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2007

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Articles 5281 - 5310 of 6758

Full-Text Articles in Physical Sciences and Mathematics

Synthesis Of An Anthracyclinone Bearing An Unprecedented Aromatic Ring-Fused Bridgehead-Hydroxylated Bicyclo[3.1.1]Heptanol, Celine Kelso, Jennifer L. Beck, Michael J. Kelso Jan 2007

Synthesis Of An Anthracyclinone Bearing An Unprecedented Aromatic Ring-Fused Bridgehead-Hydroxylated Bicyclo[3.1.1]Heptanol, Celine Kelso, Jennifer L. Beck, Michael J. Kelso

Faculty of Science - Papers (Archive)

This Letter describes the unexpected stereospecific formation of a novel anthracyclinone incorporating the unprecedented aromatic ring-fused bridgehead-hydroxylated bicyclo[3.1.1]heptanol scaffold.


Ground-Based Solar Absorption Ftir Spectroscopy: Characterization Of Retrievals And First Results From A Novel Optical Design Instrument At A New Ndacc Complementary Station, Aldona Waiacek, J R. Taylor, K Strong, R Saari, T Kertzenmacher, Nicholas B. Jones, David W. Griffith Jan 2007

Ground-Based Solar Absorption Ftir Spectroscopy: Characterization Of Retrievals And First Results From A Novel Optical Design Instrument At A New Ndacc Complementary Station, Aldona Waiacek, J R. Taylor, K Strong, R Saari, T Kertzenmacher, Nicholas B. Jones, David W. Griffith

Faculty of Science - Papers (Archive)

The authors describe the optical design of a high-resolution Fourier Transform Spectrometer (FTS), which serves as the primary instrument at the University of Toronto Atmospheric Observatory (TAO). The FTS is dedicated to ground-based infrared solar absorption atmospheric measurements from Toronto, Ontario, Canada. Instrument performance is discussed in terms of instrumental line shape (ILS) and phase error and modulation efficiency as a function of optical path difference. Typical measurement parameters are presented together with retrieval parameters used to derive total and partial column concentrations of ozone. Retrievals at TAO employ the optimal estimation method (OEM), and some impacts of the necessary …


Provincial Paradoxes: 'At Home' With Older Gay Men In A Provincial Town Of The Antipodes, Gordon R. Waitt, Andrew W. Gorman-Murray Jan 2007

Provincial Paradoxes: 'At Home' With Older Gay Men In A Provincial Town Of The Antipodes, Gordon R. Waitt, Andrew W. Gorman-Murray

Faculty of Science - Papers (Archive)

In this paper we explore the importance of ‘home’ in the everyday lives of older gay men living in Townsville, a provincial town in tropical north Queensland. To do this we deploy the work of Alison Blunt and Robin Dowling (2006), who present a spatialised understanding of home. Drawing on interview materials with ten men who identified as gay, and who are also over forty years of age, we demonstrate that home is a crucial site in the production of their subjectivities. We argue that a spatialised understanding of home reveals paradoxical qualities of Townsville-as-home for older gay men. Furthermore, …


Impact Of Data Uncertainty On The Spatio-Temporal Distribution Of Australian Cyclones, 1906-2006, Marjetta L. Puotinen Jan 2007

Impact Of Data Uncertainty On The Spatio-Temporal Distribution Of Australian Cyclones, 1906-2006, Marjetta L. Puotinen

Faculty of Science - Papers (Archive)

Tropical cyclones (known elsewhere as hurricanes or typhoons) regularly track through Australia’s northern coastal regions (Figure 1).

Data documenting the basic characteristics of cyclones in the Australian region is available from the Bureau of Meteorology (BOM) as early as 1906. This data set (freely available in ASCII format at http://www.bom.gov.au) records some 41 attributes (most of which are not complete for the entire time series) for 22,645 individual cyclone eye positions. Because cyclones can cause considerable impact to both marine and terrestrial environments, data sets such as this are widely used to reconstruct past cyclone conditions (for example, see Berz …


Reductive Ring Opening Reactions Of Diphenyldihydrofullerenylpyrroles, William Hawkins, Paul A. Keller, Stephen G. Pyne Jan 2007

Reductive Ring Opening Reactions Of Diphenyldihydrofullerenylpyrroles, William Hawkins, Paul A. Keller, Stephen G. Pyne

Faculty of Science - Papers (Archive)

The reductive ring opening reaction conditions for the simple [60]fullerenyldihydropyrrole 1 have been optimized to include acetic acid in the reaction mixture to rapidly protonate the anionic intermediate. Under these conditions, the ring opened dihydrofullerene 2 was obtained in 68% yield. Under slightly modified conditions and at −78 °C, the reductive bis-ring opening of the tethered trans-4 isomer 3 provided the novel racemic bis-dihydrofullerenyl derivative 7.


Sensor Node Localisation Using A Stereo Camera Rig, Dermot Diamond, Noel E. O'Connor, Alan F. Smeaton, Stephen Beirne, Brian Corcoran, Philip Kelly, King-Tong Lau, Roderick L. Shepherd Jan 2007

Sensor Node Localisation Using A Stereo Camera Rig, Dermot Diamond, Noel E. O'Connor, Alan F. Smeaton, Stephen Beirne, Brian Corcoran, Philip Kelly, King-Tong Lau, Roderick L. Shepherd

Faculty of Science - Papers (Archive)

In this paper, we use stereo vision processing techniques to detect and localise sensors used for monitoring simulated environmental events within an experimental sensor net- work testbed. Our sensor nodes communicate to the camera through patterns emitted by light emitting diodes (LEDs). Ultimately, we envisage the use of very low-cost, low-power, compact microcontroller-based sensing nodes that employ LED communication rather than power hungry RF to trans- mit data that is gathered via existing CCTV infrastructure. To facilitate our research, we have constructed a controlled environment where nodes and cameras can be deployed and potentially hazardous chemical or physical plumes can …


Classification Of Seagrass Habitat Structure As A Reponse To Wave Exposure At Etoile Cay, Seychelles, Sarah Hamylton, Tom Spencer Jan 2007

Classification Of Seagrass Habitat Structure As A Reponse To Wave Exposure At Etoile Cay, Seychelles, Sarah Hamylton, Tom Spencer

Faculty of Science - Papers (Archive)

Physical processes are thought to be a critical control on shallow water communities in the tropics. Past studies of seagrass community patterns have tended to be qualitative and failed to empirically link observed structures with the processes that govern them. Remote sensing technology, in the form of imagery acquired using a Compact Airborne Spectrographic Imager (CASI), has been used to construct a habitat map of seagrass communities at Etoile Cay, Amirantes, Seychelles. . A sim-ple definition of seagrass habitat structure, incorporating measures of complexity and heterogene-ity, has been investigated along a wave exposure gradient via moving window analysis over the …


Forestry For Indigenous Peoples: Learning From Experiences With Forest Industries, Sue Feary Jan 2007

Forestry For Indigenous Peoples: Learning From Experiences With Forest Industries, Sue Feary

Faculty of Science - Papers (Archive)

No abstract provided.


Infrared Spectra Of The Li +_(H 2)N(N=1-3) Cation Complexes, C Emmeluth, B L. J Poad, C D. Thompson, G H. Weddle, E J. Bieske Jan 2007

Infrared Spectra Of The Li +_(H 2)N(N=1-3) Cation Complexes, C Emmeluth, B L. J Poad, C D. Thompson, G H. Weddle, E J. Bieske

Faculty of Science - Papers (Archive)

The Li+–(H2)n n = 1–3 complexes are investigated through infrared spectra recorded in the H–H stretch region (3980–4120 cm−1) and through ab initio calculations at the MP2∕aug-cc-pVQZ level. The rotationally resolved H–H stretch band of Li+–H2 is centered at 4053.4 cm−1 [a −108 cm−1 shift from the Q1(0) transition of H2]. The spectrum exhibits rotational substructure consistent with the complex possessing a T-shaped equilibrium geometry, with the Li+ ion attached to a slightly perturbed H2 molecule. Around 100 rovibrational transitions belonging to …


Interactions Between The Chloride Anion And Aromatic Molecules: Infrared Spectra Of The Cl-_C6h5ch3, Cl-_C6h5nh2 And Cl-_C6h5oh Complexes, Corinna Emmeluth, Berwyck L. J Poad, Christopher D. Thompson, Evan J. Bieske Jan 2007

Interactions Between The Chloride Anion And Aromatic Molecules: Infrared Spectra Of The Cl-_C6h5ch3, Cl-_C6h5nh2 And Cl-_C6h5oh Complexes, Corinna Emmeluth, Berwyck L. J Poad, Christopher D. Thompson, Evan J. Bieske

Faculty of Science - Papers (Archive)

The Cl-−C6H5CH3·Ar, Cl-−C6H5NH2·Ar, and Cl-−C6H5OH·Ar anion complexes are investigated using infrared photodissociation spectroscopy and ab initio calculations at the MP2/aug-cc-pVDZ level. The results indicate that for Cl-−C6H5NH2 and Cl-−C6H5OH, the Cl- anion is attached to the substituent group by a single near-linear hydrogen bond. For Cl-−C6H5CH3, the Cl- is attached to an ortho-hydrogen atom …


Widespread Disruption Of Repressor Element-1 Silencing Transcription Factor/Neuron-Restrictive Silencer Factor Occupancy At Its Target Genes In Huntington's Disease, Chiara Zuccato, Nikolai D. Belyaev, Paola Conforti, Lezanne Ooi, Marzia Tartari, Evangelia Papadimou, Marcy Macdonald, Elisa Fossale, Scott Zeitlin, Noel J. Buckley, Elena Cattaneo Jan 2007

Widespread Disruption Of Repressor Element-1 Silencing Transcription Factor/Neuron-Restrictive Silencer Factor Occupancy At Its Target Genes In Huntington's Disease, Chiara Zuccato, Nikolai D. Belyaev, Paola Conforti, Lezanne Ooi, Marzia Tartari, Evangelia Papadimou, Marcy Macdonald, Elisa Fossale, Scott Zeitlin, Noel J. Buckley, Elena Cattaneo

Faculty of Science - Papers (Archive)

Huntingtin is a protein that is mutated in Huntington's disease (HD), a dominant inherited neurodegenerative disorder. We previously proposed that, in addition to the gained toxic activity of the mutant protein, selective molecular dysfunctions in HD may represent the consequences of the loss of wild-type protein activity. We first reported that wild-type huntingtin positively affects the transcription of the brain-derived neurotrophic factor (BDNF) gene, a cortically derived survival factor for the striatal neurons that are mainly affected in the disease. Mutation in huntingtin decreases BDNF gene transcription. One mechanism involves the activation of repressor element 1/neuron-restrictive silencer element (RE1/NRSE) located …


Vulnerability Of Geomorphological Features In The Great Barrier Reef To Climate Change, Scott Smithers, N Harvey, David Hopley, Colin D. Woodroffe Jan 2007

Vulnerability Of Geomorphological Features In The Great Barrier Reef To Climate Change, Scott Smithers, N Harvey, David Hopley, Colin D. Woodroffe

Faculty of Science - Papers (Archive)

The Great Barrier Reef (GBR) is the largest contiguous coral reef ecosystem in the world81,49. That it is possibly the largest geomorphological structure ever created by living organisms is less widely appreciated. The GBR extends through approximately 15 degrees of latitude and more than 2100 km along the northeast Queensland coast, covering an area of 344,500 km282. It includes more than 2900 reefs of varying types (eg fringing, patch, cresentic, lagoonal, planar), dimensions and stage of growth, which together occupy greater than 20,000 km2, or about 5.8 percent of the total area of the GBR81,82 …


Water Quality In The Illawarra-South Coast Region Of New South Wales, Australia, Robert John Morrison, Mark R. O'Donnell Jan 2007

Water Quality In The Illawarra-South Coast Region Of New South Wales, Australia, Robert John Morrison, Mark R. O'Donnell

Faculty of Science - Papers (Archive)

Water quality is a serious environmental concern in the South Coast region of New South Wales as many aspects of human ecology and the economy are dependant on good water quality. Apart from drinking water for residents and visitors, tourism and agricultural productivity rely on good quality water. This paper presents an overview of general issues with regard to the development of water quality assessment procedures and programs, and discusses a number of issues considered important for the region. These include the impacts of increasing urbanisation, industrial activity (including mining), the potential wider use of groundwater and the improved management …


Intramolecular Versus Intermolecular Oxidative Couplings Of Ester Tethered Di-Aryl Ethers, Stephen R. Taylor, Alison T. Ung, Stephen G. Pyne, Brian W. Skelton, Allan H. White Jan 2007

Intramolecular Versus Intermolecular Oxidative Couplings Of Ester Tethered Di-Aryl Ethers, Stephen R. Taylor, Alison T. Ung, Stephen G. Pyne, Brian W. Skelton, Allan H. White

Faculty of Science - Papers (Archive)

The oxidative cyclization of 3,4-dimethoxyphenyl 3,4-dimethoxyphenylacetate, through intramolecular biphenyl bond formation, was successful and gave the target seven-membered lactone in good yield (85–86%). All other ester substrates gave biphenyl products or their further oxidized products via intermolecular coupling of their radical cation intermediate with the neutral substrate. It appears that matching of the oxidation potentials and nucleophilicity of the two phenyl rings, the positioning of the ring substituents and the ease of E to Z isomerization about the ester C–O bond are important factors contributing to these product outcomes.


'Plus Ca Change ...' Change And Stasis In The Age Of Irish Fertility, 1961-2002: A Spatio-Temporal Analysis, Murray Wilson Jan 2007

'Plus Ca Change ...' Change And Stasis In The Age Of Irish Fertility, 1961-2002: A Spatio-Temporal Analysis, Murray Wilson

Faculty of Science - Papers (Archive)

Since the 1960s Irish fertility has undergone dramatic change. Whilst the broad outlines of both the nature and the origins of such change are, by now, well engough known and understood, little attention has been paid to the way in which changes in age specific fertility have been manifested regionally. This paper uses cluster analysis to group counties and county boroughs/cities according to their age-specific profiles of fertility at each full cencus year between 1961 and 2002 and then ANOVA to identify meaningful statistical relationships between cluster membership in each year and varibles descriptive of the demographic and socio-economic context.


Hybrid Treatment Systems For Dye Wastewater, Faisal I. Hai, Kazuo Yamamoto, Kensuke Fukushi Jan 2007

Hybrid Treatment Systems For Dye Wastewater, Faisal I. Hai, Kazuo Yamamoto, Kensuke Fukushi

Faculty of Science - Papers (Archive)

Virtually all the known physico-chemical and biological techniques have been explored for treatment of extremely recalcitrant dye wastewater; none, however, has emerged as a panacea. A single universally applicable end-of-pipe solution appears to be unrealistic, and combination of appropriate techniques is deemed imperative to devise technically and economically feasible options. An in-depth evaluation of wide range of potential hybrid technologies delineated in literature along with plausible analyses of available cost information has been furnished. In addition to underscoring the indispensability of hybrid technologies, this paper also endorses the inclusion of energy and water reuse plan within the treatment scheme, and …


Late Quaternary Bedrock Incision In The Narmada River At Dardi Falls, Avijit Gupta, Vishwas S. Kale, Lewis A. Owen, A. K. Singhvi Jan 2007

Late Quaternary Bedrock Incision In The Narmada River At Dardi Falls, Avijit Gupta, Vishwas S. Kale, Lewis A. Owen, A. K. Singhvi

Faculty of Science - Papers (Archive)

Fluvial incision in bedrock is common in many rivers of the Indian Peninsula. We investigated a site in the gorge of the Narmada river at Dardi Falls that displays geomorphic evidence of intense bedrock erosion. We report here a terrestrial cosmogenic radionuclide date from an eroded rock surface in Peninsular India. Terrestrial cosmogenic radionuclide dating of the rock surface adjacent to the inner gorge indicated that the minimum age of the gorge is 40 ka. We suggest that the present gorge has developed in two phases, separated by a period of large-scale aggradation that filled the gorge with alluvium. Gorge …


Spatial Models Of Giant Burrowing Frog Distributions, Trent D. Penman, M. Mahony, A. Towerton, Francis Lemckert Jan 2007

Spatial Models Of Giant Burrowing Frog Distributions, Trent D. Penman, M. Mahony, A. Towerton, Francis Lemckert

Faculty of Science - Papers (Archive)

Spatial models of species distributions are becoming a common tool in wildlife management. Most distributional models are developed from point locality data which may limit the modelling process. Habitat variability within a species environment could be included by modelling areas of occurrence rather than point records. This may be particularly important for rare and cryptic species which often have only a small number of known localities. The giant burrowing frog Heleioporus australiacus is a threatened and cryptic species in south-eastern Australia. Previous attempts at modelling its distribution have been largely unsuccessful due to the extremely small number of known localities. …


Stone Axe Technology In Neolithic South India: New Evidence From The Sanganakallu-Kupgal Region, Mideastern Karnataka, A Brumm, Nicole Boivin, Ravi Korisettar, Jinu Koshy, Paula Whittaker Jan 2007

Stone Axe Technology In Neolithic South India: New Evidence From The Sanganakallu-Kupgal Region, Mideastern Karnataka, A Brumm, Nicole Boivin, Ravi Korisettar, Jinu Koshy, Paula Whittaker

Faculty of Science - Papers (Archive)

The transition to agriculture—and to settled village life—occurred at different times in various parts of the world. Even within the Indian subcontinent, the Neolithic transition did not occur simultaneously across the entire region; rather, Neolithic ‘‘pockets’’ developed at di¤erent moments in certain key areas within the subcontinent. One such area is the South Deccan Plateau in South India, where the third millennium b.c. saw the development of a novel Neolithic way of life that di¤ered in crucial ways from Neolithic lifeways in other parts of the subcontinent (Allchin 1963). This tradition was marked by a particular focus on cattle and …


A Task Model Of Software Intensive Acquisitions: An Integrated Tactical Avionics System Case Study, Ricardo Peculis, Derek Rogers, Peter Campbell Jan 2007

A Task Model Of Software Intensive Acquisitions: An Integrated Tactical Avionics System Case Study, Ricardo Peculis, Derek Rogers, Peter Campbell

SMART Infrastructure Facility - Papers

The acquisition of complex software intensive systems is fraught with significant risks and often incurs schedule delays, cost overruns and reduced functionality when the product is finally delivered. This paper presents a model to assess the effectiveness of software intensive acquisitions, founded on the premise that the solution depends on a series of transformations that transform input products in one domain into output products in another domain. Transformations are performed by people, and require knowledge and skills pertinent to both input and output domains. Ideally, products should be transformed without distortions resulting into the desirable solution. In reality, distortions occur …


Embracing Knowledge And Behaviour Management To Improve Performance Of Software Intensive Projects, Ricardo Peculis, Derek Rogers, Peter Campbell Jan 2007

Embracing Knowledge And Behaviour Management To Improve Performance Of Software Intensive Projects, Ricardo Peculis, Derek Rogers, Peter Campbell

SMART Infrastructure Facility - Papers

Many reasons have been offered to explain why software projects fail. Still, software intensive projects often present schedule delays, cost overruns and delivering products with reduced functionality. This paper argues that lack of knowledge is yet another factor that causes projects to under perform, which in turn drives undesirable social behaviour that worsens the situation. Software intensive projects develop solutions highly dependent on software that should satisfy a need. The engineering process to develop such complex solutions comprises of a series of transformations that transform products from one domain into products in another domain, requiring knowledge pertinent to both input …


The Natural Resilience Of Coastal Systems: Primary Concepts, C. D. Woodroffe Jan 2007

The Natural Resilience Of Coastal Systems: Primary Concepts, C. D. Woodroffe

Faculty of Science - Papers (Archive)

Coasts are particularly dynamic and the morphology of the coast is continually changing in response to various processes operating at different rates. Coastal landforms are extremely changeable and coastal habitats change over a range of spatial and temporal scales; recognition of these variations is necessary in order that planning and management can be effective. The increasing realisation that human impacts are affecting our coastlines has promoted the concept of vulnerability. Successful management of coastlines, including mitigation of adverse impacts, must be based on an understanding of natural patterns of change. When a trajectory of change is detected, it is often …


Corticotropin Releasing Hormone - A Gpcr Drug Target, C. Hemley, A. Mccluskey, Paul A. Keller Jan 2007

Corticotropin Releasing Hormone - A Gpcr Drug Target, C. Hemley, A. Mccluskey, Paul A. Keller

Faculty of Science - Papers (Archive)

Corticotrophin Releasing Hormone (CRH) is a primary hormone in the fight or flight response targeting a membrane bound G-protein coupled receptor (GPCR). Many people worldwide stand to benefit by the development of CRH agonists and antagonists for the treatment of anxiety and depression, with additional therapeutic targets including Alzheimer’s, pain and the prevention of premature birth: so why the delay in development? In this review, we will discuss not only CRH, related proteins, receptors and ligands, but some of the obstacles that have arisen, as well as strategies being pursued to overcome these problems in the pursuit of this GPCR …


Cultural Ecology: The Problematic Human And The Terms Of Engagement, Lesley M. Head Jan 2007

Cultural Ecology: The Problematic Human And The Terms Of Engagement, Lesley M. Head

Faculty of Science - Papers (Archive)

As an intellectual container ‘cultural ecology’ is fraught with the same conceptual and ontological problems – what Anderson (2005: 280) calls ‘the stale binaries’ - that attend human impacts, cultural landscapes, indeed human and physical geographies. Yet the rich, detailed and diverse empirical material in evidence at the moment contradicts this in the doing. So perhaps we should be confident that in the public conversations we shall be known best by our works. Our students will be most effective if they can both groundtruth the satellite image of coastal vegetation and explain why the tsunami was experienced very differently by …


Evidence For Historic Coastal High-Energy Wave Impact (Tsunami?) In North Wales, United Kingdom, S. Haslett, Edward A. Bryant Jan 2007

Evidence For Historic Coastal High-Energy Wave Impact (Tsunami?) In North Wales, United Kingdom, S. Haslett, Edward A. Bryant

Faculty of Science - Papers (Archive)

Understanding the contribution of high-energy events (e.g. storms, tsunami) to coastal evolution is currently much debated. Field investigations in North Wales on Anglesey and the Lleyn Peninsula have identified four sites where imbricated boulder trains occur that are discriminators of wave characteristics. Clast analysis indicates that storm wave heights (ca. 20 m), in excess of known extremes (5 to < 9 m), are required to transport them. A plausible explanation is the historic impact of tsunami (≥ 5 m high) that may have been caused either by a) a submarine slide situated offshore on the edge of the continental shelf or Rockall Trough, b) through seismic activity, as the region is one of the most seismically active regions of the British Isles, or c) impact of comet debris in the North Atlantic, with a candidate event around AD 1014. Field evidence suggests that such a high wave-energy event has not recurred along this coast within the last 400 years.


Dnase Sda1 Provides Selection Pressure For A Switch To Invasive Group A Streptococcal Infection, Mark J. Walker, A. Hollands, Martina L. Sanderson-Smith, J. N. Cole, J. K. Kirk, A. Henningham, Jason D. Mcarthur, K. Dinkla, R. K. Aziz, R. G. Kansal, A. J. Simpson, J. T. Buchanan, G. S. Chhatwal, M. Kotb, V. Nizet Jan 2007

Dnase Sda1 Provides Selection Pressure For A Switch To Invasive Group A Streptococcal Infection, Mark J. Walker, A. Hollands, Martina L. Sanderson-Smith, J. N. Cole, J. K. Kirk, A. Henningham, Jason D. Mcarthur, K. Dinkla, R. K. Aziz, R. G. Kansal, A. J. Simpson, J. T. Buchanan, G. S. Chhatwal, M. Kotb, V. Nizet

Faculty of Science - Papers (Archive)

Most invasive bacterial infections are caused by species that more commonly colonize the human host with minimal symptoms. Although phenotypic or genetic correlates underlying a bacterium’s shift to enhanced virulence have been studied, the in vivo selection pressure governing such shifts are poorly understood. The globally disseminated M1T1 clone of group A Streptococcus (GAS) is linked with rare but life-threatening syndromes of necrotizing fasciitis and toxic shock syndrome. Mutations in the GAS control of virulence regulatory sensor kinase (covRS) operon are associated with severe invasive disease, abolishing expression of a broad spectrum cysteine protease (SpeB)2,3 and allowing the recruitment and …


Comparative Analysis Of Resource Reservation Cost For Different Rsvp Extension Schemes In Mobile Environments, Yilin Song, Yi Sun, Min Liu, E. Dutkiewicz Jan 2007

Comparative Analysis Of Resource Reservation Cost For Different Rsvp Extension Schemes In Mobile Environments, Yilin Song, Yi Sun, Min Liu, E. Dutkiewicz

Faculty of Informatics - Papers (Archive)

In wireless networks, advanced resource reservation becomes a necessary requirement for fast handover with QoS guarantee because of the mobility of nodes. However, advanced resource reservation would unavoidably lead to system resource wasting. In this paper, taking the representative RSVP extension schemes with mobility support, MRSVP, Multicast RSVP and Fast RSVP as examples, we analyze factors affecting resource reservation costs and present formalized expressions of reservation costs for these different resource reservation schemes. On this basis, we quantify and compare the reservation costs for different resource reservation schemes, and then give recommendations on resource reservation schemes design for mobile environments.


Re-Conceptualizing The Digital Divide: A Knowledge-Based Approach, William Tibben Jan 2007

Re-Conceptualizing The Digital Divide: A Knowledge-Based Approach, William Tibben

Faculty of Informatics - Papers (Archive)

Determining a robust conceptualization of the digital divide has proved to be a difficult challenge for scholars. This paper argues that a knowledge-based approach provides an effective means to understand and develop responses to various forms of disadvantage related to access and use of Information and Communication Technologies (ICTs). In developing this idea one area of social network analysis is used to make the claim that social networks are used by people to configure an ontology to negotiate the uncertainty of their day-to-day existence. It follows then that digital divide factors can be understood in terms of ICT facilitated knowledge …


Process Discovery From Model And Text Artefacts, Aditya K. Ghose, George Koliadis, Arthur Cheung Jan 2007

Process Discovery From Model And Text Artefacts, Aditya K. Ghose, George Koliadis, Arthur Cheung

Faculty of Informatics - Papers (Archive)

Modeling is an important and time consuming part of the Business Process Management life-cycle. An analyst reviews existing documentation and queries relevant domain experts to construct both mental and concrete models of the domain. To aid this exercise, we propose the Rapid Business Process Discovery (R-BPD) framework and prototype tool that can query heterogeneous information resources (e.g. corporate documentation, web-content, code e.t.c.) and rapidly construct proto-models to be incrementally adjusted to correctness by an analyst. This constitutes a departure from building and constructing models toward just editing them. We believe this rapid mixed-initiative modeling will increase analyst productivity by significant …


Person-Level And Household-Level Regression Estimation In Household Surveys, David G. Steel, Robert Graham Clark Jan 2007

Person-Level And Household-Level Regression Estimation In Household Surveys, David G. Steel, Robert Graham Clark

Faculty of Informatics - Papers (Archive)

A common class of survey designs involves selecting all people within selected households. Generalized regressionestimators can be calculated at either the person or household level. Implementing the estimator at the household level has the convenience of equal estimation weights for people within households. In this article the two approaches are compared theoretically and empirically for the case of simple random sampling of households and selection of all persons in each selected household. We find that the household level approach is theoretically more efficient in large samples and any empirical inefficiency in small samples is limited.