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61.
陈紫莎 《泉州师范学院学报》2001,19(4):86-88
针对极限概念的抽象性,通过实例教学,使学生较容易直观认识数列“特征”的定义,由浅入深,过渡到对数列“ε-N”定义的理解和掌握,从而获得良好的教学效果。 相似文献
62.
MA Zhenying(College of Computer Science of Chongqing University, Chongqing 400044) 相似文献
63.
杨定中 《郧阳师范高等专科学校学报》2005,25(3):32-34
指针是C语言中的精华,也是C语言一个重要特色.从指针与指针变量,还有数组指针与指针数组,函数指针与指针函数等方面分析了与“指针”有关的数据类型. 相似文献
64.
A low-sidelobe circularly-polarized (CP) microstrip patch array for 2.4 GHz radio frequency identification (RFID) readers is presented. The antenna array with a Chebyshev current distribution is composed of 6 microstrip elements. The CP operation is obtained by the quasi-square patch with difference in lengths of the two sides. The antenna has been investigated numerically and experimentally. Measured results show that the array has a Chebyshev pattern with the sidelobe level of -23 dB, the half-power beamwidth of 16° and an impedance bandwidth (S11 ≥-10 dB) of 130 MHz, which is suitable for RFID reader applications. 相似文献
65.
依托Java语言环境实际程序代码,对Java环境下数组和链表的效率问题进行测试,得到与经典教材不同的结果. 相似文献
66.
Jin QC Dong HT Peng YL Chen BS Shao J Deng Y Dai CE Fang YQ Lou YC Li YZ Li DB 《Journal of Zhejiang University. Science. B》2007,8(2):88-97
Appressorium is an infection structure of the phytopathogenic fungus Magnaporthe grisea. Analysis of gene expression profiles ofappressorium development provides insight into the molecular basis of pathogenicity and control of this fungal plant disease. A cDNA array representing 2927 unique genes based on a large EST (expressed sequence tag) database ofM. grisea strain Y34 was constructed and used to profile the gene expression patterns at mycelium and appressorium maturation stages. Compared with mycelia, 55 up-regulated and 22 down-regulated genes were identified in mature appressoria. Among 77 genes, 16 genes showed no similarity to the genome sequences of M. grisea. A novel homologue of peptidyl-prolyl cis-trans isomerase was found to be expressed at low-level in mature appressoria of M. grisea. The results indicated that the genes such as pyruvate carboxylase, phospholipid metabolism-related protein and glyceraldehyde 3-phosphate dehydrogenase involved in gluconeogenesis, lipid metabolism and glycolysis, showed differential expression in mature appressoria. Furthermore, genes such as PTHll, beta subunit of G protein and SGTI involved in cell signalling, were expressed differentially in mature appressoria. Northern blot analysis was used to confirm the cDNA array results. 相似文献
67.
以消除直流偏磁为突破点,提出了应用于四相电压调整模块(VRM)的阵列式集成磁件。研究了VRM的稳态电流及动态响应受阵列式集成磁件各电感耦合系数的影响;利用“场”、“路”结合的方法分析了阵列式集成磁件消除直流偏磁的原理;推导得到了阵列式集成磁件等效电路;设计了阵列式集成磁件的实现结构,并给出了阵列式集成磁件的电磁设计方法。 相似文献
68.
Yi Yu Shao-min Zhang Huai-jian Zhang Xiao-chun Liu Qiao-sheng Zhang Xiao-xiang Zheng Jian-hua Dai 《Journal of Zhejiang University. Science. B》2010,11(4):298-306
Brain-machine interface (BMI) has been developed due to its possibility to cure severe body paralysis. This technology has been used to realize the direct control of prosthetic devices,such as robot arms,computer cursors,and paralyzed muscles. A variety of neural decoding algorithms have been designed to explore relationships between neural activities and movements of the limbs. In this paper,two novel neural decoding methods based on probabilistic neural network (PNN) in rats were introduced,the PNN decode... 相似文献
69.
目前的宽视角的接收一般采用视角分割,以使用多探测器或者复杂接收系统(如光纤阵列)等方式获得,但以上方式主要用于光电对抗的方位探测,在空间激光通信等场合难以适用。基于空间激光通信领域,结合目前宽视角光学接收天线的研究和进展情况,比较分析了现有的技术后,综合考虑视角、光学增益及像差大小,提出一种系统的新思路,针对宽视角、大口径接收面积的指标需求,以小接收面积光电探测器、阵列化天线为约束前提,力争结构简单、经济合理,为后续的深入研究打下良好的基础。 相似文献
70.