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Petroleum 2023年第4期9卷 499-507页

作者： Ali Rahmani Mahsa Naderi ehsan hosseiny Petroleum Engineering Department Amirkabir University of Technology(Tehran Polytechnic)TehranIran Department of Mining&Metallurgical Engineering Yazd UniversityYazdIran

A significant phase of global warming appeared during the Llandovery and productive Silurian hot shale was preserved all over the *** lower Silurian shale is the main effective source rock for most of the Paleozoic hydrocarbon in Iran and the Arabian *** hot shales have become prospective resources for new energy such as shale *** regional distribution and shale gas potential of the lower Silurian hot shale in southern Iran and the Arabian plate are determined using outcrops and exploration well samples data from previous *** studied area has a high organic content(on average more than 2%),maximum burial depth is 5300 m,shale thickness of 30-200 m,organic matter maturities(most comparable),clay minerals content ranging from 20%to 57%,quartz content ranges from 20%to 49%,feldspar content ranges from 10%to 15%and calcite content ranges from 1.48%to 5%which all favor shale gas generation and *** concluded that southern Iran and east-central Saudi Arabia are two of the most sustainable and favorable locations for shale gas exploration and production for lower Silurian hot shale after assessing all of the key characteristics.

关键词： Silurian hot shale Shale gas Southern Iran Arabian plate Favorable shale gas areas

Quantization and Event-Triggered Policy Design for Encrypted Networked Control

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 946-955页

作者： Yongxia Shi ehsan Nekouei the Department of Electrical Engineering City University of Hong KongHong KongChina

This paper proposes a novel event-driven encrypted control framework for linear networked control systems(NCSs),which relies on two modified uniform quantization policies,the Paillier cryptosystem,and an event-triggered *** to the fact that only integers can work in the Pailler cryptosystem,both the real-valued control gain and system state need to be first quantized before *** is dramatically different from the existing quantized control methods,where only the quantization of a single value,e.g.,the control input or the system state,is *** handle this issue,static and dynamic quantization policies are presented,which achieve the desired integer conversions and guarantee asymptotic convergence of the quantized system state to the ***,the quantized system state is encrypted and sent to the controller when the triggering condition,specified by a state-based event-triggered strategy,is *** doing so,not only the security and confidentiality of data transmitted over the communication network are protected,but also the ciphertext expansion phenomenon can be ***,by tactfully designing the quantization sensitivities and triggering error,the proposed event-driven encrypted control framework ensures the asymptotic stability of the overall closedloop ***,a simulation example of the secure motion control for an inverted pendulum cart system is presented to evaluate the effectiveness of the theoretical results.

关键词： Cyber-security encrypted control event-triggered control(ETC) networked control systems(NCSs) semi-homomorphic encryption

Improving the Surface Roughness of Dental Implant Fixture by Considering the Size,Angle and Spraying Pressure of Sandblast Particles

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Journal of Bionic Engineering 2024年第1期21卷 303-324页

作者： ehsan Anbarzadeh Bijan Mohammadi School of Mechanical Engineering Iran University of Science and TechnologyTehranIran

In this study,different conditions of sandblasting on dental implant fixtures were investigated to achieve the best sandblasting conditions.18 different sandblasting conditions(Using 152 implant fixture samples)were examined,including parameters such as particle size,particle blasting pressure,and particle blasting *** surface treatment of the samples was performed using the SLA+Anodizing *** testing was performed for each of the 18 different states,and the average surface roughness of each of these was compared with each ***,a bone layer was placed on the sample with the closest average surface roughness to the standard and the least amount of aluminum oxide on its surface among the 18 different states,to confirm the accuracy and quality of the desired surface roughness by examining the bone formation process and *** results showed that state No.4(sandblast particle size:75µm,spraying pressure of sandblast particles:4 bar,sandblast particle spraying angle:30 degrees),which was prepared using the SLA+Anodizing method and had a surface roughness of 1.989µm(The percentage of Al_(2)O_(3)on the surface=6%),had the best sandblasting conditions and showed 95%cell viability and accelerated the treatment and bone formation process for about a *** simulation results,using Abaqus software,indicated that the stress distribution on the surface of the implant fixture in contact with the bone surface has increased by approximately 4.3%for state *** will help prevent loosening of the dental implant fixture over time.

关键词： Dental implants Surface treatment Sandblast Surface roughness Osseointegration

Bearing capacity of circular footings on multi-layered sand-waste tire shreds reinforced with geogrids

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第3期16卷 1085-1094页

作者： Mahmoud Ghazavi ehsan Khosroshahi Faculty of Civil Engineering K.N.Toosi University of TechnologyTehranIran

The presence of waste tires poses an environmental challenge as they occupy a significant amount of land and are expensive to dispose in ***,reusing waste tires can address this issue when waste tires are used in geotechnical *** determine the viability of this approach,laboratoryscale tests were conducted to investigate load-bearing capacity of circular footings on sand-tire shred(STS)mixtures with shredded waste tire contents of 5%e15%by weight and three different widths of *** investigation focused on analyzing the thickness of layers composed of STS mixtures,the soil cap,and the impact of geogrids on bearing *** results indicate that a specific mixture of sand and tire shreds provides the highest footing-bearing *** addition,the optimal shred content and size were found to be 10%by weight and 2 cm×10 cm,***,for a given tire shred width,a particular length provides the largest bearing *** results agree well with that of previous research conducted by the first author and his colleagues in direct shear and California bearing ratio(CBR)*** primary finding of this research is that the use of two-layered STS mixtures reinforced by geogrids significantly enhances the bearing capacity.

关键词： Geogrid Sand Waste tire shred Bearing capacity Waste tire shred optimization Tire shred aspect ratio

Safe Motion Planning and Control Framework for Automated Vehicles with Zonotopic TRMPC

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Engineering 2024年第2期33卷 146-159页

作者： Hao Zheng Yinong Li Ling Zheng ehsan Hashemi State Key Laboratory of Mechanical Transmissions College of Mechanical and Vehicle EngineeringChongqing UniversityChongqing 400044China Department of Mechanical Engineering University of AlbertaEdmontonAB T6G 2H5Canada

Model mismatches can cause multi-dimensional uncertainties for the receding horizon control strategies of automated vehicles(AVs).The uncertainties may lead to potentially hazardous behaviors when the AV tracks ideal trajectories that are individually optimized by the AV's planning *** address this issue,this study proposes a safe motion planning and control(SMPAC)framework for *** the control layer,a dynamic model including multi-dimensional uncertainties is established.A zonotopic tube-based robust model predictive control scheme is proposed to constrain the uncertain system in a bounded minimum robust positive invariant set.A flexible tube with varying cross-sections is constructed to reduce the controller *** the planning layer,a concept of safety sets,representing the geometric boundaries of the ego vehicle and obstacles under uncertainties,is *** safety sets provide the basis for the subsequent evaluation and ranking of the generated *** efficient collision avoidance algorithm decides the desired trajectory through the intersection detection of the safety sets between the ego vehicle and obstacles.A numerical simulation and hardware-in-the-loop experiment validate the effectiveness and real-time performance of the *** result of two driving scenarios indicates that the SMPAC can guarantee the safety of automated driving under multi-dimensional uncertainties.

关键词： Automated vehicles Automated driving Motion planning Motion control Tube MPC Zonotope

Hydrodynamic Assessment of A New Nature-Based Armour Unit on Rubble Mound Breakwater for Coastal Protection

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China Ocean Engineering 2024年第3期38卷 439-452页

作者： ehsan SAFA Alireza MOJTAHEDI Abdolmajid MOHAMMADIAN Mohamad Ali Lotfollahi YAGHIN Department of Water Resources Engineering Faculty of Civil EngineeringUniversity of TabrizTabriz ***Iran Faculty of Civil Engineering University of OttawaOttawa K1H 8M5Canada

This research proposes a novel nature-based design of a new concrete armour unit for the cover layer of a rubblemoundbreakwater. Armour units are versatile with respect to shape, orientation, surface condition details, and ***, a detailed analysis is required to investigate the exact state of their hydraulic interactions and structuralresponses. In this regard, the performance results of several traditional armour units, including the Antifer cube,Tetrapod, X-block and natural stone, are considered for the first step of this study. Then, the related observed resultsare compared with those obtained for a newly designed (artificial coral) armour unit. The research methodology utilizesthe common wave flume test procedure. Furthermore, several verified numerical models in OpenFOAM code areused to gain the extra required data. The proposed armour is configured to provide an effective shore protection as anenvironmental-friendly coastal structure. Thus it is designed with a main trunk including deep grooves to imitate thetypical geometry of a coral type configuration, so as to attain desirable performance. The observed results and ananalytic hierarchy process (AHP) concept are used to compare the hydraulic performance of the studied traditionaland newly proposed (artificial coral) armour units. The results indicate that the artificial coral armour unit demonstratesacceptable performance. The widely used traditional armour units might be replaced by newer designs for betterwave energy dissipation, and more importantly, for fewer adverse effects on the marine environment.

关键词： rubble mound breakwater hydraulic interaction armour unit analytic hierarchy process numerical model

Predictive active control of building structures using LQR and artificial intelligence

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 489-502页

作者： Nirmal S.Mehta Vishisht Bhaiya K.A.Patel ehsan Noroozinejad Farsangi Department of Civil Engineering SVNIT SuratGujarat 395007India Urban Transformations Research Centre Western Sydney UniversityNSWAustralia

This study presents a neural network-based model for predicting linear quadratic regulator(LQR)weighting matrices for achieving a target response *** on the expected weighting matrices,the LQR algorithm is used to determine the various responses of the *** responses are determined by numerically analyzing the governing equation of motion using the state-space *** training a neural network,four input parameters are considered:the time history of the ground motion,the percentage reduction in lateral displacement,lateral velocity,and lateral acceleration,Output parameters are LQR weighting *** study the effectiveness of an LQR-based neural network(LQRNN),the actual percentage reduction in the responses obtained from using LQRNN is compared with the target percentage ***,to investigate the efficacy of an active control system using LQRNN,the controlled responses of a system are compared to the corresponding uncontrolled *** trained neural network effectively predicts weighting parameters that can provide a percentage reduction in displacement,velocity,and acceleration close to the target percentage *** on the simulation study,it can be concluded that significant response reductions are observed in the active-controlled system using ***,the LQRNN algorithm can replace conventional LQR control with the use of an active control system.

关键词： active control system linear quadratic regulator artificial neural networks state-space approach response effectiveness factor resilience

Engineering Nano/Microscale Chiral Self‑Assembly in 3D Printed Constructs

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Nano-Micro Letters 2024年第3期16卷 313-332页

作者： Mohsen Esmaeili ehsan Akbari Kyle George Gelareh Rezvan Nader Taheri‑Qazvini Monirosadat Sadati Department of Chemical Engineering University of South CarolinaColumbiaSC 29208USA TA Instruments Waters LLCNew CastleDE 19720USA Biomedical Engineering Program University of South CarolinaColumbiaSC 29208USA

Helical hierarchy found in biomolecules like cellulose,chitin,and collagen underpins the remarkable mechanical strength and vibrant colors observed in living *** study advances the integration of helical/chiral assembly and 3D printing technology,providing precise spatial control over chiral nano/microstructures of rod-shaped colloidal nanoparticles in intricate *** designed reactive chiral inks based on cellulose nanocrystal(CNC)suspensions and acrylamide monomers,enabling the chiral assembly at nano/microscale,beyond the resolution seen in printed *** employed a range of complementary techniques including Orthogonal Superposition rheometry and in situ rheo-optic measurements under steady shear rate *** techniques help us to understand the nature of the nonlinear flow behavior of the chiral inks,and directly probe the flow-induced microstructural dynamics and phase transitions at constant shear rates,as well as their post-flow ***,we analyzed the photo-curing process to identify key parameters affecting gelation kinetics and structural integrity of the printed object within the supporting *** insights into the interplay between the chiral inks self-assembly dynamics,3D printing flow kinematics and photopolymerization kinetics provide a roadmap to direct the out-of-equilibrium arrangement of CNC particles in the 3D printed filaments,ranging from uniform nematic to 3D concentric chiral structures with controlled pitch length,as well as random orientation of chiral *** biomimetic approach can pave the way for the creation of materials with superior mechanical properties or programable photonic responses that arise from 3D nano/microstructure and can be translated into larger scale 3D printed designs.

关键词： Directed chiral self-assembly Cellulose nanocrystals Bioinspired nanocomposite 3D printing Rheology

Photo-thermal synergistic excitation:Feasible strategy to detect ethanol for wide bandgap ZIF-8at low work temperature

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Journal of Environmental Sciences 2024年第4期138卷 112-120页

作者： Shuhao Shi Qian Du Ming Hou Xiaolei Ye Li Yang Shenghui Guo Jianhong Yi Ullah ehsan Hongbo Zeng State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization Faculty of Metallurgical and Energy EngineeringKunming University of Science and TechnologyKunming 650093China Department of Chemical and Materials Engineering University of AlbertaEdmonton T6G 2V4Canada FEMTO-ST Institute(UMR CNRS 6174) Universite de Bourgogne Franche-Comte(UBFC)Universite de technologie de Belfort Montbéliard(UTBM)Site de MontbeliardBelfort F-90010France Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China

Zeolitic Imidazolate Framework-8(ZIF-8)material was prepared by chemical precipitation *** microstructure and physical properties of the as-prepared samples were characterized by XRD,BET,FESEM and UV *** self-made four-channel measurement device was used to test the gas sensitivity of ZIF-8 material toward ethanol gas under photo-thermal synergistic *** results showed that the sample was typical ZIF-8(E_(g)=4.96 eV)with a regular dodecahedron shape and the specific surface is up to 1793 m^(2)/*** as-prepared ZIF-8 has a gas response value of 55.04 to 100 ppm ethanol at 75℃ and it shows good gas sensing selectivity and repeated *** excellent gas sensitivity can be attributed to the increase of free electron concentration in the ZIF-8 conduction band by photo-thermal synergistic excitation,and the large specific surface area of ZIF-8 material provides more active sites for gas-solid surface *** reaction mechanism of ZIF-8 material under multi-field excitation was also discussed.

关键词： ZIF-8 material Photo-thermal synergistic excitation UV-light irradiation Photon-generated electron and hole Gas-sensitive property

Secrecy Outage Probability Minimization in Wireless-Powered Communications Using an Improved Biogeography-Based Optimization-Inspired Recurrent Neural Network

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Computers, Materials & Continua 2024年第3期78卷 3971-3991页

作者： Mohammad Mehdi Sharifi Nevisi Elnaz Bashir Diego Martín Seyedkian Rezvanjou Farzaneh Shoushtari ehsan Ghafourian Department of Industrial Engineering Iran University of Science and TechnologyNarmakTehran16846-13114Iran Department of Computer Science Iowa State UniversityAmesIowaIA50011USA ETSI de Telecomunicación Universidad Politécnica de MadridMadrid28040Spain Department of Engineering California State University East BayHaywardCalifornia94542USA Department of Industrial Engineering Bu-Ali Sina UniversityHamedan65178-38695Iran

This paper focuses on wireless-powered communication systems,which are increasingly relevant in the Internet of Things(IoT)due to their ability to extend the operational lifetime of devices with limited *** main contribution of the paper is a novel approach to minimize the secrecy outage probability(SOP)in these *** SOP is crucial for maintaining the confidentiality and integrity of data,especially in situations where the transmission of sensitive data is *** proposed method harnesses the power of an improved biogeography-based optimization(IBBO)to effectively train a recurrent neural network(RNN).The proposed IBBO introduces an innovative migration *** core advantage of IBBO lies in its adeptness at maintaining equilibrium between exploration and *** is accomplished by integrating tactics such as advancing towards a random habitat,adopting the crossover operator from genetic algorithms(GA),and utilizing the global best(Gbest)operator from particle swarm optimization(PSO)into the IBBO *** IBBO demonstrates its efficacy by enabling the RNN to optimize the system parameters,resulting in significant outage probability *** comprehensive simulations,we showcase the superiority of the IBBO-RNN over existing approaches,highlighting its capability to achieve remarkable gains in SOP *** paper compares nine methods for predicting outage probability in wireless-powered *** IBBO-RNN achieved the highest accuracy rate of 98.92%,showing a significant performance *** contrast,the standard RNN recorded lower accuracy rates of 91.27%.The IBBO-RNN maintains lower SOP values across the entire signal-to-noise ratio(SNR)spectrum tested,suggesting that the method is highly effective at optimizing system parameters for improved secrecy even at lower SNRs.

关键词： Wireless-powered communications secrecy outage probability improved biogeography-based optimization recurrent neural network