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A nodeless hollow-core fiber, exposed to ambient air, enables multiline Raman generation from nitrogen, oxygen, water and carbon oxide by a 532 nm picosecond laser for the first time.
We report dispersive waves generation in an argon-filled anti-resonant nodeless fiber pumped by ultrashort pulses centered at different wavelengths. The conversion efficiency can be as high as 16% with a bandwidth below 10 nm.
Due to the new characteristics of ultra-dense networks (UDN), such as high dense deployment of wireless access points (APs), complicated handover signaling processes and irregular coverage, how to achieve mobility support and reduce user's interrupt ratio remain a difficult problem. To address these issues, based on the presented user-centric APs clustering (UCC) network architecture in UDN, a UCC...
A dense sleeve monopole antenna array is proposed for improving the noise figure (NF) and linearity of array receivers via spatial delta-sigma (Δ-Σ) noise shaping. The planar array has a spatial oversampling ratio of Ku = 4. The shared ground-shorted sleeves were optimized for low mutual coupling (less than −10 dB between adjacent monopoles). Simulated and experimental results for the proposed design...
A novel delta-sigma (Δ — Σ) modulation method is proposed for extending noise-shaping to two dimensions: space and time. The goal is to improve the noise figure (NF) and linearity of low noise amplifiers (LNAs) for use in microwave and mm-wave antenna arrays. We show that a spatially-oversampled antenna array coupled to an N-port noise-shaped LNA can diminish in-band additive noise and distortion...
In this paper, the problem of sliding mode control (SMC) for mismatched uncertain system is investigated. Some delay dependent robust asymptotical stability conditions are provided. Firstly, we give a lemma. By this lemma, a delay-dependent sufficient condition is presented by means of linear matrix inequalities (LMIs) which makes sliding mode dynamics asymptotically stable. Secondly, an adaptive...
We report a silica based nodeless hollow-core fiber guiding in the mid-infrared spectral range with low transmission loss of 50 dB/km at 2.45 μm and 130 dB/km at 3 μm, broad transmission bandwidth from 1.6 μm to 3.35 μm and single mode profile.
This paper aims to compare several location-based routing protocols in wireless sensor networks. Although location-based routing protocols have apparent limitations, it can support multi-hop data transmission. In addition, location-based routing protocols need to consume a lot of energy to transmit location information.
This paper aims to compare several hierarchical routing protocols. LEACH protocol is one of the basic and typical hierarchical routing protocols in wireless sensor networks. Some Lifetime, Density, Radius and Reliability analysis will be done for the hierarchical routing protocols. After comparisons of different hierarchical routing protocols in this paper, an approach of routing-protocol recommendation...
Wireless sensor network is one of the most important supporting technologies in the Internet of things, this paper studies the low power hierarchical routing protocol in the water environment. Energy is a vital problem in water environment. Wireless sensor network is composed of many wireless sensor nodes, which is a flexible and adaptive network. This paper studies the problem of low power consumption...
With the arrival of big data era, data mining techniques have been widely used to build models for cyber security applications such as spam filtering, malware or virus detection, and intrusion detection. This project proposes a novel approach that uses randomness to improve robustness of data mining models used in cyber security applications against attacks that try to evade detection by adapting...
The paper will develop a wireless sensor network suitable for the medical scene of smart community for the elderly in the community to provide quality health care services for the elderly. The project will improve positioning accuracy of the elderly in the smart community through the study of positioning algorithm. Meanwhile, the project will design a routing protocol most appropriate for medical...
The biological inner ear, or cochlea, is a sophisticated signal processing system that performs spectrum analysis over an ultra-broadband frequency range of ∼20 Hz to 20 kHz with exquisite sensitivity and high energy efficiency. Electronic cochlear models, which mimic the exponentially-tapered structure of the biological inner ear using transmission lines or filter cascades, have been shown to be...
A numerical study was performed to obtain insight into conduction/convection conjugate heat transfer processes during a typical experiments performed at the micro scale. The experimental work of Wang et al. [1] was used as a baseline to quantify such effects. It consisted of a 225 μm × 18.5 mm × 1.5 mm microchannel with a pillar, which had jet slits. Commercially available software package, Star CCM+,...
Sevoflurane and propofol are often used in combination to achieve a better anesthetic effect in balanced anesthesia. However, methods for on-line monitoring drug concentrations of the two anesthetics in patients are still scarce in clinic. This study proposed a non-invasive method utilizing a fast gas chromatograph (Fast GC) combined with a surface acoustic wave (SAW) sensor to simultaneously on-line...
At present study, conjugate heat transfer effects of a free-ended micropillar within a channel was investigated numerically. There is a gap between pillar tip and upper channel wall while the pillar is attached to the end wall at the other side. Two design configurations were considered based on the heater location. In one design, the bottom channel wall where the pillar is attached is the heated...
Detection of gait phase has multiple of applications such as lower limb prosthetics, drop foot stimulator, and rehabilitation assessment. Different types of wearable sensors such as force sensitive sensors (FSR), gyroscopes, and the combination of gyroscopes and accelerometers, have been used for the classification of gait phase. Among these sensors, since accelerometers are low in cost, easy to use,...
We report a high performance nodeless hollow-core anti-resonant fiber with a broadband guidance from 1050 nm to >1900 nm, a transmission attenuation of 200 dB/km, and a low bending loss of 0.25 dB/m for a 5 cm radius at wavelength of 1550 nm.
A Pressure and temperature (P&T) monitoring system based on fiber Bragg grating (FBG) and extrinsic Fabry-Perot interferometer (EFPI) for downhole application is designed and tested. The system is electronically passive, with no electronics downhole, and can monitor downhole pressure and temperature continuously without breaking in production of oil well. It is demonstrated in experimental well...
As wind power becomes a high penetration in power system, wind turbine integration performance plays a significant role in power grid operation. Wind turbine controller strategy and its coordination with pitch system, generator, convertor, etc., are key of wind turbine performance. This paper presents the work of hardware-in-the-loop (HIL) wind turbine simulative platform which is dedicated for wind...
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