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.

Dielectric and optical properties of Ni-doped LaFeO3 nanoparticles

Abstract: Un-doped and Ni-doped lanthanum ferrite nanoparticles were synthesized by solid-state method. Ni concentration-dependent structural, dielectric and optical properties of synthesized nanoparticles were investigated. X-ray diffraction patterns confirmed predominant single-phase orthorhombic crystal structure with space group Pbnm in all samples. Average crystallite size was found to vary from 19 to 21 nm with Ni concentration. The field emission scanning electron microscopy revealed nanocrystalline structure with homogenous distribution of particles. UV–Vis–NIR diffuse spectra captured at room temperature indicate that La1−xNixFeO3 is an indirect band gap material. The band gap varies from 1.70 to 1.85 eV with changing Ni concentration. Frequency-dependent dielectric constant, dielectric loss and ac conductivity were studied at room temperature. The dielectric constant was found to increase with increasing Ni content at high frequency. The loss factor resulted from domain wall resonance exhibited an identical dispersion behavior of dielectric constant. At high frequencies, the dielectric losses of orthoferrites were found to be low. This is attributed to the restricted motion of domain wall pointing its plausible practical applications in magnetically tunable filters and oscillators.

Artificial neural network based soft-starter for induction motor

Abstract: The necessity of soft-starter is increasing day by day to reduce the starting current & to maintain the torque smoothly according to the load requirement. Now intelligent soft-starter is developed to improve the performance of conventional starter. This paper focused on the designing of an artificial neural network controlled soft-starter. Back-propagation algorithm is used as learning algorithm in the artificial neural network. Error correcting capability of this learning algorithm makes it more suitable to use in neural network. For comparative performance analysis two different types of back propagation algorithms are used in the neural network learning process. According to condition of learning rate parameter gradient descent with momentum back-propagation algorithm provide better response. A comparative study between conventional starting method (Direct on Line)and proposed soft-starter. Artificial Neural Network controlled soft-starter is able to reduce starting current compared with DOL method & able to accelerate the load at starting period efficiently compared with star-delta starting method.

A machine translation framework for translating Bangla assertive, interrogative and imperative sentences into English

Abstract: This paper proposes a technique to translate Bangla sentence into corresponding English sentence using context sensitive grammar rules. A set of context sensitive grammar rules is proposed to translate Bangla sentences including assertive, interrogative and imperative sentences. The proposed rules are developed based on the mood or intonation of sentences rather than structure of the sentences. Machine translation system works with three major steps: parsing, transfer and generation. We propose algorithms for these three major stages. The evaluation result reveals that the proposed machine translation system can translate Bangla sentences into English with 83% accuracy and gives better accuracy compare to the Google translator for some selected sentences.

Freighter fuel level detection and overload alarming system with safety notification via GSM

Abstract: A PIC microcontroller based digital electronic system has been designed to monitor the fuel level and total amount of load on the freighter and generate scan report for the captain of the freighter. The system is designed for three different freighter load levels; no load, optimal load and over load. At initial level it remains in no load status, when load increases and still remain in optimal level then the system notify crews to initiate voyage. If the load increases to over load level then the system gives alarm and sends alert message to the main control tower for necessary initiative. The communication between the vessel and main control tower is done by GSM module to ensure long distance reliable communication. For amenity, freighter fuel level is monitored in both analogue and digital scale. The system is implemented by PIC midrange microcontroller based hardware and low cost GSM module which makes it more economic, reliable and efficient.

Understanding the improvement of thermo-mechanical and optical properties of 212 MAX phase borides Zr2AB2 (A = In, Tl)

Abstract: In this paper, a first-principles study of the newly known MAX phase borides Zr2AB2 (A = In, Tl) has been carried out. The stiffness constants, elastic moduli, mechanical anisotropy, thermal and optical properties are investigated for the first time. The structural lattice parameters are found to be consistent with previous study. The dynamical and mechanical stability of the titled compounds have been checked. Fundamental insights into the stiffness constants, elastic moduli, hardness parameters, brittleness and anisotropy indices are presented. The variation of these mechanical properties is explained based on the Mulliken population analysis and charge density mapping (CDM). The metallic nature and anisotropy in conductivity has been confirmed from the electronic band structure. The analysis of DOS revealed the dominant contribution from Zr-d orbitals to the conductivity. The higher values of ΘD and Tm, and lower value of Kmin for Zr2AB2 (A = In, Tl) compared to those of Zr2AC (A = In, Tl) suggest enhanced thermal properties of the compounds under study for practical applications. Besides, the specific heat capacities (Cv, Cp), thermal expansion coefficient, and different thermodynamic potential functions have been calculated. The technologically important optical constants have been studied with an intention to reveal their possible relevance for application purposes. The reflectivity spectra revealed the applicability of Zr2AB2 (A = In, Tl) as cover materials to diminish the solar heating. The studied physical properties of Zr2AB2 (A = In, Tl) are compared with those of other relevant 212 and 211 MAX phase nanolaminates.