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2006

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Articles 4081 - 4110 of 5872

Full-Text Articles in Physical Sciences and Mathematics

An Application Of Elementary Functions To A Resource Allocation Problem, R. Nillsen Jan 2006

An Application Of Elementary Functions To A Resource Allocation Problem, R. Nillsen

Faculty of Informatics - Papers (Archive)

This paper looks at a problem of resource allocation and analyses the changes and their implications when a particular method of resource allocation is changed, by altering the relative importance of two criteria. The situation considered in the paper arose specifically in the West Report on higher education in Australia (1998), where the possibility of altering the relative importance of research and teaching in allocating university funds in Australia was raised. This possibility was the subject of an article in The Australian newspaper by David Phillips, a former Head of the Higher Education Division in the Department of Employment, Education, …

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An Application Of Quadratic Functions To Australian Government Policy On Funding Schools, R. Nillsen Jan 2006

An Application Of Quadratic Functions To Australian Government Policy On Funding Schools, R. Nillsen

Faculty of Informatics - Papers (Archive)

In the Sydney Morning Herald newspaper of 23rd March 2005 the economics writer Ross Gittins argued that the funding arrangements for private schools in Australia positively encourage parents to move their children from the state system to the private system. The Federal minister, Dr Brendan Nelson, responded by saying that the policy of subsidising pupils who go to a private school results in taxpayer savings of $4 billion. However, the minister's response did not address the extent to which more funds could possibly be saved by having a different subsidy from the one currently offered by the government. Now, there …

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A Closed-Form Analytical Solution For The Valuation Of Convertible Bonds With Constant Dividend Yield, Song-Ping Zhu Jan 2006

A Closed-Form Analytical Solution For The Valuation Of Convertible Bonds With Constant Dividend Yield, Song-Ping Zhu

Faculty of Informatics - Papers (Archive)

In this paper, a closed-form analytical solution for pricing convertible bonds on a single underlying asset with constant dividend yield is presented. To the au- thor’s best knowledge, never has a closed-form analytical formula been found for American-style convertible bonds (CBs) of finite maturity time although there have been quite a few approximate solutions and numerical approaches proposed. The solution presented here is written in the form of a Taylor’s series expansion, which 1 contains infinitely many terms, and thus is completely analytical and in a closed form. Although it is only for simplest CBs without call or put features, …

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Pricing Convertible Bonds Based On A Multi-Stage Compound Option Model, P. Gong, Z. He, Song-Ping Zhu Jan 2006

Pricing Convertible Bonds Based On A Multi-Stage Compound Option Model, P. Gong, Z. He, Song-Ping Zhu

Faculty of Informatics - Papers (Archive)

In this paper, we introduce the concept of multi-stage compound options to the valuation of convertible bonds. Rather than evaluating a nested high-dimensional integral that has arisen from the valuation of multi-stage compound options, we found that adopting the Finite Difference Method (FDM) to solve the Black-Scholes equation for each stage actually resulted in a better numerical efficiency. By comparing our results with those obtained by solving the Black-Scholes equation directly, we can show that the new approach does provide an approximation approach for the valuation of convertible bonds and demonstrate that it offers a great potential for a further …

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Mobility Management For Untethered Immersive Communications, Mehran Dowlatshahi, Farzad Safaei Jan 2006

Mobility Management For Untethered Immersive Communications, Mehran Dowlatshahi, Farzad Safaei

Faculty of Informatics - Papers (Archive)

In this paper we propose a system design for delivery of immersive communications to mobile wireless devices based on a distributed proxy model. It is demonstrated that this architecture addresses key technical challenges for the delivery of these services, that is, constraints on link capacity and power consumption in mobile devices. However, additional complexity is introduced with respect to mobility management. The paper proposes three possible methods for updating proxy assignments in response to mobility and compares the performance of these methods.

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Multipoint Interactive Communication For Peer To Peer Environments, Mehran Dowlatshahi, Farzad Safaei Jan 2006

Multipoint Interactive Communication For Peer To Peer Environments, Mehran Dowlatshahi, Farzad Safaei

Faculty of Informatics - Papers (Archive)

In this paper a scheme for peer-to-peer (p2p) multiparty voice communication is proposed. The paper considers realistic constraints on the upstream and downstream bandwidth of peers and their processing capacity. We propose a novel mechanism for distributed mixing of the audio streams that can improve the scalability of this service while meeting the capacity constraints. The paper also proposes an algorithm to form a multipoint-to-multipoint spanning tree (MMST) among the peers within a communication zone. The simulation results show that the performance of algorithm in terms of delay stretch and its impact on bandwidth reduction in comparison to multiple source …

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Image Content Annotation Based On Visual Features, Lei Ye, Philip Ogunbona, J. Wang Jan 2006

Image Content Annotation Based On Visual Features, Lei Ye, Philip Ogunbona, J. Wang

Faculty of Informatics - Papers (Archive)

Automatic image content annotation techniques attempt to explore structural visual features of images that describe image content and associate them with image semantics. In this paper, two types of concept spaces, atomic concept and collective concept spaces, are defined and the annotation problems in those spaces are formulated as feature classification and Bayesian inference, respectively. A scheme of image content annotation in this framework is presented and evaluated as an application of photo categorization using MPEG-7 VCE2 dataset and its ground truth. The experimental results show a promising performance.

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Managing Latency And Fairness In Networked Games, J. Brun, Farzad Safaei, P. Boustead Jan 2006

Managing Latency And Fairness In Networked Games, J. Brun, Farzad Safaei, P. Boustead

Faculty of Informatics - Papers (Archive)

Networked games can be seen as forerunners of all kinds of participatory entertainment applications delivered through the Internet. Physically dispersed players are immersed in a common virtual environment where they interact in real time. When a user performs an action, other users must be made aware of that action. Otherwise, there is a discrepancy in the perceptions of participants about the overall state of the virtual world. This discrepancy could lead to undesirable and sometimes paradoxical outcomes. In particular, first-person shooter, and to a lesser extent role-playing games impose stringent constraints on responsiveness and consistency.

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New Constructing Of Regular Hadamard Matrices, Tianbing Xia, Jennifer Seberry, M. Xia Jan 2006

New Constructing Of Regular Hadamard Matrices, Tianbing Xia, Jennifer Seberry, M. Xia

Faculty of Informatics - Papers (Archive)

For every prime power q ≡ 7 mod 16, we obtain the (q; a, b, c, d)–partitions of G F (q), with odd integers a, b, c, d, a ≡ ± 1 mod 8 such that q = a2 + 2(b2 + c2 + d2) and d2 = b2 + 2ac + 2bd. Hence for each value of q the construction of SDS becomes equivalent to building a (q; a, b, c, d)–partition. The latter is much easier than the former. We give …

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Electronic Versus Paper-Based Nursing Documentation Systems: The Caregivers Weigh In, Ping Yu Jan 2006

Electronic Versus Paper-Based Nursing Documentation Systems: The Caregivers Weigh In, Ping Yu

Faculty of Informatics - Papers (Archive)

Information technology (IT) solutions have the potential to free carers in long-term care facilities from well-known problems with burdensome paper-documentation, allow them more direct care-time with clients and improve the quality of nursing records. However, to date, little scientific evidence is available to support this idea. Besides the concern about return on investment, a big barrier for the slow uptake of IT solutions in long-term care1 is scepticism by managers about the capacity and willingness of older carers, most of them women, to use computers and the uncertainty about the potential change associated with introducing a new system. To my …

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Accounting For The Uncertainty Of Information On Clustering In The Design Of A Clustered Sample, David G. Steel, Robert Graham Clark Jan 2006

Accounting For The Uncertainty Of Information On Clustering In The Design Of A Clustered Sample, David G. Steel, Robert Graham Clark

Faculty of Informatics - Papers (Archive)

An important decision that has to be made in developing the design of a cluster or multi-stage sampling scheme is the number of units to select at each stage of selection. For a two-stage design we need to decide the number of units to select from each Primary Sampling Unit (PSU) in the sample. A common approach is to estimate the costs and the variance components associated with each stage of selection and determine an optimal design. This is usually done for estimates of the means or totals of one or a small number of variables. In practice the measure …

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Thermionic Cooling In Cylindrical Semiconductor Nanostructures, Pin Lyu, Chao Zhang Jan 2006

Thermionic Cooling In Cylindrical Semiconductor Nanostructures, Pin Lyu, Chao Zhang

Australian Institute for Innovative Materials - Papers

The authors analyzed the thermionic cooling efficiency of the cylindrical semiconductor nanostructures. It is shown that due to the reduced emission current from the inner electrode, the cooling efficiency can be enhanced if the outer cylinder is the cold electrode. The threshold voltage for thermionic cooling is lower in cylindrical devices as compared to that in planar devices. The competition between the heat transport by electrons and the heat conduction by phonons is responsible for the efficiency enhancement and the voltage reduction.

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Magnetic And Transport Properties Of Transition Metal Doped Polycrystalline In2o3, Germanas Peleckis, Xiaolin Wang, S X. Dou Jan 2006

Magnetic And Transport Properties Of Transition Metal Doped Polycrystalline In2o3, Germanas Peleckis, Xiaolin Wang, S X. Dou

Australian Institute for Innovative Materials - Papers

Synthesis and characterization of transition metal (TM)-doped In 2O3 oxide is reported. Most of the samples were found to be paramagnetic, and only Ye and Cr co-doped sample showed as light trace of ferromagnetism at 300 K with saturation magnetization M s = 0.35 emug/g. Measured transport properties revealed significant differences in transport among the samples. The absolute value of electrical resistivity for the In1.8Fe0.1Mn0.1O3 sample at 300 K was rho= 9.4 x 103 Omega middot cm, while In1.8Fe0.1Cr0.1O3 had rho = 62 …

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Formation Of Magnesium Diboride-Based Materials With High Critical Currents And Mechanical Characteristics By High-Pressure Synthesis, Tetiana Prikhna, W. Gawalek, Ya M. Savchuk, N. V. Sergienko, V. E. Moshchil, M. Wendt, M. Zeisberger, T. Habisreuther, V. B. Sverdun, S X. Dou, S. N. Dub, V. S. Melnikov, Ch Schmidt, J. Dellith, P. A. Nagorny Jan 2006

Formation Of Magnesium Diboride-Based Materials With High Critical Currents And Mechanical Characteristics By High-Pressure Synthesis, Tetiana Prikhna, W. Gawalek, Ya M. Savchuk, N. V. Sergienko, V. E. Moshchil, M. Wendt, M. Zeisberger, T. Habisreuther, V. B. Sverdun, S X. Dou, S. N. Dub, V. S. Melnikov, Ch Schmidt, J. Dellith, P. A. Nagorny

Australian Institute for Innovative Materials - Papers

The developed method of high-pressure synthesis (HPS) allows producing nanostructural highly dense material based on MGB2, which possesses the highest superconducting and mechanical characteristics among the known world analogues, in the form of blocks that are suitable for application in SC electromotors and pumps. Additions of Zr can increase critical current density (jc) of synthesized at 2 GPa and 750-800 °C MGB2 in the same manner as additions of Ta or Ti, i.e. due to the absorption of impurity hydrogen forming the ZrH2. The formation of ZrB2 phase at higher synthesis …

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Carbohydrate Doping To Enhance Electromagnetic Properties Of Mgb2 Superconductors, Jung Ho Kim, Sihai Zhou, Md S. Hossain, Alexey V. Pan, S X. Dou Jan 2006

Carbohydrate Doping To Enhance Electromagnetic Properties Of Mgb2 Superconductors, Jung Ho Kim, Sihai Zhou, Md S. Hossain, Alexey V. Pan, S X. Dou

Australian Institute for Innovative Materials - Papers

The effect of carbohydrate doping on lattice parameters, microstructure, Tc, Jc, Hirr, and Hc2 of MgB2 has been studied. In this work the authors used malic acid as an example of carbohydrates as an additive to MgB2. The advantages of carbohydrate doping include homogeneous mixing of precursor powders, avoidance of expansive nanoadditives, production of highly reactive C, and significant enhancement in Jc, Hirr, and Hc2 of MgB2, compared to undoped samples. The Jc for MgB2+30 wt% C4H6 …

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A Flip-Disorder In The Structure Of 3-[2-(Anthracen-9-Yl)Ethenyl]Thiophene, Pawel Wagner, David L. Officer, Maciej Kubicki Jan 2006

A Flip-Disorder In The Structure Of 3-[2-(Anthracen-9-Yl)Ethenyl]Thiophene, Pawel Wagner, David L. Officer, Maciej Kubicki

Australian Institute for Innovative Materials - Papers

In the crystal structure of the title compound, C20H14S, the thio­phene rings are disordered; such a flip-type disorder is typical for simple, monosubstituted thio­phene derivatives. Two planar fragments, the thio­phene and the anthracene units, are almost perpendicular in order to relieve the H⋯H steric strains. The crystal packing is determined by van der Waals inter­actions, π–π stacking between the anthracene fragments, and some weak C—H⋯S and C—H⋯π short directional contacts.

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2,5-Bis(2-Cyano-2-Thienylvinyl)Thiophene, Pawel Wagner, David L. Officer, Maciej Kubicki Jan 2006

2,5-Bis(2-Cyano-2-Thienylvinyl)Thiophene, Pawel Wagner, David L. Officer, Maciej Kubicki

Australian Institute for Innovative Materials - Papers

In the crystal structure of the title compound, C18H10N2S3, the terminal thio­phene rings are disordered. This disorder is of a flip-type and has been observed in some other thio­phene derivatives. The mol­ecule as a whole is approximately planar; the dihedral angle between the terminal five-membered rings is 6.0 (2)°. The crystal packing is determined by van der Waals inter­actions, π–π stair-like stacking between the thio­phene rings, and some weak C—H⋯S and C—H⋯π short directional contacts.

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Electrochemical Study Of 1,3-Indandione Derivatives Of Terthiophenes, Mieczyslaw Lapkowski, Sylwia Plewa, Pawel Wagner, David L. Officer Jan 2006

Electrochemical Study Of 1,3-Indandione Derivatives Of Terthiophenes, Mieczyslaw Lapkowski, Sylwia Plewa, Pawel Wagner, David L. Officer

Australian Institute for Innovative Materials - Papers

Properties and behavior of a group of four newly synthesized derivatives of terthiophene and terthienylenvinylene was studied. All four investigated monomers bear a 1,3-indandione substituent at the central thiophene ring and two of them (ThIV, ThIVM) have additional vinyl bonds introduced between the thiophene rings. In addition, ThIM and ThIVM have 5 positions of the two terminal rings blocked with methyl groups. The measurements were done using cyclic voltamperometry (CV) in solutions of 0.1M Bu4NBF4 in CH2Cl2. It was found that ThI and ThIV polymerise easily. CV of ThI reveals a reduction peak …

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Low-Cost Surface-Mount Led Gas Sensor, Roderick Shepherd, William S. Yerazunis, King Tong Lau, Dermot Diamond Jan 2006

Low-Cost Surface-Mount Led Gas Sensor, Roderick Shepherd, William S. Yerazunis, King Tong Lau, Dermot Diamond

Australian Institute for Innovative Materials - Papers

A low-cost chemical sensor comprising surface-mount light-emitting diodes (LEDs) has been developed for colorimetric gas detection. The device consists of a pair of LEDs connected to a simple PIC microcontroller circuit and in the most basic form, requires the use of only two input-output (I/O) pins on the chip. The key features of this sensor are the use of a LED rather than a photodiode for light detection and an all-digital light detection protocol that leads to a reduction in cost and power consumption by avoiding the need for an analog-to-digital converter. The surface-mount diodes employed are more compact than …

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Sampling Patchily Distributed Taxa: A Case Study Using Cost-Benefit Analyses For Sponges And Ascidians In Coastal Lakes Of New South Wales, Australia, P. B. Barnes, A. R. Davis, D. E. Roberts Jan 2006

Sampling Patchily Distributed Taxa: A Case Study Using Cost-Benefit Analyses For Sponges And Ascidians In Coastal Lakes Of New South Wales, Australia, P. B. Barnes, A. R. Davis, D. E. Roberts

Faculty of Science - Papers (Archive)

Estuaries worldwide are under increasing threat from human impacts. Because much of their fauna remains unstudied and in many cases undescribed, these systems present real challenges for effective management. In eastern Australia the study of estuarine fauna is often further complicated by its patchy distributions. This is particularly the case for assemblages of sessile invertebrates in coastal saline lakes. This study quantified distributions of sponges and ascidians at a hierarchy of spatial scales in the seagrass meadows of 2 coastal saline lakes in New South Wales, Australia. Nine species of sponge, many of which were undescribed, and 3 species of …

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Targeting C-Reactive Protein For The Treatment Of Cardiovascular Disease, Mark B. Pepys, Gideon M. Hirschfield, Glenys A. Tennent, J Ruth Gallimore, Melvyn C. Kahan, Vittorio Bellotti, Philip N. Hawkins, Rebecca M. Myers, Martin D. Smith, Alessandra Polara, Alexander J. A Cobb, Steven V. Ley, J. Andrew Aquilina, Carol V. Robinson, Isam Sharif, Gillian A. Gray, Caroline A. Sabin, Michelle C. Jenvey, Simon E. Kolstoe, Darren Thompson, Stephen P. Wood Jan 2006

Targeting C-Reactive Protein For The Treatment Of Cardiovascular Disease, Mark B. Pepys, Gideon M. Hirschfield, Glenys A. Tennent, J Ruth Gallimore, Melvyn C. Kahan, Vittorio Bellotti, Philip N. Hawkins, Rebecca M. Myers, Martin D. Smith, Alessandra Polara, Alexander J. A Cobb, Steven V. Ley, J. Andrew Aquilina, Carol V. Robinson, Isam Sharif, Gillian A. Gray, Caroline A. Sabin, Michelle C. Jenvey, Simon E. Kolstoe, Darren Thompson, Stephen P. Wood

Faculty of Science - Papers (Archive)

Complement-mediated inflammation exacerbates the tissue injury of ischaemic necrosis in heart attacks and strokes, the most common causes of death in developed countries. Large infarct size increases immediate morbidity and mortality and, in survivors of the acute event, larger non-functional scars adversely affect long-term prognosis. There is thus an important unmet medical need for new cardioprotective and neuroprotective treatments. We have previously shown that human C-reactive protein (CRP), the classical acute-phase protein that binds to ligands exposed in damaged tissue and then activates complement1, increases myocardial and cerebral infarct size in rats subjected to coronary or cerebral artery ligation, respectively2,3. …

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Microwave-Assisted Facile Synthesis And Crystal Structure Of Cis-9,10,11,15-Tetrahydro-9,10[3'4']-Furanoanthracene-12,14-Dione, Weerachai Phutdhawong, Duang Buddhasukh, Stephen G. Pyne, Apinpus Rujiwatra, Chaveng Pakawatchai Jan 2006

Microwave-Assisted Facile Synthesis And Crystal Structure Of Cis-9,10,11,15-Tetrahydro-9,10[3'4']-Furanoanthracene-12,14-Dione, Weerachai Phutdhawong, Duang Buddhasukh, Stephen G. Pyne, Apinpus Rujiwatra, Chaveng Pakawatchai

Faculty of Science - Papers (Archive)

A facile synthesis and crystal structure of cis‐9,10,11,15‐tetrahydro‐9,10[3′,4′]‐furanoanthracene‐12,14‐dione from the reaction of anthracene and maleic anhydride in xylene in a short time and high yield using a modified commercial domestic microwave oven is reported.

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Comparisons Between Sciamachy And Ground-Based Ftir Data For Total Columns Of Co, Ch4, Co2 And N2o, B Dils, M De Maziere, J F. Muller, T Blumenstock, Nicholas B. Jones, David W. Griffith, C P Rinsland, E Mahieu, S Wood, R De Beek, P Demoulin, M Buchwitz, P Duchatelet, C Frankenberg, A Gloudemans, T Kerzenmacher, I Kramer, J Mellqvist, H Shrijver, A Strandberg, D Smale, W Stremme, A G. Straume, R Sussmann, M Van Den Broek, T Wagner, K Strong, Aldona Wiacek, J R. Taylor, Hans Fast, Thorsten Warneke, Richard L. Mittermeier, Justus Notholt, Voltaire A. Velazco Jan 2006

Comparisons Between Sciamachy And Ground-Based Ftir Data For Total Columns Of Co, Ch4, Co2 And N2o, B Dils, M De Maziere, J F. Muller, T Blumenstock, Nicholas B. Jones, David W. Griffith, C P Rinsland, E Mahieu, S Wood, R De Beek, P Demoulin, M Buchwitz, P Duchatelet, C Frankenberg, A Gloudemans, T Kerzenmacher, I Kramer, J Mellqvist, H Shrijver, A Strandberg, D Smale, W Stremme, A G. Straume, R Sussmann, M Van Den Broek, T Wagner, K Strong, Aldona Wiacek, J R. Taylor, Hans Fast, Thorsten Warneke, Richard L. Mittermeier, Justus Notholt, Voltaire A. Velazco

Faculty of Science - Papers (Archive)

Total column amounts of CO, CH4, CO2 and N2O retrieved from SCIAMACHY nadir observations in its near-infrared channels have been compared to data from a ground-based quasi-global network of Fourier-transform infrared (FTIR) spectrometers. The SCIAMACHY data considered here have been produced by three different retrieval algorithms, WFM-DOAS (version 0.5 for CO and CH4 and version 0.4 for CO2 and N2O), IMAP-DOAS (version 1.1 and 0.9 (for CO)) and IMLM (version 6.3) and cover the January to December 2003 time period. Comparisons have been made for individual data, as well as for monthly averages. To maximize the number of reliable coincidences …

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Rotationally Resolved Infrared Spectrum Of The Li+_D2 Cation Complex, C D. Thompson, C Emmeluth, B L. J Poad, G H. Weddle, E J. Bieske Jan 2006

Rotationally Resolved Infrared Spectrum Of The Li+_D2 Cation Complex, C D. Thompson, C Emmeluth, B L. J Poad, G H. Weddle, E J. Bieske

Faculty of Science - Papers (Archive)

The infrared spectrum of mass selected Li +-D 2 cations is recorded in the D-D stretch region (2860-2950 cm -1) in a tandem mass spectrometer by monitoring Li + photofragments. The D-D stretch vibration of Li +-D 2 is shifted by -79 cm -1 from that of the free D 2 molecule indicating that the vibrational excitation of the D 2 subunit strengthens the effective Li +-D 2 intermolecular interaction. Around 100 rovibrational transitions, belonging to parallel K a=0-0, 1-1, and 2-2 subbands, are fitted to a Watson A-reduced Hamiltonian to yield effective molecular parameters. The infrared spectrum shows that …

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'Good Engineering Governance' - An Issue For Ergonomists, J V. Nendick, M Hassan, E N. Urwin, Grace A. Kennedy, C E. Siemieniuch, M A. Sinclair Jan 2006

'Good Engineering Governance' - An Issue For Ergonomists, J V. Nendick, M Hassan, E N. Urwin, Grace A. Kennedy, C E. Siemieniuch, M A. Sinclair

SMART Infrastructure Facility - Papers

Engineering Governance can be summarised as two questions: 'Are we doing the right things?' and 'Are we doing those things right?'. It forms a part of Corporate Governance, and in the manufacturing domain it is the key to long-term survival amid changing commercial contexts. The paper will outline some of the ergonomics issues of importance in this topic; 'ownership' of goverrnance; implications for design, production and operation; and, perhaps most important for Ergonomists, the resulting implications for the design of jobs. These implications cover organisational discipline, the inclusion of suitable, 'effort-free' metrics in engineering processes, the allocation of responsibility and …

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Trapping Of A Tert-Adamantyl Peroxyl Radical In The Gas Phase, D. G. Harman, Stephen J. Blanksby Jan 2006

Trapping Of A Tert-Adamantyl Peroxyl Radical In The Gas Phase, D. G. Harman, Stephen J. Blanksby

Faculty of Science - Papers (Archive)

A bridgehead adamantyl peroxyl radical has been prepared and isolated in the gas phase by the reaction of a distonic radical anion with dioxygen in a quadrupole ion-trap mass spectrometer.

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Development Of Robust Guidelines And Assessment Procedures For Metal Contaminated Sediments, David Strom, Stuart L. Simpson, Dianne F. Jolley Jan 2006

Development Of Robust Guidelines And Assessment Procedures For Metal Contaminated Sediments, David Strom, Stuart L. Simpson, Dianne F. Jolley

Faculty of Science - Papers (Archive)

Assessment of contaminated sediments and development of remediation strategies is becoming an important priority for regulators and industries worldwide. Although sediment quality assessment frameworks exist, poor scientific procedures and a limited understanding of species sensitivity to common contaminants hinders most assessment programs. Globally, sediment quality guidelines (SQGs) for metals vary over several orders of magnitude and are not based on clear cause-effect relationships. Although equilibrium partitioning approaches to developing SQGs have been attempted, the cause-effect relationships are weak due to the many other modifying factors that influence metal bioavailability and toxicity. The inherent lack of defensible SQGs for metals currently …

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Are Seed Dispersal And Predation In Fire-Sensitive Persoonia Species (Proteacae) Associated With Rarity?, Paul Rymer Jan 2006

Are Seed Dispersal And Predation In Fire-Sensitive Persoonia Species (Proteacae) Associated With Rarity?, Paul Rymer

Faculty of Science - Papers (Archive)

Seed dispersal and predation are key processes affecting the colonization and extinction of populations in fire-prone environments. If these processes influence distribution and abundance, rare species may be expected to have less seed removal and/or greater seed predation than common congeners. I compared seed removal and predation under plants in two closely related pairs of fire-sensitive common and rare Persoonia species with fleshy fruits in two replicate populations of each species. Seed removal by macropods was significantly greater in the two common species (>50% seeds/plant) than in their rare congeners (<25%). There was no overall effect of rarity on seed predation by rodents, but there were significantly more seeds of the rare Persoonia mollis subspecies maxima eaten than of the other three species. Plant size was the only attribute measured that was significantly correlated with seed removal (r ¼ 0:50). After including plant size as a covariate in the analysis, I still detected a significant effect of rarity on seed removal. High levels of seed removal were sustained in both small and large populations of the common Persoonia lanceolata, suggesting that population size may not be contributing to the differences between these common and rare species. The common-rare difference in the seed removal of Persoonia species seems robust across several plant and population attributes.

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The Sydney Basin And Frozen Prawns - The Cool Mineral Connection, Paul Carr, Brian G. Jones, Bruce Selleck Jan 2006

The Sydney Basin And Frozen Prawns - The Cool Mineral Connection, Paul Carr, Brian G. Jones, Bruce Selleck

Faculty of Science - Papers (Archive)

Calcite pseudomorphs after ikaite (glendonite) are common in the Permian marine sequences of the Sydney Basin and have been recorded from more than 30 localities representing six major glenonite-forming intervals. Recognition of glenonites in Sydney Basin strata provides unequivocal evidence for coldwater deposition.

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Aquariums As Reservoirs For Multidrug-Resistant Salmonella Paratyphi B, Renee Levings, D. Lightfoot, R. M. Hall, Steven P. Djordjevic Jan 2006

Aquariums As Reservoirs For Multidrug-Resistant Salmonella Paratyphi B, Renee Levings, D. Lightfoot, R. M. Hall, Steven P. Djordjevic

Faculty of Science - Papers (Archive)

Multidrug-resistant Salmonella enterica serovar Paratyphi B dT+ isolates from patients with gastroenteritis were identical with isolates from their home aquariums. Matched isolates had identical phage types, XbaI and IS200 profiles, and Salmonella genomic island 1 (SGI1). Ornamental fish tanks are reservoirs for SGI1-containing S. Paratyphi B dT+.

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