MHDT: A Deep-Learning-based Text Detection Algorithm for Unstructured Data in Banking

Conference
Shenglan Ma, Lingling Yang, Hao Wang, Hong Xiao, Hong-Ning Dai, Shuhan Cheng, Tongsen Wan
11th International Conference on Machine Learning and Computing, 2019
Publication year: 2019

Wide & Deep Convolutional Neural Networks for Electricity-Theft Detection to Secure Smart Grids

Journal
Zibin Zheng, Yatao Yang, Xiangdong Niu, Hong-Ning Dai, Yuren Zhou
IEEE Transactions on Industrial Informatics,vol. 14, no. 4, pp. 1606-1615, April 2018
Publication year: 2018

Electricity theft can be harmful to power grid suppliers and cause economic losses. Integrating information flows with energy flows, smart grids can help to solve the problem of electricity theft owning to the availability of massive data generated from smart grids. The data analysis on the data of smart grids is helpful in detecting electricity theft because of the abnormal electricity consumption pattern of energy thieves. However, the existing methods have poor detection accuracy of electricity-theft since most of them were conducted on one dimensional (1-D) electricity consumption data and failed to capture the periodicity of electricity consumption. In this paper, we originally propose a novel electricity-theft detection method based on Wide & Deep Convolutional Neural Networks (CNN) model to address the above concerns. In particular, Wide & Deep CNN model consists of two components: the Wide component and the Deep CNN component. The Deep CNN component can accurately identify the non-periodicity of electricity-theft and the periodicity of normal electricity usage based on two dimensional (2-D) electricity consumption data. Meanwhile, the Wide component can capture the global features of 1-D electricity consumption data. As a result, Wide & Deep CNN model can achieve the excellent performance in electricity-theft detection. Extensive experiments based on realistic dataset show that Wide & Deep CNN model outperforms other existing methods.

We publish the dataset used in this paper to promote the research in this area. The dataset can be found through this link: https://github.com/henryRDlab/ElectricityTheftDetection/

When Friendly Jamming Meets Wireless Energy Transfer

Conference
Qi Sun, Hong-Ning Dai, Qiu Wang, Xuran Li, Hao Wang
IEEE International Conference on Green Computing and Communications 2018, Halifax, Canada
Publication year: 2018

Friendly-jamming schemes can effectively reduce the eavesdropping risk in wireless networks by generating sufficient interference to prevent eavesdroppers from snooping confidential communications. However, this type of anti-eavesdropping schemes can also affect the normal communications due to the interference to legitimate users. On the other hand, Wireless Energy Transfer (WET) technology has received much attention recently since WET allows a node to obtain the energy from electromagnetic radiation. In this paper, we integrate the friendly-jamming scheme with WET. We call this scheme as Wireless-Jamming-Energy-Transfer (WJET). This scheme can translate the harmful interference radiated from jammers into the energy harvested by legitimate transmitters. In order to evaluate the effectiveness of this scheme, we establish an analytical model to analyze the transmission probability and the eavesdropping probability. Simulations verify that WJET scheme can simultaneously decrease the eavesdropping probability of eavesdroppers and increase the transmission probability of legitimate users. In addition, we investigate the density of jammers to achieve the optimal transmission probability according to various channel conditions, the density of transmitters and the transmission power of jammers.

Sentiment Analysis of Chinese Microblog Based on Stacked Bidirectional LSTM

Conference
Yue Lu, Junhao Zhou, Hong-Ning Dai, Hao Wang, Hong Xiao
The 15th International Symposium on Pervasive Systems, Algorithms and Networks (I-SPAN 2018)
Publication year: 2018

Recently, sentiment analysis on microblogs has received extensive attention recently. Most of previous studies focus on identifying sentiment orientation by encoding as many word properties as possible. However, most of them ignore the long-range dependencies of words (i.e., contextual features), which are essentially important in the sentiment analysis. In this paper, we propose a sentiment analysis method by incorporating Continuous Bag-of-Words (CBOW) model and Stacked Bidirectional long short-term memory (Stacked Bi-LSTM) model to enhance the performance of sentiment prediction. Firstly, a word embedding model, CBOW model, is employed to capture semantic features of words and transfer words into high dimensional word vectors. Secondly, we introduce Stacked Bi-LSTM model to conduct the feature extraction of sequential word vectors at a deep level. Finally, a binary softmax classifier utilizes semantic and contextual features to predict the sentiment orientation. Extensive experiments on real dataset collected from Weibo (i.e., one of the most popular Chinese microblogs) show that our proposed approach achieves better performance than other machine learning models.

Nudging Data Privacy Management of Open Banking based on Blockchain

Conference
Shenglan Ma, Chaonian Guo, Hao Wang, Hong-Ning Dai, Shuhan Cheng, Ruihua Yi
The 15th International Symposium on Pervasive Systems, Algorithms and Networks (I-SPAN 2018)
Publication year: 2018

Open banking brings both the opportunities and challenges to banks all over the world. Due to the different economic development levels of each country and the gaps among financial environment maturity, all countries have different strategies and regulations towards the privacy protection of data in financial scenes, such as the General Data Protection Regulation (GDPR) by European Union (EU). A blockchain as a continuously growing list of records managed by a peer-to-peer network is widely used in various application scenarios, and can protect the privacy of financial data. However, financial blockchain still poses some problems that cannot fully meet the data protection needs. In order to address the existing problems, this paper proposes a new blockchain-based data privacy management framework. The framework consists of three components: a data privacy classification method according to the characteristics of financial data and a new collaborative-filtering-based model and a confirmation data disclosure scheme for customer strategies based on the Nudge Theory. We implement a prototype and propose a set of algorithms for this management framework.

Fraud Risk Monitoring System for E-Banking Transactions

Conference
Chaonian Guo , Hao Wang, Hong-Ning Dai, Shuhan Cheng, Tongsen Wang
IEEE Cyber Science and Technology Congress (CyberSciTech) 2018, Athens, Greece
Publication year: 2018

Fraudulent e-banking transactions have caused great economic loss every year. Thus, it is important for financial institutions to make the e-banking system more secure, and improve the fraud detection system. Researches for the fraud risk monitoring are mainly focused on score rules and data driven model. The score rule is based on expertise, which is vulnerable to new patterns of frauds. Data driven model is based on machine learning classifiers, and usually has to handle the unbalanced classification problem. In this paper, we propose a novel fraud risk monitoring system for e-banking transactions. Model of score rules for online real-time transactions and offline historical transactions are combined together for the transaction fraud detection. Parallel big data framework: Kafka, Spark and MPP GBase which integrated with a machine learning algorithm is presented to handle offline massive transaction logs. Experimental results show the effectiveness of our proposed fraud risk monitoring system over a real massive dataset of e-banking transactions. This evaluation leads us to identify research gaps and challenges to consider in future research endeavours.

Detection Performance of Packet Arrival under Downclocking for Mobile Edge Computing

Journal
Zhimin wang, Qinglin Zhao, Fangxin Xu, Hong-Ning Dai, Yujun Zhang
Wireless Communications and Mobile Computing, 2018
Publication year: 2018

Mobile edge computing (MEC) enables battery-powered mobile nodes to acquire information technology services at the network edge. These nodes desire to enjoy their service under power saving. The sampling rate invariant detection (SRID) is the first downclocking WiFi technique that can achieve this objective. With SRID, a node detects one packet arrival at a downclocked rate. Upon a successful detection, the node reverts to a full-clocked rate to receive the packet immediately. To ensure that a node acquires its service immediately, the detection performance (namely, the miss-detection probability and the false-alarm probability) of SRID is of importance. This paper is the first one to theoretically study the crucial impact of SRID attributes (e.g., tolerance threshold, correlation threshold, and energy ratio threshold) on the packet detection performance. Extensive Monte Carlo experiments show that our theoretical model is very accurate. This study can help system developers set reasonable system parameters for WiFi downclocking.

Data Analysis on Video Streaming QoE over Mobile Networks

Journal
Qingyong Wang, Hong-Ning Dai, Di Wu, Hong Xiao
EURASIP Journal on Wireless Communications and Networking, 2018
Publication year: 2018

One of recent proposals on standardizing quality of user experience (QoE) of video streaming over mobile network is is video Mean Opinion Score (vMOS), which can model QoE of video streaming in 5 discrete grades. However, there are few studies on quantifying vMOS and investigating the relationship between vMOS and other Quality of Service (QoS) parameters. In this paper, we address this concern by proposing a novel data analytical framework based on video streaming QoE data. In particular, our analytical model consists of K-means clustering and logistic regression. This model integrates the benefits of both these two models. Moreover, we conduct extensive experiments on realistic dataset and verify the accuracy of our proposed model. The results show that our proposed framework outperforms other existing methods in terms of prediction accuracy. Moreover, our results also show that vMOS is essentially affected by many QoS parameters such as initial buffering latency, stalling ratio and stalling times. Our results offer a number of insights in improving QoE of video streaming over mobile networks.

We publish the dataset used in this paper to promote the research in this area. The dataset can be found in https://github.com/henryRDlab/VMOS.

 

Connectivity of Underwater Cognitive Acoustic Networks under Spectrum Constraint

Conference
Qiu Wang, Hong-Ning Dai, Hao Wang, Qubeijian Wang
The 13th ACM International Conference on Underwater Networks & Systems, 2018
Publication year: 2018

There is an extensive attention on underwater cognitive acoustic networks (UCANs) since acoustic spectrum becomes deficient owning to the proliferation of human activity in ocean. This paper presents an overview of our recent progress in investigating the connectivity of secondary users (SUs) in UCANs. In particular, this model takes both topological connectivity and spectrum availability into account. Simulation results verify the accuracy of the proposed model.

Connectivity of Underlay Cognitive Radio Networks with Directional Antennas

Journal
Qiu Wang, Hong-Ning Dai, Orestis Georgiou, Zhiguo Shi, Wei Zhang
IEEE Transactions on Vehicular Technology, Vol 67, pp. 7003 - 7017, Aug. 2018
Publication year: 2018

In underlay cognitive radio networks (CRNs), the connectivity of secondary users (SUs) is difficult to be guaranteed due to the existence of primary users (PUs). Most prior studies only consider cognitive radio networks equipped with omni-directional antennas causing high interference at SUs. We name such CRNs with omni-directional antennas as Omn-CRNs. Compared with an omni-directional antenna, a directional antenna can concentrate the transmitting/receiving capability at a certain direction, consequently resulting in the less interference. In this paper, we investigate the connectivity of SUs in CRNs with directional antennas (named as Dir-CRNs). In particular, we derive closed-form expressions of the connectivity of SUs of both Dir-CRNs and Omn-CRNs, thus enabling tractability. We show that the connectivity of SUs is mainly affected by two constraints: the spectrum availability of SUs and the topological connectivity of SUs. Extensive simulations validate the accuracy of our proposed models. Meanwhile, we also show that Dir-CRNs can have higher connectivity than Omn-CRNs mainly due to the lower interference, the higher spectrum availability and the higher topological connectivity brought by directional antennas. Moreover, we also extend our analysis with consideration transmission power efficiency. The simulation results show that Dir-CRNs require less transmission power to establish links than Omn-CRNs. We further investigate the throughput capacity of SUs, which is shown to heavily depend on the connectivity of SUs.

Connectivity of Cognitive Radio Ad Hoc Networks with Directional Antennas

Journal
Yuanyuan Wang, Qiu Wang, Hong-Ning Dai, Haibo Wang, Zhiguo Shi
Wireless Networks, Volume 24, Issue 8, Pages 3045–3061, November
Publication year: 2018

In cognitive radio ad hoc networks, omni-directional antennas are typically used at both primary users (PUs) and secondary users (SUs), which can cause high interference. We name such cognitive radio ad hoc networks with omni-directional antennas as OMN-CRAHNs. Different from omni-directional antennas, directional antennas can concentrate the transmission on desired directions and can consequently reduce interference in undesired directions. In this paper, we investigate both the local connectivity and the overall connectivity of cognitive radio ad hoc networks with directional antennas (DIR-CRAHNs), in which both PUs and SUs are equipped with directional antennas. In particular, we establish a theoretical framework to analyze both the probability of node isolation and the probability of connectivity of DIR-CRAHNs and OMN-CRAHNs. Our analytical results show that DIR-CRAHNs can have higher connectivity than OMN-CRAHNs.

BRAINS: Joint Bandwidth-Relay Allocation in Multi-Homing Cooperative D2D Networks

Journal
Long Chen, Jigang Wu, Hong-Ning Dai, Xiaoxia Huang
IEEE Transactions on Vehicular Technology, Vol 67, pp. 5387 - 5398, June 2018
Publication year: 2018

Devices with multi-homing capability can access multiple wireless access networks simultaneously. As an emerging technique, cooperative device to device (CD2D) communication has been considered to be a solution to capacity shortage problem. Combining multi-homing and CD2D techniques together can potentially improve network performance. We propose a novel multi-homing CD2D (MH-CD2D) network, in which multiple homing mobile devices (MMDs) act as relays for the cooperative communications of ordinary mobile devices (OMDs). We formulate such joint bandwidth-relay allocation problem as a two-stage game, in order to deal with two challenges: 1) how to design incentive mechanisms motivating MMDs to lease spare bandwidths to OMDs; 2) how to help OMDs to choose appropriate MMD relays. In the first stage, we use a non-cooperative game to model the competition between MMDs in terms of shared bandwidth and price. In the second stage, we model the behavior of OMDs selecting MMDs by an evolutionary game. We prove that there exists Nash equilibrium in the game and propose a distributed incentive scheme named IMES to solve the joint bandwidth-relay allocation problem. Extensive simulation results show that the equilibrium can be achieved and the best response price of one MMD increases with the other’s best price in the Stackelberg game. The utility of MMDs increases with the number of OMDs in each OMD group at the evolutionary equilibrium. The proposed algorithms are able to reduce the average service delay by more than 25% in comparison to the randomized scheme which is frequently used in the most existing works. On average, IMES outperforms existing scheme by about 20.37% in terms of utility of MMDs.

Blockchain Challenges and Opportunities: A Survey

Journal
Zibin Zheng, Shaoan Xie, Hong-Ning Dai, Huaimin Wang and Xiangping Chen
International Journal of Web and Grid Services (IJWGS), Vol. 14, No. 4, 2018
Publication year: 2018

Blockchain has numerous benefits such as decentralization, persistency, anonymity and auditability. There is a wide spectrum of blockchain applications ranging from cryptocurrency, financial services, risk management, Internet of Things to public and social services. Although a number of studies focus on using the blockchain technology in various application aspects, there is no comprehensive survey on the blockchain technology in both technological and application perspectives. To fill this gap, we conduct a comprehensive survey on the blockchain technology. In particular, this paper gives the blockchain taxonomy, introduces typical blockchain consensus algorithms, reviews blockchain applications and discusses technical challenges as well as recent advances in tackling the challenges. Moreover, this paper also points out the future directions in the blockchain technology.

 

[This is the first comprehensive survey on blockchain from technological and application perspectives. This paper was essentially completed in 2016 and formally published by International Journal of Web and Grid Services (IJWGS) in Oct. 2018). http://dx.doi.org/10.1504/IJWGS.2018.095647]

Banking Comprehensive Risk Management System based on Big Data Architecture of Hybrid Processing Engines and Databases

Conference
Shenglan Ma, Fangkai Xie, Hao Wang, Hong-Ning Dai, Ran Tao, Ruihua Yi, Tongsen Wang
IEEE International Conference on Cloud and Big Data Computing
Publication year: 2018

Banks are shifting from a simple credit risk management model to the comprehensive risk management model. Banking risks come from many channels and systems. Big data technology provides an innovative and effective solution for data management, and thus is suitable to be applied in the risk management scenarios that require high-quality data and complex data analysis. This paper firstly proposes big data architecture of hybrid processing engines and databases. This architecture uses Hadoop ecosystem with ETL and Spark processing engines, and using massive parallel processing databases (MPP), transactional databases, and HDFS. Then a banking comprehensive risk management system prototype based on the proposed big data architecture is implemented. Comparisons and evaluations clearly demonstrate that the proposed system has better performance.

An Efficient Greedy Algorithm for Wideband Spectrum Sensing for Cognitive Radio Networks

Conference
Wajeeha Nasar, Abdur Rahman Maud, Hao Wang, Hong-Ning Dai
IEEE International Conference on Green Computing and Communications 2018, Halifax, Canada
Publication year: 2018

In Cognitive Radio Networks (CRNs), secondary users (unlicensed users) can use spectrum when their transmissions cause no interference to primary users (licensed users). The spectrum sensing is a necessity to achieve this spectrum sharing scheme. However, it is challenging to achieve spectrum sensing due to the computational complexity. In this paper, we propose a novel greedy algorithm to solve the wideband spectrum compressive sensing problem. The main idea of our algorithm is to reconstruct spectrum for wideband signals without any prior knowledge of spectrum. The proposed greedy algorithm will reconstruct wideband spectrum along with sub-bands of frequency in which spectrum is divided. The proposed greedy algorithm is intelligent enough to sense the range of each sub-band of frequency and detect them efficiently. Extensive simulation results show that our proposed algorithm outperforms existing greedy algorithms such as Orthogonal Matching Pursuit (OMP) in terms of accuracy, computational speed and Block OMP in terms of computational speed.

A Novel Friendly Jamming Scheme in Industrial Crowdsensing Networks against Eavesdropping Attack

Journal
Xuran Li, Qiu Wang, Hong-Ning Dai, Hao Wang
Sensors, 2018
Publication year: 2018

Eavesdropping attack is one of the most serious threats in red industrial crowdsensing networks. In this paper, we propose a novel anti-eavesdropping scheme by introducing friendly jammers to an red industrial crowdsensing network. In particular, we establish a theoretical framework considering both the probability of eavesdropping attacks and the probability of successful transmission to evaluate the effectiveness of our scheme. Our framework takes into account various channel conditions such as path loss, Rayleigh fading, and the antenna type of friendly jammers. Our results show that using jammers in red industrial crowdsensing networks can effectively reduce the eavesdropping risk while having no significant influence on legitimate communications.

A Blockchain-based Risk and Information System Control Framework

Conference
Shenglan Ma, Hao Wang, Hong-Ning Dai, Shuhan Cheng, Ruihua Yi, Tongsen Wang
IEEE Cyber Science and Technology Congress (CyberSciTech), 2018, Athens, Greece
Publication year: 2018

Risk and Information System Control Framework in business includes the methods and processes to manage risks and seize opportunities that involves identifying particular risk events relevant to the objectives, assessing them in terms of likelihood and magnitude of impact, determining a response strategy, and monitoring progress. In order to achieve better support for the backtracking, traceability, irreversibility, and credible requirements of risk registration table data in the framework, this paper proposes a blockchain-based risk and information system control framework. A risk association tree is designed for combining summarized risk item ledgers with risk assessment ledgers and risk response ledgers based on the Merkle Tree. Three proposed smart contracts are used in risk identification, risk assessment, risk response and mitigation, and risk and control monitoring and reporting processes. We implement a prototype for this framework.

Transmission probability of energy harvesting-based cognitive radio networks with directional antennas

Conference
Qiu Wang, Hong-Ning Dai, Wei Zhang
Proceedings of the 23rd Asia Pacific Conference on Communications (APCC 2017), Perth, Australia, 2017
Publication year: 2017

Throughput Analysis of the Two-way Relay System with Network Coding and Energy Harvesting

Conference
Haifeng Cao, Liqun Fu, Hong-Ning Dai
Proceedings of IEEE International Conference on Communications (ICC), Paris, France, 2017
Publication year: 2017

This paper studies the throughput performance of a two-way energy harvesting relaying system. Network Coding and Energy Harvesting are promising techniques that can improve the transmission efficiency and the energy efficiency of wireless systems, respectively. In particular, we focus on the energy harvesting system with the power splitting-based relaying (PSR) protocol, and consider both the amplify-and-forward (AF) relaying and decode-and-forward (DF) relaying methods for the network coding. We successfully derive the expressions for both the outage probability and the system throughput for each case. It can be shown that DF relaying system outperforms AF relaying system in terms of both the outage probability and the throughput. Furthermore, simulations show that the throughput gain brought by network coding highly depends on the signal-to-noise ratio (SNR) at the receiver. The throughput gain can be up to 33% in the high SNR region.

Performance Analysis of Detecting Packet Arrival for Downclocking Wi-Fi

Conference
Zhimin Wang, Qinglin Zhao, Fangxin Xu, Hong-Ning Dai
Proceedings of International Conference on Identification, Information and Knowledge in the Internet of Things (IIKI), Qufu, China, 2017
Publication year: 2017

On Modeling of Eavesdropping Behavior in Underwater Acoustic Sensor Networks

Conference
Qiu Wang, Hong-Ning Dai
Proceedings of 18th International Symposium on a World of Wireless, Mobile and Multimedia Networks (WoWMoM), Macau, 2017 (PhD forum Session)
Publication year: 2017

On Connectivity of Wireless Sensor Networks with Directional Antennas

Journal
Qiu Wang, Hong-Ning Dai, Zibin Zheng, Muhammad Imran, Athanasios V. Vasilakos
Sensors, vol. 17, no. 1, 2017
Publication year: 2017

In this paper, we investigate the network connectivity of wireless sensor networks with directional antennas. In particular, we establish a general framework to analyze the network connectivity while considering various antenna models and the channel randomness. Since existing directional antenna models have their pros and cons in the accuracy of reflecting realistic antennas and the computational complexity, we propose a new analytical directional antenna model called the iris model to balance the accuracy against the complexity. We conduct extensive simulations to evaluate the analytical framework. Our results show that our proposed analytical model on the network connectivity is accurate, and our iris antenna model can provide a better approximation to realistic directional antennas than other existing antenna models.

On Capacity and Delay of Multi-channel Wireless Networks with Infrastructure Support

Journal
Hong-Ning Dai, Raymond Chi-Wing Wong, Hao Wang
IEEE Transactions on Vehicular Technology, vol. 66, no. 2, pp. 1589-1604, Feb. 2017
Publication year: 2017

In this paper, we propose a novel multichannel network with infrastructure support, which is called an MC-IS network, that has not been studied in the literature. To the best of our knowledge, we are the first to study such an MC-IS network. Our proposed MC-IS network has a number of advantages over three existing conventional networks: a single-channel wireless ad hoc network (called an SC-AH network), a multichannel wireless ad hoc network (called an MC-AH network), and a single-channel network with infrastructure support (called an SC-IS network). In particular, the network capacity of our proposed MC-IS network is √n log n times higher than that of an SC-AH network and an MC-AH network and the same as that of an SC-IS network, where n is the number of nodes in the network. The average delay of our MC-IS network is √log n/n times lower than that of an SC-AH network and an MC-AH network and min {CI, m} times lower than the average delay of an SC-IS network, where CI and m denote the number of channels dedicated for infrastructure communications and the number of interfaces mounted at each infrastructure node, respectively. Our analysis on an MC-IS network equipped with omnidirectional antennas has been extended to an MC-IS network equipped with directional antennas only, which are named as an MC-IS-DA network. We show that an MC-IS-DA network has an even lower delay of c/(⌊2π/θ⌋ · CI) compared with an SC-IS network and our MC-IS network. For example, when CI = 12 and θ = π/12, an MC-IS-DA can further reduce the delay by 24 times lower than that of an MC-IS network and by 288 times lower than that of an SC-IS network.

Link Connectivity and Coverage of Underwater Cognitive Acoustic Networks under Spectrum Constraint

Journal
Qiu Wang, Hong-Ning Dai, Chak Fong Cheang, Hao Wang
Sensors 2017, 17(12), 2839
Publication year: 2017

Extensive attention has been given to the use of cognitive radio technology in underwater acoustic networks since the acoustic spectrum became scarce due to the proliferation of human aquatic activities. Most of the recent studies on underwater cognitive acoustic networks (UCANs) mainly focus on spectrum management or protocol design. Few efforts have addressed the quality-of-service (QoS) of UCANs. In UCANs, secondary users (SUs) have lower priority to use acoustic spectrum than primary users (PUs) with higher priority to access spectrum. As a result, the QoS of SUs is difficult to ensure in UCANs. This paper proposes an analytical model to investigate the link connectivity and the probability of coverage of SUs in UCANs. In particular, this model takes both topological connectivity and spectrum availability into account, though spectrum availability has been ignored in most recent studies. We conduct extensive simulations to evaluate the effectiveness and the accuracy of our proposed model. Simulation results show that our proposed model is quite accurate. Besides, our results also imply that the link connectivity and the probability of coverage of SUs heavily depend on both the underwater acoustic channel conditions and the activities of PUs.

Impact of Outcome-Based Education on Software Engineering Teaching: a Case Study

Conference
Hong-Ning Dai, Wei Wei, Hao Wang and Tak-Lam Wong
Proceedings of the IEEE International Conference on Teaching, Assessment, and Learning for Engineering (TALE), Hong Kong, 2017
Publication year: 2017

This paper investigates the impact of outcome- based education (OBE) on students’ learning achievement from a software engineering (SE) program. It is not easy to transform an SE curriculum from traditional knowledge-based education (KBE) method to OBE method since it requires us to identify the outcomes clearly and map the outcomes with the expected capabilities of students. We first give a briefing on our SE program and outline the curriculum, then investigate the impact of OBE in two selected courses in SE program, with the completion of one course being the prequisite for admission into the other one. Experimental results show that OBE can greatly improve the learning effectiveness of students and teaching quality.

Friendly-Jamming: An Anti-Eavesdropping Scheme in Wireless Networks

Conference
Xuran Li, Hong-Ning Dai
Proceedings of 18th International Symposium on a World of Wireless, Mobile and Multimedia Networks (WoWMoM), Macau, 2017 (PhD forum Session)
Publication year: 2017

Data-Driven QoE Analysis on Video Streaming in Mobile Networks

Conference
Qingyong Wang, Hong-Ning Dai, Hao Wang and Di Wu
Proceedings of the 15th IEEE International Symposium on Parallel and Distributed Processing with Applications (IEEE ISPA 2017), Guangzhou, China, 2017
Publication year: 2017

There is a substantial body of literature on analyzing Quality of Experience (QoE) of Video Streaming while there are few studies on standardizing QoE assessments. One of recent proposals on standardizing QoE of video streaming is video Mean Opinion Score (vMOS), which can model QoE of video streaming in 5 discrete grades. However, there are few studies on quantifying vMOS and investigating the relation between vMOS and other Quality of Service (QoS) parameters. In this paper, we address this concern by proposing a data-driven QoE analysis framework on video streaming QoE data. Moreover, we conduct extensive experiments on realistic dataset and verify the effectiveness of our proposed model. Our results show that vMOS is essentially affected by many QoS parameters such as initial buffering latency, stalling ratio and stalling times. Interestingly, we have found that a small set of QoS parameters play an important role in determining vMOS.

An overview of Blockchain Technology: Architecture, Consensus, and Future Trends

Conference
Zibin Zheng, Shaoan Xie, Hong-Ning Dai, Xiangping Chen, Huaimin Wang
Proceedings of the 2017 IEEE BigData Congress, Honolulu, Hawaii, USA, 2017
Publication year: 2017

Blockchain, the foundation of Bitcoin, has received extensive attentions recently. Blockchain serves as an immutable ledger which allows transactions take place in a decentralized manner. Blockchain-based applications are springing up, covering numerous fields including financial services, reputation system and Internet of Things (IoT), and so on. However, there are still many challenges of blockchain technology such as scalability and security problems waiting to be overcome. This paper presents a comprehensive overview on blockchain technology. We provide an overview of blockchain architecture firstly and compare some typical consensus algorithms used in different blockchains. Furthermore, technical challenges and recent advances are briefly listed. We also lay out possible future trends for blockchain.

An improved anti-eavesdropping shelter for protection of wireless communication

Patent
Hong-Ning Dai, Xuran Li, Qiu Wang and Athanasios V. Vasilakos
Australian Innovation Patent 2,017,100,336
Publication year: 2017

An improved anti-eavesdropping shelter for protection of wireless communication

Patent
An improved anti-eavesdropping shelter for protection of wireless communication
Hong-Ning Dai, Xuran Li, Qiu Wang and Athanasios V. Vasilakos, US Patent 9,800,367 B1
Publication year: 2017

The present invention relates to methods and apparatus that improve anti-eavesdropping (AE) configurations of friendly jammers that mitigates eavesdropping attacks in wireless networks.

AE-Shelter: An Novel Anti- Eavesdropping Scheme in Wireless Networks

Conference
Xuran Li, Hong-Ning Dai, Qiu Wang, Athanasios V. Vasilakos
Proceedings of IEEE International Conference on Communications (ICC), Paris, France, 2017
Publication year: 2017

To protect confidential communications from eavesdropping attacks in wireless networks, we propose a novel anti-eavesdropping scheme named AE-Shelter. In our proposed scheme, we place a number of friendly jammers at a circular boundary to protect legitimate communications. The jammers sending artificial noise can mitigate the eavesdropping capability of wiretapping the confidential information. We also establish a theoretical model to evaluate the performance of AE-Shelter. Our results show that our proposed AE-Shelter scheme can significantly reduce the eavesdropping risk without significantly degrading the network performance.

A Smart MCDM Framework to Evaluate Impact of Air Pollution on City Sustainability: A Case Study from China

Journal
Qingyong Wang, Hong-Ning Dai, Hao Wang
Sustainability, vol. 9, no. 6
Publication year: 2017

Air pollution has become one of the key environmental concerns in the urban sustainable development. It is important to evaluate the impact of air pollution on socioeconomic development since it is the prerequisite to enforce an effective prevention policy of air pollution. In this paper, we model the impact of air pollution on the urban economic development as a Multiple Criteria Decision Making (MCDM) problem. In particular, we propose a novel Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) analysis framework to evaluate multiple factors of air pollutants and economic development. Our method can overcome the drawbacks of conventional TOPSIS methods by using Bayesian regularization and the Back-Propagation (BP) neural network to optimize the weight training process. We have conducted a case study to evaluate our proposed framework.

Two-Stage Game for Joint Bandwidth and Multiple Homing Relay Allocation in Cooperative D2D Networks

Conference
Long Chen, Jigang Wu, Hong-Ning Dai and Xiaoxia Huang
Proceedings of 18th IEEE International Conference on High Performance Computing and Communications (HPCC 2016), Sydney, Australia
Publication year: 2016

As an emerging technology, Cooperative Device to Device (CD2D) communication has been considered to alleviate capacity shortage problem. In a heterogeneous CD2D network, multiple homing mobile devices (MMDs) may act as relays for the cooperative communication of ordinary mobile devices (OMDs). Under this setting, how to provide incentive mechanisms and motivate MMDs to lease spare bandwidths and allocate OMDs to MMDs should be carefully studied. Meanwhile, the competition dynamics between MMDs should also be taken into account. We formulate the joint bandwidth allocation and relay selection problem as a two-stage game. In the first stage of the game, a non-cooperative game is used to model the competition among the relay MMDs in terms of shared bandwidth and price. The second stage of the game models the behavior of OMDs selecting MMDs by an evolutionary game. We prove the Nash equilibrium of the game. Extensive numerical analysis and simulation results demonstrate effectiveness of the proposed scheme.

Parallelizing Simulated Annealing Algorithm in Many Integrated Core Architecture

Book ChapterConference
Junhao Zhou, Hong Xiao, Hao Wang, Hong-Ning Dai
In: Gervasi O. et al. (eds) Computational Science and Its Applications – ICCSA 2016. ICCSA 2016. Lecture Notes in Computer Science, vol 9787. Springer
Publication year: 2016

The simulated annealing algorithm (SAA) is a well-established approach to the approximate solution of combinatorial optimisation problems. SAA allows for occasional uphill moves in an attempt to reduce the probability of becoming stuck in a poor but locally optimal solution. Previous work showed that SAA can find better solutions, but it takes much longer time. In this paper, in order to harness the power of the very recent hybrid Many Integrated Core Architecture (MIC), we propose a new parallel simulated annealing algorithm customised for MIC. Our experiments with the Travelling Salesman Problem (TSP) show that our parallel SAA gains significant speedup.

On Performance Analysis of Protective Jamming Schemes in Wireless Sensor Networks

Journal
Xuran Li, Hong-Ning Dai, Hao Wang, Hong Xiao
Sensors, vol. 16, no. 12, 2016
Publication year: 2016

Wireless sensor networks (WSNs) play an important role in Cyber Physical Social Sensing (CPSS) systems. An eavesdropping attack is one of the most serious threats to WSNs since it is a prerequisite for other malicious attacks. In this paper, we propose a novel anti-eavesdropping mechanism by introducing friendly jammers to wireless sensor networks (WSNs). In particular, we establish a theoretical framework to evaluate the eavesdropping risk of WSNs with friendly jammers and that of WSNs without jammers. Our theoretical model takes into account various channel conditions such as the path loss and Rayleigh fading, the placement schemes of jammers and the power controlling schemes of jammers. Extensive results show that using jammers in WSNs can effectively reduce the eavesdropping risk. Besides, our results also show that the appropriate placement of jammers and the proper assignment of emitting power of jammers can not only mitigate the eavesdropping risk but also may have no significant impairment to the legitimate communications.

On Modeling Eavesdropping Attacks in Underwater Acoustic Sensor Networks

Journal
Qiu Wang, Hong-Ning Dai, Xuran Li, Hao Wang, Hong Xiao
Sensors, vol. 16, no. 5, 2016
Publication year: 2016

The security and privacy of underwater acoustic sensor networks has received extensive attention recently due to the proliferation of underwater activities. This paper proposes an analytical model to investigate the eavesdropping attacks in underwater acoustic sensor networks. Our analytical framework considers the impacts of various underwater acoustic channel conditions (such as the acoustic signal frequency, spreading factor and wind speed) and different hydrophones (isotropic hydrophones and array hydrophones) in terms of network nodes and eavesdroppers. We also conduct extensive simulations to evaluate the effectiveness and the accuracy of our proposed model. Empirical results show that our proposed model is quite accurate. In addition, our results also imply that the eavesdropping probability heavily depends on both the underwater acoustic channel conditions and the features of hydrophones.

Underwater; Sensor Networks; Security

 

On Local Connectivity of Cognitive Radio Ad Hoc Networks with Directional Antennas

Conference
Yuanyuan Wang, Hong-Ning Dai, Qiu Wang, Haibo Huang, Jianqing Li
Proceedings of the 15th IEEE International Conference on Communication Systems (ICCS), Shenzhen, China, 2016
Publication year: 2016

On Eavesdropping Attacks in Wireless Networks

Conference
Hong-Ning Dai, Hao Wang, Hong Xiao, Xuran Li, Qiu Wang
Proceedings of 14th IEEE/IFIP International Conference on Embedded and Ubiquitous Computing (EUC), Paris, France, 2016
Publication year: 2016

On Channel Allocation of Directional Wireless Networks Using Multiple Channels

Conference
Hong-Ning Dai, Hao Wang, Hong Xiao
Proceedings of 11th International Network Conference (INC), Frankfurt, Germany, 2016
Publication year: 2016

On Analyzing Eavesdropping Behaviours in Underwater Acoustic Sensor Networks

Conference
Hong-Ning Dai, Hao Wang, Hong Xiao, Zibin Zheng, Qiu Wang, Xuran Li, Xu Zhuge
Proceedings of 11th ACM International Conference on Underwater Networks and Systems (WUWNet’16), Shanghai, China
Publication year: 2016

Friendly-Jamming: An Anti-Eavesdropping Scheme in Wireless Nets of Things

Conference
Xuran Li, Hong-Ning Dai, Hao Wang
Proceedings of 2016 IEEE Global Communications Conference (GLOBECOM), Washington D.C. USA, 2016
Publication year: 2016

In this paper, we propose a novel anti-eavesdropping scheme by introducing friendly jammers to a wireless network of things (WNoT). In particular, we establish a theoretical framework to evaluate the eavesdropping risk of WNoT with friendly jammers and the eavesdropping risk of WNoT without jammers. Our theoretical model takes into account various channel conditions such as the path loss and Rayleigh fading as well as the placement schemes of jammers. Our extensive numerical results show that using jammers in WNoT can effectively reduce the eavesdropping risk. Besides, our results also show that the eavesdropping risk heavily depends on both the channel conditions and the placements of jammers.

Internet of Things; Wireless Communications; Jamming Scheme; Security

AT-MAC: A Novel Full Duplex MAC Design for Achieving Asymmetric Transmission

Book ChapterConference
Zhijie Ma, Qinglin Zhao, Yu Zeng, Huan Zhang, Hong-Ning Dai
In: Kim K., Wattanapongsakorn N., Joukov N. (eds) Mobile and Wireless Technologies 2016. Lecture Notes in Electrical Engineering, vol 391. Springer, Singapore
Publication year: 2016

Wireless Full-duplex technique can significantly improve system throughput of a wireless network. Most existing full-duplex-supporting wireless MAC schemes only achieve symmetric transmission (i.e., the uplink throughput of a node is equal to its downlink throughput). However, in reality, the uplink and downlink traffic is often asymmetric. In this paper, we propose a novel MAC scheme called AT-MAC to achieve asymmetric transmission. In AT-MAC, upon receiving a packet, a receiver determines whether to execute a reverse transmission to the peer or to initiate a new transmission to a third node, according to the peer’s uplink and downlink requirements. Extensive simulations verify that the proposed design is feasible and efficient.

APPLE: Providing Absolute and Proportional Throughput Guarantees in Wireless LANs

Conference
Zhijie Ma, Qinglin Zhao, Hong-Ning Dai, Huan Zhang
Proceedings of 18th International Conference on Communications and Computer Networks (ICCCN 2016), Singapore, 2016
Publication year: 2016

An Analytical Study on Eavesdropping Attacks in Wireless Nets of Things

Journal
Xuran Li, Hao Wang, Hong-Ning Dai, Yuanyuan Wang, Qinglin Zhao
Mobile Information Systems, Volume 2016 (2016), Article ID 4313475, 10 pages
Publication year: 2016

The security of Internet of Things (IoT) has received extensive attention recently. This paper presents a novel analytical model to investigate the eavesdropping attacks in Wireless Net of Things (WNoT). Our model considers various channel conditions, including the path loss, the shadow fading effect, and Rayleigh fading effect. Besides, we also consider the eavesdroppers in WNoT equipped with either omnidirectional antennas or directional antennas. Extensive simulation results show that our model is accurate and effective to model the eavesdropping attacks in WNoT. Besides, our results also indicate that the probability of eavesdropping attacks heavily depends on the shadow fading effect, the path loss effect, Rayleigh fading effect, and the antenna models. In particular, we find that the shadow fading effect is beneficial to the eavesdropping attacks while both the path loss effect and Rayleigh fading effect are detrimental. Besides, using directional antennas at eavesdroppers can also increase the eavesdropping probability. Our results offer some useful implications on designing antieavesdropping schemes in WNoT.

A novel hybrid data mining framework for credit evaluation

Book ChapterConference
Yatao Yang, Zibin Zheng, Chunzhen Huang, Kunmin Li, Hong-Ning Dai
In: Wang S., Zhou A. (eds) Collaborate Computing: Networking, Applications and Worksharing. CollaborateCom 2016. Lecture Notes of the Institute for Computer Sciences, Social Informatics and Telecommunications Engineering, vol 201. Springer, Cham
Publication year: 2016

Internet loan business has received extensive attentions recently. How to provide lenders with accurate credit scoring profiles of borrowers becomes a challenge due to the tremendous amount of loan requests and the limited information of borrowers. However, existing approaches are not suitable to Internet loan business due to the unique features of individual credit data. In this paper, we propose a unified data mining framework consisting of feature transformation, feature selection and hybrid model to solve the above challenges. Extensive experiment results on realistic datasets show that our proposed framework is an effective solution.

Peer-to-Pear (P2P) Loan; China; Finance; Internet Loan Business; Data Analytics

 

PPeLE: a Photo-Processing e-Learning Environment based on HTML5

Conference
Jianing Dai, Zheng Zhou, Hao Wang, Hong-Ning Dai
Proceedings of IEEE International Conference on Teaching, Assessment and Learning for Engineering (TALE), Zhuhai, China, 2015
Publication year: 2015

On the Percolation Connectivity of Large Scale Wireless Networks with Directional Antennas

Conference
Hong-Ning Dai, Raymond Chi-Wing Wong, Wei Zhang, Liqun Fu
Proceedings of IEEE 25th International Symposium on Personal, Indoor and Mobile Radio Communications - (PIMRC), Hong Kong, 2015
Publication year: 2015

We investigate the percolation connectivity of wireless ad hoc networks with directional antennas (called DIR networks). One of major concerns is to derive bounds on the number of edge-disjoint directed paths (or highways). However, it is non-trivial to obtain bounds on the number of directed highways in DIR networks since the conventional undirected percolation theory cannot be directly used in DIR networks. In this paper, we exploit the directed percolation theory to derive bounds on the number of directed highways. In particular, we make new constructions in bond directed percolation model. We show that with high probability there are at least Ω(√n/log log √n) directed highways in a network with n nodes, which is much tighter than the existing results in DIR networks.

On the Delay Reduction of Wireless Ad Hoc Networks with Directional Antennas

Journal
Hong-Ning Dai, Qinglin Zhao
EURASIP Journal on Wireless Communications and Networking, Jan. 2015
Publication year: 2015

It is shown that the throughput capacity of wireless ad hoc networks using omni-directional antennas (OMN networks) is significantly decreased with the increased number of nodes. One major reason lies in the interference caused by using omni-directional antennas, which just broadcast radio signal in all directions. Thus, a communication with multipleshort-rangedhops is suggested in such networks to avoid interference and improve the throughput. However, the multi-hop transmission can also significantly increase the end-to-end delay.

In this paper, we investigate the throughput improvement and the delay reduction by using directional antennas in wireless ad hoc networks. We call such wireless ad hoc networks using directional antennas as DIR networks. In particular, we investigate the effective transmission range of directional antennas with consideration of various channel conditions, such as the large scale path loss and the shadow fading effect. We have found that directional antennas can significantly increase the transmission range compared with omni-directional antennas even under the same channel condition. Besides, we derive the throughput and the delay of a DIRnetwork by constructing a routing scheme and a time-division multi-access (TDMA) scheme. We have found that using directional antennas not only can increase the throughput capacity but also can decrease the delay by reducing the number of hops.

On Modeling Eavesdropping Attacks in Wireless Networks

Journal
Xuran Li, Jianlong Xu, Hong-Ning Dai, Qinglin Zhao, Chak Fong Cheang, Qiu Wang
Journal of Computational Science, Vol. 11, Pages 196 - 204, November 2015
Publication year: 2015

This paper concerns the eavesdropping attacks from the eavesdroppers’ perspective, which is new since most of current studies consider the problem from the good nodes’ perspective. In this paper, we originally propose an analytical framework to quantify the effective area and the probability of the eavesdropping attacks. This framework enables us to theoretically evaluate the impact of node density, antenna model, and wireless channel model on the eavesdropping attacks. We verify via extensive simulations that the proposed analytical framework is very accurate. Our results show that the probability of eavesdropping attacks significantly vary, depending on the wireless environments (such as shadow fading effect, node density, and antenna types). This study lays the foundation toward preventing the eavesdropping attacks in more effective and more economical ways.

Local Connectivity of Wireless Networks with Directional Antennas

Conference
Yuanyuan Wang, Hong-Ning Dai, QiuWang, Xuran Li, Qinglin Zhao, Chak Fong Cheang
Proceedings of IEEE 25th International Symposium on Personal, Indoor and Mobile Radio Communications - (PIMRC), Hong Kong, 2015
Publication year: 2015

This paper concerns with the local connectivity (i.e., the probability of node isolation) of wireless networks with directional antennas. We propose an analytical framework to study the local connectivity with the consideration of directional antenna models and various channel conditions. With the framework, we construct a novel directional antenna model called Iris. We show that Iris can better approximate realistic directional antennas and can be easily used to analyze the local connectivity compared with existing directional antenna models. Extensive simulations show that the theoretical results are in good agreement with the simulation results verifying the accuracy and the effectiveness of our analytical framework.

Eavesdropping Attacks in Underwater Acoustic Networks

Conference
QiuWang, Hong-Ning Dai, Xuran Li, Hao Wang
In Proceedings of the 10th International Conference on Information, Communications and Signal Processing (ICICS), Singapore, 2015
Publication year: 2015

This paper investigates the eavesdropping attacks in underwater acoustic networks (UANets). In particular, we propose an analytical framework to model the eavesdropping attacks in UANets in terms of the eavesdropping probability. Results of extensive simulations match the analytical results, indicating the effectiveness and accuracy of our model. Besides, we also find that the eavesdropping probability in UANets heavily depends on the underwater acoustic channel characterizing by the acoustic signal frequency, the spreading factor and the distance between the transmitter and the eavesdropper. This study provides useful insights that will help us to design anti-eavesdropping schemes with a better protection on the confidential communications.

Eavesdropping Activities in Wireless Networks: Impact of Channel Randomness

Conference
Xuran Li, Hong-Ning Dai, Yuanyuan Wang, Hao Wang
Proceedings of IEEE Region 10 Conference (TENCON), Macau, 2015
Publication year: 2015

Big Data and Industrial Internet of Things for the Maritime Industry in Northwestern Norway

Conference
Hao Wang, Ottar Osen, Guoyuan Li, Wei Li, Hong-Ning Dai, Wei Zeng
Proceedings of IEEE Region 10 Conference (TENCON), Macau, 2015
Publication year: 2015

Big Data Analytics (BDA) and Internet of Things (IoT) are rising quickly. The recent emerging Industrial IoT (IIoT), a sub-paradigm of IoT, focuses more in safety-critical industrial applications. Studies showed that the adoption of BDA increase companies’ output and productivity; IoT enables companies to have more information and control in physical resources, processes, and environments; BDA and IIoT complement each other and develop as a double “helix”. In this position paper, we briefly review the opportunities and challenges in this era of big data and IoT for the Møre maritime cluster; then we propose a new framework integrating BDA and IIoT technologies for offshore support vessels (OSVs) based on a hybrid CPU/GPU/FPGA1 high performance computing platform. We believe that such a framework, when implemented, can help maritime companies increase their output and productivity, and hence enable the whole cluster to continue to be a leader in the global maritime industry.

A weighted T2F scheme for WLANs

Book ChapterConference
Huan Zhang, Qinglin Zhao, Pei Dang, Hong-Ning Dai, Zhijie Ma
Zhang H., Zhao Q., Dang P., Dai H., Ma Z. (2015) A Weighted T2F Scheme for WLANs. In: Kim K., Wattanapongsakorn N. (eds) Mobile and Wireless Technology 2015. Lecture Notes in Electrical Engineering, vol 310. Springer, Berlin, Heidelberg
Publication year: 2015

WiFi network is known to be wasteful because WiFi performs the time-domain contention and often forces channel to remain idle. The time to frequency (T2F) protocol has recently been proposed to perform the frequency-domain contention and it has shown that T2F can reduce the contention overheads effectively. However, T2F just provides fair channel access. In this paper, we proposed a novel weighted T2F (WT2F) design that can provide weighted channel access. We then study the proportional fairness of WT2F. Simulation results validate that the proposed design is very effective and the proposed performance model is very accurate.

A Novel OFDM-Based MAC Protocol for Wireless LANs

Conference
Fangxin Xu, Qinglin Zhao, Yu Zeng, Jie Yang, Hong-Ning Dai, Pei Dang
Proceedings of The 10th International Conference on Communications and Network- ing in China, Shanghai, China, 2015
Publication year: 2015

SPTF: Smart Photo-Tagging Framework on Smart Phones

Journal
Hao Xu, Hong-Ning Dai, Walter Hon-Wai Lau
International Journal of Multimedia and Ubiquitous Engineering (IJMUE), Vol.9, No.9, 2014
Publication year: 2014

Smart phones, as one of the most important platforms for personal communications and mobile computing, have evolved with various embedded devices, such as cameras, Wi-Fi transceivers, Bluetooth transceivers and sensors. Specifically, the photos taken by a smart phone has the approximate or even equivalent image quality to that of a professional camera. As a result, smart phones have become the first choice for people to take photos to record their ordinary life. However, how to manage thousands of photos on a smart phone becomes a challenge. In this paper, we propose a new architecture in terms of Smart Photo-Tagging Framework (SPTF) to manage the substantial number of photos taken by smart phones. In particular, our SPTF collects the ambient data obtained from various embedded sensors on a smart phone when a photo is taken. After processing and analyzing the ambient data, SPTF can accurately record both the ambient tags and the face tags of the photo, which will be used for auto-tagging photos and searching photos. We also implement SPTF and verify its effectiveness by conducting a number of realistic experiments.

Multi-channel Wireless Networks with Infrastructure Support: Capacity and Delay

Conference
Hong-Ning Dai, Raymond Chi-Wing Wong, Qinglin Zhao
Proceedings of IEEE International Conference on Communications (ICC), Sydney, Australia, 2014
Publication year: 2014

In this paper, we propose a novel multi-channel wireless network with infrastructure support, called an MC-IS network. To the best of our knowledge, we are the first to study the capacity and the delay of such an MC-IS network. In particular, we derive the upper bounds and the lower bounds on the network capacity of such MC-IS networks contributed by ad hoc communications, where the orders of the upper bounds are the same as the orders of the lower bounds, implying that the bounds are tight. We also found that the capacity of MC-IS networks contributed by ad hoc communications is mainly limited by connectivity requirement, interference requirement, destination-bottleneck requirement and interface-bottleneck requirement. In addition, we also derive the average delay of MC-IS networks contributed by ad hoc communications, which is bounded by the maximum number of hops.

Eavesdropping Attacks in Wireless Ad Hoc Networks under a Shadow Fading Environment

Conference
Xuran Li, Hong-Ning Dai, Qinglin Zhao, Qiu Wang
Proceedings of International Conference on Internet of Vehicles (IOV), Beijing, China, 2014
Publication year: 2014

An Analytical Model on Eavesdropping Attacks in Wireless Networks

Conference
Xuran Li, Hong-Ning Dai, Qinglin Zhao
Proceedings of IEEE International Conference on Communication Systems (ICCS), Macau, 2014
Publication year: 2014

Performance Evaluation of the Delayed-DCF Scheme in Wireless LANs

Journal
Qinglin Zhao, Zhijie Ma, Hong-Ning Dai
International Journal of Future Computer and Communication (IJFCC), Vol. 2, No. 5, October 2013
Publication year: 2013

Performance Evaluation of the Delayed-DCF Scheme in Wireless LANs

Conference
Qinglin Zhao, Zhijie Ma, Hong-Ning Dai
International Conference on Network and Computer Science (ICNCS), Singapore, 2013
Publication year: 2013

long version appears in International Journal of Future Computer and Communication (IJFCC), Vol. 2, No. 5, October 2013

On Eavesdropping Attacks in Wireless Sensor Networks with Directional Antennas

Journal
Hong-Ning Dai, Qiu Wang, Dong Li, Raymond Chi-Wing Wong
International Journal of Distributed Sensor Networks, Vol. 2013
Publication year: 2013

The eavesdropping attack is a serious security threat to a wireless sensor network (WSN) since the eavesdropping attack is a prerequisite for other attacks. Conventional WSNs consist of wireless nodes equipped with omnidirectional antennas, which broadcast radio signals in all directions and are consequently prone to the eavesdropping attacks. Different from omnidirectional antennas, directional antennas radiate radio signals on desired directions and potentially reduce the possibility of the eavesdropping attacks. In this paper, we propose a model to analyze the eavesdropping probability in both single-hop WSNs and multihop WSNs with omnidirectional antennas and directional antennas. We verify the correctness of our analytical model by conducting extensive simulations. We have found that using directional antennas in either single-hop WSNs or multihop WSNs can significantly reduce the eavesdropping probability. The reason of the improved security of WSNs with directional antennas lies in (i) the smaller exposure region of a directional antenna and (ii) the fewer hops to route a packet due to the longer transmission range of a directional antenna. Our results have also shown that the security improvement factor heavily depends on the node density, the antenna beamwidth, and the signal path loss factor.

On Busy-Tone based MAC Protocol for Wireless Networks with Directional Antennas

Journal
Hong-Ning Dai, Kam-Wing Ng, Min-You Wu
Wireless Personal Communications, Vol. 73, Issue 3, pp. 611 - 636, 2013
Publication year: 2013

The application of directional antennas in wireless ad hoc networks offers numerous benefits, such as the extended communication range, the increased spatial reuse, the improved capacity and the suppressed interference. However, directional antennas can cause new location-dependent carrier sensing problems, such as new hidden terminal and deafness problems, which can severely degrade the network performance. Recently, a few schemes have been proposed to address these problems. However, most of these existing methods can only partially solve the hidden terminal and deafness problems. Some of them even bring significant performance overhead. In this paper, we propose a novel MAC protocol, in terms of the busy-tone based directional medium access control (BT-DMAC) protocol. In BT-DMAC, when the transmission is in progress, the sender and the receiver will turn on their omni-directional busy tones to protect the on-going transmission. Integrating with the directional network allocation vector (DNAV), the scheme can almost mitigate the hidden terminal problem and the deafness problem completely. We then propose an analytical model to investigate the throughput performance of BT-DMAC. The numerical results show that BT-DMAC outperforms other existing directional MAC schemes. We next evaluate the performance of BT-DMAC through extensive simulation experiments. The results show that our proposed BT-DMAC scheme has superior performance to other existing solutions, in terms of higher throughput.

New Techniques to Improve the Throughput Efficiency in Wireless LANs

Conference
Qinglin Zhao, Hong-Ning Dai
Proceedings of International Research Conference on Information Technology and Computer Sciences, Kuala Lumpur, Malaysia, 2013
Publication year: 2013

Eavesdropping Security in Wireless Ad Hoc Networks with Directional Antennas

Conference
Qiu Wang, Hong-Ning Dai, Qinglin Zhao
Proceedings of The 22nd Wireless and Optical Communications Conference (WOCC), Chongqing, China, 2013
Publication year: 2013

Connectivity of Wireless Ad Hoc Networks: Impacts of Antenna Models

Conference
Qiu Wang, Hong-Ning Dai, Qinglin Zhao
Proceedings of International Conference on Parallel and Distributed Computing, Applications and Technologies (PDCAT), Taipei, Taiwan, 2013
Publication year: 2013

Channel Allocation in Wireless Networks with Directional Antennas

Journal
Hong-Ning Dai, Kam-Wing Ng, Min-You Wu
Journal of Sensor and Actuator Networks, 2(2), pp. 213 - 234, 2013
Publication year: 2013

In this paper, we study the channel allocation in multi-channel wireless ad hoc networks with directional antennas. In particular, we investigate the problem: given a set of wireless nodes equipped with directional antennas, how many channels are needed to ensure collision-free communications? We derive the upper bounds on the number of channels, which heavily depend on the node density and the interference ratio (i.e., the ratio of the interference range to the transmission range). We construct several scenarios to examine the tightness of the derived bounds. We also take the side-lobes and back-lobes as well as the signal path loss into our analysis. Our results can be used to estimate the number of channels required for a practical wireless network (e.g., wireless sensor network) with directional antennas.

An Overview of Using Directional Antennas in Wireless Networks

Journal
Hong-Ning Dai, Kam-Wing Ng, Minglu Li, Min-You Wu
Vol. 26, Issue 4, pp. 413 - 448, 2013
Publication year: 2013

Compared with omni-directional antennas, directional antennas have many merits, such as lower interference, better spatial reuse, longer transmission range, and improved network capacity. Directional antennas enable numerous emerging outdoor and indoor applications, which have been addressed in many recent studies. Despite the advances in wireless networks with directional antennas (DAWNs), there are many research challenges in all layers of DAWNs. This paper presents a detailed study on recent advances and open research issues on DAWNs. Firstly, we briefly introduce the classification of directional antennas, antenna radiation patterns, antenna modes, and the challenges in the physical layer of DAWNs. We then present research issues on the medium access control (MAC) layer, followed by the current solutions as well as open research problems on the MAC layer of DAWNs. In addition, we also discuss the research issues on the routing layer and the transport layer. Moreover, other research challenges on the performance evaluation of DAWNs and a brief introduction of indoor DAWNs are given in this paper as well. In conclusion, we summarize the current research issues on DAWNs as well as prospects in the future.

On the Connectivity of Wireless Networks with Multiple Directional Antennas

Conference
Huiwen Xu, Hong-Ning Dai, Qinglin Zhao
Proceedings of IEEE International Conference on Networks (ICON), Singapore, 2012
Publication year: 2012

The network connectivity is one of important measures of the performance of wireless networks. However, most of current studies on the network connectivity only consider either an SOMN network, where each node is mounted with a single omni-directional antenna, or an SDA network, where each node is mounted with a single directional antenna. Using multiple directional antennas instead of a single directional antenna can potentially improve the network performance. In this paper, we investigate the connectivity of a novel network, in terms of an MDA network, where each node is mounted with multiple directional antennas. We found that MDA networks have much stronger network connectivity than other existing networks (such as SOMN and SDA networks), and its connectivity degree heavily depends on the number of antennas, the beamwidth of each antenna and the path loss factor. The enhancement mainly owes to the usage of multiple antennas and the longer transmission range of directional antennas.

MAC Enhancements for Wireless LANs

Conference
Qingling Zhao, Hong-Ning Dai, Gang Tu
Proceedings of the 8th International Conference on Networked Computing (INC), Gyeongju, Korea, 2012
Publication year: 2012

Link Scheduling in Multi-Transmit-Receive Wireless Networks

Conference
Hong-Ning Dai, Soung Chang Liew, Liqun Fu
Proceedings of the 36th IEEE Conference on Local Computer Networks (LCN), Bonn, Germany, 2011
Publication year: 2011

This paper investigates the problem of link scheduling to meet traffic demands with minimum airtime in a multi-transmit-receive (MTR) wireless network. MTR networks are a new class of networks, in which each node can simultaneously transmit to a number of other nodes, or simultaneously receive from a number of other nodes. The MTR capability can be enabled by the use of multiple directional antennas or multiple channels. Potentially, MTR can boost the network capacity significantly. However, link scheduling that makes full use of the MTR capability must be in place before this can happen. We show that optimal link scheduling can be formulated as a linear program (LP). However, the problem is NP-hard because we need to find all the maximal independent sets in a graph first. We propose two computationally efficient algorithms, called Heavy-Weight-First (HWF) and Max-Degree-First (MDF) to solve this problem. Simulation results show that both HWF and MDF can achieve superior performance in terms of runtime and optimality.

Exploring Security Improvement of Wireless Networks with Directional Antennas

Conference
Hong-Ning Dai, Dong Li, Raymond Chi-Wing Wong
Proceedings of the 36th IEEE Conference on Local Computer Networks (LCN), Bonn, Germany, 2011
Publication year: 2011

There are a number of studies on using directional antennas in wireless networks. Many of them concentrate on analyzing the theoretical capacity improvement by using directional antennas. Other studies focus on designing proper Medium Access Control (MAC) protocols to improve the practical network throughput. There are few works on the security improvement using directional antennas. In this paper, we explore the benefits of directional antennas in security improvements on both single-hop and multi-hop wireless networks. In particular, we found that using directional antennas in wireless networks can significantly reduce the eavesdropping probabilities of both single-hop transmissions as well as multi-hop transmissions and consequently improve the network security.

Upper Bounds on the Number of Channels to Ensure Collision-free Communications in Multi-Channel Wireless Networks Using Directional Antennas

Conference
Hong-Ning Dai, Kam-Wing Ng, Min-You Wu
Proceedings of Wireless Communications and Networking Conference (IEEE WCNC) 2010, Sydney, Australia
Publication year: 2010

Throughput and Delay in Wireless Sensor Networks using Directional Antennas

Conference
Hong-Ning Dai
Proceedings of the Fifth International Conference on Intelligent Sensors, Sensor Networks and Information Processing (IEEE ISSNIP) 2009, Melbourne, Australia
Publication year: 2009

Most of studies only consider that wireless sensor networks are equipped with only omni-directional antennas, which can cause high collisions. It is shown that the per node throughput in such networks is decreased with the increased number of nodes. Thus, the transmission with multiple short-range hops is preferred to reduce the interference. However, other studies show that the transmission delay increases with the increased number of hops. In this paper, we consider using directional antennas in wireless sensor networks. We have found that using directional antennas not only can increase the throughput capacity but also can decrease the delay by reducing the number of hops. We also construct a time-division multi-access (TDMA) scheme to achieve this. Compared with omni-directional antennas, directional antennas can reduce the interference and lead to the improvement on the network capacity. Furthermore, directional antennas can extend the transmission range, which leads to fewer hops and the lower multi-hop routing delay.

On the Capacity of Multi-Channel Wireless Networks Using Directional Antennas

Conference
Hong-Ning Dai, Kam-Wing Ng, Raymond Chi-Wing Wong, Min-You Wu
Proceedings of the 27th IEEE Conference on Computer Communications (IEEE INFOCOM) 2008, Phoenix, USA
Publication year: 2008

The capacity of wireless ad hoc networks is affected by two key factors: the interference among concurrent transmissions and the number of simultaneous transmissions on a single interface. Recent studies found that using multiple channels can separate concurrent transmissions and greatly improve network throughput. However, those studies only consider that wireless nodes are equipped with only omnidirectional antennas, which cause high collisions. On the other hand, some researchers found that directional antennas bring more benefits such as reduced interference and increased spatial reuse compared with omnidirectional antennas. But, they only focused on a single-channel network which only allows finite concurrent transmissions. Thus, combining the two technologies of multiple channels and directional antennas together potentially brings more benefits. In this paper, we propose a multi-channel network architecture (called MC-MDA) that equips each wireless node with multiple directional antennas. We derive the capacity bounds of MC-MDA networks under arbitrary and random placements. We will show that deploying directional antennas to multi-channel networks can greatly improve the network capacity due to increased network connectivity and reduced interference. We have also found that even a multi-channel network with a single directional antenna only at each node can give a significant improvement on the throughput capacity. Besides, using multiple channels mitigates interference caused by directional antennas. MC-MDA networks integrate benefits from multi-channel and directional antennas and thus have significant performance improvement.

On Collision-Tolerant Transmission with Directional Antennas

Conference
Hong-Ning Dai, Kam-Wing Ng, Min-You Wu
Proceedings of EEE Wireless Communications and Networking Conference (IEEE WCNC) 2008, Las Vegas, USA
Publication year: 2008

The application of directional antennas in wireless ad hoc networks brings numerous benefits, such as increased spatial reuse and mitigated interferences. Most MAC protocols with directional antennas are based on the RTS/CTS mechanism which works well in wireless ad hoc networks using omnidirectional antennas. However, RTS/CTS frames cannot mitigate the interference completely. Besides, they also contribute a lot to the performance overhead. This paper studies the problem from a new perspective. We have found that the transmission success probability under directional transmission and directional reception is quite high when the antenna beamwidth is quite narrow. Motivated by the analytical results, we design a lightweight MAC protocol without RTS/CTS frames. The preliminary results demonstrate that this new protocol performs better than MAC protocols based on the RTS/CTS mechanism. The results also show that a collision-tolerant transmission is feasible under the narrow beam configuration.

Collision-Tolerant Transmission with Narrow-beam Antennas

Journal
Hong-Ning Dai, Kam-Wing Ng, Min-You Wu, Bo Li
International Journal of Communications, Network and System Sciences, Vol. 1, No. 4 (Nov. 2008)
Publication year: 2008

The application of directional antennas in wireless ad hoc networks brings numerous benefits, such as increased spatial reuse and mitigated interference. Most MAC protocols with directional antennas are based on the RTS/CTS mechanism which works well in wireless ad hoc networks using omni-directional antennas. However, RTS/CTS frames cannot mitigate the interference completely. Besides, they also contribute a lot to the performance overhead. This paper studies the problem from a new perspective. We have found that the transmission success probability under directional transmission and directional reception is quite high when the antenna beamwidth is quite narrow. Motivated by the analytical results, we design a lightweight MAC protocol without RTS/CTS frames. The evaluation results demonstrate that this new protocol performs better than MAC protocols based on the RTS/CTS mechanism. The results also show that a collision-tolerant transmission is feasible under the narrow beam configuration.

A Busy-Tone based MAC Scheme for Wireless Ad Hoc Networks using Directional Antennas

Conference
Hong-Ning Dai, Kam-Wing Ng, Min-You Wu
Proceedings of the 50th Annual IEEE Global Telecommunications Conference (IEEE GLOBECOM) 2007, Washington D.C., USA
Publication year: 2007

Applying directional antennas in wireless ad hoc networks offers numerous benefits, such as extended communication range, increased spatial reuse, improved capacity and suppressed interference. However, directional antennas can cause new location-dependent carrier sensing problems, such as new hidden terminal and deafness problems, which can cause severe penalties to the performance. Recently, a few schemes have been proposed to tackle these problems. However, these methods can provide limited solutions on the hidden terminal and deafness problems. We propose a new MAC protocol, termed the busy-tone based directional medium access control (BT-DMAC) protocol. When the transmission is in progress, the sender and the receiver will turn on their omnidirectional busy tones to protect the transmission. By combining with directional network allocation vector (DNAV), the scheme almost mitigates the hidden and the deafness problems completely. The mechanism increases the probability of successful data transmission and consequently improves the network throughput. This paper describes the BT- DMAC scheme and analyzes its performance. The simulation results also demonstrate the effectiveness of the protocol.

An Overview of MAC Protocols with Directional Antennas inWireless ad hoc Networks

Conference
Hong-Ning Dai, Kam-Wing Ng, Min-You Wu
Proceedings of International Conference on Wireless and Mobile Communications (ICWMC) 2006, Bucharest, Romania, July 29-31, 2006
Publication year: 2006

Although directional antennas have been used in mobile communications systems for quite a long time, realistic applications of directional or smart antennas in wireless ad hoc network have emerged just in recent years. Directional antennas provide numerous benefits, such as higher gains, increased transmission range and low interferences. Wireless medium access schemes play a crucial role in ensuring the efficient and fair sharing of wireless resources. Therefore there are many research work on mechanisms at the wireless medium access layer by using directional antennas. The new features of MAC with directional antennas can cause not only location dependent carrier sensing problems, which have appeared in omnidirectional wireless networks, but also novel issues related to directional antennas. In this paper, an introduction of directional antennas is given. We give a classification of the current wireless MAC protocols using directional antennas. We also present different MAC protocols and compare them. This survey discusses the challenges in the design of these MAC protocols.

GRAMS: A Grid Resource Analysis and Monitoring System

Book ChapterConference
Hong-Ning Dai, Minglu Li, Linpeng Huang, Yi Wang, Feng Hong
Lecture Notes in Comput. Sci. Springer-Verlag, Vol. 3516, pp. 875 - 878, 2005
Publication year: 2005

In this paper we propose GRAMS, a resource monitoring and analysis system in Grid environment. GRAMS provides an infrastructure for conducting online monitoring and performance analysis of a variety of Grid resources including computational and network devices. Based on analysis on real-time event data as well as historical performance data, steering strategies are given for users or resource scheduler to control the resources. Besides, GRAMS also provides a set of management tools and services portals for user not only to access performance data but also to handle these resources.

A Visual Editor System for Non-structured Data

Journal
Hong-Ning Dai, GuihuaWen, Yuehua Ding, Chonggui Fan
Research of Computer Application, June 2003
Publication year: 2003

Analyses of the Tree-decomposable Reminding Process

Journal
GuihuaWen, Hong-Ning Dai, Weiqiang Guo
Journal of South China University of Technology (Natural Science Edition), Vol.30, No.5, 2002
Publication year: 2002

A Framework for Product Creative Design Platform

Journal
Guihua Wen, Yuehua Ding, Hong-Ning Dai, Weiping Tu
Mechanical and Electronics Engineering, Vol.31, No.6, 2002
Publication year: 2002

Creative Oriented Database Management System

Conference
Hong-Ning Dai, GuihuaWen, Yuehua Ding
Proceedings of Postgraduate Research Symposium on Computer Science South China University of Technology, Guangzhou, China, Nov. 8, 2001
Publication year: 2001

A Conceptual Hyper-graphModel for Creative Design

Conference
GuihuaWen, Hong-Ning Dai, Yuehua Ding
Proceedings of the 9th Conference of China Association of Artificial Intelligence, Beijing, China, Sept. 9, 2001
Publication year: 2001