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Spectrum‐efficiency enhancement in small cell networks with biasing cell association and eICIC: An analytical framework 下载免费PDF全文
Load balancing and interference management play crucial roles in small cell network (SCN) capacity and spectrum efficiency (SE) enhancement. By performing load balancing between macrocell and small cells, biasing cell association has attracted great attentions since it is proposed. Additionally, enhanced intercell interference coordination (eICIC) technology is also developed as an efficient interference mitigation method for the biasing cell association‐based SCNs. In this paper, we develop an SE enhancement framework with joint consideration of the eICIC factor and biasing factor. Using the stochastic geometry theory, the network is modeled by spatial Poisson point process. We firstly derive the downlink average rate, which is performed at a typical user. Secondly, the eICIC factor‐related network SE is analyzed by proving the existence of optimal eICIC factor, which maximizes the network SE. For the intractability of the closed‐form expression of optimal eICIC factor, a bisection search‐based algorithm is developed then. At last, numerical results confirm our analysis and show the proposed algorithm performance. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Houwen Tang M. A. Matin Heli Wang Shet Sudhakar Le Chen Mowafak M. Al-Jassim Yanfa Yan 《Journal of Electronic Materials》2012,41(11):3062-3067
A major drawback for CuO as an efficient photocathode in photoelectrochemical (PEC) water splitting is its instability in aqueous solution. In this paper, we report that Ti alloying can enhance the stability of CuO in PEC water splitting but at the cost of reduced crystallinity and optical absorption, and therefore reduced photocurrent. We further report that a balance between the stability and photocurrent can be realized by a bilayer configuration—a thin Ti-alloyed CuO layer on a pure CuO thin film. Our results indicate that the thickness of the top Ti-alloyed CuO layer should be optimized to realize the best stability and photocurrent. 相似文献
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以赤星病原菌Alternaria longipes为筛选指示菌,采用平板共培养初筛和发酵上清滤液复筛的方法,筛选了烟草赤星病拮抗芽胞杆菌3株。其中菌株K11的菌体径向生长抑制率(PIRG)为63.64%,发酵上清滤液的PIRG值达67.44%。盆栽试验证明,该菌对烟草赤星病具有良好的拮抗能力。经鉴定菌株K11为枯草芽胞杆菌(Bacillus subtilis)。由单因素实验和正交实验优化得到了K11菌株生物量较高的摇瓶发酵培养基配方:葡萄糖20.0 g/L,豆粕30.0 g/L,K2HPO4·3H2O 1.0 g/L,MgSO4·7H2O 0.1 g/L。优化后生防菌株K11的生物量比对照提高6.5倍,生物量高达1.28×1010 CFU/mL,芽胞形成率在95%以上。 相似文献
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通过对育苗池底施加不同功率的地热线,拟探索通过苗床加热提高漂湿育苗营养液和盘面温度满足烟苗生长发育,为恩施烟区培育适时烟草壮苗提供科学的育苗方法。研究结果表明,育苗池底铺加地热线均能提高育苗温度和烟苗的生长速度,有效缩短烟苗育苗时间,促进了烟苗生物量的积累,烟苗的整体素质有一定提高。因此,结合恩施烟区地理特征,低山、二高山和高山烟区可分别在育苗池内底部铺加10、20和40 W/M2功率地热线加热,满足烟苗生长所需的温度条件,确保烟苗适时移栽。 相似文献
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Heli Koivuluoto Andrew Coleman Keith Murray Martin Kearns Petri Vuoristo 《Journal of Thermal Spray Technology》2012,21(5):1065-1075
Cold spraying enables high quality Cu coatings to be deposited for applications where high electrical and/or thermal conductivity is needed. Fully dense Cu coatings can provide an effective corrosion barrier in specific environments. The structure of cold-sprayed Cu coatings is characterized by high deformation which imparts excellent properties. Coating properties depend on powder, the cold spray process and post treatments. First of all, powder characteristics have a strong influence on the formation of pure coatings. Secondly, cold spraying provides dense, adherent, and conductive coatings by using HPCS and LPCS. Furthermore, an addition of Al2O3 particles to the Cu powder in LPCS process significantly improves coating properties. Also, heat treatments improve electrical conductivity. This study summarizes optimal characteristics of Cu powder optimized for cold spraying, achieving high coating quality and compares properties of HPCS Cu, LPCS Cu and Cu+Al2O3 coatings prepared from the same batch of OFHC Cu powder. 相似文献