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61.
Matthias Winter Gregor Feiertag Anton Leidl Helmut Seidel 《Microsystem Technologies》2010,16(5):809-815
This paper describes the influence of a chip scale MEMS package (CSMP) on the acoustic behaviour of a silicon microphone.
The influence was calculated using an electro-mechanical–acoustical equivalent circuit. Standard packaging of microphones
using die bonding and wire bonding leads to a large front volume which acts as a Helmholtz resonator. This can dramatically
influence the frequency response of the microphone system by adding a second resonance. In the worst case this second resonance
is in the acoustic frequency range, thus degrading its performance in an unacceptable way. In case of the CSMP only a small
front volume is generated between the substrate and the flip-chipped microphone chip. Thus the resonance step-up is very small
compared to standard packages. Furthermore the frequency response can be flattened by optimizing the geometry of the small
sound holes in the substrate. By choosing an appropriate geometry of these sound holes the package can act as a low pass filter
where the cut-off frequency can be placed to the desired value of the acoustic spectrum. 相似文献
62.
Simon Schütz Henrik Abrahamsson Bengt Ahlgren Marcus Brunner 《Computer Networks》2010,54(7):1142-1154
The Internet Protocol (IP) has been proven very flexible, being able to accommodate all kinds of link technologies and supporting a broad range of applications. The basic principles of the original Internet architecture include end-to-end addressing, global routeability and a single namespace of IP addresses that unintentionally serves both as locators and host identifiers. The commercial success and widespread use of the Internet have lead to new requirements, which include Internetworking over business boundaries, mobility and multi-homing in an untrusted environment. Our approach to satisfy these new requirements is to introduce a new Internetworking layer, the node identity layer. Such a layer runs on top of the different versions of IP, but could also run directly on top of other kinds of network technologies, such as MPLS and 2G/3G PDP contexts. This approach enables connectivity across different communication technologies, supports mobility, multi-homing, and security from ground up. This paper describes the Node Identity Architecture in detail and discusses the experiences from implementing and running a prototype. 相似文献
63.
64.
Dipl.-Inf. Marina Berkovich Prof.?Dr. Jan Marco Leimeister Prof.?Dr. Helmut Krcmar 《WIRTSCHAFTSINFORMATIK》2011,53(6):357-370
In recent years, manufacturing companies and service providers have moved towards offering customer-specific problem solutions. These integrated bundles usually consist of hardware, software, and service components and are called product service systems (PSS) or hybrid products. Since the success of the resulting solution depends on the understanding of all requirements, requirements engineering (RE) has become a key factor. The article analyzes the state of the art of RE for PSS based on an extensive literature review in the domains of product-, software-, and service engineering. For this, criteria are derived from the characteristics of PSS and from the task area of RE in the life cycle of PSS. Based on these criteria we analyze the most established RE approaches for their suitability for PSS. An important finding is that integrated/interdisciplinary approaches for RE are missing. Moreover, the maturity of RE approaches in the three domains varies significantly. All analyzed approaches heavily rely on concepts and solution characteristics of their own domain so that a transfer to other domains is hardly possible. This literature review lays the foundation for successful RE for PSS and especially for future research aiming at combining and integrating RE approaches and models of product-, software-, and service engineering. Such requirement models could connect concepts of single domains and enable an integrated and seamless RE for PSS. 相似文献
65.
City councils hold meetings several times a week. There is a need for computer support at certain meetings. This paper examines the potential for group support systems for use in city council meetings and shows in what ways they can be helpful in pre-meeting and post-meeting activities. The study is based on 17 computer-supported city council meetings, carried out in Stuttgart, Kornwestheim and other cities as part of the Cuparla Project between 1996 and 1998. Three of these meetings are described in the paper as brief case studies. Following this, all 17 meeting sequences are evaluated and analysed. Guidelines have been developed from the results of the study for the introduction of group support systems in city council meetings. 相似文献
66.
2D/3D image registration on the GPU 总被引:1,自引:0,他引:1
A. Kubias F. Deinzer T. Feldmann D. Paulus B. Schreiber Th. Brunner 《Pattern Recognition and Image Analysis》2008,18(3):381-389
We present a method that performs a rigid 2D/3D image registration efficiently on the Graphical Processing Unit (GPU). As one main contribution of this paper, we propose an efficient method for generating realistic DRRs that are visually similar to x-ray images. Therefore, we model some of the electronic post-processes of current x-ray C-arm-systems. As another main contribution, the GPU is used to compute eight intensity-based similarity measures between the DRR and the x-ray image in parallel. A combination of these eight similarity measures is used as a new similarity measure for the optimization. We evaluated the performance and the precision of our 2D/3D image registration algorithm using two phantom models. Compared to a CPU + GPU algorithm, which calculates the similarity measures on the CPU, our GPU algorithm is between three and six times faster. In contrast to single similarity measures, our new similarity measure achieved precise and robust registration results for both phantom models. 相似文献
67.
Abstract— Coatings of indium tin oxide (ITO) nanoparticles on different flexible polymer substrates were investigated with respect to the achievable sheet resistance and their electrical behavior under oscillatory bending. As substrate materials, polyethyleneterephthalate (PET), polyethylenenaphthalate (PEN), polyetheretherketone (PEEK), and polyimide (PI) were chosen, the surface resistances on the different polymer substrates were compared as a function of annealing temperature and surface topography. The surface topography, which has a strong influence on the surface resistance, was characterized by means of a white‐light confocal (WL‐CF) microscope. On the PET substrate, which exhibits the smoothest surface, the coating of ITO nanoparticles shows the lowest sheet resistance of 2 kΩ/□ for a layer thickness of 3 μm and an annealing temperature of 200°C. Furthermore, the electrical behavior of coatings of ITO nanoparticles under oscillatory bending was investigated using a special device. These coatings show a cyclic change of the conductivity which can be explained by an alternating compression and extension of crack flanks under the applied stress. Due to the growing number of cracks with increasing number of cycles, a decrease of the conductivity is observed in the bent state as well as in the balanced state. For a small bending radii, the decrease of the conductivity is stronger due to more cracks caused by the higher tensile stresses in the layer. The electrical behavior of the coatings of the annealed ITO nanoparticles on PET films under oscillatory bending was compared with commercially available sputtered ITO coatings. The annealed coatings of ITO nanoparticles demonstrate better electrical properties under oscillatory bending than coatings of sputtered ITO. The different electrical behavior under oscillatory bending can be related to differences in crack formation. 相似文献
68.
Helmut Neukirchen Benjamin Zeiss Jens Grabowski 《International Journal on Software Tools for Technology Transfer (STTT)》2008,10(4):309-326
Experience with the development and maintenance of large test suites specified using the Testing and Test Control Notation (TTCN-3) has shown that it is difficult to construct tests that are concise with respect to quality aspects such as maintainability
or usability. The ISO/IEC standard 9126 defines a general software quality model that substantiates the term “quality” with
characteristics and subcharacteristics. The domain of test specifications, however, requires an adaption of this general model.
To apply it to specific languages such as TTCN-3, it needs to be instantiated. In this paper, we present an instantiation
of this model as well as an approach to assess and improve test specifications. The assessment is based on metrics and the
identification of code smells. The quality improvement is based on refactoring. Example measurements using our TTCN-3 tool
TRex demonstrate how this procedure is applied in practise.
B. Zeiss is supported by a Ph.D. scholarship from Siemens AG, Corporate Technology. 相似文献
69.
Helmut Reimer 《Datenschutz und Datensicherheit - DuD》2008,32(11):766-767
Ohne Zusammenfassung 相似文献
70.