检索结果-南通市图书馆

An approach to net-centric control automation of technological processes within indust.ial IoT syst.ms

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Advances in Manufacturing 2017年第4期5卷 388-393页

作者： Nikita Voinov Igor Chernorutsky Pavel Drobintsev Vsevolod Kotlyarov institute of Computer science and technology Peter the Great St. Petersburg Polytechnic UniversityPolytechnicheskaya 29 Saint Petersburg Russia 195251

The use of indust.ial internet networks with net- centric control is the driving trend behind the future material manufacturing of goods and services. The promising future of this approach is provided by these complex net-centric syst.ms functioning with high relia- bility. The problem of intelligent net-centric control and reliable network functioning is fundamental, with the additional requirement that the syst.m should preserve st.keholder security and privacy according to policies. The issue is that such syst.ms are characterized by complex multi-parameter operability modes controlled by various criteria. This st.dy considers an approach to providing reliable management of complicated Internet of things （IoT） syst.ms. This is achieved by solving multi-criteria tasks over many processes of various physical natures. Corresponding methods of hierarchical decomposition of multi-criteria tasks, process levels of multi-criteria opti- mization, specifics of aggregation levels, and the mast.r equation of the optimization process are described.

关键词： Net-centric control Technological process Internet of things (IoT) Reliability Multi-criteria optimization

Modeling mechanical behaviors of composites with various ratios of matrixeinclusion properties using movable cellular automaton method

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence technology（防务技术） 2015年第1期11卷 18-34页

作者： A.Yu.SMOLIN E.V.SHILKO S.V.Ast.FUROV I.S.KONOVALENKO S.P.BUYAKOVA S.G.PSAKHIE institute of st.ength Physics and Materials science SB RAS Tomsk st.te University institute of High technology Physics Tomsk Polytechnic University skolkovo institute of science and technology

Two classes of composite materials are considered: classical metaleceramic composites with reinforcing hard inclusions as well as hard ceramics matrix with soft gel inclusions. Movable cellular automaton method is used for modeling the mechanical behaviors of such different heterogeneous materials. The method is based on particle approach and may be considered as a kind of discrete element method. The main feature of the method is the use of many-body forces of inter-element interaction within the formalism of simply deformable element approximation. It was shown that the st.ength of reinforcing particles and the width of particle-binder interphase boundaries had determining influence on the service characterist.cs of metaleceramic composite. In particular, the increasing of st.ength of carbide inclusions may lead to significant increase in the st.ength and ultimate st.ain of composite material. On the example of porous zirconia ceramics it was shown that the change in the mechanical properties of pore surface leads to the corresponding change in effective elast.c modulus and st.ength limit of the ceramic sample. The less is the pore size, the more is this effect. The increase in the elast.c properties of pore surface of ceramics may reduce its fracture energy.

关键词： Composites Metal ceramics Zirconia ceramics Gel Modeling Movable cellular automata Many-body interaction

Dist.ibuted Algorithm for Robust.Resource Allocation with Polyhedral Uncertain Allocation Parameters

在线全文

学校读者我要写书评

暂无评论

Journal of Syst.ms science & Complexity 2018年第1期31卷 103-119页

作者： ZENG Xianlin YI Peng HONG Yiguang School of Automation Beijing Institute of Technology Beijing 100081 China Department of Electrical and Syst.ms Engineering Washington University in St. Louis St. Louis MO 63130 USA Key Laboratory of Syst.ms and Control Institute of Systems Science Chinese Academy of Sciences Beijing 100190 China

This paper st.dies a dist.ibuted robust.resource allocation problem with nonsmooth objective functions under polyhedral uncertain allocation parameters. In the considered dist.ibuted robust.resource allocation problem, the（nonsmooth） objective function is a sum of local convex objective functions assigned to agents in a multi-agent network. Each agent has a private feasible set and decides a local variable, and all the local variables are coupled with a global affine inequality const.aint,which is subject to polyhedral uncertain parameters. With the duality theory of convex optimization,the authors derive a robust.counterpart of the robust.resource allocation problem. Based on the robust.counterpart, the authors propose a novel dist.ibuted continuous-time algorithm, in which each agent only knows its local objective function, local uncertainty parameter, local const.aint set, and its neighbors＇ information. Using the st.bility theory of differential inclusions, the authors show that the algorithm is able to find the optimal solution under some mild conditions. Finally, the authors give an example to illust.ate the efficacy of the proposed algorithm.

关键词： Dist.ibuted optimization resource allocation robust.optimization polyhedral uncertain parameters nonsmooth optimization

Cryst.l st.ucture prediction at finite temperatures

在线全文

学校读者我要写书评

暂无评论

npj Computational Materials 2023年第1期9卷 306-313页

作者： Ivan A.Kruglov Alexey V.Yanilkin Yana Propad Arslan B.Mazitov Pavel Rachitskii Artem R.Oganov Moscow institute of Physics and technology 9 Institutsky laneDolgoprudny 141700Russia Dukhov Research institute of Automatics(VNIIA) Moscow 127055Russia Emerging Technologies Research Center XPANCEODubai Investment Park FirstDubaiUnited Arab Emirates skolkovo institute of science and technology Skolkovo Innovation Center30-1 Bolshoy blvdMoscow 121205Russia.

Cryst.l st.ucture prediction is a central problem of cryst.llography and materials science, which until mid-2000s was consideredintractable. Several methods, based on either energy landscape exploration or, more commonly, global optimization, largely solvedthis problem and enabled fully non-empirical computational materials discovery. A major shortcoming is that, to avoid expensivecalculations of the entropy, cryst.l st.ucture prediction was done at zero Kelvin, reducing to the search for the global minimum ofthe enthalpy rather than the free energy. As a consequence, high-temperature phases (especially those which are not quenchableto zero temperature) could be missed. Here we develop an accurate and affordable solution, enabling cryst.l st.ucture prediction atfinite temperatures. st.ucture relaxation and fully anharmonic free energy calculations are done by molecular dynamics with aforcefield (which can be anything from a parametric forcefield for simpler cases to a trained on-the-fly machine learning interatomicpotential), the errors of which are corrected using thermodynamic perturbation theory to yield accurate results with full ab initioaccuracy. We illust.ate this method by applications to metals (probing the P–T phase diagram of Al and Fe), a refractory covalentsolid (WB), an Earth-forming silicate MgSiO_(3) (at pressures and temperatures of the Earth’s lower mantle), and ceramic oxide HfO_(2).

关键词： prediction st.ucture Cryst.l

Continuous dimethyl carbonate synthesis from CO_(2) and methanol over Bi_(x)Ce_(1-x)O_(δ) monoliths:Effect of bismuth doping on population of oxygen vacancies,activity,and reaction pathway

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Nano Research 2022年第2期15卷 1366-1374页

作者： Yongdong Chen Yue Li Wei Chen Wen Wu Xu Zhong-kang Han Ammara Waheed Zhongbin Ye Gao Li Alfons Baiker College of Chemist.y and Chemical Engineering Southwest Petroleum UniversityChengdu 610500China School of Physical science and technology Ningbo UniversityNingbo 315211China Center for Energy science and technology Skolkovo Institute of Science and TechnologySkolkovo Innovation CenterMoscow 143026Russia st.te Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China ETH Zurich Department of Chemistry and Applied BiosciencesInstitute for Chemical and BioengineeringHonggerbergHClCH-8093 ZurichSwitzerland

We evaluated bismuth doped cerium oxide catalyst. for the continuous synthesis of dimethyl carbonate(DMC)from methanol and carbon dioxide in the absence of a dehydrating ***_(x)Ce_(1-x)O_(δ)nanocomposites of various compositions(x=0.06-0.24)were coated on a ceramic honeycomb and their st.uctural and catalytic properties were *** incorporation of Bi species into the CeO_(2) lattice facilitated controlling of the surface population of oxygen vacancies,which is shown to play a crucial role in the mechanism of this reaction and is an important parameter for the design of ceria-based *** DMC production rate of the Bi_(x)Ce_(1-x)O_(δ) catalyst. was found to be st.ongly enhanced with increasing Ov *** concentration of oxygen vacancies exhibited a maximum for Bi_(0.12)Ce_(0.88)O_(δ),which afforded the highest.DMC production ***-term test. showed st.ble activity and selectivity of this catalyst.over 45 h on-st.eam at 140°C and a gas-hourly space velocity of 2,880 mL·g_(cat)^(-1)·h^(-1).In-situ modulation excitation diffuse reflection Fourier transform infrared spectroscopy and first.principle calculations indicate that the DMC synthesis occurs through reaction of a bidentate carbonate intermediate with the activated methoxy(-OCH_(3))*** activation of C0_(2) to form the bidentate carbonate intermediate on the oxygen vacancy sites is identified as highest.energy barrier in the reaction pathway and thus is likely the rate-determining st.p.

关键词： dimethyl carbonate synthesis bismuth-cerium oxides monolithic catalyst oxygen vacancies reaction mechanism

COPEX:co-evolutionary cryst.l st.ucture prediction algorithm for complex syst.ms

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

npj Computational Materials 2021年第1期7卷 1831-1841页

作者： Xiangyang Liu Haiyang Niu Artem R.Oganov st.te Key Laboratory of Solidification Processing International Center for Materials DiscoverySchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072P.R.China skolkovo institute of science and technology Skolkovo Innovation Center30 bldg.1 Bolshoy BoulevardMoscow 121205Russia

Cryst.l st.ucture prediction has been widely used to accelerate the discovery of new materials in recent *** to this day,it remains a challenge to predict the st.ble st.ichiometries and st.uctures of ternary or more complex syst.ms due to the explosive increase of the size of the chemical and configurational *** novel materials with a series of unique characterist.cs are expected to be found in this virgin territory while new algorithms to predict cryst.l st.uctures in complex syst.ms are urgently called *** by co-evolution in biology,here we propose a co-evolutionary algorithm,which we name COPEX,and which is based on the well-known evolutionary algorithm *** this proposed algorithm,a few USPEX calculations for ternary syst.ms and multiple for energetically-favored pseudobinary or fixed-composition syst.ms are carried out in parallel,and coevolution is achieved by sharing st.uctural information on the fittest.individuals among different USPEX sub-processes during the joint *** have applied the algorithm to W–Cr–B,Mg–Si–O,and Hf–Ta–C,three very different syst.ms,and many ternary compounds have been *** results clearly demonst.ate that the COPEX algorithm combines efficiency and reliability even for complex syst.ms.

关键词： algorithm evolutionary prediction

Exploring in-situ combust.on effects on reservoir properties of heavy oil carbonate reservoir

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum science 2024年第5期21卷 3363-3378页

作者： Aliya Mukhametdinova Tagir Karamov st.ahinja Markovic Andrey Morkovkin Aleksander Burukhin Evgeny Popov Zi-Qi Sun Ren-Bao Zhao Alexey Cheremisin skolkovo institute of science and technology(Skoltech) Sikorskogo 11Moscow121205Russia st.te Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Laboratory modeling of in-situ combust.on is crucial for underst.nding the potential success of field trials in thermal enhanced oil recovery(EOR) and is a vital precursor to scaling the technology for field applications. The high combust.on temperatures, reaching up to 480℃, induce significant petrophysical alterations of the rock, an often overlooked aspect in thermal EOR projects. Quantifying these changes is essential for potentially repurposing thermally treated, depleted reservoirs for CO_(2) *** this st.dy, we depart from conventional combust.on experiments that use crushed core, opting inst.ad to analyze the thermal effects on reservoir properties of carbonate rocks using consolidated samples. This technique maintains the intrinsic porosity and permeability, revealing combust.on's impact on porosity and mineralogical alterations, with a comparative analysis of these properties pre-and post.combust.on. We characterize porosity and pore geometry evolution using low-field nuclear magnetic resonance, X-ray micro-computed tomography, and low-temperature nitrogen adsorption. Mineral composition of the rock and grain-pore scale alterations are analyzed by scanning electron microscopy and X-ray *** analysis shows a significant increase in carbonate rocks' porosity, pore size and mineral alterations, and a transition from mixed-wet to a st.ongly water-wet st.te. Total porosity of rock samples increased in average for 15%-20%, and formation of new pores is regist.red at the scale of 1-30 μm ***-temperature exposure results in the calcite and dolomite decomposition, calcite dissolution and formation of new minerals—anhydrite and fluorite. Increased microporosity and the shift to st.ongly water-wet rock st.te improve the prospects for capillary and residual CO_(2) trapping with greater ***, these findings highlight the importance of laboratory in-situ combust.on modeling on consolidated rock over test. that use crushed core, an

关键词： In-situ combust.on Thermal EOR Carbonates Porosity and pore size MicroCT NMR SEM CO_(2)st.rage

Flexible surface-enhanced Raman scattering-active subst.ates based on nanofibrous membranes

在线全文

学校读者我要写书评

暂无评论

Nano Research 2018年第9期11卷 4468-4488页

作者： Ekaterina S. Prikhozhdenko Daniil N. Bratashov Dmitry A. Gorin Alexey M. Yashchenok Remote Controlled Theranost.c Syst.ms Lab Education and Research Institute of Nanostructures and Biosystems Saratov State University 83 As trakhanskaya Str. Saratov 410012 Russia Skoltech Center for Photonics and Quantum Materials Skolkovo Institute of Science and Technology Skolkovo Innovation Center 3 Nobel Str. Moscow 143026 Russia

Surface-enhanced Raman scattering （SERS） has emerged as an excellent analytical tool for the effective detection and fingerprint identification of various chemicals. Recently, significant progress has been made in the fabrication of SERS-active subst.ates using simple, inexpensive, and affordable methods. The full potential of universal SERS diagnost.cs will likely be realized with the development of approaches and devices capable of effectively detecting analytes on various surfaces as well as in multicomponent media. In addition, the combination of implantable or wearable SERS-active subst.ates and remote portable devices enables real-time diagnost.cs that ideally fit the concept of personalized medicine. In this paper, we summarize recent achievements in fabricating flexible SERS subst.ates made of cellulose paper, polymer membranes, and textile fibrous films. Emphasis is placed on the in-situ extraction and detection of various chemicals in real-world surfaces and complex media using flexible nanofibrous SERS platforms. The potential SERS applications and future perspectives in on-site diagnost.cs are also discussed.

关键词： paper electrospun membrane fabric surface-enhanced Ramanspectroscopy on-site diagnost.cs swabbing

Rheological st.dy of nanoparticle-based cationic surfactant solutions

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum 2022年第4期8卷 522-528页

作者： Ayomikun Bello Joy Ozoani Adewale Adebayo Dmitriy Kuriashov skolkovo institute of science and technology MoscowRussia Moscow Engineering Physics institute MoscowRussia Higher School of Economics MoscowRussia Kazan National Research Technological University KazanRussia

Worm-like micelles are of special interest.among the many forms of surfactant aggregates because of their usefulness in research and *** are elongated,flexible aggregates formed by amphiphilic molecules spontaneously self-organizing in *** nature of the surfactant determines its unique shape,which may be altered by mixing it with other subst.nces or changing physicochemical variables like as temperature,pH,or *** rheology of viscoelast.c fluid syst.ms is currently being modified using *** method,which was just.introduced about 10 years ago,has shown to be highly promising,producing significant improvements in rheological properties,particularly at reservoir *** goal of this research is to invest.gate and assess the rheology of an aqueous cationic surfactant solution based on graphene oxide *** thermodynamics,st.ucture and rheology of nanoparticle-based cationic surfactant solutions were invest.gated *** to st.uctural and thermodynamic invest.gations in surfactant-nanoparticle mixtures,micellenanoparticle interactions arise as physical crosslinks between *** exist.nce of these interactions is shown to generate considerable viscosity and viscoelast.city in wormlike micelles,even when the fluid is Newtonian in the absence of *** viscosity,shear modulus and relaxation time all increase as particle concentration *** nanoparticles generates a network of micellar entanglements as a result of *** results demonst.ate that adding nanoparticles to surfactant solutions provides for a one-of-a-kind method of altering fluid rheology under a range of circumst.nces.

关键词： Surfactant Wormlike micelles Nanoparticles Viscosity Modulus Rheology