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Littérature scientifique sur le sujet « One-Parameter group of transformation »

Auteur : Grafiati
Publié le 1 février 2025

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Articles de revues sur le sujet "One-Parameter group of transformation"

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Al-Shomrani, M. M. « Lie Groups Analysis and Contact Transformations for Ito System ». Abstract and Applied Analysis 2012 (2012) : 1–12. http://dx.doi.org/10.1155/2012/342680.

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Generalized Ito systems of four coupled nonlinear evaluation equations are proposed. New classes of exact invariant solutions by using Lie group analysis are obtained. Moreover, we investigate the existence of a one-parameter group of contact transformations for a generalized Ito system. Consequently, we study the relationship between one-parameter group of a contact transformation and a one-parameter Lie point transformation for a generalized Ito system.
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Cieśliński, Jan L., et Dzianis Zhalukevich. « Spectral Parameter as a Group Parameter ». Symmetry 14, no 12 (6 décembre 2022) : 2577. http://dx.doi.org/10.3390/sym14122577.

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A large class of integrable non-linear partial differential equations is characterized by the existence of the associated linear problem (in the case of two independent variables, known as a Lax pair) containing the so-called spectral parameter. In this paper, we present and discuss the conjecture that the spectral parameter can be interpreted as the parameter of some one-parameter groups of transformation, provided that it cannot be removed by any gauge transformation. If a non-parametric linear problem for a non-linear system is known (e.g., the Gauss–Weingarten equations as a linear problem for the Gauss–Codazzi equations in the geometry of submanifolds), then, by comparing both symmetry groups, we can find or indicate the integrable cases. We consider both conventional Lie point symmetries and the so-called extended Lie point symmetries, which are necessary in some cases. This paper is intended to be a review, but some novel results are presented as well.
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Levi, Inessa. « Group closures of one-to-one transformations ». Bulletin of the Australian Mathematical Society 64, no 2 (octobre 2001) : 177–88. http://dx.doi.org/10.1017/s000497270003985x.

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For a semigroup S of transformations of an infinite set X let Gs be the group of all the permutations of X that preserve S under conjugation. Fix a permutation group H on X and a transformation f of X, and let 〈f: H〉 = 〈{hfh−1: h ∈ H}〉 be the H-closure of f. We find necessary and sufficient conditions on a one-to-one transformation f and a normal subgroup H of the symmetric group on X to satisfy G〈f:H〉 = H. We also show that if S is a semigroup of one-to-one transformations of X and GS contains the alternating group on X then Aut(S) = Inn(S) ≅ GS.
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Polikanova, I. V. « Measuring the arcs of the orbit of a one-parameter transformation group ». Sibirskie Elektronnye Matematicheskie Izvestiya 17 (12 novembre 2020) : 1823–48. http://dx.doi.org/10.33048/semi.2020.17.124.

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Xue-zi, Xu, et Chen Huai-yong. « Application of one-parameter groups of transformation in mechanics ». Applied Mathematics and Mechanics 11, no 7 (juillet 1990) : 679–86. http://dx.doi.org/10.1007/bf02017483.

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Drozhzhinov, Yu N., et B. I. Zav’yalov. « Asymptotically homogeneous generalized functions along trajectories defined by a general one-parameter transformation group ». Doklady Mathematics 82, no 3 (décembre 2010) : 874–77. http://dx.doi.org/10.1134/s1064562410060098.

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Liu, Ping, Senyue Lou et Lei Peng. « Second-Order Approximate Equations of the Large-Scale Atmospheric Motion Equations and Symmetry Analysis for the Basic Equations of Atmospheric Motion ». Symmetry 14, no 8 (27 juillet 2022) : 1540. http://dx.doi.org/10.3390/sym14081540.

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In this paper, symmetry properties of the basic equations of atmospheric motion are proposed. The results on symmetries show that the basic equations of atmospheric motion are invariant under space-time translation transformation, Galilean translation transformations and scaling transformations. Eight one-parameter invariant subgroups and eight one-parameter group invariant solutions are demonstrated. Three types of nontrivial similarity solutions and group invariants are proposed. With the help of perturbation method, we derive the second-order approximate equations for the large-scale atmospheric motion equations, including the non-dimensional equations and the dimensional equations. The second-order approximate equations of the large-scale atmospheric motion equations not only show the characteristics of physical quantities changing with time, but also describe the characteristics of large-scale atmospheric vertical motion.
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Kulish, P. P. « A two-parameter quantum group and a gauge transformation ». Journal of Mathematical Sciences 68, no 2 (janvier 1994) : 220–22. http://dx.doi.org/10.1007/bf01249335.

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Shilin, I. A., et Junesang Choi. « Concerning Transformations of Bases Associated with Unimodular diag(1, −1, −1)-Matrices ». Axioms 13, no 7 (4 juillet 2024) : 452. http://dx.doi.org/10.3390/axioms13070452.

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Considering a representation space for a group of unimodular diag(1, −1, −1)-matrices, we construct several bases whose elements are eigenfunctions of Casimir infinitesimal operators related to a reduction in the group to some one-parameter subgroups. Finding the kernels of base transformation integral operators in terms of special functions, we consider the compositions of some of these transformations. Since composition is a ‘closed’ operation on the set of base transformations, we obtain some integral relations for the special functions involved in the above kernels.
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Abd-el-Malek, Mina B., et Medhat M. Helala. « Steady Flow of an Electrically Conducting Incompressible Viscoelastic Fluid over a Heated Plate ». Zeitschrift für Naturforschung A 60, no 1-2 (1 février 2005) : 29–36. http://dx.doi.org/10.1515/zna-2005-1-205.

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The transformation group theoretic approach is applied to the problem of the flow of an electrically conducting incompressible viscoelastic fluid near the forward stagnation point of a heated plate. The application of one-parameter transformation group reduces the number of independent variables, by one, and consequently the basic equations governing flow and heat transfer are reduced to a set of ordinary differential equations. These equations have been solved approximately subject to the relevant boundary conditions by employing the shooting numerical technique. The effect of the magnetic parameter M, the Prandtl number Pr and the non-dimensional elastic parameter representing the non- Newtonian character of the fluid k on velocity field, shear stress, temperature distribution and heat flux are carefully examined.
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Thèses sur le sujet "One-Parameter group of transformation"

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Morris, Owen Christopher. « On a class of one-parameter operator semigroups with state space Rn x Zm generated by pseudo-differential operators ». Thesis, Swansea University, 2013. https://cronfa.swan.ac.uk/Record/cronfa42779.

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The thesis shows that, under suitable conditions, a pseudo-differential operator, defined on some "nice" set of functions on Rn x Zm, with continuous negative definite symbol q(x,xi,o) extends to a generator of a Feller semigroup. Sections 1-5 are the preliminary sections, these sections discuss some harmonic analysis concerning locally compact Abelian groups. The essence of this thesis are Sections 6-13, which deals with obtaining the estimates required for the fulfilment of the conditions of the Hille-Yosida-Ray theorem.
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Andersson, Ole. « One-parameter Subgroups of the Holomorphic Overshear Group on C2 ». Thesis, Uppsala University, Department of Mathematics, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-122456.

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Ouknine, Anas. « Μοdèles affines généralisées et symétries d'équatiοns aux dérivés partielles ». Electronic Thesis or Diss., Normandie, 2024. http://www.theses.fr/2024NORMR085.

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Cette thèse se consacre à étudier les symétries de Lie d'une classe particulière d'équations différentielles partielles (EDP), désignée sous le nom d'équation de Kolmogorov rétrograde. Cette équation joue un rôle essentiel dans le cadre des modèles financiers, notamment en lien avec le modèle de Longstaff-Schwartz, qui est largement utilisé pour la valorisation des options et des produits dérivés.Dans un contexte plus générale, notre étude s'oriente vers l'analyse des symétries de Lie de l'équation de Kolmogorov rétrograde, en introduisant un terme non linéaire. Cette généralisation est significative, car l'équation ainsi modifiée est liée à une équation différentielle stochastique rétrograde et progressive (EDSRP) via la formule de Feynman-Kac généralisée (non linéaire). Nous nous intéressons également à l'exploration des symétries de cette équation stochastique, ainsi qu'à la manière dont les symétries de l'EDP sont connectées à celles de l'EDSRP.Enfin, nous proposons un recalcul des symétries de l'équation différentielle stochastique rétrograde (EDSR) et de l'EDSRP, en adoptant une nouvelle approche. Cette approche se distingue par le fait que le groupe de symétries qui opère sur le temps dépend lui-même du processus $Y$, qui constitue la solution de l'EDSR. Cette dépendance ouvre de nouvelles perspectives sur l'interaction entre les symétries temporelles et les solutions des équations
This thesis is dedicated to studying the Lie symmetries of a particular class of partialdifferential equations (PDEs), known as the backward Kolmogorov equation. This equa-tion plays a crucial role in financial modeling, particularly in relation to the Longstaff-Schwartz model, which is widely used for pricing options and derivatives.In a broader context, our study focuses on analyzing the Lie symmetries of thebackward Kolmogorov equation by introducing a nonlinear term. This generalization issignificant, as the modified equation is linked to a forward backward stochastic differ-ential equation (FBSDE) through the generalized (nonlinear) Feynman-Kac formula.We also examine the symmetries of this stochastic equation and how the symmetriesof the PDE are connected to those of the BSDE.Finally, we propose a recalculation of the symmetries of the BSDE and FBSDE,adopting a new approach. This approach is distinguished by the fact that the symme-try group acting on time itself depends also on the process Y , which is the solutionof the BSDE. This dependence opens up new perspectives on the interaction betweentemporal symmetries and the solutions of the equations
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Adams, Conny Molatlhegi. « A Lie symmetry analysis of the heat equation through modified one-parameter local point transformation ». Diss., 2014. http://hdl.handle.net/10500/18414.

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Using a Lie symmetry group generator and a generalized form of Manale's formula for solving second order ordinary di erential equations, we determine new symmetries for the one and two dimensional heat equations, leading to new solutions. As an application, we test a formula resulting from this approach on thin plate heat conduction.
Applied Mathematics
M.Sc. (Applied Mathematics)
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Masebe, Tshidiso Phanuel. « A Lie symmetry analysis of the Black-scholes Merton finance model through modified local one-parameter transformations ». Thesis, 2014. http://hdl.handle.net/10500/18410.

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The thesis presents a new method of Symmetry Analysis of the Black-Scholes Merton Finance Model through modi ed Local one-parameter transformations. We determine the symmetries of both the one-dimensional and two-dimensional Black-Scholes equations through a method that involves the limit of in nitesimal ! as it approaches zero. The method is dealt with extensively in [23]. We further determine an invariant solution using one of the symmetries in each case. We determine the transformation of the Black-Scholes equation to heat equation through Lie equivalence transformations. Further applications where the method is successfully applied include working out symmetries of both a Gaussian type partial di erential equation and that of a di erential equation model of epidemiology of HIV and AIDS. We use the new method to determine the symmetries and calculate invariant solutions for operators providing them.
Mathematical Sciences
Applied Mathematics
D. Phil. (Applied Mathematics)
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Livres sur le sujet "One-Parameter group of transformation"

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Dubanov, Aleksandr. Computer simulation in pursuit problems. ru : Publishing Center RIOR, 2022. http://dx.doi.org/10.29039/02102-6.

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Currently, computer simulation in virtual reality systems has a special status. In order for a computer model to meet the requirements of the tasks it models, it is necessary that the mathematical apparatus correctly describe the simulated phenomena. In this monograph, the simulation of pursuit problems is carried out. An adaptive modeling of the behavior of both pursuers and targets is carried out. An iterative calculation of the trajectories of the participants in the pursuit problem is carried out. The main attention is paid to the methods of pursuit and parallel rendezvous. These methods are taken as the basis of the study and are modified in the future. The scientific novelty of the study is the iterative calculation of the trajectories of the participants in the pursuit task when moving at a constant speed, while following the predicted trajectories. The predicted trajectories form a one-parameter network of continuous lines of the first order of smoothness. The predicted trajectories are calculated taking into account the restrictions on the curvature of the participant in the pursuit problem. The fact of restrictions on curvature can be interpreted as restrictions on the angular frequency of rotation of the object of the pursuit problem. Also, the novelty is the calculation of the iterative process of group pursuit of multiple targets, when targets are hit simultaneously or at specified intervals. The calculation of the parameters of the network of predicted trajectories is carried out with a curvature variation in order to achieve the desired temporal effect. The work also simulates the adaptive behavior of the pursuer and the target. The principle of behavior can be expressed on the example of a pursuer with a simple phrase: "You go to the left - I go to the left." This happens at each iteration step in terms of choosing the direction of rotation. For the purpose, the principle of adaptive behavior is expressed by the phrase: "You go to the left - I go to the right." The studies, algorithms and models presented in the monograph can be in demand in the design of autonomously controlled unmanned aerial vehicles with elements of artificial intelligence. The task models in the monograph are supplemented with many animated images, where you can see the research process. Also, the tasks have an implementation in a computer mathematics system and can be transferred to virtual reality systems if necessary.
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Moody, Christopher J. Synthesis : Carbon with Two Attached Heteroatoms with at Least One Carbon-to-Heteroatom Multiple Link, Volume Volume 5 (Comprehensive Organic Functional Group Transformations). Pergamon, 2003.

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Page, James Morris. Ordinary Differential Equations, with an Introduction to Lie's Theory of the Group of One Parameter. Franklin Classics Trade Press, 2018.

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Ordinary Differential Equations, with an Introduction to Lie's Theory of the Group of One Parameter. Creative Media Partners, LLC, 2018.

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Ordinary Differential Equations, with an Introduction to Lie's Theory of the Group of One Parameter. Creative Media Partners, LLC, 2023.

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Page, James Morris. Ordinary Differential Equations, with an Introduction to Lie's Theory of the Group of One Parameter. Franklin Classics Trade Press, 2018.

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Ordinary Differential Equations, with an Introduction to Lie's Theory of the Group of One Parameter. Creative Media Partners, LLC, 2018.

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Page, James Morris. Ordinary Differential Equations : An Elementary Text-Book : With an Introduction to Lie's Theory of the Group of One Parameter. Creative Media Partners, LLC, 2018.

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Tretkoff, Paula. Riemann Surfaces, Coverings, and Hypergeometric Functions. Princeton University Press, 2017. http://dx.doi.org/10.23943/princeton/9780691144771.003.0003.

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This chapter deals with Riemann surfaces, coverings, and hypergeometric functions. It first considers the genus and Euler number of a Riemann surface before discussing Möbius transformations and notes that an automorphism of a Riemann surface is a biholomorphic map of the Riemann surface onto itself. It then describes a Riemannian metric and the Gauss-Bonnet theorem, which can be interpreted as a relation between the Gaussian curvature of a compact Riemann surface X and its Euler characteristic. It also examines the behavior of the Euler number under finite covering, along with finite subgroups of the group of fractional linear transformations PSL(2, C). Finally, it presents some basic facts about the classical Gauss hypergeometric functions of one complex variable, triangle groups acting discontinuously on one of the simply connected Riemann surfaces, and the hypergeometric monodromy group.
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Ley, Steven V. Synthesis : Carbon with One Heteroatom Attached by a Single Bond, Volume Volume 2 (Comprehensive Organic Functional Group Transformations). Pergamon, 2003.

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Chapitres de livres sur le sujet "One-Parameter group of transformation"

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Ibragimov, N. H., W. F. Ames, R. L. Anderson, V. A. Dorodnitsyn, E. V. Ferapontov, R. K. Gazizov, N. H. Ibragimov et S. R. Svirshchevskii. « One-Parameter Transformation Groups ». Dans CRC Handbook of Lie Group Analysis of Differential Equations, Volume I, 7–28. Boca Raton : CRC Press, 2023. http://dx.doi.org/10.1201/9781003419808-3.

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Flori, Cecilia. « One-Parameter Group of Transformations and Stone’s Theorem ». Dans Lecture Notes in Physics, 373–89. Berlin, Heidelberg : Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-35713-8_20.

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Lie, Sophus. « Complete Systems Which Admit All Transformations of a One-term Group ». Dans Theory of Transformation Groups I, 151–59. Berlin, Heidelberg : Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-46211-9_8.

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Roytvarf, Alexander A. « One-Parameter Groups of Linear Transformations ». Dans Thinking in Problems, 197–290. Boston : Birkhäuser Boston, 2012. http://dx.doi.org/10.1007/978-0-8176-8406-8_10.

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Grafarend, Erik W., Rey-Jer You et Rainer Syffus. « C 10(3) : The Ten Parameter Conformal Group as a Datum Transformation in Three-Dimensional Euclidean Space ». Dans Map Projections, 673–83. Berlin, Heidelberg : Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-642-36494-5_24.

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Shatilo, Liudmyla, et Robert Hofmann. « Depicting Trypillia : Emergence and Transformation of the Realistic Style ». Dans Perspectives on Socio-environmental Transformations in Ancient Europe, 221–56. Cham : Springer Nature Switzerland, 2024. http://dx.doi.org/10.1007/978-3-031-53314-3_8.

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AbstractTransformation processes have not only different scales, significance and aspects. They can also be reflected in social behavior, and thus also in material culture. This chapter examines various categories of objects of non-utilitarian nature with realistically depicted elements. By analysing a Trypillian group of ceramic objects and anthropomorphic figurines from the Middle and Late Neolithic tell Vinča-Belo Brdo, we can show their temporal and spatial change within the transformation of aggregated settlements during the periods with the highest population density. Our analysis of one of the components of material culture shows huge prospects for studying anatomy and different aspects of transformations and their reflections.
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Morimoto, Masaharu. « Most of the standard spheres have one fixed point actions of A5 ». Dans Transformation Groups, 240–58. Berlin, Heidelberg : Springer Berlin Heidelberg, 1989. http://dx.doi.org/10.1007/bfb0085614.

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Lie, Sophus. « One-Term Groups and Ordinary Differential Equations ». Dans Theory of Transformation Groups I, 61–91. Berlin, Heidelberg : Springer Berlin Heidelberg, 2015. http://dx.doi.org/10.1007/978-3-662-46211-9_4.

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« One-Parameter Transformation Groups ». Dans Dynamical Symmetry, 105–34. WORLD SCIENTIFIC, 2010. http://dx.doi.org/10.1142/9789814291378_0004.

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« One-parameter groups and their invariants ». Dans Transformation Groups and Lie Algebras, 23–49. WORLD SCIENTIFIC / HIGHER EDUCATION PRESS, CHINA, 2013. http://dx.doi.org/10.1142/9789814460859_0002.

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Actes de conférences sur le sujet "One-Parameter group of transformation"

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Lee, Tzu Ying. « Group Cohesiveness and Organizational Commitment : Moderated by Transformational Leadership ». Dans Japan International Business and Management Research Conference. RSF Press & RESEARCH SYNERGY FOUNDATION, 2020. http://dx.doi.org/10.31098/jibm.v1i1.211.

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This study investigated to what extent group cohesiveness is related to organizational commitment and transformational leadership. In the advent of generational transformation, it is impossible to achieve organizational goals and create win-win partnerships between supervisors and subordinates merely by resorting to organizational discipline or role behavior. This study, based on a quality interview survey, explored the influence of team cohesiveness on organizational commitment with transformational leadership as a moderating variable. Literature related to the real estate agency industry was firstly reviewed and compiled for overall understanding. In-depth onsite expert interviews were conducted for inducing internal and external affecting factors. Actual cases were analyzed. The influence of team behavior and group cohesiveness on organizational commitment was verified. It was found. Additionally, supervisors' positive transformational leadership and supportive behavior could lead to positive organizational cohesiveness. This is regarded as one of the key success factors of management. Transformational leadership behaviors that can boost positive group cohesiveness should be encouraged. Such behaviors can not only boost group cohesiveness but also enable the team to achieve the team goal efficiently.
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Chiao, Raymond Y., Paul G. Kwiat, William A. Vareka et Thomas F. Jordan. « Lorentz-group Berry phases in squeezed light ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1988. http://dx.doi.org/10.1364/oam.1988.mr17.

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The Berry phases most often observed in experiments are produced by rotations. Berry phases produced by Lorentz transformations are almost as simple mathematically. They have been discussed at length, but there has been no suggestion of observing them in an experiment. Indeed, it has been shown that in one context they can be removed by a canonical transformation; thus they appear to be a property of the mathematical description that could not be observed physically. Here we show that the essential element of these Berry phases could be observed as a change of phase of the electromagnetic field in squeezed states of light or microwaves, as could be produced by degenerate parametric amplifiers. It could be seen as a fringe shift in interference experiments. In this way, a physical effect of the squeezing could be measured without measuring anything like photon statistics or noise.
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Kauderer, Mark. « k-dimensional Fourier transforms in n-dimensional first order systems ». Dans OSA Annual Meeting. Washington, D.C. : Optica Publishing Group, 1992. http://dx.doi.org/10.1364/oam.1992.thg1.

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Ordinarily, having an n-dimensional operator relation implies operator relations for all dimensions less than n as well. However, for Fourier transforms this is not so. Only the effect of one-dimensional Fourier transforms in two-dimensional first order systems has been solved previously.1 A partial Fourier transform applied to a nonsingular linear transformation produces a Ohio' transformation, i.e., a matrix pivot. This implies a new definition of the symplectic group SP(n, C) for n ≥ 4 as the group generated by n-dimensional nonsingular linear transformations and the n one-dimensional Fourier transforms. This also provides an alternative method for generalizing low-dimensional results to higher dimensions. Several apparently new determinantal identities generalizing Chio's theorem are immediate consequences.
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Cotsaftis, Michel, Erno Keskinen, Juha Miettinen, Olli Nuutila et Pekka Salmenpera. « Vibration Analysis of Rotors in Rolling Contact : Laboratory Application and Scaling Group ». Dans ASME 2005 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. ASMEDC, 2005. http://dx.doi.org/10.1115/detc2005-84466.

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It is mainly shown that, from their basic origin, vibration rotor modes are following a fixed pattern which has been theoretically analyzed. Various perturbation effects related to geometrical or physical defects are evaluated. Three main classes of modes are distinguished which correspond to different origins: global “outside” modes, “static” rotating rotor deformation modes, and real dynamic excited deformation modes representing the only power sink strictly related to rolls deformation. Good agreement is found for measurements from an industrial paper mill plant operating unit and for experimental observations from a laboratory experiment with large mode coupling. In both cases, most of observed modes are belonging to the first two classes, which can be cured aside by appropriate respective frame shielding and roll grinding. For the last class, a continuous three parameter transformation group is constructed so that the industrial unit and the university apparatus both belong to it, allowing to study properties of the first one on the more manageable second one. Because the modes are sharply peaked due to metal stiffness and weak damping, there exists broad rotation frequency windows where the total mode amplitude is small enough for the system to be preferentially operated.
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Ong, Zi Yuan, Kah Kien Chye, Huay Wen Kang et Chi Wee Tan. « A Flower Recognition System using Deep Neural Network Coupled with Visual Geometry Group 19 Architecture ». Dans International Conference on Digital Transformation and Applications (ICDXA 2021). Tunku Abdul Rahman University College, 2021. http://dx.doi.org/10.56453/icdxa.2021.1012.

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Computer vision is one of the basic features to streamline processes like robotic process automation and digital asset management. Computer vision has come a long way in terms of its capabilities and what it can provide and do for different industries. Object detection and image detection are just some of the few applications provided by computer vision. However, this field is still relatively young and prone to challenges. The first is the lack of wellannotated images to train the algorithms to perform optimally, and the second being lack of accuracy when applied to real-world images different from the ones from the training dataset. As such, this paper aims to fine-tune pre-trained machine learning models, which are ResNet50 and VGG19 as well as training a new SqueezeNet inspired model from scratch to create a flower recognition model that can process and remember large amounts of flower species data. In conclusion, VGG19 was found to perform the best on both the 5 Categories and Flower-102 dataset, with an accuracy of 88% and 84% respectively. Keywords: VGG19, Transfer Learning, Deep Learning, Flower Recognition, Neural Network
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Turner, Astrid, Irene Lubbe, Liz Wolvaardt et Lizeka Napoles. « Navigating curriculum transformation : charting our course ». Dans Fifth International Conference on Higher Education Advances. Valencia : Universitat Politècnica València, 2019. http://dx.doi.org/10.4995/head19.2019.9129.

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The 2015 student-led #FeesMustFall campaign in South Africa initiated at some universities, and accelerated at others, indepth discussions and reflections about curriculum transformation within the perceived ivory towers of learning. Three years later, the mandate to implement transformation is clear from all levels but what is uncertain is the operationalization of the official transformation framework at the University of Pretoria. The aim of the project presented is to chart the process followed by one of the four Schools of the Faculty of Health Sciences to deconstruct this transformation framework. As part of a three phased programme, a workshop of diverse staff using a modified nominal technique was held in 2018. It resulted in a visual tool of 19 specific statements considered evidence of personal practice that supports and advances the drive for transformation. This tool will be used to share practices and instil individual and School accountability for everone’s role in curriculum transformation. In conclusion, complex policy ideals and technical terminology can be translated into practical, appropriate actions by a diverse group of staff and students. The use of a modified nominal group technique was an efficient way to do this by generating an easy to use visual tool.
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Torok, J. S. « A Constructive Method for Locating Periodic Solutions of Linear and Nonlinear Systems ». Dans ASME 1993 Design Technical Conferences. American Society of Mechanical Engineers, 1993. http://dx.doi.org/10.1115/detc1993-0087.

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Abstract In this paper, an efficient algorithm is developed for the identification of stable steady-state solutions to periodically-forced linear and nonlinear dynamical systems. The developed method is based on mapping techniques introduced by Henri Poincare and the theory of one-parameter transformation groups. The algorithm successfully identifies initial conditions which give rise to strictly periodic orbits.
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Инджов, Иво. « MEDIA CONSUMPTION AND ELECTION CAMPAIGNSIN BULGARIA ». Dans Dynamics of the Digital Transformation in the Media Environment. Faculty of Journalism and Mass Communication, 2024. http://dx.doi.org/10.60060/gggj8203.

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The sixth in the last three years of parliamentary elections in Bulgaria is an occasion to explore the role of the media as a key actor in election campaigns. The work is based on data analysis (primary and secondary) for media consumption from quantitative studies and so -called cabinet study. It was established that Bulgaria, despite some specifics, fits into the global trends of media consumption. First, television still remains the leading media for satisfying the information needs of the population. Second, however, social networks and online media are on the rise. Third - in Bulgaria, researches usually put all online media under one “hat”, but the strong presence of traditional media on the Internet should also be taken into account. Fourth, radio and the press are now secondary media, but they still matter to older people. During election campaigns, the picture is generally a small copy of the usual consumption. Television still holds the palm of the championship, but it is already shaken by the new media. Three groups of media users can be distinguished, which are more important for political communication. People up to 30 years old, who by praville are electoral passive, are “immunized” against the television product. At the same time, it can be predicted that for understandable reasons, after 10-20 years, the 60+ group will begin to use many more new media. People aged 40+, however, are ideal target groups for election campaigns with content overflow and television messages in the new media and vice versa
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Инджов, Иво. « MEDIA CONSUMPTION AND ELECTION CAMPAIGNS IN BULGARIA ». Dans Dynamics of the Digital Transformation in the Media Environment. Faculty of Journalism and Mass Communication, 2024. http://dx.doi.org/10.60060/ii.2024.23.57-75.

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The sixth in the last three years of parliamentary elections in Bulgaria is an occasion to explore the role of the media as a key actor in election campaigns. The work is based on data analysis (primary and secondary) for media consumption from quantitative studies and so -called cabinet study. It was established that Bulgaria, despite some specifics, fits into the global trends of media consumption. First, television still remains the leading media for satisfying the information needs of the population. Second, however, social networks and online media are on the rise. Third - in Bulgaria, researches usually put all online media under one “hat”, but the strong presence of traditional media on the Internet should also be taken into account. Fourth, radio and the press are now secondary media, but they still matter to older people. During election campaigns, the picture is generally a small copy of the usual consumption. Television still holds the palm of the championship, but it is already shaken by the new media. Three groups of media users can be distinguished, which are more important for political communication. People up to 30 years old, who by praville are electoral passive, are “immunized” against the television product. At the same time, it can be predicted that for understandable reasons, after 10-20 years, the 60+ group will begin to use many more new media. People aged 40+, however, are ideal target groups for election campaigns with content overflow and television messages in the new media and vice versa.
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Datta, S., A. Chattopadhyaya, S. Chattopadhyay et A. Das. « Harmonic Distortion, Inter-harmonic Group Magnitude and Discrete Wavelet Transformation based Statistical Parameter Estimation for Line to Ground Fault Analysis in Microgrid System ». Dans Michael Faraday IET International Summit 2020 (MFIIS 2020). Institution of Engineering and Technology, 2021. http://dx.doi.org/10.1049/icp.2021.1087.

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Rapports d'organisations sur le sujet "One-Parameter group of transformation"

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Dachs, Bernhard, et Matthias Weber. National recovery packages, innovation, and transformation. Project for the Austrian Council for Research and Technology Development. Rat für Forschung und Technologieentwicklung, janvier 2022. http://dx.doi.org/10.22163/fteval.2022.604.

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The COVID-19 pandemic hit Europe hard, and measures to contain the spread of the COVID-19 have resulted in a deep recession in 2020. To fight this recession, national governments have mobilised considerable funds to support the economy and prepare for a rebound in the following years. In addition to national efforts, the European Commission has initiated NextGenerationEU, a 750 bn EUR package to support Europe’s recovery, and the Recovery and Resilience Facility (RRF) as its biggest component. The aim of this package is to make Europe’s economies more resilient to future challenges while supporting them in the green and digital transitions. Immediate support for the economy is important to stabilize employment and prevent vicious cycles that appeared during the Great Depression of the 1930s. However, these measures may also hamper change for good when they only aim at restoring the status quo before the crisis. Times of crisis are always times of transformation and innovation – this may also be true for the COVID-19 crisis of 2020 and 2021.The crisis may provide a good environment to push for transformative innovation. The rapid development of vaccines against COVID-19 is a strong sign for the adaptability of national innovation systems to new challenges, and the sense of urgency for change is high. However, one may also ask if national funding and the EU recovery packages are agile enough to support new ideas, new firms and new business models, as potential triggers of transformation. Against this background, the project will analyse Austria’s response to the economic effects of the crisis from an innovation and transformation perspective. In particular, the project will look at the recovery packages from the perspective of the ‘protect-prepare-transform’ framework proposed by the EU Expert group on the Societal and Economic Impact of Research and Innovation (ESIR, 2020): the need to protect the overall wellbeing of individuals during the crisis, the need to prepare for future pandemics and crises and the need to transform the European economy and society towards more resilience against future crises. The analysis will include national funds as well as Austria’s Recovery and Resilience Plan (RRP), i.e. its proposal to the Recovery and Resilience Facility (RRF) of the European Commission. This multi-level nature of the recovery measures is further complicated by regional initiatives to mobilise further resources such as EU Structural Funds to fight the COVID-19 crisis.
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Haider, Huma. Scalability of Transitional Justice and Reconciliation Interventions : Moving Toward Wider Socio-political Change. Institute of Development Studies (IDS), mars 2021. http://dx.doi.org/10.19088/k4d.2021.080.

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Literature focusing on the aftermath of conflict in the Western Balkans, notes that many people remain focused on stereotypes and prejudices between different ethnic groups stoking fear of a return to conflict. This rapid review examines evidence focussing on various interventions that seek to promote inter-group relations that are greatly elusive in the political realm in the Western Balkan. Socio-political change requires a growing critical mass that sees the merit in progressive and conciliatory ethnic politics and is capable of side-lining divisive ethno-nationalist forces. This review provides an evidence synthesis of pathways through which micro-level, civil-society-based interventions can produce ‘ripple effects’ in society and scale up to affect larger geographic areas and macro-level socio-political outcomes. These interventions help in the provision of alternative platforms for dealing with divisive nationalism in post-conflict societies. There is need to ensure that the different players participating in reconciliation activities are able to scale up and attain broader reach to ensure efficacy and hence enabling them to become ‘multiplier of peace.’ One such way is by providing tools for activism. The involvement of key people and institutions, who are respected and play an important role in the everyday life of communities and participants is an important factor in the design and success of reconciliation initiatives. These include the youth, objective media, and journalists. The transformation of conflict identities through reconciliation-related activities is theorised as leading to the creation of peace constituencies that support non-violent approaches to conflict resolution and sustainable peace The success of reconciliation interventions largely depends on whether it contributes to redefining otherwise antagonistic identities and hostile relationships within a community or society.
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Lustosa Rosario, Ana Carolina, Bar Ben Yaacov, Cecilia Franco Segura, Elena Arias Ortiz, Elena Heredero, Juanita Botero, Patrick Brothers, Thiago Payva et Maria Spies. Education Technology in Latin America and the Caribbean. Inter-American Development Bank, décembre 2021. http://dx.doi.org/10.18235/0003828.

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Education Technology has the potential to be a powerful engine for transformation in Latin America and the Caribbean, however the size of the challenge is formidable. The region faces the worst socio-economic crisis in more than a century, is one of the lowest performing education systems globally and has a chronic skills gap. New solutions, new approaches and new thinking is needed now more than ever. Stakeholders in the region see the potential for EdTech to support greater access to education, better experiences and outcomes for learners, and greater efficiency. Interest and investment in EdTech is increasing, with over 1500 EdTech startups across LAC and a six-fold increase in private capital investment in the last year alone. This report combines the strengths of the IDB group and HolonIQ, two organizations passionate about the future of Latin America and the Caribbean with a belief in the power of education to change futures. It is in the spirit of collaboration that this project set out to map EdTech in the LAC region, surface the innovations and impact that EdTech is making, as well as to identify the challenges faced and opportunities for greater impact. The key recommendations in this report are designed to provide policy-makers, education leaders, EdTech entrepreneurs, investors and other stakeholders with information and inspiration to support their initiatives that improve and accelerate education technology for the region, in order to have a materially positive impact on education outcomes in the region.
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Rodriguez, Russell, et Stanley Freeman. Characterization of fungal symbiotic lifestyle expression in Colletotrichum and generating non-pathogenic mutants that confer disease resistance, drought tolerance, and growth enhancement to plant hosts. United States Department of Agriculture, février 2005. http://dx.doi.org/10.32747/2005.7587215.bard.

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Fungal plant pathogens are responsible for extensive annual crop and revenue losses throughout the world. To better understand why fungi cause diseases, we performed gene-disruption mutagenesis on several pathogenic Colletotrichum species and demonstrated that pathogenic isolates can be converted to symbionts (mutualism, commensalism, parasitism) expressing non-pathogenic lifestyles. The objectives of this proposal were to: 1- generate crop-specific mutants by gene disruption that express mutualistic lifestyles, 2- assess the ability of the mutualists to confer disease resistance, drought tolerance, and growth enhancement to host plants, 3- compare fslm1 sequences and their genomic locations in the different species, and 4- document the colonization process of each Colletotrichum species.It was demonstrated that wildtype pathogenic Colletotrichum isolates, can be converted by mutation from expressing a pathogenic lifestyle to symbionts expressing non-pathogenic lifestyles. In the US, mutants of Colletotrichum were isolated by homologous gene disruption using a vector containing a disrupted FSlm1 sequence while in Israel, C. acutatum mutants were selected by restriction enzyme mediated integration (REMI) transformation. One group (US) of non-pathogenic mutants conferred disease protection against pathogenic species of Colletotrichum, Fusarium, and Phytophthora; drought tolerance; and growth enhancement to host plants. These mutants were defined as mutualists and disease resistance correlated to a decrease in the time required for hosts to activate defense systems when exposed to virulent fungi. The second group (Israel) of non-pathogenic mutants did not confer disease resistance and were classified as commensals. In addition, we demonstrated that wildtype pathogenic Colletotrichum species can express non-pathogenic lifestyles, including mutualism, on plants they colonize asymptomatically. The expected long term contribution of this research to agriculture in the US and Israel is threefold. Host-specific mutualists will be utilized in the various crops to confer (1) disease resistance to reduce dependence on chemical fungicides; (2) drought tolerance to reduce water consumption for irrigation; (3) growth enhancement to increase yields.
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Rohwerder, Brigitte. Inclusion of Marginalised Groups in Social Assistance in Crises. Institute of Development Studies (IDS), février 2022. http://dx.doi.org/10.19088/basic.2022.023.

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Leave no one behind is the central, transformative promise of the Sustainable Development Goals (SDGs), aimed at reaching the poorest and combating discrimination and (multiple and intersecting) inequalities that undermine people’s human rights. The importance of leaving no one behind is vital in contexts of recurrent shocks, climate and humanitarian crises, protracted conflict, and forced displacement that cause disruption, deprivation, and a lack of access to basic needs. Crises often exacerbate existing inequalities and vulnerabilities for socially excluded and marginalised people, including women and girls, children and youth, older people, people with disabilities, ethnic and religious minorities, and sexual and gender minorities. Social assistance, in the form of government provided or humanitarian assistance, seeks to alleviate crisis impacts. The structures, systems, and barriers that exclude some people generally can also exclude them from social assistance in crises. Such exclusion, both before and during a crisis, can increase deprivation, reduce resilience to shocks, and exacerbate protection risks by increasing people’s vulnerability to exploitation and abuse. Crises, consequently, can disproportionately impact marginalised people. A lack of inclusive social assistance programming thus undermines rights, ethics, and effectiveness in crises – as explored in this summary briefing of the three BASIC Research working papers on inclusion.
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Crouch, Luis, et Deborah Spindelman. Purpose-Driven Education System Transformations : History Lessons from Korea and Japan. Research on Improving Systems of Education (RISE), mars 2023. http://dx.doi.org/10.35489/bsg-rise-wp_2023/139.

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This paper is an essay in comparative educational history and its possible relevance to educational development today. It addresses the question of whether Japan and Korea’s history in using educational development to further national development can be useful as (partial) models for dealing with the educational challenges of today’s lower- and lower-middle income countries. The hypothesis of the paper is that there is much to learn from these countries, but that the lessons one could learn are not at all obvious or superficial, and are only partially about what was done (specific education policies) and are more importantly about how it was done (the high purpose and thoroughness of policy engagement). The paper first characterizes educational development, especially in terms of the intense emphasis on equality of high achievement in Korea and Japan, in quantitative terms, to demonstrate that these countries possess certain admirable characteristics. Caveats regarding learner stress and rote learning are dealt with by looking at the relevant statistics. A framework for assessing the quality of policy borrowing processes is built, based on the literature on this subject. The paper then analyzes the historical development of education as a means of resisting Western colonialist probes into Japan and Korea (end of the 19th C), but also Japan itself into Korea (first half of 20th C). How both countries borrowed from the West, but in a contested and very deep manner, and as part of a resistance to being colonized, is documented. The paper also shows that part of the healthy, contested borrowing was the involvement of teacher groups and civil society. The paper concludes by taking into consideration the fraught issue that potentiating the role of education in national development could be seen as tantamount to using education for nationalism. The paper links to the possibility that there may be a more inclusive and rights-oriented use of the concept of the nation to foster human well-being, and that education could play a role in such processes. Some practical suggestions for taking these ideas forward, or at least exploring them in more depth, are made at the very end.
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Lundgren, Anna, Alex Cuadrado, Mari Wøien Meijer, Hjördís Rut Sigurjónsdottir, Eeva Turunen, Viktor Salenius, Jukka Teräs, Jens Bjørn Gefke Grelck et Stian Lundvall Berg. Skills Policies - Building Capacities for Innovative and Resilient Nordic Regions. Nordregio, novembre 2020. http://dx.doi.org/10.6027/r2020:17.1403-2503.

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Long-term trends in Nordic societies (such as ageing populations), along with rapid social transformations (like those brought about by automation and digitalisation), have resulted in increased attention being paid to skills and skills enhancement – not least from policymakers looking to cope with those challenges. However, skills are complex and many actors are involved in their promotion and provision. In this study, we focus on the regional level, which is the point of scale at which the demand for, and supply of, various skills is often articulated. In order to respond to the research question concerning How regions work with skills, six case studies were conducted in 2019 and 2020. That meant one case study in each of the Nordic countries. Those selected were Pohjois-Karjala (North Karelia, Finland), Värmland (Sweden), Hovedstaden (Denmark), Hedmark and Oppland (Norway), Norðurland eystra (Northeastern Region, Iceland), and one in Greenland. This report on skills for resilient and innovative regions is part of a series of reports conducted on behalf of the Nordic Thematic Group for Innovative and Resilient Regions 2017–2020, within the Nordics Cooperation Program for Regional Development and Planning, and under the aegis of the Nordics Council of Ministers.
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Canto, Patricia, dir. The New Complexity of Local Production and the Enlightened Role of Industrial Policy. Universidad de Deusto, 2013. http://dx.doi.org/10.18543/xfkm3607.

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Within this specific contribution we focus on a group of structural transformations that take place within local production systems, namely clusters and districts. This change represents one of the responses of the western economies to the challenges put forth by the emerging powers (e.g. China and the likes). The central idea of this work revolves around the concept of ‘cluster’, which created a heated debate over the past two decades. In fact, some stressed the relevance of the width of the ‘interconnected activities and institutions’ that compose a specific cluster, whereas others tended to equate the concept of cluster with that of district in key aspects such as geographical reach and width of activities. Within this debate, this work offers two meaningful elements. First of all, we focus on new cluster formations that represent the new industrial complexity of local production systems across the western world (mainly Europe) that respond to new challenges set by globalization. In this way, we may thus verify whether former conceptualizations are definitive or may incorporate new features. Secondly and simultaneously, the relevance of a proactive regional policy approach is discussed as a means to build up such competitive response to globalization.
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Droby, Samir, Joseph W. Eckert, Shulamit Manulis et Rajesh K. Mehra. Ecology, Population Dynamics and Genetic Diversity of Epiphytic Yeast Antagonists of Postharvest Diseases of Fruits. United States Department of Agriculture, octobre 1994. http://dx.doi.org/10.32747/1994.7568777.bard.

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One of the emerging technologies is the use of microbial agents for the control of postharvest diseases of fruits and vegetables. A number of antagonistic microorganisms have been discovered which have the potential to effectively control postharvest diseases. Some of this technology has been patented and commercial products such as AspireTM (Ecogen Corporatin, Langhorne, PA, USA), Biosave 10TM and Biosave 11TM (Ecoscience Inc., Worchester, MA, USA) have been registered for commercial use. The principal investigator of this project was involved in developing the yeast-based biofungicide-AspireTM and testing its efficacy under commercial conditions. This research project was initiated to fill the gap between the knowledge available on development and commercial implementation of yeast biocontrol agents and basic understanding of various aspects related to introducing yeast antagonists to fruit surfaces, along with verification of population genetics. The main objectives of this study were: Study ecology, population dynamics and genetic diversity of the yeast antagonists Candida guilliermondii, C. oleophila, and Debaryomyces hansenii, and study the effect of preharvest application of the yeast antagonist C. oleophila naturally occurring epiphytic microbial population and on the development of postharvest diseases of citrus fruit during storage. Our findings, which were detailed in several publications, have shown that an epiphytic yeast population of grapefruit able to grow under high osmotic conditions and a wide range of temperatures was isolated and characterized for its biocontrol activity against green mold decay caused by Penicillium digitatum. Techniques based on random amplified polymorphic DNA (RAPD) and arbitrary primed polymerase chain reaction (ap-PCR), as well as homologies between sequences of the rDNA internal transcribed spacers (ITS) and 5.8S gene, were used to characterize the composition of the yeast population and to determine the genetic relationship among predominant yeast species. Epiphytic yeasts exhibiting the highest biocontrol activity against P. digitatum on grapefruit were identified as Candida guilliermondii, C. oleophila, C. sake, and Debaryomyces hansenii, while C. guilliermondii was the most predominant species. RAPD and ap-PCR analysis of the osmotolerant yeast population showed two different, major groups. The sequences of the ITS regions and the 5.8S gene of the yeast isolates, previously identified as belonging to different species, were found to be identical. Following the need to develop a genetically marked strain of the yeast C. oleophila, to be used in population dynamics studies, a transformation system for the yeast was developed. Histidine auxotrophy of C. oloephila produced using ethyl methanesulfonate were transformed with plasmids containing HIS3, HIS4 and HIS5 genes from Saccharomyces cerevisiae. In one mutant histidin auxotrophy was complemented by the HIS5 gene of S. cerevisiae is functionally homologous to the HIS5 gene in V. oleophila. Southern blot analysis showed that the plasmid containing the S. cerevisiae HIS5 gene was integrated at a different location every C. oleophila HIS+ transformant. There were no detectable physiological differences between C. oleophila strain I-182 and the transformants. The biological control ability of C. oleophila was not affected by the transformation. A genetically marked (with b-glucuronidase gene) transformant of C. oleophila colonized wounds on orange fruits and its population increased under field conditions. Effect of preharvest application of the yeast C. oleophila on population dynamics of epiphytic microbial population on wounded and unwounded grapefruit surface in the orchard and after harvest was also studied. In addition, the effect of preharvest application of the yeast C. oleophila on the development of postharvest decay was evaluated. Population studies conducted in the orchard showed that in control, non-treated fruit, colonization of wounded and unwounded grapefruit surface by naturally occurring filamentous fungi did not vary throughout the incubation period on the tree. On the other hand, colonization of intact and wounded fruit surface by naturally occurring yeasts was different. Yeasts colonized wounded surface rapidly and increased in numbers to about two orders of magnitude as compared to unwounded surface. On fruit treated with the yeast and kept on the tree, a different picture of fungal and yeast population had emerged. The detected fungal population on the yeast-treated intact surface was dramatically reduced and in treated wounds no fungi was detected. Yeast population on intact surface was relatively high immediately after the application of AspireTM and decreased to than 70% of that detected initially. In wounds, yeast population increased from 2.5 x 104 to about 4x106 after 72 hours of incubation at 20oC. Results of tests conducted to evaluate the effect of preharvest application of AspireTM on the development of postharvest decay indicated the validity of the approach.
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Delmer, Deborah P., Douglas Johnson et Alex Levine. The Role of Small Signal Transducing Gtpases in the Regulation of Cell Wall Deposition Patterns in Plants. United States Department of Agriculture, août 1995. http://dx.doi.org/10.32747/1995.7570571.bard.

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The combined research of the groups of Delmer, Levine and Johnson has led to a number of interesting findings with respect to the function of the small GTPase Rac in plants and also opened up new leads for future research. The results have shown: 1) The Rac13 protein undergoes geranylgeranlyation and is also translocated to the plasma membrane as found for Rac in mammals; 2) When cotton Rac13 is highly- expressed in yeast, it leads to an aberrant phenotype reminiscent of mutants impaired in actin function, supporting a role for Rac13 in cytoskeletal organization; 3) From our searches, there is no strong evidence that plants contain homologs of the related CDC42 genes found in yeast and mammals; 4) We have identified a rather unique Rac gene in Arabidopsis that has unusual extensions at both the N- and C-terminal portions of the protein; 5) New evidence was obtained that an oxidative burst characterized by substantial and sustained production of H202 occurs coincident with the onset of secondary wall synthesis in cotton fibers. Further work indicates that the H202 produced may be a signal for the onset of this phase of development and also strongly suggests that Rac plays an important role in signaling for event. Since the secondary walls of plants that contain high levels of lignin and cellulose are the major source of biomass on earth, understanding what signals control this process may well in the future have important implications for manipulating the timing and extent of secondary wall deposition. 6) When the cotton Rac13 promoter is fused to the reporter gene GUS, expression patterns in Arabidopsis indicate very strong and specific expression in developing trichomes and in developing xyelm. Since both of these cell types are engaged in secondary wall synthesis, this further supports a role for Rac in signaling for onset of this process. Since cotton fibers are anatomically defined as trichomes, these data may also be quite useful for future studies in which the trichomes of Arabidopsis may serve as a model for cotton fiber development; the Rac promoter can therefore be useful to drive expression of other genes proposed to affect fiber development and study the effects on the process; 7) The Rac promoter has also been shown to be the best so far tested for use in development of a system for transient transformation of developing cotton fibers, a technique that should have many applications in the field of cotton biotechnology; 8) One candidate protein that may interact with Rac13 to be characterized further in the future is a protein kinase that may be analogous to the PAK kinase that is known to interact with Rac in mammals.
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