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111.
In recent years, named data networking (NDN) has been accepted as the most popular future paradigm and attracted much attention, of which the routing model contains interest forwarding and content delivery. However, interest forwarding is far from the bottleneck of routing optimization; instead, the study on content delivery can greatly promote routing performance. Although many proposals on content delivery have been investigated, they have not considered packet‐level caching and deep traffic aggregation, which goes against the performance optimization of content delivery. In this paper, we propose a packet‐level‐based traffic aggregation (PLTA) scheme to optimize NDN content delivery. At first, the packet format is devised, and data plane development kit (DPDK) is used to ensure same size for each packet. Then, the whole delivery scheme with traffic aggregation consideration is presented. The simulation is driven by the real YouTube dataset over Deltacom, NSFNET, and CERNET topologies, and the experimental results demonstrate that the proposed PLTA has better delivery performance than three baselines in terms of cache hit ratio, delivery delay, network load, and energy efficiency. 相似文献
112.
Zhiyu Hu Fengquan Liu Jian Gao Weidong Zhou Hong Huo Jianjun Zhou Lin Li 《Advanced functional materials》2020,30(5)
Lithium (Li) metal anodes are regarded as a promising pathway to meet the rapidly growing requirements on high energy density cells, owing to their highest gravimetric capacity (3840 mAh g?1) and their lowest redox potential. The application of Li metal anodes, however, is still hindered by undesired dendrites formation and endless consumption of liquid electrolyte due to a continuous reaction on interface of electrolyte/Li‐metal without a stable solid–electrolyte–interface (SEI) layer. A stable protection layer is formed on Li metal anode by in situ transferring the coating layer from polymer separator. The Li anode protection strategy is developed with an in situ formed protection layer transferred through the reduction of a coating layer on polymer separator. A PbZr0.52Ti0.48O3 (PZT) coating layer on polypropylene (PP) separator is reduced by Li metal anode to produce a Pb metal containing composite layer, which could form Pb–Li alloy and adhere to the surface of Li metal anode after the reaction and improves the Li plating/stripping efficiency owing to the formation of a more homogenized electric field. Both the Li/Li symmetric cells and LiFePO4/Li cells with this PZT precoated PP separators exhibit significantly improved Coulombic efficiency and cycling life. 相似文献
113.
Shi Li Rui Wang Yuchi Huo Wenting Zheng Wei Hua Hujun Bao 《Computer Graphics Forum》2020,39(7):181-192
In this paper, we present a new shader smoothing method to improve the quality and generality of band-limiting shader programs. Previous work [YB18] treats intermediate values in the program as random variables, and utilizes mean and variance statistics to smooth shader programs. In this work, we extend such a band-limiting framework by exploring the observation that one intermediate value in the program is usually computed by a complex composition of functions, where the domain and range of composited functions heavily impact the statistics of smoothed programs. Accordingly, we propose three new shader smoothing rules for specific composition of functions by considering the domain and range, enabling better mean and variance statistics of approximations. Aside from continuous functions, the texture, such as color texture or normal map, is treated as a discrete function with limited domain and range, thereby can be processed similarly in the newly proposed framework. Experiments show that compared with previous work, our method is capable of generating better smoothness of shader programs as well as handling a broader set of shader programs. 相似文献
114.
常规变电站正在无人值班改造，但在进行过程中，由于理解的不同，往往产生各种认部分和措施上的差异，使已改造的变电站运行并不理想，本文针对常规变电站在进行无人值班改造的几个关键技术进行分析，并提出相应的解决方法。 相似文献
115.
阐述了应用在便携情报通信设备中的环型可编程开关电容(SC)升降压DC/DC变换器的基本结构和工作原理;用实例说明了3级SC变换器的输出特性;测量了3/2升压型和2/3降压型电路中的主要参数。其中,输出电阻Ro和工作效率η是反映该变换器性能优劣的两个重要指标。在给定实验电路参数下,分别测得Ro为1.5Ω和0.59Ω,η为84.4%和87.1%,充分证明了该电路的优良性能。 相似文献
116.
117.
多倍压整流电路的PSPICE分析与研究 总被引：1，自引：0，他引：1
本文利用电路模拟设计软件对在静电电源设备中广泛使用的高压脉冲信号倍压整流电路进行了特性分析，给出了估算公式。对电路参数的选择作了模拟研究。 相似文献
118.
119.
Wenlong Huo Xiaoyan Zhang Shiyu Hou Yugu Chen Yali Wang Jinlong Yang 《Journal of the American Ceramic Society》2019,102(6):3753-3762
Ultralight ceramic foam materials with high porosity play an important role in increasingly hi-tech areas due to the combinative merit of ceramic material and highly porous structure. So far, it remains challenging to fabricate alumina ceramic foams with extremely high porosity and high specific surface area that are comparable to aerogel materials by employing a low cost, eco-friendly and convenient approach. For the first time, we propose the preparation of aerogel-like ceramic foams with nanoscale cell wall and unprecedentedly high porosity using boehmite sol as both ceramic source and bubble interface stabilizer, based on sol nanoparticles stabilized foams using sodium lauryl sulfate (SDS) as modifier. The obtained ultra-stable sol foams allow for the achievement of bulk foams with ultrathin cell wall with thickness in the range of 30-90 nm, super-high porosity up to 99%, and large specific surface area of 280 m2/g, which is attributed to the well-organized assembly of nanoparticles at the liquid/air interfaces. This novel foam material demonstrates excellent adsorption ability for polar volatile organic gases (VOCs) due to its extremely high porosity and large specific surface area. 相似文献
120.