全文获取类型
收费全文 | 755篇 |
免费 | 9篇 |
国内免费 | 34篇 |
专业分类
教育 | 619篇 |
科学研究 | 117篇 |
体育 | 5篇 |
综合类 | 43篇 |
信息传播 | 14篇 |
出版年
2023年 | 2篇 |
2022年 | 9篇 |
2021年 | 11篇 |
2020年 | 12篇 |
2019年 | 4篇 |
2018年 | 2篇 |
2017年 | 7篇 |
2016年 | 8篇 |
2015年 | 5篇 |
2014年 | 44篇 |
2013年 | 30篇 |
2012年 | 47篇 |
2011年 | 62篇 |
2010年 | 35篇 |
2009年 | 47篇 |
2008年 | 46篇 |
2007年 | 75篇 |
2006年 | 64篇 |
2005年 | 53篇 |
2004年 | 49篇 |
2003年 | 45篇 |
2002年 | 36篇 |
2001年 | 25篇 |
2000年 | 23篇 |
1999年 | 18篇 |
1998年 | 2篇 |
1997年 | 14篇 |
1996年 | 7篇 |
1995年 | 4篇 |
1994年 | 4篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 1篇 |
排序方式: 共有798条查询结果,搜索用时 15 毫秒
91.
Der‐Ching Yang 《Educational studies》2004,30(4):373-389
Twenty classes in ten schools with 627 sixth‐grade students in five cities in Taiwan participated in this study. The research provides information on the performance differences among written computation, pictorial representation, symbolic representation and number sense. The results of One‐way ANOVA analysis indicate that significant difference was found among WCT, PRT, SRT and NST tests, with F=536.327, p=0.000. The a posteriori comparisons show for each pair (WCT vs PRT, WCT vs SRT, WCT vs NST, PRT vs SRT and SRT vs NST) significant difference at the 0.001 level (p=0.000), except for the pair comparison between PRT and NST. This implies that these Taiwanese students were highly skilled in written computation but their written skills were not equally transferred to use of non‐computational paths that depended on symbolic representation, pictorial representation and number sense to solve similar problems. 相似文献
92.
发展应用量子统计与膜模型计算黑洞熵的方法,对黑洞熵产生的统计根源进一步研究,利用配分函数与系统内能的关系,确定出在积分中引入的参数s,然后再应用熵与配分函数的关系,求得黑洞熵应为视界面积的2/3.在此基础上进一步修改Bekenstein-Smarr公式,给出新的黑洞热力学第一定律表达式. 相似文献
93.
ABSTRACTChildren and animals of all kinds are said to develop some degree of number sense. The search for ‘number neurons’ and neural correlates of computational thinking aims to identify biological primitives to explain the emergence of number sense. This work typically looks for the sources of number sense in organisms, but one might extend this search and study the possibility of a calculating matter more generally. Such a speculative project explores the implications of the non-human turn within the posthumanities. In this paper, I draw primarily on the work of Vicky Kirby and Gilles Deleuze in order to focus on becoming-monster through calculation. I show how calculation, as a machinic and empirical act that both serves and troubles images of mathematical truth, has always played a unique role in the production of mathematical monsters. I then discuss calculating children who participate in abacus clubs and annual abacus competitions, calculating at inhuman rates with imaginary abacuses. I argue that a new materialist philosophy of immanence demands a radically new approach to number sense. 相似文献
94.
利用电子表格Excel进行二元理想体系精馏过程中的逐板计算,可以快速且准确地得到理论塔板数、加料板位置及每一块理论塔板上的汽液组成. 相似文献
95.
Rapid developments in network systems of business service have resulted in more reliance on distributed computing, typified by "subscriber/push" architectures. Unfortunately, frequent and unexpectable network failures were routine, and downtime was not in hours, but in days. High availability has become the most important factor decreasing business risk and improving Quality of Service. Cluster technology has solved the non-stop problem on Local Area Network. However, most technologies including cluster today fail to ensure the non-stop Internet service based on Routers. With good performance on high availability and fault tolerance, quorum systems are very suitable for application to distributed business service networks. In this work, we modeled and developed a non-stop Internet service system based on a new quorum system, circle quorum system, for Boston Mutual Fund Broker, US. With five protocols, it provided highly available data services for clients on Internet. 相似文献
96.
宋娟 《邵阳学院学报(社会科学版)》2003,2(2):117-118
设计抗滑设施,确定滑坡体推力的大小是关键.一种简易计算方法——逐段传递计算法,在实际中简单易行。 相似文献
97.
利用n+1个两能级离子的纠缠GHZ态作为量子隐形传送的量子通道,提出一个有效的方案隐形传送未知n个离子的类电子纠缠GHZ态.本方案有以下显著特点:对囚禁离子振动模的加热不敏感;不需要对单个离子进行激光操控;操作简单,三步完成,成功传送的几率为1. 相似文献
98.
应用量子化学计算理论中的密度泛函方法,在B3LYP/6—311++G(d,p)水平上,从几何结构、稳定化能、磁化率增量、核独立化学位移和核磁共振化学位移等几个方面对环铝氮烷进行了计算研究,系统讨论了环铝氮烷的芳香性,并将其与环硼氮烷、苯等物质进行了比较.结果表明环铝氮烷具有较强的芳香性. 相似文献
99.
曾小明 《江苏理工大学学报(社会科学版)》2006,8(4):30-33,51
广义相对论否定了空间与时间是外在于物质的特别的实体,而是物质的相互作用与运动的显现的现象;同时,运动的定义不是相对作为背景的空间和时间,而是运动系统自身的运动关系的界定。作为显现的关系现象的时空不存在客观的时间。在此基础上的量子引力改变了物理学的认识论基础。量子引力中的各种问题带来了一系列意义深远的本体论与认识论的问题。 相似文献
100.
纳米微粒的量子尺寸效应是纳米微粒的基本性质之一,将纳米微粒的量子尺寸效应与量子力学的态叠加原理相联系谈了一点初浅看法,阐述了量子尺寸效应的本质。 相似文献