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51.
3D human pose estimation in motion is a hot research direction in the field of computer vision. However, the performance of the algorithm is affected by the complexity of 3D spatial information, self-occlusion of human body, mapping uncertainty and other problems. In this paper, we propose a 3D human joint localization method based on multi-stage regression depth network and 2D to 3D point mapping algorithm. First of all, we use a single RGB image as the input, through the introduction of heatmap and multi-stage regression to constantly optimize the coordinates of human joint points. Then we input the 2D joint points into the mapping network for calculation, and get the coordinates of 3D human body joint points, and then to complete the 3D human body pose estimation task. The MPJPE of the algorithm in Human3.6 M dataset is 40.7. The evaluation of dataset shows that our method has obvious advantages.  相似文献   
52.
Human–Robot Collaboration (HRC) is a term used to describe tasks in which robots and humans work together to achieve a goal. Unlike traditional industrial robots, collaborative robots need to be adaptive; able to alter their approach to better suit the situation and the needs of the human partner. As traditional programming techniques can struggle with the complexity required, an emerging approach is to learn a skill by observing human demonstration and imitating the motions; commonly known as Learning from Demonstration (LfD). In this work, we present a LfD methodology that combines an ensemble machine learning algorithm (i.e. Random Forest (RF)) with stochastic regression, using haptic information captured from human demonstration. The capabilities of the proposed method are evaluated using two collaborative tasks; co-manipulation of an object (where the human provides the guidance but the robot handles the objects weight) and collaborative assembly of simple interlocking parts. The proposed method is shown to be capable of imitation learning; interpreting human actions and producing equivalent robot motion across a diverse range of initial and final conditions. After verifying that ensemble machine learning can be utilised for real robotics problems, we propose a further extension utilising Weighted Random Forest (WRF) that attaches weights to each tree based on its performance. It is then shown that the WRF approach outperforms RF in HRC tasks.  相似文献   
53.
介绍了避雷器三极法测量接地电阻的接线、测量原理及测量电压的选取,根据测得的历史数据建立了基于回归分析的接地电阻变化趋势预测模型,并通过标准离差检验证明了该预测模型可用于实际接地电阻的预测。实践表明,该测量与预测方法切实可行,能在一定程度上避免因接地电阻超标而引发的雷击事故。  相似文献   
54.
肖应旺 《控制工程》2012,19(2):301-306
针对化工精馏过程产品成分无法在线检测及其用温度间接控制产品成分的常规控制策略存在着控制精度低的问题,提出基于软测量的精馏过程成分非线性串级推断控制策略。该控制策略首先提出核岭回归的实时软测量方法,即利用满足Mercer条件的核函数改进线性岭回归算法,实现精馏过程产品成分的在线检测;然后在此基础上,提出一种新的非线性串级推断控制策略,即副环采用常规的温度间接控制,主环采用基于核岭回归软测量的推断控制策略。通过Mejedell等建立的精馏塔动态模型分别对单端和双端成分非线性串级推断控制策略性能进行分析,仿真结果表明,与传统控制方案比较,新控制策略的控制质量有了较大提高,控制结构简单,易于实施。  相似文献   
55.
In the areas of investment research and applications, feasible quantitative models include methodologies stemming from soft computing for prediction of financial time series, multi-objective optimization of investment return and risk reduction, as well as selection of investment instruments for portfolio management based on asset ranking using a variety of input variables and historical data, etc. Among all these, stock selection has long been identified as a challenging and important task. This line of research is highly contingent upon reliable stock ranking for successful portfolio construction. Recent advances in machine learning and data mining are leading to significant opportunities to solve these problems more effectively. In this study, we aim at developing a methodology for effective stock selection using support vector regression (SVR) as well as genetic algorithms (GAs). We first employ the SVR method to generate surrogates for actual stock returns that in turn serve to provide reliable rankings of stocks. Top-ranked stocks can thus be selected to form a portfolio. On top of this model, the GA is employed for the optimization of model parameters, and feature selection to acquire optimal subsets of input variables to the SVR model. We will show that the investment returns provided by our proposed methodology significantly outperform the benchmark. Based upon these promising results, we expect this hybrid GA-SVR methodology to advance the research in soft computing for finance and provide an effective solution to stock selection in practice.  相似文献   
56.
依托吉林引松工程开展隧道掘进机(TBM)施工参数预测研究,提出TBM施工数据分段提取算法,提取上升段前30 s的总推进力、刀盘转速、推进速度、刀盘扭矩、刀盘转速电位器设定值、推进速度电位器设定值、贯入度、贯入度指数(FPI)、扭矩切深指数(TPI)9个参数作为输入;通过局部线性嵌入(LLE)完成对上升段数据特征的降维;基于支持向量机回归(SVR)建立TBM施工控制参数(推进速度、刀盘转速)和负载参数(总推进力、刀盘扭矩)预测模型. 分析是否结合前一掘进循环的FPI、TPI指数进行预测对预测效果的影响. 结果表明,上述方法在推进速度、刀盘转速、总推进力、刀盘扭矩的预测中均取得了较好的预测效果,平均预测绝对百分比误差均小于15%,验证了该预测方法的有效性,该方法可以为TBM现场施工提供指导.  相似文献   
57.
分析风电场之间的出力相关性有助于合理规划风机的功率输送以及调度优化,从而提高传输线路的利用率。以冀北地区风场为例,首先分析了该区域风速的分布特性,然后利用贝叶斯线性回归算法建立混合Copula函数模型,拟合得到4个机群风速序列的联合分布,计算出风电场之间的出力相关性,并与其他相关性函数建模进行对比研究。研究结果表明,基于贝叶斯线性回归的混合Copula函数模型能够提高参数估计的精确性,从而使得计算出的相关性更为准确,并且由其拟合得到的出力概率分布与实际风场出力的概率分布较为一致。  相似文献   
58.
The microstructures of Fe-Mn-Ni-Cr steels with medium carbon and the effect of alloy ele-ments on them have been investigated by means of X-ray diffraction quantitative phase ana-lyses,metallography and hardness tests.The volume fraction of martensite in steels quenchedat 1100℃ can be expressed as:f_M~(1100)=162.643-15.482Mn-7.36Ni-4.286(Cr+Mo+V)Based on this expression,the quasi-equilibrium microstructure diagram has been obtained.Itis shown that the effect of Mn on the austenite stability is greater than that of Ni.The equiva-lent [Ni]=2.104Mn+Ni and equivalent [Cr]=Cr+Mo+V.The driving force for martensite transformation at M_s point has been calculated to hedrastically decreased by element Mn.  相似文献   
59.
滚切剪剪切力的实验研究   总被引:1,自引:0,他引:1  
对直导向滚切剪的剪切力进行了实验研究,得到了计算最大剪切力的经验公式。  相似文献   
60.
In this paper, a hybrid intelligent system that consists of the Fuzzy Min–Max neural network, the Classification and Regression Tree, and the Random Forest model is proposed, and its efficacy as a decision support tool for medical data classification is examined. The hybrid intelligent system aims to exploit the advantages of the constituent models and, at the same time, alleviate their limitations. It is able to learn incrementally from data samples (owing to Fuzzy Min–Max neural network), explain its predicted outputs (owing to the Classification and Regression Tree), and achieve high classification performances (owing to Random Forest). To evaluate the effectiveness of the hybrid intelligent system, three benchmark medical data sets, viz., Breast Cancer Wisconsin, Pima Indians Diabetes, and Liver Disorders from the UCI Repository of Machine Learning, are used for evaluation. A number of useful performance metrics in medical applications which include accuracy, sensitivity, specificity, as well as the area under the Receiver Operating Characteristic curve are computed. The results are analyzed and compared with those from other methods published in the literature. The experimental outcomes positively demonstrate that the hybrid intelligent system is effective in undertaking medical data classification tasks. More importantly, the hybrid intelligent system not only is able to produce good results but also to elucidate its knowledge base with a decision tree. As a result, domain users (i.e., medical practitioners) are able to comprehend the prediction given by the hybrid intelligent system; hence accepting its role as a useful medical decision support tool.  相似文献   
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