Academic literature on the topic 'Fractional Replicate'

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Journal articles on the topic "Fractional Replicate"

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Zemroch, Peter J. "The Computerized Generation of Fractional-replicate Designs Using Galois Fields and Hadamard Matrices." Quality and Reliability Engineering International 31, no. 7 (August 10, 2015): 1197–207. http://dx.doi.org/10.1002/qre.1846.

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Kahn, S. N., and L. P. Strony. "Imprecision of quantification of serum protein fractions by electrophoresis on cellulose acetate." Clinical Chemistry 32, no. 2 (February 1, 1986): 356–57. http://dx.doi.org/10.1093/clinchem/32.2.356.

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Abstract We studied the precision of densitometric quantification of the protein zones resolved by cellulose acetate electrophoresis. Replicate analyses of patients' samples by a single technologist showed mean CVs ranging from 2.9% for serum albumin to 9.5% for alpha 1-globulin. There were marked differences in measurements obtained by replicate analysis of the same samples by two experienced technologists. We calculated what changes in fractional concentrations would be analytically significant and concluded that densitometry of cellulose acetate electrophoretograms can only be semi-quantitative. We suggest that visual interpretation of high-resolution electrophoretic patterns by a trained observer can replace densitometry in most cases.
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Alharthi, Nadiyah Hussain, Abdon Atangana, and Badr S. Alkahtani. "Numerical analysis of some partial differential equations with fractal-fractional derivative." AIMS Mathematics 8, no. 1 (2022): 2240–56. http://dx.doi.org/10.3934/math.2023116.

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<abstract> <p>In this study, we expanded the partial differential equation framework to which fractal-fractional differentiation can be applied. For this, we employed the generalized Mittag-Leffler function, and the fractal-fractional derivatives based on the power-law kernel. A general partial differential equation with the fractal-fractional derivative, the power law kernel and the generalized Mittag-Leffler function was thoroughly examined. There is almost no numerical scheme for solving partial differential equations with fractal-fractional derivatives, as less investigation has been done in this direction in the last decades. In this work, therefore, we shall attempt to provide a numerical method that might be used to solve these equations in each circumstance. The heat equation was taken into consideration for the application and numerically solved using a few simulations for various values of fractional and fractal orders. It is observed that, when the fractal order is 1, one obtains fractional partial differential equations which have been known to replicate nonlocal behaviors. Meanwhile, if the fractional order is 1, one obtains fractal-partial differential equations. Thus, when the fractional order and fractal dimension are different from zero, nonlocal processes with similar features are developed.</p> </abstract>
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Doungmo Goufo, Emile Franc. "The Proto-Lorenz System in Its Chaotic Fractional and Fractal Structure." International Journal of Bifurcation and Chaos 30, no. 12 (September 30, 2020): 2050180. http://dx.doi.org/10.1142/s0218127420501801.

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It is not common in applied sciences to realize simulations which depict fractal representation in attractors’ dynamics, the reason being a combination of many factors including the nature of the phenomenon that is described and the type of differential operator used in the system. In this work, we use the fractal-fractional derivative with a fractional order to analyze the modified proto-Lorenz system that is usually characterized by chaotic attractors with many scrolls. The fractal-fractional operator used in this paper is a combination of fractal process and fractional differentiation, which is a relatively new concept with most of the properties and features still to be known. We start by summarizing the basic notions related to the fractal-fractional operator. After that, we enumerate the main points related to the establishment of proto-Lorenz system’s equations, leading to the [Formula: see text]th cover of the proto-Lorenz system that contains [Formula: see text] scrolls ([Formula: see text]). The triple and quadric cover of the resulting fractal and fractional proto-Lorenz system are solved using the Haar wavelet methods and numerical simulations are performed. Due to the impact of the fractal-fractional operator, the system is able to maintain its chaotic state of attractor with many scrolls. Additionally, such attractor can self-replicate in a fractal process as the derivative order changes. This result reveals another great feature of the fractal-fractional derivative with fractional order.
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Krehbiel, Timothy C., and Donald A. Anderson. "The use of a monetary loss function to determine the optimal fractional replicate of factorial experiments." Communications in Statistics - Theory and Methods 21, no. 8 (January 1992): 2383–98. http://dx.doi.org/10.1080/03610929208830919.

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Faridi, Waqas Ali, Muhammad Imran Asjad, Shabir Ahmad, Adrian Iftene, Magda Abd El-Rahman, and Mohammed Sallah. "Deterministic and Fractional-Order Co-Infection Model of Omicron and Delta Variants of Asymptomatic SARS-CoV-2 Carriers." Fractal and Fractional 7, no. 2 (February 14, 2023): 192. http://dx.doi.org/10.3390/fractalfract7020192.

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The Delta and Omicron variants’ system was used in this research study to replicate the complex process of the SARS-CoV-2 outbreak. The generalised fractional system was designed and rigorously analysed in order to gain a comprehensive understanding of the transmission dynamics of both variants. The proposed dynamical system has heredity and memory effects, which greatly improved our ability to perceive the disease propagation dynamics. The non-singular Atangana–Baleanu fractional operator was used to forecast the current pandemic in order to meet this challenge. The Picard recursions approach can be used to ensure that the designed fractional system has at least one solution occupying the growth condition and memory function regardless of the initial conditions. The Hyers–Ulam–Rassias stability criteria were used to carry out the stability analysis of the fractional governing system of equations, and the fixed-point theory ensured the uniqueness of the solution. Additionally, the model exhibited global asymptotically stable behaviour in some conditions. The approximate behaviour of the fatal virus was investigated using an efficient and reliable fractional numerical Adams–Bashforth approach. The outcome demonstrated that there will be a significant decline in the population of those infected with the Omicron and Delta SARS-CoV-2 variants if the vaccination rate is increased (in both the symptomatic and symptomatic stages).
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Escribano-García, Ruben, Pedro Álvarez, and David Marquez-Monje. "Calibration of Finite Element Model of Titanium Laser Welding by Fractional Factorial Design." Journal of Manufacturing and Materials Processing 6, no. 6 (October 26, 2022): 130. http://dx.doi.org/10.3390/jmmp6060130.

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This paper focuses on the calibration of heat source parameters to reproduce temperatures and distortions in welded joints. Specifically, the proposed methodology, which combines the Finite Element Method and Design of Experiments, is applied to calibrate a T-joint dissimilar titanium laser welding process. The thermal problem is addressed using a 3D transient model with a Conical Gaussian heat flux, and the mechanical problem is tackled using a 3D elastic-plastic model. A Fractional-Factorial Design is performed to define a set of thermo-mechanical uncoupled models. Finally, optimal parameter combinations that replicate experimental data are identified. This methodology allows automation that replaces the traditional trial and error process, which frequently does not provide good results, is an exhausting task and requires a dubious amount of time.
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Mandapati, Vinny Cris, Harsh Vardhan, Shashi Prabhakar, Sakshi, Ravi Kumar, Salla Gangi Reddy, Ravindra P. Singh, and Kehar Singh. "Multi-User Nonlinear Optical Cryptosystem Based on Polar Decomposition and Fractional Vortex Speckle Patterns." Photonics 10, no. 5 (May 11, 2023): 561. http://dx.doi.org/10.3390/photonics10050561.

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In this paper, we propose a new multiuser nonlinear optical cryptosystem using fractional-order vortex speckle (FOVS) patterns as security keys. In conventional optical cryptosystems, mostly random phase masks are used as the security keys which are prone to various attacks such as brute force attack. In the current study, the FOVSs are generated optically by the scattering of the fractional-order vortex beam, known for azimuthal phase and helical wavefronts, through a ground glass diffuser. FOVSs have a remarkable property that makes them almost impossible to replicate. In the input plane, the amplitude image is first phase encoded and then modulated with the FOVS phase mask to obtain the complex image. This complex image is further processed to obtain the encrypted image using the proposed method. Two private security keys are obtained through polar decomposition which enables the multi-user capability in the cryptosystem. The robustness of the proposed method is tested against existing attacks such as the contamination attack and known-plaintext attack. Numerical simulations confirm the validity and feasibility of the proposed method.
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Chacko, Shaji K., Agneta L. Sunehag, Susan Sharma, Pieter J. J. Sauer, and Morey W. Haymond. "Measurement of gluconeogenesis using glucose fragments and mass spectrometry after ingestion of deuterium oxide." Journal of Applied Physiology 104, no. 4 (April 2008): 944–51. http://dx.doi.org/10.1152/japplphysiol.00752.2007.

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We report a new method to measure the fraction of glucose derived from gluconeogenesis using gas chromatography-mass spectrometry and positive chemical ionization. After ingestion of deuterium oxide by subjects, glucose derived from gluconeogenesis is labeled with deuterium. Our calculations of gluconeogenesis are based on measurements of the average enrichment of deuterium on carbon 1, 3, 4, 5, and 6 of glucose and the deuterium enrichment in body water. In a sample from an adult volunteer after ingestion of deuterium oxide, fractional gluconeogenesis using the “average deuterium enrichment method” was 48.3 ± 0.5% (mean ± SD) and that with the C-5 hexamethylenetetramine (HMT) method by Landau et al. (Landau BR, Wahren J, Chandramouli V, Schumann WC, Ekberg K, Kalhan SC; J Clin Invest 98: 378–385, 1996) was 46.9 ± 5.4%. The coefficient of variation of 10 replicate analyses using the new method was 1.0% compared with 11.5% for the C-5 HMT method. In samples derived from an infant receiving total parenteral nutrition, fractional gluconeogenesis was 13.3 ± 0.3% using the new method and 13.7 ± 0.8% using the C-5 HMT method. Fractional gluconeogenesis measured in six adult volunteers after 66 h of continuous fasting was 83.7 ± 2.3% using the new method and 84.2 ± 5.0% using the C-5 HMT method. In conclusion, the average deuterium enrichment method is simple, highly reproducible, and cost effective. Furthermore, it requires only small blood sample volumes. With the use of an additional tracer, glucose rate of appearance can also be measured during the same analysis. Thus the new method makes measurements of gluconeogenesis available and affordable to large numbers of investigators under conditions of low and high fractional gluconeogenesis (∼10 to ∼90) in all subject populations.
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FUNAHASHI, HIDEHARU. "REPLICATION SCHEME FOR THE PRICING OF EUROPEAN OPTIONS." International Journal of Theoretical and Applied Finance 24, no. 03 (May 2021): 2150014. http://dx.doi.org/10.1142/s021902492150014x.

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This paper proposes an efficient method for calculating European option prices under local, stochastic, and fractional volatility models. Instead of directly calculating the density function of a target underlying asset, we replicate it from a simpler diffusion process with a known analytical solution for the European option. For this purpose, we derive six functions that characterize the density function of a diffusion process, for both the original and simpler processes and match these functions so that the latter mimics the former. Using the analytical formula, we then approximate the option price of the target asset. By comparison with previous works and numerical experiments, we show that the accuracy of our approximation is high, and the calculation is fast enough for practical purposes; hence, it is suitable for calibration purposes.
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Dissertations / Theses on the topic "Fractional Replicate"

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Huang, Won-Chin Liao. "Applications of the Chinese Remainder Theorem to the construction and analysis of confounding systems and randomized fractional replicates for mixed factorial experiments." Diss., Virginia Polytechnic Institute and State University, 1989. http://hdl.handle.net/10919/54195.

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A well-known theorem in "Number Theory", the Chinese Remainder Theorem, was first utilized by Paul K. Lin in constructing confounding systems for mixed factorial experiments. This study extends the use of the theorem to cover cases when more than one component from some of the symmetrical factorials are confounded, and to include cases where the number of levels of factors are not all relative prime. The second part of this study concerns the randomized fractional replicates, a procedure which selects confounded subsets with pre-assigned probabilities. This procedure provides full information on a specific set of parameters of interest while making no assumption of zero nuisance parameters. Estimation procedures in general symmetrical as well as asymmetrical factorial systems are studied under a ”fully orthogonalized" model. The type-g estimator, investigated under the generalized inverse operator, and the class of linear estimators of parameters of interest and their variance-covariance matrices are given. The unbiasedness of these estimators can be obtained only under the condition that each subset of treatment combinations is selected with equal probability. This work is concluded with simulation studies to compare the classical and the randomization procedures. The results indicate that when information about the nuisance parameters is not available, randomization procedure guards against a bad choice of design.
Ph. D.
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Krishna, Ram. "Microstructural investigation of alloys used for power generation industries." Thesis, University of Leicester, 2010. http://hdl.handle.net/2381/8601.

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Nickel based superalloys are currently being investigated for high temperature applications in advanced steam power plant operating at temperatures of 700˚C and above. Three nickel-based superalloys Inconel 617, Inconel 625 and Nimonic 263 alloys, which are of primary interest for boiler technology components such as furnace walls, superheater tubes, header and steam pipes, etc and for steam turbine technology components such as HP &IP cylinders, rotor forgings, casing and valve chest, blading, etc., have been evaluated for long and short term creep performance. Creep deformation processes occurring at high temperatures and stresses lead to the evolution of microstructures in the form of precipitation, precipitate coarsening and recovery effects. The deterioration in mechanical properties as a result of this microstructural change has been evaluated by hardness testing. This work discusses the microstructural evolution occurring in alloys in samples that have been creep exposed at a series of temperatures from 650°C to 775°C and for durations from 1000 to 45,000 hours using advanced FEGSEM, TEM, XRD and phase extraction techniques. The fractions and morphology of different phases, their locations during exposure to higher temperatures and probable creep fracture mechanism in these alloys are illustrated and discussed.
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Mugisha, Stella. "Applied mathematical modelling with new parameters and applications to some real life problems." Thesis, 2018. http://hdl.handle.net/10500/24973.

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Some Epidemic models with fractional derivatives were proved to be well-defined, well-posed and more accurate [34, 51, 116], compared to models with the conventional derivative. An Ebola epidemic model with non-linear transmission is fully analyzed. The model is expressed with the conventional time derivative with a new parameter included, which happens to be fractional (that derivative is called the 􀀀derivative). We proved that the model is well-de ned and well-posed. Moreover, conditions for boundedness and dissipativity of the trajectories are established. Exploiting the generalized Routh-Hurwitz Criteria, existence and stability analysis of equilibrium points for the Ebola model are performed to show that they are strongly dependent on the non-linear transmission. In particular, conditions for existence and stability of a unique endemic equilibrium to the Ebola system are given. Numerical simulations are provided for particular expressions of the non-linear transmission, with model's parameters taking di erent values. The resulting simulations are in concordance with the usual threshold behavior. The results obtained here may be signi cant for the ght and prevention against Ebola haemorrhagic fever that has so far exterminated hundreds of families and is still a ecting many people in West-Africa and other parts of the world. The full comprehension and handling of the phenomenon of shattering, sometime happening during the process of polymer chain degradation [129, 142], remains unsolved when using the traditional evolution equations describing the degradation. This traditional model has been proved to be very hard to handle as it involves evolution of two intertwined quantities. Moreover, the explicit form of its solution is, in general, impossible to obtain. We explore the possibility of generalizing evolution equation modeling the polymer chain degradation and analyze the model with the conventional time derivative with a new parameter. We consider the general case where the breakup rate depends on the size of the chain breaking up. In the process, the alternative version of Sumudu integral transform is used to provide an explicit form of the general solution representing the evolution of polymer sizes distribution. In particular, we show that this evolution exhibits existence of complex periodic properties due to the presence of cosine and sine functions governing the solutions. Numerical simulations are performed for some particular cases and prove that the system describing the polymer chain degradation contains complex and simple harmonic poles whose e ects are given by these functions or a combination of them. This result may be crucial in the ongoing research to better handle and explain the phenomenon of shattering. Lastly, it has become a conjecture that power series like Mittag-Le er functions and their variants naturally govern solutions to most of generalized fractional evolution models such as kinetic, di usion or relaxation equations. The question is to say whether or not this is always true! Whence, three generalized evolution equations with an additional fractional parameter are solved analytically with conventional techniques. These are processes related to stationary state system, relaxation and di usion. In the analysis, we exploit the Sumudu transform to show that investigation on the stationary state system leads to results of invariability. However, unlike other models, the generalized di usion and relaxation models are proven not to be governed by Mittag-Le er functions or any of their variants, but rather by a parameterized exponential function, new in the literature, more accurate and easier to handle. Graphical representations are performed and also show how that parameter, called ; can be used to control the stationarity of such generalized models.
Mathematical Sciences
Ph. D. (Applied Mathematics)
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Book chapters on the topic "Fractional Replicate"

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Zemroch, P. J. "KEYFINDER — A Complete Toolkit for Generating Fractional-Replicate and Blocked Factorial Designs." In Computational Statistics, 263–68. Heidelberg: Physica-Verlag HD, 1992. http://dx.doi.org/10.1007/978-3-642-48678-4_33.

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"Sequences of Fractional Replicates." In Wiley Series in Probability and Statistics, 241–50. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2011. http://dx.doi.org/10.1002/9780470316467.ch14.

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Arnold, Stevan J. "Evolution of a Single Trait on a Stationary Adaptive Landscape." In Evolutionary Quantitative Genetics, 226–35. Oxford University PressOxford, 2023. http://dx.doi.org/10.1093/oso/9780192859389.003.0013.

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Abstract The adaptive landscape is a powerful tool for conceptualizing and modelling long-term responses to selection. Here we focus on a single trait evolving on an adaptive landscape with a single, stationary peak. To visualize the stochastic models that we will use, imagine a set of replicate populations of identical size that descend all at once from a common ancestor and thereafter evolve on identical adaptive landscapes. A ∩-shaped adaptive landscape results in a stable equilibrium distribution of the replicate trait means. Stabilizing selection tends to pull the mean towards a peak on the landscape, but that tendency is balanced by drift of the trait mean away from the peak. As a consequence of this push-pull dynamic, once all the replicates have achieved an equilibrium, variation among their trait means is inversely proportional to effective population size. The smaller the size of each replicate, the more variable the response to selection. Tests of model predictions with large data sets indicate that this Ornstein-Uhlenbeck (OU) model is undoubtedly an element in the general explanation for stasis, but other factors are also in play. In particular, the OU model with realistic parameter produces only a fraction of the differentiation that is observed in nature. Parameter fits are even worse for peak-shift models. As we shall see in later chapters, stabilizing selection helps explain stasis, but we also need a model for the movement of the peak.
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Ferreira, Assel Muratovna Shigayeva, Lucas de Almeida Moura, and Neir Antunes Paes. "Estimation of excess mortality during COVID-19 pandemic based on death registry quality analysis." In EMERGING ISSUES RELATED TO THE CORONA VIRUS PANDEMIC (COVID 19). Seven Editora, 2023. http://dx.doi.org/10.56238/emerrelcovid19-050.

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Background: There was a debate whether an accurate measurement of deaths was exacerbated during COVID-19 pandemic 2020 in Brazil. Purpose: This study aimed to analyze the magnitude and temporal course of excess mortality from the COVID-19 pandemic in 2020 with evaluation of mortality data quality in one state of Northeast region of Brazil. Methods: Excess mortality estimation and evaluation of the quality of COVID-19 death records during 2020 pandemic was applied for the state of Paraiba. The assessment of deaths records quality included analysis of its coverage and completeness (redistribution of garbage codes (GCs) with redistribution of ill-defined causes). Results: The total number of deaths due COVID-19 in Paraiba for 2020 increased by 37.4% after data quality correction analysis. The study proved statistically significant excess of deaths in the state for all-cause mortality and natural causes, with approximately 2-fold higher number for respiratory diseases. The quality data correction added significant fractions on top of initially observed deaths which makes the scope of exceeding deaths in Paraiba even larger. Conclusions. There is strong evidence that the full impact of the 2020 pandemic in Paraiba has been much greater than what is indicated by reported deaths due to COVID-19 alone. It is noteworthy that the methodology applied to the state of Paraiba can be replicated for any Brazilian state.
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"The easiest way of detecting specific nucleic acid sequences or genes of interest is through direct hybridization of a probe to microbial nucleic acid extracts. Whole-cell DNA or RNA is extracted from the environmental sample and fixed to a positively charged membrane, e.g. nylon or nitrocellulose. Bacterial colonies can also be replica-plated from agar plates to membranes and their nucleic acids exposed in situ following lysis for subsequent hybridization. Probes may be used to detect genes in the bacterial genome (Southern blots) or to detect mRNA or rRNA (Northern blots). For the in situ identification of individual whole cells it is necessary to make the cells permeable to oligonucleotide probes hybridizing with rRNA. These hybridization techniques rely on the specific binding of nucleic acid probes to complementary DNA or RNA (target nucleic acid). The probes are single strands of nucleic acid with the potential of carrying detectable marker molecules highly specifically to complementary target sequences, even if these sequences account for only a small fraction of the target nucleic acid. Either DNA or RNA can serve as a nucleic acid probe, but for a number of reasons (e.g. ease of synthesis and stability), most studies have employed DNA probes (Holben and Hedje 1988). Two general types of probes that have been developed are DNA probes complementary to a single gene or a small region of a gene and DNA probes complementary to genus- or species-specific regions of 16S rRNA for use in whole cell in situ hybridization (FISH)." In Recent Advances in Marine Biotechnology, Vol. 8, 224. CRC Press, 2003. http://dx.doi.org/10.1201/9781482279986-17.

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Conference papers on the topic "Fractional Replicate"

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Albadawi, Muhamed, Yasser Abuouf, Samir Elsagheer, Hidetoshi Sekiguchi, Shinichi Ookawara, and Mahmoud Ahmed. "Is the Blood Flow Laminar or Turbulent at Stenosed Coronary Artery?" In ASME 2022 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2022. http://dx.doi.org/10.1115/imece2022-95594.

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Abstract Coronary artery disease (CAD) is the abnormal contraction of heart supply blood vessel. This contraction in the blood vessels limits the flow of oxygenated blood to the heart. Thus, diagnosing its severity helps physicians to select the appropriate treatment plan. Most of the commonly diagnostic methods are qualitative. They depend on the physicians’ experience and judgement to specify the severity of the stenoses. Fractional flow reserve is one of the quantitative diagnostic tools used while coronary catheterization is being performed. Fractional flow reserve measures the pressure gradient from the proximal to the distal sides of a coronary artery stenosis; this helps in deciding whether the stenosis limits the oxygenated blood flow. Resent models of vascular hemodynamics consider physiologic blood flow to be laminar. Transition to turbulence is considered as a driving factor for numerous diseases such as stenosis and aneurysm. As the value of Reynolds number does not exceed 2000, the flow is laminar. Several researchers stated that the flow might be turbulent at critical Reynolds number value less than 2000. Hence, the aim of this study is to investigate the most accurate turbulence flow model compared to the available experimental data. It is important to replicate the experimental model. Accordingly, the same non-Newtonian blood flow model and pulsatile flow boundary conditions were used. The stenosed simple geometry with a centered fractional flow reserve guidewire is constructed based on the same dimensions of the experimental setup. The numerical models were simulated with laminar flow and K-ε, and large eddy simulation (LES) turbulence modelling. The predicted results are compared with the actual available experimental measurements to investigate the most accurate numerical model of the blood flow in the stenosed coronary artery. Based on the predicted results, pressure drop coefficient (CDP), Pressure recovery coefficient (CPR), and the pressure recovery factor η are investigated in the coronary stenosis with and without fractional flow reserve guidewire. For the severe 89% stenosis, it was found that the error in CDP before and during the guidewire insertion is small. The error in CDP before inserting the guidewire reached −7%, −7%, and −12% for laminar, turbulent K-ε, and LES models, respectively and −11%, −11%, and −4% for laminar, turbulent K-ε, and LES models, respectively during inserting the guidewire. Accordingly, it can be concluded that the laminar and LES modelling represent better performance in simulating the blood flow rather than the turbulence model.
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Ennin, Edward. "Carbon Dioxide Sequestration and Drainage in Saline Aquifer." In SPE Trinidad and Tobago Section Energy Resources Conference. SPE, 2021. http://dx.doi.org/10.2118/200911-ms.

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Abstract Geological storage of CO2 in saline aquifers is recognized as a favorable technique that could deliver a significant decrease in CO2 emissions over the short to medium-term. However, the major risk is the possibility of leakage and injection limitation due to pore pressure. This research investigates the three major mechanisms of CO2 trapping to determine which method safely captures the most CO2, interrogates the pore pressure effect on storage, and compares traditional core flooding methods for CO2 storage with CO2 drainage which is more practical in the aquifer. A core flooding set up was built to replicate reservoir conditions of the Anadarko Basin in Texas, USA. The research involved three reservoir pay zone rocks obtained from depths of about 7687ft that were pieced together to undergo core flooding at 4400psi-5200psi and a temperature of 168°F. In the first study conducted the core was flooded with supercritical CO2 and brine of salinity 4000ppm to generate relative permeability curves to represent drainage and imbibition. For the duration of the 3rd, 4th, and 5th studies the core saturated with brine is flooded with CO2 at pressures of 4400psi, 4800psi, and 5200psi. Parameters like the volume of CO2 captured, connate water volumes, differential pressure, Ph of produced water, trapping efficiency, relative permeability, and fractional flow curves are noted. After scrutinizing the result it is observed that the highest volume of CO2 is captured by solubility trapping followed by structural trapping and residual trapping in that order. From this research, it can be concluded that CO2 trapping, at least for these reservoir rocks, is not affected by pore pressure. Also contrary to most practices CO2 storage is best replaced in the laboratory using drainage experiments instead of the widely used relative permeability approach.
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Faria, Danilo Donizete de, Joselisa Péres Queiroz de Paiva, Artur Jose Marques Paulo, Sonia Maria Cesar de Azevedo Gomes, Vanderci Borges, Henrique Ballalai Ferraz, and Patrícia Maria de Carvalho Aguiar. "Structural MRI analysis of basal ganglia volume and white matter tracts in upper limb dystonia." In XIV Congresso Paulista de Neurologia. Zeppelini Editorial e Comunicação, 2023. http://dx.doi.org/10.5327/1516-3180.141s1.547.

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Background: Dystonia is known as a network disorder. There is evidence of volumetric changes in structures associated with the traditional physiopathology, such as basal nuclei. One approach to studying the neural pathways is through tractography, which can provide insights into the structural connectivity of neural networks that may be disrupted in dystonia. Objectives: To evaluate brain structural changes of motor networks and basal ganglia volume in dystonia. Methods: Twenty-six patients with right upper limb dystonia and 29 healthy controls underwent 3T magnetic resonance imaging and evaluated in terms of DTI and T1 data. The XTRACT FSL tool was utilized to examine fractional anisotropy of the bilateral anterior thalamic radiation, superior thalamic radiation, superior longitudinal fasciculus, cortical spinal tract, middle cerebellar peduncle, forceps major and forceps minor. Using T1-weithed data, volunteers were also evaluated in terms of volumetric changes in bilateral Putamen, Caudate, Pallidum and Thalamus extracted using Freesurfer 7.0 volumetric segmentation. For group comparison, we conducted an analysis of covariance controlling for sex and estimated intracranial volume. Results: For uncorrected p-values, patients with upper limb dystonia show diminished FA volume in the right corticospinal tract relative to controls (P = 0.025). Region of interest analysis of subcortical regions volume based on T1-weighted images shows that patients had diminished left caudate volume (P = 0.031) and right putamen (P = 0.041). However, using FDR multiple comparisons correction, no difference was observed between groups: right corticospinal tract (P = 0.329), left caudate volume (P = 0.16), right putamen volume (P = 0.16). Conclusion: Our study could not replicate previous findings describing structural changes in dystonia. This could be to methodological differences, as well as the fact that we selected only patients with upper limb dystonia, as opposed to studies that included other types of dystonia. The neuroimaging analyses were conducted with the utmost rigor, utilizing the optimal preprocessing and statistical analysis methods. The nature and characteristics of structural alterations remain unclear and may vary depending on the subtype of dystonia. Therefore, additional structural studies and meta-analyses are warranted to advance our knowledge of this network disorder.
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Liu, Yu-Cheng, Anthony J. Savas, and C. Thomas Avedisian. "The Combustion Characteristics of n-Decane/Iso-Octane/Toluene Mixture and Jet-A Fuel Droplets in the Absence of Convection." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-64495.

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This study examines the extent to which a ternary mixture of n-decane/iso-octane/toluene in the specific mixture fraction of 42.67/33.02/24.31 (mole fraction), respectively, can replicate the droplet burning characteristics of an aviation fuel, Jet-A (designated by the Air Force as “POSF4658”). Experiments were carried out to examine the droplet combustion characteristics in an environment which minimizes convection to promote spherical symmetry in the burning process. The evolution of droplet diameter, burning rate and flame and soot stand-off ratios were compared to Jet-A to evaluate the potential of this ternary to serve as a Jet-A surrogate regarding the droplet burning process. The results show that the ternary blend has a shorter transient droplet heating period than Jet-A and it closely replicates the evolution of droplet diameter and burning rate. The burning rates for these two fuels are close at the end of burning, and flame and soot standoff ratios for the ternary are also reasonably close to those of Jet-A. The results also suggest that the spherical droplet flame configuration can be a useful tool to evaluate the extent to which a mixture of single component fuels may serve as a surrogate of a real transportation fuel.
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Rojas, Allan A., Chengdong Yuan, Dmitrii A. Emelianov, Emil R. Saifullin, Seyedsaeed Mehrabi-Kalajahi, Mikhail A. Varfolomeev, Vladislav A. Sudakov, et al. "A 3-Step Reaction Model For Numerical Simulation of In-Situ Combustion." In SPE Russian Petroleum Technology Conference. SPE, 2021. http://dx.doi.org/10.2118/206430-ms.

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Abstract In-situ combustion (ISC) is an effective thermal enhanced oil recovery method. However, it is still not widely implemented in oilfields. One of the factors limiting the wide application of ISC is the challenge in its simulation and prediction. In this work, the oxidation experiments of maltenes and asphaltenes in reservoir rock were performed in the porous media thermo-effect cell (PMTEC) to establish a simplified reaction model based on non-isothermal measurements and to use it in numerical simulation of ISC process. It was found that the oxidation reaction process of oil fractions can be divided into different regions depending on generated self-energy rate and oxygen consumption rates that is up to the temperature. In order to propagate reactions from one mode to another, a specific oxygen consumption per unit mass of oil fractions is required. The average oxygen requirement for crossing LTOad (low temperature oxidation, oxygen addition reactions) boundary into LTC (low temperature combustion) mode was 64 mgO2/g(maltenes) and 10.4 mgO2/g(asphaltenes). To propagate reactions into HTO mode from the LTC mode, it requires about 646 mgO2/g(asphaltenes) for asphaltenes fraction. Moreover, this characterization seems to be a key tool when designing air injection in field pilots. Additionally, it was revealed that asphaltenes are more exothermic and require lower oxygen uptake per unit of temperature increment in comparison to maltenes. Furthermore, the mass conversion data obtained from non-isothermal measurements of oil fractions allow for the estimation of the stoichiometry coefficients of two low temperature oxidation reactions, i.e. oxidation and cocking processes, which can be included into a numerical simulation model to replicate combustion tube (CT) results. The numerical simulation model reveals that the simplified reaction model from a 6-step into a 3-step reaction scheme can reproduce ignition process, temperature profiles, combustion velocity, and fluid production, which thus makes it suitable for the upscaled modelling of ISC.
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Daly, Michael, Fabien Leonard, and Andrew H. Sherry. "Application of 3D X-Ray Tomography to Enhance the Calibration of Ductile Fracture Models." In ASME 2014 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/pvp2014-28318.

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Reactor Pressure Vessels (RPV) are manufactured from medium strength low allow ferritic steel specifically selected for its high toughness and weldability. The normal operating temperature of RPV steels is sufficiently high to ensure that the material remains ductile throughout its service life with an extremely low probability of cleavage under normal and off-normal loading conditions. Understanding and having the ability to predict ductile fracture behaviour is consequently important. The ductile fracture mechanism is characterised by the nucleation, growth and coalescence of voids at initiating particles within the volume of high triaxial stress and plastic strain ahead of a crack-tip or stress concentrator. The fracture properties of the steels are conventionally determined using standard pre-cracked compact test specimens. Mechanistically based models of fracture can be calibrated against those data. This paper describes the use of 3D laboratory X-ray tomography to characterise the void distribution associated with the ductile fracture in test specimens and use the data to calibrate the Gurson-Tvergaard-Needleman ductile fracture model. The tomography successfully captures voids ≥ 6um in diameter and has been used to define the average distribution of void volume fraction as a function of distance below the fracture surface. The tomography results also allow an estimate of the critical and final void volume fractions to be made as well as capture secondary void peaks well below the fracture surface. This distribution of voids was used to calibrate the Gurson-Tvergaard-Needleman model in order to correlate experimental observations with the finite element models. The models have been able to replicate the observed trends of the void volume fraction distributions away from the fracture surface including the secondary peaks observed by tomography and to reproduce similar J-R curve behaviour as that observed in the test specimens.
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Lin, Chun-Yu, Yu-Ting Hung, Tun-Ju Wang, and Tsung-Hsien Lin. "29.5 A 0.008mm2 1.5mW 0.625-to-200MHz Fractional Output Divider with 120fsrms Jitter Based on Replica-DTC-Free Background Calibration." In 2021 IEEE International Solid- State Circuits Conference (ISSCC). IEEE, 2021. http://dx.doi.org/10.1109/isscc42613.2021.9365821.

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Restrepo, Bernardo, Larry E. Banta, and David Tucker. "Characterization of a Solid Oxide Fuel Cell Gas Turbine Hybrid System Based on a Factorial Design of Experiments Using Hardware Simulation." In ASME 2011 9th International Conference on Fuel Cell Science, Engineering and Technology collocated with ASME 2011 5th International Conference on Energy Sustainability. ASMEDC, 2011. http://dx.doi.org/10.1115/fuelcell2011-54146.

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A full factorial experimental design and a replicated fractional factorial design were carried out using the Hybrid Performance (HyPer) project facility installed at the National Energy Technology Laboratory (NETL), U.S. Department of Energy to simulate gasifer/fuel cell/turbine hybrid power systems. The HyPer facility uses hardware in the loop (HIL) technology that couples a modified recuperated gas turbine cycle with hardware driven by a solid oxide fuel cell model. A 34 full factorial design (FFD) was selected to study the effects of four factors: cold-air, hot-air, bleed-air bypass valves, and the electric load on different parameters such as cathode and turbine inlet temperatures, pressure and mass flow. The results obtained, compared with former results where the experiments were made using one-factor-at-a-time (OFAT), show that no strong interactions between the factors are present in the different parameters of the system. This work also presents a fractional factorial design (ffd) 34-2 in order to analyze replication of the experiments. In addition, a new envelope is described based on the results of the design of experiments (DoE), compared with OFAT experiments, and analyzed in an off-design integrated fuel cell/gas turbine framework. This paper describes the methodology, strategy, and results of these experiments that bring new knowledge concerning the operating state space for this kind of power generation system.
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Kim, Mina, Seojin Choi, and Jaehyouk Choi. "A 450-fs jitter PVT-robust fractional-resolution injection-locked clock multiplier using a DLL-based calibrator with replica-delay-cells." In 2015 Symposium on VLSI Circuits. IEEE, 2015. http://dx.doi.org/10.1109/vlsic.2015.7231356.

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Sarich, Conner, Adam Hope, and Jim Rule. "Optimization of Interfacial Energy for Langer-Schwartz Based Precipitation Simulations." In HT2021. ASM International, 2021. http://dx.doi.org/10.31399/asm.cp.ht2021exabp0076.

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Abstract Precipitation kinetics were investigated in select Fe, Ni, and Al alloys using a CALPHAD based precipitation model based on Langer-Schwartz theory. Thermodynamic and kinetic data are taken from commercially available CALPHAD software, but reliable interfacial energy data for precipitates needed for the calculations is often lacking. While models exist to approximate these interfacial energies, this study has focused on deriving more reliable estimates by comparison with experimental data. By performing simulations with thermal histories, nucleation sites, and precipitate morphologies that closely replicate experimental data found in literature, the interfacial energies were optimized until volume fraction and mean radius values closely matched the published data. Using this technique, interfacial energy values have been determined for carbides in Grade 22 low alloy steels, delta phase in Ni 625 and 718, SPhase in Al 2024, and Q’ and β’’ in Al 6111, and can be used for future predictive precipitation simulations.
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Reports on the topic "Fractional Replicate"

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Knight, R. D., and B. A. Kjarsgaard. Comparative pXRF and Lab ICP-ES/MS methods for mineral resource assessment, Northwest Territories. Natural Resources Canada/CMSS/Information Management, 2022. http://dx.doi.org/10.4095/331239.

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The Geological Survey of Canada undertook a mineral resource assessment for a proposed national park in northern Canada (~ 33,500 km2) spanning the transition from boreal forest to barren lands tundra. Bedrock geology of this region is complex and includes the Archean Slave Craton, the Archean and Paleoproterozoic Rae domain of the Churchill Province, the Paleoproterozoic Thelon and Taltson magmatic-tectonic zones, and the Paleoproterozoic East Arm sedimentary basin. The area has variable mineral potential for lode gold, kimberlite-hosted diamonds, VMS, vein uranium and copper, SEDEX, as well as other deposit types. A comparison of analytical methods was carried out after processing the field collected samples to acquire both the &amp;lt; 2 mm and for the &amp;lt; 0.063 mm size fractions for 241 surficial sediment (till) samples, collected using a 10 x 10 km grid. Analytical methods comprised: 1) aqua regia followed by ICP-MS analysis, 2) 4-acid hot dissolution followed by ICP-ES/MS analysis, 3) lithium metaborate/tetraborate fusion methods followed by ICP-ES for major elements and ICP-MS for trace elements and, 4) portable XRF on dried, non-sieved sediment samples subjected to a granular segregation processing technique (to produce a clay-silt proxy) for seventeen elements (Ba, Ca, Cr, Cu, Fe, K, Mn, Ni, Pb, Rb, Sr, Th, Ti, U, V, Zn, and Zr) Results indicate that pXRF data do not replicate exactly the laboratory 4-acid and fusion data (in terms of precision and accuracy), but the relationship between the datasets is systematic as displayed in x-y scattergrams. Interpolated single element plots indicate that till samples with anomalies of high and low pXRF concentration levels are synonymous with high and low laboratory-based analytical concentration levels, respectively. The pXRF interpolations thus illustrate the regional geochemical trends, and most importantly, the significant geochemical anomalies in the surficial samples. These results indicate that pXRF spectrometry for a subset of elements is comparable to traditional laboratory methods. pXRF spectrometry also provides the benefit of rapid analysis and data acquisition that has a direct influence on real time sampling designs. This information facilitates efficient and cost-effective field projects (i.e. where used to identify regions of interest for high density sampling), and to prioritize samples to be analyzed using traditional geochemical methods. These tactics should increase the efficiency and success of a mineral exploration and/or environmental sampling programs.
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Epel, Bernard L., Roger N. Beachy, A. Katz, G. Kotlinzky, M. Erlanger, A. Yahalom, M. Erlanger, and J. Szecsi. Isolation and Characterization of Plasmodesmata Components by Association with Tobacco Mosaic Virus Movement Proteins Fused with the Green Fluorescent Protein from Aequorea victoria. United States Department of Agriculture, September 1999. http://dx.doi.org/10.32747/1999.7573996.bard.

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The coordination and regulation of growth and development in multicellular organisms is dependent, in part, on the controlled short and long-distance transport of signaling molecule: In plants, symplastic communication is provided by trans-wall co-axial membranous tunnels termed plasmodesmata (Pd). Plant viruses spread cell-to-cell by altering Pd. This movement scenario necessitates a targeting mechanism that delivers the virus to a Pd and a transport mechanism to move the virion or viral nucleic acid through the Pd channel. The identity of host proteins with which MP interacts, the mechanism of the targeting of the MP to the Pd and biochemical information on how Pd are alter are questions which have been dealt with during this BARD project. The research objectives of the two labs were to continue their biochemical, cellular and molecular studies of Pd composition and function by employing infectious modified clones of TMV in which MP is fused with GFP. We examined Pd composition, and studied the intra- and intercellular targeting mechanism of MP during the infection cycle. Most of the goals we set for ourselves were met. The Israeli PI and collaborators (Oparka et al., 1999) demonstrated that Pd permeability is under developmental control, that Pd in sink tissues indiscriminately traffic proteins of sizes of up to 50 kDa and that during the sink to source transition there is a substantial decrease in Pd permeability. It was shown that companion cells in source phloem tissue export proteins which traffic in phloem and which unload in sink tissue and move cell to cell. The TAU group employing MP:GFP as a fluorescence probe for optimized the procedure for Pd isolation. At least two proteins kinases found to be associated with Pd isolated from source leaves of N. benthamiana, one being a calcium dependent protein kinase. A number of proteins were microsequenced and identified. Polyclonal antibodies were generated against proteins in a purified Pd fraction. A T-7 phage display library was created and used to "biopan" for Pd genes using these antibodies. Selected isolates are being sequenced. The TAU group also examined whether the subcellular targeting of MP:GFP was dependent on processes that occurred only in the presence of the virus or whether targeting was a property indigenous to MP. Mutant non-functional movement proteins were also employed to study partial reactions. Subcellular targeting and movement were shown to be properties indigenous to MP and that these processes do not require other viral elements. The data also suggest post-translational modification of MP is required before the MP can move cell to cell. The USA group monitored the development of the infection and local movement of TMV in N. benthamiana, using viral constructs expressing GFP either fused to the MP of TMV or expressing GFP as a free protein. The fusion protein and/or the free GFP were expressed from either the movement protein subgenomic promoter or from the subgenomic promoter of the coat protein. Observations supported the hypothesis that expression from the cp sgp is regulated differently than expression from the mp sgp (Szecsi et al., 1999). Using immunocytochemistry and electron microscopy, it was determined that paired wall-appressed bodies behind the leading edge of the fluorescent ring induced by TMV-(mp)-MP:GFP contain MP:GFP and the viral replicase. These data suggest that viral spread may be a consequence of the replication process. Observation point out that expression of proteins from the mp sgp is temporary regulated, and degradation of the proteins occurs rapidly or more slowly, depending on protein stability. It is suggested that the MP contains an external degradation signal that contributes to rapid degradation of the protein even if expressed from the constitutive cp sgp. Experiments conducted to determine whether the degradation of GFP and MP:GFP was regulated at the protein or RNA level, indicated that regulation was at the protein level. RNA accumulation in infected protoplast was not always in correlation with protein accumulation, indicating that other mechanisms together with RNA production determine the final intensity and stability of the fluorescent proteins.
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