Higher-order non-linear analysis of steel structures. Part I : elastic second-order formulation

This paper presents a higher-order beam-column formulation that can capture the geometrically non-linear behaviour of steel framed structures which contain a multiplicity of slender members. Despite advances in computational frame software, analyses of large frames can still be problematic from a numerical standpoint and so the intent of the paper is to fulfil a need for versatile, reliable and efficient non-linear analysis of general steel framed structures with very many members. Following a comprehensive review of numerical frame analysis techniques, a fourth-order element is derived and implemented in an updated Lagrangian formulation, and it is able to predict flexural buckling, snap-through buckling and large displacement post-buckling behaviour of typical structures whose responses have been reported by independent researchers. The solutions are shown to be efficacious in terms of a balance of accuracy and computational expediency. The higher-order element forms a basis for augmenting the geometrically non-linear approach with material non-linearity through the refined plastic hinge methodology described in the companion paper.

Higher-order non-linear analysis of steel structures. Part II : refined plastic hinge formulation

In the companion paper, a fourth-order element formulation in an updated Lagrangian formulation was presented to handle geometric non-linearities. The formulation of the present paper extends this to include material non-linearity by proposing a refined plastic hinge approach to analyse large steel framed structures with many members, for which contemporary algorithms based on the plastic zone approach can be problematic computationally. This concept is an advancement of conventional plastic hinge approaches, as the refined plastic hinge technique allows for gradual yielding, being recognized as distributed plasticity across the element section, a condition of full plasticity, as well as including strain hardening. It is founded on interaction yield surfaces specified analytically in terms of force resultants, and achieves accurate and rapid convergence for large frames for which geometric and material non-linearity are significant. The solutions are shown to be efficacious in terms of a balance of accuracy and computational expediency. In addition to the numerical efficiency, the present versatile approach is able to capture different kinds of material and geometric non-linearities on general applications of steel structures, and thereby it offers an efficacious and accurate means of assessing non-linear behaviour of the structures for engineering practice.

Second-order elastic finite element analysis of steel structures using a single element per member

Finite element frame analysis programs targeted for design office application necessitate algorithms which can deliver reliable numerical convergence in a practical timeframe with comparable degrees of accuracy, and a highly desirable attribute is the use of a single element per member to reduce computational storage, as well as data preparation and the interpretation of the results. To this end, a higher-order finite element method including geometric non-linearity is addressed in the paper for the analysis of elastic frames for which a single element is used to model each member. The geometric non-linearity in the structure is handled using an updated Lagrangian formulation, which takes the effects of the large translations and rotations that occur at the joints into consideration by accumulating their nodal coordinates. Rigid body movements are eliminated from the local member load-displacement relationship for which the total secant stiffness is formulated for evaluating the large member deformations of an element. The influences of the axial force on the member stiffness and the changes in the member chord length are taken into account using a modified bowing function which is formulated in the total secant stiffness relationship, for which the coupling of the axial strain and flexural bowing is included. The accuracy and efficiency of the technique is verified by comparisons with a number of plane and spatial structures, whose structural response has been reported in independent studies.

Direct second-order elastic analysis for steel frame design

The traditional structural design procedure, especially for the large-scale and complex structures, is time consuming and inefficient. This is due primarily to the fact that the traditional design takes the second-order effects indirectly by virtue of design specifications for every member instead of system analysis for a whole structure. Consequently, the complicated and tedious design procedures are inevitably necessary to consider the second-order effects for the member level in design specification. They are twofold in general: 1) Flexural buckling due to P-d effect, i.e. effective length. 2) Sway effect due to P-D effect, i.e. magnification factor. In this study, a new system design concept based on the second-order elastic analysis is presented, in which the second-order effects are taken into account directly in the system analysis, and also to avoid the tedious member-by-member stability check. The plastic design on the basis of this integrated method of direct approach is ignored in this paper for simplicity and clarity, as the only emphasis is placed on the difference between the second-order elastic limit-state design and present system design approach. A practical design example, a 57m-span dome steel skylight structure, is used to demonstrate the efficiency and effectiveness of the proposed approach. This skylight structure is also designed by the traditional design approach BS5950-2000 for comparison on which the emphasis of aforementioned P-d and P-D effects is placed.

The serious and playful work of gender : talk and social order in a preschool classroom

This chapter reports some observations made of the social interactions of girls and boys, aged 3 to 5 years, in play situations in a preschool classroom of a childcare centre. It provides an alternate framework for early childhood educators to become aware of how preschool children construct their gendered social organizations. As girls and boys organise and build their social worlds of play through their talk-in-interaction, they are building their social orders. In this chapter, an analysis of one episode of children's play has, as its focus , the methods that some girls and boys use in their talk and activity to make sense of their everyday interactions. The analysis of play shows the children's real life work of constructing and maintaining gendered social orders in their lived everyday social worlds. A close reading of the transcript of an episode illustrates how two girls turn they boys' masculine practices o ritualized threats into performance. By so doing, they show that while they know masculine discourse, and can perform it themselves, they do not actually 'own' it in the same way that the boys do. In this way, gender is established not as a social density but as a shaped dynamic practice that is ongoing, build by relational encounters and shaped by the collective performances of the participants.

The Use of Ecological Design to Achieve Sustainable Development in Queensland, Australia

This series of technical papers arose out of the action by a private entrepreneur to initiate a process beyond mere regulatory compliance in order to achieve best environmental practice at proposed large new visitor gateways to Australia’s Great Barrier Reef. Because of the complexity of issues involved at such urbanized downstream sites, the range of topics covered is wide – though still only those considered at this juncture to be of management priority. Included on this platform is one introductory paper reviewing the history of environmental management in the field in Queensland, and three papers which seek to appreciate the main techniques by which government contributes to the solutions viz. through the national park, threatened species list, and environmental impact assessment. The history paper was designed to allow the present series to be considered in broad context as well as performance to date. The work emphasizes that much of the fertile land that must be sustained nowadays lies in the province of the private sector, and that the initiative to create any new cost-effective paradigm in ecologically-sustainable practices lies mostly in their hands. In all instances, this strategic approach to large-scale property planning is through ecological design – using field case studies around the immediate biophysical catchment of the development, with attendant focus on the associated legal catchment (the actual development site) and the social catchment (the effective land managers). The first of these has given rise to a document termed a Regional Landscape Strategy, its implementation planned in concert with an Environmental Impact Assessment of the site and with a Strategic Regional Initiative (still being tested in the field) for community engagement. The first document takes into account the aspirations of government as expressed in its broad-scale regional plans.

Sentencing policy : the politics of law and order

Against the advice of their own parliamentary committees, and despite the experience of other jurisdictions, both the Government and Opposition parties seem to be intent on outbidding each other on mandatory sentencing regimes in the lead-up to the 2003 NSW election, says DAVID BROWN.

Shadow boxing with an imaginary enemy : a response to “law and order blues”

In our rejoinder to Don Weatherburn's paper, “Law and Order Blues”, we do not take issue with his advocacy of the need to take crime seriously and to foster a more rational approach to the problems it poses. Where differences do emerge is (1) with his claim that he is willing to do so whilst we (in our different ways) are not; and (2) on the question of what this involves. Of particular concern is the way in which his argument proceeds by a combination of simple misrepresentation of the positions it seeks to disparage, and silence concerning issues of real substance where intellectual debate and exchange would be welcome and useful. Our paper challenges, in turn, the misrepresentation of Indermaur's analysis of trends in violent crime, the misrepresentation of Hogg and Brown's Rethinking Law and Order, the misrepresentation of the findings of some of the research into the effectiveness of punitive policies and the silence on sexual assault in “Law and Order Blues”. We suggest that his silence on sexual assault reflects a more widespread unwillingness to acknowledge the methodological problems that arise in the measurement of crime because such problems severely limit the extent to which confident assertions can be made about prevalence and trends.

Mandatory sentencing : a criminological perspective

This paper will give a ‘criminological perspective’ on mandatory sentencing. It will however largely avoid the issues of the effect of mandatory sentencing provisions on the judicial process and judicial independence, as this has already been covered by Sir Anthony Mason. It will also avoid the legal issues concerning the constitutional, human rights and international law aspects of mandatory sentencing which will be covered by later speakers. The aim will be to give a brief overview of research which evaluates the effects of mandatory sentencing provisions in terms of the available evidence of whether they meet their stated aims of deterrence, selective incapacitation and the reduction of crime rates. This will be done in two parts, first in relation to the more extensive experiment in mandatory sentencing in the USA which has provided some of the impetus and metaphors ("three strikes") for recent Australian developments; and second the recent mandatory sentencing provisions in Western Australia (WA) and the Northern Territory (NT). Evidence from both the US and WA (NT is hard to assess because of the lack of proper monitoring and criminal statistics) indicates that mandatory sentencing does not produce the effects of deterrence, selective incapacitation and crime reduction which are its stated justifications and does produce a range of damaging side effects in terms of distortion of the judicial process, wildly disproportionate sentencing, additional financial and social cost and deepening social exclusion of individuals and particular communities. So what is left are the less acknowledged underpinnings of mandatory sentencing in the form of the symbolic politics of law and order, the politics of social exclusion and a displacement of racial anxieties and hostilities onto the terrain of the legal. In fashioning this necessarily brief overview a number of sources have been heavily drawn upon, in particular the excellent work by Neil Morgan from UWA (Morgan, 1995;1999; 2000); Dianne Johnson and George Zdenkowski in their detailed report to the Senate Inquiry (2000); and a number of articles appearing in 1999 in an excellent special issue of the UNSW Law Journal, all of which are highly recommended for further reading.

The Chidiac case : another miscarriage of justice?

On 25 March 1997 the Witness program on Channel 7 screened a story about the conviction of Neil Chidiac in February 1989 for conspiracy to import a trafficable quantity of heroin in NSW. The program questioned the justice of Chidiac's conviction and filmed his recent release from prison on parole after serving over eight years in prison, still protesting his innocence. Witness featured an interview with the chief Crown witness against Chidiac, Alfred Oti, in which Oti completely repudiated the testimony he gave at the trial and admitted to lying at the behest of the police in order to secure advantages for himself...

Molecular characterization of "Candidatus Parilichlamydia carangidicola," a novel Chlamydia-like epitheliocystis agent in yellowtail kingfish, Seriola lalandi (Valenciennes), and the proposal of a new family, "Candidatus Parilichlamydiaceae" fam. nov. (order Chlamydiales).

Three cohorts of farmed yellowtail kingfish (Seriola lalandi) from South Australia were examined for Chlamydia-like organisms associated with epitheliocystis. To characterize the bacteria, 38 gill samples were processed for histopathology, electron microscopy, and 16S rRNA amplification, sequencing, and phylogenetic analysis. Microscopically, the presence of membrane-enclosed cysts was observed within the gill lamellae. Also observed was hyperplasia of the epithelial cells with cytoplasmic vacuolization and fusion of the gill lamellae. Transmission electron microscopy revealed morphological features of the reticulate and intermediate bodies typical of members of the order Chlamydiales. A novel 1,393-bp 16S chlamydial rRNA sequence was amplified from gill DNA extracted from fish in all cohorts over a 3-year period that corresponded to the 16S rRNA sequence amplified directly from laser-dissected cysts. This sequence was only 87% similar to the reported "Candidatus Piscichlamydia salmonis" (AY462244) from Atlantic salmon and Arctic charr. Phylogenetic analysis of this sequence against 35 Chlamydia and Chlamydia-like bacteria revealed that this novel bacterium belongs to an undescribed family lineage in the order Chlamydiales. Based on these observations, we propose this bacterium of yellowtail kingfish be known as "Candidatus Parilichlamydia carangidicola" and that the new family be known as "Candidatus Parilichlamydiaceae."

Sequencing risk : the worst returns in their worst order

For the first of the baby boomers turning 65 years of age, after a decade littered with financial shocks (dot.com bubble, sub-prime, global financial crisis, sovereign debt), sequencing risk can represent a significant threat to their retirement nest eggs. This paper takes an outcomeoriented approach to the problem, to provide practical insights into how sequencing risk works and the critical dependency of retirement outcomes on sequencing risk. Our analysis challenges the conventional wisdom that it is the accumulated average of investment returns that matter. We show, instead, that it is the realised sequence of returns which largely determines the sustainability of retirement incomes.

The return of the mail-order bridegroom

Co-producer of this contemporary music album.