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141.
Rebecca Jones‐Albertus David Feldman Ran Fu Kelsey Horowitz Michael Woodhouse 《Progress in Photovoltaics: Research and Applications》2016,24(9):1272-1283
To quantify the potential value of technological advances to the photovoltaics (PV) sector, this paper examines the impact of changes to key PV module and system parameters on the levelized cost of energy (LCOE). The parameters selected include module manufacturing cost, efficiency, degradation rate, and service lifetime. NREL's System Advisor Model (SAM) is used to calculate the lifecycle cost per kilowatt‐hour (kWh) for residential, commercial, and utility scale PV systems within the contiguous United States, with a focus on utility scale. Different technological pathways are illustrated that may achieve the Department of Energy's SunShot goal of PV electricity that is at grid price parity with conventional electricity sources. In addition, the impacts on the 2015 baseline LCOE due to changes to each parameter are shown. These results may be used to identify research directions with the greatest potential to impact the cost of PV electricity. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Linear potentiometers and approximation circuits have been employed in a simple and inexpensive device which accurately reproduces the contour of a patient to within ±2 mm. Reliable measurement of patient contours is necessary for accurate dosimetry in radiation therapy treatments. 相似文献
145.
Some U.S. hospitals double-load x-ray cassettes for certain procedures. Loading two films in the same cassette for portable emergency room (ER), intensive care unit (ICU), or operating room radiographs provides both the referring clinicians and the radiologists with immediate images. Our study demonstrates a cost increase of 15%, an increase in air kerma for a chest x ray from 0.12 to 0.35 mGy (12-35 mrad), slight differences in optical density, image contrast, and spatial resolution under double-loading conditions. Our study shows that double loading cassettes may improve patient care by economically expediting the communication of radiographic findings. The decision to double load portable ICU or ER cassettes must be based on a balance of factors. 相似文献
146.
Michelle A.Kelsey 《中国电子商情》2007,(10)
近接传感器及加速器正在改变着玩家的游戏体验。尽管这些技术不是新技术,但它们在用户接受程度、规模、性能和价格上的改进正迅速推动着其在游戏市场的广泛应用。 相似文献
147.
G. Joseph J. C. Miller R. E. Berry J. Wernz A. F. Moldenke R. G. Kelsey 《Journal of chemical ecology》1991,17(9):1783-1799
Individual families of gypsy moth collected from a single population exhibited different degrees of fitness when fed diets of white alder, a suitable broadleaf host, and Douglas-fir, an unsuitable conifer host. Members of families on diets of Douglas-fir had significantly lower survival, longer larval periods, lower pupal weights, and shorter pupal periods than members of the same families fed alder. Foliar nutritional quality, including nitrogen level and allelochemical composition (terpenes and phenols), was considered the key factor responsible for these differences. Growth parameters differed significantly for families within diet treatments, indicating that the genetic resources of a family did affect performance somewhat. The influence of a family's genetic resources on larval survival was most notable when larvae were under the greatest nutritional stress. 相似文献
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Rats with lesions of the medial septum were more likely to begin swimming in the wrong direction, swim farther, and, therefore, require more time to find a platform hidden in a Morris water tank than were control rats. Although the performance of the rats with medial septal lesions did improve over trials, their asymptotic performance also failed to equal that of the controls. Movement of the platform to a new position in the tank disrupted the performance of both groups, and, again, the rats with medial septal lesions were slower to locate the moved platform. However, this deficit was completely eliminated when a visual cue indicating the location of the moved platform was introduced. We suggest that these data indicate that damage to the septo-hippocampal cholinergic projection system produces a deficit in the formation or utilization of a spatial map (reference memory) that represents the location of a place with respect to the surrounding distal cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
150.
Matthews Karen A.; Wing Rena R.; Kuller Lewis H.; Meilahn Elaine N.; Kelsey Sheryl F.; Costello E. Jane; Caggiula Arlene W. 《Canadian Metallurgical Quarterly》1990,58(3):345
We investigated the psychological and symptom consequences of the natural menopause in a longitudinal study of 541 initially premenopausal healthy women. All women were given an extensive evaluation at baseline. After 3 yrs of follow-up, 69 women ceased cycling for 12 months; another 32 women had ceased cycling and had taken hormone replacement therapy for a total of 12 months. These women were reevaluated in a clinic examination identical with the baseline examination, as were 101 age-matched premenopausal control women. Comparison among groups at the baseline and follow-up examination showed that natural menopause led to few changes in psychological characteristics, with only a decline in introspectiveness and an increase in reports of hot flashes being apparent. We conclude that natural menopause did not have negative mental health consequences for the majority of middle-aged healthy women. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献