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991.
In this study, we investigate the relationship between emotions and the physiological responses, with emotion recognition, using the proposed fuzzy information granulation–based neural network (FIGNN) for boredom, pain, and surprise emotions. For an analysis of the physiological responses, three emotions are induced through emotional stimuli, and the physiological signals are obtained from the evoked emotions. To recognize the emotions, we design an FIGNN recognizer and deal with the feature selection through an analysis of the physiological signals. The proposed method is accomplished in premise, consequence, and aggregation design phases. The premise phase takes information granulation using fuzzy c‐means clustering, the consequence phase adopts a polynomial function, and the aggregation phase resorts to a general fuzzy inference. Experiments show that a suitable methodology and a substantial reduction of the feature space can be accomplished, and that the proposed FIGNN has a high recognition accuracy for the three emotions using physiological signals.  相似文献   
992.
Recently, Hou and others introduced a (2, n) block‐based progressive visual cryptographic scheme (BPVCS) in which image blocks can be gradually recovered step by step. In Hou and others’ (2, n)‐BPVCS, a secret image is subdivided into n non‐overlapping image blocks. When participants stack their shadow images, all the image blocks associated with these t participants will be recovered. However, Hou and others’ scheme is only a simple 2‐out‐of‐n case. In this paper, we discuss a general (k, n)‐BPVCS for any k and n. Our main contribution is to give two constructions (Construction 1 and Construction 2) of this general (k, n)‐BPVCS. Also, we theoretically prove that both constructions satisfy a threshold property and progressive recovery of the proposed (k, n)‐BPVCS. For , Construction 1 is reduced to Hou and others’ (2, n)‐BPVCS.]  相似文献   
993.
In this paper, we propose a classification‐based approach for hybridizing statistical machine translation and rule‐based machine translation. Both the training dataset used in the learning of our proposed classifier and our feature extraction method affect the hybridization quality. To create one such training dataset, a previous approach used auto‐evaluation metrics to determine from a set of component machine translation (MT) systems which gave the more accurate translation (by a comparative method). Once this had been determined, the most accurate translation was then labelled in such a way so as to indicate the MT system from which it came. In this previous approach, when the metric evaluation scores were low, there existed a high level of uncertainty as to which of the component MT systems was actually producing the better translation. To relax such uncertainty or error in classification, we propose an alternative approach to such labeling; that is, a cut‐off method. In our experiments, using the aforementioned cut‐off method in our proposed classifier, we managed to achieve a translation accuracy of 81.5% — a 5.0% improvement over existing methods.  相似文献   
994.
This work proposes a highly efficient sensorless motor driver chip for various permanent‐magnet synchronous motors (PMSMs) in a wide power range. The motor driver chip is composed of two important parts. The digital part is a sensorless controller consisting mainly of an angle estimation block and a speed control block. The analog part consists of a gate driver,which is able to sense the phase current of a motor. The sensorless algorithms adapted in this paper include a sliding mode observer (SMO) method that has high robust characteristics regarding parameter variations of PMSMs. Fabricated SMO chips detect back electromotive force signals. Furthermore, motor current–sensing blocks are included with a 10‐bit successive approximation analog‐to‐digital converter and various gain current amplifiers for proper sensorless operations. Through a fabricated SMO chip, we were able to demonstrate rated powers of 32 W, 200 W, and 1,500 W.  相似文献   
995.
In this paper, a 0.35 V, 82 pJ/conversion ring oscillator based ultra-low power CMOS all digital temperature sensor is presented for on-die thermal management. We utilize subthreshold circuit operation to reduce power and adopt an all-digital architecture, consisting of only standard digital gates. Additionally, a linearization technique is proposed to correct the nonlinear characteristics of subthreshold MOSFETs. A bulk-driven 1-bit gated digitally controlled oscillator is designed for the temperature sensing node. Also, a 1-bit time-to-digital converter is employed in order to double the fine effective resolution of the sensor. The proposed digital temperature sensor has been designed in a 90-nm regular V T CMOS process. After a two-point calibration, the sensor has a maximum error of ?0.68 to +0.61 °C over the operating temperature range from 0 to 100 °C, while the effective resolution reaches 0.069 °C/LSB. Under a supply voltage of 0.35 V, the power dissipation is only 820 nW with the conversion rate of 10K samples/s at room temperature. Also, the sensor occupies a small area of 0.003 mm2.  相似文献   
996.
A Distributed Medium Access Control (D-MAC) protocol based on UWB for high-rate Wireless Personal Area Networks is specified by the WiMedia Alliance. D-MAC protocol is suitable for ubiquitous connection in home networks, military/medical applications due to its inexpensive cost, low power consumption, high data rate, and distributed approach. In contrast to IEEE 802.15.3, D-MAC makes all devices have the same functionality. And its networks are self-organized and provide devices with functions such as access to the medium, channel allocation to devices, data transmission, quality of service and synchronization in a distributed manner. D-MAC fundamentally removes the problems of the centralized MAC approach revealed at IEEE 802.15.3 MAC by adopting a distributed architecture. However, the current D-MAC can’t prevent QoS degradations, occurred by mobile nodes with low data rate due to bad channel status, which cause critical problems in QoS provisioning to isochronous streams and mobile applications. Therefore, we propose a distributed cooperative MAC protocol for multi-hop WiMedia networks using virtual MIMO links. Based on instantaneous Channel State Information among WiMedia devices, our proposed protocol can intelligently select the transmission path with higher data rate to provide advanced QoS with minimum delay for real-time multimedia streaming services.  相似文献   
997.
Cluster-based intrusion detection systems, where cluster heads (CHs) detect misbehavior of their member nodes, have been proposed in mobile ad-hoc networks (MANETs) in order to protect the network and save the energy. However, long-term survival of all nodes is more important so as not to partition the network. The extension of the network lifetime in the cluster-based IDS depends on which nodes are selected as CHs, which consume much more energy than cluster members due to monitoring them and detecting intrusions. In this paper, we propose a Distributed Energy Efficient Cluster Formation (DEECF) scheme, which exploits the expected residual energy of mobile nodes to select CHs and starts the cluster formation from leaf nodes to reduce the number of clusters. The scheme consists of the cluster construction algorithm and the cluster maintenance algorithm, both of which can be performed at each node in a distributed way without any global knowledge. We prove the correctness of the algorithms, and show that the DEECF scheme is more energy efficient than other clustering schemes by extensive simulation.  相似文献   
998.
Sensor‐based chemical analyses commonly enlist either the molecular recognition capabilities of biology (e.g., enzyme biosensors) or advanced information processing algorithms (e.g., the electronic nose). Here, a hybrid approach is proposed in which an enzyme is used to “filter” chemical information and write this information to a film which then serves as a permanent storage medium that can be ‘read’ repeatedly, interactively, and by multiple sensor modalities. This approach is demonstrated by analyzing common dietary phenols that are reported to offer health benefits. Specifically, the enzyme tyrosinase is used to convert these phenols into reactive quinones that graft (i.e., write) to a chitosan film. Grafting can be detected by optical, mechanical, and electrochemical sensors. Importantly, grafting confers redox activity to the films and this redox activity can be probed interactively by advanced electrochemical methods that allow the intrinsic redox reactivities to be compared, redox interactions to be identified, and biologically relevant redox activities to be examined. The transfer of chemical and biological information to a film is envisioned to provide broader access to the extensive capabilities offered by sensor technologies and signal processing methodologies.  相似文献   
999.
Small molecule pentacene layer has been a representative among many organic thin‐film transistor (OTFT) channels with decent p‐type mobilities, but it is certainly light‐sensitive due to its relatively small highest occupied molecular orbital‐lowest unoccupied molecular orbital (HOMO‐LUMO) gap (1.85 eV). Although a few other small molecule‐based layers have been reported later, their photo‐stabilities or related device applications have hardly been addressed. Here, a new photostable organic layer is reported, heptazole (C26H16N2), which has almost the same HOMO level as that of pentacene but with a higher HOMO‐LUMO gap (≈2.95 eV). This heptazole OTFT displays a decent mobility comparable to that of conventional amorphous Si TFTs, showing good photostability unlike pentacene OTFTs. An image pixel driving the photostable heptazole OTFT connected to a pentacene/Al Schottky photodiode is demonstrated. This heptazole OTFT also conveniently forms a logic inverter coupled with a pentacene OTFT, sharing Au for source/drain.  相似文献   
1000.
Indium‐doped tin oxide free electrochromic devices are prepared by coating electrochromic polymers onto polyethylene terephthalate substrates encompassing two different silver grids as electrodes. One design comprises a flexoprinted highly conductive silver grid electrode, yielding electrochromic devices with a response time of 2 s for an optical contrast of 27%. The other design utilizes an embedded silver grid electrode whereupon response times of 0.5 s for a 30% optical contrast are realized when oxidizing the device. A commercially available conductive poly(3,4‐ethylenedioxythiophene):poly(4‐styrenesulfonate acid) formulation (PEDOT:PSS) is coated onto the silver grids as a charge balancing polymer, and is in this setting found to be superior to a polypyrrole previously employed in electrochromic devices. In addition, the PEDOT:PSS layer increases the conductivity in the hexagonal grid structure.  相似文献   
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