gebhart/patrepeval huggingface dataset:
Computer Modelling of Heat Transfer through Rigid Polyurethane Foam (1990)

In order to meet new demands for reduction in energy consumption for the appliance and building applications, there is an urgent need for the develop ment of rigid closed celled polyurethane foams with improved insulation properties. Furthermore, in view of the fact that chlorofluorocarbons (CFCs) have been iden tified as important potential contributors to the processes which cause a depletion of the ozone layer, there is, at the same time, a strong need to find viable alternatives to the use of CFCs, e.g., Freon™* -11 as blowing agents.
Optical communications using synchronized hyperchaos (2003)

We report experiments in which chaos in wavelength, rather than in intensity, is advantageously used to encrypt signals. The latter are encrypted as chaotic fluctuations of the wavelength of a tunable semiconductor laser driven by a generator of chaos. Decoding makes use of another generator of chaos operating as a local oscillator synchronized on the first one. The first results are reported in the wavelength range of 1550 nm. We report a specific implementation of a high dimensional chaotic system for optically encoded communications. It is achieved with a delayed feedback chaotic generator, which is known to produce high dimensional chaos. Since there is no rigorous analysis for synchronization of delay-differential equations, we used a way different from Pecora and Carroll (1991). Another originality of the method is that the method is based on chaos in wavelength, in contrast with previous systems which make use of chaos in intensity. The advantage is that the chaotic regime can be controlled very easily using a nonlinearity in wavelength rather than in power.
An Optomechanical Transducer Platform for Evanescent Field Displacement Sensing (2014)

We demonstrate an integrated waveguide platform and optomechanical transduction circuit for chip-scale displacement sensing. The waveguide consists of a thin silicon nitride core layer, a thick silicon oxide bottom cladding, and a top air cladding with a large evanescent field at the waveguide surface. Although the structures feature subwavelength (<;λ/4n <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">core</sub> ) vertical confinement, they are fabrication tolerant with micrometer-scale lateral features. We demonstrate via simulations and measurements that the waveguides exhibit a low confinement with a maximized evanescent field as well as an effective index only slightly larger than the SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> bottom cladding index. Despite the low confinement, the waveguide platform enables complex photonic circuits. As a demonstration of this technology, we fabricate and characterize an unbalanced Mach-Zehnder interferometer for chip-scale displacement sensing. A micrometer-scale fiber taper interacts with the waveguide's evanescent field and induces a phase shift proportional to displacement, thereby acting as an optomechanical transducer. We analyze the responsivity, displacement limit of detection, and strength of optomechanical coupling for high-resolution sensing. An outlook toward other applications is also given.
Role of Micro-RNAs in Regulation of Lentiviral Latency and Persistence (2006)

Small interfering RNAs have been demonstrated to serve as a molecular defence against numerous retroviruses in plants and insects and, more recently, in primates. With the recent findings of micro-RNAs (miRNAs) that seem to play a pivotal role in the survival of the host, we have explored the role of miRNAs in lentiviral (LV) replication. We have previously hypothesized that, at least in the case of lentivirus infection, small interfering RNAs are involved in the inhibition of these types of viruses by the formation of intramolecular triplex formation (triplexes) between the polypurine tracks sequences of LV provirus and miRNAs and blocking the viral replication at the preintegration complex levels, placing these viruses into a suspended latency. Using several latently and chronically infected LV cell lines and human PBMCs from HIV–1-infected individuals, we show that perinuclear triplexes are formed in LV-infected cells. The number of triplexes decreased in cells with productive replication of LVs. Therefore, the degree of replication of HIV-1 and other LVs, both in the HIV-1 or other LV-infected cell lines and the HIV-1 infected PBMCs, inversely correlate with the number of cytoplasmic triplexes present in a particular cell. This correlation was further confirmed by the stimulation of PBMCs and LV-infected cell lines with appropriate mitogens. Treatment with Tagetin, a RNA polymerase III inhibitor, resulted in a significant decrease in triplexes and a dramatic increase in the LV replication. Our data suggest that triplex formation may be an important mechanism of LV latency mediated by endogenous miRNAs.
Comparison of myocardial motion estimation methods based on simulated echocardiographic B-mode and RF data (2010)

In this paper, we combine a ventricular kinematic model and an ultrasound simulation model in order to simulate the echocardiographic imaging process. In addition to its capability to generate raw RF data, when compared to previous echocardiography simulation models, the result achieves more realistic B-Mode images. Several echocardiography parameters were taken into account including central frequency, apodization, number of elements in the array, speed of sound, and number of scatterers. The proposed improvements are due to the use of a shift-variant Point Spread Function (PSF) and more accurate cardiac motion assumptions. One attribute of the simulator is also that it provides the groundtruth vector field of actual "ventricular deformations'' which may be used to strictly validate motion estimation and myocardial elastography algorithms. The paper presents the first application of optical flow to normalized data in piece-wise segments of RF images. Different optical flow motion estimation techniques such as Lucas-Kanade, Horn-Schunck, Brox et al., Black and Anandan, and Block Matching (BM) were applied to the simulated B-mode images and RF data. The estimated motion fields from the RF data as well as the B-mode images were validated with the ground-truth motion fields derived from the simulator. The validation results show that the Brox et al. method performs better than other motion estimation techniques when applied to B-Mode and RF data. Also, as intuitively expected, use of RF data results in more accurate displacement fields than when B-mode images alone are used.
Synthesis of novel 1‐phenyl‐1<i>H</i>‐indole‐2‐carboxylic acids. <b>II.</b> Preparation of 3‐dialkylamino, 3‐alkylthio, 3‐alkylsulfinyl, and 3‐alkylsulfonyl derivatives (1987)

Abstract The synthesis of novel indole‐2‐carboxylic acids with amino‐ and sulfur‐containing substituents in the indole 3‐position is described. An Ullmann reaction with bromobenzene converted 1 H ‐indoles with 3‐(acetylamino)‐ and 3‐(diethylamino)‐substituents into 1‐phenyl‐1 H ‐indoles. Reaction of 3‐unsubstituted indoles with thionyl chloride provided indole 3‐sulfinyl chlorides, which reacted with alkyl and aryl Grignard reagents to form the corresponding sulfoxides. The indole sulfoxides thus obtained were reduced to sulfides or oxidized to sulfones.
Synthesis and characterization of novel thermoplastic elastomers incorporating tailored temperature switching hard blocks (1993)

This paper reports the synthesis and characterization of a novel class of thermoplastics elastomers (TPEs) that exhibit a unique temperature switching property that is variable over a broad temperature range due to the choice of hard block components. The hard blocks are crystalline polymers or oligomers from a family known as side chain crystalline (SCC) polymers, referred as the Intelimers{sup R} at Landec Corporation when thermal transitions are accurately controlled over the technique range of 0 to 100-{degrees}c. Attachment of these SCC polymer or oligomers to soft or low Tg noncrystalline blocks results in thermoplastic elastomers where the macroscopic viscous flow property can be accurately switched from a rubbery two phase solid to a viscous fluid at a controlled specific temperature. Rheological evaluations show a dramatic complex modulus decrease within 10{degrees}C of the DSC endotherm peak. Physical and mechanical properties of the TPEs were evaluated with calcium carbonate filler.
Particle impact probe (1990)

The Morgantown Energy Technology Center has been developing an instrumentation system to monitor the dynamic behavior of particles in fluidized beds with minimum disturbance of particle motion. During the first phase of development, a particle impact probe and a supporting electronic system have been designed. This probe and electronic system show capabilities for measuring the x, y, and z components of momentum transferred to the probe head by individual particle impacts and for measuring the x, y, and z components of solids force exerted on the probe head in dense fluidized beds. The prototype probe had an 0.125-in. diameter stainless steel tube base with an 0.125-in. diameter nylon sphere probe head mounted at one end. When impacted by particles, the probe head produced motion in a miniature electrode system mounted within the tube base. The signals produced by the electrode system were calibrated to produce either the components of the momentum vector of the probe head during individual particle impacts or the components of the force exerted on the probe head during multiple, closely spaced particle impacts. Researchers expect to make a miniature probe and increase its sensitivity and accuracy. 7 refs., 15 figs.
A Fast and Accurate Far-Field Pseudopolar Format Radar Imaging Algorithm (2009)

A novel imaging algorithm to be used under the condition of having an image scene in the far field of a linear radar aperture is presented. This is an application scenario that is drastically different from those of spaceborne and airborne synthetic aperture radar (SAR) systems, which has not been properly addressed to date. The technique is particularly tailored for a stepped-frequency continuous wave (CW) or frequency-modulated CW radar. The radar aperture must be linear and can be formed either with a physical or synthetic array. With the suggested method, the radar reflectivity of the image scene is obtained through an interpolation-free series expansion, where only 2-D fast Fourier transforms of the frequency-domain backscatter data are required. The resulting image is sampled on a ldquopolarlikerdquo or pseudopolar grid, which is introduced to simplify the formulation. The main advantages of this method are its extremely low computational cost and the high accuracy of the resulting imagery. The technique is extensively validated both with numerical simulations and two ground-based SAR data sets. Last but not least, numerical simulations show that this technique can be used with an ultrawideband radar of 1 GHz of bandwidth.
Impact of electrode placement and configuration on performance of morphological measures of intraventricular electrograms (2003)

The authors assess the effect of position of the catheter electrodes on morphology analysis is both unipolar and bipolar configuration. Unfiltered bipolar and unipolar intraventricular electrograms were recorded from an electrode catheter initially positioned in the right ventricular (RV) apex (site 1) of 13 patients during sinus rhythm and induced monomorphic ventricular tachycardia (VT). Sinus rhythm and the identical VT were recorded a second time after repositioning the same electrode catheter within the RV apex (site 2) 0.2-4.4 cm from its original site. Analysis of unipolar electrograms detected 10/10 VTs at both sites, whereas analysis of bipolar electrograms detected 8/10 VTs at site 1 and 9/10 VTs at site 2, but was successful in all ten using a choice of either site 1 or 2. Thus, unipolar electrogram analysis for VT detection is less affected than bipolar electrogram analysis by a change in electrode catheter position but bipolar electrograms can be equally effective with a careful and judicious choice of electrode placement.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
How to Optimize the Quality of Sensor Data Streams (2009)

Present data stream management systems allow the automatic recording and processing of huge data volumes to guide any kind of process control or business decision. However, a crucial problem is posed by data quality deficiencies due to imprecise sensors, environmental influences, transfer failures, etc. If not handled carefully, they lead to misguided decisions and inappropriate actions. In this paper, we present the quality-driven optimization of stream processing to improve the resulting quality of data and service. First, we present the optimization objectives and discuss the parameterization of stream processing operators to define the underlying optimization problem. We develop the generic optimization framework and present the quality-driven evolution strategy (QES). Finally, we show that the designed optimization scales very well with regard to processing complexity and reduces numerical errors in the contact lens production monitoring.
Preliminary examination of the Linear Free-Electron Laser (1979)

The Linear Free Electron Laser is numerically analyzed in the one dimensional limit by following an average (resonant) particle. Several different wiggler schemes are presented, and electron beam current density requirements are discussed. A variable phase angle buncher is also proposed.
Rationale and prospects for novel pneumococcal vaccines (2015)

Streptococcus pneumoniae remains one of the most frequent bacterial causes of morbidity and mortality worldwide. National immunization programs implementing pneumococcal polysaccharide conjugate vaccines (PCVs) have successfully reduced rates of vaccine-type invasive disease and colonization both via direct effects in immunized children and, in some settings, indirect effects in unimmunized individuals. Limitations of the current PCV approach include the emergence of non-vaccine serotypes contributing to carriage and invasive disease in high-PCV coverage settings and the high cost of goods of PCVs which limits their accessibility in developing countries where the burden of disease remains highest. Furthermore, the distribution of serotypes causing disease varies geographically and includes more serotypes than are currently covered in a single PCV formulation. Researchers have long been exploring the potential of genetically conserved non-capsular pneumococcal antigens as vaccine candidates that might overcome such limitations. To better evaluate the rationale of such approaches, an understanding of the mechanisms of immunity to the various phases of pneumococcal infection is of paramount importance. Herein we will review the evolving understanding of both vaccine-induced and naturally acquired immunity to pneumococcal colonization and infection and discuss how this informs current approaches using serotype-independent pneumococcal vaccine candidates. We will then review the alternative vaccine candidates that have been or are currently under evaluation in clinical trials.
Deep Context Maps: Agent Trajectory Prediction Using Location-Specific Latent Maps (2020)

In this letter, we propose a novel approach for agent motion prediction in cluttered environments. One of the main challenges in predicting agent motion is accounting for location and context-specific information. Our main contribution is the concept of learning context maps to improve the prediction task. Context maps are a set of location-specific latent maps that are trained alongside the predictor. Thus, the proposed maps are capable of capturing location context beyond visual context cues (e.g. usual average speeds and typical trajectories) or predefined map primitives (such as lanes and stop lines). We pose context map learning as a multi-task training problem and describe our map model and its incorporation into a state-of-the-art trajectory predictor. In extensive experiments, it is shown that use of learned maps can significantly improve predictor accuracy. Furthermore, the performance can be additionally boosted by providing partial knowledge of map semantics.
Extracting anchorable information units from PDF files (2003)

Document processing and understanding is important for a variety of applications such as office automation, creation of electronic manuals, online documentation and annotation etc. The first step towards this process often involves the extraction of relevant keywords and phrases from the documents so that they can be automatically hyperlinked within and outside the document so that we can create an electronic document. This paper describes a novel method for extracting anchorable information units (AIUs), also known as hotspots from any type of portable document format (PDF) files, which may either be created using either an editor or by scanning in documents. The AIUs are used to make these documents more intelligent for content cross-referencing to/from related multimedia documents within an electronic document publishing environment. Domain specific knowledge about the documents are used to aid the extraction process. Once the location and extent of the texts are found, the content is extracted through the use of an optical character recognition (OCR) software if necessary. For the case of object extraction for highlighting, first the images are extracted and then a variety of image processing algorithms are applied.
Experimental demonstration of a high quality factor photonic crystal microcavity (2003)

Subthreshold measurements of a photonic crystal (PC) microcavity laser operating at 1.3 μm show a linewidth of 0.10 nm, corresponding to a quality factor (Q)∼1.3×104. The PC microcavity mode is a donor-type mode in a graded square lattice of air holes, with a theoretical Q∼105 and mode volume Veff∼0.25 cubic half-wavelengths in air. Devices are fabricated in an InAsP/InGaAsP multi-quantum-well membrane and are optically pumped at 830 nm. External peak pump power laser thresholds as low as 100 μW are also observed.
Antibody Responses to Norovirus Genogroup GI.1 and GII.4 Proteases in Volunteers Administered Norwalk Virus (2012)

An assay was developed to detect antibodies against two norovirus proteases among participants in a Norwalk virus (GI.1) challenge study. Prechallenge seroprevalence was lower against the protease from the homologous GI.1 virus than against protease from a heterologous GII.4 strain. Seroresponses were detected for 14 of 19 (74%) infected persons.
Exploring Event Camera-based Odometry for Planetary Robots (2022)

Due to their resilience to motion blur and high robustness in low-light and high dynamic range conditions, event cameras are poised to become enabling sensors for vision-based exploration on future Mars helicopter missions. However, existing event-based visual-inertial odometry (VIO) algorithms either suffer from high tracking errors or are brittle, since they cannot cope with significant depth uncertainties caused by an unforeseen loss of tracking or other effects. In this work, we introduce EKLT-VIO, which addresses both limitations by combining a state-of-the-art event-based frontend with a filter-based backend. This makes it both accurate and robust to uncertainties, outperforming event- and frame-based VIO algorithms on challenging benchmarks by 32%. In addition, we demonstrate accurate performance in hover-like conditions (outperforming existing event-based methods) as well as high robustness in newly collected Mars-like and high-dynamic-range sequences, where existing frame-based methods fail. In doing so, we show that event-based VIO is the way forward for vision-based exploration on Mars.
A High-Frequency Inverter for Variable-Load Operation (2019)

This paper presents a new inverter architecture suitable for driving widely varying load impedances at high frequency (HF, 3-30 MHz) and above. We present the underlying theory and design considerations for the proposed architecture along with a physical prototype and efficiency optimizing controller. The HF variable-load inverter (HFVLI) architecture comprises two HF inverters with independently controllable amplitude and phase connected together and to the load via a lossless power combining network, implemented here as an immittance converter. By controlling the amplitudes and relative phase of the two constituent inverters, the loading seen by each constituent inverter can be kept in a desirable range even for wide variations in load impedance. This allows for the use of highly efficient zero-voltage switching inverters that would otherwise be precluded or limited in applications presenting wide impedance ranges, such as wireless power transfer and RF plasma generation. The prototype HFVLI system demonstrates the benefits of the proposed approach. It operates at 13.56 MHz and can supply a maximum output power of 1 kW into a 21.8 + 0.3j load at an efficiency of 95.4% and is able to drive a wide range of capacitive and inductive loads at high power with high efficiency.
Detection and enumeration of single nanometric particles: A confocal optical design for fluorescence flow cytometry (2002)

Nanometer-sized particles are increasingly important in fields ranging from technology development to environmental analysis. Traditionally, quantification of biological nanometric particles, such as viruses, has been challenging. Recent advances in optics and optical design have made single molecule detection possible in flowing systems. However, many commercially available flow cytometers are not optimized for routine analysis of ultrasmall biological particles. In this work, a confocal optical arrangement was incorporated into the design of a relatively simple flow cytometer optimized for rapid enumeration of fluorescent nanometric particles. The instrument was designated the “single nanometric particle enumerator” (SNaPE). Instrument parameters, such as data acquisition rates, flow rates, and minimum sampling time were examined and optimized for the SNaPE. The measured detection efficiency was ∼8%, which is consistent with the confocal geometry and equivalent to the detection efficiency reported in many single molecule studies. Signal calibration was achieved using fluorescent polystyrene spheres ranging from 26 nm to 10 μm in diameter. The SNaPE exhibited a limit of detection of ∼180 fluorescein isothiocyanate equivalents and was capable of particle enumeration over the tested concentration range of 106–109 particles/ml.
Magnetic modulation of gain in a chemical oxygen-iodine laser (1991)

A magnetic modulation of gain in a continuous-wave (CW) chemical oxygen-iodine laser (COIL) is proposed for several regimes of laser generation. The principle of the method proposed is based on a direct magnetic modulation of gain in the active zone of a COIL utilizing the Zeeman effect on the laser transition /sup 2/P/sub 1/2/-/sup 2/P/sub 3/2/ of iodine atoms. The possible applications of this technique to control the laser generation in COIL for technological purposes are outlined.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>