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111.
112.
Timo Baur Rebecca Breu Tibor Kálmán Tobias Lindinger Anne Milbert Gevorg Poghosyan Helmut Reiser Mathilde Romberg 《Journal of Grid Computing》2009,7(3):319-333
In many Grid infrastructures different kinds of information services are in use, which utilize different incompatible data structures and interfaces to encode and provide their data. Homogeneous monitoring of these infrastructures with the monitoring data being accessible everywhere independently of the middleware which provided it, is the basis for a consistent status reporting on the Grids’ resources and services. Thus, interoperability or interoperation between the different information services in a heterogeneous Grid infrastructure is required. Monitoring data must contain the identity of the affected Virtual Organization (VO) so that it can be related to the resources and services the VO has allocated to enable VO-specific information provision. This paper describes a distributed architecture for an interoperable information service, which combines data unification and categorization with policies for VO membership, VO resource management and data transformations. This service builds the basis for an integrated and interoperating monitoring of Grids, which provide their data to more than one VO and utilize heterogeneous information services. 相似文献
113.
Helmut Reimer 《Datenschutz und Datensicherheit - DuD》2009,33(8):509-516
DuD Report
DuD Report 相似文献114.
Christoph Riedl Tilo Böhmann Michael Rosemann Helmut Krcmar 《Information Systems and E-Business Management》2009,7(2):199-221
Service-oriented architectures and Web services mature and have become more widely accepted and used by industry. This growing
adoption increased the demands for new ways of using Web service technology. Users start re-combining and mediating other
providers’ services in ways that have not been anticipated by their original provider. Within organisations and cross-organisational
communities, discoverable services are organised in repositories providing convenient access to adaptable end-to-end business
processes. This idea is captured in the term Service Ecosystem. This paper addresses the question of how quality management
can be performed in such service ecosystems. Service quality management is a key challenge when services are composed of a
dynamic set of heterogeneous sub-services from different service providers. This paper contributes to this important area
by developing a reference model of quality management in service ecosystems. We illustrate the application of the reference
model in an exploratory case study. With this case study, we show how the reference model helps to derive requirements for
the implementation and support of quality management in an exemplary service ecosystem in public administration. 相似文献
115.
The estimation of dynamically evolving ellipsoids from noisy lower-dimensional projections is examined. In particular, this work describes a model-based approach using geometric reconstruction and recursive estimation techniques to obtain a dynamic estimate of left-ventricular ejection fraction from a gated set of planar myocardial perfusion images. The proposed approach differs from current ejection fraction estimation techniques both in the imaging modality used and in the subsequent processing which yields a dynamic ejection fraction estimate. For this work, the left ventricle is modeled as a dynamically evolving three-dimensional (3-D) ellipsoid. The left-ventricular outline observed in the myocardial perfusion images is then modeled as a dynamic, two-dimensional (2-D) ellipsoid, obtained as the projection of the former 3-D ellipsoid. This data is processed in two ways: first, as a 3-D dynamic ellipsoid reconstruction problem; second, each view is considered as a 2-D dynamic ellipse estimation problem and then the 3-D ejection fraction is obtained by combining the effective 2-D ejection fractions of each view. The approximating ellipsoids are reconstructed using a Rauch-Tung-Striebel smoothing filter, which produces an ejection fraction estimate that is more robust to noise since it is based on the entire data set; in contrast, traditional ejection fraction estimates are based only on true frames of data. Further, numerical studies of the sensitivity of this approach to unknown dynamics and projection geometry are presented, providing a rational basis for specifying system parameters. This investigation includes estimation of ejection fraction from both simulated and real data. 相似文献
116.
M. B. Maple M. C. de Andrade J. Herrmann Y. Dalichaouch D. A. Gajewski C. L. Seaman R. Chau R. Movshovich M. C. Aronson R. Osborn 《Journal of Low Temperature Physics》1995,99(3-4):223-249
Experimental efforts to characterize and develop an understanding of non Fermi liquid (NFL) behavior at low temperature in f-electron materials are reviewed for three f-electron systems: M1–xUxPd3 (M = Sc, Y), U1–xThxPd2Al3, and UCu5–xPdx. The emerging systematics of NFL behavior in f-electron systems, based on the present sample of nearly ten f-electron systems, is updated. Many of the f-electron systems exhibit the following temperature dependences of the electrical resistivity p, specific heat C, and magnetic susceptibility for T T0, where To is a characteristic temperature: P(T) 1 –aT/T
0, where a < 0 or > 0, C(T)/T (-1/T
o) In (T/bT
0), and (T) 1 –c(T/To)1/2. In several of the f-electron systems, the characteristic temperature To can be identified with the Kondo temperature Tk. 相似文献
117.
Structure and Magnetic Property Control of Copper Hydroxide Acetate by Non‐Classical Crystallization 下载免费PDF全文
RuiQi Song Theodora Krasia‐Christoforou Christian Debus Helmut Cölfen 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(9)
Copper hydroxide acetate (CHA), one layered hydroxide compound with tunable magnetism, attracts great interest because of its potential applications in memory devices. However, ferromagnetism for CHA is only demonstrated by means of GPa pressure. Herein, a new method is reported, involving the combination of different crystallization pathways to control crystallization of amorphous CHA toward the formation of CHA/polymer composites with tunable magnetic properties and even a tunability that can be tested at room temperature. By using poly[(ethylene glycol)6 methyl ether methacrylate]‐block‐poly[2‐(acetoacetoxy) ethyl methacrylate] (PEGMA‐b‐PAEMA) diblock copolymers as additives in combination with a post‐treatment process by ultracentrifugation, it is demonstrated that CHA and PEGMA‐b‐PAEMA form composites exhibiting different magnetic properties, depending on CHA in‐plane nanostructures. Analytical characterization reveals that crystallization of CHA is induced by ultracentrifugation, during which CHA nanostructures can be well controlled by changing the degrees of polymerization of the PEGMA and PAEMA blocks and their block length ratios. These findings not only present the first example of using crystallization from polymer stabilized amorphous precursors toward the generation of magnetic nanomaterials with tunable magnetism but also pave the way for the future design of functional composite materials. 相似文献
118.
119.
This paper proposes a scenario-based two-stage stochastic programming model with recourse for master production scheduling under demand uncertainty. We integrate the model into a hierarchical production planning and control system that is common in industrial practice. To reduce the problem of the disaggregation of the master production schedule, we use a relatively low aggregation level (compared to other work on stochastic programming for production planning). Consequently, we must consider many more scenarios to model demand uncertainty. Additionally, we modify standard modelling approaches for stochastic programming because they lead to the occurrence of many infeasible problems due to rolling planning horizons and interdependencies between master production scheduling and successive planning levels. To evaluate the performance of the proposed models, we generate a customer order arrival process, execute production planning in a rolling horizon environment and simulate the realisation of the planning results. In our experiments, the tardiness of customer orders can be nearly eliminated by the use of the proposed stochastic programming model at the cost of increasing inventory levels and using additional capacity. 相似文献
120.
Microfluidic Manipulation of Core/Shell Nanoparticles for Oral Delivery of Chemotherapeutics: A New Treatment Approach for Colorectal Cancer 下载免费PDF全文
Mohammad Mahdi Hasani‐Sadrabadi Shahrouz Taranejoo Erfan Dashtimoghadam Ghasem Bahlakeh Fatemeh Sadat Majedi Jules John VanDersarl Mohsen Janmaleki Fatemeh Sharifi Arnaud Bertsch Kerry Hourigan Lobat Tayebi Philippe Renaud Karl I. Jacob 《Advanced materials (Deerfield Beach, Fla.)》2016,28(21):4134-4141