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161.
This study investigates the potential of attenuated total reflection spectroscopy in the mid infrared (MIR) for monitoring changes in the quality of ewe’s milk as a function of lactation period and feeding systems. Twelve 5-year-old lactating Sicilo-Sarde ewes (third lambing) were kept in environmentally controlled sheepfolds and were divided into two homogenous weight matched groups (n = 6). Ewes were fed ad libitum with two iso-energetic diets (20% barley, 3% vitamin and mineral premix, and 77% soybean meal or scotch bean). Physico–chemical analyses and MIR (3000–900 cm−1) were performed on milk samples after 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10 weeks of lactation period. The inclusion of scotch bean in the diet resulted in a significant decrease (P ? 0.05) of fat content (7.85 g 100 g−1 vs. 6.75 g 100 g−1) and a significant increase (P ? 0.05) of lactose level (3.49 g 100 g−1 vs. 3.61 g 100 g−1). The principal component analysis (PCA) applied to the 1700–1500 cm−1 spectral region showed only some discrimination between milk samples according to diet compositions. The best results were obtained in the 3000–2800 cm−1 and 1500–900 cm−1 spectral regions since a good discrimination between milk from ewes fed soybean meal from those fed scotch bean meal was observed. It can be concluded that these spectral regions could be considered as fingerprint, regions allowing a good identification of milk according to diet composition. However, the MIR failed to discriminate milk samples according to the lactation period for the two feeding systems.  相似文献   
162.
The objective of this preliminary study was to evaluate the usefulness of front face fluorescence spectroscopy to predict some chemical parameters [pH, fat, dry matter (DM), fat in DM, total nitrogen (TN) and water soluble nitrogen (WSN)] and cheese meltability of semi-hard and hard cheeses. Dynamic testing rheology was used to determine the melting point of cheeses corresponding to the temperature at which loss tangent (tan δ) = 1. Tryptophan and vitamin A fluorescence spectra were, also, recorded on cheese samples at 20 °C. The partial least squares (PLS) regression with the leave one-out cross-validation technique was used to build up calibration models. Excellent predictions were obtained from the tryptophan and vitamin A models for fat (R 2 = 0.99 and 0.97, respectively), DM (R 2 = 0.94 and 0.96, respectively), fat in DM (R 2 = 0.92 and 0.99, respectively), TN (R 2 = 0.91 and 0.91, respectively). Excellent predictions were also obtained for WSN (R 2 = 0.96) and melting point (R 2 = 0.97) from vitamin A spectra, while only good predictions for these two parameters (R 2 = 0.90 and R 2 = 0.87, respectively) were obtained from tryptophan spectra. The results for pH were good (R 2 = 0.82) and approximate (R 2 = 0.76) with tryptophan and vitamin A, respectively.  相似文献   
163.
The purpose of this paper is to view recent developments in non-von Neumann and Morgenstern utility functions (vNM) via a stationary statistical-economic model. Such a model is suggested in the literature for evaluating robot precision, assuming that repeatability follows a Rayleigh distribution. Various vNM and non-vNM utility forms are discussed and illustrated for the robot evaluation and selection problem. The approach suggested here may be applicable for companies operating under profit centers where market systematic risk data are not available and decisions are based on the decision maker's (DM) attitude toward risk. Although the numerical illustrations demonstrate a consistency among the expected profit measure for most utility forms that were investigated, the analysis provides an extended framework for dealing with risky production problems. Furthermore, it illustrates the sensitivity of robot operational decisions such as speed and of both the output rate per time unit and the product quality to the DM's attitude toward risk. It allows the DM to analyze and explain decisions as affected by the selection of the utility form, as well as the technological and economic parameters and measures describing the problem, particularly the technical risk involved in the determination of a robot operational problem.  相似文献   
164.
In this paper we will discuss a formulation of the maximal covering problem when the facilities can be placed anywhere on the set R2. A selection of such problems is given. In each case we shall see that the set of locations for facility placement can be reduced to a finite set. Lastly, one of the problems is then solved using an integer program formulation.  相似文献   
165.
We describe a methodology to design and optimize Three-dimensional (3D) Tree-based FPGA by introducing a break-point at particular tree level interconnect to optimize the speed, area, and power consumption. The ability of the design flow to decide a horizontal or vertical network break-point based on design specifications is a defining feature of our design methodology. The vertical partitioning is organized in such a way to balance the placement of logic blocks and switch blocks into multiple tiers while the horizontal partitioning optimizes the interconnect delay by segregating the logic blocks and programmable interconnect resources into multiple tiers to build a 3D stacked Tree-based FPGA. We finally evaluate the effect of Look-Up-Table (LUT) size, cluster size, speed, area and power consumption of the proposed 3D Tree-based FPGA using our home grown experimental flow and show that the horizontal partitioned 3D stacked Tree-based FPGA with LUT and cluster sizes equal to 4 has the best area-delay product to design and manufacture 3D Tree-based FPGA.  相似文献   
166.
Near infrared (NIR) spectroscopy was used to predict colour of European Emmental cheese samples. Colour values (L, a and b) were measured on 20 Emmental cheese samples using a Hunter-lab D25-D-2 optical head in the system according to Hunter to determine L (brightness), a (green-red component) and b (blue-yellow component). The diffuse reflectance of the investigated cheeses was also determined by a Büchi NIR Lab N-200 spectrometer using a rotating measuring cell in the range of 1000–2500 nm. The best results for L-value (squared correlation coefficient (R 2) = 0.56, root mean square error of cross-validation (RMSECV) = 0.76, ratio of prediction deviation (RPD) = 1.89 and range error ratio (RER) = 7.91), a-value (R 2 = 0.72, RMSECV = 0.15, RPD = 1.98 and RER = 7.6) and b-value (R 2 = 0.82, RMSECV = 0.52, RPD = 2.56 and RER = 9.42) were obtained when the first 12 principal components (PCs) of the principal component analysis (PCA) applied on normalised NIR spectra were used. It can be concluded that NIR spectroscopy could be used to predict b-value. The a- and L-values can also be predicted from NIR technique with approximate quantitative prediction.  相似文献   
167.
Conventional quadrotor unmanned aerial vehicles have crucial underactuation limitations. This appears in the coupling between the roll angle and movement along the y-direction, and between the pitch angle and movement along the x-direction. The quadrotor capability of hovering with either roll or pitch angle is restricted due to these limitations. In this paper, a design modification, with experimental verification, is proposed in order to increase the quadrotor degrees of freedom and improve its hovering capability. Four additional rotations for the propellers about the axes perpendicular to the arms grant overactuated system. It could be used to make a horizontal movement with zero inclination angle which is followed in this work as an example for the skills acquired by the quadrotor due to the proposed design. Choosing different tilting axes, rather than the mostly considered ones in previous work which are about the ones along the arms, enhances the advantages of this modification. The benefits are to increase the degrees of freedom and improve the hovering of the quadrotor as well. A PID controller is utilized for practical implementation of the proposed design. Simulation and experimental results show the validity of the proposed design.  相似文献   
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