Chittagong University of Engineering & Technology

About: Chittagong University of Engineering & Technology is a education organization based out in Chittagong, Bangladesh. It is known for research contribution in the topics: Computer science & Renewable energy. The organization has 1200 authors who have published 1444 publications receiving 10418 citations. The organization is also known as: Engineering College, Chittagong & Bangladesh Institute of Technology, Chittagong.

Robust Audio Watermarking Scheme Based on Deterministic Plus Stochastic Model

Abstract: Digital watermarking has been widely used for protecting digital contents from unauthorized duplication. This paper proposes a new watermarking scheme based on spectral modeling synthesis (SMS) for copyright protection of digital contents. SMS defines a sound as a combination of deterministic events plus a stochastic component that makes it possible for a synthesized sound to attain all of the perceptual characteristics of the original sound. In our proposed scheme, watermarks are embedded into the highest prominent peak of the magnitude spectrum of each non-overlapping frame in peak trajectories. Simulation results indicate that the proposed watermarking scheme is highly robust against various kinds of attacks such as noise addition, cropping, re-sampling, re-quantization, and MP3 compression and achieves similarity values ranging from 17 to 22. In addition, our proposed scheme achieves signal-to-noise ratio (SNR) values ranging from 29 dB to 30 dB.

Prospect of Back Contact for A Highly Efficient InGaN Thin Film Solar Cell from Numerical Analysis

Abstract: Nowadays, solar photovoltaic (PV) is the most attractive and sustainable technology to solve the present power crisis. Indium Gallium Nitride (InGaN) is an amazing photovoltaic material that has tunable bandgap ranging from 0.7 eV - 3.4 eV that can cover the total solar spectrum to increase the efficiency abundantly. Recently, InGaN alloy is exhibiting its potential for various optoelectronic and power electronic applications. Such excellent semiconductor alloy from group III-V is motivating enormous research interest to build highly efficient photovoltaic cell. This paper works on the prospect of back contact materials by the performance of InGaN solar cells. The rigorous simulation was conducted with several ratios of In in InGaN with different thickness of P and N layer of the single junction solar cell. Different cell structures were examined through AMPS-1D simulator to discover the stable and efficient InGaN cell. Nine different cell structures were investigated to find the stable and efficient InGaN cell where Ti, Mo, Cu, Ni, Pt, Au, Co, Al, Ag, etc. were used as back contact materials and found a high conversion efficiency of 25.06%. Stability of the cell structure was also investigated that is -0.04/◦C shows the high stability.

A Framework for Traffic Sign Detection Based on Fuzzy Image Processing and Hu Features

Abstract: The Traffic Sign Recognition (TSR) system is an essential part of traffic management, being support system for driver and intelligent vehicle. Traffic Sign Detection (TSD) is the prerequisite step of the automatic TSR system. This paper proposes a TSD framework by exploring fuzzy image processing and invariant geometric moments. In this framework, fuzzy inference system is applied to convert the HSV image into gray tone. Then, statistical threshold is used for the segmentation. After shape verification of every connected component using Hu moments and Quadratic Discriminant Analysis (QDA) model, the candidate signs are detected by referencing bounding box parameters. The framework is simulated in different complex scenarios of day and night mode. Experimental result shows that its performance is satisfactory and recommendable with the state of the art research. The proposed framework yields 94.86% F-measure in case of Bangladesh road signs and 93.01% in German road signs.

A Novel Block Cipher Based on Randomly Shuffled Key Strings

Abstract: Information security has immense importance in today’s world of digital communication. Sharing information between intended parties while keeping it secret from any outsider is a challenging task. Cryptography provides the security of information by keeping the information secret among only the communicating parties. In this paper, a new cryptographic algorithm is propounded, which is a block cipher algorithm. A positive integer, n, two $$n\times 256$$ tables of ASCII characters, and a string, Mapper, are used as shared private keys in the proposed method. Every row of the key tables and Mapper contains a random permutation of all the ASCII characters. In the beginning of encryption of a block, an Exclusive Or (XOR) operation is done between the block and a random array of integers. Then, a 3-round substitution operation is done using the key tables and Mapper. We found that the encryption and the decryption speed of the proposed algorithm is faster than the encryption–decryption speed of Advanced Encryption Standard (AES) and Data Encryption Standard (DES). The strength of the proposed cipher was analyzed in the light of some popular attacks, and we found that the system is strong enough against those attacks. We hope that if integrated with the modern cryptography protocols, this method will enhance modern digital communication security.