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141.
In this paper, hum of a person (instead of normal speech) is used to design a voice biometric system for person recognition. In addition, a recently proposed static feature set, viz., Variable length Teager energy based Mel Frequency Cepstral Coefficients (VTMFCC), is found to capture source-like information of a hum signal. Effectiveness of VTMFCC over linear prediction (LP) residual to capture the complementary information than MFCC is demonstrated in a hum signal. Person recognition performance is found to be better when a score-level fusion is used by combining evidences from static and dynamic features for MFCC (system) and VTMFCC (source-like) features than MFCC alone. Experiments are validated on two types of dynamic features, viz., delta cepstrum and shifted delta cepstrum. In addition, for score-level fusion using static and dynamic features % identification rate and % Equal Error Rate are observed to outperform by 7.9?% and 0.27?%, respectively than MFCC alone. Furthermore, we have observed that person recognition system gives better performance for larger frame duration 69.6?ms as opposed to traditional 10–30?ms frame duration.  相似文献   
142.

The heat losses are mainly affects on the performance of cavity receiver of solar concentrator. In this paper, the experimental and numerical study is carried out for different heat losses from spherical cavity receiver of 0.385 m cavity diameter and 0.154 m opening diameter. The total and convection losses are studied experimentally to no wind and wind conditions for the temperature range of 150 °C to 300 °C at 0°, 30°, 45°, 60° and 90° inclination angle of cavity receiver. The experimental set up mainly consists of copper tube material cavity receiver wrapped with nichrome heating coil to heat the cavity and insulated with glasswool insulation. The numerical analysis was carried out with Fluent Computational fluid dynamics (CFD) software, to study connective heat losses for no wind condition only. The numerical results are compared with experimental results and found good agreement with maximum deviation of 12 %. The effect of inclination angle of cavity receiver on total losses & convection losses shows that as the inclination angle increases from 0o to 90o, both losses decreased due to decreased in convective zone into the cavity receiver. The effect of operating temperature of cavity shows that as the temperature of cavity receiver increases, the total and convective losses goes on increasing. The effect of external wind at 2 m/s and 4 m/s in two directions (side-on wind and head-on wind) is also studied experimentally for total and convective heat losses. The result shows that the heat losses are higher for head-on wind condition compared to side-on wind and no wind condition at all inclination angle of cavity receiver. The present results are also compared to the convective losses obtained from the correlations of Stine & Mcdonald and M. Prakash. The convective loss from these correlations shows nearest prediction to both experimental and numerical results.

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143.
Object-oriented applications are increasingly being deployed in distributed computing environments. Technologies, such as Java RMI, and architectures, such as CORBA, DCOM, and Enterprise Java Beans, are facilitating and enhancing this trend. The performance and eventual success of these applications is dependent on distribution decisions made by the application designer. This decision is a complex one, involving a large number of alternatives and multiple conflicting criteria. Rigorous approaches for effective distribution of object-oriented applications are still lacking. This paper describes the implementation of a practical and effective approach for distributing object-oriented applications. A prototype decision support system—object distribution environment (ODE)—that implements the approach in the form of a user-friendly tool for the design of distributed object-oriented applications is described. ODE has been successfully used in the distribution of a real world distributed object-oriented system.  相似文献   
144.
Mine Water and the Environment - As expected, a zeolite formed from lignite fly ash proved to be far more effective in treating the water from the Neyvelli lignite mines than the fly ash itself....  相似文献   
145.
While computing the regularized mean in medical image analysis, compensation for anatomical variation between different subjects is achieved by registering data with a standard template. In practice, template registration is never perfect and registration error (called jitter) can influence any statistic that is calculated using the template. This paper considers the design of regularizing filters which makes the effect of jitter harmless on the computed mean. The design is based on a new notion called jitter-resistant filtering. A regularizing kernel is jitter resistant if the effect of jitter on the regularized data is similar to a slight change in the scale of the kernel in the absence of jitter. Based on this notion, it is shown that the family of Gaussian filters is a jitter-resistant family of regularizing filters. Simulations in support of the theory are also presented.  相似文献   
146.
An experimental and computational study of NO formation in low-strain-rate partially premixed methane counterflow flames is reported. For progressive fuel-side partial premixing the peak NO concentration increased and the NO distribution along the stagnation streamline broadened. New temperature-dependent emissivity data for a SiO2-coated Pt thermocouple was used to estimate the radiation correction for the thermocouple, thus improving the accuracy of the reported flame temperature. Flame structure computations with GRIMech 3.00 showed good agreement between measured and computed concentration distributions of NO and OH radical. With progressive partial premixing the contribution of the thermal NO pathway to NO formation increases. The emission index of NO (EINO) first increased and then decreased, reaching its peak value for the level of partial premixing that corresponds to location of the nonpremixed reaction zone at the stagnation plane. The observation of a maximum in EINO at a level of partial premixing corresponding to the nonpremixed reaction zone at the stagnation plane seems to be a consistent feature of low (<20 s−1)-strain-rate counterflow flames.  相似文献   
147.
A new photoacid generator (PAG) bound polymer containing triphenylsulfonium salt methacrylate (TPSMA) was synthesized and characterized. The PAG bound polymer was employed to improve electron beam lithographic performance, including sensitivity and resolution. The PAG bound polymer resist exhibited a higher sensitivity (120 μC/cm2) than the PAG blend polymer resist (300 μC/cm2). Eliminating the post exposure baking process during development improved the resolution due to decreased acid diffusion. A high-resolution pattern fabricated by electron beam lithography had a line width of 15 nm and a high aspect ratio. The newly developed patterns functioned well as masks for transferring patterns on Si substrates by reactive ion etching.  相似文献   
148.
An efficient iron(III) chloride catalyzed synthesis of highly substituted indolyltetrahydroquinoline derivatives from easily available starting materials, including indolylnitroalkenes, substituted anilines and various aldehydes is reported. The reaction utilized strong electron deficient dienophiles like indolylnitroalkene via a Povarov approach. The methodology shows good functional group tolerance and can be used to prepare fused indolo‐benzonaphthyridine derivatives.

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149.
In this paper, we analyze the flicker and thermal noise model for underlap p-channel DG FinFET in weak inversion region. During the analysis of current and charge model, minimum channel potential i.e. virtual source is considered. Initially, the drain current for both long and short channel of DG FinFET are evaluated and found to be well interpreted with experimental results. Further, the flicker and thermal noise spectral density are derived. The flicker noise power spectral density is compared with published experimental results, which shows a good agreement between proposed model and experimental result. During calculation we have considered variation of scattering parameter and furthermore, the degradation of effective mobility is taken into account for ultrathin body. The variation of structural parameters such as gate length (Lg), body thickness (tSi) and underlap length (Lun) are also considered. The degradation of gate noise voltage with frequency, underlap length and gate length signify that p-channel DG FinFET device can be a promising candidate for analog and RF applications.  相似文献   
150.
A simplistic approach for synthesis of zinc sulphide (ZnS) nanorods is reported. The synthesis of ZnS nanoparticles involved mixing of zinc acetate, sodium sulphide and acrylic acid in appropriate ratio at proper conditions, which formed the core. These nanoparticles were trapped in PAA by in-situ polymerization of acrylic acid and carefully casted into the film which resulted into entrapped nanorods in the polymer matrix. The nanoparticles as well as nanorods entrapped in PAA were characterized using high resolution scanning electron microscopy (SEM) for morphological investigations; energy dispersive X-ray analysis (EDAX) for composition and its crystalinity was checked using X-ray diffraction (XRD). The length of nanorods was in the range of 2–4 μm and thickness between 50–200 nm.  相似文献   
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