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921.
提出了一种由样品辨识、模糊推理和控制处理 3个子网模块构成的基于知识的多层神经网络 .这种网络由各子网分别构成并按照最初的模糊控制结构适当连接而建立 ,具有明确区分各组成子网功能及其知识流结构 .由于综合了模糊逻辑的推理过程及神经网络的学习能力 ,使它能够在其结构中以模糊规则的形式引入语言知识并通过网络的训练及自学习对这些知识进行加工 ,从而实现了真正意义上的自适应模糊控制器 .最后还讨论了这种 NFN网络在动态过程控制中的应用 相似文献
922.
顾成扬 《淮阴师范学院学报(自然科学版)》2002,1(3):6-9
本文给出完全图Kn和完全多部图Kn(t)存在{C3, S4}-强制分解的充分必要条件. 相似文献
923.
924.
A I den Hollander J B ten Brink Y J de Kok S van Soest L I van den Born M A van Driel D J van de Pol A M Payne S S Bhattacharya U Kellner C B Hoyng A Westerveld H G Brunner E M Bleeker-Wagemakers A F Deutman J R Heckenlively F P Cremers A A Bergen 《Nature genetics》1999,23(2):217-221
Retinitis pigmentosa (RP) comprises a clinically and genetically heterogeneous group of diseases that afflicts approximately 1.5 million people worldwide. Affected individuals suffer from a progressive degeneration of the photoreceptors, eventually resulting in severe visual impairment. To isolate candidate genes for chorioretinal diseases, we cloned cDNAs specifically or preferentially expressed in the human retina and the retinal pigment epithelium (RPE) through a novel suppression subtractive hybridization (SSH) method. One of these cDNAs (RET3C11) mapped to chromosome 1q31-q32.1, a region harbouring a gene involved in a severe form of autosomal recessive RP characterized by a typical preservation of the para-arteriolar RPE (RP12; ref. 3). The full-length cDNA encodes an extracellular protein with 19 EGF-like domains, 3 laminin A G-like domains and a C-type lectin domain. This protein is homologous to the Drosophila melanogaster protein crumbs (CRB), and denoted CRB1 (crumbs homologue 1). In ten unrelated RP patients with preserved para-arteriolar RPE, we identified a homozygous AluY insertion disrupting the ORF, five homozygous missense mutations and four compound heterozygous mutations in CRB1. The similarity to CRB suggests a role for CRB1 in cell-cell interaction and possibly in the maintenance of cell polarity in the retina. The distinct RPE abnormalities observed in RP12 patients suggest that CRB1 mutations trigger a novel mechanism of photoreceptor degeneration. 相似文献
925.
为了研究织机上的打纬和织物形成过程,本文提出了以频闪摄影测定纱线弯曲刚度的实验方法,并运用该方法对不同纱线的弯曲刚度进行了测定。 相似文献
926.
S. Steghaus-Kovâc U. Maschwitz A. B. Attygalle R. T. S. Frighetto N. Frighetto O. Vostrowsky H. J. Bestmann 《Cellular and molecular life sciences : CMLS》1992,48(7):690-694
Behavioral tests carried out with the four stereoisomers of 4-methyl-3-heptanol revealed thatLeptogenys diminuta ants respond specifically only to the (3R, 4S)-isomer. 相似文献
927.
Y. Sakagami K. Taki T. Matsuhisa S. Marumo 《Cellular and molecular life sciences : CMLS》1992,48(8):793-795
2-Deoxyecdysone was purified from the miteTyrophagus putrescentiae and monitored by a radioimmunoassay. The compound was identified by GC-MS and LC-MS. This is the first report of an endogenous ecdysteroid from a mite. 相似文献
928.
T. Horio Y. Kawabata T. Takayama S. Tahara J. Kawabata Y. Fukushi H. Nishimura J. Mizutani 《Cellular and molecular life sciences : CMLS》1992,48(4):410-414
A highly potent attractant of zoospores ofAphanomyces cochlioides, a causal fungus of the root rot disease of spinach (Spinacia oleracea), was isolated from spinach roots, and its structure was determined by spectroscopic evidence and chemical synthesis as cochliophilin A (5-hydroxy-6,7-methylenedioxyflavone,1). A chromosorb particle prepared by soaking in solution of1 showed a potent attracting activity toward the zoospores using concentrations of1 above 10–9 or 10–10 M. 相似文献
929.
D. Krüger R. Grossklaus M. Herold S. Lorenz L. Klingebiel 《Cellular and molecular life sciences : CMLS》1992,48(8):733-740
Using data obtained with a dye marker and the gavage technique, the kinetics of gastrointestinal transit of different loads of sugar substitutes (maltitol, sorbitol) and sugar (sucrose) in the rat were analysed using a linear multicompartmental model over a range from the realistic to the non-physiologic high, of carbohydrate intake levels and using only a few experimental time points. The model gave detailed insight into intestinal propulsion and gastrocecal transit time. Rate constants of transport between the compartments investigated were determined; they showed characteristics which could be related to the substance and the dosage administered. Analyses of the gastrointestinal content and calculations of the intestinal net water movement showed that the digestibility and absorption of the disaccharide sugar alcohol, maltitol, in the small gut depended inversely on the dose ingested. For all substances tested, caloric availability in the small intestine was calculated. At a physiological low level of maltitol intake, the results also indicated an insignificant calorie-saving effect in comparison to sucrose, an effect based mainly on the slow absorption rate of the maltitol cleavage product sorbitol. 相似文献
930.
S. C. Miller 《Cellular and molecular life sciences : CMLS》1992,48(7):674-678
During 21 days of indomethacin treatment, erythroid cells in the spleens of both young adult and older mice, and in the bone marrow of young adult mice, were increased significantly early, in treatment, relative to age-matched control organs, and remained high throughout treatment. During drug exposure, the numbers of myeloid cells in young adult bone marrow, but not spleen, were reduced, but in older mice these cells were elevated in both organs. Lymphoid cells in the young adult and older mouse spleens decreased and increased, respectively, during treatment, but were unchanged and decreased, respectively, in the bone marrow of young adult and older mice. Monocytemacrophage cells in the spleen were elevated but unchanged in the bone marrow of both age groups. During 14 days of indomethacin treatment of houng adult mice, the proportions of precursor cells in DNA synthesis of only the splenic erythroid lineage were increased. Thus, the major hemopoietic lineages in both the bone marrow and spleen are affected by exposure to indomethacin in a time-dependent and age-dependent manner. For all lineages studied, those of the bone marrow were least disturbed, and/or were first to recover, even during continued drug exposure. 相似文献