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991.
992.
Abraham Bookstein Shmuel T. Klein Timo Raita 《Information processing & management》1997,33(6):745-760
Many of the most effective compression methods involve complicated models. Unfortunately, as model complexity increases, so does the cost of storing the model itself. This paper examines a method to reduce the amount of storage needed to represent a Markov model with an extended alphabet, by applying a clustering scheme that brings together similar states. Experiments run on a variety of large natural language texts show that much of the overhead of storing the model can be saved at the cost of a very small loss of compression efficiency. 相似文献
993.
R. Kumar S. B. Pachori G. K. Senger Satyanand L. D. Joshi 《Indian journal of clinical biochemistry : IJCB》1994,9(2):72-74
Aim of present study was to compare the adenosine deaminase (ADA) activity in various types of arthritis conditions with synovial
effusion. No. significant difference was observed in ADA activity in serum of control and study groups but results have shown
a definite pattern of ADA activity in synovial fluid in various arthritic conditions. The highest value of ADA activity was
observed in synovial fluid of patients with tubercular arthritis followed by rheumatoid, septic, osteo and post traumatic
arthritis. Thus measurement of ADA activity in synovial fluid can be used as a parameter of differential diagnosis of arthritis
specially tubercular in initial stages. 相似文献
994.
995.
For some 300 years the modelling of uncertainty in the sciences has been totally dominated by probabilistic methods. Now, following major criticism of the theoretical foundations of probability theory, other approaches to dealing with uncertainty are being explored. 相似文献
996.
997.
998.
This paper constitutes an attempt to explore trends, issues and challenges that emerge when three different cohorts of pre-service teachers debate contemporary issues in science education at the University of Botswana. Apart from the author's experience of teaching the course, the impetus for this study also comes from a growing interest in the contemporary literature in the need for teachers who, in the context of globalization and knowledge economy, are ‘self-reforming’ through continually addressing the key issues of their profession. Unfortunately, the current situation is such that this burden of interrogation falls heaviest on teachers, despite their lack of skills in undertaking the task. 相似文献
999.
1000.
Not all young children benefit from book exposure in preschool age. It is claimed that the ability to hold information in
mind (short-term memory), to ignore distraction (inhibition), and to focus attention and stay focused (sustained attention) may have a moderating effect on children’s reactions to the home literacy environment. In a group of 228 junior kindergarten
children with a native Dutch background, with a mean age of 54.29 months (SD = 2.12 months), we explored therefore the relationship
between book exposure, cognitive control and early literacy skills. Parents filled in a HLE questionnaire (book sharing frequency
and an author recognition checklist as indicator of parental leisure reading habits), and children completed several tests
in individual sessions with the researcher (a book-cover recognition test, PPVT, letter knowledge test, the subtests categories
and patterns of the SON, and cognitive control measures namely digit span of the KABC, a peg tapping task and sustained attention
of the ANT). Main findings were: (1) Children’s storybook knowledge mediated the relationship between home literacy environment
and literacy skills. (2) Both vocabulary and letter knowledge were predicted by book exposure. (3) Short-term memory predicted
vocabulary over and above book exposure. (4) None of the cognitive control mechanisms moderated the beneficial effects of
book exposure. 相似文献