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921.
In this letter, a new method for sidelobe suppression in non-contiguous orthogonal frequency division multiplexing (NC-OFDM) systems is proposed. Unlike the conventional approach, sidelobes are suppressed by iteratively adjusting the constellation points for the subcarriers that are close to the edges of the used bandwidth. The constellation points corresponding to the maximum sidelobe suppression are chosen for transmission. Simulation results show that the proposed algorithm yields good performance improvement in terms of sidelobe suppression, and does not have a significant impact on the peak-to-average power ratio (PAPR). 相似文献
922.
923.
924.
Rongji Dai Jie Chen Jie Lin Shenyuan Xiao Shi Chen Yulin Deng 《Journal of hazardous materials》2009,170(1):141-143
The reductions of nitrophenols catalyzed by nitroreductase from E. coli in the presence of NADH were investigated in this paper. 4-Aminophenol and 4-hydroxylaminophenol were found in the reductive products of 4-nitrophenol and the maximum reductive ratio was about 83.49% when the reaction time was 70 min; 4,6-dinitro-2-pimelie kelone was found in the reductive products of 2,4-dinitrophenol and the maximum reductive ratio was about 75.28% when the reaction time was 80 min; 2,4-dinitrophenol and 4,6-dinitro-2-pimelie kelone were found in the reductive products of 2,4,6-trinitrophenol and the maximum reductive ratio was about 62.08% when the reaction time was 100 min. The similar reductive ratios of nitrophenols were obtained under aerobic and anaerobic conditions. The results indicated that nitroreductase was an oxygen-insensitive enzyme. 相似文献
925.
Optimal designs for minimising the combination of symbol estimation errors subject to lp-norm constraint are investigated. Instead of considering each constraint in a separate way, the authors develop a unifying framework to obtain the optimal solution by employing a directional derivative method. The sum or peak power constraint turns out to be the case of p=1 or prarrrarr. Simulation results demonstrate the effectiveness of the proposed algorithm. Moreover, based on directional derivative, the authors show that the minimisation of the determinant of the minimum mean-square error (MMSE) matrix and the maximisation of mutual information are equivalent criteria. 相似文献
926.
炼油企业余热锅炉补燃系统电气控制回路设计存在的缺陷,引起一次装置停车事故,只因余热锅炉补燃系统电气控制一开一备两台风机联锁不可靠,在事故状态下不能保证备用电动机起动。分析联锁电路存在的问题,提出合理的术改造措施。 相似文献
927.
The news from Shandong, China, a few days ago, Qingdao Mesnac Co., Ltd. invested 770,000,000 yuan to build China's largest scientific research and manufacturing base for intelligent rubber machinery and pressure vessels, the foundation laying ceremony was held in Jiaozhou city, Shandong Province. The base is located in Jiaodong town of Jiaozhou city, with a total area of 720 hectares, it will be completed in two phases. 相似文献
928.
A novel concentrator used in solar fiber lamp has been designed and made. The method of the design has been introduced. The lamp has been tested under the real solar condition and the experiment curves have been given. The light transmission will be influenced by the structure of the lamp and the diameter of the fiber, which has been studied in this paper. The experimental results show that the brightness of this solar fiber lamp is about the brightness of a 6-W ordinary electrical energy-saving lamp. The computer simulation for the lamp has been presented and the improvement schemes are proposed. 相似文献
929.
用AutoCad VBA处理土地调查数据 总被引:1,自引:0,他引:1
以AutoCad软件为基础的数据处理平台,利用其二次开发工具VBA,连接到Access数据库,实现土地调查数据的自动处理,达到了提高生产效率、控制质量的目的. 相似文献
930.