在室内可见光通信中符号间干扰和噪声会严重影响系统性能,K均值(K-means)均衡方法可以抑制光无线信道的影响,但其复杂度较高,且在聚类边界处易出现误判。提出了改进聚类中心点的K-means(Improved Center K-means,IC-Kmeans)算法,通过随...在室内可见光通信中符号间干扰和噪声会严重影响系统性能,K均值(K-means)均衡方法可以抑制光无线信道的影响,但其复杂度较高,且在聚类边界处易出现误判。提出了改进聚类中心点的K-means(Improved Center K-means,IC-Kmeans)算法,通过随机生成足够长的训练序列,然后将训练序列每一簇的均值作为K-means聚类中心,避免了传统K-means反复迭代寻找聚类中心。进一步,提出了基于神经网络的IC-Kmeans(Neural Network Based IC-Kmeans,NNIC-Kmeans)算法,使用反向传播神经网络将接收端二维数据映射至三维空间,以增加不同簇之间混合数据的距离,提高了分类准确性。蒙特卡罗误码率仿真表明,IC-Kmeans均衡和传统K-means算法的误码率性能相当,但可以显著降低复杂度,特别是在信噪比较小时。同时,在室内多径信道模型下,与IC-Kmeans和传统Kmeans均衡相比,NNIC-Kmeans均衡的光正交频分复用系统误码率性能最好。展开更多
As an extension of the traditional encryption technology,information hiding has been increasingly used in the fields of communication and network media,and the covert communication technology has gradually developed.T...As an extension of the traditional encryption technology,information hiding has been increasingly used in the fields of communication and network media,and the covert communication technology has gradually developed.The blockchain technology that has emerged in recent years has the characteristics of decentralization and tamper resistance,which can effectively alleviate the disadvantages and problems of traditional covert communication.However,its combination with covert communication thus far has been mostly at the theoretical level.The BLOCCE method,as an early result of the combination of blockchain and covert communication technology,has the problems of low information embedding efficiency,the use of too many Bitcoin addresses,low communication efficiency,and high costs.The present research improved on this method,designed the V-BLOCCE which uses base58 to encrypt the plaintext and reuses the addresses generated by Vanitygen multiple times to embed information.This greatly improves the efficiency of information embedding and decreases the number of Bitcoin addresses used.Under the premise of ensuring the order,the Bitcoin transaction OP_RETURN field is used to store the information required to restore the plaintext and the transactions are issued at the same time to improve the information transmission efficiency.Thus,a more efficient and feasible method for the application of covert communication on the blockchain is proposed.In addition,this paper also provides a more feasible scheme and theoretical support for covert communication in blockchain.展开更多
The static and predictable characteristics of cyber systems give attackers an asymmetric advantage in gathering useful information and launching attacks.To reverse this asymmetric advantage,a new defense idea,called M...The static and predictable characteristics of cyber systems give attackers an asymmetric advantage in gathering useful information and launching attacks.To reverse this asymmetric advantage,a new defense idea,called Moving Target Defense(MTD),has been proposed to provide additional selectable measures to complement traditional defense.However,MTD is unable to defeat the sophisticated attacker with fingerprint tracking ability.To overcome this limitation,we go one step beyond and show that the combination of MTD and Deception-based Cyber Defense(DCD)can achieve higher performance than either of them.In particular,we first introduce and formalize a novel attacker model named Scan and Foothold Attack(SFA)based on cyber kill chain.Afterwards,we develop probabilistic models for SFA defenses to provide a deeper analysis of the theoretical effect under different defense strategies.These models quantify attack success probability and the probability that the attacker will be deceived under various conditions,such as the size of address space,and the number of hosts,attack analysis time.Finally,the experimental results show that the actual defense effect of each strategy almost perfectly follows its probabilistic model.Also,the defense strategy of combining address mutation and fingerprint camouflage can achieve a better defense effect than the single address mutation.展开更多
To ensure the extreme performances of the new 6G services,applications will be deployed at deep edge,resulting in a serious challenge of distributed application addressing.This paper traces back the latest development...To ensure the extreme performances of the new 6G services,applications will be deployed at deep edge,resulting in a serious challenge of distributed application addressing.This paper traces back the latest development of mobile network application addressing,analyzes two novel addressing methods in carrier network,and puts forward a 6G endogenous application addressing scheme by integrating some of their essence into the 6G network architecture,combining the new 6G capabilities of computing&network convergence,endogenous intelligence,and communication-sensing integration.This paper further illustrates how that the proposed method works in 6G networks and gives preliminary experimental verification.展开更多
This thesis aims at exploring meanings of different addresses and their correct and suitable translations in both Chinese and English. After the introduction to the definition and meaning of addresses, the whole thesi...This thesis aims at exploring meanings of different addresses and their correct and suitable translations in both Chinese and English. After the introduction to the definition and meaning of addresses, the whole thesis probes into this problem from two aspects: the reasons which lead to the differences in addresses among relatives in both Chinese and English, and the ways how to translate addresses properly according to the situations. With the exploration, the writer hopes to introduce the cultural differences from the perspective of translations of addresses.展开更多
The United Kingdom are still facing great challenges in all aspects after about half a year's struggle since they had made the decision to Brexit. The authorities are also trying to convince the public of its auth...The United Kingdom are still facing great challenges in all aspects after about half a year's struggle since they had made the decision to Brexit. The authorities are also trying to convince the public of its authorities by all means, especially by public speeches. This paper is going to analyze how the Queen and the Prime Minster try to convince their public of a better future in their New Year Addresses through the method of cluster analysis.展开更多
The article mainly studies the application strategy of automatic addressable single-lamp control technology in tunnel lighting.It encompasses an introduction to this technology,an analysis of the tunnel lighting syste...The article mainly studies the application strategy of automatic addressable single-lamp control technology in tunnel lighting.It encompasses an introduction to this technology,an analysis of the tunnel lighting system using automatic addressable single-lamp control technology,and outlines the main development direction for this technology in modern tunnel lighting.The aim is to offer insights that can inform the rational deployment of this technology,thereby enhancing the lighting control effectiveness in modern tunnels and meeting their specific lighting requirements more effectively.展开更多
Addresses are important data for urban applications. About 80% of the information local authorities use have a geographic component that is generally related to addresses. Addressing systems efficiency depend on the q...Addresses are important data for urban applications. About 80% of the information local authorities use have a geographic component that is generally related to addresses. Addressing systems efficiency depend on the quality of addresses locators. There are several methods to collect data. Surveys from the field are essential: GPS and pre-printed maps can be used to achieve this goal. GPS surveys from the field may be a solution, but it remains practical only for limited areas. To insure an accepted accuracy, GPS methods need special considerations that are time and money consuming. For Casablanca’s addressing locators, an alternative approach was adopted to collect 400 000 points. It took two months, 200 operators and 3500 printed maps to cover a study area of1,226 km2. This paper is to develop an optimized approach based on automated procedure for reintegrating printed maps in a geographic information system (GIS). It saves georeferencing time from 5min to just seconds per document. It insures, more importantly, an accuracy that is between20 cmto1 mfor scales that are between 1/500 and 1/2500. It ensures maps’ integration, independently of base map and coordinates system by introducing the notion of Georeferencing Code (GC).展开更多
The thematic progression Patterns help to clarify the semantic relationships between the sentences and the method of the development in the texts,and they have been one of the important methods to analyze the discours...The thematic progression Patterns help to clarify the semantic relationships between the sentences and the method of the development in the texts,and they have been one of the important methods to analyze the discourse sequences in the text linguistics and discourse analysis(Qi Yucun,1993).With the theoretical framework of Halliday’s theme-rheme theory and the thematic progression patterns coined by Danes and other major scholars,selecting the two addresses made by Xi Jinping and Obama in the APEC CEO Summit in November 9,2014 as the data resource,this article aims to find out the similarities and differences in the choice of Themes and Thematic Progression Patterns and dig out the possible reasons.Since the two addresses are of the same genre but with different languages,new ideas may be provided in the contrastive discourse studies and the theory of contrastive study on Chinese and American addresses will be enriched through this kind of research.展开更多
On June 12th,2008,the China-Korea Forum was held in Shanghai to address hot issues in China's nancial sector such as banking reform,securities market and RMB appreciation,Vice Mayor of Shanghai,o cials from Shangh...On June 12th,2008,the China-Korea Forum was held in Shanghai to address hot issues in China's nancial sector such as banking reform,securities market and RMB appreciation,Vice Mayor of Shanghai,o cials from Shanghai Securities Exchange Research Center and the Korea Financial Service Commission were invited to share their wisdom on these issues.展开更多
The aim of this paper is twofold： firstly, to make an analysis of what have been considered as the most important global problems faced in recent decades as seen by American Presidents through their inaugural address...The aim of this paper is twofold： firstly, to make an analysis of what have been considered as the most important global problems faced in recent decades as seen by American Presidents through their inaugural addresses; and secondly, to consider how both parties have faced these problems. To do this, this paper will cover the period from the inaugural address by President Kennedy to that of President Obama. Although a president has repeated a term of government, only the first speech will be taken into consideration.展开更多
文摘在室内可见光通信中符号间干扰和噪声会严重影响系统性能,K均值(K-means)均衡方法可以抑制光无线信道的影响,但其复杂度较高,且在聚类边界处易出现误判。提出了改进聚类中心点的K-means(Improved Center K-means,IC-Kmeans)算法,通过随机生成足够长的训练序列,然后将训练序列每一簇的均值作为K-means聚类中心,避免了传统K-means反复迭代寻找聚类中心。进一步,提出了基于神经网络的IC-Kmeans(Neural Network Based IC-Kmeans,NNIC-Kmeans)算法,使用反向传播神经网络将接收端二维数据映射至三维空间,以增加不同簇之间混合数据的距离,提高了分类准确性。蒙特卡罗误码率仿真表明,IC-Kmeans均衡和传统K-means算法的误码率性能相当,但可以显著降低复杂度,特别是在信噪比较小时。同时,在室内多径信道模型下,与IC-Kmeans和传统Kmeans均衡相比,NNIC-Kmeans均衡的光正交频分复用系统误码率性能最好。
基金This work is sponsored by the Natural Science Foundation of Heilongjiang Province of China under Grant No.LC2016024Natural Science Foundation of the Jiangsu Higher Education Institutions Grant No.17KJB520044Six Talent Peaks Project in Jiangsu Province No.XYDXX-108.
文摘As an extension of the traditional encryption technology,information hiding has been increasingly used in the fields of communication and network media,and the covert communication technology has gradually developed.The blockchain technology that has emerged in recent years has the characteristics of decentralization and tamper resistance,which can effectively alleviate the disadvantages and problems of traditional covert communication.However,its combination with covert communication thus far has been mostly at the theoretical level.The BLOCCE method,as an early result of the combination of blockchain and covert communication technology,has the problems of low information embedding efficiency,the use of too many Bitcoin addresses,low communication efficiency,and high costs.The present research improved on this method,designed the V-BLOCCE which uses base58 to encrypt the plaintext and reuses the addresses generated by Vanitygen multiple times to embed information.This greatly improves the efficiency of information embedding and decreases the number of Bitcoin addresses used.Under the premise of ensuring the order,the Bitcoin transaction OP_RETURN field is used to store the information required to restore the plaintext and the transactions are issued at the same time to improve the information transmission efficiency.Thus,a more efficient and feasible method for the application of covert communication on the blockchain is proposed.In addition,this paper also provides a more feasible scheme and theoretical support for covert communication in blockchain.
基金supported by the National Key Research and Development Program of China(No.2016YFB0800601)the Key Program of NSFC-Tongyong Union Foundation(No.U1636209)+1 种基金the National Natural Science Foundation of China(61602358)the Key Research and Development Programs of Shaanxi(No.2019ZDLGY13-04,No.2019ZDLGY13-07)。
文摘The static and predictable characteristics of cyber systems give attackers an asymmetric advantage in gathering useful information and launching attacks.To reverse this asymmetric advantage,a new defense idea,called Moving Target Defense(MTD),has been proposed to provide additional selectable measures to complement traditional defense.However,MTD is unable to defeat the sophisticated attacker with fingerprint tracking ability.To overcome this limitation,we go one step beyond and show that the combination of MTD and Deception-based Cyber Defense(DCD)can achieve higher performance than either of them.In particular,we first introduce and formalize a novel attacker model named Scan and Foothold Attack(SFA)based on cyber kill chain.Afterwards,we develop probabilistic models for SFA defenses to provide a deeper analysis of the theoretical effect under different defense strategies.These models quantify attack success probability and the probability that the attacker will be deceived under various conditions,such as the size of address space,and the number of hosts,attack analysis time.Finally,the experimental results show that the actual defense effect of each strategy almost perfectly follows its probabilistic model.Also,the defense strategy of combining address mutation and fingerprint camouflage can achieve a better defense effect than the single address mutation.
基金supported by the National Key R&D Program of China(Project Number:2022YFB2902100).
文摘To ensure the extreme performances of the new 6G services,applications will be deployed at deep edge,resulting in a serious challenge of distributed application addressing.This paper traces back the latest development of mobile network application addressing,analyzes two novel addressing methods in carrier network,and puts forward a 6G endogenous application addressing scheme by integrating some of their essence into the 6G network architecture,combining the new 6G capabilities of computing&network convergence,endogenous intelligence,and communication-sensing integration.This paper further illustrates how that the proposed method works in 6G networks and gives preliminary experimental verification.
文摘This thesis aims at exploring meanings of different addresses and their correct and suitable translations in both Chinese and English. After the introduction to the definition and meaning of addresses, the whole thesis probes into this problem from two aspects: the reasons which lead to the differences in addresses among relatives in both Chinese and English, and the ways how to translate addresses properly according to the situations. With the exploration, the writer hopes to introduce the cultural differences from the perspective of translations of addresses.
文摘The United Kingdom are still facing great challenges in all aspects after about half a year's struggle since they had made the decision to Brexit. The authorities are also trying to convince the public of its authorities by all means, especially by public speeches. This paper is going to analyze how the Queen and the Prime Minster try to convince their public of a better future in their New Year Addresses through the method of cluster analysis.
文摘The article mainly studies the application strategy of automatic addressable single-lamp control technology in tunnel lighting.It encompasses an introduction to this technology,an analysis of the tunnel lighting system using automatic addressable single-lamp control technology,and outlines the main development direction for this technology in modern tunnel lighting.The aim is to offer insights that can inform the rational deployment of this technology,thereby enhancing the lighting control effectiveness in modern tunnels and meeting their specific lighting requirements more effectively.
文摘Addresses are important data for urban applications. About 80% of the information local authorities use have a geographic component that is generally related to addresses. Addressing systems efficiency depend on the quality of addresses locators. There are several methods to collect data. Surveys from the field are essential: GPS and pre-printed maps can be used to achieve this goal. GPS surveys from the field may be a solution, but it remains practical only for limited areas. To insure an accepted accuracy, GPS methods need special considerations that are time and money consuming. For Casablanca’s addressing locators, an alternative approach was adopted to collect 400 000 points. It took two months, 200 operators and 3500 printed maps to cover a study area of1,226 km2. This paper is to develop an optimized approach based on automated procedure for reintegrating printed maps in a geographic information system (GIS). It saves georeferencing time from 5min to just seconds per document. It insures, more importantly, an accuracy that is between20 cmto1 mfor scales that are between 1/500 and 1/2500. It ensures maps’ integration, independently of base map and coordinates system by introducing the notion of Georeferencing Code (GC).
文摘The thematic progression Patterns help to clarify the semantic relationships between the sentences and the method of the development in the texts,and they have been one of the important methods to analyze the discourse sequences in the text linguistics and discourse analysis(Qi Yucun,1993).With the theoretical framework of Halliday’s theme-rheme theory and the thematic progression patterns coined by Danes and other major scholars,selecting the two addresses made by Xi Jinping and Obama in the APEC CEO Summit in November 9,2014 as the data resource,this article aims to find out the similarities and differences in the choice of Themes and Thematic Progression Patterns and dig out the possible reasons.Since the two addresses are of the same genre but with different languages,new ideas may be provided in the contrastive discourse studies and the theory of contrastive study on Chinese and American addresses will be enriched through this kind of research.
文摘On June 12th,2008,the China-Korea Forum was held in Shanghai to address hot issues in China's nancial sector such as banking reform,securities market and RMB appreciation,Vice Mayor of Shanghai,o cials from Shanghai Securities Exchange Research Center and the Korea Financial Service Commission were invited to share their wisdom on these issues.
文摘The aim of this paper is twofold： firstly, to make an analysis of what have been considered as the most important global problems faced in recent decades as seen by American Presidents through their inaugural addresses; and secondly, to consider how both parties have faced these problems. To do this, this paper will cover the period from the inaugural address by President Kennedy to that of President Obama. Although a president has repeated a term of government, only the first speech will be taken into consideration.
