Block-Based Projection Matrix Design for Compressed Sensing

Li Zhetao,Xie Jingxiong,Zhu Gengming,Peng Xin,Xie Yanrong,Choi Youngjune IET on behalf of the CIE 2016 Chinese journal of electronics Vol.25 No.3

<P>The objective of optimizing a projection matrix is to decrease the mutual coherence between a projection matrix and a basis matrix. In this paper, a novel block-based method is proposed to design a projection matrix in compressed sensing. Here, the projection matrix is divided into two blocks. The relationship between the two blocks was obtained by reasoning and proving. Theoretical analysis demonstrates that the mutual coherence between the whole projection matrix and the whole basis matrix keeps as good as the mutual coherence between the block matrix and blocked basis matrix. Experimental results show that the proposed method obtains better performance compared to existing methods.</P>

Electricity Cost Minimization for Delay-tolerant Basestation Powered by Heterogeneous Energy Source

( Qingyong Deng ),( Xueming Li ),( Zhetao Li ),( Anfeng Liu ),( Young-june Choi ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.12

Recently, there are many studies, that considering green wireless cellular networks, have taken the energy consumption of the base station (BS) into consideration. In this work, we first introduce an energy consumption model of multi-mode sharing BS powered by multiple energy sources including renewable energy, local storage and power grid. Then communication load requests of the BS are transformed to energy demand queues, and battery energy level and worst-case delay constraints are considered into the virtual queue to ensure the network QoS when our objective is to minimize the long term electricity cost of BSs. Lyapunov optimization method is applied to work out the optimization objective without knowing the future information of the communication load, real-time electricity market price and renewable energy availability. Finally, linear programming is used, and the corresponding energy efficient scheduling policy is obtained. The performance analysis of our proposed online algorithm based on real-world traces demonstrates that it can greatly reduce one day’s electricity cost of individual BS.

Dynamic Spectrum Sharing for Hybrid Access in OFDMA-Based Cognitive Femtocell Networks

Deng, Qingyong,Li, Zhetao,Chen, Jiabei,Zeng, Fanzi,Wang, Hui-Ming,Zhou, Liang,Choi, Young-June IEEE 2018 IEEE Transactions on Vehicular Technology VT Vol.67 No.11

<P>Cognitive femtocell has emerged as one of the promising ways to solve the indoor coverage and spectrum shortage problems in cellular networks. However, it is a challenge to motivate both macro base station ( <TEX>$\text{MBS}$</TEX>) and femtocell access points ( <TEX>$\text{FAPs}$</TEX>) to adopt this hybrid access policy. In this paper, we propose a systematic dynamic spectrum sharing framework for hybrid access in orthogonal frequency-division multiple-access-based cognitive macro-femtocell networks. In this framework, the <TEX>$\text{MBS}$</TEX> offloads some macro user equipments ( <TEX>$\text{MUEs}$</TEX>) to <TEX>$\text{FAP}$</TEX> to improve the transmission performance and save energy. In return, the MBS leases a portion of its spectrum to <TEX>$\text{FAP}$</TEX>. Then, the <TEX>$\text{FAP}$</TEX> can use a part of spectrum for its own transmission and use another part to serve <TEX>$\text{MUEs}$</TEX>. We design an auction-based approach where each <TEX>$\text{FAP}$</TEX> receives additional <TEX>$\text{MUE}$</TEX> as bidders, while MBS acts as auctioneer. We formulate the dynamic resource sharing as a sum utility maximization problem. Numerical results demonstrate that both the macro and femtocell could get benefit from our framework.</P>

Alternative Multiplicative Iterative Method for Projection Matrix Design in Compressive Images

Tian Shujuan,Fan Xiaoping,Xie Jingxiong,Li Zhetao,Choi Youngjune,Sekiya Hiroo 보안공학연구지원센터 2016 International Journal of Signal Processing, Image Vol.9 No.9

A Trust-Based Model for Security Cooperating in Vehicular Cloud Computing

Tang, Zhipeng,Liu, Anfeng,Li, Zhetao,Choi, Young-june,Sekiya, Hiroo,Li, Jie Hindawi Limited 2016 Mobile information systems Vol.2016 No.-

<P>VCC is a computing paradigm which consists of vehicles cooperating with each other to realize a lot of practical applications, such as delivering packages. Security cooperation is a fundamental research topic in Vehicular Cloud Computing (VCC). Because of the existence of malicious vehicles, the security cooperation has become a challenging issue in VCC. In this paper, a trust-based model for security cooperating, named DBTEC, is proposed to promote vehicles’ security cooperation in VCC. DBTEC combines the indirect trust estimation in Public board and the direct trust estimation in Private board to compute the trust value of vehicles when choosing cooperative partners; a trustworthy cooperation path generating scheme is proposed to ensure the safety of cooperation and increase the cooperation completion rates in VCC. Extensive experiments show that our scheme improves the overall cooperation completion rates by 6~7%.</P>

Object tracking based on adaptive updating of a spatial-temporal context model

( Wanli Feng ),( Yigang Cen ),( Xianyou Zeng ),( Zhetao Li ),( Ming Zeng ),( Viacheslav Voronin ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.11

Recently, a tracking algorithm called the spatial-temporal context model has been proposed to locate a target by using the contextual information around the target. This model has achieved excellent results when the target undergoes slight occlusion and appearance changes. However, the target location in the current frame is based on the location in the previous frame, which will lead to failure in the presence of fast motion because of the lack of a prediction mechanism. In addition, the spatial context model is updated frame by frame, which will undoubtedly result in drift once the target is occluded continuously. This paper proposes two improvements to solve the above two problems: First, four possible positions of the target in the current frame are predicted based on the displacement between the previous two frames, and then, we calculate four confidence maps at these four positions; the target position is located at the position that corresponds to the maximum value. Second, we propose a target reliability criterion and design an adaptive threshold to regulate the updating speed of the model. Specifically, we stop updating the model when the reliability is lower than the threshold. Experimental results show that the proposed algorithm achieves better tracking results than traditional STC and other algorithms.

APMD: A fast data transmission protocol with reliability guarantee for pervasive sensing data communication

Liu, Yuxin,Liu, Anfeng,Li, Yuxuan,Li, Zhetao,Choi, Young-june,Sekiya, Hiroo,Li, Jie Elsevier 2017 Pervasive and mobile computing Vol.41 No.-

<P><B>Abstract</B></P> <P>In pervasive sensing data communication systems, it is significant to ensure data reliably and rapidly sent to the control center. Otherwise, laggard data transmission may result in vital loss. An adaptive persistent m data (APMD) transmission protocol is proposed to reduce delay with reliability guarantee for pervasive sensing data communication systems. In APMD transmission protocol, each data packet is sent for m ( m ≥ 1 ) times by sender at the first time of transmission. If the data packet cannot be received successfully for m times, sender will transmit this data packet again and wait for ACK sent back by receiver in the send and wait way. The next data packet will not be sent until this packet is sent successfully or the time of transmission reaches the maximum limit. The option of appropriate value of m is based on the energy situation, which guarantees high network lifetime. Both theoretical analysis and experimental simulation results indicate that the APMD protocol is better than the previous data transmission protocol. The delay can be reduced by 12.73%–14.78%, the energy utilization rate can be improved by about 35% compared to the SW-ARQ protocol, while the reliability increases slightly and the lifetime has no difference.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A fast data transmission protocol is proposed for pervasive sensing. </LI> <LI> The high reliability can be guaranteed in our protocol. </LI> <LI> The delay can be reduced by 12.73%–14.78% compare to previous studies in our protocol. </LI> <LI> The energy utilization can be enhanced by 35%. </LI> </UL> </P>

A green and reliable communication modeling for industrial internet of things

Liu, Anfeng,Zhang, Qi,Li, Zhetao,Choi, Young-june,Li, Jie,Komuro, Nobuyoshi Elsevier 2017 Computers & electrical engineering Vol.58 No.-

<P>Green and reliable communication has great significance for Industrial Internet of Things. Unfortunately, because of the loss nature, achieving reliable transmission is challenging. In this paper, a novel hybrid transmission protocol (HTP) is proposed to maximize lifetime while the reliability is still guaranteed. The proposed protocol adopts Send-Wait automatic Repeat-Request protocol in hotspot areas to reduce the energy consumption and network coding based redundant transmission approach with adaptive redundancy level in non-hotspot areas to guarantee the reliability. The proposed protocol could improve the lifetime and shorten the delay on the premise of ensuring the reliability. Comparing with Send-Wait automatic Repeat-Request protocol, it can improve lifetime by 15%-30% under the same reliability and improve the reliability by 12%-45% under the same lifetime. Comparing with network coding based redundant transmission approach, the lifetime has increased by more than one time under the same reliability. (C) 2016 Elsevier Ltd. All rights reserved.</P>

Generalized analytical expressions for end-to-end throughput of IEEE 802.11 string-topology multi-hop networks

Sanada, Kosuke,Komuro, Nobuyoshi,Li, Zhetao,Pei, Tingrui,Choi, Young-June,Sekiya, Hiroo Elsevier 2018 AD HOC NETWORKS Vol.70 No.-

<P><B>Abstract</B></P> <P>It is an effective approach for comprehending network performance is to develop a mathematical model because complex relationship between system parameters and performance can be obtained explicitly. This paper presents generalized analytical expressions for end-to-end throughput of IEEE 802.11 string-topology multi-hop networks. For obtaining expressions, a relationship between the durations of the backoff-timer (BT) decrements and frame transmission is expressed by integrating modified Bianchi’s Markov-chain model and airtime expression. Additionally, the buffer queueing of each node is expressed by applying the queueing theory. The analytical expressions obtained in this paper provide end-to-end throughput for any hop number, any frame length, and any offered load, including most of analytical expressions presented in previous papers. The analytical results agree with simulation results quantitatively, which shows the verifications of the analytical expressions.</P>

Energy-Efficient Broadcasting Scheme for Smart Industrial Wireless Sensor Networks

Chen, Zhuangbin,Liu, Anfeng,Li, Zhetao,Choi, Young-June,Sekiya, Hiroo,Li, Jie Hindawi Limited 2017 Mobile information systems Vol.2017 No.-

<P>In smart Industrial Wireless Sensor Networks (IWSNs), sensor nodes usually adopt a programmable technology. These smart devices can obtain new or special functions by reprogramming: they upgrade their soft systems through receiving new version of program codes. If sensor nodes need to be upgraded, the sink node will propagate program code packets to them through “one-to-many” broadcasting, and therefore new capabilities can be obtained, forming the so-called Software Defined Network (SDN). However, due to the high volume of code packet, the constraint energy of sensor node, and the unreliable link quality of wireless network, rapidly broadcasting the code packets to all nodes in network can be a challenge issue. In this paper, a novel Energy-efficient Broadcast scheme with adjustable broadcasting radius is proposed aiming to improve the performance of network upgrade. In our scheme, the nonhotspots sensor nodes take full advantage of their residual energy caused in data collection period to improve the packet reception probability and reduce the broadcasting delay of code packet transmission by enlarging the broadcasting radius, that is, the transmitting power. The theoretical analyses and experimental results show that, compared with previous work, our approach can averagely reduce the Network Upgrade Delay (NUD) by 14.8%-45.2% and simultaneously increase the reliability without harming the lifetime of network.</P>