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Статті в журналах з теми "Inverse and reverse location theory"

1

Kim, Se-Yun, Hyun-Chul Choi, Jae-Min Lee, and Jung-Woong Ra. "Inverse Scattering Scheme Based on the Moment Method in the Spectral Domain, Part I: Theory." Ultrasonic Imaging 14, no. 1 (January 1992): 16–28. http://dx.doi.org/10.1177/016173469201400102.

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Recently, electromagnetic and ultrasonic imaging of inhomogeneous objects by applying the moment-method procedures of forward scattering problems in the reverse sequence have been developed. In this paper, the inverse scattering formulation has been modified to be applicable in the spectral domain. Compared to previous schemes, the suggested formulation illustrates clearly the actual mechanism of the inverse scattering process by explicit separation of the contributions from several variables, such as the measurement location, basis function, and geometry of objects. The ill-posedness inherent in inverse scattering problems was also explained easily in this spectral scheme by the exponentially-decaying behavior of high-frequency spectral components of the scattered field. It implies that enlargement of the discretized cell size is a key factor in regularizing the ill-posedness. In particular, since the singular kernel to be integrated on each cell became regular in the modified scheme, various types of basis functions instead of pulse function were adopted without additional difficulties. This advantage is expected to play an important role in regularizing the noise effect by selecting polynomial basis function on the enlarged cells of discretization in the spectral inverse scattering scheme.
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2

Zhang, Lei, and Luming Jia. "Near-field imaging for an obstacle above rough surfaces with limited aperture data." Inverse Problems & Imaging 15, no. 5 (2021): 975. http://dx.doi.org/10.3934/ipi.2021024.

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<p style='text-indent:20px;'>This paper is concerned with the scattering and inverse scattering problems for a point source incident wave by an obstacle embedded in a two-layered background medium. It is a nontrivial extension of the previous theoretical work on the inverse obstacle scattering in an unbounded structure [Commun. Comput. Phys., 26 (2019), 1274-1306]. By the potential theory of boundary integral equations, we derive a novel integral equation formula for the scattering problem, then the well-posedness of the system is proved. Based on the singularity analysis of integral kernels, we presented a numerical method for the integral equations. Furthermore, we developed a reverse time migration method for the corresponding composite inverse scattering problem with the limited aperture data. Numerical experiments show that the proposed method is effective to recover the support of an unknown obstacle and the shape, location of the surfaces.</p>
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Osipov, Vasiliy, Sergey Kuleshov, Alexandra Zaytseva, and Alexey Aksenov. "Approach for the COVID-19 Epidemic Source Localization in Russia Based on Mathematical Modeling." Informatics and Automation 20, no. 5 (August 13, 2021): 1065–89. http://dx.doi.org/10.15622/20.5.3.

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The paper presents the results of statistical data from open sources on the development of the COVID-19 epidemic processing and a study сarried out to determine the place and time of its beginning in Russia. An overview of the existing models of the processes of the epidemic development and methods for solving direct and inverse problems of its analysis is given. A model for the development of the COVID-19 epidemic via a transport network of nine Russian cities is proposed: Moscow, St. Petersburg, Nizhny Novgorod, Rostov-on-Don, Krasnodar, Yekaterinburg, Novosibirsk, Khabarovsk and Vladivostok. The cities are selected both by geographic location and by the number of population. The model consists of twenty seven differential equations. An algorithm for reverse analysis of the epidemic model has been developed. The initial data for solving the problem were the data on the population, the intensity of process transitions from one state to another, as well as data on the infection rate of the population at given time moments. The paper also provides the results of a detailed analysis of the solution approaches to modeling the development of epidemics by type of model (basic SEIR model, SIRD model, adaptive behavioral model, modified SEIR models), and by country (in Poland, France, Spain, Greece and others) and an overview of the applications that can be solved using epidemic spread modeling. Additional environmental parameters that affect the modeling of the spread of epidemics and can be taken into account to improve the accuracy of the results are considered. Based on the results of the modeling, the most likely source cities of the epidemic beginning in Russia, as well as the moment of its beginning, have been identified. The reliability of the estimates obtained is largely determined by the reliability of the statistics used on the development of COVID-19 and the available data on transportation network, which are in the public domain.
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Visnjic, Jelena, Ivana Stanisev, and Yuanyuan Ke. "Reverse order law and forward order law for the (b, c)-inverse." Electronic Journal of Linear Algebra 39 (July 13, 2023): 379–94. http://dx.doi.org/10.13001/ela.2023.7807.

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The reverse order law and the forward order law have been studied for various types of generalized inverses. The $(b,c)$-inverse is a generalization of some well known generalized inverses, such as the Moore-Penrose inverse, the Drazin inverse, the core inverse, etc. In this paper, the reverse order law for the $(b,c)$-inverse, in a unital ring, is investigated and an equivalent condition for this law to hold for the $(b,c)$-inverse is derived. Also, some known results on this topic are generalized. Furthermore, the forward order law for the $(b,c)$-inverse in a ring with a unity is introduced, for different choices of $b$ and $c$. Moreover, as corollaries of obtained results, equivalent conditions for the reverse order law and the forward order law for the inverse along an element are derived.
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Castro-Gonzalez, Nieves, and Robert Hartwig. "Perturbation results and the forward order law for the Moore-Penrose inverse of a product." Electronic Journal of Linear Algebra 34 (February 21, 2018): 514–25. http://dx.doi.org/10.13001/1081-3810.3365.

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New expressions are given for the Moore-Penrose inverse of a product $AB$ of two complex matrices. Furthermore, an expression for $(AB)\dg - B\dg A\dg$ for the case where $A$ or $B$ is of full rank is provided. Necessary and sufficient conditions for the forward order law for the Moore-Penrose inverse of a product to hold are established. The perturbation results presented in this paper are applied to characterize some mixed-typed reverse order laws for the Moore-Penrose inverse, as well as the reverse order law.
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6

Zheng, Jie. "The solution of inverse matrix by using unary polynomial ring theory." Highlights in Science, Engineering and Technology 22 (December 7, 2022): 287–92. http://dx.doi.org/10.54097/hset.v22i.3390.

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Matrix is in the core position in algebra, and the inverse matrix is particularly important. So far, there are adjoint matrix method, elementary transformation method, block matrix method and so on in solving the inverse matrix. In this paper, we will introduce a method of seeking the inverse matrix by using unary polynomial ring theory. This method can reverse the matrix equation into the algebra equation, cleverly avoiding the complex matrix equation.
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Martin, Benjamin T., Stephan B. Munch, and Andrew M. Hein. "Reverse-engineering ecological theory from data." Proceedings of the Royal Society B: Biological Sciences 285, no. 1878 (May 16, 2018): 20180422. http://dx.doi.org/10.1098/rspb.2018.0422.

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Ecologists have long sought to understand the dynamics of populations and communities by deriving mathematical theory from first principles. Theoretical models often take the form of dynamical equations that comprise the ecological processes (e.g. competition, predation) believed to govern system dynamics. The inverse of this approach—inferring which processes and ecological interactions drive observed dynamics—remains an open problem in ecology. Here, we propose a way to attack this problem using a machine learning method known as symbolic regression, which seeks to discover relationships in time-series data and to express those relationships using dynamical equations. We found that this method could rapidly discover models that explained most of the variance in three classic demographic time series. More importantly, it reverse-engineered the models previously proposed by theoretical ecologists to describe these time series, capturing the core ecological processes these models describe and their functional forms. Our findings suggest a potentially powerful new way to merge theory development and data analysis.
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Omidi, Shahede, Jafar Fathali, and Morteza Nazari. "Inverse and reverse balanced facility location problems with variable edge lengths on trees." OPSEARCH 57, no. 2 (December 2, 2019): 261–73. http://dx.doi.org/10.1007/s12597-019-00428-6.

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Nazari, Morteza, and Jafar Fathali. "Inverse and Reverse 2-facility Location Problems with Equality Measures on a Network." Iranian Journal of Mathematical Sciences and Informatics 18, no. 1 (April 1, 2023): 211–25. http://dx.doi.org/10.52547/ijmsi.18.1.211.

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Qin, Yingying, and Zhiping Xiong. "A Note on the Reverse Order Law for g-Inverse of Operator Product." Axioms 11, no. 5 (May 12, 2022): 226. http://dx.doi.org/10.3390/axioms11050226.

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The generalized inverse has many important applications in aspects of the theoretical research of matrices and statistics. One of the core problems of the generalized inverse is finding the necessary and sufficient conditions of the reverse order laws for the generalized inverse of the operator product. In this paper, we study the reverse order law for the g-inverse of an operator product T1T2T3 using the technique of matrix form of bounded linear operators. In particular, some necessary and sufficient conditions for the inclusion T3{1}T2{1}T1{1} ⊆ (T1T2T3){1} is presented. Moreover, some finite dimensional results are extended to infinite dimensional settings.
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Дисертації з теми "Inverse and reverse location theory"

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Acar, Alper. "Optimal Urban Planning and Housing Prices : a Spatial Analysis." Electronic Thesis or Diss., Bourgogne Franche-Comté, 2024. http://www.theses.fr/2024UBFCG008.

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La thèse étudie l'impact de l'aménagement urbain optimal surla diffusion des prix des logements dans un marché immobilier local. À travers une analyse du champ de la localisation optimale et de l'économétrie spatiale, cette étude vise à considérer comment les propriétés des graphes et les modèles de localisation optimale peuvent contribuer à mieux comprendre et à évaluer les impacts des effets de multiplicateur spatial dans l'économie. Pour ce faire, la recherche s'appuie sur une méthodologie combinant la création d'outils d'aide à la décision et l'étude des prix immobiliers par un modèle économétrique spatiale hiérarchique. Les résultats démontrent que la prise en compte des relations spatiales optimales permet une étude plus précise des impacts de l'aménagement urbain sur la diffusion des prix. A contrario, la considération de relations spatiales “classiques" sur ou sous-estime les impacts
This dissertation studies the effect of optimal urban planning on housing prices diffusion in local real-estate markets. The study uses facility location theory and spatial econometrics to investigate how graph properties and optimal location models can contribute to a better understanding and evaluation of the impact of spatial multiplier effects in the economy. To this end, the research is based on a methodology that combines the creation of decision-support tools and the study of real estate prices using hierarchical spatial econometric models. The results states that using optimal spatial relationships enables a more precise analysis of the impacts of urban planning on the diffusion of prices. Conversely, the consideration of “classical” spatial relationships either underestimates or overestimates the spatial impacts
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Nguyen, Kien Trung [Verfasser]. "Inverse Location Theory : with Ordered Median Function and Other Extensions / Kien Trung Nguyen." Berlin : epubli GmbH, 2014. http://d-nb.info/1063826829/34.

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Cerf, Sophie. "control theory for computing systems : application to big-data cloud services & location privacy protection." Thesis, Université Grenoble Alpes (ComUE), 2019. http://www.theses.fr/2019GREAT024.

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Cette thèse présente une application de la théorie du contrôle pour les systèmes informatiques. Un algorithme de contrôle peut gérer des systèmes plus grands et plus complexes, même lorsqu'ils sont particulièrement sensibles aux variations de leur environnement. Cependant, l'application du contrôle aux systèmes informatiques soulève plusieurs défis, par exemple dû au fait qu'aucune physique ne les régisse. D'une part, le cadre mathématique fourni par la théorie du contrôle peut être utilisé pour améliorer l'automatisation, la robustesse et la fiabilité des systèmes informatiques. D'autre part, les défis spécifiques de ces cas d'étude permettent d'élargir la théorie du contrôle elle-même. L'approche adoptée dans ce travail consiste à utiliser deux systèmes informatiques d'application: la protection de vie privée liée à la mobilité et les performances des services clouds. Ces deux cas d'utilisation sont complémentaires par la nature de leurs technologies, par leur échelle et par leurs utilisateurs finaux.La popularité des appareils mobiles a favorisé la diffusion et la collecte des données de localisation, que ce soit pour que l'utilisateur bénéficie d'un service personnalisé (e.g. une planification d'itinéraire) ou pour que le prestataire de services tire des informations utiles des bases de données de mobilité (e.g. la popularité de lieux). En effet, de nombreuses informations peuvent être extraites de données de localisation, y compris des données personnelles très sensibles. Pour remédier à cette atteinte à la vie privée, des mécanismes de protection spécifiques aux données de mobilité (LPPM) ont été élaborés. Ce sont des algorithmes qui modifient les données de localisation de l'utilisateur, dans le but de cacher des informations sensibles. Cependant, ces outils ne sont pas facilement configurables par des non experts et sont des processus statiques qui ne s'adaptent pas à la mobilité de l'utilisateur. Dans cette thèse, nous développons deux outils, l'un pour les bases de données déjà collectées et l'autre pour l'utilisation en ligne, qui garantissent aux utilisateurs des niveaux de protection de la vie privée et de préservation de la qualité des services en configurant les LPPMs. Nous présentons la première formulation du problème en termes de théorie du contrôle (système et contrôleur, signaux d’entrée et de sortie), et un contrôleur PI pour servir de démonstration d’applicabilité. Dans les deux cas, la conception, la mise en œuvre et la validation ont été effectuées par le biais d'expériences utilisant des données d'utilisateurs réels recueillies sur le terrain.L'essor récent des bigdata a conduit au développement de programmes capables de les analyser, tel que MapReduce. Les progrès des pratiques informatiques ont également permis d'établir le modèle du cloud (où il est possible de louer des ressources de bas niveau pour permettre le développement d'applications de niveau supérieur sans se préoccuper d'investissement ou de maintenance) comme une solution incontournable pour tous types d'utilisateurs. Garantir les performances des tâches MapReduce exécutées sur les clouds est donc une préoccupation majeure pour les grandes entreprises informatiques et leurs clients. Dans ce travail, nous développons des techniques avancées de contrôle du temps d'exécution des tâches et de la disponibilité de la plate-forme en ajustant la taille du cluster de ressources et en réalisant un contrôle d'admission, fonctionnant quelle que soit la charge des clients. Afin de traiter les non linéarités de MapReduce, un contrôleur adaptatif a été conçu. Pour réduire l'utilisation du cluster (qui entraîne des coûts financiers et énergétiques considérables), nous présentons une nouvelle formulation du mécanisme de déclenchement du contrôle événementiel, combiné à un contrôleur prédictif optimal. L'évaluation est effectuée sur un benchmark s'exécutant en temps réel sur un cluster, et en utilisant des charges de travail industrielles
This thesis presents an application of Control Theory for Computing Systems. It aims at investigating techniques to build and control efficient, dependable and privacy-preserving computing systems. Ad-hoc service configuration require a high level of expertise which could benefit from automation in many ways. A control algorithm can handle bigger and more complex systems, even when they are extremely sensitive to variations in their environment. However, applying control to computing systems raises several challenges, e.g. no physics governs the applications. On one hand, the mathematical framework provided by control theory can be used to improve automation and robustness of computing systems. Moreover, the control theory provides by definition mathematical guarantees that its objectives will be fulfilled. On the other hand, the specific challenges of such use cases enable to expand the control theory itself. The approach taken in this work is to use two application computing systems: location privacy and cloud control. Those two use-cases are complementary in the nature of their technologies and softwares, their scale and in their end-users.The widespread of mobile devices has fostered the broadcasting and collection of users’ location data. It could be for the user to benefit from a personalized service (e.g. weather forecast or route planning) or for the service provider or any other third party to derive useful information from the mobility databases (e.g. road usage frequency or popularity of places). Indeed, many information can be retrieved from location data, including highly sensitive personal data. To overcome this privacy breach, Location Privacy Protection Mechanisms (LPPMs) have been developed. They are algorithm that modify the user’s mobility data, hopefully to hide some sensitive information. However, those tools are not easily configurable by non experts and are static processes that do not adapt to the user’s mobility. We develop two tools, one for already collected databases and one for online usage, that, by tuning the LPPMs, guarantee to the users objective-driven levels of privacy protection and of service utility preservation. First, we present an automated tool able to choose and configure LPPMs to protect already collected databases while ensuring a trade-off between privacy protection and database processing quality. Second, we present the first formulation of the location privacy challenge in control theory terms (plant and control, disturbance and performance signals), and a feedback controller to serve as a proof of concept. In both cases, design, implementation and validation has been done through experiments using data of real users collected on the field.The surge in data generation of the last decades, the so-called bigdata, has lead to the development of frameworks able to analyze them, such as the well known MapReduce. Advances in computing practices has also settled the cloud paradigms (where low-level resources can be rented to allow the development of higher level application without dealing with consideration such as investment in hardware or maintenance) as premium solution for all kind of users. Ensuring the performances of MapReduce jobs running on clouds is thus a major concern for the big IT companies and their clients. In this work, we develop advanced monitoring techniques of the jobs execution time and the platform availability by tuning the resource cluster size and realizing admission control, in spite of the unpredictable client workload. In order to deal with the non linearities of the MapReduce system, a robust adaptive feedback controller has been designed. To reduce the cluster utilization (leading to massive financial and energetic costs), we present a new event-based triggering mechanism formulation combined with an optimal predictive controller. Evaluation is done on a MapReduce benchmark suite running on a large-scale cluster, and using real jobs workloads
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Li, Ka Lok. "Location and Relocation of Seismic Sources." Doctoral thesis, Uppsala universitet, Geofysik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-327038.

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This dissertation is a comprehensive summary of four papers on the development and application of new strategies for locating tremor and relocating events in earthquake catalogs. In the first paper, two new strategies for relocating events in a catalog are introduced. The seismicity pattern of an earthquake catalog is often used to delineate seismically active faults. However, the delineation is often hindered by the diffuseness of earthquake locations in the catalog. To reduce the diffuseness and simplify the seismicity pattern, a relocation and a collapsing method are developed and applied. The relocation method uses the catalog event density as an a priori constraint for relocations in a Bayesian inversion. The catalog event density is expressed in terms of the combined probability distribution of all events in the catalog. The collapsing method uses the same catalog density as an attractor for focusing the seismicity in an iterative scheme. These two strategies are applied to an aftershock sequence after a pair of earthquakes which occurred in southwest Iceland, 2008. The seismicity pattern is simplified by application of the methods and the faults of the mainshocks are delineated by the reworked catalog. In the second paper, the spatial distribution of seismicity of the Hengill region, southwest Iceland is analyzed. The relocation and collapsing methods developed in the first paper and a non-linear relocation strategy using empirical traveltime tables are used to process a catalog collected by the Icelandic Meteorological Office. The reworked catalog reproduces details of the spatial distribution of seismicity that independently emerges from relative relocations of a small subset of the catalog events. The processed catalog is then used to estimate the depth to the brittle-ductile transition. The estimates show that in general the northern part of the area, dominated by volcanic processes, has a shallower depth than the southern part, where tectonic deformation predominates. In the third and the fourth papers, two back-projection methods using inter-station cross correlations are proposed for locating tremor sources. For the first method, double correlations, defined as the cross correlations of correlations from two station pairs sharing a common reference station, are back projected. For the second method, the products of correlation envelopes from a group of stations sharing a common reference station are back projected. Back projecting these combinations of correlations, instead of single correlations, suppresses random noise and reduces the strong geometrical signature caused by the station configuration. These two methods are tested with volcanic tremor at Katla volcano, Iceland. The inferred source locations agree with surface observations related to volcanic events which occurred during the tremor period.
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Mosher, Stephen Glenn. "Neural Network Applications in Seismology." Thesis, Université d'Ottawa / University of Ottawa, 2021. http://hdl.handle.net/10393/42329.

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Neural networks are extremely versatile tools, as evidenced by their widespread adoption into many fields in the sciences and beyond, including the geosciences. In seismology neural networks have been primarily used to automatically detect and discriminate seismic signals within time-series data, as well as provide location estimates for their sources. However, as neural network research has significantly progressed over the past three decades, so too have its applications in seismology. Such applications now include earthquake early warning systems based on smartphone data collected from large numbers of users, the prediction of peak ground acceleration from earthquake source parameters, the efficient computation of synthetic seismograms, providing probabilistic estimates of solutions to geophysical inverse problems, and many others. This thesis contains three components, each of which explore novel uses of neural networks in seismology. In the first component, a previously established earthquake detection and location method is supplemented with a neural network in order to automate the detection process. The detection procedure is then applied to a large volume of seismic data. In addition to automating the detection process, the neural network removes the need for several user-defined thresholds, subjective criteria otherwise necessary for the method. In the second component, a novel approach is developed for inverting seafloor compliance data recorded by ocean-bottom seismometers for the shallow shear-wave velocity structure of oceanic tectonic plates. The approach makes use of mixture density networks, a type of neural network designed to provide probabilistic estimates of solutions to inverse problems, something that standard neural networks are incapable of. In the final component of this thesis, the mixture density network approach to compliance inversion is applied to a group of ocean-bottom seismometers deployed along the continental shelf of the Cascadia Subduction Zone in order to investigate shelf sediment properties.
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Miller, Karen Ann. "An Inverse Source Location Algorithm for Radiation Portal Monitor Applications." Thesis, 2010. http://hdl.handle.net/1969.1/ETD-TAMU-2010-05-7772.

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Radiation portal monitors are being deployed at border crossings throughout the world to prevent the smuggling of nuclear and radiological materials; however, a tension exists between security and the free-flow of commerce. Delays at ports-of-entry have major economic implications, so it is imperative to minimize portal monitor screening time. We have developed an algorithm to locate a radioactive source using a distributed array of detectors, specifically for use at border crossings. To locate the source, we formulated an optimization problem where the objective function describes the least-squares difference between the actual and predicted detector measurements. The predicted measurements are calculated by solving the 3-D deterministic neutron transport equation given an estimated source position. The source position is updated using the steepest descent method, where the gradient of the objective function with respect to the source position is calculated using adjoint transport calculations. If the objective function is smaller than a predetermined convergence criterion, then the source position has been identified. To test the algorithm, we first verified that the 3-D forward transport solver was working correctly by comparing to the code PARTISN (Parallel Time-Dependent SN). Then, we developed a baseline scenario to represent a typical border crossing. Test cases were run for various source positions within each vehicle and convergence criteria, which showed that the algorithm performed well in situations where we have perfect knowledge of parameters such as the material properties of the vehicles. We also ran a sensitivity analysis to determine how uncertainty in various parameters-the optical thickness of the vehicles, the fill level in the gas tank, the physical size of the vehicles, and the detector efficiencies-affects the results. We found that algorithm is most sensitive to the optical thickness of the vehicles. Finally, we tested the simplifying assumption of one energy group by using measurements obtained from MCNPX (Monte Carlo N-Particle Extended). These results showed that the one-energy-group assumption will not be sufficient if the code is deployed in a real-world scenario. While this work describes the application of the algorithm to a land border crossing, it has potential for use in a wide array of nuclear security problems.
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Pilarski, Patrick Michael. "Computational analysis of wide-angle light scattering from single cells." Phd thesis, 2009. http://hdl.handle.net/10048/774.

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Thesis (Ph.D.)--University of Alberta, 2009.
Title from PDF file main screen (viewed on Apr. 1, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Doctor of Philosophy, Department of Electrical and Computer Engineering, University of Alberta. Includes bibliographical references.
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Частини книг з теми "Inverse and reverse location theory"

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Mendola, Joseph. "Space, Time, and Location." In Experience and Possibility, 71–99. Oxford University Press, 2021. http://dx.doi.org/10.1093/oso/9780198869764.003.0004.

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This chapter is an account of the particularity of spatial and temporal regions as they appear within our experience. It argues that the spatial and temporal relations of these regions are sufficient to individuate them, despite standard objections. This involves a kind of moderate substantivalism about space. The chapter also explores some of the complex modal structure of the spatial relations in question, relevant for instance to geometric truth and the way in which things seem to reverse in mirrors. The eternalist view of time presumed by this account is defended against alternative conceptions of time such as presentism and the moving spotlight theory.
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Carretero-González, R., D. J. Frantzeskakis, and P. G. Kevrekidis. "Inverse Scattering Transform I – the KdV Equation*." In Nonlinear Waves & Hamiltonian Systems, 134–56. Oxford University PressOxford, 2024. http://dx.doi.org/10.1093/oso/9780192843234.003.0011.

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Abstract In this chapter we introduce one of the most important contributions to the theory of nonlinear waves and solitons: the Inverse Scattering Transform (IST). The central idea of the IST is to take an analogous approach to solving linear PDEs using Fourier transforms, but taking it a step further so as to tackle nonlinear wave equations. In a way, we can dub the IST as the nonlinear analogue of the Fourier transform. Its name derives from the idea of reverse-engineering the time evolution of a scattering potential from the time evolution of its scattered wave. Namely, the IST works in the inverse direction of the standard process whereby one usually wants to obtain the scattered wave given a scattering barrier (or potential). This elegant method will allow us to explicitly write one- and two-soliton solutions for the KdV and even extend it to the general case of N-solitons.
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Wilkinson, David G. "The theory and practice of in situ hybridization." In In Situ Hybridization, 1–22. Oxford University PressOxford, 1998. http://dx.doi.org/10.1093/oso/9780199636594.003.0001.

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Abstract The in situ detection of nucleic acid sequences, whether of genes on chromosomes or viruses, or of mRNA in tissues, provides a direct visualization of the spatial location of specific sequences that is crucial for elucidation of the organization and function of genes. As a consequence, methods of in situ hybridization have become important techniques in a number of fields, including diagnosis of chromosomal rearrangements, detection of viral infections, and analysis of gene function during embryonic development. In situ hybridization takes advantage of the specific annealing of complementary nucleic acid molecules, which can be DNA and/or RNA, through hydrogen bonds formed between bases attached to the sugar-phosphate backbone: adenine (A) anneals with thymine (T, in DNA) or uracil (U, in RNA), and cytosine (C) anneals with guanine (G). This base pairing underlies the formation of a double-stranded complex, in which one· strand has the opposite orientation to the other with respect to the sugar-phosphate backbone (Figure JA); the sequence is read from 5’ to 3’ (this refers to the positions of the sugar at which the phosphate residues are attached). Any nucleic acid sequence can therefore be specifically detected by use of a probe that is the ‘antisense’ reverse complementary sequence. An important practical asset is the speed with which such probes can be generated by the cloning of DNA sequences, amplification by the polymerase chain reaction (PCR), or the synthesis of oligonucleotides.
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4

V. Massaras, Leon. "Screenout Detection and Avoidance." In Recent Advances in Hydraulic Fracturing [Working Title]. IntechOpen, 2024. http://dx.doi.org/10.5772/intechopen.112450.

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A screenout (SO) event is defined as premature termination of a propped hydraulic fracture (PHF) treatment due to bridging of the proppant at a restriction, usually located at the near-wellbore area or at the perforations—and not at the perimeter tip of the fracture. Numerous Screenout Detection (SD) methodologies have been presented over the past 60 years which are designed to predict the likelihood of a SO event based on analysis of minifrac data, or real-time data—during the mainfrac. Three simple SD and numerous screenout avoidance (SA) methods are presented. The SD methods are: enhanced fracture entry friction (FEF) analysis, median ratio (MR) and inverse slope (IS). Analyses with the first two methods require data from a step-down test (SDT), while the third method uses data which are analyzed in real-time during the mainfrac. By knowing the potential for a SO event or by having advance warning of the onset of a SO event, one is able to apply design modifications for the mainfrac, or is able to initiate abrupt, or incremental step displacement (flush) and achieve SA, or to extend the PHF treatment to improve placement by attaining increased net-pressure gain. The theory and logic of the SDT and of the three methods includes discussion on: the balloon analogy, stagnation pressure, fracture toughness and fracture tip dilatancy. Both the MR and the IS methods do not require a computer or software and all three methods are very easy to use at the well location by the on-site engineer. All three methods are very inexpensive. Numerous publications have dealt with SA over the past 70 years, and have presented design modification procedures, and wellbore intervention procedures, which are presented briefly. These procedures when implemented individually, or in combination, have proven to be very useful in: Preventing SO events, achieving positive SA outcomes, by enabling the safe and effective placement of PHF treatments.
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Vijayakumar R, Vijay K, Sivaranjani P, and Priya V. "Detection of Network Attacks Based on Multiprocessing and Trace Back Methods." In Advances in Parallel Computing. IOS Press, 2021. http://dx.doi.org/10.3233/apc210111.

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The way of thinking of traffic observing for discovery of system assaults is predicated on a “gained information” viewpoint: current methods recognize either the notable assaults which they’re customized to alarm on, or those strange occasions that veer off from a known typical activity profile. These philosophies depend on an expert structure which gives the ideal data, either with respect to “marks” of the striking attacks or as anomaly free traffic datasets, adequately rich to make delegate profiles for commonplace movement traffic. The theory talks about the limitations of current information-based system to recognize organize assaults in an inexorably unpredictable and advancing Web, Described by ever-rising applications and an ever-expanding number of most recent system assaults. In an oppositely inverse viewpoint, we place the weight on the occasion of solo recognition strategies, fit for distinguishing obscure system assaults during a unique situation with none past information, neither on the attributes of the assault nor on the gauge traffic conduct. In view of the perception that an outsized portion of system assaults are contained during a little division of traffic flows, the proposition exhibits an approach to join basic bunching strategies to precisely distinguish and portray malignant flows. to bring up the practicality of such an information autonomous methodology, a solid multi-bunching-based location technique is created and assess its capacity to recognize and portray arrange assaults with none past information, utilizing bundle follows from two genuine operational systems. The methodology is acclimated identify and describe obscure vindictive flows, and spotlights on the identification and portrayal of ordinary and notable assaults, which encourages the translation of results. When contrasted with the predominant DDoS traceback techniques, the proposed system has assortment of favorable circumstances—it is memory no concentrated, proficiently adaptable, vigorous against parcel contamination, and free of assault traffic designs. The consequences of inside and out test and reenactment considers are introduced to exhibit the adequacy and effectiveness of the proposed strategy. It’s an uncommon test to traceback the wellspring of Circulated Disavowal of-Administration (DDoS) assaults inside the Web. In DDoS assaults, aggressors create a lot of solicitations to casualties through undermined PCs (zombies), with the point of keeping ordinary help or debasing from getting the norm of administrations. Because of this fundamental change, the proposed system conquers the acquired downsides of parcel stamping strategies, similar to weakness to bundle contaminations. The execution of the proposed strategy welcomes no changes on current steering programming. Moreover, this work builds up a hypothetical structure for assessing the insurance of IDS against mimicry assaults. It shows an approach to break the wellbeing of 1 distributed IDS with these strategies, and it tentatively affirms the capacity of various assaults by giving a worked model. The Project is intended by using Java 1.6 as face and MS SQL Server 2000 as backside. The IDE used is Net Beans 6.8.
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Тези доповідей конференцій з теми "Inverse and reverse location theory"

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Ogurtsova, Tetiana, Gennadiy Pochanin, Mykhail Nesterenko, Iryna Pochanina, and Vadym Ruban. "Determination of the Location of the Radiation Source." In 2024 IEEE 29th International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory (DIPED), 138–42. IEEE, 2024. http://dx.doi.org/10.1109/diped63529.2024.10706046.

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Lu, Xiaodong, and Pei-Feng Hsu. "Reverse Monte Carlo Method for Transient Radiative Transfer in Participating Media." In ASME 2003 International Mechanical Engineering Congress and Exposition. ASMEDC, 2003. http://dx.doi.org/10.1115/imece2003-41932.

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The Monte Carlo (MC) method has been widely used to solve radiative transfer problems due to its flexibility and simplicity in simulating the energy transport process in arbitrary geometries with complex boundary conditions. However, the major drawback of the conventional (or forward) Monte Carlo method is the long computational time for converged solution. Reverse or backward Monte Carlo (RMC) is considered as an alternative approach when solutions are only needed at certain locations and time. The reverse algorithm is similar to the conventional method, except that the energy bundle (photons ensemble) is tracked in a time-reversal manner. Its migration is recorded from the detector into the participating medium, rather than from the source to the detector as in the conventional MC. There is no need to keep track of the bundles that do not reach a particular detector. Thus, RMC method takes up much less computation time than the conventional MC method. On the other hand, RMC will generate less information about the transport process as only the information at the specified locations, e.g., detectors, is obtained. In the situation where detailed information of radiative transport across the media is needed the RMC may not be appropriate. RMC algorithm is most suitable for diagnostic applications where inverse analysis is required, e.g., optical imaging and remote sensing. In this study, the development of a reverse Monte Carlo method for transient radiative transfer is presented. The results of non-emitting, absorbing, and anisotropically scattering media subjected to an ultra short light pulse irradiation are compared with the forward Monte Carlo and discrete ordinates methods results.
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Yamamoto, Nozomi, Kotaro Fujita, Yuji Yamada, Shotaro Nakayama, Frederico Xavier de Melo, Suyang Chen, and Luis Arechiga Salinas. "Data-Driven Approach to Eliminate Internal Multiples Based on the Marchenko Method for a Carbonate Field in the Middle East." In ADIPEC. SPE, 2023. http://dx.doi.org/10.2118/216372-ms.

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Abstract Due to shale-carbonate alternating successions with a gentle structure, primary reflections are severely interfered by various orders of strong and complex internal multiples from the overburden to reservoir levels in carbonate fields in the Middle East. These factors make the existing techniques ineffective, and still pose various geophysical challenges. This study aims to demonstrate an innovative scheme to eliminate internal multiples based on the Marchenko equation, originated from a basis of the inverse scattering theory. The extension of the Marchenko equation to surface seismic data enables a retrieval of upgoing and downgoing Green’s functions between a virtual source in a given subsurface location and receivers at the surface. Such a key feature in the Marchenko method is capable of identifying and/or eliminating internal multiples in a data-driven fashion, without the need for explicit subsurface models or numerical modelling. The technique estimates all the downgoing reflections from the overburden level, interfering primaries in the target level as internal multiples, which are subsequently subtracted from the input data to derive internal-multiple free data. To thoroughly assess the value of the Marchenko method, a numerical study was conducted. The realistic earth model that incorporates subsurface contexts in a carbonate field in the Middle East was derived to generate synthetic data through finite-difference modelling. The Marchenko-based internal multiple elimination was applied to synthesized data followed by reverse time migration. As true subsurface responses are known here, this trial properly revealed the effectiveness of the algorithm. For a comparison purpose, we also performed another processing flow using conventional internal multiple elimination that makes use of periodicity and velocity discrimination. The Marchenko scheme successfully estimates various types of internal multiples, such as over- and under-corrected multiples and even flat internal multiples, regardless of their periodicities, at once. Despite its ability to effectively suppress internal multiples, the final imaging results indicate that underlaying primary events are still preserved. The technique also leads to notable improvements in the imaging quality as compared to conventional processing flow. In addition to the effectiveness of the Marchenko method, we also describe a dedicated workflow adapted in this study to deal with strong and complex internal multiples. The unique advantage of the Marchenko scheme over existing approaches is its ability to predict internal multiples in a data-driven manner without precisely specifying multiple generators, assuming behaviors of internal multiples, or requiring prior knowledge of subsurface context. The Marchenko method can be also implemented for various ways such as redatuming, target oriented imaging and velocity estimation, source inversion problem, passive seismic, and electromagnetic, which will certainly provide several aspects of additional value.
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Saparishvili, G., D. Kakulia, V. Tabatadze, M. Prishvin, R. Zaridze, and N. Uzunoglou. "Sensor's arbitrarily location mapping to the computer in high resolution image reconstruction experimental devices." In 2009 International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory (DIPED). IEEE, 2009. http://dx.doi.org/10.1109/diped.2009.5307271.

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Shubitidze, F., D. Karkashadze, B. Barrowes, and K. O'Neill. "An Analytical Expression for Estimating a Buried Object's Location, Orientation and Magnetic Polarization to Support UXO Discrimination." In 2007 XIIth International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory. IEEE, 2007. http://dx.doi.org/10.1109/diped.2007.4373591.

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Plakhtii, Vadym, Oleksandr Dumin, Oleksandr Prishchenko, Dmytro Shyrokorad, and Gennadiy Pochanin. "Influence of Noise Reduction on Object Location Classification by Artificial Neural Networks for UWB Subsurface Radiolocation." In 2019 XXIVth International Seminar/Workshop on Direct and Inverse Problems of Electromagnetic and Acoustic Wave Theory (DIPED). IEEE, 2019. http://dx.doi.org/10.1109/diped.2019.8882590.

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Tjokroamlnata, W. D., C. S. Tan, and W. R. Hawthorne. "A Design Study of Radial Inflow Turbines With Splitter Blades in Three-Dimensional Flow." In ASME 1994 International Gas Turbine and Aeroengine Congress and Exposition. American Society of Mechanical Engineers, 1994. http://dx.doi.org/10.1115/94-gt-036.

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An inverse design technique to design turbomachinery blading with splitter blades in three-dimensional flow is developed. It is based on the use of Clebsch transformation which allows the velocity field to be written as a potential part and a rotational part. It is shown that the rotational part can be expressed in terms of the mean swirl schedule (the circumferential average of the product of radius and tangential velocity) and the blade geometry that includes the main blade as well as the splitter blade. This results in an inverse design approach in which both the main and the splitter blade geometry are determined from a specification of the swirl schedule. Previous design study of a heavily-loaded radial inflow turbine, without splitter blades, for a rather wide variety of specified mean swirl schedules result in a blade shape with unacceptable non-radial blade filament; the resulting reduced static pressure distribution yields an “inviscid reverse flow region”1 covering almost the first half of the blade pressure surface. When the inverse design technique is applied to the design study of the turbine wheel with splitter blades, the results indicate that the use of splitter blades is an effective means for making the blade filament at an axial location more radial as well as a potential means for eliminating any “inviscid reverse flow” region that may exist on the pressure side of the blades.
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Furuta, Hiroki, Osamu Terashima, Yasuhiko Sakai, Kouji Nagata, Shunsuke Ishiguro, Masaharu Sakai, and Yasumasa Ito. "Experimental Study on the Internal Separated and Inverse Flow Between the Blades." In ASME 2013 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/imece2013-63090.

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The objective of this study is to investigate an internal separated flow between the blades of turbo machinery. Flow separation often causes undesirable phenomena such as an increase of the total pressure loss and a vibration of the machine. Therefore, understanding the characteristics of the separated flow in detail is very important for optimizing the machine to decrease the energy loss. In general, the separated flow involves a reverse flow near the solid wall in the separation bubble and its reattachment of the further downstream location. Hence, a typical hot-wire sensor is not useful for measuring the internal separated flow between the blades because it can detect only the magnitude of the flow velocity, not the flow direction. Based on this background, a self-developed tandem-type hot-wire sensor, by which both the magnitude and the flow direction can be detected, is used to measure the velocity field between the blades in this study. The tandem-type hot-wire sensor consists of two I-type hot-wire sensors and a small insulated elliptical cylinder placed between them. A calibration test is first conducted to validate its performance. Subsequently, the separated flow between the blades is measured with the tandem-type hot-wire sensor. The experimental apparatus consists of a closed-type test section which is connected to the nozzle exit of a blowout-type wind tunnel. In this test section, a sample of blade is set up. In this study, experiments are conducted with three kinds of blades with the different shapes (i.e., experiments are performed under three different conditions): a constant blade thickness from the leading edge to the trailing edge (Blade 1), a constant blade thickness from the leading edge to trailing edge but a rounded leading edge (Blade 2) and a thin blade thickness at the leading and trailing edges (Blade 3). In addition, the unsteady internal separated flow between the blades is also investigated by large-eddy simulation (LES) whose validity was fully confirmed in the previous study. The flow field and dissipation rate of the turbulent kinetic energy obtained by the simulation are discussed. Experimental and numerical results show that Blade 3 has a smallest separation bubble around the leading edge than that of Blade 1 and 2, and shows a smallest root mean square (RMS) value for the velocity fluctuation near the reattachment point than them. These differences of the size of separation bubble and velocity fluctuation were considered to be resulted in a decrease of the kinetic energy loss in the test section with Blade 3. Therefore, it can be concluded that the non-uniform thickness of the blade causes the decrease of the energy loss around the blade.
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Al-Musawi, Hawraa, Zeana AL-hindi, Noor Al- mamoori, Hasanain Shareef, Israa Ibraheam, and Wurood Kadhim. "Polycystic Ovary Syndrome under TNF and TAC Regulation." In 5th International Conference on Biomedical and Health Sciences, 289–92. Cihan University-Erbil, 2024. http://dx.doi.org/10.24086/biohs2024/paper.1357.

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Background: Polycystic Ovary Syndrome (PCOS) is a hormonal syndrome. One of an important disorder in women under physiological and immunological regulation. Affected by many factors and can diagnosis by many serological and immunological markers. Aim of study: Goal of present study target on tumor necrosis factor (TNF) and total antioxidant capacity (TAC) investigation. Methods: Current investigation involved 80 women (patients and control) with different ages from JANUARY 2022 to MARCH 2023 after recording information about patients. The cupric ion reduction antioxidant capacity (CUPRAC) method has been used to estimate TAC. ELISA test performed to evaluate TNF. Results: The highest percentage of disease was found in the age group [19-22]. It was the highest rate of 58%, followed by the age group [23-26] the lowest incidence rate in the age group [27-30] was 5%. According to location of patients in cities, varied between four cities included (Babylon, Karbala, Najaf and Baghdad) with a highest frequent showed in Babylon as (60%). Physiological study showed there are non-significant different between blood groups and PCOS under (P≤0.05), although varied the percentage in patients in four types (A+, B+, AB+ and O+) with highest percent in A+ about (38%). On other manner when measured total antioxidant capacity (TAC) also showed non-significant different between patients and control according to age group with a highest concentration in age group (19-22 y) in patients and control (3.7033± 0.8835 μm/l) (3.106± 0.427 μm/l) respectively. Immunological study, TNF concentration showed statistically significant difference (P≤0.05) in all age group compared to control with a highest level in (27-30y) as (170.207±3.68 pg/ml) for patients and (45.479±1.247 pg/ml) to control. Conclusion: The current study pointed about the correlation subject between TNF and TAC, results find there is an inverse correlation between them in patients’ group with present revers relationship in control group, that ensure an important of immune regulation. Those achieve the aim of our study.
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Luo, Tianyi, Peng Shan, and Xiaohe Yang. "The Variational Principle of a Rotor Passage Shock in the Circumferential Average Through Flow Inverse Problem of the Axial Compressors and Applications." In ASME 2023 Gas Turbine India Conference. American Society of Mechanical Engineers, 2023. http://dx.doi.org/10.1115/gtindia2023-117883.

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Abstract This paper advances the study of the shock phenomena in axial flow compressors to that of the behavior and effects of the rotor passage shock. Based on the design results of the S2m streamline curvature through flow inverse problem and blading of the axial flow compressors, taking the relative supersonic streamlines of the rotor as equivalent to a group of layers of the quasi-one-dimensional duct flow, this paper deduced a variational principle of the normal passage shock, interrupting the flow actually, stationed inside each layer of the rotor passage. It is found that the factors affecting the stationarity of the rotor passage shock include the variable cross-sectional area, the frictional and other on way losses, and the variable rotational radius of the duct flow. According to the variational principle, the stationary locations of the shock in these equivalent duct flows affected by three factors are obtained by the momentum relaxation method, and the location stability of these shocks is analyzed. In the applications to various types of transonic axial compressor rotors, first, the discontinuous entropy generation loss distributions along the cascades of each supersonic layer are set, to consider the boundary layer, oblique shock, normal passage shock, shock boundary layer interference, and trail edge losses. Second, applying the variational principle to the duct flows affected by these three factors for each streamline, all the shock locations that possess location stability are detected. Third, by comparing with the flow field results of the direct problem of Computational Fluid Dynamics, the dimensionless distribution law of the real entropy generation loss along the layer cascades is decided. Finally, by combining the shock lines from each equivalent duct flow corresponding to each streamline, a curved surface structure of the normal passage shock in a rotor passage is established. In the given design examples of three kinds of axial compressor stages, the three-dimensional structures of the normal passage shock obtained by this method are consistently in good agreement with the results of the direct problem of Computational Fluid Dynamics. These afford a first-term verification to this method for its effectiveness and wide applicability. This method provides a theory and a technology, in the through flow and blading inverse problem design phase of an axial compressor, to quickly predict the location and the curved surface shape of the normal passage shock, and to characterize approximately and evaluate relatively whether the design surge margin of a transonic stage is sufficient.
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Звіти організацій з теми "Inverse and reverse location theory"

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Buesseler, Buessele, Daniele Bianchi, Fei Chai, Jay T. Cullen, Margaret Estapa, Nicholas Hawco, Seth John, et al. Paths forward for exploring ocean iron fertilization. Woods Hole Oceanographic Institution, October 2023. http://dx.doi.org/10.1575/1912/67120.

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We need a new way of talking about global warming. UN Secretary General António Guterres underscored this when he said the “era of global boiling” has arrived. Although we have made remarkable progress on a very complex problem over the past thirty years, we have a long way to go before we can keep the global temperature increase to below 2°C relative to the pre-industrial times. Climate models suggest that this next decade is critical if we are to avert the worst consequences of climate change. The world must continue to reduce greenhouse gas emissions, and find ways to adapt and build resilience among vulnerable communities. At the same time, we need to find new ways to remove carbon dioxide from the atmosphere in order to chart a “net negative” emissions pathway. Given their large capacity for carbon storage, the oceans must be included in consideration of our multiple carbon dioxide removal (CDR) options. This report focused on ocean iron fertilization (OIF) for marine CDR. This is by no means a new scientific endeavor. Several members of ExOIS (Exploring Ocean Iron Solutions) have been studying this issue for decades, but the emergence of runaway climate impacts has motivated this group to consider a responsible path forward for marine CDR. That path needs to ensure that future choices are based upon the best science and social considerations required to reduce human suffering and counter economic and ecological losses, while limiting and even reversing the negative impacts that climate change is already having on the ocean and the rest of the planet. Prior studies have confirmed that the addition of small amounts of iron in some parts of the ocean is effective at stimulating phytoplankton growth. Through enhanced photosynthesis, carbon dioxide can not only be removed from the atmosphere but a fraction can also be transferred to durable storage in the deep sea. However, prior studies were not designed to quantify how effective this storage can be, or how wise OIF might be as a marine CDR approach. ExOIS is a consortium that was created in 2022 to consider what OIF studies are needed to answer critical questions about the potential efficiency and ecological impacts of marine CDR (http://oceaniron.org). Owing to concerns surrounding the ethics of marine CDR, ExOIS is organized around a responsible code of conduct that prioritizes activities for the collective benefit of our planet with an emphasis on open and transparent studies that include public engagement. Our goal is to establish open-source conventions for implementing OIF for marine CDR that can be assessed with appropriate monitoring, reporting, and verification (MRV) protocols, going beyond just carbon accounting, to assess ecological and other non-carbon environmental effects (eMRV). As urgent as this is, it will still take 5 to 10 years of intensive work and considerable resources to accomplish this goal. We present here a “Paths Forward’’ report that stems from a week-long workshop held at the Moss Landing Marine Laboratories in May 2023 that was attended by international experts spanning atmospheric, oceanographic, and social sciences as well as legal specialists (see inside back cover). At the workshop, we reviewed prior OIF studies, distilled the lessons learned, and proposed several paths forward over the next decade to lay the foundation for evaluating OIF for marine CDR. Our discussion very quickly resulted in a recommendation for the need to establish multiple “Ocean Iron Observatories’’ where, through observations and modeling, we would be able to assess with a high degree of certainty both the durable removal of atmospheric carbon dioxide—which we term the “centennial tonne”—and the ecological response of the ocean. In a five-year phase I period, we prioritize five major research activities: 1. Next generation field studies: Studies of long-term (durable) carbon storage will need to be longer (year or more) and larger (>10,000 km2) than past experiments, organized around existing tools and models, but with greater reliance on autonomous platforms. While prior studies suggested that ocean systems return to ambient conditions once iron infusion is stopped, this needs to be verified. We suggest that these next field experiments take place in the NE Pacific to assess the processes controlling carbon removal efficiencies, as well as the intended and unintended ecological and geochemical consequences. 2. Regional, global and field study modeling Incorporation of new observations and model intercomparisons are essential to accurately represent how iron cycling processes regulate OIF effects on marine ecosystems and carbon sequestration, to support experimental planning for large-scale MRV, and to guide decision making on marine CDR choices. 3. New forms of iron and delivery mechanisms Rigorous testing and comparison of new forms of iron and their potential delivery mechanisms is needed to optimize phytoplankton growth while minimizing the financial and carbon costs of OIF. Efficiency gains are expected to generate responses closer to those of natural OIF events. 4. Monitoring, reporting, and verification: Advances in observational technologies and platforms are needed to support the development, validation, and maintenance of models required for MRV of large-scale OIF deployment. In addition to tracking carbon storage and efficiency, prioritizing eMRV will be key to developing regulated carbon markets. 5. Governance and stakeholder engagement: Attention to social dimensions, governance, and stakeholder perceptions will be essential from the start, with particular emphasis on expanding the diversity of groups engaged in marine CDR across the globe. This feedback will be a critical component underlying future decisions about whether to proceed, or not, with OIF for marine CDR. Paramount in the plan is the need to move carefully. Our goal is to conduct these five activities in parallel to inform decisions steering the establishment of ocean iron observatories at multiple locations in phase II. When completed, this decadal plan will provide a rich knowledge base to guide decisions about if, when, where, and under what conditions OIF might be responsibly implemented for marine CDR. The consensus of our workshop and this report is that now is the time for actionable studies to begin. Quite simply, we suggest that some form of marine CDR will be essential to slow down and reverse the most severe consequences of our disrupted climate. OIF has the potential to be one of these climate mitigation strategies. We have the opportunity and obligation to invest in the knowledge necessary to ensure that we can make scientifically and ethically sound decisions for the future of our planet.
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