36 research outputs found
Total Roman {2}-domination in graphs
[EN] Given a graph G = (V, E), a function f: V -> {0, 1, 2} is a total Roman {2}-dominating function if every vertex v is an element of V for which f (v) = 0 satisfies that n-ary sumation (u)(is an element of N (v)) f (v) >= 2, where N (v) represents the open neighborhood of v, and every vertex x is an element of V for which f (x) >= 1 is adjacent to at least one vertex y is an element of V such that f (y) >= 1. The weight of the function f is defined as omega(f ) = n-ary sumation (v)(is an element of V) f (v). The total Roman {2}-domination number, denoted by gamma(t)({R2})(G), is the minimum weight among all total Roman {2}-dominating functions on G. In this article we introduce the concepts above and begin the study of its combinatorial and computational properties. For instance, we give several closed relationships between this parameter and other domination related parameters in graphs. In addition, we prove that the complexity of computing the value gamma(t)({R2})(G) is NP-hard, even when restricted to bipartite or chordal graphsCabrera García, S.; Cabrera Martinez, A.; Hernandez Mira, FA.; Yero, IG. (2021). Total Roman {2}-domination in graphs. Quaestiones Mathematicae. 44(3):411-444. https://doi.org/10.2989/16073606.2019.1695230S41144444
Simulated Basic Skills Training: Graduate Nursing Students Teaching Medical Students: A Work in Progress
For a number of years, Advanced Practice Nursing (APN) students have taught interested 1st year medical students to perform intramuscular injections prior to their participation in community flu clinics. When several 4th year medical students needed documentation of competency in intravenous (IV) cannulation prior to participating in an elective rotation at another institution, the Medical School\u27s Dean of Students called the Director of Interdisciplinary Partnerships in the Graduate School of Nursing to request assistance. In fact, all medical students need IV therapy training prior to graduation, not just those who seek out visiting clerkships at other medical schools. Integration of IV training into the Undergraduate Medical Education Surgery Clerkship Curriculum supports the clinical objectives of the Surgery Clerkship along with the developing use of simulation within in the medical school. This need led to the development of this interdisciplinary simulation education initiative.
Presented at the 2008 Society on Simulation in Healthcare Conference
Tactile exploration of virtual objects for blind and sighted people: the role of beta 1 EEG band in sensory substitution and supramodal mental mapping.
Two-dimensional simulation of the effects of grain boundaries on the C-V characteristics of P+N polysilicon diodes
International audienc
Tactile exploration of virtual objects for blind and sighted people: the role of beta 1 EEG band in sensory substitution and supramodal mental mapping
The neural correlates of exploration and cognitive mapping in blindness remain elusive. The role of visuo-spatial pathways in blind vs. sighted subjects is still under debate. In this preliminary study, we investigate, as a possible estimation of the activity in the visuo-spatial pathways, the EEG patterns of blind and blindfolded-sighted subjects during the active tactile construction of cognitive maps from virtual objects compared with rest and passive tactile stimulation. Ten blind and ten matched, blindfolded-sighted subjects participated in the study. Events were defined as moments when the finger was only stimulated (passive stimulation) or the contour of a virtual object was touched (during active exploration). Event-related spectral power and coherence perturbations were evaluated within the beta 1 band (14–18 Hz). They were then related to a subjective cognitive-load estimation required by the explorations [namely, perceived levels of difficulty (PLD)]. We found complementary cues for sensory substitution and spatial processing in both groups: both blind and sighted subjects showed, while exploring, late power decreases and early power increases, potentially associated with motor programming and touch, respectively. The latter involved occipital areas only for blind subjects (long-term plasticity) and only during active exploration, thus supporting tactile-to-visual sensory substitution. In both groups, coherences emerged among the fronto-central, centro-parietal, and occipito-temporal derivations associated with visuo-spatial processing. This seems in accordance with mental map construction involving spatial processing, sensory-motor processing, and working memory. The observed involvement of the occipital regions suggests that a substitution process also occurs in sighted subjects. Only during explorations did coherence correlate positively with PLD for both groups and in derivations, which can be related to visuo-spatial processing, supporting the existence of supramodal spatial processing independently of vision capabilities
Validation of the VBLaST peg transfer task: a first step toward an alternate training standard
International audienceBackground: The FLS trainer lacks objective and automated assessments of laparoscopic performance and requires a large supply of relatively expensive consumables. Virtual reality simulation has a great potential as a training and assessment tool of laparoscopic skills and can overcome some limitations of the FLS trainer. This study was carried out to assess the value of our Virtual Basic Laparoscopic Surgical Trainer (VBLaST©) in the peg transfer task compared to the FLS trainer and its ability to differentiate performance between novice, intermediate and expert groups. Methods: Thirty subjects were divided into three groups: novices (PGY1-2, n = 10), intermediates (PGY3-4, n=10), and experts (PGY5, surgical fellows and attendings, n = 10). All subjects performed ten trials of the peg transfer task on each simulator. Assessment of laparoscopic performance was based on FLS scoring while a questionnaire was used for subjective evaluation. Results: The performance scores in the two simulators were correlated, though subjects performed significantly better in the FLS trainer. Experts performed better than novices only on the FLS trainer while no significant differences were observed between the other groups. Moreover, a significant learning effect was found on both trainers, with a greater improvement of performance on the VBLaST©. Finally, 82.6% of the subjects preferred the FLS over the VBLaST© for surgical training which could be attributed to the novelty of the VR technology and existing deficiencies of the user interface for the VBLaST©. Conclusion: This study demonstrated that the VBLaST© reproduced faithfully some aspects of the FLS peg transfer task (such as color, size and shape of the peg board, etc.) while other aspects require additional development. Future improvement of the user interface and haptic feedback will enhance the value of the system as an alternative to the FLS as the standard training tool for laparoscopic surgery skills
The enerMENA Meteorological Network - Solar Radiation Measurements in the MENA Region
Solar irradiance and ancillary meteorological data are needed for solar resource assessment. Accurate measurements are required for comparison and adjustment of long‐term satellite data. Furthermore, reliable irradiance measurements are needed to validate Direct Normal Irradiance (DNI) forecasting methods. Starting in 2010, ten meteorological stations have been installed in the Middle East and Northern Africa (MENA) within the enerMENA projec