Exponential flux-controlled memristor model and its floating emulator

As commercial memristors are still unavailable in the market, mathematic models and emulators which can imitate the features of the mernristor are meaningful for further research. In this paper, based on the analyses of characteristics of the q-φ curve, an exponential flux-controlled model, which has the quality that its memductance （memristance） will keep monotonically increasing or decreasing unless the voltage＇s polarity reverses （if not approach the boundaries）, is constructed. A new approach to designing the floating emulator of the memristor is also proposed. This floating structure can flexibly meet various demands for the current through the memristor （especially the demand for a larger current）. The simulations and experiments are presented to confirm the effectiveness of this model and its floating emulator.

Effective Capacity in Cognitive Radio Networks with Relay and Primary User Emulator

In this paper,the transmission performances are studied in cognitive radio networks with primary user emulator and relay existence.In the proposed network,the users include primary users,secondary users and primary user emulators.The decreasing access priority of the users are primary users,primary user emulators and secondary users.Different user access to the network results in different transmission effects.We impose interference power constraints on the secondary users to protect the primary users from being interfered.We also adopt the transmission mechanism that transits among more than one secondary transmitters,secondary receivers and relays.The transition models of the transmission states are proposed to describe the transmission mechanism.To investigate the transmission performances,the theory of effective capacity is adopted.The transmission performances in terms of effective capacity are expressed and demonstrated under different transmission policies.The overall effective capacity,as the overall data traffic in the cognitive radio network,is calculated.Besides,the overall effective capacity is demonstrated under different transmission strategies.The results show the greedy transmission strategy outperforms the rest of the transmission 8 policies in the overall effective capacity.For a larger number of the users,the effective capacity converges to a certain value.

Research on numerical emulator of mine methane and coal dust explosion

The mathematical physics model of mine methane and coal dust explosion propagation was established in the research,by using continuous phase,combustion,par- ticulate equations of mathematical physics.Based upon the data from mine methane drainage roadway explosion,and mine methane and coal dust explosion propagation ex- perimental studies,the numerical emulator system of mine methane and coal dust explo- sion software was developed by using prevalent flow simulation platform,which can be used to simulate the explosion accidents process effectively.In addition,the system can also be used to determine whether coal dust involved in the explosion,and to simulate accurately the transition from deflagration to detonation in methane explosion,propagation velocity of explosion shock,attenuation pattern,and affected area of explosion.

Inverter-Based Diesel Generator Emulator for the Study of Frequency Variations in a Laboratory-Scale Autonomous Power System

This paper presents the modeling, simulation and practical implementation of an inverter-based diesel generator emulator. The main purpose of this emulator is for the study of frequency variations in diesel-based autonomous power systems in a laboratory environment where the operation of a real diesel generator is not possible. The emulator basically consists in a voltage source inverter with a second order output filter which voltage references are given by the model of the diesel generator. The control of the emulator is based on the digital signal processor TMS320F2812, where the mathematical models of the diesel generator and the control of the inverter are computed in real-time. Parameters for the model were obtained from commercially available components. Experimental results for different values of speed droop showed that the emulator achieves a satisfactory performance in the transient and stationary response. For the stationary response, the measured frequency deviates from theoretical values with a mean absolute error of: 0.06 Hz for 0% droop, 0.037 Hz for 3% droop, and 0.087 Hz for 5% droop. For the transient response, the measured frequency nadir deviates from simulations in: 0.05 Hz for 0% droop, 0.02 Hz for 3% droop, and 0.1 Hz for 5% droop.

Assessment of Quality of Experience (QoE) of Web and Video Services over a Mobile Network Using a Network Emulator

This paper investigates the subjective assessment of QoE of web and video services over a mobile network. To achieve this, the authors used the network emulator (NetEm) traffic control functionality to simulate the dynamic behaviour of a mobile network. Experiments were conducted in a laboratory setting and test conditions were varied to ascertain the QoE, with a focus on QoE metrics such as delay and packet loss ratio. From the experiments conducted, it was observed that there was a negative correlation between delay and average mean opinion score (MOS), and between packet loss ratio and average MOS. The results obtained can be adopted by network operators to provide better services which would lead to improved subscriber base and profitability for the operators and better QoE for the end users.

Suppression of ferroresonance using passive memristor emulator

Power system inherently consists of capacitance and inductance in its components. Equipment with saturable inductance and circuit capacitance provides circumstances of generating ferroresonance, resulting in overvoltage and overcurrent in the connected system. The effects of ferroresonance result in insulation failure and hence damage to the equipment is unavoidable. Though many devices are proposed for mitigating such circumstances, a promising technology of using memristors may provide better performance than others in the future. A memristor emulator using the N-channel JFET J310 is used in this work. Unlike other electronic components that replicate memristor properties, the chosen memristor emulator is a passive device since it does not need any external power supply. Simulation and experimental results verify the design of a memristor emulator and the characteristics of an ideal memristor. Experimental results prove that the memristor emulator can suppress the fundamental ferroresonance induced in a prototype single phase transformer. The results of the harmonic analysis also validate the memristor performance against the conventional technique.

OpenEmulator:一种面向TSN芯片验证的联合仿真平台

硬件仿真器是加快时间敏感网络TSN芯片验证的重要手段。由于TSN芯片复杂性远低于SoC芯片,基于CPU的硬件仿真器可满足TSN芯片验证的需求。为满足TSN芯片设计需求,设计实现了一个面向TSN芯片验证的硬件仿真器OpenEmulator。针对TSN系统仿真的特点,提出了一种应用于OpenEmulator的时间同步互锁机制,实现了运行芯片HDL设计代码的硬件仿真域与运行真实TSN软件的物理域之间的精确时间同步。OpenEmulator已经在OpenTSN芯片设计中得到应用,基于普通PC机,可在20 min内仿真包含6个节点的TSN网络初始化和首次时间同步功能,大大提升了TSN芯片仿真验证的效率。目前OpenEmulator已经开源并集成到最新发布的OpenTSN开源项目3.4版本中。

A Massively Parallel Re-Configurable Mesh Computer Emulator: Design, Modeling and Realization

Emulating massively parallel computer architectures represents a very important tool for the parallel programmers. It allows them to implement and validate their algorithms. Due to the high cost of the massively parallel real machines, they remain unavailable and not popular in the parallel computing community. The goal of this paper is to present an elaborated emulator of a 2-D massively parallel re-configurable mesh computer of size n x n processing elements (PE). Basing on the object modeling method, we develop a hard kernel of a parallel virtual machine in which we translate all the physical properties of its different components. A parallel programming language and its compiler are also devel-oped to edit, compile and run programs. The developed emulator is a multi platform system. It can be installed in any sequential computer whatever may be its operating system and its processing unit technology (CPU). The size n x n of this virtual re-configurable mesh is not limited;it depends just on the performance of the sequential machine supporting the emulator.

Development of an Emulator for the Plasma Process Control

This work aims at developing an automatic system for the control of the APS （air plasma spraying） plasma process in which some instability phenomena are present. APS is a versatile technique to produce coatings of powder material at high deposition rates. Using this technique, powder particles are injected into a plasma jet, where they are melted and accelerated towards a substrate. The coating microstructures and properties depend strongly on the characteristics of the plasma jet, which can be controlled by the adjustment of the process parameters. However, the imeractions among the spray variables, render optimization and control of this process are quite complex. Understanding relationships between coating properties and process parameters is mandatory to optimize the process technique and the product quality. We are interested in this work to build an on-line control model for the APS process based on the elements of artificial intelligence and to build an emulator that replicates the dynamic behavior of the process as closely as possible.

Research on the Model Emulator and Experiment Checkout of the Fuel Cell

In this paper a fuel cell emulator model suitable for each fuel cell type and power level is proposed. A power interface to the electronic load and a digital section are provided. The fuel cell steady-state, dynamic and thermal behaviour is modeled by the digital controller. The emulator architecture is deeply analyzed and remarks on hardware implementation algorithms are provided for further applications. The system is tested on a 10 W Proton Exchange Membrane （PEM） fuel cell and the high accuracy of the proposed emulator is shown by the comparison between experimental and simulation results.

Magnetic Field Emulations of Small Inhibitor RNA: Effects on Implanted GL261 Tumors in C57BL/6 Immune Competent Mice

EMulate Therapeutics has developed a system for emulating the effects of solvated molecules via their magnetic field recordings. Recordings of magnetic field emissions of select small inhibitor RNAs (siRNAs;murine targeting CTLA-4 and murine targeting PD-1) were tested on C57Bl/6 mice implanted subcutaneously with the GL261 murine tumor cell line. A signal composed of concatenated recordings of siRNA molecules targeting the murine CTLA-4 and PD-1 receptors (labeled A2) was used in immune competent C57Bl/6 mice. The mice were flank implanted with the murine glioblastoma cell line GL261. Mice were exposed to the signal continuously (24 hours a day) until tumor volumes reached the designated volume limit. Tumors were excised and analyzed via PAGE/Western blot for the expression of CTLA-4, PD-1, Ki67, Caspase 3, CD4 and CD8. Terminal blood draws were used for CBCs. We report the down regulation of the checkpoint inhibitors CTLA-4 in the exposed mice. Significant tumor volume reduction was observed in mice exposed to the siRNA signal compared to control mice;no adverse events were recorded. Cell blood counts (CBC) and protein expression patterns were observed to correlate with the expected function of protein expression inhibition of the targets.

eMule系统的协议分析

eMule是建立在点对点(peer to peer)技术上,以eDonkey协议为基础的文件共享软件。eMule的集中程度是混合性的,并非是完全无中心服务器。文章从协议的角度论述了eMule是如何实现文件共享,分析了客户端到服务器端、客户端到客户端之间的TCP通讯、UDP通讯的原理及相关的信息序列图。

eMule协议的安全性研究

研究eMule协议在安全性设计方面所存在的缺陷和不足,指出eMule软件在用户隐私泄露、用户积分欺诈和恶意代码攻击3个方面对用户造成的风险,给出改进方案。针对eMule协议在Ed2k链接格式上的2个漏洞提出一种新的攻击方式,设计攻击流程,并进行模拟攻击实验,实验结果表明该攻击方式的成功率达到100%。

基于P2P思想改进Emule技术实现视频点播的技术研究

分析了使用Emule实现视频点播系统的可行性。提出了在利用原有的Emule技术基础上,通过改进几个适合VOD系统的方法,尤其对关键的片段选择法进行了详细阐述,使流媒体文件未下载完就可以播放,设计上不改动Emule协议,可以兼容现有的Emule环境,从而以较小的代价实现视频点播功能。

eMule网络最佳节点标识

eMule网络是近年来越来越流行的文件共享对等网络.一直以来,文件源的准确定位是文件共享对等网络的一个关键步骤;此外,不健康内容的肆意传播也使网络监管成为必需.这些都导致准确确定eMule网络中节点的需求,同时促使eMule网络最佳节点标识问题的提出.然而,eMule网络中广泛使用的节点标识Kad ID因可被eMule用户任意更改,存在Kad ID别名,即单个节点对应多个Kad ID的情况,以及Kad ID重复,即多个节点对应同一个Kad ID的情况,从而使用传统Kad ID很难准确确定节点.为解决这一问题,首先定义候选节点标识的稳定因子用以评价候选标识;然后设计并实现一个证明可收敛且时空复杂度不高的eMule网络节点信息采集器——Rainbow,以获得实际eMule网络中节点的多个候选标识之间的对应关系信息.实验结果表明,{userID}的稳定因子最大,是节点标识集合2{Kad ID,userID,IP}?{Φ}中的最佳节点标识;之后,为了量化Kad ID别名问题的程度,对{userID}与{Kad ID}的关系进行探讨;最后对最佳节点标识的应用有效性进行分析,说明采用{userID}作为节点标识能够更准确地确定节点.总之,所确定的最佳节点标识为eMule网络的研究奠定了基础,Rainbow也为真实eMule网络测量提供了良好的工具.

基于Emulate的锅炉负荷协调控制系统仿真实训

基于罗克韦尔RSLogix5000软件和RSLogix Emulate5000仿真控制器,实现了锅炉负荷协调控制系统组态,利用RSView32开发了监控界面,利用RSLinx软件实现了各部分的数据通信,完成了锅炉协调控制系统的仿真实训项目开发。通过实训项目开发流程,按照整体架构、控制系统设计与仿真和监控界面三大任务,培养高校工科学生的工程意识、工程素质和工程实践能力。

基于UART Emulation技术的MVB网卡设计与组网研究

提出一种MVB网卡设计方案,在主机与MVB控制器的架构上结合UART Emulation技术,较为完善地实现了MVB设备的过程数据、消息数据、用户编程等功能。利用所设计的网卡与其他MVB网络设备进行MVB组网研究,依据单调比率算法进行周期扫描表的设计,在所搭建的网络平台上进行基本的通信测试,验证了设计的正确性和可行性。该网卡尺寸符合标准3U大小,便于与其他网络设备集成于工控机箱之中。

基于Emulab的网络仿真实验平台研究

为了构建用于网络教学和科研的实验平台,提出了基于Emulab的仿真实验平台的构建方法,给出了构建实验平台的实施步骤。然后以UMIR路由系统为实例,给出了该系统实验平台的搭建、部署及其测试过程。结果表明,基于Emulab的实验平台构建是可行的,它可以用于网络系统有关的测试与验证工作,对于网络实验教学、功能演示、理论研究和实际应用都具有十分重要的意义。

eMule系统中的非均匀性分布

eMule是一款流行的P2P软件,它拥有大量的用户。通过eMule中的KAD覆盖网络开发了一个爬虫,抓取了eMule系统中的节点信息。发现eMule系统中资源分布得非常不均匀,如节点所处的地区分布不均匀,IP分布不均匀,文件的副本数分布不均匀,用户共享的文件数分布也不均匀。文件的副本数分布和用户共享的文件数分布基本符合Zipf分布,但是这两个分布并不完全符合Zipf,有着自己独特的特性。