gebhart/patrepeval huggingface dataset:
Experimental demonstration of complete photonic band gap in two-dimensional photonic crystal slabs (2005)

The realization of a photonic band gap (PBG)—not only for transverse electric (TE), but also transverse magnetic (TM)-like polarization modes in two-dimensional photonic crystal slab—is of interest for various applications. Such a complete PBG has been investigated theoretically in two-dimensional structures of which thickness is infinity. However, a complete PBG has not been demonstrated in feasible two-dimensional slab structure. In this letter, we propose two-dimensional photonic crystal slabs consisting of a triangular lattice of triangular air holes to achieve a complete PBG, and report the transmission spectra of fabricated samples. The results indicate that the degeneracy between the first and second band at the J point for TM-like polarization mode is solved, and PBG for TM-like polarization mode is obtained. Finally, we confirm the overlap of PBG between TE- and TM-like polarization modes.
Fourier imaging using rf phase encoding (1986)

Fourier imaging methods encode information in the amplitudes and phases of a NMR signal over multiple acquisitions. Several of the techniques that can be used for encoding this information are reviewed and a general theory of phase encoding presented. The discussion is then extended to include encoding as part of the rf excitation sequence. Radiofrequency phase encoding can be obtained using tailored excitation techniques or special-purpose rf field gradient coils, and may be applied prior to excitation or incorporated within the excitation or refocusing pulses. This phase-encoding method may be used for spatial and spectral discrimination, as well as being combined with other methods of image formation. An example of the proposed imaging method is described which enables Fourier imaging of short T2 signals.
A 60 GHz code-modulated interferometric imaging system using a phased array (2020)

This paper presents a millimeter-wave code-modulated interferometric imaging system, which is a lens-less approach to realizing imagers using repurposed phased arrays. To use a phased array as an interferometer, incoming signals are code modulated using phase shifters, multiplexed using a power combiner, and processed through a shared receiver chain. An interference pattern is then obtained by a squaring operation, from which complex visibilities can be demodulated. Here, a four-element 60-GHz phased array chip is packaged with slot antennas, and a single 60-GHz output is measured using a power detector. This scalar measurement is then demodulated to obtain the interferometric visibilities. The four-element phased array is thinned to obtain a 13-pixel image and the system is demonstrated through a point-source detected at different locations.
Encasing Undisturbed Soil Cores in Plastic (1973)

Abstract A technique was developed using a 10.2‐cm‐diameter soil sampler to obtain undisturbed soil cores encased in heat‐shrinkable tubes. Six cores were taken in feedlots, five from sandy loam, and one from a silty clay loam. The undisturbed soil core is placed inside the plastic tube during the sampling operation, thereby minimizing core handling and possible fracture.
An improved linear ion trap physics package (1993)

This article describes an improvement in the architecture of the physics package used in the Linear Ion Trap (LIT)-based frequency standard recently developed at JPL. This new design is based on the observation that ions can be moved along the axis of an LIT by applied dc voltages. The state selection and interrogation region can be separated from the more critical microwave resonance region where the multiplied local oscillator signal is compared with the stable atomic transition. This separation relaxes many of the design constraints of the present units. Improvements include increased frequency stability and a substantial reduction in size, mass, and cost of the final frequency standard.
Human papillomavirus (HPV) type 50, a type associated with epidermodysplasia verruciformis (EV) and only weakly related to other EV-specific HPVs (1989)

The cloning and partial characterization of the genome of human papillomavirus type 50 is presented. Alignment of the genomic map with that of human papillomavirus type 5, with which it is only weakly related, was permitted by partial DNA sequence analysis.
System and Method for Separation of Crude or Hydrocarbon Free and/or Disperse in Water (2001)

Abstract The present paper relates to a system and a method for separating a hydrocarbon containing material such as crude oil from water. The system of the present paper includes a treatment tank, a layer of a fluid having a chemical affinity for the hydrocarbon contain material being separated within the tank, for separating the hydrocarbon containing material from water without any mixing device and with a minimum level of turbulence. A distribution system for introducing the water with the hydrocarbon into the layer of chemical affinity fluid. This paper also summarize the results of the pilot test running out with different API gravity crudes, showing the effectiveness of the chemical affinity fluid for oil content reducing, from water coming from dehydration processes
Superconducting Josephson structures with high linearity of transformation of magnetic signal into voltage (2010)

Possible approaches to the creation of Josephson superconducting circuits with a high linearity of transformation of a magnetic signal into voltage and a wide dynamic range have been described. Realization of such circuit by the creation of a special spatial inhomogeneity in chains of Josephson junctions and connection of these chains into a differential circuit has been considered. A new method for linearizing the transfer function of a single two-junction superconducting quantum interference device, which is an elementary cell of the chain, by connecting to it an additional loop playing the role of a nonlinear transformer of the magnetic flux has been described. For both approaches, the basic analytical expressions describing the synthesized circuits are presented. The data on numerical calculation and experimental measurements of samples produced on the basis of niobium technology with the critical current density of Josephson junctions of 4.5 kA/cm2 are reported. The approaches developed in the work can serve as a basis for the creation of highly efficient gigahertz superconducting amplifiers for cellular and satellite communications and can be applied for improving the characteristics of SQUID-based devices.
Endoscopic photoacoustic microscopy (2009)

We present a concept and system implementation for endoscopic photoacoustic microscopy that enables minimally invasive diagnosis of internal organs. The system incorporates an in-house made single element ultrasonic transducer for photoacoustic signal detection and an optical fiber for light delivery into a tubular probe with a mechanical scanning unit. The implemented probe size for the distal end is 4.2 mm in diameter and 48 mm in length. We evaluated the system's performance by imaging a carbon fiber in clear and turbid media. We also demonstrated its ability to image actual biological tissues and its endoscopic applicability, by imaging abdominal surfaces and a large intestinal tract of a rat ex vivo. This study shows the system's potential for in vivo optical biopsy of tissue abnormalities, such as tumors, developed in internal organs.
Wide-field stabilized Doppler flowmetry with the tracking scanning laser ophthalmoscope (TSLO) (2004)

Real time, high-speed image stabilization with a retinal tracking scanning laser ophthalmoscope (TSLO) enables new approaches to established diagnostics. Large dynamic range, wide-field stabilized Doppler flowmetry imaging was demonstrated in initial human subject testing with a large frequency range and up to 40 deg fields of view. The retinal tracking system uses a confocal reflectometer with a closed loop optical servo system to lock onto features in the ocular fundus. The fundus imaging method is a quasi-confocal line-scanning laser ophthalmoscope (LSLO). By locking to the retina and performing a slow scan of the laser line imager taking up to 30 seconds, frequency-resolved retinal perfusion and vascular flow images were obtained. The tracking system and auto-relock algorithms after blinks allowed the full image to be captured free of eye motion artifacts. Image cubes comprised of 512 by 512 spatial pixels by 512 or more temporal pixels were captured with a line rate of up to 20 kHz. The line sensor integrates, as opposed to conventional SLO flowmeters, thus minimizing aliasing that contributes to velocity errors. Fast Fourier Transform (FFT) power spectra at each image pixel were computed. Image reconstruction accuracy was typically better than one pixel width. Doppler frequency resolution from 14 Hz to 3.675 kHz was demonstrated in this work. Pulsatile flow effects were observed. Normal adult subjects and patients were tested with or without mydriasis to characterize flow imaging performance.
Asymmetric loss-induced perfect sound absorption in duct silencers (2020)

We investigate a duct silencer consisting of coupled resonators for perfect sound absorption. The device is composed of pairs of compact, ring-shaped Helmholtz resonators stacked along a duct. To study the effect of asymmetric intrinsic losses on the absorption performance, the resonators within each pair have the same dimensions (i.e., the identical resonance) but with different intrinsic losses. We find that the perfect absorption is realized by carefully choosing asymmetric intrinsic losses to the coupled resonators within each pair. The device with optimized losses exhibits exceptional point-like characteristics. This study provides not only a solution for practical duct systems but also allows thorough understanding of the role of asymmetric loss in degenerate resonators.
Asynchronous Acoustic Echo Cancellation Over Wireless Channels (2021)

We introduce a novel acoustic echo cancellation framework for systems where the loudspeaker and the microphone array are not synchronized. We consider the problem in the most general form where the loss of synchronization is time-varying. The proposed system is linear and it utilizes microphone array beamforming for echo cancellation. It is shown to provide significant improvement over standard echo cancellation and noise suppression techniques in both noise suppression and speech recognition.
Serodiagnosis of Recently Acquired <i>Toxoplasma gondii</i> Infection with a Recombinant Antigen (2000)

A portion of a cDNA encoding a 35-kDa antigen from Toxoplasma gondii was cloned into the CKS expression vector and expressed in Escherichia coli. By using the enzyme-linked immunosorbent assay (ELISA), the recombinant protein (rP35 antigen) was examined for reactivity with immunoglobulin G (IgG) antibodies in the sera of pregnant women. Of these women, 41 had a toxoplasma serologic profile suggestive of recently acquired T. gondii infection (Sabin-Feldman dye test [DT] titers from 1:256 to 1:32,000, positive IgM ELISA titers from 2.3 to 9.7, positive IgA ELISA from 1 to >28, and acute patterns in the differential agglutination [AC/HS] test) (group I), and 50 women had a toxoplasma serologic profile suggestive of infection acquired in the distant past (low DT titers from 1:16 to 1:512, negative IgM ELISA titers from 0 to 0.8, and chronic patterns in the AC/HS test) (group II). The classification of acute or chronic profile was based on the individual's clinical history as well as the combination of the results of the toxoplasma serological profile. An additional group (group III) was composed of sera from 50 women who were seronegative for T. gondii antibodies in the DT. The results revealed that whereas 85.3% of women in group I had IgG antibodies that reacted with the rP35 antigen, only 8% of women in group II had IgG antibodies that reacted with the same antigen. In immunoblots, the rP35 antigen was recognized by IgG antibodies in a pool of sera from individuals with a toxoplasma serologic profile compatible with acute infection but not in a pool of sera from individuals with a serologic profile characteristic of a chronic infection. These results reveal that IgG antibodies against the P35 antigen are produced during the acute stage of the infection but are uncommon in the latent or chronic phase of the infection. Thus, the rP35 antigen may be a useful serologic marker to differentiate between recently acquired infection and that acquired in the more distant past.
Induction of Protective Immunity against<i>Schistosoma mansoni</i>via DNA Priming and Boosting with the Large Subunit of Calpain (Sm-p80): Adjuvant Effects of Granulocyte-Macrophage Colony-Stimulating Factor and Interleukin-4 (2003)

Considerable morbidity and mortality result from schistosomiasis, an affliction affecting an estimated 200 million people. Although schistosomicidal drugs and other control measures (including public hygiene and snail control) exist, the advent of an efficacious vaccine remains the most potentially powerful means for controlling this disease. We have targeted a vaccine candidate (large subunit of calpain, Sm-p80) because of its consistent immunogenicity, protective potential, and integral role in surface membrane biogenesis of schistosomes. Since surface membrane renewal appears to be one of the major phenomena employed by schistosomes to evade the host's immune system; an immune response directed against Sm-p80 should render the parasite susceptible to immune clearance from the host by both providing a focus of attack and by potentially impairing the membrane repair process. In the present study, we have employed DNA immunization protocols using Sm-p80 with plasmids encoding granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4). Sm-p80 by itself provided 39% protection (P = < or =0.0001) against challenge infection in C57BL/6 mice. This protection was increased to 44% (P = < or =0.0001) when the plasmid encoding GM-CSF was coadministered with Sm-p80 DNA. Coinjection of plasmid DNA encoding IL-4 with Sm-p80 DNA yielded a protection level of 42% (P = < or =0.0001). Statistically, the protection conferred by including GM-CSF, but not IL-4, was significantly greater than that when only Sm-p80 was used. Sm-p80 DNA by itself elicited strong responses that include IgG2A and IgG2B antibody isotypes. The introduction of GM-CSF DNA with Sm-p80 DNA led to distinct increases in total IgG and IgG1 titers, whereas the coadministration of IL-4 DNA with Sm-p80 DNA resulted in a slight elevation of IgG1 and IgG3 titers and in some reduction of IgG2A and IgG2B titers. Our data again indicate that Sm-p80 can be an excellent candidate for a schistosomiasis vaccine.
Effect of Thermal Annealing on Polymer Light-Emitting Diodes Utilizing Cationic Conjugated Polyelectrolytes as Electron Injection Layers (2010)

The effect of thermal annealing on the performance of polymer light-emitting diodes (PLEDs) with a cationic conjugated polyelectrolyte as an electron injection layer is investigated. Thermal annealing at 180 °C leads to the loss of ionic content via Hofmann elimination and, hence, increases the device turn-on voltage. The ability to reduce the ionic charge density opens opportunities to design experiments for disentangling the operating mechanism for the reduction of electron injection barriers in PLEDs.
Total Nitrogen Oxides Gas Sensor Based on Solid Electrolytes with Refractory Oxide-Based Auxiliary Electrode (2004)

A new type of total nitrogen oxides gas sensor was fabricated by the conjunction of trivalent aluminum cation and divalent oxide anion conducting solid electrolytes with potassium nitrite-doped rare earth oxide-based auxiliary electrode. The sensor response was rapid, reproducible, and a continuous response was obtained. The sensor's electromotive force output is equivalent in both NO and detection with obeying the Nernst relationship, indicating that a quantitative total (NO plus gases) gas detection can be successfully realized. © 2004 The Electrochemical Society. All rights reserved.
Long-Term Prediction of Lane Change Maneuver Through a Multilayer Perceptron. (2020)

Behavior prediction plays an essential role in both autonomous driving systems and Advanced Driver Assistance Systems (ADAS), since it enhances vehicle's awareness of the imminent hazards in the surrounding environment. Many existing lane change prediction models take as input lateral or angle information and make short-term (<5 seconds) maneuver predictions. In this study, we propose a longer-term (5~10 seconds) prediction model without any lateral or angle information. Three prediction models are introduced, including a logistic regression model, a multilayer perceptron (MLP) model, and a recurrent neural network (RNN) model, and their performances are compared by using the real-world NGSIM dataset. To properly label the trajectory data, this study proposes a new time-window labeling scheme by adding a time gap between positive and negative samples. Two approaches are also proposed to address the unstable prediction issue, where the aggressive approach propagates each positive prediction for certain seconds, while the conservative approach adopts a roll-window average to smooth the prediction. Evaluation results show that the developed prediction model is able to capture 75% of real lane change maneuvers with an average advanced prediction time of 8.05 seconds.
Effects of Particle Shapes on Magnetic Properties of Compressed Cores with Fe-Si-Al Atomized Powders. (2002)

Powder cores made with Fe-Si-Al alloys, Mo-permalloy and so on are widely used for smoothing and boost choke coils of switching regulators and DC-DC converters. High permeability at DC bias magnetic field is required to be high performance and miniaturization of these magnetic cores. In this study effects of particle shapes on magnetic properties of compressed powder cores with Fe-Si-Al modified water-atomized powders were investigated. We concluded as follows. (1) Initial permeability and DC bias characteristics continuously change with particle shapes. Cores with elliptical shaped (large aspect ratio) powders exhibited high initial permeability but inferior DC bias characteristics. While with spherical shaped (small aspect ratio) powders, initial permeability was relatively low, but the permeability at high DC bias magnetic field was higher than that of elliptical shaped powders. (2) Differences of initial permeability with particle shapes can be explained by the differences of effective demagnetizing factors N of the particles through the analysis using Ollendorf 's equation. It is guessed that in case particles have large aspect ratios, they have small N, consequently initial permeability is high. Furthermore from the estimation of N, the core is magnetized connecting about four particles. (3) Permeability depends on not only particle shape of powder but also relative density of core. Using of spherical shaped particles rather than elliptical and higher density result in both high initial permeability and excellent DC bias characteristics.
Toward an Understanding of the Formation of Conducting Polymer Nanofibers (2008)

Introducing small amounts of additives into polymerization reactions to produce conducting polymers can have a profound impact on the resulting polymer morphology. When an oligomer such as aniline dimer is added to the polymerization of aniline, the nanofibers produced are longer and less entangled than those typically observed. The addition of aniline dimer can even induce nanofiber formation under synthetic conditions that generally do not favor a nanofibrillar morphology. This finding can be extended to both the synthesis of polythiophene and polypyrrole nanofibers. The traditional oxidative polymerization of thiophene or pyrrole only produces agglomerated particles. However, when minute amounts of thiophene or pyrrole oligomers are added to the reaction, the resulting polymers possess a nanofibrillar morphology. These results reveal important insights into a semirigid rod nucleation phenomenon that has hitherto been little explored. When polyaniline nucleates homogeneously, surface energy requirements necessitate the formation of ordered nuclei which leads to the directional polymerization of aniline. This ultimately leads to the one-dimensional nanofibrillar morphology observed in the final product. The synthetic procedures developed here are simple, scalable, and do not require any templates or other additives that are not inherent to the polymer.
System identification of the human vestibulo-ocular reflex during head-free tracking (2004)

A method was developed to identify the linear, system level dynamics of the horizontal, angular vestibulo-ocular reflex (VOR) as it stabilized vision during head-free tracking of a visual target. Small amplitude, broad spectrum, stochastic torque perturbations were applied to the head while the subject tracked an unpredictable, moving target with active head and eye motions. Stochastic system identification techniques were used to design the torque and target inputs and to conduct the analysis such that the linear dynamics of the VOR, independently of the visual system's influence on eye motions, were determined. The linear analysis was limited to evaluating VOR dynamics from approximately 0.5 to 4.5 Hz. Nonlinearities in the head-neck system affected the low frequency response of the head to the torque perturbations, and the eye velocity sequence was affected by nonlinearities and degraded by noise at high frequencies. The VOR's gain was near 1.0 between about 0.5 and 2.5 Hz, and then decreased steadily to 0.85 as the frequency increased towards 4.0 Hz. The VOR phase angle was also frequency dependent and corresponded to VOR eye motions lagging the head's disturbance motion by less than 10 ms at frequencies greater than 1.0 Hz.
Simulation Analysis of a New Temperature Control Method for Poultry Housing (1995)

A new control method for temperature control is presented which utilizes both a time-integrated value (TIV) and an instantaneous value of inside air temperature as the basis for making control decisions. Current control strategies neglect the thermal history of both the air space and the animal but there are gains to be made by using a control algorithm that employs dynamic control of the target control variable. It is demonstrated that increased economic efficiency is obtained using time-integrated control. Simulation analysis was used to predict energy savings and changes in bird performance for a series of TIV control algorithms. On the basis of these simulations, it was concluded that the TIV control strategy imporoved net returns compared with those obtained using a conventional control strategy. TIV control targets for temperature should be selected to reduce excessive fan usage and to prevent any mortality if at all possible. The economic parameters assumed for feed cost and meat value have a large impact on the selection of an optimal control strategy.
Carbon Nanohoops (2009)

The first synthesis of [9]-, [12]-, and [18]cycloparaphenylenes is reported. These novel compounds contain strained aromatic systems with radially oriented p-orbitals. Moreover, these compounds can be viewed as subunits of carbon nanotubes, and therefore represent a ”first step" towards fully synthetic carbon nanotubes.
Synthesis and Characteristics of a Phase‐Change Magnetic Material (2008)

A phase-change magnetic material is synthesized by doping the known GeSbTe phase-change material with Fe, and its properties are compared with the parent chalcogenide material (see figure). Besides different optical (reflectivity) and electrical properties in the amorphous and crystalline states, its magnetic properties are different in the two states; a fact that can be used to realize the fast control of ferromagnetism by phase change.