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91.
Dipl.-Math. Cornelius Köpp Prof. Dr. Hans-Jörg von Mettenheim Prof. Dr. Michael H. Breitner 《WIRTSCHAFTSINFORMATIK》2014,56(3):147-157
Today’s forecasting techniques, which are integrated into several information systems, often use ensembles that represent different scenarios. Aggregating these forecasts is a challenging task: when using the mean or median (common practice), important information is lost, especially if the underlying distribution at every step is multimodal. To avoid this, the authors present a heatmap visualization approach. It is easy to visually distinguish regions of high activity (high probability of realization) from regions of low activity. This form of visualization allows to identify splitting paths in the forecast ensemble and adds a “third alternative” to the decision space. Most forecast systems only offer “up” or “down”: the presented heatmap visualization additionally introduces “don’t know”. Looking at the heatmap, regions can be identified in which the underlying forecast model cannot predict the outcome. The authors present a software prototype with interactive visualization to support decision makers and discuss the information gained by its use. The prototype has already been presented to and discussed with researchers and practitioners. 相似文献
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93.
Neil Macfarlane Tony Swetman J. A. Cornelius 《Journal of the science of food and agriculture》1975,26(9):1293-1298
The mesocarp oil of the American oil palm is more unsaturated than that of the West African oil palm. Mesocarp oils obtained from F1 hybrids of these two oil palms exhibit an intermediate degree of unsaturation. Hybrid kernel oils are similar in composition to that of their West African oil palm parent, whereas kernel oils from the American oil palm are considerably more unsaturated and exhibit a unique fatty acid composition among seed fats of the Palmae family. 相似文献
94.
Real-time adaptive microstimulation increases reliability of electrically evoked cortical potentials
Brugger D Butovas S Bogdan M Schwarz C 《IEEE transactions on bio-medical engineering》2011,58(5):1483-1491
Cortical neuroprostheses that employ repeated electrical stimulation of cortical areas with fixed stimulus parameters, are faced with the problem of large trial-by-trial variability of evoked potentials. This variability is caused by the ongoing cortical signal processing, but it is an unwanted phenomenon if one aims at imprinting neural activity as precisely as possible. Here, we use local field potentials measured by one microelectrode, located at a distance of 200 microns from the stimulation site, to drive the electrically evoked potential toward a desired target potential by real-time adaptation of the stimulus intensity. The functional relationship between ongoing cortical activity, evoked potential, and stimulus intensity was estimated by standard machine learning techniques (support vector regression with problem-specific kernel function) from a set of stimulation trials with randomly varied stimulus intensities. The smallest deviation from the target potential was achieved for low stimulus intensities. Further, the observed precision effect proved time sensitive, since it was abolished by introducing a delay between data acquisition and stimulation. These results indicate that local field potentials contain sufficient information about ongoing local signal processing to stabilize electrically evoked potentials. We anticipate that adaptive low intensity microstimulation will play an important role in future cortical prosthetic devices that aim at restoring lost sensory functions. 相似文献
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96.
The per cent by mass of crystalline solid in a partly frozen hydrocarbon fuel cannot be determined by a filtration experiment alone because the precipitate retained by the filter entraps large amounts of the liquid phase. A technique has been developed which augments the filtration experiment with an independent determination of the amount of liquid in the precipitate and hence allows calculation of the true value of the mass percent of crystalline solid, %S. This method involves the addition to the initial fuel of a small amount of a non-crystallizing dye as a tracer and the determination of the amount of entrapped liquid in the precipitate fraction by a spectrophotometric comparison of the dye concentrations in the precipitate and filtrate. The technique has been tested at several temperatures on both a diesel and a jet fuel. %S increased with decreasing temperature below the melting point. The %S values for the jet fuel were in good agreement with results obtained in another laboratory using a filtration/g.c. analysis method. Precipitates obtained by filtration of the partly frozen fuels were found to contain 50–80% entrapped liquid. 相似文献
97.
We examined everyday problem solving in adulthood and compared it with traditional measures of cognitive abilities. In the first phase of the research, we describe the construction of an inventory to assess problem solving in situations that adults might encounter in everyday life and examine raters' judgments of effective responses to the problems. In the second phase, adults (N?=?126) between the ages of 20 and 78 were administered the inventory and tests of verbal and abstract problem-solving abilities. Results indicated modest but significant positive correlations between performance on the inventory and traditional ability tests. The examination of age differences revealed that performance on the Everyday Problem-Solving Inventory and verbal ability test increased with age, whereas performance on a traditional problem-solving test declined after middle age. In addition, education was unrelated to everyday problem solving, highly related to verbal ability, and moderately related to traditional problem solving. Results are discussed in relation to pluralistic conceptions of intelligence and theories of adult intellectual development. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
高画质电视(HDTV)至今仍是全球消费性电子市场最受瞩目的产品.当大幅提升的影像画质已吸引全球消费者的目光,业界仍面临一个挑战,必须以更低廉的价位满足消费者对于轻、薄、大屏幕HDTV产品的需求. 相似文献
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Recombinant human erythropoietin (rhEPO) and darbepoetin alfa (DPO) are protein-based drugs for the treatment of anemia in humans by stimulating erythrocyte production. However, these agents are abused in human and equine sports due to their potential to enhance performance. This paper describes the first method for differentiation and identification of rhEPO and DPO in equine plasma by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). The method comprised analyte extraction and enrichment by immunoaffinity separation with anti-rhEPO antibodies, dual digestion by trypsin and peptide-N-glycosidase F (PNGase F), and analysis by LC-MS/MS. Two unique deglycosylated tryptic peptides, (21)EAENITTGCAEHCSLNENITVPDTK (45) (T 5) from rhEPO and (77)GQALLVNSSQVNETLQLHVDK (97) (T 9) from DPO, were employed for differentiation and identification of rhEPO and DPO via LC retention times and major product ions. The limit of identification was 0.1 ng/mL for DPO and 0.2 ng/mL for rhEPO in equine plasma, and the limit of detection was 0.05 ng/mL for DPO and 0.1 ng/mL for rhEPO. Analyte carryover problem encountered was solved by adding 20% acetonitrile to the solvent of the sample digest to increase solubility of the peptides. This method was successfully applied to identification of DPO in plasma samples collected from a research horse following DPO administration and from racehorses out of competition in North America. Thus, it provides a powerful tool in the fight against blood doping with rhEPO and DPO in the horse racing industry. 相似文献