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.

Supporting Context-Aware Collaboration in a Hospital: An Ethnographic Informed Design

Abstract: This paper reports the development of a context-aware messaging system to support the intensive and distributed nature which characterizes information management and collaboration in a hospital setting. Our design was based on a set of findings gathered during a workplace study conducted in a hospital. We identified that collaboration in the hospital is highly based on a set of contextual elements: (1) the location of people and devices, (2) the timing of messages to be delivered, (3) the role-oriented nature of the work and (4) the artifact-mediate nature of information gathering. Those elements were validated and their support analyzed with hospital’s staff through a session where scenarios of use where created, refined, and evaluated. The results of this study allowed us to inform the design process of a context-aware architecture to support collaboration in a hospital setting. The architecture allows for the implementation of applications that respond in accordance to the context surrounding the activities performed at the hospital, thus enhancing information exchange, collaboration, and ultimately, decision making. In particular, we focus our attention on a context-aware messaging system developed on top of this architecture, and which allows health care workers to exchange messages that depend, for their delivery, on the status of people, resources and/or devices.

Advances in Linear Modeling of Microwave Transistors

Abstract: Heterojunction field effect transistors (HFET) based on gallium nitride (AlGaN/GaN) and metal semiconductor field effect transistors (MESFETs) based on silicon carbide (SiC) are the preferred transistors for high-power amplifier circuit designs rather than MESFETs, high electron mobility transistors (HEMTs) and pseudomorphic HEMTs based on gallium arsenide (GaAs) or indium phosphide (InP) semiconductor technology. While AlGaN/GaN and SiC are good candidates for high-power applications, GaAs and InP semiconductor technologies are the preferred transistors in low-power, low-voltage, and low-noise applications [1].

Service discovery in mobile ad-hoc networks: better at the network layer?

Abstract: Cross-layer design approaches in wireless networks propose strong interactions between layers in the protocol stack, in order to obtain important performance gains. Mobile ad-hoc networks (MANETs) have special characteristics that make them suitable not only for cross-layer designs, but also for even tighter interactions of functions in different layers. With this in mind, we propose performing service discovery functions at the network layer, and not at the application layer, where they are traditionally found. We analyze the performance benefits that can be gained with this proposal, showing that services can be discovered faster and with less signaling traffic.

Measuring ephemeral gully erosion rates and topographical thresholds in an urban watershed using unmanned aerial systems and structure from motion photogrammetric techniques.

Abstract: Both rural and urban development can lead to accelerated gully erosion. Quantifying gully erosion is challenging in environments where gullies are rapidly repaired, and in urban areas where microtopographic complexity complicates the delineation of contributing areas. This study used unmanned aerial vehicles (UAVs) and Structure-from-Motion (SfM) photogrammetric techniques to quantify gully erosion in the Los Laureles Canyon watershed, a rapidly urbanizing watershed in Tijuana, Mexico. Following a storm event, the gully network extent was mapped using an orthomosaic (0.038 m pixel size); the local slope and watershed area contributing to each gully head were mapped with a Digital Surface Model (0.3 m pixel size). Gullies formed almost exclusively on unpaved roads which had erodible soils and concentrated flow. Management practices (e.g. road maintenance that fill gullies after large storms) contributed to total sediment production at the watershed scale. Sediment production from gully erosion was higher and threshold values of slope and drainage area for gully incision were lower than ephemeral gullies reported for agricultural settings. This indicates high vulnerability of unpaved roads to gully erosion which is consistent with high soil erodibility and low critical shear stress measured in the laboratory with a mini jet-erosion-test device. Future studies that evaluate effects of different soil types on gully erosion rates for unpaved roads, as well as those that model effects of management practices such as road paving and their impact on runoff, soil erosion, and sediment loads are needed to advance sediment management and planning in urban watersheds.