Block-Based Scheme for Database Integrity Verification

Lancine Camara,Junyi Li,Renfa Li,Faustin Kagorora,Damien Hanyurwimfura 보안공학연구지원센터 2014 International Journal of Security and Its Applicat Vol.8 No.6

Databases play an important role today in every modern organization, verifying their integrity is needed. Watermarking can be used to protect the integrity of database. In this paper, we present a secure fragile embedding watermark technique to verify the authenticity of an outsourced numeric relational database. Our technique treats the watermark embedding as an optimization problem by securely inserting a single watermark bit in individual database partition and the optimal threshold is computed for watermark detection. The approach partitions the database in different groups of square matrix and modifies the database while preserving the field values usability constraints. The database group determinant value is used to compute the position of field to be marked. Furthermore, we evaluated our scheme on a real case study and results show its effectiveness. The proposed scheme can detect and localize the malicious modifications made to the database. The proposed technique is highly resilient to common attacks and it overcomes some limitations of previous approaches on fragile watermarking.

A Novel Olfactory Displays' Scent Dispersing Module

Saad Hameed Abid,Zhiyong Li,Renfa Li,Jumana Waleed 보안공학연구지원센터 2015 International Journal of Hybrid Information Techno Vol.8 No.1

Olfactory display devices have become a recent demand and trend in human computer interaction, providing a new member in the human computer interaction peripheral devices family. These devices enrich the olfactory sense for the user stimulating him/her by means of scent stimuli in correspondence to an object or an event shown on the visual display. Some researches have been done to cover the design, usage and delivery for the scent to the users, other works covered some analysis on the scent categorization and grouping. In this paper a focus is on the controlled atomization of a liquid based scent material while guaranteeing: speed, intensity, durability, compactness and scalability, these important factors are crucial to build a commercial grade olfactory displays containing a universal, interchangeable and versatile but yet durable scent disparity component to facilitate the realization of olfactory display devices.

A Hybrid Cooperative Model for Bandwidth Utilization in Vehicular Ad hoc Networks Based on Game Theory

Esraa Eldesouky,Walaa Elashmawi,Li Renfa,Wang Dong 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.12

Generally speaking, Vehicular Ad hoc Networks comprise vehicles and roadside stations as the common types of nodes. These nodes are mainly providing each other with relevant information. A wide range of applications are supported by Vehicular Ad hoc Networks such as file downloading, or access to the Internet with lack of resource controlling. These challenging resource managements degrade the network performance and create competitive environments. Through this paper, we introduce a novel algorithm for bandwidth sharing enhancement in both vehicle-to-vehicle and vehicle-to-roadside communications. We aim to improve the bandwidth usage based on coalition formation game in order to reduce the cost paid by vehicles for bandwidth reservation at roadsides. Mainly, we intend the enhancement of both individual vehicles’ payoff along with the whole network gain. Simulation results have proven that the proposed algorithm succeed to analyze this conflicting situation efficiently. In addition, satisfaction rates up to 75% have been achieved with an incredibly increase in the network throughput.

Various Roadside Populations Effects on Data Throughput over Cooperative Vehicular Ad hoc Networks

Esraa Eldesouky,Ahmed Ali,Li Renfa,Wang Dong 보안공학연구지원센터 2014 International Journal of Hybrid Information Techno Vol.7 No.6

Roadside units in Vehicular Ad hoc Networks are essential for acting as base stations that facilitate information spreading to vehicular users in the roads. Typically, vehicular nodes search for an infrastructure within their vicinity to fulfill the requested services such as internet accessing or content file handling. Due to the essentiality of the presence of roadsides as well as the high costs for installing them, determining the appropriate roadside populations is an ongoing challenge. According to the surrounding vehicular density, we aim to assure higher data throughput in order to accomplish a cooperative network. This paper considers the roadside populations as to supply vehicles’ requirements based on both a proposed algorithm and simulation results. Moreover, we study the roadside self-participation to enhance the transfer rates and achieve fair resource distribution among the requested vehicles based on coalition formation. Simulation results have proven that the variation of the roadside populations influences the data throughput. Additionally, the cooperative environment among vehicular nodes achieves higher roadside participation ratios especially in the maximum case.

Particle Swarm Optimization and Dempster Shafer Approach to Achieve Internet of Things Context Fusion Using Quality of Context

Ntalasha Derrick,Li Renfa,Wang Yongheng 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.2

Context fusion is a very important aspect in a system that has to adequately simplify a required task in achieving context awareness in the Internet of things (IoT). IoT generates a large amount of data, which are massive, multi-source, heterogeneous, dynamic and sparse. Context information fusion is an important tool in the manipulation and management of these data in order to improve processing efficiency, provide advanced intelligence and increase reliability. Context information fusion can reduce the amount of data traffic, filter noisy measurements, and make predictions and inferences in any stages of data processing in IoT. As such when context is acquired from this domain, it has low confidence level due to reliability factors. In this paper Context information’s reliability has been addressed through the use quality of context (QoC) by determining the combined confidence for acquired context from multiple sources. Particle Swarm Optimization selects the context information with the highest level of confidence and Dempster Shafer rule of combination fuses this context into more reliable information that can be used by the system to effectively adapt to changing context. From the obtained results the proposed solution indicates an improved fusion process with increased confidence.

A Novel Iterative Clipping and Filtering Technique for PAPR Reduction of OFDM Signals: System Using DCT/IDCT Transform

Sroy Abouty,Li Renfa,Zeng Fanzi,Fall Mangone 보안공학연구지원센터 2013 International Journal of Future Generation Communi Vol.6 No.1

A Novel ZCS-Clipping Precoding Technique for PAPR Reduction using DCT-OFDM in Vehicular Channels

Ahmed Ali,Wang Dong,Li Renfa 보안공학연구지원센터 2015 International Journal of Hybrid Information Techno Vol.8 No.5

IEEE 802.11p defines an international standard for wireless access in vehicular environments. It is normally designed for operating at high user mobility. Thus, decreasing the signal bandwidth to 10 MHz in IEEE 802.11p makes the communication more efficient for the vehicular channel. Furthermore, the Orthogonal Frequency Division Multiplexing (OFDM) methodology is commonly used to mitigate the Inter-Symbol Interference (ISI) occurred over a wireless channel. However, the OFDM suffers from certain drawbacks including higher system complexity due to the generation of the peak to average ratio (PAPR). The objective of this study is to reduce the high PAPR resulted from adapting the OFDM system to vehicular networks. In this paper, we propose a novel precoding Zadoff-Chu Sequence (ZCS) combined with the Clipping technique for PAPR reduction in OFDM based on the Discrete Cosine Transform (DCT). The proposed technique which is based on precoding the constellation symbols of the vehicular channels with DCT succeeds to decrease the PAPR ratio up to 4dB for 64 subcarriers.

ISI and PAPR Immune IEEE 802.11p Channels Based on Single-Carrier Frequency Domain Equalizer

( Ahmed Ali ),( Wang Dong ),( Li Renfa ),( Esraa Eldesouky ) 한국인터넷정보학회 2016 KSII Transactions on Internet and Information Syst Vol.10 No.11

Doppler Effect is a prominent obstacle in vehicular networks, which dramatically increase the Bit-Error-Rate (BER). This problem is accompanied with the presence of the Orthogonal Frequency Division Multiplexing (OFDM) systems in which the Doppler shift interrupts the subcarriers orthogonality. Additionally, Inter-Symbol Interference (ISI) and high Peak-to-Average Power Ratio (PAPR) are likely to occur which corrupt the received signal. In this paper, the single-carrier combined with the frequency domain equalizer (SC-FDE) is utilized as an alternative to the OFDM over the IEEE 802.11p uplink vehicular channels. The Minimum Mean Squared Error (MMSE) and Zero-Forcing (ZF) are employed in order to study the impact of these equalization techniques along with the SC-FDE on the propagation medium. In addition, we aim to enhance the BER, improve the transmitted signal quality and achieve ISI and PAPR mitigation. The proposed schemes are investigated and we found that the MMSE outperforms the ZF equalization under different Doppler shift effects and modulations.

Heat based Odors Delivery Apparatus for Interactive Game Playing

Saad Hameed Abid,Zhiyong Li,Renfa Li,Jumana Waleed 보안공학연구지원센터 2015 International Journal of Multimedia and Ubiquitous Vol.10 No.5

Scent delivery systems or what are known as olfactory displays has been the most recent trend in human computer interaction, control and automation, virtual reality, augmented reality, e-commerce and many other fields in the computer world. These devices have the ability to generate smell combinations for some digital items in the computer virtual world. The idea is to deliver additional perception (olfactory perception) to the user to enrich his/her indulgence while interacting with the computer. The proposed olfactory display is similar to this concept but greatly differ in many aspects, using laser based atomization method to produce enough sudden heat to generate odors that cannot be generated using chemical materials these odors are smoke, gun powder, wood milling, cigarettes smoking, plastic melting and Incense. All olfactory displays researchers avoid involving these types of odors in their studies due to the difficulty of the generation and control of such odors and the absence of their correct and precise generation using chemical materials. The proposed system will provide a way of generating such odors while interactive game is being played by a user with minimum impact on the environment to avoid adaption to the user's olfactory system and polluting the environment that the user occupies.

New Stability Conditions for Uncertain T-S Fuzzy Systems with Interval Time-Varying Delay

Jiyao An,Guilin Wen,Tao Li,Renfa Li 제어·로봇·시스템학회 2012 International Journal of Control, Automation, and Vol.10 No.3

This paper focuses on the stability problem for uncertain T-S fuzzy systems with interval time-varying delay. The system uncertainties are assumed to be time-varying and norm-bounded. The time-varying delay is considered as either being differentiable uniformly bounded with delay-derivative bounded by constant interval, or being fast-varying case with no restrictions on the delay derivative. Since we employ a novel Lyapunov-Krasovskii functional (LKF) which contains the information on the time-varying delay, and estimate the upper bound of its derivative less conservatively and adopt the convex optimization approach, some less conservative delay-derivative-dependent stability conditions are obtained in terms of linear matrix inequalities (LMIs), without using any free weighting matrix. These conditions are derived that depends on both the upper and lower bounds of the delay derivatives. Finally, some numerical examples are given to demonstrate the effectiveness and reduced conservatism of the proposed method.