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51.
Ken Uchiyama 《AI & Society》1998,12(4):287-295
The industries of Japan have developed by learning from Western industries, especially the USA, and by implementing many of their concepts and technologies. However, Japanese industries have often implemented these concepts and technologies in a very different way from the USA. For example, while the USA uses information systems in retail industries as a tool by which data are collected and analysed to control the market, in Japan this same technology is considered rather as a learning device to interpret the market. While in the USA the market is seen as a natural phenomenon capable of being controlled, the Japanese see it as an ambiguous phenomenon that is ever changing and is not capable of being controlled. Rather it is important to feel the change in the market itself.This paper introduces human centredness to the information system, and argues against modern rationalism, i.e. human versus technology, taking the case of use of POS data from the POS system (point of sale: a system that collects data on both the customer and goods sold by scanning bar codes that are attached to the surface of the goods) by the eminent Japanese retailer, Ito-Yokado. It emphasises an interactive concept of interaction between human and technology of the postmodern paradigm. 相似文献
52.
Sayyed Mohamad Azimi Gavin Nixon Jeremy Ahern Wamadewa Balachandran 《Microfluidics and nanofluidics》2011,11(2):157-165
This article introduces a novel magnetic bead-based DNA extraction and purification device using active magnetic mixing approach.
Mixing and separation steps are performed using functionalised superparamagnetic beads suspended in cell lysis buffer in a
circular chamber that is sandwiched between two external magnetic coils. Non-uniform nature of magnetic field causes temporal
and spatial distribution of beads within the chamber. This process efficiently mixes the lysis buffer and whole blood in order
to extract DNA from target cells. Functionalized surface of the magnetic beads then attract the exposed DNA molecules. Finally,
DNA-attached magnetic beads are attracted to the bottom of the chamber by activating the bottom magnetic coil. DNA molecules
are extracted from magnetic beads by washing and re-suspension processes. In this study, a circular PMMA microchamber, 25 μL
in volume, 500 μm in depth and 8 mm in diameter was fabricated to purify DNA from spiked bacterial cell cultures into the
whole blood sample using Promega Magazorb DNA extraction kit. The lysis efficiency was evaluated using a panel of Gram-positive
(Bacillus subtilis) and Gram-negative (Escherichia coli) bacterial cells cultures into the blood sample to achieve approximately 100,000 copy levels inside the chip. Manufacturer’s
standard extraction protocol was modified to a more simplified process suitable for chip-based extraction. The lysis step
was performed using 5 min incubation at 56 °C followed by 5 min incubation at room temperature for binding process. Temperature
rise was generated and maintained by the same external magnetic coils used for active mixing. The yield/purity and recovery
levels of the extracted DNA were evaluated using quantitative UV spectrophotometer and real-time PCR assay, respectively.
Real-time PCR results indicated efficient chip-based bacterial DNA extraction using modified extraction protocol comparable
to the standard bench-top extraction process. 相似文献
53.
Kazuto Okazaki Tatsuya Ogiwara Dongshin Yang Kentaro Sakata Ken Saito Yoshifumi Sekine Fumio Uchikoba 《Artificial Life and Robotics》2011,16(2):229-233
This article presents the micro-electro-mechanical systems (MEMS) microrobot which demonstrates locomotion controlled by hardware
neural networks (HNN). The size of the microrobot fabricated by the MEMS technology is 4 × 4 × 3.5 mm. The frame of the robot
is made of silicon wafer, and it is equipped with a rotary-type actuator, a link mechanism, and six legs. The rotary-type
actuator generates rotational movement by applying an electrical current to artificial muscle wires. The locomotion of the
microrobot is obtained by the rotation of the rotary-type actuator. As in a living organism, the HNN realized robot control
without using any software programs, A/D converters, or additional driving circuits. A central pattern generator (CPG) model
was implemented as an HNN system to emulate the locomotion pattern. The MEMS microrobot emulated the locomotion method and
the neural networks of an insect with the rotary-type actuator, the link mechanism, and the HNN. The microrobot performed
forward and backward locomotion, and also changed direction by inputting an external trigger pulse. The locomotion speed was
0.325 mm/s and the step width was 1.3 mm. 相似文献
54.
A key to overcoming the limitations of classical artificial intelligence and to deal well with enormous amounts of information
might be brain-like computing in which distributed representations of information are processed by dynamical systems without
using symbols. We present a method for such computing. We constructed an inference system using a nonmonotone neural network,
which is a kind of recurrent neural network with continuous-time dynamics. This system deduces a conclusion according to state
transitions of the network in which knowledge is embedded as trajectory attractors. It has the powerful ability of analogical
reasoning without special treatment for exceptional knowledge. We also propose a method of linking different neurodynamical
systems and show that two mutually interacting systems can process complex spatiotemporal patterns. 相似文献
55.
As the technology in computer graphics advances, Animated-Virtual Actors (AVAs) in Virtual Reality (VR) applications become increasingly rich and complex. Cognitive Theory of Multimedia Learning (CTML) suggests that complex visual materials could hinder novice learners from attending to the lesson properly. On the other hand, previous studies have shown that visual complexity correlates with presence and may increase the perceived affective quality of the virtual world, towards an optimal experience or flow. Increasing these in VR applications may promote enjoyment and higher cognitive engagement for better learning outcomes. While visually complex materials could be motivating and pleasing to attend to, would they affect learning adversely? We developed a series of VR presentations to teach second-year psychology students about the navigational behaviour of Cataglyphis ants with flat, cartoon, or lifelike AVAs. To assess learning outcomes, we used Program Ratings, which measured perception of learning and perceived difficulty, and retention and transfer tests. The results from 200 students did not reveal any significant differences in presence, perceived affective quality, or learning outcomes as a function of the AVA’s visual complexity. While the results showed positive correlations between presence, perceived affective quality and perception of learning, none of these correlates with perceived difficulty, retention, or transfer scores. Nevertheless, our simulation produced significant improvements on retention and transfer scores in all conditions. We discuss possible explanations and future research directions. 相似文献
56.
Ken C. K. Lee Wang-Chien Lee Baihua Zheng Huajing Li Yuan Tian 《The VLDB Journal The International Journal on Very Large Data Bases》2010,19(3):333-362
Given a set of data points in a multidimensional space, a skyline query retrieves those data points that are not dominated by any other point in the same dataset. Observing that the properties of Z-order space filling curves (or Z-order curves)
perfectly match with the dominance relationships among data points in a geometrical data space, we, in this paper, develop
and present a novel and efficient processing framework to evaluate skyline queries and their variants, and to support skyline
result updates based on Z-order curves. This framework consists of ZBtree, i.e., an index structure to organize a source dataset and skyline candidates, and a suite of algorithms, namely, (1) ZSearch, which processes skyline queries, (2) ZInsert, ZDelete and ZUpdate, which incrementally maintain skyline results in presence of source dataset updates, (3) ZBand, which answers skyband queries, (4) ZRank, which returns top-ranked skyline points, (5) k-ZSearch, which evaluates k-dominant skyline queries, and (6) ZSubspace, which supports skyline queries on a subset of dimensions. While derived upon coherent ideas and concepts, our approaches
are shown to outperform the state-of-the-art algorithms that are specialized to address particular skyline problems, especially
when a large number of skyline points are resulted, via comprehensive experiments. 相似文献
57.
Gavin Paul Stephen Webb Dikai Liu Gamini Dissanayake 《Robotics and Autonomous Systems》2011,59(7-8):543-554
This paper presents a system for Autonomous eXploration to Build A Map (AXBAM) of an unknown, 3D complex steel bridge structure using a 6 degree-of-freedom anthropomorphic robot manipulator instrumented with a laser range scanner. The proposed algorithm considers the trade-off between the predicted environment information gain available from a sensing viewpoint and the manipulator joint angle changes required to position a sensor at that viewpoint, and then obtains collision-free paths through safe, previously explored regions. Information gathered from multiple viewpoints is fused to achieve a detailed 3D map. Experimental results show that the AXBAM system explores and builds quality maps of complex unknown regions in a consistent and timely manner. 相似文献
58.
59.
Ken Kaneiwa 《Knowledge》2011,24(5):629-641
Order-sorted logic is a useful tool for knowledge representation and reasoning because it enables representation of sorted terms and formulas along with partially ordered sorts (called sort-hierarchy). However, this logic cannot represent more complex sorted expressions when they are true in any possible world (as rigid) or some possible worlds (as modality) such as time, space, belief, or situation. In this study, we extend order-sorted logic by introducing existential rigidity and many modalities. In the extended logic, sorted modal formulas are interpreted over the Cartesian product of sets of possible worlds. We present a new labeled tableau calculus to check the (un)satisfiability and validity of sorted modal formulas. 相似文献
60.
We propose a system that allows the user to design a continuous flow animation starting from a still fluid image. The basic idea is to apply the fluid motion extracted from a video example to the target image. The system first decomposes the video example into three components, an average image, a flow field and residuals. The user then specifies equivalent information over the target image. The user manually paints the rough flow field, and the system automatically refines it using the estimated gradients of the target image. The user semi-automatically transfers the residuals onto the target image. The system then approximates the average image and synthesizes an animation on the target image by adding the transferred residuals and warping them according to the user-specified flow field. Finally, the system adjusts the appearance of the resulting animation by applying histogram matching. We designed animations of various pictures, such as rivers, waterfalls, fires, and smoke. 相似文献