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91.
目的本文探索了中医院校药理学大班案例教学法。方法将案例引入课堂教学,将小组讨论放在课后,加大课后作业和集中辅导。结果该法可以使理论教学生动有趣。课后讨论有利于培养学生主动学习的能力。结论大班案例教学法是药理学教学中值得推广并且行之有效的教学方法。  相似文献   
92.
In the Budding Science and Literacy project, we explored how working with an integrated inquiry-based science and literacy approach may challenge and support the teaching and learning of science at the classroom level. By studying the inter-relationship between multiple learning modalities and phases of inquiry, we wished to illuminate possible dynamics between science inquiry and literacy in an integrated science approach. Six teachers and their students were recruited from a professional development course for the current classroom study. The teachers were to try out the Budding Science teaching model. This paper presents an overall video analysis of our material demonstrating variations and patterns of inquiry-based science and literacy activities. Our analysis revealed that multiple learning modalities (read it, write it, do it, and talk it) are used in the integrated approach; oral activities dominate. The inquiry phases shifted throughout the students' investigations, but the consolidating phases of discussion and communication were given less space. The data phase of inquiry seems essential as a driving force for engaging in science learning in consolidating situations. The multiple learning modalities were integrated in all inquiry phases, but to a greater extent in preparation and data. Our results indicate that literacy activities embedded in science inquiry provide support for teaching and learning science; however, the greatest challenge for teachers is to find the time and courage to exploit the discussion and communication phases to consolidate the students' conceptual learning.  相似文献   
93.
《Child abuse & neglect》2013,37(12):1109-1113
ObjectiveThe rate of multiple births has increased over the last two decades. In 1982, an increased frequency of injuries among this patient population was noted, but few studies have evaluated the increased incidence of maltreatment in twins. The study aim was to evaluate the features of all multiple-birth children with substantiated physical abuse and/or neglect over a four-year period at a major children's hospital.Study design and methodsA Retrospective chart review was conducted of multiple-gestation children in which at least one child in the multiple set experienced child maltreatment from January 2006 to December 2009. Data regarding the child, injuries, family, and perpetrators were abstracted. We evaluated whether family and child characteristics were associated with maltreatment, and whether types of injuries were similar within multiple sets. For comparison, data from the same time period for single-birth maltreated children also were abstracted, including child age, gestational age at birth, and injury type.ResultsThere were 19 sets of multiple births in which at least one child had abusive injuries and/or neglect. In 10 of 19 sets (53%), all multiples were found to have a form of maltreatment, and all children in these multiple sets shared at least one injury type. Parents lived together in 63% of cases. Fathers and mothers were the alleged perpetrator in 42% of the cases. Multiple-gestation-birth maltreated children were significantly more likely than single-birth maltreated children to have abdominal trauma (13% vs. 1%, respectively; p < .01), fractures (83% vs. 39%; p < .01), and to be injured at a younger mean age (12.8 months vs. 34.8 months; p < .01).ConclusionsSiblings of maltreated, multiple-gestation children often, but not always, were abused. In sets with two maltreated children, children usually shared the same modes of maltreatment. Multiples are significantly more likely than singletons to be younger and experience fractures and abdominal trauma. The findings support the current standard practice of evaluating all children in a multiple set when one is found to be abused or neglected.  相似文献   
94.
IMM算法只有在精确选取模型时才能取得良好的效果,本文采用一种新的"当前"Jerk模型(CS-Jerk模型)与匀速运动模型进行交互,讨论并证明了新的"当前"统计Jerk模型,即CS-Jerk模型对突发机动自适应跟踪性能好。仿真结果表明,在跟踪一般机动目标时,本文算法的误差和"当前"统计模型与CV模型交互的IMM算法相当;在跟踪突发机动目标时,其误差明显小于"当前"统计模型与CV交互的IMM算法。  相似文献   
95.
嫩江流域径流量多时间尺度特征分析   总被引:3,自引:0,他引:3  
徐东霞  章光新  冯夏清 《资源科学》2009,31(9):1592-1598
目前在全球气候变化与人类活动的双重影响下,陆地水文循环发生了深刻的变化,近50年来,嫩江流域径流过程发生了巨大变化,加剧了水资源的短缺和时空变异性,并带来一系列突出的水与生态环境问题.本文根据嫩江、石灰窑、同盟、江桥、大赉水文站1956年~2006年51a的径流资料,采用Morlet小波对嫩江流域径流序列进行了多时间尺度研究,结果表明:流域径流演变过程存在明显的多时间尺度特征,具有8a、20a、45a多尺度的周期变化规律,且以45a尺度的年代周期信号最强,表明45a尺度的年代周期变化最为明显;嫩江、江桥气象站的降水周期与上述径流资料基本一致,说明降水的变化是流域径流演变过程的重要自然控制因素.  相似文献   
96.
本文介绍了多任务版本的实时系统调度算法.该算法能够满足实时系统中的关键性任务在最坏情况下运行时,仍可满足截止时闻的要求.通过为实时系统中的关键性任务设置两个任务版本,即主态和从态版本.主态任务版本具有较好的质量,从态任务版本只提供最基本的功能,运行时间较短.在最坏情况下避免调度主态任务版本,来满足实时调度的实时性要求.  相似文献   
97.
基于MODIS数据的泰国林地资源提取   总被引:1,自引:1,他引:0  
吕婷婷  孙晓宇  于伯华 《资源科学》2008,30(7):1076-1083
遥感技术的发展为我们对世界资源的研究提供了新的手段,克服了世界资源研究过程中数据缺乏的困难。泰国曾经是林地资源丰富的国家,尤其是热带林地资源,但是近几十年来林地面积在不断减少,带来了一系列生态问题。选用MOD09Q1的1、2波段,MOD09A1的第6波段以及MOD11A2数据产品提取了泰国林地分布情况。由于泰国地处热带地区云雾噪音为林地的提取造成了很大的不确定性,为了有效去除云雾噪音影响,结合NDVI、NDSI、LST多参数在林地提取中的优势对泰国林地进行提取。采用泰国2003年统计年鉴提供的分省林地面积以及2003年p131r47和p131r48共2景ETM影像进行了精度验证。结果表明,利用多参数综合分类方法对林地提取精度较高,通过与2003年统计年鉴数据进行回归分析发现二者存在明显的线性关系,决定系数达到0.9264。  相似文献   
98.
本文通过对国内外掌上技术在学校数学教学中使用的分析 ,阐述了笔者关于掌上技术在学校数学教学使用中的三个观点 ;更为重要的是 ,笔者提出了在新技术的参与下“学校教学”教育观的三个原则  相似文献   
99.
区间数多属性决策问题的分析方法   总被引:3,自引:0,他引:3  
为了解决带有不确定性区间数的多属性决策问题 ,首先必须确定权系数的取值。本文就权系数的两种不同状态 ,给出了两种决策分析方法。每种方法通过求解模型来确定权系数的具体数值 ,最后得出排序方案  相似文献   
100.
Continued advancement in the field of physical activity and health promotion relies heavily on the synthesis of rigorous scientific evidence. As such, systematic reviews and meta-analyses of randomized controlled trials have led to a better understanding of which intervention strategies are superior (i.e., produce the greatest effects) in physical activity-based health behavior change interventions. Indeed, standard meta-analytic approaches have allowed researchers in the field to synthesize relevant experimental evidence using pairwise procedures that produce reliable estimates of the homogeneity, magnitude, and potential biases in the observed effects. However, pairwise meta-analytic procedures are only capable to discerning differences in effects between a select intervention strategy and a select comparison or control condition. In order to maximize the impact of physical activity interventions on health-related outcomes, it is necessary to establish evidence concerning the comparative efficacy of all relevant physical activity intervention strategies. The development of network meta-analysis (NMA)—most commonly used in medical-based clinical trials—has allowed for the quantification of indirect comparisons, even in the absence of direct, head-to-head trials. Thus, it stands to reason that NMA can be applied in physical activity and health promotion research to identify the best intervention strategies. Given that this analysis technique is novel and largely unexplored in the field of physical activity and health promotion, care must be taken in its application to ensure reliable estimates and discernment of the effect sizes among interventions. Therefore, the purpose of this review is to comment on the potential application and importance of NMA in the field of physical activity and health promotion, describe how to properly and effectively apply this technique, and suggest important considerations for its appropriate application in this field. In this paper, overviews of the foundations of NMA and commonly used approaches for conducting NMA are provided, followed by assumptions related to NMA, opportunities and challenges in NMA, and a step-by-step example of developing and conducting an NMA.  相似文献   
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