gebhart/patrepeval huggingface dataset:
Sparse channel estimation in millimeter wave communications: Exploiting joint AoD-AoA angular spread (2017)

In this paper, channel estimation in millimeter wave (mmWave) communication systems is considered. In contrast to prevailing mmWave channel estimation methods exploiting the sparsity nature of the channel, we move one step further by exploiting the joint AoD-AoA angular spread. By formulating the channel estimation as a block-sparse signal recovery with an underlying two-dimensional cluster feature, we propose a two-dimensional sparse Bayesian learning method without a priori knowledge of two-dimensional angular spread patterns. It essentially couples the channel path power at one angular direction with its two-dimensional AoD-AoA neighboring directions. Compared with existing sparse mmWave channel estimation methods, the proposed method is numerically verified to reduce the training overhead and channel estimation error.
Scanning Near‐Field Ultrasound Holography (2010)

Abstract Nondestructive metrology of nanoscale structures, embedded defects, and buried patterns in microelectronic devices is a daunting challenge. Similarly, noninvasive nanoscale imaging of subcellular components, spatiotemporal transfection of pathogens, and environmental pollutants in a biological cell is an equally formidable problem. Various traditional imaging methods using optics, acoustics, electron beams, X‐rays and the like are either invasive or are incapable of achieving nanoscale lateral resolution. We have developed an innovative scanning near‐field ultrasound holography (SNFUH) approach as a promising solution to this challenge. SNFUH exploits viscoelastic contrast between subsurface structures and matrix for imaging the “ phase ” component of ultrasound scattering. The experimental setup is a modified scanning probe microscopy (SPM) platform, wherein ultrasonic waves are excited at the probe tip and in the sample bulk, using transducers. Ultrasonic plane waves launched from the bottom of the specimen experience perturbations due to changes in viscoelastic properties and/or geometry of the embedded structures. These perturbations are detected and imaged via SNFUH's optoelectronic feedback system. The SNFUH system has already been used to image nanoscale structures in microelectronic and biological specimens, and further development and understanding will considerably aid in the development of nanoscale noninvasive metrology fields.
An evaluation of 3D modality independent elastography robustness to boundary condition noise (2007)

This work explores an inverse problem technique of extracting soft tissue elasticity information via nonrigid model-based image registration. The algorithm uses the elastic properties of the tissue in a biomechanical model to achieve maximal similarity between image data acquired under different states of loading. A framework capable of handling fully three-dimensional models and image data has been recently developed utilizing parallel computing and iterative sparse matrix solvers. For this preliminary investigation, a series of simulation experiments with clinical image data of human breast are used to test the robustness of the algorithm to expected mis-estimation of displacement boundary conditions encountered in real-world situations. Three methods of automated point correspondence are also examined as means of generating boundary conditions for the algorithm.
Validation of Global Performance Numerical Design Tools Used for Design of Floating Offshore Wind Turbines (2015)

In an effort to harness the abundant offshore wind resource over deepwater, the development of numerical design tools for floating offshore wind turbines (FOWTs) has progressed steadily in recent years. However, at present, a validated model capable of completely coupling the full elastodynamic response between the mooring system, floating support structure, turbine tower and the wind turbine is not commercially available. The University of Maine has developed a new FOWT design, VolturnUS, which utilizes a concrete semi-submersible hull. For the VolturnUS design effort a number of numerical models were developed to analyze the system’s global performance. This paper presents the results of a validation study conducted to quantify the accuracy and suitability of a subset of these models for use in the design of the VolturnUS FOWT. Validation was conducted via comparisons of numerical model results to test data obtained from a 1:50 scale model testing campaign conducted by the University of Maine at the Maritime Research Institute, Netherlands offshore basin. The validation study evaluated the performance and capabilities of the numerical models over a range of design conditions. Emphasis was placed on design load cases (DLCs), which were found to govern the design of the FOWT. The DLCs follow the American Bureau of Shipping’s (ABS) Guide for Building and Classing Floating Offshore Wind Turbines. Through this method of model validation this work sought to quantify the numerical models’ accuracy, highlight their limitations, justify design assumptions, and identify areas requiring further development in the field of FOWT numerical modeling.
Worldwide Occurrence of Feline Hemoplasma Infections in Wild Felid Species (2007)

While hemoplasma infections in domestic cats are well studied, almost no information is available on their occurrence in wild felids. The aims of the present study were to investigate wild felid species as possible reservoirs of feline hemoplasmas and the molecular characterization of the hemoplasma isolates. Blood samples from the following 257 wild felids were analyzed: 35 Iberian lynxes from Spain, 36 Eurasian lynxes from Switzerland, 31 European wildcats from France, 45 lions from Tanzania, and 110 Brazilian wild felids, including 12 wild felid species kept in zoos and one free-ranging ocelot. Using real-time PCR, feline hemoplasmas were detected in samples of the following species: Iberian lynx, Eurasian lynx, European wildcat, lion, puma, oncilla, Geoffroy's cat, margay, and ocelot. "Candidatus Mycoplasma haemominutum" was the most common feline hemoplasma in Iberian lynxes, Eurasian lynxes, Serengeti lions, and Brazilian wild felids, whereas "Candidatus Mycoplasma turicensis" was the most prevalent in European wildcats; hemoplasma coinfections were frequently observed. Hemoplasma infection was associated with species and free-ranging status of the felids in all animals and with feline leukemia virus provirus-positive status in European wildcats. Phylogenetic analyses of the 16S rRNA and the partial RNase P gene revealed that most hemoplasma isolates exhibit high sequence identities to domestic cat-derived isolates, although some isolates form different subclusters within the phylogenetic tree. In conclusion, 9 out of 15 wild felid species from three different continents were found to be infected with feline hemoplasmas. The effect of feline hemoplasma infections on wild felid populations needs to be further investigated.
Multi-View Video Coding using View Interpolation and Reference Picture Selection (2006)

We propose a new multi-view video coding method using adaptive selection of motion/disparity compensation based on H.264/AVC. One of the key points of the proposed method is the use of view interpolation as a tool for disparity compensation by assigning reference picture indices to interpolated images. Experimental results show that significant gains can be obtained compared to the conventional approach that was often used
Magneto-optical media suitable for short wavelength reading (1993)

A complex magnetic multilayer, in which a layer with a high Kerr rotation angle was sandwiched by layers with a large coercivity, is described. This multilayer is thin enough ( approximately 200 AA) to realize the reflective type structure to enhance the Kerr rotation angle and to obtain a high C/N in a wavelength of 532 nm. It is found that it has a reasonable reliability under a severe condition. This magnetic multilayer demonstrates higher recording sensitivity compared with a conventional magnetic single layer.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
Selected Applications of Ultra-high Q Whispering Gallery Mode Resonators (2015)

Advances in physics and applications of whispering gallery mode (WGM) resonators have provided a unique opportunity for the development of devices and subsystems for a myriad of applications. In this tutorial selected applications that utilize linear and nonlinear properties of WGM resonators will be presented.
Development of an Adaptive Passive Vibro-Acoustic Device for Payload Fairings (2003)

Launch acoustic loads have the potential to damage sensitive payloads within a payload fairing. A typical payload fairing will exhibit cavity resonance modes related to its dimensions. These modes are excited both by the vibrations transmitted through the structure during launch, and by acoustic ground reflections coupled into the system during the initial launch phase. At low frequencies, cavity resonance modes are often responsible for peaks, or local maximums, in acoustic transmission. Conventional acoustic blankets mitigate the acoustic environment within a payload fairing, but are generally only effective above 250 Hz. In order to address this deficiency, the Air Force Research Laboratory Space Vehicles Directorate developed the Passive Vibro-Acoustic Device (PVAD), which employs a passive attenuator and a tuned-mass damper to mitigate a low-frequency acoustic cavity mode and an acoustically-coupled structural mode simultaneously. Each device must be tuned to a specific mode, however, and the cavity mode frequencies are sensitive to winter/summer temperature variations and varying payload volumes. Hence the performance of a purely passive device may vary significantly from launch to launch. In this work we present an Adaptive VibroAcoustic Device (AVAD), which overcomes sensitivity to temperature and other factors by adjusting the passive attenuator to a mode of the current acoustic environment during an autonomous training period shortly before launch. The device also has the added bonus of being able to add damping to several modes. 44th AIAA/ASME/ASCE/AHS Structures, Structural Dynamics, and Materials Confere 7-10 April 2003, Norfolk, Virginia AIAA 2003-1814
Unstable resonator with canceling edge waves (1982)

Diffractive feedback from the edge of the output mirror of an unstable resonator can cause intensity spikes and make the resonator sensitive to tilts. A design for a stepped feedback mirror is proposed that substantially reduces the effect of edge diffraction on the resonator modes. The predicted results are a more uniform intensity profile and greatly reduced tilt sensitivity.
Coal flow meter development Phase III, evaluation model (1983)

Work conducted under Phase III has demonstrated the feasibility of using ESR and NMR techniques for on-stream coal flowmetering and analysis and has resulted in the development of an Evaluation Model which incorporates both ESR and NMR detectors to sense pneumatically transported coal flowing through a 3/8-inch pipe. Sensory data required to satisfy equations for flowmetering and analysis have been made available in the instrument. A computer program to perform the data processing and to compute the relevant coal parameters from the sensed ESR and NMR data has been developed and used in the integral microcomputer of the instrument. Laboratory data has verified the operation of the instrument and the computer program has provided readouts of selected properties of three types of coal on the digital panel meter.
Fabrication of multilayer ferroelectric films (1999)

Abstract Multilayers of strontium bismuth tantalate (Sr0.9Bi2.2Ta2O9, SBT) with bismuth titanate (Bi4Ti3O12, BT), and SBT and strontium bismuth niobate (Sr0.9Bi2.2Nb2O9, SBN) with BT were prepared by chemical solution deposition (CSD). The CSD solutions were a mixture of strontium, tantalum, niobium and titanium butoxyethoxides and bismuth ethylhexanoate dissolved in butoxyethanol. SBT films were fabricated and annealed at 800°C for 60 min. Generally, all capacitors of the SBT films tested had low resistance with as-deposited Pt top electrodes and no ferroelectricity could be measured. After a post electrode anneal at 800°C for 30 min, a percentage of capacitors could be tested for ferroelectricity, and a 2Pr of 15 μC/cm2at 3V was typically measured. Multilayer SBT, and SBT and SBN with BT were rapidly thermally annealed for a total (including post electrode anneal) of 20–40 min at 750°C. The multilayer SBT and SBN with BT, and SBT with BT films exhibited a wide range of 2Pr values ranging from 2–14 μC/cm2at 3V but had a larger percentage of measurable capacitors after post electrode anneal than the SBT only films. In addition, no fatigue was observed after 1011cycles in a SBT with BT multilayer structure.
Development and characterisation of laser power converters for optical power transfer applications (2014)

Interest in single‐junction photovoltaic devices has been renewed in recent years due to their potential to produce very high optical to electrical conversion efficiencies under monochromatic illumination. A single‐junction photovoltaic converter was developed for monochromatic radiation (a laser power converter (LPC)) to specifically convert monochromatic light at a wavelength of 1.55 µm (which is eye and skin safe up to a power density of 1 kW/m 2 ) into electrical energy. Such devices find use in space‐based laser power transfer, as well as fibre optic power delivery and the remote powering of subcutaneous equipment and other electrical devices. The LPC design is based on lattice‐matched InGaAsP/InP, which includes elements for photon recycling and efficient carrier extraction. Here, the design process is reported based on computer simulated characteristics, and compare them to experimental data from both laboratory and field tests. The LPC demonstrates a conversion efficiency of 45% ± 1% under illumination at 1.55 µm and 1 kW/m 2 , and a conversion efficiency of 13.3% under AM1.5 solar illumination for potential dual‐use applications. With further design optimisation, it has been predicted that the conversion efficiency will exceed 50% at 1.55 µm and 1 kW/m 2 .
Molecular Biology of Mu Opioid Receptors (2010)

The cloning of the Mu opioid receptor has led to the identification of a large series of splice variants. The gene is complex, with two independent promoters responsible for two distinct sets of splice variants. The primary promoter, associated with exon 1, encodes the majority of the variants, while a second promoter upstream of the first is associated with exon 11 (E11). The majority of the variants generated by the exon 1 promoter involve splicing at the C-terminus of the receptor, without any changes in the transmembrane domains or binding pocket. Most of the variants produced by the E11 promoter have unusual structures with six transmembrane domains. However, both sets of variants are functionally important, as shown by the actions of opioids in their respective knockout mice, providing a new perspective on understanding complex Mu opioid actions in animals and humans.
Cutoff Rate Optimal Binary Inputs with (2006)

We use the cutoff rate to study the optimal binary input distributions for the Rayleigh flat-fading channel with imperfect receiver channel state information (CSI). First, we evaluate the cutoff rate and analyze the optimal binary input as a function of the CSI quality and receiver SNR. Next, we study the limiting distributions - BPSK and On-Off Keying (OOK) - and derive an analytic design rule that allows adaptive switching between these two as the receiver CSI changes. We establish the virtues of a modulation scheme that employs only these limiting distributions, rather than the full spectrum of binary inputs. Finally, we use our results to design an adaptive modulation scheme for Pilot Symbol Assisted Modulation systems. We show that switching between just BPSK and equiprobable-OOK is nearly optimal for moderate to large SNR, and that switching between BPSK and generalized-OOK is nearly optimal for all SNR.
Solution Properties of a Novel Polysaccharide Derivative (2004)

Abstract A novel self-assembly polysaccharide derivative; hydrophobically (stearyl alkyl group) and hydrophilically (sulfonic acid salt group) modified hydroxyethylcellulose (HHM-HEC), has the unique rheological properties in aqueous solutions.
On-cuip temperature gradient liquid chromatography (2005)

We report here the first MEMS temperature-programmable high pressure parylene column with integrated thermal isolation and electrochemical sensor for on-chip temperature gradient liquid chromatography. Two sets of devices for different high performance liquid chromatography (HPLC) criteria were fabricated. The separation and detection of derivatized amino acids sample was successfully demonstrated. Compared with other temperature gradient HPLC systems which use "macro oven" to generate temporal temperature gradient in the column, our device's thermal performance is greatly improved by orders of magnitude without the sacrifice of chromatography quality.
Low-Friction, Low-Profile, High-Moment Two-Axis Joint (2010)

The two-axis joint is a mechanical device that provides two-degrees-of-freedom motion between connected components. A compact, moment-resistant, two-axis joint is used to connect an electromechanical actuator to its driven structural members. Due to the requirements of the overall mechanism, the joint has a low profile to fit within the allowable space, low friction, and high moment-reacting capability. The mechanical arrangement of this joint can withstand high moments when loads are applied. These features allow the joint to be used in tight spaces where a high load capability is required, as well as in applications where penetrating the mounting surface is not an option or where surface mounting is required. The joint consists of one base, one clevis, one cap, two needle bearings, and a circular shim. The base of the joint is the housing (the base and the cap together), and is connected to the grounding structure via fasteners and a bolt pattern. Captive within the housing, between the base and the cap, are the rotating clevis and the needle bearings. The clevis is attached to the mechanical system (linear actuator) via a pin. This pin, and the rotational movement of the clevis with respect to the housing, provides two rotational degrees of freedom. The larger diameter flange of the clevis is sandwiched between a pair of needle bearings, one on each side of the flange. During the assembly of the two-axis joint, the circular shims are used to adjust the amount of preload that is applied to the needle bearings. The above arrangement enables the joint to handle high moments with minimal friction. To achieve the high-moment capability within a low-profile joint, the use of depth of engagement (like that of a conventional rotating shaft) to react moment is replaced with planar engagement parallel to the mounting surface. The needle bearings with the clevis flange provide the surface area to react the clevis loads/moments into the joint housing while providing minimal friction during rotation. The diameter of the flange and the bearings can be increased to react higher loads and still maintain a compact surface mounting capability. This type of joint can be used in a wide variety of mechanisms and mechanical systems. It is especially effective where precise, smooth, continuous motion is required. For example, the joint can be used at the end of a linear actuator that is required to extend and rotate simultaneously. The current design application is for use in a spacecraft docking-system capture mechanism. Other applications might include industrial robotic or assembly line apparatuses, positioning systems, or in the motion-based simulator industry that employs complex, multi-axis manipulators for various types of motions.
SERS Biosensor for Label Free Monitoring of Environmental Stress (2013)

The increasing threat of environmental contamination with toxins has led to substantial advances in biosensor techniques. So far, there is no label free portable dynamic sensor, which can replace standard ELISA to monitor the levels of toxins intracellular in living cells or organisms. Our group has developed a silver nanoparticle (AgNPs) based Surface Enhanced Raman Spectroscopy (SERS) sensor to detect levels of stress protein (RAD54) expressed by a human surrogate (yeast) in response to environmental toxins (H <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> and U.V.). The fabricated SERS sensor allowed label-free and rapid detection over the ELISA and showed good correlation in extracellular detection of RAD54. In our progress towards intracellular detection, we tested three possible techniques (active, passive and peptide facilitated) for efficient delivery of AgNPs. TAT-HA2 facilitated delivery resulted in increased and rapid uptake of AgNPs as compared to passive diffusion. Dynamic monitoring of RAD54 marker expressed by living cells in response to environmental stress using multiplex SERS sensor with targeting and delivery moieties is in progress.
Discovery of <i>S</i>-Nitrosoglutathione Reductase Inhibitors: Potential Agents for the Treatment of Asthma and Other Inflammatory Diseases (2011)

S-Nitrosoglutathione reductase (GSNOR) regulates S-nitrosothiols (SNOs) and nitric oxide (NO) in vivo through catabolism of S-nitrosoglutathione (GSNO). GSNOR and the anti-inflammatory and smooth muscle relaxant activities of SNOs, GSNO, and NO play significant roles in pulmonary, cardiovascular, and gastrointestinal function. In GSNOR knockout mice, basal airway tone is reduced and the response to challenge with bronchoconstrictors or airway allergens is attenuated. Consequently, GSNOR has emerged as an attractive therapeutic target for several clinically important human diseases. As such, small molecule inhibitors of GSNOR were developed. These GSNOR inhibitors were potent, selective, and efficacious in animal models of inflammatory disease characterized by reduced levels of GSNO and bioavailable NO. N6022, a potent and reversible GSNOR inhibitor, reduced bronchoconstriction and pulmonary inflammation in a mouse model of asthma and demonstrated an acceptable safety profile. N6022 is currently in clinical development as a potential agent for the treatment of acute asthma.