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1.
The cell count of milk in relation to milk yield   总被引:4,自引:0,他引:4  
Quarter-milk cell counts and milk yields from 1000 cows in the province of Noord-Brabant were obtained over a 12-month period. The data from 933 animals, mainly heifers, were used to examine statistically the relationship between cell counts, as a criterion for sub-clinical forms of mastitis, and milk yield. Losses in milk were assessed by quarter, by pairs of quarters and by cow. The conclusions were that the losses in milk due to sub-clinical forms of mastitis, as indicated by cell count, can be substantial. The existence of a compensating increase in milk yield from a healthy gland, in response to the loss of milk from a neighbouring quarter with raised cell count, could not be demonstrated.  相似文献   
2.
The ability of three mixed linear models to rank sires correctly for dichotomous and ordered tetrachotomous traits was studied using simulated half-sib progeny data. The models differed in the assumptions made regarding homogeneity of residual variance. Ranking ability was assessed by estimating the realized response to truncation selection (20% of the candidates selected) upon sire evaluations in populations consisting of 50 such sires. Results suggested that weighting for unequal residual variances, in spite of reducing apparent prediction error variance, impairs the ability of best linear unbiased prediction to identify superior sires. This is consistent with theoretical arguments stemming from threshold models.  相似文献   
3.
Malt fermentability is a difficult and time consuming trait to measure. The Rapid Visco Analyser (RVA) was assessed as an alternative rapid method to indicate potential fermentability. This study evaluated changes in rheological profiles under different operational conditions and compared these changes with reference to malt fermentability from a limited number of samples. Viscosity measurements of samples were also made using different RVA (models 3D+ and 4) analysis conditions including a brewhouse time–temperature profile, heating/cooling rate, particle size and enzyme activity. Rheological measurements using the RVA‐3D + gave similar results compared with the RVA‐4, indicating adequate sensitivity of the RVA 3D+ for discriminatory purposes. Use of a time–temperature profile of a commercial brewery mashing process was unsuitable. When malt enzymes were inactivated with silver nitrate, differences in viscosities were observed. However, this eliminated the ability to discriminate on fermentability. Increasing or decreasing the heating rate influenced the time available for enzyme action, which affected the degree of discrimination. This also provided some insight into physical and biochemical processes affected by differences in particle size. RVA has the potential to be used as a tool to discriminate between poor and good fermentability barley malts. RVA conditions when using the ‘Kilned Malt’ method with an appropriate mashing malt–water ratio provided a fast and reliable indication of malt performance prior to conducting lengthy fermentability tests. Copyright © 2014 The Institute of Brewing & Distilling  相似文献   
4.
This paper presents a chronological overview of the developments in interpolation theory, from the earliest times to the present date. It brings out the connections between the results obtained in different ages, thereby putting the techniques currently used in signal and image processing into historical perspective. A summary of the insights and recommendations that follow from relatively recent theoretical as well as experimental studies concludes the presentation  相似文献   
5.
6.
Quantitative analysis of dynamic processes in living cells by means of fluorescence microscopy imaging requires tracking of hundreds of bright spots in noisy image sequences. Deterministic approaches, which use object detection prior to tracking, perform poorly in the case of noisy image data. We propose an improved, completely automatic tracker, built within a Bayesian probabilistic framework. It better exploits spatiotemporal information and prior knowledge than common approaches, yielding more robust tracking also in cases of photobleaching and object interaction. The tracking method was evaluated using simulated but realistic image sequences, for which ground truth was available. The results of these experiments show that the method is more accurate and robust than popular tracking methods. In addition, validation experiments were conducted with real fluorescence microscopy image data acquired for microtubule growth analysis. These demonstrate that the method yields results that are in good agreement with manual tracking performed by expert cell biologists. Our findings suggest that the method may replace laborious manual procedures.  相似文献   
7.
Malt has a complex microbial population, which changes as the malting process commences. Little is known about the proliferation of lactic acid bacteria (LAB) in each of the malting phases. In this study, we determined the number of LAB present in the different phases of malting with Clipper and Prisma barley cultivars. The strains were identified to species level by using numerical analysis of total soluble cell protein patterns, RAPD-PCR banding patterns and 16S rRNA sequencing. The number of viable LAB in the barley before steep was higher in Prisma than Clipper (7.6 x 10(4) and 1.2 x 10(3) cfu/g, respectively). Despite this, the number of viable cells recorded in the first steep water was slightly higher for Clipper (9.0 x 10(5) cfu/g) than Prisma (5.5 x 10(5) cfu/g). More or less, the same cell numbers were recorded for the two barley cultivars after the first and second dry stands. Both cultivars displayed more or less the same cell numbers (3.7 x 10(7) for Clipper and 3.2 x 10(7) cfu/g for Prisma) after the third day of germination. However, a higher number of LAB were detected in the kilned Prisma malt (6.9 x 10(4) cfu/g) than the Clipper malt (1.5 x 10(4) cfu/g). Leuconostoc argentinum, Le. lactis and Weissella confusa were the most predominant in both cultivars. A few strains were identified as W. paramesenteroides (four strains), Lactobacillus casei (five strains), Lactococcus lactis (five strains) and Lb. rhamnosus (two strains). Lb. casei and Lb. rhamnosus were not isolated from the Prisma cultivar, while W. paramesenteroides and Lc. lactis were absent in the Clipper cultivar. Kilned malt of the Clipper cultivar contained predominantly Le. argentinum, whereas the Prisma cultivar contained mainly Lc. lactis. To our knowledge. this is the first report of LAB in Clipper and Prisma barley and the various malting phases. The influence of the various groups of lactic acid bacteria on the fermenting ability of brewers' yeast is currently being determined.  相似文献   
8.
Image Registration for Digital Subtraction Angiography   总被引:5,自引:0,他引:5  
In clinical practice, Digital Subtraction Angiography (DSA) is a powerful technique for the visualization of blood vessels in the human body. The diagnostic relevance of the images is often reduced by artifacts which arise from the misalignment of successive images in the sequence, due to patient motion. In order to improve the quality of the subtraction images, several registration techniques have been proposed. However, because of the required computation times, it has never led to algorithms that are fast enough so as to be acceptable for integration in clinical applications. In this paper, a new approach to the registration of digital angiographic images is proposed. It involves an edge-based selection of control points for which the displacement is computed by means of template matching, and from which the complete displacement vector field is constructed by means of interpolation. The final warping of the images according to the calculated displacement vector field is performed real-time by graphics hardware. Experimental results with several clinical data sets show that the proposed algorithm is both effective and very fast.  相似文献   
9.
Serum-deprived mouse osteoblastic (MC3T3E1) cells were subjected to a vibrational force modeled by NASA to simulate a space shuttle launch (7.83 G rms). The mRNA levels for eight genes were investigated to determine the effect of vibrational force on mRNA expression. The mRNA levels of two growth-related protooncogenes, c-fos and c-myc, were up-regulated significantly within 30 min after vibration, whereas those of osteocalcin as well as transforming growth factor-beta1 were decreased significantly within 3 h after vibration. No changes were detected in the levels of beta-actin, histone H4, or cytoplasmic phospholipase A2 after vibration. No basal levels of cyclooxygenase-2 expression were detected. In addition, the extracellular concentrations of prostaglandin E2 (PGE2), a potent autocrine/paracrine growth factor in bone, were not significantly altered after vibration most likely due to the serum deprivation state of the osteoblasts. In comparison with the gravitational launch profile, vibrational-induced changes in gene expression were greater both in magnitude and number of genes activated. Taken together, these data suggest that the changes in mRNA expression are due to a direct mechanical effect of the vibrational force on the osteoblast cells and not to changes in the local PGE2 concentrations. The finding that launch forces induce gene expression is of utmost importance since many of the biological experiments do not dampen vibrational loads on experimental samples. This lack of dampening of vibrational forces may partially explain why 1-G onboard controls sometimes do not reflect 1-G ground controls. These data may also suggest that scientists use extra ground controls that are exposed to launch forces, have these forces dampened on launched samples, or use facilities such as Biorack that provide an onboard 1-G centrufuge in order to control for space shuttle launch forces.  相似文献   
10.
A note on cubic convolution interpolation   总被引:6,自引:0,他引:6  
We establish a link between classical osculatory interpolation and modern convolution-based interpolation and use it to show that two well-known cubic convolution schemes are formally equivalent to two osculatory interpolation schemes proposed in the actuarial literature about a century ago. We also discuss computational differences and give examples of other cubic interpolation schemes not previously studied in signal and image processing.  相似文献   
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