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21.
Mats L. Cain J.T. Mickle M.H. 《Automation Science and Engineering, IEEE Transactions on》2009,6(1):4-8
In this paper, an indirect noninvasive method for measuring input impedance and the variations in the assembly of the interconnect and packaging between antenna and the integrated circuit (IC) effects of passive radio frequency identification (RFID) transponder (tags) antennas is presented. The analysis of different RFID tags is presented together with the experimental data. 相似文献
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Holahan Charles J.; Moos Rudolf H.; Holahan Carole K.; Brennan Penny L.; Schutte Kathleen K. 《Canadian Metallurgical Quarterly》2005,73(4):658
This study examined (a) the role of avoidance coping in prospectively generating both chronic and acute life stressors and (b) the stress-generating role of avoidance coping as a prospective link to future depressive symptoms. Participants were 1,211 late-middle-aged individuals (500 women and 711 men) assessed 3 times over a 10-year period. As predicted, baseline avoidance coping was prospectively associated with both more chronic and more acute life stressors 4 years later. Furthermore, as predicted, these intervening life stressors linked baseline avoidance coping and depressive symptoms 10 years later, controlling for the influence of initial depressive symptoms. These findings broaden knowledge about the stress-generation process and elucidate a key mechanism through which avoidance coping is linked to depressive symptoms. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Brennan RB 《Applied ergonomics》1987,18(2):95-102
A comparison of two different styles of operator position in a trencher were compared using biomechanical principles and a field survey. A major postural difference between the two styles is the amount of time spent by the operators looking to the rear of their seated position. This was confirmed by a simple experiment. The style of position used in the skid steer type of trencher, facing the working tool, was found to be significantly better than the traditional fore-aft tractor style configuration. 相似文献
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Numerical calculations are presented of the electron and hole ionization rates in GaAs/AlGaAs multiquantum-well APDs (avalanche photodiodes) as a function of the applied electric field and the spatial geometries, i.e., the barrier- and well-layer widths, respectively. The model is calibrated to existing experimental data on bulk GaAs materials and then extrapolated to the multiquantum well structure. It is found that at high electric field strengths the net ionization rate approaches the weighted average of the constituent bulk rates; the potential discontinuity is relatively insignificant. The potential discontinuity most greatly affects the electron ionization rate at low applied electric field strengths within a spatially symmetric structure. It is further determined that the electron-to-hole ionization rate ratio is greatest at low applied electric fields with a spatially symmetric structure with equal well and barrier widths 相似文献
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Nonthermal plasma for pesticide and microbial elimination on fruits and vegetables: an overview 下载免费PDF全文
Khanh Thi Kim Phan Huan Tai Phan Charles S. Brennan Yuthana Phimolsiripol 《International Journal of Food Science & Technology》2017,52(10):2127-2137
Nonthermal plasma (NTP) is defined in terms of partly ionised gas which overall temperature is quite low because the stored energy is mostly in free electrons. Applications of NTP have been expanded to new areas of food applications such as the microbial inactivation and also the elimination of pesticide and toxic chemical residues in food such as fruits and vegetables while nutritional content and key characteristics are still preserved. Plasma treatment has successfully decreased the concentrations of pesticides by about 45‐71%. In this article, NTP technologies as well as investigations about applying of NTP for removing pesticide residues and improving microbial safety in fresh produce are described. Potential applications of NTP in food processing together with some of their challenges and limitations are also discussed. 相似文献
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C. A. Mullen T. J. Vaughan M. C. Voisin M. A. Brennan P. Layrolle L. M. McNamara 《Journal of the Royal Society Interface》2014,11(101)
Extracellular mechanical cues have been shown to have a profound effect on osteogenic cell behaviour. However, it is not known precisely how these cues alter intracellular mechanics to initiate changes in cell behaviour. In this study, a combination of in vitro culture of MC3T3-E1 cells and finite-element modelling was used to investigate the effects of passive differences in substrate stiffness on intracellular mechanics. Cells on collagen-based substrates were classified based on the presence of cell processes and the dimensions of various cellular features were quantified. Focal adhesion (FA) density was quantified from immunohistochemical staining, while cell and substrate stiffnesses were measured using a live-cell atomic force microscope. Computational models of cell morphologies were developed using an applied contraction of the cell body to simulate active cell contraction. The results showed that FA density is directly related to cell morphology, while the effect of substrate stiffness on internal cell tension was modulated by both cell morphology and FA density, as investigated by varying the number of adhesion sites present in each morphological model. We propose that the cells desire to achieve a homeostatic stress state may play a role in osteogenic cell differentiation in response to extracellular mechanical cues. 相似文献
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