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181.
天和家园43kWp屋顶并网光伏发电系统设计 总被引:3,自引:0,他引:3
介绍了浙江省慈溪市天和家园住宅小区43kWp屋顶太阳能并网光伏发电系统的设计思路,以及系统的具体功能与配置,提出了设计中需要注意的问题及具体的解决方案。包括:①光伏系统提供公用设施用电,在阴雨天时使用城市电网为公用负荷供电;②光伏系统在小区内局部并网,不考虑将电能输入上级城市电网;③太阳能电池组件方阵倾角确定为30°,选用常州天合光能有限公司生产的TSM-175D型高效单晶硅电池组件,分析了组件分组串接原则,确定了布置方案;④并网逆变器选择德国艾思玛(SMA)公司的SMC6000TL型无变压器集中式逆变器和SB5000TL型无变压器多组串逆变器;⑤地下车库照明负荷曲线与日照曲线接近,因此选择地下车库照明和智能化设备用电为光伏系统负荷;⑥简介了防直击雷和防感应雷措施,以及选择电缆和设计支架时应考虑的因素;⑦监控系统选用SMA的Sunny Boy ControlPlus产品。 相似文献
182.
Max Halperin 《技术计量学》2013,55(3):295-305
A mildly conservative but very rapid calculation technique is proposed for problems requiring the use of the Non-central t distribution. Examples and a brief table are provided. 相似文献
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We present a novel, real-time algorithm for computing the continuous penetration depth (CPD) between two interpenetrating rigid models bounded by triangle meshes. Our algorithm guarantees gradient continuity for the penetration depth (PD) results, unlike conventional penetration depth (PD) algorithms that may have directional discontinuity due to the Euclidean projection operator involved with PD computation. Moreover, unlike prior CPD algorithms, our algorithm is able to handle an orientation change in the underlying model and deal with a topologically-complicated model with holes. Given two intersecting models, we interpolate tangent planes continuously on the boundary of the Minkowski sums between the models and find the closest point on the boundary using Phong projection. Given the high complexity of computing the Minkowski sums for polygonal models in 3D, our algorithm estimates a solution subspace for CPD and dynamically constructs and updates the Minkowski sums only locally in the subspace. We implemented our algorithm on a standard PC platform and tested its performance in terms of speed and continuity using various benchmarks of complicated rigid models, and demonstrated that our algorithm can compute CPD for general polygonal models consisting of tens of thousands of triangles with a hole in a few milli-seconds while guaranteeing the continuity of PD gradient. Moreover, our algorithm can compute more optimal PD values than a state-of-the-art PD algorithm due to the dynamic Minkowski sum computation. 相似文献
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Supply chain formation is the process by which a set of producers within a network determine the subset of these producers able to form a chain to supply goods to one or more consumers at the lowest cost. This problem has been tackled in a number of ways, including auctions, negotiations, and argumentation‐based approaches. In this paper we show how this problem can be cast as an optimization of a pairwise cost function. Optimizing this class of energy functions is NP‐hard but efficient approximations to the global minimum can be obtained using loopy belief propagation (LBP). Here we detail a max‐sum LBP‐based approach to the supply chain formation problem, involving decentralized message‐passing between supply chain participants. Our approach is evaluated against a well‐known decentralized double‐auction method and an optimal centralized technique, showing several improvements on the auction method: it obtains better solutions for most network instances which allow for competitive equilibrium (Competitive equilibrium in Walsh and Wellman is a set of producer costs which permits a Pareto optimal state in which agents in the allocation receive non‐negative surplus and agents not in the allocation would acquire non‐positive surplus by participating in the supply chain) while also optimally solving problems where no competitive equilibrium exists, for which the double‐auction method frequently produces inefficient solutions. 相似文献
188.
In the automotive sector, the cumulative damage calculation method generally applied is the Palmgren–Miner-Hypothesis with its modification according to Haibach (steeper slope of the SN-line after the knee-point) as a means of also including the damage by stress amplitudes below the knee-point. This approach results in the total damage sum of the spectrum Dspec. However, the resulting question is the value of the allowable damage sum Dal for the evaluation of Dspec ⩽ Dal. The only design code that considers the assessment of cast iron components under spectrum loading is the FKM-Guideline of the Cooperative Research Association for Mechanical Engineering (FKM, Frankfurt/Germany) for designing machine components. Here, the theoretical Palmgren–Miner-damage sum Dth = 1.0 is still suggested as the allowable damage sum Dal despite the fact that this damage sum renders unsafe calculated fatigue lives in about 90% of all published results.The results obtained with component-like notched specimens of modern high-strength cast iron alloys (Rm = 650–800 MPa) such as EN-GJS-500-7, SiboDur 700-10 and MADI (Machinable Austempered Ductile Iron), which were investigated under a standard Gaussian spectrum for chassis applications and also for a fuller injection pump spectrum, suggest the allowable damage sum Dal = 0.3 for fatigue life estimations of components manufactured with these materials can be proposed; i.e. the allowable fatigue life is about one third compared to calculations with the theoretical damage sum Dth = 1.0 that is still used. 相似文献
189.
F. Lombard 《技术计量学》2013,55(3):305-310
The cumulative sum (CUSUM) is a basic diagnostic tool in the analysis of change-point data. It is shown that Fourier analysis of the CUSUM can be a useful supplementary tool in such analyses. The technique is applied to three data sets that have appeared previously in the statistical literature. 相似文献
190.
This article is concerned with the polynomial filtering problem for a class of nonlinear stochastic systems governed by the Itô differential equation. The system under investigation involves polynomial nonlinearities, unknown‐but‐bounded disturbances, and state‐ and disturbance‐dependent noises ((x,d)‐dependent noises for short). By expanding the polynomial nonlinear functions in Taylor series around the state estimate, a new polynomial filter design method is developed with hope to reduce the conservatism of the existing results. In virtue of stochastic analysis and inequality technique, sufficient conditions in terms of parameter‐dependent linear matrix inequalities (PDLMIs) are derived to guarantee that the estimation error system is input‐to‐state stable in probability. Moreover, the desired polynomial matrix can be obtained by solving the PDLMIs via the sum‐of‐squares approach. The effectiveness and applicability of the proposed method are illustrated by two numerical examples with one concerning the permanent magnet synchronous motor. 相似文献