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The Jacobian Dual of Certain mixed Product Ideals

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Algebra Colloquium 2020年第2期27卷 263-280页

作者： m.la Barbiera m.lahyane G.Restuccia Dipartimento di Scienze matematiche e Informatiche Scienze Fisiche e Scienze Della TerraUniversity of Messina98166 MessinaItaly Instituto de Fisica y matematicas(IFm)Universidad michoacana de San Nicolas de Hidalgo(UmSNH)Edificio C-3 Ciudad UniversitariaC.P.58040 MoreliaMichoacanMexico

We consider the symmetric algebra of a class of monomial ideals generated by *** these ideals with linear syzygies,we determine their Jacobian dual modules and study their duality properties.

关键词： graded algebra symmetric algebra monomial ideal Jacobian dual

一种应用于输电管理的动态安全控制新方法(英文)

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电力系统自动化 2004年第10期28卷 14-22页

作者： S.Bruno m.Dicorato m.la Scala 巴里大学电气与电子工程学系意大利巴里70125

提出了一种解决动态安全评估中的动态优化问题的方法。文中首先回顾了在连续时域空间的动态优化问题的描述方法,然后通过离散化,将该问题转换成离散时域空间的静态优化问题。解决该问题的方法可以用于评估保证系统动态和静态安全稳定的... 详细信息

提出了一种解决动态安全评估中的动态优化问题的方法。文中首先回顾了在连续时域空间的动态优化问题的描述方法,然后通过离散化,将该问题转换成离散时域空间的静态优化问题。解决该问题的方法可以用于评估保证系统动态和静态安全稳定的预防控制措施的效果。特别是,通过一个合同削减程序,可以评估在解除管制的市场环境下用于考虑安全约束的输电管理双边合同的修正电量。

关键词：动态优化动态安全评估预防控制合同削减双边合同输电管理

Concentrations and sources of an emerging pollutant, decabromodiphenylethane (DBDPE), in sewage sludge for land application

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Journal of Environmental Sciences 2012年第3期24卷 558-563页

作者： De la Torre A Concejero m A martínez m A Persistent Organic Pollutant Group Environment Department CIEMAT Avd. Complutense 22 Madrid 28040 Spain

The presence of an emerging brominated flame retardant, decabromodiphenylethane （DBDPE）, has been confirmed in Spanish sewage sludge. Thirty one samples from different urban wastewater treatment plants （WWTPs） were analyzed for this brominated flame retardant. DBDPE was positively identified and quantified in all samples at lower concentrations （47.0 ± 29.7 ng/g dry weight （dw）; mean ± SD） than those obtained for decabromodiphenyl ether （BDE-209）（290 ± 236 ng/g dw; mean ± SD） in a previous study. Influence of the WWTP characteristics in the pollutant levels was evaluated. No significant correlations were obtained between DBDPE concentrations and the population or sewage sludge production rate associated with the plants, neither wastewater treatment method. Sources of DBDPE in the sludge were also evaluated. Data indicate a common origin for DBDPE and BDE-209, which may be related to leaching processes during the use and disposal of consumer products containing these chemicals. Nevertheless, DBDPE contents are not influenced by industrial activities, which suggests that the infusion of DBDPE commercial mixture is not a source of this chemical into the environment, and indicates that the use of DBDPE in the Spanish industry is still low compared to deca-BDE.

关键词： decabromodiphenylethane polybrominated diphenyl ethers wastewater treatment plants sewage sludge

Stellar structure model in hydrostatic equilibrium in the context of f(R)-gravity

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Research in Astronomy and Astrophysics 2017年第12期17卷 31-40页

作者： Raíla Andr Gilberto m.Kremer Departamento de Fisica Universidade Federal do Parana81531-980 CuritibaBrazil manipal Centre for Natural Sciences Manipal UniversityManipal 576104India

In this work we present a stellar structure model from the f（R）-gravity point of view capable of describing some classes of stars（white dwarfs, brown dwarfs, neutron stars, red giants and the Sun）. This model is based on f（R）-gravity field equations for f（R） = R ＋ f2R2, hydrostatic equilibrium equation and a polytropic equation of state. We compare the results obtained with those found by Newtonian theory. It has been observed that in these systems, where high curvature regimes emerge,stellar structure equations undergo modifications. Despite the simplicity of this model, the results are satisfactory. The estimated values of pressure, density and temperature of the stars are within those determined by observations. This f（R）-gravity model has proved to be necessary to describe stars with strong fields such as white dwarfs, neutron stars and brown dwarfs, while stars with weaker fields, such as red giants and the Sun, are best described by Newtonian theory.

关键词： cosmology:theory stars:general massive brown dwarfs white dwarfs neutron

A Note on Tropical Triangles in the Plane

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Acta mathematica Sinica,English Series 2009年第11期25卷 1775-1786页

作者： m.ANSOla m.J.de la PUENTE Departamento de Algebra Facultad de matemáticas Universidad Complutense

We define transversal tropical triangles （affine and projective） and characterize them via six inequalities to be satisfied by the coordinates of the vertices. We prove that the vertices of a transversal tropical triangle are tropically independent and they tropically span a classical hexagon whose sides have slopes ∞, 0, 1. Using this classical hexagon, we determine a parameter space for transversal tropical triangles. The coordinates of the vertices of a transversal tropical triangle determine a tropically regular matrix. Triangulations of the tropical plane are obtained.

关键词： tropical triangles tropical triangulation linear inequalities convexity tropical semi-field

Numerical Analysis of a Combined Heat and Power Generation Technology from Residual Biomasses

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Journal of Energy and Power Engineering 2018年第6期12卷 300-321页

作者： C.Caputo D.Cirillo m.Costa m.la Villetta R.Tuccillo R.Villani Industrial Engineering Department University of Rome Tor VergataVia del Politecnico 100133 Rome-Italy CmD S.p.A. Research&Development DepartmentVia Pacinotti 281020 S.Nicola La Strada(CE)-Italy Istituto motori CNRViale Marconi 480125 Naples-Italy Department of Industrial Engineering University of Naples Federico IIVia Claudio 2180125 Naples-Italy

Energy valorization of organic waste material is nowadays an assessed practice of circular *** heat and power(CHP)technologies based on biomass gasification represent viable substitutes to traditional energy conversion units based on combustion,whose need has recently experienced a huge growth,due to the increasing concerns about the release of greenhouse gases(GHGs)emissions and the related effects on climate *** present,only a few solutions have yet achieved a level of full development for *** of them is the system developed by CmD,the CmD ECO20,made of a gasifier,a syngas cleaning system and a spark ignition internal combustion engine working as a *** the present work,a numerical model is developed to study this system into detail and search for optimal controlling *** sim.lation relies on a combined use of the Thermoflex?environment and a proper one-dimensional(1D)model of the engine module built within GT-Suite?.An original contribution is given to the turbulent combustion model that accounts for the laminar flame speed of the specific *** numerical model,that covers the entire biomass-to-energy conversion process,is validated under real operative *** final purpose of the work is the optimization of input parameters,as the initial biomass moisture content,the equivalence ratio at the gasifier or the timing of spark advance,to maximize the system electrical energy output.

关键词： Biomass CHP gasification internal combustion engine syngas wood chip

Generalized Graph Ideals of Linear Type

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Algebra Colloquium 2017年第1期24卷 83-91页

作者： m. la Barbiera P.L. Stagliano Department of mathematics University of MessinaViale Ferdinando Stagno d'A1contres 31 98166 Messina Italy

Let S = K[x1,..., xn; y1,..., ym] be the polynomial ring in two sets of variables over a field K. We investigate some classes of graph ideals of S, namely the generalized graph ideals, in order to classify ideals of l... 详细信息

关键词： ideals of mixed products graph ideals ideals of linear type

Observations of defect propagation in [100]-oriented opal-type photonic crystals

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Chinese Physics B 2008年第4期17卷 1298-1304页

作者：金崇君 Richard m.De la Rue Nigel P.Johnson Department of Electronics & Electrical Engineering University of Glasgow School of Physics and Engineering Laboratory of Optoelectronic Materials and TechnologiesSun Yat-Sen University

Charged colloidal suspensions have been used as experimental models for the study of crystal nucleation. Here we propose that the technique of tem.late-assisted colloidal self-assembly can be used to visualize the effects of defect propagation in atomic crystal films produced using epitaxial growth. Tem.lates with periodic line defects were used to grow [100]-oriented three-dimensional photonic crystals by means of the tem.late-assisted colloidal self-assembly method, aided by capillary and gravitational forces. The defect propagation in the [100]-oriented photonic crystal was observed using scanning electron microscopy, both at the surface of the crystal and on cleaved facets. This method is useful in the understanding of defect propagation in the growth of colloidal films on tem.lates - and the same approach may also prove useful for the understanding of atomic crystal growth on substrates with defects. Additionally, the deliberate incorporation of line defects may prove valuable as a way of introducing waveguide channels into three-dimensional photonic crystals.

关键词： photonic crystal colloidal crystal self-assembly

Cost of postoperative complications:How to avoid calculation errors

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World Journal of Gastroenterology 2020年第21期26卷 2682-2690页

作者： Roberto De la Plaza Llamas Josém Ramia Department of General and Digestive Surgery Hospital Universitario de GuadalajaraGuadalajara 19002Spain

Postoperative complications(PC)are a basic health outcome,but no surgery service in the world records and/or audits the PC associated with all the surgical procedures it *** studies that have assessed the cost of PC suffer from poor quality and a lack of transparency and *** payment system in place often rewards the volume of services provided rather than the quality of patients’clinical *** a thorough registration of PC,the economic costs involved cannot be *** accurate,reliable appraisal would help identify areas for investment in order to reduce the incidence of PC,improve surgical results,and bring down the economic *** article describes how to quantify and classify PC using the Clavien-Dindo classification and the comprehensive complication index,discusses the perspectives from which economic evaluations are performed and the minimum postoperative follow-up established,and makes various *** availability of accurate and impartially audited data on PC will help reduce their incidence and bring down ***,the health authorities,and society as a whole are sure to benefit.

关键词： morbidity Postoperative complications Costs and cost analysis Economic evaluation Healthcare costs Opportunity cost Clavien-Dindo classification Comprehensive complication index