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A Parametric Genetic Algorithm Approach to Assess Complementary Options of Large Scale Wind-solar Coupling

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IEEE/CAA Journal of Automatica Sinica 2017年第2期4卷 260-272页

作者： Tim Mareda Ludovic Gaudard franco Romerio Institute for Environmental Sciences University of Geneva Geneva School of Economics and Management(GSEM) University of Geneva

The transitional path towards a highly renewable power system based on wind and solar energy sources is investigated considering their intermittent and spatially distributed characteristics. Using an extensive weather-driven simulation of hourly power mismatches between generation and load, we explore the interplay between geographical resource complementarity and energy storage strategies. Solar and wind resources are considered at variable spatial scales across Europe and related to the Swiss load curve, which serve as a typical demand side reference. The optimal spatial distribution of renewable units is further assessed through a parameterized optimization method based on a genetic algorithm. It allows us to explore systematically the effective potential of combined integration strategies depending on the sizing of the system, with a focus on how overall performance is affected by the definition of network boundaries. Upper bounds on integration schemes are provided considering both renewable penetration and needed reserve power capacity. The quantitative trade-off between grid extension, storage and optimal wind-solar mix is *** paper also brings insights on how optimal geographical distribution of renewable units evolves as a function of renewable penetration and grid extent.

关键词： Energy optimization grid integration genetic algorithm optimal spatial distribution power system modeling

Non-isothermal Dissolution Modelling of Sigma Phase in Duplex Stainless Steels

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Acta Metallurgica Sinica(English Letters) 2016年第9期29卷 859-868页

作者： Paolo Ferro Alberto Fabrizi franco Bonollo Department of Management and Engineering University of PadovaStradella San Nicola 336100 VicenzaItaly

In this work, the non-isothermal dissolution kinetics of the sigma phase in duplex stainless steels has been studied and modelled. A semi-empirical model is proposed to describe the kinetics of sigma phase precipitation/dissolution during continuous heating starting from the isothermal transformation kinetics. The proposed model, which presumes validity of the additivity rule, is validated by means of experimental investigations. A good agreement is found between experimental and analytical results.

关键词： Kinetics Non-isothermal dissolution Modelling Semi-empirical models Sigma phase Duplex stainless steels

Effect of Bacillus amyloliquefaciens and Bacillus subtilis on fermentation, dynamics of bacterial community and their functional shifts of whole-plant corn silage

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Journal of Animal Science and Biotechnology 2022年第3期13卷 864-877页

作者： Jie Bai Marcia franco Zitong Ding Lin Hao Wencan Ke Musen Wang Dongmei Xie Ziqian Li Yixin Zhang Lin Ai Xusheng Guo State Key Laboratory of Grassland Agro-ecosystems School of Life SciencesCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhou 730000China Probiotics and Biological Feed Research Centre Lanzhou UniversityLanzhou 730000China Production systems Natural Resources Institute Finland(Luke)FI-31600 JokioinenFinland School of Food Science and Engineering Shanxi Agricultural UniversityTaigu 030801China China Animal Agriculture Association Beijing 100044China

Background:Bacillus amyloliquefaciens(BA)and Bacillus subtilis(BS)are usually used as feed supplements directly or bacterial inoculants in biological feeds for ***,few research have reported the effects of BA and BS on fermentation characteristics and bacterial community successions of whole-plant corn silage during *** the BA and BS inoculants have positive effects on silages,then they could not only improve fermentation characteristics,but also deliver BA or BS viable cells to ruminants,which would play its probiotic ***,the objectives of this study were to investigate the effects of BA and BS on the fermentation,chemical characteristics,bacterial community and their metabolic pathway of whole-plant corn ***:Freshly chopped whole-plant corn was inoculated without or with BA and BS,respectively,and ensiled for1,3,7,14 and 60 *** showed that BA and BS inoculations increased lactic acid concentrations of whole-plant corn silages compared with control,and BA inoculation decreased acetic acid concentrations,whereas BS inoculation decreased fiber contents and increased crude protein(CP)*** water-soluble carbohydrate contents and lower starch contents were observed in BA-and BS-inoculated silages compared with that in *** decreased CP content and increased non-protein nitrogen content were observed in BA-inoculated silage,which was consistent with the higher amino acid metabolism abundances observed in BA-inoculated *** addition,it was noteworthy that BA and BS inoculations increased the metabolism of cofactors and vitamins,and decreased the relative abundances of drug resistance:antimicrobial *** also found that the bacterial metabolism pathways were clearly separated into three clusters based on the ensiling times of whole-plant corn silage in the present *** were no significant differences in bacterial community compositions among the three groups during ***,BA and

关键词： Bacillus silage inoculants Function prediction Silage quality Zea mays

Stability of Nonlinear Differential-Algebraic Systems Via Additive Identity

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IEEE/CAA Journal of Automatica Sinica 2020年第4期7卷 929-941页

作者： Pierluigi Di franco Giordano Scarciotti Alessandro Astolfi the Electrical and Electronic Engineering Department Imperial College LondonLondon SW72AZUK

The stability analysis for nonlinear differentialalgebraic systems is addressed using tools from classical control theory. Sufficient stability conditions relying on matrix inequalities are established via Lyapunov Direct Method. In addition, a novel interpretation of differential-algebraic systems as feedback interconnection of a purely differential system and an algebraic system allows reducing the stability analysis to a smallgain-like condition. The study of stability properties for constrained mechanical systems, for a class of Lipschitz differential-algebraic systems and for an academic example is used to illustrate the theory.

关键词： Differential-algebraic systems Lyapunov method small-gain theorem stability analysis

Serendipity Virtual Elements for General Elliptic Equations in Three Dimensions

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Chinese Annals of Mathematics,Series B 2018年第2期39卷 315-334页

作者： lourenco beirAo da veiga franco brezzi franco dassi luisa donatella marini alessandro russo dipartimento di matematica e applicazioni università di milano-bicoccaVia Cozzi 53 I-20153 M i—lano Italy imati cnr Ferrata 1 I-27100 Pavia Italy dipartimento di matematica università di paviaVia Ferrata 5 I-27100 Pavia Italy

The authors study the use of the virtual element method(VEM for short) of order k for general second order elliptic problems with variable coefficients in three space dimensions. Moreover, they investigate numerically... 详细信息

关键词：椭圆形元素虚拟尺寸方程可变系数数字地学习

A two-stage process with temperature-shift for enhanced anthocyanin production in strawberry cell suspension cultures

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Science China Chemistry 1999年第4期42卷 345-350页

作者：张卫 Shintaro Furusaki Chris franco Department of Chemistry and Biotechnology Graduate School of Engineering The University of Tokyo 7-3-1 Hongo Bunkyo-ku Tokyo 113 Japan Biotechnology School of Medicine Flinders University of South Australia Bedford Park SA 5042 Australia

A two-stage process with temperature-shift has been developed to enhance the anthocyanin yield in suspension cultures of strawberry cells. The effect of the temperature-shift interval and the shift-time point was investigated for the optimization of this strategy. In this process, strawberry cells were grown at 30℃ （the optimum temperature for cell growth） for a certain period as the first stage, with the temperature shifted to a lower temperature for the second stage. In response to the temperature shift-down, anthoeyanin synthesis was stimulated and a higher content could be achieved than that at both boundary temperatures but cell growth was suppressed. When the lower boundary temperature was deereased, cell growth was lowered and a delayed, sustained maximum anthocyanin content was achieved. Anthocyanin synthesis was strongly influeneed by the shift-time point but cell growth was not. Consequently, the maximum anthocyanin content of 2.7 mg（?）g-fresh cell-1 was obtained on day 9 by a temperature-

关键词： strawberry cell suspension cultures anthocyanin temperature two-stage culture temperature-shift.

NPV risk simulation of an open pit gold mine project under the O'Hara cost model by using Gas

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International Journal of Mining Science and Technology 2017年第3期27卷 557-565页

作者： franco-Sepulveda Giovanni Campuzano Carlos Pineda Cindy Department of Materials and Minerals National University of Colombia Medellin 050036 Colombia

This paper analyzes an open pit gold mine project based on the O'Hara cost model. Hypothetical data is proposed based on different authors that have studied open pit gold projects, and variations are proposed according to the probability distributions associated to key variables affecting the NPV, like production level, ore grade, price of ore, and others, so as to see what if, in a gold open pit mine project of 3000 metric tons per day of ore. Two case scenarios were analyzed to simulate the NPV, one where there is low certainty data available, and the other where the information available is of high certainty. Results based on genetic algorithm metaheuristic simulations, which combine basically Montecarlo simulations provided by the Palisade Risk software, the O'Hara cost model, net smelter return and financial analysis tools offered by Excel are reported, in order to determine to which variables of the project is more sensitive the NPV.

关键词： Genetic algorithms(GAs) O’Hara cost model Montecarlo simulation Open pit gold mine NPV risk analysis

Extension of Noether's theorem in PT-symmetry systems and its experimental demonstration in an optical setup

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Science China(Physics,Mechanics & Astronomy) 2023年第4期66卷 13-27页

作者： Qi-Cheng Wu Jun-Long Zhao Yu-Liang Fang Yu Zhang Dong-Xu Chen Chui-Ping Yang franco Nori Quantum Information Research Center Shangrao Normal UniversityShangrao 334001China School of Physics Nanjing UniversityNanjing 210093China Department of Physics Hangzhou Normal UniversityHangzhou 311121China Theoretical Quantum Physics Laboratory RIKENWako-shiSaitama 351-0198Japan RIKEN Center for Quantum Computing RIKENWako-shiSaitama 351-0198Japan Physics Department The University of MichiganAnn Arbor 48109-1040USA

Noether’s theorem is one of the fundamental laws in physics,relating the symmetry of a physical system to its constant of motion and conservation *** the other hand,there exist a variety of non-Hermitian parity-time(PT)-symmetric systems,which exhibit novel quantum properties and have attracted increasing *** this work,we extend Noether’s theorem to a class of significant PT-symmetry systems for which the eigenvalues of the PT-symmetry Hamiltonian HPTchange from purely real numbers to purely imaginary numbers,and introduce a generalized expectation value of an operator based on biorthogonal quantum *** find that the generalized expectation value of a time-independent operator is a constant of motion when the operator presents a standard symmetry in the PT-symmetry unbroken regime,or a chiral symmetry in the PT-symmetry broken *** addition,we experimentally investigate the extended Noether’s theorem in PT-symmetry single-qubit and two-qubit systems using an optical *** experiment demonstrates the existence of the constant of motion and reveals how this constant of motion can be used to judge whether the PT-symmetry of a system is ***,a novel phenomenon of masking quantum information is first observed in a PT-symmetry two-qubit *** study not only contributes to full understanding of the relation between symmetry and conservation law in PT-symmetry physics,but also has potential applications in quantum information theory and quantum communication protocols.

关键词： Noether’s theorem PT-symmetry systems chiral symmetry optical setup

Simulation of a Shock Tube with a Small Exit Nozzle

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Journal of Thermal Science 2018年第1期27卷 34-38页

作者： Yigang Luan Matthias Olzmann franco Magagnato Harbin Engineering University HarbinChina Karlsruhe Institute of Technology(KIT) Institute of Physical ChemistryKaiserstrasse 1276131 KarlsruheGermany Karlsruhe Institute of Technology(KIT) Institute of Fluid MechanicsKaiserstrasse 1276131 KarlsruheGermany

Shock tubes are frequently used to rapidly heat up reaction mixtures to study chemical reaction mechanisms and kinetics in the field of combustion chemistry [1]. In the present work, the flow field inside a shock tube with a small nozzle in the end plate has been investigated to support the analysis of reacting chemical mixtures with an attached mass spectrometer and to clarify whether the usual assumptions for the flow field and the related thermodynamics are fulfilled. In the present work, the details of the flow physics inside the tube and the flow out of the nozzle in the end plate have been investigated. Due to the large differences in the typical length scales and the large pressure ratios of this special device, a very strong numerical stiffness prevails during the simulation process. Second-order ROE numerical schemes have been employed to simulate the flow field inside the shock tube. The simulations were performed with the commercial code ANSYS Fluent [2]. Axial-symmetric boundary conditions are employed to reduce the consumption of CPU time. A density-based transient scheme has been used and validated in terms of accuracy and efficiency. The simulation results for pressure and density are compared with analytical solutions. Numerical results show that a density-based numerical scheme performs better when dealing with shock-tube problems [5]. The flow field near the nozzle is studied in detail, and the effects of the nozzle to pressure and temperature variations inside the tube are investigated. The results show that this special shock-tube setup can be used to study high-temperature gas-phase chemical reactions with reasonable accuracy.

关键词：模拟过程试管出口基于密度反应机制燃烧化学反应混合物化学混合物