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51.
This article documents that the hydrogen economy continues to attract significant attention among politicians, the media, and some academics. We believe that an explanation lies in the way that the hydrogen economy fulfills psychological and cultural needs related to a future world where energy is abundant, cheap, and pollution-free, a “fantasy” that manifests itself with the idea that society can continue to operate without limits imposed by population growth and the destruction of the environment. The article begins by explaining its research methodology consisting of two literature reviews, research interviews of energy experts, and the application of symbolic convergence theory, a general communications theory about the construction of rhetorical fantasies. We then identify a host of socio-technical challenges to explain why the creation of a hydrogen economy would present immense (and possibly intractable) obstacles, an argument supplemented by our research interviews. Next, we employ symbolic convergence theory to identify five prevalent fantasy themes and rhetorical visions—independence, patriotism, progress, democratization, and inevitability—in academic and public discussions in favor of the hydrogen economy. We conclude by offering implications for scholarship relating to energy policy more broadly. 相似文献
52.
Engineering education research has experienced a notable scale‐up in recent years through the development of departments and degree programs, high‐profile publication outlets, research agendas, and meetings. We begin by reviewing these developments, contextualizing them historically, and clarifying some relevant terminology. We then use observational data collected at the 2007 inaugural International Conference on Research in Engineering Education (ICREE) to examine how engineering education is variously conceptualized as a discipline, community of practice, and/or field. We also examine how ICREE participants engaged with questions about the infrastructure and major goals of engineering education research. Our data reveals both an overall lack of clarity and continued sense of ambiguity about the identity and status of engineering education research. We conclude by recommending that participants and stakeholders work to clarify the goals and objectives of engineering education research, especially to inform the continued development of the field's identity and supporting infrastructures. 相似文献
53.
Maureen G. Walsh Brian F. Lantry Brent Boscarino Kelly Bowen Jocelyn Gerlofsma Ted Schaner Richard Back Jennifer Questel A. Garry Smythe Roberta Cap Michael Goehle Bryan Young Marc Chalupnicki James H. Johnson James E. McKenna Jr. 《Journal of Great Lakes research》2010
Hemimysis anomala, a Ponto-Caspian littoral mysid, is an emerging Great Lakes invader that was discovered in Lakes Michigan and Ontario in 2006. Similar to the native mysid Mysis diluviana, Hemimysis exhibits a diel vertical migration pattern but generally inhabits shallower and warmer waters than M. diluviana. Because basic information on the distribution, habitat use, and biology of Hemimysis in the Great Lakes is scarce, the potential for food web disruption by Hemimysis cannot easily be predicted. Preliminary observations indicate widespread invasion of Hemimysis in Lake Ontario. In this study, we confirm the presence of Hemimysis at sites spanning the northern and southern shores of Lake Ontario and the presence of the individuals during winter months. In one horizontal tow in November 2007, over 26,000 individuals were collected with a length range of 4.4 to 9.0 mm and an average caloric density of 611 cal/g wet weight. The most effective methods for sampling Hemimysis were horizontal tows with either a zooplankton net in the water column or a benthic sled near the lake bottom. Although more quantitative data on the life history and distribution of this species is necessary, our preliminary observations support the prediction that the potential for Hemimysis to impact the nearshore food web in Lake Ontario appears high. 相似文献
54.
Memorializes Stephen A. Mitchell, a teacher, administrator and practitioner in psychoanalysis and psychotherapy. Mitchell was a leading proponent of an integrative, relational perspective in psychoanalysis. Mitchell was sympathetic to the plight of psychologists and others excluded from established organizations, and he helped them to establish their own innovative training programs not only in the US but also abroad (e.g., Canada and Israel). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Jun Aihara Shohei Ueta Atsushi Yasuda Hideharu Ishibashi Yasuhiro Mozumi Kazuhiro Sawa Yoshinobu Motohashi 《Journal of the American Ceramic Society》2009,92(1):197-203
The Japan Atomic Energy Agency (JAEA) has started to study and develop zirconium carbide (ZrC)-coated fuel particles for advanced high-temperature gas-cooled reactors. The ZrC coating layer has been fabricated at JAEA by chemical vapor deposition using a pyrolytic reaction of zirconium bromide. The microstructures of the ZrC layers, whose nominal deposition temperatures could be measured and controlled during the deposition process, were characterized by means of TEM and STEM. In the present study, three batches were prepared and compared with each other as well as the previous batches. The crystallographic orientation of ZrC with regard to the growth direction in the ZrC layers deposited at a constant temperature of 1630 K was different from that deposited at varying temperatures in the 1493–1823 K range. A thin layer of turbostratic carbon was observed at the boundary between pyrolytic carbon and ZrC in particles deposited at the highest temperature among those used in this study (the nominal temperature was 1769 K); no such structure was found in a batch deposited at a lower temperature (the nominal temperature was 1632 K). Therefore, precise control of temperature is shown to be critical to the formation of good ZrC coatings. 相似文献
56.
57.
Participants were surveyed after joining a self-help group for unemployed professionals over the age of 40 and again 1 year later. A hidden cost of job loss, especially for older workers, may be decreased satisfaction with the new job obtained after a period of unemployment. Of the 24 initially unemployed participants who sought jobs, 1 year later 16 were reemployed, and 8 were still seeking jobs. The 16 reemployed participants indicated significantly less satisfaction in their new positions, compared to the ones held previously, with regard to pay and benefits. There was no change in satisfaction with co-workers. Satisfaction with supervision, the nature of the work, and prospects for promotion had increased. Positive self-esteem and internal locus of control at the initial survey were positively correlated with job satisfaction after reemployment. Contrary to expectations, age was also positively correlated with satisfaction in the new job. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
An AlGaAs/GaAs HBT direct-coupled amplifier has been designed and its characteristics described for the first time. The amplifier consists of two HBTs and three resistors without level-shift diodes. A superior amplifier performance of 11 dB gain with a 4 GHz bandwidth was obtained. 相似文献
59.
Daniel C. Crues Rajendran K. Raghavan Brent L. Adams 《Metallurgical and Materials Transactions A》1987,18(3):255-264
A self-consistent polycrystalline model developed by Kr?ner, and Budiansky and Wu (KBW) was used to model small strain (2
and 8 × 10-6) biaxial yield behavior in textured copper tubing. The results were compared to simulations using the Bishop-Hill model and
a lower bound (LB) model which neglected strain compatibility. It was found that the Bishop-Hill model poorly represents texture
effects whereas the KBW and LB models give accurate predictions of biaxial yield surfaces at these strain levels. A linear
latent hardening law was used with both the KBW and LB model. Varying the latent hardening ratio an order of magnitude had
little effect on the yield surface. Introducing the odd 1 coefficients of the generalized spherical harmonic expansion was
also found to have negligible effect on the predicted yield loci.
Formerly Graduate Student of Mechanical Engineering at Brigham Young University
Formerly Graduate Student of Materials Science and Engineering at the University of Florida 相似文献
60.
Collected self-report data from 37 pretest clients and 26 of the same clients at posttest who participated in 6 counseling center therapy groups. Questionnaires assessed 6 functionally different types of social support provided from 2 sources, therapy group members vs persons outside the group, together with pre- and posttest levels of 3 distress symptoms, which were depression, self-esteem, and psychological symptoms of stress. Significant improvement in symptoms was noted during the 8-wk interventions, and this improvement was related to the availability of social support, depending on the type and source of support. In general, support from sources outside the therapy group appeared to have the most impact. Levels of certain types of support differed in groups depending on whether or not the group was composed of members with a common presenting concern. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献