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161.
An American Sign Language (ASL) recognition system is being developed using artificial neural networks (ANNs) to translate ASL words into English. The system uses a sensory glove called the Cyberglove™ and a Flock of Birds® 3-D motion tracker to extract the gesture features. The data regarding finger joint angles obtained from strain gauges in the sensory glove define the hand shape, while the data from the tracker describe the trajectory of hand movements. The data from these devices are processed by a velocity network with noise reduction and feature extraction and by a word recognition network. Some global and local features are extracted for each ASL word. A neural network is used as a classifier of this feature vector. Our goal is to continuously recognize ASL signs using these devices in real time. We trained and tested the ANN model for 50 ASL words with a different number of samples for every word. The test results show that our feature vector extraction method and neural networks can be used successfully for isolated word recognition. This system is flexible and open for future extension.  相似文献   
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163.
Recently we have described a splice variant of the L-type Ca2+ channel (alpha1C,86) in which 80 amino acids (1572-1651) of the conventional alpha1C,77 were substituted by another 81 amino acids due to alternative splicing of exons 40-42. Ba2+ current (IBa) through alpha1C,86 exhibited faster inactivation kinetics, was strongly voltage-dependent, and had no Ca2+-dependent inactivation. An oligonucleotide-directed segment substitution and expression of the mutated channels in Xenopus oocytes were used to study the molecular determinants for gating of the channel within the 80-amino acid domain. Replacement of segments 1572-1598 or 1595-1652 of the "slow" alpha1C,77 channel with the respective segments of the "fast" alpha1C,86 gave rise to rapidly inactivating alpha1C,86-like channel isoforms. We found that replacement of either motifs 1572IKTEG1576 or 1600LLDQV1604 of alpha1C,77 with the respective sequences of alpha1C,86 caused strong but partial acceleration of IBa inactivation. Replacement of both sequences produced an alpha1C, 86-like fast channel which had no Ca2+-dependent inactivation. These results support the hypothesis that motifs 1572-1576 and 1600-1604 of alpha1C,77 contribute cooperatively to inactivation kinetics of alpha1C and are critical for Ca2+-dependent inactivation of the channel.  相似文献   
164.
BACKGROUND: Many experts have suggested that blunt splenic trauma in patients older than 55 years should not be managed by observation because of supposed increased fragility of the spleen and decreased physiologic reserve in elderly patients. We sought to determine the outcome of nonoperative management of blunt splenic trauma in patients older than 55 years. METHODS: For the years 1994 through 1996, data for patients with splenic injury older than 55 years from seven trauma centers in a single state were reviewed. RESULTS: Blunt splenic trauma occurred in 41 patients older than 55 years. Eight patients were excluded from further analysis because of death from massive associated injuries within 24 hours of admission. The remaining 33 patients (mean age, 72+/-10 years) were divided into two groups: immediate exploration (10 patients) and observation (23 patients). Observation of blunt splenic injury failed in 4 of 23 patients (17%). No patient deaths were related to the method of management of the splenic injury. CONCLUSIONS: Observation of the elderly patient with blunt splenic trauma has an acceptable failure rate of 17%.  相似文献   
165.
The tear pharmacokinetic profiles of 0.3% ciprofloxacin, 0.3% ofloxacin, and 0.3% norfloxacin ophthalmic solutions after a single drop topically administrations in the eyes of 30 healthy volunteers were evaluated. Tear samples collected at 30, 120, 180, and 240 minutes, were analyzed for drug concentrations by high performance liquid chromatography (HPLC) with fluorometric detection. Topically applied ciprofloxacin, ofloxacin, and norfloxacin achieved the mean tear concentrations (mean +/- SD) of 11.28 +/- 6.98, 6.52 +/- 4.06, and 13.28 +/- 8.78 micrograms/g at 30 min, and then fell to 3.52 +/- 1.30, 4.82 +/- 1.80, and 5.79 +/- 4.80 micrograms/g at 240 min, respectively. Topical norfloxacin achieved mean tear level significantly higher than ofloxacin at 30 min (p = 0.031). There were no statistically significant differences in the mean tear levels of ciprofloxacin versus ofloxacin (at 30, 120, 180, and 240 min), ciprofloxacin versus norfloxacin (at 30, 120, 180, and 240 min) and ofloxacin versus norfloxacin (at 120, 180, and 240 min). However, the mean tear levels, 240 min after dosing ciprofloxacin and norfloxacin, fell to the statistically significant concentrations (p = 0.02 and p = 0.01, respectively). But, it is concluded that concentrations of ciprofloxacin, ofloxacin, and norfloxacin in tears were still significantly greater than the minimum inhibitory concentrations for the most sensitive organisms, 240 min after a single drop application.  相似文献   
166.
Na+-Ca2+ exchanger is one of the major sarcolemmal Ca2+ transporters of cardiac myocytes. In frog ventricular myocytes the exchanger is regulated by isoproterenol via a beta-adrenoreceptor/adenylate-cyclase/cAMPdependent signaling pathway providing a molecular mechanism for the relaxant effect of the hormone. Here, we report on the presence of a novel exon of 27-base pair insertion, which generates a nucleotide binding motif (P-loop) in the frog cardiac Na+-Ca2+ exchanger. To examine the functional role of this motif, we constructed a full-length frog heart Na+-Ca2+ exchanger cDNA (fNCX1a) containing this exon. The functional expression of fNCX1a in oocytes showed characteristic voltage dependence, divalent (Ni2+, Cd2+) inhibition, and sensitivity to cAMP in a manner similar to that of native exchanger in frog myocytes. In oocytes expressing the dog heart NCX1 or the frog mutant (DeltafNCX1a) lacking the 9-amino acid exon, cAMP failed to regulate Na+-dependent Ca2+ uptake. We suggest that this motif is responsible for the observed cAMP-dependent functional differences between the frog and the mammalian hearts.  相似文献   
167.
DNA typing of HLA-DRB1 genes was conducted for 192 samples from the Gidra who speak one of the non-Austronesian languages and inhabit the southern lowlands of New Guinea. Comparison of the allele frequencies with those of eight other Oceanian populations reveals that the Gidra are genetically closest to the non-Austronesian-speaking Goroka and, next, to the Aboriginal Australian groups, but are remote from the Austronesian-speaking groups in mainland New Guinea and the rest of Melanesia. This finding clearly supports the hypothesis that non-Austronesians and Aboriginal Australians are descendants of the first-stage migrants to Oceania.  相似文献   
168.
In this study, we report the synthesis of SrCo1?xRuxO3?δ nominal compositions, where x = 0.0‐1.0, using solid‐state reaction technique. XRD analysis confirms the structure of x = 0 sample as hexagonal Sr6Co5O15. As the Co ions are substituted by Ru, a two‐phase structure (hexagonal R32 and orthorhombic Pbnm) emerges up to x ≤ 0.5. As the Ru content is increased further, the hexagonal R32 phase disappears completely and an orthorhombic Pbnm phase becomes the main phase. SEM images show that grain size of the samples decreases with increasing Ru content. Temperature‐dependent electrical conductivity studies indicate upon Ru substitution in the nominal SrCo1?xRuxO3?δ compounds, resistivity decreases due to appearance of metallic SrRuO3 phase. The cyclic voltammogram (CV) of the samples show capacitive properties upon Ru substitution. The cycle measurements of the capacitors yield promising results for potential supercapacitor applications.  相似文献   
169.
In the present study the treatment efficiency of different AOPs (O3/OH- H2O2/UV-C and TiO2/UV-A) were compared for the oxidation of simulated reactive dyebath effluent containing a mixture of monochlorotriazine type reactive dyes and various dye auxiliary chemicals at typical concentrations encountered in exhausted reactive dyebath liquors. A525 (color), UV280 (aromaticity) and TOC removal rates were assessed to screen the most appropriate oxidative process in terms of reactive dyebath effluent treatment. Special emphasis was laid on the effect of reaction pH and applied oxidant (O3, H2O2) dose on the observed reaction kinetics. It was established that the investigated AOPs were negatively affected by the Na2CO3 content (= 867 mg/L) which is always present at high concentrations in dychouse effluents since it is applied as a pH buffer and dye fixation agent during the reactive dyeing process. The ozonation reaction exhibited almost instantaneous decolorization kinetics and a reasonable TOC reduction rate. It appeared to be stable under the investigated advanced oxidation conditions and outranked the other studied AOPs based on the above mentioned criteria. Besides, the electrical energy requirements based on the EE/O parameter (the electrical energy required per order of pollutant removal in 1 m3 wastewater) was calculated for the homogenous AOPs in terms of decolorization kinetics. In view of the electrical energy efficiency, ozonation and H2O2/UV-C oxidation at the selected treatment conditions appear to be promising candidates for full-scale dyehouse effluent decolorization.  相似文献   
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