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991.
We consider the totally real cyclic quintic fields , generated by a root of the polynomial
Assuming that is square free, we compute explicitly an integral basis and a set of fundamental units of and prove that has a power integral basis only for . For (both values presenting the same field) all generators of power integral bases are computed.
992.
A technique is presented to calculate the probability density function (pdf) for a sum of random variables that have pdf's on a logarithmic scale. In mobile radio it is often necessary to calculate the pdf of the total received signal power, which is the power sum of a number of simultaneously received signal powers. When the signal powers are given on a linear scale (e.g. Watts) probability density functions (pdf's) of the individual signals can be convolved to give the pdf for the received power of all the signals together. When, as is usual, the signal powers are given on a logarithmic scale (e.g. dBs) this is not possible. The simple convolution for the linear domain must now be replaced by a convolution for the logarithmic domain, which is not straightforward to compute. In this paper, a method is presented to compute the pdf of a power sum of two random variables, the logarithmic convolution. The results are not in closed form, numerical integration is necessary to find the resulting pdf. The method can be applied recursively to give results for power sums of more than two random variables. Although methods exist that give solutions in a closed form, they mainly use approximations and are valid only for specific distributions. The method presented in this paper yields exact results for arbitrary distributions. The results of the logarithmic convolution are verified by Monte-Carlo simulations. Even for large numbers of random variables the power sum results are shown to be correct. 相似文献
993.
In this study, new multiplier and adder method designs with multiplexers are proposed. The designs are based on quaternary logic and a carbon nanotube field-effect transistor (CNTFET). The design utilizes 4 × 4 multiplier blocks. Applying specific rotational functions and unary operators to the quaternary logic reduced the power delay produced (PDP) circuit by 54% and 17.5% in the CNTFETs used in the adder block and by 98.4% and 43.62% in the transistors in the multiplier block, respectively. The proposed 4 × 4 multiplier also reduced the occupied area by 66.05% and increased the speed circuit by 55.59%. The proposed designs are simulated using HSPICE software and 32 nm technology in the Stanford Compact SPICE model for CNTFETs. The simulated results display a significant improvement in the fabrication, average power consumption, speed, and PDP compared to the current best-performing techniques in the literature. The proposed operators and circuits are evaluated under various operating conditions, and the results demonstrate the stability of the proposed circuits. 相似文献
994.
为克服传统电力电子实验平台不能满足高阶、创新实验教学要求的缺点,采用HIL技术设计了电力电子教学平台,改革电力电子技术课程的实验教学,构建了验证性实验、设计性实验和创新性综合训练3 个层次,培养学生的掌握电能变换电路的分析与设计方法,提升学生的解决复杂工程能力和创新思维。所设计的实验平台不需要传统HIL技术中高速采集卡和I/O接口板,采用串口通讯实现物理部分和仿真部分之间的数据交换,虽然会增加一些时间消耗,但极大地降低了实验平台的建设和运维成本,更适合本科实验教学。 相似文献
995.
996.
Prasenjit Chanak Indrajit Banerjee R. Simon Sherratt 《International Journal of Communication Systems》2020,33(9)
In wireless sensor networks (WSNs), clustering has been shown to be an efficient technique to improve scalability and network lifetime. In clustered networks, clustering creates unequal load distribution among cluster heads (CHs) and cluster member (CM) nodes. As a result, the entire network is subject to premature death because of the deficient active nodes within the network. In this paper, we present clustering‐based routing algorithms that can balance out the trade‐off between load distribution and network lifetime “green cluster‐based routing scheme.” This paper proposes a new energy‐aware green cluster‐based routing algorithm to preventing premature death of large‐scale dense WSNs. To deal with the uncertainty present in network information, a fuzzy rule‐based node classification model is proposed for clustering. Its primary benefits are flexibility in selecting effective CHs, reliability in distributing CHs overload among the other nodes, and reducing communication overhead and cluster formation time in highly dense areas. In addition, we propose a routing scheme that balances the load among sensors. The proposed scheme is evaluated through simulations to compare our scheme with the existing algorithms available in the literature. The numerical results show the relevance and improved efficiency of our scheme. 相似文献
997.
The Mobile Adhoc Network (MANET) is a distributed network without any standard infrastructure. In MANETs, several nodes in the network are grouped by which they can communicate with each other. Clustering is a grouping of mobiles nodes performs the communication process by means of optimal usage of available bandwidth and high network throughput. Several clustering schemes exist, but they suffer from the consumption of energy because of the cluster head's workload and increase in the number of clusters. In this paper, we propose a cluster manager‐based cluster head selection (CMBCH) scheme to overcome the energy problems and leverage CH workload. CMBCH consists of two components, such as cluster manager (CM) and cluster head (CH). The CM takes the responsibility of controlling and monitoring of nodes activities. The CH leads and performing packet transfer among the nodes in the network. At this stage, when current CH energy level is drained, CM elects the corresponding node with high energy level and the new, as well as old CH activities, are simultaneously stored by CM. To prove the proposed scheme efficiency, a simulation experiment was conducted for 20 to 100 nodes under the AODV routing protocol. The network parameters packet delivery ratio and energy consumption are compared for the CMBCH,DLC and HCAL. The obtained results are compared to others; CMBCH conserves minimal energy and bandwidth and also achieves reliable throughput through stable routing. 相似文献
998.
本文主要介绍了湖北某水泥厂能耗在线监测企业端系统的研究与方案设计,论述了设计依据、标准、实用、经济的信息化管理系统,并对其数据传输规则、网络结构、软件功能架构、系统实施等进行了重点阐述。 相似文献
999.
This paper presents a number of power grid network design and optimization techniques that consider the electromigration (EM) effects for multi-segment interconnect wires. First, we consider a new EM immortality constraint due to EM void saturation volume for multi-segment interconnects. It helps reduce conservativeness in the EM-aware on-chip power grid design. Along with the EM nucleation phase immortality constraint, we show that both EM immortality constraints can be naturally integrated into the existing programming based power grid optimization framework. Second, to mitigate the overly conservativeness of the immortality constrained optimization methods, we further explore three strategies: we first size up failed wires to meet one of the immortality conditions subject to the design rules; second, we consider the EM-induced aging effects on power supply networks for a target lifetime, which allows some short-lived wires to fail and optimizes the remaining wires; third, we propose a large change sensitivity-based optimization scheme to perform localized fixing based on recently proposed coupled EM-IR drop analysis method. Numerical results on a number of IBM-format power grid networks demonstrate that the new method can reduce more power grid area compared to the existing EM immortality constrained optimizations. Moreover, the new method is able to optimize power grids with nucleated wires, which would not be possible with the existing methods. Results also show the sensitivity-based localized power girds fixing can fix EM-induced IR drop violations in a few minutes for synthesized power grid networks from ARM core designs. 相似文献
1000.
本文对基于蓝牙5.2规范的新一代低功耗蓝牙音频技术标准LE Audio及其关键技术特点进行了浅析。 相似文献