684 research outputs found

    Sensor networks for social networks

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    Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2006.Includes bibliographical references (p. 51-55).This thesis outlines the development of software that makes use of Bayesian belief networks and signal processing techniques to make meaningful inferences about real-world phenomena using data obtained from sensor networks. The effectiveness of the software is validated by applying it to the problem of detecting face-to-face social interactions between groups of people, given data readings from sensors that record light, temperature, acceleration, sound, and proximity. This application represents a novel method for social network construction which is potentially more accurate and less intrusive than traditional methods, but also more meaningful than newer methods that analyze digitally mediated communication.by Michael P. Farry.M.Eng

    Factores que inciden en la aplicación por las instituciones educativas de las medidas que establece la ley 29719 o ley antibullying : estudio de caso en instituciones educativas de los distritos de Independencia, San Luis y Miraflores : período de estudio enero a diciembre 2014

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    Nuestra investigación pretendió comprender los factores que influyen en la implementación de la ley 29719 en las instituciones educativas de gestión pública y gestión privada a fin de poder plantear medidas que favorezcan a una óptima implementación. En ese sentido, lo que hallamos en nuestro estudio es que la ley 29719 y su reglamento, a cuatro años de haber sido promulgada, tiene un bajo grado de implementación lo que, en principio se explica, por el poco o nulo conocimiento de la norma que tienen los principales agentes ejecutores; es decir directores, docentes y psicólogos, padres de familia y estudiantes. Ahora, cabe destacar que encontramos diferencias entre los colegios nacionales y particulares dado que en el caso de los segundos, se evidencia mayor conocimiento de la ley 29719 en comparación con los primeros. Tal es así que los colegios particulares han llegado a elaborar un plan de convivencia e implementado algunas medidas preventivas, pero principalmente basándose en su experiencia y criterios personales antes que en lo señalado por la ley. Mientras que en el caso de los colegios nacionales, a pesar que han emprendido algunas acciones preventivas contra el bullying y a favor de la mejora de la convivencia escolar, evidencian desconocimiento de la ley 29719. Por otro lado, las instituciones educativas estudiadas coinciden en la preocupación que muestran por el problema del bullying y la convivencia escolar, considerando estos dos temas como importantes y reconociendo en forma explícita la necesidad de atenderlos. Sin embargo, todavía no han implementado la mayor parte de las medidas que señala la ley 29719. Esto también se debe a la poca incidencia de casos identificados como bullying en sus instituciones, que no han motivado ampliar y continuar las acciones adoptadas al respecto. Por su parte el MINEDU, no ha promocionado suficientemente la ley 29719 y tampoco ha realizado supervisiones al respecto, lo que si ha llegado a hacer la Defensoría del Pueblo. Tal situación se debe, a que tienen observaciones significativas respecto a la aplicabilidad de algunas medidas que se señala en la norma y que no tenían una línea base del problema del bullying que le sirviera de punto de partida y comparación. Por ello, se propusieron hacer un diagnóstico y algunos proyectos pilotos de capacitación. En ese contexto, tanto el MINEDU como los directores, docentes y psicólogos tienen una confianza limitada respecto a que la ley 29719 se aplique cabalmente, ya que consideran deben cambiar algunas condiciones para que lo señalado en dicha norma se llegue a cumplir. Finalmente, es importante señalar que la presente investigación es un estudio cualitativo donde la forma de investigación establecida fue el Estudio de Caso y como técnicas para el recojo de información se utilizó la Entrevista Semiestructurada y la Revisión Documental. En ese sentido, nuestras fuentes de información estuvieron representadas por un funcionario público del Ministerio de Educación y la Defensoría del Pueblo, director, psicólogos, docentes, padres de familia y estudiantes de cuatro instituciones educativas de Miraflores, Independencia y San Luis públicas y privadas. Además de informes y oficios del MINEDU y la Defensoría del Pueblo sobre la aplicación de la ley 29719.Tesi

    A System to Monitor Cognitive Workload in Naturalistic High-Motion Environments

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    Across many careers, individuals face alternating periods of high and low attention and cognitive workload can impair cognitive function and undermine job performance. We have designed and are developing an unobtrusive system to Monitor, Extract, and Decode Indicators of Cognitive Workload (MEDIC) in naturalistic, high-motion environments. MEDIC is designed to warn individuals, teammates, or supervisors when steps should be taken to augment cognitive readiness. We first designed and manufactured a forehead sensor device that includes a custom fNIRS sensor and a three-axis accelerometer designed to be mounted on the inside of a baseball cap or headband, or standard issue gear such as a helmet or surgeon’s cap. Because the conditions under which MEDIC is designed to operate are more strenuous than typical research efforts assessing cognitive workload, motion artifacts in our data were a persistent issue. Results show wavelet-based filtering improved data quality to salvage data from even the highest-motion conditions. MARA spline motion correction did not further improve data quality. Our testing shows that each of the methods is extremely effective in reducing the effects of motion transients present in the data. In combination, they are able to almost completely remove the transients in the signal while preserving cardiac and low frequency information in the signal which was previously unrecoverable. This has substantially improved the stability of the physiological measures produced by the sensors in high noise conditions

    An Unobtrusive System to Measure, Assess, and Predict Cognitive Workload in Real-World Environments

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    Across many careers, individuals face alternating periods of high and low attention and cognitive workload, which can result in impaired cognitive functioning and can be detrimental to job performance. For example, some professions (e.g., fire fighters, emergency medical personnel, doctors and nurses working in an emergency room, pilots) require long periods of low workload (boredom), followed by sudden, high-tempo operations during which they may be required to respond to an emergency and perform at peak cognitive levels. Conversely, other professions (e.g., air traffic controllers, market investors in financial industries, analysts) require long periods of high workload and multitasking during which the addition of just one more task results in cognitive overload resulting in mistakes. An unobtrusive system to measure, assess, and predict cognitive workload could warn individuals, their teammates, or their supervisors when steps should be taken to augment cognitive readiness. In this talk I will describe an approach to this problem that we have found to be successful across work domains including: (1) a suite of unobtrusive, field-ready neurophysiological, physiological, and behavioral sensors that are chosen to best suit the target environment; (2) custom algorithms and statistical techniques to process and time-align raw data originating from the sensor suite; (3) probabilistic and statistical models designed to interpret the data into the human state of interest (e.g., cognitive workload, attention, fatigue); (4) and machine-learning techniques to predict upcoming performance based on the current pattern of events, and (5) display of each piece of information depending on the needs of the target user who may or may not want to drill down into the functioning of the system to determine how conclusions about human state and performance are determined. I will then focus in on our experimental results from our custom functional near-infrared spectroscopy sensor, designed to operate in real-world environments to be worn comfortably (e.g., positioned into a baseball cap or a surgeons cap) to measure changes in brain blood oxygenation without adding burden to the individual being assessed

    Les droits disciplinaires des fonctions publiques : « unification », « harmonisation » ou « distanciation ». A propos de la loi du 26 avril 2016 relative à la déontologie et aux droits et obligations des fonctionnaires

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    The production of tt‾ , W+bb‾ and W+cc‾ is studied in the forward region of proton–proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98±0.02 fb−1 . The W bosons are reconstructed in the decays W→ℓν , where ℓ denotes muon or electron, while the b and c quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions.The production of ttt\overline{t}, W+bbW+b\overline{b} and W+ccW+c\overline{c} is studied in the forward region of proton-proton collisions collected at a centre-of-mass energy of 8 TeV by the LHCb experiment, corresponding to an integrated luminosity of 1.98 ±\pm 0.02 \mbox{fb}^{-1}. The WW bosons are reconstructed in the decays WνW\rightarrow\ell\nu, where \ell denotes muon or electron, while the bb and cc quarks are reconstructed as jets. All measured cross-sections are in agreement with next-to-leading-order Standard Model predictions

    Physics case for an LHCb Upgrade II - Opportunities in flavour physics, and beyond, in the HL-LHC era

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    The LHCb Upgrade II will fully exploit the flavour-physics opportunities of the HL-LHC, and study additional physics topics that take advantage of the forward acceptance of the LHCb spectrometer. The LHCb Upgrade I will begin operation in 2020. Consolidation will occur, and modest enhancements of the Upgrade I detector will be installed, in Long Shutdown 3 of the LHC (2025) and these are discussed here. The main Upgrade II detector will be installed in long shutdown 4 of the LHC (2030) and will build on the strengths of the current LHCb experiment and the Upgrade I. It will operate at a luminosity up to 2×1034 cm−2s−1, ten times that of the Upgrade I detector. New detector components will improve the intrinsic performance of the experiment in certain key areas. An Expression Of Interest proposing Upgrade II was submitted in February 2017. The physics case for the Upgrade II is presented here in more depth. CP-violating phases will be measured with precisions unattainable at any other envisaged facility. The experiment will probe b → sl+l−and b → dl+l− transitions in both muon and electron decays in modes not accessible at Upgrade I. Minimal flavour violation will be tested with a precision measurement of the ratio of B(B0 → μ+μ−)/B(Bs → μ+μ−). Probing charm CP violation at the 10−5 level may result in its long sought discovery. Major advances in hadron spectroscopy will be possible, which will be powerful probes of low energy QCD. Upgrade II potentially will have the highest sensitivity of all the LHC experiments on the Higgs to charm-quark couplings. Generically, the new physics mass scale probed, for fixed couplings, will almost double compared with the pre-HL-LHC era; this extended reach for flavour physics is similar to that which would be achieved by the HE-LHC proposal for the energy frontier

    LHCb upgrade software and computing : technical design report

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    This document reports the Research and Development activities that are carried out in the software and computing domains in view of the upgrade of the LHCb experiment. The implementation of a full software trigger implies major changes in the core software framework, in the event data model, and in the reconstruction algorithms. The increase of the data volumes for both real and simulated datasets requires a corresponding scaling of the distributed computing infrastructure. An implementation plan in both domains is presented, together with a risk assessment analysis

    Differential branching fraction and angular analysis of the decay B0s→ ϕμ+μ−

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    The determination of the differential branching fraction and the first angular analysis of the decay B[superscript 0][subscript 0] → ϕμ[superscript +]μ[subscript −] are presented using data, corresponding to an integrated luminosity of 1.0 fb[superscript −1], collected by the LHCb experiment at s√=7s=7 TeV. The differential branching fraction is determined in bins of q[superscript 2], the invariant dimuon mass squared. Integration over the full q[superscript 2] range yields a total branching fraction of B(B[superscript 0][subscript s]→ϕμ[superscript +]μ[subscript −])=(7.07[superscript +0.64][subscript −0.59]±0.71±0.71)) × 10[subscript −7], where the first uncertainty is statistical, the second systematic, and the third originates from the branching fraction of the normalisation channel. An angular analysis is performed to determine the angular observables F[subscript L], S[subscript 3], A[subscript 6], and A[subscript 9]. The observables are consistent with Standard Model expectations.National Science Foundation (U.S.

    Updated Determination of D⁰–D¯⁰Mixing and CP Violation Parameters with D⁰→K⁺π⁻ Decays

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    We report measurements of charm-mixing parameters based on the decay-time-dependent ratio of D⁰→K⁺π⁻ to D⁰→K⁻π⁺ rates. The analysis uses a data sample of proton-proton collisions corresponding to an integrated luminosity of 5.0  fb⁻¹ recorded by the LHCb experiment from 2011 through 2016. Assuming charge-parity (CP) symmetry, the mixing parameters are determined to be x′²=(3.9±2.7)×10⁻⁵, y′=(5.28±0.52)×10⁻³, and R[subscript D]=(3.454±0.031)×10⁻³. Without this assumption, the measurement is performed separately for D⁰ and D[over ¯]⁰ mesons, yielding a direct CP-violating asymmetry A[subscript D]=(-0.1±9.1)×10⁻³, and magnitude of the ratio of mixing parameters 1.00<|q/p|<1.35 at the 68.3% confidence level. All results include statistical and systematic uncertainties and improve significantly upon previous single-measurement determinations. No evidence for CP violation in charm mixing is observed

    Multidifferential study of identified charged hadron distributions in ZZ-tagged jets in proton-proton collisions at s=\sqrt{s}=13 TeV

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    Jet fragmentation functions are measured for the first time in proton-proton collisions for charged pions, kaons, and protons within jets recoiling against a ZZ boson. The charged-hadron distributions are studied longitudinally and transversely to the jet direction for jets with transverse momentum 20 <pT<100< p_{\textrm{T}} < 100 GeV and in the pseudorapidity range 2.5<η<42.5 < \eta < 4. The data sample was collected with the LHCb experiment at a center-of-mass energy of 13 TeV, corresponding to an integrated luminosity of 1.64 fb1^{-1}. Triple differential distributions as a function of the hadron longitudinal momentum fraction, hadron transverse momentum, and jet transverse momentum are also measured for the first time. This helps constrain transverse-momentum-dependent fragmentation functions. Differences in the shapes and magnitudes of the measured distributions for the different hadron species provide insights into the hadronization process for jets predominantly initiated by light quarks.Comment: All figures and tables, along with machine-readable versions and any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-013.html (LHCb public pages
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