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71.
Online communities can be an attractive source of ideas for product and process innovations. However, innovative user‐contributed ideas may be few. From a perspective of harnessing “big data” for inbound open innovation, the detection of good ideas in online communities is a problem of detecting rare events. Recent advances in text analytics and machine learning have made it possible to screen vast amounts of online information and automatically detect user‐contributed ideas. However, it is still uncertain whether the ideas identified by such systems will also be regarded as sufficiently novel, feasible and valuable by firms who might decide to develop them further. A validation study is reported in which 200 posts from an online home brewing community were extracted by an automatic idea detection system. Two professionals from a brewing company evaluated the posts in terms of idea content, idea novelty, idea feasibility and idea value. The results suggest that the automatic idea detection system is sufficiently valid to be deployed for the harvesting and initial screening of ideas, and that the profile of the identified ideas (in terms of novelty, feasibility and value) follows the same pattern identified in studies of user ideation in general.  相似文献   
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The immunomodulatory and regenerative properties of mesenchymal stromal cells (MSCs) make MSC therapy a promising therapeutic strategy in kidney disease. A targeted MSC administration via the renal artery offers an efficient delivery method with limited spillover to other organs. Although local administration alleviates safety issues with MSCs in systemic circulation, it introduces new safety concerns in the kidneys. In a porcine model, we employed intra-renal arterial infusion of ten million allogenic adipose tissue-derived MSCs. In order to trigger any potential adverse events, a higher dose (hundred million MSCs) was also included. The kidney function was studied by magnetic resonance imaging after the MSC infusion and again at two weeks post-treatment. The kidneys were assessed by single kidney glomerular filtration rate (skGFR) measurements, histology and inflammation, and fibrosis-related gene expression. None of the measured parameters were affected immediately after the administration of ten million MSCs, but the administration of one hundred million MSCs induced severe adverse events. Renal perfusion was reduced immediately after MSC administration which coincided with the presence of microthrombi in the glomeruli and signs of an instant blood-mediated inflammatory reaction. At two weeks post-treatment, the kidneys that were treated with one hundred million MSCs showed reduced skGFR, signs of tissue inflammation, and glomerular and tubular damage. In conclusions, the intra-renal administration of ten million MSCs is well-tolerated by the porcine kidney. However, higher concentrations (one hundred million MSCs) caused severe kidney damage, implying that very high doses of intra-renally administered MSCs should be undertaken with caution.  相似文献   
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Polyurethane polyols (PUPOs) and melamine polyols (MEPOs), invented by AkzoNobel Coatings, offer valuable alternatives to the commonly used polyester and acrylic polyols and new formulating tools for the development of novel coatings. The resin chemistry is based on the predominantly selective reactivity of α,β- and α,γ-diols with commonly used polyisocyanate and melamine formaldehyde crosslinkers. The resulting low molecular weight, hydroxyl functional resins are suitable for use in low VOC coatings. By choosing the appropriate crosslinker, diol, and modifier, the chemical structures of these resins can be altered to obtain the desired properties of the coatings. Synthesis methods for novel PUPOs and MEPOs and properties of one component and two component coatings containing them are described.  相似文献   
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The Symmetric Table Addition Method for Accurate Function Approximation   总被引:2,自引:0,他引:2  
This paper presents a high-speed method for computing elementary functions using parallel table lookups and multi-operand addition. Increasing the number of tables and inputs to the multi-operand adder significantly reduces the amount of memory required. Symmetry and leading zeros in the table coefficients are used to reduce the amount of memory even further. This method has a closed-form solution for the table entries and can be applied to any differentiable function. For 24-bit operands, it requires two to three orders of magnitude less memory than conventional table lookups.  相似文献   
76.
Locally produced proinflammatory cytokines are likely to play a pathophysiological role in autoimmune thyroid disease. An important feature of the thyroid, not previously considered in cytokine actions, is the barrier created by the follicular epithelium, which secludes two lumenal autoantigens [thyroglobulin (Tg) and thyroperoxidase] from the extrafollicular space. We examined the influence of recombinant cytokines on the barrier function of human thyrocytes cultured as a tight and polarized monolayer in bicameral chambers. Whereas interleukin (IL)-6 (100 U/mL), interferon-gamma (100 U/mL), tumor necrosis factor-alpha (10 ng/mL), and transforming growth factor-beta1 (10 ng/mL) had no effects, exposure to IL-1alpha for 24-48 h reduced the transepithelial resistance from >1000 to <50 omega x cm2 and increased the paracellular flux of [3H]inulin and exogenous 125I-Tg. This response to IL-1alpha, which was dose dependent (1-1000 U/mL) and reversible, was accompanied by dramatic morphological changes of the epithelial junction complex, including aberrant localization of the tight junction protein zonula occludens-1. At the same time, IL-1alpha decreased the apical secretion of endogenous Tg and stimulated the basolateral release of a novel high-molecular-mass protein. We conclude that IL-1alpha reduces the thyroid epithelial barrier without signs of general cytotoxicity. The observation suggests a mechanism by which IL-1alpha may promote the exposure of hidden autoantigens to the immune system in thyroid autoimmunity.  相似文献   
77.
Most limitations in mechanisms geared at achieving quality-of-service (QoS) in wireless ad hoc networking can be traced to solutions based on mapping wireless networks to a wireline paradigm of nodes and links. We contend that this paradigm is not appropriate since links are not physical entities and do not accurately represent the radio frequency (RF) media. Using the link abstraction makes arbitration of the use of the RF media cumbersome leaving only overprovisioning techniques to deliver QoS. In this paper, we argue that an appropriate paradigm should match the physics of the network. The critical resource is electromagnetic spectrum in a space; in turn, this results in a complex paradigm since the part of the spectrum-space that each node wants to use is unique to that node and its destination and will overlap with parts that other nodes may want to use creating interdependences among nodes. This paper describes protocol approaches for access and routing that seek solutions within this wireless paradigm. Access is arbitrated using synchronous signaling and topology is resolved through the dissemination of node states. This approach provides an intuitive framework that provides mechanisms that can be exploited to arbitrate RF media use and implement traffic engineering techniques to deliver QoS. Our proposed approach provides a novel way of tracking the state of the network that can serve as a unified state dissemination mechanism to simultaneously support routing, multicasting, and most QoS heuristics.  相似文献   
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Abstract

A systematic method of representing an explosive, based on its composition, is presented. This method is used to display performance data for existing explosives, and suggests an alternate definition for oxygen balance and determines compositions that might produce high-performance explosives. A new method for predicting the detonation velocity of a proposed explosive is also presented. This is a simple method that also yields insight into which factors are important in predicting performance.  相似文献   
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