AIUB Journal of Science and Engineering (AJSE)最新文献_第7页

Online Education in HEIs in Bangladesh moderated by COVID-19: Modified UTAUT2 受COVID-19影响的孟加拉国高等学校在线教育:修改后的UTAUT2

AIUB Journal of Science and Engineering (AJSE) Pub Date : 2021-12-30 DOI: 10.53799/ajse.v20i4.197

S. Khan, Nurakmal Ahmad Mustaffa, M. Habib

{"title":"Online Education in HEIs in Bangladesh moderated by COVID-19: Modified UTAUT2","authors":"S. Khan, Nurakmal Ahmad Mustaffa, M. Habib","doi":"10.53799/ajse.v20i4.197","DOIUrl":"https://doi.org/10.53799/ajse.v20i4.197","url":null,"abstract":"The whole world, including Bangladesh is brought to a standstill by the pandemic of COVID-19. All the hustling-bustling of a densely populated country has come to a quiescent halt; the only sound remaining is the whisper of anxiety. The HEIs in Bangladesh is also struggled to react to this sudden catastrophe; magnified by uncertainties. Compared to public universities, the private universities of the country managed to react the fastest and are making sweeping changes in a very short period of time, shifting traditional face-to-face course content/teaching to online content/teaching. The shift to fully functional online teaching learning platform was sudden and with minimum preparation. To investigate the perception of the private universities community in Bangladesh with this new teaching learning method, this paper adopted the Unified Theory of Acceptance and Use of Technology (UTAUT) model, focuses on stakeholders’ behavioral intention, availability of the online platform, prior experience, attitude towards usage (ease of use and usefulness) and most importantly the impact of COVID-19 pandemic. Additionally, the paper also discusses the issues of social and cultural impact. It was found that all the UTAUT attributes are positively correlated with the Behavioral Intention and eventually to Use Behavior of students in adopting online education. Moreover, unexpected, and unprecedented impact of COVID-19 pandemic also effected their behavioral intention towards accepting online education.","PeriodicalId":224436,"journal":{"name":"AIUB Journal of Science and Engineering (AJSE)","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127122126","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Energy Harvesting Technology by Converting Waste Heat Energy from Automobiles 利用汽车余热转化的能量收集技术

AIUB Journal of Science and Engineering (AJSE) Pub Date : 2021-12-30 DOI: 10.53799/ajse.v20i4.180

Md. Abdullah Al Rakib, Md. Saniat Rahman Zishan, Md. Abid Hasan Abid

引用次数: 0

FRT and Transient Stability Augmentation of Grid-Connected PV Station Using Virtual Synchronous Generator 利用虚拟同步发电机增强并网光伏电站的FRT和暂态稳定

AIUB Journal of Science and Engineering (AJSE) Pub Date : 2021-12-30 DOI: 10.53799/ajse.v20i4.171

M. Islam, M. Mannan, Md. Rifat Hazari

{"title":"FRT and Transient Stability Augmentation of Grid-Connected PV Station Using Virtual Synchronous Generator","authors":"M. Islam, M. Mannan, Md. Rifat Hazari","doi":"10.53799/ajse.v20i4.171","DOIUrl":"https://doi.org/10.53799/ajse.v20i4.171","url":null,"abstract":"Due to the extensive integration of renewable energy sources (RESs), i.e., photovoltaic (PV) system, the future power system is developing into an inverter-based system from a dominated alternator-based power system. This massive penetration of inverter-based PV system reduced the system inertia and damping characteristics of the power grid, impacting the fault ride-through (FRT) capability and causes frequency instability. Modern grid codes require that PV systems should work in the same way as conventional power plants and assist the system during transient state. However, most of the conventional inverter control mechanisms failed to fulfill the requirements of grid codes, especially when the penetration ratio of the PV system is close to the conventional unit. Therefore, this paper proposes a virtual synchronous generator (VSG) control mechanism of PV system inverter to augment FRT competency and frequency stability. The proposed VSG control system mimics the behavior of conventional power plants. To observe and evaluate the proposed controller behavior, simulation analyses were executed in the PSCAD/EMTDC software for both proposed and conventional controllers. The simulation results clearly indicate that the proposed VSG control system has sufficient damping characteristics to ensure FRT capability and frequency stability. ","PeriodicalId":224436,"journal":{"name":"AIUB Journal of Science and Engineering (AJSE)","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129920421","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Integrated Mobile Learning Education Supply Chain Management for Higher Learning Institution 高校集成移动学习教育供应链管理

AIUB Journal of Science and Engineering (AJSE) Pub Date : 2021-12-30 DOI: 10.53799/ajse.v20i4.289

Mashiour Rahman, R. A. Rahman, M. Habib

引用次数: 1

Study and Analysis of Photonic Crystal Fiber for Broadband Laser Source Design 用于宽带激光光源设计的光子晶体光纤的研究与分析

AIUB Journal of Science and Engineering (AJSE) Pub Date : 2021-12-30 DOI: 10.53799/ajse.v20i4.200

M. Faisal, Sk. M. Jahangir Kabir

引用次数: 0

A PLS-SEM Approach to Connect Fertility, GDP, and Childhood Mortality with Female life Expectancy (FLE) in Bangladesh PLS-SEM方法将生育率、GDP和儿童死亡率与孟加拉国女性预期寿命(FLE)联系起来

AIUB Journal of Science and Engineering (AJSE) Pub Date : 2021-12-30 DOI: 10.53799/ajse.v20i4.210

M. Ahmmed, M. Babu, M. A. Hoque, M. M. Rahman

引用次数: 3

Review of Different Error Metrics: A Case of Solar Forecasting 不同误差度量的回顾:以太阳预报为例

AIUB Journal of Science and Engineering (AJSE) Pub Date : 2021-12-30 DOI: 10.53799/ajse.v20i4.212

Pardeep Singla, M. Duhan, Sumit Saroha

{"title":"Review of Different Error Metrics: A Case of Solar Forecasting","authors":"Pardeep Singla, M. Duhan, Sumit Saroha","doi":"10.53799/ajse.v20i4.212","DOIUrl":"https://doi.org/10.53799/ajse.v20i4.212","url":null,"abstract":"Renewable energy systems (RES) are no longer confined to being used as a stand-alone entity in the modern era. These RES, especially solar panels are also used with the grid power systems to supply electricity. However, precise forecasting of solar irradiance is necessary to ensure that the grid operates in a balanced and planned manner. Various solar forecasting models (SFM) are presented in the literature to produce an accurate solar forecast. Nevertheless, each model has gone through the step of evaluation of its accuracy using some error measures. Many error measures are discussed in the literature for deterministic as well as probabilistic solar forecasting. But, each study has its own selected error measure which sometimes landed on a wrong interpretation of results if not selected appropriately. As a result, this paper offers a critical assessment of several common error metrics with the goal of discussing alternative error metrics and establishing a viable set of error metrics for deterministic and probabilistic solar forecasting. Based on highly cited research from the last three years (2019-2021), error measures for both types of forecasting are presented with their basic functionalities, advantages & limitations which equipped the reader to pick the required compatible metrics","PeriodicalId":224436,"journal":{"name":"AIUB Journal of Science and Engineering (AJSE)","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128290169","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Multi-Modal Case Study on MRI Brain Tumor Detection Using Support Vector Machine, Random Forest, Decision Tree, K-Nearest Neighbor, Temporal Convolution & Transfer Learning 基于支持向量机、随机森林、决策树、k近邻、时间卷积和迁移学习的MRI脑肿瘤检测多模态案例研究

AIUB Journal of Science and Engineering (AJSE) Pub Date : 2021-09-26 DOI: 10.53799/ajse.v20i3.175

P. Sutradhar, Prosenjit Kumer Tarefder, Imran Prodan, Md. Sheikh Saddi, Victor Stany Rozario

{"title":"Multi-Modal Case Study on MRI Brain Tumor Detection Using Support Vector Machine, Random Forest, Decision Tree, K-Nearest Neighbor, Temporal Convolution & Transfer Learning","authors":"P. Sutradhar, Prosenjit Kumer Tarefder, Imran Prodan, Md. Sheikh Saddi, Victor Stany Rozario","doi":"10.53799/ajse.v20i3.175","DOIUrl":"https://doi.org/10.53799/ajse.v20i3.175","url":null,"abstract":"In the Medical field, Brain Tumor Detection has become a critical and demanding task because of its several shapes, locations, and intensity of image. That’s why an automated system is important to aid physicians and radiologists in detecting and classifying brain tumors. In this research, we have discussed different machine learning as well as deep learning algorithm which are mostly used for image classification. We have also compared different models that are being used for tumor classification based on machine learning and deep learning. MRI images of Glioma tumor, Pituitary tumor, Meningioma tumor are the base of this research, and we have compared different techniques along with the accuracy of different classification models using those MRI images. We have used different deep learning pre-trained models for training the brain tumor images. Those pre-trained models have provided outstanding performance along with less power consumption and computational time. EfficientNet-B3 has provided the best accuracy of 98.16% among other models as well as traditional machine learning algorithms. The experimental result of this model is proven the best and most efficient for tumor detection and classification in comparison with other recent studies.","PeriodicalId":224436,"journal":{"name":"AIUB Journal of Science and Engineering (AJSE)","volume":"48 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132863224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Linearization of High frequency Class E Feedback Amplifier using Negative Impedance Method 高频E类反馈放大器的负阻抗线性化

AIUB Journal of Science and Engineering (AJSE) Pub Date : 2021-09-23 DOI: 10.53799/ajse.v20i3.166

Md. Shoaib Sikder, M. Tanseer Ali

{"title":"Linearization of High frequency Class E Feedback Amplifier using Negative Impedance Method","authors":"Md. Shoaib Sikder, M. Tanseer Ali","doi":"10.53799/ajse.v20i3.166","DOIUrl":"https://doi.org/10.53799/ajse.v20i3.166","url":null,"abstract":"This work represents a novel method of linearization of Switch Mode Power Amplifier (SMPA). For this purpose, class E SMPA was designed and analyzed both before and after applying a linearization technique known as Negative Impedance method. One of the major characteristics of a standard SMPA is that they poses high efficiency than their linear counterpart but on the other hand they show highly nonlinear characteristics. The motivation behind this work is to harness this highly efficient amplifier and make it linear which can very useful for various applications in RF communication fields. All the schematics and simulations that are presented in this paper was performed using Cadence Virtuoso environment using “Spectre” simulator tool. For active components, 280nm process technology was used under “gpdk90” pdk which based on BSIM3v3 model. Circuit was designed to run at 2GHz with 2.5 V supply voltage. A mathematical model is also presented using data found from the analysis, with the help of MATLAB. Linearity was measured using Input referred Intercept Point of 3rd order frequency (IIP3), which was improved from 3.7dBm to 17.86dBm with 57% percent efficiency providing an output power of 15.78dBm.","PeriodicalId":224436,"journal":{"name":"AIUB Journal of Science and Engineering (AJSE)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128490819","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Impact of COVID-19 on Academic and Psychological aspects of Undergraduate Students in Bangladesh: A Case Study 2019冠状病毒病对孟加拉国大学生学业和心理方面的影响:个案研究

AIUB Journal of Science and Engineering (AJSE) Pub Date : 2021-09-23 DOI: 10.53799/ajse.v20i3.169

M. Ahmmed, M. M. Rahman, Abhijit Bhowmik, A. Siddiqua

{"title":"Impact of COVID-19 on Academic and Psychological aspects of Undergraduate Students in Bangladesh: A Case Study","authors":"M. Ahmmed, M. M. Rahman, Abhijit Bhowmik, A. Siddiqua","doi":"10.53799/ajse.v20i3.169","DOIUrl":"https://doi.org/10.53799/ajse.v20i3.169","url":null,"abstract":"Undergraduate students are considered susceptible in terms of anxiety, drug abuse, depression, and bad dietary habits in comparison to the general people. Their academic and psychological facets have severely been altered due to COVID-19 pandemic. The objective of this study is to identify the effect of COVID-19 on the academic and psychological aspects of undergraduate students in Bangladesh accompanied by other pertinent factors. Data were accumulated from the undergraduate students of the Fall semester 2020-21 of American International University-Bangladesh (AIUB) by questionnaire provided through Microsoft Forms. The associations among the variables were assessed through the chi-square test. All the statistical analyses required to meet the goals of the study were done through Statistical Package for Social Sciences (SPSS). Nearly one-fourth of the students suffered from anxiety and depression at an extreme level while close to one-third of them suffered quite a bit signaling a tormenting psychological state of the students. Chi-square tests found that depression, anxiety, study hour, assessment of online learning, and income issue due to COVID-19 of the student had a highly significant association with effects on their study and psychological aspects. Failure to address the aforesaid issues during an epidemic might have negative consequences on the academic and psychological aspects in the long run.","PeriodicalId":224436,"journal":{"name":"AIUB Journal of Science and Engineering (AJSE)","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116692031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3