gebhart/patrepeval huggingface dataset:
A Reaction Mechanism for Producing Low-Friction Iron Phosphate Coatings (1991)

Engine friction reduction through lubricant modification is an appealing approach for improving vehicle fuel economy because the benefits realized can be readily applied to all vehicles. Since tribological processes are influenced by electrochemical interactions between a lubricant and the lubricated sliding surface, electrochemical techniques should be valuable in reducing engine friction. An iron phosphate reaction film has been coated on cast iron electrodes by means of electrolysis of a lubricant containing 2.5 mass percent dilauryl hydrogen phosphate (DHP or “acid phosphate”). Friction tests showed a 20 percent lower friction coefficient for iron phosphate-coated piston ring specimens in comparison to uncoated ones. Laboratory reaction studies indicated that the electrolysis process accelerated a spontaneous corrosion reaction between the electrode and the acid phosphate. Increasing either the electric field or the agitation of the lubricant also accelerated the reaction rate for iron phosphate film formation. A mechanism for the electrolysis reaction was proposed, which involves the formation of ferrous ions at the anode, and hydrogen evolution at the cathode. The consumption of hydrogen ion in producing hydrogen at the cathode enhances the dissociation of acid phosphate to form more acid phosphate anion. The phosphate anion, in turn, chemically reacts with ferrous ion to generate phosphate films on the electrodes.
A lock-free, concurrent, and incremental stack scanning for garbage collectors (2009)

Two major efficiency parameters for garbage collectors are the throughput overheads and the pause times that they introduce. Highly responsive systems need to use collectors with as short as possible pause times. Pause lengths have decreased significantly during the years, especially through the use of concurrent garbage collectors. For modern concurrent collectors, the longest pause is typically created by the need to atomically scan the runtime stack. All practical concurrent collectors that we are aware of must obtain a snapshot of the pointers on each thread's runtime stack, in order to reclaim objects correctly. To further reduce the length of the collector pauses, incremental stack scans were proposed. However, previous such methods employ locks to stop the mutator from accessing a stack frame while it is being scanned. Thus, these methods introduce a potential long and unpredictable pauses for a mutator thread. In this work we propose the first concurrent, incremental, and lock-free stack scanning for garbage collectors, allowing high responsiveness and support for programs that employ fine-synchronization to avoid locks. Our solution can be employed by all concurrent collectors that we are aware of, it is lock-free, it imposes a negligible overhead on the program execution, and it supports the special in-stack references existing in languages like C#.
Comparative analysis of collagen type II-specific immune responses during development of collagen-induced arthritis in two B10 mouse strains (2012)

The present study provides important evaluation of CII-specific immune responses at different phases during CIA development as well as a comparative analysis between two CIA mouse models. We indicate significant differences in CII T cell and antibody specificities between the two strains and highlight a need for improved humanized B10.DR4 mouse model for rheumatoid arthritis.
Linear programming based design and analysis of battery pack balancing topologies (2015)

High voltage Li-ion battery packs are typically configured in a modular fashion. In this paper, the performance of different battery pack balancing topologies is analysed at both module and cell levels. Two-level balancing topologies, including cell-to-cell balancing at intra-module level and module-to-module balancing at inter-module level, are considered in the analysis. Topologies are comprised of combinations of line shunting, ring shunting, synchronous fly-back, multi-winding, and dissipative shunting. Aspects of battery pack balancing performance, such as minimum balancing time, minimum plug-in charge time, and minimal energy loss in balancing are calculated using linear programming. Component counts of every balancing topology for the entire battery pack are also compared to assess circuit complexity.
Empowering Low-Power Wide Area Networks in Urban Settings (2017)

Low-Power Wide Area Networks (LP-WANs) are an attractive emerging platform to connect the Internet-of-things. LP-WANs enable low-cost devices with a 10-year battery to communicate at few kbps to a base station, kilometers away. But deploying LP-WANs in large urban environments is challenging, given the sheer density of nodes that causes interference, coupled with attenuation from buildings that limits signal range. Yet, state-of-the-art techniques to address these limitations demand inordinate hardware complexity at the base stations or clients, increasing their size and cost.
Stall Warning in a Low-Speed Axial Fan by Visualization of Sound Signals (2010)

This study describes the development of a novel stall-detection methodology for low-speed axial-flow fans. Because aerodynamic stall is a major potential cause of mechanical failure in axial fans, effective stall-detection techniques have had wide application for many years. However, aerodynamic stall does not always result in mechanical failure. A subsonic fan can sometimes operate at low speeds in an aerodynamically stalled condition without incurring mechanical failure. To differentiate between aerodynamic stall conditions that constitute a mechanical risk and those that do not, the stall-detection methodology in the present study utilizes a symmetrized dot pattern (SDP) technique that is capable of differentiating between stall conditions. This paper describes a stall-detections criterion based on a SDP visual waveform analysis and develops a stall-warning methodology based on that analysis. This study presents an analysis of measured acoustic and structural data across nine aerodynamic operating conditions represented in a 3×3 matrix. The matrix is a combination of (i) three speeds (full-, half-, and quarter-speed) and (ii) three operational states (stable operation, incipient stall, and rotating stall). The matrix of SDPs and structural data are used to differentiate critical stall conditions (those that will lead to mechanical failure of the fan) from noncritical ones (those that will not result in mechanical failure), thus providing a basis for an intelligent stall-warning methodology.
Highly Potent HIV-1 Protease Inhibitors with Novel Tricyclic P2 Ligands: Design, Synthesis, and Protein–Ligand X-ray Studies (2013)

The design, synthesis, and biological evaluation of a series of HIV-1 protease inhibitors incorporating stereochemically defined fused tricyclic P2 ligands are described. Various substituent effects were investigated to maximize the ligand-binding site interactions in the protease active site. Inhibitors 16a and 16f showed excellent enzyme inhibitory and antiviral activity, although the incorporation of sulfone functionality resulted in a decrease in potency. Both inhibitors 16a and 16f maintained activity against a panel of multidrug resistant HIV-1 variants. A high-resolution X-ray crystal structure of 16a-bound HIV-1 protease revealed important molecular insights into the ligand-binding site interactions, which may account for the inhibitor's potent antiviral activity and excellent resistance profiles.
Sirtuin 3 (SIRT3) Protein Regulates Long-chain Acyl-CoA Dehydrogenase by Deacetylating Conserved Lysines Near the Active Site (2013)

Long-chain acyl-CoA dehydrogenase (LCAD) is a key mitochondrial fatty acid oxidation enzyme. We previously demonstrated increased LCAD lysine acetylation in SIRT3 knockout mice concomitant with reduced LCAD activity and reduced fatty acid oxidation. To study the effects of acetylation on LCAD and determine sirtuin 3 (SIRT3) target sites, we chemically acetylated recombinant LCAD. Acetylation impeded substrate binding and reduced catalytic efficiency. Deacetylation with recombinant SIRT3 partially restored activity. Residues Lys-318 and Lys-322 were identified as SIRT3-targeted lysines. Arginine substitutions at Lys-318 and Lys-322 prevented the acetylation-induced activity loss. Lys-318 and Lys-322 flank residues Arg-317 and Phe-320, which are conserved among all acyl-CoA dehydrogenases and coordinate the enzyme-bound FAD cofactor in the active site. We propose that acetylation at Lys-318/Lys-322 causes a conformational change which reduces hydride transfer from substrate to FAD. Medium-chain acyl-CoA dehydrogenase and acyl-CoA dehydrogenase 9, two related enzymes with lysines at positions equivalent to Lys-318/Lys-322, were also efficiently deacetylated by SIRT3 following chemical acetylation. These results suggest that acetylation/deacetylation at Lys-318/Lys-322 is a mode of regulating fatty acid oxidation. The same mechanism may regulate other acyl-CoA dehydrogenases.
Digitally-Controlled UWB Pulse Generator for IEEE 802.1 5.4a systems (2007)

This paper provides the method of generating ultra wideband (UWB) pulses. The proposed UWB pulse generator is capable of all-digitally alternating the bandwidth, center frequency, and envelope of the pulse, which makes it easy to implement channelization for UWB network systems. In addition, our UWB pulse generator contributes to the transmitter's low power since it eliminates the need for a filter and phase locked loop (PLL), which is attractive for IEEE 802.15.4a UWB systems.
Polymer Pendant Ligand Chemistry. 3. A Biomimetic Approach to Selective Metal Ion Removal and Recovery from Aqueous Solution with Polymer-Supported Sulfonated Catechol and Linear Catechol Amide Ligands (1995)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPolymer Pendant Ligand Chemistry. 3. A Biomimetic Approach to Selective Metal Ion Removal and Recovery from Aqueous Solution with Polymer-Supported Sulfonated Catechol and Linear Catechol Amide LigandsSong-Ping Huang, Wei Li, Katherine J. Franz, Robert L. Albright, and Richard H. FishCite this: Inorg. Chem. 1995, 34, 11, 2813–2819Publication Date (Print):May 1, 1995Publication History Published online1 May 2002Published inissue 1 May 1995https://doi.org/10.1021/ic00115a006RIGHTS & PERMISSIONSArticle Views312Altmetric-Citations13LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (3 MB) Get e-Alerts Get e-Alerts
Iron Loss Deterioration by Shearing Process in Non-Oriented Electrical Steel with Different Thicknesses and Its Influence on Estimation of Motor Iron Loss (2013)

The influence of the shearing process on the iron loss of non-oriented electrical steels with thicknesses of 0.20-0.50mm was investigated. The deterioration of material iron loss was lesser in thinner steel sheets. The distribution of the increase in hardness near the sheared edge was almost half of the sheet thickness for all tested steels. Therefore, applying thinner steel sheets for the motor core may decrease the iron loss deterioration from the punching process. This argument was supported by measuring the iron loss of a model IPMSM using steels with different thicknesses and calculating the motor iron loss through FE analysis. The magnetic properties of narrow pieces corresponding to the width of the motor's teeth and yoke were shown to be important and useful to estimating the motor iron loss more accurately.
Polarization ratios anomalies of 3D rough surface scattering as second order effects (2002)

A detailed analysis of the behaviour of electromagnetic scattering from various corrugated bidimensional surfaces is presented. We show that rigorous electromagnetic computations on two dimensional surfaces can in fact yield HH/VV polarization ratios greater than one, with values consistent with those observed experimentally. We also show that HH/VV ratios greater than one are ubiquitous in the case of surfaces of the form f(x, y)=f/sub 1/(x)+f/sub 2/(y), known as crossed gratings in optics. Theoretically and numerically, these surfaces are shown to produce backscattered returns for which the first order Rice/Valenzuela term vanishes for off axis incidence. The second order term becomes dominant and has the property that HH returns exceed VV returns for a significant range of incident angles. Our approach is based on the methods of O.Bruno and F. Reitich (see J. Opt. Soc. A., vol.10, p.2551-62, 1993) which yield accurate results for a large range of values of the surface height. In particular, these methods can be used well beyond the domain of applicability of the first order theory of S.O. Rice (1951). The error in our calculations is guaranteed to be several orders of magnitude smaller than the computed values. The high order expansions provided by these methods are essential to determining the role played by the second order terms as they show that these terms indeed dominate most of the backscattering returns for the surfaces mentioned. Classically, large HH/VV ratios were sought by means of first order approximations on one dimensional sinusoidal profiles. In that case, we show that the first order terms do not vanish and the first order theories predict the behaviour of the backscattered returns, for small values of the height to period ratio. However, in the case of a two dimensional bisinusoidal surface, strong polarization dependent anomalies appear in the scattering returns as a result of the contributions of second order terms since, in that case, the first order contributions vanish.
Ka-Band Waveguide Two-Way Hybrid Combiner for MMIC Amplifiers (2010)

The design, simulation, and characterization of a novel Ka-band (32.05 0.25 GHz) rectangular waveguide two-way branch-line hybrid unequal power combiner (with port impedances matched to that of a standard WR-28 waveguide) has been created to combine input signals, which are in phase and with an amplitude ratio of two. The measured return loss and isolation of the branch-line hybrid are better than 22 and 27 dB, respectively. The measured combining efficiency is 92.9 percent at the center frequency of 32.05 GHz. This circuit is efficacious in combining the unequal output power from two Ka-band GaAs pseudomorphic high electron mobility transistor (pHEMT) monolithic microwave integrated circuit (MMIC) power amplifiers (PAs) with high efficiency. The component parts include the branch-line hybrid-based power combiner and the MMIC-based PAs. A two-way branch-line hybrid is a four-port device with all ports matched; power entering port 1 is divided in phase, and into the ratio 2:1 between ports 3 and 4. No power is coupled to port 2. MMICs are a type of integrated circuit fabricated on GaAs that operates at microwave frequencies, and performs the function of signal amplification. The power combiner is designed to operate over the frequency band of 31.8 to 32.3 GHz, which is NASA's deep space frequency band. The power combiner would have an output return loss better than 20 dB. Isolation between the output port and the isolated port is greater than 25 dB. Isolation between the two input ports is greater than 25 dB. The combining efficiency would be greater than 90 percent when the ratio of the two input power levels is two. The power combiner is machined from aluminum with E-plane split-block arrangement, and has excellent reliability. The flexibility of this design allows the combiner to be customized for combining the power from MMIC PAs with an arbitrary power output ratio. In addition, it allows combining a low-power GaAs MMIC with a high-power GaN MMIC. The arbitrary port impedance allows matching the output impedance of the MMIC PA directly to the waveguide impedance without transitioning first into a transmission line with characteristic impedance of 50 ohms. Thus, by eliminating the losses associated with a transition, the overall SSPA efficiency is enhanced. For reducing the cost and weight when required in very large quantities, such as in the beam-forming networks of phased-array antenna systems, the combiner can be manufactured using metal-plated plastic. Two hybrid unequal power combiners can be cascaded to realize a non-binary combiner (for e.g., a three-way) and can be synergistically optimized for low VSWR (voltage standing wave ratio), low insertion loss, high isolation, and wide bandwidth using commercial off-the-shelf electromagnetic software design tools.
Lateral ordering of quantum dots by periodic subsurface stressors (1999)

We investigate the possibility of using subsurface dislocation arrays as a tool for controlling the nucleation of self-assembled quantum dots (SAQDs). A quantitative model predicts that periodic nonuniform elastic fields on the surface induced by dislocations may control the lateral ordering SAQDs. The effect of dislocations is shown to be comparable to the interaction between buried and surface dots which leads to vertical dot stacking. The periodic subsurface dislocation arrays necessary for dot ordering can be produced by twist wafer bonding and backside substrate removal.
The development of a Compton lung densitometer (1989)

A field instrument is being developed for the noninvasive determination of absolute lung density using unique Compton backscattering techniques. A system consisting of a monoenergetic gamma-ray beam and a shielded high-resolution, high-purity-germanium (HPGe) detector in a close-coupled geometry is designed to minimize errors due to multiple scattering and uncontrollable attenuation in the chest wall. Results of studies on system performance with phantoms, the optimization of detectors, and the fabrication of a practical gamma-ray source are presented. It is concluded that the compact one-source one-detector system that has been developed has the potential of becoming a clinical instrument for measuring pulmonary edema.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
An exact interactive time visibility ordering algorithm for polyhedral cell complexes (1998)

A visibility ordering of a set of objects, from a given viewpoint, is a total order on the objects such that if object a obstructs object b, then b precedes a in the ordering. Such orderings are extremely useful for rendering volumetric data. The authors present an algorithm that generates a visibility ordering of the cells of an unstructured mesh, provided that the cells are convex polyhedra and nonintersecting, and that the visibility ordering graph does not contain cycles. The overall mesh may be nonconvex and it may have disconnected components. The technique employs the sweep paradigm to determine an ordering between pairs of exterior (mesh boundary) cells which can obstruct one another. It then builds on Williams' (1992) MPVO algorithm which exploits the ordering implied by adjacencies within the mesh. The partial ordering of the exterior cells found by sweeping is used to augment the DAG created in Phase II of the MPVO algorithm. The method thus removes the assumption of the MPVO algorithm that the mesh be convex and connected, and thereby allows one to extend the MPVO algorithm, without using the heuristics that were originally suggested by Williams (and are sometimes problematic). The resulting XMPVO algorithm has been analyzed, and a variation of it has been implemented for unstructured tetrahedral meshes; they provide experimental evidence that it performs very well in practice.
Drilling large diameter holes in rocks using multiple laser beams (2003)

Studies on drilling petroleum reservoir rocks with lasers show that modern infrared lasers have the capability to spall (thermally fragment), melt and vaporize natural earth materials with the thermal spallation being the most efficient rock removal mechanism. Although laser irradiance as low as 1000 W/cm2 is sufficient to spall rock, firing the beam on a single spot for too long at that intensity causes rock melting and reduces removal efficiency. Also, it is difficult to visualize an efficient way to create a six or eight inch hole by sending one large beam down hole. Alternatives are either to raster the beam to cover the 20 cm hole area or, using a pattern of many small beams illuminated sequentially or in groups, create a nearly circular work face. This paper will present the testing results of the multiple small beam method. The effect on rock removal efficiency of several parameters, including relaxation time between laser bursts, basic patterns of multiple beams, and beam spot overlapping amounts are determined and presented.
Real-Time Spoofing Detection Using Correlation Between two Civil GPS Receiver (2012)

A real.time method for detecting GPS spoofing in a narrow. bandwidth civilian GPS receiver has been implemented and tested, both in the absence of and in the presence of spoofing. The system was implemented as a software. defined radio system on a personal computer, using a pair of narrow.bandwidth radio front.ends that were geograp hically separated, with data transmitted between the two over the Internet. The presence of a spoofing signal is determined by mixing and accumulating the base.band quadrature channel samples from the two receivers, with the aim of cross.correlating the P(Y) code that should be present in both signals in the absence of spoofing. Several spoofing attacks were successfully detected in real. time.
Laser Bond Testing (2009)

The use of controlled, localized stress waves in materials and bonded joints offers new opportunities for the characterization of structures. Bonded joints in particular benefit from this application because there is no nondestructive testing method to measure bond strength. Laser bond testing using a high peak power, short-pulse laser can perform a localized proof test of a bond. The method can be applied nondestructively to strong bonds but will fail a weak bond, creating an internal disbond detectable by the laser bond testing system itself or by post-test ultrasonic testing. To date, numerous tests have shown the method to be sensitive to weak bonds in carbon fiber reinforced polymer composite structural bonds created by poor adhesive mixing, improper surface preparation or contamination.
Adaptive Closed-Loop Control Provides Blood-Glucose Regulation Using Dual Subcutaneous Insulin and Glucagon Infusion in Diabetic Swine (2007)

Using an automated adaptive glucose-control system, we show successful blood-glucose regulation in vivo and establish, definitively, the plausibility and practicality of closed-loop blood-glucose control using subcutaneous insulin and glucagon infusion in type 1 diabetes. The control system strikes an intricate balance between tight blood-glucose control and optimal drug consumption, while simultaneously maintaining emphasis on simplicity and reliability.