期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
挥发金属β-二酮化合物质量传输过程的试验研究
1
作者 潘水艳 卓钺 杨盛良 《冶金分析》 CAS CSCD 北大核心 2004年第z2期584-586,共3页
为了确定以乙酰丙酮铱这种金属β-二酮化合物为沉积源的金属铱MOCVD的具体工艺参数,针对基体面积较大或不规则的工艺条件,本文自行设计了能在不同温度下适时采集数据的微量失重-时间数据采集记录仪,进行了以Ar气为载气,温度在220℃-250... 为了确定以乙酰丙酮铱这种金属β-二酮化合物为沉积源的金属铱MOCVD的具体工艺参数,针对基体面积较大或不规则的工艺条件,本文自行设计了能在不同温度下适时采集数据的微量失重-时间数据采集记录仪,进行了以Ar气为载气,温度在220℃-250℃之间的乙酰丙酮铱质量传输过程的试验研究,发现质量传输速度不仅与载气、温度有关,而且与有效表面积有关.实验给出了了相关温度下质量传输速度的有关数据. 展开更多
关键词 金属β-二酮化合物 乙酰丙酮铱 质量传输速率
下载PDF
Energy Efficient Power Allocation Scheme for Distributed Antenna Systems with Target BER Constraint
2
作者 Xiangbin Yu Ying Wang +2 位作者 Qiuming Zhu Tao Dong Junya Chu 《China Communications》 SCIE CSCD 2016年第11期234-243,共10页
The energy efficiency(EE) of distributed antenna system with quality of service(Qo S) requirement is investigated over composite Rayleigh fading channel,where the shadow fading,path loss and Rayleigh fading are all co... The energy efficiency(EE) of distributed antenna system with quality of service(Qo S) requirement is investigated over composite Rayleigh fading channel,where the shadow fading,path loss and Rayleigh fading are all considered. Our aim is to maximize the EE which is defined as the ratio of the transmission rate to the total consumed power subject to the maximum transmit power of each remote antenna constraint and Qo S(target BER) requirement. According to the definition of EE and using the upper bound of average EE,the optimized objective function is provided. Based on this,utilizing Karush-KuhnTucker conditions and numerical calculation,a suboptimal energy efficient power allocation(PA) scheme is developed,and the closedform expression of PA coefficients is derived. The scheme may obtain the EE performance close to the existing optimal scheme. Moreover,it has relatively lower complexity than the existing scheme because only the statistic channel information and less iteration are required. Simulation results show the presented scheme is valid and can meet the target BER requirement,and the EE can be increased as target BER requirement decreases. 展开更多
关键词 distributed antenna system energy efficiency power allocation target bit error rate(ber) shadow fading path loss
全文增补中
上一页 1 下一页 到第
使用帮助 返回顶部