基于CMN和PMC算法的语音增强失真补偿方法研究

语音增强技术在低信噪比情况下,由于语音增强带来的失真使得系统的识别性能严重下降.因此提出一种结合特征空间的倒谱均值归一化算法(CMN)和模型空间的并行模型合并算法(PMC)的语音增强失真补偿技术.实验结果表明,该方法有效提高了低信噪比情况下的语音信号识别率.     

移动核心网电路域的VoIP演进

运营商传统电路交换网络发展遇到瓶颈,IP承载网技术发展更加成熟,移动核心网电路域的VoIP演进正逐步推进。文章对核心网VoIP演进带来的变化及承载网、核心设备如何保障语音业务质量、安全等进行了探讨。     

正激式变换器输入端共模噪声的研究

噪声源的研究对噪声控制是十分重要的，掌握噪声特征是噪声控制方法比较以及滤波器设计的基础，本文以电路理论为基础，建立了单端正激式变换器由功率MOSFET的漏极与接地散热器之间寄生电容所引起的输入端共模噪声分析模型，借助于PSPICE仿真工具，分析了硬开关和软开关情况下所产生的共模噪声，本文的工作将有助于开关电源电磁干扰诊断和滤波器的设计。     

Enhanced Common‐Mode Noise Rejection Method Based on Impedance Mismatching Compensation for Wireless Capsule Endoscopy Systems

Common‐mode noise (CMN) is an unresolved problem in wireless capsule endoscopy (WCE) systems. In a WCE system, CMN originates from various electric currents found within the human body or external interference sources and causes critical demodulation performance degradation. The differential operation, a typical method for the removal of CMN rejection, can remove CMN by subtracting two signals simultaneously received by two reception sensors attached to a human body. However, when there is impedance mismatching between the two reception sensors, the differential operation method cannot completely remove CMN. Therefore, to overcome this problem, we propose an enhanced CMN rejection method. The proposed method performs not only subtraction but also addition between two received signals. Then a CMN ratio can be estimated by sufficient accumulation of division operation outcomes between the subtraction and addition outputs during the guard period. Finally, we can reject the residual CMN by combining the subtraction and addition outputs.     

利用Java实现基于CORBA的计算机网络管理

在介绍ＣＯＲＢＡ和计算机网管的基本原理的基础上,分析如何在计算机网管系统中引入ＣＯＲＢＡ技术,以适应日趋分布的计算机网络。该文提出了四种实现方式,详细分析了后两种,并对它们进行了比较。     

一种基于CMN的跨域承载互通的方法

现有的CMN组网方案只适用于BICC,可以看作剔除了BCF功能的MSC Server,CMN可以由任何一台MSC Server改造而来,而在MGCF中,尚未不具备跨SIP与BICC的CMN,因此势必会在媒体流上占用多余的承载以实现信令交互、承载建立、形成通话,无法实现现网网络的扁平化发展。基于此,提出一种方法,在MGCF中对BICC与SIP协议转换时,利用两端设备采用了相同的编解码,使媒体流消息在MGCF上进行透传,将多占用的承载资源释放出来,完成网络扁平化、维护清晰化。     

Ecosystem-inspired enterprise modelling framework for collaborative and networked manufacturing systems

Rapid changes in the open manufacturing environment are imminent due to the increase of customer demand, global competition, and digital fusion. This has exponentially increased both complexity and uncertainty in the manufacturing landscape, creating serious challenges for competitive enterprises. For enterprises to remain competitive, analysing manufacturing activities and designing systems to address emergent needs, in a timely and efficient manner, is understood to be crucial. However, existing analysis and design approaches adopt a narrow diagnostic focus on either managerial or engineering aspects and neglect to consider the holistic complex behaviour of enterprises in a collaborative manufacturing network (CMN). It has been suggested that reflecting upon ecosystem theory may bring a better understanding of how to analyse the CMN. The research presented in this paper draws on a theoretical discussion with aim to demonstrate a facilitating approach to those analysis and design tasks. This approach was later operationalised using enterprise modelling (EM) techniques in a novel, developed framework that enhanced systematic analysis, design, and business-IT alignment. It is expected that this research view is opening a new field of investigation.     

Achieving yield confidence in a flow shop with single rework station via capacity expansion and process improvement

This paper provides an improvement strategy for a flow shop with single rework station by modeling the flow shop as a capacitated manufacturing network (CMN) to achieve the required yield confidence utilizing a confidence-based analysis. We define the yield confidence as a performance indicator to evaluate the probability that a specified level of demand will be satisfied. Specifically, this paper considers capacity expansion and process improvement issues. First, a model is proposed to represent the CMN and to characterize the probability that a unit of material is successfully transformed into a final product. This model further identifies the required amount of (ideal) input to satisfy the customer demand and to achieve the desired yield confidence. In particular, this ideal input can be seen as the least wasteful input for the CMN. Capacity expansion and process improvement are considered when the current capacity of the CMN is insufficient to process the ideal input. The approach identifies the target output ratios of stations needed to achieve a process improvement goal. Two benchmark examples are provided to demonstrate the model building, capacity expansion, and process improvement steps.     

移动核心网电路域的VoIP演进

运营商传统电路交换网络发展遇到瓶颈,IP承载网技术发展更加成熟,移动核心网电路域的VoIP演进正逐步推进。文章对核心网VoIP演进带来的变化及承载网、核心设备如何保障语音业务质量、安全等进行了探讨。