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101.
102.
定义了描述信号分离状态的一种测度,并在认真分析相关固定步长和变步长EASI算法的基础上。提出了一种新的步长自适应等变化自适应(EASI)算法。该算法步长是基于分离状态的。其学习速率由信号的分离程度自适应地选取。因而能很好地解决收敛速度和稳态误差之间的矛盾。计算机仿真结果与理论分析相一致,证实了该算法明显优于传统的EASI算法. 相似文献
103.
104.
固体热容激光器的设计和功率标定 总被引:2,自引:0,他引:2
固体热容激光器(SSHCL)作为下一代最佳候选高功率激光器,引起人们广泛关注。介绍了固体热容激光器工作原理、光抽运期间介质板内荧光分布和温度分布、介质板冷却以及功率标定。详细讨论了激光介质温度对激光输出功率的影响,对有关设计要点也作了相关分析。 相似文献
105.
根据量子力学中态的叠加原理,构造了N维希尔伯特空间多模复共轭相干态|{iZj^*}〉2q,多摸复共轭虚相干态|{iZj^*}〉2q,及多模真空态|{Oi}〉2q三态叠加而成的多模纠缠态光场|ψ^(3)〉2q。研究了态|ψ^(3)〉2q的任意次广义非线性等幂次N次方差压缩特性。结果表明,N维希尔伯特空间中不存在态|ψ^(3)〉2q的等幂次N次方差压缩,态|ψ^(3)〉2q处于N-X最小测不准态的纠缠相干态。进而指出,只有压缩次数小于空间维数时,态|ψ^(3)〉2q有可能呈现差压缩效应。 相似文献
106.
Cheng Bo Guo Jie Chen Junliang Meng Xiangwu 《International Journal of Communication Systems》2009,22(6):773-787
Development of services that span over the Internet and Telecom networks is driving significant efforts towards the integration of services offered by Telecom operators. The telecommunications R&D community also starts adapting and developing similar service delivery platforms to offer a wide range of new value‐added services faster and more cost efficiently inspired by the success of Web service technologies for the development and deployment of IT services. In this paper, we have an analysis for Telecom Web services communication requirements and also propose Telecom Web services communication model considering the specific characteristics as state, asynchronous, event‐driven communications in Telecom domain. We focus on the design and implementation details for real‐time Web service communication model in Telecom domain, and as the framework of communication model for Telecom Web services, the enhanced state machine design and implementation, and the messages dispatching design and implementation for Telecom Web services communication model, and also illustrate the third party end call control scenarios. Finally, we give the conclusion and future essential work. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
107.
108.
Xiaofeng Bai Abdallah Shami Serguei Primak 《Wireless Communications and Mobile Computing》2012,12(13):1215-1224
We consider the minimization of long‐term average power consumption for packet transmission between a mobile station and the base station over Nakagami‐m fading channel. Power consumption is minimized by intelligent transmission scheduling design, with the average queuing delay and joint packet loss across MAC and physical layers being confined below certain levels. The problem is formulated as an infinite horizon constrained Markov decision problem and solved by linear programming (LP) method. The primary intention of this paper is to provide a visible paradigm on using LP method to optimize the performance of mobile wireless communication systems. We elaborate the detailed mathematical solution with consistent simulation experiments and emphasize the effectiveness of adaptive transmission scheduling for cross‐layer QoS provisioning. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
109.
对比传统的平面型晶体管,总结了三维立体结构FinFET器件的结构特性。结合MOS器件栅介质材料研究进展,分别从纯硅基、多晶硅/高k基以及金属栅/高k基三个阶段综述了Fin-FET器件的发展历程,分析了各阶段FinFET器件的材料特性及其在等比缩小时所面临的关键问题,并着重从延迟时间、可靠性和功耗三方面分析了金属栅/高k基FinFET应用于22 nm器件的性能优势。基于短沟道效应以及界面态对器件性能的影响,探讨了FinFET器件尺寸等比缩小可能产生的负面效应及其解决办法。分析了FinFET器件下一步可能的发展方向,主要为高迁移率沟道材料、立体型栅结构以及基于新原理的电子器件。 相似文献
110.
High dielectric constant materials have a crucial importance for various microelectronic applications such as memory devices, supercapacitors etc. Among other insulators, perovskite structured oxide materials attract great interest not only for their high dielectric constants but also their unique electrical and magnetic properties such as superconductivity etc. From this point of view, a new Europium based copper oxide layered material with perovskite structure (EuBa2Ca2Cu3O9−x coded as Eu-1223) has been synthesized by solid state reaction method in this work. The physical and chemical properties of Eu-1223 have been determined by FTIR, SEM, XRF, XRD, TGA and DTA techniques. The influence of temperature on impedance and dielectric properties of Eu-1223 has been investigated by impedance spectroscopy measurements performed within the frequency interval of 5 Hz–13 MHz between 298 K and 408 K temperatures. It has been found that the Eu-1223 material has high dielectric constants at each temperature operated. In addition, Eu-1223 sample behaves as a colossal dielectric material up to 300 kHz for 408 K due to observation of dielectric constant values which are greater than 103. Furthermore, it has been revealed that Eu-1223 material can be used as thermally sensitive resistors in electronic circuits due to its decreasing resistance with increasing temperature. Moreover, it has been observed that the relaxation frequency of the system shifts from 46.5 kHz (low frequency radio wave band) to 1.57 MHz (mid frequency radio wave band) as the temperature increasing from 298 K to 408 K. According to dc conductivity investigations, the variation of dc conductivity with the inverse of temperature satisfies linear relationship that indicates a thermally activated nearest neighbor hopping conduction. On the other hand, it has been determined that ac conductivity has frequency dependent relation which obeys ωs for the high frequency region. Furthermore, the frequency exponent, s, which takes values between 0.7 and 0.4, shows a decreasing behavior with increasing temperature. In conclusion, ac charge transport mechanism has been predicted as correlated barrier hoping for Eu-1223. 相似文献