323 research outputs found
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SkinnySensor: Enabling Battery-Less Wearable Sensors Via Intrabody Power Transfer
Tremendousadvancement inultra-low powerelectronics and radiocommunica tionshas significantly contributed towards the fabrication of miniaturized biomedical sensors capable of capturing physiological data and transmitting them wirelessly. However, most of the wearable sensors require a battery for their operation. The battery serves as one of the critical bottlenecks to the development of novel wearable applications, as the limitations offered by batteries are affecting the development of new form-factors and longevity of wearable devices. In this work, we introduce a novel concept, namely Intra-Body Power Transfer (IBPT), to alleviate the limitations and problems associated with batteries, and enable wireless, batteryless wearable devices. The innovation of IBPT is to utilize the human body as the medium to transfer power to passive wearable devices, as opposed to employingon-boardbatteries for each individual device. The proposed platform eliminates the on-board rigid battery for ultra-low power and ultra-miniaturized sensors such that their form-factor can be flexible, ergonomically designed to be placed on small body parts. The platform also eliminates the need for battery maintenance (e.g., recharging or replacement) for multiple wearable devices other than the central power source. The performance of the developed system is tested and evaluated in comparison to traditional Radio Frequency based solutions that can be harmful to human interaction. The system developed is capable of harvesting on average 217µW at 0.43V and provides an average sleep/high impedance mode voltage of 4.5V
Inferring the gravitational wave memory for binary coalescence events
Full, non-linear general relativity predicts a memory effect for
gravitational waves. For compact binary coalescence, the total gravitational
memory serves as an inferred observable, conceptually on the same footing as
the mass and the spin of the final black hole. Given candidate waveforms for
any LIGO event, then, one can calculate the posterior probability distribution
functions for the total gravitational memory, and use them to compare and
contrast the waveforms. In this paper we present these posterior distributions
for the binary black hole merger events reported in the first Gravitational
Wave Transient Catalog (GWTC-1), using the Phenomenological and
Effective-One-Body waveforms. On the whole, the two sets of posterior
distributions agree with each other quite well though we find larger
discrepancies for the mode of the memory. This signals a possible
source of systematic errors that was not captured by the posterior
distributions of other inferred observables. Thus, the posterior distributions
of various angular modes of total memory can serve as diagnostic tools to
further improve the waveforms. Analyses such as this would be valuable
especially for future events as the sensitivity of ground based detectors
improves, and for LISA which could measure the total gravitational memory
directly.Comment: 15 pages, 6 figure
New insights on structure and stratigraphic interpretation for assessing the hydrocarbon potentiality of the offshore Nile Delta basin, Egypt
The study area lies around the petroleum provinces of the Egyptian Offshore Nile Delta basin. The existing exploration data are sparse, and any effort made on the strati-structural interpretation is challenging for exploratory drilling campaigns, even with meager well control. Keeping in view the issues and major challenges, the authors propose new methodologies, tools and new insights into the interpretation of the existing data and information, to make the study area more attractive for investors and detailed exploration studies. The published geological work existing within the vicinity of the study area is an added value to the new insights of current interpretation and knowledge acquisition. Pliocene–Pleistocene section is the main target in the study area, since it has quality reservoirs, holding commercial hydrocarbons. Pre-salt source rocks may have charged the reservoirs in the study area. Structural complexities and heterogeneities at target levels are likely to impact the seismic wavelet property intricacies and thus the data processing qualities. Post- and pre-salt tectonics in the northern part of Sinai, the Nile Cone, and how they affect the structural framework and the seismic interpretation work in the study area are described. For the purpose of understanding the combinational trapping mechanism, stratigraphic features and the structural geology are integrated using new tools and technologies. Several strati-structural plays are interpreted in the study area that support the detailed exploration campaigns, and the existing major hydrocarbon plays associated within shelf, slope and deep-marine geological events in nearby offshore regions. Diapir salt, rotated fault blocks and growth faults within syn-sediment systems are other plays to be investigated. The study is an effort of compiled work from many published sources, putting all ideas into a positive perspective and has better understanding of new opportunities, leads and prospects for investment purposes in the Nile Delta offshore basin
Assisted hatching in mouse embryos using a noncontact Ho:YSGG laser system
PurposeA noncontact holmium:yttrium scandium gallium garnet (Ho:YSGG) laser system has been designed and tested for the micromanipulation of mammalian embryos. The purpose of this preliminary investigation was to determine the effectiveness of this laser for assisted hatching and evaluate its impact on embryo viability. The Ho:YSGG system, utilizing 250-microsecond pulses at a wavelength of 2.1 microns and 4 Hz, was used to remove a portion of the zona pellucida (ZP) of two- to four-cell FVB mouse embryos.ResultsIn the first experiment there was no difference in blastocyst production or hatching rates following laser or conventional assisted hatching (LAH or AH, respectively) in contrast to control embryos cultured in a 5% CO2 humidified air incubator at 37 degrees C. In the second experiment a blastocyst antihatching culture model was employed and LAH-treated embryos were cultured in a serum-free HTF medium (HTF-o). Blastocyst formation was not influenced by LAH treatment and hatching was increased (P < 0.01) from 4 to 60% compared to HTF-o control group.ConclusionsThese preliminary data demonstrate the utility and nontoxic properties of the Ho:YSGG laser system for quick and precise ZP drilling
Vegetation history and climatic fluctuations on a transect along the Dead Sea west shore and impact on past societies over the last 3500 years.
This study represents the vegetation history of the last 3500 years and conducts an analysis of the climatic fluctuations on a 75 km long transect on the western Dead Sea shore. Palynological and sedimentological data are available from six cores near Mount Sedom, Ein Boqueq, and Ein Gedi and from outcrops near Ze'elim and Ein Feshkha. The comparison of the pollen data with the lake levels shows synchronous trends. During the Middle Bronze Age, Iron Age and Hellenistic to Byzantine Period the high lake level of the Dead Sea signals an increase in precipitation. Contemporaneously, values of cultivated plants indicate an increase in agriculture. Lake level is low during the Late Bronze Age, within the Iron Age and at the end of the Byzantine period, indicating dry periods when all pds show a decrease of cultivated plants. Forest regeneration led by drought-resistant pines is observed in all pollen diagrams (pds) following the agricultural decline in the Byzantine period and, in the pds near Ein Boqeq, Ze'elim and Ein Feshkha, during the late Iron Age. The modern vegetation gradient is reflected in the palaeo-records: a stronger expansion of Mediterranean vegetation and cultivated plants in the northern sites is recognisable
FTC Titans #17576 ENGINEERING PORTFOLIO
IMSA\u27s FTC Robotics Team, the FTC TITANS, was recently recognized at an educational STEM conference presenting to the student body of Orrington Elementary and invited to present at professional meetings for Molex and Caterpillar/Trimble Connectivity to spread robotics to almost 100 engineers and STEM professionals, both at the student and professional levels.
We have used STEM education and robotics to inspire over 6300 people across the globe. The team was recently awarded the 1st Place Connect Award for professional outreach and 2nd Place Inspire (Championship) Award and is excited to be competing at the State Competition.https://digitalcommons.imsa.edu/cii_dsw/1004/thumbnail.jp
Deep Radial-Basis Value Functions for Continuous Control
A core operation in reinforcement learning (RL) is finding an action that is
optimal with respect to a learned value function. This operation is often
challenging when the learned value function takes continuous actions as input.
We introduce deep radial-basis value functions (RBVFs): value functions learned
using a deep network with a radial-basis function (RBF) output layer. We show
that the maximum action-value with respect to a deep RBVF can be approximated
easily and accurately. Moreover, deep RBVFs can represent any true value
function owing to their support for universal function approximation. We extend
the standard DQN algorithm to continuous control by endowing the agent with a
deep RBVF. We show that the resultant agent, called RBF-DQN, significantly
outperforms value-function-only baselines, and is competitive with
state-of-the-art actor-critic algorithms.Comment: In Proceedings of the 35th AAAI Conference on Artificial Intelligence
(AAAI
Comparing Remnant Properties from Horizon Data and Asymptotic Data in Numerical Relativity
We present a new study of remnant black hole properties from 13 binary black
hole systems, numerically evolved using the Spectral Einstein Code. The mass,
spin, and recoil velocity of each remnant were determined quasi-locally from
apparent horizon data and asymptotically from Bondi data computed at future null infinity using SpECTRE's Cauchy
characteristic evolution. We compare these independent measurements of the
remnant properties in the bulk and on the boundary of the spacetime, giving
insight into how well asymptotic data are able to reproduce local properties of
the remnant black hole in numerical relativity. We also discuss the theoretical
framework for connecting horizon quantities to asymptotic quantities and how it
relates to our results. This study recommends a simple improvement to the
recoil velocities reported in the Simulating eXtreme Spacetimes waveform
catalog, provides an improvement to future surrogate remnant models, and offers
new analysis techniques for evaluating the physical accuracy of numerical
simulations.Comment: 14 pages, 4 figures, 1 table; published Physical Review
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