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排序方式: 共有8023条查询结果,搜索用时 31 毫秒
61.
A review of The Principles of Beautiful Web Design by Jason Beaird. The book aims to cover the demand to build Web sites by targeting designers who want to learn how to make Web sites look more attractive. 相似文献
62.
Semantic Web Mining: State of the art and future directions 总被引:2,自引:0,他引:2
Semantic Web Mining aims at combining the two fast-developing research areas Semantic Web and Web Mining. This survey analyzes the convergence of trends from both areas: More and more researchers are working on improving the results of Web Mining by exploiting semantic structures in the Web, and they make use of Web Mining techniques for building the Semantic Web. Last but not least, these techniques can be used for mining the Semantic Web itself.The Semantic Web is the second-generation WWW, enriched by machine-processable information which supports the user in his tasks. Given the enormous size even of today’s Web, it is impossible to manually enrich all of these resources. Therefore, automated schemes for learning the relevant information are increasingly being used. Web Mining aims at discovering insights about the meaning of Web resources and their usage. Given the primarily syntactical nature of the data being mined, the discovery of meaning is impossible based on these data only. Therefore, formalizations of the semantics of Web sites and navigation behavior are becoming more and more common. Furthermore, mining the Semantic Web itself is another upcoming application. We argue that the two areas Web Mining and Semantic Web need each other to fulfill their goals, but that the full potential of this convergence is not yet realized. This paper gives an overview of where the two areas meet today, and sketches ways of how a closer integration could be profitable. 相似文献
63.
Andreas Rottmann 《Datenschutz und Datensicherheit - DuD》2006,30(3):153-154
Die elektronische Gesundheitskarte (eGK) bietet viele neue M?glichkeiten für eine vernetzte, effiziente Gesundheitsversorgung.
Komplexe ≫Card and Application Management Systeme≪ (CAMS) gew?hrleisten im Hintergrund Funktionsf?higkeit und Sicherheit —
von der Ausgabe der Karte bis zu ihrer Erneuerung. 相似文献
64.
A modern concept of cost-effective digital signal processing hardware for measuring and analysing data from experiments investigating turbulent two-phase flows is presented. Using an array processor together with an appropriate analog-to-digital converter, conventional turbulence characteristics such as turbulence spectra, correlation functions, turbulence intensities and — scales can be evaluated in real time. 相似文献
65.
M Müller-Schimpfle K Ohmenhaüser P Stoll K Dietz CD Claussen 《Canadian Metallurgical Quarterly》1997,203(1):145-149
PURPOSE: To quantify how frequently mesenteric adenitis clinically mimics appendicitis and to determine its appearance at computed tomography (CT). MATERIALS AND METHODS: The medical records of 651 consecutive patients with an admission diagnosis of appendicitis were reviewed to determine how often mesenteric adenitis was the discharge diagnosis. The CT scans of a separate group of 18 patients with a discharge diagnosis of mesenteric adenitis were reviewed. These patients were part of a group of 100 consecutive patients prospectively evaluated with CT of the appendix for clinically suspected appendicitis. RESULTS: Fifty of 651 patients (7.7%) with an admission diagnosis of appendicitis had a discharge diagnosis of mesenteric adenitis. Mesenteric adenitis constituted 50 of the 252 (19.8%) discharge diagnoses other than appendicitis. All 18 CT scans of mesenteric adenitis showed three or more nodes that measured at least 5 mm in shortest axis clustered in the right lower quadrant, with a normal appendix identified. Eight patients had associated ileal or ileocecal wall thickening. CONCLUSION: Mesenteric adenitis is an important clinical mimic of appendicitis. It appears at CT as clustered, enlarged mesenteric lymph nodes with a normal appendix, and there may be associated ileitis or ileocolitis noted. 相似文献
66.
Gerosa G. Gary S. Dietz C. Dac Pham Hoover K. Alvarez J. Sanchez H. Ippolito P. Tai Ngo Litch S. Eno J. Golab J. Vanderschaaf N. Kahle J. 《Solid-State Circuits, IEEE Journal of》1994,29(12):1440-1454
A 28 mW/MHz at 80 MHz structured-custom RISC microprocessor design is described. This 32-b implementation of the PowerPC architecture is fabricated in a 3.3 V, 0.5 μm, 4-level metal CMOS technology, resulting in 1.6 million transistors in a 7.4 mm by 11.5 mm chip size. Dual 8-kilobyte instruction and data caches coupled to a high performance 32/64-b system bus and separate execution units (float, integer, loadstore, and system units) result in peak instruction rates of three instructions per clock cycle. Low-power design techniques are used throughout the entire design, including dynamically powered down execution units. Typical power dissipation is kept under 2.2 W at 80 MHz. Three distinct levels of software-programmable, static, low-power operation-for system power management are offered, resulting in standby power dissipation from 2 mW to 350 mW. CPU to bus clock ratios of 1×, 2×, 3×, and 4× are implemented to allow control of system power while maintaining processor performance. As a result, workstation level performance is packed into a low-power, low-cost design ideal for notebooks and desktop computers 相似文献
67.
Andreas Ruh 《Corrosion Science》2006,48(3):679-695
Thermogravimetric (TG) experiments have been carried out to study the kinetics of hot corrosion of Fe, Cr and Ni, covered by a molten KCl-ZnCl2 mixture of a composition close to the eutectic (50 mol% KCl-50 mol% ZnCl2). Furthermore binary and ternary phase diagrams were calculated in order to describe the corrosion process. The tests were conducted at a temperature of 320 °C in an atmosphere consisting of argon and oxygen. For iron different stages are observed in a TG curve. They can be attributed to the different reaction steps of iron chloride formation (incubation phase), oxide precipitation (linear stage) and scale formation (parabolic or logarithmic stage). Based on these observations a model, described by Spiegel [A. Spiegel, Molten Salt Forum 7 (2003) 253], is confirmed. For Cr and Ni these stages are not observed. At 8 vol% O2 only slight oxidation of Cr and Ni was observed accompanied by evaporation of the salt deposit. At 16 vol% O2 the rate of oxidation increases and the experiments yield a curve that is either parabolic or logarithmic for both Ni and Cr. As a result it is shown that the solubility of iron chloride in the KCl-ZnCl2 melt is higher than the solubility of nickel chloride and chromium (III) chloride in the KCl-ZnCl2 melt. This enables a higher diffusibility of iron chloride to the upper region of the melt where a higher oxygen partial pressure (p(O2)) is present leading to a higher oxidation rate of iron. 相似文献
68.
69.
Fluorescence microscopy techniques have become important tools in mitosis research. The well-known disadvantages of fluorescence microscopy, rapid bleaching, phototoxicity and out-of-focus contributions blurring the in-focus image are obstacles which still need to be overcome. Confocal fluorescence microscopy has the potential to improve our capabilities of analyzing cells, because of its excellent depth-discrimination and image processing power. We have been using a confocal fluorescence microscope for the study of the mechanism of poleward chromosome movement, and report here (1) a cell preparation technique, which allows labeling of fixation sensitive spindle antigens with acceptable microtubule preservation; (2) the use of image processing methods to represent the spatial distribution of various labeled elements in pseudocolour; (3) a novel immunoelectron microscopic labeling method for microtubules, which allows the visualization of their distribution in semithin sections at low magnification; and (4) a first attempt to study microtubule dynamics with a confocal fluorescence microscope in living cells, microinjected with rhodamine labeled tubulin. Our experience indicates that confocal fluorescence microscopy provides real advantages for the study of spatial colocalization of antigens in the mitotic spindle. It does not, however, overcome the basic limits of resolution of the light microscope. Therefore, it has been necessary to use an electron microscopic method. Our preliminary results with living cells show that it is possible to visualize the entire microtubule network in stereo, but that the sensitivity of the instrument is still too low to perform dynamic time studies. It will be worthwhile to further develop this new type of optical instrumentation and explore its usefulness on both fixed and living cells. 相似文献
70.
Andreas Kleinert 《NTM》2006,14(3):174-177
In the late 19th and early 20th centuries, many prominent German and Austrian scientists declined the election as a member
of the Kaiserliche Leopoldinisch-Carolinische Deutsche Akademie der Naturforscher (in short: Leopoldina) because they were
not willing to pay the entrance and membership fees of about one fifth of the monthly salary of a full professor. Many of
theses candidates simply did not answer to the president’s notification of being elected. Some of them came up with ,,various
reasons not to be discussed”, or referred to their individual financial situation.The physicist Heinrich Hertz, who had become
famous by the discovery of electromagnetic waves in the late 1880ies, was the only elected candidate who protested bluntly
against what he considered as an unworthy procedure. Although it would not have been a much of a burden for him to afford
the requested entrance and membership fees, he refused to adhere to an association whose statues combined the award of an
academic distinction with the obligation of financial support. In two letters addressed to Leopoldina President Carl Hermann
Knoblauch,Hertz gave his reasons for declining his election to the academy. In the present article, Hertz’s letters to Knoblauch
are fully published for the first time.
相似文献