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81.
Word recognition, semantic priming, and cognitive impenetrability research have used signal detection theory (SDT) measures to separate perceptual and postperceptual processes. In the D. Norris (1986) checking model and model simulation (D. Norris, 1995), priming alters only postperceptual word decision criteria: Stimulus-related priming reduces uncertainty, increasing sensitivity; stimulus-unrelated priming increases false alarms more than hits, reducing sensitivity. This work is cited as strong evidence that criterion changes can alter perceptual sensitivity and that SDT is inappropriate for investigating complex cognitive processes. The authors' current SDT ideal observer analysis of the model demonstrates that related priming does not directly alter sensitivity and that unrelated priming increases only false-alarm rate, reducing sensitivity. This analysis provides new perspectives on SDT concepts of complex decision processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
Thymidylate synthase (TS) is a key enzyme in the biosynthesis of thymidine. The use of TS inhibitors in cancer chemotherapy suffers from resistance development in tumors through upregulation of TS expression. Autoregulatory translation control has been implicated with TS overexpression. TS binding at its own mRNA, which leads to sequestration of the start codon, is abolished when the enzyme forms an inhibitor complex, thereby relieving translation suppression. We have used the protein‐binding site from the TS mRNA in the context of a bicistronic expression system to validate targeting the regulatory motif with stabilizing ligands that prevent ribosomal initiation. Stabilization of the RNA by mutations, which were studied as surrogates of ligand binding, suppresses translation of the TS protein. Compounds that stabilize the TS‐binding RNA motif and thereby inhibit ribosomal initiation might be used in combination with existing TS enzyme‐targeting drugs to overcome resistance development during chemotherapy.  相似文献   
83.
While display designers tend to agree that the communication of large amounts of quantitative information calls for the use of graphs, there is less consensus about whether graphs should be used for small, summarized data sets. In the present study, three groups of 16 subjects viewed 11 sets of time series data presented as tables, bar charts, or line graphs. Data sets varied in size (4, 7, or 13 values) and complexity (number and type of departures from linearity). Subjects provided written interpretations of each of the data sets, and these interpretations were scored for (1) overall number of propositions pertaining to the data set as a whole (global content), (2) number of propositions describing relations within a subset of the data (local content), and (3) number of references to specific data values (numeric content). For the larger (7- and 13-point) data sets, interpretations based on bar charts included the greatest overall global content, but line graph interpretations proved to be most sensitive to the actual information content (complexity) of the data sets. The greater sensitivity of the line graphs was still obtained with four-point data sets; however, this advantage was greater for men than for women. For data sets of all sizes, but especially for the smallest sets, gender differences in interpretation content were obtained. These differences are discussed within the context of more general individual differences presumed to exist in graphreading strategies.  相似文献   
84.
Fresh bovine manure was mechanically incorporated into loamy sand and silty clay loam Wisconsin soils in April 2004. At varying fertilization-to-planting intervals, radish, lettuce, and carrot seeds were planted; crops were harvested 90, 100, 110 or 111, and 120 days after manure application. As an indicator of potential contamination with fecal pathogens, levels of Escherichia coli in the manure-fertilized soil and presence of E. coli on harvested vegetables were monitored. From initial levels of 4.0 to 4.2 log CFU/g, E. coli levels in both manure-fertilized soils decreased by 2.4 to 2.5 log CFU/g during the first 7 weeks. However, E. coli was consistently detected from enriched soil samples through week 17, perhaps as a result of contamination by birds and other wildlife. In the higher clay silty clay loam soil, the fertilization-to-planting interval affected the prevalence of E. coli on lettuce but not on radishes and carrots. Root crop contamination was consistent across different fertilization-to-harvest intervals in silty clay loam, including the National Organic Program minimum fertilization-to-harvest interval of 120 days. However, lettuce contamination in silty clay loam was significantly (P < 0.10) affected by fertilization-to-harvest interval. Increasing the fertilization-to-planting interval in the lower clay loamy sand soil decreased the prevalence of E. coli on root crops. The fertilization-to-harvest interval had no clear effect on vegetable contamination in loamy sand. Overall, these results do not provide grounds for reducing the National Organic Program minimum fertilization-to-harvest interval from the current 120-day standard.  相似文献   
85.
Commercial spectrophotometers typically use absorption-based wavelength calibration reference materials to provide wavelength accuracy for their applications. Low-mass fractions of holmium oxide (Ho2O3) in dilute acidic aqueous solution and in glass matrixes have been favored for use as wavelength calibration materials on the basis of spectral coverage and absorption band shape. Both aqueous and glass Ho2O3 reference materials are available commercially and through various National Metrology Institutes (NMIs). Three NMIs of the North American Cooperation in Metrology (NORAMET) have evaluated the performance of Ho3-(aq)-based Certified Reference Materials (CRMs) under "routine" operating conditions using commercial instrumentation. The study was not intended to intercompare national wavelength scales but to demonstrate comparability of wavelength measurements among the participants and between two versions of the CRMs. It was also designed to acquire data from a variety of spectrophotometers for use in a NIST study of wavelength assignment algorithms and to provide a basis for a possible reassessment of NIST-certified Ho3+(aq) band locations. The resulting data show a substantial level of agreement among laboratories, instruments, CRM preparations, and peak-location algorithms. At the same time, it is demonstrated that the wavelength comparability of the five participating instruments can actually be improved by calibrating all of the instruments to the consensus Ho3+(aq) band locations. This finding supports the value of absorption-based wavelength standards for calibrating absorption spectrophotometers. Coupled with the demonstrated robustness of the band position values with respect to preparation and measurement conditions, it also supports the concept of extending the present approach to additional NMIs in order to certify properly prepared dilute acidic Ho2O3 solution as an intrinsic wavelength standard.  相似文献   
86.
Embellishing simple graphs by adding perspective, 'the 3D look, has become increasingly commonplace with the ready availability of graphics software. However, the effect of adding such decorative depth on the comprehension and recall of the graph's message has received little attention. The present study evaluated performance on such common graphical formats as line graphs, bar charts and pie charts constructed with and without the 3D look. When subjects were asked to make relative magnitude estimations, only the 3D line graphs resulted in reliable performance decrements. Likewise, information presented in 3D line graphs was remembered less accurately than information presented in 2D line graphs. For the estimation of global trends, both 3D line graphs and bar charts were used more quickly than 2D formats, but this speed was obtained at the expense of accuracy. For a trend classification task involving more focused processing, 3D line graphs and bar charts were associated with an overall performance decrement when compared with their 2D counterparts. Finally, the use of 3D designs, in addition to modifying performance, may influence the attitudes formed by subjects toward the information presented in the graphs.  相似文献   
87.
Kohonen's self-organizing map (SOM) network maps input data to a lower dimensional output map. The extended SOM network further groups the nodes on the output map into a user specified number of clusters. Kiang, Hu and Fisher used the extended SOM network for market segmentation and showed that the extended SOM provides better results than the statistical approach that reduces the dimensionality of the problem via factor analysis and then forms segments with cluster analysis. In this study, we examined the effect of sample size on the extended SOM compared to that on the factor/cluster approach. Two sampling schemes, one with random sampling and the other one with proportionate sampling were used. Comparisons were made using the correct classification rates between the two approaches at various sample sizes. Unlike statistical models, neural networks are not dependent on statistical assumptions. Thus, the results for neural network models are stable across sample sizes but sensitive to initial weights and model specifications.  相似文献   
88.
Pediatric mastocytosis is a heterogeneous disease characterized by accumulation of mast cells in the skin and less frequently in other organs. Somatic or germline mutations in the KIT proto-oncogene are detected in most patients. Cutaneous mastocytosis is the most common form of the disease in children. In the majority of cases, skin lesions regress spontaneously around puberty. However, in few patients, mastocytosis is not a self-limiting disease, but persists into adulthood and can show signs of systemic involvement, especially when skin lesions are small-sized and monomorphic. Children with mastocytosis often suffer from mast cell mediator-related symptoms. Severe hypersensitivity reactions can also occur, mostly in patients with extensive skin lesions and blistering. In a substantial number of these cases, the triggering factor of anaphylaxis remains unidentified. Management of pediatric mastocytosis is mainly based on strict avoidance of triggers, treatment with H1 and H2 histamine receptor blockers, and equipment of patients and their families with epinephrine auto-injectors for use in severe anaphylactic reactions. Advanced systemic mastocytosis occurs occasionally. All children with mastocytosis require follow-up examinations. A bone marrow investigation is performed when advanced systemic mastocytosis is suspected and has an impact on therapy or when cutaneous disease persists into adulthood.  相似文献   
89.
A transformation-induced plasticity phenomenon in Fe65(CoCrMnNi)35 medium-entropy alloy was investigated. According to the X-ray diffraction patterns, the as-cast specimen contains a single-phase face-centered cubic (fcc), while low-temperature annealing at 500 °C and 600 °C leads to the introduction of a body-centered cubic (bcc) phase as a secondary phase. Further increment of the annealing temperature to above 700 °C eliminates the bcc phase, and the microstructure was found to contain a single-phase fcc. At 20% true strain, an fcc-to-bcc phase transformation is observed; whereas, at 28% true strain, an fcc-to-hcp phase transformation takes place as an additional deformation mechanism. This strain-induced phase transformation phenomenon leads to improved tensile properties of this alloy.  相似文献   
90.
The winemaking process produces a large volume of wastewater with highly variable characteristics. Methods in place to manage winery wastewater (WWW) vary, with some wineries treating their WWW on-site, while others direct the WWW to municipal wastewater treatment plants (WWTPs). Despite the significant presence and growth of the wine industry in the Niagara Region of Ontario, Canada, few data are available regarding the characteristics and treatment of WWW in this geographic region. This work presents a comprehensive review of full-scale treatment methods currently in place to manage and treat WWW at 53 wineries in the Niagara Region. The most common type of on-site treatment is the constructed wetland process, providing overall removal rates of >98% for chemical oxygen demand (COD) and >98% for total suspended solids (TSS) for the combined treatment of WWW and site-generated sanitary sewage. Subsurface effluent discharge is the most widely used disposal strategy, while larger systems treating WWW alone also reuse the effluent for vineyard irrigation. The construction and operation of on-site treatment systems at wineries does not address all WWW treatment needs, requiring a portion of the WWW to be co-treated at WWTPs. While full-scale operating data indicate that anaerobic co-digestion with municipal sludges is effective (89% COD removal), the co-digestion capacity is limited. Co-treatment in the municipal WWTPs' liquid treatment train leads to negative operational and performance impacts. No efficient WWW co-treatment options, viable in the long-term, are currently available at municipal WWTPs. Improved co-treatment strategies are required to address WWW treatment needs in the Niagara Region.  相似文献   
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