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2.
M. Valsan D. Sundararaman K. Bhanu Sankara Rao S. L. Mannan 《Metallurgical and Materials Transactions A》1995,26(5):1207-1219
A comparative evaluation of the low-cycle fatigue (LCF) behavior of type 316LN base metal, 316 weld metal, and 316LN/316 weld
joints was carried out at 773 and 873 K. Total strain-controlled LCF tests were conducted at a constant strain rate of 3 ×
10−3 s−1 with strain amplitudes in the range ±0.20 to ±1.0 pct. Weld pads with single V and double V configuration were prepared by
the shielded metal-arc welding (SMAW) process using 316 electrodes for weld-metal and weld-joint specimens. Optical microscopy,
scanning electron microscopy (SEM), and transmission electron microscopy (TEM) of the untested and tested samples were carried
out to elucidate the deformation and the fracture behavior. The cyclic stress response of the base metal shows a very rapid
hardening to a maximum stress followed by a saturated stress response. Weld metal undergoes a relatively short initial hardening
followed by a gradual softening regime. Weld joints exhibit an initial hardening and a subsequent softening regime at all
strain amplitudes, except at low strain amplitudes where a saturation regime is noticed. The initial hardening observed in
base metal has been attributed to interaction between dislocations and solute atoms/complexes and cyclic saturation to saturation
in the number density of slip bands. From TEM, the cyclic softening in weld metal was ascribed to the annihilation of dislocations
during LCF. Type 316LN base metal exhibits better fatigue resistance than weld metal at 773 K, whereas the reverse holds true
at 873 K. The weld joint shows the lowest life at both temperatures. The better fatigue resistance of weld metal is related
to the brittle transformed delta ferrite structure and the high density of dislocations at the interface, which inhibits the
growth rate of cracks by deflecting the crack path. The lower fatigue endurance of the weld joint was ascribed to the shortening
of the crack initiation phase caused by surface intergranular crack initiation and to the poor crack propagation resistance
of the coarse-grained region in the heat-affected zone. 相似文献
3.
Silicon - The promising capability of Triple Material Surrounding Gate Junctionless Tunnel FET (TMSG – JL – TFET) based 6 T SRAM structure is demonstrated by employing... 相似文献
4.
Flyash, a waste product generated in large quantities in thermal power plants, has been posing problems of disposal. The purpose of the present work was to make a meaningful utilization of flyash as filler in neat epoxy resin matrix and 2% Polybutyleneterepthalate (PBT)/epoxy blend matrix. For this purpose, the tensile, flexural, compression, impact, chemical resistance, and water absorption properties were studied. Composites were made with varying proportion of flyash in epoxy resin and 2% PBT/epoxy blend matrix. Tensile, flexural, and compression properties were measured on a computerized universal testing machine, according to ASTM procedures. Impact strength was determined using izod impact tester for un‐notched specimens. PBT (2%)/epoxy blend matrix composites showed improved mechanical properties over neat epoxy flyash composites. All the composites were found to have good chemical resistance toward acids, solvents, and alkalies. These composites showed better water resistance over neat epoxy flyash composites. POLYM. ENG. SCI. 46:946–953, 2006. © 2006 Society of Plastics Engineers 相似文献
5.
Recognizing a subject given a set of biometrics is a fundamental pattern recognition problem. This paper builds novel statistical models for multibiometric systems using geometric and multinomial distributions. These models are generic as they are only based on the similarity scores produced by a recognition system. They predict the bounds on the range of indices within which a test subject is likely to be present in a sorted set of similarity scores. These bounds are then used in the multibiometric recognition system to predict a smaller subset of subjects from the database as probable candidates for a given test subject. Experimental results show that the proposed models enhance the recognition rate beyond the underlying matching algorithms for multiple face views, fingerprints, palm prints, irises and their combinations. 相似文献
6.
The content and positional distribution of CLA in TAG fractions of lamb tissues was examined with either preformed CLA or
the linoleic acid precursor of CLA in the diet as experimental treatments. The CLA content of phospholipid (PL) from these
tissues was also examined. Thirteen lambs were randomized to the following dietary treatments: (i) control diet (no supplement);
(ii) CLA supplementation (0.33 g d−1 for 21 d prior to weaning) to milk-replacer of pre-ruminating lambs, or (iii) feeding linoleic acid-rich oil (6% safflower
oil on a dry matter basis) to weaned ruminating lambs. At slaughter, tissue samples were procured from diaphragm, rib muscle,
and subcutaneous (SC) adipose tissue. Safflower oil supplementation in the diet resulted in an increase in CLA content of
the TAG from diaphragm, rib muscle, and SC adipose tissue by about threefold (P<0.05) on a mol% basis. CLA was localized to the sn-1/3 positions of TAG. Animals that received pre-formed CLA, however, had increased proportions of CLA at the sn-2 position of TAG from SC adipose tissue, suggesting that there were tissue-specific dietary effects and possible age-related
effects on the mode of FA incorporation into TAG. Safflower oil supplementation in the diet had no effect on the CLA content
of PL from diaphragm, rib muscle, and SC adipose tissue, suggesting that CLA was preferentially incorporated into the TAG
of these tissues. 相似文献
7.
The performance of Saponin over different electrolyte-mediated electrokinetic (EK) process for removal of Cr(III) from tannery sludge was assessed. Saponin exhibited maximum Cr(III) removal efficiency, i.e. 67.6–80.75% as compared to other groups of processing fluids. The possible mechanistic approach for the highest removal efficiency of saponin over other electrolytes may be attributed to synchronized effect of micelle formation and subsequent complexation and sorption of chromium ions. The highest electroosmotic flow rate of saponin indicated low electroosmotic resistance during EK process, which validates the observed trend. Therefore, saponin can be considered as a promising electrolyte for EK treatment of tannery sludge.
Abbreviation: CA: Citric acid; LA: lactic acid; OA: oxalic acid; BOD: biochemical oxygen demand; COD: chemical oxygen demand; EK: electokinetic. 相似文献
8.
This study explores a novel subspace projection-based approach for analysis of stressed speech. Studies have shown that stress influences the speech production system and it results in a large acoustic variation between the neutral and the stressed speech. This degrades the discrimination capability of an automatic speech recognition system trained on neutral speech when tested on stressed speech. An effort is made to reduce the acoustic mismatch by explicitly normalizing the stress-specific attributes. The stress-specific divergences are normalized by exploiting the subspace filtering technique. To accomplish this, an orthogonal projection based linear relationship between the speech and the stress information has been explored to filter an effective speech subspace, which consists of speech information. Speech subspace is constructed using K-means clustering followed by singular value decomposition method using neutral speech data. The speech and the stress information are separated by projecting the stressed speech orthogonally onto an effective speech subspace. Experimental results indicate that, the bases of an effective subspace comprises the first few eigenvectors corresponding to the highest eigenvalues. To further improve the system performance, both the neutral and the stressed speech are projected onto the lower dimensional subspace. The projections derived using the neutral speech employs heteroscedastic linear discriminant analysis in maximum likelihood linear transformations-based semi-tied adaptation framework. Consistent improvements are noted for the proposed technique in all the discussed cases. 相似文献
9.
Prostate cancer accounts for one-third of noncutaneous cancers diagnosed in US men and is a leading cause of cancer-related
death. Advances in Fourier transform infrared spectroscopic imaging now provide very large data sets describing both the structural
and local chemical properties of cells within prostate tissue. Uniting spectroscopic imaging data and computer-aided diagnoses
(CADx), our long term goal is to provide a new approach to pathology by automating the recognition of cancer in complex tissue.
The first step toward the creation of such CADx tools requires mechanisms for automatically learning to classify tissue types—a
key step on the diagnosis process. Here we demonstrate that genetics-based machine learning (GBML) can be used to approach
such a problem. However, to efficiently analyze this problem there is a need to develop efficient and scalable GBML implementations
that are able to process very large data sets. In this paper, we propose and validate an efficient GBML technique——based on an incremental genetics-based rule learner. exploits massive parallelisms via the message passing interface (MPI) and efficient rule-matching using hardware-implemented
operations. Results demonstrate that is capable of performing prostate tissue classification efficiently, making a compelling case for using GBML implementations
as efficient and powerful tools for biomedical image processing. 相似文献
10.
M. Usharani B. Sakthivel S. Gayathri Priya T. Nagalakshmi J. Shirisha 《计算机系统科学与工程》2023,44(2):1647-1657
Approximate computing is a popular field for low power consumption that is used in several applications like image processing, video processing, multimedia and data mining. This Approximate computing is majorly performed with an arithmetic circuit particular with a multiplier. The multiplier is the most essential element used for approximate computing where the power consumption is majorly based on its performance. There are several researchers are worked on the approximate multiplier for power reduction for a few decades, but the design of low power approximate multiplier is not so easy. This seems a bigger challenge for digital industries to design an approximate multiplier with low power and minimum error rate with higher accuracy. To overcome these issues, the digital circuits are applied to the Deep Learning (DL) approaches for higher accuracy. In recent times, DL is the method that is used for higher learning and prediction accuracy in several fields. Therefore, the Long Short-Term Memory (LSTM) is a popular time series DL method is used in this work for approximate computing. To provide an optimal solution, the LSTM is combined with a meta-heuristics Jellyfish search optimisation technique to design an input aware deep learning-based approximate multiplier (DLAM). In this work, the jelly optimised LSTM model is used to enhance the error metrics performance of the Approximate multiplier. The optimal hyperparameters of the LSTM model are identified by jelly search optimisation. This fine-tuning is used to obtain an optimal solution to perform an LSTM with higher accuracy. The proposed pre-trained LSTM model is used to generate approximate design libraries for the different truncation levels as a function of area, delay, power and error metrics. The experimental results on an 8-bit multiplier with an image processing application shows that the proposed approximate computing multiplier achieved a superior area and power reduction with very good results on error rates. 相似文献