AIUB Journal of Science and Engineering (AJSE) <p><span style="display: inline !important; float: none; background-color: transparent; color: #333333; font-family: Roboto,sans-serif; font-size: 15.73px; font-size-adjust: none; font-stretch: 100%; font-style: normal; font-variant: normal; font-weight: 300; letter-spacing: normal; line-height: 28.31px; orphans: 2; text-align: left; text-decoration: none; text-indent: 0px; text-shadow: none; text-transform: none; -webkit-text-stroke-width: 0px; white-space: normal; word-spacing: 0px;">The core vision of this journal is to propagate innovative information and technology to promote the academic and research professionals in the field of Science, Technology, and Engineering. The aim of AJSE is to create a broad platform for academicians, researchers, and industries to present and publish their innovative researches and to disseminate the articles for research, teaching, and reference purposes.</span></p> <p><strong><span style="float: none; background-color: transparent; color: #333333; font-family: Roboto, sans-serif; font-size: 15.73px; font-stretch: 100%; font-style: normal; font-variant: normal; letter-spacing: normal; line-height: 28.31px; orphans: 2; text-align: left; text-decoration: none; text-indent: 0px; text-shadow: none; text-transform: none; -webkit-text-stroke-width: 0px; white-space: normal; word-spacing: 0px; display: inline !important;">AJSE has been accepted for <a href="">SCOPUS indexing</a> from 2018 and onwards issues.</span></strong></p> en-US <p><span style="display: inline !important; float: none; background-color: #ffffff; color: #333333; font-family: 'Ubuntu',Tahoma,'Helvetica Neue',Helvetica,Arial,sans-serif; font-size: 14px; font-style: normal; font-variant: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: left; text-decoration: none; text-indent: 0px; text-transform: none; -webkit-text-stroke-width: 0px; white-space: normal; word-spacing: 0px;">All contents of the AIUB JOURNAL OF SCIENCE AND ENGINEERING Web Site are: Copyright 2019 by AJSE and/or its suppliers. All rights reserved.</span></p> (Dr. Carmen Z. Lamagna) (Dr. M Tanseer Ali) Sat, 15 May 2021 18:00:28 +0000 OJS 60 Design and Evaluation of a 32-bit Carry Select Adder using 4-bit Hybrid CLA Adder <p>Adder circuits play a remarkable role in modern microprocessor. Adders are widely used in critical paths of arithmetic operation such as multiplication and subtraction. A Carry Select Adder (CSA) design methodology using a modified 4-bit Carry Look-Ahead (CLA) Adder has been proposed in this research. The proposed 4-bit CLA used hybrid logic style based logic circuits for Carry Generate (Gi) and Carry Propagate (Pi) functions in order to improve performance and reduce the number of transistor used. The modified 4-bit CLA is used as the basic unit for implementation of 32-bit CSA. The proposed design of hybrid CLA based 32-bit CSA has been compared with conventional static CMOS based 32-bit CSA and 32-bit Ripple Cary Adder (RCA) by conducting simulation using Cadence Virtuoso. Power consumption and delay in the proposed 32-bit CSA found 322.6 (uW) and 0.556 (ns) whereas power and delay in the conventional 32-bit CSA was 455.4 (uW) and 0.667 (ns) respectively. We have done all the simulation using Cadence Virtuoso 90 nm tool.</p> Muhammad Saddam Hossain, Farhadur Arifin Copyright (c) 2021 AIUB Journal of Science and Engineering (AJSE) Sat, 15 May 2021 00:00:00 +0000 Investigation of Security Challenges from the Perspective of Stakeholders in IoT <p><strong><em>Internet of Things (</em></strong><strong>IoT) has become one of the major study concerns and prospects in recent times. The ecosystem that makes the interconnection between person, objects, device in a secured acceptable and useful manner is in the boundary of Internet of Things. One of the major concerns in IoT is its security and the technologies which are working behind. The security measures are taken under a vast amount of studies and applications. The concept of this research is to consider the existing technologies that are working for security assurance and the challenges which are faced by different angles of participants and manufacturers due to make IoT a secure electronic ecosystem. Basically, the focus over the security challenges are on the stakeholders and they are user, manufacturer and service provider.</strong></p> Md Sajid Bin Faisal, Ahsan Habib, Md Aolad Hossain , Cynthia Simin Rashid, Dip Nandi Copyright (c) 2021 AIUB Journal of Science and Engineering (AJSE) Sat, 15 May 2021 00:00:00 +0000 Design and Performance Analysis of a PV Control Scheme to Improve LVRT of Hybrid Power System. <p>Solar power stations worldwide have been rising every year as well as the usage of sustainable power has increased. The addition into the traditional electricity grid networks of renewable sources such as the photovoltaic (PV) system is an essential challenge, given its erratic power generation. The major issue is to detach PV from the faulty grid, which leads to fluctuation in the system's interconnected PV system and system-wide energy interruptions. The low voltage ride through (LVRT) enables the PV scheme should stay linked to the grid even under fault situations in short periods and must assist the grid return to regular situations according to the modern grid codes. Hence, this paper develops and analyzes five aspects of control strategy to increase PV station's LVRT capability. The in-depth simulation of the independent units of the grid-connected large-scale PV farm is accomplished using PSCAD/EMTDC to assess the feasibility of the suggested control tactic for the modified IEEE nine-bus system.</p> S. M. Istiaque Mahmud, Mohammad Abdul Mannan, Md. Rifat Hazari Copyright (c) 2021 AIUB Journal of Science and Engineering (AJSE) Sat, 15 May 2021 00:00:00 +0000 Design of a Robust ESD Protection Device using 6H-SiC Nano-Scale GGNMOS <p>With the continuous shrinking of the technological nodes and the introduction of new device concepts and materials, integrated circuits (IC) are becoming more vulnerable to electrostatic discharge (ESD) induced failures which is one of the major concerns in designing robust ICs. &nbsp;Therefore, to improve the reliability of the ICs against ESD induced failures, extensive research efforts are being conducted. In this paper, we have presented a 6H-SiC based nano-scale grounded-gate NMOS (ggNMOS) ESD protection device and compared the results with the 3C-SiC-based ggNMOS. To design a robust ESD protection device, some critical device parameters, such as substrate doping concentration, source/drain doping concentration, drain to substrate contact spacing, and substrate contact resistance should be optimized. The ESD protection characteristics can be improved by utilizing the near punch-through effect. It was found that the trigger voltage and hold voltage are higher in 6H-SiC than the 3C-SiC having identical device parameters. 6H-SiC shows better voltage clamping performance as the turn-on resistance of 6H-SiC is smaller compared to the 3C-SiC material. Therefore, the results show that 6H-SiC has a better performance compared to 3C-SiC and due to its higher bandgap, and can be used as a good ESD protection device. All the simulations are carried out using the Silvaco ATLAS device simulator.</p> Shirazush Salekin Chowdhury, Farhadur Arifin Copyright (c) 2021 AIUB Journal of Science and Engineering (AJSE) Sat, 15 May 2021 09:34:37 +0000 Design and Development of Citizen Surveillance and Social-Credit Information System for Bangladesh <p>Most of the areas of Bangladesh face a wide range of threats, ranging from terrorism and civil unrest to kidnapping, rape and murder. To reduce the impact of these threats, it is critical for the authorities to capture real-time information on<strong><br></strong>what is happening in and around the city. Therefore, there is a growing requirement for utilizing the new and emerging technologies to make our cities safer. The development of the monitoring system in the technological field has become a blazing topic in the milieu of scholars and AI techniques have become an essential part of the future era. With the help of AI &amp; deep learning, we can evaluate the social behavior (Action Recognition) of people, and by implementing the social credit score system, we can mark the citizen’s activities &amp; analyze them. To detect and recognize the actions of a human we used YOLOV2 architecture and also incorporated the SQL database (SQLite) to record the social credit score. A citizen can visualize their credit score from an HTML based website.</p> Anjir Ahmed Chowdhury Shuvo, Sabrina Kashem Chowdhury, Md Hanif, Sadia Noor Nosheen, Md. Saniat Rahman Zishan Copyright (c) 2021 AIUB Journal of Science and Engineering (AJSE) Sat, 15 May 2021 09:35:41 +0000 Design and Comparison of grid connected Permanent Magnet Synchronous Generator Non-salient Pole and Salient Pole Rotor Wind Turbine <p>Variable speed wind turbines are widely used wind energy conversion system (WECS). Among them doubly fed induction generator (DFIG) and permanent magnet synchronous generator (PMSG) are mostly used. PMSG based wind turbines are getting more popular in recent times because of their several advantages over other types. Direct drive capability and low speed operation are some of it’s significant advantage over other type. This paper describes two rotor types of grid connected PMSG, non-salient pole or round pole rotor and salient pole rotor and shows a comparative study between them. The mathematical model was designed and simulated using Matlab/Simulink. Simulation results have been shown to analyze their performances.</p> S.M. Mehedi Hasan, Abu Hena Md. Shatil Copyright (c) 2021 AIUB Journal of Science and Engineering (AJSE) Sat, 15 May 2021 09:37:11 +0000 Identification of Risk of Occurring Skin Cancer (Melanoma) Using Convolutional Neural Network (CNN) <p class="Abstract">Skin cancer is one of the most common malignancy in human, has drawn attention from researchers around the world. As skin cancer can turn into fatal if not treated in its earliest stages, the necessity of devising automated skin cancer diagnosis system that can automatically detect skin cancer efficiently in its earliest stage in a faster process than traditional one is of crucial importance. In this paper, a computer aided skin cancer diagnosis system based Convolutional Neural Network method has been shown. Our proposed system consists of five stages namely image acquisition, image preprocessing, image segmentation, feature extraction and classification We remove hair any noise from the images using dull then use median filter to smoothen the images. Next, k-means algorithm was applied for image segmentation on the preprocessed images. Finally, the segmented images were fed into CNN model for feature extraction and classification. The developed system can classify benign and melanoma type skin cancers from Dermoscopic images as accurate as 80.47%. While developing the skin cancer detection system, we compare accuracy score of other models such as Artificial Neural Network (ANN), K-Nearest Neighbor (KNN) and Random Forest with our proposed system. The proposed method has been tested on ‘ISIC Challenge 2016’ test dataset and an accuracy rate of 80.47% was obtained for accurately classifying benign and malignant skin lesions by our proposed model.</p> Mayinuzzaman Shawon, Kazi Fakhrul Abedin, Anik Majumder, Abir Mahmud, Md Mahbub Chowdhury Mishu Copyright (c) 2021 AIUB Journal of Science and Engineering (AJSE) Sat, 15 May 2021 09:37:59 +0000