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71.
Niklas Blum Thomas Magedanz Florian Schreiner Sebastian Wahle 《Journal of Network and Systems Management》2009,17(1-2):33-52
Although IP Multimedia Subsystem (IMS) based Next Generation Networks (NGNs) are already emerging as the common session control platform for converging fixed, mobile and cable networks, harmonized solutions for the management of these converged platforms have still got to be developed. This document describes a hands-on approach to NGN Management. Started with IMS specific management systems, succeeding research had to take into account the importance of the management of NGN SDPs as well. This work shows that the hybrid nature of an NGN, where services can be delivered at the IMS layer, by SIP signaling mechanisms, as well as at the SDP, via Web Services, requires a harmonized management approach. Taking into account Service Oriented Architecture (SOA) principles and policy based model driven architectures, this work shows that a unification of service composition and service management already at the workflow creation level, bares significant benefits in terms of automation and harmonization. Following the SOA paradigm, the approach presented here does not differentiate between business process management (BPM) and management process management. Focusing on Telemanagement Forum’s enhanced Telecom Operations Map service fulfillment and service assurance operations, this document describes an New Generation Software and Services (NGOSS) based implementation of a unified Operation Support System (OSS) for NGNs that encompasses many problems of former stovepipe management solutions in terms of automation, flexibility and manageability. 相似文献
72.
Sebastian Klenk Jürgen Dippon Peter Fritz Gunther Heidemann 《Information Systems Frontiers》2009,11(4):391-403
Medical data mining is currently actively pursued in computer science and statistical research but not in medical practice.
The reasons therefore lie in the difficulties of handling and statistically analyzing medical data. We have developed a system
that allows practitioners in the field to interactively analyze their data without assistance of statisticians or data mining
experts. In the course of this paper we will introduce data mining of medical data and show how this can be achieved for survival
data. We will demonstrate how to solve common problems of interactive survival analysis by presenting the Online Clinical
Data Mining (OCDM) system. Thereby the main focus is on similarity based queries, a new method to select similar cases based
on their covariables and the influence of these on their survival. 相似文献
73.
The current Web Services Agreement specification draft proposes a simple request-response protocol for agreement creation
only addressing bilateral offer exchanges. This paper proposes a framework augmenting this WS-Agreement to enable negotiations
according to a variety of bilateral and multilateral negotiation protocols. The framework design is based on a thorough analysis
of taxonomies for negotiations from the literature in order to allow for capturing a variety of different negotiation models
within a single, WS-Agreement compatible, framework. In order to provide for the intended flexibility, the proposed protocol
takes a two-stage approach: a meta-protocol is conducted among interested parties to agree on a common negotiation protocol
first before the real negotiation is carried out in the second step due to the protocol established in the first step. 相似文献
74.
Thin films of the metal glass Ti88Si12 were produced by evaporation and characterized by AFM and conductivity measurements. Thin Ti88Si12 support films for electron microscopy were prepared by coating standard EM grids with evaporated films floated off mica, and characterized by electron imaging and electron diffraction. At room temperature, the specific resistance of a thin TiSi film was 10(6) times lower than that of an amorphous carbon film. At 77K, the specific resistance of TiSi films decreased, whereas that of carbon became immeasurably high. The effective scattering cross-section of TiSi and amorphous carbon for 120 kV electrons is roughly equal, but TiSi films for routine use can be approximately 10 times thinner due to their high mechanical strength, so that they would contribute less background noise to the image. Electron diffraction of purple membrane on a TiSi substrate confirmed that the support film was amorphous, and indicated that the high-resolution order of the biological sample was preserved. Electron micrographs of TiSi films tilted by 45 degrees relative to the electron beam recorded at approximately 4 K indicated that the incidence of beam-induced movements was reduced by 50% compared to amorphous carbon film under the same conditions. The success rate of recording high-resolution images of purple membranes on TiSi films was close to 100%. We conclude that TiSi support films are ideal for high-resolution electron cryo-microscopy (cryo-EM) of biological specimens, as they reduce beam-induced movement significantly, due to their high electrical conductivity at low temperature and their favorable mechanical properties. 相似文献
75.
A method and an experimental setup have been developed for measuring absolute photoemission cross sections for electron-impact-induced line radiation in the vacuum ultraviolet (VUV). Unparalleled low uncertainties for the cross sections were achieved mainly from the use of the Berlin electron storage ring as a primary standard source in the VUV for the determination of the responsivity of the spectrometer-detector system used and from the use of a spinning rotor gauge as a secondary standard for the determination of the target gas density. As the first result we present a photoemission cross section for the Ar II 3s3p(6)(2)S(?)-3s(2)3p(5)(2)p?(3/2) transition at 91.98 nm for 2-keV electron-impact energy of 1.167 × 10(-18) cm(2) with a relative uncertainty of 4.4% (√3σ value). This low uncertainty demonstrates the suitability of the setup for further cross-section measurements. 相似文献
76.
Sebastian Ronneberger Junfang Zhang Yuxin Liu Felix F. Loeffler 《Advanced functional materials》2023,33(17):2210116
Tagging, tracking, or validation of products are often facilitated by inkjet-printed optical information labels. However, this requires thorough substrate pretreatment, ink optimization, and often lacks in printing precision/resolution. Herein, a printing method based on laser-driven deposition of solid polymer ink that allows for printing on various substrates without pretreatment is demonstrated. Since the deposition process has a precision of <1 µm, it can introduce the concept of sub-positions with overlapping spots. This enables high-resolution fluorescent labels with comparable spot-to-spot distance of down to 15 µm (444,444 spots cm−2) and rapid machine learning-supported readout based on low-resolution fluorescence imaging. Furthermore, the defined thickness of the printed polymer ink spots can be used to fabricate multi-channel information labels. Additional information can be stored in different fluorescence channels or in a hidden topography channel of the label that is independent of the fluorescence. 相似文献
77.
Akesson Benny Nasri Mitra Nelissen Geoffrey Altmeyer Sebastian Davis Robert I. 《Real-Time Systems》2022,58(3):358-398
Real-Time Systems - This paper presents results and observations from a survey of 120 industry practitioners in the field of real-time embedded systems. The survey provides insights into the... 相似文献
78.
Writing with Fluid: Structuring Hydrogels with Micrometer Precision by AFM in Combination with Nanofluidics 下载免费PDF全文
Nicolas Helfricht Andreas Mark Marina Behr Andreas Bernet Hans‐Werner Schmidt Georg Papastavrou 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(31)
Hydrogels have many applications in biomedical surface modification and tissue engineering. However, the structuring of hydrogels after their formation represents still a major challenge, in particular due to their softness. Here, a novel approach is presented that is based on the combination of atomic force microscopy (AFM) and nanofluidics, also referred to as FluidFM technology. Its applicability is demonstrated for supramolecular hydrogel films that are prepared from low‐molecular weight hydrogelators, such as derivates of 1,3,5‐benzene tricarboxamides (BTAs). BTA films can be dissolved selectively by ejecting alkaline solution through the aperture of a hollow AFM‐cantilever connected to a nanofluidic controller. The AFM‐based force control is essential in preventing mechanical destruction of the hydrogels. The resulting “chemical writing” process is studied in detail and the influence of various parameters, such as applied pressure and time, is validated. It is demonstrated that the achievable structuring precision is primarily limited by diffusion and the aperture dimensions. Recently, various additive techniques have been presented to pattern hydrogels. The here‐presented subtractive approach can not only be applied to structure hydrogels from the large class of reversibly formed gels with superior resolution but would also allow for the selective loading of the hydrogels with active substances or nanoparticles. 相似文献
79.
Bioimaging: Shaping Luminescent Properties of Yb3+ and Ho3+ Co‐Doped Upconverting Core–Shell β‐NaYF4 Nanoparticles by Dopant Distribution and Spacing (Small 47/2017) 下载免费PDF全文
80.
Hector Archila Sebastian Kaminski David Trujillo Edwin Zea Escamilla Kent A. Harries 《Materials and Structures》2018,51(4):102
The use of small diameter whole-culm (bars) and/or split bamboo (a.k.a. splints or round strips) has often been proposed as an alternative to relatively expensive reinforcing steel in reinforced concrete. The motivation for such replacement is typically cost—bamboo is readily available in many tropical and sub-tropical locations, whereas steel reinforcement is relatively more expensive—and more recently, the drive to find more sustainable alternatives in the construction industry. This review addresses such ‘bamboo-reinforced concrete’ and assesses its structural and environmental performance as an alternative to steel reinforced concrete. A prototype three bay portal frame, that would not be uncommon in regions of the world where bamboo-reinforced concrete may be considered, is used to illustrate bamboo reinforced concrete design and as a basis for a life cycle assessment of the same. The authors conclude that, although bamboo is a material with extraordinary mechanical properties, its use in bamboo-reinforced concrete is an ill-considered concept, having significant durability, strength and stiffness issues, and does not meet the environmentally friendly credentials often attributed to it. 相似文献