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排序方式: 共有577条查询结果,搜索用时 68 毫秒
1.
Journal of Scheduling - 相似文献
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Neda Stoehr Benjamin Baudrit Edmund Haberstroh Michael Nase Peter Heidemeyer Martin Bastian 《应用聚合物科学杂志》2014,131(12)
The objectives of the presented work were to investigate films based on polylactic acid (PLA) and polyethylene glycol (PEG) in order to improve ductility and weldability of PLA films. The effect of plasticizer amount on the thermal, rheological, and mechanical properties of PLA plasticized films was investigated. The PEG content does affect the glass transition and the cold crystallization temperature of PLA in blends, while the melting temperature was not affected by the addition of PEG. The complex viscosity of the neat PLA granules and of plasticized films showed strong temperature and angular velocity dependence. The Young's modulus and tensile strength of plasticized films were improved with increasing plasticizer concentration, while the elongation at break stays rather constant. Plasticized PLA films were furthermore heat welded. These investigations showed that plasticized PLA films can be welded by heat welding. The obtained weld strength is strongly depending on the PEG amount as well as on selected welding parameters. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40394. 相似文献
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Edmund Suckow 《电子与电脑》2011,(10):34-36
医疗产业渴望拥有更多的功能和互操作性,当然还需要无线接口,本文将探讨无线发展趋势及其挑战,包括在采用无线模块时,现在设计中的标准和频率以及功率考虑事项。单节可充电电池的应用将会是通用终端应用的产品, 相似文献
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R. Mahesh A. P. Vinod Edmund M-K. Lai Amos Omondi 《Journal of Signal Processing Systems》2011,62(2):157-171
The ability to support multiple channels of different communication standards, in the available bandwidth, is of importance
in modern software defined radio (SDR) receivers. An SDR receiver typically employs a channelizer to extract multiple narrowband
channels from the received wideband signal using digital filter banks. Since the filter bank channelizer is placed immediately
after the analog-to-digital converter (ADC), it must operate at the highest sampling rate in the digital front-end of the
receiver. Therefore, computationally efficient low complexity architectures are required for the implementation of the channelizer.
The compatibility of the filter bank with different communication standards requires dynamic reconfigurability. The design
and realization of dynamically reconfigurable, low complexity filter banks for SDR receivers is a challenging task. This paper
reviews some of the existing digital filter bank designs and investigates the potential of these filter banks for channelization
in multi-standard SDR receivers. We also review two low complexity, reconfigurable filter bank architectures for SDR channelizers
based respectively on the frequency response masking technique and a novel coefficient decimation technique, proposed by us
recently. These filter bank architectures outperform existing ones in terms of both dynamic reconfigurability and complexity. 相似文献
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This paper addresses issues that relate to downscaling the height of centrifugal fans for application in low profile technologies, such as the cooling of portable power electronics. The parameters studied include flow rate, pressure rise, and power consumption characteristics. The former two of these are measured using a fan characterization rig and the latter by directly measuring the power supplied to the fan. These are studied for fan diameters ranging from 15 to 30 mm with numerous profile heights between 0.3 mm and 15 mm. It is found that all of the phenomena encountered are best described in terms of fan aspect ratio. The results show that the conventional scaling laws cannot be accurately applied when blade profile alone is scaled. Indeed, the only parameter reasonably well predicted was the pressure rise attainable, but that was only accurate for fan aspect ratios greater than 0.17. Below this, the pressure rise generated reduces logarithmically toward zero. The study also reveals that no advantage is gained by using fans of aspect ratio greater than 0.3, as the maximum flow rate attainable decreases slightly above this. Overall, the scaling phenomena reported herein provide invaluable information for the future design of efficient low-profile cooling solutions that are to incorporate such fans. 相似文献
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Edmund C. Penning‐Rowsell 《Landscape Research》2013,38(2):35-37
The paper reports the continuing use of landscape evaluation techniques by local planning departments in England and Scotland. A survey of 165 authorities, with a 67% response rate, shows that 22% percent have used such techniques in the last 5 years, yet their research base remains inadequate. The main reason reported for others not using these methods is lack of need, not antipathy towards the landscape evaluation approach. 相似文献