gebhart/patrepeval huggingface dataset:
Investigation of a pulsed electrothermal thruster system (1984)

The performance of an ablative wall Pulsed Electrothermal (PET) thruster is accurately characterized on a calibrated thrust stand, using polyethylene propellant. The thruster is tested for four configurations of capillary length and pulse length. The exhaust velocity is determined with twin time-of-flight photodiode stagnation probes, and the ablated mass is measured from the loss over ten shots. Based on the measured thrust impulse and the ablated mass, the specific impulse varies from 1000 to 1750 seconds. The thrust to power varies from .05 N/kW (quasi-steady mode) to .10 N/kW (unsteady mode). The thruster efficiency varies from .56 at 1000 seconds to .42 at 1750 seconds. A conceptual design is presented for a 40 kW PET propulsion system. The point design system performance is .62 system efficiency at 1000 seconds specific impulse. The system's reliability is enhanced by incorporating 20, 20 kW thruster modules which are fired in pairs. The thruster design is non-ablative, and uses water propellant, from a central storage tank, injected through the cathode.
Intra-Module DC-DC Converter: Topology Selection and Analysis (2013)

In this paper, firstly the effect of partial shading on output power of a photovoltaic system is discussed and the limitations of a centralized power conversion for extenuation that problem is described. Here, the aim is to discuss the limitations of the state-of-art power conversion system and to analyze the possible solutions. The benefits of the distributed power conversion in terms of overall photovoltaic system efficiency are explored. This work presents the requirements of the intra-module converter in photovoltaic system and also discusses the different factors that need to consider while implementing a DC-DC converter as an intra-module converter. A topology of high gain DC-DC converter is presented here, which can be used in photovoltaic applications as an intra-module converter. This paper also demonstrates the suitability of this presented converter in photovoltaic applications. Simulation results of the proposed converter are also presented here.
A novel channel estimation method: Blending correlation and least-squares based approaches (2002)

In this paper we introduce a novel channel estimation method which uses symbol rate sampled signals, based on blending the least squares based channel estimation and the correlation based channel estimation methods. We first overview the shortcomings of the least squares and the correlation based channel estimation algorithm, where a training sequence is utilized in both cases. The performance of the new channel estimation method will be demonstrated, such that the channel estimation will be more robust, and the overall quality of the estimate will be improved by recovering the pulse shape which is naturally embedded in the overall channel impulse response. We will demonstrate how both methods can be combined effectively to minimize the problems associated with the effective channel delay spread being longer than the known training sequence can support.
Robust acoustic echo cancellation in the short-time fourier transform domain using adaptive crossband filters (2014)

This paper presents a robust acoustic echo cancellation (AEC) system in the short-time Fourier transform (STFT) domain using adaptive crossband filters. The STFT-domain AEC allows for a simpler system structure compared to the traditional frequency-domain AEC, which normally requires several applications of the discrete Fourier transform (DFT) and the inverse DFT, while the robust AEC (RAEC) allows for continuous and stable filter updates during double talk without freezing the adaptive filter. The RAEC and the STFT-domain AEC have been investigated in the past in separate studies. In this work we propose a novel algorithm that combines the advantages of both approaches for robust update of the adaptive crossband filters even during double talk. Experimental results confirm the benefit of incorporating the robustness constraint for the adaptive crossband filters and show improved performance in terms of the echo reduction and the predicted sound quality.
Subject independent identification of breath sounds components using multiple classifiers (2014)

Breath sounds have been shown very valuable for diagnosis of obstructive sleep apnea. In this study, we present a subject independent method for automatic classification of breath and related sounds during sleep. An experienced operator manually labelled segments of breath sounds from 11 sleeping subjects as: inspiration, expiration, inspiratory snoring, expiratory snoring, wheezing, other noise, and non-audible. Ten features were extracted and fed into 3 different classifiers: näıve Bayes, Support Vector Machine, and Random Forest. Leave-one-out method was used in which data from each subject, in turn, is evaluated using models trained with all other subject. Mean accuracy for concurrent classification of all 7 classes reached 85.4%. Mean accuracy for separating data into 2 classes, snoring and non-snoring, reached 97.8%. To our knowledge, these are the highest accuracies achieved in automatic classification of all breath sounds components concurrently and for snoring, in a subject independent model.
The Streptococcus pneumoniae Pilus-1 Displays a Biphasic Expression Pattern (2011)

The Streptococcus pneumoniae pilus-1 is encoded by pilus islet 1 (PI-1), which has three clonal variants (clade I, II and III) and is present in about 30% of clinical pneumococcal isolates. In vitro and in vivo assays have demonstrated that pilus-1 is involved in attachment to epithelial cells and virulence, as well as protection in mouse models of infection. Several reports suggest that pilus-1 expression is tightly regulated and involves the interplay of numerous genetic regulators, including the PI-1 positive regulator RlrA. In this report we provide evidence that pilus expression, when analyzed at the single-cell level in PI-1 positive strains, is biphasic. In fact, the strains present two phenotypically different sub-populations of bacteria, one that expresses the pilus, while the other does not. The proportions of these two phenotypes are variable among the strains tested and are not influenced by genotype, serotype, growth conditions, colony morphology or by the presence of antibodies directed toward the pilus components. Two sub-populations, enriched in pilus expressing or not expressing bacteria were obtained by means of colony selection and immuno-detection methods for five strains. PI-1 sequencing in the two sub-populations revealed the absence of mutations, thus indicating that the biphasic expression observed is not due to a genetic modification within PI-1. Microarray expression profile and western blot analyses on whole bacterial lysates performed comparing the two enriched sub-populations, revealed that pilus expression is regulated at the transcriptional level (on/off regulation), and that there are no other genes, in addition to those encoded by PI-1, concurrently regulated across the strains tested. Finally, we provide evidence that the over-expression of the RrlA positive regulator is sufficient to induce pilus expression in pilus-1 negative bacteria. Overall, the data presented here suggest that the observed biphasic pilus expression phenotype could be an example of bistability in pneumococcus.
Dna Prime/Canarypox Boost—Based Immunotherapy of Chronic Hepatitis B Virus Infection in A Chimpanzee (2001)

There are about 200 million chronic hepatitis B virus (HBV) carriers at high risk of development of cirrhosis and hepatocellular carcinoma. Termination of the carrier state may avert these risks. We have investigated immunotherapy for chronic HBV infection in a chimpanzee HBV carrier using recombinant DNA-based immunization followed by a recombinant canarypox booster. One week after the booster, HBV DNA declined greater than 400-fold and remained undetectable by the quantitative polymerase chain reaction (PCR) assay for 186 weeks. Plasma levels of hepatitis B surface antigen (HBsAg) declined for only a short time. The decline in HBV DNA correlated with a boost in gamma interferon production without a corresponding boost in cytotoxic T lymphocyte levels, and decline in the transcriptional template or covalently closed circular DNA level. Confirmation of these findings requires further studies in chimpanzees and/or in humans.
In-Situ Resistance Coefficient Curve and Experimental Analysis of a Virtual Chilled Water Flow Meter at Air Handling Unit Level (2012)

In this paper, a virtual Air handling unit (AHU) level water flow meter using a control valve as a measurement device is experimentally validated through two different sizes of control valves on cooling coils. The flow through the valve is indirectly calculated using in-situ valve resistance coefficient curve, differential pressure over both the valve and its associated coil and valve stem positions. It was concluded in previous studies that the in-situ valve resistance coefficient curve is critical for determining the accuracy of the virtual valve flow meter. In this paper, an experimental approach and a theoretical approach of obtaining the in-situ valve resistance coefficient curve are introduced and as a result, accuracy of the virtual valve flow meters, using two different sizes of control valves: a smaller valve with design water flow rate of 25GPM and a larger valve with design water flow rate of 300GPM, is compared with an ultrasonic meter. The comparison show less than 4% of error over the full measurement range.
Monitoring Single‐Cell Infectivity from Virus‐Particle Nanoarrays Fabricated by Parallel Dip‐Pen Nanolithography (2007)

Sting like a bee: Nanoarrays of infectious virus particles, encoded with EGFP, are patterned by dip-pen nanolithography and exposed to a solution of cells. Upon infection, infected cells produce the EGFP protein, generating a green fluorescence signal that allows one to monitor the cellular infection process in real time (as seen in the optical image). These results suggest that antibody-immobilized virus particles retain their biological activity. Scale bar: 35μm. Supporting information for this article is available on the WWW under http://www.wiley-vch.de/contents/jc_2296/2007/z700244_s.html or from the author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.
Gradient-index design for mode conversion of diffracting beams (2016)

Gradient-index (GRIN) media offer advantages over thin optical elements for beam shaping of strongly diffracting fields. A numerical GRIN design method is presented, where diffraction effects are considered in solving for the refractive index profile. The index profile is found by specifying a desired beam transformation throughout the GRIN volume and solving a series of phase retrieval problems. A Gaussian to flat-top beam shaper and a coherent beam combiner are shown as examples. Reduced beam distortion is demonstrated in comparison to a purely geometric design method.
Overview on Solid Core Photonic BandGap Fibers (2009)

Abstract General properties of solid core photonic bandgap fibers are presented as well as general guidelines, found thanks to numerical investigations, helpful for designing this kind of fibers. We give two examples of applications and a new fiber design with interstitial air holes that lead to a significant reduction of both confinement and bend losses. This design allows the light to be guided in the fiber core thanks to a modified total internal reflection mechanism at long wavelengths and by photonic bandgap at short wavelengths. Furthermore, this new design satisfies the phase index matching condition for either second- or third-harmonic generation between two fundamental modes. Keywords: band diagramconfinement lossinterstitial air holes
Verifying the Consistency of Security Policies by Abstracting into Security Types (2007)

The service-oriented architecture (SOA) makes application development easier, because applications can be built from existing services with a bottom-up methodology. However, it is difficult to determine if a desired new service can be built from existing services. Not only the functional consistency of the existing services, but also the consistency of their non-functional (such as security) aspects must be verified. Message protection is an aspect of security. Every service needs an appropriate security policy defining the protection of messages exchanged between the parties to the service. Because of the intricacy of the Web services security policy language, it is difficult to verify the consistency of the security policies. We are developing a method to verify the consistency of security policies by abstracting them. Each security policy is abstracted, and then attached as a security type to the corresponding service in the application model. The security type denotes a security level for message protection. The security developer defines the possible abstraction methods. In this paper, we define the constraint of abstraction methods based on the semantics of the policy language. And also we state verifying the consistency of security types by using information flow analysis.
Determination of Time Resolved Heat Transfer Coefficient and Adiabatic Effectiveness Waveforms With Unsteady Film (2012)

Traditional hot gas path film cooling characterization involves the use of wind tunnel models to measure the spatial adiabatic effectiveness (η) and heat transfer coefficient (h) distributions. Periodic unsteadiness in the flow, however, causes fluctuations in both η and h. In this paper we present a novel inverse heat transfer methodology that may be used to approximate the η(t) and h(t) waveforms. The technique is a modification of the traditional transient heat transfer technique that, with steady flow conditions only, allows the determination of η and h from a single experiment by measuring the surface temperature history as the material changes temperature after sudden immersion in the flow. However, unlike the traditional transient technique, this new algorithm contains no assumption of steadiness in the formulation of the governing differential equations for heat transfer into a semi-infinite slab. The technique was tested by devising arbitrary waveforms for η and h at a point on a film cooled surface and running a computational simulation of an actual experimental model experiencing those flow conditions. The surface temperature history was corrupted with random noise to simulate actual surface temperature measurements and then fed into an algorithm developed here that successfully and consistently approximated the η(t) and h(t) waveforms.
Artificial insemination outcomes in beef females using bovine sperm with a detectable fertility-associated antigen. (2000)

In this study, semen samples from 25 bulls that had passed a breeding soundness evaluation were analyzed for the presence or absence of a 31-kDa protein, known as fertility-associated antigen (FAA), on spermatozoal membranes. Eighteen bulls had FAA on sperm (FAA-positive) and seven were devoid of FAA on sperm (FAA-negative). A single ejaculate from each bull was extended and frozen with 25 to 30 x 10(6) sperm in .5-mL straws. Crossbred replacement heifers (n = 865) were estrus-synchronized and artificially inseminated either at timed AI or 12 h after they were detected in estrus. Mature cows (n = 285) were inseminated 12 h after they were detected in estrus during a 45-d AI period. Pregnancy rates (pooled) to first AI service for females (n = 764) inseminated with FAA-positive sperm were 65.6% and were 49.7% for females (n = 386) inseminated with FAA-negative sperm (P < .005). Among the estrus-synchronized replacement heifers, pregnancy rates to synchronized AI service for heifers (n = 550) inseminated with FAA-positive sperm were 62% and were 45.7% for heifers (n = 315) inseminated with FAA-negative sperm (P < .005). These data indicate that pregnancy rates to first AI service at spontaneous and synchronized estrus are higher when using semen from bulls with detectable FAA on spermatozoal membranes compared to semen from bulls devoid of FAA on membranes. Fertility-associated antigen is an important determinant for fertility potential of sperm from bulls to be used in AI breeding programs.
Electrochemical system using conductive plastic. [plate substrate] (1978)

In a conductor--electrolyte--active material electrochemical environment, the conductor is protected against corrosion because that portion of the conductor in contact with the electrolyte and active material is formed of plastic filled with vitreous carbon. Adequate conductivity is obtained by finely dividing the vitreous carbon and loading the plastic with 40% to 80% carbon by volume. The filled plastic is particularly effective as a bipolar plate substrate. A layer of lead--antimony foil bonded to the carbon-filled plastic provides a good surface for adhering active materials. A lead sheet can be bonded to the substrate to define a low-resistance terminal. Forming the edges of the substrate of thicker sections of unfilled--hence, nonconductive--plastic allows the plates to be stacked to define a battery.
Distributed time reversal mirror array (2010)

An array of independent, separate, distributed time-reversal mirrors (TRMs) that can function as a large array in a coherent (collective and co-operative) manner is described. Due to the unique feature of time-reversal to compensate for the propagation delay after round-trip, the DTRMA can perform coherent integration of signals across the array through distorting media without the need for complicated array calibration and precise geo-location procedures, even after the location of a TRM has been changed. Several proof-of-concept experimental results to show both temporal and spatial focusing properties of the DTRMA are demonstrated using commercially available off-the-shelf components and instruments.
Optical to electrical energy conversion: cadmium telluride-based photoelectrochemical cells employing telluride/ditelluride electrolytes (1976)

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTOptical to electrical energy conversion: cadmium telluride-based photoelectrochemical cells employing telluride/ditelluride electrolytesArthur B. Ellis, Steven W. Kaiser, and Mark S. WrightonCite this: J. Am. Chem. Soc. 1976, 98, 20, 6418–6420Publication Date (Print):September 1, 1976Publication History Published online1 May 2002Published inissue 1 September 1976https://pubs.acs.org/doi/10.1021/ja00436a075https://doi.org/10.1021/ja00436a075research-articleACS PublicationsRequest reuse permissionsArticle Views206Altmetric-Citations54LEARN 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
An Optimized Method To Remove Filter Cake Formed by Formate-Based Drill-In Fluid in Extended-Reach Wells (2009)

Summary Smart, horizontal, and multilateral wells provide an attractive option for maximizing reservoir contact in both oil and gas fields in Saudi Arabia. Formate drill-in fluid has been selected lately for drilling gas wells because of its ability to preserve conventional polymers at high temperatures. The formate salts also can reduce the rate of hydrolytic and oxidative degradation of many viscosifiers and fluid loss agents at high temperatures. Drilling fluid filter cake can reduce the flow efficiency of cased or openhole wells. Calcium carbonate particles are frequently used as weighting material to maintain the pressure that is required for well control and minimize the leakoff. Such solids become consolidated and trapped in the polymeric material and this makes the filter cake a strong permeability barrier. The conventional method for cleaning the filter cake is by circulating solids-free formate brines at a high flow rate. This mechanical technique removes only the external drilling fluid damage. Chemical fluids like acids, oxidizers, or chelating agents are usually used as an alternative method for dissolving both the external and internal filter cake. Most of these fluids cannot give a full coverage to the wellbore because of the formation heterogeneity. A new class of esters can generate an acid downhole at a low rate and distribute it uniformly through the wellbore. Fluid compatibility and thermal stability tests were studied in detail. Return permeability experiments were conducted by using high-pressure/ high-temperature (HPHT) dynamic fluid loss cells. The ester solution was effective in cleaning the filter cake in comparison to the formate brines completion fluid and other organic acids results. Also, circulating formate brine to restore the wellbore permeability or remove the internal filter-cake damage was found to be insufficient. Surface tension measurements indicated that the generated alcohol and lactic acid from the ester solution had lowered the surface tension more than the formate brines.
Situation aware computing for big data (2014)

Big Data applications need a situation aware computing model to manage data, knowledge, and processes in an ever increasing amount, complexity, and speed while reacting as efficiently and timely as possible to any evolving situation. We introduce a Knowledge Intensive Data-processing System (KIDS) that empowers Big Data applications to support situation awareness. Frameworks such as Apache Hadoop YARN can be leveraged for repeated and near real-time execution of knowledge intensive applications. KIDS bridges the gap between the world of low-value data and the world of high-value information and knowledge, which are best handled by state of the art databases. These databases provide a host of much needed functions such as multi-temporality, flashback, provenance, and registered queries. With KIDS model, Big Data applications are well structured and can evolve perpetually.
Method for rapidly determining and reconstructing the peak arterial frame from a time-resolved CE-MRA exam (2000)

A method that determines the information necessary to reconstruct a single vascular image from a time-resolved CE-MRA exam is presented. Raw k-space data are used to approximate the time course of the contrast passage prior to image reconstruction. The resulting k-space contrast curve is used to select the data corresponding to peak arterial enhancement. These data are reconstructed and immediately presented for physician review, with the entire time-series of images available at a later time for more detailed diagnosis. This approach dramatically reduces the latency between acquisition of large 4D (3D plus time) data sets and presentation of a diagnostic quality time frame. This algorithm has proven successful in the imaging of several anatomical regions and-in exams that do not require a breath hold-permits the use of an acquisition method that produces a contrast-enhanced angiogram without a timing scan.