全文获取类型
收费全文 | 2222篇 |
免费 | 316篇 |
国内免费 | 216篇 |
专业分类
电工技术 | 59篇 |
综合类 | 369篇 |
化学工业 | 82篇 |
金属工艺 | 61篇 |
机械仪表 | 105篇 |
建筑科学 | 692篇 |
矿业工程 | 59篇 |
能源动力 | 31篇 |
轻工业 | 6篇 |
水利工程 | 35篇 |
石油天然气 | 2篇 |
武器工业 | 1篇 |
无线电 | 78篇 |
一般工业技术 | 337篇 |
冶金工业 | 30篇 |
原子能技术 | 3篇 |
自动化技术 | 804篇 |
出版年
2024年 | 5篇 |
2023年 | 55篇 |
2022年 | 103篇 |
2021年 | 82篇 |
2020年 | 80篇 |
2019年 | 65篇 |
2018年 | 55篇 |
2017年 | 57篇 |
2016年 | 110篇 |
2015年 | 83篇 |
2014年 | 127篇 |
2013年 | 167篇 |
2012年 | 244篇 |
2011年 | 223篇 |
2010年 | 194篇 |
2009年 | 208篇 |
2008年 | 188篇 |
2007年 | 214篇 |
2006年 | 207篇 |
2005年 | 64篇 |
2004年 | 30篇 |
2003年 | 23篇 |
2002年 | 20篇 |
2001年 | 19篇 |
2000年 | 16篇 |
1999年 | 23篇 |
1998年 | 4篇 |
1997年 | 7篇 |
1996年 | 7篇 |
1995年 | 5篇 |
1994年 | 9篇 |
1993年 | 8篇 |
1992年 | 4篇 |
1990年 | 8篇 |
1989年 | 2篇 |
1988年 | 3篇 |
1987年 | 15篇 |
1986年 | 11篇 |
1985年 | 3篇 |
1979年 | 6篇 |
排序方式: 共有2754条查询结果,搜索用时 46 毫秒
71.
College-enterprise cooperation model is a new model of cultivating application-typed talents in college by cooperating with enterprises.This thesis puts forward a set of quality assurance and evaluation mechanism,practice shows that this mechanism can effectively guarantee the teaching quality and evaluate the teaching results scientifically. 相似文献
72.
To meet for the enterprise requirements of software engineers and to solve the problems that the software engineers with low capacity in engineering and innovation issues at present,this paper first analyzes the software engineering education objectives and methods,then proposes to build an engineering teaching architecture which called One Frame with Four Aspects.This architecture reforms the practical teaching experience from educational concepts,practical training links,practical training objectives as well as practical training evaluation mechanism,especially focuses on the content of practice teaching,engineering teaching curriculum,the school-enterprise cooperation model and evaluation mechanisms.Practice has shown that the practical teaching system can be applied to software training well in Software School and its training effect is remarkable. 相似文献
73.
Partner selection is a major issue in the formation of a virtual enterprise. In practice, in the partner selection process, the information about the candidates and their performances are incomplete and uncertain. Vague sets theory is one of the methods used to deal with uncertain information. In this paper, a new method based on vague sets is proposed to deal with the partner selection problem in the formation of a virtual enterprise while the factors of satisfaction degree, due date, cost and the precedence of tasks are taken into account. On the basis of the agreement index of satisfaction degree, the formulated partner selection problems are interpreted so as to maximize the minimum agreement index. To solve the problem, an improved particle swarm optimization (PSO) algorithm is proposed. Finally, the simulation of a numerical example demonstrates that the method is effective. 相似文献
74.
75.
针对无线传感器网络节点负载不均衡的问题,提出了一种应用相对变换的无线传感器网络分簇算法(RTCH)。在成簇阶段,节点将簇头剩余能量、簇头与节点和簇头与基站的传输能耗等参数利用该模型先进行相对变换,再计算簇头适宜度来选择加入簇头成簇,并通过簇头的反馈信息来控制簇的规模来优化网络性能。仿真实验结果表明,RTCH算法能更有效地均衡网络中的能量消耗,延长网络生命周期。 相似文献
76.
The wavelet scaling functions of spline wavelets are used to construct the displacement interpolation functions of triangular
and rectangular thin plate elements. The displacement shape functions are then expressed by spline wavelet functions. A spline
wavelet finite element formulation of thin plate bending is developed by using the virtual work principle. Two numerical examples
have shown that the bending deflections and moments of thin plates agree well with those obtained by the differential equations
and conventional elements. It is demonstrated that the current spline wavelet finite element method (FEM) can achieve a high
numerical accuracy and converges fast. The proposed spline wavelet finite element formulation has a wide range of applicability
since it is developed in the same way like conventional displacement-based FEM. 相似文献
77.
Single multiplicative neuron model is a novel neural network model introduced recently, which has been used for time series prediction and function approximation. The model is based on a polynomial architecture that is the product of linear functions in different dimensions of the space. Particle swarm optimization (PSO), a global optimization method, is proposed to train the single neuron model in this paper. An improved version of the original PSO, cooperative random learning particle swarm optimization (CRPSO), is put forward to enhance the performance of the conventional PSO. The proposed CRPSO, PSO, back-propagation algorithm and genetic algorithm are employed to train the model for three well-known time series prediction problems. The experimental results demonstrate the superiority of CRPSO-based neuron model in efficiency and robustness over the other three algorithms. 相似文献
78.
79.
80.
为了解决认知无线网络中的频谱分配问题,提出一种基于多种群进化与粒子群优化混合的频谱分配算法。它采用图论着色模型,首先使用遗传算法将多个种群进行独立进化,以提高种群的全局搜索能力;然后选出每个种群中的最优的个体作为粒子群优化的粒子,并通过控制每个粒子的初始速度方向来加快算法的收敛速度。最后以系统总收益最大化和用户间的公平性为优化目标与遗传算法和粒子群算法进行了对比实验,仿真结果表明,该算法在收敛速度、认知用户接入公平性和系统总收益3个方面的性能均优于遗传算法和粒子群算法。 相似文献