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991.
992.
Duncan Johnston Chris Barnardo Chris Fryer 《Journal of the Society for Information Display》2005,13(6):487-491
Abstract— A method is required for creating a graphics display, or pixel array, from printed electroluminescent (PEL) display technology and driving it efficiently and cost effectively. The display is made up of a matrix of capacitive light‐emitting display elements which are to be driven by a passive multiplexing method. A four‐level drive system is required in order to produce the best possible contrast ratio on the display. A four‐level drive system is costly to implement at the high voltages at which PEL displays operate, but a system is presented here which is able to make a significant reduction in the amount of electronics required to control the display. By selectively switching the output from a fly‐back power supply to different parts of the matrix display, the optimum voltages can be obtained across all segments from a single high‐voltage power supply. This provides potential for using passive‐matrix PEL displays in a wide variety of applications, as well as having possible applications for other display technologies such as PDLCs (see demonstration in Fig. 1). 相似文献
993.
The Stern Review received widespread attention for its innovative approach to the economics of climate change when it appeared in 2006, and generated controversies that have continued to this day. One key controversy concerns the magnitude of the expected impacts of climate change. Stern's estimates, based on results from the PAGE2002 model, sounded substantially greater than those produced by many other models, leading several critics to suggest that Stern had inflated his damage figures. 相似文献
994.
有一位智者曾经说过:“预测未来实际上是一门如何合理看待现在的艺术”。对于整个移动行业来说,2009年,由于严重的金融危机,毫无疑问将是非常艰苦的一年。但是,移动短信息业务的发展不在此例。 相似文献
995.
Burns G. Leonard; de Moura Marcela Alves; Walsh James A.; Desmul Chris; Silpakit Chatchawan; Sommers-Flanagan John 《Canadian Metallurgical Quarterly》2008,20(2):121
Confirmatory factor analysis was used to test the invariance of an oppositional defiant disorder toward adults, attention-deficit/hyperactivity disorder-hyperactivity/impulsivity, attention-deficit/hyperactivity disorder-inattention, and an Academic Competence factor model between mothers' and fathers' ratings within Brazilian (n = 894), Thai (n = 2,075), and American (n = 817) children with the Child and Adolescent Disruptive Behavior Inventory (G. L. Burns, T. Taylor, & J. Rusby, 2001a, 2001b). The results showed invariance of item loadings, intercepts, and residuals, as well as factor variances, covariances, and means between mothers' and fathers' ratings within each sample. Convergent and discriminant validity was also observed for the between-parent factor correlations, thus providing additional support for the construct validity of the Child and Adolescent Disruptive Behavior Inventory. The confirmatory factor analysis invariance procedure provides a much better way to examine between-source ratings of behavior problems in children than do the simple correlation and raw discrepancy score procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
Gholamreza Mirshekari Ryan Ouimet Zhiqiao Zeng Haoran Yu Stoyan Bliznakov Leonard Bonville Allison Niedzwiecki Chris Capuano Katherine Ayers Radenka Maric 《International Journal of Hydrogen Energy》2021,46(2):1526-1539
Improved activity and durability performance of a two-cell (86 cm2) proton exchange membrane water electrolyzer (PEMWE) stack is reported for the first time. Both membrane electrode assemblies (MEAs) contain one order of magnitude lower platinum group metal (PGM) loadings compared to the state-of-the-art PEMWEs and incorporate novel Pt recombination layers. The high-performance and cost-effective MEAs are fabricated by the unique reactive spray deposition technology (RSDT). This advanced methodology allows for one-step fabrication of MEAs and ensures precise control and distribution of the catalyst composition and loading. The RSDT-fabricated MEAs contain only 0.2 and 0.3 mgPGM cm?2 loading in the cathode and anode electrodes, respectively, and demonstrate excellent activity and durability for over 3000 h of operation at industrially-relevant operating conditions without showing significant loss in performance. This novel work shows that a significant cost reduction for PEMWEs is achieved while maintaining excellent durability, high catalysts activities, and low hydrogen cross-over. 相似文献
997.
Nazmus SAKIB Xuxue SUN Nan KONG Chris MASTERSON Hongdao MENG Kelly SMITH Mingyang LI 《工程管理前沿(英文版)》2022,9(4):577
Post-acute care (PAC) residents in nursing homes (NHs) are recently hospitalized patients with medically complex diagnoses, ranging from severe orthopedic injuries to cardiovascular diseases. A major role of NHs is to maximize restoration of PAC residents during their NH stays with desirable discharge outcomes, such as higher community discharge likelihood and lower re/hospitalization risk. Accurate prediction of the PAC residents’ length-of-stay (LOS) with multiple discharge dispositions (e.g., community discharge and re/hospitalization) will allow NH management groups to stratify NH residents based on their individualized risk in realizing personalized and resident-centered NH care delivery. Due to the highly heterogeneous health conditions of PAC residents and their multiple types of correlated discharge dispositions, developing an accurate prediction model becomes challenging. Existing predictive analytics methods, such as distribution-/regression-based methods and machine learning methods, either fail to incorporate varied individual characteristics comprehensively or ignore multiple discharge dispositions. In this work, a data-driven predictive analytics approach is considered to jointly predict the individualized re/hospitalization risk and community discharge likelihood over time in the presence of varied residents’ characteristics. A sampling algorithm is further developed to generate accurate predictive samples for a heterogeneous population of PAC residents in an NH and facilitate facility-level performance evaluation. A real case study using large-scale NH data is provided to demonstrate the superior prediction performance of the proposed work at individual and facility levels through comprehensive comparison with a large number of existing prediction methods as benchmarks. The developed analytics tools will allow NH management groups to identify the most at-risk residents by providing them with more proactive and focused care to improve resident outcomes. 相似文献
998.
Sulphur‐dyed cellulosic textiles are susceptible to washing powders containing activated peracid formulations resulting in obvious fading during repeated laundering. This study presents a novel one‐bath/two‐stage exhaust finishing process to improve the oxidative wash fastness of CI Leuco Sulphur Black 1‐dyed cotton fabric. The effect of the combined Tinofix ECO and Bayprotect Cl after‐treatment was to impart better colour fastness to oxidative International Organisation for Standardisation (ISO) 105 CO9 washing of the dyed cotton compared with those dyed fabrics after‐treated with Tinofix ECO alone. In addition, while the dyed fabrics rub and light fastness performances were unchanged by the after‐treatments, some improvement in the tensile strength of the combined Tinofix ECO and Bayprotect Cl after‐treated fabrics was observed. 相似文献
999.
1000.
Ning Xiang Xiaowen Zhang Mengyao Zheng Yong Ge Tao Wang Haibao Liu Chris Maharaj John P. Dear Yue Yan 《应用聚合物科学杂志》2020,137(29):48891
The use of injection molding technology to prepare heterogeneous interlayer film of laminated glass holds strong applicable potential. This article aims to investigate the effects of melt temperature and melt flow on the microstructure evolution and tensile properties of thermoplastic polyurethane (TPU) specimens during the injection molding process. The tensile properties of the TPU specimens show dependency on the melt temperature and melt flow direction. The results of birefringence indicate that melt flow and lower melt temperature induce higher stretching deformation of the molecular chain network. Small-angle X-ray scattering analysis approves that besides the melt temperature and flow direction, the testing position on the cross section of the specimen has great influence on the microstructure of the TPU sheet. Further analysis and conclusions can be made using wide-angle X-ray scattering method. The above results demonstrate that both the tensile properties and microstructure of the injection molded TPU specimens tend to be isotropic with the increase of melt temperature. © 2020 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48891. 相似文献