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61.
62.
Fast motion estimation using reliability weighted robust search   总被引:1,自引:0,他引:1  
Hill  L. Vlachos  T. 《Electronics letters》2001,37(7):418-420
The displaced frame difference (DFD) is the most commonly used search criterion in motion estimation optimisation methods. Using a simple reliability function it is possible to speed up scale estimation required when using robust influence functions and it is shown that the search also experiences speed gains  相似文献   
63.
Acute kidney injury (AKI) is a prevalent complication in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive inpatients, which is linked to an increased mortality rate compared to patients without AKI. Here we analysed the difference in kidney blood biomarkers in SARS-CoV-2 positive patients with non-fatal or fatal outcome, in order to develop a mortality prediction model for hospitalised SARS-CoV-2 positive patients. A retrospective cohort study including data from suspected SARS-CoV-2 positive patients admitted to a large National Health Service (NHS) Foundation Trust hospital in the Yorkshire and Humber regions, United Kingdom, between 1 March 2020 and 30 August 2020. Hospitalised adult patients (aged ≥ 18 years) with at least one confirmed positive RT-PCR test for SARS-CoV-2 and blood tests of kidney biomarkers within 36 h of the RT-PCR test were included. The main outcome measure was 90-day in-hospital mortality in SARS-CoV-2 infected patients. The logistic regression and random forest (RF) models incorporated six predictors including three routine kidney function tests (sodium, urea; creatinine only in RF), along with age, sex, and ethnicity. The mortality prediction performance of the logistic regression model achieved an area under receiver operating characteristic (AUROC) curve of 0.772 in the test dataset (95% CI: 0.694–0.823), while the RF model attained the AUROC of 0.820 in the same test cohort (95% CI: 0.740–0.870). The resulting validated prediction model is the first to focus on kidney biomarkers specifically on in-hospital mortality over a 90-day period.  相似文献   
64.
Cork taint, one of the most known off-flavours in wine, is usually attributed to the presence of the aromatic compound 2,4,6-trichloroanisole (2,4,6-TCA) in cork stoppers made from the bark of the cork oak, Quercus suber. There are many major chemical/biochemical pathways through which 2,4,6-TCA can be formed during cork production. The estimated incidence of cork-tainted wine bottles ranges from 2–to 7%, costing global wine industry approximately US$ 10 billion annually. During this study, a laboratory-scale system was designed and constructed, to efficiently treat cork bark and stopper samples using ozone and/or other sterilizing gases, such as steam, via sequential application of pulsed vacuum–pressure cycles. The developed physicochemical processes were studied and evaluated in order to achieve both sterilization conditions and 2,4,6-TCA removal without affecting the mechanical and bottling properties of cork. According to the results, the application of ozone alone seems to be a promising treatment method for cork barks. However, the pulsed treatment ensures both sufficient removal (99%) of both bacteria and moulds from cork stoppers when combined with ozone or steam and satisfactory deodorization of cork stoppers achieving high percentages (90%) of 2,4,6-TCA removal when combined with steam. The operating cost of each alternative process (plain or pulsed, with or without ozone and/or steam) was estimated and compared, in laboratory scale, for the selection of the most efficient process, taking into account technicoeconomical aspects.  相似文献   
65.
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Ohne Zusammenfassung Schlu? des Aufsatzes aus Heft 4 (1966) S. 101/10.  相似文献   
67.
SARS-CoV-2 currently lacks effective first-line drug treatment. We present promising data from in silico docking studies of new Methisazone compounds (modified with calcium, Ca; iron, Fe; magnesium, Mg; manganese, Mn; or zinc, Zn) designed to bind more strongly to key proteins involved in replication of SARS-CoV-2. In this in silico molecular docking study, we investigated the inhibiting role of Methisazone and the modified drugs against SARS-CoV-2 proteins: ribonucleic acid (RNA)-dependent RNA polymerase (RdRp), spike protein, papain-like protease (PlPr), and main protease (MPro). We found that the highest binding interactions were found with the spike protein (6VYB), with the highest overall binding being observed with Mn-bound Methisazone at −8.3 kcal/mol, followed by Zn and Ca at −8.0 kcal/mol, and Fe and Mg at −7.9 kcal/mol. We also found that the metal-modified Methisazone had higher affinity for PlPr and MPro. In addition, we identified multiple binding pockets that could be singly or multiply occupied on all proteins tested. The best binding energy was with Mn–Methisazone versus spike protein, and the largest cumulative increases in binding energies were found with PlPr. We suggest that further studies are warranted to identify whether these compounds may be effective for treatment and/or prophylaxis.  相似文献   
68.
69.
Between 1979 and 1989, 876 patients with non-small-cell lung carcinoma were referred to our unit for surgical treatment. One hundred forty-six patients were judged not suitable for surgical treatment on clinical, radiologic, or bronchoscopic findings. Cervical mediastinoscopy or anterior mediastinotomy (or both) showed that 151 patients had mediastinal involvement by invasion or metastases into the ipsilateral (N2 disease) or contralateral (N3 disease) superior mediastinal lymph nodes and were therefore deemed inoperable. Except for one patient who had involvement of a single nodal station at mediastinoscopy, all other patients (n = 578) undergoing thoracotomy were thought, on the basis of computed tomographic scan or mediastinal exploration (or both) not to have N2 disease. Despite our efforts to avoid surgery on patients with N2 disease, at thoracotomy routine mediastinal node dissection disclosed that 149 patients had unsuspected N2 disease. Resection was possible in 130 (87.3%) by pneumonectomy (n = 72), bilobectomy (n = 7), lobectomy (n = 49), or lesser resection (n = 2). In three patients the resection was incomplete (2.3%), but in 127 a complete resection was performed (85%). Histologic examination in these 149 patients showed that 72 tumors were squamous cell carcinoma, 54 adenocarcinoma, 14 large-cell carcinoma, and 9 of mixed type. Eight patients died in the hospital after thoracotomy. Adjuvant therapy was not used after complete resection. Complete follow-up was obtained in 134 patients and the mean follow-up period was 27.25 months (1 to 116 months). The actuarial 5-year survival for those having complete resection was 20.1%. There was a statistically significant difference favoring long-term survival in those patients with squamous cell carcinoma (p < 0.01) and those in whom only one nodal station was involved (p < 0.05). Neither the extent of resection nor the involvement of any specific nodal station influenced long-term survival. Despite rigorous preoperative investigations, routine mediastinal node dissection demonstrated mediastinal node metastasis for the first time at thoracotomy in 26% of our patients. We believe resection is justified in these patients, who have already necessarily incurred the morbidity and mortality of thoracotomy, so long as complete resection is possible.  相似文献   
70.
Recent computational advances have made it feasible to fit hierarchical models in a wide range of serious applications. In the process, the question of model adequacy arises. While model checking usually addresses the entire model specification, model failures can occur at each hierarchical stage. Such failures include outliers, mean structures errors, dispersion misspecification, and inappropriate exchangeabilities. We propose an approach which is entirely simulation based. Given a model specification and a dataset, we need only be able to simulate draws from the resultant posterior. By replicating a posterior of interest using data obtained under the model we can “see” the extent of variability in such a posterior. Then, we can compare the posterior obtained under the observed data with this medley of posterior replicates to ascertain whether the former is in agreement with them and accordingly, whether it is plausible that the observed data came from the proposed model. Many such comparisons can be run, each focusing on a different potential model failure. Focusing on generalized linear mixed models, we explore the questions of when hierarchical model stages are separable and checkable and illustrate the approach with both real and simulated data. Research supported in part by NSF SCREMS grant DMS-9506557, NSF grant DMS-9301316 and by the Natural Sciences and Engineering Research Council of Canada  相似文献   
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