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21.
A nonstandard integrodifferential approach to computation of eddy currents in linear structures with motion is presented. Described is a general continuous 3D model of the problem, together with the possibilities of forming corresponding numerical schemes. The methodology is illustrated by two examples.  相似文献   
22.
Food companies, governments, and societal organizations use an increasing number of food-choice motives to persuade consumers to buy food products, and the question which combinations of motives matter for which type of consumer has become of central relevance. In this study, we use a concomitant mixture-modeling approach to uncover consumer segments in terms of food-choice motives, using a nationwide sample in the Netherlands. The results reveal seven segments with distinct profiles and demonstrate that age and membership of environmental organizations play an essential role in segment membership probabilities. Our findings support the idea that information about non-food-related consumer behavior improves the identification of segments. In an additional analysis, we demonstrate how organizational membership also provides an effective way to access consumer segments as compared to diverse media outlets. We discuss the implications of our findings for segmentation practice.  相似文献   
23.
Flood events demonstrate devastating effects not only on materials and structures in contact with flowing surface water. Equally important is the behavior of foundations in interaction with subsoil. This contribution gives an overview of different phenomena which arise in subsoil and at the foundation level during the groundwater rise accompanied by several case histories related to cultural heritage. Possible geotechnical measures are discussed as well.  相似文献   
24.
The internationalization of technological capabilities in themultinational corporation has produced a growing number of conceptualframeworks that emphasize the ability to leverage innovationactivities in the international innovation network. In particular,it has been stressed that increasingly complex and diverse structuresgenerally provide opportunities to integrate and recombine knowledgeacross geographically dispersed units. The present study suggeststhat conceptual work has paid insufficient attention to therelationship between process and structure in the evolving internationalinnovation network. An in-depth, longitudinal study of ASEA/BrownBoveri/ABB underlines the importance of considering historicalgrowth processes and firm-specific events in evaluating themultinational's ability to integrate and recombine knowledgeon a global basis.  相似文献   
25.
Rendina et al. recently proposed the original configuration of an electromagnetic power sensor for microwaves and millimeter waves that is based on an optically interrogated all-silicon chip [Electron. Lett. 35, 1748 (1999)]. Here we theoretically analyze and discuss in detail the performances of such a new class of nonperturbing and wideband probe in terms of sensitivity, resolution, intrinsic detectivity, linearity, and response time. Good agreement between theory and experiments is demonstrated. In particular, minimum resolutions of approximately 1 mW/cm2 are obtained at frequencies beyond 10 GHz. The dependence of response on the geometrical and electromagnetic parameters of the sensing element is analyzed, and on this basis the possibility of achieving optimized configurations is discussed.  相似文献   
26.
A Scalable Architecture for MPEG-4 Wavelet Quantization   总被引:3,自引:0,他引:3  
Wavelet-based image compression has been adopted in MPEG-4 for visual texture coding. All wavelet quantization schemes in MPEG-4—Single Quantization (SQ), Multiple Quantization (MQ) and Bi-level Quantization—use Embedded Zero Tree (EZT) coding followed by an adaptive arithmetic coder for the compression and quantization of a wavelet image. This paper presents the OZONE chip, a dedicated hardware coprocessor for EZT and arithmetic coding. Realized in a 0.5 m CMOS technology and operating at 32 MHz, the EZT coder is capable of processing up to 25.6 Mega pixel-bitplanes per second. This is equivalent to the lossless compression of 31.6 8-bit grayscale CIF images (352 × 288) per second. The adaptive arithmetic coder processes up to 10 Mbit per second. The combination of the performance of the EZT coder and the arithmetic coder allows the OZONE to perform visual-lossless compression of more than 30 CIF images per second. Due to its novel and scalable architecture, parallel operation of multiple OZONEs is supported. The OZONE functionality is demonstrated on a PC-based compression system.  相似文献   
27.
The rate of convergence of the finite element method is a function of the strategy by which the number of degrees-of-freedom are increased. Alternative stragegies are examined in the light of recent theoretical results and computational experience.  相似文献   
28.
An ozone monitoring network was set up using passive samplers and biological mini-stations of two clones of white clover (Trifolium repens L. cv. Regal), NC-R (O(3)-resistant) and NC-S (O(3)-sensitive). This paper reports on a pilot study performed in the period June-October 1999 in the Rome municipal area by using five biomonitoring mini-stations and ozone passive samplers with a new nitrite based design. This combined methodology can be used to obtain information on the biological implications of the injury due to tropospheric ozone. The two techniques can integrate data for the short-medium period and can be placed in different urban and rural sites, proving to be a very useful tool for ozone concentration mapping.  相似文献   
29.
In this paper, we address the cost versus accuracy capabilities for the generalized FEM (GFEM) which was developed in (Comput. Methods Appl. Mech. Eng. 2003; 192 :3109–3161, Int. J. Numer. Meth. Engng 2004; 60 :1639–1672, Ph.D. Thesis, Texas A&M University, College Station, TX, August 2003 (Advisor: T. Strouboulis)), and also the construction of two‐sided a posteriori error estimates, which can be used to assess the achieved accuracy at all levels of the method. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
30.
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