bluuebunny/crossref_metadata_2025 huggingface dataset:
Transforming the City: People, Property and Identity in Millennial Auckland
Authors: MURPHY LAURENCE , FRIESEN WARDLOW , KEARNS ROBIN A.
Published: May 2008

Developing on the ‘global’ and ‘postmodern’ cities literatures, this paper sets out a research agenda for exploring the nature of urban transformation in contemporary Auckland. Focusing on the recursive relationship between global and local processes, we examine emerging socio‐demographic and cultural processes at work in the city. Our research agenda addresses three themes: emerging ethnoscapes, the creation and reproduction of residential landscapes, and the examination of consumption sites and practices.
Agricultural Restructuring and Response: Inter‐relationships Between Farm Adjustment Strategies in Waihemo, 1984–1997
Authors: JOHNSEN SARAH
Published: May 2008

Farm households in New Zealand have responded to the changing political and economic environment since the mid‐1980s in a variety of ways. This paper explores the various farm adjustment strategies adopted by farm households in Waihemo (East Otago) and ways in which these influence both the household and enterprise domains of the family farm unit. It examines the complex interrelationships between specific farm adjustments, drawing attention to the ways in which these are redefining the nature of family farming in the area.
Rationalising Hospital Services: Reflections on Hospital Restructuring and its Impacts in New Zealand
Authors: ROSSBARNETT J.
Published: May 2008

This paper investigates recent patterns of hospital restructuring in New Zealand and discusses the extent to which emerging forms of governance and changes in hospital provision conform to Jessop's (1994) idea of the ‘hollowed out’ state. The paper places the 1993 reforms within their historical context and examines processes of decentralisation, downsizing, privatisation and cost shifting within the hospital sector. It concludes with a discussion of some of the implications of hospital restructuring for regions, communities and their medical care providers and lays out some of the key questions which should rank high on the geographical research agenda.
Dealing with Ambiguity: On the Interdependence of Change in Agriculture and Rural Communities
Authors: JOSEPH ALUNE , UDGARD JACQUELINE M. , BEDFORD RICHARD
Published: May 2008

The well‐established linkages between the fortunes of agriculture and rural communities that have characterised the histories of rural areas in New Zealand and elsewhere have been severely challenged over the past two decades. Some commentators have posited a de‐coupling of the two sectors. This paper explores evolving farm and rural community interactions in New Zealand, first with reference to a descriptive model and second with reference to the lived experiences of rural residents in two Central North Island communities, Taumarunui and Tirau. The key finding from the research is that the distinction between de‐coupling and re‐linking while conceptually appealing is empirically problematic as observed trends suggest a complex and ambiguous mixture of both.
2001: Reflections on the Spatial Odysseys of New Zealanders
Authors: BEDFORD RICHARD
Published: May 2008

‘Brain drain’ has been one of the abiding topics of public debate during 2000. Emigration of New Zealanders much more than immigration of new settlers has dominated discourses about international migration, even though for much of the year the country experienced overall net migration gains rather than net losses. This paper addresses the migration of New Zealanders with reference to both the international shortage of skilled labour, especially ‘white’ English speaking labour, and the growing debate about ‘replacement’ migration. The gradual recognition, both by politicians and academics, of a ‘New Zealand diaspora’ is examined.
Ecological Crises or Marginal Disruptions: the Effects of the First Humans on Pacific Islands
Authors: NUNN PATRICK D.
Published: May 2008

There is considerable debate concerning the effects of the first humans on the environments of the Pacific Islands. Much disagreement has arisen because of the differing techniques used to fix the time when the first humans arrived on particular islands. There is also considerable discussion about how stable, at a variety of timescales, Pacific Island environments were in the absence (or presence) of humans. John Flenley has proposed that archaeological dates significantly underestimate the times of initial human arrival on many Pacific Islands, the most accurate estimates of which come from palynological analyses. This paper offers some support to this view, from consideration of reef‐growth hiatuses in Fiji, yet doubts that initial human arrivals were coincident with ecological crises. There is considerable evidence that natural climate changes, particularly short‐term ones, caused major ecological and environmental disruptions on Pacific Islands, during both their pre‐ and post‐settlement histories, and that human arrival was marked in most cases by only marginal disruptions.
Fragmented Urban Spaces? Ethnic Residential Areas in New Zealand Cities, 1996
Authors: JOHNSTON RON , POULSEN MICHAEL , FORREST JAMES
Published: May 2008

Residential segregation of ethnic groups is a major feature of cities in multi‐cultural societies such as New Zealand's. Measuring the degree of segregation has been the focus of much attention over the last half century, but there are difficulties with comparative studies using most of the measures adopted. An alternative procedure which classifies residential areas according to a homogeneity‐heterogeneity continuum is applied here to 1996 census small‐scale data for each of New Zealand's 33 main urban areas, to identify the degree of segregation of various ethnic groups. It reports that most New Zealanders from all ethnic groups (defined by self‐identity) live in mixed rather than exclusive residential areas. The main ethnic enclaves/ghettos are occupied by Maori and Pacific Islanders, and are entirely concentrated in the North Island, especially in urban areas which have substantial Polynesian populations.
Revitalising Local Economic Development‐New Zealand Policy and Practice
Authors: MANSVELT JULIANA
Published: May 2008

In common with many other advanced capitalist nations, the rolling back of the state in New Zealand has seen a decline in direct state intervention in heal and regional economies. Yet since 2000 the current Labour Coalition Government has sought to promote a renaissance in economic development at local and regional scales. A survey of New Zealand territorial local authorities indicates involvement in heal economic development (LED) is a recent phenomenon involving facilitation of outside agencies which is orientated toward tourist, advisory and promotional activities. The implications of these findings for future research in an environment of ‘revitalised’ policy and practice in the New Zealand context is explored.
Measuring and Reporting Changing Public Access to and Along the Coast
Authors: CLARK E L , HILTON M J
Published: May 2008

Public access to and along the coast is identified as a matter of national importance in the Resource Management Act 1991. Despite this, few local authorities have started to monitor public access to and along the coast. The adoption of two indicators of public coastal access by the Ministry for the Environment deserves closer analysis ‐ how can local authorities implement those indicators as part of their section 35 responsibilities? Research carried out in Otago in 1999 examined the effectiveness of five indicators of public coastal access. This research concluded that one of the Ministry's indicators is a good measure of public access, but it could be extended to include other factors that influence public access.
Globalisation and New Zealand: Anchoring the Leviathan in a Regional Context
Authors: BARAGWANATH LUCY , MCALOON JIM , PERKINS HARVEY
Published: May 2008

Despite its ambiguity and contentiousness, the term globalisation is widely used in New Zealand, as it is elsewhere, in analyses of contemporary times. Yet the concept of globalisation is frequently invoked at a high level of generality with little consideration of the specificities of the particular contexts to which it is applied; and in the case of New Zealand, the notion seems incongruous in many respects. We therefore seek to anchor the notion in the regional context of Canterbury, where our historical and ethnographic research leads us to suggest that globalisation is a misleading and contentious description of contemporary New Zealand. As a set of discourses, however, globalisation is pervasive and powerful. The contemporary policy climate strongly reflects the hegemonic discourse of hyperglobalism, which emphasises generic globality, novelty and change at the expense of continuity and the particularity of place, limiting the possibilities for action. Thus while empirically, many parallels with the past persist, nevertheless, contemporary policy‐makers understand New Zealand's options as determined by globalisation as an external force. This contrasts with past policy discourses which emphasised the scope for domestic decision‐making, within the context of inextricable connections with the outside world. Our emphasis on the discursive construction of the globalisation imperative draws attention to possible alternative interpretations of New Zealand's contemporary options.
Realistic Sustainability? Urban Transport Planning in Wellington, New Zealand
Authors: DODSON JAGO , MEES PAUL
Published: May 2008

Urban transport systems have key roles in supporting environmental sustainability. New Zealand's transport planning arrangements are promoted as a model by agencies such as the World Bank. This paper explores the New Zealand transport planning framework using a case study of the Wellington region's strategic balancing of transport modes and projects. The paper argues that despite some positive rhetoric, concerns about the sustainability of transport planning in Wellington remain. The paper concludes by discussing the need to reassess New Zealand's national framework, and identifies some directions for reform.
Mudslides Developed on Waitemata Group Rocks, Tawharanui Peninsula, North Auckland
Authors: MOON VICKI , LANGE ANDREW DE , LANGE WILLEM DE
Published: May 2008

On Tawharanui Peninsula mudslides occur in soils developed on Waitemata Group flysch similar to that underlying much of the Auckland metropolitan area. Mudslides are shallow soil failures with a bowlshaped source area, an elongated track, and an accumulation zone. Movement may continue for decades to centuries. Modelling suggests that failure of saturated soils occurs along a basal surface defined by the regolith / bedrock contact; rates of movement and time of initiation have not been established. Reactivation or increased mobility of mudslides due to climatic change represents an increased hazard for infrastructure in Auckland City.
Moved by the Company ‐ International Migrants and Transnational Organisations
Authors: PERRY MARTIN
Published: May 2008

Labour markets are generally thought to have become more integrated across international boundaries. Employees that move between branches of transnational organisations are a potential contributor to this integration. Interviews with human resources managers in 33 New Zealand‐based organisations indicate that the number of employees transferred is small and likely to decrease as corporate functions are transferred from New Zealand to regional offices.
Surface Moisture Availability and Rock Weathering in Cold Climates
Authors: Elliott Christine
Published: May 2008

The importance of moisture in determining which rock weathering processes may operate, as well as the rate at which rock weathering occurs, has long been recognised. However, little is known about how often or when moisture is available to the rock surface, or for how long the surface may be wetted. This paper gives some initial results from current research on granite rocks in Antarctica. Recordings of surface moisture, for two aspects and three locations in Victoria Land, show that moisture reaches the rock surface more frequently than might initially have been expected in this dry climate. The number of occasions the surface is wetted, and the quantity of moisture the surface received, varied with aspect and time of year. Rock surfaces could be wet for up to 40% of the time during the summer months. This has important implications for rock weathering where some processes are deemed not to operate, or to operate in very restricted locations, due to the apparent absence of moisture.
(Trans)national Bodies, (Trans)national Languages and the Transformation of Local Urban Space
Authors: Collins Francis Leo
Published: May 2008

This paper discusses some of the ways that international students, particularly those from East Asia, are involved in the transformation of urban space in Auckland City. Using existing economic reports, local media accounts and the author's initial observations, the paper identifies how the embodied and linguistic practices of international students are involved in the changing landscapes of Auckland's inner city. This cursory reading serves to identify a research agenda and to reflect upon some key theoretical textxs. The insights of Arjun Appadurai, Michael Peter Smith and Ulrich Beck are used to suggest that the changes in Auckland, whilst certainly local, are also influenced fry factors that emerge from beyond the borders of international students' origin communities, cities and nations.
Placing Geographical Imagination in Film: New Zealand Filmmakers' Use of Landscape
Authors: Heron Erena Le
Published: May 2008

The paper explores the role of landscape in New Zealand films. How is the New Zealand landscape imagined and revealed? What kind of landscape do filmmakers present? I argue that New Zealand filmmakers tap into specific geographical imaginations when they make films, and that this results in certain kinds of landscapes being produced. I sketch the methodology used in a survey of New Zealand films and ‘read’ a selection of opening and closing sequences and ‘generic places’ found in a selection of contemporary New Zealand films. 1 then offer some conclusions about New Zealand films, and their production, portrayal and imagining of New Zealand.
Downstream Fining and Sorting of Gravel Clasts in the Braided Rivers of mid‐Canterbury, New Zealand
Authors: Browne Greg
Published: May 2008

Gravel clast size dimensions have been determined in the Rakaia, Ashburton, and Rangitata rivers by measuring 100 clasts at representative sample locations along each river. In all rivers, gravel size decreases and sorting improves downstream for mean, D50, and D90 fractions of the bed material. Clast size entering the sea is similar in all rivers (30–40 mm b‐axis dimension), despite large variations in transport distance, input size of clasts at their gorges, and discharge. The greatest size reduction occurs in the Rangitata River which has the shortest transport distance and steepest gradient. Rates of downstream clast size reduction are greater than would be assumed from Sternberg's Law, suggesting that additional factors, other than physical abrasion, such as sorting and selective entrainment operate.
Restructuring Governance of New Zealand Seaports: Geographical Impacts of Corporatisation
Authors: Memon Ali , Milne Markus J. , Selsky John W.
Published: May 2008

This study examines the rationales for and geographical outcomes of the post 1988 changes in port governance in New Zealand and their implications from a policy perspective. The study offers insights into the interrelationship between global processes and local places in the context of economic deregulation, a devolved infrastructure planning mandate and intra‐industry competitive dynamics. A trend towards port concentration consequent on globalisation has been long recognised in the international literature. In New Zealand, the trend towards port concentration can be described as selective, limited primarily to import trade while export trade is more dispersed. This new port geography is part of wider political and socio‐economic development geographies of the national and global hinterlands and forelands these ports interact with.
The Elusive AD 1826 Tsunami, South Westland, New Zealand
Authors: Wells James R. Gofr Andrew , Chagué‐Goff Catherine , Nichol Scott L. , Devoy Robert J.N.
Published: May 2008

In AD 1826 sealers reported earthquake and tsunami activity in Fiordland, although, contemporary or near‐contemporary accounts of tsunami inundation at the time are elusive. A detailed analysis of recent sediments from Okarito Lagoon builds on contextual evidence provided by earlier research concerning past tsunami inundation. Sedimentological, geochemical, micropalaeontological and geochronological data are used to determine palaeoenvironments before, during and after what was most probably tsunami inundation in AD 1826. The most compelling chronological control is provided fry a young cohort of trees growing on a raised shoreline bench stranded fry a drop in the lagoon water level following tsunami inundation.
‘Limited Employment Areas’: Striating the Spaces of Unemployment in New Zealand
Authors: Henry Matthew
Published: May 2008

This paper examines the recent policy announced by the Minister of Social Development that identifies a series of ‘Limited Employment Areas’ within which access to the unemployment benefit would be restricted. Drawing on Deleuze's ideas of striation and modulation the paper explores the intersection of governance, space, and risk that seems to be combined in the policy. The paper concludes by reflecting on the deployment of risk based on ontological claims about the spatiality of unemployment. In seeking to shape the decisions of benefit seekers, there seems to be an emerging mosaic of welfare provision as a direct consequence of governmental intent, rather than as a failure of governmental ability.
Psychometric Evaluation of the Child‐Adolescent Teasing Scale
Authors: Vessey Judith A. , Horowitz June A. , Carlson Karen L. , Duffy Mary
Published: May 2008

Background:  This article presents the psychometric evaluation of the Child‐Adolescent Teasing Scale (CATS), an instrument to be used as a screening measure with middle school students.

Methods:  A 70‐item scale was initially derived from qualitative data obtained from focus groups comprised of middle school students. A diverse sample of participants (N = 764) then completed the CATS and the Piers‐Harris Children’s Self‐Concept Scale (PHCSCS); their mothers completed the Pediatric Symptom Checklist (PSC) and a demographic information form. A psychometric sample (N = 666) without missing data was used for subsequent analyses.

Results:  Principal components analysis resulted in a 32‐item, 4‐factor solution: Personality & Behavior Teasing (14 items), Family & Environment Teasing (7 items), School‐Related Teasing (9 items), and Teasing About My Body (2 items). The standardized Cronbach’s alpha for the final version was .94 and ranged from .83 to .90 for the subscales. The CATS’s content validity, initially ascertained a priori by experts, was re‐reviewed upon the instrument’s refinement and supported. One‐tailed t tests of mean differences between low‐ and high‐scoring CATS groups on the PSC (t=−3.41, p < .03) and the PHCSCS (t=−11.39, p < .001) and supported the CATS’s criterion‐related validity.

Conclusions:  The 4‐factor, 32‐item CATS is psychometrically defensible and has demonstrated potential as a screening measure to identify students who are at risk from distressing teasing.
Molecular Modeling and Docking Analysis of Entamoeba histolytica Glyceraldehyde‐3 Phosphate Dehydrogenase, A Potential Target Enzyme for Anti‐Protozoal Drug Development
Authors: Singh Shailza , Malik Balwant Kishen , Sharma Durlabh Kumar
Published: May 2008

The enzymes of the glycolytic pathway constitute an excellent target for the design of new anti‐protozoal agents; glyceraldehyde‐3 phosphate dehydrogenase catalyzes the reversible oxidative phosphorylation of d‐glyceraldehyde 3‐phosphate (GAP) into d‐glycerate 1,3‐bisphosphate (1,3‐diPG) in the presence of NAD(+) and inorganic phosphate (P(i)). The prediction of three‐dimensional structure of Entamoeba histolytica and the docking of the coumarins were performed using the crystal structure of glyceraldehyde‐3 phosphate dehydrogenase from Leishmania mexicana as template. Energy minimization of the whole complex showed, as expected, that most of the template interactions are preserved in the Entamoeba structure, except for SER178, ARG220 and THR167. However, novel interactions involving ILE 193 and THR 173 were also observed.
‘Naturalism’ and ‘Skepticism’ in Hume'sTreatise of Human Nature
Authors: Greenberg Sean
Published: May 2008

Hume begins theTreatise of Human Natureby announcing the goal of developing a science of man; by the end of Book 1 of theTreatise, the science of man seems to founder in doubt. Underlying the tension between Hume's constructive ambition – his ‘naturalism’– and his doubts about that ambition – his ‘skepticism’– is the question of whether Hume is justified in continuing his philosophical project. In this paper, I explain how this question emerges in the final section of Book 1 of theTreatise, the ‘Conclusion of this Book’, then examine Janet Broughton's and Don Garrett's answers to it, and conclude by sketching a different approach to this question.
The nature of a financial investment intermediary's duty to his client
Authors: Chiu Iris H-Y
Published: May 2008

The landscape of legal duties imposed on financial investment intermediaries is characterised by the imposition of regulatory duties as well as duties arising under general law, in the realms of fiduciary duties and duties of care and skill. This article examines the relationship between public regulation and general private law in providing legal principles governing the conduct of financial investment intermediaries. This article also inquires into whether, in light of the Financial Services Authority's (FSA) desire to move into higher level ‘principles-based’ regulation of financial investment intermediaries, there may be a set of unifying principles that could govern financial investment intermediaries' relationships with their clients.
Bricolage and low cunning: Rorty on pragmatism, politics and poetic justice
Authors: Ward Ian
Published: May 2008

Richard Rorty died in June 2007. According to some he was the most interesting, perhaps even the most important, philosopher of his generation. His influence on legal theory, especially legal theory of the more critical and literary kind, was considerable. And yet, in comparison with his reputation in the philosophical and literary academy, for many legal academics Rorty remains a relatively hazy figure. The purpose of this paper is to provide an introduction to Rorty; to his broader philosophy of pragmatism, a philosophy as he termed it of ‘bricolage’ and ‘law cunning’, as well as to his writings which focused rather more closely on jurisprudential questions, most importantly those that addressed the nature of rights. It closes with some thoughts on Rorty's final, provocative, and timely, observations on the decline of American civil society. If lawyers and legal theorists have, in large part, neglected Rorty, it is unfortunate; for, in our present age of vaulting political pretence, rarely has the need for a strong measure of intellectual scepticism seemed to be more urgent.
Vibroacoustical Analysis Based on a Multimodal Strategy: Triple Modal Synthesis
Authors: Besset Sébastien , Jézéquel Louis
Published: May 2008

Modal synthesis methods have long been studied because the use of generalized coordinates makes it possible to reduce calculation costs. Our approach uses modes to describe each part of the assembly of several substructures, coupled with a fluid cavity. In a previous paper, we explained that ω2 developments could be used to minimize modal truncation. In the present paper, we consider a fluid-structure coupled system using a method called “triple modal synthesis.” High order developments will be made to describe the fluid part. First, two kinds of formulation will be explained: in displacement and in force. Second, calculation using finite element methods will be processed.
Design of Disturbance Observers for Multi-Input Multi-Output Systems
Authors: Shahruz S. M.
Published: May 2008

In this paper, the long-standing problem of designing disturbance observers for multi-input multi-output (MIMO) systems is solved. The disturbance observer presented here has a simple structure equivalent to that of the internal model control (IMC), thereby there is no need for the system inversion. Techniques to design the proposed disturbance observer are given. Furthermore, the design procedure is illustrated via examples for different MIMO systems.
On Failure Mechanisms in Flip Chip Assembly—Part 2: Optimal Underfill and Interconnecting Materials
Authors: Oh Yoonchan , Suh C. Steve , Sue Hung-Jue
Published: May 2008

The physics explored in this investigation enables short-time scale dynamic phenomenon to be correlated with package failure modes such as solder ball cracking and interlayer debond. It is found that although epoxy-based underfills with nanofillers are shown to be effective in alleviating thermal stresses and improving solder joint fatigue performance in thermal cycling tests of long-time scale, underfill material viscoelasticity is ineffective in attenuating short-time scale propagating shock waves. In addition, the inclusion of Cu interconnecting layers in flip chip area arrays is found to perform significantly better than Al layers in suppressing short-time scale effects. Results reported herein suggest that, if improved flip chip reliability is to be achieved, the compositions of all packaging constituent materials need be formulated to have well-defined short-time scale and long-time scale properties. Chip level circuit design layout also needs be optimized to either discourage or negate short-time wave propagation. The knowledge base established is generally applicable to high performance package configurations of small footprint and high clock speed. The approach along with the numerical procedures developed for the investigation can be a practical tool for realizing better device reliability and thus high manufacturing yield.
Fluid Dynamics Measurements and Numerical Simulations Around a Circular Cylinder Impinged by a Submerged Slot Jet of Air
Authors: Gori F. , Petracci I.
Published: May 2008

Submerged slot jets of air, impinging onto a cylinder, have been investigated with a new wind tunnel, which realizes low turbulence intensities at the slot exit. The hot anemometry has been used to measure velocity and turbulence across the section of the jet, at several distances from the slot exit, up to the impinged cylinder. The cylinder has been set at two distances from the slot exit, equal to 4 and 6 times the slot height. The Reynolds number of the jet is equal to 23,300, based on the hydraulic diameter of the slot.
On the Sign Convention in Thermodynamics: An Asset or an Evil?
Authors: Arnas A. O¨zer , Boettner Daisie D. , Bailey Margaret B.
Published: May 2008

In thermodynamics the sign convention normally used is energy added to a system in the form of heat is taken as positive and that added in the form of work is taken as negative – HIP to WIN (heat in positive – work in negative). This is a common sign convention although some texts specify that all forms of energy added to a system as heat or work are positive. However, regardless of the sign convention adopted for heat and work interactions, later in the same text the specified convention is abandoned in favor of magnitudes or absolute values. This occurs particularly in relation to cycle analyses in which the absolute value is used for energy transfers. Generally for reversible cycles there is no proof as to why the ratio of energy added/rejected via heat transfer equals the ratio of the absolute temperatures of the thermal reservoirs. To promote sign convention consistency, this paper develops the appropriate relationship between energy transfers and thermal reservoir temperatures for reversible cycles and applies the result to power producing and power consuming engineering devices.
On a Finger Model Actuated With Shape Memory Alloy Artificial Muscles
Authors: Chiroiu Veturia , Munteanu Ligia , Badea Traian , Nicolescu Cornel Mihai
Published: May 2008

The simulation of a flexible finger, actuated with the shape memory alloys (SMAs) artificial muscles, is presented in the paper. The finger is modeled as a cylindrically rod with three embedded NiTi wires in a n aluminum matrix. Forces between NiTi wires causes bending in any plane perpendicular to the longitudinal axis of the finger. The NiTi wires are heated above the austenitic start temperature by passing an electrical current, and the deflected wire tends to return to the initial configuration. Using characteristics of SMAs such as high damping capacity, super-elasticity, thermo-mechanical behavior and shape memory, the actuation for the finger is theoretically introduced and discussed.
On the Propagation and Coalescence of Delamination Cracks in Thermal Barrier Systems
Authors: Chen Xi
Published: May 2008

Coatings subject to residual compression eventually fail by buckle-driven delamination. The phenomenon is most vivid in thermal barrier coatings (TBCs) used in gas turbines. The failure evolution commences with the formation of a large number of small cracks at geometric imperfections near the interface. These cracks spread upon thermal exposure, particularly upon thermal cycling, because of the formation of a thermally grown oxide (TGO) beneath the TBC, which introduces normal and shear stress near the interface. Experimental observations indicate that some of these cracks coalesce to form large-scale delaminations susceptible to buckling. The mechanics governing crack coalescence and the consequent failure are addressed in the present analysis. A model is introduced that simulates stresses induced in the TBC by spatial variations in TGO growth. Energy release rates for cracks evolving in this stress field are determined. Two related scenarios are considered, which differ in the way the TGO shape evolves. In both, contact between the crack faces and the consequent wedging action is responsible for ultimate coalescence. The wedging force induces a mode I stress intensity that becomes infinite as the cracks coalesce. The consequence is that, for some TGO shapes, the energy release rate is always nonzero, with a minimum at a characteristic crack length. This minimum establishes a criterion for crack coalescence and failure. Based on these insights, finite element simulations have been used to predict cyclic crack growth rates in a TBC system that correlate well with experimental observations.
Analysis and Verifications for Meso-Scale Heat Exchanger With Magneto-Hydrodynamic (MHD) Pumps
Authors: Wang Pei-Jen , Chang Chia-Yuan
Published: May 2008

Electronic devices have been mainly relying on passive heat exchangers to transfer heat away for preventing catastrophic thermal runaway. However, the passive heat exchangers usually provide limited cooling capacity due to spatial limitations of the target systems. In this paper, an active heat exchanging system, based upon MHD pumping principle for driving electrically conducting coolant without utilizing mechanical moving-parts, was studied and experimentally verified. Governing equations of electrically conducting liquids driven by the Lorentz forces were derived by assuming steady state, incompressible and fully developed laminar flow conditions. Furthermore, numerical simulations were conducted with the explicit Finite-Difference Method to evaluate the performance of the heat exchanger. Finally, an experimental apparatus was built for measuring the flow velocity of coolant and the associated total cooling capacity. A significant flow velocity of 1.09 × 102 mm/s at 3 Ampere applied current was observed when the magnetic flux density was kept at 0.4 Tesla. The experimental results concluded that the heat exchanger consumed very low electric power; hence, the cooling system is very promising for applications in micro-fluidic systems.
Adaptive Vibration Control of Flexible Plate Structures With Actuator Placement Optimization
Authors: Peng Fujun , Ng Alfred , Hu Yan-Ru
Published: May 2008

This paper investigates piezoelectric actuator placement optimization on a rectangular plate structure and the vibration control of the structure. In the first part, an actuator placement optimization method is developed based on maximizing the controllability grammian. It is then implemented using Structuring Analysis in ANSYS Finite Element Analysis Package and Genetic Algorithm. In the second part, a filtered-x LMS-based multi-channel adaptive control is used to suppress vibration response of the plate. Numerical simulations are performed in suppressing tri-sinusoidal response at three points of the plates and the results show the control algorithm is efficient and robust in reducing the plate’s vibration. The results also demonstrate that the developed actuator placement optimization method is effective to reduce the energy required for achieving significant vibration reduction.
A Control-Oriented Polytropic Model of SI Engine Intake Manifold
Authors: Deur Josˇko , Hrovat Davor , Petric´ Josˇko , Sˇitum Zˇeljko
Published: May 2008

The paper presents experimental results which show significant changes of the intake manifold air temperature during fast tip-in/tip-out engine transients. An adequate two-state polytropic manifold model is developed and experimentally validated. An emphasis is on the derivation and parameterization of a time-variant structure of the heat transfer coefficient. The polytropic manifold model is extended to a three-state form for the more general case of different heat transfer properties for the manifold plenum and runners. An influence of the engine back flow on the runner thermal transients is observed. A simple extension of the three-state model with the back flow effect is proposed.
Physics-of-Failure HALT Result Assessment
Authors: Wang Frank Fan , Jelinek Clyde , Davis Mary
Published: May 2008

Highly Accelerated Life Test (HALT) uses stimulation to identify weak points in a design thus to improve the quality. When used with proper assessment, HALT is a very useful product development tool. However, HALT without proper assessment is no better than not testing at all. Scientific assessment of the HALT result is critical to successful use of HALT. The following paper will discuss using a physics of failure approach to assessing HALT results. Discussions cover limitations of HALT, comparisons of HALT to traditional testing, and the roles of design specifications and product mechanical characteristics in HALT. Examples of HALT failures and HALT result assessments are also presented.
Development of a Course on Product Design for Environment
Authors: Knight Winston A.
Published: May 2008

This paper outlines the development of a senior undergraduate course concerned with product design for environment. The course sits alongside other well established courses devoted to product design for manufacture and assembly and is aimed at giving students experience of the use of evaluation procedures that enable the environmental impact of products to be taken into account during product design. The course is partially project based and culminates in the students working in small groups to evaluate existing products. Based on this evaluation design changes are developed for improved environmental performance, including ease of recycling.
Nanoscale Modeling and Simulation of Interfacial Bonding of Single-Walled Nanotube Reinforced Composites
Authors: Gou Jihua , Jiang Shunliang , Minaie Bob , Liang Zhiyong , Zhang Chuck , Wang Ben
Published: May 2008

Owning to the extraordinary mechanical, electrical and thermal properties of single-walled nanotubes (SWNTs), SWNT reinforced composites can be used for various applications. In the development of SWNT reinforced composites, one of the fundamental issues that scientists and engineers are confronting is the SWNT-polymer interfacial bonding, which will determine the load transfer capability from the polymer matrix to the nanotube. In single-walled nanotube (SWNT) reinforced epoxy composites, the epoxy resin molecules and the nanotubes are at the nano scale. the interaction at the SWNT/epoxy resin interface is highly dependent on their local molecular structures and bonding. At this small length scale, the lattice structures of the nanotube and the epoxy resin cannot be considered continuous, and their interfacial properties cannot be determined through continuum mechanics. In this paper, the interfacial bonding of SWNT reinforced epoxy composites is investigated using molecular mechanics and molecular dynamics simulations based on a cured epoxy resin model, which is constructed by incorporating three-dimensional crosslinks formed with Shell EPON 862 epoxy resin and EPI CURE W curing agent during polymerization. The interfacial bonding energy between the SWNT and the cured epoxy resin is analyzed using molecular mechanics. Furthermore, the pullout of a SWNT from the cured epoxy resin is investigated using molecular dynamics simulations. Based on the pullout simulation, the interfacial shear strength between the SWNT and the cured epoxy resin is calculated to be up to 75MPa. These analysis results indicate that there could be an effective stress transfer from the epoxy resin to the nanotube.
MEMS-Based Microcalorimeter for Liquid Samples
Authors: Tada Haruna , Wong Peter Y.
Published: May 2008

Advances in MEMS technology has enabled the development of microcalorimeters that have significant improvement in resolution over conventional calorimeters and require smaller samples. However, microcalorimeters have yet to accomplish the variety of tasks that are done by conventional calorimeters, such as study of the thermal properties of polymers and proteins that are typically in liquious state. These applications are especially important in the biomedical field, where combinatorial approaches are used to test a large number of variations in biomaterials. We present a design for a MEMS microcalorimeter that can be applied for a variety of liquid samples. The basic design of the microcalorimeter consists of low stress silicon nitride thin film with nickel resistive heater and thermometer. The heater and thermometer are thermally isolated from each other so that the thermometer accurately measures the temperature of the sample. The silicon nitride film containing the device is suspended over silicon substrate to achieve thermal isolation. Modulation calorimetry technique is used to determine the specific heat of the sample based on the temperature response of the sample when subjected to an AC-modulated heat source. A numerical model was developed to model the thermal behavior of the device. Initial numerical studies found that the device operates optimally at low frequencies, where with appropriate corrections, the device can yield values of heat capacity that are within one percent of the actual value.
Pressure Measurement in Microchannel Using Air Compression
Authors: Lee Sang-Youp , Wereley Steven T.
Published: May 2008

A novel pressure measurement method for use in microchannels has been demonstrated in an experiment designed to measure the entrance length in microchannels. In the prototype device, the small pressure taps with closed ends are located every 100μm along the microchannel with several different lengths and widths. This device measures the local pressure of working fluid from a volume change of trapped air in the pressure taps due to surface tension effect when the microchannel is initially filled with the working liquid. The local pressure of the working liquid is determined by observing the air volume change and then applying the ideal gas law and a constitutive relationship for the water-air interfacial pressure difference due to the surface tension. The experimental and theoretical results show trends which agree well with each other.
Using Senior Lab Projects to Develop Prototypes of Experiments in System Dynamics and Instrumentation
Authors: Layton Richard A.
Published: May 2008

Term projects in a senior-level, non-capstone, mechanical engineering lab course are described in which student teams design, build, and test prototype experiments for future use in sophomore- and junior-level courses in system dynamics and measurement. Project deliverables include the prototype apparatus and courseware such as prelab exercises, lab instructions, and computer programs to be used by the students in the target course. Three such projects are described. The purpose of this paper is to share the concept of using senior-level projects to create prototypes for lower-level courses and to share the conceptual designs of the prototypes for possible duplication and enhancement at other institutions. The projects are partially successful. The apparatuses are viable and the learning objectives of the senior lab course are met but additional work is required before the experiments can be used in the target lower-level courses.
Neural Network Based Perturbation Identification Approach for High Accuracy Tracking Control of Robotic Manipulators
Authors: Moura Jairo , Hosek Martin
Published: May 2008

This paper proposes an approach for high accuracy tracking control of a robotic manipulator in the presence of model perturbations. The proposed approach designs a neural network for estimation and compensation of the modeling errors, also referred to as perturbations. Experiments are carried out on a five-axis direct-drive robotic manipulator for automated pick-place operations in semiconductor manufacturing applications. It is shown that the proposed approach can substantially improve the robot tracking and settling performance of the original computed torque algorithm implemented.
Detecting Plate Damage by Using Wavelets
Authors: Wimmer Stephanie A. , DeGiorgi Virginia G.
Published: May 2008

The detection of damage prior to the degradation of structural parameters of plates is investigated using an algorithm based on the continuous wavelet transform. Plates are examined because they are one of the basic building blocks for many structures, such as naval ships. A representative plate geometry is evaluated using finite element analysis. Damage to connecting joints, stiffeners, cracks, and plate inconsistencies is modeled and the ability of a wavelet based algorithm to detect and locate is evaluated. The plate is subjected to dynamic loads, such as impulse and oscillatory. From the finite element results, time histories are extracted to simulate in-plane strain sensor data. The wavelet algorithm is applied to the strain data.
Air-Assisted Marine Vehicles for Future Use in Transoceanic Transportation
Authors: Matveev Konstantin I.
Published: May 2008

The technical aspects of two types of advanced marine vehicles, Air Cavity Ship and Wing-In-Ground, are considered for future use in transoceanic transportation. Both concepts utilize the air medium to improve technical and economic characteristics of transportation means. The air is supplied under the bottom hull sections of the Air Cavity Ship, reducing the overall wetted surface and consequently hydrodynamic drag. A contact with water is completely eliminated in the case of the Wing-in-Ground, which moves above the water. This results in enhancing the lift-drag ratio in comparison with a flight in the open air. The principles, experience, and research opportunities on the way to make these concepts applicable for transportation are discussed.
Optimal Design and Control of a Rotating Flexible Arm With ACLD Treatment
Authors: Fung E. H. K. , Yau D. T. W.
Published: May 2008

In this paper, the optimal design and control of a rotating clamped-free flexible arm with fully covered active constrained layer damping (ACLD) treatment are studied. The arm is rotating in a horizontal plane in which the gravitational effect and rotary inertia are neglected. The piezo-sensor voltage is fed back to the piezo-actuator via a PD controller. Finite element method (FEM) in conjunction with Hamilton’s principle is used to derive the governing equations of motion of the system which takes into account the effects of centrifugal stiffening due to the rotation of the beam. The damping behavior of the viscoelastic material (VEM) is modeled using the complex shear modulus method. The design optimization objective is to maximize the sum of the first three open-loop modal damping ratios divided by the weight of the damping treatment. A genetic algorithm, differential evolution (DE), combined with a gradient-based algorithm, sequential quadratic programming (SQP), is used to determine the optimal design variables such as the thickness and storage shear modulus of the VEM core. Next for the determined optimal design variables, the optimal control problem is performed to determine the optimal control gains which minimize a quadratic performance index. The control performance index is normalized with respect to the initial conditions and the optimal control problem is posed to solve a min-max optimization problem. The results of this study will be useful in the optimal design and control of adaptive and smart rotating structures such as rotorcraft blades or robotic arms.
The Effective Electromechanical Moduli of Domain Engineered Ferroelectric Crystals
Authors: Li Jiangyu , Liu Dan
Published: May 2008

We present a micromechanical analysis to explain the enhanced electromechanical coupling of domain engineered ferroelectric single crystals. The theory starts with energy-minimization approach, where the energy minimizing domain configurations are characterized as the convex hull of the ferroelectric energy wells, and are constructed by multi-rank laminations. The electromechanical moduli of ferroelectric single crystal with engineered domain configuration can then be determined by the homogenization theory. Using this approach, we analyzed the engineered domain configuration in tetragonal single crystal BaTiO3 poled in <111> direction, where d33 70% higher than those poled in <001> direction has been demonstrated, consistent with experimental observation. It is also found that the two-variant domain configurations have higher enhancement than three-variant systems, suggesting an optimal domain configuration for the enhanced piezoelectric properties. The theory reveals the fundamental property enhancement mechanism in ferroelectric single crystals with engineered domain configuration, and offers insight on the design and optimization of ferroelectric single crystals with superior functional properties.
Computer-Aided Synthesis of Microscale Electrophoretic Separation Systems in Confined Areas
Authors: Pfeiffer Anton J. , Mukherjee Tamal , Hauan Steinar
Published: May 2008

Complex designs result from the desire to create compact microscale electrophoretic devices in confined chip areas. Knowledge of how the interconnectivity of electrophoretic channel sections effects chip performance is necessary to develop feasible and efficient designs. In this paper, we demonstrate an approach for the design and synthesis of microscale electrophoretic systems using computer aided simulation and optimization. We have investigated serpentine and spiral channel topologies which are commonly found in the literature. This approach is demonstrated for the design of systems in confined areas as well as the design of systems that utilize minimal area. Device performance will be evaluated in terms of plate number and resolution and limited by available voltage, detector and fabrication constraints.