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1.
陈涛 《甘肃科技纵横》2010,39(5):100-102
基于CSSCI引文数据库,运用h指数及h衍生指数对《档案学研究》进行评价,对h指数及h衍生指数关系进行研究。并通过普莱斯定律、h指数、总被引频次三个方面来确定出其核心作者并对其核心作者进行h指数及h衍生指数测定,分析了《档案学研究》h指数偏低的原因。  相似文献   

2.
目的:系统了解1985~2000年间蒙古族中小学生形态发育状况及变化趋势,为改善学生健康状况提供依据.方法:以1985,2000年蒙古族学生体质健康调研资料为样本,选择身高、体重、胸围3项形态指标及体重指数和维尔维克指数2项派生指标进行统计分析.结果:15年间蒙古族中小学生身高、体重、胸围生长发育均有不同程度的增长,其城市学生增长值多数高于乡村学生.结论:蒙古族中小学生多数年龄组具有形态生长速度加快、快速增长期提前和持续增长期延长的特点。  相似文献   

3.
应用计算机编程 ,根据学生考试成绩 ,对试卷进行分析 .分析中采用难度指数 (P)及区别度指数 (R)等多种分析参数 ,对试题及全卷质量作出分析 ,并绘制学生成绩分布图 ,同时对学生成绩是否成正态分布作出判断 .为从学生对教学内容掌握情况及教师的教学情况两方面进行客观评价提供了依据  相似文献   

4.
用判别分析方法对武汉市2003年中考体育考试项目及评价指标进行了统计处理,判别分析结果表明,武汉市城区初三(15岁)男、女学生的体质健康状况总体优于乡村学生,但约1/4城乡学生的体质健康水平有交叉现象.武汉市选择BMI指数、肺活量/体重指数、握力/体重指数、立定跳远4项指标在中考体育考试中对学生的体质健康状况进行评价是科学的.  相似文献   

5.
为探讨不同的体重指数与大学生各项体质健康指标的关系,以4802名大学生为研究对象,分别实施各项体质健康测验.依其体重指数将学生分为低体重、正常体重、超重及肥胖四组,以体重指数为自变量,其他体质健康指标为因变量,进行单因素方差分析,并进行均数的多重比较。结果显示:体质健康指标在不同的体重指数之间的变化趋势各不相同;正常体重学生心血管功能、呼吸机能、手臂力量、下肢爆发力均优于低体重组(除呼吸机能外)、超重、肥胖组学生;低体重(除呼吸机能外)、超重、肥胖对学生身体机能、素质均产生负面影响。  相似文献   

6.
董纪文 《科技咨询导报》2007,(4):125-125,127
本文采用较能客观反映真实足弓的指标——足弓指数,对预备班、初中和高中足弓发育情况进行研究。结果表明:预备班至中学初中的高中生时期,是足弓发育时期。在这一时期。足弓指数随年龄增长而增长,扁平足发生率则随年龄增大而减少;初中的高中生时期是踏跳(用力)腿逐渐形成的阶段,其足弓指数平均值大于非踏跳(用力)腿,提示预备班学生、初中学生多进行跑跳练习,有助于高中生初中生.足弓的正常发育。  相似文献   

7.
试卷分析计算机应用软件的研究与开发   总被引:3,自引:0,他引:3  
应用计算机编程,根据学生考试成绩,对试卷进行分析,分析中采用难度指数(P)及区别度指数(R)等多种分析参数,对试题及全卷质量作出分析,并绘制学生成绩分布图,同时对学生成绩是否成正态分布作出判断,为从学生对教学内容掌握情况及教师的教学情况两方面进行客观评价提供了依据。  相似文献   

8.
通过对青海大学学生的身高、体重形态检测,又以问卷形式对学生营养状况的调查,其结果显示,青海大学学生身体形态指数总体呈偏态分布,部分学生每天对碳水化合物、蛋白质、维生素、无机盐的摄取量不足。建议学校加强对学生的体育营养保健教育,引导学生科学饮食,利用运动进行形体美化。  相似文献   

9.
高校学生BMI分布特征的研究与分析   总被引:12,自引:0,他引:12  
近年来,高校学生肥胖人群已经受到人们的关注。将大学生与儿童少年及成年人群的BMI分布特征作比较,指出高校学生BMI指数类型上的分布特征。同时发现,体重过轻、超重及肥胖的高校男女生BMI指数峰度及卡方检验差异显著。通过对大学生BMI指数现状分析以及研究不同性别大学生BMI分布差异性,提出了改进、开发高校体育课程资源,在体育教学中合理有效的对学生进行体育技能与健康教育的建议。  相似文献   

10.
钦州湾近岸海域水质污染状况评价   总被引:1,自引:1,他引:0       下载免费PDF全文
【目的】调查及评价钦州湾近岸海域水质污染程度。【方法】2010年3月(春季)及2010年9月(秋季)在钦州湾近岸海域布设9个站位进行水质、浮游植物及浮游动物调查。采用水质综合污染指数及生物多样性指数对调查结果进行评价。【结果】钦州湾近岸海域春季、秋季水质综合污染指数平均值分别为3.20、3.68;浮游植物多样性指数分别为3.37、3.35;浮游动物多样性指数分别为2.33、2.89。【结论】以水质综合污染指数评价,2010年钦州湾近岸海域污染等级为轻污染;以浮游植物多样性指数评价,污染等级为轻度污染至无污染;以浮游动物多样性指数进行评价,污染等级为轻中污染。相对于浮游动物多样性指数,浮游植物多样性指数能更灵敏地指示和评价海洋环境的污染形势,但其评价标准和方法有待更多的调查和研究来进行验证和修正。单一利用生物多样性指数进行海域污染评价,具有一定的局限性,但仍可在一定程度上反映出海洋环境的污染程度。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

14.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

15.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

16.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

17.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

18.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

19.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

20.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

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