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1.
Abstract. This paper describes artificial neural network based pure significance tests for the unit root hypothesis against nonlinear alternatives. The theoretical properties of the tests are discussed and a Monte Carlo investigation of their small sample properties is undertaken.  相似文献   
2.
Milk-based formulas with proximate analyses similar to infant formulas were heated to determine influence of headspace, reel speed, solids content, and consistency on Fo. Concentrations with 12.5, 25, and 30% solids were heated in three can sizes. Increasing Steritort rpm from 3.4 to 10.9 for 307 × 710 cans (12.5% solids) had greatest effect; the Fo increased from 9.8 to 12.3. The same increase in rpm for a continuous retort would reduce Fo from 9.8 to 2.0 because of reduced processing time. Solids content and consistency influenced heating, but variations in consistency of a given concentration had no measurable effect on Fo. Headspace influenced heating for each concentration, but was not as critical as for more viscous products.  相似文献   
3.
A major problem in modern information systems is to locate information and to re-find information one has seen before. Systems like the World Wide Web are heavily interlinked, but do not show structures that help users to navigate the information it contains. The use of appropriate navigation metaphors can help to make the structure of modern information systems easier to understand and therefore easier to use.We propose a conceptual user interface metaphor based on the structure of a city. Cities are very complex spatial environments and people know how to get information, how to reach certain locations in a city, and how to make use of the available infrastructure, etc. Cities provide a rich set of navigational infrastructure that lends itself to creating sub-metaphors for navigational tools. A city metaphor makes this existing knowledge about a structured environment available to the user of a computerized information system.We first focus on several properties necessary for future user interfaces (or user interface metaphors) that will distinguish them from current systems, like the richness of information or the use of visualizations to show the structure of information spaces. We also describe the strengths and problems of spatial user-interface metaphors. Then we present the structure of the information city metaphor, its structuring and navigation metaphors and what we see as its main advantages and problems. We further outline a few scenarios of how an Information City might work. Finally, we compare implementing this metaphor using either a textual or a graphical virtual environment or a combination.  相似文献   
4.
Throughout this account, the growing interest in management strategy, as a subject which can be planned, as well as described, by upper-echelon managers has been indicated.

The most important concept that has been outlined is that the need for a planned management strategy arises directly from the task which management sets itself when it tries to control its environment. It is not merely a need which becomes apparent at a high level of management complexity, but is inherently part of the function of management.

The second important idea, implicit throughout this account, and made explicit in §7, is that models of the organization are baaed on axioms which must be outlined at the highest level of control in an organization—by the board of directors : thus, the board have a direct influence, as well as ultimate responsibility, in the modelling activities of managers who construct and carry out planned strategic decisions.  相似文献   
5.
A multi-state deterministic system controlled via a noisy Binary Symmetric Channel (BSC) is modelled by an equivalent Markov chain. The system performs a random walk whose mean deviation from zero is numerically equal to the expected number of steps between zero crossings, and whose entropy is equal to the average amount of transmitted control information between zero crossings. Simple expressions are found for the received control information and for the mutual information via the BSC.  相似文献   
6.
Rice flour and yellow or white corn flour were combined at 50, 60 and 70% levels with mechanically deboned turkey and extrusion processed at 104C and 121C. The texture of the extrudates was evaluated by Warner-Bratzler shear (WBS), and flour concentration had more effect on the WBS values than flour type; treatments with 70% flour had significantly greater WBS values. Corn flour treatments and low temperature extrusion resulted in greater TBA values. Proximate composition of extrudates confirmed moisture losses during extrusion and that high temperature processing had mixed results on ether-extractable compounds.  相似文献   
7.
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Abstract

This paper outlines a new approach to the synthesis of information from data. Information is defined as a detected organization of data after a process of discretization (or partitioning) and event covering. The discretization is based on a hierarchical maximum entropy scheme which iteratively minimizes the loss of information according to Shannon. The event-covering process is based on an evaluation of the deviation of the observed frequencies of an event from the expectation due to prior knowledge (defined by the null hypothesis and/or domain knowledge). The hierarchical maximum entropy discretization scheme provides a rigorous and efficient way in solving the non-uniform scaling problem in multivariate data analysis. Because our method refines the boundaries dynamically depending on the detection of information, it directs the analysis on the outcome subspace with high information content. In addition, it naturally produces a hierarchical view of information so that data can be analyzed/synthesized with respect to an outcome context. The method has been tested using simulated and real life data with very good result.  相似文献   
9.
Abstract

Problems of accurate discrimination between snow and cloud, together with the detection of the snow pack boundary, have handicapped the use of satellite data in operational snow-cover mapping systems. A technique, involving an unsupervised clustering procedure, is described which allows the removal of cloud areas using NOAA-9 Advanced Very High Resolution Radiometer (AVHRR) channel-1, channel-3 and channel-4 data in conditions of recent snow lie and a difference channel (channel-2 —channel-1 with channel-3 and channel-4) during periods of advanced snow melt. Accurate delineation of snow extent is provided by the techniques if these specified snow conditions are taken into account. A method for the identification of areas of marginal snow melt is also presented, based on comparisons with Landsat Thematic Mapper data. The classifications also enable the determination of snow areas influenced by cloud shadows and conifer forest in addition to separating areas of differing snow depth and percentage cover.  相似文献   
10.
The relationships between the composition and ultrasonic properties of Atlantic cod (Gadus morhua) fillets were examined. The lipid, protein, moisture and ash contents of cod fillets were determined by official methods. The ultrasonic velocity and attenuation coefficient of the fillets were measured using a pulse-echo technique. The ultrasonic velocity of the fillets varied between 1575 and 1595 m s?1, decreasing linearly with increasing moisture content (r2 > 0.8 for 26 samples). No systematic relationship was observed between the attenuation coefficient and moisture content. Our experiments highlight the potential of using ultrasonic velocity measurements to rapidly and nondestructively determine the moisture content of cod fillets (and possibly their protein content by deduction).  相似文献   
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