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Groundwater arsenic poisoning in a primary educational institution:health risks to school-going children

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Acta Geochimica 2022年第6期41卷 1069-1082页

作者： md.Sohel Rana md.Jahangir Alam mdAbu Musa Sazal Kumar md.Aminur rahman Zonal Laboratory Department of Public Health Engineering(DPHE)RangpurBangladesh Department of Chemistry Carmichael CollegeRangpurBangladesh Department of Applied Chemistry and Chemical Engineering Islamic UniversityKushtia7003Bangladesh School of Environmental and Life Sciences The University of NewcastleCallaghanNSW2308Australia Global Centre for Environmental Remediation(GCER) College of EngineeringScience and EnvironmentThe University of NewcastleCallaghanNSW2308Australia Zonal Laboratory Department of Public Health Engineering(DPHE)Jashore-7400Bangladesh

This study aimed to estimate arsenic(As)and iron(Fe)content in tubewell water(n=58)in primary educational institutions and subsequently assess the health risks to school-going *** described that the As concentration ranged between 0.002 and 0.994 mg L^(-1)with an average value of 0.044 mg L^(-1);which exceeded the World Health Organization(WHO)provisional guideline value of 0.01 mg L^(-1).Similarly,the Fe content varied from 0.05 to 10 mg L^(-1)averaging to 2.84 mg L^(-1).Samples of 55.17%contained a greater As concentration than0.01 mg L^(-1)and 18.97%greater than Bangladesh drinking water quality(BDWQ)standard of 0.05 mg L^(-1),***,75.86%of samples contained a higher Fe concentration than the maximum Bangladesh permissible limit of 1 mg L^(-1).Health risk assessment indicated that girls are more vulnerable than boys *** average hazard quotients(HQs)for As intake through drinking water were 6.01±17.85 and 7.41±22.03 for boys and girls,respectively,implying non-carcinogenic health risks to both *** HQs for Fe intake were less than threshold value of 1 indicating no health issues may arise from Fe intake ***,consumption of As and Fe may trigger health risks to students as indicated by the hazard index(HI),which was higher than *** average cancer risk(CR)values for both boys(0.0027±0.008)and girls(0.0033±0.0099)exceeded the threshold limit of 10-6-10-4,suggesting a possibility of lifetime cancer risks to the school-going ***,school authorities should find alternative ways to ensure safe drinking water for school-going children to avoid possible cancer and non-cancer health risks through consumption of As-poisoning water.

关键词： Arsenic Iron Human health risks Groundwater

A Review of the Study on the Electromigration and Power Electronics

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Journal of Electronics Cooling and Thermal Control 2016年第1期6卷 19-31页

作者： md. khalilur rahman Abul Monsur Mohammed Musa Budrun Neher Kawchar Ahmed Patwary Mohammad Atiqur rahman md. Shariful Islam Department of Physics Comilla University Comilla Bangladesh Department of Physics University of Chittagong Chittagong Bangladesh Department of Chemistry Comilla University Comilla Bangladesh Department of ICT Comilla University Comilla Bangladesh

Electromigration is a main challenge in the pursuit of power electronics, because physical limit to increase current density in power electronics is electromigration (EM), whereas much higher electrical current and voltage are required for power electronics packaging. So the effect of EM is an important issue in applications where high current densities are used, such as in microelectronics and related structures (e.g., Power ICs). Since the structure size of integrated circuits (ICs) decreases and the practical significance of this effect increases, the result is EM failure. On the other hand, in the next generation power electronics technology electrical current density is expected to exceed 107 A/cm2 which is another challenge. This review work has been carried out to identify the mechanism of EM damage in power electronics (e.g., pure metallization and solder joints) and also how to control this kind of damage.

关键词： Voids and Hillocks Interconnect Solder Joint Thermomigration MTF Reliability of IC

Ensemble learning of diffractive optical networks

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Light(Science & Applications) 2021年第1期10卷 123-135页

作者： md Sadman Sakib rahman Jingxi Li Deniz Mengu Yair Rivenson Aydogan Ozcan Electrical and Computer Engineering Department University of CaliforniaLos AngelesCA 90095USA Bioengineering Department University of CaliforniaLos AngelesCA 90095USA California NanoSystems Institute(CNSI) University of CaliforniaLos AngelesCA 90095USA

A plethora of research advances have emerged in the fields of optics and photonics that benefit from harnessing the power of machine ***,there has been a revival of interest in optical computing hardware due to its potential advantages for machine learning tasks in terms of parallelization,power efficiency and computation *** deep neural networks(D^(2)NNs)form such an optical computing framework that benefits from deep learning-based design of successive diffractive layers to all-optically process information as the input light diffracts through these passive layers.D^(2)NNs have demonstrated success in various tasks,including object classification,the spectral encoding of information,optical pulse shaping and ***,we substantially improve the inference performance of diffractive optical networks using feature engineering and ensemble *** independently training 1252 D^(2)NNs that were diversely engineered with a variety of passive input filters,we applied a pruning algorithm to select an optimized ensemble of D^(2)NNs that collectively improved the image classification *** this pruning,we numerically demonstrated that ensembles of N=14 and N=30 D^(2)NNs achieve blind testing accuracies of 61.14±0.23%and 62.13±0.05%,respectively,on the classification of GFAR-10 test images,providing an inference improvennent of>16%compared to the average performance of the individual D^(2)NNs within each *** results constitute the highest inference accuracies achieved to date by any diffractive optical neural network design on the same dataset and might provide a significant leap to extend the application space of diffractive optical image classification and machine vision systems.

关键词： networks collective successive

An efficient hybrid system for anomaly detection in social networks

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Cybersecurity 2021年第1期4卷 136-146页

作者： md.Shafiur rahman Sajal Halder mdAshraf Uddin Uzzal Kumar Acharjee Department of Computer Science and Engineering Dhaka International UniversityDhakaBangladesh Department of Computer Science and Engineering Jagannath UniversityDhakaBangladesh Department Computer Science and Information Technology RMIT UniversityMelbourneAustralia Internet Commerce Security Laboratory Federation University AustraliaBallarat VIC 3350Australia

Anomaly detection has been an essential and dynamic research area in the data mining.A wide range of applications including different social medias have adopted different state-of-the-art methods to identify anomaly for ensuring user’s security and *** social network refers to a forum used by different groups of people to express their thoughts,communicate with each other,and share the content *** social networks also facilitate abnormal activities,spread fake news,rumours,misinformation,unsolicited messages,and propaganda post malicious ***,detection of abnormalities is one of the important data analysis activities for the identification of normal or abnormal users on the social *** this paper,we have developed a hybrid anomaly detection method named DT-SVMNB that cascades several machine learning algorithms including decision tree(C5.0),Support Vector Machine(SVM)and Naïve Bayesian classifier(NBC)for classifying normal and abnormal users in social *** have extracted a list of unique features derived from users’profile and *** two kinds of dataset with the selected features,the proposed machine learning model called DT-SVMNB is *** model classifies users as depressed one or suicidal one in the social *** have conducted an experiment of our model using synthetic and real datasets from social *** performance analysis demonstrates around 98%accuracy which proves the effectiveness and efficiency of our proposed system.

关键词： Anomaly Detection Machine Learning Hybrid Anomaly Detection Social Networks

Antioxidant,antibacterial and cytotoxic effects of the phytochemicals of whole Leucas aspera extract

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Asian Pacific Journal of Tropical Biomedicine 2013年第4期3卷 273-279页

作者： md Atiar rahman md Saiful Islam Department of Biochemistry and Molecular Biology University of ChittagongChittagong-4331Bangladesh Department of Biochemistry School of BiochemistryGenetics and MicrobiologyUniversity of KwaZulu-Natal.(Westville Campus)Durban 4000South Africa

Objective:To investigate the antioxidant,antibacterial and cytotoxic activity of whole Leucas aspera(Labiatae)(***)alcoholic ***:Whole *** powder was extracted by absolute ethanol(99.50%).The ethanolic extract was subjected to antioxidant,antibacterial and brine shrimp lethality ***:The extract showed potent radical scavenging effect(antioxidant)with IC_(50)value of(99.58±1.22)μg/mL which was significant(P<0.01)in comparison to ascorbic acid with IC_(50)value of(1.25±0.95)μg/*** case of antibacterial screening,the extract showed notable antibacterial effect against the tested microbial ***(P<0.05)zone of inhibitions against Gram positive Bacillus subtilis[(12.00±1.32)mm]and Bacillus megaterium[(13.00±1.50)mm],Staphylococcus aureus[(8.00±0.50)mm]and Gram negative Salmonella typhi[(6.00±0.50)mm],Salmonella paratyphi[(8.00±1.00)mm],Shigella dysenteriae[(9.00±1.32)mm]and Vibrio cholerae[(9.00±0.66)mm]was *** brine shrimp lethality bioassay,the extract showed the LC_(50)value as(181.68±2.15)μg/mL which was statistically significant(P<0.01)compared to positive control vincristine sulfate[LC_(50)=(0.76±0.04)μg/mL].Conclusions:The results demonstrate that the ethanolic extract of *** could be used as antibacterial,pesticidal and various pharmacologic actives.

关键词： Leucas aspera Radical scavenging Antibacterial Cytotoxic Probit

Industrial IoT Based Condition Monitoring for Wind Energy Conversion System

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CSEE Journal of Power and Energy Systems 2021年第3期7卷 654-664页

作者： md Liton Hossain Ahmed Abu-Siada S.M.Muyeen md Mubashwar Hasan Momtazur rahman Department of Electrical and Computer Engineering Curtin UniversityPerthAustralia School of Science Engineering and ITFederation UniversityAustralia Edith Cowan University Australia

Wind energy has been identified as the second dominating source in the world renewable energy generation after *** and distribution of wind energy has brought technology revolution by developing the advanced wind energy conversion system(WECS)including multilevel inverters(MLIs).The conventional rectifier produces ripples in their output waveforms while the MLI suffers from voltage balancing issues across the DC-link *** paper proposes a simplified proportional integral(PI)-based space vector pulse width modulation(SVPWM)to minimize the output waveform ripples,resolve the voltage balancing issue and produce better-quality output *** experiences various types of faults particularly in the DC-link capacitor and switching devices of the power *** faults,if not detected and rectified at an early stage,may lead to catastrophic failures to the WECS and continuity of the power *** paper proposes a new algorithm embedded in the proposed PI-based SVPWM controller to identify the fault location in the power converter in real *** most wind power plants are located in remote areas or offshore,WECS condition monitoring needs to be developed over the internet of things(IoT)to ensure system *** this paper,an industrial IoT algorithm with an associated hardware prototype is proposed to monitor the condition of WECS in the real-time environment.

关键词： Asset management condition monitoring fault diagnosis industrial internet of things(IoT) wind energy conversion system

Assessment of Physico-Chemical and Microbial Quality of Sugarcane Juice Sold by Street Vendors in Three Regions of Bangladesh

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Analysis and modeling of hysteresis of piezoelectric micro-actuator used in high precision dual-stage servo system

Food and Nutrition Sciences（食品与营养科学） 2024年第4期 263页

作者： Nargis Akter Khan md. Murtaja Reza Linkon Munni Akter md. Alamgir Hossain md. Mahbubur rahman Tayeba Khan md. Abdul Alim md. Esrafil

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Control Theory and Technology 2015年第2期13卷 184-203页

作者： md.Arifur rahman Abdullah Al MAMUN Kui YAO Department of Electrical and Computer Engineering National University of Singapore Institute of Materials Research and EngineeringA*STAR (Agency for Science Technology and Research)

A dual-stage servo system consists of a primary coarse actuator for facilitating large motion and a secondary micro-actuator for small but precise motion to improve tracking performance. Piezoelectric micro-actuator made from lead zirconate titanate(PZT)has been a popular choice for the secondary stage. However, the advantage gained by the resolution of the secondary PZT actuator is reduced by its inherent hysteresis nonlinearity. Model based hysteresis compensation techniques are preferred due to their simplicity and fast response. Identification and modeling are two substantial parts in such model-based techniques. This paper presents a rigorous analysis and modeling of the hysteresis of PZT micro-actuator. Modified Generalized Prandtl-Ishlinskii and Coleman-Hodgdon models are studied. Identification of the model through nonlinear least square and particle swarm optimization are examined and compared. Several analyses are done through tuning of the model parameters and identification *** analysis and simulation results underscore the effectiveness of this modeling approach. Finally as a design example,a dual-stage simulation analysis is done to show the effectiveness of systematic modeling on hysteresis compensation.

关键词： Hysteresis particle swarm optimization(PSO) modified generalized Prandtl-Ishlinskii(GPI) inverse GPI

Effect of Exchange-Correlation Functional on the Structural, Mechanical, and Optoelectronic Properties of Orthorhombic RbSrBr3 Perovskite

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