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We describe a content-based audio classification algorithm based on novel multiscale spectro-temporal modulation features inspired by a model of auditory cortical processing. The task explored is to discriminate speech from nonspeech consisting of animal vocalizations, music, and environmental sounds. Although this is a relatively easy task for humans, it is still difficult to automate well, especially in noisy and reverberant environments. The auditory model captures basic processes occurring from the early cochlear stages to the central cortical areas. The model generates a multidimensional spectro-temporal representation of the sound, which is then analyzed by a multilinear dimensionality reduction technique and classified by a support vector machine (SVM). Generalization of the system to signals in high level of additive noise and reverberation is evaluated and compared to two existing approaches (Scheirer and Slaney, 2002 and Kingsbury et al., 2002). The results demonstrate the advantages of the auditory model over the other two systems, especially at low signal-to-noise ratios (SNRs) and high reverberation.  相似文献   
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The authors argue that the current state of applied data-based test analytic practice is unstructured and unmethodical due in large part to the fact that there is no clearly specified, widely accepted test analytic framework for judging the performances of particular tests in particular contexts. Drawing from the extant test theory literature, they propose a rationale that may be used in data-based test analysis. The components of the proposed test analytic framework are outlined in detail, as are examples of the framework as applied to commonly encountered test evaluative scenarios. A number of potential extensions of the framework are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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This study of college students (N?=?464) examined the association between adaptive and maladaptive dimensions of perfectionism and 2 mental health outcomes (self-esteem and depression). Confirmatory factor analysis was used to develop and assess the measurement model used in this study. Structural equations modeling was used to test a mediational model derived from prior theory and research. Analyses supported the existence of 2 perfectionism factors. Path models revealed that adaptive perfectionism was not directly or indirectly (through self-esteem) associated with depression. Maladaptive perfectionism was negatively associated with self-esteem and positively associated with depression. Self-esteem also buffered the effects of maladaptive perfectionism on depression. Distinguishing adaptive from maladaptive perfectionism is discussed in the context of recommendations for practice and future research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Developing sensors for in vivo chemical monitoring is a daunting challenge. An alternative approach is to couple sampling methods with online analytical techniques; however, such approaches are generally hampered by lower temporal resolution and slow analysis. In this work, microdialysis sampling was coupled with segmented flow electrospray ionization mass spectrometry (ESI-MS) to perform in vivo chemical monitoring. The use of segmented flow to prevent Taylor dispersion of collected zones and rapid analysis with direct ESI-MS allowed 5 s temporal resolution to be achieved. The MS "sensor" was applied to monitor acetylcholine in the brain of live rats. The detection limit of 5 nM was sufficient to monitor basal acetylcholine as well as dynamic changes elicited by microinjection of neostigmine, an inhibitor of acetycholinesterase, that evoked rapid increases in acetycholine and tetrodotoxin, a blocker of Na(+) channels, that lowered the acetylcholine concentration. The versatility of the sensor was demonstrated by simultaneously monitoring metabolites and infused drugs.  相似文献   
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A convenient method for passivating and functionalizing stainless steel is described. Several methods of coating stainless steel (SS) samples with silica were investigated and of these methods, a thin (less than 15 nm thick) layer of silica created by atomic layer deposition (ALD) was found to give superior performance in electrochemical testing. These interfaces were then used as a platform for further functionalization with molecules of biological interest. Specifically, the SS samples were functionalized with biologically significant carbohydrates [N-acetyl-D-glucosamine (GlcNAc) and D-galactose (Gal)] that contain trialkoxysilane derivatives as chemical handles for linking to the surface. The presence and biological availability of these moieties on the silica coated SS were confirmed by XPS analysis and an enzyme-linked lectin assay (ELLA) using complementary lectins that specifically recognize the surface-bound carbohydrate. This method has the potential of being adapted to the functionalization of stainless steel biomedical implants with other biologically relevant carbohydrates.  相似文献   
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Two of the 43 Shuttle Imaging Radar (SIR-B) experiments carried out from the 41-G shuttle mission in 1984 involved a 2600-km swath across the Canadian Shield, with the objectives of studying the structure of province boundaries and developing techniques for the geologic use of orbital radar. Despite degraded single incidence angle imagery resulting from system problems, valuable experience has been obtained with data over a test site near Bancroft, Ontario. It has been found that even subdued glaciated topography can be effectively imaged, variations in backscatter being caused by variations in local incidence angle rather than shadowing. It has been demonstrated that small incidence angles are more sensitive to topography than large angles. Backscatter is extremely sensitive to look direction, topographic features nearly normal to the illumination being highlighted, and those nearly parallel to it being suppressed. It is concluded that orbital radar can provide a valuable tool for geologic studies of the Canadian Shield and similar areas, if suitable look angles and at least two look directions can be utilized for each area.  相似文献   
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Seventy patients with adolescent idiopathic right thoracic scoliosis had full assessment of their pulmonary function using a computerised pulmonary function system. Their mean age at evaluation was 13.8 years. The following measurements were obtained from anteroposterior and lateral standing and antero-posterior supine bending radiographs: lateral curvature, vertebral rotation, kyphosis, maximum sterno-vertebral distance and apical rib-vertebral angles. Using the above measurements, the flexibility of curve, vertebral rotation and rib-vertebral angle asymmetry were calculated. Patients were classified into three groups on the basis of their predicted vital capacity, to determine whether radiological features of deformity can help identify patients with compromised pulmonary function. The mean Cobb angle and vertebral rotation for the 70 patients were 50 degrees (range 35-100 degrees) and 22 degrees (range 1-44 degrees) respectively. The mean flexibility of curve and vertebral rotation were 52% and 49% respectively. Mean thoracic kyphosis was 25 degrees, ranging from -7 to 55 degrees. Of the patients with Cobb angle less than 90 degrees, 71% had vital capacity less than 80% of predicted values, and of these, 18% had marked compromise of vital capacity (less than 60% of predicted values). Mean values of Cobb angle, vertebral rotational flexibility, kyphosis, rib-vertebral angle asymmetry (in standing as well as supine bending radiographs) differed significantly between patients with more than 80% of predicted vital capacity and those with 60% or less of predicted values. Radiological features indicative of better pulmonary function were: rotational flexibility exceeding 55%, rib-vertebral angle asymmetry (standing) less than 25 degrees and kyphosis greater than 15 degrees. Two deformity parameters--that give a better prediction of pulmonary function than the widely used Cobb angle, vertebral rotational flexibility and rib-vertebral angle asymmetry--were identified in this study.  相似文献   
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The so-called "problem of theoretical terms" rests on the notion that the signifiers of theoretical concepts cannot be completely defined for the reason that their referents are beyond the boundaries of human perception and/or cognition. Empirical realism is a scientific tradition that was born, in part, out of a dissatisfaction with the positivist treatment of theoretical terms. Empirical realists generally conceive of theoretical terms as playing an essential role in scientific activity, giving it its explanatory force, as it is such terms which denote the real, but unobservable, hypothetical entities which are thought to underlie those observable phenomena that the scientist seeks to explain. Despite certain consistencies that run throughout realist thought, there also exist a number of points of divergence among empirical realists. These are examined along with 2 different and contrasting traditions of empirical realism within psychological science. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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