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31.
John Strassner Sven van der Meer Declan O’Sullivan Simon Dobson 《Journal of Network and Systems Management》2009,17(3):255-284
The purpose of autonomic networking is to manage the business and technical complexity of networked components and systems.
However, existing network management data has no link to business concepts. This makes it very difficult to ensure that services
offered by the network are meeting business objectives. This paper describes a novel context-aware policy model that uses
a combination of modeled and ontological data to determine the current context, which policies are applicable to that context,
and what services and resources should be offered to which users and applications.
John Strassner is the director of autonomic research in the Telecommunications Systems & Software Group in Waterford Institute of Technology, and a Visiting Professor at POSTECH. His research interests are in autonomic systems, policy based management, machine learning, and semantic reasoning. He is the Chairman of the Autonomic Communications Forum, and the past chair of the TMF’s NGOSS SID, metamodel and policy working groups. He has authored two books, written chapters for five other books, and co-edited five journals on network and service management and autonomics. John is the recipient of the Daniel A. Stokesbury memorial award for excellence in network management, and has authored 211 refereed journal papers and publications. Sven van der Meer received his M.Sc in computer science and his Dr.-Ing. from Technical University Berlin (TUB), Germany, in 1996 and 2002. Since November 2002, Sven has been a research fellow at the Telecommunications Software & Systems Group at the Waterford Institute of Technology. Since October 2004 he is Senior Investigator of the Competence Centre for Communication Infrastructure Management at TSSG, involved in the Architecture and Information Modelling teams in the TMF, and has served as editor for Technological Neutral Architecture and Contracts specifications within the TM Forum. Declan O’Sullivan is the director of the Knowledge and Data Engineering (KDEG) research group in Trinity College Dublin (TCD). His research interests are in the use of semantic-driven approaches for network and service management, in particular to enable semantic interoperability. He is currently a Principal Investigator in the SFI funded research project investigating Federated Autonomic Management Environments (FAME). O’Sullivan has a Ph.D. and a M.Sc in computer science from TCD. Simon Dobson is a co-founder of the Systems Research Group at UCD Dublin. His research centers around adaptive pervasive computing and novel programming techniques. He is on the editorial boards of the Journal of Network and Systems Management and the International Journal of Autonomous and Adaptive Communications Systems, and participates in a number of EU strategic workshops and working groups. He is National Director and vice-president of the European Research Consortium for Informatics and Mathematics, a board member of the Autonomic Communication Forum, and a member of the IBEC/ICT Ireland standing committee on academic/industrial research and development. He holds a BSc and DPhil in computer science, is a Chartered Fellow of the British Computer Society, a Chartered Engineer, and member of the IEEE and ACM. 相似文献
Simon DobsonEmail: |
John Strassner is the director of autonomic research in the Telecommunications Systems & Software Group in Waterford Institute of Technology, and a Visiting Professor at POSTECH. His research interests are in autonomic systems, policy based management, machine learning, and semantic reasoning. He is the Chairman of the Autonomic Communications Forum, and the past chair of the TMF’s NGOSS SID, metamodel and policy working groups. He has authored two books, written chapters for five other books, and co-edited five journals on network and service management and autonomics. John is the recipient of the Daniel A. Stokesbury memorial award for excellence in network management, and has authored 211 refereed journal papers and publications. Sven van der Meer received his M.Sc in computer science and his Dr.-Ing. from Technical University Berlin (TUB), Germany, in 1996 and 2002. Since November 2002, Sven has been a research fellow at the Telecommunications Software & Systems Group at the Waterford Institute of Technology. Since October 2004 he is Senior Investigator of the Competence Centre for Communication Infrastructure Management at TSSG, involved in the Architecture and Information Modelling teams in the TMF, and has served as editor for Technological Neutral Architecture and Contracts specifications within the TM Forum. Declan O’Sullivan is the director of the Knowledge and Data Engineering (KDEG) research group in Trinity College Dublin (TCD). His research interests are in the use of semantic-driven approaches for network and service management, in particular to enable semantic interoperability. He is currently a Principal Investigator in the SFI funded research project investigating Federated Autonomic Management Environments (FAME). O’Sullivan has a Ph.D. and a M.Sc in computer science from TCD. Simon Dobson is a co-founder of the Systems Research Group at UCD Dublin. His research centers around adaptive pervasive computing and novel programming techniques. He is on the editorial boards of the Journal of Network and Systems Management and the International Journal of Autonomous and Adaptive Communications Systems, and participates in a number of EU strategic workshops and working groups. He is National Director and vice-president of the European Research Consortium for Informatics and Mathematics, a board member of the Autonomic Communication Forum, and a member of the IBEC/ICT Ireland standing committee on academic/industrial research and development. He holds a BSc and DPhil in computer science, is a Chartered Fellow of the British Computer Society, a Chartered Engineer, and member of the IEEE and ACM. 相似文献
32.
Liu Zhicheng Stasko John Sullivan Timothy 《IEEE transactions on visualization and computer graphics》2009,15(6):1025-1032
We present a case study of our experience designing SellTrend, a visualization system for analyzing airline travel purchase requests. The relevant transaction data can be characterized as multi-variate temporal and categorical event sequences, and the chief problem addressed is how to help company analysts identify complex combinations of transaction attributes that contribute to failed purchase requests. SellTrend combines a diverse set of techniques ranging from time series visualization to faceted browsing and historical trend analysis in order to help analysts make sense of the data. We believe that the combination of views and interaction capabilities in SellTrend provides an innovative approach to this problem and to other similar types of multivariate, temporally driven transaction data analysis. Initial feedback from company analysts confirms the utility and benefits of the system. 相似文献
33.
The successful fabrication of metal/dielectric multilayer filters requires not only accurate control of the individual layer thicknesses, but also a good knowledge of the optical constants of the materials used in the filters. In the case of metal films, it is also essential to know whether any transition layers are formed at the interfaces and, if so, how their thicknesses and optical constants depend on the deposition conditions. An automatic, real-time process control, magnetron sputtering deposition system was modified to permit the manufacture of metal/dielectric filters using optical monitoring techniques. To illustrate the performance of this system, two bandpass filters, a short-wavelength pass filter, and a neutral density filter were produced, all having a low reflectance for light incident on one side. The metal layers used in these filters consisted of either Ni or Ag. TheAg films could be protected from the O(2) plasma using thin Ni or Si films. Good agreement was obtained between the calculated and measured spectral transmittance and reflectance curves. 相似文献
34.
Paulsen KD Meaney PM Moskowitz MJ Sullivan JR 《IEEE transactions on medical imaging》1995,14(3):504-514
The finite element (FE) method has found several applications in emerging imaging modalities, especially microwave imaging which has been shown to be potentially useful in a number of areas including thermal estimation. In monitoring temperature distributions, the biological phenomena of temperature variations of tissue dielectric properties is exploited. By imaging these properties and their changes during such therapies as hyperthermia, temperature distributions can be deduced using difference imaging techniques. The authors focus on a microwave imaging problem where the hybrid element (HE) method is used in conjunction with a dual mesh scheme in an effort to image complex wavenumbers, k(2). The dual mesh scheme is introduced to improve the reconstructed images of tissue properties and is ideally suited for systems using FE methods as their computational base. Since the electric fields typically vary rapidly over a given body when irradiated by high-frequency electromagnetic sources, a dense mesh is needed for these fields to be accurately represented. Conversely, k(2) may be fairly constant over subregions of the body which would allow for a less dense sampling of this parameter in those regions. In the dual mesh system employed, the first mesh, which is uniformly dense, is used for calculating the electric fields over the body whereas the second mesh, which is nonuniform and less dense, is used for representing the k(2) distribution within the region of interest. The authors examine the 2-D TM polarization case for a pair of dielectric distributions on both a large and small problem to demonstrate the flexibility of the dual mesh method along with some of the difficulties associated with larger imaging problems. Results demonstrate the capabilities of the dual mesh concept in comparison to a single mesh approach for a variety of test cases, suggesting that the dual mesh method is critical for FE based image reconstruction where rapidly varying physical quantities are used to recover smoother property profiles, as can occur in microwave imaging of biological bodies. 相似文献
35.
36.
NMR studies have been carried out to determine the nature of the orientational ordering of N
2
in dilute solid N
2–Ar mixtures. The orientational ordering for cubic lattices (x(N
2)50%) was compared to that observed for the hexagonal lattice structures for 57 < x(N
2) < 75%. The NMR line shapes for the cubic structures were found to be sharply defined and could only be explained in terms of a narrow distribution of order parameters. This is in contrast to the quadrupolar glass state with a very broad order parameter distribution observed for the hexagonal structures. 相似文献
37.
Gary Allenby Kathy Dodgson Paul Harper Adel Kassam Michael Leam Ian Dale Elaine Sullivan 《Journal of The Association for Laboratory Automation》2001,6(5):48
Advances in the field of automation have meant hitherto complex manual cell-based assays can now be automated. These improvements have brought significant enhancements in throughput, data fidelity and consistency, and allowed a reallocation of constrained resources.Building upon these improvements, we have linked our automated cell-based screening system, Assay Platform™, to Activity Base (IDBS), a software package designed to automate the analysis of HTS data. Customisation of this package has resulted in software that can identify ‘active’ compounds and re-pick them ‘on the fly’ from the original compound plates for triplicate re-testing without operator intervention.Based on an operator initially defining ‘normal’ parameters for assay activity in Activity Base, combined with an automated quality control software module that checks data fidelity, wells containing ‘active’ compounds can be re-picked and re-tested at the end of an automated screening run. Automating cell-based assays has significantly improved productivity, and, with the synergism of Activity Base, has given us greater power to complete each screening run and report ‘active’ compounds to Chemistry more rapidly. This article presents our approach to the automation of cell-based Fluorescent Imaging Plate Reader (FLIPR) screening together with automated active re-test confirmation using Activity Base. 相似文献
38.
Sullivan CJ Venkataraman S Retterer ST Allison DP Doktycz MJ 《Ultramicroscopy》2007,107(10-11):934-942
Atomic force microscopy (AFM) provides a unique opportunity to study live individual bacteria at the nanometer scale. In addition to providing accurate morphological information, AFM can be exploited to investigate membrane protein localization and molecular interactions on the surface of living cells. A prerequisite for these studies is the development of robust procedures for sample preparation. While such procedures are established for intact bacteria, they are only beginning to emerge for bacterial spheroplasts. Spheroplasts are useful research models for studying mechanosensitive ion channels, membrane transport, lipopolysaccharide translocation, solute uptake, and the effects of antimicrobial agents on membranes. Furthermore, given the similarities between spheroplasts and cell wall-deficient (CWD) forms of pathogenic bacteria, spheroplast research could be relevant in biomedical research. In this paper, a new technique for immobilizing spheroplasts on mica pretreated with aminopropyltriethoxysilane (APTES) and glutaraldehyde is described. Using this mounting technique, the indentation and cell elasticity of glutaraldehyde-fixed and untreated spheroplasts of E. coli in liquid were measured. These values are compared to those of intact E. coli. Untreated spheroplasts were found to be much softer than the intact cells and the silicon nitride cantilevers used in this study. 相似文献
39.
40.
Lattice Boltzmann (LB) methods are used to simulate hydrodynamics, reaction and subsequent mass transfer in a disordered packed bed of catalyst particles at sub-pore length-scales. In contrast to previous studies, a variety of modifications are introduced in the LB method enabling particle Pe numbers up to 108, and hence realistic values of diffusivity, to be accessed. These include decoupling the hydrodynamics from mass transfer and the use of a rest fraction in the LB formulation of mass transfer. In addition the mass transfer simulations are modified to permit spatially varying values of diffusivity, essential to differentiate between intra- and inter-particle diffusivity (Dintra and Dinter, respectively). The simulation method is applied to both a disordered and ordered 2D packing for a range of Pe (15.6-1557.8) and Re (0.16-1.56) numbers, as well as various ratios of Dintra/Dinter (0-1), whilst simulating an esterfication reaction catalyzed by an ion-exchange resin. The value of Dintra is found to have limited effect, whilst reducing Pe number results in a considerable increase in overall conversion. The simulation method is then applied to a 3D lattice for which experimental conversion data is available. This experimental data is straddled by the simulation case of Dintra=0 and Dintra=Dinter, as expected. 相似文献