16,876 research outputs found
Specific wavelength colorimeter
A self contained, specific wavelength, single beam colorimeter is described for direct spectrophotometric measurement of the concentration of a given solute in a test sample. An electrical circuit employing a photoconductive cell converts the optical output into a linear, directly readable meter output. The colorimeter is simple to operate and is adapted for use in zero gravity conditions. In a specific application, the colorimeter is designed to analyze the concentration of iodine in potable water carried aboard a space vehicle such as the 4B stage of Skylab
Customer unit substation of collective heat distribution system : Benchmark of hot water comfort test standard and methodologies
The performance assessment of dwelling heating substations in terms of level of comfort is usually studied regarding temperature overshoots, stationary temperature deviations and settling time among other parameters. In fact, several standards and test methods can be found focusing on a specific target or technology. However, these methods do not always provide clear information about hot water comfort. As a result planners, developers and customers have difficulties to compare a substation product with products using other technologies for the heating of sanitary hot water. The study investigates the compatibility of already existing methods and intends to evaluate their applicability to systems where the sanitary hot water is prepared in an instantaneous way by using a heat exchanger in a district heating substation. In order to achieve that aim, a dynamic simulation model of a test setup (using TRNSYS) has been developed. The test procedures, as well as the simulation results, are described and discussed. This analysis is expected to provide the basis for an integrated performance assessment test of this kind of devices
AoA-aware Probabilistic Indoor Location Fingerprinting using Channel State Information
With expeditious development of wireless communications, location
fingerprinting (LF) has nurtured considerable indoor location based services
(ILBSs) in the field of Internet of Things (IoT). For most pattern-matching
based LF solutions, previous works either appeal to the simple received signal
strength (RSS), which suffers from dramatic performance degradation due to
sophisticated environmental dynamics, or rely on the fine-grained physical
layer channel state information (CSI), whose intricate structure leads to an
increased computational complexity. Meanwhile, the harsh indoor environment can
also breed similar radio signatures among certain predefined reference points
(RPs), which may be randomly distributed in the area of interest, thus mightily
tampering the location mapping accuracy. To work out these dilemmas, during the
offline site survey, we first adopt autoregressive (AR) modeling entropy of CSI
amplitude as location fingerprint, which shares the structural simplicity of
RSS while reserving the most location-specific statistical channel information.
Moreover, an additional angle of arrival (AoA) fingerprint can be accurately
retrieved from CSI phase through an enhanced subspace based algorithm, which
serves to further eliminate the error-prone RP candidates. In the online phase,
by exploiting both CSI amplitude and phase information, a novel bivariate
kernel regression scheme is proposed to precisely infer the target's location.
Results from extensive indoor experiments validate the superior localization
performance of our proposed system over previous approaches
A multi-modal dance corpus for research into real-time interaction between humans in online virtual environments
We present a new, freely available, multimodal corpus for research into, amongst other areas, real-time realistic interaction between humans in online virtual environments. The specific corpus scenario focuses on an online dance class application scenario where students, with avatars driven by whatever 3D capture technology are locally available to them, can learn choerographies with teacher guidance in an online virtual ballet studio. As the data corpus is focused on this scenario, it consists of student/teacher dance choreographies concurrently captured at two different sites using a variety of media modalities, including synchronised audio rigs, multiple cameras, wearable inertial measurement devices and depth sensors. In the corpus, each of the several dancers perform a number of fixed choreographies, which are both graded according to a number of specific evaluation criteria. In addition, ground-truth dance choreography annotations are provided. Furthermore, for unsynchronised sensor modalities, the corpus also includes distinctive events for data stream synchronisation. Although the data corpus is tailored specifically for an online dance class application scenario, the data is free to download and used for any research and development purposes
The integration of on-line monitoring and reconfiguration functions using IEEE1149.4 into a safety critical automotive electronic control unit.
This paper presents an innovative application of IEEE 1149.4 and the integrated diagnostic reconfiguration (IDR) as tools for the implementation of an embedded test solution for an automotive electronic control unit, implemented as a fully integrated mixed signal system. The paper describes how the test architecture can be used for fault avoidance with results from a hardware prototype presented. The paper concludes that fault avoidance can be integrated into mixed signal electronic systems to handle key failure modes
Handbook of recommended practices for the determination of liquid monopropellant rocket engine performance
The design, installation, and operation of systems to be used for directly measuring quantities of fundamental importance to the determination of monopropellant thruster performance is described. Areas covered include: (1) force and impulse measurement; (2) propellant mass usage and flow measurement; (3) pressure measurement; (4) temperature measurement; (5) exhaust gas composition measurement; and (6) data reduction and performance determination
ATLAS Upgrade Instrumentation in the US
Planned upgrades of the LHC over the next decade should allow the machine to
operate at a center of mass energy of 14 TeV with instantaneous luminosities in
the range 5--7e34 cm^-2 s^-1. With these parameters, ATLAS could collect 3,000
fb^-1 of data in approximately 10 years. However, the conditions under which
this data would be acquired are much harsher than those currently encountered
at the LHC. For example, the number of proton-proton interactions per bunch
crossing will rise from the level of 20--30 per 50 ns crossing observed in 2012
to 140--200 every 25 ns. In order to deepen our understanding of the newly
discovered Higgs boson and to extend our searches for physics beyond that new
particle, the ATLAS detector, trigger, and readout will have to undergo
significant upgrades. In this whitepaper we describe R&D necessary for ATLAS to
continue to run effectively at the highest luminosities foreseen from the LHC.
Emphasis is placed on those R&D efforts in which US institutions are playing a
leading role.Comment: Snowmass contributed paper, 24 pages, 12 figure
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