multiaxial Inventory III (MCMI-III) scores of the two groups, and examining the association between country of origin, psychopathology, and IPV. The sample consist…