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51.
Local processing, which is a dominant type of processing in image and video applications, requires a huge computational power to be performed in real-time. However, processing locality, in space and/or in time, allows to exploit data parallelism and data reusing. Although it is possible to exploit these properties to achieve high performance image and video processing in multi-core processors, it is necessary to develop suitable models and parallel algorithms, in particular for non-shared memory architectures. This paper proposes an efficient and simple model for local image and video processing on non-shared memory multi-core architectures. This model adopts a single program multiple data approach, where data is distributed, processed and reused in an optimal way, regarding the data size, the number of cores and the local memory capacity. The model was experimentally evaluated by developing video local processing algorithms and programming the Cell Broadband Engine multi-core processor, namely for advanced video motion estimation and in-loop deblocking filtering. Furthermore, based on these experiences it is also addressed the main challenges of vectorization, and the reduction of branch mispredictions and computational load imbalances. The limits and advantages of the regular and adaptive algorithms are also discussed. Experimental results show the adequacy of the proposed model to perform local video processing, and that real-time is achieved even to process the most demanding parts of advanced video coding. Full-pixel motion estimation is performed over high resolution video (720×576 pixels) at a rate of 30 frames per second, by considering large search areas and five reference frames.  相似文献   
52.
Solid oxide fuel cells (SOFC) using a pulsed laser deposited bi-layer electrolyte have been successfully fabricated and have shown very good performance at low operating temperatures. The cell reaches power densities of 0.5 W cm−2 at 550 °C and 0.9 W cm−2 at 600 °C, with open circuit voltage (OCV) values larger than 1.04 V. The bi-layer electrolyte contains a 6–7 μm thick samarium-doped ceria (SDC) layer deposited over a ∼1 μm thick scandium-stabilized zirconia (ScSZ) layer. The electrical leaking between the anode and cathode through the SDC electrolyte, which due to the reduction of Ce4+ to Ce3+ in reducing environment when using a single layer SDC electrolyte, has been eliminated by adopting the bi-layer electrolyte concept. Both ScSZ and SDC layers in the bi-layer electrolyte prepared by the pulsed laser deposition (PLD) technique are the highly conductive cubic phases. Poor conductive (Zr, Ce)O2-based solid solutions or β-phase ScSZ were not found in the bi-layer electrolyte prepared by the PLD due to low processing temperatures of the technique. Excellent reliability and flexibility of the PLD technique makes it a very promising technique for the fabrication of thin electrolyte layer for SOFCs operating at reduced temperatures.  相似文献   
53.
Electrophysiological investigations were carried out both in patients with carpal tunnel syndrome (CTS) and in healthy individuals. The evoked potentials were examined during stimulation of sensitive branches of n. medianus and of other nerves. The most sensitive and important for diagnosis appeared to be the electrophysiological test of alteration of responsive reaction to the stimulation of the sensitive branch of n. medianus for 4 finger and the considerable difference of evoked reactions on stimulation of skin palm branch and branch of the 1-st finger of n. medianus. The diagnostic importance of these indices corresponds well to anatomical and pathophysiological characteristics of CTS.  相似文献   
54.
Resting membrane potential (RMP), K+ channel contribution to RMP and the development of excitability were investigated in the entire population of acutely dissociated embryonic (E) rat cortical cells over E11-22 using a voltage-sensitive fluorescent indicator dye and flow cytometry. During the period of intense proliferation (E11-13), two cell subpopulations with distinct estimated RMPs were recorded: one polarized at approximately -70 mV and the other relatively less-polarized at approximately -40 mV. Ca2+o was critical in sustaining the RMP of the majority of less-polarized cells, while the well-polarized cells were characterized by membrane potentials exhibiting a approximately Nernstian relationship between RMP and [K+]o. Analysis of these two subpopulations revealed that > 80% of less-polarized cells were proliferative, while > 90% of well-polarized cells were postmitotic. Throughout embryonic development, the disappearance of Ca2+o-sensitive, less-polarized cells correlated with the disappearance of the proliferating population, while the appearance of the K+o-sensitive, well-polarized population correlated with the appearance of terminally postmitotic neurons, immuno-identified as BrdU-, tetanus toxin+ cells. Differentiating neurons were estimated to contain increased K+i relative to less-polarized cells, coinciding with the developmental expression of Cs+/Ba2+-sensitive and Ca2+-dependent K+ channels. Both K+ channels contributed to the RMP of well-polarized cells, which became more negative toward the end of neurogenesis. Depolarizing effects of veratridine, first observed at E11, progressively changed from Ca2+o-dependent and tetrodotoxin-insensitive to Na+o-dependent and tetrodotoxin-sensitive response by E18. The results reveal a dynamic development of RMP, contributing K+ channels and voltage-dependent Na+ channels in the developing cortex as it transforms from proliferative to primarily differentiating tissue.  相似文献   
55.
A metal-supported SOFC with a samarium doped ceria (SDC)/scandia-stabilized zirconia (ScSZ) bilayer electrolyte was fabricated by a combination of pulsed laser deposition (PLD) and wet ceramic processes. The cell performance and aging characteristics during operation were analyzed by both AC impedance spectroscopy and current-voltage measurements in the temperature range from 400 °C to 600 °C. The power generation characteristics of this metal-supported SOFC at low temperatures should allow for rapid start-up and help to reduce the performance deterioration seen in high temperature SOFCs due material oxidation and instability. In this paper, our early research results are presented.  相似文献   
56.
Lactulose can be considered as a prebiotic, which is able to stimulate healthy intestinal microflora. In the present work, the use of this ingredient in fermented milk improved quality of skim milk fermented by Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus bulgaricus and Bifidobacterium lactis in co-culture with Streptococcus thermophilus. Compared to control fermentations without lactulose, the addition of such a prebiotic in skim milk increased the counts of all probiotics, with particular concern to B. lactis (bifidogenic effect), the acidification rate and the lactic acid acidity, and concurrently reduced the time to complete fermentation (tpH4.5) and the pH at the end of cold storage for 1 to 35 days.  相似文献   
57.
In functional dairy products, polyunsaturated fatty acids such as, conjugated linoleic acid (CLA) and α-linolenic acid (ALA) have been highlighted for their benefits related to prevention of some chronic diseases. In order to study the effect of type of milk (conventional vs. organic, characterized by a specific fatty acid composition), Bifidobacterium animalis subsp. lactis (BB12, B94, BL04 and HN019) counts, acidification activity and chemical composition (pH, lactose, lactic acid contents and fatty acids profile) were investigated before fermentation and after 24 h of products stored at 4 °C. Organic and conventional milk influenced acidification performance and bacteria counts, which was strain-dependent. Higher counts of BB12 were observed in organic milk, whereas superior counts of BL04 were found in conventional milk. Organic fermented milk showed lower levels in saturated fatty acids (FA) and higher in monounsaturated FA contents. Similarly, among bioactive FA, organic fermented milks have higher amounts of trans vaccenic acid (TVA–C18:1t), conjugated linoleic acid (CLA) and slightly higher contents of α-linoleic acid (ALA).  相似文献   
58.
Micromachines are at the forefront of materials research as they are self‐propelled, smart autonomous systems capable of acting as an intelligent matter. One of the obstacles the field faces is tracking individual micromachines carrying molecular cargo from the rest of the micromachines. Highly stable fluorescent markers based on chemically modified 2D germanene compounds are developed. Two different 2D germanene derivatives, 4‐fluorophenylgermanane (2D‐Ph‐Ge) and methylgermanane (2D‐Me‐Ge), exhibit different fluorescence under UV light irradiation (excitation at 365 nm), which allows one particular micromotor to be easily distinguished in a mixture of micromotors. This offers a paradigm shift toward a new approach of multiplex detection of self‐propelled micromachines. The utility is demonstrated on a drug delivery system, where micromachines carrying a drug are labeled with 2D‐Ph‐Ge with blue emission while bare micromachines are labeled by 2D‐Me‐Ge with red emission. This approach of functional fluorescent labeling will pave the way to multiple simultaneous functionalized micromachines identification in complex environments.  相似文献   
59.
Styrene/acrylonitrile (S/AN) and tert‐butyl methacrylate/acrylonitrile (tBMA/AN) copolymers were synthesized in a controlled manner (low polydispersity $ {{\overline M _w } / {\overline M _n }} $ with linear growth of number average molecular weight $ \overline M _n $ vs. conversion X) by nitroxide mediated polymerization (NMP) with a succinimidyl ester (NHS) terminated form of BlocBuilder unimolecular initiator (NHS‐BlocBuilder) in dioxane solution. No additional free nitroxide (SG1) was required to control the tBMA‐rich copolymerizations with NHS‐BlocBuilder, a feature previously required for methacrylate polymerizations with BlocBuilder initiators. Copolymers from S/AN mixtures (AN molar initial fractions fAN,0 = 0.13–0.86, T = 115°C) had $ {{\overline M _w } / {\overline M _n }} $ = 1.14–1.26 and linear $ \overline M _n $ versus conversion X up to X ≈ 0.6. tBMA/AN copolymers (fAN,0 = 0.10–0.81, T = 90°C) possessed slightly broader molecular weight distributions ( $ {{\overline M _w } / {\overline M _n }} $ = 1.23–1.50), particularly as the initial composition became richer in tBMA, but still exhibited linear plots of $ \overline M _n $ versus conversion X up to X ≈ 0.6. A S/AN/tBMA terpolymerization (fAN,0 = 0.50, fS,0 = 0.40) was also conducted at 90°C and revealed excellent control with $ \overline M _n $ = 13.6 kg/mol, $ {{\overline M _w } / {\overline M _n }} $ = 1.19, and linear $ \overline M _n $ versus conversion X up to X = 0.54. Incorporation of AN and tBMA in the final copolymer (molar composition FAN = 0.47, FtBMA = 0.11) was similar to the initial composition and represents initial designs to make tailored, acid functional AN copolymers by NMP for barrier materials. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013  相似文献   
60.
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