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111.
针对印染废水水质水量变化大、可生化性差、COD和色度去除不稳定和脱氮效率低等问题,采用高效厌氧处理、生物强化处理以及深度处理技术路线,开发了折流式厌氧水解(ABR水解)-A/O(PACT)-深度处理工艺,建立了中试研究基地和示范工程,根据处理规模为2万m3/d的示范工程处理效果,出水COD、总氮、氨氮、总磷和色度去除率分别为90.9%、78.5%、89.2%、92.2%和91.4%,出水水质可稳定达到《太湖地区城镇污水处理厂及重点工业行业主要水污染物排放限值》(DB 32/1072—2007),工程投资为1 650元/m3,直接运行费用1.7元/m3。 相似文献
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Medium access control in ultra-wideband wireless networks 总被引:7,自引:0,他引:7
Xuemin Shen Weihua Zhuang Hai Jiang Jun Cai 《Vehicular Technology, IEEE Transactions on》2005,54(5):1663-1677
Ultra-wideband (UWB) transmission is an emerging wireless communication technology with unique potential merits such as high-rate, low-transmission power, immunity to multipath propagation, and capability in precise positioning. It has received significant interests for future wireless communications from both academia and industry. In UWB wireless networks, medium access control (MAC) is essential to coordinate the channel access among competing devices. The unique UWB characteristics not only pose significant challenges but also offer great opportunities in efficient UWB MAC design. This paper presents a comprehensive overview of UWB MAC development on four important aspects: multiple access, overhead reduction, resource allocation, and quality of service (QoS) provisioning, and identifies some future research issues. 相似文献
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“大成智慧学”是新世纪的需要,“必集大成 ,才能得智慧!”“大成智慧”的核心是科学与哲学的结合。为此,不仅要利用人——机结合的思维体系,下苦功夫掌握广博的知识、经验、信息,还要从实际出发,实事求是,善于思考,反复实践,努力树立起反映新世纪的世界观、人生观、科学观、方法论。 相似文献
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Hai Jiang Weihua Zhuang Xuemin Shen 《Communications Magazine, IEEE》2005,43(12):120-126
Cross-layer design approaches are critical for efficient utilization of the scarce radio resources with QoS provisioning in the third-generation wireless networks and beyond. Better system performance can be obtained from information exchanges across protocol layers, which may not be available in the traditional layering architecture. This article provides an overview of cross-layer design approaches for resource allocation in 3G CDMA networks, summarizes state-of-the-art research results, and suggests further research issues. In addition, a cross-layer design approach for real-time video over time-varying CDMA channels is proposed, where link layer resource allocation benefits from information in both the application and physical layers. Simulations results are given to demonstrate the effectiveness of the proposed approach. 相似文献
120.
Yujie Tang Yongkang Liu Ning Zhang Jon W. Mark Xuemin Shen 《Wireless Communications and Mobile Computing》2016,16(9):1050-1064
In this paper, a cluster‐based two‐phase coordination scheme for cooperative cognitive radio networks is proposed considering both spectrum efficiency and network fairness. Specifically, candidate secondary users (SUs) are first selected by a partner selection algorithm to enter the two‐phase cooperation with primary users (PUs). In phase I, the selected SUs cooperate with PUs to acquire a fraction of time slot as a reward. In phase II, all SUs including the unselected ones share the available spectrum resources in local clusters; each of which is managed by a cluster head who participated in the cooperation in phase I. To improve the total network utility of both PUs and SUs, the maximum weighted bipartite matching is adopted in partner selection. To further improve the network performance and communication reliability, network coding is exploited during the spectrum sharing within the cluster. Simulation results demonstrate that, with the proposed cluster‐based coordination scheme, not only the PUs' transmission performance is improved, but also SUs achieve spectrum access opportunities. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献