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The performance and architecture of a high dynamic range camera (HDRC) chip and the conceptional advantages for its adaptation to image processing systems in traffic environments are discussed. The HDRC chip was developed with 64×64 pixels using a standard digital 1.2-μm CMOS technology. It is shown that the implementation proves the functionality and indicates the system performance of a highly dynamic range camera is feasible  相似文献   
3.
In this paper, a blind digital watermarking scheme for Portable Document Format (PDF) documents is proposed. The proposed method is based on a variant Quantization Index Modulation (QIM) method called Spread Transform Dither Modulation (STDM). Each bit of the secret message is embedded into a group of characters, more specifically in their x-coordinate values. The method exhibits experiments of two opposite objectives: transparency and robustness, and is motivated to present an acceptable distortion value that shows sufficient robustness under high density noises attacks while preserving sufficient transparency.  相似文献   
4.
We compare two source formulations for the electrocardiographic forward problem in consideration of their implications for regularizing the ill-posed inverse problem. The established epicardial potential source model is compared with a bidomain-theory-based transmembrane potential source formulation. The epicardial source approach is extended to the whole heart surface including the endocardial surfaces. We introduce the concept of the numerical null and signal space to draw attention to the problems associated with the nonuniqueness of the inverse solution and show that reconstruction of null-space components is an important issue for physiologically meaningful inverse solutions. Both formulations were tested with simulated data generated with an anisotropic heart model and with clinically measured data of two patients. A linear and a recently proposed quasi-linear inverse algorithm were applied for reconstructions of the epicardial and transmembrane potential, respectively. A direct comparison of both formulations was performed in terms of computed activation times. We found the transmembrane potential-based formulation is a more promising source formulation as stronger regularization by incorporation of biophysical a priori information is permitted.  相似文献   
5.
Different 13C NMR methods of determining triad distributions in two poly(ethylene-co-1-hexene) copolymers are examined using high signal-to-noise ratio 13C NMR spectra of the copolymers dissolved in deuterated 1,2,4-trichlorobenzene at 398 K. This examination includes a comparison of three integration techniques. The experimental impact of decoupler sidebands and significantly nonequal 13C NOE values are examined. A least-squares regression analysis technique for solving for triad mole fractions is tested and appears to be more reliable than two published algebraic expressions (and other expressions examined in the work reported here). The resultant triad mole fractions are compared to sequence distribution parameters expected by Bernoullian and first-order Markovian statistical models. On the basis of 13C NMR-determined average reactivity ratios, the copolymer designated sample B (5.3 mol % 1-hexene) appears to be a Bernoullian copolymer resulting from a single-site catalytic system. The copolymer designated sample S (3.6 mol % 1-hexene overall) is better described as a mixture of polyethylene and a Bernoullian copolymer with 6.4 mol % 1-hexene content, and thus appears to result from a multisite catalytic system.  相似文献   
6.
A laser scanning microscope has been developed and employed to make high precision measurements of cells from clinical cervical samples. These specimens have been stained with the DNA specific fluorochrome mithramycin and the fluorescent images analyzed to give information on nuclear size, DNA content and nuclear shape. This information has been used to develop low resolution parameters as measured with flow cytometers, thus permitting some comparisons between high resolution and low resolution features as measured from the same cells. The results indicate that both low resolution flow slit scan and high resolution pattern recognition techniques yield the same average cellular information. However, low resolution methods are insensitive to shape and the influence of shape on the broadening of low resolution features is now under investigation.  相似文献   
7.
Recent advances in understanding prejudice and intergroup behavior have made clear that emotions help explain people's reactions to social groups and their members. Intergroup emotions theory (D. M. Mackie, T. Devos, & E. R. Smith, 2000; E. R. Smith, 1993) holds that intergroup emotions are experienced by individuals when they identify with a social group, making the group part of the psychological self. What differentiates such group-level emotions from emotions that occur purely at the individual level? The authors argue that 4 key criteria define group-level emotions: Group emotions are distinct from the same person's individual-level emotions, depend on the person's degree of group identification, are socially shared within a group, and contribute to regulating intragroup and intergroup attitudes and behavior. Evidence from 2 studies supports all 4 of these predictions and thus points to the meaningfulness, coherence, and functionality of group-level emotions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
8.
The enthalpy of dissolution of two food powders, maltodextrin and skim milk, was studied by means of isothermal solution calorimetry. The effects of the moisture content and the physical state of the samples were investigated. A reduced exothermic response was found as the moisture content of the samples increased. It was shown that this effect is reversible upon re-drying of the solid, unless crystallization occurs. In the skim milk powder, crystallization of lactose occurred, leading to a less exothermic response. In addition, the dissolution kinetics of single particles was followed in situ with real time video acquisition and a novel image analysis technique. The data showed a significant effect of the physical state of the powder on the dissolution kinetics. Fully amorphous skim milk powder dissolved significantly faster than the recrystallized counterpart. A clear relation was observed between the physical state of the powders, their thermodynamic response and the dissolution kinetics.  相似文献   
9.
Most psychological theories and research on shame focus on the ugly aspects and negative consequences of this emotion. Theories on moral emotions, however, assume that shame acts as a commitment device motivating prosocial behavior. To solve this apparent paradox, the authors studied the effects of shame on prosocial behavior. Shame was hypothesized to motivate prosocial behavior when it was relevant for the decision at hand (endogenous). In contrast, shame that was not relevant for the decision at hand (exogenous) was hypothesized to have no such effects. Four experiments with three different shame inductions and two different measures of prosocial behavior confirmed that endogenous shame motivated prosocial behavior for proselfs but that exogenous shame did not. Shame is shown to have a clear interpersonal function in the sense that it acts as a commitment device. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
In preparing this Position Statement, all relevant scientific literature was identified and reviewed critically by acknowledged experts using agreed criteria. Well-conducted clinical and experimental studies were given precedence over anecdotal case reports and abstracts were not usually considered. A draft Position Statement was then produced and subjected to detailed peer review by an international group of clinical toxicologists chosen by the American Academy of Clinical Toxicology and the European Association of Poisons Centres and Clinical Toxicologists. The Position Statement went through multiple drafts before being approved by the boards of the two societies and being endorsed by other societies. The Position Statement includes a summary statement for ease of use and is supported by detailed documentation which describes the scientific evidence on which the Statement is based. Single-dose activated charcoal should not be administered routinely in the management of poisoned patients. Based on volunteer studies, the effectiveness of activated charcoal decreases with time; the greatest benefit is within 1 hour of ingestion. The administration of activated charcoal may be considered if a patient has ingested a potentially toxic amount of a poison (which is known to be adsorbed to charcoal) up to 1 hour previously; there are insufficient data to support or exclude its use after 1 hour of ingestion. There is no evidence that the administration of activated charcoal improves clinical outcome. Unless a patient has an intact or protected airway, the administration of charcoal is contraindicated.  相似文献   
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