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51.
52.
Richard O. Sinnott Christopher Bayliss Andrew Bromage Gerson Galang Yikai Gong Philip Greenwood Glenn Jayaputera Davis Marques Luca Morandini Ghazal Nogoorani Hossein Pursultani Muhammad Sarwar William Voorsluys Ivo Widjaja 《Journal of Grid Computing》2016,14(4):603-618
Big data technologies and a range of Government open data initiatives provide the basis for discovering new insights into cities; how they are planned, how they managed and the day-to-day challenges they face in health, transport and changing population profiles. The Australian Urban Research Infrastructure Network (AURIN – www.aurin.org.au) project is one example of such a big data initiative that is currently running across Australia. AURIN provides a single gateway providing online (live) programmatic access to over 2000 data sets from over 70 major and typically definitive data-driven organizations across federal and State government, across industry and across academia. However whilst open (public) data is useful to bring data-driven intelligence to cities, more often than not, it is the data that is not-publicly accessible that is essential to understand city challenges and needs. Such sensitive (unit-level) data has unique requirements on access and usage to meet the privacy and confidentiality demands of the associated organizations. In this paper we highlight a novel geo-privacy supporting solution implemented as part of the AURIN project that provides seamless and secure access to individual (unit-level) data from the Department of Health in Victoria. We illustrate this solution across a range of typical city challenges in localized contexts around Melbourne. We show how unit level data can be combined with other data in a privacy-protecting manner. Unlike other secure data access and usage solutions that have been developed/deployed, the AURIN solution allows any researcher to access and use the data in a manner that meets all of the associated privacy and confidentiality concerns, without obliging them to obtain ethical approval or any other hurdles that are normally put in place on access to and use of sensitive data. This provides a paradigm shift in secure access to sensitive data with geospatial content. 相似文献
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Scanning surfaces using a beam of noncharged atoms or molecules allows for especially nondestructive and low-energy surface imaging, with the potential to obtain new information about surfaces that cannot be easily obtained otherwise. We have developed a new approach, operating with the sample at a close working distance from an aperture, the need for optics to focus the beam is obviated. Compared to more complex approaches, the theoretical performance has no other disadvantage than the short working distance. Resolution of 1.5 μm has been achieved, and submicron resolution appears to be practical. Construction of the microscope and results are presented, including first images done in reflection mode, theory for optimization of the design and avenues for future improvement. 相似文献
56.
Philip N. James 《Information Systems Management》2013,30(4):83-86
Abstract MORE THAN 50 PERCENT OF firms are expected to use IT outsourcing in 2006. the sourcing issue is among the top five agenda items for IT executives, as the amount of such outsourcing grows, its impact on the economies of companies and nations increases and political controversy over the consequent jobs lost to off-shore outsourcing heightens. Thus, outsourcing is, and will likely continue to be, a hot professional and political topic and a major determinant of the future of IT. 相似文献
57.
In this paper we introduce the constrained tetrahedralization as a new acceleration structure for ray tracing. A constrained tetrahedralization of a scene is a tetrahedralization that respects the faces of the scene geometry. The closest intersection of a ray with a scene is found by traversing this tetrahedralization along the ray, one tetrahedron at a time. We show that constrained tetrahedralizations are a viable alternative to current acceleration structures, and that they have a number of unique properties that set them apart from other acceleration structures: constrained tetrahedralizations are not hierarchical yet adaptive; the complexity of traversing them is a function of local geometric complexity rather than global geometric complexity; constrained tetrahedralizations support deforming geometry without any effort; and they have the potential to unify several data structures currently used in global illumination. 相似文献
58.
Increasingly, software systems are constructed by integrating and composing multiple existing applications. The resulting complexity increases the need for self-management of the system. However, adding autonomic behavior to composite systems is difficult, especially when the constituent components are heterogeneous and they were not originally designed to support such interactions. Moreover, entangling the code for self-management with the code for the business logic of the original applications may actually increase the complexity of the systems, counter to the desired goal. In this paper, we address autonomization of composite systems that use CORBA, one of the first widely used middleware platforms introduced more than 17 years ago that is still commonly used in numerous systems. We propose a model, called Adaptive CORBA Template (ACT), that enables autonomic behavior to be added to CORBA applications automatically and transparently, that is, without requiring any modifications to the code implementing the business logic of the original applications. To do so, ACT uses “generic” interceptors, which are added to CORBA applications at startup time and enable autonomic behavior to be introduced later at runtime. We have developed ACT/J, a prototype of ACT in Java. We describe a case study in which ACT/J is used to introduce three types of autonomic behavior (self-healing, self-optimization, and self-configuration) to a distributed surveillance application. 相似文献
59.
The design of systems for dynamic response may involve constraints that need to be satisfied over an entire time interval
or objective functions evaluated over the interval. Efficiently performing the constrained optimization is challenging, since
the typical response is implicitly linked to the design variables through a numerical integration of the governing differential
equations. Evaluating constraints is costly, as is the determination of sensitivities to variations in the design variables.
In this paper, we investigate the application of a temporal spectral element method to the optimization of transient and time-periodic
responses of fundamental engineering systems. Through the spectral discretization, the response is computed globally, thereby
enabling a more explicit connection between the response and design variables and facilitating the efficient computation of
response sensitivities. Furthermore, the response is captured in a higher order manner to increase analysis accuracy. Two
applications of the coupling of dynamic response optimization with the temporal spectral element method are demonstrated.
The first application, a one-degree-of-freedom, linear, impact absorber, is selected from the auto industry, and tests the
ability of the method to treat transient constraints over a large-time interval. The second application, a related mass-spring-damper
system, shows how the method can be used to obtain work and amplitude optimal time-periodic control force subject to constraints
over a periodic time interval.
This research was performed while the first author held a National Research Council Research Associateship Award at the Air
Force Research Laboratory.
An early version of this paper was presented at the 46th AIAA Aerospace Sciences Meeting and Exhibit, Jan 7–10, 2008, Reno,
Nevada. 相似文献
60.
Qi Jiyang Gao Yan Hu Yao Wang Xinggang Liu Xiaoyu Bai Xiang Belongie Serge Yuille Alan Torr Philip H. S. Bai Song 《International Journal of Computer Vision》2022,130(8):2022-2039
International Journal of Computer Vision - Can our video understanding systems perceive objects when a heavy occlusion exists in a scene? To answer this question, we collect a large-scale dataset... 相似文献