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801.
最小可觉差是人眼视觉重要特性之一,随着计算机显示器的普及,显示器环境下的亮度最小可觉差对图像细节有重要的应用价值。利用10bit图像显示卡和液晶显示器方便、精确控制亮度刺激,在显示器显示亮度范围内产生27个不同亮度背景,采样心理物理学亮度视觉匹配实验测得亮度最小可觉差。实验结果表明,在背景亮度为11.89~142.3cd/m~2中等亮度下人眼最小可觉差与背景亮度的比值约为0.017,并遵守韦伯定律;在背景亮度为0.38~9.36cd/m~2的弱亮度情况下,人眼最小可觉差与背景亮度的比值随亮度的增加呈单调递减趋势。在显示器上测量的中等亮度下人眼亮度最小可觉差与Koenig and Brodhun采用传统光学方法得到的实验结果基本一致。 相似文献
802.
本文首先对南宁东站综合交通枢纽一期(地下空间)--公共服务工程通信系统设备集成采购项目做一简单介绍,然后通过介绍南宁东站项目中通信标的几个典型子系统的系统组成原理进一步阐述通信系统在智能建筑中的应用。 相似文献
803.
In order to improve the system compatibility of the safety computer of the next generation train operation con-trol system, first of all, the structure was analyzed and the management mechanism was designed, the state transition model of management unit was established, and the correctness of the model was verified by formal verification tools at the same time. Then the software and hardware which based on micro controller unit (MCU) were designed and imple-mented. The verification and test results show that the management mechanism design meets the design requirements, the management unit can achieve the expected state transfer function. 相似文献
804.
随着科学技术的迅速发展以及工业化建设进程的不断加快,计算机技术在我国各行各业中得到了越来越广泛的应用。计算机在工业生产过程中的普遍应用,大力推动着其朝着现代化、集成化、网络化、自动化的方向发展。大数据时代下,计算机的应用推动了工业生产的发展,而现代工业生产的发展也使得计算机的应用更加广泛,工业生产与计算机的应用相互影响、互相促进,相得益彰。本篇论文主要对计算机在工业生产中的应用进行了分析与研究。 相似文献
805.
随着现今经济以及科学技术的快速发展,我国的计算机技术也得到了迅速的发展。在日常生活中,信息技术对于人们的生活产生极大的影响,如移动媒体的大范围使用等。从本质上来说,移动媒体属于远程网络通讯技术的一种,利用这种技术,可实现对社会上信息的实时共享。本文主要从目前的情况下对计算机远程网络通讯技术的应用进行了深入分析。 相似文献
806.
天气预报,主要是借助卫星等现代化设备,实现对气象信息的检测,通过相关软件和模式的分析,实现对未来天气的预知、探测和发布,以满足人们对气象信息的需要。气象部门在进行天气预报探测过程中,根据计算机技术的运行特点和高效管理,全面运用计算机技术,有利于实现对天气预报信息的科学监测和管理,以推动天气预报技术的全面发展。本文对应用计算机加强天气预报信息管理的作用进行探讨,以实现对天气预报信息管理的全面认识,结合计算机的相关技术,制定合理的应用策略,以提高天气预报信息管理的准确性和科学性,进而促进天气预报技术的发展。 相似文献
807.
Matching for a wavefunction the WKB expansion at large distances and Taylor expansion at small distances leads to a compact, few-parametric uniform approximation found in Turbiner and Olivares-Pilon (2011). The ten low-lying eigenstates of H2+ of the quantum numbers (n,m,Λ,±) with n=m=0 at Λ=0,1,2, with n=1, m=0 and n=0, m=1 at Λ=0 of both parities are explored for all interproton distances R. For all these states this approximation provides the relative accuracy ?10−5 (not less than 5 s.d.) locally, for any real coordinate x in eigenfunctions, when for total energy E(R) it gives 10-11 s.d. for R∈[0,50] a.u. Corrections to the approximation are evaluated in the specially-designed, convergent perturbation theory. Separation constants are found with not less than 8 s.d. The oscillator strength for the electric dipole transitions E1 is calculated with not less than 6 s.d. A dramatic dip in the E1 oscillator strength f1sσg−3pσu at R∼Req is observed. The magnetic dipole and electric quadrupole transitions are calculated for the first time with not less than 6 s.d. in oscillator strength. For two lowest states (0,0,0,±) (or, equivalently, 1sσg and 2pσu states) the potential curves are checked and confirmed in the Lagrange mesh method within 12 s.d. Based on them the Energy Gap between 1sσg and 2pσu potential curves is approximated with modified Pade Re−R[Pade(8/7)](R) with not less than 4-5 figures at R∈[0,40] a.u. Sum of potential curves E1sσg+E2pσu is approximated by Pade 1/R[Pade(5/8)](R) in R∈[0,40] a.u. with not less than 3-4 figures. 相似文献
808.
Fabio Boschetti 《Complexity》2016,21(6):202-213
Computer models can help humans gain insight into the functioning of complex systems. Used for training, they can also help gain insight into the cognitive processes humans use to understand these systems. By influencing humans understanding (and consequent actions) computer models can thus generate an impact on both these actors and the very systems they are designed to simulate. When these systems also include humans, a number of self‐referential relations thus emerge which can lead to very complex dynamics. This is particularly true when we explicitly acknowledge and model the existence of multiple conflicting representations of reality among different individuals. Given the increasing availability of computational devices, the use of computer models to support individual and shared decision making could potentially have implications far wider than the ones often discussed within the Information and Communication Technologies community in terms of computational power and network communication. We discuss some theoretical implications and describe some initial numerical simulations. © 2015 Wiley Periodicals, Inc. Complexity 21: 202–213, 2016 相似文献
809.
Seydou Traoré Kyle E. Roberts David Allouche Bruce R. Donald Isabelle André Thomas Schiex Sophie Barbe 《Journal of computational chemistry》2016,37(12):1048-1058
One of the main challenges in computational protein design (CPD) is the huge size of the protein sequence and conformational space that has to be computationally explored. Recently, we showed that state‐of‐the‐art combinatorial optimization technologies based on Cost Function Network (CFN) processing allow speeding up provable rigid backbone protein design methods by several orders of magnitudes. Building up on this, we improved and injected CFN technology into the well‐established CPD package Osprey to allow all Osprey CPD algorithms to benefit from associated speedups. Because Osprey fundamentally relies on the ability of to produce conformations in increasing order of energy, we defined new strategies combining CFN lower bounds, with new side‐chain positioning‐based branching scheme. Beyond the speedups obtained in the new ‐CFN combination, this novel branching scheme enables a much faster enumeration of suboptimal sequences, far beyond what is reachable without it. Together with the immediate and important speedups provided by CFN technology, these developments directly benefit to all the algorithms that previously relied on the DEE/ combination inside Osprey* and make it possible to solve larger CPD problems with provable algorithms. © 2016 Wiley Periodicals, Inc. 相似文献
810.
Grzegorz Mazur Marcin Makowski Roman Łazarski Radosław Włodarczyk Ewa Czajkowska Michał Glanowski 《International journal of quantum chemistry》2016,116(18):1370-1381
A unified, computer algebra system‐based scheme of code‐generation for computational quantum‐chemistry programs is presented. Generation of electron‐repulsion integrals and their derivatives as well as exchange‐correlation potential and its derivatives is discussed. Application to general‐purpose computing on graphics processing units is considered. 相似文献