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Paradigmatic Processes in Culture Change 总被引:1,自引:0,他引:1
ANTHONY F. C. WALLACE 《American anthropologist》1972,74(3):467-478
Paradigmatic processes in culture change are defined, in the sense of Thomas Kuhn, as the consequence of long-continued deliberate effort by numbers of persons to innovate within a recognized technical, artistic, or intellectual tradition (or "school" or "discipline"). The evolving paradigm will often, after a certain point of development, attract exploitation; there will then occur various functionally entailed social-cultural consequences; and ultimately efforts will be made to rationalize the change in religious, ethical, and philosophical terms. 相似文献
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We review data from both ethology and psychology about generalization, that is how animals respond to sets of stimuli including familiar and novel stimuli. Our main conclusion is that patterns of generalization are largely independent of systematic group (evidence is available for insects, fish, amphibians, reptiles, birds and mammals, including humans), behavioural context (feeding, drinking, courting, etc.), sensory modality (light, sound, etc.) and of whether reaction to stimuli is learned or genetically inherited. These universalities suggest that generalization originates from general properties of nervous systems, and that evolutionary strategies to cope with novelty and variability in stimulation may be limited. Two major shapes of the generalization gradient can be identified, corresponding to two types of stimulus dimensions. When changes in stimulation involve a rearrangement of a constant amount of stimulation on the sense organs, the generalization gradient peaks close to familiar stimuli, and peak responding is not much higher than responding to familiar stimuli. Contrary to what is often claimed, such gradients are better described by Gaussian curves than by exponentials. When the stimulus dimension involves a variation in the intensity of stimulation, the gradient is often monotonic, and responding to some novel stimuli is considerably stronger than responding to familiar stimuli. Lastly, when several or many familiar stimuli are close to each other predictable biases in responding occur, along all studied dimensions. We do not find differences between biases referred to as peak shift and biases referred to as supernormal stimulation. We conclude by discussing theoretical issues. 相似文献
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A Paradigmatic Shift in the Search for the Origin of Agriculture 总被引:1,自引:0,他引:1
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According to the discrimination hypothesis (White, 2002), remembering is a delay-specific discrimination made at the time of retrieval. In the present experiment the delay-specific nature of the discrimination was made explicit by making correct choices in a delayed matching-to-sample task performed by pigeons conditional on whether the retention interval was short or long. Retention interval was varied over several durations in a maintained generalization test without reinforcement for correct matching responses. Opposing gradients demonstrated generalization of delay-specific remembering, consistent with the view that the temporal dimension of the retention interval can be treated in the same way as non-temporal dimensions of the sample stimulus. 相似文献
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Dr. R. K. Singh Dr. rer. nat. K. Bellmann 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1972,42(8):331-334
Summary The present investigation was undertaken to study the problem of generalization of the selection index in plant breeding. It was found that specific selection indices brought about the maximum genetic advance, provided that they were used for selection in the specific populations. If these indices were used as foreign indices the gain was negligible. The general selection indices, which were based on corrected pooled information from different experiments, were found to be as efficient as the specific indices. The problems of sampling, specific populations and base population of a crop species, and the application of general indices in a practical breeding programme have been discussed in detail. 相似文献
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Neural-space generalization of a topological transformation 总被引:1,自引:0,他引:1
G. Josin 《Biological cybernetics》1988,59(4-5):283-290
An investigation is performed to assess the generalization capability found in neural network paradigms to approximate a 2-dimensional coordinate (topological) transformation. A developed strategy uses the example to give a physical meaning to what is meant by generalization. The example shows how to use a neural network paradigm to generalize a two-degree of freedom topological transformation from cartesian end-point coordinates to corresponding joint angle coordinates based only on examples of the mapping. The importance of this example is that it provides a clear understanding of how and what a neural network is actually communications and brings a theoretical idea to a useful understanding. When examples characterize the topology, a collective generalization property begins to emerge and the network learns the topology. If the network is presented with additional examples of the transformation, the network can generate the corresponding joint angles to any unseen position, that is, by generalization. It is also significant that the network's generalization property emerges from the network based on very few training examples! Further, the networks power exists with very few neurons. Results suggest the use of the paradigm's generalization capability to provide solutions to unknown or intractable algorithms for applications. 相似文献
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A new aspect for neuronal networks is presented. The aspect is based on the concept of ruledynamics which was originally proposed by one of the authors, Aizawa. The concept of ruledynamics were modeled on the two states cellular automata of neighborhood-three (CA(2/3)). A brief review of ruledynamics is also presented, because most publications of the authors so far have been in Japanese. Our concise assertion in the present paper is that a neuronal network realizes a kind of ruledynamics. This assertion is a speculation on the comparison of McCulloch-Pitts neuron networks with ruledynamics on CA(2/3). A trial is originally shown to demonstrate that a McCulloch-Pitts neuron network can be imitated by an extended version of ruledynamics on CA(2/3). 相似文献
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Paradigmatic status of an endo- and exoglucanase and its effect on crystalline cellulose degradation
Sarah Mora?s Yoav Barak Raphael Lamed David B Wilson Qi Xu Michael E Himmel Edward A Bayer 《Biotechnology for biofuels》2012,5(1):1-9
Background
Presently, different studies are conducted related to the topic of biomass potential to generate through anaerobic fermentation process alternative fuels supposed to support the existing fossil fuel resources, which are more and more needed, in quantity, but also in quality of so called green energy. The present study focuses on depicting an optional way of capitalizing agricultural biomass residues using anaerobic fermentation in order to obtain biogas with satisfactory characteristics.. The research is based on wheat bran and a mix of damaged ground grains substrates for biogas production.Results
The information and conclusions delivered offer results covering the general characteristics of biomass used , the process parameters with direct impact over the biogas production (temperature regime, pH values) and the daily biogas production for each batch relative to the used material.Conclusions
All conclusions are based on processing of monitoring process results , with accent on temperature and pH influence on the daily biogas production for the two batches. The main conclusion underlines the fact that the mixture batch produces a larger quantity of biogas, using approximately the same process conditions and input, in comparison to alone analyzed probes, indicating thus a higher potential for the biogas production than the wheat bran substrate. Adrian Eugen Cioabla, Ioana Ionel, Gabriela-Alina Dumitrel and Francisc Popescu contributed equally to this work 相似文献11.
Fahle M 《Current opinion in neurobiology》2005,15(2):154-160
Perceptual learning improves performance on many tasks, from orientation discrimination to the identification of faces. Although conventional wisdom considered sensory cortices as hard-wired, the specificity of improvement achieved through perceptual learning indicates an involvement of early sensory cortices. These cortices might be more plastic than previously assumed, and both sum-potential and single cell recordings indeed demonstrate plasticity of neuronal responses of these sensory cortices. However, for learning to be optimally useful, it must generalize to other tasks. Further research on perceptual learning should therefore, in my opinion, investigate first, the conditions for generalization of training-induced improvement, second, its use for teaching and rehabilitation, and third, its dependence on pharmacological agents. 相似文献
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A theorem of Jacobi and its generalization 总被引:1,自引:0,他引:1
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Despite the development of diversity indices in community ecology that incorporate both richness and evenness, pollination biologists commonly use only pollinator richness to estimate generalization. Similarly, while pollination biologists have stressed the utility of pollinator importance, incorporating both pollinator abundance and effectiveness, importance values have not been included in estimates of generalization in pollination systems. In this study, we estimated pollinator generalization for 17 plant species using Simpson’s diversity index, which includes richness and evenness. We compared these estimates with estimates based on only pollinator richness, and compared diversity estimates calculated using importance data with those using only visitation data. We found that pollinator richness explains only 57–65% of the variation in diversity, and that, for most plant species, pollinator importance was determined primarily by differences in visitation rather than by differences in effectiveness. While simple richness may suffice for broad comparisons of pollinator generalization, measures that incorporate evenness will provide a much more accurate understanding of generalization. Although incorporating labor-intensive measurements of pollinator effectiveness are less necessary for broad surveys, effectiveness estimates will be important for detailed studies of some plant species. Unfortunately, at this point it is impossible to predict a priori which species these are. 相似文献
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Wright BA Zhang Y 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2009,364(1515):301-311
The ability to detect and discriminate attributes of sounds improves with practice. Determining how such auditory learning generalizes to stimuli and tasks that are not encountered during training can guide the development of training regimens used to improve hearing abilities in particular populations as well as provide insight into the neural mechanisms mediating auditory performance. Here we review the newly emerging literature on the generalization of auditory learning, focusing on behavioural investigations of generalization on basic auditory tasks in human listeners. The review reveals a variety of generalization patterns across different trained tasks that can not be summarized with a simple rule, and a diversity of views about the definition, evaluation and interpretation of generalization. 相似文献
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H B Stauffer 《Journal of theoretical biology》1979,77(1):19-25
Pielou's index of non-randomness a measuring the distribution of point spatial patterns on a plane generalizes to an index in n-dimensional Euclidean space En. This defines an index of non-randomness measuring the extent of regularity, randomness, or aggregation in distributions of point spatial patterns in En. 相似文献
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