Mohd Yamani Idna Idris

Influence of radiation on double conjugate diffusion in a porous cavity

The current work highlights the effect of radiation on the conjugate heat and mass transfer in a square porous cavity having a solid wall. The solid wall is placed at the center of cavity. The left surface of cavity is maintained at higher temperature Tw and concentration Cw whereas the right surface is maintained at Tc and Cc such that Tw>Tc and Cw>Cc. The top and bottom surfaces are adiabatic. The governing equations are solved with the help of finite element method by making use of triangular elements. The results are discussed with respect to two different heights of solid wall inside the porous medium along with the radiation parameter.

A VHDL implementation of BIST technique in UART design

To increase reliability, manufacturers must be able to discover a high percentage of defective chips during their testing procedures. This paper would highlight the attention given by most customers who are expecting the designer to include testability features that will increase their product reliability. This paper focuses on the design of a UART chip with embedded built-in-self-test (BIST) architecture using FPGA technology. The paper starts by describing the behavior of UART circuit using VHISC hardware description language (VHDL). In the implementation phase, the BIST technique will be incorporated into the UART design before the overall design is synthesized by means of reconfiguring the existing design to match testability requirements.

Simplified finite element algorithm to solve conjugate heat and mass transfer in porous medium

Purpose The purpose of this paper is to highlight the advantages of a simplified algorithm to solve the problem of heat and mass transfer in porous medium by reducing the number of partial differential equations from four to three. Design/methodology/approach The approach of the present paper is to develop a simplified algorithm to reduce the number of equations involved in conjugate heat transfer in porous medium. Findings Developed algorithm/method has many advantages over conventional method of solution for conjugate heat transfer in porous medium. Research limitations/implications The current work is applicable to conjugate heat transfer problem. Practical implications The developed algorithm is useful in reducing the number of equations to be solved, thus reducing the computational resources required. Originality/value Development of simplified algorithm and comparison with conventional method.

Low communication cost (LCC) scheme for localizing mobile wireless sensor networks

Abstract In recent years, the number of applications utilizing mobile wireless sensor networks (WSNs) has increased, with the intent of localization for the purposes of monitoring and obtaining data from hazardous areas. Location of the event is very critical in WSN, as sensing data is almost meaningless without the location information. In this paper, two Monte Carlo based localization schemes termed MCL and MSL* are studied. MCL obtains its location through anchor nodes whereas MSL* uses both anchor nodes and normal nodes. The use of normal nodes would increase accuracy and reduce dependency on anchor nodes, but increases communication costs. For this reason, we introduce a new approach called low communication cost schemes to reduce communication cost. Unlike MSL* which chooses all normal nodes found in the neighbor, the proposed scheme uses set theory to only select intersected nodes. To evaluate our method, we simulate in our proposed scheme the use of the same MSL* settings and simulators. From the simulation, we find out that our proposed scheme is able to reduce communication cost—the number of messages sent—by a minimum of 0.02 and a maximum of 0.30 with an average of 0.18, for varying node densities from 6 to 20, while nonetheless able to retain similar MSL* accuracy rates.

Modeling and simulation of finite state machine Memory Built-in Self Test architecture for embedded memories

Memory built-in self test (MBIST) or as to it array built-in self test is an amazing piece of logic. Without any direct connection to the outside world, a very complex embedded memory can be tested efficiently, easily and less costly. Modeling and simulation of finite state machine (FSM) MBIST is presented in this paper. The design architecture is written in very high speed integrated circuit hardware description language (VHDL) code using Xilinx ISE tools. The architecture is modeled and synthesized using register transfer level (RTL) abstraction. Verification of this architecture is carried out by testing stuck at fault SRAM. A BIST algorithms is implemented i.e March C- to test the faulty SRAM.

A comparison study on node clustering techniques used in target tracking WSNs for efficient data aggregation

Wireless sensor applications are susceptible to energy constraints. Most of the energy is consumed in communication between wireless nodes. Clustering and data aggregation are the two widely used strategies for reducing energy usage and increasing the lifetime of wireless sensor networks. In target tracking applications, large amount of redundant data is produced regularly. Hence, deployment of effective data aggregation schemes is vital to eliminate data redundancy. This work aims to conduct a comparative study of various research approaches that employ clustering techniques for efficiently aggregating data in target tracking applications as selection of an appropriate clustering algorithm may reflect positive results in the data aggregation process. In this paper, we have highlighted the gains of the existing schemes for node clustering-based data aggregation along with a detailed discussion on their advantages and issues that may degrade the performance. Also, the boundary issues in each type of clustering technique have been analyzed. Simulation results reveal that the efficacy and validity of these clustering-based data aggregation algorithms are limited to specific sensing situations only, while failing to exhibit adaptive behavior in various other environmental conditions. Copyright

WDARS: A Weighted Data Aggregation Routing Strategy with Minimum Link Cost in Event-Driven WSNs

Realizing the full potential of wireless sensor networks (WSNs) highlights many design issues, particularly the trade-offs concerning multiple conflicting improvements such as maximizing the route overlapping for efficient data aggregation and minimizing the total link cost. While the issues of data aggregation routing protocols and link cost function in a WSNs have been comprehensively considered in the literature, a trade-off improvement between these two has not yet been addressed. In this paper, a comprehensive weight for trade-off between different objectives has been employed, the so-called weighted data aggregation routing strategy (WDARS) which aims to maximize the overlap routes for efficient data aggregation and link cost issues in cluster-based WSNs simultaneously. The proposed methodology is evaluated for energy consumption, network lifetime, throughput, and packet delivery ratio and compared with the InFRA and DRINA. These protocols are cluster-based routing protocols which only aim to maximize the overlap routes for efficient data aggregation. Analysis and simulation results revealed that the WDARS delivered a longer network lifetime with more proficient and reliable performance over other methods.

Passive video forgery detection techniques: A survey

Technological advancement of various video and image processing tools has made tempering of digital video easy and faster. This review paper focuses on passive techniques that are employed for detecting forgeries in a digital video. Passive forgery detection techniques are methods used for detecting the authenticity of a video without depending on pre-embedded information. The techniques exploit the use of statistical or mathematical properties that are distorted as a result of video tempering for forgery detection. Passive video forgery detection approach has a great prospect in multimedia security, information security and pattern recognition. In this paper, we divide passive techniques for video forensics into three categories; Statistical correlation of video features, frame-based for detecting statistical anomalies, and the inconsistency features of different digital equipment. The discussion also covers the trends, limitations and idea for improvements of passive forgery detection techniques.

Blind source mobile device identification based on recorded call

Mel-frequency cepstrum coefficients (MFCCs) extracted from speech recordings has been proven to be the most effective feature set to capture the frequency spectra produced by a recording device. This paper claims that audio evidence such as a recorded call contains intrinsic artifacts at both transmitting and receiving ends. These artifacts allow recognition of the source mobile device on the other end through recording the call. However, MFCC features are contextualized by the speech contents, speakers characteristics and environments. Thus, a device-based technique needs to consider the identification of source transmission devices and improve the robustness of MFCCs. This paper aims to investigate the use of entropy of Mel-cepstrum coefficients to extract intrinsic mobile device features from near-silent segments, where it remains robust to the characteristics of different speakers. The proposed features are compared with five different combinations of statistical moments of MFCCs, including the mean, standard deviation, variance, skewness, and kurtosis of MFCCs. All feature sets are analyzed by using five supervised learning techniques, namely, support vector machine, naive Bayesian, neural network, linear logistic regression, and rotation forest classifier, as well as two unsupervised learning techniques known as probabilistic-based and nearest-neighbor-based algorithms. The experimental results show that the best performance was achieved with entropy-MFCC features that use the naive Bayesian classifier, which resulted in an average accuracy of 99.99% among 21 mobile devices. The method used the combination of entropy and MFCCs from near-silent frames.Entropy-MFCC features exhibit high performance against statistical moments of MFCCs.The traces of the source transmitting devices were identified from recorded call.The method can be implemented through other service providers, i.e. cellular, PSTN.

SIFT-Symmetry: A robust detection method for copy-move forgery with reflection attack

Abstract Copy-move forgery (CMF) is a popular image manipulation technique that is simple and effective in creating forged illustrations. The bulk of CMF detection methods concentrate on common geometrical transformation attacks (e.g., rotation and scale) and post-processing attacks (e.g., Joint Photographic Experts Group (JPEG) compression and Gaussian noise addition). However, geometrical transformation that involves reflection attacks has not yet been highlighted in the literature. As the threats of reflection attack are inevitable, there is an urgent need to study CMF detection methods that are robust against this type of attack. In this study, we investigated common geometrical transformation attacks and reflection-based attacks. Also, we suggested a robust CMF detection method, called SIFT-Symmetry, that innovatively combines the Scale Invariant Feature Transform (SIFT)-based CMF detection method with symmetry-based matching. We evaluated the SIFT-Symmetry with three established methods that are based on SIFT, multi-scale analysis, and patch matching using two new datasets that cover simple transformation and reflection-based attacks. The results show that the F-score of the SIFT-Symmetry method surpassed the average 80% value for all geometrical transformation cases, including simple transformation and reflection-based attacks, except for the reflection with rotation case which had an average F-score of 65.3%. The results therefore show that the SIFT-Symmetry method gives better performance compared to the other existing methods.