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51.
The dual‐branch selection‐and‐stay combining (SSTC) is analyzed for diversity reception on independent and correlated Nakagami‐m fading channels, where the conventional selection combining (SC) is employed only at the switching instance, and the receiver uses the selected branch till its signal‐to‐noise ratio (SNR) estimation is lower than a preset threshold. In this combining scheme, the receiver only needs to continuously estimate the SNR of the single selected branch. For the performance analysis of SSTC, the switching rate and the average bit error rates (BERs) of different binary coherent and non‐coherent modulations are evaluated. Numerical results based on the analysis and simulations are illustrated. According to the analysis and numerical results, the SSTC outperforms the existing switch‐and‐stay combining in the senses of the average BER and switching rate. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
52.
介绍通信线缆的应用现状,提出应重视通信线缆的阻燃性能,并通过对CM、CMR、CMP和LSOH线缆进行燃烧实验对比其阻燃性能,实验证明CMP线缆具有在最短时间内自我熄灭且不续燃的功能。 相似文献
53.
The display image of a PC can be reconstructed by using the conducted emission on the PC's network cable. The relevant signals which be used to reconstruct the original image are coupling from the radiation of the switching of red, green, blue (RGB) signals in PC. These pertinent signals are partly contained in the frequency region higher than 30 MHz in the conducted emission. From these findings, the near-field coupling principle from PC to the network cable is analyzed firstly. And then, a multi-conductor transmission model for the RGB signals which transmit in the network cable is proposed. In addition, the maximum safe distance is estimated by using this model. In order to check the validity of the estimating distance, the eavesdropping experiment is carried out to reconstruct the original display image. The results demonstrate that the blurred display image can be retrieved at the place of 29.5 m. 相似文献
54.
Claude J. RENAUD Xuling LIN Srinivas SUBRAMANIAN Dale A. FISHER 《Hemodialysis international. International Symposium on Home Hemodialysis》2011,15(1):63-68
Methicillin‐sensitive Staphylococcus aureus (MSSA) bacteremia is a leading cause of infection in hemodialysis (HD) patients. Cloxacillin, cefazolin, and vancomycin are the mainstay antimicrobials. Cloxacillin administration leads to frequent drug dosing, longer length of stay (LOS), and higher cost, while resistance and poorer outcomes are associated with vancomycin use. Dosing cefazolin during HD allows for prolonged blood therapeutic levels. We assessed the outcomes and safety of a strategy of treating MSSA bacteremia with 2–3 g cefazolin on HD only. All HD patients with MSSA bacteremia admitted in June–December 2009 at our center and receiving this regime were compared with historical controls who received cloxacillin. Demographic characteristics and outcome measures like mortality, LOS, cost, recrudescence, and adverse drug reactions were assessed. Of 27 consecutive episodes reviewed, 14 and 13 patients received cefazolin and cloxacillin, respectively. Baseline demographics were comparable between the 2 treatment groups. More than one‐third of the bacteremia was related to tunneled catheter infection. The 30‐day mortality of cloxacillin‐ and cefazolin‐treated patients was 15% and 7%, respectively (P=0.14). Two of the 11 survivors treated with cloxacillin (18%) had recrudescent bacteremia while none was observed in cefazolin‐treated survivors. Cefazolin was associated with shorter LOS (10 vs. 20 days, P<0.05) and lower cost (US$8262.00 vs. US$15,367.00, P<0.05). Cefazolin use resulted in 3 idiosyncratic adverse drug reactions. Cefazolin dosed on each HD in MSSA bacteremia leads to earlier discharge and less cost. Larger prospective studies are, however, warranted to fully assess its safety and efficacy. 相似文献
55.
Kazumitsu Nawata Masako Ii Aya Ishiguro Koichi Kawabuchi 《Mathematics and computers in simulation》2009
We analyze the length of hospital stays of patients hospitalized for cataract and related diseases (Diagnosis Related Groups (DRG) 2041) in Japan, utilizing the data pertaining to 3436 patients on whom one-eye lens operations are performed. We use the discrete-type proportional hazard model to analyze variables that may affect the length of stay. 相似文献
56.
57.
在分析构件应力状态基础上,通过总结已做的打压试验,从设计、制造和安装出发,考虑蜗壳和座环今后结构的发展趋势,参照国外近年来发表的有关文献,作者提出:在保证焊接质量并认真进行焊缝检验的条件下不可不进行劳民伤财的蜗壳座环现场打压试验。 相似文献
58.
Chun‐Wen Paul Huang Atef Z. Elsherbeni Charles E. Smith Po‐Leng Chin 《国际射频与微波计算机辅助工程杂志》2002,12(2):148-158
Ribbon cables have been widely used as subsystem interconnections in a large number of digital systems, because they can convey numerous bits of a digital signal simultaneously. In this article, finite difference and finite difference time domain (FDTD) methods are used to analyze and optimize the electrostatic analysis design of ribbon cables, and measurements are used to verify the numerical results. © 2002 Wiley Periodicals, Inc. Int J RF and Microwave CAE 12: 148–158, 2002. 相似文献
59.
本文介绍了莲花水站站水轮机座环和蜗壳采用了先进的设计、制造和安装工艺等手段,为该机组的稳定运行奠定了基础。 相似文献
60.
通过非铠装,具有隔磁措施的钢丝铠装和全钢丝铠装单芯交联聚乙烯(XLPE)绝缘电力电缆的模拟负载对比试验,证明单芯钢丝铠装电缆中的钢丝铠装结构,无论是否隔磁措施,都会产生大量的铠装损耗,大大降低电缆的载流量水平,严重时,可导致电缆热击穿。 相似文献