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1.
This paper examines the concept of textbook eminence and asks whether this specific form of scholarly recognition is of a temporal rather than enduring nature. Based on an analysis of 30 leading textbooks in economics, psychology and economics from the 1970s and 2010s, it is established that less than a third of all eminent scholars remain across the period as the most cited authors. Therefore, the average “half-life” of textbook eminence is shorter than half a century. Textbook eminence, it seems, is associated first and foremost with ‘certified recognition,’ expressed through encyclopedia entries dedicated to individual scholars. In psychology, and partly in sociology, citation impact turns out to be a further significant correlate. In economics, however, textbook eminence is completely detached from peer recognition, as measured by the h-index. The identified short “half-life” of textbook eminence does not necessarily imply a replacement of older elites by younger researchers. In sociology, very few 20th century newcomers have yet attained textbook eminence.  相似文献   

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《Composites Part A》2001,32(10):1395-1414
The forming of fibre fabric reinforcements without a matrix is possible because of their very specific mechanical behaviour. The lack of some rigidities is due to possible motions between the fibres. For the fabrics used as reinforcement in the R.T.M. process and composed of warp and weft yarns made with untwisted fibres, the tension stiffness is very preponderant compared to the others. The tensile behaviour of such a fabric is biaxial, i.e. the tension-deformation states in warp or weft directions depend on the other direction because of the interweaving. It is given by the knowledge of two surfaces relating the warp and weft tensions to the two strains in these directions (or that of a single surface if the fabric is balanced). In the present paper, three complementary methods are investigated in order to determine these surfaces. A biaxial tensile device on a cross-shaped specimen is first used. 3D finite element simulations of the unit woven cell are then presented. This mesoscopic study permits to understand some phenomena at the elementary woven cell level. Finally a simplified model, which is consistent with the geometry of the plain weave woven mesh is presented. The agreement of the two last methods with experimental results is shown. From these tensile behaviour surfaces, a dynamic explicit approach for the simulations of a fabric sheet forming process is presented. The interests of the method are both its good numerical efficiency, particularly due to the direct use of the biaxial tension surfaces, and its proximity with fabric physics.  相似文献   

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In the decades after World War I, the development of aviation and meteorology became increasingly entangled, with the result that meteorology became a necessary part of the epistemic infrastructure of routine aviation. This paper explores the complex re-spatialisation of meteorological practice that occurred as the New Zealand Meteorological Service (NZMS) transformed its data collection, interpretation, and forecasting services to support New Zealand's aspirations for aviation prior to the Second World War. Crucial to this work was the transformation of meteorology's spatialities to incorporate a volumetric understanding of the upper atmosphere's turbulent dynamics. Making meteorology three-dimensional required profound conceptual and practical work to fashion new spaces of concern. This meant developing instruments and practices through which phenomena, such as high-altitude winds, could be recorded, mapped, and communicated. However, this spatial transformation was also simultaneously a temporal transformation framed by the demands of becoming infrastructural. New Zealand's meteorologists lobbied the government for the resources to synchronise atmospheric dynamism with the demands for increasingly quick and fine-grained forecasts. Making the atmosphere three-dimensional profoundly changed meteorology, but meteorology in New Zealand was only able to become infrastructural to the extent that it was able to integrate, and strategically mobilise, new forms of temporality into its emerging spaces of concern.  相似文献   

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With increasing recognition of failed water and sanitation projects in developing countries, it has become apparent that appropriate technology is often insufficient to create lasting water infrastructure. Specifically, low sustainability of household Arsenic–Iron Removal Plants (AIRPs) in rural areas of Bangladesh is examined. In the village studied, less than 40 of 135 AIRPs, installed three years ago, are being used and maintained regularly. Further, performance of those still being used has decreased by 10% in terms of arsenic removal. Discussion with village residents and with the implementing NGO indicated that the most common reasons for discontinued use of the units was water scarcity and maintenance difficulties of the AIRP. Behavioural motivations of households who discontinued or decreased use of the AIRP are discussed. Changes to AIRP design and program implementation are suggested to increase sustainability.  相似文献   

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Clean Technologies and Environmental Policy - A comparison of the emissions of gasoline–ethanol fuel and compressed natural gas (CNG) fuel used in vehicles with spark ignition engine was...  相似文献   

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In the financial market, many fixed-income analysts focus on trajectories of the hotspots. However, limited attention has been paid to the quantitative and qualitative evolution in a rapidly changing research field of fixed-income securities. This paper identifies intellectual turning points and emerging trends in the fixed-income securities field by using bibliometric methods, visualizing complicated networks including co-keyword networks, journal co-citation networks. Highly cited terms, categories, countries and institutes are detected and discussed. By using all 5915 publications published between 1997 and 2016, recorded in SCI core collection and SSCI in fixed-income securities domain and their references (101911), it can be conducted from this research that 10 top journals in the fixed-income field. The output of this article also shows the pioneer authors, the leading institutes and leading countries and regions, and what’s more, the trend of research in fixed-income securities domain. It could possibly be a valuable source for academics and practitioners working in the field of fixed-income securities.  相似文献   

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Objectives

(i) To estimate the rate ratio (RR) of use of alcohol alone, cocaine alone, and both substances simultaneously on acute injury or an aggressive incident, (ii) to compare the RRs for simultaneous use within 3 or 6 h of the event; and (iii) to compare the RRs of two measures of exposure, “hours of feeling effects” vs estimates based on self-reported quantity and frequency of use.

Methods

The study employed a case–crossover design with the frequency approach. Clients (N = 616) in substance abuse treatment for alcohol or cocaine issues from 2009 to 2012 completed a self-administered questionnaire on their substance use within 3 and 6 h before a recent injury or physically aggressive incident. Clients also reported detailed quantity and frequency information in relation to their typical substance use, as well as information on “feeling effects”. The RR of acute harms due to substance use was estimated using the Mantel–Haenszel estimator.

Results

In the 6-h window before the event, use of cocaine alone, alcohol alone and simultaneous alcohol and cocaine use were each significantly (P < 0.05) related to a recent injury and aggressive incident. Simultaneous use was not significantly greater than use of either drug alone. Estimates of RR based on simultaneous use for a 3-h window before the event were consistently larger than those based on a 6-h window, and comparisons were significant (P < 0.05) for an aggressive incident but not an injury. With reference to the two measures of exposure, three of eight comparisons of RRs were significantly larger for feeling the effects of the substance in comparison to quantity and frequency of substance use.

Conclusion

These findings are consistent with increased likelihood of harms related to the acute effects of alcohol alone, cocaine alone or simultaneous use. The results are suggestive that the acute effects of these drugs may be better measured within a 3-h time window than a 6-h window. Finally, we found that “hours of feeling effects” yielded higher estimates of RR than the quantity–frequency approach; however both measures support the overall findings.  相似文献   

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Scientometrics - This article studies the participation of women in doctorate, lecturing and research, innovation, and management activities at Universidad Politécnica de Madrid (UPM), the...  相似文献   

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This study addresses an early case of an association between a local journal and a commercial publisher in Latin America striving to improve quality. The two journals examined are Archivos de Investigación Médica (AIM), 1970–1991 and its continuation as Archives of Medical Research (AMR), 1992–2014. The aim is to characterize and compare the publishing policies and patterns of scientific communication and bibliometric indicators developed under the two different types of publication: AIM as a source of local dissemination and the commercially circulated AMR. Publishing policies, production, and citations were identified in accordance with coverage by the Web of Science and Scopus indexes. The papers and citations were grouped into three categories according to the author´s affiliation: local, regional, and external. This categorization resulted in different combinations of correlations between cited and citing papers, in addition to a distribution of collaborative production and citations by country organized by continent. The comparison of results reveals two successful publishing projects; however, editorial practices pose an irreconcilable situation between the AIM objectives as a regional journal and AMR objectives as a mainstream journal, according with dominant indicators of international competition. Some implications of this situation are discussed in the context of Latin American and Caribbean journals.  相似文献   

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