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21.
User-centered approach to adaptive interfaces 总被引:2,自引:0,他引:2
T. Kühme 《Knowledge》1993,6(4):239-248
Both adaptive and adaptable user interfaces are intended to fit the needs of individual users and their tasks better. A problem with these interfaces is that users must have and use additional knowledge, either to understand the automatic, system-driven adaptations or to adapt the interface on their own. Beyond these two extreme approaches, an automatically self-adapting system and a user manually adapting the system, the approach introduced in this paper strives for a third option, in which users are able to tell the system how to adapt itself. Accordingly, methods include adaptive adaptation (i.e. modifying the adaptation strategies) and implicit adaptation (i.e. changing the underlying models). The applicability of these findings is illustrated in the context of an adaptive action prompting environment. 相似文献
22.
A numerically efficient algorithm for estimating the time delay from observations of a stationary narrowband signal and its delayed version is investigated. Quadrature sampling, a variant of bunched sampling, is applied to estimate samples of the quadrature components of the cross-covariance function of the two signals. The baseband magnitude squared of this function can be maximized for time delay estimation. Because the time delay is unknown, the baseband cross-covariance function cannot be interpolated from the estimated samples. Numerical maximization of the samples' magnitude squared and quadratic interpolation, however, results in a reasonable time delay estimate. 相似文献
23.
Summary Aliphatic polyformamidines have been synthesized by reaction of aliphatic diamines with triethyl orthoformate in presence of catalytic amounts of acetic acid. The reaction has been carried out in DMSO at 180°C. The polymer structure has been confirmed by IR and NMR spectroscopy. For determination of molecular weights 1H NMR end group signals have been used. 相似文献
24.
G B?hme 《Canadian Metallurgical Quarterly》1976,24(3):94-101
To better understand the assessment of difficulties in verbal communication it is considered to explain language and speech development in relation to motor function. The aetiology, diagnosis, prognosis and treatment of language disorders and their common characteristics are discussed. The otolaryngologist must expect an increase in the number of such cases and should initiate prompt and adequate treatment. 相似文献
25.
Summary New aromatic polymers containing formamidine groups were prepared by high temperature solution polycondensation of triethyl orthoformate with various aromatic diamines. The resulting polyformamidines were characterized by elemental analysis, IR' and 1H NMR spectroscopy, viscosity measurements, thermogravimetry, DSC- and WAXS measurements. With few exceptions aromatic polyformamidines show excellent solubility in polar solvents and strong acids, but they were gradually decomposed in extended contact with moisture. Polyformamidines containing rigid para structures are well crystallizing materials, which was proved by WAXS investigations. Glass transition temperatures in the range of 62 – 163°C were observed for semicrystalline or amorphous polymers. All aromatic polyformamidines are thermally stable in nitrogen up to 300°C. 相似文献
26.
RATIONALE AND OBJECTIVES: The use of gadolinium (Gd)-BOPTA as a magnetic resonance contrast agent for central nervous system disease was studied in a canine brain abscess model. METHODS: A Streptococcus faecalis brain abscess was evaluated in five dogs at 1.5T. Imaging was performed during the late cerebritis stage, at 5 to 7 days after surgery. Magnetic resonance scans were acquired before and at 1, 5, 15, 30, 45, and 60 minutes after contrast administration, using a dose of 0.1 mmol/kg. Scans also were acquired both before and after contrast injection with the implementation of magnetization transfer. RESULTS: Lesion enhancement, quantified by region-of-interest measurement, peaked at 5 minutes after contrast injection. Both the increase in lesion enhancement from 1 to 5 minutes after injection and the decrease from 5 to 15 minutes after injection, although small, were statistically significant (P < 0.004 and P < 0.03, respectively). The application of magnetization transfer improved lesion enhancement, as measured by signal difference/noise, by 39%. This result also was statistically significant (P < 0.001). CONCLUSIONS: In intraparenchymal brain infection, Gd-BOPTA provides effective lesion enhancement when used at a dose of 0.1 mmol/kg. Further research is needed to compare the magnitude of enhancement achieved with Gd-BOPTA, which has weak protein binding and both hepatobiliary and renal excretion, with that with Gd chelates, which have pure renal excretion. 相似文献
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