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31.
Arabinoxylans and in particular arabinoxylan oligosaccharides (AXOS) from wheat are recognised for their prebiotic potential. A high-yield, non-chemical production of AXOS is therefore of interest when producing functional foods. This study investigated the enzymatic production of AXOS from wheat bran with the aim of establishing the main fraction contributing to production of AXOS. Fractions of wheat bran, outer pericarp and aleurone with two different purities were treated with the cell wall-degrading enzymes: xylanase, cellulase and β-glucanase. The yield of solubilised arabinoxylans upon treatment was greatest in the most pure aleurone fraction (164 g kg−1) and lowest in the outer pericarp fraction (15 g kg−1). The yield was mainly recovered as AXOS rather than soluble arabinoxylans and was negatively related to the arabinose/xylose ratio found in the raw material. In conclusion, wheat aleurone cell walls are the main contributor to the production of AXOS from wheat bran and this seems to depend on the A/X ratio of the raw material.  相似文献   
32.
Design innovations have become increasingly important appropriation mechanisms for firms. Since 2003, the number of applications for design rights (protecting design innovations) has tripled compared to a doubling in the numbers of both patent and trademark applications. However, despite the growing interest of firms in design innovations, knowledge of the determinants of design innovations is limited. Prior work on labour mobility within the innovation studies literature has focused primarily on the discussion of scientists as being crucial for the creation of technological innovations. The present paper expands on this discussion by drawing parallels with the relation between scientists and technological innovation and the relation between designers and design innovation. We explore whether a similar positive relationship exists between the labour mobility of designers and the generation of design innovations and which determinants influence this relation. We employ a unique Danish dataset containing information on firms, their hiring of designers, and their design innovation activity measured by design rights. Our findings show that hiring a designer does increase the likelihood of producing a design innovation. Hence, designers are a determinant of design innovations. However, in order for the firm to benefit fully from hiring a designer, prior experience in design innovation is required.  相似文献   
33.
This paper studies the synchronization problem for a network of identical discrete‐time agents with unknown uniform constant communication delay. When the agents are non‐introspective, the problem is solvable via a decentralized low‐gain‐based synchronization controller if the delay satisfies the proposed upper bound. When the agents are introspective, the synchronization problem can be solved with arbitrary bounded communication delay. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
34.
Fj?llbrant  T. 《Electronics letters》1977,13(11):334-335
A method of data reduction applicable to sampled continuous signals, for example, sampled speech signals, is described and tested by computer simulation, Nonuniform sampling obtained through skipping of samples is used. The reconstruction network is a time-variable digital filter. A minimisation procedure for coefficient derivation is described.  相似文献   
35.
This paper focuses on how the electric field from the prey of the platypus is detected with respect to the questions of threshold determination and how the platypus might localize its prey. A new behaviour in response to electrical stimuli below the thresholds previously reported is presented. The platypus shows a voluntary exploratory behaviour that results from a temporal integration of a number of consecutive stimulus pulses. A theoretical analysis is given, which includes the threshold dependence on the number of receptors and temporal integration of consecutive stimuli pulses, the close relationships between electrical field decay across the bill, electroreceptive thresholds and directionality of the platypus bill acting as an antenna. It is shown that a lobe shape, similar to that which has been measured, can be obtained by combining responses in a specific way from receptors sensing the electric field decay across the bill. Two possible methods for such combinations are discussed and analysed with respect to measurements and observed behaviour of the platypus. A number of factors are described which need to be considered when electroreceptive thresholds are to be determined. It is shown that some information about the distance to the source is theoretically available from the pattern of field decay across the platypus's bill. The paper includes a comparative analysis of radar target tracking and platypus prey localization.  相似文献   
36.
We consider almost output synchronization for directed heterogeneous time‐varying networks where agents are non‐introspective (i.e., agents have no access to their own states or outputs) in the presence of external disturbances. The nonlinear agents have a triangular structure and are globally Lipschitz continuous. The network can be time‐varying with network switches occurring at arbitrary moments. A purely decentralized time‐invariant protocol based on a low‐gain and high‐gain method is designed for each agent to achieve almost output synchronization while reducing the impact of disturbances on the output synchronization error. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
37.
We investigate the effect of k-space broadening of the interlayer pairing kernel on the critical temperature Tc and the k-dependence of the gap function in a one-dimensional version of the interlayer pair-tunneling model of high-Tc superconductivity. We consider constant as well as k-dependent intralayer pairing kernels. We find that the sensitivity to k-space broadening is larger the smaller the width of the peak of the Fermi-level gap calculated for zero broadening. This width increases with the overall magnitude of the interlayer tunneling matrix element, and decreases with the bandwidth of the single-electron intralayer excitation spectrum. The width also increases as the Fermi level is moved towards regions where the excitation spectrum flattens out. We argue that our qualitative conclusions are valid also for a two-dimensional model. This indicates that at or close to half-filling in two dimensions, when the Fermi-surface gap for zero broadening attains its peaks at (±/a, 0) and (0, ±/a) where the excitation spectrum is flat, these peaks should be fairly robust to moderate momentum broadening.  相似文献   
38.
In this paper, we study the disturbance response of open‐loop neutrally stable linear systems with saturating linear feedback controller. It is shown that the closed‐loop states remain bounded if the disturbances consists of those signals that do not have large sustained frequency components corresponding to the system's eigenvalues on the imaginary axis (continuous‐time) or on the unit circle (discrete‐time). Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   
39.
In this paper, we investigate the relationship between stability and internal stability of nonlinear systems. It is shown that under certain conditions, stability implies attractivity of the equilibrium and that local stability with finite gain implies local asymptotic stability of the origin. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
40.
The phase formation, heat of hydration and dilatation in a blended cement consisting of 50 wt.% calcium aluminate cement, 25 wt.% Portland cement and 25 wt.% calcium sulfate were studied (w/c=1). The calcium sulfate was β-hemihydrate, anhydrite and mixes of the two. Kinetic expressions describing the ettringite formation in the pastes with the pure calcium sulfates were found. Hydration reactions were suggested and the phase development was compared to the hydration heat by mass and heat balances. When the calcium sulfate was 75 and 50 wt.% β-hemihydrate, the systems behaved as a linear combination of the 100 and 0 wt.% blends. At 25 wt.%, the hydration kinetics differed from the other blends. With only β-hemihydrate, the last 50% of ettringite formation was accompanied by expansion, mainly caused by interaction of crystals growing radially on cement grains. In the paste with only anhydrite, ettringite crystals grew in solution and produced no expansion.  相似文献   
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