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261.
Implant Materials: Assessment of Novel Long‐Lasting Ceria‐Stabilized Zirconia‐Based Ceramics with Different Surface Topographies as Implant Materials (Adv. Funct. Mater. 40/2017) 下载免费PDF全文
262.
263.
Sanna-Mari Kuoppamäki Sakari Taipale Terhi-Anna Wilska 《Telematics and Informatics》2017,34(4):110-117
Older adults are becoming an important market segment for all internet-based services, but few studies to date have considered older adults as online shoppers and users of entertainment media. Utilising the concept of life course, this article investigates the use of mobile technologies for online shopping and entertainment among consumers aged 55 to 74. The data were collected with a web-based survey completed by a panel of respondents representing Finnish television viewers (N = 322). The results reveal that consumers aged 55 to 74 use a smartphone or tablet to purchase products or services online as often as younger consumers. In contrast, listening to internet radio and watching videos or programmes online with a smartphone or tablet are most typical for younger male consumers. The results demonstrate that mobile-based online shopping is best predicted by age, higher education, and household type (children living at home), and use of entertainment media by age and gender. 相似文献
264.
Heinz E. May T. Born D. Zieger G. Anders S. Zakosarenko V. Meyer H.-G. Schäffel C. 《Journal of Infrared, Millimeter and Terahertz Waves》2015,36(10):879-895
Journal of Infrared, Millimeter, and Terahertz Waves - Passive submillimeter-wave imaging is a concept that has been in the focus of interest as a promising technology for personal security... 相似文献
265.
266.
Daniel Svärd Christer Jansson Atila Alvandpour 《Analog Integrated Circuits and Signal Processing》2013,77(1):29-44
This paper describes a readout integrated circuit architecture for an infrared focal plane array intended for infrared network-attached video cameras in surveillance applications. The focal plane array consists of 352 × 288 uncooled thin-film microbolometer detectors with a pitch of 25 μm, enabling ambient temperature operation. The circuit features a low-noise readout path, detector resistance mismatch correction and a non-linear ramped current pulse scheme for the electrical biasing of the detectors in order to relax the dynamic range requirement of amplifiers and the ADC in the readout channel, imposed by detector process variation and self-heating during readout. The design is implemented in a 0.35-μm standard CMOS process and two versions of a smaller 32 × 32-pixel test chip have been fabricated and measured for evaluation. The latest test chip achieves a dynamic range of 97 dB and an input-referred RMS noise voltage of 6.4 μV yielding an estimated NETD value of 26 mK with f/1 optics. At a frame rate of 60 FPS the chip dissipates 170 mW of power from a 3.4 V supply. 相似文献
267.
T. K. Tran A. Parikh S. D. Pearson B. K. Wagner R. G. Benz R. N. Bicknell-Tassius C. J. Summers T. Kelz J. W. Tomm W. Hoerstel P. Schäfer U. Muller 《Journal of Electronic Materials》1996,25(8):1203-1208
We present a study of the electro-optical properties ofHg
1- xCdxTe epitaxial layers and Hg1-x CdxTe/CdTe (0.28 < x < 0.30) superlattice structures by x-ray diffraction, lateral transport and photo- and magneto-luminescence
measurements. Systematic studies of the excitation intensity and magnetic field dependence of the photoluminescence revealed
direct evidence of an excitonic contribution to the observed luminescence in Hg1- xCdxTe epitaxial layers. Similar investigations of the superlattice structures indicated that excitonic corrections were required
to adequately fit the luminescence data. Optical gains of 80 cm−1 were obtained for an excitation intensity of 100 kW/cm2 indicating suitable electro-optical properties for making efficient mid-infrared laser diodes. 相似文献
268.
Juha Häkkinen Timo Rahkonen Juha Kostamovaara 《Analog Integrated Circuits and Signal Processing》1998,15(1):71-83
Two integrated direct I/Q modulators suitable for directupconversion with an output frequency of 950 MHz and baseband frequencies of60 to 500 kHz are fabricated in a 1.2 µm and 0.8 µm BiCMOSprocess, respectively, and their performance under various operatingconditions is discussed. The modulators use different phase shiftertopologies, one of which is based on digital CML latches and the other ondifferential pairs with resistive and capacitive emitter degeneration. Bothcircuits are operated using a single 5 V supply and they consume 50 mA or115 mA depending on the topology. The main properties of the CML modulatorare, for example, an output power of –11 ± 0.5 dBm at 100 MHzand –15 ± 2.25 dBm at 950 MHz over the temperature range of–10 to +85°C, LO suppression of 38 dBc and image rejection of41 dBc. 相似文献
269.
Elvi Räisänen-Ruotsalainen Timo Rahkonen Juha Kostamovaara 《Analog Integrated Circuits and Signal Processing》1998,15(1):49-57
The main features of two time-to-digital convertersbased on interpolation are presented, together with some measurementresults. The first converter is based on digital delay line interpolatorsand has been implemented in a 1.2 µm CMOS process.It has a single-shot resolution of 1 ns (-value)and a nonlinearity less than ±50 ps in the measurementrange 5 to 500 ns. The power consumption of the circuit is 15mW. The second time digitizer has analog interpolators basedon time-to-voltage conversion and has been implemented in a 1.2 µm BiCMOS process. It has a single-shot resolutionof 50 ps and a nonlinearity less than 150 ps in the measurementrange 1 to 300 ns. The power consumption of this circuit is 200mW. 相似文献
270.
Ohne Zusammenfassung 相似文献