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21.
The challenge to anticipate the human factors impact of introducing new technologies into a safety critical environment can be addressed in a number of ways. This paper presents a research programme that utilised both laboratory- and field-based assessments to examine the way in which datalink and freeflight may affect the communication and collaboration between pilots, air traffic controllers, and other actors and artefacts in the flightdeck-air traffic control (ATC) joint cognitive system. An overview of the results from these studies is presented, and guidance is provided as to the likely situations in which this new technology is most likely to be successfully applied. In addition, the methodological approach of combining results from field and laboratory data is discussed.  相似文献   
22.
This paper explores the potential to retrieve surface soil moisture and optical depth simultaneously for several different patches of land cover in a single pixel from dual polarization, multiangle microwave brightness temperature observations such as will be provided by, for instance, the Soil Moisture and Ocean Salinity (SMOS) mission. MICRO-SWEAT, a coupled land-surface and microwave emission model, was used in a. year-long simulation to define the patch-specific soil moisture, optical depth, and synthetic, pixel-average microwave brightness temperatures similar to those that will be provided by SMOS. The microwave emission component of MICRO-SWEAT also forms the basis of an exploratory retrieval algorithm in which the difference between (synthetic) observations of microwave brightness temperatures and modeled, pixel-average microwave brightness temperatures for different input values of soil moisture and optical depth is minimized using the shuffled complex evolution (SCE) optimization procedure. Results are presented for two synthetic pixels, one with eight patches, where only the soil moisture is retrieved, and one with five patches, where both the soil moisture and the optical depth are retrieved  相似文献   
23.
In this work, a method for the rapid synthesis of metallic microtracks on polyetherimide is presented. The method relies on the photosynthesis of silver nanoparticles on the surface of the polymer substrates from photosensitive silver chloride (AgCl), which is synthesized directly on the polyetherimide surface. The study reveals that the use of AgCl as a photosensitive intermediate accelerates the reactions leading to the formation of silver nanoparticles by up to two orders of magnitude faster than other photodecomposition schemes. The patterning can be conducted under blue light, with notable advantages over UV exposure. Polymers of significant interest to the microelectronics and 3D printing industries can be directly patterned by light using this photography‐inspired technique at throughputs high enough to be commercially advantageous. Light exposures as short as a few seconds are sufficient to allow the direct metallization of the illuminated polyetherimide surface. The results show that the silver required for the seed layer is minimal, and the later copper electroless plating results in the selective growth of conductive tracks for circuitry on the light‐patterned areas, both on flexible films and 3D printed surfaces.  相似文献   
24.
MCBEND 10 is the latest release of the general radiation transport Monte Carlo code from the ANSWERS Software Service of Serco Assurance. MCBEND is developed within a Nuclear Code Development (NCD) partnership between Serco Assurance and BNFL. The ANSWERS vision is 'to provide easy-to-use software that meets the current and emerging needs of the user community'. In the case of MCBEND, this vision focuses on the key areas of accuracy, understanding of uncertainties, efficiency and user-friendliness. MCBEND 10 is a major launch of the code with many new and enhanced features. New developments in MCBEND 10 include automatic splitting mesh generation, point energy adjoint for neutrons, calculation of uncertainty in the results due to material cross section uncertainties and a unified source facility. Enhanced features include improved temperature treatment, extended scoring of sensitivity to geometry perturbations, geometry improvements, extensions to formulae and improved user guide image. The user-friendliness of the MCBEND code has been further enhanced by recent developments to the visualisation tools, VISAGE and VISTA-RAY. Developments have been made to the three-dimensional visualisation tool, VISTA-RAY, to simplify the detailed checking of a model, with the option to use a mouse-pointer to select regions of interest for further detail and to visually highlight incorrectly defined areas. A further development to VISTA-RAY is the inclusion of the capability to overlay a representation of a user-designated set of results from a MCBEND analysis on the model. Improvements have also been made to the graphical user interface LaunchPad for submitting and controlling calculation submission, with a common user-image across all the systems. Recent enhancements to LaunchPad include a job-scheduler to simplify processing multiple tasks. A selection of the new developments in MCBEND 10, VISTA-RAY and LaunchPad will be described in this paper.  相似文献   
25.
A computer system which automatically designs steel pitched-roof portal frame buildings is described. From a minimal amount of input, the computer produces all the design calculations, estimates, drawings, and documents for a contract. Use of the system has reduced lead time and alleviated a shortage of draughtsmen. The system runs on an inhouse minicomputer.  相似文献   
26.
Shuttleworth  S. M.  De Koker  N.  Walls  R. S. 《Fire Technology》2022,58(1):133-147
Fire Technology - Shipping containers are increasingly adapted for modern modular construction of both permanent and mobile low-cost civilian-use structures, with the diversity and...  相似文献   
27.
We characterized all of the 35 aerobic taxa of the genus Staphylococcus by using an objective, self-learning system combining both whole-cell fatty acid (FA) analysis and the results of 35 biochemical tests. Isolates were compared with the type strain for each taxon to generate an FA profile library and a biochemical table of test responses. Isolates were accepted into the system if they had a similarity index of > or = 0.6 for a taxon within the FA profile library and if they were identified as the same taxon by a computer program using a probability matrix constructed from the biochemical data. These stringent criteria led to acceptance of 1,117 strains assigned to legitimate taxa. Additional FA groups were assembled from selected strains that did not meet the inclusion criteria based on the type strains and were added to the system as separate entries. Currently, 1,512 isolates have bee accepted into the system. This approach has resulted in a comprehensive table of biochemical test results and a FA profile library, which together provide a practical system for valid identifications.  相似文献   
28.
Calcium-activated potassium channels (maxi K+ channels) isolated from avian nasal salt gland cells were reconstituted into lipid bilayers and characterized. The 266 pS channel is blocked discretely by charybdotoxin from the external solution at nanomolar concentrations and by Ba2+ from the cytosolic side at micromolar concentrations. Fast tetraethylammonium (TEA) block is seen as apparent reductions in amplitude of the unitary currents. From the extent of the reductions, TEA binding affinity was calculated to be 0.16 mM from the external solution and 37 mm from internal solution. The overall channel properties conform to those of maxi K+ channels in other epithelial tissues. The calcium sensitivity of the channel was found to be variable from channel to channel, extending over a wide range of concentrations from 1 to 1,000 microM. Examination of the pooled calcium titration curves, revealed that these curves are grouped into five clusters, and the probability distribution of the clusters matches a binomial distribution. The Hill coefficient derived from the titration curves varies from 1 to 5 and is linearly correlated to calcium binding with a slope of 1 per 10-fold change in Kd. Clustered titration curves with such a characteristic suggest that the gating components and the calcium binding sites of the maxi K+ channels in the avian nasal gland are hetero-tetrameric and may result from random mixing of two distinct subunits possessing high and low calcium sensitivities, respectively.  相似文献   
29.
Chronically sun-exposed or photodamaged human skin is characterized by a number of clinical features, including wrinkles. However, little is known about the molecular mechanisms that underlie these features. We investigated the hypothesis that the mechanism of wrinkle formation may involve loss of anchoring fibrils, composed mainly of collagen VII, which are important in maintaining dermal-epidermal junction integrity. Ten volunteers with moderate to severe photodamage of dorsal forearm skin were recruited to the study. Using immunohistochemistry, transmission electron microscopy and in situ hybridization, we compared collagen VII protein and mRNA content of photodamaged forearm skin with that of sun-protected hip and upper inner arm skin from the same subjects. Numbers of anchoring fibrils per linear microns of basement membrane (mean +/- SEM) were significantly lower in photodamaged skin (1.79 +/- 0.10) as compared with sun-protected hip (2.28 +/- 0.11) and upper inner arm skin (2.21 +/- 0.10) (P < 0.01), and similarly keratinocyte expression of collagen VII mRNA, quantitated as number of positively stained keratinocytes per high power field, was significantly reduced in photodamaged skin (6.3 +/- 2.5) as compared with sun-protected hip (20.0 +/- 5.6) and upper inner arm skin (17.7 +/- 4.9) (P < 0.001). Semiquantitative assessment of immunohistochemical staining for collagen VII showed a non-significant reduction in photodamaged skin as compared with sun-protected skin. We propose that reduced content of collagen VII in photodamaged skin contributes to wrinkle formation by weakening the bond between the dermis and epidermis.  相似文献   
30.
A novel culture system is reported in which pig preantral follicles (< 300 microm in diameter) with an intact thecal cell layer were isolated and cultured in a serum-free medium for up to 30 days. The medium supported follicle culture after isolation, while maintaining both somatic cell and oocyte viability. Follicles were cultured in groups (n = 3 per group) on collagen-coated wells for 16 days, during which they retained a three-dimensional structure, maintained oocyte viability and increased in diameter and number of somatic cells. Follicle culture for 30 days resulted in a further increase in number of cells, oocyte viability was maintained, and a significant increase in follicle diameter was observed (P < 0.001), with 29% of follicles forming an antrum. Follicles synthesized measurable quantities of progesterone (168 pg per 100 microl per 48 h; no significant increase with time) and increasing quantities of oestradiol (136 pg per 100 microl per 48 h; P < 0.001 with time). Further supplementation of the medium with 100 micromol testosterone l(-1) at day 28 resulted in a significant increase in oestradiol secretion by both antral (P < 0.01) and preantral follicles (P < 0.05). Culture over 30 days in medium with 10(-10) mol angiotensin II l(-1) and further supplementation at day 28 with 100 micromol testosterone l-1 also increased oestradiol synthesis (P < 0.001). These results show that viable preantral follicles may be cultured for extended periods, and indicate that the possible role of angiotensin II in folliculogenesis and steroidogenesis in early development of pig follicles requires further investigation.  相似文献   
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