Bilevel optimal control of urban traffic-related air pollution by means of Stackelberg strategies

Air contamination and road congestion are two major problems in modern cities. Both are closely related and present the same source: traffic flow. To deal with these problems, governments impose traffic restrictions preventing the entry of vehicles into sensitive areas, with the final goal of decreasing pollution levels. Unfortunately, these restrictions force drivers to look for alternative routes that usually generate traffic congestions, resulting in longer travel times and higher levels of contamination. In this work, blending computational modelling and optimal control of partial differential equations, we formulate and analyse a bilevel optimal control problem with air pollution and drivers’ travel time as objectives and look for optimal solutions in the sense of Stackelberg. In this setting, the leader (local government) implements traffic restrictions meanwhile the follower (drivers set) acts choosing travel preferences against leader constraints. We discretize the problem and propose a numerical algorithm to solve it, combining genetic-elitist algorithms and interior-point methods. Finally, computational results for a realistic case posed in the Guadalajara Metropolitan Area (Mexico) are shown.Sistema Nacional de Investigadores | Ref. SNI-52768Programa para el Desarrollo Profesional Docente | Ref. PRODEP/103.5/16/8066Xunta de Galicia | Ref. ED431C 2018/50

Designing an ecologically optimized road corridor surrounding restricted urban areas: a mathematical methodology

The use of optimization techniques for the optimal design of roads and railways has increased in recent years. The environmental impact of a layout is usually given in terms of the land use where it runs (avoiding some ecologically protected areas), without taking into account air pollution (in these or other sensitive areas) due to vehicular traffic on the road. This work addresses this issue and proposes an automatic method for obtaining a specific corridor (optimal in terms of air pollution), where the economically optimized road must be designed in a later stage. Combining a 1D traffic simulation model with a 2D air pollution model, and using classical techniques for optimal control of partial differential equations, the problem is formulated and solved in the framework of Mixed Integer Nonlinear Programming. The usefulness of this approach is shown in a real case study posed in a region that suffers from serious episodes of environmental pollution, the Guadalajara Metropolitan Area (México)Xunta de Galicia | Ref. ED431C 2018/50Sistema Nacional de Investigadores | Ref. SNI-52768Programa para el Desarrollo Profesional Docente | Ref. PRODEP/103.5/16/806

The structure of the space of affine Kaehler curvature tensors as a complex module

We use results of Matzeu and Nikcevic to decompose the space of affine Kaehler curvature tensors as a direct sum of irreducible modules in the complex settin

Pot culture of Iris xiphium (Holland Iris) with different concentrations of earthworm humus and their lixiviates

Se evaluaron tres variedades de Iris xiphium L. cultivadas en maceta en cuatro proporciones de humus de lombriz y se aplicaron los lixiviados diluidos como bioabono foliar. El experimento se realizó en un diseño completamente al azar con arreglo trifactorial y se midieron ocho variables: longitud de tallo (LT), longitud de botón (LB), longitud de flor (LF), diámetro de botón (DB), diámetro de flor (DF), biomasa (B), área foliar (AF) y días de cosecha (DDC). Los resultados indicaron que la variedad Telstar resultó ser la más precoz. El mejor tratamiento en dicha variedad para las variables LT, LB, B, DF y DDC correspondió a la proporción 30/70 (% lombrihumus / % suelo) y la dilución 1:10 de lixiviado; el segundo mejor tratamiento fue en la variedad Discovery en la proporción 40/60 (%lombrihumus / %suelo) y dilución 1:10 de lixiviado para las variables LT, AF y B. El presente trabajo aporta nueva información en cuanto al uso de sustratos y abono foliar orgánicos para el manejo sustentable, con bajo impacto ambiental, en cultivos florícolas.Growth in pots of three varieties of Iris xiphium was evaluated in four proportions of earthworm humus and diluted lixiviate used as foliar organic fertilizer. The experiment was conducted in a completely randomized three factorial design where the following variables were measured: stem length (SL), bud length (BL), flower (FL), bud diameter (BD), flower diameter (FD), biomass (B), leaf area (LA) and days to harvest (HD). The results showed that the 'Telstar' range turned out to be the earlier. The best treatment in the range 'Telstar' for variables SL, BL, B, FD and HD corresponded to the proportion 30% of earthworm along with the 1:10 dilution of lixiviate the second best treatment was in the Discovery range with 40% of earthworm and 1:10 dilution of lixiviate for variables LT, AF and B. In regards the proportions of used earthworm the best results were obtained in the proportions 30 and 40% with the use of the 1:10 dilution lixiviate. The present study provides new information on the use of organic substrates and foliar fertilizer for sustainable, low environmental impact, flower crops.Fil: Milpa-Mejía, Silvia. Universidad Autónoma del Estado de México. Facultad de Ciencias AgrícolasFil: Grenón-Cascales, Graciela N.. Universidad Autónoma del Estado de México. Facultad de Ciencias AgrícolasFil: González-Castellanos, Anacleto. Universidad Autónoma del Estado de México. Facultad de Ciencias AgrícolasFil: Vázquez-García, Luis Miguel. Universidad Autónoma del Estado de México. Facultad de Ciencias Agrícola

Detecting Electronic States at Stacking Faults in Magnetic Thin Films by Tunneling Spectroscopy

Co islands grown on Cu(111) with a stacking fault at the interface present a conductance in the empty electronic states larger than the Co islands that follow the stacking sequence of the Cu substrate. Electrons can be more easily injected into these faulted interfaces, providing a way to enhance transmission in future spintronic devices. The electronic states associated to the stacking fault are visualized by tunneling spectroscopy and its origin is identified by band structure calculations.Comment: 4 pages, 4 figures; to be published in Phys. Rev. Lett (2000

EFFECT OF SEASON ON SERUM COPPER AND ZINC CONCENTRATIONS IN CROSSBRED GOATS HAVING DIFFERENT REPRODUCTIVE STATUS UNDER SEMIARID RANGELAND CONDITIONS IN SOUTHERN MEXICO STATE

The effect of season (rainy: RS, and dry: DS) and reproductive status on copper (Cu) and zinc (Zn) concentrations in blood serum of crossbred goats (BW= 36.01 ± 1.59 kg) were studied under semiarid rangeland conditions in Southern Mexico State. Blood samples from 80 crossbred goats were taken each season (RS and DS). The goats were clustered into 10 different groups considering their reproductive status. Concentrations of Cu and Zn in serum were assayed using atomic absorption. Data were analyzed using a general linear model procedure for a completely randomized design and differences among means were examined using a Tukey test. Blood serum concentrations of Cu and Zn were affected by reproductive status and season (P<0.001). In relation to the season, Cu and Zn serum levels were lower in RS than DS (P<0.05). Overall, kidded goats had the highest values (P<0.01) for Cu than other animals in both seasons (RS or DS). Anestrous goats had the lowest concentrations (P<0.01) for Zn during RS, while all goats at their second or more kidding, rearing single or twins, showed the highest concentrations of Zn (P<0.001) in this season. Adult goats in Southern Mexico State showed a deficiency of Cu and Zn, especially during RS. As such, mineral supplements should be provided with respect to these elements in feeding systems for goats under semiarid rangeland conditions in order to evaluate their impact on health and reproduction

Scanning tunneling microscopy of platinum electrode surfaces with different preferred crystallographic orientations

We have used scanning tunneling microscopy to study the surface microtopography of platinum electrodes preferentially oriented by a procedure denoted as electrochemical faceting. The treated specimens show clear reoriented patches on the surface in the form of steps with well-defined orientations separated by terraces of different sizes. The microscopic data obtained by STM correspond well with voltammetric analysis.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicada