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991.
A sporting event game speed analysis and tracking system—Scout is presented in this paper. Common computer vision and pattern
recognition methods, such as background subtraction, connected components labelling, morphology filtering, etc., are used
for segmenting and tracking moving objects. A new vanishing-points-based method is proposed for the mapping between the screen
(image) and physical (field) coordinate systems. The system is designed to evaluate football players’ performance and skills
from the recorded training camps’ footages. The tracking results and performance analysis of real football training camps’
video clips are presented. 相似文献
992.
LaBar Kevin S.; Gitelman Darren R.; Parrish Todd B.; Kim Yun-Hee; Nobre Anna C.; Mesulam M. -Marsel 《Canadian Metallurgical Quarterly》2001,115(2):493
Functional magnetic resonance imaging (fMRI) was used to determine whether visual responses to food in the human amygdala and related corticolimbic structures would be selectively altered by changes in states of hunger. Participants (19–44 yr olds) viewed images of motivationally relevant (food) and motivationally irrelevant (tool) objects while undergoing FMRI in alternately hungry and satiated conditions. Food-related visual stimuli elicited greater responses in the amygdala, parahippocampal gyrus, and anterior fusiform gyrus when participants were in a hungry state relative to a satiated state. The state-dependent activation of these brain structures did not generalize to the motivationally irrelevant objects. These results support the hypothesis that the amygdala and associated inferotemporal regions are involved in the integration of subjective interoceptive states with relevant sensory cues processed along the ventral visual stream. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
A mid-Holocene buried organic layer 10 to 60 cm thick is present along the Lake Michigan shoreline in southeastern Wisconsin. Named the Southport forest bed for its location in Kenosha County, the unit has yielded abundant wood specimens, including large logs, branches, twigs, stumps, and root material. Roots of truncated in situ oak (Quercus) and elm (Ulmus) trees extend into the underlying till of the late Wisconsin Oak Creek Formation. Nearshore lacustrine sand above the organic layer contains abundant driftwood, overlain by 2 to 3 m of cross-bedded dune sand. More than 50 wood samples have been identified; the assemblage is that of a mixed hardwood forest dominated by oak (Quercus) and hickory (Carya), which account for about 60% of the assemblage. Although the site has been mostly concealed for many years, it was beautifully exposed in the 1960s and early 1970s, when it was initially studied by Phil Sander, who discovered the site and documented it with field notes and numerous photographs. Here we report several new (unpublished) radiocarbon dates and details of the stratigraphy and arboreal flora. Radiocarbon dates suggest that the Southport forest probably lived for 900–1000 14C years, possibly longer, reaching its climax at about 5300 B.P. The site is of particular importance because of its proximity to the Nipissing shoreline and provides a significant point on the Nipissing transgression time curve. The unusually large number of identified specimens affords an accurate evaluation of the warm and relatively dry climate that characterized the southern Great Lakes region during the mid-Holocene. 相似文献
994.
Asad Khan Tod Schneider Erica Montbach Donald J. Davis Nick Miller Duane Marhefka Todd Ernst J. William Doane 《Journal of the Society for Information Display》2008,16(2):245-250
Abstract— Highly flexible layered full‐color cholesteric displays fabricated using ultra‐thin substrates with encapsulation through the phase‐separation approach is reported. Recent progress of the state of the art of cholesteric display technology will be discussed as well. 相似文献
995.
Minds and Machines - A working assumption that processes of natural and cultural evolution have tailored the mind to fit the demands and structure of its environment begs the question: how are we... 相似文献
996.
This study used anatomical cues to suggest a functional dissociation between the roles of the entorhinal cortex and the hippocampus in learning. The authors proposed that the highly convergent inputs to the entorhinal cortex indicate this region may be particularly important for selecting or compressing information. This hypothesis was tested in rabbits (Oryctolagus cunniculus) trained on an associative learning task that is a common index of stimulus selection. In this task, known as latent inhibition, preexposure to a stimulus (such as a tone) leads to slowed learning when the same tone is subsequently paired with an outcome (such as an airpuff to the eye). As hypothesized, rabbits with neurotoxic lesions of the entorhinal cortex failed to show slowed learning following preexposure (no latent inhibition) and learned the association faster than control rabbits. In contrast, hippocampal-lesioned animals showed normal (slowed) learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
BACKGROUND: Little is known about the effects of walking in high heels on joints in the legs. Since osteoarthritis of the knee is twice as common in women as in men, we investigated torques (forces applied about the leg joints) of women who wore high-heeled shoes. METHODS: We studied 20 healthy women who were comfortable wearing high-heeled shoes. The women walked with their own high-heeled shoes and barefoot. Data were plotted and qualitatively compared; major peak values for high-heeled and barefoot walking were statistically compared. Bonferroni adjustment was made for multiple comparisons. FINDINGS: Measurement showed increased force across the patellofemoral joint and a greater compressive force on the medial compartment of the knee (average 23% greater forces) during walking in high heels than barefoot. INTERPRETATION: The altered forces at the knee caused by walking in high heels may predispose to degenerative changes in the joint. 相似文献
998.
999.
Clot removal at early surgery has been reported to be clinically effective for the prevention of cerebral vasospasm following subarachnoid hemorrhage (SAH) due to rupture of an intracranial aneurysm. We examined the most efficacious timing of mechanical clot removal on pharmacological responses in a monkey SAH model. Cynomolgus monkeys (Macaca fascicularis) were randomized into five groups: sham-operated, clot removal in which the clot was removed 48, 72, or 96 h after SAH, and clot groups. An autologous blood clot was placed around the bilateral major cerebral arteries after craniectomy to mimic the hemorrhage. Seven days after the SAH, proximal and successively distal parts of the middle cerebral arteries were cut into rings for isometric tension measurement. The contractile responses to potassium chloride, 5-hydroxytryptamine, norepinephrine, adenosine triphosphate, prostaglandin F20, and hemoglobin were greater in the proximal parts than in the distal parts in each group. Compared with the sham-operated group, the responses of the clot-removal and clot groups to the drugs were progressively attenuated. The maximum responses to 5-hydroxytryptamine in the proximal parts and to adenosine triphosphate in the distal parts started to decrease, significantly, in the clot-removal group 48 h after SAH, while most of the responses to the other agonists began to decrease in the clot-removal groups later than 72 h after SAH. These results suggest that the attenuation of cerebrovascular contractile responses 7 days after SAH is pharmacologically inevitable, even if the clot is removed as early as 48 h after the SAH. Clot removal may thus be recommended within 48h after SAH to ameliorate the severity of cerebral vasospasm following SAH. 相似文献
1000.