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排序方式: 共有341条查询结果,搜索用时 31 毫秒
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Belcher Calvin H. Zheng Baolong MacDonald Benjamin E. Langlois Eric D. Lehman Benjamin Pearce Charles Delaney Robert Apelian Diran Lavernia Enrique J. Monson Todd C. 《Journal of Materials Science》2022,57(9):5518-5532
Journal of Materials Science - For transformers and inductors to meet the world’s growing demand for electrical power, more efficient soft magnetic materials with high saturation magnetic... 相似文献
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Deffenbacher Jerry L.; Lynch Rebekah S.; Oetting Eugene R.; Kemper Calvin C. 《Canadian Metallurgical Quarterly》1996,43(2):149
High-anger 6–8th graders received cognitive-relaxation coping skills (CRCS), social skills training (SST), or no treatment. Compared to the control, CRCS and SST were equally effective in reducing trait, general, and personal–situational anger and outward negative anger expression, as well as increasing controlled anger expression. On other variables, however, CRCS showed some superiority. Although both interventions led to equivalent reductions on one measure of anxiety, CRCS lowered depression, shyness, general deviance, and another measure of anxiety, whereas SST did not and was not significantly different from other groups. CRCS lowered school deviance more than SST. No between-group differences were found on self-esteem, alcohol consumption, or intoxication. Possible explanations of these findings were discussed, along with methodological issues. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Michal Podhradský Calvin Coopmans Austin Jensen 《Journal of Intelligent and Robotic Systems》2014,74(1-2):193-207
Small unmanned aerial vehicles (UAV) are typically driven by Lithium polymer batteries. The batteries have their own dynamics, which changes during discharge. Classical approaches to altitude control assume a time-invariant system and therefore fail. Adaptive controllers require an identified system model which is often unavailable. Battery dynamics can be characterized and used for a battery model-based controller. This controller is useful in situations when no feedback from actuators (such as RPM or thrust) is available. After measuring the battery dynamics for two distinct types of batteries, a controller is designed and experimentally verified, showing a consistent performance during entire discharge test and a consequent flight verification. 相似文献
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Dong Quan Peter Moloney Declan Carolan Hisham Abourayana Calvin Ralph Alojz Ivankovic Denis Dowling Neal Murphy 《应用聚合物科学杂志》2021,138(1):49605
This work studied the effects of adding short basalt fibers (BFs) and multi-walled carbon nanotubes (MWCNTs), both separately and in combination, on the mechanical properties, fracture toughness, and electrical conductivity of an epoxy polymer. The surfaces of the short BFs were either treated using a silane coupling agent or further functionalized by atmospheric plasma to enhance the adhesion between the BFs and the epoxy. The results of a single fiber fragmentation test demonstrated a significantly improved BF/epoxy adhesion upon applying the plasma treatment to the BFs. This resulted in better mechanical properties and fracture toughness of the composites containing the plasma-activated BFs. The improved BF/epoxy adhesion also affected the hybrid toughening performance of the BFs and MWCNTs. In particular, synergistic toughening effects were observed when the plasma-activated BFs/MWCNTs hybrid modifiers were used, while only additive toughening effects occurred for the silane-sized BFs/MWCNTs hybrid modifiers. This work demonstrated a potential to develop strong, tough, and electrically conductive epoxy composites by adding hybrid BF/MWCNT modifiers. 相似文献
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With the proliferation of macroergonomic field research, it is time to carefully examine how such research should be managed and implemented. We argue that the importance of attending to high-quality implementation of field research is equal to that of methodological rigor. One way to systematically manage the implementation process is to adopt a change management framework, wherein the research project is conceptualized as an instance of organization-level change. Consequently, principles for successful organization-level change from the literature on change management can be used to guide successful field research implementation. This paper briefly reviews that literature, deriving 30 principles of successful change management, covering topics such as political awareness, assembling the change team, generating buy-in, and management support. For each principle, corresponding suggestions for macroergonomic field research practice are presented. We urge other researchers to further develop and adopt frameworks that guide the implementation of field research. 相似文献
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In recent years the incorporation of ZnO as a semiconductor into other catalysts, for enhancing photodegradation processes, has gained attention. This paper describes the synthesis of a blend of metal oxide (TiO2/ZnO) photocatalyst and subsequent testing of the catalyst for the degradation of phenol in an annular photoreactor. The concentration of phenol before and after degradation was determined using Ultra-Violet-Spectroscopy (UV-Vis). Calcined TiO2/ZnO composite material with a mass loading ratio of 1: 1 exhibited the highest percentage phenol removal compared to the unblended TiO2 and ZnO systems at pH 7.2 and temperature of 25°C. It was shown that about 98% phenol degradation could be achieved at initial phenol concentration of 10; 20 and 50 ppm, except for 100 ppm which gave less than 50% degradation. Thus, TiO2/ZnO blend as photocatalyst can be used for degradation of phenol in water. The pseudo-first order reaction kinetics fitted well the Langmuir-Hinshelwood model in almost all concentration ranges tested. 相似文献