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61.
建立完善有效的短消息中心容灾备份系统是保障短消息业务正常开展的必不可少的一项重要措施。本文将对基于分级流量控制中心技术的短信池(SMSCP001)容灾备份解决方案进行研究,并分析其在现网应用的可行性。  相似文献   
62.
MSC池(MSCin Pool)是由3GPP规范定义的,能优化整个移动网络的组网。本文简要介绍了MSC Pool技术的基本原理及其组网特点,分析了MSC Pool所用到的关键技术(NRI路由机制和负荷分担),重点讨论了核心网D接口信令的流量,根据MSC Pool的技术特点,提出了组网规划的前提条件和规划时需要注意的问题,最后总结了MSC Pool技术的特点,在结论部分给出了MSC Pool可能存在的安全隐患。  相似文献   
63.
Nucleate pool boiling experiments with constant wall temperature were performed using pure R113 for subcooled, saturated, and superheated pool conditions. A microscale heater array and Wheatstone bridge circuits were used to maintain the constant wall temperature and to measure the instantaneous heat flow rate accurately with high temporal and spatial resolutions. Images of bubble growth were taken at 5000 frames per second using a high-speed CCD camera synchronized with the heat flow rate measurements. The bubble geometry was obtained from the captured bubble images. The effect of the pool conditions on the bubble growth behavior was analyzed using dimensionless parameters for the initial and thermal growth regions. The effect of the pool conditions on the heat flow rate behavior was also examined. The bubble growth behaviors during subcooled, saturated, and superheated pool boiling were analyzed using a modified Jakob number that we newly defined. Dimensionless time and bubble radius parameters with the modified Jakob number characterized the bubble growth behavior well. These phenomena require further analysis for various pool temperature conditions, and this study will provide good experimental data with precise constant wall temperature boundary condition for such works.  相似文献   
64.
    
We consider a relatively simple model for pool boiling processes. This model involves only the temperature distribution within the heater and describes the heat exchange with the boiling fluid via a nonlinear boundary condition imposed on the fluid–heater interface. This results in a standard heat equation with a nonlinear Neumann boundary condition on part of the boundary. In this paper, we analyse the qualitative structure of steady-state solutions of this heat equation. It turns out that the model allows both multiple homogeneous and multiple heterogeneous solutions in certain regimes of the parameter space. The latter solutions originate from bifurcations on a certain branch of homogeneous solutions. We present a bifurcation analysis that reveals the multiple-solution structure in this mathematical model. In the numerical analysis a continuation algorithm is combined with the method of separation-of-variables and a Fourier collocation technique. For both the continuous and discrete problem a fundamental symmetry property is derived that implies multiplicity of heterogeneous solutions. Numerical simulations of this model problem predict phenomena that are consistent with laboratory observations for pool boiling processes.  相似文献   
65.
本文针对MSC Pool技术在河南移动实际组网中和容灾场景中遇到的自动容灾和被叫恢复问题,进行了深入的分析并提出了有效的解决方案,将3GPP协议中的VLR Restore流程引入到MSC Pool容灾场景,利用SCCP层备份寻址实现HLR路由数据的自动倒换。多次模拟实验证明,该方案能够自动,零时间内实现核心网网元级设备容灾场景下的一次被叫恢复难题。并且,本方案属于零投资、采用开放的协议和规范、不局限设备厂家和软件版本,为MSC Pool技术在河南移动的大规模应用铺平了道路,确保了区域经济的平稳、健康发展。  相似文献   
66.
随着我国4G牌照的发放,中国移动开始大规模部署TD-LTE网络,采取了LTE EPC集中部署、PTN回传等组网方案及技术。本文从LTE回传现状出发,重点讨论EPC组Pool的传送方案,并结合规划实例进行说明,提出L3 PTN带宽规划和设备选型的相关建议,为EPC组Pool传送网建设提供参考。  相似文献   
67.
68.
材料在辐照过程中所受的中子注量是辐照性能研究中的一个重要参数。上联箱铝材作为300#研究堆关键结构材料,经历了从反应堆首次临界到退役的全过程,极具材料辐照效应研究价值。为获取整个反应堆运行寿期内的上联箱中子注量水平,须克服堆芯装载变化频繁与堆芯不断扩大装载两大关键难点,故提出了堆芯归并等效计算方法。通过该方法的成功应用,得到了300#研究堆寿期内上联箱铝材的中子注量,并进行了误差分析。  相似文献   
69.
实验测量了二元混合工质HFC23/CFC13池核沸腾传热特性。加热面为紫铜表面,实验测量的压力范围为0.1~0.55 MPa,热流范围为10 kW/m2~300 kW/m2。实验数据同现有经验关联式的计算结果相比较,发现Fu jita andTsutsu i关联式和Thom e and Shak ir关联式对混合工质HFC23/CFC13的传热系数预测较准确,预测值与实验值之差≤±20%。  相似文献   
70.
The ability to accurately characterize an underwater sound source is an important prerequisite for many applications including detection, classification, monitoring and mitigation. Unfortunately, anechoic underwater recording environments required to make ideal recordings are generally not available. This paper presents a practical approach to source characterization when working in an imperfect recording environment; the source spectrum is obtained by equalizing the recording with the inverse of the channel’s impulse response (IR). An experiment was conducted in a diving well (depth of 5.18 m) using a logarithmic chirp to obtain the IR. IR length is estimated using methods borrowed from room acoustics and inversion of non-minimum phase IR is accomplished separately in the time and frequency domain to allow for a direct comparison. Results indicate that the energy of controlled sources can be recovered with root-mean-square error of −70 dB (10–70 kHz band). Two equations, one coherent and the other incoherent, are presented to calculate source spectral levels of an unknown source in a reverberant environment. This paper introduces a practical procedure outlining steps to obtain an anechoic estimate of an unknown source using equipment generally available in an acoustic laboratory.  相似文献   
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