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161.
Liu X.Zhang S.Shan X. 《复杂系统与复杂性科学》2023,(1):81-87
Exploring complementary technology convergence and similar technology convergence is conducive to enhancing enterprise innovation capability. This paper analyzes the impact of partner diversity on technology convergence by building a multi-layer network model of organizational cooperation and technology convergence. The research shows that the geographic diversity of partners is not conducive to the occurrence of complementary technology convergence and similar technology convergence. The technological diversity of partners is conducive to complementary technology convergence but not conducive to similar technology convergence. The relationship strength between enterprises and different types of partners has different effects on complementary technology convergence and similar technology convergence. The research results can help enterprises choose appropriate partners to achieve different innovation strategies. © 2023 Editorial Borad of Complex Systems and Complexity Science. All rights reserved. 相似文献
162.
Journal of Systems Science and Complexity - Complexity is commonly summarized as ‘the actions of the whole are more than the sum of the actions of the parts’. Understanding how the... 相似文献
163.
研究了人工神经网络方法(NN)在生物医学工程和生命科学中的应用。提出了改进反传算法(MBP)并用于肺癌早期诊断:发现其对几类病人的识别和预测时,分类正确率高,临床诊断预测力强。 相似文献
164.
165.
Summary Plant disease may cause a variety of changes in plants which influence their suitability to insect herbivores. The reported physiological changes in tobacco due to infection by tobacco mosaic virus have the potential to influence the feeding, growth and behavior of the tobacco hornworm,Manduca sexta. However, feeding on foliage of systematically infected plants had no statistically significant effects on development time, mean pupal weight or the amount of foliage consumed by 4th instars. Although an initial preference was exhibited by larvae for healthy leaves after about 72 h no differences were observed. These results do not support the results of previous research on the influence of tobacco mosaic virus-infected plants on the tobacco hornworm.Scientific contribution No. 8130, article No. A-5071, of the Maryland Agricultural Experiment Station, Department of Entomology 相似文献
166.
梁晓燕 《科技情报开发与经济》2004,14(6):214-215
通过与传统会计信息系统的比较,分析了计算机网络会计信息系统及网络财务所具有的特点,阐述了计算机网络会计信息系统在网络财务管理中所起的作用。 相似文献
167.
Induction of calcium currents by the expression of the alpha 1-subunit of the dihydropyridine receptor from skeletal muscle 总被引:21,自引:0,他引:21
E Perez-Reyes H S Kim A E Lacerda W Horne X Y Wei D Rampe K P Campbell A M Brown L Birnbaumer 《Nature》1989,340(6230):233-236
The dihydropyridine (DHP) receptor purified from skeletal muscle comprises five protein subunits (alpha 1, alpha 2, beta, gamma and delta) and produces Ca2+ currents that are blocked by DHPs. Cloning of the alpha 1- and alpha 2-subunits, the former affinity-labelled by DHP, has shown that the alpha 1-subunit is expressed in skeletal muscle alone, whereas the alpha 2- and delta- subunits are also expressed in other tissues. Although the transient expression of the alpha 1-subunit in myoblasts from dysgenic mice (but not in oocytes) has been demonstrated, the use of these expression systems to determine the function of the alpha 1- subunit is complicated by the presence of endogenous Ca2+ currents, which may reflect the constitutive expression of proteins similar to the alpha 2-, beta-, gamma- and/or delta-subunits. We therefore selected a cell line which has no Ca2+ currents or alpha 2- subunit, and probably no delta-subunit for stable transformation with complementary DNA of the alpha 1- subunit. The transformed cells express DHP-sensitive, voltage-gated Ca2+ channels, indicating that the minimum structure of these channels is at most an alpha 1 beta gamma complex and possibly an alpha 1- subunit alone. 相似文献
168.
梁新文 《科技情报开发与经济》2004,14(6):185-186
给出了圆柱蜗杆及蜗轮轮齿在任意半径处弦齿厚计算的精确公式,采用了圆球法测量蜗轮直径方向的两齿间距,为了计算上的需要,引进了蜗轮弦齿厚计算斜齿轮的概念和斜齿轮测量圆棒跨距法。 相似文献
169.
加筋土技术的理论研究与工程应用 总被引:5,自引:0,他引:5
概述了加筋技术的概念、应用领域、特点和发展。介绍了国内外加筋机理的理论研究和设计方法,以及在工程中大量采用的加筋挡墙、加筋土坡、加筋土垫层的设计方法和应用特点。 相似文献
170.
Physiological importance of omega-3/omega-6 polyunsaturated fatty acids in man. An overview of still unresolved and controversial questions 总被引:1,自引:0,他引:1
The 'essentiality' of (omega-6) and (omega-3) fatty acids in mammals is well known. Nevertheless, some important points remain unclear concerning their implication in physiology. After a short discussion about the definition of essential fatty acids deficiency, this brief overview deals with some of these points, pointing out some of the unresolved questions. Different subjects are approached concerning the (omega-6) and (omega-3) fatty acids metabolism: desaturases, eicosanoids, production, as well as some of their metabolic effects on cell membranes, intestinal function, glucose and lipid metabolism, haemorheology. 相似文献