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61.
Faranak Mavandadnejad Mohammad Hossein Yazdi Seyed Mehdi Hassanzadeh Mehdi Mahdavi Mohammad Ali Faramarzi Hamidreza PazokiToroudi Ahmad Reza Shahverdi 《IET nanobiotechnology / IET》2018,12(1):57
Conventional hepatitis B vaccine contains alum but is less effective to induce Th1 response. Selenium nanoparticles and Bacillus Calmette–Guerin were reported as immune modulators. In this study, SeNPs were extracted from Mycobacterium bovis and characterised. SeNPs were mixed with HBs‐Ag and administered to the mice to investigate he immune response pattern. With an addition of Se ions at a sub‐inhibitory concentration to the Sauton medium broth after 24 h, SeNPs were extracted from M. bovis and characterised by Fourier transform infrared spectroscopy, dynamic light scattering, atomic forcemicroscopy, energy dispersive X‐ray spectrum, transmission electron microscopy, and thermogravimetric analysis. Furthermore, female inbred BALB/c mice were injected subcutaneously on the first, 14th, 28th day with 100 and 200 µg doses of that SeNPs supplemented with HBs‐Ag vaccine. Later, the total antibody, isotypes of Immunoglobulin G1, Interlukin 4, and interferon‐γ were measured by enzye‐linked immunosorbent assay. The size of the SeNPs was <150 nm. Level of total antibody and immunoglobulin G2a increased significantly in the group that received 200 µg/ml nano selenium extracted from M. bovis. SeNPs in dose of 200 µg coated with organic materials of M. bovis could induce an influential immune response in relation to the conventional HBs‐Ag vaccine.Inspec keywords: selenium, nanoparticles, nanofabrication, microorganisms, Fourier transform spectra, infrared spectra, light scattering, atomic force microscopy, X‐ray chemical analysis, transmission electron microscopy, thermal analysis, nanomedicineOther keywords: biosynthesis, selenium nanoparticles, Mycobacterium bovis, enhnced immune response, HBs antigens, Bacillus Calmette‐Guerin, immune modulators, biogenic SeNPs, immune response pattern, Sauton medium broth, Fourier transform infrared spectroscopy, dynamic light scattering, atomic force microscopy, energy dispersive X‐ray spectrum, transmission electron microscopy, thermogravimetric analysis, female inbred BALB/c mice, antibody, IgG1 isotype, IgG2a isotype, IL4 isotype, interferon‐γ, enzyme‐linked immunosorbent assay, bacterium, time 24 h, time 14 day, time 28 day, Se 相似文献
62.
Mahwish Pervaiz Mohammad Shorfuzzaman Abdulmajeed Alsufyani Ahmad Jalal Suliman A. Alsuhibany Jeongmin Park 《计算机、材料和连续体(英文)》2023,74(1):841-853
Crowd management becomes a global concern due to increased population in urban areas. Better management of pedestrians leads to improved use of public places. Behavior of pedestrian’s is a major factor of crowd management in public places. There are multiple applications available in this area but the challenge is open due to complexity of crowd and depends on the environment. In this paper, we have proposed a new method for pedestrian’s behavior detection. Kalman filter has been used to detect pedestrian’s using movement based approach. Next, we have performed occlusion detection and removal using region shrinking method to isolate occluded humans. Human verification is performed on each human silhouette and wavelet analysis and particle gradient motion are extracted for each silhouettes. Gray Wolf Optimizer (GWO) has been utilized to optimize feature set and then behavior classification has been performed using the Extreme Gradient (XG) Boost classifier. Performance has been evaluated using pedestrian’s data from avenue and UBI-Fight datasets, where both have different environment. The mean achieved accuracies are 91.3% and 85.14% over the Avenue and UBI-Fight datasets, respectively. These results are more accurate as compared to other existing methods. 相似文献
63.
Md. Salah Uddin Afsar Mohammad Rashed Iqbal Faruque Sabirin Abdullah Mohammad Tariqul Islam 《计算机、材料和连续体(英文)》2023,76(1):455-469
This study proposed a new royal crown-shaped polarisation insensitive double negative triple band microwave range electromagnetic metamaterial absorber (MA). The primary purpose of this study is to utilise the exotic characteristics of this perfect metamaterial absorber (PMA) for microwave wireless communications. The fundamental unit cell of the proposed MA consists of two pentagonal-shaped resonators and two inverse C-shaped metallic components surrounded by a split ring resonator (SRR). The bottom thin copper deposit and upper metallic resonator surface are disjoined by an FR-4 dielectric substrate with 1.6 mm thickness. The CST MW studio, a high-frequency electromagnetic simulator has been deployed for numerical simulation of the unit cell in the frequency range of 4 to 14 GHz. In the TE mode, the offered MA structure demonstrated three different absorption peaks at 6.85 GHz (C-band), 8.87 GHz (X-band), and 12.03 GHz (Ku-band), with 96.82%, 99.24%, and 99.43% absorptivity, respectively. The electric field, magnetic field, and surface current distribution were analysed using Maxwell’s-Curl equations, whereas the angle sensitivity was investigated to comprehend the absorption mechanism of the proposed absorber. The numerical results were verified using the Ansys HFSS (high-frequency structure simulator) and ADS (advanced design system) for equivalent circuit models. Moreover, the proposed MA is polarisation and incident angle independent. Hence, the application of this MA can be extended to a great extent, including airborne radar applications, defence, and stealth-coating technology. 相似文献
64.
Asieh Khosravanian Mohammad Rahmanimanesh Parviz Keshavarzi Saeed Mozaffari 《International journal of imaging systems and technology》2023,33(1):323-339
Magnetic resonance imaging (MRI) brain tumor segmentation is a crucial task for clinical treatment. However, it is challenging owing to variations in type, size, and location of tumors. In addition, anatomical variation in individuals, intensity non-uniformity, and noises adversely affect brain tumor segmentation. To address these challenges, an automatic region-based brain tumor segmentation approach is presented in this paper which combines fuzzy shape prior term and deep learning. We define a new energy function in which an Adaptively Regularized Kernel-Based Fuzzy C-Means (ARKFCM) Clustering algorithm is utilized for inferring the shape of the tumor to be embedded into the level set method. In this way, some shortcomings of traditional level set methods such as contour leakage and shrinkage have been eliminated. Moreover, a fully automated method is achieved by using U-Net to obtain the initial contour, reducing sensitivity to initial contour selection. The proposed method is validated on the BraTS 2017 benchmark dataset for brain tumor segmentation. Average values of Dice, Jaccard, Sensitivity and specificity are 0.93 ± 0.03, 0.86 ± 0.06, 0.95 ± 0.04, and 0.99 ± 0.003, respectively. Experimental results indicate that the proposed method outperforms the other state-of-the-art methods in brain tumor segmentation. 相似文献
65.
We report a new technique for conducting immuno-diagnostics on a microfluidic platform. Rather than handling fluid reagents
against a stationary solid phase, the platform manipulates analyte-coated magnetic beads through stationary plugs of fluid
reagents to detect an antigenic analyte. These isolated but accessible plugs are pre-encapsulated in a microchannel by capillary
force. We call this platform microfluidic inverse phase enzyme-linked immunosorbent assay (μIPELISA). μIPELISA has distinctive
advantages in the family of microfluidic immunoassay. In particular, it avoids pumping and valving fluid reagents during assaying,
thus leading to a lab-on-a-chip format that is free of instrumentation for fluid actuation and control. We use μIPELISA to
detect digoxigenin-labeled DNA segments amplified from E. coli O157:H7 by polymerase chain reaction (PCR), and compare its detection capability with that of microplate ELISA. For 0.259 ng μl−1 of digoxigenin-labeled amplicon, μIPELISA is as responsive as the microplate ELISA. Also, we simultaneously conduct μIPELISA
in two parallel microchannels. 相似文献
66.
Nariman Mahdavi Mohammad Bagher Menhaj 《International Journal of Control, Automation and Systems》2011,9(1):104-111
In this paper, we consider a Hopfield like Chaotic Neural Networks which have both self-coupling and non-invertible activation
functions. We show that the interactions between neurons can be used as a means of chaos generation or suppression to neuron’s
outputs when more adaptability or stability is required. Furthermore, a new set of sufficient conditions based on coupling
weights is proposed so that the synchronization of all neuron’s outputs with each other is guaranteed, when all neuron’s have
identical activation functions. Finally, the effectiveness of the proposed approach is evaluated by performing simulations
on three illustrative examples. 相似文献
67.
Multi-level (ML) quantum logic can potentially reduce the number of inputs/outputs or quantum cells in a quantum circuit which
is a limitation in current quantum technology. In this paper we propose theorems about ML-quantum and reversible logic circuits.
New efficient implementations for some basic controlled ML-quantum logic gates, such as three-qudit controlled NOT, Cycle,
and Self Shift gates are proposed. We also propose lemmas about r-level quantum arrays and the number of required gates for an arbitrary n-qudit ML gate. An equivalent definition of quantum cost (QC) of binary quantum gates for ML-quantum gates is introduced and
QC of controlled quantum gates is calculated. 相似文献
68.
Karun Rawat Fadhel M. Ghannouchi Meenakshi Rawat Mohammad S. Hashmi 《国际射频与微波计算机辅助工程杂志》2011,21(3):325-335
This article proposes an analytical design methodology for dual‐band hybrid couplers and baluns structures for any arbitrary frequency ratio using a stub‐loaded transmission line. An analysis of changing the impedance behavior of the stub, is carried out for the two bands of operation, which along with a dispersive analysis, emphasizes certain conditions where the existing methodology is not applicable. In addition, an extra degree of freedom has been included to increase the solutions for a given frequency ratio, thus providing greater flexibility and feasibility of the proposed structure. The design methodology is experimentally validated with the design and fabrication of dual‐band branch‐line and rat‐race couplers for various commercial frequency bands. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE , 2011. 相似文献
69.
Sudip Misra Author Vitae Author Vitae Mohammad S. Obaidat Author Vitae Pushkar Gupta Author Vitae Author Vitae Prayag Narula Author Vitae 《Journal of Systems and Software》2010,83(11):2188-2199
Primitive routing protocols for ad-hoc networks are “power hungry” and can therefore consume considerable amount of the limited amount of battery power resident in the nodes. Thus, routing in ad-hoc networks is very much energy-constrained. Continuous drainage of energy degrades battery performance as well. If a battery is allowed to intermittently remain in an idle state, it recovers some of its lost charge due to the charge recovery effect, which, in turn, results in prolonged battery life.In this paper, we use the ideas of naturally occurring ants’ foraging behavior (Dorigo and Stuetzle, 2004) [1] and based on those ideas, we design an energy-aware routing protocol, which not only incorporates the effect of power consumption in routing a packet, but also exploits the multi-path transmission properties of ant swarms and, hence, increases the battery life of a node. The efficiency of the protocol with respect to some of the existing ones has been established through simulations. It has been observed that the energy consumed in the network, the energy per packet in the case of EAAR are 60% less compared to MMBCR and the packets lost is only around 12% of what we have in AODV, in mobility scenarios. 相似文献
70.
Mohammad Shorfuzzaman Peter Graham Rasit Eskicioglu 《The Journal of supercomputing》2010,51(3):374-392
Data grids support access to widely distributed storage for large numbers of users accessing potentially many large files.
Efficient access is hindered by the high latency of the Internet. To improve access time, replication at nearby sites may
be used. Replication also provides high availability, decreased bandwidth use, enhanced fault tolerance, and improved scalability.
Resource availability, network latency, and user requests in a grid environment may vary with time. Any replica placement
strategy must be able to adapt to such dynamic behavior. In this paper, we describe a new dynamic replica placement algorithm,
Popularity Based Replica Placement (PBRP), for hierarchical data grids which is guided by file “popularity”. Our goal is to
place replicas close to clients to reduce data access time while still using network and storage resources efficiently. The
effectiveness of PBRP depends on the selection of a threshold value related to file popularity. We also present Adaptive-PBRP
(APBRP) that determines this threshold dynamically based on data request arrival rates. We evaluate both algorithms using
simulation. Results for a range of data access patterns show that our algorithms can shorten job execution time significantly
and reduce bandwidth consumption compared to other dynamic replication methods. 相似文献