Deployment Strategy for Multiple Controllers Based on the Aviation On-Board Software-Defined Data Link Network

In light of the escalating demand and intricacy of services in contemporary terrestrial,maritime,and aerial combat operations,there is a compelling need for enhanced service quality and efficiency in airborne cluster communication networks.Software-Defined Networking(SDN)proffers a viable solution for the multifaceted task of cooperative communication transmission and management across different operational domains within complex combat contexts,due to its intrinsic ability to flexibly allocate and centrally administer network resources.This study pivots around the optimization of SDN controller deployment within airborne data link clusters.A collaborative multi-controller architecture predicated on airborne data link clusters is thus proposed.Within this architectural framework,the controller deployment issue is reframed as a two-fold problem:subdomain partition-ing and central interaction node selection.We advocate a subdomain segmentation approach grounded in node value ranking(NDVR)and a central interaction node selection methodology predicated on an enhanced Artificial Fish Swarm Algorithm(AFSA).The advanced NDVR-AFSA(Node value ranking-Improved artificial fish swarm algorithm)algorithm makes use of a chaos algorithm for population initialization,boosting population diversity and circumventing premature algorithm convergence.By the integration of adaptive strategies and incorporation of the genetic algorithm’s crossover and mutation operations,the algorithm’s search range adaptability is enhanced,thereby increasing the possibility of obtaining globally optimal solutions,while concurrently augmenting cluster reliability.The simulation results verify the advantages of the NDVR-IAFSA algorithm,achieve a better load balancing effect,improve the reliability of aviation data link cluster,and significantly reduce the average propagation delay and disconnection rate,respectively,by 12.8%and 11.7%.This shows that the optimization scheme has important significance in practical application,and can meet the high requirements of modern sea,land,and air operations to aviation airborne communication networks.

Studies on Novel Anti-jamming Technique of Unmanned Aerial Vehicle Data Link

Based on the M-ary spread spectrum （M-ary-SS）, direct sequence spread spectrum （DS-SS）, and orthogonal frequency division multiplex （OFDM）, a novel anti-jamming scheme, named orthogonal code time division multi-subchannels spread spectrum modulation （OC-TDMSCSSM）, is proposed to enhance the anti-jamming ability of the unmanned aerial vehicle （UAV） data link. The anti-jamming system with its mathematical model is presented first, and then the signal formats of transmitter and receiver are derived. The receiver＇s bit error rate （BER） is demonstrated and anti-jamming performance analysis is carded out in an additive white Ganssian noise （AWGN） channel. Theoretical research and simulation results show the anti-jamming performance of the proposed scheme better than that of the hybrid direct sequence frequency hopping spread spectrum （DS/FH SS） system. The jamming margin of the OC-TDMSCSSM system is 5 dB higher than that of DS/FH SS system under the condition of Rician channel and full-band jamming, and 6 dB higher under the condition of Rician channel environment and partial-band jamming.

Simulation of Dynamic Electromagnetic Interference Environment for Unmanned Aerial Vehicle Data Link

In order to test the anti-interference ability of an Unmanned Aerial Vehicle(UAV) data link in a complex electromagnetic environment,a method for simulating the dynamic electromagnetic interference of an indoor wireless environment is proposed.This method can estimate the relational degree between the actual face of an UAV data link in an interface environment and the simulation scenarios in an anechoic chamber by using the Grey Relational Analysis(GRA) theory.The dynamic drive of the microwave instrument produces a real-time corresponding interference signal and realises scene mapping.The experimental results show that the maximal correlation between the interference signal in the real scene and the angular domain of the radiation antenna in the anechoic chamber is 0.959 3.Further,the relational degree of the Signal-toInterference Ratio(SIR) of the UAV at its reception terminal indoors and in the anechoic chamber is 0.996 8,and the time of instrument drive is only approximately 10 μs.All of the above illustrates that this method can achieve a simulation close to a real field dynamic electromagnetic interference signal of an indoor UAV data link.

Blockchain-based data transmission control for Tactical Data Link

Tactical Data Link(TDL)is a communication system that utilizes a particular message format and a protocol to transmit data via wireless channels in an instant,automatic,and secure way.So far,TDL has shown its excellence in military applications.Current TDL adopts a distributed architecture to enhance anti-destruction capacity.However,It still faces a problem of data inconsistency and thus cannot well support cooperation across multiple militarily domains.To tackle this problem,we propose to leverage blockchain to build an automatic and adaptive data transmission control scheme for TDL.It achieves automatic data transmission and realizes information consistency among different TDL entities.Besides,applying smart contracts based on blockchain further enables adjusting data transmission policies automatically.Security analysis and experimental results based on simulations illustrate the effectiveness and efficiency of our proposed scheme.

A Mathematical Solution to String Matching for Big Data Linking

This paper describes how data records can be matched across large datasets using a technique called the Identity Correlation Approach （ICA）. The ICA technique is then compared with a string matching exercise. Both the string matching exercise and the ICA technique were employed for a big data project carried out by the CSO. The project was called the SESADP （Structure of Earnings Survey Administrative Data Project） and involved linking the Irish Census dataset 2011 to a large Public Sector Dataset. The ICA technique provides a mathematical tool to link the datasets and the matching rate for an exact match can be calculated before the matching process begins. Based on the number of variables and the size of the population, the matching rate is calculated in the ICA approach from the MRUI （Matching Rate for Unique Identifier） formula, and false positives are eliminated. No string matching is used in the ICA, therefore names are not required on the dataset, making the data more secure ＆ ensuring confidentiality. The SESADP Project was highly successful using the ICA technique. A comparison of the results using a string matching exercise for the SESADP and the ICA are discussed here.

Privacy Protection for Big Data Linking using the Identity Correlation Approach

Privacy protection for big data linking is discussed here in relation to the Central Statistics Office （CSO）, Ireland＇s, big data linking project titled the ＇Structure of Earnings Survey - Administrative Data Project＇ （SESADP）. The result of the project was the creation of datasets and statistical outputs for the years 2011 to 2014 to meet Eurostat＇s annual earnings statistics requirements and the Structure of Earnings Survey （SES） Regulation. Record linking across the Census and various public sector datasets enabled the necessary information to be acquired to meet the Eurostat earnings requirements. However, the risk of statistical disclosure （i.e. identifying an individual on the dataset） is high unless privacy and confidentiality safe-guards are built into the data matching process. This paper looks at the three methods of linking records on big datasets employed on the SESADP, and how to anonymise the data to protect the identity of the individuals, where potentially disclosive variables exist.

NEW DYNAMIC SLOT ASSIGNMENT SCHEME OF SELF-ORGANIZED TDMA VHF DATA LINK

According to the analysis of the very high frequency (VHF) self organized time division multiple access (S TDMA) aviation data link, a new dynamic slot assignment scheme is proposed in this paper, which adopts variable data frame structure and can eliminate the effect of the idle slot on message delay. By using queue theory, the analysis models of the new scheme and previous scheme are presented, and the performance of message delay and that of system throughput are analyzed under two schemes. The simulation results show that the new scheme has a better performance than the previous one in the message delay and system throughput.

System Design Of Security Evaluation For Data Link Communications

Data link communication requires data communication process must have reliability, availability, confidentiality, availability, integrity, non-repudiation, controllability.This has a great effect to ensure the normal communication functions.In this paper the author on the basis of many years of work experience, first discussed the establishment of a risk assessment system data link,then focused on the problem of index weight assessment.To data communication security, this research article will provide some references.

Application of Adaptive Coded Modulation Technology in UAV Data Link

UAV data link has been considered as an important part of UAV communication system, through which the UAV could communicate with warships. However, constant coding and modulation scheme that UAV adopts does not make full use of the channel capacity when UAV communicates with warships in a good channel environment. In order to improve channel capacity and spectral efficiency, adaptive coded modulation technology is studied. Based on maritime channel model, SNR estimation technology and adaptive threshold determination technology, the simulation of UAV data link communication is carried out in this paper. Theoretic analysis and simulation results show that according to changes in maritime channel state, UAV can dynamically adjust the adaptive coded modulation scheme on the condition of meeting target Bit-Error-Rate (BER), the maximum amount of data transfer is non-adaptive systems three times.

Modeling and Simulation Study of Space Data Link Protocol

This research paper describes the design and implementation of the Consultative Committee for Space Data Systems (CCSDS) standards REF _Ref401069962 \r \h \* MERGEFORMAT [1] for Space Data Link Layer Protocol (SDLP). The primer focus is the telecommand (TC) part of the standard. The implementation of the standard was in the form of DLL functions using C++ programming language. The second objective of this paper was to use the DLL functions with OMNeT++ simulating environment to create a simulator in order to analyze the mean end-to-end Packet Delay, maximum achievable application layer throughput for a given fixed link capacity and normalized protocol overhead, defined as the total number of bytes transmitted on the link in a given period of time (e.g. per second) divided by the number of bytes of application data received at the application layer model data sink. In addition, the DLL was also integrated with Ground Support Equipment Operating System (GSEOS), a software system for space instruments and small spacecrafts especially suited for low budget missions. The SDLP is designed for rapid test system design and high flexibility for changing telemetry and command requirements. GSEOS can be seamlessly moved from EM/FM development (bench testing) to flight operations. It features the Python programming language as a configuration/scripting tool and can easily be extended to accommodate custom hardware interfaces. This paper also shows the results of the simulations and its analysis.

面向Link16的QualNet与虚拟机信息交互接口设计与实现

Link16是美国国防部采用的高速视距战术数据链,广泛应用于美国海军、联合部队和北约部队,针对其开展测试评估具有重要军事意义。通过硬件在环技术将Link16实物设备接入到仿真测试中,可有效提高测试结果的真实性和准确性。然而当测试场景需要进行实物设备组网测试时,仍会带来成本问题。为此,提出一种面向QualNet MAC层的Link16专属模型以及与之匹配的虚拟机信息交互接口。该模型可高逼真模拟Link16通信行为,实现Link16节点竞争接入、时隙划分、NPG分组等功能。并基于数据分布式服务实现了虚拟机交互接口,将运行在虚拟机的Link16设备模型接入QualNet测试场景。实验测试结果表明,所设计模型具有较高真实性和准确性且接口引入延时不超过1 ms,为大规模数据链网络测试提供一种新方法。

基于NC-Link的静压转台数据集控平台应用研究

以提升重型机床回转类静压导轨的高速性能和智能化水平为目标,设计了一套基于NC-Link协议和开源项目Thingsboard的静压转台数据集控和可视化应用框架。实现了静压油膜厚度的在线检测和自动调整,静压导轨载荷的自动识别,以及静压工作状态的云监控。

基于BIM和Linked Data的建筑业电子商务信息融合框架

建筑业电子商务平台信息存在海量、异构和分散等问题,影响了建筑业电子商务的发展。在分析现有电子商务平台信息特征,以及研究BIM和Linked Data技术在信息集成方面应用的基础上,提出一种基于BIM和Linked Data的建筑业电子商务信息融合框架。该框架以BIM作为商品信息模型;使用Linked Data将供应商信息、客户信息、配送信息、交易信息、采购合同信息关联到商品信息BIM模型中,形成融合的信息环境,为实现建筑业电子商务信息融合提供了一种有效的解决思路。

多音干扰下Nakagami-m信道传输Link16数据链的性能分析

Link16数据链的应用综合广泛,由于运用了跳扩频和编码技术使其具有强大的抗干扰能力。为了探究Link16数据链在衰落信道下的响应,在加性高斯白噪信道的基础之上,研究了Link16数据链经过Nakagami-m衰落信道的系统性能。着重推导了Link16数据链单脉冲结构在多音干扰下经过Nakagami-m衰落信道的误码率(bit error rate,BER)表达式,并给出了双脉冲结构BER公式。仿真实验结果验证了Link16数据链单脉冲结构在多音干扰下经过Nakagami-m衰落信道的BER公式的准确性,分析了多径参数对Link16数据链抗干扰性能的影响,得出增加衰落参数m和可分辨路径可以提升Link16数据链的系统性能,且当信干比一定、被干扰频点个数在25个及以上时系统BER达到10-1。

低信噪比场景下Link-16系统的联合频偏估计算法

对于Link-16数据链终端平台在低信噪比(SNR)高动态场景下的多普勒频率偏移问题,该文设计一种新的数据结构,推导了该结构下的克拉默-拉奥下界(CRLB),并在此基础上提出一种联合频域变换与时域自相关运算的分步式频偏估计算法。其基本思想是,首先对接收信号做自相关处理,然后通过频域变换进行最大值索引,结合修正因子得到多普勒频移的粗估计值,再利用时域的改进L&R算法对接收信号进行细估计,根据两步估计算法得到最终的频偏估计值。算法应用蒙特卡罗实验仿真,仿真结果表明,与传统频偏估计算法相比,该算法的归一化均方误差更接近CRLB,在多普勒频偏为[–20 kHz,20 kHz]时,估计精度可达10^(–5)。在低信噪比环境下,所提算法能达到较为理想的估计效果,适用于Link-16数据链通信。

基于Linked Data技术的公安监控系统技术研究

信息化对传统的公安系统情报系统提出了前所未有的挑战,公安系统信息化是公安情报系统升级改造的重要工作。警用语义网情报系统对公安的情报信息的提取和共享等方面有很好的支持。运用基于Linked Data技术的语义网,对公安的重点人员监控系统进行研究分析,提出监控系统的工作流程。

基于Open Linked Data的中西医关联发现云平台

提出了一个用于中西医关联发现的云平台—BioTCM Cloud。该平台是构建在大量的开放链接数据(Linked Data)的基础上,以及跨领域知识整合的需要。面对海量的链接数据,提出了基于MapReduce框架的分布式语义推理框架,用于解决基于领域规则的知识推理问题。以中医草药为案例,分布式语义推埋可以建立中医药和西医之间的关联,以促进中西医之间的沟通和数据共享。

Linked Data数据集的主题模型建立方法

提出了建立Linked Data数据集主题模型的方法.首先,将数据集中的RDF陈述三元组转换成主谓宾结构的语句,从而将Linked Data数据集转化为文本文档;然后,使用LDA算法对所有数据集的文本文档进行主题建模,即可得到每个数据集的主题向量,该向量就是描述数据集内容主题的特征.在Linked Data数据集链接目标推荐问题上,引入数据集的主题特征进行实验.使用数据集主题向量的余弦相似度替换基于记忆的协同过滤推荐算法中的相似度计算模块.结果表明,推荐效果比原始的协同过滤算法有很大提升.

开放关联数据赋能书目数据的实践指南--评Linked Open Data Enabled Bibliographical Data(LODE-BD)3.0

[目的/意义]评价Linked Open Data Enabled Bibliographical Data(LODE-BD)3.0一书在开放关联数据赋能书目数据方面做出的学术贡献,帮助读者掌握开放关联数据的应用技能。[方法/过程]阐述开放关联数据应用指南的编撰目的,理解LODE-BD的实践建议,思考如何将书目数据表示为开放关联数据,帮助用户开放获取相关的书目资源,实现书目资源的互联互通。[结果/结论]该书是一本成熟的,关于如何选择合适编码策略来生成开放关联数据赋能的书目数据的操作指南,具有丰富的理论价值、方法指导与实践意义。

BioPW+:基于Linked Data的生物途径数据可视化系统

自Linked Data项目被提出以来,大量的开放关联数据被发布到语义Web上,这其中就包含了许多的生物途径数据集。为了使生物学家能够有效地利用这些开放的数据集,对基于Linked Data的生物途径数据可视化系统进行研究,提出了生物途径可视化模型和展示布局方案,并且采用标识符动态映射实现了多源生物途径数据的浏览,最终开发了基于Linked Data的生物途径数据查询可视化系统——BioPW+。该系统应用语义Web技术,依靠SPARQL查询来定位生物途径的基本信息,然后基于Open PHACTS平台获取生物途径元素的详细信息,最终Web界面采用力导向图布局、Sankey图布局对生物途径数据进行展示并提供多种交互操作。与已有的仅仅基于某一特定数据库的生物途径工具相比,BioPW+系统基于Linked Data,可以同时一次性展示多个数据集中的生物途径数据及与其相关的其他生物化学数据,极大节省了时间并增强了数据的完整性。