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81.
The Harappan civilization, the world's fourth great civilization after those of Egypt, Mesopotamia, and China flourished in the valley of the Indus three thousand years ago. As yet little is known about it, but one enormous town — Mohenjo-Daro — has survived. This has been only partially excavated and has yielded just a few scraps of information which have provided the basis for some fanciful theories. The author of this article had developed an interesting new approach. Combining a re-examination of the documentation that has accumulated over the past 50 years with an investigation of the actual remains, he has obtained some exciting results which shed new light on the overall planning, architecture, and development of the town over the centuries, thus providing a fresh understanding of the Harappan civilization itself.  相似文献   
82.
This paper treats the problem of transmitting a Gaussian discrete-time Markov process over a time-discrete additive white Gaussian channel with noiseless feedback which is subjected to statistically unknown jamming noise (satisfying a given power constraint). The channel is used more than once during the interval between the production of successive source letters, and the jamming noise is either allowed to be correlated with the encoder output, or forced to be totally independent of it. The complete solution obtained in the paper under a minimax criterion indicates that the optimum encoder-decoder structures are linear,and the least favorable jamming noise is a Gaussian process.  相似文献   
83.
Infants with respiratory distress syndrome (RDS) may suffer from severe hypoxia, asphyxia. In this study, we aimed to evaluate serum ischemia-modified albumin (IMA) level as a diagnostic marker for hypoxia in preterm infants with RDS. Thirty-seven premature newborns with RDS were allocated as the study group and 42 healthy preterm neonates were selected as the control group. IMA was measured as absorbance unit (ABSU) in human serum with colorimetric assay method which is based on reduction in albumin cobalt binding. IMA levels were significantly higher in neonates with RDS as compared to the control group (P < 0.001). Cut-off value of IMA (ABSU) was 0.72, the sensitivity level was 91.9 %, the specificity was 78.6 %, positive predictive value was 79.1 % and negative predictive value was 91.7 % at RDS. Area under curve values was 0.93 (P < 0.001; 95 % CI, 0.88–0.98) in the receiver operating characteristic curve. We concluded that elevated blood IMA levels might be accepted as a useful marker for hypoxia in newborn with RDS.  相似文献   
84.
Fault finding is a puzzling task, at work and in technical and professional training. Our purpose is to contribute to an analysis of the required competencies and mainly to a characterisation of the evolution steps in knowledge and action organisation from novice to expert. Eight grown-up preparing a professional certificate in engine mecanics were observed and filmed while they were working out the diagnosis of an ignition trouble on a real equipment. The theory of functionning registers (deducted from Piaget’s theory) is considered as a relevant frame for our activity analysis. So, four competencies patterns has been outlined on the basis of errors extension, circuit functionning representations which were infered from schema interpretations, and trouble-shooting strategies denoted by control procedures. Some consequences about training are examined.  相似文献   
85.
Educational technology research and development - This paper studies learners’ emotion awareness in university level academic contexts as a first step to help learners regulate their...  相似文献   
86.
87.
随着社会的发展,开展“国际理解教育”是学校发展的必然趋势,而将环保教育有意识地与国际理解教育相结合则是上海市第三女子中学目前努力探索的重要课题。在一系列教育活动中,学校以环保课程为依托,以学生环保社团为组织核心,与国际环保组织“Roots & Shoots”、市内各类环保团体形成活动链,积极开展各级各类环保活动,在活动中为学生搭建通向世界的桥梁,加深学生乃至社会对环保的认识。  相似文献   
88.
介绍了一例超重失重演示仪的制作及演示情况,该演示仪能具体得到超重失重数值,演示效果好。  相似文献   
89.
The use of networks in education is experiencing world-wide growth. Many schools have taken advantage of the reduction of price in modems, the emergence of electronic bulletin boards and world-wide web pages with educational content, and the availability of software for public participation in networks. Nevertheless, little information is available about the quality and quantity of existing network traffic; information that would allow organizations, network project administrators and supporters, to evaluate its impact, know its usage, evolution and projections. This paper presents some of the traffic monitoring mechanisms presently in use in a Chilean educational network (the Enlaces Project), together with examples of the information collected through these mechanisms.  相似文献   
90.
This study examined the value of using a group‐centered approach to evaluate process quality of early childhood education and care (ECEC). Is observed support of group processes a different aspect of classroom quality, and does it predict children's collaborative play in ECEC in the Netherlands? In two play situations, 37 teachers and 120 two‐ to four‐year‐old children were observed with the Classroom Assessment Scoring System (CLASS) Toddler and two new measures. In a two‐level structural equation model, teachers’ support of group processes was positively related to the CLASS domains and to children's collaborative play, over and above the effect of children's cognitive ability and social competence. These findings suggest that ECEC quality evaluation could be enriched by adding group‐centered indicators of classroom quality.  相似文献   
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