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11.
12.
自适应RBF神经网络在CDMA移动通信上行链路功率控制中的应用研究 总被引:1,自引:0,他引:1
提出了一种自适应RBF神经网络功率控制方案。详细研究了该网络在DS-CDMA通信中,进行上行链路闭环功率控制(基于信扰比(SIR))的应用理论,给出了该网络参数的计算方法。最后用计算机仿真法模拟出该控制器的运行性能。结果表明基于SIR的自适应RBF神经网络功率控制器能自适应地调整移动台的发射功率,使基站接收信号的信扰比始终非常接近于一个常数,且有比定步长功率控制更小的SIR跟踪误差,从而可以降低接收信号的中断概率、提高信道容量。 相似文献
13.
AN Reshetilov DA Efremov PV Iliasov AM Boronin NI Kukushskin RV Greene TD Leathers 《Canadian Metallurgical Quarterly》1998,13(7-8):795-799
Amperometric biosensors register oxygen depletion in response to analyte catabolism, and thus are limited by the availability of dissolved oxygen. Microbial sensors containing immobilized cells of Gluconobacter oxydans were hyperoxygenated to 400% of control levels and the effects on sensor responses to glucose were determined. Oxygenated perfluorodecalin (a completely fluorinated organic substance) was as effective in hyperoxygenation as direct sparging with O2, increasing sensor base medium oxygen concentrations from 9.3 to 37 mg/l. Hyperoxygenation enhanced maximal biosensor response amplitudes, particularly at high cell loading densities. Maximal response rates were also improved, although less dramatically. Results suggest that hyperoxygenation may be a new general approach for modulating biosensor responses. 相似文献
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脉冲激光沉积SrBi2Ta2O9铁电薄膜电容特性研究 总被引:2,自引:0,他引:2
用PLD方法成功地制备了SBT铁电薄膜,并制作成Pt/SBT/Pt薄膜电容器。SBT薄膜的晶面取向以(008)和(115)为主。在5V电压下,极化反转,并且得到较饱和的电滞回线,剩余极化强度和矫顽电场分别为84μC/cm2和57kv/cm。IV特性测试显示两个对称的双稳峰,并得到零电压下,面积为314×104μm2,厚度为035μm的电容器,电容约为560pF,介电常数约为600。疲劳测试表明Pt/SBT/Pt具有优良的抗疲劳特性。 相似文献
17.
ID Zakharov AM Magasumov NI Simonova IaL E?del''man IuV Simenido 《Canadian Metallurgical Quarterly》1997,90(12):8-12
The authors present results of social and ecologic study carried out in Ufa. The results describe the course of ecologically important processes and phenomena in correlation with the public subjective understanding. Public health is influenced by hygienic parameters of food and water quality as well as a complex of social, economic and psychologic factors. Weak correlation between those parameters and ambient air pollution necessitates more accurate approach to ecologic mapping of cities and to manipulation with data on lower atmosphere pollution with chemical hazards. 相似文献
18.
NI Goldstein M Prewett K Zuklys P Rockwell J Mendelsohn 《Canadian Metallurgical Quarterly》1995,1(11):1311-1318
The epidermal growth factor receptor (EGFR) is a protein tyrosine kinase expressed on many types of tumor cells, including breast, ovarian, bladder, head and neck, and prostatic carcinoma. There seems to be an association between up-regulation of the EGFR and poor clinical prognosis for a number of human cancers. The 225 antibody is a highly specific murine monoclonal antibody that binds specifically to the human EGFR with an affinity equal to its ligand, competes with the ligand for binding, and blocks activation of the receptor tyrosine kinase. In addition, 225 has been shown to inhibit the growth of human tumor xenografts in athymic nude mice. The 225 antibody has recently been chimerized with human IgG1 in its constant region to increase its clinical utility by decreasing the potential for generation of human antimouse antibodies in recipients. This report compares the biological effects of 225 and its chimeric counterpart (designated C225) against established A431 tumor xenografts in nude mice. The results of these experiments indicated that C225 was more effective than 225 in inhibiting tumor growth in this model. In addition, many of the animals treated with C225 were tumor free at the end of each treatment protocol. It was determined that the dissociation constant of C225 was about 5-fold lower than 225. This suggested that the increased capacity of C225 to compete with ligand for binding to the EGFR was responsible for its enhanced in vivo antitumor effect. 相似文献
19.
VA Demenev MA Shchinova LI Ivanov RN Vorob''eva NI Zdanovskaia NV Neba?kina 《Canadian Metallurgical Quarterly》1996,41(3):107-110
Nine female patients with a urethral diverticulum were admitted to our center over a six period: The clinical symptomatology was not specific. The diagnosis has been performed by voiding and retrograde cysto-uretrogram. The surgical treatment consisted in the excision of the diverticula, with the patient in the supine position. No perioperative morbidity was observed. 相似文献
20.
简要介绍了国内少有的干气催化部分氧化转化制氢工艺,重点讨论了转化水碳比的控制条件,对降低水碳比操作进行了有益地探讨。 相似文献