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1.
矿山数字化摄影测量系统的设计与实现   总被引:2,自引:0,他引:2  
本文主要阐述矿山数字化摄影测量的基本原理、方法、矿山数字化摄影系统的硬件配置及软件组成,扼要介绍了系统所采用的算法及相关技术。  相似文献   
2.
为了及时撑握尾矿坝坑空间的变化,利用地理信息系统(GIS)的原理,使用Delaunay三角网的算法,结合VC和OPENGL设计应用程序,时尾矿坝进行测量并进行数据处理,由此生成尾矿坝的三维实体模型DTM,通过对其进行空间分析,为尾矿坝的监控和综合治理提供了科学依据.所设计的程序的运行速度快,精度高,可靠性好.  相似文献   
3.
利用ArcGIS三维构面的特性,形象的构建地表、河道现状立体模型,同时根据场地、河道的设计标高,构建立体模型,然后选定统一参考面,计算两个模型到参考面的体积之差,可以快捷、准确地计算出挖填土方量。实践证明,这一算法较传统的根据等高线、高程点计算土方量的方法更加严密、准确、便捷。同时这一方法能根据要求灵活调整、分割土方计算区域,不需要对调整后的边界进行外业高程点数据处理就能快速实现分区域土方量计算。  相似文献   
4.
基于Timoshenko梁理论研究弹性地基上转动功能梯度材料(FGM)梁的自由振动。首先确定功能梯度材料Timoshenko梁的物理中面,利用广义Hamilton原理推导出该梁在弹性地基上转动时横向自由振动的两个控制微分方程。其次采用微分变换法(DTM)对控制微分方程及其边界条件进行变换,计算了弹性地基上转动功能梯度材料Timoshenko梁在夹紧-夹紧、夹紧-简支和夹紧-自由三种不同边界条件下横向自由振动的量纲一固有频率,与已有文献的计算结果进行比较,退化后结果一致。最后讨论了不同边界条件、转速、弹性地基模量和梯度指数对功能梯度材料Timoshenko梁自振频率的影响。结果表明:功能梯度材料Timoshenko梁的量纲一固有频率随量纲一转速和量纲一弹性地基模量的增大而增大;在量纲一转速和量纲一弹性地基模量一定的情况下,梁的量纲一固有频率随着功能梯度材料梯度指数的增大而减小。  相似文献   
5.
An analysis is carried out for the flow of an unsteady electrically conducting liquid film on a horizontal stretching surface embedded with porous medium. In addition, a uniform heat source is taken care of in the present problem to model the governing equations of momentum and thermal energy to enhance the thermal properties of the considered fluid. Similarity variable as well as transformations are used to transform these equations into nondimensional. Solutions of these transformed ordinary differential equations are obtained using approximate analytical method, such as differential transformation method, and their refinement is verified by Pade approximant. The methodology of the analytical approach is presented clearly. Further, for validation, the numerical solutions are obtained and compared with the present analytical solution. The characteristics of the exhibiting parameters are shown via graphs and then discussed.  相似文献   
6.
In this study, fin efficiency of convective straight fins with temperature-dependent thermal conductivity is solved using a simulation method called the Differential Transformation Method (DTM). The concept of differential transformation is briefly introduced, and then we employed it to derive solutions of nonlinear equation. The obtained results from DTM are compared with those from the exact and numerical solution to verify the accuracy of the proposed method. The results reveal that the Differential Transformation Method can achieve suitable results in predicting the solution of such problems. After this verification, we analyze the effects of some physical applicable parameters in this problem such as thermo-geometric fin parameter and thermal conductivity parameter.  相似文献   
7.
VC环境下多层次DEM的算法实现   总被引:1,自引:0,他引:1  
为了实现数字地面模型的多层次显示,设计了一种基于三角形折叠的LOD的快速算法,首先利用分块扩展算法建立DEM,然后设定高程阀值,用LOD算法进行模型的简化,该方法十分方便模型的简化和还原操作,最后调用OpenGL函数实现了模型的可视化.  相似文献   
8.
The present level of literature on the subject matter indicates that nothing is known on the heat transfer across the couple stress rheological fluid flowing over a vertical avenue with Robin (mixed) wall conditions. The obtained conservation equations of the model are solved through DTM (differential transform method) and RPM (regular perturbation method). The nondimensional parameters obtained are a couple stress parameter, Brinkman number, mixed convection parameter, and Biot number. The computations reveal that flow acceleration and thermal enhancement is induced with increasing mixed convection parameter and Brinkman number for symmetric and asymmetric conditions. Increasing couple stress parameters dwindle the velocity and temperature for symmetric and asymmetric cases. The large values of the mixed convection parameter and Brinkman number increase the Nusselt values at the left wall and reduces at the right wall. The mass flow rate is augmented with the mixed convection parameter and Brinkman number but it is reduced with the couple stress parameter. The DTM, RKSM, and RPM solutions are in good agreement.  相似文献   
9.
基于“液阻理论”和“产品设计方法学”的座阀控制结构的分析是正确应用和进行座阀产品创新和基础。本文简略介绍了一些基本概念。  相似文献   
10.
Towards a Drought Watch System based on Spatial SPI   总被引:14,自引:10,他引:4  
Regional Drought can be assessed through various meaningfulprocedures mainly related to the expected consequences. However, a general knowledge of the occurrence of drought, thearea which is affected, its severity and its duration are ofgreat importance for a series of decisions, which may beappropriate for a variety of activities. From the existingsimple and popular indices used for the estimation of drought,the Standardised Precipitation Index, known as SPI, seems to winuniversal applicability. A method based on the estimation of SPIover a geographical area and its use for characterising drought,is presented in this paper. Applications of the method arepresented using a digital terrain model and a simple computercalculating routine. It is shown that the proposed procedurecan be easily applied and can support a Drought Watch System foran area of mesoscale dimensions.  相似文献   
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