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21.
《Ergonomics》2012,55(12):1966-1984
Two experiments investigated the effect of making errors during training (error training) on a driving simulator versus learning from examples of errors (guided error training) on driving skill and confidence. Experiment 1 indicated that compared with errorless learning (where participants drove through a training run not designed to elicit errors), error training led to significantly better transfer to driving tests that were analogous to those situations encountered in training and more effective use of strategies for coping with a novel driving situation. Error training also reduced self-confidence in driving skill at the end of training relative to errorless learning. Experiment 2 provided weak evidence of the superiority of guided error training over errorless learning (where the driver in the video did not make any errors) on analogous tests, and no evidence of transfer to a novel test. Furthermore, guided error training did not influence self-confidence in driving skill. The potential value of driving simulators in providing active processing during driver training is discussed, along with the effects of passive and active exposure to errors on driver confidence. 相似文献
22.
数据挖掘技术在教学评价中的应用 总被引:23,自引:0,他引:23
数据挖掘技术是在海量数据中提取有用信息的有效手段,它被广泛应用于经济效益巨大的金融、商业等领域,而在教学评价中应用较少,这使得一些对教学效果有较大影响的因素往往被忽视。该文介绍了把数据挖掘技术引入网上教学评价中的有益尝试。 相似文献
23.
24.
The single bootstrap already is popular in economics, though the double bootstrap has better convergence properties. We discuss the theory and implementation of the double bootstrap, both with and without the pivotal transformation, and give detailed examples of each. One example is a nonlinear double bootstrap of a Cobb-Douglas production function, and explains the use of Gauss-Newton Regressions as a device to decrease computational time. Another example is double bootstrapping elasticities from a translog production function. 相似文献
25.
Format dependence implies that assessment of the same subjective probability distribution produces different conclusions about over- or underconfidence depending on the assessment format. In 2 experiments, the authors demonstrate that the overconfidence bias that occurs when participants produce intervals for an uncertain quantity is almost abolished when they evaluate the probability that the same intervals include the quantity. The authors successfully apply a method for adaptive adjustment of probability intervals as a debiasing tool and discuss a tentative explanation in terms of a naive sampling model. According to this view, people report their experiences accurately, but they are naive in that they treat both sample proportion and sample dispersion as unbiased estimators, yielding small bias in probability evaluation but strong bias in interval production. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
26.
鉴于ADB610钢冲击功(Akv)数据的分散性。采用多种概率统计模型对其进行拟合,并采用相关系数法和柯尔莫哥洛夫~斯米尔诺夫检验法(K-S检验法)检验拟合效果,检验结果显示三参数威布尔分布最优。通过对ADB610钢冲击功置信区间的研究,得到置信度95%、可靠度99.9%的置信区间为[139.5J,217.1J]。最后对冲击功进行求解,以获得一定可靠度下的安全冲击功,分别得到对应可靠度为0.9,0.975和0.99时的安全冲击功228.7J,210.1J和200.7 J。 相似文献
27.
Moving object detection is a challenging task in many computer vision applications. In this paper, we propose a robust background modelling method for this task. First, the background is updated by an adaptive strategy based on Centre-symmetric Local Binary Patterns. Then, background subtraction is used for detecting moving object. Although the traditional background subtraction technique uses the difference value between the current pixel and its corresponding background pixel for objection detection, our method utilises the confidence factor to determine whether the current pixel is a background or foreground pixel. The confidence factor of the current pixel is calculated in term of the difference values of its neighbourhood pixels. In the experiments, the proposed algorithm is tested on several challenging datasets such as PETS 2009, BMC 2012 and SABS. The experimental results demonstrate that our algorithm can robustly detect moving object under various scenes. 相似文献
28.
29.
跨领域文本情感分类已成为自然语言处理领域的一个研究热点。针对传统主动学习不能利用领域间的相关信息以及词袋模型不能过滤与情感分类无关的词语,提出了一种基于逐步优化分类模型的跨领域文本情感分类方法。首先选择源领域和目标领域的公共情感词作为特征,在源领域上训练分类模型,再对目标领域进行初始类别标注,选择高置信度的文本作为分类模型的初始种子样本。为了加快目标领域的分类模型的优化速度,在每次迭代时,选取低置信度的文本供专家标注,将标注的结果与高置信度文本共同加入训练集,再根据情感词典、评价词搭配抽取规则以及辅助特征词从训练集中动态抽取特征集。实验结果表明,该方法不仅有效地改善了跨领域情感分类效果,而且在一定程度上降低了人工标注样本的代价。 相似文献
30.
Given two permutations of n elements, a pair of intervals of these permutations consisting of the same set of elements is called a common
interval . Some genetic algorithms based on such common intervals have been proposed for sequencing problems and have exhibited good
prospects. In this paper we propose three types of fast algorithms to enumerate all common intervals: (i) a simple O(n
2
) time algorithm (LHP), whose expected running time becomes O(n) for two randomly generated permutations, (ii) a practically fast O(n
2
) time algorithm (MNG) using the reverse Monge property, and (iii) an O(n+K) time algorithm (RC), where K
is the number of common intervals. It will also be shown that the expected number of common intervals for two random permutations
is O(1) . This result gives a reason for the phenomenon that the expected time complexity O(n) of the algorithm LHP is independent of K . Among the proposed algorithms, RC is most desirable from the theoretical point of view; however, it is quite complicated
compared with LHP and MNG. Therefore, it is possible that RC is slower than the other two algorithms in some cases. For this
reason, computational experiments for various types of problems with up to n=10
6
are conducted. The results indicate that (i) LHP and MNG are much faster than RC for two randomly generated permutations,
and (ii) MNG is rather slower than LHP for random inputs; however, there are cases in which LHP requires Ω(n
2
) time, but MNG runs in o(n
2
) time and is faster than both LHP and RC.
Received December 21, 1996; revised June 2, 1998. 相似文献