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111.
本文运用语言学理论对印欧语系的原始词根进行了全新的分析和综合,揭示了词根字母排列组合的内在规律、首位字母的宏观倾向性语义及词根语义的相互关系。这有助于加深对印欧语系原始母语的了解,促进对其所派生的现代相关语言的研究。  相似文献   
112.
A handwritten Chinese character recognition method based on primitive and compound fuzzy features using the SEART neural network model is proposed. The primitive features are extracted in local and global view. Since handwritten Chinese characters vary a great deal, the fuzzy concept is used to extract the compound features in structural view. We combine the two categories of features and use a fast classifier, called the Supervised Extended ART (SEART) neural network model, to recognize handwritten Chinese characters. The SEART classifier has excellent performance, is fast, and has good generalization and exception handling abilities in complex problems. Using the fuzzy set theory in feature extraction and the neural network model as a classifier is helpful for reducing distortions, noise and variations. In spite of the poor thinning, a 90.24% recognition rate on average for the 605 test character categories was obtained. The database used is CCL/HCCR3 (provided by CCL, ITRI, Taiwan). The experiment not only confirms the feasibility of the proposed system, but also suggests that applying the fuzzy set theory and neural networks to recognition of handwritten Chinese characters is an efficient and promising approach.  相似文献   
113.
利用神经元芯片CY7C53120和单片机AT89S52设计了基于主机的智能楼宇用电参数采集Neuron节点,构成了LonWorks网络系统,采用AD637实现了电流与电压的真有效值高精度转换,给出了其硬件及软件模块。测试结果表明,系统实现了对楼宇中各用电参数的在线测量,误差控制在±1%以内。  相似文献   
114.
In this paper, an accelerated iteration method for simultaneously determining of a polynomial equation's roots is proposed. The new method is an improvement of modified Newton method. At the same time, convergence properties and the order of convergence rate are discussed. At last, some numerical results are reported and listed.  相似文献   
115.
玉米根系几何造型研究   总被引:13,自引:1,他引:13  
通过对玉米根系形态建成过程根系的结构、生长及分布特点和规律观测研究,构建了描述玉米根系形态变化的数学模型。结合粒子系统和计算机图形学技术,在计算机上实现了玉米根系生长的三维显示。其结果和实际的玉米根系的生长发育过程基本一致,为农学研究者提供了一个可视化的根系模型。本模型结构简单、可交互、真实感强,可以较好地虚拟玉米根系的生长过程。  相似文献   
116.
文章研究了线性同余序列参数的生成方法,并给出了具体的求乘数算法。  相似文献   
117.
以流动注射悬浮脉冲进样-火焰原子吸收光谱法进行了中草药生地中铁和锌元素的测定,生地被干燥,粉碎,过筛后加入琼脂溶液制成悬浮液,然后用流动注射脉冲送入雾化器。实验考察了仪器工作条件,样品悬浮液制备和方法的准确性,用标准加入法测定,该法简便,快捷,测定结果与灰化法一致。  相似文献   
118.
Growth rings were used to determine the root age of medicinal Paeonia lactiflora from four producing areas, and their corresponding paeoniflorin content were measured based on the identification of ages. Different P. lactiflora root samples of different ages were collected from the four major growing areas in China: Bozhou, Anhui Province; Pan'an, Zhejiang Province; Zhongjiang, Sichuan Province; and Heze, Shandong Province. The relationship between the number of growth rings and age was analyzed using hand sections and paraffin sections. The paeoniflorin content in the roots of different P. lactiflora cultivars from different growing areas was measured using high‐performance liquid chromatography (HPLC). The growth rings in the P. lactiflora roots were consistent with the age of the plant from Heze, Zhongjiang, Pan'an, whereas that for the P. lactiflora from Bozhou was one less than the age of the plant. The HPLC results show that the paeoniflorin content was highest in P. lactiflora ‘Baihuachuanshaoyao,’ followed by ‘Baihuahangshaoyao,’ ‘Honghuachuanshaoyao,’ and ‘Honghuahangshaoyao,’ ‘Bozhoushaoyao’ had the lowest levels of paeoniflorin. With increasing age, the paeoniflorin in the roots of the different P.lactiflora cultivars slowly declined or remained the same. In summary, the age of the roots of P. lactiflora from different growing areas can be determined using growth rings. The paeoniflorin content in the roots of P. lactiflora is correlated with cultivar and it was slowly declined with increasing age. Microsc. Res. Tech. 75:1191–1196, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
119.
Chitosan-impregnated gutta-percha points (ChitGPP) were tested for their ability to inhibit the growth of microorganisms usually involved in root canal infections. Their mechanical properties were also studied and compared with the commonly used commercial points in endodontics. ChitGPP were more efficient in reducing the microbial load than those without chitosan. ChitGPP also possess better tensile and elastic properties than commercial ones. After six months of storage, ChitGPP’s were still able to reduce the bacterial load by 1 log, suggesting that impregnation of gutta-percha points with chitosan could be a good alternative to obtain gutta-percha points with improved antimicrobial properties.  相似文献   
120.
Diabetes mellitus (DM) is a common chronic medical problem worldwide; one of its complications is painful peripheral neuropathy, which can substantially erode quality of life and increase the cost of management. Despite its clinical importance, the pathogenesis of painful diabetic neuropathy (PDN) is complex and incompletely understood. Voltage-gated sodium channels (VGSCs) link many physiological processes to electrical activity by controlling action potentials in all types of excitable cells. Two isoforms of VGSCs, NaV1.3 and NaV1.7, which are encoded by the sodium voltage-gated channel alpha subunit 3 and 9 (Scn3A and Scn9A) genes, respectively, have been identified in both peripheral nociceptive neurons of dorsal root ganglion (DRG) and pancreatic islet cells. Recent advances in our understanding of tetrodotoxin-sensitive (TTX-S) sodium channels NaV1.3 and NaV1.7 lead to the rational doubt about the cause–effect relation between diabetes and painful neuropathy. In this review, we summarize the roles of NaV1.3 and NaV1.7 in islet cells and DRG neurons, discuss the link between DM and painful neuropathy, and present a model, which may provide a starting point for further studies aimed at identifying the mechanisms underlying diabetes and painful neuropathy.  相似文献   
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