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31.
For every piece of business software sold, at least one illegal copy exists. This article describes and classifies software-protection methods. 相似文献
32.
Pre-mRNA splicing is an essential step in gene expression and is catalyzed by two machineries in eukaryotes: the major (U2 type) and minor (U12 type) spliceosomes. While the majority of introns in humans are U2 type, less than 0.4% are U12 type, also known as minor introns (mi-INTs), and require a specialized spliceosome composed of U11, U12, U4atac, U5, and U6atac snRNPs. The high evolutionary conservation and apparent splicing inefficiency of U12 introns have set them apart from their major counterparts and led to speculations on the purpose for their existence. However, recent studies challenged the simple concept of mi-INTs splicing inefficiency due to low abundance of their spliceosome and confirmed their regulatory role in alternative splicing, significantly impacting the expression of their host genes. Additionally, a growing list of minor spliceosome-associated diseases with tissue-specific pathologies affirmed the importance of minor splicing as a key regulatory pathway, which when deregulated could lead to tissue-specific pathologies due to specific alterations in the expression of some minor-intron-containing genes. Consequently, uncovering how mi-INTs splicing is regulated in a tissue-specific manner would allow for better understanding of disease pathogenesis and pave the way for novel therapies, which we highlight in this review. 相似文献
33.
Ghada Ziadeh Sossy Shadarevian Amal Malek Joanna Khalil Tharwat Haddad John Haddad Imad Toufeili 《Journal of food science》2005,70(8):s548-s552
Pita bread loaves were prepared from flours fortified with calcium carbonate, calcium sulfate, and tricalcium dicitrate at 8 ascending levels to provide ranges of 800 to 2500, 700 to 1500, and 400 to 2000 mg of added Ca/100 g flour, respectively. The detection thresholds of calcium salts in pita bread were determined by the 3‐alter‐native forced choice (3‐AFC) test and construction of dose‐response curves. Detection thresholds determined by calculating geometric mean of individual best estimate thresholds, using criterion of 50%‐above‐chance and probit analysis of 3‐AFC data, were in the middle region of calcium concentrations. Analysis of dose‐response curves yielded values for thresholds outside the range of surveyed calcium concentrations. The detection threshold of CaSO4 (2724 mg/100 g) in pita bread was significantly higher (P < 0.01) than those of calcium carbonate (1984 mg/100 g) and tricalcium dicitrate (2132 mg/100 g). Calcium‐fortified pita bread was similar (P < 0.01) to its regular counterpart when formulated to contain 1254.6, 1772.5, or 1155 mg/100 g of CaCO3, CaSO4, or tricalcium dicitrate, respectively. At the indicated levels of fortification, calcium‐fortified pita bread is expected to provide between 61% and 126.5% of the recommended daily intake for calcium for Middle Eastern populations. 相似文献
34.
Ahmed H. Abd El‐Malek Fawaz S. Al‐Qahtani Salam A. Zummo Hussein Alnuweiri 《Wireless Communications and Mobile Computing》2016,16(14):2098-2115
In this paper, we examine the impact of antenna correlation on transmit antenna selection with receive maximal ratio combining (TAS/MRC) in multiple‐input multiple‐output multiuser underlay cognitive radio network (MIMO‐MCN) over a Nakagami‐m fading environment. The secondary network under consideration consists of a single source and M destinations equipped with multiple correlated antennas at each node. The primary network composed of L primary users, each of which is equipped with multiple correlated antennas. For the considered underlay spectrum sharing paradigm, the transmission power of the proposed secondary system is limited by the peak interference limit on the primary network and the maximum transmission power at the secondary network. In particular, we derive exact closed‐form expressions for the outage probability and average symbol error rate of the proposed secondary system. To gain further insights, simple asymptotic closed‐form expressions for the outage probability and symbol error rate are provided to obtain the achievable diversity order and coding gain of the system. In addition, the impact of antenna correlation on the secondary user ergodic capacity has been investigated by deriving closed‐form expressions for the secondary user capacity. The derived analytical formulas herein are supported by numerical and simulation results to clarify the main contributions. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
35.
In the real world, projects are subject to numerous uncertainties at different levels of planning. Fuzzy project scheduling is one of the approaches that deal with uncertainties in project scheduling problem. In this paper, we provide a new technique that keeps uncertainty at all steps of the modelling and solving procedure by considering a fuzzy modelling of the workload inspired from the fuzzy/possibilistic approach. Based on this modelling, two project scheduling techniques, Resource Constrained Scheduling and Resource Leveling, are considered and generalized to handle fuzzy parameters. We refer to these problems as the Fuzzy Resource Constrained Project Scheduling Problem (FRCPSP) and the Fuzzy Resource Leveling Problem (FRLP). A Greedy Algorithm and a Genetic Algorithm are provided to solve FRCPSP and FRLP respectively, and are applied to civil helicopter maintenance within the framework of a French industrial project called Helimaintenance. 相似文献
36.
In this paper, we have collected the requirements for Digital Rights Management from various sources, and presented them as
a set of 11 requirements, associated with five categories. We discuss each requirement, provide the motivation for each entry,
and illustrate how each one could be achieved. Four example commercial DRM systems are briefly explained, and the requirements
that they meet are presented in tabular format. None of the example systems meet all the requirements that we have listed.
The security threats that are faced by DRM systems are briefly discussed. All of the example systems are based on unicast
data distribution. The use of multicast data distribution can help the source of the data and the underlying network to reduce
their resource requirements when distributing high-quality content at minimum cost and delay. Up to now, there has been little
motivation to use standard Internet Protocol multicast because it does not support any protection mechanisms for the delivered
data. Given that significant progress has been made by other researchers in providing “secure” multicast data distribution,
we explore how the use of secure multicast as a distribution technology can bring significant improvement for some requirements,
while making the achievement of others more difficult. We review how the architecture of the distribution must change to permit
capturing the advantages of multicast distribution while retaining as much as possible the features of unicast systems. Some
open problems are identified. 相似文献
37.
M. Sahli C. Millot C. Roques-Carmes C. Khan Malek T. Barriere J.C. Gelin 《Journal of Materials Processing Technology》2009,209(18-19):5851-5861
This paper describes observations and metrological analyses made to compare the replication quality of polymeric replicas obtained by filling micro-cavities using both hot embossing and micro-injection moulding processes. The experiments are performed with polypropylene (PP) at a constant melt temperature and a constant mould temperature, whereas hot embossing tests are carried out with the same polymer at temperatures close to the softening one.The results concerning the micro-cavities filling provide information on the reliability about the possibilities of replication topographical surface geometries. The data obtained by scanning mechanical microscopy (SMM) are used to determine the comparative filling ratio values. 相似文献
38.
S. Malek 《Journal of Dynamical and Control Systems》2011,17(2):243-271
We study a q-analog of a singularly perturbed Cauchy problem with irregular singularity in the complex domain. We construct solutions
of this problem that are holomorphic on open half-q-spirals. Using a version of a q-analog of the Malgrange–Sibuya theorem obtained by J.-P. Ramis, J. Sauloy, and C. Zhang, we show the existence of a formal
power-series solution in the perturbation parameter which is the q-asymptotic expansion of these holomorphic solutions. 相似文献
39.
The X-ray micromachining activities at CAMD are described. Through the HI-MEMS Alliance Program, CAMD has developed an extensive
technical infrastructure and process experience. The “X-ray Print-Shop” supports prototyping and is prepared for cost effective
low-to-medium volume production of primary parts with high aspect ratio, including exposure of multiple level devices with
alignment, as well as tilted and rotated exposures. Important lessons learnt during the course of the program will be reported.
An up-grade of the facility to install a 7.5 Tesla superconducting wiggler in the ring is in progress. It will produce hard
X-rays for ultra-deep X-ray lithography.
Received: 25 August 1997/Accepted: 3 September 1997 相似文献
40.
The aerodynamic characteristics of wind turbines are closely related to the geometry of their blades. The innovation and the technological development of wind turbine blades can be centred on two tendencies. The first is to improve the shape of existing blades; the second is to design new shapes of blades. The aspiration in the two cases is to achieve an optimal circulation and hence enhancing some more ambitious aerodynamic characteristics. This paper presents an inverse design procedure, which can be adapted to both thin and thick wind turbine blade sections aiming to optimise the geometry for a prescribed distribution of bound vortices. A method for simulating the initial contour of the blade section is exposed, which simultaneously satisfy the aerodynamic and geometrical constraints under nominal conditions. A detailed definition of the function characterising the bound vortex distribution is presented. The inviscid velocity field and potential function distributions are obtained by the singularities method. In the design method implemented, these distributions and the circulation of bound vortices on the camber line of the blade profile, are used to rectify its camber in an iterative calculation leading to the final and optimal form of the blade section once convergence is attained. The scheme proposed has been used to design the entire blade of the wind turbine for a given span-wise distribution of bound circulation around the blade contour. 相似文献