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991.
992.
Joseph A. Yesulatitis 《Information Systems Management》1997,14(2):80-82
Leveraging the advantages of outsourcing in the area of new technology adoption depends not only on selecting the right vendor, but on developing a comprehensive strategy that assesses the internal technology environment and meets organizational needs. 相似文献
993.
Z-source inverter for motor drives 总被引:2,自引:0,他引:2
Fang Zheng Peng Joseph A. Jin Wang Miaosen Shen Lihua Chen Zhiguo Pan Ortiz-Rivera E. Yi Huang 《Power Electronics, IEEE Transactions on》2005,20(4):857-863
This paper presents a Z-source inverter system and control for general-purpose motor drives. The Z-source inverter system employs a unique LC network in the dc link and a small capacitor on the ac side of the diode front end. By controlling the shoot-through duty cycle, the Z-source can produce any desired output ac voltage, even greater than the line voltage. As a result, the new Z-source inverter system provides ride-through capability during voltage sags, reduces line harmonics, improves power factor and reliability, and extends output voltage range. Analysis, simulation, and experimental results will be presented to demonstrate these new features. 相似文献
994.
Alan L. Migdall Carsten Winnewisser 《Journal of research of the National Institute of Standards and Technology》1991,96(2):143-146
The effect of optical irradiance on the linearity of a Si photodiode was studied. These results are compared for light modulated at 30 MHz and at dc as the optical irradiance was varied over a 9 decade range. We discuss how these results affect the use of this detector as a heterodyne receiver. As the optical irradiance varied from 10−2 to 10+3 mW/cm2, while maintaining constant total power, the photocurrent was constant to about 1%, but as the power density increased further, the photocurrent increased about 13%. At the highest densities that we could achieve, about 6×107 mW/cm2 there was only slight evidence of the onset of saturation. These results are of importance in our work to use optical heterodyne detection to measure filter transmittances over a wide dynamic range. The results provide guidelines for achieving maximum accuracy when using this particular diode as an optical heterodyne receiver. 相似文献
995.
Céline Poulier David S. Smith Marylène Viana Joseph Absi 《Journal of the American Ceramic Society》2008,91(3):965-969
The thermal response of a ceramic body during firing will be controlled by its thermophysical characteristics. Laser flash measurements have been used to investigate the thermal conductivity of pressed powder compacts of pure tin oxide as a function of temperature. After an initial decrease up to 150°C attributed to removal of surface species, the thermal conductivity increases progressively with thermal treatment up to 1000°C. Because there is almost no variation in the pore volume fraction, the behavior is explained by grain boundary formation and neck growth, which increase the contact area between particles. Supporting evidence is given by an increase in mechanical strength. Finally, thermal treatment above 1000°C increases the thermal conductivity due to a reduction in the number of grain boundaries per unit length of heat path. 相似文献
996.
Phonological competition theory states that competition among discrepant segments of similar words leads to inhibition of high-frequency word-naming responses in form-related priming tasks. If segments are selected sequentially, competition should be greater for begin-related pairs (storage-story), in which discrepant segments are late in the words, than for end-related pairs (glory-story), in which discrepant segments are selected before the shared ones. This pattern was not observed in standard visual priming, probably because of the influence of parallel orthographic input. However, it was observed in a repetitive word-pair production task in which visual input was absent. The findings favor a class of models in which nonsequential activation of phonological content precedes sequential selection of the segments of words to be spoken. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
The interplay of bake oven processing environment and surface/interfacial chemistry, and their effect on intercoat adhesion
has been investigated for a model primer/electrocoat paint system. X-ray photoelectron spectroscopy (XPS) surface analysis
established that a prominent ether component in the C 1s core level spectrum correlated with a polyether-based crater-control
additive in the electrocoat that surface-segregates during cure. Laboratory-simulated bake oven experiments confirmed that
better adhesion characteristics were realized by removal of this electrocoat overlayer through reaction with nitrogen oxides
and high levels of moisture present in the cure environment of production direct-fired ovens. Details of the effect of bake
oven atmosphere on cure chemistry for direct- versus indirect-fired ovens are presented. 相似文献
998.
Challenges in implementing demand side management (DSM) programs in rural electric co-operatives and small municipal utilities are not well understood, yet these organizations sell roughly 15% of electricity in the US, many are more coal-intensive than investor-owned utilities (IOUs), and they are politically important—rural electric co-operatives cover about 75% of the US land area and municipal utilities are found in every state except Hawaii. We provide a background on rural co-operatives and municipal utilities in the context of the US electric sector and highlight the challenges and opportunities of implementing DSM programs in these institutions. Where past studies of utility DSM have mostly focused on IOUs or consisted of qualitative case studies of municipal utilities with exemplary DSM performance, this study makes a unique contribution to the DSM literature by systematically analyzing an entire co-operative and municipal utility population in Minnesota through the use of a survey. In doing so, we provide policy recommendations relevant to energy planners and policy makers to support DSM in rural electric co-operatives and municipal utilities. 相似文献
999.
Utilization of the dead sea minerals (a review) 总被引:1,自引:0,他引:1
Joseph A. Epstein 《Hydrometallurgy》1976,2(1):1-10
1000.
Joseph J. Jaglowski Jr 《Fire Technology》1966,2(4):273-275
How can more people be evacuated from an aircraft in less time than is currently possible? The author discusses a concept that is under study at this time—the concept of blasting additional openings in fuselage walls. 相似文献