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Multiple input self-organizing-map resNet model for optimization of petroleum refinery conversion units

Frontiers of Chemical Science and Engineering 2023年第6期17卷 759-771页

作者： Jiannan Zhu vladimir Mahalec Chen Fan Minglei Yang Feng Qian Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China Department of Chemical Engineering McMaster UniversityHamiltonOntario L8S 4L8Canada Engineering research Center of Process System Engineering Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

This work introduces a deep-learning network,i.e.,multi-input self-organizing-map resNet(MISr),for modeling refining units comprised of two reactors and a separation *** model is comprised of self-organizing-map and the neural network *** self-organizing-map part maps the input data into multiple two-dimensional planes and sends them to the neural network *** the neural network part,residual blocks enhance the convergence and accuracy,ensuring that the structure will not be overfitted *** of the MISr model of hydrocracking unit also benefits from the utilization of prior knowledge of the importance of the input variables for predicting properties of the *** results show that the proposed MISr structure predicts more accurately the product yields and properties than the previously introduced self-organizing-map convolutional neural network model,thus leading to more accurate optimization of the hydrocracker ***,the MISr model has smoother error convergence than the previous *** operating conditions have been determined via multi-round-particle-swarm and differential evolution *** experiments show that the MISr model is suitable for modeling nonlinear conversion units which are often encountered in refining and petrochemical plants.

关键词： hydrocracking convolutional neural networks self-organizing map deep learning data-driven optimization

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Scalable Deposition Methods for Large-Area Production of Perovskite Thin Films

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Energy & Environmental Materials 2019年第2期2卷 119-145页

作者： richard Swartwout Maximilian T.Hoerantner vladimir Bulovic Department of Electrical Engineering and Computer Science Massachusetts Institute of Technology77 Massachusetts AvenueCambridge MA 02139USA

The recent steady improvements in the performance of the nascent hybrid perovskite photovoltaic(PV)devices have led to power conversion efficiencies that rival the best-performing established PV ***,to scale these laboratory demonstrations to PV module-scale production will require development of scalable deposition methods for perovskite thin *** record result for perovskite PVs so far was achieved via spin coating,a technique that is popular in research laboratories for thin-film coating over relatively small device areas,but not considered to be a method that could be used to scale up the manufacturing of perovskite *** larger thin-film areas are needed for future commercial PV ***,some researchers have focused their efforts on perovskite deposition techniques that can be considered as scalable for mass production and have achieved notable results even on large ***,we present an overview of the solution-based and vapor-based deposition processes;we explain their influence on the molecular crystal growth behavior of perovskite thin films and discuss the morphology as well as other material quality *** presenting a comprehensive comparison of the deposition techniques and the corresponding performance parameters for different device sizes,we intent to guide the growing research community through the methods that might enable mass production of perovskite solar products.

关键词： perovskite solar cells scalable deposition solution processing vapor deposition

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relationship between mass discharge rate and granular temperature of silo flow with variance of outlets

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Particuology 2022年第4期20卷 76-82页

作者： Quan Chen ran Li Wengzheng Xiu vladimir Zivkovic Hui Yang School of Optical-Electrical and Computer Engineering University of Shanghai for Science and TechnologyShanghai 200093China School of Medical Instrument and Food Engineering University of Shanghai for Science and Technology Shanghai 200093China School of Engineering.Newcastle University NE17RUUnited Kingdom

A lower granular temperature zone near the orifice in silos was found by speckle visibility spectroscopy ***,the values of granular temperature in this area are inversely proportional to the mass discharge rate(MDr).This finding that links the macroscopic MDr with mesoscopic dynamics temperature of the particle system,is obtained by looking at the effect that different outlet sizes of silos on MDr and granular temperature *** from evidencing the relevance of a parameter that has been traditionally overlooked in silos,this relationship supposes a benchmark with which to explore the influence of small orifice sizes on *** these,we found that the frequency of intermittent clogging and their dependence on the size of the outlet.

关键词： Silos Granular flow Granular temperature Mass discharge rate

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Effectiveness of Bilateral Pulmonary Artery Banding in Patients with Hypoplastic Left Heart Syndrome and Congenital Heart Defects with a Functional Single Ventricle: A Single-Center retrospective Study

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Congenital Heart Disease 2022年第3期17卷 365-374页

作者： Vitaliy Suvorov vladimir Zaitcev Karolina Andrzejczyk Saint Petersburg State Pediatric Medical University Saint-PetersburgRussia Academisch Medisch Centrum Universiteit van Amsterdam AmsterdamNetherlands

Background:Bilateral banding of the branches of the pulmonary artery in patients with hypoplastic left heart syndrome(HLHS)and other duct dependent critical neonatal heart malformations can significantly reduce the incidence of severe complications in the postoperative period,especially in severely unstable *** our study we compared different surgical techniques of bilateral pulmonary artery banding(PAB)in respect to their success in balancing systemic and pulmonary blood ***:We included 44 neonates with a HLHS and congenital heart diseases(CHD)with a functional single ventricle underwent a hybrid operation:bilateral PAB and patent ductus arteriosus *** hybrid surgery for method No.1 is performed as a one-stage procedure,together with patent ductus arteriosus(PDA)*** median sternotomy,two Gore-Tex 1–2 mm wide bands with a diameter of 3–3.5 mm are *** we apply method No.2 then the thread is used to create *** No.3 is distinguished by intraoperative assessment of blood flow at the site of narrowing of the branches of the pulmonary artery and optional stenting of the *** cuff for banding is made of Gore-Tex *** when applying method Nos.1 and 2 is assessed by the change in invasive blood pressure and oxygen saturation after narrowing of the branches of the pulmonary ***,with these techniques PDA stenting by inserting the introducer via pulmonary artery trunk is ***:HLHS with mitral or aortic valve atresia or both was present in 19 patients(43.1%),with severe left heart obstruction resulting in PDA dependent systemic circulation in 16 babies(36.4%).CHD with single ventricle physiology occurred in 9 patients(20.5%).14 babies(31.8%)undergo the procedure following the method No.1,8 patients(18.2%)method No.2 and 22 patients(50%)method ***/Qs=1/1 was achieved in 30 patients(30/44,68.1%):as a result of the method No.1 was achieved in 5 patients(5/14,35.7%),method No.2 in 4 patien

关键词： Bilateral banding hybrid Norwood procedure pulmonary banding hybrid approach HLHS surgery single ventricle

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Transfer of motion through a microelectromechanical linkage at nanometer and microradian scales

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Microsystems & Nanoengineering 2016年第1期2卷 106-115页

作者： Craig r.Copeland Craig D.McGray Jon Geist vladimir A.Aksyuk Samuel M.Stavis Center for Nanoscale Science and Technology National Institute of Standards and TechnologyGaithersburgMD 20899USA Maryland Nanocenter University of MarylandCollege ParkMD 20742USA Engineering Physics Division National Institute of Standards and TechnologyGaithersburgMD 20899USA Modern Microsystems Silver SpringMD 20904USA

Mechanical linkages are fundamentally important for the transfer of motion through assemblies of parts to perform *** their behavior in macroscale systems is well understood,there are open questions regarding the performance and reliability of linkages with moving parts in contact within microscale *** challenges impede experimental studies to answer such *** this study,we develop a novel combination of optical microscopy methods that enable the first quantitative measurements at nanometer and microradian scales of the transfer of motion through a microelectromechanical *** track surface features and fluorescent nanoparticles as optical indicators of the motion of the underlying parts of the *** models allow precise characterization of the electrothermal actuation of the *** transfer of motion between translating and rotating links can be nearly ideal,depending on the operating *** coupling and decoupling of the links agree with an ideal kinematic model to within approximately 5%,and the rotational output is perfectly repeatable to within approximately 20 ***,stiction can result in nonideal kinematics,and input noise on the scale of a few millivolts produces an asymmetric interaction of electrical noise and mechanical play that results in the nondeterministic transfer of *** study establishes a new approach towards testing the performance and reliability of the transfer of motion through assemblies of microscale parts,opening the door to future studies of complex microsystems.

关键词： Electrothermal linkage microelectromechanical nanoparticle noise rotation tracking translation

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Deuterium retention in chemically vapor deposited tungsten carbide coatings and hot-rolled tungsten exposed to low-energy deuterium plasma

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Tungsten 2022年第1期4卷 10-19页

作者： vladimir Kh.Alimov Joachim roth Frumkin Institute of Physical Chemistry and Electrochemistry Russian Academy of SciencesMoscow 119071Russia Max-Planck-Institut fur Plasmaphysik 85748 GarchingGermany

Samples of chemically vapor deposited(CVD)coatings of tungsten carbides W_(45)C_(55)and W_(60)C_(40)and samples of hot-rolled tungsten were exposed to deuterium(D)plasma at sample temperatures ranging from 323 to 813 K,as a result of which the samples were irradiated with D ions with an energy of about 200 eV per D particle at a flux of D particles of about1.1×10^(21)D·m^(-2)·s^(-1)to a fluence of about 2×10^(24)D·m^(-2).The concentration of deuterium in these samples was examined by the D(3 He,p)4 He nuclear *** on the measured deuterium depth profiles and assuming that these profiles are determined by diffusing D atoms,the diffusion coefficients of deuterium in the CVD tungsten carbide coatings were *** these diffusion coefficients,an estimate of the Arrhenius relation for the diffusion coefficients of deuterium in CVD tungsten carbide coatings was obtained:D=2.5×10^(-3)exp(-1.12 eV/kT)m~2·s^(-1),where T is temperature expressed in Kelvin,and k is the Boltzmann *** concentration of trapped deuterium in the bulk of CVD tungsten carbide coatings is practically independent of the stoichiometry of the *** decreases from about 5×10^(-2)to about 7×10^(-4)D/(W+C)with an increase in the deuterium plasma exposure temperature from 373 to 813 *** concentration of trapped deuterium in hot-rolled tungsten,expressed in units of the D/W atomic ratio,is more than an order of magnitude lower than the concentration of deuterium in tungsten carbides,and also decreases with increasing plasma exposure temperature.

关键词： Chemically vapor deposited tungsten carbides Tungsten Deuterium plasma Deuterium depth profiles Deuterium diffusion coefficients

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A New Mantispid-Like Species of rhachiberothinae (Neuroptera:Berothidae) from Baltic Amber,with a Critical review of the Fossil record of the Subfamily

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Acta Geologica Sinica(English Edition) 2010年第4期84卷 655-664页

作者： vladimir N.MAKArKIN Janusz KUPrYJANOWICZ Institute of Biology and Soil Sciences Far Eastern Branch of the Russian Academy of SciencesVladivostokRussia Institute of Biology University of BialystokBialystokPoland Museum of the Earth the Polish Academy of SciencesWarsawPoland

Whalfera wiszniewskii sp. nov. is described from the Late Eocene Baltic amber. The genus Whalfera is considered as the only fossil genus confidently assigned to the rhachiberothinae. Others previously placed in this subfamily belong to Paraberothinae （except perhaps for Oisea）. The Late Eocene/present rhachiberothinae and the Cretaceous Paraberothinae are considered to be the subfamilies of Berothidae.

关键词： Neuroptera Berothidae rhachiberothinae Paraberothinae Mantispidae Symphrasinae

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Dynamics of Low-Viscosity Liquids Interface in an Unevenly rotating Vertical Layer

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Fluid Dynamics & Materials Processing 2024年第4期20卷 693-703页

作者： Victor Kozlov vladimir Saidakov Nikolai Kozlov Laboratory of Vibrational Hydromechanics Perm State Humanitarian Pedagogical UniversityPerm614990Russia Institut de Mécanique des Fluides de Toulouse Toulouse INPToulouse31400France

The behavior of two immiscible low-viscosity liquids differing in density and viscosity in a vertical flat layer undergoing modulated rotation is experimentally *** layer has a circular axisymmetric *** the absence of modulation of the rotation speed,the interphase boundary has the shape of a short axisymmetric cylinder.A new effect has been discovered,under the influence of rotation speed modulation,the interface takes on a new dynamic equilibrium state.A more viscous liquid covers the end boundaries of the layer in the form of thin films,which have the shape of round spots of almost constant radius;with increasing amplitude of the velocity modulation,the wetting boundary *** is found that upon reaching the critical amplitude of oscillations,the film of a viscous liquid loses stability,and the outer edge of the wetting spot collapses and takes on a feathery *** is shown that this threshold is caused by the development of the Kelvin-Helmholtz oscillatory instability of the *** spreading radius of a spot of light viscous liquid and its stability are studied depending on the rotation rate,amplitude,and frequency of rotation speed *** discovered averaged effects are determined by different oscillatory interaction of fluids with the end-walls of the cell,due to different *** effect of films forming can find application in technological processes to intensify mass transfer at interphase boundaries.

关键词： rotation oscillations immiscible fluids contact line interface film dynamic equilibrium Nomenclature frot

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Search for giant pulses of radio pulsars at frequency 111 MHz with LPA radio telescope

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research in Astronomy and Astrophysics 2018年第8期18卷 71-82页

作者： Andrey Nikolaevich Kazantsev vladimir Alexeevich Potapov E N.Lebedev Physical Institute of the russian Academy of Sciences Pushchino Radio Astronomy ObservatoryPushchino 142290Russia

We have used the unique low frequency sensitivity of the Large Phased Array （LPA） radio telescope of Pushchino radio Astronomy Observatory to collect a dataset consisting of single pulse observations of second period pulsars in the Northern Hemisphere. During observation sessions in 2011- 2017, we collected data on 71 pulsars at a frequency of 111 MHz using a digital pulsar receiver. We have discovered Giant radio Pulses （GrPs） from pulsars B0301＋09 and B 1237＋25, and confirmed earlier reported generation of anomalously strong （probable giant） pulses from B 1133＋16 in a statistically significant dataset. Data for these pulsars and from B0950＋08 and B 1112＋50, earlier reported as pulsars generating GrPs, were analyzed to evaluate their behavior over long time intervals. It was found that the statistical criterion （power-law spectrum of GrP distribution of energy and peak flux density） seems not to be strict for pulsars with a low magnetic field at their light cylinder. Moreover, spectra of some of these pulsars demonstrate unstable behavior with time and have a complex multicomponent shape. In the dataset for B0950＋08, we have detected the strongest GrP from a pulsar with a low magnetic field at its light cylinder ever reported, having a peak flux density as strong as 16.8 kJy.

关键词： stars neutron - pulsars general - pulsars individual (PSr B0301+19 PSr B0320+39 PSr B0329+54 PSr B0809+74 PSr B0950+08 PSr B1112+50 PSr B1133+16 PSr B1237+25) - pulsars giant pulses individual pulses

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Inversion of walkaway VSP data in the presence of lateral velocity heterogeneity

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Energy Geoscience 2024年第2期5卷 304-313页

作者： vladimir Grechka Ilya Tsvankin Pedro Contreras CWP Department of GeophysicsColorado School of MinesGoldenCO80401USA PDVSA-INTEVEP Apartado 76343Caracas1070AVenezuela Borehole Seismic LLC USA Department of Physics ULAVenezuela

Multi-azimuth walkaway vertical seismic profiling is an established technique for the estimation of in situ slowness surfaces and inferring anisotropy ***,this technique requires the assumption of lateral homogeneity,which makes the horizontal slowness components at depths of downhole receivers equal to those measured at the *** violations of this assumption,such as lateral heterogeneity or nonzero dip of intermediate interfaces,lead to distortions in reconstructed slowness surfaces and,consequently,to errors in estimated anisotropic *** this work,we relax the assumption of lateral homogeneity and discuss how to correct vertical seismic profile data for weak lateral *** describe a procedure of downward continuation of recorded traveltimes that accounts for the presence of both vertical inhomogeneity and weak lateral heterogeneity,which produces correct slowness surfaces at depths of downhole receivers,noticing that sufficiently dense receiver coverage along a borehole is required to separate influences of vertical and lateral heterogeneity on measured traveltimes and obtain accurate estimates of the slowness *** the slowness surfaces are found and a desired type of anisotropic model to be inverted is selected,the corresponding anisotropic parameters,providing the best fit to the estimated slownesses,can be *** invert the slowness surfaces of P-waves for parameters of the simplest anisotropic model describing dipping fractures(transversely isotropic medium with a tilted symmetry axis).Five parameters of this model,namely,the P-wave velocity V0 in the direction of the symmetry axis,Thomsen's anisotropic coefficients e and d,the tilt n,and the azimuth b of the symmetry axis,can be estimated in a stable manner when maximum source offset is greater than half of receiver depth.

关键词： Walkaway vertical seismic profile Lateral velocity heterogeneity Anisotropic parameter estimation Vertical inhomogeneity

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