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91.
提出并实现了一种从单目视频流中重建人体三维运动的方法.该方法通过交互定制得到个性化的人体骨架模型和视频序列每一帧中人体各关节点的二维坐标后,分别针对单帧和连续多帧进行优化并迭代求解,得到每一帧的比例因子的最优解;最后反求各关节点的三维坐标,重建人体三维运动序列.对包含复杂和快速多变的人体运动的视频进行的实验表明,该方法简单有效,适用于包括体育、影视等在内的实际视频源. 相似文献
92.
差异压实作用中的同沉积小断层成因探讨——以高台子地区扶杨油层为例 总被引:2,自引:1,他引:1
入湖三角洲不同于入海三角洲,重力作用很难造成沉积物大幅度滑动,故同生断层与伴生背斜并不发育.前人做等时地层格架剖面对比前优选骨架井时,已尽量避开目的层断缺井,故对比分析地层厚度变化时更多的从沉积成因分析,不再考虑断层影响.高台子地区扶杨油层低砂泥比,高钙质砂岩含量为差异压实作用的形成提供了条件.由于砂泥岩间差异压实作用和砂、泥岩结合部位薄弱环节的普遍存在,高台子地区扶杨油层沉积期断续分布的叠合透镜状砂体本身为形成小幅度差异压实构造准备了雏型,其边缘也是同生小正断层形成的应力集中部位.从而围绕透镜状砂体形成了较多小型同生正断层.可用于解释类似相域等时旋回厚度的不协调变化. 相似文献
93.
94.
混合型裂纹断裂能(GF)是裂纹扩展的判据之一,是裂纹扩展方向分析的基础。以往平面问题断裂能J积分方法的研究只是局限于Ⅰ型或是Ⅱ型,裂纹方向为水平方向。推导了Ⅰ-Ⅱ混合型裂纹任意角度时线弹性材料J积分与应力强度因子(SIF)K之间的关系,提出将比例边界有限元法(SBFEM)用于J积分的求解。在数值计算中,通过用SBFEM、有限元法(FEM)和用推导公式计算J积分的对比,验证推导公式的正确性,同时也说明SBFEM计算J积分是精确的、方便的。根据数值计算的结果,对计算边界与裂纹的距离、计算单元的尺寸以及积分路径等诸因素对精度的影响进行一定分析。 相似文献
95.
Z. J. Yang A. J. Deeks H. Hao 《International journal for numerical methods in engineering》2007,70(12):1387-1408
The scaled boundary finite element method (FEM) is a recently developed semi‐analytical numerical approach combining advantages of the FEM and the boundary element method. Although for elastostatics, the governing homogeneous differential equations in the radial co‐ordinate can be solved analytically without much effort, an analytical solution to the non‐homogeneous differential equations in frequency domain for elastodynamics has so far only been obtained by a rather tedious series‐expansion procedure. This paper develops a much simpler procedure to obtain such an analytical solution by increasing the number of power series in the solution until the required accuracy is achieved. The procedure is applied to an extensive study of the steady‐state frequency response of a square plate subjected to harmonic excitation. Comparison of the results with those obtained using ABAQUS shows that the new method is as accurate as a detailed finite element model in calculating steady‐state responses for a wide range of frequencies using only a fraction of the degrees of freedom required in the latter. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
96.
A proposed interview procedure has ratings based on scaled examples of on-the-job behavior. Traits necessary were determined, and examples were written of behaviors related to these traits. Examples were checked for agreement as to trait category, and scaled as to degree of the trait exhibited. Interviewers rated each candidate by making analogies from the candidate's responses to job behavior that might be expected of the candidate. Interviews using 3 raters to judge 1 candidate simultaneously and using 2 different interviewers to judge the same candidate 1 at a time, indicate the technique's high reliability. Interrater reliability was significantly higher (p 相似文献
97.
98.
In order to study dynamic response of a stay cable of cable-stayed bridges under blast loading, based on the basic blast theory, the anti-explosion performance of the cable under near field blast loading was analyzed.Stress and damage of the cable were analyzed, and further the parametric analyses for different scaled distances were performed.Results showed that under near field blast load, fracture does not appear on the cable, and its failure mode presents a failure caused by its stress exceeding yield one;its weakest position is the cable-girder anchorage zone where the stress of the cable is larger than that of the cable near explosion point due to reflection of blast wave; the safe scaled distance to keep the cable from failure is 0.287 m/kg1/3,if the scaled distance is larger than this critical scaled distance, the cable can’t fail. 相似文献
99.
技术的发展要求超大规模集成电路的特征尺寸进一步降低以提高元件密度,这就需要低介电常数(k)的多孔电介质的应用.而多孔介质的输运物理性质通常与其微结构有密切关系.本文在综述多孔电介质利用分形模型分析方法的基础上,利用分形几何理论,进一步把多孔电介质介电常数(k)与反映孔微结构的分形维数联系起来,更好地适应于实际中不均一不规则的多孔电介质介电常数的分析计算. 相似文献
100.
Masoud Fatemi 《Optimization methods & software》2017,32(5):1095-1112
We propose a new optimization problem which combines the good features of the classical conjugate gradient method using some penalty parameter, and then, solve it to introduce a new scaled conjugate gradient method for solving unconstrained problems. The method reduces to the classical conjugate gradient algorithm under common assumptions, and inherits its good properties. We prove the global convergence of the method using suitable conditions. Numerical results show that the new method is efficient and robust. 相似文献