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31.
Previous work has shown that the uniformity recognition of nonwoven can be considered as a special case of pattern recognition. In this paper, a generalized frame for uniformity recognition based on computer vision and pattern recognition is introduced briefly. To validate the proposed generalized frame, a case study id carried out in experiment. In the experiment section, the uniformity recognition of nonwovens will be solved by unifying wavelet texture analysis, generalized Gaussian density (GGD) model and learning vector quantization (LVQ) neural network. 625 nonwoven images of 5 different uniformity grades, 125 of each grade, are decomposed at four levels with five different wavelet bases of Symlets family. And wavelet coefficients in each subband are independently modeled by the GGD model, while the scale and shape parameters of GGD model are extracted using maximum likelihood (ML) estimator as features to train and test LVQ neural network. For comparison, two energy-based features are also extracted from wavelet coefficients directly and jointly used as textural features. Experimental results coming from 625 nonwoven samples indicate the GGD parameters are more expressive and powerful in characterizing textures than the energy-based ones, especially when the number of decomposition levels is 4.  相似文献   
32.
随着新形势的发展,在土地方面也出现了一些新问题,新情况,作者就本地的土地流转做法,推荐一下,以供参考。  相似文献   
33.
Conventional potato breeding refers to development of new cultivars from sexual crosses followed by clonal propagation and selection. Nearly all new varieties of potato still emerge from this process free from modern technologies of gene insertion. Conventional breeding remains the most important force for introduction of new phenotypes underlain by new genes. However, these come from already selected potato breeding lines or named varieties or from wild potatoes or more distant solanaceous relatives that are amenable to somatic hybridization. Potato breeders are constantly searching for new germplasm, in part because the potato as a crop still remains highly vulnerable to biotic and abiotic stresses. In addition, the widening of the genetic base is seen as a means of increasing heterozygosity. Despite a highly conscious import of genetic variability, commercial varieties often emerge from a relatively restricted genetic pool. This is due to the long list of traits that must fall within narrow boundaries of performance. The potato must be able to navigate the conditions of modern agriculture, withstand unusual weather events, and arrive at harvest with skin and flesh appealing to the market for which it is intended. A storage period must also be endured during which appearance and suitability for processing or the consumer’s kitchen must be maintained. A lapse in any of these phases usually signals that a new variety will exit commercial use as fast as it entered. The inconvenient accompaniment of introducing exotic genetic variation is that the breeding products are often outside of the targeted market niche. It is not surprising that many new varieties stem from crosses from older named varieties. Efforts to diversify are in conflict with conformism leading to relatively high co-ancestry coefficients between advanced breeding lines. Conventional breeding has advanced through the last hundred years the appearance, sugar status, Verticillium resistance, and yield of larger sized tubers in statistically robust ways. Potato arrived from the new world and very quickly became the secret solution to famine for the poor by virtue of its productivity and nutrient content. Meanwhile, in modern times, challenges to the consumption of potato come from a sedentary and carbohydrate over-satiated society. The genetic repository of potato germplasm is so rich that a new era of potato varieties beneficial to health may be at hand. Conventional breeding will certainly be a major part of this.  相似文献   
34.
The status of the Potato virus Y (PVY) in Swiss seed potato production was investigated in the years 2003 and 2008 by analysing 385 leaf samples of field-grown, suspicious potato plants collected in four representative seed control fields. Serological investigations by ELISA showed that in c. 84% of the PVY-positive samples in both years, viruses belonging to the PVYN group were found. All 124 serologically positive PVY samples collected in 2003 and a selection of 81 isolates of 2008 were further typified by molecular tests and by biological assays on tobacco and potato plants. These tests largely confirmed the predominance of the PVYN group and, within this group, the prevalence of recombinant PVYNTN, with 81.4% and 70.4% in 2003 and 2008, respectively. The percentage of PVYN-Wilga (PVYN-Wi) increased from c. 6% to 17% between the two years. PVYO was detected only in 10.5% and 4.9% of all molecularly analysed samples in 2003 and 2008, respectively. The persistent predominance of recombinant PVYNTN in Swiss seed potatoes indicates that this strain group is now widespread, representing a considerable threat to Swiss seed potato production.  相似文献   
35.
The biofuel boom is placing enormous demands on existing cropping systems, with the most crucial consequences in the agri-food sector. The biofuel industry is responding by initiating private governance and certification. The Roundtable on Sustainable Palm Oil (RSPO) and the Cramer Commission, among others, have formulated criteria on “sustainable” biofuel production and processing. This article explores the legitimacy of private governance and certification by the biofuel industry, highlighting opportunities and challenges. It argues that the concept of output based legitimacy is problematic in the case of biofuel as long as no consensus or commonly agreed “best” solution has been established on what sustainable biofuel production is. Furthermore, it shows that the private governance initiatives analyzed fail to adequately include actors from developing countries. Finally, the article argues that we need mechanisms for control and accountability in order to guarantee that the political output of biofuel certification serves the common welfare.  相似文献   
36.
Scholars today are divided on the motivation behind what is often called Jefferson’s “moral agrarianism”. On the one hand, some scholars take Jefferson at his word when he mentions that agrarianism is a moral vision. For these individuals, Jefferson’s agrarianism is a moral vision and an indispensible part of the good life. On the other hand, other scholars maintain that Jefferson’s moral agrarianism is merely a bit of propaganda that insidiously sheaths a political or economic ideal. For them, Jefferson is through and throughout a politician, and expressions of agrarianism as a moral ideal amount to mere cant. In this paper, I examine arguments for and against Jefferson’s moral agrarianism. I defend the position that Jefferson was an aboveboard moral agrarianist and that the ideal of agrarianism was not just one that was suited for Americans, given their surfeit of land and want of laborers, but an ideal that also applied universally. I end with thoughts on Jefferson’s recognition of the rise of manufacturing in American cities throughout his life.  相似文献   
37.
This study was carried out to optimize dyeing conditions of unripe Citrus Unshiu extract on silk fabric and to evaluate antimicrobial activity of the dyed fabric for its potential use as a functional natural dye. Unripe fruits of Citrus Unshiu in Jeju Island, Korea, extracted in 80 % Ethanol solution to final solid dye powder were dyed on silk fabric under a variety of conditions such as dye bath concentrations, temperature, and dyeing duration together with mordanting. Dyeing fastness properties to washing, rubbing, perspiration, and light were tested and the antimicrobial activities of the dyed fabric against Staphylococcus aureus and Klebsiella pneumoniae were investigated quantitatively. As results, the fabric showed the maximum dye uptake (K/S) under the conditions of 80 °C for temperature, 30 min for duration, and 600 % (o.w.f.) for dye concentration. Both pre- and post-mordanting seemed not to be effective on increasing K/S values of the dyed silk fabrics under the optimum dyeing conditions. Fastness ratings to washing, rubbing, and perspiration were all very good (4–5 grades) for both 300 and 600 % dyed silk fabrics. Excellent antimicrobial activities over 99 % reduction rate against two both bacteria were exhibited for all of dyed fabrics undergone more than 300 % of dye concentration. From these results, it was concluded that the dye concentration of 300 % of unripe Citrus Unshiu could be employed to produce antimicrobial silk fabric. Furthermore, to get more saturated shades on the fabric by the citrus, higher dye concentration such as 600 % was available as well.  相似文献   
38.
39.
介绍了江苏省通州市粮食生产和需求情况,分析了影响粮食生产的主要问题,提出发展粮食生产的对策。  相似文献   
40.
Darkness suppresses ascospore release in Venturia inaequalis, but the impact of light levels during the extended twilight and dusk that typify Nordic spring conditions is poorly understood. Volumetric spore traps were operated at two different locations in Norway over several years. During the season of asocspore release (approximately 1 April to 30 June), on 25 occasions when rain started during night (after 23:00 h and before 04:00 h) and leaves remained wet until at least midnight the following day, the cumulative percentage of spores trapped at sunrise did not exceed 1%, irrespective of temperature. Three hours after sunrise, cumulative ascospore release reached 0.8%, 3.0%, and 8.1% at temperatures of 0 to 5°C, 5 to 10°C, and >10°C, respectively, and 50% release occurred at 11, 9, and 8 h after sunrise. Additional field and laboratory studies indicated that the protracted dawn and dusk of Nordic latitudes, either alone or in combination with low temperatures, does not substantially alter previously reported patterns of ascospore release.  相似文献   
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