Ensenada Center for Scientific Research and Higher Education

About: Ensenada Center for Scientific Research and Higher Education is a facility organization based out in Ensenada, Mexico. It is known for research contribution in the topics: Population & Nonlinear system. The organization has 1934 authors who have published 3733 publications receiving 63115 citations.

Jokebox: Coordinating Shared Encounters in Public Spaces

Abstract: Eye contact is crucial to shared encounters in public spaces. However, most urban technologies that aim to foster social interaction' attention towards the device rather than to those with whom the encounter is shared. We present the design and evaluation of the Jokebox, a lightweight technology that requires two passers-by to coordinate actions to hear a joke. In three in the wild studies at different locations we found that our design supported micro-level coordination in a consistent manner: by encouraging people to make eye contact and by using audible jokes, users engaged in interactions that often led to further conversation and laughter. We describe how opportunities for macro-level coordination were key to the success of the installation, but varied by context. Finally, we present design implications for considering both the micro and macro levels of social coordination.

Observations of internal wave packets propagating along-shelf in northern Monterey Bay

Abstract: Internal waves of depression were observed propagating along-shelf and into northern Monterey Bay, California (CA) on the inner shelf. These waves had amplitudes approximately equal to the thermocline depth (∼4 m), and were unstable to shear and mix the thermocline. Isopycnal gradient spectra showed that the wave packets lead to an elevated mean dissipation rate of ɛ = 2.63 × 10−5 m3 s−2 for up to 2 hours after wave passage. The proximity to the surface created strong surface convergences that can actively transport buoyant material, such as plankton, back into the bay. The wave packets were observed regularly over the upwelling season across multiple years suggesting they may have large effects on the documented spatial variation of phytoplankton and larvae on the inner shelf. The timing of the waves suggests they are not formed by tides interacting with bathymetry, but are generated by buoyant plume propagation.

Nonlinear H∞-Output Regulation of a Nonminimum Phase Servomechanism With Backlash

Abstract: Nonlinear H ∞ control synthesis is extended to an output regulation problem for a servomechanism with backlash. The problem in question is to design a feedback controller so as to obtain the closed-loop system in which all trajectories are bounded and the load of the driver is regulated to a desired position while also attenuating the influence of external disturbances. Provided the servomotor position is the only measurement available for feedback, the proposed extension is far from trivial because of non-minimum phase properties of the system. Performance issues of the nonlinear H ∞ -output regulator constructed are illustrated in an experimental study.