A narrow-band transmission filter is demonstrated near normal incidence that operates through relaxation of supported-mode selection rules and is explained in the context of group theory. We calculated the transverse ...
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A narrow-band transmission filter is demonstrated near normal incidence that operates through relaxation of supported-mode selection rules and is explained in the context of group theory. We calculated the transverse magnetic and transverse electric dispersion relations of a dielectric grating in the subwavelength and near-wavelength region using finite element modal analysis and determine the modes' corresponding irreducible representations. Coupling to select transverse magnetic modes at normal incidence is optimized to yield broadband high reflectance that acts as the background for the transmission filter. While some modes couple at normal incidence, others are shown to remain inaccessible due to symmetry mismatch. Away from normal incidence, the reduced symmetry relaxes the selection rules, enabling weak coupling between the incident field and these symmetry-protected modes. This weak coupling produces narrow transmission bands within the opaque background. Furthermore, by choosing the plane of incidence to include or exclude the grating periodicity, we show that orthogonal mode sets can independently be selected to couple to the incident light, yielding separate transmission bands. This spectral filtering is experimentally demonstrated with a suspended silicon grating in the infrared spectrum (7–14μm), which agrees well with simulated transmittance spectra and modal analysis.
The advances of electronics provide options for improved monitoring of patients in clinical environment. Medical applications like blood pressure monitoring require precise and wireless altitude measurement in indoor ...
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The advances of electronics provide options for improved monitoring of patients in clinical environment. Medical applications like blood pressure monitoring require precise and wireless altitude measurement in indoor environment. An error of more than a few centimeters bears a risk of mistreatment of patients. Furthermore, user requirements like small form factor, usability and robust operation are important in the medical field. Existing evaluations of indoor positioning systems focus on accuracy analysis of x- and y-coordinates, not on the z-coordinate (altitude). In this paper, we define evaluation criteria for altitude estimation in medical applications. We compare an Ultra-Wide-Band indoor positioning system, an optical Microsoft Kinect camera system and our own development of a wireless barometric sensor against these criteria. We present a comparative measurement setup, results and a final evaluation of the three systems in an indoor environment.
Background: Surveillance of health care-associated infections is an essential component of infection prevention programs, but conventional systems are labor intensive and performance dependent. Objective: To develop a...
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Continuum methods offer a high-fidelity means of simulating plasma kinetics. While computationally intensive, these methods are advantageous because they can be cast in conservation-law form, are not susceptible to no...
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Continuum methods offer a high-fidelity means of simulating plasma kinetics. While computationally intensive, these methods are advantageous because they can be cast in conservation-law form, are not susceptible to noise, and can be implemented using high-order numerical methods. Advances in continuum method capabilities for modeling kinetic phenomena in plasmas require the development of validation tools in higher dimensional phase space and an ability to handle non-cartesian geometries. To that end, a new benchmark for validating Vlasov-Poisson simulations in 3D (x, vx, vy) is presented [1]. The benchmark is based on the Dory-Guest-Harris instability and is successfully used to validate a continuum finite volume algorithm. To address challenges associated with non-cartesian geometries, unique features of cylindrical phase space coordinates are described. Preliminary results of continuum kinetic simulations in 4D (r,z,vr,vz) phase space are presented. [ABSTRACT FROM AUTHOR]
The great diversity in the architecture of biomedical devices, coupled with their different communication protocols, has hindered the implementation of systems that need access to these devices. Given these difference...
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The great diversity in the architecture of biomedical devices, coupled with their different communication protocols, has hindered the implementation of systems that need access to these devices. Given these differences, arises the need to provide access to such devices in a transparent way. In this sense, this paper proposes an service-oriented architecture to access biomedical devices as a way to abstract the mechanism for writing and reading data on these devices, thus contributing to the increase in quality and productivity of biomedical systems in order to enable that the focus of the development team of biomedical software is almost exclusively intended for its functional requirements, i.e. business rules relevant to the problem domain. For the development of this work, technologies such as the XML language and the Java programming language were used and concepts of Software engineering as Design Patterns. After the proposition of the architecture, tests in order to validate the proposed architecture were performed.
A search for heavy pseudoscalar (A) and scalar (H) Higgs bosons decaying into a top quark pair (tt¯) has been performed with 20.3 fb−1 of proton-proton collision data collected by the ATLAS experiment at the Lar...
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A search for heavy pseudoscalar (A) and scalar (H) Higgs bosons decaying into a top quark pair (tt¯) has been performed with 20.3 fb−1 of proton-proton collision data collected by the ATLAS experiment at the Large Hadron Collider at a center-of-mass energy s=8 TeV. Interference effects between the signal process and standard model tt¯ production, which are expected to distort the signal shape from a single peak to a peak-dip structure, are taken into account. No significant deviation from the standard model prediction is observed in the tt¯ invariant mass spectrum in final states with an electron or muon, large missing transverse momentum, and at least four jets. The results are interpreted within the context of a type-II two-Higgs-doublet model. Exclusion limits on the signal strength are derived as a function of the mass mA/H and the ratio of the vacuum expectation values of the two Higgs fields, tanβ, for mA/H>500 GeV.
Several extensions of the standard model predict associated production of dark-matter particles with a Higgs boson. Such processes are searched for in final states with missing transverse momentum and a Higgs boson de...
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Several extensions of the standard model predict associated production of dark-matter particles with a Higgs boson. Such processes are searched for in final states with missing transverse momentum and a Higgs boson decaying to a bb¯ pair with the ATLAS detector using 36.1 fb−1 of pp collisions at a center-of-mass energy of 13 TeV at the LHC. The observed data are in agreement with the standard model predictions and limits are placed on the associated production of dark-matter particles and a Higgs boson.
A search for the dimuon decay of the Higgs boson was performed using data corresponding to an integrated luminosity of 36.1 fb−1 collected with the ATLAS detector in pp collisions at s=13 TeV at the Large Hadron Col...
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A search for the dimuon decay of the Higgs boson was performed using data corresponding to an integrated luminosity of 36.1 fb−1 collected with the ATLAS detector in pp collisions at s=13 TeV at the Large Hadron Collider. No significant excess is observed above the expected background. The observed (expected) upper limit on the cross section times branching ratio is 3.0 (3.1) times the Standard Model prediction at the 95% confidence level for a Higgs boson mass of 125 GeV. When combined with the pp collision data at s=7 TeV and s=8 TeV, the observed (expected) upper limit is 2.8 (2.9) times the Standard Model prediction.
Vehicular networks will play an important role in future smart cities. Connected vehicles will be able to provide entertainment content to their users in order to make traffic situations more enjoyable. However, the a...
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Vehicular networks will play an important role in future smart cities. Connected vehicles will be able to provide entertainment content to their users in order to make traffic situations more enjoyable. However, the amount of bandwidth available to the vehicles may not be enough to satisfy all of them. In this case, we can say that a conflict of interest occurred and then must the solved as fair as possible. In this work, we propose a solution to solve this kind of collective conflict. Our solution balances users' satisfaction with resources consumption as it is capable of choosing the most adequate resolution algorithm based on the current application's situation. The results showed that with our solution it was possible to achieve adequate satisfaction levels, with low response time and controlled network usage.
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