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Underlying Dynamics (underlying + dynamics)
Selected AbstractsPredictability of river flow and suspended sediment transport in the Mississippi River basin: a non-linear deterministic approachEARTH SURFACE PROCESSES AND LANDFORMS, Issue 6 2005Bellie Sivakumar Abstract As the Mississippi River plays a major role in fulfilling various water demands in North America, accurate prediction of river flow and sediment transport in the basin is crucial for undertaking both short-term emergency measures and long-term management efforts. To this effect, the present study investigates the predictability of river flow and suspended sediment transport in the basin. As most of the existing approaches that link water discharge, suspended sediment concentration and suspended sediment load possess certain limitations (absence of consensus on linkages), this study employs an approach that presents predictions of a variable based on history of the variable alone. The approach, based on non-linear determinism, involves: (1) reconstruction of single-dimensional series in multi-dimensional phase-space for representing the underlying dynamics; and (2) use of the local approximation technique for prediction. For implementation, river flow and suspended sediment transport variables observed at the St. Louis (Missouri) station are studied. Specifically, daily water discharge, suspended sediment concentration and suspended sediment load data are analysed for their predictability and range, by making predictions from one day to ten days ahead. The results lead to the following conclusions: (1) extremely good one-day ahead predictions are possible for all the series; (2) prediction accuracy decreases with increasing lead time for all the series, but the decrease is much more significant for suspended sediment concentration and suspended sediment load; and (3) the number of mechanisms dominantly governing the dynamics is three for each of the series. Copyright © 2005 John Wiley & Sons, Ltd. [source] Jungle Law in the Orchard: Comparing Globalization in the New Zealand and Chilean Apple IndustriesECONOMIC GEOGRAPHY, Issue 4 2002Megan K. L. McKenna Abstract: Restructuring in the global apple market is leading to a pronounced tightening in the competitive spaces occupied by Southern Hemisphere producers. For New Zealand and Chile, the world's two most successful apple-exporting countries, significant challenges are presented by projected industry trends, such as declining profitability in the global industry, increased world production, and the continued static demand in key markets. In particular, falling prices in Europe and North America for many key varieties and concomitant lower returns to growers are threatening serious and pervasive impacts. This article explores some of these challenges in the context of the significantly different positions occupied by New Zealand and Chile within the global fresh fruit and vegetable complex. An analysis of the two countries' industries, particularly comparing issues of regulation and innovative varietal development, shows that global food complexes have highly variable spatial expressions, given their process-based nature and underlying dynamics of contestation. Focusing on the increased competition between the New Zealand and Chilean apple industries, the discussion sheds light on wider emerging competitive dynamics within the global fruit industry. The example of the recent Pacific Rose crisis, which involved Chilean "theft" of an exclusive New Zealand apple variety, is used to illustrate the emergence of "jungle law" in the Southern Hemisphere apple industries. [source] Reactance and the dynamics of disagreement: multiple paths from threatened freedom to resistance to persuasionEUROPEAN JOURNAL OF SOCIAL PSYCHOLOGY, Issue 5 2006Paul J. Silvia Many experiments show that threats to attitudinal freedom create reactance, but the underlying dynamics of reactance-based disagreement have not received much attention. The present experiments identified two paths from threats to disagreement. In one path, threats to attitudinal freedom directly motivate disagreement; in the other, negative cognitive responses mediate the threat's effect on disagreement. Two experiments demonstrated the causes and consequences of each path from threat to persuasion. When a communicator threatened freedom at the beginning of the message, unfavorable cognitive responses (counterarguing, negative perceptions of the source's credibility) fully mediated the effect of threat on disagreement. When the threat appeared at the end of the message however, threat had a direct, unmediated effect on disagreement (Experiment 1). The two paths had different consequences for sleeper effects: disagreement rooted in negative cognitive responses persisted, whereas disagreement directly motivated by the threat declined when the threat was removed (Experiment 2). Implications for reactance and for threat-based sleeper effects are discussed. Copyright © 2006 John Wiley & Sons, Ltd. [source] GLOBALIZATION AND EXTERRITORIALITY IN METROPOLITAN CAIROGEOGRAPHICAL REVIEW, Issue 3 2005PETRA KUPPINGER ABSTRACT. Rapid construction of new spaces like hotels, malls, private clubs, and gated communities in Greater Cairo, Egypt produces structures disconnected spatially and conceptually from most of the existing urban fabric. Their spatial concepts and practices, as well as architectural forms and expertise, are based largely on globally available models. Planning and construction are guided by the search for security in the face of real or imagined fear of the urban masses and political upheaval. Concrete walls, guarded entrances, and high-tech security technology bear witness to these fears. Analysis of the Mena House Hotel, the Grand Egyptian Museum project, and the First Mall in Giza shows how these projects globalize Cairo and localize the global. Often these globalized spaces are remade by creating local and regional ties and design features that were not anticipated by the planners. Such changes shed light on underlying dynamics and contribute to a better understanding of in situ globalization. Whereas their physical features tend to accentuate their globalized nature, these spaces do not exist in isolation from their geographical and cultural contexts. Their everyday realities tell tales of reterritorialization that are frequently overlooked in scholarly debates. [source] Symbolic methods for invariant manifolds in chemical kineticsINTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 1 2006Simon J. Fraser Abstract Chemical reactions show a separation of time scales in transient decay due to the stiffness of the ordinary differential equations (ODEs) that describe their evolution. This evolution can be represented as motion in the phase space spanned by the concentration variables of the chemical reaction. Transient decay corresponds to a collapse of the "compressible fluid" representing the continuum of possible dynamical states of the system. Collapse occurs sequentially through a hierarchy of nested, attracting, slow invariant manifolds (SIMs), i.e., sets that map into themselves under the action of the phase flow, eventually reaching the asymptotic attractor of the system. Using a symbolic manipulative language, explicit formulas for the SIMs can be found by iterating functional equations obtained from the system's ODEs. Iteration converges geometrically fast to a SIM at large concentrations and, if necessary, can be stabilized at small concentrations. Three different chemical models are examined in order to show how finding the SIM for a model depends on its underlying dynamics. For every model the iterative method provides a global SIM formula; however, formal series expansions for the SIM diverge in some models. Repelling SIMs can be also found by iterative methods because of the invariance of trajectory geometry under time reversal. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [source] Controlled Lagrangians and the stabilization of Euler,Poincaré mechanical systemsINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 3 2001Anthony M. Bloch Abstract In this paper we develop a constructive approach to the determination of stabilizing control laws for a class of Lagrangian mechanical systems with symmetry , systems whose underlying dynamics are governed by the Euler,Poincaré equations. This work extends our previous work on the stabilization of mechanical control systems using the method of controlled Lagrangians. The guiding principle behind our methodology is to develop a class of stabilizing feedback control laws which yield closed-loop dynamics that remain in Lagrangian form. Using the methodology for Euler,Poincaré systems, we analyse stabilization of a satellite and an underwater vehicle controlled with momentum wheels. Copyright © 2001 John Wiley & Sons, Ltd. [source] "I Know I'm a Freierit, But,": How a Key Cultural Frame (En)genders a Discourse of InequalityJOURNAL OF COMMUNICATION, Issue 1 2005Linda-Renée Bloch This article investigates how a key frame of interaction establishes and reinforces gendered social relations within a given culture. It analyzes how the concept of the freier (roughly glossed as "sucker") is used in Israel, interpersonally and via the mass media, to demonstrate how gender is constructed through communication and inextricably bound to the specific cultural context in which it is located. This work exposes how the frame reinforces the underlying dynamics of gender inequality in society, examines the oppositional ways in which it is employed by women, and argues that its use in any form further entrenches the social bias. The article calls for analyses of discourse focusing on nondominant groups, within their specific cultural context, in order to examine the practical distribution of power in society. [source] The allocation of prestigious positions in organizational science: accumulative advantage, sponsored mobility, and contest mobilityJOURNAL OF ORGANIZATIONAL BEHAVIOR, Issue 5 2005C. Chet Miller More than 200 freshly minted doctoral graduates enter the field of organization science every year. A non-trivial number of existing faculty members move from one university to another every year, while other organization science faculty leave academia to enter retirement, consulting, or industry. Despite the importance of this large, complex system of entries and exits, few attempts have been made to explicitly understand how the system works. Drawing upon sociology of science and careers research, we studied the underlying form of the position allocation system by focusing on the relative importance of research success and prior affiliations as antecedents of movement and stability across positions. We used three theoretical models: accumulative advantage, sponsored mobility, and contest mobility. Tracking hundreds of faculty members for 16 years post doctorate, we find a downward cascading of affiliation prestige over time that affects people more dramatically and quickly than we expected, especially women. Accumulative advantage, the most predictive of our models, does help to maintain relative but not absolute prestige, at least until its effects wane in later years of the career. These findings are relevant to scholars interested in the sociology of science, organization scholars interested in the underlying dynamics of their discipline, and individuals making career choices. Copyright © 2005 John Wiley & Sons, Ltd. [source] The Lost Leader: Sir Stafford Northcote and the Leadership of the Conservative Party, 1876,85*PARLIAMENTARY HISTORY, Issue 3 2008NIGEL THOMAS KEOHANE Sir Stafford Northcote has gone down in history as a man who fell short of the ultimate achievement of being prime minister largely because of personal weakness, and lack of political virility and drive. The picture painted by Northcote's political enemies , most notably the Fourth Party , has been accepted uncritically. Yet, political motives lay behind the actions of these supporters, and their harsh black and white portrait is not illustrative of the complexity of the situation in which Northcote found himself. Although individual characteristics undoubtedly played a part in his final political failure, underlying dynamics and structural transformations in politics and political life were more significant. It was more than simply the misfortune in succeeding the exceptionally charismatic Disraeli as leader. Northcote was faced with unparalleled disruption in parliament from Irish Nationalist MPs; the starkly polarised debate on the eastern question left him detached as a moderate. His temperament was better suited to constructive government rather than to opposition. However, following general election defeat in 1880, Northcote was denied this opportunity. Equally, his position in the lower House denied him the capacity to define a clear political critique of the Liberal government. Northcote's leadership of the party reflected the changing nature of British politics as radicals, tories, Irish Nationalists and Unionists increasingly contested the consensual style more appropriate to the political world of Palmerston and the 14th earl of Derby. [source] The Presidency, the Bureaucracy, and Reinvention: A Gentle Plea for Chaos1PRESIDENTIAL STUDIES QUARTERLY, Issue 1 2000DAVID LOWERY The relative influences of the unique and traditional elements of the Clinton-Gore National Performance Review (NPR) episode of bureaucratic reform are examined here as a means of exploring the underlying dynamics of executive-bureaucratic relationships. The first section of the article outlines the reinvention theory underlying NPR. This is followed by an analysis of how NPR deviated from that theory. The third section of the article considers what reforms might have been proposed by NPR had it taken reinvention theory more seriously. And fourth, the author discusses the deeper problems of presidential implementation of any reform not founded on enhanced hierarchical control of the bureaucracy by the White House. Finally, a unidirectional cycle of presidential reform is described, a cycle that seems impervious to and unconnected with scholarly work on management. [source] Grievance: The underlying oedipal configurationTHE INTERNATIONAL JOURNAL OF PSYCHOANALYSIS, Issue 4 2008Michael Feldman In this paper the author describes some of the clinical features encountered in patients who seem to ,nurture' a persistent grievance. He gives clinical examples, and discusses the nature of the powerful underlying dynamics. He suggests that contained within the patient's grievance is a set of phantasies that constitute the expression of his fear and hatred of reality, particularly the reality of the oedipal situation, the child's relationship to the creative parental couple, which Money-Kyrle (1968, 1971) has characterised as an essential element of ,the facts of life'. The phantasies the patient has evolved serve to protect him from envy and jealousy, anxiety and guilt. The primitive oedipal phantasies on which the grievance rests also contribute to the excitement and gratification that are characteristic of the grievance. The analysis of the underlying state of mind helps to account for the persistent grip the grievance has on the patient, and the way this interferes with development. [source] Construction of 2D isomorphism for 2D H, -control of Sturm-Liouville systemsASIAN JOURNAL OF CONTROL, Issue 2 2010Boe-Shong Hong Abstract This work makes possible that H, -loopshaping has a 2D version for the Sturm-Liouville class of distributed parameter systems. Here, the Laplace integral is composite of a Galerkin projection to transform the underlying dynamics, both spatially distributed and temporally varying, into pure algebra, so that any technique of classical control becomes applicable to spatio-temporal analyses and syntheses. Accompanied by this Laplace-Galerkin transform and its inverse are Fourier-Galerkin transforms that constitute a pair of geometrical isomorphism between space-time domain and mode-frequency domain. Based on the isomorphism, Small Gain Theorem and H, -loopshaping can expand on 2D version in terms of mode-frequency responses. Copyright © 2010 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society [source] Femtosecond Time-Resolved Geometry Relaxation and Ultrafast Intramolecular Energy Redistribution in Ag2AuCHEMPHYSCHEM, Issue 2 2005Thorsten M. Bernhardt Dr. Abstract The ultrafast dynamics of the bimetallic cluster Ag2Au is investigated by pump,probe negative ion-to-neutral-to-positive ion (NeNePo) spectroscopy. Preparation of the neutral cluster in a highly nonequilibrium state by electron detachment from the mass-selected anion, and subsequent probing of the neutral nuclear dynamics through two-photon ionization to the cationic state, leads to strongly probe-energy-dependent transient cation-abundance signals. The origin of this pronounced time and wavelength dependence of the ionization probability on the femtosecond scale is revealed by ab initio theoretical simulations of the transient spectra. Based on the analysis of underlying dynamics, two fundamental processes involving geometry relaxation from linear to triangular structure followed by ultrafast intramolecular vibrational energy redistribution (IVR) have been identified and for the first time experimentally observed in the frame of NeNePo spectroscopy under conditions close to zero electron kinetic energy. [source] | |||||||||||||||||||