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Extraction and characterization of alumina nanopowders from aluminum dross by acid dissolution process

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International Journal of Minerals,Metallurgy and Materials 2015年第4期22卷 429-436页

作者： saifur rahman Sarker Zahangir Alam Rakibul Qadir M A Gafur Mohammad Moniruzzaman Department of Applied Chemistry and Chemical Engineering University of Dhaka Pilot Plant & Project Development Centre (PP& PDC) Bangladesh Council of Scientific and Industrial Research (BCSIR) BCSIR Laboratories Dhaka

A significant amount of aluminum dross is available as a waste in foundry industries in Bangladesh. In this study, alumina was ex- tracted from aluminum dross collected from two foundry industries situated in Dhamrai and Manikgang, near the capital city, Dhaka. Alu- minum dross samples were found to approximately contain 75wt% A1203 and 12wt% SIO2. An acid dissolution process was used to recover the alumina value from the dross. The effects of various parameters, e.g., temperature, acid concentration, and leaching time, on the extrac- tion of alumina were studied to optimize the dissolution process. First, AI（OH）3 was produced in the form of a gel. Calcination of the AI（OH）3 gel at 1000℃, 1200℃, and 1400℃ for 2 h produced O-AlcOa, （t~＋O）-A1203, and u-alumina powder, respectively. Thermal charac- terization of the AI（OH）3 gel was performed by thermogravimetric/differential thermal analysis （TG/DTA） and differential scanning calo- rimetry （DSC）. The phases and crystallite size of the alumina were determined by X-ray diffraction analysis. The dimensions of the alumina were found to be on the nano level. The chemical compositions of the aluminum dross and alumina were determined by X-ray fluorescence （XRF） spectroscopy. The microstructure and morphology of the alumina were studied with scanning electron microscopy. The purity of the alumina extracted in this study was found to be 99.0%. Thus, it is expected that the obtained alumina powders can be potentially utilized as biomaterials.

关键词： aluminum dross alumina nanoparticles acid dissolution calcination X-ray fluorescence analysis

Agent-based Modeling and Simulation for the Electricity Market with Residential Demand Response

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CSEE Journal of Power and Energy Systems 2021年第2期7卷 368-380页

作者： Shuyang Xu Xingying Chen Jun Xie saifur rahman Jixiang Wang Hongxun Hui Tao Chen College of Energy and Electrical Engineering Hohai UniversityNanjing 211100China Department of Electrical and Computer Engineering Viginia TechAlington VA 22203 USAand also with the Advanced Research InstituteViginia TechArlingtonVA 22203 USA State Key Laboratory of Internet of Things for Smart City University of MacaoMacao 519031China Collegue of Electrical Engineering Southeast UniversityNanjing 210009China.DOI:10.17775/CSEEJPES.2019.01750

Currently,critical peak load caused by residential customers has attracted utility companies and policymakers to pay more attention to residential demand response(RDR)*** typical RDR programs,residential customers react to the price or incentive-based signals,but the actions can fall behind flexible market *** those residential customers equipped with smart meters,they may contribute more DR loads if they can participate in DR events in a proactive *** this paper,we propose a comprehensive market framework in which residential customers can provide proactive RDR actions in a day-ahead market(DAM).We model and evaluate the interactions between generation companies(GenCos),retailers,residential customers,and the independent system operator(ISO)via an agent-based modeling and simulation(ABMS)*** simulation framework contains two main procedures—the bottom-up modeling procedure and the reinforcement learning(RL)*** bottom-up modeling procedure models the residential load profiles separately by household types to capture the RDR potential differences in advance so that residential customers may rationally provide automatic DR *** and GenCos optimize their bidding strategies via the RL *** modified optimization approach in this procedure can prevent the training results from falling into local optimum *** ISO clears the DAM to maximize social welfare via Karush-Kuhn-Tucker(KKT)*** on realistic residential data in China,the proposed models and methods are verified and compared in a large multi-scenario test case with 30,000 residential *** show that proactive RDR programs and interactions between market entities may yield significant benefits for both the supply and demand *** models and methods in this paper may be used by utility companies,electricity retailers,market operators,and policy makers to evaluate the consequences of a proactive RDR and the interactions

关键词： Agent-based modeling and simulation(ABMS) electricity market residential demand response(RDR) reinforcement learning(RL)

Utilization of Energy Storage and Hydrogen in Power and Energy Systems:Viewpoints from Five Aspects

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CSEE Journal of Power and Energy Systems 2023年第1期9卷 1-7页

作者： Yonghua Song Mohammad Shahidehpour saifur rahman Nigel Brandon Kai Strunz Jin Lin Yuxuan Zhao State Key Laboratory of Internet of Things for Smart City University of MacaoTaipaMacao 999078China Department of Electrical Engineering Tsinghua UniversityBeijing 100084China Galvin Center for Electricity Innovation Illinois Institute of TechnologyChicagoIL 60616USA Department of Advanced Research Institute Virginia Polytechnic Institute and State UniversityArlingtonVA 22203USA Department of Earth Science and Engineering Imperial College LondonLondon SW72AZU.K Department of Sustainable Electric Networks and Sources of Energy Technische Universitt Berlin10587 BerlinGermany State Key Laboratory of Control and Simulation of Power Systems and Generation Equipment Department of Electrical EngineeringTsinghua UniversityBeijing 100084China

Decarbonizing power systems is crucial to mitigating climate change impacts and achieving carbon *** renewable energy supply can reduce greenhouse gas emissions and accelerate the decarbonization ***,renewable energy sources(RESs)such as wind and solar power are characterized by intermittency and often non-dispatchability,significantly challenging their high-level integration into power *** storage is acknowledged as a vital indispensable solution for mitigating the intermittency of renewables such as wind and solar power and boosting the penetrations of *** the CSEE JPES Forum,five well-known experts were invited to give keynote speeches,and the participating experts and scholars had comprehensive exchanges and discussions on energy storage ***,the views on the design,control,performance,and applications of new energy storage technologies,such as the fuel cell vehicle,water electrolysis,and flow battery,in the coordination and operation of power and energy systems were *** experts also provided experience that could be used to develop energy storage for constructing and decarbonizing new power systems.

关键词： Electrolysis electric vehicle energy storage flow battery fuel cell electric vehicle hydrogen energy

大规模风电接入对美国电力系统运行的影响和平抑策略(英文)

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电力系统自动化 2011年第22期35卷 3-11页

作者： saifur rahman Manisa PIPATTANASOMPORN Advanced Research Institute Virginia Polytechnic Institute and State University

至2010年底,美国的风电装机容量仅次于中国,居世界第二。考虑政府的支持政策和可观的风资源储量,有专家预见,未来美国40%的电能可来自于风力发电。在详细分析大规模风电接入对美国电力系统运行产生的影响的基础上,文中提出了需应对的几... 详细信息

至2010年底,美国的风电装机容量仅次于中国,居世界第二。考虑政府的支持政策和可观的风资源储量,有专家预见,未来美国40%的电能可来自于风力发电。在详细分析大规模风电接入对美国电力系统运行产生的影响的基础上,文中提出了需应对的几个方面的挑战。分析结果显示,最关键的挑战来自于风电功率的波动特性,可将其转化为系统负荷减去风电出力后的净负荷波动特性。随后文章提出了已被实际应用或正在工程示范的几种电网级储能方式来平抑风电接入给电网带来的负面影响。文中也对电网级储能方式对传统发电厂利用因子的影响加以讨论。

关键词：风力发电大规模风电接入负荷持续曲线基荷发电厂电网级储能方式

Coupon-based Demand Response for Consumers Facing Flat-rate Retail Pricing

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CSEE Journal of Power and Energy Systems 2024年第5期10卷 1887-1900页

作者： Hongxun Hui Yi Ding Kaining Luan Tao Chen Yonghua Song saifur rahman State Key Laboratory of Internet of Things for Smart City and the Department of Electrical and Computer Engineering University of MacaoMacao 999078China. College of Electrical Engineering Zhejiang UniversityHangzhou 310027China State Grid Jiangsu Electric Power Co. LTD.Nanjing 210000China School of Electrical Engineering Southeast UniversityNanjing 210096China Advanced Research Institute and Department of Electrical and Computer Engineering Virginia Polytechnic Institute and State UniversityVA 22203USA

Even though smart meters have been widely used in power systems around the world,many consumers are still finding it hard to participate in demand response(DR)due to flat-rate retail pricing *** address this issue,this paper proposes a coupon-based demand response(CDR)scheme to achieve equivalent dynamic retail prices to inspire consumers’inherent ***,a security-constrained unit commitment optimization model is developed in the day-ahead market to obtain coupon rewards,which are then broadcast to consumers to motivate them to reschedule their power consumption *** evaluate the adjustment value of consumers’power consumption,a collective utility function is proposed to formulate the relationship between power quantity and coupon *** this basis,the security-constrained economic dispatch model is developed in the intra-day market to reschedule generating units’output power according to real-time load demands and fluctuating renewable *** the operation interval,a settlement method is developed to quantify consumers’electricity fees and coupon benefits on a monthly *** proposed CDR scheme avoids real-time iterative bidding process and effectively decreases the difficulty of massive,small consumers participating in *** proposed CDR is implemented in a realistic DR project in China to verify consumers’energy cost and renewables’curtailment can both be decreased.

关键词： Coupons demand response flat-rate retail pricing renewable energies small consumers

Low Altitude Satellite Constellation for Futuristic Aerial-Ground Communications

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Computer Modeling in Engineering & Sciences 2023年第8期136卷 1053-1089页

作者： saifur rahman Sabuj Mohammad Saadman Alam Majumder Haider Md Akbar Hossain Al-Sakib Khan Pathan Department of Electronic Engineering Hanbat National UniversityDaejeon34158South Korea Department of Electrical and Electronic Engineering Brac UniversityDhaka1212Bangladesh School of Business and Digital Technologies Manukau Institute of TechnologyManukau2241New Zealand Department of Computer Science and Engineering United International UniversityDhaka1212Bangladesh

This paper discusses the significance and prospects of low altitude small satellite aerial vehicles to ensure smooth aerial-ground communications for next-generation broadband *** achieve the generic goals of fifthgeneration and beyondwireless networks,the existing aerial network architecture needs to be *** detailed architecture of low altitude aerial networks and the challenges in resource management have been illustrated in this ***,we have studied the coordination between promising communication technologies and low altitude aerial networks to provide robust network *** talk about the techniques that can ensure userfriendly control and monitoring of the low altitude aerial networks to bring forth wireless broadband connectivity to a new *** the end,we highlight the future research directions of aerial-ground communications in terms of access technologies,machine learning,compressed sensing,and quantum communications.

关键词： Aerial-terrestrial network cognitive radio network cooperative communication high altitude platform low altitude platform low earth orbit satellite constellation unmanned aerial vehicle

Broadband mechanoresponsive liquid metal sensors

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npj Flexible Electronics 2022年第1期6卷 718-725页

作者： Md saifur rahman Julia E.Huddy Andrew B.Hamlin William J.Scheideler Thayer School of Engineering Dartmouth CollegeHanoverNH 03755USA

Stretchable electronics have the fundamental advantage of matching the complex geometries of the human body,providing opportunities for real-time biomechanical *** report a method for high-frequency AC-enhanced resistive sensing that leverages deformable liquid metals to improve low-power detection of mechanical stimuli in wearable *** fundamental mechanism of this enhancement is geometrical modulation of the skin effect,which induces current crowding at the surface of a liquid metal *** combination with DC sensing,this method quantitatively pinpoints mechanical modes of deformation such as stretching in-plane and compression out-of-plane that are traditionally impossible to *** we explore this method by finite element simulations then employ it in a glove to detect hand gestures and tactile forces as well as a respiratory sensor to measure ***,this AC sensor uses lower power(100X)than DC sensors,enabling a new generation of energy-efficient wearables for haptics and biomedical sensing.

关键词： wear deformation liquid

Moldable and transferrable conductive nanocomposites for epidermal electronics

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npj Flexible Electronics 2022年第1期6卷 363-371页

作者： Myeong Namkoong Heng Guo Md saifur rahman Daniel Wang Cassandra Jane Pfeil Sophia Hager Limei Tian Department of Biomedical Engineering and Center for Remote Health Technologies and SystemsTexas A&M UniversityCollege StationTX 77843USA

Skin-inspired soft and stretchable electronic devices based on functional nanomaterials have broad applications such as health monitoring,human-machine interface,and the Internet of ***-processed conductive nanocomposites have shown great promise as a building block of soft and stretchable electronic ***,realizing conductive nanocomposites with high conductivity,electromechanical stability,and low modulus over a large area at sub-100μm resolution remains ***,we report a moldable,transferrable,high-performance conductive nanocomposite comprised of an interpenetrating network of silver nanowires and poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate).The stacked structure of the nanocomposite synergistically integrates the complementary electrical and mechanical properties of the individual *** patterned the nanocomposite via a simple,low-cost micromolding process and then transferred the patterned large-area electrodes onto various substrates to realize soft,skin-interfaced electrophysiological *** signals measured using the nanocomposite electrodes exhibit a higher signal-to-noise ratio than standard gel *** nanocomposite design and fabrication approach presented here can be broadly employed for soft and stretchable electronic devices.

关键词： conductive transfer interface

Automatic Detection of Outliers in Multi-Channel EMG Signals Using MFCC and SVM

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Intelligent Automation & Soft Computing 2023年第4期36卷 169-181页

作者： Muhammad Irfan Khalil Ullah Fazal Muhammad Salman Khan Faisal Althobiani Muhammad Usman Mohammed Alshareef Shadi Alghaffari saifur rahman Electrical Engineering Department College of EngineeringNajran University Saudi ArabiaNajran61441Saudi Arabia Department of Software Engineering University of MalakandDir LowerPakistan Department of Electrical Engineering University of Engineering and TechnologyMardan23200Pakistan Faculty of Maritime Studies King Abdulaziz UniversityJeddah21589Saudi Arabia Department of Computer Science University of Engineering and TechnologyMardan23200Pakistan

The automatic detection of noisy channels in surface Electromyogram(sEMG)signals,at the time of recording,is very critical in making a noise-free EMG *** an EMG signal contaminated by high-level noise is recorded,then it will be useless and can’t be used for any healthcare *** this research work,a new machine learning-based paradigm is proposed to automate the detection of low-level and high-level noises occurring in different channels of high density and multi-channel sEMG signals.A modiﬁed version of mel fre-quency cepstral coefﬁcients(mMFCC)is proposed for the extraction of features from sEMG channels along with other statistical parameters i-e complexity coef-ﬁcient,hurst exponent,and root mean *** state-of-the-art classiﬁers such as Support Vector Machine(SVM),Ensemble Bagged Trees,Ensemble Sub-space Discriminant,and Logistic Regression are used to automatically identify an EMG channel either bad or good based on these extracted ***-based analyses of these classiﬁers have also been considered based on total classi-ﬁcation accuracy,prediction speed(observations/sec),and processing *** proposed method is tested on 320 simulated EMG channels as well as 640 experi-mental EMG *** is used as our main classiﬁer for the detection of noisy channels which gives a total classiﬁcation accuracy of 99.4%for simulated EMG channels whereas accuracy of 98.9%is achieved for experimental EMG channels.

关键词： Machine learning surface electromyography support vector machine classiﬁcation features