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61.
We have built a database that provides term vector information for large numbers of pages (hundreds of millions). The basic operation of the database is to take URLs and return term vectors. Compared to computing vectors by downloading pages via HTTP, the Term Vector Database is several orders of magnitude faster, enabling a large class of applications that would be impractical without such a database. This paper describes the Term Vector Database in detail. It also reports on two applications built on top of the database. The first application is an optimization of connectivity-based topic distillation. The second application is a Web page classifier used to annotate results returned by a Web search engine. 相似文献
62.
63.
Sudip Misra P. Venkata Krishna Akhil Bhiwal Amardeep Singh Chawla Bernd E. Wolfinger Changhoon Lee 《The Journal of supercomputing》2012,62(1):4-23
Reliable routing of packets in a Mobile Ad Hoc Network (MANET) has always been a major concern. The open medium and the susceptibility of the nodes of being fault-prone make the design of protocols for these networks a challenging task. The faults in these networks, which occur either due to the failure of nodes or due to reorganization, can eventuate to packet loss. Such losses degrade the performance of the routing protocols running on them. In this paper, we propose a routing algorithm, named as learning automata based fault-tolerant routing algorithm (LAFTRA), which is capable of routing in the presence of faulty nodes in MANETs using multipath routing. We have used the theory of Learning Automata (LA) for optimizing the selection of paths, reducing the overhead in the network, and for learning about the faulty nodes present in the network. The proposed algorithm can be juxtaposed to any existing routing protocol in a MANET. The results of simulation of our protocol using network simulator 2 (ns-2) shows the increase in packet delivery ratio and decrease in overhead compared to the existing protocols. The proposed protocol gains an edge over FTAR, E2FT by nearly 2% and by more than 10% when compared with AODV in terms of packet delivery ratio with nearly 30% faulty nodes in the network. The overhead generated by our protocol is lesser by 1% as compared to FTAR and by nearly 17% as compared to E2FT when there are nearly 30% faulty nodes. 相似文献
64.
G. Shobha M. Krishna S.C. Sharma 《软件学报》2006,17(8):1824-1836
1 Introduction Reliability in personal authentication is key to the security in any transactional database. Many physiological characteristics of humans i.e., biometrics, are typically time invariant, easy to acquire, and unique for every individual. Biom… 相似文献
65.
N. D. V. N. S. Murali Krishna Ligy Philip 《Clean Technologies and Environmental Policy》2005,7(4):285-293
Nitrogen dioxide (NO2) removal efficiency of a biotrikling filter was evaluated under different operating conditions. Activated alumina (AA) was
used as the immobilization matrix for Thiobacillus denitrificans (T. denitrificans) in the biotrickling filter. Batch studies were conducted to find out the degradation kinetics of nitrate and nitrite for
a concentration range of 600–10,000 mg/L expressed as nitrogen. Nitrite exhibited maximum degradation rate followed by nitrate.
Electron acceptor in the form of NO2 gas showed least removal efficiency. Bio-kinetic parameters for T. denitrificans, by utilizing nitrate and nitrite as electron acceptors, were also evaluated. The μmax (Maximum specific growth rate) and YT (Yield coefficient) values for T. denitrificans in the presence of nitrate and nitrite were 1.03 h−1, 0.275 and 0.63 h−1, 0.1316 respectively. Column study was conducted to find the adsorption and desorption potential of activated alumina. The
adsorbed NO2 from AA could easily be desorbed using distilled water with an efficiency of 76±0.8%. Once fed batch studies were conducted
to evaluate the NO2 removal efficiency by a biotrickling filter. With an influent NO2 gas concentration of 2,735 ppm, the reactor could achieve a removal efficiency of 99% within 2 min from gas phase and within
96 h from the liquid phase, with an average biomass concentration of 200 mg/g of AA. The mechanism of NO2 gas removal in the biotrickling filter seems to be the dissolution of NO2 in water to form NO3−, conversion of NO3− to NO2
−, and finally to N2 gas. 相似文献
66.
Power and energy constraints are becoming increasingly prevalent in real-time embedded systems. Voltage-scaling is a promising technique to reduce energy and power consumption: clock speed tends to decrease linearly with supply voltage while power consumption goes down quadratically. We therefore have a tradeoff between the energy consumption of a task and the speed with which it can be completed. The timing constraints associated with real-time tasks can be used to resolve this tradeoff. In this paper, we present two algorithms for voltage-scaling. Assuming that a processor can operate in one of two modes: high voltage and low voltage, we show how to schedule the voltage settings so that deadlines are met while reducing the total energy consumed. We show that significant reductions can be made in energy consumption. 相似文献
67.
Ch. R. V. S. Nagesh Ch. Sridhar Rao N. B. Ballal P. Krishna Rao 《Metallurgical and Materials Transactions B》2004,35(1):65-74
The Kroll process of magnesium reduction of titanium tetrachloride is used the world over the production of titanium metal
in the form of sponge. Although the process has been in practice for the last five decades, there is no clear understanding
of the reaction mechanism and sponge formation. The present study involved reduction experiments in a 2000 kg titanium sponge-capacity
prototype reactor to develop a better understanding of TiCl4 reduction of magnesium with respect to the process parameters. Experiments were also conducted in two smaller experimental
reactors to study the temperature evolution during the process as a function of the TiCl4 feed rate. Based on the results of all these experiments, a model has been proposed for the mechanism of sponge formation
in the Kroll process. 相似文献
68.
Sandeep Peddi Rapur Ram Varalakshmi Devi Boreddy Sridhar Avssn Krishna Kishore Chennu Siva Kumar Vishnubotla 《Hemodialysis international. International Symposium on Home Hemodialysis》2014,18(1):192-194
We present an end‐stage renal disease patient on dialysis with fever. The primary source was right internal jugular vein catheter which had metastatic infections in the body probably via an arteriovenous communication in a cavity in left lung. Patient had right psoas muscle abscess and a left kidney abscess. An 18F‐fluorodeoxyglucose‐positron emission spectroscopy scan was done to find out left kidney abscess. A search of literature did not reveal many patients of psoas abscess secondary to infection of hemodialysis access. 相似文献
69.
Thrupathihalli Pandurangapp Krishna Murthy Balaraman Manohar 《International Journal of Food Science & Technology》2012,47(6):1229-1236
Curcuma amada (Mango ginger) was dried at four different power levels ranging 315–800 W to determine the effect of microwave power on moisture content, moisture ratio, drying rate, drying time and effective diffusivity. Among the fifteen thin layer drying models considered for evaluating the drying behaviour, the semi‐empirical Midilli et al., model described the drying kinetics very well with R2 > 0.999. Drying rate and effective diffusivity increased as the microwave power output increased. Activation energy was estimated by a modified Arrhenius type equation and found to be 21.6 kW kg?1. A feed‐forward artificial neural network using back‐propagation algorithm was also employed to predict the moisture content during MW drying and found adequate to predict the drying kinetics with R2 of 0.985. 相似文献
70.
Rajesh Krishna Ann Horowitz Patrick Larson James Bolognese Eugene E. Marcantonio 《Drug development and industrial pharmacy》2017,43(7):1173-1177
Objectives: A new improved mometasone furoate (Elocon?) cream with an emulsification system that produces a stable emulsion has been developed. In order to register the product in various markets, it was essential to ensure the cream was topically well tolerated and that it was bioequivalent to the reference product.Methods: Phase I clinical studies were performed to assess the local safety and tolerability upon multiple dosing of this new cream as well as to assess the single-dose bioequivalence relative to the marketed product. Bioequivalence was assessed using a vasoconstrictive assay (VCA) after a dose-duration pilot study was completed with the marketed Elocon cream.Key findings: The new mometasone cream and its vehicle were nonirritating in healthy subjects during 21-day patch application (MCII <0.025). The positive control was moderately irritating in the same study. The pivotal VCA study enrolled 162 subjects with 105 detectors included in the analysis of bioequivalence. In the 105 detectors, the ratio (×100%) of AUEC values at ED50 for test vs. standard (90% CI) was 112.91% (105.55, 120.87), within the bioequivalence criteria of (80, 125).Conclusions: These studies supported the registration of reformulated mometasone cream in various markets. 相似文献