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51.
David Sherman 《Cryptologia》2017,41(3):195-238
In addition to being one of the founders of modern American cryptology, William Friedman was a noted cryptologic historian who amassed a major collection of cryptologic literature and artifacts in both his personal and official files. Drawing on over 50,000 pages of documents newly released by the National Security Agency and other sources, this article places the man, his career, and his collections in the context of the government's changing secrecy policies of the early Cold War to offer new insights into Friedman's sometimes fraught relationship with that agency, its efforts to influence the amount and nature of cryptologic information in the public domain, and a series of confrontations over his personal and private papers. 相似文献
52.
Leo MacDonald Ann Sherman 《Canadian Journal of Science, Mathematics, & Technology Education》2013,13(2-3):133-147
Abstract The focus of this paper is an examination of mentorship relationships developed as a result of six students’ participation in a local community science centre sponsored through an NSERC/CRYSTAL project. Each year, a number of students participate in after‐school activities sponsored by the community science centre. Much of this work involves a one‐to‐one approach, with a middle years or high school student working with a professor partner. The professor acts as a mentor to the student, facilitating learning in a manner not always feasible within a school setting with large class sizes. For some students this research may be the basis of a science fair project; for others if is simply a study based on individual interest. Mentored students were interviewed about the nature of that mentorship, with the goal of describing the experience from the students’ perspective. Questions focused on the student's experience of working with a mentor, including how the mentorship relationship was formed, what the importance of the voluntary nature of mentoring was, what the benefits and challenges of working with a mentor were, how the mentorship relationship affected the level of content knowledge the student gained, and what effect the mentoring relationship had on the student's continuing interest in science. The mentorship program offers students the opportunity to work within a developing community of practice. 相似文献
53.
54.
The Density of States and the Transport Effective Mass in a Highly Oriented Semiconducting Polymer: Electronic Delocalization in 1D 下载免费PDF全文
55.
Sherman Jeffrey W.; Kruschke John K.; Sherman Steven J.; Percy Elise J.; Petrocelli John V.; Conrey Frederica R. 《Canadian Metallurgical Quarterly》2009,96(2):305
Stereotype formation may be based on the exaggeration of real group differences (category accentuation) or the misperception of group differences that do not exist (illusory correlation). This research sought to account for both phenomena with J. K. Kruschke's (1996, 2001, 2003) attention theory of category learning. According to the model, the features of majority groups are learned earlier than the features of minority groups. In turn, the features that become associated with a minority are those that most distinguish it from the majority. This second process is driven by an attention-shifting mechanism that directs attention toward group-attribute pairings that facilitate differentiation of the two groups and may lead to the formation of stronger minority stereotypes. Five experiments supported this model as a common account for category accentuation and distinctiveness-based illusory correlation. Implications for the natures of stereotype formation, illusory correlation, and impression formation are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
57.
Jessica J. Sherman Brent A. Murry Daelyn A. Woolnough David T. Zanatta Donald G. Uzarski 《Journal of Great Lakes research》2013
Populations of native unionids have been in steady decline over the past century. The invasion of dreissenid mussels (Dreissena polymorpha and Dreissena rostriformis bugensis) in the mid-1980's impacted already imperiled unionid populations by greatly increasing their regional extinction rates. A selection of Great Lakes coastal wetlands around Michigan was surveyed to locate remnant populations of native unionids. Physical and chemical parameters were measured in coastal wetlands to evaluate the importance of these habitat parameters to remnant unionid assemblages. We assessed fouling rates by dreissenids on unionids and used artificial substrates to estimate dreissenid colonization densities. Live unionids were found in coastal wetlands of the Les Cheneaux Islands, the Lake St. Clair delta, and North Maumee Bay with significantly higher unionid fouling in the Les Cheneaux Islands compared to the other two sampling areas (F2,76 = 4.97, p = 0.0095). No live unionids were documented in Beaver Island, Garden Island, Grand Traverse Bay, or Saginaw Bay wetlands. Dreissena colonization densities on artificial substrates averaged 19,213 m− 2 at one site in North Maumee Bay, and 10,425 m− 2 in Saginaw Bay, but no colonization occurred in the wetlands of Beaver Island, Garden Island, the Les Cheneaux Islands, or Grand Traverse Bay while Dreissena presence in the open water of these regions was evident. Dreissena colonization densities on artificial substrates increased with measures of anthropogenic disturbance and decreased with higher water level fluctuations and aerial exposure. Specific conductance, turbidity, and magnitude of water level fluctuations were important predictors of Dreissena colonization on artificial substrates. 相似文献
58.
Kim Heejung S.; Sherman David K.; Taylor Shelley E. 《Canadian Metallurgical Quarterly》2009,64(6):564b
Responds to R. E. Erard's comments (see record 2009-13007-011) on the current authors' original article (see record 2008-12151-002) which reviewed a number of studies that identified cultural differences in the use and effect of different types of social support among Asians and Asian Americans and European Americans. Essentially, in his comment, Erard denied the validity of research examining cultural differences. The authors strongly believe that the issues concerning within-culture variation do not nullify the importance of conducting research on culturally based psychological and behavioral patterns. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
S. I. Sherman 《Journal of Mining Science》2009,45(5):438-451
The paper describes the research of fault activation in terms of the Central Asia area, analyzes the time and spatial regularities
of this process and probable disturbers for metastability of the fault-and-block crust medium in real time as well as the
potential influence of the disturbance sources on the stability of rock masses under mining. 相似文献
60.
Tracy Jessica L.; Robins Richard W.; Sherman Jeffrey W. 《Canadian Metallurgical Quarterly》2009,96(6):1206
The present research surveyed a group of editors and editorial board members of personality and social psychology journals to examine the practice of psychological science in their field. Findings demonstrate that (a) although personality and social researchers tend to use many of the same approaches, methods, and procedures, they nonetheless show average differences in each of these domains, as well as in their overarching theoretical aims and perspectives; (b) these average differences largely conform to social and personality researchers’ stereotypes about each subgroup; (c) despite their methodological and philosophical differences, the 2 subgroups study many of the same research topics; and (d) the structure of social–personality research practices can be characterized as having 2 independent factors, which closely correspond to L. J. Cronbach’s (1957) correlational and experimental “streams of research.” (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献