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61.
The idea of discovering patterns in data seems to be essential for decision making in our social activities. This paper presents a
simple algorithm which can be used to detect such patterns in elementary sequences of symbols. It adopts a data compression algorithm to seek
for interesting patterns, which is important in understanding the way that the input symbol stream repeats itself. In this paper, the algorithm and
related data structures are described in detail, and an illustrative example is given. 相似文献
62.
Kang Lee Catherine Ann Cameron Fen Xu Genyao Fu And Julie Board 《Child development》1997,68(5):924-934
The present study compared Chinese and Canadian children's moral evaluations of lie and truth telling in situations involving pro- and antisocial behaviors. Seven-, 9-, and 11-year-old Chinese and canadian children were presented 4 brief stories. Two stories involved a child who intentionally carried out a good deed, and the other2 stories involved a child who intentionally carried out a bad deed. When story characters were questioned by a teacher as to who had committed the deed, they either lied or told the truth. Children were asked to evaluate the story characters' deeds and their verbal statements. Overall, Chinese children rated truth telling less positively and lie telling more positively in prosocial settings than Canadian children, indicating that the emphasis on self-effacement and modesty in Chinese culture overrides Chinese children's evaluations of lying in some situations. Both Chinese and canadian children rated trugh telling positively and lie telling negatively in antisocial situations, reflecting the emphasis in both cultures on the distinction between misdeed and truth/lie telling. The findings of the present study suggest that, in the realm of lying and truth telling, a close relation between sociocultural practices and moral judgment exists. Specific social and cultural norms have an impact on children's developing moral judgments, which in turn, are modified by age and experience in a particular culture. 相似文献
63.
Numerical investigation of cavitating flow behind the cone of a poppet valve in water hydraulic system 总被引:2,自引:0,他引:2
Computational Fluid Dynamics (CFD) simulations of cavitating flow through water hydraulic poppet valves were performed using
advanced RNGk-epsilon turbulence model. The flow was turbulent, incompressible and unsteady, for Reynolds numbers greater than 43000. The
working fluid was water, and the structure of the valve was simplified as a two dimensional axisymmetric geometrical model.
Flow field visualization was numerically achieved. The effects of inlet velocity, outlet pressure, opening size as well as
poppet angle on cavitation intensity in the poppet valve were numerically investigated. Experimental flow visualization was
conducted to capture cavitation images near the orifice in the poppet valve with 30° poppet angle using high speed video camera.
The binary cavitating flow field distribution obtained from digital processing of the original cavitation image showed a good
agreement with the numerical result.
Project supported by the National Natural Science Foundation of China (No. 59835160) and Scientific Research Foundation for
Returned Overseas Chinese Scholars, State Education Ministry of China (No. 50175097) 相似文献
64.
付章建 《重庆广播电视大学学报》2007,19(3):44-46
随着中国建设银行的股份制改造以及上市,追求银行价值最大化日益明确地成为银行首要经营目标.而经济增加值作为目前评价及度量企业经营绩效、创造长期价值、同时又最能体现股东价值增长的最好指标之一,无疑为建设银行加快改革,真正成为国际上具有核心竞争力的商业银行提供了一种科学的绩效评价之策. 相似文献
65.
网络时代的高校思想政治教育工作的挑战与对策 总被引:6,自引:0,他引:6
网络技术的普及和发展,像一把双刃剑,给高校思想政治教育工作带来了机遇与挑战,它拓宽了高校思想政治工作的渠道,同时也引发许多问题,如何趋利避害进行网络思政教育是一个重要而迫切的课题. 相似文献
66.
67.
探究了多层住宅小型砼空心砌块墙体裂缝产生的原因及防治措施,对指导目前工程的设计及施工有一定的实用价值。 相似文献
68.
段富贵 《洛阳师范学院学报》2002,21(5):117-118
观察是人们获取知识信息的第一步 .观察能力的高低会对学生的学习产生重要的影响 .在化学教学中 ,有意识、有计划地培养学生的观察能力 ,使他们能够善于观察 ,并进行正确的思维是提高学生素质的一个重要环节 .教师指导的最终目标在于培养学生的独立观察能力 . 相似文献
69.
本文给出了求解扰动后新方程组的直接方法,它简捷,计算量和存贮量都不大,数值结果也表明它是相当有效的。对于替换多个方程的情况,用本方法均可直接处理。 相似文献
70.
A new site-specific nutrient management approach was developed to break the apparent attainable yield barrier of 6 t·ha−1 in the double rice cropping system of Zhejiang. On-farm experiments involving 21 rice-growing farmer families and NPK long-term
experiments commenced in 1997 in the central part of Zhejiang Province to assess the status of soil fertility and productivity
under intensive rice-rice cropping. A new site-specific nutrient management (SSNM) approach has been developed for this studied
area. Field-specific fertilizer recommendations are calculated considering indigenous nutrient supply, reasonable grain yield
targets and corresponding nutrient demand, nutrient balance and nutrient use efficiency, as well as socio-economic factors.
The agronomic performance of SSNM was tested against the farmer's fertilizer practice (FFP) in four 1998–1999 cropping seasons.
Across seasons and years, SSNM consistently increased plant nutrient uptake, grain yield and profit by about 10%–15% compared
to the FFP. Yield levels of 7.5 t·ha−1 or more seem achievable and sustainable through introduction of SSNM and improved extension services in Zhejiang Province.
Project supported by the International Fertilizer Industry Association(IFA), the Potash and Phosphate Institute, Canada (PPIC),
and International Potash Institute(IPI). 相似文献