gebhart/patrepeval huggingface dataset:
Unlocking Tight Oil: Selective Multi-Stage Fracturing in the Bakken Shale (2008)

Abstract In recent years, the formation known as the Bakken Shale in eastern Montana and western North Dakota has seen enormous growth in oil and gas production. Scientists from the United States Geological Survey have commented that the area has the potential to become "the next Saudi Arabia." In most cases, the Bakken horizontal wells are fracture stimulated. However, with several thousand feet of formation, effective stimulation of the entire length has proven time-consuming and costly. In the past, a single-leg zone was fractured all at the same time, regardless of the varied permeability of the layers. Although this simple method of stimulation was seen as a success at the time, a new, more efficient method using swellable packers with reactive elements now promises to optimize total recovery and minimize fracturing cost. Case history data will show how employing multiple frac sleeves with swellable packers straddling each interval proves to be a cost-effective way to stimulate multiple zones and save days of rig time. Specific experience in the Bakken field provides an optimization model for worldwide well completion markets
OFDM Chirp Radar Target Detection and Adaptive Design In Clutter Environment (2018)

In this paper, orthogonal frequency division multiplexing chirp waveform is proposed for moving target detection in clutter environment. Unlike the OFDM waveform, the proposed waveform has better peak to average power ratio (PAPR) and offers larger time-bandwidth product which is suitable for target detection. In this scheme, the OFDM chirp waveform is employed to formulate a measurement model which considers multiple frequencies under the environment of doppler shift and noise. Based on this model, hypothesis test is developed using Generalized Likelihood Ratio Test (GLRT) by exploiting the advantages of OFDM chirp waveform. In addition, adaptive design algorithm is incorporated in the model for the next transmitting waveform. Furthermore, we present a possible implementation of an OFDM chirp waveform pulse with its ambiguity function. Performance analysis has also been done in terms of empirical cumulative distribution function (ECDF). The results demonstrate the superiority of the OFDM chirp radar over OFDM radar in target detection.
Permeability Determination From Well Log Data (1997)

Summary We discuss and compare three different approaches for permeability determination from logs from a practical point of view. The three methods, empirical, statistical, and the recently introduced "virtual measurement," make use of empirically determined models, multiple variable regression, and artificial neural networks, respectively. We apply all three methods to well log data from a heterogeneous formation and compare the results with core permeability, which is considered to be the standard. Our comparison focuses on the predictive power of each method.
Efficient and reliable methods for rounded-interval arithmetic (1998)

We present an efficient and reliable method for computing the unit-in-the-last-place (ulp) of a double-precision floating-point number, taking advantage of the standard binary representation for floatingpoint numbers defined by IEEE Std 754-1985. The ulp is necessary to perform software rounding for robust rounded-interval arithmetic (RIA) operations. Hardware rounding, using two of the standard rounding modes defined by IEEE-754, may be more efficient. RIA has been used to produce robust software systems for the solution of systems of nonlinear equations, interrogation of geometric and differential properties of curves and surfaces, curve and surface intersections, and solid modeling.
The proper statistical nature of measuring and estimating (2003)

In wireless communications, all received signals have a statistical nature. The statistical nature usually comes from a stationary environment. In order to ensure of sufficient signal strength coverage, many methods of estimating or predicting signal strength appear in the technical literature. However, the improper statistical process can sometimes mislead to untrue characteristics in the wireless communications signal. This paper studies the proper means of generating statistical data for assisting with system designs in three steps. First, it examines how to analyze the measured data by going through ergodic processes, i.e., ensuring the ensemble average equals the time average; second, it shows how to handle the measured data in a nonstationary environment; and third, it discusses how to generate a statistical database by using estimations such as ray-tracing techniques in propagation or Rayleigh-fading simulations in data transmission. The boundary of the statistical nature and the caution of using it is addressed as well.
Fatigue Life of Coiled Tubing With External Mechanical Damage (2007)

Abstract Coiled tubing (CT) is used in a rough and dynamic environment that renders it susceptible to mechanical damage on its outer surface. Such damage can adversely affect the fatigue life of CT by causing localized concentration of stresses and strains, or inducing microcracks from severe localized plastic deformation, that can lead to premature fatigue failure of the pipe. Failure statistics based on detailed failure examinations by BJ Services Company rank mechanical damage as the leading cause of CT failures accounting for 35% of all investigations. Repairs of the damaged pipe by welding or grinding are not always practical or even possible; therefore it is important to be able to estimate the remaining fatigue life of the damaged pipe so that the well servicing job can be completed with minimum risk of failure. Research efforts by the Coiled Tubing Mechanics Research Consortium at Tulsa University to determine the fatigue de-rating factors for damaged CT produced an algorithm ("Flexor TU4") that can predict the remaining fatigue life of the CT based on specific damage geometry, tubing characteristics and operating parameters. However, the majority of the testing for this algorithm has been conducted in air on artificial defects (i.e. machined) introduced on new and pre-fatigued tubing samples. Little previous research has been conducted to compare "Flexor TU4" predictions with the remaining fatigue life measured on CT with real defects (i.e. damage caused during service). Also, the effect of mechanical damage on the fatigue life of coiled tubing when exposed to sour environments (i.e. H2S) has not yet been reported in the literature. This paper describes the effect of different types of damage on the material and fatigue life of CT and presents a comparison between "Flexor TU4" predictions and the fatigue life measured for strings with external mechanical damage incurred during service. Also a comparison between the sour fatigue life and that in air is presented in terms of percentages of sweet life (i.e. non-sour) for coiled tubing fatigue samples containing artificially induced mechanical damage on the external surface prior to being exposed to sour environments.
Determining Transpiration from<i>Pinus patula</i>Shoots—A Comparative Evaluation of the Cut-Shoot Method and Two Null-Balance Diffusion Porometers (1990)

SYNOPSIS The cut-shoot method and two types of small-chambered null-balance diffusion porometer were evaluated for suitability in studies of stomatal conductance and transpiration in Pinus patula. In the course of the cut-shoot evaluation, excised shoots were found to transpire at a constant rate for up to four minutes following excision before the effects of the cut became apparent. An experiment involving seedlings in sealed pots showed the four-minute post-excision transpiration rate to be the same as before excision. The porometers were each used to measure leaf conductance of 10 fascicle groups on five shoots selected from different seven-year-old trees. Good correlation was found between transpiraton rates derived from the two porometers and the cut-shoot method. Variation in porometer resistance readings within and between shoots was high. It was concluded that the cut-shoot method is more suitable for use in studies of whole tree canopies where destructive sampling of shoots is possible. The use of small-chambered porometers in such cases is limited by the number of readings required to obtain a reliable estimate of transpiration. Their use is more appropriate in studies involving a limited number of fascicles or shoots, where adequate sampling can be achieved.
Shear bond strength of all-ceramic cement to dentin (2005)

Objective To determine the shear bond strength (SBS) of all-ceramic cement to dentin. The hypothesis was that adhesive bonding capacity is influenced by different surface pretreatments designed for dentin.Methods Fifteen extracted permanent molars were polished to expose a dentin surface and then randomly assigned to 3 groups. Group I specimens were treated with a 10% citric acid and 3% ferric chloride (10-3 solution), group II with a 0.5M EDTA, and group III with a 20% phosphoric acid (20% PA).All specimens were then cemented with all-ceramic cement to composite resin slices.After stored under 37℃ distilled water for 24h,the SBS were measured. Data were analyzed with one-way analysis of variance.Results The results were 20.61±3.56 MPa for group I, 11.54± 2.81 MPa for group II, and 26.84±3.37 MPa for group III specimens. Statistical analysis showed that the differences among all groups were significant (P0.05).Conclusion A successful bond can be achieved between all-ceramic cement and dentin after 20% PA conditioning.
Development of Porous Metal-supported Solid Oxide Fuel Cells (2013)

The introduction of metal supported cells may be a key innovation in the development of solid oxide fuel cell (SOFC) technology. The objective of this study was to develop a process of co-firing the ceramic layers of a solid oxide fuel cell attached to their porous metal support. This is a major departure from the traditional fuel cell architecture where the support layer is a ceramic composite made of YSZ and NiO. The problems to be eliminated during the fabrication process include the warping, cracking and delamination of the cell during the co-sintering process. In this study, the porous metal layer was produced by the freeze tape casting process. During co-sintering, it is necessary to match the relative shrinkage between the metal and ceramic layers. Different parameters which can influence the relative shrinkage were explored, including the heating rate, sintering temperature, sintering time, cell thickness, solid loading of the green tapes, applications of wet and dry hydrogen in the sintering atmosphere, as well as a change of the electrolyte material. Specifically, GDC was tested as an alternative electrolyte to YSZ. Since the porous metal substrate is exposed to air during fuel cell operation, it must be protected from oxidation. Therefore, the pack cementation method was used to apply a layer of aluminum onto the metal substrate. Variables such as temperature and exposure time of the coating materials were investigated in this thesis.
Functional dissection and module swapping of fungal cyclooligomer depsipeptide synthetases (2013)

BbBSLS and BbBEAS were dissected and reconstituted in Saccharomyces cerevisiae. The intermodular linker is essential for the reconstitution of the separate modules. Module 1 can be swapped between BbBEAS and BbBSLS, while modules 2 and 3 control the product profiles. BbBSLS is a flexible enzyme that also synthesizes beauvericins.
Receiver operating characteristic (ROC) curve for classification of18F-NaF uptake on PET/CT (2016)

Abstract Objective: To assess the cutoff values established by ROC curves to classify18F-NaF uptake as normal or malignant. Materials and Methods: PET/CT images were acquired 1 hour after administration of 185 MBq of18F-NaF. Volumes of interest (VOIs) were drawn on three regions of the skeleton as follows: proximal right humerus diaphysis (HD), proximal right femoral diaphysis (FD) and first vertebral body (VB1), in a total of 254 patients, totalling 762 VOIs. The uptake in the VOIs was classified as normal or malignant on the basis of the radiopharmaceutical distribution pattern and of the CT images. A total of 675 volumes were classified as normal and 52 were classified as malignant. Thirty-five VOIs classified as indeterminate or nonmalignant lesions were excluded from analysis. The standardized uptake value (SUV) measured on the VOIs were plotted on an ROC curve for each one of the three regions. The area under the ROC (AUC) as well as the best cutoff SUVs to classify the VOIs were calculated. The best cutoff values were established as the ones with higher result of the sum of sensitivity and specificity. Results: The AUCs were 0.933, 0.889 and 0.975 for UD, FD and VB1, respectively. The best SUV cutoffs were 9.0 (sensitivity: 73%; specificity: 99%), 8.4 (sensitivity: 79%; specificity: 94%) and 21.0 (sensitivity: 93%; specificity: 95%) for UD, FD and VB1, respectively. Conclusion: The best cutoff value varies according to bone region of analysis and it is not possible to establish one value for the whole body.
Fatal Bilateral Chylothorax in Mice Lacking the Integrin α9β1 (2000)

Members of the integrin family of adhesion receptors mediate both cell-cell and cell-matrix interactions and have been shown to play vital roles in embryonic development, wound healing, metastasis, and other biological processes. The integrin alpha9beta1 is a receptor for the extracellular matrix proteins osteopontin and tenacsin C and the cell surface immunoglobulin vascular cell adhesion molecule-1. This receptor is widely expressed in smooth muscle, hepatocytes, and some epithelia. To examine the in vivo function of alpha9beta1, we have generated mice lacking expression of the alpha9 subunit. Mice homozygous for a null mutation in the alpha9 subunit gene appear normal at birth but develop respiratory failure and die between 6 and 12 days of age. The respiratory failure is caused by an accumulation of large volumes of pleural fluid which is rich in triglyceride, cholesterol, and lymphocytes. alpha9(-/-) mice also develop edema and lymphocytic infiltration in the chest wall that appears to originate around lymphatics. alpha9 protein is transiently expressed in the developing thoracic duct at embryonic day 14, but expression is rapidly lost during later stages of development. Our results suggest that the alpha9 integrin is required for the normal development of the lymphatic system, including the thoracic duct, and that alpha9 deficiency could be one cause of congenital chylothorax.
Exfoliation and Stability Studies of Germanane and its Derivatives (2014)

Numerous cardiovascular diseases (CVD) eventually lead to severe myocardial dysfunction, which is the most common cause of death worldwide. A better understanding of underlying molecular mechanisms of cardiovascular pathologies seems to be crucial to develop effective therapeutic options. Therefore, a worthwhile endeavor is a detailed molecular characterization of cells extracted from the myocardium. A transcriptomic profile of atrial cardiomyocytes during long-term primary cell culture revealed the expression patterns depending on the duration of the culture and the heart segment of origin (right atrial appendage and right atrium). Differentially expressed genes (DEGs) were classified as involved in ontological groups such as: "cellular component assembly", "cellular component organization", "cellular component biogenesis", and "cytoskeleton organization". Transcriptomic profiling allowed us to indicate the increased expression of <i>COL5A2</i>, <i>COL8A1</i>, and <i>COL12A1</i>, encoding different collagen subunits, pivotal in cardiac extracellular matrix (ECM) structure. Conversely, genes important for cellular architecture, such as <i>ABLIM1</i>, <i>TMOD1</i>, <i>XIRP1</i>, and <i>PHACTR1</i>, were downregulated during in vitro culture. The culture conditions may create a favorable environment for reconstruction of the ECM structures, whereas they may be suboptimal for expression of some pivotal transcripts responsible for the formation of intracellular structures.
Modeling Luminance Perception at Absolute Threshold (2015)

Abstract When human luminance perception operates close to its absolute threshold, i. e., the lowest perceivable absolute values, appearance changes substantially compared to common photopic or scotopic vision. In particular, most observers report perceiving temporally‐varying noise. Two reasons are physiologically plausible; quantum noise (due to the low absolute number of photons) and spontaneous photochemical reactions. Previously, static noise with a normal distribution and no account for absolute values was combined with blue hue shift and blur to simulate scotopic appearance on a photopic display for movies and interactive applications (e.g., games). We present a computational model to reproduce the specific distribution and dynamics of “scotopic noise” for specific absolute values. It automatically introduces a perceptually‐calibrated amount of noise for a specific luminance level and supports animated imagery. Our simulation runs in milliseconds at HD resolution using graphics hardware and favorably compares to simpler alternatives in a perceptual experiment.
Sampling root exudates – Mission impossible? (2018)

Accurate information about the quantity, quality and spatiotemporal dynamics of metabolite release from plant roots is vital to understanding the functional significance of root exudates in biogeochemical processes occurring at the root-microbe-soil-interface. Significant progress in analytical techniques nowadays allows us to gain a much better picture of the rich diversity of compounds that are present in root exudates, but ultimately the choice of exudation sampling strategy will determine the ecological significance of obtained exudation results. Unfortunately, in the past, little consideration has been given to the experimental strategy used to sample root exudates. To date, our knowledge on root exudation is mainly based on plants grown and sampled in nutrient solution culture (hydroponics). Despite the operational benefit of hydroponic systems, the question remains as to how ecologically relevant exudation results obtained under these artificial conditions are compared to soil environments, particularly in the context of exudate driven rhizosphere processes. The quantitative and qualitative measurement of root exudation in soil, however, is fraught with problems due to: (i) continual removal of exudates from solution by the microbial community; (ii) loss of exudates from solution due to their sorption to the solid phase; and (iii) simultaneous release of compounds from soil organic matter breakdown. While a perfect method for sampling root exudates does not exist, soil based approaches, if appropriately applied and interpreted, may still provide more realistic insights into exudation dynamics in natural soil environments. This review aims to provide an overview of different root exudation sampling approaches and their advantages and limitations to support the selection of the most suitable experimental procedure for any specific research question. We address critical methodological aspects that need to be considered in the choice of experimental approach, like growth and sampling medium (soil, hydroponic), sterility, sampling location (whole root system, individual root segments) as well as plant age, daytime, re-uptake of metabolites affecting duration and timing of the sampling event and data presentation. In addition, we summarize the main analytical approaches to analyze root exudates, ranging from liquid sample analysis to isotope tracking and imaging techniques.
A 6-b, 4 GSa/s GaAs HBT ADC (1995)

A GaAs-AlGaAs heterojunction bipolar transistor (HBT) process was developed to meet the speed, gain, and yield requirements for analog-to-digital converters (ADC's). The HBT has current gain of over 100 and f/sub T/ and f/sub MAX/ of over 50 GHz. A 6-b, 4 GSa/s (4 giga-samples/s) ADC was designed and fabricated in this process. The ADC uses an analog folding architecture, includes an on-chip master-slave track-and-hold (T/H) circuit, and provides Gray-encoded digital outputs. The ADC achieves 5.6 effective bits at 4 GSa/s, a faster clock rate than any noninterleaved semiconductor ADC reported to date. It has a resolution bandwidth (the frequency at which effective bits has dropped by 0.5 b) of 1.8 GHz at 4 GSa/s, higher than any published ADC. The chip operates at up to 6.5 GSa/s. GaAs HBT IC's are especially prone to high operating temperatures. This led to reliability problems that were overcome by the use of a fast DC thermal simulator written for this project. A SPICE model for self-heating effects is also described.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">></ETX>
3D printed fiber optic faceplates by custom controlled fused deposition modeling (2018)

A 3D printing technique for manufacturing air-clad coherent fiber optic faceplates is presented. The custom G-code programming is implemented on a fused deposition modeling (FDM) desktop printer to additively draw optical fibers using high-transparency thermoplastic filaments. The 3D printed faceplate consists of 20000 fibers and achieves spatial resolution 1.78 LP/mm. Transmission loss and crosstalk are characterized and compared among the faceplates printed from four kinds of transparent filaments as well as different faceplate thicknesses. The printing temperature is verified by testing the transmission of the faceplates printed under different temperatures. Compared with the conventional stack-and-draw fabrication, the FDM 3D printing technique simplifies the fabrication procedure. The ability to draw fibers with arbitrary organization, structure and overall shape provides additional degree of freedom to opto-mechanical design. Our results indicate a promising capability of 3D printing as the manufacturing technology for fiber optical devices.
Measurement of d<inf>15</inf> shear-mode displacement in ferroelectric PZT film (2009)

d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">15</sub> shear-mode displacements in a ferroelectric PZT(52/48) film could be observed by using a FIB processing and SPM probe measurement for the first time ever. The PZT sample with a beam shape was fabricated by a combination of a sputtering deposition, a FIB machining, and a Cu damascene process. In order to compensate for the effect of constraints arisen from the beam sample structure, FEM simulation analyses were employed. The obtained d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">15</sub> piezoelectric constant of the sputter PZT film was 590 pm/V. The d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">31</sub> piezoelectric constant of the same PZT film was also measured by a conventional tip displacement of cantilever method. The obtained d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">31</sub> value was -120 pm/V. Though the d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">15</sub> value is as large as that of bulk shape, the d <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">31</sub> value was slightly smaller than that of bulk. The difference may be explained that an intrinsic stress existed in the lower portion of the PZT film.
Implementation of system interconnection devices using PCI express (2015)

PCI Express is considered as a good candidate for system interconnects due to its fast speed, low power consumption, and good protocol efficiency. In this paper we propose a system interconnection device based on PCI Express for usage in small-scale system interconnect and describe its design, implementation, and early evaluation. The proposed device provides multiple 20 Gbps connections and current testing results show that the throughput reaches maximally 6.797 Gbps without DMA.