gebhart/patrepeval huggingface dataset:
Aerodynamic Design and Validation of a Contraction Profile for Flow Field Improvement and Uncertainty Quantification in a Subsonic Wind Tunnel (2020)

Model validation experiments are necessary for evaluating the accuracy of CFD simulations. Additionally, these experiments identify test-specific boundary conditions in a facility that are necessary for simulations to represent real flow-field environments. The quality of flow in a wind tunnel's contraction section propagates to the quality and uniformity of flow into the test section. Thus, knowledge of flow in this region is vital for providing accurate inflow conditions in a CFD simulation. This paper discusses a new contraction structure in the Virginia Tech Stability Wind Tunnel (VT SWT) that is overlaid on the previous contraction walls. This enhancement is motivated by an effort to develop the VT SWT as a landmark facility for CFD model validation studies. This design change makes the spanwise and transverse flow parameters to the test section comparable, equivalent, and quantifiable. Additionally, with its modular panel design, the liner extends the upstream reach of pressure sensing and allows a capability for customized instrumentation to accurately and continuously measure inflow behaviors into the test section. The order of magnitude of the mean average deviation in the average coefficients of pressures between all four walls is comparable to the order of instrumentation uncertainty. Thus, the contraction liner modification has mitigated uncertainty due to geometric irregularities in the inflow conditions. A smooth wall bump was tested on all four walls to separate the facility bias from the the three dimensional boundary layer flow over the bump. Deviations of average surface pressure between the four walls indicate that uncertainties in the model alignment and pressure tap quality contribute to significant bias in the sensitivities.
Fracture toughness of friction stir welded Invar 36 alloy at low temperature (2011)

The fracture toughness of friction stir welded Invar36 alloy,obtained with travelling speed of 2 mm/s and rotational speed from 200 r/min to 1 000 r/min,were estimated at low temperature(77 K)by small punch test,and were compared with that at room temperature(298 K)as well.At 298 K,all welds have higher small punch energy than the base material.For the welds acquired with the same welding parameters,the small punch energy tested at 77 K is always higher than the ones at 298 K.The small punch energy of welds trends to increase with decreasing of the rotational speed at both 77 K and 298 K. With rotational speeds equal or less than 400 r/min,the small punch energy of welds is significantly higher than that of the base material at 77 K.The results indicate that the friction stir welds keep excellent ductility at low temperature.With the increase of travelling speed,higher heat input produces a coarser microstructure and leads to the reduction of fracture toughness in the weld.
Method for Quantitative Evaluation of Kinetic Constants in Olefin Polymerizations, 3 (2007)

Abstract A method for the quantitative evaluation of kinetic constants in Ziegler–Natta and metallocene olefin homopolymerizations presented previously (V. Matos, A. G. M. Neto, J. C. Pinto, J. Appl. Polym. Sci. 2001 , 79 , 2076; V. Matos, A. G. M. Neto, M. Nele, J. C. Pinto, J. Appl. Polym. Sci. 2002 , 86 , 3226) is extended to allow for estimation of model parameters in copolymerization reactions. The method is used to estimate kinetic parameters of ethylene/propylene copolymerization during the synthesis of high impact poly(propylene) in a train of cascade reactors. Process models were developed to describe the reaction rate profile, reactor solubles, molecular weight distribution of the total polymer, xylene solubles, and insoluble polymer. The process models and the estimated parameters were inserted into a process simulator that successfully described the industrial process. magnified image
Approximate least squares parameter estimation with structured observations (2014)

The solution of inverse problems where the parameter being estimated has a known structure has been widely studied. In this work, we consider the situation where it is not appropriate to assume a structure for the parameter, but the observations on which the estimate are based are structured; specifically, when the observations are parametrized by a decomposable graphical model. This translates to structured sparsity of the inverse covariance matrix for Gaussian distributed observation vectors. We present an approximate least squares method which takes advantage of the structure to reduce the complexity of least squares. The approximate least squares method can be implemented recursively for even lower complexity. It is shown that the proposed method is asymptotically equivalent to least squares parameter estimation for a large number of observations. The properties of the algorithm are verified by simulation.
<title>Ion etching of ultranarrow structures</title> (1990)

We describe the use of Polymethylmethacrylate as both electron beam sensitive resist and ion etch mask for high-resolution pattern transfer. By using high-resolution electron beam lithography, chemically assisted ion beam etching, and in-situ metallization, we have fabricated ultra-narrow gates with lateral dimensions below 20 nm, spaced with < 50 nm pitch on high mobility 2D electron gas material. This technique, which is thought to provide extremely small lateral electron depletion lengths and well defined confienement potentials, allows us to produce new and more complicated structures for the study of quantum transport.
Yule-Nielsen approach for predicting the spectral transmittance of halftone prints (2009)

The transmittance spectrum of halftone prints on paper is predicted thanks to a model inspired by the Yule-Nielsen modified spectral Neugebauer model used for reflectance predictions. This model is well adapted for semi-opaque printing supports and applicable to duplex prints. Model parameters are obtained by a few transmittance measurements on calibration patches printed at one side of the paper. The model was verified with duplex specimens printed by inkjet with standard and custom inks, at different halftone frequencies and on various types of paper. Predictions are as accurate as those obtained with a previously developed reflectance and transmittance prediction model relying on the multiple reflections of light between the paper and the printair interfaces.
Standardized Iron Ore Characterization Methodology for Metallurgy (2015)

Abstract A comprehensive and reproducible evaluation of iron ores requires structured analytical methods. Therefore, a methodology has been developed which serves to evaluate the chemical and morphological characteristics. Seven different iron ores were examined with regard to their specific properties. For the standardized methodology, the following analytical methods have been applied: sieve analysis, chemical analysis, porosity measurement, reflected light and transmitted light microscopy. The developed method is suitable for a general mineralogical/petrographic characterization of all common raw or reduced iron ores and may also be applied with other ores.
Novel Electron-Phonon Relaxation Pathway in Graphite Revealed by Time-Resolved Raman Scattering and Angle-Resolved Photoemission Spectroscopy (2016)

Time dynamics of photoexcited electron-hole pairs is important for a number of technologies, in particular solar cells. We combined ultrafast pump-probe Raman scattering and photoemission to directly follow electron-hole excitations as well as the G-phonon in graphite after an excitation by an intense laser pulse. This phonon is known to couple relatively strongly to electrons. Cross-correlating effective electronic and phonon temperatures places new constraints on model-based fits. The accepted two-temperature model predicts that G-phonon population should start to increase as soon as excited electron-hole pairs are created and that the rate of increase should not depend strongly on the pump fluence. Instead we found that the increase of the G-phonon population occurs with a delay of $\sim$65 fs. This time-delay is also evidenced by the absence of the so-called self-pumping for G phonons. It decreases with increased pump fluence. We show that these observations imply a new relaxation pathway: Instead of hot carriers transferring energy to G-phonons directly, the energy is first transferred to optical phonons near the zone boundary K-points, which then decay into G-phonons via phonon-phonon scattering. Our work demonstrates that phonon-phonon interactions must be included in any calculations of hot carrier relaxation in optical absorbers even when only short timescales are considered.
Physical modeling of anisotropic domains: Ultrasonic imaging of laser-etched fractures in glass (2012)

ABSTRACT Many regions of subsurface interest are, or will be, fractured. Seismically characterizing these zones is a complicated but essential task for resource development. Physical modeling, using ultrasonic sources and receivers over scaled exploration targets, can play a useful role as an analog for reservoir imaging and assessment. We explored the anisotropic response of glass blocks containing internal fractures created by a novel laser-etching technique. We compared transmitted and reflected signals for P- and S-waves from fractured and unfractured zones in a suite of ultrasonic (1–5 MHz) experiments. The unaltered glass velocities have averages of 5804 and 3447 m/s for P- and S-waves, respectively (giving VP/VS=1.68). The unfractured glass has a very high quality (Q) factor of over 500 for P-waves and S-waves. The fractured zones have a small (up to 1.5%) velocity decrease. Signals propagating through the fractured zone have diminished amplitudes and increased coda signatures. Reflection surveys (zero-offset and with variable polarizations) record significant scatter from the fractured zones. The fracture-scattered energy can be migrated to provide a sharper image. The glass specimens with laser-etched fractures display a rich anisotropic response, which can help inform field-scale imaging.
P2‐278: A convergence between items on the Montreal Cognitive Assessment and neuropsychological tests in mild cognitive impairment: A factor analysis (2012)

The Montreal Cognitive Assessment (MoCA) is a brief test designed for the screening of mild cognitive impairment (MCI). The purpose of the test is to identify individuals who would be classified as having MCI following a comprehensive neuropsychological evaluation. The MoCA assesses multiple cognitive domains by one or more short items. These include visual-spatial/executive functioning assessed by trail-making, cube-drawing, and clock-drawing; naming assessed by a confrontational 3-item naming; memory assessed by a 5-item delayed recall; attention assessed by digit span, serial 7s, and letter-tapping; language assessed by sentence repetition and verbal fluency; abstraction assessed by a similarities task, and orientation to time and place. Previous studies have shown that MoCA is a valid and reliable tool for detecting MCI (e.g., Nasreddine et al., 2005). The current study intends to further validate the test through examination of how performance on individual items relates to the results from similar cognitive domains measured by established neuropsychological tests. The MoCA items were validated against performance on: subtests from the Wechsler Memory Scale Third Edition (WMS-III) and the Wechsler Adult Intelligence Scale Third Edition (WAIS-III), California Verbal Learning Test Second Edition (CVLT-II), Rey Auditory Verbal Learning Test (RAVLT), Boston Naming Test, Clock Drawing Test, Trail-Making Test, Stoop Task, Controlled Oral Word Association Test, and Semantic Probe Test. We conducted a factor analysis on sample of 320 MCI patients from the Memory Clinic at the Jewish General Hospital (Montréal). The results showed that individual items on the MoCA clustered together with neuropsychological tests that assess the same or similar cognitive function. For example, the delayed recall item on the MoCA clustered with delayed recall of short stories (WMS-III Logical Memory II), simple designs (WMS-III Visual Reproduction II), and a list of words (RAVLT or CVLT-II). Other MoCA items also clustered with neuropsychological tests in a meaningful fashion. Overall, these results support the validity of the MoCA items as the performance on these items correlated with performance on more comprehensive neuropsychological tests assessing similar cognitive ability. Thus, the MoCA contains useful screening items that are able to capture the specific cognitive difficulties that individuals with MCI experience.
PER-prediction for PHY mode selection in OFDM communication systems (2004)

Modern wireless communication standards like HiperLAN/2 or IEEE802.11a provide a high degree of flexibility on the physical layer (PHY) allowing the data link control (DLC) layer to choose transmission parameters with respect to the currently observed link quality. This possibility of so-called link adaptation (LA) is a key element for meeting quality of service (QoS) requirements and optimizing system performance. The decisions made by the LA algorithm are typically based on a prediction of the packet error rate (PER) implied by a certain transmit parameter setting. With most existing LA schemes, this prediction is based on the observed signal-to-noise ratio (SNR) or carrier-to-interference ratio (CIR), respectively. For frequency selective channels, however, the SNR alone does not adequately describe the channel quality. It is shown in this paper that LA schemes based on an accurate description of the momentary channel status can outperform conventional schemes with respect to throughput and reliability. Based on a novel "indicator" concept, schemes for obtaining an accurate prediction of the PER by evaluation of the channel transfer function are presented and evaluated by software simulation.
Solar Production of Hydrogen Using “Self-Assembled’’ Polyoxometalate Photocatalysts (2005)

Near-term and cost-effective production of solar hydrogen from inexpensive and readily available hydrogen containing compounds (HCCs) can boost the prospects of future hydrogen economy. In this paper, we assess the prospects of solar-assisted conversion of HCCs into hydrogen using polyoxometalate (POM) based photocatalysts, such as isopolytunstates (IPT) and silicotungstic acid (STA). Upon exposure to solar photons, IPT aqueous solutions containing various HCCs (e.g. alcohols, alkanes, organic acids, sugars, etc.) produce hydrogen gas and corresponding oxygenated compounds. The presence of small amounts of colloidal platinum increases the rate of hydrogen evolution by one order of magnitude. A solar photocatalytic flat-bed reactor, approximately 1.2 m × 1.2 m in size, was fabricated and tested for production of hydrogen from water-alcohol solutions containing IPT and STA and small amounts of colloidal Pt. The solar photoreactor tests demonstrated steady-state production of hydrogen gas for several days. IPT immobilized on granules of anion exchange resins with quaternary ammonium active groups show good photocatalytic activity for hydrogen production from water-alcohol solutions exposed to near-UV or solar radiation.
Cost-effective, Asynchronous 4 × 40Gbps Full-duplex OCDMA Demonstrator Using Apodized SSFBGs and a Multi-port Encoder/Decoder (2013)

Cost-effective, asynchronous 4 × 40Gbps full-duplex DPSK-OCDMA PON using 8-level phase-shifted, 320 Gchip/s apodized SSFBG en/decoders at each ONU and a single multi-port en/decoder at OLT is experimentally demonstrated for the first time.
Far-Field Signal Reduction (FSR) Leads Minimize Atrial Oversensing and Inappropriate Mode Switches (2005)

&lt;sec&gt;&lt;st&gt;Objectives&lt;/st&gt; A Far-Field Signal Reduction (FSR) lead, essentially based on tip-to-ring electrode spacing and surface area optimization, has been demonstrated to be effective in reducing far field signal in the right atrium. This study used a custom 24 hour real time holter monitor to evaluate sensing characteristics of FSR leads versus regular pacing leads (SJM Tendril 1688T). &lt;/sec&gt; &lt;sec&gt;&lt;st&gt;Methods&lt;/st&gt; 60 patients were randomized to either a FSR lead or a regular lead, placed at the RAA. At 10-day and 90-day follow up visits, each patient was put on a holter monitor for 24 hours real time IEGM recording. Detailed analysis of the recorded IGEM was conducted and any oversensing incidences were counted. Automatic mode switches due to atrial oversensing were counted between the two groups. &lt;/sec&gt; &lt;sec&gt;&lt;st&gt;Results&lt;/st&gt; The real time holter monitoring indicated that no atrial oversensing incidences occurred to the FSR patients versus about 20% of the control group. The number of inappropriate mode switches caused by oversensing in the control group was four times of that in the FSR patients. &lt;/sec&gt; &lt;sec&gt;&lt;st&gt;Conclusions&lt;/st&gt; Atrial far field ventricular oversensing events were dramatically reduced by the FSR leads. FSR leads demonstrated clinical benefits of significantly decreasing the number of oversensing caused inappropriate mode switches. &lt;/sec&gt;
Two-stage sintering inhibits abnormal grain growth during beta to alpha transformation in SiC (2008)

Free sintering of SiC with Al, B, and C additions in two successive stages, first under nitrogen and then under argon, produced a near full-density ceramic with equiaxed grain structure. The beta to alpha transformation proceeded to completion; however, the grain shape remained equiaxed due to the action of nitrogen present during the first stage of sintering. It is found that the beta to alpha transformation is necessary but not sufficient for producing the microstructure of interlocking plates found in high-toughness SiC.
Sildenafil Promotes Ischemia-Induced Angiogenesis Through a PKG-Dependent Pathway (2007)

These data demonstrate that sildenafil therapy results in increased angiogenic activity through a PKG-dependent pathway that is independent of nitric oxide production or NOS activity and identify the angiogenic therapeutic potential of sildenafil for critical limb ischemia.
Revisiting the visit: (2002)

This paper reports findings from a study of how a guidebook was used by pairs of visitors touring a historic house. We describe how the guidebook was incorporated into their visit in four ways: shared listening, independent use, following one another, and checking in on each other. We discuss how individual and groupware features were adopted in support of different visiting experiences, and illustrate how that adoption was influenced by social relationships, the nature of the current visit, and any museum visiting strategies that the couples had. Finally, we describe how the guidebook facilitated awareness between couples, and how awareness of non-guidebook users (strangers) influenced use.
Monocyte Apoptosis in Uremia Is Normalized with Continuous Blood Purification Modalities (2004)

Uremia is associated with a state of immune dysfunction. Dysregulation of homeostasis may be directly related to abnormal apoptosis regulation in uremia, which is crucial for the maintenance of the biological system. We demonstrated that plasma from three groups of uremic subjects, i.e. hemodialysis (HD) patients, peritoneal dialysis (PD) patients and patients with predialysis chronic renal failure (CRF), has different apoptotic potential on U937 monocytes. The plasma of HD and CRF subjects when incubated with U937 cells induced higher levels of apoptosis compared with that of PD and control subjects (HD 26.08 +/- 11.39, CRF 24.87 +/- 9.07, PD 12.13 +/- 4.51, controls 11.69 +/- 4.02). Furthermore, the phagocytic ability of U937 cells incubated with the various plasma demonstrated an impaired response in the HD and CRF subjects (HD 27.56 +/- 6.67, CRF 30.24 +/- 9.08, PD 36.55 +/- 9.80, controls 40.04 +/- 6.98). These results suggest that continuous blood purification, such as in PD, may have advantages over intermittent therapies in removing uremic apoptotic molecules and potentially maintaining biological function and homeostasis.
Demo Abstract: CDMA-based IoT Services with Shared Band Operation of LTE in 5G (2017)

With the vision of deployment of massive Internet-of-Things (IoTs) in 5G network, existing 4G network and protocols are inefficient to handle sporadic IoT traffic with requirements of low-latency, low control overhead and low power. To suffice these requirements, we propose a design of a PHY/MAC layer using Software Defined Radios (SDRs) that is backward compatible with existing OFDM based LTE protocols and supports CDMA based transmissions for low power IoT devices as well. This demo shows our implemented system based on that design and the viability of the proposal under different network scenarios.
Platelet Endothelial Cell Adhesion Molecule Deficiency or Blockade Significantly Reduces Leukocyte Emigration in a Majority of Mouse Strains (2004)

PECAM is a molecule used specifically during the diapedesis step when neutrophils and monocytes leave the blood compartment. Anti-PECAM reagents, such as Abs and soluble fusion proteins, block diapedesis both in vivo and in vitro. However, the PECAM knockout mouse in C57BL/6 strain has no serious defects in most models of inflammation. We show in this study that the same PECAM knockout backcrossed into the FVB/n strain clearly has reduced leukocyte emigration in two models of inflammation. Furthermore, we show that anti-PECAM reagents can block leukocyte emigration in several other wild-type strains of mice like FVB/n, SJL, and the outbred strain Swiss Webster. This clearly shows that the C57BL/6 strain is uniquely able to compensate for the loss of PECAM function. Murine models of inflammatory disease that have been studied using C57BL/6 mice should be re-evaluated using FVB/n or other mouse strains to determine whether PECAM plays a role in those models.
Fundamental performance limits in wideband relay architectures (2011)

The design of large-scale distributed wireless networks (e.g., mesh and ad-hoc networks, relay networks) poses a set of new challenges to information theory, communication theory, and network theory. Such networks are characterized by the large size of the network both in terms of the number of nodes (i.e., dense) and in terms of the geographical area the network covers. Each terminal can be severely constrained by its computational and transmission/receiving power. It is therefore important to understand how to utilize efficiently the physical infrastructure and system resources (power, bandwidth, etc.). Moreover, delay and complexity constraints along with diversity-limited channel behavior may require transmissions under insufficient levels of coding protection causing link outages. These constraints require an understanding of the performance limits of such networks and associated implications on network architectures jointly in terms of power and bandwidth efficiency and link reliability, especially when designing key operational elements essential in these systems, such as multihop routing and relay processing algorithms, bandwidth allocation policies, and relay deployment models.