A non-autonomous strongly damped wave equation: Existence and continuity of the pullback attractor

In this paper we consider the strongly damped wave equation with time-dependent terms u(tt) - Delta u - gamma(t)Delta u(t) + beta(epsilon)(t)u(t) = f(u), in a bounded domain Omega subset of R(n), under some restrictions on beta(epsilon)(t), gamma(t) and growth restrictions on the nonlinear term f. The function beta(epsilon)(t) depends on a parameter epsilon, beta(epsilon)(t) -> 0. We will prove, under suitable assumptions, local and global well-posedness (using the uniform sectorial operators theory), the existence and regularity of pullback attractors {A(epsilon)(t) : t is an element of R}, uniform bounds for these pullback attractors, characterization of these pullback attractors and their upper and lower semicontinuity at epsilon = 0. (C) 2010 Elsevier Ltd. All rights reserved.

Existence of pullback attractors for pullback asymptotically compact processes

This paper is concerned with the existence of pullback attractors for evolution processes. Our aim is to provide results that extend the following results for autonomous evolution processes (semigroups) (i) An autonomous evolution process which is bounded, dissipative and asymptotically compact has a global attractor. (ii) An autonomous evolution process which is bounded, point dissipative and asymptotically compact has a global attractor. The extension of such results requires the introduction of new concepts and brings up some important differences between the asymptotic properties of autonomous and non-autonomous evolution processes. An application to damped wave problem with non-autonomous damping is considered. (C) 2009 Elsevier Ltd. All rights reserved.

Existence of Solution for a Class of Quasilinear Systems

This paper proves the existence of nontrivial solution for a class of quasilinear systems oil bounded domains in R(N), N >= 2, whose nonlinearity has a double criticality. The proof is based oil a linking theorem without the Palais-Smale condition.

Existence of secondary bifurcations or isolas for PDEs

In this paper, we introduce a method to conclude about the existence of secondary bifurcations or isolas of steady state solutions for parameter dependent nonlinear partial differential equations. The technique combines the Global Bifurcation Theorem, knowledge about the non-existence of nontrivial steady state solutions at the zero parameter value and explicit information about the coexistence of multiple nontrivial steady states at a positive parameter value. We apply the method to the two-dimensional Swift-Hohenberg equation. (C) 2011 Elsevier Ltd. All rights reserved.

Existence of orthogonal geodesic chords on Riemannian manifolds with concave boundary and homeomorphic to the N-dimensional disk

In this paper we give a proof of the existence of an orthogonal geodesic chord on a Riemannian manifold homeomorphic to a closed disk and with concave boundary. This kind of study is motivated by the link (proved in Giambo et al. (2005) [8]) of the multiplicity problem with the famous Seifert conjecture (formulated in Seifert (1948) [1]) about multiple brake orbits for a class of Hamiltonian systems at a fixed energy level. (C) 2010 Elsevier Ltd. All rights reserved.

The romanticism of contemporary theory : institution, aesthetics, nihilism

"Justin Clemens presents a valuable study of the links between Romanticism and contemporary theory. The central contention of this book is that contemporary theory is still essentially Romantic - despite all its declarations to the contrary, and despite all its attempts to elude or exceed the limits bequeathed it by Romantic thought." "This study will be of interest to literary theorists, philosophers, political theorists, and cultural studies scholars."--BOOK JACKET.

Mitochondrial 12S rRNA sequences support the existence of a third species of freshwater blackfish (Percicthyidae: Gadopsis) from south-eastern Australia

Fish of the genus Gadopsis are a distinctive component of the freshwater fish fauna of south-eastern Australia. Gadopsis marmoratus and G. bispinosus are the only two species recognised within the genus, with the former of uncertain taxonomic status, as it is thought to be composed of at least two distinct geographical forms based on morphological and allozyme data. The objective of this study was to investigate DNA sequence divergence in Gadopsis, especially in the western portion of its distribution, using an approximately 400 base pair fragment of the mitochondrial small subunit 12S rRNA gene region in order to reassess the taxonomy of the genus. Individuals from 11 locations were sequenced and confirm that G. marmoratus and G. bispinosus are genetically distinct, and further that the G. marmoratus complex consists of two divergent clades representing the previously identified northern and southern forms. The degree of divergence between the three Gadopsis clades was similar (5–6% nucleotide substitutions), suggesting that they diverged from a common ancestor at approximately the same period in geological time. These results are consistent with previous allozyme studies and highlight the usefulness of mitochondrial DNA data coupled with allozyme information for clarifying taxonomic boundaries in morphologically conservative aquatic organisms.

Existence and design of reduced-order scalar functional observers

In the existing literature, the existence conditions and design procedures for scalar functional observers are available for the cases where the observers’ order p is either p=1 or p=(v-1), where v is the observability index of the matrix pair (C,A). Therefore, if an observer with an order p=1 does not exist, the other option is to use a high-order observer with p=(v-1). This paper provides the existence conditions and a design procedure for scalar functional observers of order 0≤p≤2, and demonstrates the presented results with a numerical example. where K, M, E, H and G are constant matrices to be designed. The problem of observing a scalar functional or multi functionals (z(t)∈Rk , k>1) of the state vector has been the subject of numerous papers, and different algorithms have been proposed (see, [1]-[13] and references therein). There are also papers that deal with the order reduction of multi-dimensional functional observers [9,10,12,13]. For scalar functional observers, a well-known Luenberger’s classic result [1] provides an upper bound on the order with p=(v-1). It is interesting to note here that, except for a recent result of Darouach [12,13], little results have been reported on the order reduction for scalar functional observers.

On the existence and design of functional observers for linear systems

Darouach [1] recently derived necessary and sufficient conditions for the existence and stability of functional observers with an order, p, equals to the dimension m of the vectors to be estimated. In general, these conditions are difficult to satisfy and when they are not, the only available option is to increase the order of the functional observers. This note presents new conditions for the existence of a general pth-order functional observer. Systematic procedures for the synthesis of reduced-order functional observers are given. A numerical example is given to illustrate the design procedures.

Resisting assimilation : the mild aesthetics and wild perceptions of the migrant house

The physical adaptation, remaking and maintenance, or building of the house plays a significant role in immigrants’ sense of belonging to a community, especially in contexts of first generation elderly immigrants with minimal English language skills. Psychoanalytic theories propose that objects are integral to a subject’s identity, but that the path of effect between the subject and object is not causal or direct, rather it goes via the unconscious. This paper seeks to examine the relationship between immigrants and their houses through these theories adapting them to an analysis of the houses. It draws its data from field research of three elderly immigrant households. The iconography of the house has always been perceived as central to the analysis of dreams, here the thesis is that the house is the most significant object of the immigrant because it mediates the many worlds inherent to the migrant’s imaginary landscapes. The analysis will seek to understand this role of the house.

Secondly, while many houses in which migrants live can barely be differentiated in clear physical ways from the typology of houses built in Australia, the perception that they are different is a strong myth. At the least it has resulted in very little, if any, study of this vernacular of new Australian houses. It would be easy to argue that to build a house in Australia is the most important mode of assimilation because a way of life is intrinsically set by this suburban paradigm. But for the reason of this perception of difference I will explore an idea about ethnic aesthetics as a mode of resisting assimilation. In writing on taste in his seminal book, Distinction, the sociologist, Pierre Bourdieu, has argued that taste is a way of classifying people into classes, race, culture, but it is also a way for dominant and ruling classes to resist challenges from other parties, and maintain a particular hierarchy of society. In this case those other parties are ethnic communities in Australia whose tastes are not always the same as that of the dominant Anglo-Celtic community.

The existence and nature of risk management committees in Australian companies

A risk management committee (RMC), as a newly evolving sub-committee of the board of directors, functions as a key governance support mechanism in the oversight an organisation’s risk management strategies, policies and processes. However, empirical evidence on the factors associated with the existence and the type of RMCs remains scant. Using an agency theory perspective, this study investigates the association between board factors such as proportion of non-executive directors, CEO duality, and board size; as well as, other firm-related factors (e.g. auditor type, industry, leverage, and complexity), and (1) the existence of a RMC, and (2) the type of RMC (namely, a separate RMC versus one that is combined with the audit committee). Data was collected from the annual reports of the top 300 ASX-listed companies. The results, based on logistic regression analyses, indicate that RMCs tend to exist in companies with an independent board chairman and larger boards. Further, the results also indicate that in comparison to companies with a combined RMC and audit committee, those with a separate RMC are more likely to have larger boards, higher financial reporting risk and lower organisational complexity. The findings of this study provide additional information on the use and design of RMCs in a voluntary setting.

Kerry Freedman's Teaching visual culture : curriculum, aesthetics and the social life of Art

Teaching Visual Culture: Curriculum, Aesthetics and the Social Life of Art, Kerry Freedman (2003) New York: Teachers College Press & Reston: National Art Education Association, xiv + 187 pp., ISBN 0-8077-4372-0 (hbk £29.95)

This critical review has two principal goals. First of all, it will briefly summarize how Kerry Freedman’s ambitious eight-chapter monograph initially sets in train a number of key themes, all of which are aimed at enlarging if not transforming visual arts practice. Secondly, it will critically disclose a small set of pivotal assumptions which call any uncritical support for visual culture as the panacea for arts education into question. More particularly, we shall conclude, the logical underpinnings of Teaching Visual Culture are open to serious doubt in at least two respects.

Kristevan aesthetics, performativity and the production of situated knowledge

In this paper, I will draw on the work of Julia Kristeva to argue that performativity can be understood in terms of a materialist ontology that underpins creative production and the knowing subject. To understand this, we need to examine the relationship between individual history, biology and culture and processes through which creative practice attributes value by translating psychic representations of affect and drive into verbal and visual signs. Kristeva's aesthetics does not plunge us into an obscure metaphysics, but provides a model for articulating material-discursive practices that emerge from corporeal responses. Enactments, predicated by desire give rise to agency and judgement allowing practice to test theory through the production of situated knowledge.

Kristeva's psychoanalytical position reveals the necessity of linking material and individual practices of art with the social through language and interpretation. Material-discursive practices can only acquire meaning through their relationship between the speaking subject and addressees. Art itself provides us with the means for discovering the knowledge it produces. In and through material practice, the work of art is capable of transferring back to the artist as viewer, structures of meaning that have hitherto been hidden. In practice, this involves a constant movement between the biological self (the self as 'other') and the social self, the ego. In artistic research, it can be said that the first addressee is the artist her/himself, as social other. Constant movement between the two in creative practice can thus be understood as a performative production of knowledge.