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91.
Lotka's law and institutional productivity 总被引:1,自引:0,他引:1
The present study aims at determining the applicability of Lotka's law, negative binomial distribution and lognormal distribution for institutional productivity, in the same way as it is to authors and their productivity in the field of engineering sciences and the patents filed by industrial firms in laser S&T. The study indicates that non of the three distributions are applicable for institutional productivity in engineering sciences. However, Lotka's law holds good for full as well as truncated set of data for the patents filed by industrial firms. 相似文献
92.
Satish Kumar 《Resonance》1999,4(4):45-55
In Part 1 of this article we understood the idea of a fuzzy set. We also reviewed simple operations such as fuzzy set intersection, union, and complementation, and related these to geometry. In Part 2, we extend the idea of fuzzy sets to explain how we may develop systems that reason with fuzzy sets using fuzzy logic. The idea of extending fuzzy logic to fuzzy engineering and fuzzy function approximation is explored with a working example. It is hoped that readers will be provided with enough motivation to appreciate the use of fuzzy set theory for real world applications. 相似文献
93.
94.
Tiwari AK Mahdi AA Zahra F Chandyan S Srivastava VK Negi MP 《Indian journal of clinical biochemistry : IJCB》2010,25(4):411-418
The present study was conducted to investigate the oxidant–antioxidant status in iron deficient pregnant anemic women. One
hundred thirty pregnant women with iron deficiency anemia (IDA) were divided into three groups, namely mild (50), moderate
(50) and severe (30) anemic along with pregnant healthy women as controls (50). The complete blood count, plasma lipid peroxidation
products, enzymatic and non-enzymatic antioxidants were measured according to respective protocols. The levels of complete
blood count, iron, ferritin along with antioxidant enzymes namely catalase, superoxide dismutase, glutathione peroxidase,
glutathione reductase and reduced glutathione were significantly reduced in all IDA groups. However, the level of oxidized
glutathione, lipid peroxides, protein carbonyls, conjugated dienes were found significantly increased in all anemic patients.
Antioxidant vitamins, namely C, E and A were also found significantly decreased in IDA patients. On the basis of our results,
it may be concluded that IDA tends to increase the pro-oxidant components, which may result in various complications including
peroxidation of vital body molecules resulting in increased risk for pregnant women as well as fetus. 相似文献
95.
The correlation between antioxidant capacity and oxidative damage during aging has been reported in several tissues in different
species. Glutathione-S-transferases (GST) can metabolise endogenous and exogenous toxins and carcinogens by catalysing the
conjugation of diverse electrophiles with reduced glutathione (GSH). We observe a significant (P < 0.001) increase in plasma GST activity as a function of human age (r = 0.5675). A significant (P < 0.001) positive correlation (r = 0.8979) is observed between GST activity and total plasma antioxidant potential measured
as ferric reducing ability of the plasma (FRAP). GST activity and red cell intracellular GSH also show a significant positive
correlation (r = 0.7014). We hypothesize that the increased activity of plasma GST is a manifestation of increased generation
of ROS and a concomitant decrease in the level of plasma antioxidant capacity during aging. 相似文献
96.
Every individual should be entrusted with an internal driver to strive their best towards achieving their potential and to manifest their performance through innovative means. This can be reached only under circumstances where the abstract human values and principles are recognized and indoctrinated in the culture. The strategies discussed in this article will serve as input in proposing the areas of focus toward the practice of human governance. 相似文献
97.
98.
Tamara M. Walser 《Innovative Higher Education》2009,34(5):299-306
Although student self-assessment is considered a critical component of assessment for learning, its use and related research
are rare in higher education. This article describes an action research study of self-assessment as an instructional strategy
in two university courses. Results indicate that self-assessment exercises provided students the opportunity to reflect on
the course and their performance, helped them monitor their own progress, motivated them to do well in the course, and provided
them the opportunity to give feedback to the instructor. Additionally, from the instructor perspective, the exercises provided
useful feedback for course improvement and facilitated interactions and relationships with students. 相似文献
99.
Pavlo Antonenko Fred Paas Roland Grabner Tamara van Gog 《Educational Psychology Review》2010,22(4):425-438
Application of physiological methods, in particular electroencephalography (EEG), offers new and promising approaches to educational
psychology research. EEG is identified as a physiological index that can serve as an online, continuous measure of cognitive
load detecting subtle fluctuations in instantaneous load, which can help explain effects of instructional interventions when
measures of overall cognitive load fail to reflect such differences in cognitive processing. This paper presents a review
of seminal literature on the use of continuous EEG to measure cognitive load and describes two case studies on learning from
hypertext and multimedia that employed EEG methodology to collect and analyze cognitive load data. 相似文献
100.
Fleurie Nievelstein Tamara van Gog Henny P. A. Boshuizen Frans J. Prins 《Instructional Science》2010,38(1):23-35
Due to the complexity of the legal domain, reasoning about law cases is a very complex skill. For novices in law school, legal
reasoning is even more complex because they have not yet acquired the conceptual knowledge needed for distilling the relevant
information from cases, determining applicable rules, and searching for rules and exceptions in external information sources
such as lawbooks. This study investigated the role of conceptual knowledge in solving legal cases when no information sources
can be used. Under such ‘unsupported’ circumstances, novice and advanced students performed less well than domain experts,
but even experts’ performance was rather low. The second question addressed was whether novices even benefit from the availability
of information sources (i.e., lawbook), because conceptual knowledge is prerequisite for effective use of such sources. Indeed
availability of the lawbook positively affected performance only for advanced students but not for novice students. Implications
for learning and instruction in the domain of law are discussed. 相似文献