gebhart/patrepeval huggingface dataset:
Numerical Analysis of Welding Phenomena in High-Frequency Electric Resistance Welding (2014)

High-frequency electric resistance welded pipes are used for high-grade line pipes. To address the significant need for weld seam reliability, it is important to clarify the associated welding phenomena. In this study, a numerical analysis model is developed to clarify the behaviours of the molten steel and oxide in HFW pipes. The temperature distribution of the HFW is calculated using electromagnetic and heat conductive finite element analysis methods. The molten metal and oxide flows are analysed by modelling heat conductive and plastic flows. The movement behaviour of the oxides in the molten steel is successfully analysed with this technique. The material properties as a function of the temperature of the steel pipe are calculated using general-purpose simulation software. With pressurisation by the welding rolls, the molten steel moves to the upper part, and the oxide, which exists in the internal parts, rapidly decreases such that almost all of the oxide transitions to the excess metal part. The internal oxide content rate after pressurisation at 0.08 m/s is less than 0.01. To decrease the oxide content, the pressurisation rate must increase such that the molten steel and an oxide pressurised at high temperatures transition to the excess metal part.
Real-time compression of raw computed tomography data: technology, architecture, and benefits (2009)

Compression of computed tomography (CT) projection samples reduces slip ring and disk drive costs. A lowcomplexity, CT-optimized compression algorithm called Prism CT<sup>TM</sup> achieves at least 1.59:1 and up to 2.75:1 lossless compression on twenty-six CT projection data sets. We compare the lossless compression performance of Prism CT to alternative lossless coders, including Lempel-Ziv, Golomb-Rice, and Huffman coders using representative CT data sets. Prism CT provides the best mean lossless compression ratio of 1.95:1 on the representative data set. Prism CT compression can be integrated into existing slip rings using a single FPGA. Prism CT decompression operates at 100 Msamp/sec using one core of a dual-core Xeon CPU. We describe a methodology to evaluate the effects of lossy compression on image quality to achieve even higher compression ratios. We conclude that lossless compression of raw CT signals provides significant cost savings and performance improvements for slip rings and disk drive subsystems in all CT machines. Lossy compression should be considered in future CT data acquisition subsystems because it provides even more system benefits above lossless compression while achieving transparent diagnostic image quality. This result is demonstrated on a limited dataset using appropriately selected compression ratios and an experienced radiologist.
Automated analysis of normal and glaucomatous optic nerve head topography images. (2000)

ONH images can be classified objectively and dependably by an automated procedure that does not require prior manual outlining of disc boundaries.
Synthesis of Poly(phenylenes) by a Rapid Polymerization of 1-Bromo-4- lithiobenzene Using HMPA (1991)

Abstract : A synthesis of poly(phenylene) is described by the treatment of 1- bromo-4-lithiobenzene with hexamethylphosphoramide (HMPA). The polymerization occurred nearly instantaneously even at -78 C. Conditions have been optimized using dioxane as a solvent and HMPA addition at 70 - 80 C to afford poly(phenylenes) that are predominantly para - linked. The polymers are soluble in THF, dichloromethane, and chloroform. Analysis of the initially formed polymers showed that there was a high bromide content (approximately one bromide for every three aryl rings). Debromination of the material was achieved by treatment with butyllithium and quenching with water. The Mw of the debrominated polymer was 3178 by SEC analysis.
Cosmic ray muon tomography system using drift chambers for the detection of Special Nuclear Materials (2010)

The smuggling of illicit Special Nuclear Materials (SNM) and Radiological Materials (RM) is a major security concern. Current radiation detection systems for cargo are not sensitive to well-shielded nuclear materials. The Muon Scattering Tomography (MST) method that we are developing might be a solution to this problem. It is based on the measurement of multiple scattering of cosmic ray-induced muons, traversing high-Z materials such as uranium and plutonium. This is possible due to the muons' highly penetrating nature. The technique involves measuring the angular deflections of these muons with charged particle tracking detectors placed around the object to be probed. One candidate detector is the single wire drift chamber. It can measure the 2-D impact position of a muon. The CRIPT (Cosmic Ray Inspection and Passive Tomography) collaboration has performed computer simulations of detectors designed to detect SNM via MST. We have also worked on the development of image reconstruction algorithms, and simulated the performances of different and the response of the drift chambers. In addition to these efforts, the collaboration has built three prototypes which are being tested.
Development of a Conditional Gene Expression System Using a Zearalenone-Inducible Promoter for the Ascomycete Fungus <i>Gibberella zeae</i> (2010)

The ascomycete fungus Gibberella zeae is an important plant pathogen that causes fusarium head blight on small grains. Molecular studies of this fungus have been performed extensively to uncover the biological mechanisms related to pathogenicity, toxin production, and sexual reproduction. Molecular methods, such as targeted gene deletion, gene overexpression, and gene fusion to green fluorescent protein (GFP), are relatively easy to perform with this fungus; however, conditional expression systems have not been developed. The purpose of this study was to identify a promoter that could be induced by zearalenone (ZEA) for the development of a conditional expression system in G. zeae. Through microarray analysis, we isolated one zearalenone response gene (ZEAR) whose expression was increased more than 50 times after ZEA treatment. Northern blot analysis showed that the ZEAR transcript dramatically increased after 1 h of ZEA treatment. To determine the utility of the ZEAR promoter, called Pzear, in a conditional expression system, we transformed a Pzear::GFP fusion construct into G. zeae. Our data showed a ZEA concentration-dependent increase in GFP expression. We also replaced the promoter of G. zeae metE (GzmetE), an essential gene for methionine biosynthesis, with the Pzear promoter. The growth of the Pzear-GzmetE mutant on minimal medium was dependent on the ZEA concentration supplemented in the medium and showed that GzMetE expression was induced by ZEA. This study is the first report of an inducible promoter in G. zeae. Our system will be useful for the characterization of essential gene functions in this fungus through differential and ZEA-dependent gene expression. In addition, the Pzear promoter may be applicable as a biosensor for the detection of ZEA contamination in agricultural products.
A hybrid automatic scoring system for Arabic essays (2014)

Essay writing is widely used for student performance assessment. This paper presents a hybrid automatic essay scoring system (AES) for Arabic essays. The system attempts at saving the time teachers spend on reading and scoring Arabic essays. It utili
A New Adaptive Predistortion Technique Using Software-Defined Radio and DSP Technologies Suitable for Base Station 3G Power Amplifiers (2004)

We present in this paper an advanced adaptive baseband/RF predistorter that integrates the concept of the software-defined radio technology into the power-amplifier (PA) linearization area. The linearizer performs an instantaneous characterization of the PA, using two digital receivers, in order to supply its instantaneous AM-AM and AM-PM curves. It then determines an inverse function that represents the best fit to the reciprocal of the PA behavior. Code-division multiple-access and third-generation standard signals applying different stress level on the PA are used to evaluate the performance of the linearizer. The system is validated using digital signal processing/RF co-simulation for a typical 44-dBm class-AB PA. To estimate the performance of the linearizer under realistic condition, experimental results have been carried out in open-loop condition, supported by a software-instruments connectivity, for a 20-W class-AB PA operating at 1.96 GHz. Results for different cases of standards signals reveal a significant reduction, in the order of 5 dB, in effective output power backoff.
High Lift Common Research Model for Wind Tunnel Testing: An Active Flow Control Perspective (2017)

This paper provides an overview of a research and development effort sponsored by the NASA Advanced Air Transport Technology Project to achieve the required high-lift performance using active flow control (AFC) on simple hinged flaps while reducing the cruise drag associated with the external mechanisms on slotted flaps of a generic modern transport aircraft. The removal of the external fairings for the Fowler flap mechanism could help to reduce drag by 3.3 counts. The main challenge is to develop an AFC system that can provide the necessary lift recovery on a simple hinged flap high-lift system while using the limited pneumatic power available on the aircraft. Innovative low-power AFC concepts will be investigated in the flap shoulder region. The AFC concepts being explored include steady blowing and unsteady blowing operating in the spatial and/or temporal domain. Both conventional and AFC-enabled high-lift configurations were designed for the current effort. The high-lift configurations share the cruise geometry that is based on the NASA Common Research Model, and therefore, are also open geometries. A 10%-scale High Lift Common Research Model (HL-CRM) is being designed for testing at the NASA Langley Research Center 14- by 22-Foot Subsonic Tunnel during fiscal year 2018. The overall project plan, status, HL-CRM configurations, and AFC objectives for the wind tunnel test are described.
Novel photonic filter and receiver based on Whispering Gallery Mode microresonators (2002)

We describe two new devices based on whispering gallery mode microresonators. The first device, a multipole filter, is based on coupled microresonators, the frequency of which is trimmed in situ to produce the desired filter function. The second device is based on a lithium niobate microresonator, which can detect applied microwave signals with power as low as 2.5 nW.
Tracking an RGB-D Camera Using Points and Planes (2013)

Planes are dominant in most indoor and outdoor scenes and the development of a hybrid algorithm that incorporates both point and plane features provides numerous advantages. In this regard, we present a tracking algorithm for RGB-D cameras using both points and planes as primitives. We show how to extend the standard prediction-and-correction framework to include planes in addition to points. By fitting planes, we implicitly take care of the noise in the depth data that is typical in many commercially available 3D sensors. In comparison with the techniques that use only points, our tracking algorithm has fewer failure modes, and our reconstructed model is compact and more accurate. The tracking algorithm is supported by relocalization and bundle adjustment processes to demonstrate a real-time simultaneous localization and mapping (SLAM) system using a hand-held or robot-mounted RGB-D camera. Our experiments show large-scale indoor reconstruction results as point-based and plane-based 3D models, and demonstrate an improvement over the point-based tracking algorithms using a benchmark for RGB-D cameras.
THz emitter based on InAs-GaSb coupled quantum wells: new prospects for THz photonics (2005)

We suggest a new structure for THz generation based on coupled quantum wells of InAs-GaSb. This structure uniquely combines the advantages of both the p-n junction laser and the cascade laser. Actual generation results from optical transitions between the e3 and e2 levels in InAlAs quantum well, and resonant with them effective band gap between the conduction band of InAs and the valence band of GaSb quantum well, e1-hh1. The separation between e1 and e2 equals to LO phonon energy that provides population inversion between e3 and e2. We consider two ways of structure design that differ by the carrier dispersion: W-shaped dispersion of the carriers in ground states and regular V-shaped dispersion. All these structures bring in the advantages of the system with equidistant levels, i.e., good temperature characteristics and high probability of radiative transition leading to low threshold current compared to alternative designs. We present a comparative analysis of various mechanisms of carrier relaxation (LO phonons and electron-electron scattering) and point out an optimal band structure favoring high efficiency of THz emitter. Corresponding band structure calculations supply one with the range of quantum well parameters providing all the features presented above.
Synthesis of fluorescent analogs of relaxin family peptides and their preliminary in vitro and in vivo characterization (2013)

Relaxin, a heterodimeric polypeptide hormone, is a key regulator of collagen metabolism and multiple vascular control pathways in humans and rodents. Its actions are mediated via its cognate G-protein-coupled receptor, RXFP1 although it also "pharmacologically" activates RXFP2, the receptor for the related, insulin-like peptide 3 (INSL3), which has specific actions on reproduction and bone metabolism. Therefore, experimental tools to facilitate insights into the distinct biological actions of relaxin and INSL3 are required, particularly for studies of tissues containing both RXFP1 and RXFP2. Here, we chemically functionalized human (H2) relaxin, the RXFP1-selective relaxin analog H2:A(4-24)(F23A), and INSL3 to accommodate a fluorophore without marked reduction in binding or activation propensity. Chemical synthesis of the two chains for each peptide was followed by sequential regioselective formation of their three disulfide bonds. Click chemistry conjugation of Cy5.5 at the B-chain N-terminus, with conservation of the disulfide bonds, yielded analogs displaying appropriate selective binding affinity and ability to activate RXFP1 and/or RXFP2 in vitro. The in vivo biological activity of Cy5.5-H2 relaxin and Cy5.5-H2:A(4-24)(F23A) was confirmed in mice, as acute intracerebroventricular (icv) infusion of these peptides (but not Cy5.5-INSL3) stimulated water drinking, an established behavioral response elicited by central RXFP1 activation. The central distribution of Cy5.5-conjugated peptides was examined in mice killed 30 min after infusion, revealing higher fluorescence within brain tissue near-adjacent to the cerebral ventricle walls relative to deeper brain areas. Production of fluorophore-conjugated relaxin family peptides will facilitate future pharmacological studies to probe the function of H2 relaxin/RXFP1 and INSL3/RXFP2 signaling in vivo while tracking their distribution following central or peripheral administration.
Airborne SAR processing of highly squinted data using a chirp scaling approach with integrated motion compensation (1994)

Proposes a new approach for high-resolution airborne SAR data processing, which uses a modified chirp scaling algorithm to accommodate the correction of motion errors, as well as the variations of the Doppler centroid in range and azimuth. By introducing a cubic phase term in the chirp scaling phase, data acquired with a squint angle up to 30/spl deg/ can be processed with no degradation of the impulse response function. The proposed approach is computationally very efficient, since it accommodates the variations of Doppler centroid without using block processing. Furthermore, a motion error extraction algorithm can be incorporated into the proposed approach by means of subaperture processing in azimuth. The new approach, denoted as extended chirp scaling, is considered to be a generalized algorithm suitable for the high-resolution processing of most airborne SAR systems.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
A loosely coupled capacitive power transfer system with LC compensation circuit topology (2016)

This paper proposes a double-sided LC compensated capacitive power transfer (CPT) system, which is the dual of the conventional series-series (SS) compensated inductive power transfer (IPT) system. Four metal plates are arranged as the capacitive coupler, and there are coupling capacitances between each pair of plates. At each side, a compensation capacitor is connected in parallel with the plates, and its value is usually much larger than the coupling capacitance between the plates, which results in a loosely coupled CPT system. In this paper, the fundamental harmonics approximation (FHA) method is used to analyze the circuit working principle. It shows that the system can work at constant current mode. An expression for the system output power is expressed, which is similar to that of the SS compensated IPT system. A 150W input power CPT system is therefore designed as an example to validate the compensation topology. The experimental results show that the dc to dc efficiency of the system is 66.67% when the air-gap distance is 180 mm and the switching frequency is 1.5 MHz.
Development of phase shift masks for extreme ultraviolet lithography and optical evaluation of phase shift materials (2004)

Phase Shift Masks (PSM) for Extreme Ultraviolet Lithography (EUVL) have the potential for extending the lithographic capability of EUVL beyond the 32-nm node. The concept of EUV PSM structures can be implemented either by adding absorber structures on top of the Mo/Si multilayers (additive approach) or by partial etching into the multilayers (subtractive approach). Among many technical challenges, evaluating optical constants of absorber materials is the most important issue particularly for PSM by the additive approach (PSM-ADD), while the etch stop capability and the etch selectivity with vertical sidewall profile are the main technical challenges for PSM fabricated by the subtractive method (PSM-SUB). For fast turn around of PSM development, the indirect optical constant evaluation through material analysis is a useful metrology technique. The optical constant of TaSiN extracted from Rutherford Backscattering Spectroscopy (RBS) data agrees well with that obtained from the direct measurement by transmission interferometric technique. For PSM-SUB, the concept of embedding B4C and NiFe etch stop layer (ESL) is verified by measuring reflectivity of the ESL embedded substrates and demonstrating good etch stop capability.
Crystallographic Fragment Screening and Structure-Based Optimization Yields a New Class of Influenza Endonuclease Inhibitors (2013)

Seasonal and pandemic influenza viruses continue to be a leading global health concern. Emerging resistance to the current drugs and the variable efficacy of vaccines underscore the need for developing new flu drugs that will be broadly effective against wild-type and drug-resistant influenza strains. Here, we report the discovery and development of a class of inhibitors targeting the cap-snatching endonuclease activity of the viral polymerase. A high-resolution crystal form of pandemic 2009 H1N1 influenza polymerase acidic protein N-terminal endonuclease domain (PAN) was engineered and used for fragment screening leading to the identification of new chemical scaffolds binding to the PAN active site cleft. During the course of screening, binding of a third metal ion that is potentially relevant to endonuclease activity was detected in the active site cleft of PAN in the presence of a fragment. Using structure-based optimization, we developed a highly potent hydroxypyridinone series of compounds from a fragment hit that defines a new mode of chelation to the active site metal ions. A compound from the series demonstrating promising enzymatic inhibition in a fluorescence-based enzyme assay with an IC50 value of 11 nM was found to have an antiviral activity (EC50) of 11 μM against PR8 H1N1 influenza A in MDCK cells.
P1D-1 Pulse Inversion Sequences for Mechanically Scanned Transducers (2006)

Mechanically scanned transducers are currently used for tissue harmonic imaging (THI) and nonlinear microbubble imaging at high frequencies. Pulse inversion (PI) techniques are widely used for suppression of the fundamental signal but its effectiveness is reduced by relative tissue/transducer motion. In this study we propose weighted PI-sequences that achieve a significant improvement on the fundamental suppression for acquisitions with a mechanically scanned transducer. Simulations of nonlinear Intravascular Ultrasound (IVUS) beams from a rotating transducer, show an increased fundamental suppression of up to >10 dB as compared to the basic PI technique. Application of the proposed PI-sequence on RF-data from in vivo acquisitions resulted in an extra fundamental suppression of >6 dB. The proposed PI-sequences will help to reduce relative tissue/transducer motion effects and might therefore lead to improved image quality in nonlinear tissue imaging and improved microbubble detection in contrast imaging
Magnetic resonance elastography of the brain using multishot spiral readouts with self‐navigated motion correction (2012)

Magnetic resonance elastography (MRE) has been introduced in clinical practice as a possible surrogate for mechanical palpation, but its application to study the human brain in vivo has been limited by low spatial resolution and the complexity of the inverse problem associated with biomechanical property estimation. Here, we report significant improvements in brain MRE data acquisition by reporting images with high spatial resolution and signal-to-noise ratio as quantified by octahedral shear strain metrics. Specifically, we have developed a sequence for brain MRE based on multishot, variable-density spiral imaging, and three-dimensional displacement acquisition and implemented a correction scheme for any resulting phase errors. A Rayleigh damped model of brain tissue mechanics was adopted to represent the parenchyma and was integrated via a finite element-based iterative inversion algorithm. A multiresolution phantom study demonstrates the need for obtaining high-resolution MRE data when estimating focal mechanical properties. Measurements on three healthy volunteers demonstrate satisfactory resolution of gray and white matter, and mechanical heterogeneities correspond well with white matter histoarchitecture. Together, these advances enable MRE scans that result in high-fidelity, spatially resolved estimates of in vivo brain tissue mechanical properties, improving upon lower resolution MRE brain studies that only report volume averaged stiffness values.