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91.
Aging and imperfections provide important visual cues for realism. We present a novel physically‐based approach for simulating the biological aging and decay process in fruits. This method simulates interactions between multiple processes. Our biologically‐derived, reaction‐diffusion model generates growth patterns for areas of fungal and bacterial infection. Fungal colony spread and propagation is affected by both bacterial growth and nutrient depletion. This process changes the physical properties of the surface of the fruit as well as its internal volume substrate. The fruit is physically simulated with parameters such as skin thickness and porosity, water content, flesh rigidity, ambient temperature, humidity, and proximity to other surfaces. Our model produces a simulation that closely mirrors the progression of decay in real fruits under similar parameterized conditions. Additionally, we provide a tool that allows artists to customize the input of the program to produce generalized fruit simulations. 相似文献
92.
Joseph Shtargot 《电子技术应用》2011,37(1):19-21
阐述了MAX11046等同时采样ADC在电力线监测中的应用,介绍了交流电测量的基本原理,给出了电网监测的典型应用以及国际标准对监测系统的要求.归纳了MAX11046电力线监测的独特优势并提供了一个应用案例,介绍如何选择外围器件,优化系统性能. 相似文献
93.
This article presents a new method for the synthesis of an arbitrary spatial elastic behavior with an elastic mechanism. The mechanisms considered are parallel and serial mechanisms with concurrent axes. We show that any full‐rank spatial stiffness matrix can be realized using a parallel mechanism with all spring axes intersecting at a unique point. It is shown that this intersection point must be the center of stiffness. We also show that any full‐rank spatial compliance matrix can be realized using a serial mechanism with all joint axes intersecting at a unique point. This point is shown to be the center of compliance. Synthesis procedures for mechanisms with these properties are provided. The realizations are shown to be minimal in the sense that both the number of screw components and the total number of components are minimum. © 2001 John Wiley & Sons, Inc. 相似文献
94.
Usability engineering for augmented reality: employing user-based studies to inform design 总被引:1,自引:0,他引:1
A major challenge, and thus opportunity, in the field of human-computer interaction and specifically usability engineering is designing effective user interfaces for emerging technologies that have no established design guidelines or interaction metaphors or introduce completely new ways for users to perceive and interact with technology and the world around them. Clearly, augmented reality is one such emerging technology. We propose a usability engineering approach that employs user-based studies to inform design, by iteratively inserting a series of user-based studies into a traditional usability engineering lifecycle to better inform initial user interface designs. We present an exemplar user-based study conducted to gain insight into how users perceive text in outdoor augmented reality settings and to derive implications for design in outdoor augmented reality. We also describe lessons learned from our experiences conducting user-based studies as part of the design process. 相似文献
95.
Joseph A. Cazier Benjamin B. M. Shao Robert D. St. Louis 《Information Systems Frontiers》2007,9(5):515-529
This study explores how value congruence contributes to the formation of trust in e-businesses, and how trust and value congruence
influence consumers to share personal information. It is hypothesized that the perceived values of organizations regarding
moral, social, environmental and political causes can have an effect on the trusting beliefs of e-commerce consumers and their
willingness to disclose private personal information. A total of 775 subjects rated their perceived value congruence with
organizations, their trusting beliefs, and the types of information they would be willing to disclose. This study finds that
value congruence not only plays a role in mediating the trust of consumers for the organizations, but it also has a strong
effect on determining their willingness to disclose personal information. In some cases, the influence of value congruence
is greater than that of trust, even though trust has been touted in the literature as one of the most important factors in
e-commerce. This research expands prior work by using structural equation modeling to test the relative strength of the effect
of value congruence on each dimension of trust and the overall trust level, as well as its direct effect on behavioral intentions
in terms of information sharing for non-profit and for-profit organizations.
相似文献
Robert D. St. LouisEmail: |
96.
Bruno Juliá-Díaz Joseph M. Burdis Frank Tabakin 《Computer Physics Communications》2006,174(11):914-934
This Mathematica 5.2 package1 is a simulation of a Quantum Computer. The program provides a modular, instructive approach for generating the basic elements that make up a quantum circuit. The main emphasis is on using the density matrix, although an approach using state vectors is also implemented in the package. The package commands are defined in Qdensity.m which contains the tools needed in quantum circuits, e.g., multiqubit kets, projectors, gates, etc. Selected examples of the basic commands are presented here and a tutorial notebook, Tutorial.nb is provided with the package (available on our website) that serves as a full guide to the package. Finally, application is made to a variety of relevant cases, including Teleportation, Quantum Fourier transform, Grover's search and Shor's algorithm, in separate notebooks: QFT.nb, Teleportation.nb, Grover.nb and Shor.nb where each algorithm is explained in detail. Finally, two examples of the construction and manipulation of cluster states, which are part of “one way computing” ideas, are included as an additional tool in the notebook Cluster.nb. A Mathematica palette containing most commands in QDENSITY is also included: QDENSpalette.nb.
Program summary
Title of program: QDENSITYCatalogue identifier: ADXH_v1_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/ADXH_v1_0Program available from: CPC Program Library, Queen's University of Belfast, N. IrelandOperating systems: Any which supports Mathematica; tested under Microsoft Windows XP, Macintosh OS X, and Linux FC4Programming language used: Mathematica 5.2No. of bytes in distributed program, including test data, etc.: 180 581No. of lines in distributed program, including test data, etc.: 19 382Distribution format: tar.gzMethod of solution: A Mathematica package is provided which contains commands to create and analyze quantum circuits. Several Mathematica notebooks containing relevant examples: Teleportation, Shor's Algorithm and Grover's search are explained in detail. A tutorial, Tutorial.nb is also enclosed. 相似文献97.
A bunch is a simple data structure, similar in many respects to a set. However, bunches differ from sets in that the data is not
packaged up or encapsulated, and in particular in that a bunch consisting of one element is the same as that element. Bunches
are attractive for handling nondeterminacy and underspecification, by which is meant that for any particular input to the
program or specification, the associated output is not fully determined. The acceptable outputs for any given input can be
described by a bunch. This approach nicely generalises traditional single-output programs and specifications. We present a
formal theory of bunches. It includes an axiomatisations of boolean and function types whose behaviour is well-known to be
complicated by the presence of nondeterminacy. The axiomatisation of the booleans preserves most of the laws of classical
predicate calculus. The axiomatisation of functions accommodates higher-order functions in all their generality, while avoiding
the dangers of inconsistency when functions and nondeterminacy intermix. Our theory is presented as a Hilbert-style system
of axioms and inference rules for a small specification language. We prove consistency.
Received: 23 December 1998 / 2 November 1999 相似文献
98.
A precise calculation of the amount of intraalveolar fluid is the basis of a quantitative analysis of intraalveolar compounds. Different approaches have been made to cover this important problem. Here, we report a comparative study with five markers: 99mTc-DTPA, 51Cr-EDTA, inulin, urea, and methylene blue in animal experiments as well as in human experiments. The marker substances were added to the lavage fluid, and the "dilution" of the markers, i.e., the alveolar fluid, was calculated. The results showed that in animals with healthy lungs the tracer methods are able to calculate amounts of intraalveolar fluid that are comparable to morphologic findings. In animals as well as in humans, methylene blue and inulin were shown to be useless in determining alveolar fluid volume compared with the tracer methods. In humans, the calculations with the urea method and with Tc-DTPA were in the same magnitude, but there was no individual correlation. We conclude that, at present, the methods to quantitate alveolar fluid volume lack precision and add nothing to a deeper understanding of alveolar biology. 相似文献
99.
Rain and icecrystal depolarization measurements were made on earthspace paths at four locations across Canada using the circularlypolarized 11.7 GHz beacon transmission from the cts satellite. Results show that when rain is the dominant depolarization mechanism, crosspolarization discrimination (xpd)is statistically related to copolar attenuation (cpa)according to xpd =U?20 log cpa with U showing improvement with increasing elevation angle. Icecrystal depolarization events, with accompanying differential phase shifts as large as 20°, were also observed. An analysis separating these events from the data demonstrates that at 11.7 GHz icecrystal depolarization degrades xpd statistics by less than 1 dB at the small percentages of time. 相似文献
100.
We introduce a new algorithm for computing Euclidean shortest paths in the plane in the presence of polygonal obstacles. In particular, for a given start points, we build a planar subdivision (ashortest path map) that supports efficient queries for shortest paths froms to any destination pointt. The worst-case time complexity of our algorithm isO(kn log2
n), wheren is the number of vertices describing the polygonal obstacles, andk is a parameter we call the illumination depth of the obstacle space. Our algorithm usesO(n) space, avoiding the possibly quadratic space complexity of methods that rely on visibility graphs. The quantityk is frequently significantly smaller thann, especially in some of the cases in which the visibility graph has quadratic size. In particular,k is bounded above by the number of different obstacles that touch any shortest path froms.Partially supported by NSF Grants IRI-8710858 and ECSE-8857642 and by a grant from Hughes Research Laboratories, Malibu, CA. 相似文献