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Warped time lens in temporal imaging for optical real-time data compression

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Chinese Science Bulletin 2014年第22期59卷 2649-2654页

作者： Mohammad H.Asghari bahram jalali Department of Electrical Engineering University of California Los Angeles CA 90095 USA Department of Bioengineering University of CaliforniaLos Angeles CA 90095 USA Department of Surgery David Geffen School of MedicineUniversity of California Los Angeles CA 90095 USA

We introduce for the first time the concept of anamorphic temporal imaging and its application to analog data compression in a time *** in front of a conventional spectrometer,this technique enhances the spectral resolution and the update *** importantly,it performs real-time optical data compression to reduce the volume of the generated digital *** technique introduces the concept of the warped time *** show that a specific class of warped time-to-frequency mapping operations combined with the nonlinear operation inherent in a photo-detector compresses the time-bandwidth product in a temporal imaging *** employ our newly introduced Stretched Modulation Distribution to design the warp *** this method,the narrow spectral features beyond the spectrometer resolution can be captured and at the same time the output bandwidth and hence the record length is *** reduction in the record length results in higher update rate for the spectrometer without sacrificing the spectral resolution or *** method also benefits from amplitude and phase detection to recover the input complex-field *** compressing the time-bandwidth product,anamorphictemporal imaging addresses the Big Data problem in such high-throughput instruments.

关键词：数据压缩成像系统扭曲实时光学光谱分辨率时间带宽积变形时间

Phase Diversity Electro-optic Sampling:A new approach to single-shot terahertz waveform recording

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Light(Science & Applications) 2022年第1期11卷 87-100页

作者： Eléonore Roussel Christophe Szwaj Clément Evain Bernd Steffen Christopher Gerth bahram jalali Serge Bielawski Univ.Lille CNRSUMR 8523-PhLAM-Physique des LasersAtomes et MoléculesCentre d’Étude Recherches et Applications(CERLA)F-59000 LilleFrance DESY(Deutsches Elektronen-Synchrotron) Notkestr.85D-22607 HamburgGermany Electrical and Computer Engineering Department University of CaliforniaLos Angeles420 Westwood Plaza90095 Los AngelesCAUSA

Recording electric field evolution in single-shot with THz bandwidth is needed in science including spectroscopy,plasmas,biology,chemistry,Free-Electron Lasers,accelerators,and material ***,the potential application range depends on the possibility to achieve sub-picosecond resolution over a long time window,which is a largely open problem for single-shot *** solve this problem,we present a new conceptual approach for the so-called spectral decoding technique,where a chirped laser pulse interacts with a THz signal in a Pockels crystal,and is analyzed using a grating optical spectrum *** borrowing mathematical concepts from photonic time stretch theory and radio-frequency communication,we deduce a novel dual-output electro-optic sampling system,for which the input THz signal can be numerically retrieved—with unprecedented resolution—using the so-called phase diversity *** show numerically and experimentally that this approach enables the recording of THz waveforms in single-shot over much longer durations and/or higher bandwidth than previous spectral decoding *** present and test the proposed DEOS(Diversity Electro-Optic Sampling)design for recording 1.5 THz bandwidth THz pulses,over 20 ps duration,in *** we demonstrate the potential of DEOS in accelerator physics by recording,in two successive shots,the shape of 200 fs RMS relativistic electron bunches at European X-FEL,over 10 ps recording *** designs presented here can be used directly for accelerator diagnostics,characterization of THz sources,and single-shot Time-Domain Spectroscopy.

关键词： recording approach successive

Federated Learning Security and Privacy-Preserving Algorithm and Experiments Research Under Internet of Things Critical Infrastructure

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Tsinghua Science and Technology 2024年第2期29卷 400-414页

作者： Nasir Ahmad jalali Hongsong Chen Department of Computer Science University of Science and Technology Beijing(USTB)Beijing 100083China

The widespread use of the Internet of Things(IoTs)and the rapid development of artificial intelligence technologies have enabled applications to cross commercial and industrial band *** such systems,all participants related to commercial and industrial systems must communicate and generate ***,due to the small storage capacities of IoT devices,they are required to store and transfer the generated data to third-party entity called“cloud”,which creates one single point to store their ***,as the number of participants increases,the size of generated data also ***,such a centralized mechanism for data collection and exchange between participants is likely to face numerous challenges in terms of security,privacy,and *** address these challenges,Federated Learning(FL)has been proposed as a reasonable decentralizing approach,in which clients no longer need to transfer and store real data in the central ***,they only share updated training models that are trained over their private *** the same time,FL enables clients in distributed systems to share their machine learning models collaboratively without their training data,thus reducing data privacy and security ***,slow model training and the execution of additional unnecessary communication rounds may hinder FL applications from operating properly in a distributed ***,these unnecessary communication rounds make the system vulnerable to security and privacy issues,because irrelevant model updates are sent between clients and ***,in this work,we propose an algorithm for fully homomorphic encryption called Cheon-Kim-Kim-Song(CKKS)to encrypt model parameters for their local information privacy-preserving *** proposed solution uses the impetus term to speed up model convergence during the model training ***,it establishes a secure communication channel between IoT devices and the *** a

关键词： Federated Learning(FL) Internet of Things(IoTs) lightweight Transport Layer Security(iTLS) Cheon-Kim-Kim-Song(CKKS)

Prediction of vertical displacement for a buried pipeline subjected to normal fault using a hybrid FEM-ANN approach

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 428-443页

作者： Hedye jalali Reza YEGANEH KHAKSAR Danial MOHAMMADZADEH S. Nader KARBALLAEEZADEH Amir H.GANDOMI Department of Civil Engineering Architecture and UrbanismSadjad University of TechnologyPO Box ***MashhadIran Department of Civil Engineering Faculty of EngineeringEqbal Lahoori Institute of Higher EducationPO Box ***MashhadIran Faculty of Civil Engineering Architectureand ArtScience and Research Branch of Islamic Azad UniversityPO Box ***TehranIran Faculty of Engineering&Information Technology University of Technology SydneyUltimoNSW 2007Australia University Research and Innovation Center(EKIK) Óbuda UniversityBudapest 1034Hungary

Fault movement during earthquakes is a geotechnical phenomenon threatening buried pipelines and with the potential to cause severe damage to critical ***,effective prediction of pipe displacement is crucial for preventive management *** study aims to develop a fast,hybrid model for predicting vertical displacement of pipe networks when they experience *** this study,the complex behavior of soil and a buried pipeline system subjected to a normal fault is analyzed by using an artificial neural network(ANN)to generate predictions the behavior of the soil when different parameters of it are *** this purpose,a finite element model is developed for a pipeline subjected to normal fault *** data bank used for training the ANN includes all the critical soil parameters(cohesion,internal friction angle,Young’s modulus,and faulting).Furthermore,a mathematical formula is presented,based on biases and weights of the ANN *** results show that the maximum error of the presented formula is 2.03%,which makes the proposed technique efficiently predict the vertical displacement of buried pipelines and hence,helps to optimize the upcoming pipeline projects.

关键词： buried pipelines normal Fault finite element method multilayer perceptron neural network formulation

用机械涂层技术在Ti-6Al-4V基体表面沉积HA/Ti复合涂层与功能梯度涂层的表征、磨损行为和生物相容性

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Transactions of Nonferrous Metals Society of China 2024年第2期34卷 547-559页

作者： Mahmood jalali BIDAKHAVIDI Hamid OMIDVAR Ali ZAMANIAN Jamshid AGHAZADEH MOHANDESI Hamid jalali Department of Materials and Metallurgical Engineering Amirkabir University of Technology(Tehran Polytechnic)Hafez AveP.O.Box 15875-4413TehranIran Department of Nanotechnology and Advanced Materials Materials and Energy Research CenterKarajIran School of Dentistry Tehran University of Medical SciencesTehranIran

采用机械涂层技术在Ti-6Al-4V基体表面沉积HA/Ti复合涂层与功能梯度涂层(FGC),对涂层进行表征,对比其磨损行为和生物相容性。制备复合涂层所用初始粉末为50%Ti(质量分数)和50%HA(质量分数)的混合粉末,而FGC分为两层,分别为75%Ti+25%HA和... 详细信息

采用机械涂层技术在Ti-6Al-4V基体表面沉积HA/Ti复合涂层与功能梯度涂层(FGC),对涂层进行表征,对比其磨损行为和生物相容性。制备复合涂层所用初始粉末为50%Ti(质量分数)和50%HA(质量分数)的混合粉末,而FGC分为两层,分别为75%Ti+25%HA和25%Ti+75%HA(质量分数)。XRD结果表明在沉积过程中没有发生相变。此外,由于原始混合粉末中存在Ti颗粒,在涂层和基体之间形成了结合良好的连续界面,特别是在功能梯度涂层样品中。磨损实验结果显示,非梯度复合涂层的摩擦因数约为0.37,在界面处发生突变,而功能梯度涂层的摩擦因数从0.32增加到0.5,在界面处发生平缓变化。磨损表面的SEM像表明涂层的主要磨损机制为磨粒磨损。生物相容性评价结果显示,FGC样品具有更好的细胞黏附和增殖能力。

关键词：机械涂层技术羟基磷灰石 Ti-6Al-4V基体功能梯度涂层摩擦因数

Erratum to:Exciton recycling via InP quantum dot funnels for luminescent solar concentrators

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Nano Research 2024年第6期17卷 5756-5756页

作者： Houman Bahmani jalali Sadra Sadeghi Isinsu Baylam Mertcan Han Cleva W.Ow-Yang Alphan Sennaroglu Sedat Nizamoglu Graduate School of Biomedical Sciences and Engineering Koc UniversityIstanbul 34450Turkey Graduate School of Material Science and Engineering Koc UniversityIstanbul 34450Turkey Koc University Surface Science and Technology Center(KUYTAM) Koc UniversityIstanbul 34450Turkey Laser Research Laboratory Koc UniversityIstanbul 34450Turkey Department of Electrical and Electronics Engineering Koc UniversityIstanbul 34450Turkey Department of Material Science and Nano Engineering Sabanci UniversityIstanbul 34956Turkey

The article“Exciton recycling via InP quantum dot funnels for luminescent solar concentrators”written by Houman Bahmani jalali,Sadra Sadeghi,Isinsu Baylam,Mertcan Han,Cleva ***-Yang,Alphan Sennaroglu,and Sedat Nizamoglu,was originally published Online First without Open *** publication online first,the author decided to opt for Open Choice and to make the article an Open Access ***,the copyright of the article has been changed to©The Author(s)2020 and the article is forthwith distributed under the terms of the Creative Commons Attribution 4.0 International License(http://***/licenses/by/4.0/),which permits use,duplication,adaptation,distribution and reproduction in any medium or format,as long as you give appropriate credit to the original author(s)and the source,provide a link to the Creative Commons license,and indicate if changes were *** original article has been corrected.

关键词： quantum Open license

Ductility improvement of GFRP-RC beams using precast confined concrete block in compression zone

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Frontiers of Structural and Civil Engineering 2023年第10期17卷 1585-1598页

作者： Nooshin G.AMIRABAD Farshid J.ALAEE Meysam jalali Civil Engineering Department Shahrood University of TechnologyShahrood ***Iran

Fiber-reinforced polymers(FRPs)have received considerable research attention because of their high strength,corrosion resistance,and low ***,owing to the lack of ductility in this material and the quasi-brittle behavior of concrete,FRP-reinforced concrete(FRP-RC)beams,even with flexural failure,do not fail in a ductile *** the limited deformation capacity of FRP-RC beams depends on the ductility of their compression zones,the present study proposes using a precast confined concrete block(PCCB)in the compression zone to improve the ductility of the beams.A control beam and four beams with different PCCBs were cast and tested under four-point bending *** control beam failed due to shear,and the PCCBs exhibited different confinements and *** goal was to find an appropriate PCCB for use in the compression zone of the beams,which not only improved the ductility but also changed the failure mode of the beams from shear to *** the employed blocks,a ductile PCCB with low equivalent compressive strength increased the ductility ratio of the beam to twice that of the control *** beam failed in pure flexure with considerable deformation capacity and without significant stiffness reduction.

关键词： ductility four-point bending test glass fiber-reinforced polymer precast confined concrete block

An Efficient Hybrid Model Based on Modified Whale Optimization Algorithm and Multilayer Perceptron Neural Network for Medical Classification Problems

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Journal of Bionic Engineering 2022年第5期19卷 1504-1521页

作者： Saeid Raziani Sajad Ahmadian Seyed Mohammad Jafar jalali Abdolah Chalechale Department of Computer Engineering Razi UniversityKermanshah ***Iran Faculty of Information Technology Kermanshah University of TechnologyKermanshah ***Iran Institute for Intelligent Systems Research and Innovation(IISRI) Deakin UniversityWaurn PondsMelbourne 3217Australia

Feedforward Neural Network(FNN)is one of the most popular neural network models that is utilized to solve a wide range of nonlinear and complex *** models such as stochastic gradient descent have been developed to train ***,they mainly suffer from falling into local optima leading to reduce the accuracy of ***,the convergence speed of training process depends on the initial values of weights and biases in ***,these values are randomly determined by most of the training *** deal with these issues,in this paper,we develop a novel evolutionary algorithm by modifying the original version of Whale Optimization Algorithm(WOA).To this end,a nonlinear function is introduced to improve the exploration and exploitation phases in the search process of ***,the modified WOA is applied to automatically obtain the initial values of weights and biases in FNN leading to reduce the probability of falling into local *** addition,the FNN model trained by the modified WOA is used to develop a classification approach for medical diagnosis *** medical diagnosis datasets are utilized to evaluate the efficiency of the proposed ***,four evaluation metrics including accuracy,AUC,specificity,and sensitivity are used in the experiments to compare the performance of classification *** experimental results demonstrate that the proposed method is better than other competing classification models due to achieving higher values of accuracy,AUC,specificity,and sensitivity metrics for the used datasets.

关键词： Feed forward neural network Meta-heuristic algorithm Whale optimization algorithm Optimization Classification Bionic algorithm

Past,present and future of indium phosphide quantum dots

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Nano Research 2022年第5期15卷 4468-4489页

作者： Houman Bahmani jalali Sadra Sadeghi Itir Bakis Dogru Yuksel Asim Onal Sedat Nizamoglu Graduate School of Biomedical Science and Engineering KoçUniversityIstanbul 34450Turkey Department of Electric and Electronics Engineering KoçUniversityIstanbul 34450Turkey Department of Material Science and Engineering KoçUniversityIstanbul 34450Turkey Present address:Photonic Nanomaterials Group Istituto Italiano di TecnologiaGenova 16124Italy Present address:Department of Electrical and Computer Engineering Queen's UniversityKingston K7L 3N6Canada Present address:Nanophotonics Group Debye Institute for Nanomaterials ScienceUtrecht UniversityUtrecht 3508 TAThe Netherlands

Indium phosphide(InP)colloidal quantum dots(QDs)have been drawn significant attention as a potentially less toxic alternative to cadmium-based QDs over the past two *** advances in their colloidal synthesis methods have allowed for the synthesis of a wide variety of compositions,heterojunctions,dopants,and ligands that enabled spectral tunability from blue to near-infrared,narrow emission linewidths,and perfect quantum yields approaching ***,it has higher covalency compared to cadmium chalcogenides leading to improved optical *** state-of-the-art InP QDs with appealing optical and electronic properties have excelled in many applications such as light-emitting diodes,luminescent solar concentrators(LSCs),and solar cells with high potential for *** review focuses on the history,recent development,and future aspect of synthesis and application of colloidal InP QDs.

关键词： indium phosphide InP quantum dot nanocrystal synthesis colloidal doping