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991.
The delay performance of compression algorithms is particularly important when time-critical data transmission is required. In this paper, we propose a wavelet-based electrocardiogram (ECG) compression algorithm with a low delay property for instantaneous, continuous ECG transmission suitable for telecardiology applications over a wireless network. The proposed algorithm reduces the frame size as much as possible to achieve a low delay, while maintaining reconstructed signal quality. To attain both low delay and high quality, it employs waveform partitioning, adaptive frame size adjustment, wavelet compression, flexible bit allocation, and header compression. The performances of the proposed algorithm in terms of reconstructed signal quality, processing delay, and error resilience were evaluated using the Massachusetts Institute of Technology University and Beth Israel Hospital (MIT-BIH) and Creighton University Ventricular Tachyarrhythmia (CU) databases and a code division multiple access-based simulation model with mobile channel noise.  相似文献   
992.
Hypernasality is associated with various diseases and interferes with speech intelligibility. A recently developed quantitative index called voice low tone to high tone ratio (VLHR) was used to estimate nasalization. The voice spectrum is divided into low-frequency power (LFP) and high-frequency power (HFP) by a specific cutoff frequency (600 Hz). VLHR is defined as the division of LFP into HFP and is expressed in decibels. Voice signals of the sustained vowel [a :] and its nasalization in eight subjects with hypernasality were collected for analysis of nasalance and VLHR. The correlation of VLHR with nasalance scores was significant (r = 0.76, p < 0.01), and so was the correlation between VLHR and perceptual hypernasality scores (r = 0.80, p < 0.01). Simultaneous recordings of nasal airflow temperature with a thermistor and voice signals in another 8 healthy subjects showed a significant correlation between temperature rate of nasal airflow and VLHR (r = 0.76, p < 0.01), as well. We conclude that VLHR may become a potential quantitative index of hypernasal speech and can be applied in either basic or clinical studies.  相似文献   
993.
In this paper, three types of partial H-plane filters, having advantages of compact, low cost, and mass-producible properties, are presented as compact waveguide filters, which are implemented by partial H-plane waveguide. Two types of partial H-plane filters have the same frequency responses as those of conventional E- and H-plane filters, respectively, while their cross sections are one-quarter. To further reduce the length, the last type of partial H-plane filters is designed by using quarter-wavelength resonators. The length of this filter is shorter by 29.2% than that of the conventional E-plane filter. In addition, it has a superior spurious frequency response  相似文献   
994.
Cascaded repeaters are indispensable circuit elements in conventional on-chip clock distribution networks due to heavy loss characteristics of on-chip global interconnections. However, cascaded repeaters cause significant jitter and skew problems in clock distribution networks when they are affected by power supply switching noise generated by digital logic blocks located on the same die. In this letter, we present a new three-dimensional (3-D) stacked-chip star-wiring interconnection scheme to make a clock distribution network free from both on-chip and package-level power supply noise coupling. The proposed clock distribution scheme provides an extremely low-jitter and low-skew clock signal by replacing the cascaded repeaters with lossless star-wiring interconnections on a 3-D stacked-chip package. We have demonstrated a 500-MHz input/output (I/O) clock delivery with 34-ps peak-to-peak jitter and a skew of 11ps, while a conventional I/O clock scheme exhibited a 146-ps peak-to-peak jitter and a 177-ps skew in the same power supply noise environment  相似文献   
995.
Personality is an essential feature for creating socially interactive robots. Studies on this dimension will facilitate enhanced human–robot interaction (HRI). Using AIBO, a social robotic pet developed by Sony, we examined the issue of personality in HRI. In this gender-balanced 2 (AIBO personality: introvert vs. extrovert) by 2 (participant personality: introvert vs. extrovert) between-subject experiment (N = 48), we found that participants could accurately recognize a robot's personality based on its verbal and nonverbal behaviors. In addition, various complementarity attraction effects were found in HRI. Participants enjoyed interacting with a robot more when the robot's personality was complementary to their own personalities than when the robot's personality was similar to their own personalities. The same complementarity attraction effect was found in participants' evaluation of the robot's intelligence and social attraction. Participants' feelings of social presence during the interaction were a significant mediator for the complementarity attraction effects observed. Practical and theoretical implications of the current study for the design of social robots and the study of HRI were discussed.  相似文献   
996.
A novel bidirectional complementary metal-oxide-semiconductor (CMOS) transceiver for chip-to-chip optical interconnects operating at 2.5 Gb/s is proposed, which shares the common block of a receiver and a transmitter on a single chip. The share of the common block of two circuits makes it possible to save 55% or 20% of power dissipation, depending on the operating mode. The chip in 0.18-/spl mu/m CMOS technology occupies an area of 0.82/spl times/0.82 mm/sup 2/, 70% of the total area of a typical unshared transceiver chip. The transmitting and receiving modes of operation show -3-dB bandwidths of 2.2 and 2.4 GHz and electrical isolations of -28 and -40 dB, respectively.  相似文献   
997.
A useful and rather new simulation technique for connectors up to 6.25 GHz is presented and discussed in this paper. The proposed model extracts electrical parameters of a connector using time-domain reflectometry (TDR) measurements. A new technique was developed to obtain accurate impedance profiles using TDR and a multisegment approach that is effectively a distributed coupled model. The parameter extraction and characterization of connectors are discussed. The performance of the proposed segmented transmission line model is verified by simulation of the model in SPICE and by experimental measurement. The results show that the proposed model can simulate the electrical characteristics, including crosstalk and impedance, of high-density and high-speed connectors with satisfactory accuracy. Based on the proposed modeling and CAD simulators, the design and analysis of complicated high-density and high-speed connectors can be executed accurately and effectively. Compared with other previous models, the proposed model can significantly improve the accuracy of simulation.  相似文献   
998.
In this paper, we jointly consider the resource allocation and base-station assignment problems for the downlink in CDMA networks that could carry heterogeneous data services. We first study a joint power and rate allocation problem that attempts to maximize the expected throughput of the system. This problem is inherently difficult because it is in fact a nonconvex optimization problem. To solve this problem, we develop a distributed algorithm based on dynamic pricing. This algorithm provides a power and rate allocation that is asymptotically optimal in the number of mobiles. We also study the effect of various factors on the development of efficient resource allocation strategies. Finally, using the outcome of the power and rate allocation algorithm, we develop a pricing-based base-station assignment algorithm that results in an overall joint resource allocation and base-station assignment. In this algorithm, a base-station is assigned to each mobile taking into account the congestion level of the base-station as well as the transmission environment of the mobile.  相似文献   
999.
We propose a novel optical distribution network for multistage optical access network with multiple remote nodes (RNs) using 4skip0 filters. The system can be implemented by use of 1/spl times/N arrayed waveguide grating in the central office, cascaded RNs, and a plurality of optical network units (ONUs). It also employs colorless ONUs based on incoherent light injected Fabry-Pe/spl acute/rot laser diodes for low operation and maintenance cost. Experiment shows error-free transmission with simultaneous bidirectional 1.25 Gb/s per channel up to 20 km.  相似文献   
1000.
The design of grounding system often relies on the performance simulations. The evaluation of the current distribution of grounding system for many frequencies by using the method of moments (MoM) may take a long time since the impedance matrix must be recomputed at each new frequency. A multiobject adaptive spatial sampling approach is presented to construct the fitted model of the electric field intensity generated by a horizontal electric dipole. The [Z] matrix spatial interpolation technology with MoM is described to reduce the computational time needed for the transient characteristics analysis of a horizontal grounding system. The accuracy and computational time of the [Z] matrix interpolation method are compared with those of the direct MoM. The numerical examples show that the [Z] matrix spatial interpolation method can reduce the computation requirement effectively.  相似文献   
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