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51.
A Prüfer-coded genetic algorithm based on the decimal number of nodes is proposed and it is used to solve collaborative optimization planning of access solution of distributed generation(DG)and structure of distribution network.Using graph theory to generate theoretically feasible topology structureand the access nodes and the installed capacity of distributed generation are coded by the Prüfer number.The coding method makes the distribution network operation structure and the access solution of DG combine into the evolution problem of the same chromosomal gene.The length of the chromosome coding of this method is shorter than binary encoding.This solution takes full advantage of the Prüfer-coded to improve computational efficiency and convergence rateand makes some restrictions and improvements in some key parts of the algorithm to solve the problem illegal solution.Finallyfeasibility and superiority of the algorithm is validated by a case study. 相似文献
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Serum osteocalcin or bone Gla-protein, a biochemical marker for bone metabolism in horses: differences in serum levels with age. 总被引:1,自引:1,他引:1
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Levels of alkaline phosphatase and osteocalcin or bone Gla-protein, a new marker of bone metabolism, were analyzed in blood samples of 50 clinically normal female Standardbred horses between four months and twenty years of age. Samples were collected in the morning before exercise. Serum osteocalcin was measured by radioimmunoassay using bovine antibodies. There was a significant inverse correlation between alkaline phosphatase, osteocalcin and the age of the animals up to 48 months. The decrease in osteocalcin levels in serum was very marked during the first 30 months of life. The mean osteocalcin concentration was respectively 47.3, 35.7 and 6.7 ng/mL for animals less than one year, between 1.5 and 2.5 years of age and older than 3.5 years. Alkaline phosphatase serum activity was higher in foals less than one year of age (means = 856 U/L) than in the two older groups (meansII = 339, meansIII = 351 U/L). We believe that osteocalcin is a useful parameter for the evaluation of bone metabolism in growing animals and in adults and is probably more specific than alkaline phosphatase. 相似文献
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Ivar V gsholm Hans Olav Djupvik Finn Victor Willumsen Anne Marie Tveit Karl Tangen 《Preventive veterinary medicine》1994,19(3-4):277-290
A case-control study is reported of 57 holdings (holdings in which salmon are raised in sea-water) with infectious salmon anaemia (ISA) and 61 holdings without ISA, together with a follow-up study of the control holdings, during 1988–1990. Generally the identified risk factors implied poor biosecurity since passive transmission (proximity to other ISA holdings) and active transmission (management practices which increased exposure to foreign biological material) were found to be major risk factors. The findings indicated that ISA was spread by infected live salmon or infected biological material i.e. animal waste or discharge from normal operations and slaughter. The findings also indicated that decreased host resistance could be important, but these results could be also be explained by a misclassification bias. Moreover, the findings indicate that a prompt eradication policy and improved biosecurity would be important means of controlling ISA. 相似文献
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利用玉米优良自交系农系531和X178杂交构建的200份RIL群体,基于GBS技术获得SNP标记构建高密度的重组bin遗传连锁图谱,定位控制玉米子粒容重相关QTL。结果表明,构建的物理图谱和遗传图谱的总长度分别为2 017.03 Mb和2 568.99 cM,相邻两个bin标记之间的平均物理距离和平均遗传距离分别为0.27 Mb和0.35 cM。运用所构建的遗传连锁图谱对RIL群体获得的所有目标性状进行连锁作图,两年共定位到4个与子粒容重相关的QTL位点,分别位于chr1、chr7和chr8上;穗部性状穗长、穗粗、穗行数、行粒数和出籽率两年分别共定位到了6、5、5、1、2个QTL位点,位点分布于chr1、chr2、chr3、chr4、chr5、chr7和chr8上。 相似文献
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Six cases of ocular lymphocystis, a virus disease, are described. Lymphocystis is generally known as a benigh, unique, giant cell disease of fishes causing nodules on the skin and fins. It has been studied extensively because of the virus-host cell relationship that results in extreme size and lack of quick cellular destruction or stimulation to neoplasia. Lymphocystis cells were found behind or in one or both eyes and were also found on the cornea or adjacent skin surfaces. A retrobulbar mass produced extreme exophthalmos. Uveal (choroid and iris) masses were present in most cases. Optic nerve involvement was also seen. It is probable that the virus reached the eye by the blood with the resulting masses forming in situ rather than by direct extension from skin lesions. 相似文献