A Hierarchical Autonomous System Based Topology Control Algorithm in Space Information Network

( Wei Zhang ),( Gengxin Zhang ),( Liang Gou ),( Bo Kong ),( Dongming Bian ) 한국인터넷정보학회 2015 KSII Transactions on Internet and Information Syst Vol.9 No.9

This article investigates the topology control problem in the space information network (SIN) using a hierarchical autonomous system (AS) approach. We propose an AS network topology control (AS-TC) algorithm to minimize the time delay in the SIN. Compared with most existing approaches for SIN where either the purely centralized or the purely distributed control method is adopted, the proposed algorithm is a hybrid control method. In order to reduce the cost of control, the control message exchange is constrained among neighboring sub-AS networks. We prove that the proposed algorithm achieve logical k-connectivity on the condition that the original physical topology is k-connectivity. Simulation results validate the theoretic analysis and effectiveness of the AS-TC algorithm.

An Opinion Leaders Detecting Algorithm in Multi-relationship Online Social Networks

Weihua Zhang,Gengxin Sun,Sheng Bin 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.5

Opinion leaders in online social networks are important for a lot of applications in various fields such as public opinion propagation, marketing management, administrative science and even politics. There are often many kinds of relationships in an online social network. Detecting and identifying opinion leaders depending on any one kind of relationship is all accurate. In this paper, node importance analysis in multi-relationship online social network was proposed based on signaling spreading, and considering the characteristics of multiple relationships which would interrelate with each other. Through node importance, a novel opinion leaders detecting algorithm is proposed and approved to be efficient by experiments described in the paper.

A High Spectral Efficiency CDMA System Based on Expanded Generalized Complementary Orthogonal Code Groups

Peijian Zhang,Aili Qu,Gengxin Sun,Fengjing Shao,Xing Yang,Daoben Li 보안공학연구지원센터 2015 International Journal of Future Generation Communi Vol.8 No.6

A new CDMA system which uses fractional chip shift expanded generalized complementary orthogonal code groups as spectrum spreading code sequences and offer high spectral efficiency is introduced in the paper. This new CDMA system is totally different with conventional CDMA system in access codes designing and spectrum spreading process. In this CDMA system, the access codes of different cells keep orthogonality, which eliminates inter cells interferences (ACI) by aperiodic cross-correlation function (CCF). The spreading process of new CDMA system introduces inter symbols interference like overlap time division multiplexing (OVTDM) deliberately so as to improve spectral efficiency. The construction of expanded generalized complementary orthogonal code groups, shift method, principle of new CDMA system are explained respectively. Analysis and simulation results verify the validity of this new CDMA system.

Electronic Word-of-mouth Marketing in E-commerce based on Online Product Reviews

PengPeng Zhang,Sheng Bin,Gengxin Sun 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.8

In E-commerce, purchase decisions of consumers are often strongly influenced by people who consumers know and trust, and word-of-mouth (WOM) is the most important factor when consumers are making a purchase decision. Many online consumers tend to wait for the opinions of early consumers before making a purchase decision to reduce the risk of buying products. So numerous E-commerce websites provide product reviews function for consumers to publicize their personal reviews of purchased products and thus facilitate word-of-mouth communication among consumers. This paper describes word-of-mouth, as a potentially cost-effective means for marketing, especially influence of opinion leaders in electronic word-of-mouth marketing.

A Novel Task Communication and Scheduling Algorithm for NoC-based MPSoC

Weihua Zhang,Gengxin Sun,Sheng Bin 보안공학연구지원센터 2015 International Journal of Smart Home Vol.9 No.10

With the high performance demand, recent embedded systems are mostly based on NoC (Network-on-Chip) architectures, which would bring complex on-chip communication and scheduling problems. In this paper, a novel task scheduling algorithm which statically schedules both communication transactions and computation tasks onto heterogeneous NoC architectures under real-time constraints is presented. Our algorithm is capable of assigning tasks onto different processing elements (PE) automatically and scheduling their execution. We map tasks onto an 8× 8 NoC-based MPSoC to show that our scheduling algorithm leads to reduction in the total execution time, energy consumption. Experimental results show that for a multimedia application, more than 40% energy savings have been observed compared to the schedules generated by a standard scheduler.

Constant Envelope Enhanced FQPSK and Its Performance Analysis

Xie, Zhidong,Zhang, Gengxin,Bian, Dongming The Korea Institute of Information and Commucation 2011 Journal of communications and networks Vol.13 No.5

It's a challenging task to design a high performance modulation for satellite and space communications due to the limited power and bandwidth resource. Constant envelope modulation is an attractive scheme to be used in such cases for their needlessness of input power back-off about 2~3 dB for avoidance of nonlinear distortion induced by high power amplifier. The envelope of Feher quadrature phase shift keying (FQPSK) has a least fluctuation of 0.18 dB (quasi constant envelope) and can be further improved. This paper improves FQPSK by defining a set of new waveform functions, which changes FQPSK to be a strictly constant envelope modulation. The performance of the FQPSK adopting new waveform is justified by analysis and simulation. The study results show that the novel FQPSK is immune to the impact of HPA and outperforms conventional FQPSK on bit error rate (BER) performance. The BER performance of this novel modulation is better than that of FQPSK by more than 0.5 dB at least and 2 dB at most.

Data Dissemination in Wireless Sensor Networks with Instantly Decodable Network Coding

Gou, Liang,Zhang, Gengxin,Bian, Dongming,Zhang, Wei,Xie, Zhidong The Korea Institute of Information and Commucation 2016 Journal of communications and networks Vol.18 No.5

Wireless sensor networks (WSNs) are widely applied in monitoring and control of environment parameters. It is sometimes necessary to disseminate data through wireless links after they are deployed in order to adjust configuration parameters of sensors or distribute management commands and queries to sensors. Several approaches have been proposed recently for data dissemination in WSNs. However, none of these approaches achieves both high efficiency and low complexity simultaneously. To address this problem, cluster-tree based network architecture, which divides a WSN into hierarchies and clusters is proposed. Upon this architecture, data is delivered from base station to all sensors in clusters hierarchy by hierarchy. In each cluster, father broadcasts data to all his children with instantly decodable network coding (IDNC), and a novel scheme targeting to maximize total transmission gain (MTTG) is proposed. This scheme employs a new packet scheduling algorithm to select IDNC packets, which uses weight status feedback matrix (WSFM) directly. Analysis and simulation results indicate that the transmission efficiency approximate to the best existing approach maximum weight clique, but with much lower computational overhead. Hence, the energy efficiency achieves both in data transmission and processing.

Efficient Distributed Storage for Space Information Network Based on Fountain Codes and Probabilistic Broadcasting

( Bo Kong ),( Gengxin Zhang ),( Wei Zhang ),( Feihong Dong ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.6

This article investigates the distributed data storage problem in the space information network (SIN) using distributed fountain codes. Since space nodes in the SIN are resource-limited, in order to reduce energy consumption while improving the storage reliability, an efficient distributed storage based on fountain codes and probabilistic broadcasting (DSFPB) strategy is proposed. In the proposed strategy, source packets are disseminated among the entire network according to probabilistic broadcasting (PBcast), and the final degree distribution is close to the desired robust soliton distribution (RSD), this is benefited from the appropriate packets encoding procedure of the proposed strategy. As presented by the analysis and simulations, the total cost of data dissemination is greatly reduced compared with existing representative strategies, while improving the decoding performance.

Tag-Based Interest-Matching Users Discovery Approach in Online Social Network

Sheng Bin,Gengxin Sun,Peijian Zhang,Yixin Zhou 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.5

With the popularity of online social networks, such as Facebook, YouTube and Douban, have become a channel for fast information propagation and influence. The problem of discovering common interests shared by groups of users has become one of the central researches because it helps to connect users with common interests and can eventually influence as many users with common interests in the online social network as possible. Unfortunately, most of existing related works have only focused on the network topologies and so unable to identify the common interests of users who have no online connections. In an online social network, users tend to use descriptive tags to annotate the contents that they are interested in. User-generated tags are consistent with the content they are attached to. Thus, patterns of frequent co-occurrences of user tags can be used to characterize and capture topics of user interests. In this paper, we propose a novel common interests discovery approach based on user-generated tags to discover the set of interest-matching users whose interests are similar. The experiment results show that our approach can effectively discover user communities with common interests no matter if they have any online connections.

Data Dissemination in Wireless Sensor Networks with Instantly Decodable Network Coding

Liang Gou,Gengxin Zhang,Dongming Bian,Wei Zhang,Zhidong Xie 한국통신학회 2016 Journal of communications and networks Vol.18 No.5

Wireless sensor networks (WSNs) are widely applied inmonitoring and control of environment parameters. It is sometimesnecessary to disseminate data through wireless links after they aredeployed in order to adjust configuration parameters of sensors ordistribute management commands and queries to sensors. Severalapproaches have been proposed recently for data dissemination inWSNs. However, none of these approaches achieves both high effi-ciency and low complexity simultaneously. To address this problem,cluster-tree based network architecture, which divides aWSN intohierarchies and clusters is proposed. Upon this architecture, datais delivered from base station to all sensors in clusters hierarchyby hierarchy. In each cluster, father broadcasts data to all his chil-dren with instantly decodable network coding (IDNC), and a novelscheme targeting to maximize total transmission gain (MTTG) isproposed. This scheme employs a new packet scheduling algorithmto select IDNC packets, which uses weight status feedback matrix(WSFM) directly. Analysis and simulation results indicate that thetransmission efficiency approximate to the best existing approachmaximum weight clique, but with much lower computational over-head. Hence, the energy efficiency achieves both in data transmis-sion and processing.