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51.
基于小波变换的两种惯性传感器数据融合 总被引:3,自引:1,他引:2
针对光电跟踪系统中两种高低不同带宽的惯性传感器,采用小波滤波的方式滤除噪声,并在此基础上,引入小波系数方差作为信号的特征量,构造低频系数的权值,实现两种不同带宽的惯性传感器信号的融合.通过采用提升小波变换,使设计更为灵活、计算简单、速度更快.最后的实验验证了该算法的有效性,从其结果可以看出,在融合的整个频段,除了在频率的交接处(30~40Hz)有轻微的波动外,在别的频段都与真实数据吻合的比较好.在融合的整个频段,幅值最大衰减为-2.5dB,相移最大滞后大约为30o. 相似文献
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Yasmine Ammar Sharon JoyceRosemary Norman Yaodong WangAnthony P. Roskilly 《Applied Energy》2012,89(1):3-20
Thermal energy loss in the process industry is a significant issue due to the high temperatures and multiple heat intensive processes involved. High-grade thermal energy is typically recovered within processes. However, lower grade heat is often rejected to the environment.The benefits of capturing and utilising low grade thermal energy are highly dependent on the qualities and properties of the heat in the waste streams. The temperature of the low grade heat stream is the most important parameter, as the effective use of the residual heat or the efficiency of energy recovery from the low grade heat sources will mainly depend on the temperature difference between the source and a suitable sink, e.g. another process or space heating/cooling. In general, the temperatures of these waste heat sources are too low to produce electricity and direct heat use will depend on whether potential user can be found.This paper presents past and current drivers for heat recovery studies. High and low grade heat sources are defined according to the viability of recovery within the processes. Firstly, high grade heat capture within the processes is reviewed. Then, the focus is on the potential for low grade heat capture outside of the original plant. The paper addresses the potential for low grade heat recovery with regard to new incentives and technological advances. Finally, different aspects which influence the decision making for low grade heat recovery in the process industry are discussed. It is concluded that organisational, financial and economic barriers might be overcome and benefits from a holistic vision could be gained with stronger governmental policy and regulation incentives. 相似文献
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基于苹果采摘的开放性特点,结合苹果采摘的实际操作,提出了机器人采摘的整体结构方案。为实现设计的可应用性,对苹果采摘机器人腰部升降台、机械手臂、末端执行器进行具体的结构设计。 相似文献
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本文在分析了我国工业自动化仪表现状的基础上,提出了我国工业过程测量和控制系统标准体系框架和实施计划。 相似文献
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随着采矿设备的发展,开采量的增加对近年来广泛应用的单轨吊的性能提出了更高的要求。以单轨吊起吊液压回路为研究对象,分析其液压制动缸进油路上的阻尼孔对马达启动的影响。建立系统的数学模型,并在Simulink中仿真得出结果,再通过AMESim进行仿真试验。结果表明:在制动液压缸的进油路上设置阻尼孔对马达的启动具有延时作用,可以让马达有足够大的启动转矩时迅速启动,防止因解除制动过快而马达启动转矩不足的情况出现;相对于无阻尼孔的回路,其液压冲击也会减弱,随着阻尼孔孔径的减小,延时效果会更加明显。 相似文献
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Objective: Interventions are increasingly described as theory-based; however, the basis for this is often not clear. Advancing behavioral science requires a good understanding of how interventions are informed by, and test, theory. This study aims to develop a reliable method for assessing the extent to which behavioral interventions are theory-based. Design: The reliability, usability, and comprehensiveness of an initial coding scheme were improved in 13 iterative stages on the basis of its application to 29 papers, from a systematic review of interventions to promote physical activity and healthy eating. Results: The final Theory Coding Scheme contained 19 items, each with satisfactory interrater reliabilities, coding whether a theory or model was mentioned, how theories were used in intervention design, how intervention evaluations tested theory, and the implications of the results for future theory development. Conclusion: The Theory Coding Scheme is an important methodological innovation, providing a research tool to reliably describe the theoretical base of interventions, inform evidence syntheses within literature reviews and meta-analyses, and stimulate the use of empirical data for theory development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献