Academic literature on the topic 'RDF Saturation'
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Journal articles on the topic "RDF Saturation"
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Pandeline, Deborah A., Paul J. Cosentino, Edward H. Kalajian, and Mario F. Chavez. "Shear and Deformation Characteristics of Municipal Waste Combustor Bottom Ash for Highway Applications." Transportation Research Record: Journal of the Transportation Research Board 1577, no. 1 (January 1997): 101–8. http://dx.doi.org/10.3141/1577-13.
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Municipal waste combustor (MWC) bottom ash from mass-burn (MB) and refuse-derived-fuel (RDF) facilities was evaluated for potential use as highway fill material. MWC bottom ash exhibits acceptable shear and deformation characteristics for many highway applications. RDF ash contains a lower metals percentage than MB ash. The specific gravity of both ashes was found to be a function of metals content. Moisturedensity relationships and unconfined compressive strengths were found to be a function of compaction energy and moisture content. Allowing compacted ash to age increased its unconfined compressive strength. Stress-strain characteristics of both ashes are similar to those of sands. Cohesion exists possibly because of pozzolonic reactions in the bottom ash. The angle of internal friction increased with compacted density. Elastic moduli are a function of density and confining pressure. RDF ash was found to be twice as stiff as MB ash. California bearing ratio results greater than 100 indicated that MB ash could be utilized as road base, and values between 25 and 95 indicated that RDF would be acceptable for use in subgrade and subbase. Bearing ratio results were highly dependent on moisture conditions. Both ashes exhibit little to no swell and should not cause field problems during saturation.
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Zamora, Jonathan, Israel Betancourt, and José Alejandro García Hinojosa. "The Influence of Boron on Microstructural Evolution, Mechanical and Magnetic Behavior of Amorphous Fe91−x(Zr5-Nb4)Bx Melt-Spun Alloys." Metals 12, no. 6 (June 10, 2022): 994. http://dx.doi.org/10.3390/met12060994.
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In this work, we report a systematic study on the microstructure evolution of rapid solidified Fe91−xZr5Nb4Bx alloys (x = 10, 15, 20, 25, 30 at%) under melt-spinning conditions. Mechanical and magnetic properties are also evaluated. X-ray diffraction patterns indicate that the microstructure across the compositional series consists of an amorphous matrix with partial crystallization when boron concentration is increased. These features were identified by transmission electron microscopy (TEM). The radial distribution function (RDF) affords to resolve the nearest-neighbor configuration. The tensile and microhardness properties were measured to correlate the microstructural evolution with boron content. On the other hand, the magnetic properties of these alloy series were determined by vibrating sample magnetometry (VSM); the saturation magnetization and Curie temperature showed an increasing tendency when increasing the boron content, reaching values up to 110 Am2kg−1 and 465 K, respectively. In addition to the aforementioned, the coercive field remained constant. All these magnetic properties were correlated with the microstructure features observed by XRD, RDF and TEM.
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Krishtal, S., M. Kiselev, Y. Puhovski, T. Kerdcharoen, S. Hannongbua, and K. Heinzinger. "Study of the Hydrogen Bond Network in sub-and supercritical Water by Molecular Dynamics Simulations." Zeitschrift für Naturforschung A 56, no. 8 (August 1, 2001): 579–84. http://dx.doi.org/10.1515/zna-2001-0807.
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Abstract For 12 points along the tangent to the saturation curve at the critical point the temperature dependencies of the heights of the first maximum in the 0 -0 RDF, the average number of hydrogen bonds, and the self-diffusion coefficients have been calculated from MD simulations. The curves of these three properties show an inflection near the critical point. To improve the understanding of these changes in going from subcritical to supercritical water the librational spectra and the change in the fractions of water molecules with a given number of hydrogen bonds as a function of temperature have been derived from the simulations, additionally.
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Choi, Yejoo, Jinwoong Lee, Jaehyuk Lim, Seungjun Moon, and Changhwan Shin. "Impact of Process-Induced Variations on Negative Capacitance Junctionless Nanowire FET." Electronics 10, no. 16 (August 7, 2021): 1899. http://dx.doi.org/10.3390/electronics10161899.
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In this study, the impact of the negative capacitance (NC) effect on process-induced variations, such as work function variation (WFV), random dopant fluctuation (RDF), and line edge roughness (LER), was investigated and compared to those of the baseline junctionless nanowire FET (JL-NWFET) in both linear (Vds = 0.05 V) and saturation (Vds = 0.5 V) modes. Sentaurus TCAD and MATLAB were used for the simulation of the baseline JL-NWFET and negative capacitance JL-NWFET (NC-JL-NWFET). Owing to the NC effect, the NC-JL-NWFET showed less variation in terms of device performance, such as σ[Vt], σ[SS], σ[Ion/Ioff], σ[Vt]/µ[Vt], σ[SS]/µ[SS], and σ[Ion/Ioff]/µ[Ion/Ioff], and enhanced device performance, which implies that the NC effect can successfully control the variation-induced degradation.
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Yadav, O. S., Sanjay Swami, and T. V. Sowjanya. "Impact of biochar on nutrient uptake by tomato, residual soil properties and acidity indices in acid Inceptisol of Meghalaya." Journal of Environmental Biology 41, no. 6 (November 15, 2020): 1761–73. http://dx.doi.org/10.22438/jeb/41/6/si-276.
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Aim: To investigate the impact of biochar as component of integrated nutrient management on nutrient uptake by tomato in acid soil of Meghalaya, North East India. Methodology: A field experiment was conducted at research farm of SNRM, College of Post Graduate Studies in Agricultural Sciences (CPGS-AS), Central Agricultural University (CAU-I), Umiam during rabi 2017-18 taking tomato, cv. Megha Tomato-2 as test crop. Sixteen treatment combinations of recommended closes of fertilizers, biochar and vermicompost? were tested in RBD with three replications.? Results: The experimental results revealed that combined application of biochar, fertilizers and vermicompost increased the uptake and availableof N, P, K, Fe, Zn, Mn and Cu over graded doses of biochar + fertilizers, biochar alone and control. Electrical conductivity, bulk density, exchangeable acidity, exchangeable aluminium and acid saturation followed the same trend.? Interpretation: The 100% RDF + biochar 4 t ha-1 + vermicompost @ 2.5 t ha-1 is the most appropriate combination for increasing tomato productivity and improving soil health of acidic soil in Meghalaya.
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Cao, Xinfang, and Shuo Lu. "Molecular Dynamics Simulation of the Effects of Different Initial Water Content on Methane Hydrate Decomposition." Scientific and Social Research 5, no. 12 (December 27, 2023): 60–65. http://dx.doi.org/10.26689/ssr.v5i11.5837.
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Gas hydrate is mainly distributed in deep sea-floor sediments and permafrost regions. The water content of these sediments varies with the type of reservoir and affects the rate of hydrate decomposition. In this work, the decomposition process of methane hydrate under four different initial water contents was investigated by molecular dynamics simulation. The results were analyzed by the system conformation, radial distribution function (RDF), and mean square displacement (MSD), which revealed the microscopic mechanism of the effect of the initial water content on the decomposition rate of hydrate. The results demonstrate that the hydrate decomposition starts from the boundary to the middle, and the cage structure is destroyed layer by layer. Methane molecules continue to escape from the hydrate cages as the hydrate decomposes, and subsequent decomposition of the hydrate is inhibited when its solubility in water reaches saturation. The higher the initial water content is, the faster the decomposition rate of hydrate is. The movement distance of methane gas is affected by the initial water content. The higher the initial water content, the smaller the MSD of methane molecules.
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MAJID, DEWAN S. A., EDWARD W. INSCHO, and L. GABRIEL NAVAR. "P2 Purinoceptor Saturation by Adenosine Triphosphate Impairs Renal Autoregulation in Dogs." Journal of the American Society of Nephrology 10, no. 3 (March 1999): 492–98. http://dx.doi.org/10.1681/asn.v103492.
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Abstract. Recent studies have suggested a role for P2 purinoceptors on vascular smooth muscle cells in the mechanism of renal autoregulation. Experiments were performed in anesthetized dogs (n = 9) to examine renal blood flow (RBF) auto-regulatory efficiency before and after saturation of P2 purinoceptors with acute intra-arterial administration of ATP (1 mg/kg per min). Dogs were pretreated with the nitric oxide synthase inhibitor nitro-L-arginine (NLA) (50 μg/kg per min), to avoid endothelial P2 receptor-mediated effects on nitric oxide release caused by the intra-arterial ATP infusions. NLA treatment decreased RBF (5.3 ± 0.3 to 3.6 ± 0.2 ml/min per g) and sodium excretion (3.6 ± 0.4 to 0.9 ± 0.2 ml/min per g) without producing significant changes in GFR (0.92 ± 0.04 to 0.90 ± 0.06 ml/min per g) or RBF autoregulatory efficiency. ATP administration to NLA-treated dogs resulted in further decreases in RBF (2.8 ± 0.2 ml/min per g), GFR (0.58 ± 0.05 ml/min per g), and sodium excretion (0.6 ± 0.2 μmol/min per g). In addition, there was marked impairment of RBF autoregulatory efficiency during ATP infusion. The slopes of the arterial pressure-blood flow relationships at renal arterial pressures of >75 mmHg were significantly altered, from 0.003 ± 0.001 to 0.2 ± 0.002 ml/min per g per mmHg. Discontinuation of ATP infusion restored RBF autoregulatory efficiency. Norepinephrine (5 μg/kg per min) administration in these NLA-treated dogs decreased RBF (2.5 ± 0.3 ml/min per g; n = 4) to a similar extent, compared with ATP, but did not impair RBF autoregulation. These results support the hypothesis that P2 purinoceptors may be involved in mediating autoregulatory adjustments in renal vascular resistance.
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Deng, Hua, Renqiang Wang, Jingdong Li, Dawei Chen, Jianming Sun, Yue Zhao, and Jiabao Du. "RBF Neural Network Control for USV with Input Saturation." MATEC Web of Conferences 214 (2018): 03002. http://dx.doi.org/10.1051/matecconf/201821403002.
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Intelligent control for USV with input saturation based on RBF network was proposed. Firstly, sliding surfaces with integral were designed on the basis of the sliding mode variable structure control technology. Secondly, RBF network was applied to approximate compensate the input saturation of system, and which was optimized by Genetic Algorithms. Finally, the control algorithm for USV was deduced by backstepping method with Lyapunov theory on the basis of sliding mode control. Relevant simulations show the control method is available for USV motion control.
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Lian, Xiaobin, Jiafu Liu, Chuang Wang, Tiger Yuan, and Naigang Cui. "RBF network based adaptive sliding mode control for solar sails." Aircraft Engineering and Aerospace Technology 90, no. 8 (November 5, 2018): 1180–91. http://dx.doi.org/10.1108/aeat-04-2017-0112.
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Purpose The purpose of this paper is to resolve complex nonlinear dynamical problems of the pitching axis of solar sail in body coordinate system compared with inertial coordinate system. And saturation condition of controlled torque of vane in the orbit with big eccentricity ration, uncertainty and external disturbance under complex space background are considered. Design/methodology/approach The pitch dynamics of the sailcraft in the prescribed elliptic earth orbits is established considering the torques by the control vanes, gravity gradient and offset between the center-of-mass (cm) and center-of-pressure (cp). The maximal torques afforded by the control vanes are numerically determined for the sailcraft at any position with any pitch angle, which will be used as the restriction of the attitude control torques. The finite/infinite time adaptive sliding mode saturation controller and Bang–Bang–Radial Basis Function (RBF) controller are designed for the sailcraft with restricted attitude control torques. The model uncertainty and the input error (the error between real input and ideal control law input) are solved using the RBF network. Findings The finite true anomaly adaptive sliding mode saturation controller performed better than the other two controllers by comparing the numerical results in the paper. The control torque saturation, the model uncertainty and the external disturbance were also effectively solved using the infinite and finite time adaptive sliding mode saturation controllers by analyzing the numerical simulations. The stabilization of the pitch motion was accomplished within half orbit period. Practical implications The complex accurate dynamics can be approximated using the RBF network. The controllers can be applied to stabilization of spacecraft attitude dynamics with uncertainties in complex space environment. Originality/value Advanced control method is used in this paper; saturation of controlled torque of vane is resolved when the orbit with big eccentricity ration is considered and uncertainty and external disturbance under complex space background are settled. Moreover, complex and accurate nonlinear dynamical model of pitching axis of solar sail in body coordinate system compared with inertial coordinate system is provided.
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Sarrafan, Neda, and Khoshnam Shojaei. "High-Gain Observer-Based Neural Adaptive Feedback Linearizing Control of a Team of Wheeled Mobile Robots." Robotica 38, no. 1 (April 11, 2019): 69–87. http://dx.doi.org/10.1017/s026357471900047x.
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SummaryThis paper addresses the neural network (NN) output feedback formation tracking control of nonholonomic wheeled mobile robots (WMRs) with limited voltage input. A desired formation is achieved based on the leader–follower strategy utilizing hyperbolic tangent saturation functions to reduce the risk of actuator saturation. The controller is developed by incorporating the high-gain observer and radial basis function (RBF) NNs using the inverse dynamics control technique. The high-gain observer is introduced to estimate velocities of the followers. The RBF NN preserves the robustness of the proposed controller against uncertain nonlinearities. The adaptive laws are also combined by a robust control term to estimate the weights of RBF NN, approximation errors, and bounds of unknown time-variant environmental disturbances. A Lyapunov-based stability analysis proves that all signals of the closed-loop system are bounded, and tracking errors are uniformly ultimately bounded. Finally, some simulations are carried out to show the effectiveness of the proposed controller for a number of WMRs.
Dissertations / Theses on the topic "RDF Saturation"
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Bouhamoum, Redouane. "Découverte automatique de schéma pour les données irrégulières et massives." Electronic Thesis or Diss., université Paris-Saclay, 2021. http://www.theses.fr/2021UPASG081.
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Le web des données est un espace dans lequel de nombreuses sources sont publiées et interconnectées, et qui repose sur les technologies du web sémantique. Cet espace offre des possibilités d'utilisation sans précédent, cependant, l'exploitation pertinente des sources qu'il contient est rendue difficile par l'absence de schéma décrivant leur contenu. Des approches de découverte automatique de schéma ont été proposées, mais si elles produisent des schémas de bonne qualité, leur complexité limite leur utilisation pour des sources de données massives. Dans notre travail, nous nous intéressons au problème du passage à l'échelle de la découverte de schéma à partir de sources de données RDF massives dont le schéma est incomplet ou absent. Nous nous intéressons également à l'incrémentalité de ces approches et à la prise en compte de connaissances implicites fournies par une source de données.Notre première contribution consiste en une approche scalable de découverte de schéma qui permet l'extraction des classes décrivant le contenu d'une source de données RDF massive. Pour cela, nous avons d'abord proposé d'extraire une représentation condensée d'une source de données RDF qui servira en entrée du processus de découverte de schéma afin d'en améliorer les performances.Cette représentation est un ensemble de patterns qui correspondent à des combinaisons de propriétés décrivant les entités du jeu de données.Nous avons ensuite proposé une approche scalable de découverte de schéma fondée sur un algorithme de clustering distribué qui forme des groupes d'entités structurellement similaires représentant les classes du schéma.Notre deuxième contribution a pour but de maintenir le schéma extrait cohérent avec les changements survenant au niveau des sources RDF, ces dernières étant en constante évolution. Nous proposons pour cela une approche incrémentale de découverte de schéma qui modifie l'ensemble des classes extraites en propageant dans ces dernières les changements survenus dans les sources.Enfin, dans la troisième contribution de notre travail, nous adaptons notre approche de découverte de schéma afin qu'elle prenne en compte toute la sémantique portée par la source de données, qui est représentée par les triplets explicitement déclarés, mais également tous ceux qui peuvent en être déduits par inférence. Nous proposons une extension permettant de prendre en compte toutes les propriétés d'une entité lors de la découverte de schéma, qu'elles correspondent à des triplets explicites ou implicites, ce qui améliorera la qualité du schéma produitThe web of data is a huge global data space, relying on semantic web technologies, where a high number of sources are published and interlinked. This data space provides an unprecedented amount of knowledge available for novel applications, but the meaningful usage of its sources is often difficult due to the lack of schema describing the content of these data sources. Several automatic schema discovery approaches have been proposed, but while they provide good quality schemas, their use for massive data sources is a challenge as they rely on costly algorithms. In our work, we are interested in both the scalability and the incrementality of schema discovery approaches for RDF data sources where the schema is incomplete or missing.Furthermore, we extend schema discovery to take into account not only the explicit information provided by a data source, but also the implicit information which can be inferred.Our first contribution consists of a scalable schema discovery approach which extracts the classes describing the content of a massive RDF data source.We have proposed to extract a condensed representation of the source, which will be used as an input to the schema discovery process in order to improve its performances.This representation is a set of patterns, each one representing a combination of properties describing some entities in the dataset. We have also proposed a scalable schema discovery approach relying on a distributed clustering algorithm that forms groups of structurally similar entities representing the classes of the schema.Our second contribution aims at maintaining the generated schema consistent with the data source it describes, as this latter may evolve over time. We propose an incremental schema discovery approach that modifies the set of extracted classes by propagating the changes occurring at the source, in order to keep the schema consistent with its evolutions.Finally, the goal of our third contribution is to extend schema discovery to consider the whole semantics expressed by a data source, which is represented not only by the explicitly declared triples, but also by the ones which can be inferred through reasoning. We propose an extension allowing to take into account all the properties of an entity during schema discovery, represented either by explicit or by implicit triples, which will improve the quality of the generated schema
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Joo, Daniel. "EXPERIMENTS IN POOL BOILING HEAT TRANSFER AND NUCLEATIONDYNAMICS OF HIGH PRESSURE REFRIGERANTS." Master's thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3057.
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A high pressure pool boiling experiment of pressurized R134a is designed and built, utilizing thermochromatic liquid crystal techniques. Liquid crystals thermo-chromatography uses encapsulated liquid crystals that are sensitive to temperature. When exposed to hot temperatures the crystal reflect a blue/violet color, and when exposed to cooler temperatures it reflects a red/orange color. The color value or hue is proportional to its temperature. Using this technique this experiment is capable of studying the physics and thermodynamics of refrigerants under nucleate pool boiling. The main objective of this experiment was the design of the experimental setup. Various designs were tested and validated, of which all incorporated a pressure resistant chamber constructed out of aluminum and glass viewing ports. Design parameters such as the heating element thickness were verified using a transient FEA thermal model. This model, which was developed in ANSYS, verified that this design would be able to capture the thermal response of the thermochromatic liquid crystals. This analysis concluded that a negligible error of 0.02°C is expected due to transient effects. Difficulties were encountered during early stages of development; most notable were imaging limitations such as low camera frame-rates and poor resolution. Since a TLC technique was used to measure the temperature of the boiling surface, a camera system fast enough to capture the thermal response was needed. At bubble frequencies of 30 nucleations per second, it was necessary for the camera to have much higher frame rates. Through the use of two synchronized cameras, the surface temperature, position, size and shape of the bubbles were recorded simultaneously. Two camera systems were designed and tested. The first system consisted of a high speed CMOS camera capable of capturing 1,000 frames per second, and an RBG CCD color camera capable of 30 Frames per second. However, this system was limited the slow frame rate and low resolution of the RBG camera. The second system used two high resolution and fast shutter speed cameras, which were able to capture fast bubble nucleations. This method required the assumption that under constant operating conditions, the path of one bubble was identical to the next. This method was tested utilizing the high speed camera, and was shown that there was less than a .04% deviation from the path any bubble to that of the next. Detailed analysis of nucleating surface temperatures using thermochromatic liquid crystal technique and temporal-temperature response under various heat flux and at 813.6kPa (118Psia) and 882.5kPa (128Psia) was performed. It is seen that temperature distribution is quite varied in each case. At high pressures the size of nucleation site decreases, giving rise to an increase in the surface temperature. Bubble growth is also analyzed through the use of high speed cameras and compared to temperature distributions. Simultaneous temperature and bubble size measurements provided a correlation between bubble growth and heat transfer. Boiling parameters such as bubble frequency, bubble size, and contact area are also analyzed. From the surface temperature plots, the local and average heat transfer coefficients were calculated as a function of time and bubble dynamics.M.S.
Department of Mechanical, Materials and Aerospace Engineering;
Engineering and Computer Science
Mechanical Engineering
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Gomez, Carlos E. "Ecological and physiological constraints of deep-sea corals in a changing environment." Diss., Temple University Libraries, 2018. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/535228.
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BiologyPh.D.
Deep-water or cold-water corals are abundant and highly diverse, greatly increase habitat heterogeneity and species richness, thereby forming one of the most significant ecosystems in the deep sea. Despite this remote location, they are not removed from the different anthropogenic disturbances that commonly impact their shallow-water counterparts. The global decrease in seawater pH due to increases in atmospheric CO2 are changing the chemical properties of the seawater, decreasing the concentration of carbonate ions that are important elements for different physiological and ecological processes. Predictive models forecast a shoaling of the carbonate saturation in the water column due to OA, and suggest that cold-water corals are at high risk, since large areas of suitable habitat will experience suboptimal conditions by the end of the century. The main objective of this study was to explore the fate of the deep-water coral community in time of environmental change. To better understand the impact of climate change this study focused in two of the most important elements of deep-sea coral habitat, the reef forming coral Lophelia pertusa and the octocoral community, particularly the gorgonian Callogorgia delta. By means of controlled experiments, I examined the effects of long- and short-term exposures to seawater simulating future scenarios of ocean acidification on calcification and feeding efficiency. Finally In order to understand how the environment influences the community assembly, and ultimately how species cope with particular ecological filters, I integrated different aspects of biology such functional diversity and ecology into a more evolutionary context in the face of changing environment. My results suggest that I) deep-water corals responds negatively to future OA by lowering the calcification rates, II) not all individuals respond in the same way to OA with high intra-specific variability providing a potential for adaptation in the long-term III) there is a disruption in the balance between accretion and dissolution that in the long term can shift from net accretion to net dissolution, and IV) there is an evolutionary implication for certain morphological features in the coral community that can give an advantage under stresfull conditions. Nevertheless, the suboptimal conditions that deep-water corals will experience by the end of the century could potentially threaten their persistence, with potentially negative consequences for the future stability of this already fragile ecosystem.
Temple University--Theses
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China, Chaitali. "MAGNETIC PROPERTIES OF SPUTTER DEPOSITED FE-BASED AMORPHOUS THIN FILMS FOR RESONATOR APPLICATION." Master's thesis, University of Central Florida, 2006. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/3377.
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In this study we investigate the magnetic properties of Fe-based amorphous thin films. Fe1-x-y-zBxSiyCz, Fe80-xNixB20, Fe80-xMnxB20, and Fe73-xMnxB27 films were deposited on silicon and glass substrates in a DC and RF magnetron sputtering system. Inductive magnetic measurements were performed to investigate the magnetic properties, including induced anisotropy and magnetostriction, of the as-deposited and annealed films using an M-H Looper. The chemical composition of the films was characterized using secondary ion mass spectroscopy (SIMS). The physical thickness of the films was determined by use of a stylus profilometer. The M-H Looper studies indicated that the induced anisotropy (Hk) depends strongly on the nickel concentration as well as on the annealing conditions, specifically the time and temperature of the annealing process. For the same metalloid concentration, the induced anisotropy has a maximum as a function of Ni. For the same nickel concentration and annealing time, it was found that the value of Hk decreases with the increase in annealing temperature. For each composition studied, low temperature long time annealing showed a higher value of Hk compared to high temperature short time annealing. From the magnetostriction values of Fe80-xNixB20 alloys, it was found that the sputter deposited films show similar trend but differ in magnitude when compared with ribbon samples. The magnetostriction of annealed thin films is found to be representative of ribbon samples. A potential composition modification to improve the strength of the field induced anisotropy is the addition of low levels of Mn.M.S.M.S.E.
Department of Mechanical, Materials and Aerospace Engineering;
Engineering and Computer Science
Materials Science and Engineering
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Jeffery, Samantha. "In-Plant and Distribution System Corrosion Control for Reverse Osmosis, Nanofiltration, and Anion Exchange Process Blends." Master's thesis, University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/5951.
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The integration of advanced technologies into existing water treatment facilities (WTFs) can improve and enhance water quality; however, these same modifications or improvements may adversely affect finished water provided to the consumer by public water systems (PWSs) that embrace these advanced technologies. Process modification or improvements may unintentionally impact compliance with the provisions of the United States Environmental Protection Agency's (USEPA's) Safe Drinking Water Act (SDWA). This is especially true with respect to corrosion control, since minor changes in water quality can affect metal release. Changes in metal release can have a direct impact on a water purveyor's compliance with the SDWA's Lead and Copper Rule (LCR).
In 2010, the Town of Jupiter (Town) decommissioned its ageing lime softening (LS) plant and integrated a nanofiltration (NF) plant into their WTF. The removal of the LS process subsequently decreased the pH in the existing reverse osmosis (RO) clearwell, leaving only RO permeate and anion exchange (AX) effluent to blend. The Town believed that the RO-AX blend was corrosive in nature and that blending with NF permeate would alleviate their concern. Consequently, a portion of the NF permeate stream was to be split between the existing RO-AX clearwell and a newly constructed NF primary clearwell. The Town requested that the University of Central Florida (UCF) conduct research evaluating how to mitigate negative impacts that may result from changing water quality, should the Town place its AX into ready-reserve.
The research presented in this document was focused on the evaluation of corrosion control alternatives for the Town, and was segmented into two major components:
1. The first component of the research studied internal corrosion within the existing RO clearwell and appurtenances of the Town's WTF, should the Town place the AX process on standby. Research related to WTF in-plant corrosion control focused on blending NF and RO permeate, forming a new intermediate blend, and pH-adjusting the resulting mixture to reduce corrosion in the RO clearwell.
2. The second component was implemented with respect to the Town's potable water distribution system. The distribution system corrosion control research evaluated various phosphate-based corrosion inhibitors to determine their effectiveness in reducing mild steel, lead and copper release in order to maintain the Town's continual compliance with the LCR.
The primary objective of the in-plant corrosion control research was to determine the appropriate ratio of RO to NF permeate and the pH necessary to reduce corrosion in the RO clearwell. In this research, the Langelier saturation index (LSI) was the corrosion index used to evaluate the stability of RO:NF blends. Results indicated that a pH-adjusted blend consisting of 70% RO and 30% NF permeate at 8.8-8.9 pH units would produce an LSI of +0.1, theoretically protecting the RO clearwell from corrosion.
The primary objective of the distribution system corrosion control component of the research was to identify a corrosion control inhibitor that would further reduce lead and copper metal release observed in the Town's distribution system to below their respective action limits (ALs) as defined in the LCR. Six alternative inhibitors composed of various orthophosphate and polyphosphate (ortho:poly) ratios were evaluated sequentially using a corrosion control test apparatus. The apparatus was designed to house mild steel, lead and copper coupons used for weight loss analysis, as well as mild steel, lead solder and copper electrodes used for linear polarization analysis. One side of the apparatus, referred to as the “control condition,” was fed potable water that did not contain the corrosion inhibitor, while the other side of the corrosion apparatus, termed the “test condition,” was fed potable water that had been dosed with a corrosion inhibitor. Corrosion rate measurements were taken twice per weekday, and water quality was measured twice per week. Inhibitor evaluations were conducted over a span of 55 to 56 days, varying with each inhibitor. Coupons and electrodes were pre-corroded to simulate existing distribution system conditions. Water flow to the apparatus was controlled with an on/off timer to represent variations in the system and homes.
Inhibitor comparisons were made based on their effectiveness at reducing lead and copper release after chemical addition. Based on the results obtained from the assessment of corrosion inhibitors for distribution system corrosion control, it appears that Inhibitors 1 and 3 were more successful in reducing lead corrosion rates, and each of these inhibitors reduced copper corrosion rates. Also, it is recommended that consideration be given to use of a redundant single-loop duplicate test apparatus in lieu of a double rack corrosion control test apparatus in experiments where pre-corrosion phases are implemented. This recommendation is offered because statistically, the control versus test double loop may not provide relevance in data analysis. The use of the Wilcoxon signed ranks test comparing the initial pre-corroding phase to the inhibitor effectiveness phase has proven to be a more useful analytical method for corrosion studies.M.S.Env.E.
Masters
Civil, Environmental, and Construction Engineering
Engineering and Computer Science
Environmental Engineering
Book chapters on the topic "RDF Saturation"
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Farvardin, Mohammad Amin, Dario Colazzo, Khalid Belhajjame, and Carlo Sartiani. "Scalable Saturation of Streaming RDF Triples." In Transactions on Large-Scale Data- and Knowledge-Centered Systems XLIV, 1–40. Berlin, Heidelberg: Springer Berlin Heidelberg, 2020. http://dx.doi.org/10.1007/978-3-662-62271-1_1.
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Sinton, Jamie W. "Respiratory Distress Syndrome." In Advanced Anesthesia Review, edited by Alaa Abd-Elsayed, 655—C256.S10. Oxford University PressNew York, 2023. http://dx.doi.org/10.1093/med/9780197584521.003.0255.
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Abstract Respiratory distress syndrome (RDS) is a condition of the newborn in which lack of pulmonary surfactant predisposes to atelectasis, intrapulmonary shunting, hypoxemia, and hypoventilation. These problems lead to reopening or failed closure of the patent ductus arteriosus, bronchopulmonary dysplasia (BPD), and pulmonary hypertension. RDS is commonly found in premature infants as their surfactant production is inadequate or has yet to occur or infants of diabetic mothers whose lungs are often immature for their gestational age. In addition to anesthetic considerations for newborns, those with RDS will benefit from a lower oxygen saturation target; avoidance of cold, dry respiratory gas; and maintenance of continuous positive airway pressure throughout the perioperative period.
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Kumar, Pradeep, and Abhijit Bhowmick. "Device-to-Device (D2D) Communication for Advanced Wireless Communication." In Advances in Wireless Technologies and Telecommunication, 21–43. IGI Global, 2023. http://dx.doi.org/10.4018/978-1-6684-7000-8.ch002.
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In cellular networks, device-to-device (D2D) communication is a new paradigm. In this chapter, the end-to-end performance (outage, throughput, improvement in spectrum utilization, and energy efficiency) of a non-linear energy harvesting D2D network underlaying a cellular network will be studied under a channel quality constraint. A D2D node harvests energy from RF signal of cellular users (CU) and power transfer units (PTUs) and transmits its information in hybrid mode. Spectrum sensing, censoring of users, and energy harvesting are incorporated to make the study more realistic. Spectrum sensing provides information about the CU spectrum status, censoring technique eliminates the D2D users from the transmission process of those who have bad quality channels. Analytical expressions of an outage, throughput, improvement in spectrum utilization (ISU), and energy efficiency are provided. The impact of the interference threshold on CU, the censoring threshold, and the saturation level of the energy harvester on network performance parameters is addressed.
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Joshi, Neetu. "Graphene FET for Microwave and Terahertz Applications." In Nanoscale Field Effect Transistors: Emerging Applications, 89–112. BENTHAM SCIENCE PUBLISHERS, 2023. http://dx.doi.org/10.2174/9789815165647123010008.
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A graphene based FET can be used for a variety of applications. It can be utilized in the fascinating field of nano-scale device electronics or microwave and terahertz based guided wave components. In this chapter, a review of graphene field effect transistors has been presented in RF and bio-sensor circuits. It begins with an overview of the superior properties of graphene in graphene FETs, moving further to the characterization and fabrication challenges, and thereafter, their application in bioanalytical sensing and high frequency devices has been investigated. Graphene material has potential advantages in the form of low losses and power dissipation due to its high thermal, electrical conductivities and mobilities. It leads to better performance and efficiency relative to its silicon counterparts in various applications. It has some design and fabrication challenges owing to its high surface density and single atomic thickness. It also shows limitations in terms of bandgap variation, high fabrication costs and current saturation features.
Conference papers on the topic "RDF Saturation"
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Farvardin, Mohammad Amin, Dario Colazzo, Khalid Belhajjame, and Carlo Sartiani. "Streaming saturation for large RDF graphs with dynamic schema information." In the 17th ACM SIGPLAN International Symposium. New York, New York, USA: ACM Press, 2019. http://dx.doi.org/10.1145/3315507.3330201.
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Surdutovich, G., R. Vitlina, M. Oria, L. Marcassa, S. Zilio, and V. S. Bagnato. "Vortex forces in magneto-optical traps for cesium and sodium: justification for spatial structures." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/oam.1992.thgg4.
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In this communication we show that the existence of previously observed spatial structures—balls, rings, and rings with balls—in MOT experiments with Cs (Ref. 1) and Na (Ref. 2) can be explained from a single general viewpoint, through the use of vortex forces.1, 2 The theory uses the saturable aspect of the vortex forces that originates from shifted Gaussian laser beams in MOT experiments and the coordinate dependences of the vortex forces. Depending on the conditions of saturation, any of the above observed structures can be explained only with spontaneous radiative forces. High saturation regimes and moderate detunings provide conditions for the formation of rings with a central ball. Moderated saturation and larger detunings provide conditions for formation of rings without a central ball. We apply the present theory to the experiments of Ref. 1.
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Ganguly, Susmita, K. Rai Dastidar, and T. K. Rai Dastidar. "Charge transfer in helium in a laser field: effect of rotation on the plane of polarization." In International Laser Science Conference. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/ils.1986.thl41.
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In our earlier studies1,2 of laser-assisted He+ −He charge transfer collision, we chose the laser light to be linearly polarized along the beam trajectory. In this work we demonstrate the effect of varying the angle β between the beam trajectory and the polarization vector. As in Ref. 2, we consider the multiple-photon exchange with the laser field (typical bandwidth ~1 Å) until saturation. Typical results for charge transfer probability (P s ) after saturation are shown at two different β, together with P0, the field-free values. A significant dephasing occurs in the P s curve as the angle β is changed from 0° to 45°. The consequent change in cross section relative to the field-free case drops from −34% to ≲ 1%.
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Ding, Y. J., C. L. Guo, J. B. Khurgin, K. K. Law, and J. L. Merz. "Evidence for strong saturation of interface traps in multiple narrow slightly asymmetric coupled quantum wells." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/oam.1992.wb4.
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Based on our measurements of cw intensity-dependent photoluminescence (PL) excitation spectra of multiple narrow slightly asymmetric coupled quantum wells (ACQWs) at room temperature, strong saturation of interface traps has been observed similar to that reported in Ref. 1. Each ACQW consists of two GaAs QWs of thicknesses of 1.8 nm and 2.1 nm separated by a 3 nm Al0 4Ga0 6As barrier. As laser intensity increases, PL intensity initially increases at a rate higher than that for a square-law dependence and finally approaches that dependence. This phenomenon can be attributed to a dominant nonradiative recombination at the interface traps undergoing a strong saturation with weak radiative recombination of free carriers. Intensity-dependent trapping efficiency and the ratio of electron and hole nonradiative decay times, and the ratio of trapping and nonradiative recombination rates have been determined from the experiment.
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Ding, Yujie J., and Jacob B. Khurgin. "Degenerate Backward Optical Parametric Oscillators and Amplifiers: Conversion Efficiencies and Gain Saturation." In Nonlinear Optics: Materials, Fundamentals and Applications. Washington, D.C.: Optica Publishing Group, 1996. http://dx.doi.org/10.1364/nlo.1996.nme.18.
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Since quasi-phase matching (QPM) was proposed in Ref. [1], there have been many demonstrations [2] of achieving second-harmonic generation (SHG) based on QPM. Recently, due to rapid development of poled nonlinear materials such as LiNbO3, optical parametric oscillators (OPOs) and amplifiers (OPAs) have been intensively studied [3]. In these investigations, the thickness of each domain is usually much larger than the wavelengths of the parametric and pump wave based on QPM. Recently, GaAs/AlGaAs multilayers [4] and asymmetric coupled quantum-well domain structures [5] were used to achieve SHG. Most recently, we proposed transversely-pumped counter-propagating OPOs and OPAs (TPCOPOs and TPCOPAs) based on semiconductor structures [6], which is the reverse process of surface-emitting sum-frequency generation. In this configuration, the parametric waves counter-propagate in a waveguide along the epitaxial layer plane while pump waves propagate along the surface normal. Oscillation can occur without an external feedback. Such a concept was first introduced for nondegenerate backward OPO based on conventional phase-matching [7]. Recently, we investigated the conversion efficiency vs. the pump intensity in this configuration, however, based on QPM [8]. Here, we present our result of the first study of the degenerate backward optical parametric oscillators (DBOPOs) and optical parametric amplifiers (DBOPAs) in a waveguide based on QPM. DBOPO can occur without an external feedback. This is fundamentally different from conventional OPO. A second-order nonlinear optical material consists of many domains in which the adjacent domains have the opposite signs of second-order susceptibilities, but the same magnitude [χ0(2)], see Fig. 1. The spatial period of the domains is l0 = λ0/n0, where n0 is the effective refractive index the domains at the wavelength λ0. A pump wave at the wavelength in vacuum λ0ω = λ0 propagates along the positive z axis and is reflected by a mirror attached to the right-side facet with the reflectivity R2ω. These two counter-propagating pump waves interact with the nonlinear medium. As a result, DBOPOs can occur in the nonlinear medium, i.e. forward and backward parametric waves are generated and propagate along the positive and negative z axes, respectively, see Fig. 1(a).
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Kimble, H. J., and R. J. Cook. "Monitoring quantum transitions in a three-level atom." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1985. http://dx.doi.org/10.1364/oam.1985.fn1.
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In a recent publication1 the question of the possibility of observing directly the quantum jumps associated with the excitation and deexcitation of an atomic electron in a three-level transition was considered. While the analysis of Ref. 1 reveals the manner in which the fluorescence from a strong transition of a lifetime T1 is modulated by the absorption and emission processes of a weak transition of lifetime T2 (T1 ≪ T2), it was restricted to the case of incoherent excitation of the two transitions. The purpose of the present work is to reconsider this problem for monochromatic excitation in which a variety of coherent effects come into play. The analysis proceeds in a straightforward fashion in the Heisenberg representation to yield expressions for field and atomic correlation functions representing probabilities for the detection of successive photons from the same transition as well as for cross correlations of emission probabilities. In the limit of T1 ≪ T2, a coarse graining of time with respect to the strong transition produces expressions analogous to those presented in Ref. 1. The roles of Autler-Townes splitting, frequency detuning, and saturation of the weak transition are discussed.
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Yang, Ziming, Chuan Zhou, Jian Guo, Fei Han, Yue Sun, and Jiaji Gao. "Orbit-Attitude Cooperative Control for Micro-Nano Satellites with Input Saturation: Fault-tolerant Control Based on RBF Neural Network." In 2023 35th Chinese Control and Decision Conference (CCDC). IEEE, 2023. http://dx.doi.org/10.1109/ccdc58219.2023.10326700.
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Gorobets, V. A., V. O. Petukhov, S. Ya Tochitsky, and V. V. Churakov. "Field mechanism of simultaneous oscillation on several transitions in cw CO2 and CO lasers." In The European Conference on Lasers and Electro-Optics. Washington, D.C.: Optica Publishing Group, 1994. http://dx.doi.org/10.1364/cleo_europe.1994.ctuk88.
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The obtaining of the steady-state regime of simultaneous oscillation on several given lines in CO2 and CO lasers presents difficulties because of the competition between transitions. In Ref. 1, it is shown theoretically and experimentally that the steady-state multiwave regime in a TEA CO2 laser is possible at sufficiently high intensities of the light fields in the cavity. Due to the effect of “rotational or vibrational bottleneck" the competition between the transitions becomes considerably weaker. To weaken the competition, it is necessary to purposely create the conditions under which the field intensity in the cavity exceeds the saturation intensity of the CO2 molecule operating transitions, which is determined from the expression: Is = cπγ/τB, where c is light speed, γ is the collisional half width of the line, τ is the characteristic time of collisional relaxation, B is the integral Einstein coefficient for the centre of the vibrational-rotational transition. The field mechanism considered is applicable to multiwave oscillation at rotational transitions of both one band and various bands. In the last case, it is much easier to weaken the competition between the transitions. The effect of "vibrational bottleneck" comes into action at far lower saturation intensities, because it is determined by slower processes of vibrational exchange.
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Ya.I., Khanin, and I. V. Koryukin. "Combination Mode-Mode Coupling as an Instability Mechanism in a Dye Ring Laser." In Nonlinear Dynamics in Optical Systems. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/nldos.1992.mc19.
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The low-frequency time-dependent processes observed in the spectra of class A and class B lasers (according Arecchi [1]) can’t be explained using the rate equations. However, by introducing other nonlinear processes of mode coupling in addition to the laser medium saturation one gets a deeper insight into the nature of the multimode laser instability. There was a successful attempt in ref. [2] to take into account the influence of mode coupling on laser action via stimulated Brillouin scattering. However, it should be natural to seek for the reason of the nonlinear mode coupling in the laser medium itself. In the next high-order approximation of the dynamical theory of laser with adiabatically eliminated polarization, the combination mode-mode coupling (CMMC) due to the mode- induced inversion oscillations is taken into account [3-5].
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Wang, Yu, and Huichao Dai. "The Application of the Oxygen Saturation Level Prediction in Dam Lower Reaches Based on the Principle Component RBF Network Model." In 2010 International Conference on E-Product E-Service and E-Entertainment (ICEEE 2010). IEEE, 2010. http://dx.doi.org/10.1109/iceee.2010.5661525.
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