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As marketing communications proliferate, the ability to target the right audience for a message is of ever-increasing importance. Audience targeting practices for mass media, both in research and in industry, have tended to emphasize demographics, behavior, and other characteristics of customer groups as the bases for matching communications to audiences. These approaches overlook the opportunity to leverage the nature of advertising content, by automatically matching advertisement content to appropriate media channels and target audience. We model the semantic and sentiment content of advertisements with 103 variables. Based on these variables, a neural network classifier is used to assign advertisements to groups that represent different media channels. In its ability to classify unseen advertisements, the model outperforms the classification result generated by a random model, by 100–300%. This method also enables us to identify and describe divergent advertisement characteristics, by industry.  相似文献   
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A semiautomated method for the measurement of serum total cholesterol, based on the Abell-Kendall procedure, is described by which 100 to 140 samples may be analyzed in duplicate per day. The method was made possible by the development of a Liebermann color reagent which is stable for 8 hr. Mechanized pipetting units are used to measure all reagents and the 0.1 ml samples of serum. One analyst can analyze 60 samples in duplicate per day. Determinations are carried out on an assembly line basis so that 2 analysts can analyze more than twice as many samples as can one analyst. Representative data collected over a period of 2 years for the analysis of routine samples showed that the standard deviation for duplicates, randomized over 6-day periods, ranged from 2.7 to 3.0 mg% after repeating the analysis of the 6 to 8% of samples whose duplicates differed by more than 9 mg%.  相似文献   
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Expanding on research showing that radio-frequency-induced lesions of the habenular complex disrupt the hormonal onset of maternal behavior in rats, the authors explored the importance of neurons in the lateral (Lhb) subdivision of the habenular complex for the onset of maternal behavior. On Day 12 of pregnancy, bilateral cytotoxic lesions were produced in the Lhb with kainic acid or, as a control, just dorsal in the medial hippocampus. A 3rd group had radio-frequency-induced Lhb and medial (Mhb) lesions. On Day 16 of pregnancy, Ss were hysterectomized–ovariectomized, given estradiol, and tested 48 hrs later for 10 days. Neuroanatomical tracing with fluoro-gold was then used to directly quantify the extent and location of Lhb neuron loss and to verify that Mhb neurons were intact. Cytotoxic lesions of the entire Lhb prevented the onset of all components of maternal behavior compared with controls. Results show that neurons in the Lhb, not the Mhb, are important for onset of maternal behavior in rats. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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SUMMARY

This article will address the problems of developing and implementing a federated searching system and the involvement by reference staff expected to use, teach, and promote it. Implementation of federated search usually begins with developing basic technical functionality and then progresses to increased participation by public service librarians and system users in order to refine searching interfaces and content retrieval mechanisms and display. From the reference perspective, some impediments occurred in utilizing the federated search system since reference staff did not participate in the development of the product; since there was resistance to the concept of the product by instructional staff; and since performance inconsistencies and the use of a complex interface hampered functionality. This article will address the evolution of organizational stakeholder participation in the development of the federated search system at the Loyola Notre Dame Library.  相似文献   
26.
Scarce surface water resources have led farmers to use groundwater heavily for irrigation in the Murray-Darling Basin of Australia. Saline groundwater is emerging as an alternative source of water for irrigation. This study examines the potential use of saline groundwater for a range of crops. Among cropping groups modelled, oilseeds and grain crops are considerably tolerant to saline groundwater in terms of the change yield with salinity levels, although the tolerance levels are crop-specific. Based on availability of saline groundwater, coarse textured soil, deep water table and moderate rainfall, this study also revealed that twenty-two percent or seven million hectares of the Murray hydrogeological basin in the southern Murray-Darling Basin may be suitable for the saline groundwater irrigation. However, it is also noted that the use of saline groundwater is only feasible for saline-tolerant crops under proper drainage management and by observing suitable precautionary measures. Therefore, the use of saline groundwater in irrigation requires careful attention to monitor the build up of salt in the root zone.  相似文献   
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Electroosmotic flow dynamics during a field-amplified sample stacking experiment have been studied experimentally using the periodic photobleaching of a dilute, neutral fluorophore added to the separation buffer. The effects of hydrodynamically injecting different sample plug lengths containing a mixture of arsenic compounds dissolved in 0.125 mM (120, 240, and 600 s) and 41.7 microM (27, 45, and 74 s) phosphate buffer with a separation buffer concentration of 12.5 mM phosphate buffer were examined. Changes in electroosmotic flow during sample stacking and separation were monitored at a rate of 1 Hz. The observed effects of increasing the sample plug length on electroosmotic flow and electrophoretic current agreed qualitatively with predictions by theoretical models presented in the literature. Electroosmotic flow changes on the order of 100% (1.6-3.3 mm/s) were observed. Broadening of the flow monitoring peaks has been used to examine parabolic flow due to the discontinuous buffer systems used for sample stacking.  相似文献   
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