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Letteratura scientifica selezionata sul tema "Greens function methods"

Autore: Grafiati

Pubblicato: 13 aprile 2024

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Articoli di riviste sul tema "Greens function methods"

Simonne, Eric H., Doyle A. Smittle e Harry A. Mills. "An Irrigation Scheduling Model for Turnip Greens". Journal of the American Society for Horticultural Science 118, n. 6 (novembre 1993): 726–30. http://dx.doi.org/10.21273/jashs.118.6.726.

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An irrigation scheduling model for turnip (Brassica rapa L.) was validated using a line-source irrigation system in a 2-year field trial. The model used a water balance, a variable root length, and a crop factor function of plant age (i). Evapotranspiration was computed daily as class A pan evaporation times a crop factor [CF(i) = 0.365 + 0.0154i-0.00011i2]. Irrigation according to the model maintained soil water tension at <25 kPa at a 30-cm depth. When rainfall amounts were less than water use, leaf yields responded quadratically to irrigation rates, from 0% to 160% of the model rate, and the highest leaf yield with the lowest water applications corresponded to the model rate. Therefore, this model could replace the “feel or see” methods commonly used for scheduling irrigation of leafy vegetables grown in the southeastern United States.

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Forati, Ebrahim. "Density of Bloch states inside a one dimensional photonic crystal". Physica Scripta 97, n. 4 (17 marzo 2022): 045814. http://dx.doi.org/10.1088/1402-4896/ac5bbc.

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Abstract The density of Bloch modes inside a one dimensional photonic crystal (1D PC) is formulated based on its dispersion relations. This density function has applications in thermal emission inside a 1D PC, as well as controlling the dynamics of active materials embedded in them. After deriving the formulations, a practical 1D PC parameters in the visible range are used to calculate the density of transverse electric and transverse magnetic modes. Compared to the alternative methods such as using Dyadic Greens functions, this method is less complex and is exact. The method applies to any anisotropic medium for which the dispersion equations are available, analytically.

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Ujlayan, Amit, e Mohit Arya. "Approximate Solution of Riccati Differential Equation via Modified Greens Decomposition Method". Defence Science Journal 70, n. 4 (13 luglio 2020): 419–24. http://dx.doi.org/10.14429/dsj.70.14467.

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Riccati differential equations (RDEs) plays important role in the various fields of defence, physics, engineering, medical science, and mathematics. A new approach to find the numerical solution of a class of RDEs with quadratic nonlinearity is presented in this paper. In the process of solving the pre-mentioned class of RDEs, we used an ordered combination of Green’s function, Adomian’s polynomials, and Pade` approximation. This technique is named as green decomposition method with Pade` approximation (GDMP). Since, the most contemporary definition of Adomian polynomials has been used in GDMP. Therefore, a specific class of Adomian polynomials is used to advance GDMP to modified green decomposition method with Pade` approximation (MGDMP). Further, MGDMP is applied to solve some special RDEs, belonging to the considered class of RDEs, absolute error of the obtained solution is compared with Adomian decomposition method (ADM) and Laplace decomposition method with Pade` approximation (LADM-Pade`). As well, the impedance of the method emphasised with the comparative error tables of the exact solution and the associated solutions with respect to ADM, LADM-Pade`, and MGDMP. The observation from this comparative study exhibits that MGDMP provides an improved numerical solution in the given interval. In spite of this, generally, some of the particular RDEs (with variable coefficients) cannot be easily solved by some of the existing methods, such as LADM-Pade` or Homotopy perturbation methods. However, under some limitations, MGDMP can be successfully applied to solve such type of RDEs.

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Kustiyo. "DEVELOPMENT OF ANNUAL LANDSAT 8 COMPOSITE OVER CENTRAL KALIMANTAN, INDONESIA USING AUTOMATIC ALGORITHM TO MINIMIZE CLOUD". International Journal of Remote Sensing and Earth Sciences (IJReSES) 13, n. 1 (21 giugno 2017): 51. http://dx.doi.org/10.30536/j.ijreses.2016.v13.a2714.

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Since January 2013, Landsat 8 data can be freely accessed from LAPAN, making it possible to use the all available Landsat 8 data to produce the cloud-free Landsat 8 composite images. This study used Landsat 8 archive images in 2015, Operational Land Imager (OLI) sensor in 30 meter resolution, geometric correction level of L1T. The eight data in L1T of 118-062, southern part of Central Kalimantanwere used to produce a cloud-free composite image. Radiometric correction using Top of Atmosphere (TOA) and Bidirectional Reflectance Distribution Function (BRDF) algorithm to produce reflectance images have been applied, and then the most cloud-free pixels were selected in composite result. Six composite methods base on greens, open area and haze indices were compared, and the best one was selected using visual analysis. The analysis shows that the composite algorithm using Max (Max (NIR, SWIR1)/Green) produces the best image composite.

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Bigman, Galya, Krisann Oursler, Vincent Marconi e Alice Ryan. "Diet Quality, Muscle Mass, Strength and Function in Older Veterans With HIV". Current Developments in Nutrition 6, Supplement_1 (giugno 2022): 2. http://dx.doi.org/10.1093/cdn/nzac047.002.

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Abstract Objectives Older adults with HIV are at a higher risk for muscle loss and physical dysfunction which may be influenced by nutritional intake. The aim of this study was to examine dietary quality and its associations with muscle mass, strength, and function in older Veterans with HIV. Methods This is a cross-sectional study of sedentary older Veterans with HIV aged ≥50 years. Participants were tested for grip strength (kg) over body mass index (BMI, kg/m2), gait speed (4 meters walk, m/s), and appendicular lean mass (ALM) over BMI. Dietary quality was measured by the Healthy Eating Index (HEI-2015) using data obtained from three 24-hour dietary recalls. The HEI-2015 is comprised of 13 components (e.g., vegetables, greens and beans, fruits, dairy, and proteins). Each component was scored on density out of 1000 calories and summed to a total diet quality score (0–100). The total score was divided to high (HEI > 64, top 20%) vs. low (HEI ≤ 64). Multivariable linear regressions were developed to examine the HEI-2015 and its association with each muscle measure while controlling for age (years), race/ethnicity (Non-Hispanic (NH) Blacks vs. Whites), and BMI (only in gait speed model). Results Overall, 40 participants with mean (±SD) age of 60.6 ± 6.5 years were included. Of those, 95% were males, 70% NH-Blacks, and mean BMI was 28.2 ± 5.3. The total dietary quality score was 52.98 ± 12.3. Most of the participants consumed sufficient proteins (87.5%) but only 50.0% included sufficient intake of seafood and plant proteins. The results indicated a lack of intake in vegetables, greens and beans, fruits, whole grain, and dairy. After adjustment, the final models showed that higher dietary quality (HEI > 64 vs. HEI ≤ 64) was associated with grip strength/BMI (β = 0.37, 95% CI: 0.02–0.71), and did not reach statistical significance with ALM/BMI (β = 0.09, 95% CI: −0.04–0.22), or with gait speed (β = 0.05, 95% CI: −0.11–0.21). Conclusions In this sample, older Veterans with HIV tended to have a low diet quality with insufficient intake of imperative foods which is associated with reduced muscular strength. High dietary quality might be associated with improved physical function in this population that needs to be investigated in larger and prospective studies. Funding Sources Supported by the department of Veterans Affairs I01RX000667, I01 RX002790 and VA Advanced Fellowship Baltimore GRECC

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Bigman, Galya, e Marius Emil Rusu. "Low Dietary Intakes of Vitamin K and Leafy Green Vegetables Are Individually Associated With Low Cognitive Functioning in A National Sample of U.S. Older Adults". Current Developments in Nutrition 5, Supplement_2 (giugno 2021): 1306. http://dx.doi.org/10.1093/cdn/nzab059_007.

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Abstract Objectives This study aimed to examine the individual associations between dietary intake of vitamin K and leafy green vegetables with cognitive functioning in the US population of adults aged 60 years or older. Methods Cross-sectional data of older adults (≥60years; n = 2,342) from the 2011–2014 NHANES were analyzed. Dietary data were assessed by two 24-hour dietary recalls. ‘Low intake of vitamin K’ was defined as below the recommended daily intake (RDI) (i.e.,< 90mcg for women, < 120mcg for men). ‘Low intake of leafy green vegetables’ was defined as consuming below 90gr a day of green vegetables (e.g., broccoli, asparagus, green pees and beans) and below 30gr a day of leafy greens (e.g., kale, spinach, celery, and lettuce). The cognitive functioning assessment included four separate tests and their ‘overall score’: (1) The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) word learning test; (2) Delayed Word Recall (DWR); (3) the Animal Fluency Test (AFT); (4) the Digit Symbol Substitution Test (DSST). Low cognitive functioning was defined as receiving the lowest 20th percentile on each test score. Weighted logistic regressions examined the study aims by tests while controlling for associated covariates: age, sex, race/ethnicity, socioeconomics, body mass index, lifestyle factors, energy intake, chronic diseases, and antithrombotic medication. Results More than half of the sample (55%) did not consume sufficient intake of vitamin K a day, and about two thirds (66%) were defined as having low intake of leafy green vegetables. The multivariable model showed that participants with low intake of vitamin K are more likely, by 45–111%, to have low cognitive functioning than those with sufficient intake of vitamin K (overall score: Odds Ratio (OR) = 1.75, 95% CI: 1.36–2.26). Participants with low intake of leafy green vegetables had higher odds of having low cognitive functioning in three tests (i.e., CERAD, DWR, AFT) (ORs = 1.40–1.57) and in the overall test score (OR = 1.46, 95% CI: 1.14–1.87) than those who consumed ≥90 gr of green vegetables or ≥30 gr of leafy greens a day. Conclusions Low intakes of dietary vitamin K and leafy green vegetables might be linked with cognitive function impairment in older adults. The causality of such associations needs to be examined using prospective study design or interventions. Funding Sources N/A.

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Mickus, Ignas, Jeremy A. Roberts e Jan Dufek. "APPLICATION OF RESPONSE MATRIX METHOD TO TRANSIENT SIMULATIONS OF NUCLEAR SYSTEMS". EPJ Web of Conferences 247 (2021): 04014. http://dx.doi.org/10.1051/epjconf/202124704014.

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Until recently, reactor transient problems were exclusively solved by approximate deterministic methods. The increase in available computing power made it feasible to approach the transient analyses with time-dependent Monte Carlo methods. These methods offer the first-principle solution to the space-time evolution of reactor power by explicitly tracking prompt neutrons, precursors of delayed neutrons and delayed neutrons in time and space. Nevertheless, a very significant computing cost is associated with such methods. The general benefits of the Monte Carlo approach may be retained at a reduced computing cost by applying a hybrid stochastic-deterministic computing scheme. Among such schemes are those based on the fission matrix and the response matrix formalisms. These schemes aim at estimating a variant of the Greens function during a Monte Carlo transport calculation, which is later used to formulate a deterministic approach to solving a space-time dependent problem. In this contribution, we provide an overview of the time-dependent response matrix method, which describes a system by a set of response functions. We have recently suggested an approach where the functions are determined during a Monte Carlo criticality calculation and are then used to deterministically solve the space-time behaviour of the system. Here, we compare the time-dependent response matrix solution with the transient fission matrix and the time-dependent Monte Carlo solutions for a control rod movement problem in a mini-core reactor geometry. The response matrix formalism results in a set of loosely connected equations which offers favourable scaling properties compared to the methods based on the fission matrix formalism.

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Klyuev, Dmitriy S., e Yulia V. Sokolova. "Singular integral equation for an electric dipole taking into account the finite metal conductivity from which it is made". Physics of Wave Processes and Radio Systems 24, n. 4 (16 gennaio 2022): 13–18. http://dx.doi.org/10.18469/1810-3189.2021.24.4.13-18.

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A singular integral equation for an electric dipole has been obtained, which makes it possible to take into account the finite conductivity of the metal from which it is made. The derivation of the singular integral equation is based on the application of the Greens function for free space, written in a cylindrical coordinate system, taking into account the absence of the dependence of the field on the azimuthal coordinate, on a point source located on the surface of an electric dipole. Methods for its solution are proposed. In contrast to the well-known mathematical models of an electric dipole, built in the approximation of an ideal conductor, the use of the singular integral equation obtained in this work makes it possible to take into account heat losses and calculate the efficiency.

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Simons, Jack. "Equations of Motion Theory for Electron Affinities". Collection of Czechoslovak Chemical Communications 70, n. 5 (2005): 579–604. http://dx.doi.org/10.1135/cccc20050579.

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The ab initio calculation of molecular electron affinities (EA) and ionization potentials (IP) is a difficult task because the energy of interest is a very small fraction of the total electronic energy of the parent species. For example, EAs typically lie in the 0.01-10 eV range, but the total electronic energy of even a small molecule, radical, or ion is usually several orders of magnitude larger. Moreover, the EA or IP is an intensive quantity but the total energy is an extensive quantity, so the difficulty in evaluating EAs and IPs to within a fixed specified (e.g., ±0.1 eV) accuracy becomes more and more difficult as the system's size and number of electrons grows. The situation becomes especially problematic when studying extended systems such as solids, polymers, or surfaces for which the EA or IP is an infinitesimal fraction of the total energy. EOM methods such as the author developed in the 1970s offer a route to calculating the intensive EAs and IPs directly as eigenvalues of a set of working equations. A history of the development of EOM theories as applied to EAs and IPs, their numerous practical implementations, and their relations to Greens function or propagator theories are given in this contribution. EOM methods based upon Møller-Plesset, multiconfiguration self-consistent field, and coupled-cluster reference wave functions are included in the discussion as is the application of EOM methods to metastable states of anions.

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KIM LISTER, C. J. "PRECISION MEASUREMENTS OF ELECTROMAGNETIC TRANSITION RATES IN A=10 NUCLEI AS A TEST OF GFMC Ab-INITIO CALCULATIONS". International Journal of Modern Physics E 19, n. 05n06 (giugno 2010): 946–56. http://dx.doi.org/10.1142/s0218301310015394.

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A new generation of self-consistent calculations has deepened our understanding of how nuclei are bound and the structure and spatial extent of their wavefunctions. New methods are being developed to calculate nuclear properties starting from realistic unrenormalized two-body nucleon-nucleon potentials. Higher order correlations are needed to reproduce both masses and spectra, and the special importance of three-body correlations has become clear. Precise experimental measurements can help improve the calculations and constrain the form and strength of three body Hamiltonians. In this contribution, I will review new calculations on A =10 nuclei made with the Greens Function Monte Carlo method (GFMC) using a variety of three-body interactions, and new experiments designed to measure the lifetime of excited states with an improved Doppler Shift Attenuation Method (DSAM*). The electromagnetic matrix elements are determined to a level of precision, <5%, that really challenge GFMC and other contemporary theories.

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Più fonti

Tesi sul tema "Greens function methods"

Orlando, Roberto. "Exploration de nouveaux noyaux d'échange-corrélation dans l'équation de Bethe-Salpeter". Electronic Thesis or Diss., Toulouse 3, 2023. http://www.theses.fr/2023TOU30275.

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Le sujet de thèse porte sur de nouvelles approximations étudiées dans un formalisme basé sur une théorie des perturbations permettant de décrire de manière approchée les propriétés électroniques des systèmes à N corps. On excite un système avec une petite perturbation, en envoyant de la lumière sur celui-ci ou en lui appliquant un faible champ électrique, par exemple et le système "répond" à la perturbation, dans le cadre d'une réponse linéaire, ce qui signifie que la réponse du système Le système est proportionnel à la perturbation. Le but est de déterminer ce que l'on appelle les excitations neutres ou états liés du système, et plus particulièrement les excitations simples. Ceux-ci correspondent aux transitions de l'état fondamental vers un état excité. Pour ce faire, nous décrivons de manière simplifiée les interactions des particules d'un système à N corps en utilisant une interaction effective que nous moyennons sur l'ensemble du système. L'objectif d'une telle approche est de pouvoir étudier un système sans avoir à recourir au formalisme exact qui consiste à diagonaliser l'hamiltonien à N corps, ce qui n'est pas possible pour des système à plus de deux particules
The subject of the thesis focuses on new approximations studied in a formalism based on a perturbation theory allowing to describe the electronic properties of many-body systems in an approximate way. We excite a system with a small disturbance, by sending light on it or by applying a weak electric field to it, for example and the system "responds" to the disturbance, in the framework of linear response, which means that the response of the system is proportional to the disturbance. The goal is to determine what we call the neutral excitations or bound states of the system, and more particularly the single excitations. These correspond to the transitions from the ground state to an excited state. To do this, we describe in a simplified way the interactions of the particles of a many-body system using an effective interaction that we average over the whole system. The objective of such an approach is to be able to study a system without having to use the exact formalism which consists in diagonalizing the N-body Hamiltonian, which is not possible for systems with more than two particles

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Zhang, Bufa. "Optical methods of thermal diffusivity measurement". Thesis, London South Bank University, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336374.

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Teke, Nakul Kushabhau. "Explicitly correlated Green's function methods for calculating electron binding energies". Thesis, Virginia Tech, 2019. http://hdl.handle.net/10919/101962.

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Single-particle Green's function method is a direct way of calculating electron binding energy, which relies on expanding the Fock subspace in a finite single-particle basis. However, these methods suffer from slow asymptotic decay of basis set incompleteness error. An energy-dependent explicitly correlated (F12) formalism for Green's function is presented that achieves faster convergence to the basis set limit. The renormalized second-order Green's function method (NR2-F12) scales as iterative N^5 where N is the system size. These methods are tested on a set of small (O21) and medium-sized (OAM24) organic molecules. The basis set incompleteness error in ionization potential (IP) obtained from the NR2-F12 method and aug-cc-pVDZ basis for OAM24 is 0.033 eV compared to 0.067 eV for NR2 method and aug-cc-pVQZ basis. Hence, accurate electron binding energies can be calculated at a lower cost using NR2-F12 method. For aug-cc-pVDZ basis, the electron binding energies obtained from NR2-F12 are comparable to EOM-IP-CCSD method that uses a CCSD reference and scales as iterative N^6.
Master of Science

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Pavosevic, Fabijan. "Explicitly Correlated Methods for Large Molecular Systems". Diss., Virginia Tech, 2018. http://hdl.handle.net/10919/82000.

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Wave function based electronic structure methods have became a robust and reliable tool for the prediction and interpretation of the results of chemical experiments. However, they suffer from very steep scaling behavior with respect to an increase in the size of the system as well as very slow convergence of the correlation energy with respect to the basis set size. Thus these methods are limited to small systems of up to a dozen atoms. The first of these issues can be efficiently resolved by exploiting the local nature of electron correlation effects while the second problem is alleviated by the use of explicitly correlated R12/F12 methods. Since R12/F12 methods are central to this work, we start by reviewing their modern formulation. Next, we present the explicitly correlated second-order Mo ller-Plesset (MP2-F12) method in which all nontrivial post-mean-field steps are formulated with linear computational complexity in system size [Pavov{s}evi'c et al., {em J. Chem. Phys.} {bf 144}, 144109 (2016)]. The two key ideas are the use of pair-natural orbitals for compact representation of wave function amplitudes and the use of domain approximation to impose the block sparsity. This development utilizes the concepts for sparse representation of tensors described in the context of the DLPNO-MP2 method by Neese, Valeev and co-workers [Pinski et al., {em J. Chem. Phys.} {bf 143}, 034108 (2015)]. Novel developments reported here include the use of domains not only for the projected atomic orbitals, but also for the complementary auxiliary basis set (CABS) used to approximate the three- and four-electron integrals of the F12 theory, and a simplification of the standard B intermediate of the F12 theory that avoids computation of four-index two-electron integrals that involve two CABS indices. For quasi-1-dimensional systems (n-alkanes) the bigO{N} DLPNO-MP2-F12 method becomes less expensive than the conventional bigO{N^{5}} MP2-F12 for $n$ between 10 and 15, for double- and triple-zeta basis sets; for the largest alkane, C$_{200}$H$_{402}$, in def2-TZVP basis the observed computational complexity is $N^{sim1.6}$, largely due to the cubic cost of computing the mean-field operators. The method reproduces the canonical MP2-F12 energy with high precision: 99.9% of the canonical correlation energy is recovered with the default truncation parameters. Although its cost is significantly higher than that of DLPNO-MP2 method, the cost increase is compensated by the great reduction of the basis set error due to explicit correlation. We extend this formalism to develop a linear-scaling coupled-cluster singles and doubles with perturbative inclusion of triples and explicitly correlated geminals [Pavov{s}evi'c et al., {em J. Chem. Phys.} {bf 146}, 174108 (2017)]. Even for conservative truncation levels, the method rapidly reaches near-linear complexity in realistic basis sets; e.g., an effective scaling exponent of 1.49 was obtained for n-alkanes with up to 200 carbon atoms in a def2-TZVP basis set. The robustness of the method is benchmarked against the massively parallel implementation of the conventional explicitly correlated coupled-cluster for a 20-water cluster; the total dissociation energy of the cluster ($sim$186 kcal/mol) is affected by the reduced-scaling approximations by only $sim$0.4 kcal/mol. The reduced-scaling explicitly correlated CCSD(T) method is used to examine the binding energies of several systems in the L7 benchmark data set of noncovalent interactions. Additionally, we discuss a massively parallel implementation of the Laplace transform perturbative triple correction (T) to the DF-CCSD energy within density fitting framework. This work is closely related to the work by Scuseria and co-workers [Constans et al., {em J. Chem. Phys.} {bf 113}, 10451 (2000)]. The accuracy of quadrature with respect to the number of quadrature points has been investigated on systems of the 18-water cluster, uracil dimer and pentacene dimer. In the case of the 18-water cluster, the $mu text{E}_{text{h}}$ accuracy is achieved with only 3 quadrature points. For the uracil dimer and pentacene dimer, 6 or more quadrature points are required to achieve $mu text{E}_{text{h}}$ accuracy; however, binding energy of $<$1 kcal/mol is obtained with 4 quadrature points. We observe an excellent strong scaling behavior on distributed-memory commodity cluster for the 18-water cluster. Furthermore, the Laplace transform formulation of (T) performs faster than the canonical (T) in the case of studied systems. The efficiency of the method has been furthermore tested on a DNA base-pair, a system with more than one thousand basis functions. Lastly, we discuss an explicitly correlated formalism for the second-order single-particle Green's function method (GF2-F12) that does not assume the popular diagonal approximation, and describes the energy dependence of the explicitly correlated terms [Pavov{s}evi'c et al., {em J. Chem. Phys.} {bf 147}, 121101 (2017)]. For small and medium organic molecules the basis set errors of ionization potentials of GF2-F12 are radically improved relative to GF2: the performance of GF2-F12/aug-cc-pVDZ is better than that of GF2/aug-cc-pVQZ, at a significantly lower cost.
Ph. D.

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Sztulzaft, Patrick. "Green-expert : un solveur généralisé associé à un générateur de formulations pour la méthode des intégrales de frontières". Grenoble INPG, 1994. https://hal.archives-ouvertes.fr/tel-01331763.

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De nombreux secteurs de l'industrie et de la recherche utilisent la modélisation des phénomènes de la physique des milieux continus. Les équations aux dérivées partielles décrivant ces phénomènes sont résolues à l'aide de diverses méthodes numériques. Les modélisations utilisées sont de plus en plus pointues, tant au niveau physique qu'au niveau numérique. Les réponses logicielles à ces problèmes doivent donc être évolutives. Ce travail s'insère dans une dynamique de recherche dans le domaine de la modélisation des phénomènes complexes qui a débuté avec l'élaboration du programme Flux-Expert®, basé sur la Méthode des Eléments Finis. Afin d'élargir le champ des possibilités offertes par ce programme, nous avons choisi d'y associer la Méthodes des Intégrales de Frontières. Dans cette optique, après une présentation didactique de la Méthode des Intégrales de Frontières, nous proposons une décomposition générale de la résolution numérique d'un problème à l'aide de cette méthode. Nous décrivons ensuite le logiciel issu de cette analyse : Green-Expert. L'originalité de la démarche réside dans l'association d'un programme Générateur de Formulations et d'un programme Solveur généralisé. Ce Solveur est capable de résoudre tout problème décrit à l'aide d'une formulation issue du Générateur et d'une Géométrie discrétisée. La dernière partie de ce mémoire est consacré à la validation. Des exemples de couplage entre la Méthode des Intégrales de Frontières et la Méthode des Éléments Finis sont présentés. Enfin, des exemples de résolution 2D et 3D permettent de valider le Générateur et le Solveur de Green-Expert
Investigations in many sectors of industry and research require the modelling of phenomena observed in the physics of continuous media. The partial differential equations describing these phenomena are solved using a wide range of numerical methods. The models used are increasingly sophisticated, from both a physical and numerical point of view. Software used to solve these problems must therefore be capable of evolving. This work is a continuation of research efforts devoted to the modelling of complex phenomena that began with the development of the Flux-Expert® program, based on the Finite Element Method. In order to extend the possibilities offered by this program, we decided to combine it with the Boundary Element Method. After reviewing the Boundary Element Method, we propose a general decomposition of the numerical solution of a problem using this method. We then describe the Green-Expert software developed on the basis of this analysis. The original aspect of the approach lies in the combination of a formulations generator and a general solver. This solver is capable of solving any problem described using a formulation coming from the Generator and a discrete geometry. The last part of this thesis is devoted to the validation phase. Examples of the combined use of the Boundary Elements and the Finite Element Methods are presented and examples of 2D and 3D resolution are used to validate the Green-Expert Solver and Generator

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da, Costa Filho Carlos Alberto. "Elastodynamic Green's function retrieval : theory and applications in exploration geophysics". Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/28760.

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The ability to synthesize recordings from surface data as if they had come from subsurface sources has allowed geophysicists to estimate subsurface properties. Either in the form of classical seismic migration which creates structural maps of the subsurface, to the more recent seismic interferometry which turns seismic sources into receivers and vice-versa, this ability has provided a rich trove of methods with which to probe the Earth's interior. While powerful, both of these techniques suffer from well-known issues. Standard migration requires data without multiply-scattered waves (multiples). Seismic interferometry, on the other hand, can be applied to full recorded data (containing multiples and other wave types), but requires sources (receivers) to be physically placed at the location from (to) one wishes to estimate responses. The Marchenko method, developed recently for the seismic setting, circumvents both of these restrictions: it creates responses from virtual subsurface sources as if measured at the surface. It requires only single-sided surface data, and a smooth estimate of the subsurface velocities. Initially developed for acoustic media, this thesis contributes the first elastic formulation of the Marchenko method, providing a more suitable setting for applications for the solid Earth. In another development, this thesis shows how the obtained virtual recordings may be used for migration. With these two contributions, this thesis shows that for elastic surface seismic data, the main drawbacks of migration and interferometry can be overcome using the Marchenko method: multiples do not harm migrated images, and sources (receivers) need not be physically placed in the medium for their responses to be accessible. In addition to the above methods, generating images devoid of multiple-related artifacts can be achieved in several other different ways. Two approaches to this are the use of a post-imaging filter, and attenuation of internal multiples in the data itself. This thesis contributes one new method using each of these approaches. First, a form of Marchenko imaging is known to create spurious reflectors, as also occurs in standard reverse-time migration (RTM). However, these artifacts usually appear at different locations in RTM and this form of Marchenko imaging. Using this insight, this thesis presents a way to combine pairs of seismic images in such a way that their differences (e.g. artifacts) are attenuated, while similarities (e.g. true reflectors) are preserved. Applying this to RTM and Marchenko-derived images markedly improves image quality. Second, this thesis presents a method to estimate multiples in the data. Multiples can either be migrated on their own to aid in interpretation, or be adaptatively removed from the data to improve image quality. However, because of the nature of adaptive subtraction, this second method may harm primary energy. To avoid this problem, this thesis develops a final method to directly image using only primary energy in the recorded data using only a small number of virtual points. This method bypasses the need for multiple removal and the estimation of subsurface responses at every depth location. In addition, primaries from particular reflectors may be particularly selected such that they can be imaged individually. Overall this thesis provides several new ways to use surface seismic data in such a way that multiples do not hamper the end product of seismic data processing: the seismic image. It demonstrates this use on synthetic and real data, proving their effectiveness.

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Yeo, Stephen K. N. "Generalised periodic Green's function analysis of microstrip dipole arrays /". Title page, contents and abstract only, 1996. http://web4.library.adelaide.edu.au/theses/09PH/09phy46.pdf.

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Kogan, V. R. "Method of quasiclassical green function in different problems of mesoscopic physics". [S.l.] : [s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968833500.

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Toson, Valentina. "Preparation of functional nanostructured materials by facile and green methods". Doctoral thesis, Università del Piemonte Orientale, 2018. http://hdl.handle.net/11579/97205.

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A challenging goal of Chemistry is its sustainability towards a circular no-waste approach. This statement has been the mainstream of this PhD work, applied to innovative functional materials based on inorganic hosting substrates. The experimental work has used synthetic strategies, optimization tools and characterization methods to identify and pursue materials with facile, rapid and green preparations for functional photoactive materials, improving durability and performances. A part of the work dealt with the study and optimization of the preparation of tailored inorganic hosts, as synthetic layered clay-like materials (saponite), with a study of the synthetic conditions and the thermal treatment features to achieve high yield, morphological and compositional quality with a reduced energetic payload. Aside, in a waste-reduction strategy, a highly innovative approach was carried on using biomasses (i.e. rice husk and straw) as sources of inorganics for materials with controlled composition. The preparation of functional materials via host-guest architectures was targeted on photoactive systems using anionic (i.e. DyeA) and neutral (GAM2-35) photoactive dyes, to be incorporated in hydrotalcite and synthetic saponite clay respectively. A mechanochemical methodology of intercalation of DyeA into hydrotalcite based on the Liquid Assisted Grinding (LAG) was fully optimized using statistical tools as factorial design and Simplex. Intercalating neutral optically active dyes in saponite was then pursued using a quasi-solid state co-intercalation of GAM2-35 and a proper cationic surfactant (CTAB), avoiding the use of harsh conditions of temperature and pH. To fulfill an approach to sustainable hotoactive host-guest materials, a full asset of high throughput characterization techniques, as in situ XRPD and Uv-Vis methods and chemometric methodologies, was applied to an established fully thermal process coming from the past, the Maya Blue formation from palygorskite and indigo.

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Tanaka, Y., Y. Tanuma e A. A. Golubov. "Odd-frequency pairing in normal-metal/superconductor junctions". American Physical Society, 2007. http://hdl.handle.net/2237/11289.

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Più fonti

Libri sul tema "Greens function methods"

W, Wilson J., e United States. National Aeronautics and Space Administration. Scientific and Technical Information Program., a cura di. Green's function methods in heavy ion shielding. [Washington, DC]: National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Program, 1993.

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W, Wilson John. Green's function methods in heavy ion shielding. Hampton, Va: Langley Research Center, 1993.

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Søndergaard, Thomas M. Green’s Function Integral Equation Methods in Nano-Optics. First edition. | Boca Raton, FL : CRC Press/Taylor & Francis Group, 2019.: CRC Press, 2019. http://dx.doi.org/10.1201/9781351260206.

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Wilson, John W. Approximate Green's function methods for HZE transport in multilayered materials. Hampton, Va: Langley Research Center, 1993.

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W, Wilson J., e United States. National Aeronautics and Space Administration. Scientific and Technical Information Program., a cura di. Approximate Green's function methods for HZE transport in multilayered materials. [Washington, DC]: National Aeronautics and Space Administration, Office of Management, Scientific and Technical Information Program, 1993.

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Kadanoff, Leo P. Quantum statistical mechanics: Green's function methods in equilibrium and nonequilibrium problems. Redwood City, Calif: Addison-Wesley Pub. Co., Advanced Book Program, 1989.

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Helszajn, J. Green's function, finite elements, and microwave planar circuits. Chichester: J. Wiley, 1996.

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Pourfath, Mahdi. The Non-Equilibrium Green's Function Method for Nanoscale Device Simulation. Vienna: Springer Vienna, 2014. http://dx.doi.org/10.1007/978-3-7091-1800-9.

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Hartmann, Friedel. Green's Functions and Finite Elements. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013.

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Johnston, Janet C. Simulating a large Wasatch Front, Utah, earthquake using small earthquake recordings as Green's functions. Hanscom AFB, MA: Earth Sciences Division, Air Force Geophysics Laboratory, 1986.

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Capitoli di libri sul tema "Greens function methods"

el Moctar, Bettar Ould, Thomas E. Schellin e Heinrich Söding. "Green Function Methods". In Numerical Methods for Seakeeping Problems, 87–95. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-62561-0_6.

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Chau, K. T. "Green’s Function Method". In Theory of Differential Equations in Engineering and Mechanics, 493–538. Boca Raton : CRC Press, [2017]: CRC Press, 2017. http://dx.doi.org/10.1201/9781315164939-8.

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Turek, Ilja, Václav Drchal, Josef Kudrnovský, Mojmír Šob e Peter Weinberger. "Green Function Method". In Electronic Structure of Disordered Alloys, Surfaces and Interfaces, 59–112. Boston, MA: Springer US, 1997. http://dx.doi.org/10.1007/978-1-4615-6255-9_3.

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Artemyev, Anton N. "Two-Time Greens Function Method". In Handbook of Relativistic Quantum Chemistry, 287–312. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-642-40766-6_28.

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Wells, B. H. "Green’s Function Monte Carlo Methods". In Methods in Computational Chemistry, 311–50. Boston, MA: Springer US, 1987. http://dx.doi.org/10.1007/978-1-4899-1983-0_4.

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Iwaniec, Henryk. "The automorphic Green function". In Spectral Methods of Automorphic Forms, 71–79. Providence, Rhode Island: American Mathematical Society, 2002. http://dx.doi.org/10.1090/gsm/053/07.

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Aliev, Farkhad G., e Antonio Lara. "Harmonic Oscillator and Green's Function". In Mathematical Methods for Physics, 1–24. New York: Jenny Stanford Publishing, 2023. http://dx.doi.org/10.1201/9781003410881-1.

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Søndergaard, Thomas. "Green’s Function Integral Equation Method". In Encyclopedia of Nanotechnology, 1–9. Dordrecht: Springer Netherlands, 2016. http://dx.doi.org/10.1007/978-94-007-6178-0_18-2.

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Søndergaard, Thomas. "Green’s Function Integral Equation Method". In Encyclopedia of Nanotechnology, 1381–88. Dordrecht: Springer Netherlands, 2016. http://dx.doi.org/10.1007/978-94-017-9780-1_18.

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Artemyev, Anton N. "Two-Time Green’s Function Method". In Handbook of Relativistic Quantum Chemistry, 1–26. Berlin, Heidelberg: Springer Berlin Heidelberg, 2016. http://dx.doi.org/10.1007/978-3-642-41611-8_28-1.

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Atti di convegni sul tema "Greens function methods"

Sondergaard, Thomas, Mads Brincker e Esben Skovsen. "Theoretical analysis of microstructured gradient-index lens for THz photonics using Greens function integral equation methods". In 2016 41st International Conference on Infrared, Millimeter, and Terahertz waves (IRMMW-THz). IEEE, 2016. http://dx.doi.org/10.1109/irmmw-thz.2016.7758624.

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Cuadrado, David G., Francisco Lozano, Valeria Andreoli e Guillermo Paniagua. "Engine-Scalable Rotor Casing Convective Heat Flux Evaluation Using Inverse Heat Transfer Methods". In ASME Turbo Expo 2018: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/gt2018-76906.

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In this paper, we propose a two-step methodology to evaluate the convective heat flux along the rotor casing using an engine-scalable approach based on Discrete Green’s Functions. The first step consists in the use of an inverse heat transfer technique to retrieve the heat flux distribution on the shroud inner wall by measuring the temperature of the outside wall; the second step is the calculation of the convective heat flux at engine conditions, using the experimental heat flux and the Green Functions engine-scalable technique. Inverse methodologies allow the determination of boundary conditions, in this case the inner casing surface heat flux, based on measurements from outside of the system, which prevents aerothermal distortion caused by routing the instrumentation into the test article. The heat flux, retrieved from the inverse heat transfer methodology, is related to the rotor tip gap. Therefore, for a given geometry and tip gap, the pressure and temperature can also be retrieved. In this work, the Digital Filter Method is applied in order to take advantage of the response of the temperature to heat flux pulses. The Discrete Green’s Function approach employs a matrix to relate an arbitrary temperature distribution to a series of pulses of heat flux. In the present procedure, the terms of the Green’s Function matrix are evaluated with the output of the inverse heat transfer method. Given that key dimensionless numbers are conserved, the Green’s Functions matrix can be extrapolated to engine-like conditions. A validation of the methodology is performed by imposing different arbitrary heat flux distributions, to finally demonstrate the scalability of the Green’s Function Method to engine conditions. A detailed uncertainty analysis of the two-step routine is included based on the value of the pulse of heat flux, the temperature measurement uncertainty, the thermal properties of the material and the physical properties of the rotor casing.

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Liao, Tien-Hao, Kung-Hau Ding e Leung Tsang. "Green's function in waveguides with inhomogeneous dielectrics using the method of broadband green's functions". In 2017 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting. IEEE, 2017. http://dx.doi.org/10.1109/apusncursinrsm.2017.8072528.

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Galperin, Misha. "Green Function Methods for Optoelectronics". In 2019 URSI International Symposium on Electromagnetic Theory (EMTS). IEEE, 2019. http://dx.doi.org/10.23919/ursi-emts.2019.8931556.

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Lueschen, Gerhard G. G., e Lawrence A. Bergman. "Green’s Function Synthesis for Layered Distributed Parameter Systems". In ASME 1995 Design Engineering Technical Conferences collocated with the ASME 1995 15th International Computers in Engineering Conference and the ASME 1995 9th Annual Engineering Database Symposium. American Society of Mechanical Engineers, 1995. http://dx.doi.org/10.1115/detc1995-0650.

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Abstract Dynamic Green’s functions for a class of layered distributed parameter systems are derived using a new method. The resulting system Green’s function, which is comprised of the elemental Green’s function of each of the substructures, defines the dynamics of the fully coupled system. Green’s functions for sandwiched beams with both identical and different layer properties are derived. The result retains the accuracy of the constituent elemental Green’s functions. The application of the method to other layered structures is immediate as long as the elemental Green’s functions of the substructures are known.

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Nerukh, A., e D. Zolotariov. "Green's function for paraxial equation in time domain". In 2012 International Conference on Mathematical Methods in Electromagnetic Theory (MMET). IEEE, 2012. http://dx.doi.org/10.1109/mmet.2012.6331276.

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Ganesa-Pillai, Madhu, e A. Haji-Sheikh. "A Critical Evaluation of the Monte Carlo Method for Application to the Inverse Heat Conduction Problem". In ASME 1998 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 1998. http://dx.doi.org/10.1115/imece1998-0726.

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Abstract The solutions of the Inverse Heat Conduction Problem using the Monte Carlo method, Green’s Function Solution Equation and the Alternative Green’s Function Solution Equation are compared. The Monte Carlo method is a simple technique that provides a method of determining the source of error and placement of sensors. However, in comparison with the exact solution, if attainable, the cost is a higher error in the solution. All the three methods use the function specification method in the sense that a functional form for the surface heat flux or temperature is assumed and the parameters defining the function are evaluated by minimizing the error functional. In the alternative method, the functional form also satisfies the boundary conditions, the unknown quantity in the problem. The input data for this comparison are experimentally measured temperatures in a stainless steel disk subjected to spray cooling.

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Gomes do Nascimento, Jefferson, José Ricardo Ferreira Oliveira, José Aguiar santos junior, Guilherme Ramalho Costa e Gilmar Guimaraes. "Heat Flow Estimation Using Sequential Method and Transfer Function Based on Green's Functions". In 25th International Congress of Mechanical Engineering. ABCM, 2019. http://dx.doi.org/10.26678/abcm.cobem2019.cob2019-2356.

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Sousa, Priscila F. B., Ana P. Fernandes, Vale´rio Luiz Borges, George S. Dulikravich e Gilmar Guimara˜es. "Dynamic Observer Method Based on Modified Green’s Functions for Robust and More Stable Inverse Algorithms". In ASME 2008 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/detc2008-49062.

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This work presents a modified procedure to use the concept of dynamic observers based on Green’s functions to solve inverse problems. The original method can be divided in two distinct steps: i) obtaining a transfer function model GH and; ii) obtaining heat transfer functions GQ and GN and building an identification algorithm. The transfer function model, GH, is obtained from the equivalent dynamic systems theory using Green’s functions. The modification presented here proposes two different improvements in the original technique: i) A different method of obtaining the transfer function model, GH, using analytical functions instead of numerical procedures, and ii) Definition of a new concept of GH to allow the use of more than one response temperature. Obtaining the heat transfer functions represents an important role in the observer method and is crucial to allow the technique to be directly applied to two or three-dimensional heat conduction problems. The idea of defining the new GH function is to improve the robustness and stability of the algorithm. A new dynamic equivalent system for the thermal model is then defined in order to allow the use of two or more temperature measurements. Heat transfer function, GH can be obtained numerically or analytically using Green’s function method. The great advantage of deriving GH analytically is to simplify the procedure and minimize the estimative errors.

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STAMATAKOS, GEORGIOS S., KONSTANTINA S. NIKITA, NIKOLAOS K. UZUNOGLU e AGGELOS KARAFOTIAS. "THE GREEN'S FUNCTION/METHOD OF AUXILIARY SOURCES TECHNIQUE (GREEN/MAS): APPLICATION TO MOBILE PHONE DOSIMETRY". In Proceedings of the 4th International Workshop. WORLD SCIENTIFIC, 2000. http://dx.doi.org/10.1142/9789812792327_0018.

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Rapporti di organizzazioni sul tema "Greens function methods"

Lin, Lin. Green's function methods for multiphysics simulations. Office of Scientific and Technical Information (OSTI), ottobre 2023. http://dx.doi.org/10.2172/2202484.

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Brandl, Maria T., Shlomo Sela, Craig T. Parker e Victor Rodov. Salmonella enterica Interactions with Fresh Produce. United States Department of Agriculture, settembre 2010. http://dx.doi.org/10.32747/2010.7592642.bard.

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The emergence of food-borne illness outbreaks linked to the contamination of fruits and vegetables is a great concern in industrialized countries. The current lack of control measures and effective sanitization methods prompt the need for new strategies to reduce contamination of produce. Our ability to assess the risk associated with produce contamination and to devise innovative control strategies depends on the identification of critical determinants that affect the growth and the persistence of human pathogens on plants. Salmonella enterica, a common causal agent of illness linked to produce, has the ability to colonize and persist on plants. Thus, our main objective was to identify plant-inducible genes that have a role in the growth and/or persistence of S. enterica on postharvest lettuce. Our findings suggest that in-vitro biofilm formation tests may provide a suitable model to predict the initial attachment of Salmonella to cut-romaine lettuce leaves and confirm that Salmonella could persist on lettuce during shelf-life storage. Importantly, we found that Salmonella association with lettuce increases its acid-tolerance, a trait which might be correlated with an enhanced ability of the pathogen to pass through the acidic barrier of the stomach. We have demonstrated that Salmonella can internalize leaves of iceberg lettuce through open stomata. We found for the first time that internalization is an active bacterial process mediated by chemotaxis and motility toward nutrient produced in the leaf by photosynthesis. These findings may provide a partial explanation for the failure of sanitizers to efficiently eradicate foodborne pathogens in leafy greens and may point to a novel mechanism utilized by foodborne and perhaps plant pathogens to colonize leaves. Using resolvase in vivo expression technology (RIVET) we have managed to identify multiple Salmonella genes, some of which with no assigned function, which are involved in attachment to and persistence of Salmonella on lettuce leaves. The precise function of these genes in Salmonella-leaf interactions is yet to be elucidated. Taken together, our findings have advanced the understanding of how Salmonella persist in the plant environment, as well as the potential consequences upon ingestion by human. The emerging knowledge opens new research directions which should ultimately be useful in developing new strategies and approaches to reduce leaf contamination and enhance the safety of fresh produce.

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Poppeliers, Christian, e Leiph Preston. An efficient method to estimate the probability density of seismic Green's functions. Office of Scientific and Technical Information (OSTI), agosto 2021. http://dx.doi.org/10.2172/1813651.

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Stocks, G. M. (The use of parallel computers and multiple scattering Green function methods in condensed matter physics). Office of Scientific and Technical Information (OSTI), novembre 1990. http://dx.doi.org/10.2172/6352675.

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A.A. Bingham, R.M. Ferrer e A.M. ougouag. Nodal Green?s Function Method Singular Source Term and Burnable Poison Treatment in Hexagonal Geometry. Office of Scientific and Technical Information (OSTI), settembre 2009. http://dx.doi.org/10.2172/983357.

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Branch, Darren W. Hybrid method for the precise calculation of the general dyadic Greens functions for SAW and leaky wave substrates. Office of Scientific and Technical Information (OSTI), maggio 2008. http://dx.doi.org/10.2172/942184.

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Cranfield, John, Paul Preckel e Thomas Hertel. Poverty Analysis Using an International Cross-Country Demand System. GTAP Working Paper, novembre 2006. http://dx.doi.org/10.21642/gtap.wp34.

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This paper proposes a new method for ex ante analysis of the poverty impacts arising from policy reforms. Three innovations underlie this approach. The first is the estimation of a global demand system using a combination of micro-data from household surveys, and macro-data from the International Comparisons Project. Estimation is undertaken in a manner that reconciles these two sources of information, explicitly recognizing that per capita national demands are an aggregation of the disaggregated, individual household demands. The second innovation relates to a methodology for post-estimation calibration of the global demand system, giving rise to country specific demand systems and an associated expenditure function which, when aggregated across the expenditure distribution, reproduce observed per capita budget shares exactly. The third innovation is use of the calibrated expenditure function to calculate the change in the head-count of poverty, poverty gap and squared poverty gap arising from policy reforms, where the poverty measures are derived using a unique poverty level of utility, rather than an income or expenditure-based measure. We employ these techniques with a demand system for food, other non-durables and services estimated using a combination of 1996 ICP data set and national expenditure distribution data. Calibration is demonstrated for three countries for which household survey expenditure data are utilized during estimation; namely, Indonesia, the Philippines and Thailand. To illustrate the usefulness of these calibrated models for policy analysis, we assess the impacts of an assumed five percent food price rise as might be realized in the wake of a multilateral trade agreement. Results illustrate the important role of subsistence expenditures at low per capita income levels, but of discretionary expenditure at higher per capita income levels. The welfare analysis underscores the relatively large impact of the price hike on poorer households, while a modified Foster-Greer-Thorbecke poverty measure shows that the five percent price rise has a differential effect on poverty across the three focus countries, although it increases the incidence and intensity of poverty in all three cases.

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Morin, S., L. L. Walling, Peter W. Atkinson, J. Li e B. E. Tabashnik. ets for CRISPR/Cas9-mediated gene drive in Bemisia tabaci. Israel: United States-Israel Binational Agricultural Research and Development Fund, 2021. http://dx.doi.org/10.32747/2021.8134170.bard.

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The goal of our BARD proposal was to build both the necessary infrastructure and knowledge for using the CRISPR/Cas9-based gene drive system to control the whitefly Bemisia tabaci. Our research focused on achieving three main goals: (1) establishing a CRISPR/Cas9 gene-editing system for producing genetically-edited B. tabaci; (2) generating and testing CRISPR/Cas9-mediated mutations targeting genes that represent two gene drive strategies: population replacement and population suppression; (3) using computer modeling to optimize strategies for applying CRISPR/Cas9 to control B. tabaci populations in the field. CRISPR gene drive is one of the most promising strategies for diminishing the negative impacts of harmful insects. This technique can introduce mutations into wild populations of pests that reduce their ability to cause damage, reduce their population size, or both. In principle, this can be selfsustaining because mutations carried by relatively few insects can increase in frequency and spread quickly throughout wild populations. Because of this sustainability and the potential benefits to society, agricultural gene-drive systems are most likely to be funded by government agencies, foundations, and grower associations; as with sterile insect releases and most biocontrol programs. Although gene drives have received intensive study in Drosophila and mosquito vectors of human disease, we were one of the first teams pursuing this approach for crop pests. Our project was also one of the first to address CRISPR gene drive in the Hemiptera, an insect order that includes hundreds of pest species. We focused on developing and implementing CRISPR gene drive to reduce the massive damage caused by B. tabaci. This haplodiploid insect is one of the world's most devastating crop pests. Whereas extensive work by others explored CRISPR in diploid species, our project pioneered application of this revolutionary technology to haplodiploids, which have a distinct system of inheritance that presents special challenges and opportunities. Our project has achieved several breakthroughs, including publication of the first paper analyzing CRISPR gene drive in haplodiploids (Li et al. 2020, see next section). Our modeling results from this landmark study demonstrate that CRISPR gene drive can work in haplodiploids, especially if fitness costs associated with the driver allele are low or nil. Our paper was the first to provide a conceptual framework for evaluating and optimizing CRISPR gene drive strategies for managing B. tabaci and other haplodiploid pests. Our breakthroughs in the laboratory have created the infrastructure needed to develop CRISPR for controlling B. tabaci. We established a microinjection system enabling us to introduce CRISPR-derived mutations into B. tabaci embryos. We have used this system to generate and track inherited eye-color mutants of B. tabaci. We have identified and cloned germline promoters, and demonstrated their function in transgenic B. tabaci embryos and other hemipteran insects. We have also developed a tool to easily identify B. tabaci harboring CRISPR-mediated mutations by tagging target genes using a transgenic fluorescent marker. The successful completion of our project provides all the knowledge and infrastructure essential for developing a novel genetic approach for B. tabaci control, which can serve as a non-chemical "green" alternative for managing this global pest. We predict that our discoveries will accelerate the development of the CRISPR gene drive technique for reducing the numbers of this pest and the damage it causes. Still, realization of the benefits of gene-drive technology for pest control will require sustained attention to potential environmental and societal impacts, as well as regulatory and implementation challenges. Given the great promise of this technology and the urgent need for better control methods, we expect that guidance documents and regulations will be in place to allow the scientific community to safely move gene drives for pest control from the laboratory to field trials.

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