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91.
Stuart A. Umpleby 《控制论与系统》2013,44(1):99-108
A task as large as influencing the global economy requires that some thought be given to suitable strategies. Recent work in the science of cybernetics has identified four separate strategies for regulating complex systems composed of thinking participants. By using these strategies as a foundation, this paper reviews the history of the global economy, summarizes current concerns, and then identifies several possible courses of action. 相似文献
92.
Alison Wenham Lihui Song Malcolm Abbott Iskra Zafirovska Sisi Wang Brett Hallam Catherine Chan Allen Barnett Stuart Wenham 《Frontiers in Energy》2017,11(1):60-66
Cast-mono crystalline silicon wafers contain crystallographic defects, which can severely impact the electrical performance of solar cells. This paper demonstrates that applying hydrogenation processes at moderate temperatures to finished screen print cells can passivate dislocation clusters within the cast-mono crystalline silicon wafers far better than the hydrogenation received during standard commercial firing conditions. Efficiency enhancements of up to 2% absolute are demonstrated on wafers with high dislocation densities. The impact of illumination to manipulate the charge state of hydrogen during annealing is investigated and found to not be significant on the wafers used in this study. This finding is contrary to a previous study on similar wafers that concluded increased H– or H0 from laser illumination was responsible for the further passivation of positively charged dangling bonds within the dislocation clusters. 相似文献
93.
Sinico Michele; Parovel Giulia; Casco Clara; Anstis Stuart 《Canadian Metallurgical Quarterly》2009,35(4):948
We show that human observers strongly underestimate a linear or circular trajectory that a luminous spot follows in the dark. At slow speeds, observers are relatively accurate, but, as the speed increases, the size of the path is progressively underestimated, by up to 35%. The underestimation imposes little memory load and does not require tracking of the trajectory. Most importantly, we found that underestimation occurred only when successive motion vectors changed in direction. This suggests a perceptual rather than representational origin of the illusion, related to vector-sum integration over time of neural motion signals in different directions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Strong and lightweight fibre reinforced polymeric composites now dominate the aerospace, marine and low-volume automotive sectors. The surface finish on exterior composite panels is of critical importance for customer satisfaction. This paper describes the application of wavelet texture analysis (WTA) to the task of automatically classifying the surface finish of Carbon Fibre Reinforced Plastic (CFRP) samples into two quality grades. Automatic classification was successful for all but four samples out of 14,400 classification trial configurations, representing 403,200 sample classification attempts (28 attempts per configuration). This work establishes the principle of WTA as a basis for automatic surface finish classification of composite materials. 相似文献
95.
Stuart Jones 《AI & Society》2012,27(2):223-231
The author examines concepts of real time and real-time in relation to notions of perception and processes of sonification.
He explores these relationships in three case studies and suggests that sonification can offer a form of reconciliation between
ontology and phenomenology, and between ourselves and the flux we are part of. 相似文献
96.
97.
Christa D. Jensen Donald J. Lacombe Stuart G. McIntyre 《Papers in Regional Science》2013,92(3):651-666
The Conservative Party won the 2010 General Election in the United Kingdom, gaining the most votes and seats of any single party. Using Bayesian spatial econometric methods, we show that significant spatial dependence exists in Conservative voting behaviour and select the spatial Durbin model as the best model to explain this phenomenon. This paper examines these spatial effects as well as the effects of a range of economic, socio‐economic, and political variables. Perhaps the most interesting result is that incumbency has effects beyond an incumbent's own constituency. 相似文献
98.
Stuart Crozier Ph.D. Stephen Dodd Kurt Luescher James Field David M. Doddrell 《Magma (New York, N.Y.)》1995,3(1):49-55
By extending the formalism previously developed for the design of unshielded, biplanar gradient coils, shielded biplanarB
0 coils optimized for homogeneity and either minimum energy or minimum power may be designed. We present results from an integrated
approach to shielded biplanar coil design, the results of which are also applicable to gradient coils, enabling the design
of shielded coils with a concomitant decrease in total inductance of the coil. Length constraints are also included in the
integrated minimization procedure. Results from a preliminary design indicate that high-homogeneity, low-impedance, well-shielded
coils result from this design approach. 相似文献
99.
Swindells M Rae M Pearce M Moodie S Miller R Leach P 《Philosophical transactions. Series A, Mathematical, physical, and engineering sciences》2002,360(1795):1179-1189
We describe the challenges faced when developing a Linux/PC-based cluster to apply bioinformatics algorithms to the rapidly increasing raw genomics data available. The calculations, which take around two months to complete, result in a powerful resource that can be used for data mining--most obviously for the human genome. Our current infrastructure consists of a 1314 node cluster with 1734 processors supporting both production and research. This paper highlights the problems in achieving high data throughput with such systems and shows that raw computer power is only one component of a complex problem. 相似文献
100.
Evans SA Elliott JM Andrews LM Bartlett PN Doyle PJ Denuault G 《Analytical chemistry》2002,74(6):1322-1326
Mesoporous (H(I)-ePt) platinum microelectrodes electrodeposited from the hexagonal (H(I)) lyotropic liquid crystalline phase are shown to be excellent amperometric sensors for the detection of hydrogen peroxide over a wide range of concentrations. Good reproducibility, high precision, and accuracy of measurements are demonstrated. Mesoporous microelectrodes retain the high rates of mass transport typical of conventional microelectrodes, and their high real surface area greatly enhances their catalytic activity. This unique combination of properties overcomes the limitations of previous amperometric hydrogen peroxide sensors and yields outstanding qualitative and quantitative results. 相似文献