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71.
Computerised biometric systems are automated methods of verifying or recognising the identity of a user on the basis of some physiological characteristic, like a fingerprint or some aspects of behaviour such as keystroke patterns. Behaviourally based biometric systems include signature, speaker and keystroke verification. The investigation of psychological factors which might impact on the efficiency of a behavioural biometric computer security monitoring system has to our knowledge not been conducted. Of particular concern in the present paper are the potential effects of state anxiety on individual's physiological and performance responses. It is suggested that in a behaviourally based biometric computer security monitoring system, state anxiety may have sufficient effects to alter typical physiological and performance responses, resulting in an increased risk of security challenges, interruption of work-flow and resultant poor performance. It is also proposed that behaviourally based biometric systems may have the potential to be used as electronic performance monitoring systems, and typical responses to such systems need to be examined when developing and implementing any behaviourally based biometric security system. 相似文献
72.
Specialist insect herbivores that sequester allelochemicals from their host plants may be unpalatable to potential predators. However, the host-plant species used may determine the degree of palatability. Spiders, including members of the family Lycosidae, are important predators of invertebrate prey. We fed buckeye caterpillars, Junonia coenia (Nymphalidae), reared on Plantago lanceolata (containing high levels of iridoid glycosides) or P. major (containing low levels of iridoid glycosides) to prairie wolf spiders, Lycosa carolinensis (Lycosidae), to determine whether the spiders found insects that sequester iridoid glycosides unpalatable. In a field experiment, spiders ate caterpillars reared on P. major significantly more often than caterpillars reared on P. lanceolata, although they attacked equal numbers of both types of prey. Spiders that bit caterpillars behind their heads or along the middle of their backs prevented caterpillars from implementing deterrent defensive strategies such as regurgitating or defecating. In a laboratory experiment, we presented spiders with P. lanceolata-reared and P. major-reared caterpillars simultaneously for eight consecutive trials. Spiders consumed P. major-reared buckeyes significantly more often than P. lanceolata-reared caterpillars. We found no evidence that the spiders learned to avoid the unpalatable prey. 相似文献
73.
M. Deane Bowers 《Journal of chemical ecology》1984,10(11):1567-1577
Larvae of the buckeye,Junonia coenia (Nymphalidae) feed primarily on plants in four families: Scrophulariaceae, Plantaginaceae, Verbenaceae, and Acanthaceae. These plant families have in common the presence of a group of plant secondary compounds, the iridoid glycosides. Larvae were reared on three plant species and two artificial diets, one with and one without iridoid glycosides.Larvae grew poorly and had low survivorship on the artificial diet without iridoid glycosides, while growth and survival on the artificial diet with iridoid glycosides was comparable to that on plants. Choice tests using artificial diets with and without iridoid glycosides showed that larvae: (1) chose diets with iridoid glycosides (in the form of a crude extract or pure compound) over a diet without; (2) showed no preference between the diet with the crude extract and that with pure iridoid glycoside, and (3) preferred the artificial diet with ground leaves of the host plant,Plantago lanceolata, over the diet with pure iridoid glycosides. The artificial diet that larvae had been reared on prior to these tests had no effect on subsequent larval preferences in the choice tests. 相似文献
74.
Damage by larvae of the buckeye butterfly (Junonia coenia) resulted in removal of 15–25% of Plantago lanceolata leaf area. Plants grown under high nutrients were larger than those grown under low nutrients. Twenty-eight days after herbivory, plants grown under high nutrients were still larger than those grown under low nutrients, and plants exposed to herbivores were significantly smaller than those not exposed to herbivores, regardless of the nutrient treatment. Damage by larvae also increased the iridoid glycoside content in the leaves and reproductive tissues of these Plantago lanceolata relative to undamaged controls. Whether damaged or undamaged, the iridoid glycoside content of P. lanceolata was highest in the reproductive tissues and lowest in the roots. Although initial concentrations of iridoid glycosides were significantly higher in plants grown under low nutrient conditions than in plants grown under high nutrient conditions, nutrient availability did not alter the phytochemical response of plants to herbivore damage. These results provide additional support for the defensive role of the iridoid glycosides in Plantago lanceolata by demonstrating that phytochemical variation is not always an incidental effect of nutrient stress but can be a direct response to damage by herbivores. 相似文献
75.
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77.
Aikins Deane E.; Hazlett-Stevens Holly; Craske Michelle G. 《Canadian Metallurgical Quarterly》2001,69(6):904
The authors suggest that D. Westen and K. Morrison's (2001) meta-analysis of treatment (see record 2001-05666-001) is critically limited in the consideration of measurement and mechanisms of therapeutic change. The measures included in the analysis fail to represent a comprehensive coverage of the domains within which change is expected. Moreover, they do not measure the theoretically derived constructs currently conceived as being central to each disorder. Further, the particular meta-analytical approach taken prohibits evaluation of the treatment components responsible for change. The authors reviewed the most recent data on comorbidity as an issue of treatment efficacy and generalizability, proffer an interpretation for the difference in outcome results across the 3 diagnostic groups, and discuss internally valid methodologies for the bridging from research to clinical practice. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
78.
A full-scale simulation-aided ESD design methodology was used to design a group of NMOS ESD protection units. Silicon results match the simulation data quite well. Both simulation and measurement data show good ESD performance uniformity across NMOS poly finger length and finger number in ladder structures in a large range. Optimal layout pattern for ladder structures was obtained with the aid of simulation. 相似文献
79.
Deane K. Smith Ron Jenkins 《Journal of research of the National Institute of Standards and Technology》1996,101(3):259-271
The Powder Diffraction file has been the primary reference for Powder Diffraction Data for more than half a century. The file is a collection of about 65 000 reduced powder patterns stored as sets of d/I data along with the appropriate crystallographic, physical and experimental information. This paper reviews the development and growth of the PDF and discusses the role of the ICDD in the maintenance and dissemination of the file. 相似文献
80.
Deane Simpson 《Architectural Design》2016,86(4):86-91
With over 110,000 inhabitants , The Villages is the world's largest retirement community. Its numerous distinct ‘villages’, surrounded by artificial landscaping and golf courses and served by three ‘downtowns’, cater to those who crave the idealised rural life of times gone by while also offering the convenience and stimulation of the modern metropolis. Deane Simpson , leader of the Master's programme in Urbanism and Societal Change at the Royal Danish Academy of Fine Arts School of Architecture, investigates. 相似文献