Partially supported by NSERC grant OGP-0121848 and European Community grant CHBGT-CT93-0244. The existence of an invariant surface in high-dimensional systems greatly influences the behavior in a neighborhood of the invariant surface. We prove theorems that predict the behavior of periodic orbits in the vicinity of an invariant surface on which the motion is conjugate to a Diophantine rotation ...

We report a new type of optical biosensor capable of differentiating between bulk and surface perturbations of the ambient refractive index as well as between specific and nonspecific binding of molecules on the sensor surface. The proposed detection scheme is based on tracking the shifts of hybridized bonding and antibonding optical modes in coupled optical microcavities (photonic molecules). ...

It is shown that landscape variability decreases the temperature in the surface layer when, through mesoscale flow, cool air intrudes over warm patches, lifting warm air and weakening the static stability of the upper part of the planetary boundary layer. This mechanism generates regions of upward vertical motion and a sizable amount of available potential energy and can make the environment of...

There is limited investigation of the interaction between motor unit recruitment and rate coding for modulating force during standing or responding to external perturbations. Fifty-seven motor units were recorded from the medial gastrocnemius muscle with intramuscular electrodes in response to external perturbations in standing. Anteriorly directed perturbations were generated by applying loads...

We compare the capillary levelling of a random surface perturbation on a thin polystyrene film with a theoretical study on the two-dimensional capillary-driven thin film equation. Using atomic force microscopy, we follow the time evolution of samples prepared with different initial perturbations of the free surface. In particular, we show that the surface profiles present long term self-similar...

Evidence of the existence of a transient surface tension between two miscible fluid phases is given. This is done by making use of a density matched free of gravity perturbations, binary liquid of isobutyric acid and water, which presents a miscibility gap and is studied by light scattering. The experiment is performed very near the critical point of the binary liquid, where the diffusion of ph...

We have proposed an improved method for calculating surface tension of liquid-vapour interface based on the thermodynamic route. This method combines the central difference scheme used in the test-area method and the Bennett weighting factor. This improved method shows faster convergence than the test area method as the weighting factor reduces the asymmetric bias of two perturbations. In addit...

We present a method for computing horizon maps from captured images of a bumpy surface. Horizon maps encode surface self-shadowing effects, and can be used with bump or normals maps to realistically render surfaces with small height perturbations. The method does not rely on complete surface reconstruction, and requires only eight captured images as input. In this paper we discuss how shadow in...

Balance recovery during walking requires complex sensory-motor integration. Mechanisms to avoid falls are active concomitantly with human locomotion motor patterns. It has been suggested that gait can be described by a set of motor modules (synergies), but little is known on the modularity of gait during recovery of balance due to unexpected slips. Our hypothesis was that muscular activation du...

The Directed Energy Deposition Additive Manufacturing (DED-AM) of SS316L was studied using in situ and operando synchrotron X-ray imaging to quantitively understand the effect processing parameters on melt-pool morphology surface quality. It found that roughness DED-AM builds can result from melt pool perturbations caused by changes flow build stage motion perturbations. Process maps are develo...