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Academic literature on the topic '62R20'

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Published: 1 June 2024

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Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Journal articles on the topic "62R20":

1

Urooj, Amena, and Zahid Asghar. "Evaluation of Test Statistics for Detection of Outliers and Shifts." Journal of Quantitative Methods 4, no. 2 (October 23, 2020): 54–75. http://dx.doi.org/10.29145/2020/jqm/040203.

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Existence of outliers and structural breaks having mutually unknown nature, in time series data, offer challenges to data analysts in model identification, estimation and validation. Detection of these outliers has been an important area of research in time series since long. To analyze the impact of these structural breaks and outliers on model identification, estimation and their inferential analysis, we use two data generating processes: MA(1) and ARMA(1,1). The performance of the test statistics for detecting additive outlier(AO), innovative outlier(IO), level shift(LS) and transient change(TC) is investigated using simulation strategy through power of a test, empirical level of significance, empirical critical values, misspecification frequencies and sampling distribution of estimators for the two models. The empirical critical values are found higher than the theoretical cut-off points, empirical power of the test statistics is not satisfactory for small sample size, large cut-off points and large model coefficient. We have explored confusion between LS, AO, TC and IO at different critical values(c) by varying sample size. We have also collected empirical evidence from time series data for Pakistan using 3-stage iterative procedure to detect multiple outliers and structural breaks. We find that neglecting shocks lead to wrong identification, biased estimation and excess kurtosis. JEL Classification Codes: C15, C18, C63, C32, C87, C51, C52, C82 AMS Classification Codes: 62, 65, 91, DI, 62-08, 62J20, 00A72, 91-08, 91-10, 91-11 62P20, 91B82, 91B84, 62M07, 62M09, 62M10, 62M15, 62M20
2

MANGKU, I. W. "L2-CONVERGENCE OF A NEAREST NEIGHBOR ESTIMATOR OF THE INTENSITY FUNCTION OF A CYCLIC POISSON PROCES." Journal of Mathematics and Its Applications 13, no. 2 (December 1, 2014): 49. http://dx.doi.org/10.29244/jmap.13.2.49-62.

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<p>Abstract. We consider the problem of estimating the intensity func- tion of a cyclic Poisson process. We suppose that only a single realization of the cyclic Poisson process is observed within a bounded 'window', and our aim is to estimate consistently the intensity function at a given point. A nearest neighbor estimator of the intensity function is proposed, and we show that our estimator is L2-consistent, as the window expands.<br />AMS 2010 subject classifications: 62E20, 62G05, 62G20.<br />Key words and phrases: cyclic Poisson process, cyclic intensity function, nonparametric estimation, nearest neighbor estimator, period, consis- tency, L2-convergence.</p>
3

Majumdar, Rajeshwari, and Suman Majumdar. "On Asymptotic Standard Normality of the Two Sample Pivot." Calcutta Statistical Association Bulletin 71, no. 1 (May 2019): 49–61. http://dx.doi.org/10.1177/0008068319853698.

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The asymptotic solution to the problem of comparing the means of two heteroscedastic populations, based on two random samples from the populations, hinges on the pivot underpinning the construction of the confidence interval and the test statistic being asymptotically standard normal, which is known to happen if the two samples are independent and the ratio of the sample sizes converges to a finite positive number. This restriction on the asymptotic behavior of the ratio of the sample sizes carries the risk of rendering the asymptotic justification of the finite sample approximation invalid. It turns out that neither the restriction on the asymptotic behavior of the ratio of the sample sizes nor the assumption of cross sample independence is necessary for the pivotal convergence in question to take place. If the joint distribution of the standardized sample means converges to a spherically symmetric distribution, then that distribution must be bivariate standard normal (which can happen without the assumption of cross sample independence), and the aforesaid pivotal convergence holds. AMS Classification: 62E20, 62G20
4

Kumar, R., and T. Kansal. "Rayleigh waves in transversely isotropic thermoelastic diffusive half-space." Canadian Journal of Physics 86, no. 9 (September 1, 2008): 1133–43. http://dx.doi.org/10.1139/p08-055.

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The present investigation is devoted to the study of the propagation of Rayleigh waves in a homogeneous, transversely isotropic, thermoelastic diffusive half-space subjected to stress-free, thermally insulated and (or) isothermal, and chemical potential boundary conditions, in the context of the theory of coupled thermoelastic diffusion. Secular equations for surface-wave propagation in the media being considered are derived. The surface-particle paths during the motion are found to be elliptical, but degenerate into straight lines in case where there is no phase difference between the horizontal and vertical components of the surface displacements. The phase velocity; attenuation coefficient; specific loss of energy; and the amplitudes of surface displacements, temperature change, and concentration are computed numerically and presented graphically to depict the anisotropy and diffusion effects. Some special cases of frequency equations are also deduced from the present investigation. PACS Nos.: 62.20.–x, 62.20.D–, 62.20.de, 62.20.dj, 62.20.dq, 62.30.+d, 66.10.C–, 66.10.cd, 66.10.cg, 66.30.–h
5

Na, Seok-Hyeon, Hyejin Jeon, Man-Hwan Oh, Yoo-Jeong Kim, Mingi Chu, Ill-Young Lee, and Je-Chul Lee. "Therapeutic Effects of Inhibitor of ompA Expression against Carbapenem-Resistant Acinetobacter baumannii Strains." International Journal of Molecular Sciences 22, no. 22 (November 12, 2021): 12257. http://dx.doi.org/10.3390/ijms222212257.

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The widespread of carbapenem-resistant Acinetobacter baumannii (CRAB) is of great concern in clinical settings worldwide. It is urgent to develop new therapeutic agents against this pathogen. This study aimed to evaluate the therapeutic potentials of compound 62520, which has been previously identified as an inhibitor of the ompA promoter activity of A. baumannii, against CRAB isolates, both in vitro and in vivo. Compound 62520 was found to inhibit the ompA expression and biofilm formation in A. baumannii ATCC 17978 at sub-inhibitory concentrations in a dose-dependent manner. These inhibitory properties were also observed in clinical CRAB isolates belonging to sequence type (ST) 191. Additionally, compound 62520 exhibited a bacteriostatic activity against clinical clonal complex (CC) 208 CRAB isolates, including ST191, and ESKAPE pathogens. This bacteriostatic activity was not different between STs of CRAB isolates. Bacterial clearance was observed in mice infected with bioimaging A. baumannii strain 24 h after treatment with compound 62520. Compound 62520 was shown to significantly increase the survival rates of both immunocompetent and neutropenic mice infected with A. baumannii ATCC 17978. This compound also increased the survival rates of mice infected with clinical CRAB isolate. These results suggest that compound 62520 is a promising scaffold to develop a novel therapeutic agent against CRAB infections.
6

Mekhtiche, Mohamed Amine, Zoubir Abdeslem Benselama, Mohamed Abdelkader Bencherif, Mohammed Zakariah, Mansour Alsulaiman, Ramdane Hedjar, Mohammed Faisal, Mohammed Algabri, and Khalid AlMuteb. "Visual Tracking in Unknown Environments Using Fuzzy Logic and Dead Reckoning." International Journal of Advanced Robotic Systems 13, no. 2 (January 2016): 53. http://dx.doi.org/10.5772/62120.

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Liang, Jicai, Ziyi Wang, Zhisen Li, Xiaofeng Wang, and Kaifeng Yu. "Fabrication of Nanostructured TiO2 Using a Solvothermal Reaction for Lithium-ion Batteries." Nanomaterials and Nanotechnology 6 (January 2016): 15. http://dx.doi.org/10.5772/62420.

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Salah, Numan, Sami Habib, Ameer Azam, M. Shahnawaze Ansari, and Waleed M. Al-Shawafi. "Formation of Mn-Doped SnO2 Nanoparticles Via the Microwave Technique: Structural, Optical and Electrical Properties." Nanomaterials and Nanotechnology 6 (January 2016): 17. http://dx.doi.org/10.5772/62520.

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Konstantinidis, A., N. Martini, V. Koukou, G. Fountos, N. Kalyvas, I. Valais, and C. Michail. "RAD_IQ: A free software for characterization of digital X-ray imaging devices based on the novel IEC 62220-1-1:2015 International Standard." Journal of Physics: Conference Series 2090, no. 1 (November 1, 2021): 012107. http://dx.doi.org/10.1088/1742-6596/2090/1/012107.

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Abstract Characterization of digital X-ray imaging devices is very important because it can be used to measure and compare the performance of detectors used in Diagnostic Radiology. This characterization is usually made through the calculation of Modulation Transfer Function (MTF), Noise Power Spectrum (NPS) and Detective Quantum Efficiency (DQE). These parameters, especially the DQE, are very important because they quantify the effect of spatial resolution, contrast and noise on Radiographic image quality (IQ). The IEC 62220-1-1:2015 International Standard provides comprehensive guidelines how to capture and analyze X-ray images to characterize digital X-ray detectors. A novel, fast and free MATLAB-based software was developed, named RAD_IQ, to calculate the Signal Transfer Property (STP), perform Noise Component Analysis (NCA), and calculate the parameters MTF, NPS & DQE of X-ray detectors based on the novel IEC 62220-1-1:2015 International Standard for General Radiography and IEC 62220-1-1:2007 for Digital Mammography. Our results were validated against well-established software products used for quantitative image analysis of digital X-ray detectors. The calculated parameters were within 5% difference compared to available software products. The conclusion of our study was that RAD_IQ can be easily used from Medical Physicists, Biomedical Engineers and researchers without any programming experience to characterize the performance of digital X-ray detectors used in Diagnostic Radiology.
10

Gupta, R. C., P. Varshney, Pravesh, M. Lal, D. Kumar, K. Singh, and A. S. Verma. "Mechanical stability parameters of chalcogenides and pnictides based optoelectronic materials." Chalcogenide Letters 20, no. 2 (February 23, 2023): 101–12. http://dx.doi.org/10.15251/cl.2023.202.101.

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A study of experimental data reveals that the bulk modulus of chalcogenides and pnictides based chalcopyrites (AIIBIVC2 V and AI BIIIC2 VI) can be explained by a simple scaling rule that rely only on the crystal ionicity, ionic charge product, and the melting temperature. PVV theory of crystal ionicity, temperature dependence of elasticity and product of ionic charge theory are taken into account for the study. Based on this result, a simple microhardnessbulk modulus relation is applied to evaluate the microhardness of the complex compounds; which correspond well with the experimental data and other published results. The proposed findings support in the modeling of emerging semiconductor materials and even understanding of their mechanical properties for optoelectronics, photovoltaic, electromagnetic (EM) screening, and spintronic applications. PACS: 62.20.-x; 62.20.Qp
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Journal articles Dissertations / Theses Books

Dissertations / Theses on the topic "62R20":

1

Romon, Gabriel. "Contributions to high-dimensional, infinite-dimensional and nonlinear statistics." Electronic Thesis or Diss., Institut polytechnique de Paris, 2023. http://www.theses.fr/2023IPPAG013.

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Trois problèmes sont abordés dans cette thèse: l'inférence en régression multi-tâche de grande dimension, les quantiles géométriques dans les espaces normés de dimension infinie, et les moyennes de Fréchet généralisées dans les arbres métriques. Premièrement, nous considérons un modèle de régression multi-tâche avec une hypothèse de sparsité sur les lignes de la matrice paramètre. L'estimation est faite en haute dimension avec l'estimateur Lasso multi-tâche. Afin de corriger le biais induit par la pénalité, nous introduisons un nouvel objet dépendant uniquement des données que nous appelons matrice d'interaction. Cet outil nous permet d'établir des résultats asymptotiques avec des lois limites normales ou chi². Il en découle des intervalles de confiance et des ellipsoïdes de confiance, qui sont valides dans des régimes de sparsité qui ne sont pas couverts par la littérature existante. Deuxièmement, nous étudions le quantile géométrique, qui généralise le quantile classique au cadre des espaces normés. Nous commençons par fournir de nouveaux résultats sur l'existence et l'unicité des quantiles géométriques. L'estimation est effectuée avec un M-estimateur approché et nous examinons ses propriétés asymptotiques en dimension infinie. Quand le quantile théorique n'est pas unique, nous utilisons la théorie de la convergence variationnelle pour obtenir des résultats asymptotiques sur les sous-suites dans la topologie faible. Quand le quantile théorique est unique, nous montrons que l'estimateur est consistant pour la topologie de la norme dans une large classe d'espaces de Banach, en particulier dans les espaces séparables et uniformément convexes. Dans les Hilbert séparables nous démontrons des représentations de Bahadur-Kiefer de l'estimateur, dont découle immédiatement la normalité asymptotique à la vitesse paramétrique. Finalement, nous considérons des mesures de tendance centrale pour des données vivant sur un réseau, qui est modélisé par un arbre métrique. Les paramètres de localisation que nous étudions sont appelés moyennes de Fréchet généralisées: elles sont obtenues en remplaçant le carré dans la définition de la moyenne de Fréchet par une fonction de perte convexe et croissante. Nous élaborons une notion de dérivée directionnelle dans l'arbre, ce qui nous aide à localiser et caractériser les minimiseurs. Nous examinons les propriétés statistiques du M-estimateur correspondant: nous étendons le concept de moyenne collante au contexte des arbres métriques, puis nous obtenons un théorème collant non-asymptotique et une loi des grands nombres collante. Pour la médiane de Fréchet, nous établissons des bornes de concentration non-asymptotiques et des théorèmes central limite collants
Three topics are explored in this thesis: inference in high-dimensional multi-task regression, geometric quantiles in infinite-dimensional Banach spaces and generalized Fréchet means in metric trees. First, we consider a multi-task regression model with a sparsity assumption on the rows of the unknown parameter matrix. Estimation is performed in the high-dimensional regime using the multi-task Lasso estimator. To correct for the bias induced by the penalty, we introduce a new data-driven object that we call the interaction matrix. This tool lets us develop normal and chi-square asymptotic distribution results, from which we obtain confidence intervals and confidence ellipsoids in sparsity regimes that are not covered by the existing literature. Second, we study the geometric quantile, which generalizes the classical univariate quantile to normed spaces. We begin by providing new results on the existence and uniqueness of geometric quantiles. Estimation is then conducted with an approximate M-estimator and we investigate its large-sample properties in infinite dimension. When the population quantile is not uniquely defined, we leverage the theory of variational convergence to obtain asymptotic statements on subsequences in the weak topology. When there is a unique population quantile, we show that the estimator is consistent in the norm topology for a wide range of Banach spaces including every separable uniformly convex space. In separable Hilbert spaces, we establish novel Bahadur-Kiefer representations of the estimator, from which asymptotic normality at the parametric rate follows. Lastly, we consider measures of central tendency for data that lives on a network, which is modeled by a metric tree. The location parameters that we study are called generalized Fréchet means: they obtained by relaxing the square in the definition of the Fréchet mean to an arbitrary convex nondecreasing loss. We develop a notion of directional derivative in the tree, which helps us locate and characterize the minimizers. We examine the statistical properties of the corresponding M-estimator: we extend the notion of stickiness to the setting of metrics trees, and we state a non-asymptotic sticky theorem, as well as a sticky law of large numbers. For the Fréchet median, we develop non-asymptotic concentration bounds and sticky central limit theorems
2

Bratt, Mark. "The synthesis of carbonates and related compounds from carbon dioxide." Thesis, University of Warwick, 2001. http://wrap.warwick.ac.uk/62120/.

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The manufacture of carbonates and carbamates is essential due to their wide range of applications from polymers in foams, elastomers and engineering plastics to agrochemicals. Since there is a high demand for both types of compound, there is a commercial justification for use of phosgene in their synthesis. However, phosgene is highly toxic in small quantities. The development of an alternative reagent is therefore most desirable. This thesis relates our attempts to overcome the problem of phosgene use by utilising C02. Chapter One highlights previous research concerning the synthesis of carbonates and their derivatives from CO2. Chapter Two details the development of the reaction of CO2 to form methanesulfonyl carbonates (RO(CO)OS02Me) and carbamates (R2N(CO)OS02Me), which are precursors of carbonates and carbamates respectively. Alcohols or amines are reacted with CO2 at atmospheric pressure in acetonitrile to generate carbonate and carbamate anions in situ. Reaction with methanesulfonic anhydride leads to the methanesulfonyl carbonates and carbamates which are observed spectroscopically but are not isolable. Chapter Three explains the successful conversion of methanesulfonyl carbonates and carbamates to carbonates and carbamates, as well as testing the scope of the reaction. Chapter Four demonstrates the transfer of the synthetic methodology to multifunctional compounds to generate dendritic carbamates and highlights the various approaches used to achieve this goal. Chapter Five is the experimental section.
3

Vijay, Arnesh. "Radio on visible light (RoVL) : an investigative study on the methods & techniques for the transmission of mobile signals through visible light channels." Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/62520/.

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Ever since the first mobile telephone call was made by a Motorola researcher in 1973, mobile technology has been growing rapidly to facilitate diverse ubiquitous services. Although cell based radio technology has proved beneficial for reliable long distance transmission, it is faced with challenges when deployed in an indoor environment. With the introduction of white LED - based communication entities at the start of the 21st century, radio and other technologies have become more interdependent, with the possibility for further expansion. Bearing in mind the sophistication offered, with the rapid developments witnessed in mobile telecommunications, this thesis presents an innovative alternative for cell phone connectivity in RF restricted or poor signal connectivity region. To address the research objective of offering uninterrupted signal connectivity in an indoor environment, the term Radio on Visible Light (RoVL) was introduced in this research. Furthermore, five major attributes influencing mobile signal transmission through visible light channels were identified and addressed. The bandwidth constraint offered by a white LED was tackled with an intelligent technique of frequency translation and mapping. In addition, an electronic predistorter was designed and implemented to address the nonlinearity in an LED. For efficient data manipulation, subcarrier continuous phase technique of modulation was introduced and hardware implemented for visible light communication, with a discussion on the LED number and arrangement for efficient illumination and data transmission. Despite the presence of significant research contributions in visible light technology, the study here is specifically focussed on integrating the GSM network with that of the optical wireless systems. The existing visible light entities provide service users with a one way broadband data transmission hub, unlike the dual channel support rendered by the RoVL device as presented in this research. The techniques proposed, backed up with interesting research observations and experimental results, clearly demonstrate the capability of supporting mobile communication through optical wireless channels. The methods proposed and techniques discussed shall lay foundation in supplementing the radio based mobile technology with optical wireless entities, opening new avenues for further research & development in this direction.
4

Kay, Christopher James. "Polyethylene block copolymers." Thesis, University of Warwick, 2014. http://wrap.warwick.ac.uk/62620/.

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Chapter 1 introduces the concept of polyethylene (PE) end-functionalisation as a route to block copolymers, reviews the different literature methods for their synthesis this way, and compares the advantages and disadvantages of each. Finally, an existing method which makes use of PE terminated with a styrene derivative is identified as having fewer disadvantages than most literature procedures. Further investigation of the mechanism is proposed. Chapter 2 focusses on the different types of so-called dormant state formed in Ziegler-Natta catalysed olefin polymerisations, and in particular on the dormancy occurring after styrene insertion. Copolymerisations of ethylene with styrene, allylbenzene and 4-phenyl-1-butene in the presence of hydrogen are undertaken, and evidence for the presence of a dormant state or simply competitive rates of hydrogenation vs ethylene insertion is discussed. Increasing styrene concentration beyond that used by Chung is found to yield PE capped at both chain ends with styrene. A new mechanism – Catalytic Hydride Initiated Polymerisation (CHIP) – is consistent with these new observations. Chapter 3 focusses on extending the application of the CHIP mechanism to the synthesis of new examples of end-functional PE. Copolymerisations of ethylene with α-methylstyrene and related monomers 1,3/1,4-diisopropenylbenzene, α-methylstyrene dimer and limonene in the presence of hydrogen are investigated, resulting in the successful synthesis of a range of PE examples initiated with each comonomer. The effects of hydrogen pressure and comonomer concentration are also discussed. The advantages of CHIP are discussed, and the synthesis of end-functionalised PE incorporating DIB is studied in detail. An α-methylstyrene like end group is present at the start of the PE chains. Chapter 4 describes the free-radical copolymerisation of the new functionalised PE with acrylate monomers. Observations are consistent with a new reversible termination mechanism similar to nitroxide mediated polymerisation. The products are characterised by NMR, GPC, DLS, TEM and DSC, and the evidence is found to be consistent with the presence of block copolymers. Chapter 5 details the experimental procedures used to carry out the work in this thesis.
5

Pickard, Stephen. "The purpose of stating the faith : an historical and systematic inquiry into the tradition of fundamental articles with special reference to Anglicanism." Thesis, Durham University, 1990. http://etheses.dur.ac.uk/6220/.

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Stating the faith in the form of fundamental articles has, historically, provided an important strategy by which the identity and continuity of the Church has been expressed. The issue underlying this ecclesiological context of fundamental articles concerns the truth of the one-in-Christ bond in Christianity. However discussion of fundamental articles of the faith has, from the Post-Reformation period, tended to occur as somewhat disconnected from wider concerns to do with the belief, discipleship and mission of the Church. One result is that important issues and motives implicit in the attempt to articulate the fundamental articles of Christianity remain undisclosed and undeveloped. By means of a multi-level approach - contemporary relevance (Part One), historical development (Part Two), case studies (Part Three) and systematic inquiry (Part Four) - this thesis develops an understanding of fundamental articles which shows how the theme is enmeshed within and contributes to the dynamic of Christian faith in the Church. The resources for this inquiry are drawn from an extensive, but hitherto largely unexamined treatment, of the theme of fundamental articles in Anglicanism. The Protestant tradition of speaking about fundamental articles of faith is found to offer an important medium through which the reality of being one-in-Christ can be identified, communicated and strengthened. In this way the tradition proves a valuable means for uncovering and examining the purpose(s) of stating the faith. The problematic role of fundamental articles in Anglican self- understanding reveals itself as an instance of a more general, controversial and unfinished task in theology to state the truth of God’s creating and redeeming love. The thesis thus draws attention to the significance of fundamental articles for expressing the nature and form of ecclesial faith and discipleship. A positive rationale emerges for a more intensive and discerning engagement with the fundamental articles tradition as a strategy by which theology can serve the mission of the Church.
6

Lawrence, Peter James. "Mesh generation by domain bisection." Thesis, University of Greenwich, 1994. http://gala.gre.ac.uk/6220/.

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The research reported in this dissertation was undertaken to investigate efficient computational methods of automatically generating three dimensional unstructured tetrahedral meshes. The work on two dimensional triangular unstructured grid generation by Lewis and Robinson [LeR76] is first examined, in which a recursive bisection technique of computational order nlog(n) was implemented. This technique is then extended to incorporate new methods of geometry input and the automatic handling of multiconnected regions. The method of two dimensional recursive mesh bisection is then further modified to incorporate an improved strategy for the selection of bisections. This enables an automatic nodal placement technique to be implemented in conjunction with the grid generator. The dissertation then investigates methods of generating triangular grids over parametric surfaces. This includes a new definition of surface Delaunay triangulation with the extension of grid improvement techniques to surfaces. Based on the assumption that all surface grids of objects form polyhedral domains, a three dimensional mesh generation technique is derived. This technique is a hybrid of recursive domain bisection coupled with a min-max heuristic triangulation algorithm. This is done to achieve a computationlly efficient and reliable algorithm coupled with a fast nodal placement technique. The algorithm generates three dimensional unstructured tetrahedral grids over polyhedral domains with multi-connected regions in an average computational order of less than nlog(n).
7

Pesare, Daniele. "Musitique: Informatica ed evoluzione del linguaggio musicale." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2013. http://amslaurea.unibo.it/6220/.

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Andreani, Lucia <1978&gt. "Development of an X-ray spectrometric system and feasibility tests of Silicon Drift Detector for medical and space applications." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6220/.

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The thesis work concerns X-ray spectrometry for both medical and space applications and is divided into two sections. The first section addresses an X-ray spectrometric system designed to study radiological beams and is devoted to the optimization of diagnostic procedures in medicine. A parametric semi-empirical model capable of efficiently reconstructing diagnostic X-ray spectra in 'middle power' computers was developed and tested. In addition, different silicon diode detectors were tested as real-time detectors in order to provide a real-time evaluation of the spectrum during diagnostic procedures. This project contributes to the field by presenting an improved simulation of a realistic X-ray beam emerging from a common X-ray tube with a complete and detailed spectrum that lends itself to further studies of added filtration, thus providing an optimized beam for different diagnostic applications in medicine. The second section describes the preliminary tests that have been carried out on the first version of an Application Specific Integrated Circuit (ASIC), integrated with large area position-sensitive Silicon Drift Detector (SDD) to be used on board future space missions. This technology has been developed for the ESA project: LOFT (Large Observatory for X-ray Timing), a new medium-class space mission that the European Space Agency has been assessing since February of 2011. The LOFT project was proposed as part of the Cosmic Vision Program (2015-2025).
9

Sheng, Lifei. "Three essays in operations management." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/62120.

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This thesis comprises three independent essays in operations management. The first essay explores a specific issue encountered by mobile gaming companies. The remaining two essays address the contracting problem in a supply chain setting. In the first essay, we study the phenomena of game companies offering to pay users in "virtual" benefits to take actions in-game that earn the game company revenue from third parties. Examples of such "incentivized actions" include paying users in "gold coins" to watch video advertising and speeding in-game progression in exchange for filling out a survey etc. We develop a dynamic optimization model that looks at the costs and benefits of offering incentivized actions to users as they progress in their engagement with the game. We find sufficient conditions for the optimality of a threshold strategy of offering incentivized actions to low-engagement users and then removing incentivized action to encourage real-money purchases once a player is sufficiently engaged. Our model also provides insights into what types of games can most benefit from offering incentivized actions. In the second essay, we propose what we call a generalized price-only contract, which is a dynamic generalization of the simple wholesale price-only contract. We derive some interesting properties of this contract and relate them to well-known issues such as double marginalization, relative power in a supply chain due to Stackelberg leadership, contract structure and commitment issues. In the third essay, we consider a supplier selling to a retailer with private inventory information over multiple periods. We focus on dynamic short-term contracts, where contracting takes place in every period. At the beginning of each period, with inventory or backlog kept privately by the retailer, the supplier offers a one-period contract and the retailer decides his order quantity in anticipation of uncertain customer demand. We cast the problem as a dynamic adverse-selection problem with Markovian dynamics. We show that the optimal short-term contract has a threshold structure, with possibly multiple thresholds. In certain cost regimes, the optimal contract entails a base-stock policy yet induces partial participation.
Business, Sauder School of
Operations and Logistics (OPLOG), Division of
Graduate
10

Hutchen, Jenna. "Snowshoe hare abundance and foraging behaviour in recently burned forests." Thesis, University of British Columbia, 2017. http://hdl.handle.net/2429/62420.

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A combination of climate change and decades of fire suppression has led to an increase in the size of wildfires in North American conifer forests. Large wildfires are more heterogeneous than smaller fires because of their landscape context and fire-weather that ignites them. Larger fires are patchier, and have more opportunities for good habitat, but they also produce large patches of open area where prey species are exposed to predation. For many mammal species, such as snowshoe hares (Lepus americanus) this patchiness means having to navigate quite different habitat patches while trying to locate adequate cover and food. The density of animals in burns of different sizes, and how individuals behave while foraging in those within-burn patches, is unknown for many species. This study addresses these knowledge gaps (fire size and within-burn patchiness) with two studies. First, I assessed densities of snowshoe hare in 9 wildfires that burned 13 years ago (3 each of small (~100 ha), medium (1000-5000 ha), and large (>10,000 ha)) and in mature forests in southern British Columbia to determine if fire size impacts hare density. I found that hares were highly variable in large burns but when they were present the densities were the highest of any sites. Hares were absent from small burns and most medium burns. Hares were commonly present in mature forests but at much lower densities than in large burns. Second, I assessed snowshoe hare foraging behaviour by measuring tortuosity, speed of movement, and amount of browse along winter foraging pathways in open and regenerating patches of the Okanagan Mountain Park fire (>25,000 ha) and surrounding mature forest. I found that hares moved the fastest and browsed the least in open patches, and moved slower and ate more in sapling patches. Hares did not change tortuosity. The data from these two studies show that fire size is an important predictor of snowshoe hare density and that hares change foraging behaviour to some degree based on the type of habitat they are in.
Irving K. Barber School of Arts and Sciences (Okanagan)
Biology, Department of (Okanagan)
Graduate
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Books on the topic "62R20":

1

Anuta, Michael J. Rotary clubs, Wisconsin and Michigan District 6220. Menominee, Mich: M.J. Anuta, 1993.

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Schmidt, Martha Mae. Church records of St. Paul United Church of Christ, 115 West B St., Belleville, IL, 62220, 1839-1939. Belleville, IL (P.O. Box 431, Belleville, 62222-0431): St. Clair County Genealogical Society, 1994.

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Adelman-Larsen, Niels Werner. Rock and Pop Venues. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-62320-3.

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Moritani, Toshio, and Aristides A. Capizzano, eds. Diffusion-Weighted MR Imaging of the Brain, Head and Neck, and Spine. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-62120-9.

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Mittelstedt, Christian. Rechenmethoden des Leichtbaus. Berlin, Heidelberg: Springer Berlin Heidelberg, 2021. http://dx.doi.org/10.1007/978-3-662-62720-4.

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Brodsky, Michael C. The Evolutionary Basis of Strabismus and Nystagmus in Children. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-62720-1.

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Franke, Dieter. Wälzlagerdiagnose an Maschinensätzen. Berlin, Heidelberg: Springer Berlin Heidelberg, 2022. http://dx.doi.org/10.1007/978-3-662-62620-7.

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Dominelli, Lena. Feminist Social Work Theory and Practice. Edited by Jo Campling. London: Macmillan Education UK, 2002. http://dx.doi.org/10.1007/978-0-230-62820-5.

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Hippe, Zdzisław S., Juliusz L. Kulikowski, and Teresa Mroczek, eds. Human-Computer Systems Interaction. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-62120-3.

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de Iaco Veris, Alessandro. Practical Astrodynamics. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-62220-0.

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Book chapters on the topic "62R20":

1

Gläser, Georg, Hyun-Sek Lukas Lee, Markus Olbrich, and Erich Barke. "Knowing Your AMS System’s Limits: System Acceptance Region Exploration by Using Automated Model Refinement and Accelerated Simulation." In Lecture Notes in Electrical Engineering, 1–14. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-62920-9_1.

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Aleksandrowicz, Gadi, Eli Arbel, Roderick Bloem, Timon D. ter Braak, Sergei Devadze, Goerschwin Fey, Maksim Jenihhin, et al. "Designing Reliable Cyber-Physical Systems." In Lecture Notes in Electrical Engineering, 15–38. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-62920-9_2.

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Herdt, Vladimir, Hoang M. Le, Daniel Große, and Rolf Drechsler. "On the Application of Formal Fault Localization to Automated RTL-to-TLM Fault Correspondence Analysis for Fast and Accurate VP-Based Error Effect Simulation: A Case Study." In Lecture Notes in Electrical Engineering, 39–57. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-62920-9_3.

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Rafiev, A., F. Xia, A. Iliasov, R. Gensh, A. Aalsaud, A. Romanovsky, and A. Yakovlev. "Error-Based Metric for Cross-Layer Cut Determination." In Lecture Notes in Electrical Engineering, 59–82. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-62920-9_4.

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Fürtig, Andreas, Sebastian Steinhorst, and Lars Hedrich. "Feature-Based State Space Coverage Metric for Analog Circuit Verification." In Lecture Notes in Electrical Engineering, 83–101. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-62920-9_5.

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Lu, Yue, and Tom J. Kazmierski. "Error-Free Near-Threshold Adiabatic CMOS Logic in the Presence of Process Variation." In Lecture Notes in Electrical Engineering, 103–14. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-62920-9_6.

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Dominelli, Lena. "Introduction." In Feminist Social Work Theory and Practice, 1–16. London: Macmillan Education UK, 2002. http://dx.doi.org/10.1007/978-0-230-62820-5_1.

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Dominelli, Lena. "Theorising Feminist Social Work Practice." In Feminist Social Work Theory and Practice, 17–40. London: Macmillan Education UK, 2002. http://dx.doi.org/10.1007/978-0-230-62820-5_2.

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Dominelli, Lena. "Contextualising Feminist Social Work Theory and Practice." In Feminist Social Work Theory and Practice, 41–63. London: Macmillan Education UK, 2002. http://dx.doi.org/10.1007/978-0-230-62820-5_3.

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Dominelli, Lena. "Redefining Professionalism." In Feminist Social Work Theory and Practice, 64–83. London: Macmillan Education UK, 2002. http://dx.doi.org/10.1007/978-0-230-62820-5_4.

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Conference papers on the topic "62R20":

1

"Concrete Pumping: A New World Record." In SP-173: Fifth CANMET/ACI International Conference on Superplasticizers and Other Chemical Admixtures in Concrete. American Concrete Institute, 1997. http://dx.doi.org/10.14359/6220.

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Caruntu, Dumitru I. "On Non-Axisymmetrical Transverse Vibrations of Circular Plates of Convex Parabolic Thickness Variation." In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-62020.

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This paper presents an approach for finding the solution of the partial differential equation of motion of the non-axisymmetrical transverse vibrations of axisymmetrical circular plates of convex parabolical thickness. This approach employed both the method of multiple scales and the factorization method for solving the governing partial differential equation. The solution has been assumed to be harmonic angular-dependent. Using the method of multiple scales, the partial differential equation has been reduced to two simpler partial differential equations which can be analytically solved and which represent two levels of approximation. Solving them, the solution resulted as first-order approximation of the exact solution. Using the factorization method, the first differential equation, homogeneous and consisting of fourth-order spatial-dependent and second-order time-dependent operators, led to a general solution in terms of hypergeometric functions. Along with given boundary conditions, the first differential equation and the second differential equation, which was nonhomogeneous, gave respectively so-called zero-order and first-order approximations of the natural frequencies and mode shapes. Any boundary conditions could be considered. The influence of Poisson’s ratio on the natural frequencies and mode shapes. Any boundary conditions could be considered. The influence of Poisson’s ratio on the natural frequencies and mode shapes could be further studied using the first-order approximations reported here. This approach can be extended to nonlinear, and/or forced vibrations.
3

Choudhury, Arnab, and Peter J. Hesketh. "Development of a Silicon Carbide Micro Four-Point Probe." In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-62220.

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The process development and fabrication of a cantilever-based micro four-point probe (MFPP) is presented. This device will allow for characterization of film resistance with micrometer-scaled resolution. The proble is designed for deployment on a commercial AFM. The cantilevers are made of amorphous silicon carbide (a-SiC) and the probe body using SU8. The probe consists of two sets of cantilevers, with integrated tips, on parallel planes 8.68 μm apart. This allows the probe to contact the surface in a square array and perform a van der Pauw type measurement. Studies to characterize, pattern and dope the a-SiC have been performed to utilize silicon carbide as both the cantilever structural material as well the conductive element in the sensor. The MFPP has been fabricated and some preliminary tests have been performed.
4

Lall, Pradeep, Nokibul Islam, and Jeff Suhling. "Reliability of BGA and CSP on Metal-Backed Printed Circuit Boards in Harsh Environments." In ASME 2004 International Mechanical Engineering Congress and Exposition. ASMEDC, 2004. http://dx.doi.org/10.1115/imece2004-62320.

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In this study, the effect of metal-backed boards on the interconnect reliability has been evaluated. Previous studies on electronic reliability for automotive environments have addressed the damage mechanics of solder joints in plastic ball-grid arrays on non-metal backed substrates [Lall et. al 2003, Syed et. al 1996, Evans et. al 1997, Mawer et. al 1999] and ceramic BGAs on non-metal backed substrates [Darveaux et. al 1992, 1995, 2000]. Delamination of PCBs from metal backing has also been investigated. Increased use of sensors and controls in automotive applications has resulted in significant emphasis on the deployment of electronics directly mounted on the engine and transmission. Increased shock, vibration, and higher temperatures necessitate the fundamental understanding of damage mechanisms which will be active in these environments. Electronics typical of office benign environments uses FR-4 printed circuit boards. Automotive application typically use high glass-transition temperature laminates such as FR4-06 glass/epoxy laminate material (Tg = 164.9°C). In application environments, metal-backing of printed circuits boards is being targeted for thermal dissipation, mechanical stability and interconnections reliability. The test vehicle is a metal backed FR4-06 laminate. The printed circuit board has an aluminum metal backing, attached with pressure sensitive adhesive (PSA). Component architectures tested include – plastic ball grid array devices, C2BGA devices, QFN, and discrete resistors. Reliability of the component architectures has been evaluated for HASL. Crack propagation and intermetallic thickness data has been acquired as a function of cycle count. Reliability data has been acquired on all these architectures. Material constitutive behavior of PSA has been measured using uni-axial test samples. The measured constitutive behavior has been incorporated into non-linear finite element simulations. Predictive models have been developed for the dominant failure mechanisms for all the component architectures tested.
5

Allameh, Seyed, Sharon Sarowa, and Miriam Kannan. "Algae-Based Biodiesel for Household Applications." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-62220.

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This paper presents the preliminary results of a research and developmental work on biodiesel production. An algae-based biofuel extraction system was developed for household applications. It consists of three modules: algae growth media preparation, biofuel-bearing algae growth chamber, and biodiesel extraction system. The details of the design and fabrication of these systems will be discussed. Further, the results of experiments on the selection of algae specimens and the influence of environmental variables on the growth process will be elucidated.
6

Kazmer, David O., Stephen P. Johnston, Mary E. Moriarty, and Christopher Santeufemio. "Passive Multi-Scale Alignment." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-62320.

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Methods are presented for self-alignment and assembly of objects with micron and nanometer-level features. The approach is a combination of kinematic coupling and elastic averaging in which mating alignment features spanning multiple length scales are successively brought into contact. When the objects are pressed together, the larger alignment features cause necessary deformation to ensure adequate alignment at the smaller length scales. Analytical and numerical modeling indicate that the largest alignment features can be designed to generally resolve global systematic errors while the smaller alignment features can correct local errors to achieve sub-micron alignment. Physical realization with ion beam etching, deposition, and thermal imprint lithography are also discussed.
7

Lin, Wamei, Jinliang Yuan, and Bengt Sunde´n. "Performance Analysis of a Countercurrent Flow Heat Exchanger Placed on the Truck Compartment Roof." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-62520.

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Due to the increasing power requirement and the limited available space in vehicles, placing the heat exchanger at the roof or the underbody of vehicles might increase the possibility to handle the cooling requirement. A new configuration of the heat exchanger has to be developed to accommodate with the position change. In this paper, a countercurrent heat exchanger is developed for position on the roof of the vehicle compartment. In order to find an appropriate configuration of fins with high thermal performance on the air side, the CFD (computational fluid dynamics) approach is applied for a comparative study among louver fin, wavy fin, and pin fin by using ANSYS FLUENT software. It is found that the louver fin has high thermal performance and low pressure drop. Thus, the louver fin is chosen to be the configuration of the countercurrent heat exchanger, which presents higher heat transfer coefficient than a cross flow heat exchanger. For a specific case, the overall size and the air pumping power of the countercurrent flow heat exchanger is lower than that one for a cross flow heat exchanger. Several suggestions and recommendations are highlighted.
8

Nishida, Ryuiti, Ying Yu, Yuqiu Yang, and Hiroyuki Hamada. "Notched Strength and Fractures Behavior of Chopped Glass Mat Reinforced Unsaturated Plastics." In ASME 2011 International Mechanical Engineering Congress and Exposition. ASMEDC, 2011. http://dx.doi.org/10.1115/imece2011-62820.

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Glass chopped fiber mats have been used as traditional reinforcements for fiber reinforced plastics. However, the literature is found limited even it has a long history. However short fiber mats is considered to be suitable reinforcement configuration for natural fiber or filled composites because the natural fiber is inherently short fiber. Various fiber textile technologies are available to be used to fabricate the fiber mats structure, for example needle punching process. Therefore the relation between different textile manufacturing techniques (the fiber mat structure) and the composites properties is considered necessary to be should be fully understood. Chopped glass mat reinforced composite was used as experimental materials and the fracture behavior of the specimens with drill-hole was investigated. Acoustic emission (AE) measurement was carried out by using Dual AE measurement system with both 140 KHz and 1 MHz sensors to understand the fiber and matrix fracture behaviors simultaneously. Also the characteristic distance was calculated experimentally and was compared theoretically with the values obtained from finite element stress analysis. It is found that the notched strength decrease by drilling a hole in the center. While regarding to the effect of w/d ratio i.e. the ratio of width to the diameter of the drill-hole, w/d of 3 specimens seems to have relative higher notched strength as compared to 2 or 5 w/d specimens. During the tensile test AE signals which detected by both 140 kHz and 1MHz are found to be generated almost at the same time. Additionally, the white area before the final broken seems to relative to the characteristic distance calculated by finite element stress analysis.
9

Harrouz, Jean Paul, Kamel Ghali, and Nesreen Ghaddar. "A Passive Ventilation and Air Conditioning System for an Office Space In Hot Climate." In ASME 2021 Heat Transfer Summer Conference collocated with the ASME 2021 15th International Conference on Energy Sustainability. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/ht2021-62520.

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Abstract Office spaces are characterized by strict constraints of thermal comfort and indoor air quality (IAQ) levels crucial for the occupants’ wellbeing and decision-making abilities. For these reasons, office spaces have large cooling loads especially in hot climates. Conventional vapor compression air conditioning systems are known to be energy intensive systems that rely mainly on electrical energy. Thus, there is a pressing need to decrease the reliance on active cooling systems by the introduction of passive cooling strategies and efficient sustainable buildings. This study proposes an effective passive cooling system that integrates a cross-flow dew point indirect evaporative cooler (DP-IEC) supplying cool clean air to an office space. Validated mathematical models were used to assess the integrated system’s ability in maintaining acceptable thermal comfort and IAQ levels at minimal energy and water consumption. The simulations were carried out for the peak load month for a case study of an occupied office located in the semi-arid and hot Lebanese inland region. The proposed system was able to meet the space thermal and IAQ constraints (average indoor temperature of 25.6 °C, CO2 concentration below 600 ppm). The optimized system operation yielded a daily energy and water consumption of 0.65 kWh and 52 L with a reduction of 80 % in the running cost as compared to the conventional mechanical system.
10

Rublevskyi, Anton, Carl Johnson, Chuang Hwee Tay, Darren Main, and Axle Herrera. "Abandonment Solution for Wells With Gauge Cables: An Engineered Self-Sealing Cement System." In ASME 2021 40th International Conference on Ocean, Offshore and Arctic Engineering. American Society of Mechanical Engineers, 2021. http://dx.doi.org/10.1115/omae2021-62420.

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Abstract With an increasing number of wells transitioning to their abandonment stages, associated operational efficiency and cost cutting have become a major focus in the industry. An operator had an objective to permanently abandon an offshore well that was suspended in 2016. The key challenge was to develop a long-term well abandonment solution leaving the completion tubing and gauge cables in the well. All the associated operations had to be completed utilizing a lightweight well intervention vessel. Traditionally, retrieving the entire 5 ½-in. production tubing during plug and abandonment operations has added operational complexity and costs, which increases the risk of exposure to health, safety, and environment (HSE) hazards. Alternatively, a sealant technique placing cement through and around the completion tubing with gauge cables in situ exists. However, this technique is associated with a heightened risk of leak path development over time. Ongoing experimental work suggested that enhancements to the conventional cement sealant systems are beneficial to improve long-term sealing; thus, an active self-sealing cement (SSC) system that would seal microannuli or small fissures around the tubing and gauge cables was designed. The set cement sealant characteristics include low Young’s modulus to resist failure from wellbore stresses and the ability to regenerate the original seal upon contact with any hydrocarbons that may seep through any isolation defects through the life of the abandoned well. To achieve proper cement placement, advanced fluid simulation software and carefully tailored fluid density and rheology profiles were used. During the operation, a plug of the SSC sealant was pumped through the production tubing and squeezed into the perforations to create a permanent barrier across the reservoir section. Next, a mechanical plug was set inside the production tubing to isolate the lower section, and the tubing was perforated to provide access to the A-annulus above; subsequently, a balanced plug of SSC system was spotted above. After 30 hours, the plug passed a 3.4-MPa [500-psi] verification pressure test. The operator estimated the operation saved 2 to 3 days of rig time, valued at approximately GBP 400,000 to 600,000. The operator also avoided the risk of leaving the well on long-term suspension with mechanical plugs while waiting for a rig to complete the isolation, and the operation minimized the number of intervention steps required for abandonment, thereby limiting scope growth. Operators are constantly looking for ways to increase reliability, improve efficiency, and minimize risks; and therefore, abandonment techniques are evolving. The developed solution is a novel and robust alternative to conventional well abandonment using an advanced cement sealant technology for the first time and an innovative placement technique.

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