gebhart/patrepeval huggingface dataset:
Explorations in image databases (1998)

This dissertation proposes Visual Computing and Perceptual search in databases as a new discipline, largely independent on the field of computer vision on which it rests.
Computer vision tries to build anthropomorphic systems that carry out some specific perceptual task in a largely independent manner. Perceptual databases, on the other hand, are systems, whose operation only makes sense in connection with a user that guides the system and validates the results. This dissertation shows that this difference has important repercussions on all aspects of the design of an image database, from the data representation to the interface design.
The second part of the dissertation proposes a mathematical model of image similarity suitable for application to social databases. The model is based on frames generated by discrete subgroup of a Lie group. The metric of Lie group is studied, as well as the metric of the color space in which images take values. This leads to the formulation of a theory in which image features are extremely general, and similarity criteria can be generated on the fly as a result of interaction with the user.
The generality of the similarity model could overwhelm the user, and needs to be harnessed by a suitable interface design. The third part of this dissertation proposes guidelines for interface design and the design of an interface for a general purpose image database. The interface is based on the idea that the user should explore the image space looking for interesting regions, rather than asking a query and expecting a meaningful response.
DNA Demethylase Is a Processive Enzyme (1999)

DNA methylation patterns are generated during development by a sequence of methylation and demethylation events. We have recently demonstrated that mammals bear a bona fide demethylase enzyme that removes methyl groups from methylated cytosines. A general genome wide demethylation occurs early in development and in differentiating cell lines. This manuscript tests the hypothesis that the demethylase enzyme is a processive enzyme. Using bisulfite mapping, this report demonstrates that demethylase is a processive enzyme and that the rate-limiting step in demethylation is the initiation of demethylation. Initiation of demethylation is determined by the properties of the sequence. Once initiated, demethylation progresses processively. We suggest that these data provide a molecular explanation for global hypomethylation.
Phosphorus-containing inhibitors of HMG-CoA reductase. I. 4-[(2-Arylethyl)hydroxyphosphinyl]-3-hydroxybutanoic acids: a new class of cell selective inhibitors of cholesterol biosynthesis (1990)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTPhosphorus-containing inhibitors of HMG-CoA reductase. I. 4-[(2-Arylethyl)hydroxyphosphinyl]-3-hydroxybutanoic acids: a new class of cell selective inhibitors of cholesterol biosynthesisDonald S. Karanewsky, Michael C. Badia, Carl P. Ciosek Jr., Jeffrey A. Robl, Michael J. Sofia, Ligaya M. Simpkins, Barbara DeLange, Thomas W. Harrity, Scott A. Biller, and Eric M. GordonCite this: J. Med. Chem. 1990, 33, 11, 2952–2956Publication Date (Print):November 1, 1990Publication History Published online1 May 2002Published inissue 1 November 1990https://pubs.acs.org/doi/10.1021/jm00173a007https://doi.org/10.1021/jm00173a007research-articleACS PublicationsRequest reuse permissionsArticle Views357Altmetric-Citations33LEARN 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 InRedditEmail Other access optionsGet e-Alertsclose Get e-Alerts
Highly selective etching of silicon nitride over silicon and silicon dioxide (1999)

A highly selective dry etching process for the removal of silicon nitride (Si3N4) layers from silicon and silicon dioxide (SiO2) is described and its mechanism examined. This new process employs a remote O2/N2 discharge with much smaller flows of CF4 or NF3 as a fluorine source as compared to conventional Si3N4 removal processes. Etch rates of Si3N4 of more than 30 nm/min were achieved for CF4 as a source of fluorine, while simultaneously the etch rate ratio of Si3N4 to polycrystalline silicon was as high as 40, and SiO2 was not etched at all. For NF3 as a fluorine source, Si3N4 etch rates of 50 nm/min were achieved, while the etch rate ratios to polycrystalline silicon and SiO2 were approximately 100 and 70, respectively. In situ ellipsometry shows the formation of an approximately 10-nm-thick reactive layer on top of the polycrystalline silicon. This oxidized reactive layer suppresses etching reactions of the reactive gas phase species with the silicon.
Integrated Protein-Crystal-Growing Apparatus (1991)

Proposed apparatus for research on growth of protein crystals dispenses drops of protein and precipitating solutions, provides controlled environment for crystalization, and stores crystals. Intended for use in microgravity of outer space, concept of apparatus also useful in design of self-contained terrestrial experiments for remote and/or automatic execution.
Designing a practical data filter cache to improve both energy efficiency and performance (2013)

Conventional Data Filter Cache (DFC) designs improve processor energy efficiency, but degrade performance. Furthermore, the single-cycle line transfer suggested in prior studies adversely affects Level-1 Data Cache (L1 DC) area and energy efficiency. We propose a practical DFC that is accessed early in the pipeline and transfers a line over multiple cycles. Our DFC design improves performance and eliminates a substantial fraction of L1 DC accesses for loads, L1 DC tag checks on stores, and data translation lookaside buffer accesses for both loads and stores. Our evaluation shows that the proposed DFC can reduce the data access energy by 42.5% and improve execution time by 4.2%.
Living anionic polymerization of (meth)acrylic esters: New mechanistic concepts and resulting materials (1998)

Abstract As an illustration of the frantic development of (meth)acrylic esters anionic polymerization during the last decade, three significant breakthroughs will be presented and analyzed:— extension of the LAP (ligated anionic polymerization) concept to the practical synthesis of both high iso‐ or syndio high MW PMMA; — the production of “perfect” hydrocarbon gels from tailored PMMA‐polybutadiene‐PMMA triblock copolymers; — the use of reactivity “boosters” allowing to climb back up the nucleophilic reactivity scale, i.e. initiating styrene, dienes and (meth)acrylates polymerization with alcoholates and silanolates.
Detecting super‐thin clouds with polarized sunlight (2014)

Abstract We report a novel method for detecting cloud particles in the atmosphere. Solar radiation backscattered from clouds is studied with both satellite data and a radiative transfer model. A distinct feature is found in the angle of linear polarization of solar radiation that is backscattered from clouds. The dominant backscattered electric field from the clear‐sky Earth‐atmosphere system is nearly parallel to the Earth surface. However, when clouds are present, this electric field can rotate significantly away from the parallel direction. Model results demonstrate that this polarization feature can be used to detect super‐thin cirrus clouds having an optical depth of only ~0.06 and super‐thin liquid water clouds having an optical depth of only ~0.01. Such clouds are too thin to be sensed using any current passive satellite instruments.
Kurtosis-based criteria for adaptive blind source separation (2002)

We consider the problem of separating adaptively p synchronous user signals that are received by an m-element antenna array without the use of training sequences. We establish a set of necessary and sufficient conditions for perfect recovery of all the transmitted signals. Based on these conditions we propose optimization criteria that lead to adaptive algorithms for efficient blind source separation of non-Gaussian signals. Convergence analysis shows important global convergence properties of the proposed techniques. Combined with their low complexity, these features make the proposed algorithms good candidates for adaptive source separation.
Smoothing curvature of trajectories constructed by noisy measurements in path planning problems for wheeled robots (2008)

A path planning problem for a wheeled robot is considered. The problem consists in constructing a trajectory that approximates a given ordered sequence of points on the plane and satisfies certain smoothness requirements and curvature constraints. Such a problem arises, for example, when it is required to follow in an automated mode a path stored as a discrete set of points measured in the course of the first passage of this path in a manual mode. Due to errors inherent in the data points, the shape of the curve approximating the desired path may turn out inappropriate or even unacceptable from the control standpoint. The shape of the curve can be improved by applying the so-called fairing, which consists in moving the original data points with the aim to minimize some functional. Adequate small variations of the data points (within the measurement error) preserve the proximity of the resulting path to the original data points and, at the same time, may considerably improve its shape. In the paper, a new global fairing method for improving shape of curves consisting of elementary B-splines is proposed. The improvement is achieved through minimization of jumps of the spline third derivative. The problem of finding desired variations reduces to solving a quadratic programming problem with simple constraints. The discussion is illustrated by numerical examples.
Matrix-assisted laser desorption ionization mass spectrometry-fundamentals and applications (1993)

Matrix‐assisted laser desorption ionization (MALDI) mass spectrometry has found considerable acceptance by the analytical community. Though the principal ideas are well‐established, i.e. the incorporation of analyte molecules into a solid matrix (usually solid), the resonant excitation of the matrix molecules by an intense short pulse of laser light (either UV or IR) inducing a phase transition of a microvolume and desorbing intact matrix and analyte molecules, and the charging of analytes by (photo)chemical ionization processes, understanding of the underlying elementary processes is still rudimentary and optimization of the experimental parameters is done empirically. The current status of the analytical applications will be described. Whereas molecular weight determination of proteins is routinely done in many laboratories today, the technique can also be applied to other classes of biomolecules, such as glycoconjugates, carbohydrates and nucleic acids, as well as to technical polymers. The current understanding of the desorption ionization process is discussed, emphasizing the authors investigations of the incorporation and ablation phenomena.
Tomographic reconstruction for tilted helical multislice CT (2000)

One of the most recent technical advancements in computed tomography (CT) is the introduction of multislice CT (MCT). Because multiple detector rows are used for data acquisition, MCT offers higher volume coverage, faster scan speed, and reduced X-ray tube loading. Recognizing its unique data-sampling pattern, several image reconstruction algorithms were developed. These algorithms have been shown to be adequate in producing clinically acceptable images. Recent studies, however, have revealed that the image quality of MCT can be significantly degraded when helical data are acquired with a tilted gantry. The degraded image quality has rendered this feature unacceptable for clinical usage. In this paper, we first present a detailed investigation on the cause of the image quality degradation. An analytical model is derived to provide a mathematical basis for correction. Several compensation schemes are subsequently presented, and a detailed performance comparison is provided in terms of spatial resolution, noise, computation efficiency, and image artifacts.
Multiple‐Etchant Loading Effect and Silicon Etching in ClF3 and Related Mixtures (1982)

Fluorine atoms are a highly selective etchant for silicon, while chlorine atoms etch silicon selectively and anisotropically in the presence of ion bombardment. Experimental results from silicon etching in plasmas show that gases and gas mixtures containing both etchants can be used to etch silicon selectively with a controlled degree of anisotropy. These multicomponent etchant mixtures exhibit a significant loading effect that is outside the scope of previous analyses. A general multiple‐etchant loading effect model is derived which agrees well with data from the system. It is shown that loading in a two‐etchant plasma is a function of three‐dimensionless parameters: and , the slopes of the single etchant loading effect curves, and , the ratio of etching by etchant 2 to that by etchant 1 when negligible etchable material is in the reactor.
All‐organic actuator fabricated with single wall carbon nanotube electrodes (2008)

Abstract Compliant electrodes to replace conventional metal electrodes have been required for many actuators to relieve the constraint on the electroactive layer. Many conducting polymers have been proposed for the alternative electrodes, but they still have a problem of poor thermal stability. This article reports a novel all‐ organic actuator with single wall carbon nanotube (SWCNT) films as an alternative electrode. The SWCNT film was obtained by filtering a SWCNT solution through an anodized alumina membrane. The conductivity of the SWCNT film was about 280 S/cm. The performance of the SWCNT film electrode was characterized by measuring the dielectric properties of NASA Langley Research Center – Electroactive Polymer (LaRC‐EAP) sandwiched by the SWCNT electrodes over a broad range of temperature (from 25 to 280 °C) and frequency (from 1 kHz to 1 MHz). The all‐organic actuator with the SWCNT electrodes showed a larger electric field‐induced strain than that with metal electrodes, under identical measurement conditions. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 2532–2538, 2008
Flow Resistivity Instrument (1983)

A method and apparatus for making in-situ measurements of flow resistivity on the Earth's ground surface is summarized. The novel feature of the invention is two concentric cylinders, inserted into the ground surface with a measured pressure applied to the surface inside the inner cylinder. The outer cylinder vents a plane beneath the surface to the atmosphere through an air space. The flow to the inner cylinder is measured thereby indicating the flow from the surface to the plane beneath the surface.
Allosteric modifiers of hemoglobin: 2-[4-[[(3,5-disubstituted anilino)carbonyl]methyl]phenoxy]-2-methylpropionic acid derivatives that lower the oxygen affinity of hemoglobin in red cell suspensions, in whole blood, and in vivo in rats (1992)

Two new potent allosteric effectors of hemoglobin, RSR-4 [2-[4-[[(3,5-dichloroanilino)carbonyl]-methyl]phenoxy]-2- methylpropionic acid] and RSR-13 [2-[4-[[(3,5-dimethlanilino)carbonyl]methyl]-phenoxy]-2-methylp rop ionic, are compared to the previously reported compounds L3,5 and L3,4,5 [Lalezari, I., Lalezari, P., Poyart, C., Marden, M., Kister, J., Bohn, B., Fermi, G., & Perutz, M. F. (1990) Biochemistry 29, 1515]. Unlike L3,5 and L3,4,5, RSR-4 and RSR-13 are less impeded by physiological concentrations of serum albumin. RSR-4 has also been shown to be more effective than L3,5 in shifting the allosteric equilibrium of bovine Hb toward the low-affinity T-state. X-ray crystal studies show that both RSR-4 and RSR-13 bind to only one pair of symmetry-related sites in the Hb central water cavity whereas previous studies on L3,5 and L3,4,5 demonstrated a second pair of symmetry-related binding sites near Arg 104 beta. Three major interactions between these allosteric effectors and Hb include the acid group with the guanidinium group of C-terminal Arg 141 alpha, the effector's amide oxygen with the ammonium ion of Lys 99 alpha, and the phi electrons of the halogenated or methylated aromatic ring and Asn 108 beta. No explanation has been found for the difference in number of binding sites observed for RSR-4 and RSR-13 (two sites) compared to L3,5 and L3,4,5 (four sites); also no correlation has been made between the number of binding sites and degree of allosteric shift in the oxygen equilibrium curve.(ABSTRACT TRUNCATED AT 250 WORDS)
Mild route to generate gaseous metal anions (2011)

Gaseous metal anions such as Na(-), K(-), Cs(-), and Ag(-) can be generated at ambient temperatures by the collision-induced dissociation of the anions of several dicarboxylic acid salts, including oxalate, maleate, fumarate, succinate, and glutamate salts. The formation of gaseous metal anions in this way is unprecedented because the metal is initially present in its cationic form. The mild process described here could facilitate novel applications of metal anions as selective reagents for gas-phase ion-molecule and ion-ion reactions. Ab initio calculations were used to describe the dissociation process for anions of the oxalate salts. The formation of alkalides occurs via production of a metal-carbon dioxide anion intermediate with a bidentate three-center two-electron bond to the metal. The metal atom acquires a partial negative charge in the intermediate structure.
Effect of Ligand Backbone on the Selectivity and Stability of Rhodium Hydroformylation Catalysts Derived from Phospholane-Phosphites (2021)

A study on how ligand backbone structure has an impact on selectivity, rate, and catalyst stability of hydroformylation catalysts was prompted by some longer-term stability issues being discovered for a phospholane-phosphite with a [−CH2O−] backbone. A series of phospholane-phosphite ligands were synthesized. Catalysts made in situ from these ligands and [Rh(acac)(CO)2] were found to give iso-butanal selectivities up to 75% at temperatures between 75 and 105 °C: the latter being a benchmark for iso-selectivity in reactions conducted at industrially meaningful temperatures. A racemic rhodium complex of a bidentate phospholane-phosphite from a tropos-biphenol with an extended backbone showed unusually high stability at high temperatures, combined with even better iso-selectivity in propene hydroformylation relative to the original complex. A related ligand with an electron-withdrawing group maintained the unusually high stability and improved activity. Characterization of the precatalysts of type [RhH(CO)2(L)] was accomplished using in situ HPIR spectroscopy and backed up by density functional theory calculations (B3PW91-D3 level) and by NMR studies; the latter showed that the variation of the backbone also had a pronounced impact on the precatalyst structure. A key finding is that it is now possible to prepare phospholane-phosphite ligands that deliver high iso-butanal selectivity and that show no signs of degradation after several days even above typical reaction temperatures. In one stability test, several kilograms of aldehydes were produced with TOF and selectivity being consistent over several days.
Fault-tolerant Control of a Wind Turbine with a Squirrel-cage Induction Generator and Rotor Bar Defects (2011)

Wind turbines are usually installed on remote locations and in order to increase their economic competence malfunctions should be reduced and prevented. Faults of wind turbine generator electromechanical parts are common and very expensive. This paper proposes a fault-tolerant control strategy for variable-speed variable-pitch wind turbines in case of identified and characterized squirrel-cage generator rotor bar defect. An upgrade of the torque control loop with flux-angle-based torque modulation is proposed. In order to avoid or to postpone generator cage defects, usage of pitch controller in the low wind speed region is introduced. Presented fault- tolerant control strategy is developed taking into account its modular implementation and installation in available control systems of existing wind turbines to extend their life cycle and energy production. Simulation results for the case of a 700 kW wind turbine and the identified rotor bar fault are presented.
VLSI digital polarity correlator based on an overloading counter technique (1983)

A VLSI structure to implement a digital polarity correlator using an overloading integrating counter technique is reported. The implementation permits direct cascading of individual correlator chips without using additional circuits, to give complete flexibility in choice of correlator delay and resolution. The design considered offers significant performance advantages in high-speed correlation applications.
Demonstration of a diode-laser-based high spectral resolution lidar (HSRL) for quantitative profiling of clouds and aerosols (2017)

We present a demonstration of a diode-laser-based high spectral resolution lidar. It is capable of performing calibrated retrievals of aerosol and cloud optical properties at a 150 m range resolution with less than 1 minute integration time over an approximate range of 12 km during day and night. This instrument operates at 780 nm, a wavelength that is well established for reliable semiconductor lasers and detectors, and was chosen because it corresponds to the D2 rubidium absorption line. A heated vapor reference cell of isotopic rubidium 87 is used as an effective and reliable aerosol signal blocking filter in the instrument. In principle, the diode-laser-based high spectral resolution lidar can be made cost competitive with elastic backscatter lidar systems, yet delivers a significant improvement in data quality through direct retrieval of quantitative optical properties of clouds and aerosols.