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Nano-Micro Letters 2010年第4期2卷 227-234页

作者： Mojtaba Jamalizadeh Fazel sharifi Mohammad Hossein Moaiyeri Keivan Navi omid Hashemipour Department of Computer Engineering Science and Research Branch of Islamic Azad University Faculty of Electrical and Computer Engineering Shahid Beheshti University

Carbon Nano-Tube Field Effect Transistors(CNTFETs) are being widely studied as possible successors to silicon *** current mode has many advantages such as performing sum operation by means of a simple wired ***,direction of the current can be used to exhibit the sign of *** is expected that the advantages of current mode approaches will become even more important with increased speed requirements and decreased supply *** this paper,we present five new circuit designs for differential absolute value in current mode logic which have been simulated by CNTFET *** considered base current for this model is 2 μA and supply voltage is 0.9 *** all of our designs we used N-type CNTFET current mirrors which operate as truncated difference *** operation of Differential Absolute Value circuit calculates the difference between two input currents and our circuit designs are operate in 8 logic levels.

关键词： CNTFET Current mode Truncated difference Differential absolute value

The application of ResU-net and OBIA for landslide detection from multi-temporal Sentinel-2 images

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Big Earth Data 2023年第4期7卷 961-985页

作者： omid Ghorbanzadeh Khalil Gholamnia Pedram Ghamisi alnstitute of Advanced Research in Artificial Intelligence(IARAl) ViennaAustria Department of Remote Sensing and GIS University of TabrizTabrizIran Machine Learning Group Helmholtz-Zentrum Dresden-RossendorfHelmholtz Institute Freiberg for Resource TechnologyFreibergGermany

Landslide detection is a hot topic in the remote sensing community,particularly with the current rapid growth in volume(and variety)of Earth observation data and the substantial progress of computer *** learning algorithms,especially fully convolutional networks(FCNs),and variations like the ResU-Net have been used recently as rapid and automatic landslide detection *** FCNs have shown cutting-edge results in automatic landslide detection,accuracy can be improved by adding prior knowledge through possible *** study evaluates a rulebased object-based image analysis(OBIA)approach built on probabilities resulting from the ResU-Net model for landslide *** train the ResU-Net model using a landslide dataset comprising landslide inventories from various geographic regions,including our study area and test the testing area not used for *** the OBIA stage,we frst calculate land cover and image difference indices for pre-and post-landslide multi-temporal ***,we use the generated indices and the resulting ResU-Net probabilities for image segmentation;the extracted landslide object candidates are then optimized using rule-based *** the result validation section,the landslide detection of the proposed integration of the ResU-Net with a rule-based classification of OBIA is compared with that of the ResU-Net *** proposed approach improves the mean intersection-over-union of the resulting map from the ResU-Net by more than 22%.

关键词： Deep learning(DL) Eastern Iburi Japan European Space Agency(ESA) Fully Convolutional Networks(FCNs) object-based image analysis(OBIA) rapid landslide mapping ResUnet Sentinel-2

Moment tensor and stress inversion solutions of acoustic emissions during compression and tensile fracturing in crystalline rocks

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第10期15卷 2778-2786页

作者： Zihua Niu Bing Qiuyi Li omid Moradian Department of Earth Sciences Swiss Federal Institute of Technology(ETH)Zurich8006Switzerland Department of Civil and Environmental Engineering Western UniversityLondonONN6A 3K7Canada Department of Civil and Environmental Engineering Colorado School of MinesGoldenCO80401USA

We investigate the accuracy and robustness of moment tensor(MT)and stress inversion solutions derived from acoustic emissions(AEs)during the laboratory fracturing of prismatic Barre granite ***-cut flaws in the specimens introduce a complex stress field,resulting in a spatial and temporal variation of focal ***,we consider two experimental setups:(1)where the rock is loaded in compression to generate primarily shear-type fractures and(2)where the material is loaded in indirect tension to generate predominantly tensile-type *** each test,we first decompose AE moment tensors into double-couple(DC)and non-DC terms and then derive unambiguous normal and slip vectors using k-means clustering and an unstructured damped stress inversion *** explore temporal and spatial distributions of DC and non-DC events at different loading *** majority of the DC and the tensile non-DC events cluster around the pre-cut flaws,where macro-cracks later *** of stress inversion are verified against the stress field from finite element(FE)modeling.A good agreement is found between the experimentally derived and numerically simulated stress *** the best of the authors’knowledge,this work presents the first case where stress inversion methodologies are validated by numerical simulations at laboratory scale and under highly heterogeneous stress distributions.

关键词： Induced seismicity Acoustic emission(AE) Moment tensor(MT)inversion Stress inversion Finite element(FE)modeling

Development of Texture Mapping Approaches for Additively Manufacturable Surfaces

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 125-138页

作者： Bhupesh Verma omid Zarei Song Zhang Johannes Henrich Schleifenbaum Chair for Digital Additive Production RWTH Aachen University52074 AachenGermany

manufacturing(AM)technologies have been recognized for their capability to build complex components and hence have ofered more freedom to designers for a long *** ability to directly use a computer-aided design(CAD)model has allowed for fabricating and realizing complicated components,monolithic design,reducing the number of components in an assembly,decreasing time to market,and adding performance or comfort-enhancing *** of the features that can be introduced for boosting a component functionality using AM is the inclusion of surface texture on a given *** inclusion is usually a difcult task as creating a CAD model resolving fne details of a given texture is difcult even using commercial software *** paper develops a methodology to include texture directly on the CAD model of a target surface using a patch-based sampling texture synthesis algorithm,which can be manufactured using *** for the texture generation algorithm can be either a physical sample or an image with heightmap *** heightmap information from a physical sample can be obtained by 3D scanning the sample and using the information from the acquired point *** obtaining the required inputs,the patches are sampled for texture generation according to non-parametric estimation of the local conditional Markov random feld(MRF)density function,which helps avoid mismatched features across the patch *** generating the texture,a design constraint to ensure AM producibility is considered,which is essential when manufacturing a component using,e.g.,Fused Deposition Melting(FDM)or Laser Powder Bed Fusion(LPBF).The generated texture is then mapped onto the surface using the developed distance and angle preserving mapping *** implemented algorithms can be used to map the generated texture onto a mathematically defned *** paper maps the textures onto fat,curved,and sinusoidal surfaces for *** the texture m

关键词： Texture synthesis Design for additive manufacturing Image processing Textured surface generation Texture mapping

Postmiogypsinella intermedia Sirel and Gedik 2011 from the upper Oligocene of Central Iran(Qom Formation):Paleogeography and paleoenvironmental implications

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Journal of Palaeogeography 2023年第2期12卷 246-262页

作者： Mohsen Yazdi-Moghadam Mehdi Sarfi Mohammad sharifi Aliakbar Taghipour National Iranian Oil Company Exploration Directorate Sheikh Bahaie SquareTehran***Iran School of Earth Sciences Damghan UniversityDamghan***Iran Department of Earth Sciences Faculty of SciencesUniversity of KurdistanSanandajIran

Postmiogypsinella intermedia Sirel and Gedik,2011 is reported for the first time from the shallow-marine limestones of the upper Chattian Qom Formation,Central *** miogypsinid species has so far only been recorded from the upper Oligocene of Malatya(type locality)and Sivas(Central Anatolia)in eastern Turkey and from the upper Oligocene of the Prebetic Domain,SE *** new record from Central Iran,paleobiogeographically located at the Eurasian margin of the Tethyan Seaway between the Western and Eastern Tethys realms,indicates that the paleogeographic distribution of this species has to be extended eastwards as far as Central *** observation is not unexpected,since miogypsinid foraminifers with eccentric embryonic-nepionic apparatus(e.g.,Miogypsinella,Miogypsinoides,Miogypsina)are usually widely *** accompanying larger benthic foraminifera,including Miogypsinoides complanatus(Schlumberger),Miogypsinoides formosensis Yabe and Hanzawa,Spiroclypeus margaritatus(Schlumberger),Operculina complanata(Defrance),and Risananeiza pustulosa Boukhary et al.,indicate the late Chattian age(corresponding to SBZ 23 Biozone).Postmiogypsinella intermedia is indicative of a shallow-marine middle ramp environment with oligotrophic conditions and inhabited the relatively deeper part of the photic zone.

关键词： Larger foraminifera Miogypsinidae Biostratigraphy Qom Formation Central Iran

Evaluation of sour gas-low salinity waterflooding in carbonate reservoirs-A numerical simulation approach

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Petroleum Research 2023年第2期8卷 131-150页

作者： Lawrence Opoku Boampong Roozbeh Rafati Amin sharifi Haddad School of Engineering University of AberdeenFN371Fraser Noble BuildingSchool of EngineeringUniversity of AberdeenAB243UEUK

Although significant amount of H_(2)S(sour gas)rich natural gas is estimated globally,but not much attention has been given to the application of H_(2)S in the oil recovery *** studies on the use of H_(2)S in oil recovery processes showed that H_(2)S has the potential of improving the oil recovery,and it can be even more effective than using CO_(2) in some processes.H_(2)S can equally dissolve in the water,react with the reservoir rock to change its surface charge,porosity,and ***,previous in-vestigations on H_(2)S oil recovery attributed the improved oil recoveries to the higher miscibility of H_(2)S in the oil,and the reduction in the oil ***,there is limited understanding on the H_(2)S-oil-brine-rock geochemical interactions,and how they impact the oil recovery *** study aims to investigate the interactions between H_(2)S,oil,and carbonate formations,and to assess how the combi-nation of H_(2)S and low salinity water can impact the wettability and porosity of the reservoirs.A triple layer surface complexation model was used to understand the influence of key parameters(e.g.,pressure,brine salinity,and composition)on the H_(2)S-brine-oil-rock ***,the effects of mineral content of the carbonate rock on H_(2)S interactions were ***,the results of the H_(2)S-oil-brine-rock interactions were compared with a study where CO_(2) was used as the injected *** of the study showed that the seawater and its diluted forms yielded identicalζ-potential values of about 3.31 mV at a pH of *** indicates that at very low pH condition,pH controls the ζ-potential of the oil-brine interface regardless of the brine's ionic *** study further demonstrated that the presence of other minerals in the carbonate rock greatly reduced the calcite *** instance,the calcite dissolution was reduced by 4.5%when anhydrite mineral was present in the carbonate *** from the s

关键词： Low salinity water flooding Zeta potential Wettability alteration Carbonate reservoirs Carbon dioxide storage Sour gas injection

A hybrid framework to analyze crisis management system maturity in sociotechnical systems

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Journal of Safety Science and Resilience 2022年第4期3卷 302-320页

作者： Kamran Gholamizadeh Esmaeil Zarei Saman Poursiahbidi omid Kalatpour Center of Excellence for Occupational health and research Center of Health SciencesHamadan University of Medical SciencesHamadan ***Iran Centre for Risk Integrityand Safety Engineering(C-RISE)Faculty of Engineering and Applied ScienceMemorial University of NewfoundlandNL A1B 3X5Canada HSE Management Department Occupational Health and Safety Research CenterHamadan University of Medical SciencesHamadan ***Iran

In recent decades,numerous catastrophic accidents have occurred worldwide,ranging from natural events(such as tsunamis,flooding,and earthquakes)to industrial events(such as mining and chemical process disasters).They endanger humans,the environment,organizations,and societies,as well as national ***,there have been few attempts to propose a model for assessing the required capabilities and potential challenges in crisis management system maturity(CMSM).Accordingly,this study proposes a framework for measuring CMSM levels in complex *** this end,a CMSM taxonomy was developed,including aspects,dimensions,and factors influencing the *** inference sets and fuzzy analytical hierarchy processes are then used for knowledge acquisition,quantification of the CMSM,and dealing with epistemic *** actual complex petrochemical plant is investigated to evaluate its *** findings revealed the most significant con-tributing factors:the CMSM’s current capability and challenges level(score),as well as the capacity to overcome the potential crisis response ***,the proposed model can be used as a practical approach for various chemical-processing plants.

关键词： Crisis management system maturity Crisis capabilities Crisis challenges Chemical process industries Fuzzy sets theory

Carbon Isotope Stratigraphy of the Uppermost Aptian-Lower Cenomanian Strata from the Lut Block,East Iran

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Journal of Earth Science 2023年第6期34卷 1793-1799页

作者： Javad sharifi Seyed Naser Raisossadat Maryam Mortazavi Mehrizi Maryam Motamedalshariati Department of Geology Faculty of ScienceUniversity of BirjandBirjandIran Earth Sciences Research Group University of BirjandBirjandIran

The Mid-Cretaceous interval has been recognized as a crucial period in Earth’s history,and a number of studies on Neo-Tethyan successions illustrate intense evolutions in the nature of Mid-Cretaceous ocean chemistry,sea level,and marine faunal ***,much less investigations have been conducted in the Sistan Ocean,in the eastern ***,the Nimbolook Section(Lut Block,central Iran)has provided an opportunity to address these shortcomings and provide a better understanding of the paleoenvironmental changes in this *** biostratigraphic analysis and age interpretation of the Nimbolook Section have been performed in earlier investigations by means of planktonic foraminifera,ammonites and calcareous *** provides a reliable age framework for the chemostratigraphic *** the Nimbolook Section,the δ^(13)C stratigraphy was carried out on a total of 41 samples,which ranged between -3.26‰and 2.86‰ with an average of 1.09‰(standard deviation=1.15‰),and expanded within the upper Aptian to lower Cenomanian ***,there is a prominent negative shift at the base of the section,accompanied by episodes of sea-level ***,according to the age-diagnostic calcareous nannofossils records,this carbon isotope negative shift(0.88‰ to -3.26‰)straddle between late Aptian and early Albian ***,these new chemostratigraphic observations could be interpreted as being the coeval data from the reference well-studied successions in the other parts of the world,tentatively reflecting the oceanic anoxic event(OAE)1b.

关键词： Aptian-Albian Lut Block carbon isotope stratigraphy geochemistry Iran

Effect of synthetic fibers on resisting scour caused by horizontal jet

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Water Science and Engineering 2022年第2期15卷 152-160页

作者： Amin Ghassemi Mohsen Nasrabadi Mohammad Hossein omid Ali Raeesi Estabragh Department of Civil Engineering Queen's UniversityKingston K7L 3N6Canada Department of Water Science and Engineering Arak UniversityArak 38481-77584Iran Department of Irrigation and Reclamation Engineering University of TehranKaraj 31587-77871Iran

Given that the development of scour downstream of hydraulic structures increases the risk of structural damage,it is important to find cost-effective and environmental approaches to reduce this *** study aimed to experimentally evaluate the effect of synthetic fibers on the scour profile downstream of a sluice gate with a rigid *** were performed with the same Froude number and with different weight percentages of synthetic fibers on both non-cohesive and cohesive *** uniform sand was used as the non-cohesive sediment,and three different cohesive sediments were prepared by mixing different percentages of kaolinite soil with the used *** scouring experiments showed that the presence of synthetic fibers did not considerably affect the scour hole dimension in non-cohesive *** of the scour in the cohesive sediments in silty sand(SM)texture found that an increase in the percentage of silt reduced the scour hole *** effect of synthetic fibers on scour of SM-texture-based sediments was also investigated,and the results showed that increasing the percentage of synthetic fibers decreased the scour hole *** addition,the cohesive sediments in SM texture did not have a similar non-dimensional scour profile,and the presence of synthetic fibers did not significantly affect the scour hole.

关键词： Local scouring Synthetic fibers Horizontal jet SM soil texture Scour profile

NCFS:new chaotic fuzzy system as a general function approximator

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Journal of Control and Decision 2023年第4期10卷 514-528页

作者： Hamid Abbasi Mahdi Yaghoobi Arash sharifi Mohammad Teshnehlab Department of Computer Engineering Science and Research BranchIslamic Azad UniversityTehranIran Department of Electrical and Computer Engineering Mashhad BranchIslamic Azad UniversityMashhadIran Department of Electrical and Computer Engineering K.N.T University of TechnologyTehranIran

Conventional fuzzy systems(type-1 and type 2)are universal *** goal of this paper is to design and implement a new chaotic fuzzy system(NCFS)based on the Lee oscil-lator for function approximation and chaotic *** incorporates fuzzy reasoning of the fuzzy systems,self-adaptation of the neural networks,and chaotic signal generation in a unique *** features enable the structure to handle uncertainties by generating new information or by chaotic search among prior *** fusion of chaotic structure into the neurons of the membership layer of a conventional fuzzy system makes the NCFS more capable of confronting nonlinear *** on the GFA and Stone-Weierstrass theorems,we show that the proposed model has the function approximation *** NCFS perfor-mance is investigated by applying it to the problem of chaotic *** results are demonstrated to ilustrate the concept of function approximation.

关键词： Chaotic fuzzy system function approximation chaotic neural network oscillatory neuron