Sample records for degradar efluentes industriales

  1. Industrial Crafts. A Bilingual Text = Trabajos Manuales Industriales. Un Texto Bilingue.

    ERIC Educational Resources Information Center

    Los Angeles Unified School District, CA. Div. of Career and Continuing Education.

    This bilingual instructional text, one in a series of six texts covering various vocational and technical topics, provides secondary level English and Spanish instruction in industrial crafts. Addressed in the individual units are the following topics: plastics; laminating acrylic plastic; thermoforming plastics; sawing, shaping, and finishingÖ

  2. Industrial Crafts. A Bilingual Text = Trabajos Manuales Industriales. Un Texto Bilingue.

    ERIC Educational Resources Information Center

    Los Angeles Unified School District, CA. Div. of Career and Continuing Education.

    This bilingual instructional text, one in a series of six texts covering various vocational and technical topics, provides secondary level English and Spanish instruction in industrial crafts. Addressed in the individual units are the following topics: plastics; laminating acrylic plastic; thermoforming plastics; sawing, shaping, and finishing…

  3. Los plaguicidas y la contaminacion del medio ambiente Venezolano

    USGS Publications Warehouse

    Stickel, L.F.; Stickel, W.H.


    RESUMEN DE RECOMENDACIONES Recomendaciones para el Programa de Investigacion: 1. Establecer un sistema de muestreo biologico para detectar los niveles tendencias de los productos quimicos toxicos en un peque?o numero de si tios representativos. 2. Mantener continua vigilancia de la contaminacion ambiental, mediante la seleccion acertadamente dirigida de las zonas afectadas y de las fuentes de contaminacion. 3. Realizar estudios acerca de las poblaciones de animales silvestres, y del exito de los procesos reproductivos de las especies o grupos clayes de animales que se consideran mas gravemente afectados. 4. Preparar recomendaciones para una accion gubernamental de proteccion al hombre, a la fauna silvestre y al medio ambiente. Recomendaciones para la Accion Administrativa: 1. Establecer limites a la tolerancia de los residuos de plaguicidas en los alimentos. Constituye una medida clave para disminuir la contaminacion ambiental. 2. Establecer normas de calidad del agua para las corrientes, represas, la gos y otros cuerpos. Es la segunda medida clave para reducir la contaminacion del ambiente 3. Exigir un tratamiento adecuado de los efluentes industriales, especialmente antes de que se construyan las nuevas plantas. 4. Exigir a los agricultores que en el uso de plaguicidas sigan los consejos tecnicos autorizados y negar a los vendedores el derecho a recomendar productos por su cuenta. 5. Tomar medidas para recoger y eliminar los recipientes y sobrantes de los plaguicidas.

  4. Investigacion del sistema ABS/PC a partir de material reciclado procedente del sector electrico y electronico. Caracterizacion y optimizacion de mezclas industriales

    NASA Astrophysics Data System (ADS)

    Balart Gimeno, Rafael

    In the last years, polymer blends have acquired great relevance due to the excellent performances that can be reached. Particularly, ABS/PC blends show a growing interest since they exhibit good thermal and mechanical performance. All these features make them useful for technical applications: electronics, automotive, house ware and office,...PC contributes to a good thermal and mechanical stability, while ABS contributes, fundamentally, to the improvement of processability and cost reduction. Considering the importance of these blends, it has been developed the possibility to recycle ABS and PC by blending systems, following the residue generation ratio (around 4:1 for ABS:PC). In this research, we have worked with polycarbonate coming from city lighting and a most common degree of ABS. Due to the nature and origin of recycled materials, it is important to know and to quantify the previous level of degradation of individual materials as well as the thermal behaviour of the blends to establish the possible interaction of the components. We have used calorimetric and spectrophotometric techniques to identify previous degradation and the presence of impurities in the recycled as well as the characterization of the blends. Thermogravimetric analysis has been used for kinetic study of degradation processes and thermal stability of ABS/PC system. We have also studied mechanical properties of ABS/PC system due to the partial miscibility of the system which involves a reduction on mechanical performance, particularly plastic properties such as impact strength while resistant properties show no important decrease. The small decrease on impact strength can be attributed to the degradation processes of butadiene present in the ABS and interphase interaction between partial miscible phases. The addition of PC improves thermal stability of the blend since the thermal resistance of the PC is higher than that of ABS. Mechanical properties stand with good equilibrium and the processability of blends is quite good. All this features contributes to a high viability of the blending process of ABS/PC from recycled materials.


    EPA Science Inventory

    The U.S. Environmental Protection Agency issued e-fluent guidelines and limitations for the Metal Finishing Industry in June 1983. This report estimates the economic impact of pollution control costs in terms of price changes, effects profitability, potential plant closures, unem...

  6. Institutional Alternatives for High-Tech Training: The Case of ISVOR-FIAT. Training Discussion Paper No. 87.

    ERIC Educational Resources Information Center

    Araujo e Oliveira, Joao Batista

    ISVOR (Societa di Sviluppo e Addestramento Industriale) was incorporated in 1978 as an independent organization owned by Fiat to provide all training services. In 1988, in the area of technical training alone, ISVOR offered 534 different training programs to over 29,500 participants, in a total of approximately 348,000 man/days. FourÖ

  7. Experiences in Education Innovation: Developing Tools in Support of Active Learning

    ERIC Educational Resources Information Center

    Vera, Carlos; Felez, Jesus; Cobos, Jose Antonio; Sanchez-Naranjo, Maria Jesus; Pinto, Gabriel


    The paper focuses on educational projects developed in the ETSII (Escuela Tecnica Superior de Ingenieros Industriales) of the Polytechnic University of Madrid during the past few years. These projects were developed as new tools for enhancing the active role of students, for improving practical teaching, especially by means of virtual laboratories…

  8. "Bernardino Ramazzini, three hundred years after his death", Padua (Italy), October 18th, 2014.


    Riva, Michele Augusto; Zampieri, Fabio


    The year 2014 has marked the tercentenary from the death of Bernardino Ramazzini (1633-1714), universally credited as the founder of Occupational Health (5, 9, 10, 11). Indeed, the renowned physician died on November 5th 1714 in Padua, where he had been appointed as Professor of Practical Medicine at the local prestigious University from the year 1700. To commemorate this anniversary, the professors of Occupational Health of the University of Padua, the Italian Society of Occupational Health and Industrial Hygiene (Società Italiana di Medicina del Lavoro eIgiene Industriale, SIMLII), the International Commission on Occupational Health (ICOH) and the University of Padua organized a conference in the wonderful location of Palazzo Bo (Main Hall) under the patronage of the Padua Municipality, the Workers' Compensation Authority (INAIL), the Venetian Region and the Societas Internationalis Historiae Medicinae.[...]. PMID:25744315

  9. Vaporization inside a mini microfin tube: experimental results and modeling

    NASA Astrophysics Data System (ADS)

    Diani, A.; Rossetto, L.


    This paper proposes a comparison among the common R134a and the extremely low GWP refrigerant R1234yf during vaporization inside a mini microfin tube. This microfin tube has an internal diameter of 2.4 mm, it has 40 fins, with a fin height of 0.12 mm. Due to the high heat transfer coefficients shown by this tube, this technology can lead to a refrigerant charge reduction. Tests were run in the Heat Transfer in Micro Geometries Lab of the Dipartimento di Ingegneria Industriale of the Universit√† di Padova. Mass velocities range between 375 and 940 kg m-2 s-1, heat fluxes from 10 to 50 kW m-2, vapour qualities from 0.10 to 0.99, at a saturation temperature of 30¬įC. The comparison among the two fluids is proposed at the same operating conditions, in order to highlight the heat transfer and pressure drop differences among the two refrigerants. In addition, two correlations are proposed to estimate the heat transfer coefficient and frictional pressure drop during refrigerant flow boiling inside mini microfin tubes. These correlations well predict the experimental values, and thus they can be used as a useful tool to design evaporators based on these mini microfin tubes.

  10. Developing an ethical code for engineers: the discursive approach.


    Lozano, J Félix


    From the Hippocratic Oath on, deontological codes and other professional self-regulation mechanisms have been used to legitimize and identify professional groups. New technological challenges and, above all, changes in the socioeconomic environment require adaptable codes which can respond to new demands. We assume that ethical codes for professionals should not simply focus on regulative functions, but must also consider ideological and educative functions. Any adaptations should take into account both contents (values, norms and recommendations) and the drafting process itself. In this article we propose a process for developing a professional ethical code for an official professional association (Colegio Oficial de Ingenieros Industriales de Valencia (COIIV) starting from the philosophical assumptions of discursive ethics but adapting them to critical hermeneutics. Our proposal is based on the Integrity Approach rather than the Compliance Approach. A process aiming to achieve an effective ethical document that fulfils regulative and ideological functions requires a participative, dialogical and reflexive methodology. This process must respond to moral exigencies and demands for efficiency and professional effectiveness. In addition to the methodological proposal we present our experience of producing an ethical code for the industrial engineers' association in Valencia (Spain) where this methodology was applied, and we evaluate the detected problems and future potential. PMID:16609712

  11. Special Fluid Viscous Dampers For The Messina Strait Bridge

    SciTech Connect

    Colato, Gian Paolo; Infanti, Samuele; Castellano, Maria Gabriella


    The Messina Strait Bridge would be the world's longest suspension bridge, with a design earthquake characterised by a PGA value of 0.58 g and a distance between the ipocenter and the bridge of 15 km. Said critical structure of course would need a suitable restraint system for traffic braking loads, wind and seismic actions. Each type of load requires a specific behaviour of the restraint system, making its design a big challenge.The restraint system comprises special types of fluid viscous dampers, installed both in longitudinal and transverse direction, both at the towers and at the anchorages. In seismic conditions they behave as viscous dampers, to reduce the forces on the structural elements and the movements of the bridge deck. But in service dynamic conditions, e.g. under traffic or wind load, the devices shall behave like shock transmission units, thus preventing the longitudinal and transverse movements of the deck.FIP Industriale cooperated with the selected General Contractor, a consortium lead by Impregilo, in the design of said viscous dampers. This paper describes the main features of said devices.

  12. R1234yf vs. R134a Flow Boiling Heat Transfer Inside a 3.4 mm ID Microfin Tube

    NASA Astrophysics Data System (ADS)

    Diani, A.; Mancin, S.; Rossetto, L.


    The refrigerant charge minimization as well as the use of eco-friendly fluids can be considered two of the most important targets for these applications to cope with the new environmental challenges. This paper compares the R1234yf and R134a flow boiling heat transfer and pressure drop measurements inside a small microfin tube with internal diameter at the fin tip of 3.4 mm. This study is carried out in an experimental facility built at the Dipartimento di Ingegneria Industriale of the University of Padova especially designed to study both single and two phase heat transfer processes. The microfin tube is brazed inside a copper plate and electrically heated from the bottom. Several T -type thermocouples are inserted in the wall to measure the temperature distribution during the phase change process. In particular, the experimental measurements were carried out at constant saturation temperature of 30 ¬įC, by varying the refrigerant mass velocity between 190 kg m-2 s-1 and 940 kg m-2 s-1, the vapour quality from 0.2 to 0.99, at different imposed heat fluxes. The two refrigerants are compared considering the values of the two-phase heat transfer coefficient and pressure drop.

  13. SILER: Seismic-Initiated events risk mitigation in Lead-cooled Reactors

    SciTech Connect

    Forni, M.; De Grandis, S.


    SILER is a Collaborative Project, partially funded by the European Commission, aimed at studying the risk associated to seismic initiated events in Generation IV Heavy Liquid Metal reactors and developing adequate protection measures. The attention is focused on the evaluation of the effects of earthquakes (with particular regards to beyond design seismic events) and to the identification of mitigation strategies, acting both on structures and components design (as well as on the development of seismic isolation devices) which can also have positive effects on economics, leading to an high level of plant design standardization. Attention is also devoted to the identification of plant layout solutions able to avoid risks of radioactive release from both the core and other structures (i.e. the spent fuel storage pools). Specific effort is paid to the development of guidelines and design recommendations for addressing the seismic issue in next generation reactor systems. In addition, consideration will be devoted to transfer the knowledge developed in the project to Generation III advanced systems, in line with the objective of the SNE-TP SRA to support present and future Light Water Reactors and their further development, for which safety issues are key aspects to be addressed. Note, in this respect, that the benefits of base isolation in terms of response to design seismic actions are already widely recognized for Generation III LWRs, along with the possibility of a significant standardization of structural and equipment design. SILER activities started on October 1 st 2011 and are carried out by 18 partners: ENEA (Italy, Coordinator), AREVA NP SAS (France), SCK-CEN (Belgium), FIP Industriale (Italy), MAURER SOHENE (Germany), EC-JRC (Ispra (Italy)), SINTEC (Italy), KTH (Sweden), BOA-BKT (Germany), IDOM (Spain), ANSALDO (Italy), IPUL (Latvia), NUMERIA (Italy), VCE (Austria), SRS (Italy), CEA (France), EA (Spain), NUVIA (France). (authors)

  14. Beam-plasma dielectric tensor with Mathematica

    NASA Astrophysics Data System (ADS)

    Bret, A.


    We present a Mathematica notebook allowing for the symbolic calculation of the 3×3 dielectric tensor of an electron-beam plasma system in the fluid approximation. Calculation is detailed for a cold relativistic electron beam entering a cold magnetized plasma, and for arbitrarily oriented wave vectors. We show how one can elaborate on this example to account for temperatures, arbitrarily oriented magnetic field or a different kind of plasma. Program summaryTitle of program: Tensor Catalog identifier: ADYT_v1_0 Program summary URL: Program obtainable from: CPC Program Library, Queen's University of Belfast, N. Ireland Computer for which the program is designed and others on which it has been tested: Computers: Any computer running Mathematica 4.1. Tested on DELL Dimension 5100 and IBM ThinkPad T42. Installations: ETSI Industriales, Universidad Castilla la Mancha, Ciudad Real, Spain Operating system under which the program has been tested: Windows XP Pro Programming language used: Mathematica 4.1 Memory required to execute with typical data: 7.17 Mbytes No. of bytes in distributed program, including test data, etc.: 33 439 No. of lines in distributed program, including test data, etc.: 3169 Distribution format: tar.gz Nature of the physical problem: The dielectric tensor of a relativistic beam plasma system may be quite involved to calculate symbolically when considering a magnetized plasma, kinetic pressure, collisions between species, and so on. The present Mathematica notebook performs the symbolic computation in terms of some usual dimensionless variables. Method of solution: The linearized relativistic fluid equations are directly entered and solved by Mathematica to express the first-order expression of the current. This expression is then introduced into a combination of Faraday and Ampère-Maxwell's equations to give the dielectric tensor. Some additional manipulations are needed to express the result in terms of the dimensionless variables. Restrictions on the complexity of the problem: Temperature effects are limited to small, i.e. non-relativistic, temperatures. The kinetic counterpart of the present Mathematica will usually not compute the required integrals. Typical running time: About 1 minute on a Intel Centrino 1.5 GHz Laptop with 512 MB of RAM. Unusual features of the program: None.

  15. Distribution of a Community of Mammals in Relation to Roads and Other Human Disturbances in Gabon, Central Africa

    PubMed Central

    Vanthomme, Hadrien; Kolowski, Joseph; Korte, Lisa; Alonso, Alfonso


    Abstract We present the first community-level study of the associations of both roads and other human disturbances with the distribution of mammals in Gabon (central Africa). Our study site was in an oil concession within a littoral mosaic landscape. We conducted surveys along 199 line transects and installed camera traps on 99 of these transects to document mammal presence and abundance. We used generalized linear mixed-effect models to document associations between variables related to the ecosystem (land cover, topography, and hydrology), roads (coating, width of rights of way, condition, type of vehicle used on the road, traffic level, affiliation of users, and general type of road), and other human disturbances (urbanization, agriculture, hunting, logging, gathering, and industrial activities) and the abundance or presence of 17 species or groups of mammals including elephant (Loxodonta cyclotis), buffalo (Syncerus caffer), sitatunga (Tragelaphus spekei), red river hog (Potamochoerus porcus), smaller ungulates, gorilla (Gorilla gorilla), chimpanzee (Pan troglodytes), side-striped jackal (Canis adustus), carnivores, monkeys, and large rodents. Some types of roads and other human disturbances were negatively associated with the abundance or presence of elephants, buffalos, gorillas, sitatungas, some monkeys, and duikers. The pattern of associations of mammals with roads and other human disturbances was diverse and included positive associations with road presence (red river hog, some monkeys, and duikers), agriculture (sitatunga, small carnivores, and large rodents) and industrial activities (sitatunga, red river hog, red duikers, and side-striped jackal). Our results suggest that the community of mammals we studied was mostly affected by hunting, agriculture, and urbanization, which are facilitated by road presence. We recommend increased regulation of agriculture, hunting, and road building in the area. Distribuci√≥n de una Comunidad de Mam√≠feros en Relaci√≥n a Carreteras y Otras Perturbaciones Humanas en Gab√≥n, Africa Central Resumen Presentamos el primer estudio a nivel de comunidad de la relaci√≥n entre carreteras y otras perturbaciones humanas con la distribuci√≥n de mam√≠feros en Gab√≥n (√Āfrica central). Nuestro sitio de estudio est√° dentro de una concesi√≥n petrolera en un paisaje litoral heterog√©neo. Realizamos muestreos a lo largo de 199 transectos lineales e instalamos c√°maras trampa en 99 de ellos para documentar la presencia y abundancia de mam√≠feros. Utilizamos modelos lineales generalizados con efectos mixtos para documentar las asociaciones entre variables relacionadas con el ecosistema (cobertura de suelo, topograf√≠a e hidrolog√≠a), carreteras (tipo de revestimiento, ancho de derecho de v√≠a, condici√≥n, tipo de veh√≠culos que utilizan la carretera, nivel de tr√°fico, afiliaci√≥n de los usuarios y el tipo general de carretera) y otras perturbaciones humanas (urbanizaci√≥n, agricultura, caza, tala, recolecta y actividades industriales) y la abundancia o presencia de 17 especies o grupos de mam√≠feros incluyendo elefantes (Loxodonta cyclotis), b√ļfalo (Syncerus caffer), sitatunga (Tragelaphus spekei), cerdo rojo de r√≠o (Potomochoerus porcus), ungulados peque√Īos, gorila (Gorilla gorilla), chimpanc√© (Pan troglodytes), chacal con rayas a los lados (Canis adustus), carn√≠voros, monos y roedores de talla grande. Ciertos tipos de carreteras y otras perturbaciones humanas estuvieron asociadas negativamente con la abundancia o presencia de elefantes, b√ļfalos, gorilas, sitatungas, algunos monos y ant√≠lopes. Los patrones de asociaci√≥n de mam√≠feros con carreteras y otras perturbaciones humanas fueron diversos e incluyen asociaciones positivas con la presencia de carreteras (cerdo rojo de r√≠o, algunos monos y ant√≠lopes), agricultura (sitatunga, carn√≠voros peque√Īos y roedores de talla grande) y actividades industriales (sitatunga, cerdo rojo de r√≠o, ant√≠lope rojo y chacal con rayas a los lados). Nuestros resultados sugieren que la comunidad de mam√≠feros que estudiamos fue afectada principalmente por la caza, agricultura y urbanizaci√≥n, que son facilitadas por la presencia de carreteras. Recomendamos una mayor regulaci√≥n de la agricultura, caza y construcci√≥n de carreteras en el √°rea. PMID:23410077

  16. Downstream of downtown: urban wastewater as groundwater recharge

    NASA Astrophysics Data System (ADS)

    Foster, S. S. D.; Chilton, P. J.

    Wastewater infiltration is often a major component of overall recharge to aquifers around urban areas, especially in more arid climates. Despite this, such recharge still represents only an incidental (or even accidental) byproduct of various current practices of sewage effluent handling and wastewater reuse. This topic is reviewed through reference to certain areas of detailed field research, with pragmatic approaches being identified to reduce the groundwater pollution hazard of these practices whilst attempting to retain their groundwater resource benefit. Since urban sewage effluent is probably the only `natural resource' whose global availability is steadily increasing, the socioeconomic importance of this topic for rapidly developing urban centres in the more arid parts of Asia, Africa, Latin America and the Middle East will be apparent. L'infiltration des eaux us√©es est souvent la composante essentielle de toute la recharge des aquif√®res des zones urbaines, particuli√®rement sous les climats les plus arides. Malgr√© cela, une telle recharge ne constitue encore qu'un sous-produit incident, ou m√™me accidentel, de pratiques courantes vari√©es du traitement de rejets d'√©gouts et de r√©utilisation d'eaux us√©es. Ce sujet est pass√© en revue en se r√©f√©rant √† certaines r√©gions √©tudi√©es en d√©tail, par des approches pragmatiques reconnues pour permettre de r√©duire les risques de pollution des nappes dues √† ces pratiques tout en permettant d'en tirer profit pour leur ressource en eau souterraine. Puisque les effluents d'√©gouts urbains sont probablement la seule ¬ę ressource naturelle ¬Ľ dont la disponibilit√© globale va croissant constamment, l'importance socio-√©conomique de ce sujet est √©vidente pour les centres urbains √† d√©veloppement rapide de l'Asie, de l'Afrique, de l'Am√©rique latine et du Moyen-Orient. La infiltraci√≥n de aguas residuales es a menudo un componente principal de la recarga total en acu√≠feros ubicados en torno a zonas urbanas, especialmente en los climas m√°s √°ridos. A pesar de ello, dicho componente todav√≠a es una consecuencia secundaria (o incluso accidental) de diversas pr√°cticas asociadas con la manipulaci√≥n de las aguas residuales y con la reutilitzaci√≥n de aguas depuradas. Este tema se revisa mediante referencias a ciertas √°reas en las que existen investigaci√≥n detallada de campo, identificando enfoques pragm√°ticos con el fin de reducir el riesgo de contaminaci√≥n de las aguas subterr√°neas por tales pr√°cticas, a la vez tratando de conservar los beneficios para los recursos del acu√≠fero. Dado que los efluentes de aguas residuales urbanas son probablemente la √ļnica `fuente natural' cuya disponibilidad global se halla en del aumento, la importancia socioecon√≥mica de este tema ser√° evidente para los centros urbanos de r√°pido desarrollo en Asia, Latinoam√©rica y Oriente Medio.

  17. Managing for sustainability in an arid climate: lessons learned from 20 years of groundwater management in Arizona, USA

    NASA Astrophysics Data System (ADS)

    Jacobs, Katharine L.; Holway, James M.

    Substantial progress has been made within central Arizona in moving towards a more sustainable water future, particularly in transitioning the urban demand from a primarily nonrenewable groundwater-based supply to increasing dependence on the Colorado River, Salt River and effluent. Management efforts include a wide range of regulatory and voluntary programs which have had mixed success. The Department of Water Resources has learned a number of key lessons throughout the years, and this paper attempts to establish the water management context and identify those lessons for the benefit of others who may want to evaluate alternative approaches to groundwater management. Themes to be discussed include evaluating water management approaches in a public policy context, the effectiveness of alternative management approaches and the relative merits of regulatory vs. nonregulatory efforts, and the importance of high-quality data in making management decisions. De nets progr√®s ont √©t√© faits dans le centre de l'Arizona pour aller vers une gestion plus durable de l'eau, en particulier en reportant la demande urbaine d'une alimentation bas√©e sur l'eau souterraine primitivement non renouvelable sur une d√©pendance croissante des rivi√®res Colorado et Salt et des effluents. Les efforts de gestion portent sur une large gamme de programmes de r√©glementation et d'actions volontaires qui ont r√©ussi. Le D√©partement des Ressources en Eau a appris un certain nombre de le√ßons cl√©s au cours des ann√©es cet article tente d'√©tablir le contexte de gestion de l'eau et d'identifier ces le√ßons pour le b√©n√©fice de ceux qui cherchent √† √©valuer des approches alternatives de gestion de l'eau souterraine. Les th√®mes √† discuter portent sur l'√©valuation des approches de gestion de l'eau dans un contexte de politique publique, l'efficacit√© d'approches alternatives de gestion et les m√©rites relatifs d'efforts de r√©glementation par rapport √† une absence de r√©glementation, et l'importance de donn√©es de haute qualit√© dans la prise de d√©cisions de gestion. Resumen Se ha logrado un progreso substancial en el centro de Arizona para conseguir un futuro m√°s sustentable del agua, particularmente al trasladar la demanda urbana desde un suministro basado principalmente en aguas subterr√°neas no renovables hacia una mayor dependencia de las aguas superficiales de los r√≠os Colorado y Salado y de los efluentes de aguas depuradas. Los esfuerzos de gesti√≥n incluyen un amplio rango de programas legales y voluntarios que han tenido un √©xito combinado. El Departamento de Recursos H√≠dricos ha aprendido diversas lecciones clave a lo largo de los a√Īos, y este art√≠culo intenta establecer el contexto de la gesti√≥n del agua e identificar lo averiguado para beneficio de terceros que quieran evaluar enfoques alternativos para gestionar las aguas subterr√°neas. Entre los temas tratados, destaca la evaluaci√≥n de los enfoques de gesti√≥n del agua en un contexto pol√≠tico p√ļblico, la efectividad de enfoques alternativos de gesti√≥n y los m√©ritos relativos de los esfuerzos regulativos y no regulativos, y la importancia de los datos de alta calidad para la toma de decisiones de gesti√≥n. Groundwater use in many areas of Arizona greatly exceeds the natural replenishment of the aquifer, so although a portion of the groundwater use is renewable, the majority is not.

  18. PREFACE: DICE 2012 : Spacetime Matter Quantum Mechanics - from the Planck scale to emergent phenomena

    NASA Astrophysics Data System (ADS)

    Diósi, Lajos; Elze, Hans-Thomas; Fronzoni, Leone; Halliwell, Jonathan; Prati, Enrico; Vitiello, Giuseppe; Yearsley, James


    Presented in this volume are the Invited Lectures and the Contributed Papers of the Sixth International Workshop on Decoherence, Information, Complexity and Entropy - DICE 2012, held at Castello Pasquini, Castiglioncello (Tuscany), 17-21 September 2012. These proceedings may document to the interested public and to the wider scientific community the stimulating exchange of ideas at the meeting. The number of participants has been steadily growing over the years, reflecting an increasing attraction, if not need, of such conference. Our very intention has always been to bring together leading researchers, advanced students, and renowned scholars from various areas, in order to stimulate new ideas and their exchange across the borders of specialization. In this way, the series of meetings successfully continued from the beginning with DICE 20021, followed by DICE 20042, DICE 20063, DICE 20084, and DICE 20105, Most recently, DICE 2012 brought together more than 120 participants representing more than 30 countries worldwide. It has been a great honour and inspiration to have Professor Yakir Aharonov (Tel Aviv) with us, who presented the opening Keynote Lecture 'The two-vector quantum formalism'. With the overarching theme 'Spacetime - Matter - Quantum Mechanics - from the Planck scale to emergent phenomena', the conference took place in the very pleasant and inspiring atmosphere of Castello Pasquini - in beautiful surroundings, overlooking a piece of Tuscany's coast. The 5-day program covered these major topics: Quantum Mechanics, Foundations and Quantum-Classical Border Quantum-Classical Hybrids and Many-Body Systems Spectral Geometry, Path Integrals and Experiments Quantum -/- Gravity -/- Spacetime Quantum Mechanics on all Scales? A Roundtable Discussion under the theme 'Nuovi orizzonti nella ricerca scientifica. Ci troviamo di fronte ad una rivoluzione scientifica?' formed an integral part of the program. With participation of E Del Giudice (INFN & Università di Milano), F Guerra (Università 'La Sapienza', Roma) and G Vitiello (Università di Salerno), this event traditionally dedicated to the public drew a large audience involved in lively discussions until late. The workshop was organized by L Diósi (Budapest), H-T Elze (Pisa, chair), L Fronzoni (Pisa), J J Halliwell (London), E Prati (Milano) and G Vitiello (Salerno), with most essential help from our conference secretaries L Fratino, N Lampo, I Pozzana, and A Sonnellini, all students from Pisa, and from our former secretaries M Pesce-Rollins and L Baldini. Several institutions and sponsors supported the workshop and their representatives and, in particular, the citizens of Rosignano/Castiglioncello are deeply thanked for the generous help and kind hospitality: Comune di Rosignano - A Franchi (Sindaco di Rosignano), S Scarpellini (Segreteria sindaco), L Benini (Assessore ai lavori pubblici), M Pia (Assessore all' urbanistica) REA Rosignano Energia Ambiente s.p.a. - F Ghelardini (Presidente della REA), E Salvadori and C Peccianti (Segreteria) Associazione Armunia - A Nanni (Direttore), G Mannari (Programmazione), C Perna, F Bellini, M Nannerini, P Bruni and L Meucci (Tecnici). Special thanks go to G Mannari and her collaborators for advice and great help in all the practical matters that had to be dealt with, in order to run the meeting at Castello Pasquini smoothly Funds made available by Università di Pisa, Domus Galilaeana (Pisa), Centro Interdisciplinare per lo Studio dei Sistemi Complessi - CISSC (Pisa), Dipartimento di Ingegneria Industriale (Università di Salerno), Istituto Italiano per gli Studi Filosofici - IISF (Napoli), Solvay Italia SA (Rosignano), Institute of Physics Publishing - IOP (Bristol), Springer Verlag (Heidelberg), and Hungarian Scientific Research Fund OTKA are gratefully acknowledged. Last, but not least, special thanks are due to Laura Pesce (Vitrium Galleria, San Vincenzo) for the exposition of her artwork 'arte e scienza' at Castello Pasquini during the conference. The papers submitted in the wake of the conference have been edited by L Diósi, H-T Elze, L Fronzoni, J J Halliwell, E Prati, G Vitiello and J Yearsley. The proceedings follow essentially the order of presentation during the conference, separating, however, invited lectures and contributed papers6. In the name of all participants, we would like to thank S Toms with her collaborators at IOP Publishing (Bristol) for friendly advice and most valuable immediate help during the editing process and, especially, for their continuing efforts to make the Journal of Physics: Conference Series available to all. Budapest, Pisa, London, Milano, Salerno, Cambridge, April 2013 Lajos Diósi, Hans-Thomas Elze, Leone Fronzoni, Jonathan Halliwell, Enrico Prati, Giuseppe Vitiello and James Yearsley 1 Decoherence and Entropy in Complex Systems ed H-T Elze Lecture Notes in Physics 633 (Berlin: Springer, 2004) 2 Proceedings of the Second International Workshop on Decoherence, Information, Complexity and Entropy - DICE 2004 ed H-T Elze Braz. Journ. Phys. 35 A & 2B (2005) pp 205-529 free access at: 3 Proceedings of the Third International Workshop on Decoherence, Information, Complexity and Entropy - DICE 2006 eds H-T Elze, L Diósi and G Vitiello Journal of Physics: Conference Series 67 (2007); free access at: 4 Proceedings of the Fourth International Workshop on Decoherence, Information, Complexity and Entropy - DICE 2008> eds H-T Elze, L Diósi, L Fronzoni, J J Halliwell and G Vitiello Journal of Physics: Conference Series 174 (2009); free access at: 5 Proceedings of the Fifth International Workshop on Decoherence, Information, Complexity and Entropy - DICE 2010 eds H-T Elze, L Diósi, L Fronzoni, J J Halliwell, E Prati, G Vitiello and J Yearsley Journal of Physics: Conference Series 306 (2011); free access at: 6 We regret that invited lectures by Y Aharonov, J Barbour, G Casati and X-G Wen could not be reproduced here, partly for copyright reasons

  19. Urbanization and the groundwater budget, metropolitan Seoul area, Korea

    NASA Astrophysics Data System (ADS)

    Kim, Yoon-Young; Lee, Kang-Kun; Sung, Ig Hwan


    The city of Seoul is home to more than 10 million people in an area of 605 km2. Groundwater is ed for public water supply and industrial use, and to drain underground facilities and construction sites. Though most tap water is supplied from the Han River, the quantity and quality of groundwater is of great concern to Seoul's citizens, because the use of groundwater for drinking water is continuously increasing. This study identifies the major factors affecting the urban water budget and quality of groundwater in the Seoul area and estimates the urban water budget. These factors include leakage from the municipal water-supply system and sewer systems, precipitation infiltration, water-level fluctuations of the Han River, the subway pumping system, and domestic pumping. The balance between groundwater recharge and discharge is near equilibrium. However, the quality of groundwater and ability to control contaminant fluxes are impeded by sewage infiltration, abandoned landfills, waste dumps, and abandoned wells. R√©sum√©. La ville de S√©oul poss√®de une population de plus de 10 millions d'habitants, pour une superficie de 605 km2. Les eaux souterraines sont pomp√©es pour l'eau potable et pour les usages industriels, ainsi que pour drainer les √©quipements souterrains et les sites en construction. Bien que l'essentiel de l'eau potable provienne de la rivi√®re Han, la quantit√© et la qualit√© de l'eau souterraine pr√©sentent un grand int√©r√™t pour les habitants de S√©oul, parce qu'on utilise de plus en plus l'eau souterraine pour l'eau potable. Cette √©tude identifie les facteurs principaux qui affectent la qualit√© de l'eau souterraine dans la r√©gion de S√©oul et fait l'estimation du bilan d'eau urbaine. Les principaux facteurs affectant le bilan d'eau urbaine et la qualit√© de l'eau souterraine sont les fuites du r√©seau d'adduction et du r√©seau d'√©gouts, l'infiltration des eaux de pr√©cipitation, les fluctuations du niveau de la rivi√®re Han, le r√©seau de pompage du m√©tro et les pompages priv√©s. Le bilan entre la recharge de la nappe et sa d√©charge est proche de l'√©quilibre. Cependant, les infiltrations d'eaux us√©es, les d√©charges abandonn√©es, les d√©charges d'ordures et les puits abandonn√©s portent atteinte √† la qualit√© de l'eau souterraine et √† la capacit√© de contr√īler les flux de contaminants. Resumen. La ciudad de Se√ļl tiene m√°s de 10 millones de habitantes en un √°rea de 605 km2. Se bombea aguas subterr√°neas para abastecimiento urbano y para usos industriales, as√≠ como para el drenaje de instalaciones subterr√°neas y de solares en construcci√≥n. Aunque la mayor parte del agua de boca procede del r√≠o Han, los ciudadanos de Se√ļl est√°n muy concienciados por la cantidad y calidad de las aguas subterr√°neas, ya que su explotaci√≥n para uso de boca est√° experimentando un continuo incremento. El presente estudio identifica los factores que m√°s afectan a la calidad de las aguas subterr√°neas en el √°rea de Se√ļl y hace una estimaci√≥n del balance de agua en el territorio urbano. Entre los factores principales que afectan al balance y a la calidad de las aguas subterr√°neas, se incluye el lixiviado de la red municipal de suministro y de la red de alcantarillado, la infiltraci√≥n de agua de lluvia, las fluctuaciones del nivel del r√≠o Han, el sistema de bombeo del metro y los bombeos dom√©sticos. El balance entre la recarga y la descarga en el acu√≠fero est√° pr√≥ximo al equilibrio. Sin embargo, la calidad de las aguas subterr√°neas y la capacidad de controlar los flujos de contaminaci√≥n est√°n amenazadas por la infiltraci√≥n de aguas residuales, vertederos abandonados, dep√≥sitos de residuos y pozos abanadonados.

  20. Estudio de la influencia de la refrigeracion con aire de forma natural e inducida en el comportamiento de instalaciones fotovoltaicas

    NASA Astrophysics Data System (ADS)

    Mazon Hernandez, Rocio

    The aim is to analyse the negative influence of high panel temperatures on electrical production when they are placed on steel roofs of industrial buildings and greenhouse roofs. Different configurations have been tested in order to allow cooling of photovoltaic panels to decrease panel temperature and improve electrical performance. To research this problem two experimental facilities have been built. The first facility includes two panels fixed on a structure. A panel is integrated on a parallel steel plate which does not allow sufficient cooling. Between both surfaces, there is an open air channel in which an air flow is created by the chimney effect thus cooling the panel by natural convection or inducing air, using a fan, by forced convection. The other panel has not any plate underneath it and is used as a referent. The electrical behaviour of the integrated panel has been studied for different air gaps and induced velocities, being also compared with the reference panel. An experimental model was developed to establish correlations which allow determine the panel temperature depending on the influential variables on the cooling ability. This research also analyses the data of a working solar plant, with the same panel model, obtaining the correlations between electrical variables and panel temperature. A comparison with the electrical behaviour in the experimental facility and the solar plant is also presented. The second experimental facility is a replica of a photovoltaic greenhouse. It consists of four photovoltaic panels placed on the plastic roof, providing an open and divergent channel between both surfaces thus creating an air flow by natural convection. This research studies the effect of high temperatures within the greenhouse which is transferred by the roof and thus affects the electrical production. In addition, two air gaps were used and the effect of adding insulating material to the plastic roof was studied. The electrical variables of the panels are analysed to compare and select the best configuration. The presented research provides a deep knowledge of how they work as well as information and results for an improvement in future designs of building integrated photovoltaic systems. Este estudio se centra en analizar la influencia negativa de la temperatura en la produccion electrica de paneles fotovoltaicos al estar emplazados sobre cubierta de acero, como sucede en naves industriales y sobre un invernadero. Se estudian diferentes configuraciones que permitan refrigerar los paneles, reduciendo su temperatura y mejorar su rendimiento. Para abordar este problema, se han construido dos instalaciones experimentales, fieles a plantas solares en funcionamiento. Una instalacion engloba dos paneles fotovoltaicos sobre estructura fija al suelo. Uno de los paneles esta integrado sobre una superficie paralela y metalica. Entre ambas superficies existe un espacio que posibilita circular aire, permitiendo refrigerar el panel por conveccion natural, o conveccion forzada impulsando el aire con un ventilador. El otro panel, libre por su cara posterior y se ha considerado de referencia. Se ha estudiado el comportamiento del panel integrado sobre cubierta para diferentes secciones de aire y velocidades inducidas, comparandolo con el panel de referencia. Se ha desarrollado un modelo experimental que nos permite determinar la temperatura del panel en funcion de las variables que influyen en su refrigeracion. Adicionalmente, se han analizado los datos de una planta solar en funcionamiento, con paneles de igual caracteristicas, obteniendo correlaciones entre la temperatura del panel y las variables electricas y comparandolos con las obtenidas en la instalacion experimental. La segunda instalacion experimental reproduce parte de una instalacion solar sobre un invernadero, formada por cuatro paneles fotovoltaicos colocados sobre el plastico del invernadero, existiendo un canal divergente entre ambas superficies. Se estudia la influencia de las altas temperaturas en el interior del invernadero sobre la produccion electrica de los paneles, decido a la transferencia de calor del interior del invernadero. Ademas, se han ensayado dos separaciones diferentes y para cada una se ha comparado con la misma, utilizando un aislante sobre la cubierta. El estudio realizado sobre ambas instalaciones ha proporcionado un conocimiento profundo del funcionamiento de cada una de ellas, asi como informacion valida para una mejora de futuros disenos de instalaciones fotovoltaicas sobre cubiertas.

  1. Plan for a groundwater monitoring network in Taiwan

    NASA Astrophysics Data System (ADS)

    Hsu, Shiang-Kueen

    In Taiwan, rapid economic growth, rising standards of living, and an altered societal structure have in recent years put severe demands on water supplies. Because of its stable quantity and quality, groundwater has long been a reliable source of water for domestic, agricultural, and industrial users, but the establishment of a management program that integrates groundwater and surface-water use has been hampered by the lack of groundwater data. In 1992, the Department of Water Resources (DWR) initiated a program entitled "Groundwater Monitoring Network Plan in Taiwan." Under this program, basic groundwater data, including water-level and water-quality data, are being collected, and a reliable database is being established for the purpose of managing total water resources. This paper introduces the goals, implementation stages, and scope of that plan. The plan calls for constructing 517 hydrogeologic survey stations and 990 groundwater monitoring wells within 17 years. Under this program, water-level fluctuations are continuously monitored, whereas water-quality samples are taken for analysis only at the initial drilling stage and, subsequently, at the time when a monitoring well is being serviced. In 1996, the DWR and the Water Resources Planning Commission were merged to form today's Water Resources Bureau. R√©sum√© A Ta√Įwan, l'expansion √©conomique rapide, l'am√©lioration des conditions de vie et la transformation de la structure sociale ont provoqu√©, ces derni√®res ann√©es, une tr√®s forte demande en eau. Du fait de sa constance en qualit√© et en quantit√©, l'eau souterraine a longtemps √©t√© consid√©r√©e comme une ressource en eau s√Ľre pour les usages domestiques, agricoles et industriels. Mais la mise en place d'un programme de gestion int√©grant les utilisations d'eaux souterraines et de surface a √©t√© g√™n√©e par l'absence de donn√©es sur les eaux souterraines. En 1992, le D√©partement des Ressources en Eau a lanc√© le programme "Plan pour un r√©seau de suivi des eaux souterraines √† Ta√Įwan". D'apr√®s ce programme, les donn√©es de base concernant les eaux souterraines, comprenant les mesures de niveau et les donn√©es de qualit√©, ont √©t√© acquises ; une base de donn√©es s√Ľre est en cours d'√©laboration, dans le but de g√©rer l'ensemble des ressources en eau. Cet article pr√©sente les buts, les stades de d√©veloppement et une vue d'ensemble de ce plan. Le plan impose la mise en place de 517 stations de mesures hydrog√©ologiques et de 990 pi√©zom√®tres en 17 ans. Selon ce programme, les variations du niveau des nappes doivent √™tre suivies en continu, tandis que des √©chantillons pour la qualit√© de l'eau seront pr√©lev√©s pour analyses uniquement au cours de la phase de foration, puis au moment de la mise en service des pi√©zom√®tres. En 1996, le D√©partement des Ressources en Eau et la Commission de Planification des Ressources en Eau ont √©t√© r√©unis pour former l'actuel Bureau des Ressources en Eau. Resumen En Taiwan, el r√°pido crecimiento econ√≥mico, el aumento en el nivel de vida y los cambios sociales en los √ļltimos a√Īos han resultado en un aumento en la demanda de agua. Por su estabilidad en t√©rminos de cantidad y calidad, las aguas subterr√°neas han sido durante a√Īos la fuente de agua para usos dom√©sticos, agr√≠colas e industriales. En los √ļltimos a√Īos, sin embargo, el establecimiento de un programa de gesti√≥n conjunta de aguas superficiales y subterr√°neas se ha visto comprometido por la falta de datos correspondientes a estas √ļltimas. En 1992, el Departamento de Recursos de Agua (DWR) inici√≥ un programa titulado "Plan de Red de Control de Aguas Subterr√°neas en Taiwan". Bajo este programa, se est√°n recogiendo datos b√°sicos, incluyendo niveles piezom√©tricos y datos de calidad, y se est√° construyendo una base de datos con el prop√≥sito de gestionar los recursos de agua totales. Este art√≠culo presenta el marco, los objetivos y el estado de implantaci√≥n del plan, que pretende la construcci√≥n de 517 estaciones de medida hidrogeol√≥gicas y 990 pozos de observaci√≥n durante un periodo de 17 a√Īos. Bajo este programa, los niveles de agua se miden continuamente, mientras que las muestras para an√°lisis de calidad se toman s√≥lo durante la perforaci√≥n y cuando el pozo est√° en servicio. En 1996, el DWR y la Comisi√≥n de Planificaci√≥n de los Recursos de Agua se unieron para formar la actual Oficina de Recursos de Agua.5

  2. Chemical response to groundwater extraction southeast of Mexico City

    NASA Astrophysics Data System (ADS)

    Huizar-Alvarez, R.; Carrillo-Rivera, J. J.; √Āngeles-Serrano, G.; Hergt, T.; Cardona, A.

    An alternative procedure of pumping test data interpretation is used through a joint analysis of the standard time-drawdown curve and simultaneous field measurements of total dissolved solids (TDS); additional support is also provided by the temperature of extracted groundwater and the chemical composition of extracted water. The overall information was applied to characterise the groundwater flow system and its sources, the hydraulic conditions of the aquifer and hydraulic response of extraction boreholes. The analysis of this information suggests the presence of: (i) a local flow system that circulates at shallow depth through basalt units interstratified with fine grained sediments and pyroclastics; these materials contain water with TDS of 127-600 mg/L and Na of 24-178 mg/L, and temperature of 18-19.5 ¬įC (ii) intermediate flow in granular material under reducing conditions by the oxidation of organic matter in aquitard sediments; this water has TDS and Na values of 203-940 and 30-370 mg/L, respectively, and temperatures of about 20-22 ¬įC (iii) regional flow through volcanic rocks and limestone, with TDS content of 300-700 mg/L, Na of 80-230 mg/L and temperature of 23.0-24.8 ¬įC. The hydraulic response and the chemical composition of the water produced by some boreholes are affected by the seepage inflow from sewage effluents, the input from an overlying aquitard unit and the inducement of regional flow. The conception of the flow regime thus obtained allowed the recognition of hydraulic conditions which were more consistent with the hydrogeological setting, than if only a time vs. drawdown test analysis would have been carried out. L'interpr√©tation simultan√©e de pompages d'essais, des donn√©es de temp√©rature et r√©sidu sec (RS) de L'eau souterraine pomp√©e, mesur√©es simultan√©ment sur le terrain et la composition chimique de L'eau pomp√©e comme un aide additionnelle, est utilis√©e comme une diff√©rent proc√©dure pour interpr√©ter les pompages d'essais. La proc√©dure a √©t√© appliqu√©e pour caract√©riser le syst√®me d'√©coulement souterraine et sa source, les conditions hydrauliques de l'aquif√®re et la r√©ponse hydraulique des puits consid√©r√©. L'analyse de cette information sugg√©rer la pr√©sence des syst√®mes d'√©coulement suivantes. (i) local avec18 et 19.5 ¬įC de temp√©rature, RS de 127-600 mg/L, et Na de 24-178 mg/L, (ii) interm√©diaire avec une temp√©rature de 20 √° 22 ¬įC, le RS de 203-940 mg/L et Na 30-370 mg/L, (iii) r√©gional avec 300 √† 700 mg/L de RS et 80 √† 230 mg/L de Na, une temp√©rature de 23 √† 24.8 ¬įC. Dans le premier cas, l'eau traverse des roches basaltiques, dans le deuxi√®me, des s√©diments clastiques avec mati√®re organique de l'aquitard, dans le troisi√®me, des roches volcaniques et calcaires. La chimie de l'eau des quelques puits et sa r√©ponse hydraulique met en √©vidence l'influence de l'eau de L'aquitard, des effluents de surface et √©coulement r√©gional. La conception du r√©gime d'√©coulement obtenu, a permis reconna√ģtre les conditions hydrauliques des puits plus correspondantes au contexte hydrog√©ologique, que si uniquement les donn√©es rabattement vs temps auraient √©t√© analys√© La interpretaci√≥n conjunta de la gr√°fica de prueba de bombeo, valores de temperatura y s√≥lidos totales disueltos (STD) del agua subterr√°nea extra√≠da, medidos simult√°neamente en campo y la composici√≥n qu√≠mica del agua extra√≠da como apoyo adicional; se utiliz√≥ como un procedimiento alternativo para interpretar los datos de pruebas de bombeo. Toda esa informaci√≥n fue aplicada para caracterizar el sistema de flujo subterr√°neo y el origen de √©ste, las condiciones hidr√°ulicas del acu√≠fero y la respuesta hidr√°ulica de los pozos de extracci√≥n. El an√°lisis de la informaci√≥n indica la presencia de: (i) flujo local con temperatura de 18-19.5 ¬įC, STD de 127-600, y Na de 24-178 mg/L (ii) flujo intermedio con temperatura de 20-22 ¬įC, los STD y Na son de (203-940 y 30-370 mg/L), respectivamente; (iii) regional con STD de 300-700 y Na de 80-230 mg/L, y temperatura de 23-24.8 ¬įC. En el primer caso el agua circula a trav√©s de rocas bas√°lticas, en el segundo viaja por material granular y materia org√°nica en sedimentos del acuitado. El flujo regional circula por material volc√°nico y rocas calizas. La respuesta hidr√°ulica y la composici√≥n qu√≠mica del agua extra√≠da por algunos pozos, es afectada por infiltraci√≥n de efluentes de agua residual, entrada de agua del acuitardo sobreyacente y la inducci√≥n de flujo regional. La concepci√≥n del r√©gimen de flujo obtenida, permiti√≥ reconocer a las condiciones hidr√°ulicas de los pozos, m√°s correspondientes con el contexto hidrogeol√≥gico, que s√≠ √ļnicamente se hubieran analizado los datos de abatimiento vs tiempo.

  3. Three-dimensional mathematical model to simulate groundwater flow in the lower Palar River basin, southern India

    NASA Astrophysics Data System (ADS)

    Senthilkumar, M.; Elango, L.

    A three-dimensional mathematical model to simulate regional groundwater flow was used in the lower Palar River basin, in southern India. The study area is characterised by heavy ion of groundwater for agricultural, industrial and drinking water supplies. There are three major pumping stations on the riverbed apart from a number of wells distributed over the area. The model simulates groundwater flow over an area of about 392 km2 with 70 rows, 40 columns, and two layers. The model simulated a transient-state condition for the period 1991-2001. The model was calibrated for steady- and transient-state conditions. There was a reasonable match between the computed and observed heads. The transient model was run until the year 2010 to forecast groundwater flow under various scenarios of overpumping and less recharge. Based on the modelling results, it is shown that the aquifer system is stable at the present rate of pumping, excepting for a few locations along the coast where the groundwater head drops from 0.4 to 1.81 m below sea level during the dry seasons. Further, there was a decline in the groundwater head by 0.9 to 2.4 m below sea level in the eastern part of the area when the aquifer system was subjected to an additional groundwater withdrawal of 2 million gallons per day (MGD) at a major pumping station. Les mod√®les math√©matiques en trois dimensions de l'√©coulement souterrain r√©gional sont tr√®s utiles pour la gestion des ressources en eau souterraine, car ils permettent une √©valuation des composantes des processus hydrologiques et fournissent une description physique de l'√©coulement de l'eau dans un aquif√®re. Une telle mod√©lisation a √©t√© entreprise sur une partie du bassin inf√©rieur de la rivi√®re Palar, dans le sud de l'Inde. La zone d'√©tude est caract√©ris√©e par des pr√©l√®vements importants d'eau souterraine pour l'agriculture, l'industrie et l'eau potable. Il existe trois grandes stations de pompage sur la rivi√®re en plus d'un certain nombre de puits r√©partis dans cette r√©gion. Le mod√®le simule l'√©coulement souterrain dans une r√©gion d'environ 392 km2 avec 70 rangs, 40 colonnes et deux couches. Le mod√®le a fonctionn√© en r√©gime transitoire en utilisant une approximation aux diff√©rences finies d'une √©quation diff√©rentielle partielle en trois dimensions de l'√©coulement souterrain dans cet aquif√®re pour la p√©riode 1991-2001. Le mod√®le a √©t√© calibr√© pour des conditions de r√©gime permanent et transitoire. Les charges hydrauliques calcul√©es √©taient en bon accord avec celles observ√©es. Sur la base des r√©sultats du mod√®le, il est apparu que le syst√®me aquif√®re est stable pour ce taux de pompage, except√© en quelques sites le long de la c√īte o√Ļ l'eau marine a p√©n√©tr√© 50-100 m dans les terres. Le mod√®le transitoire a tourn√© jusqu'en 2010 afin de pr√©voir l'√©coulement souterrain dynamique pour diff√©rents sc√©narios de pompage excessif et de recharge r√©duite. Il se produit un abaissement de la pi√©zom√©trie de la nappe de 0.6 √† 0.8 m dans la partie orientale, alors que l'aquif√®re est soumis √† un pr√©l√®vement suppl√©mentaire de 8,000 m3/jour √† l'une des stations principales de pompage. M√™me avec le niveau actuel de pompage, la pi√©zom√©trie de la nappe descendrait sous le niveau de la mer au cours des saisons s√®ches. Le mod√®le pr√©dit le fonctionnement du syst√®me aquif√®re sous diff√©rentes conditions de stress hydrologique. Los modelos tridimensionales de flujo de aguas subterr√°neas son √ļtiles para gestionar los recursos h√≠dricos subterr√°neos, ya que proporcionan una aproximaci√≥n a los diversos procesos hidrol√≥gicos y una descripci√≥n cuantitativa del flujo de agua en el acu√≠fero. Se ha desarrollado un estudio de modelaci√≥n de este tipo en una parte de la cuenca baja del r√≠o Palar, en el Sur de la India. Esta zona se caracteriza por las intensas extracciones de aguas subterr√°neas para usos agr√≠colas, industriales y dom√©sticos. Hay tres estaciones de bombeo principales en el r√≠o, adem√°s de numerosos pozos distribuidos por la zona. El modelo simula el flujo de las aguas subterr√°neas en una superficie de 392 km2 por medio de 70 filas, 40 columnas y 2 capas. El modelo ha sido empleado en condiciones transitorias, por medio de la aproximaci√≥n en diferencias finitas de las ecuaciones diferenciales parciales en tres dimensiones del flujo en el acu√≠fero durante el per√≠odo 1991-2001. Se ha calibrado el modelo en condiciones permanentes y transitorias. El ajuste entre los niveles calculados y medidos es razonable. A partir de los resultados de la modelaci√≥n, se ha obtenido que el sistema acu√≠fero es estable con la tasa de bombeo utilizada, exceptuando unos pocos emplazamientos a lo largo de la costa, donde se ha dado lugar a fen√≥menos de intrusi√≥n marina en una distancia de 50-100 m. El modelo transitorio ha sido ejecutado hasta el a√Īo 2010 para predecir el flujo din√°mico bajo diversos escenarios de sobreexplotaci√≥n y de reducci√≥n de la recarga. Se produce una disminuci√≥n en los niveles piezom√©tricos de 0.6 a 0.8 m en la zona oriental, donde el sistema acu√≠fero est√° sometido a una extracci√≥n adicional de 2 millones de galones por d√≠a en la estaci√≥n principal de bombeo. Incluso con las extracciones actuales, los niveles piezom√©tricos se sit√ļan bajo el nivel del mar durante las √©pocas secas. El modelo predice el comportamiento de este sistema acu√≠fero bajo varias condiciones de presi√≥n hidrol√≥gica.

  4. European team gauges a gamma-ray star

    NASA Astrophysics Data System (ADS)


    Italian astrophysicists have pushed the Hubble Space Telescope to the limit of its powers in finding the distance of Geminga, a pointlike object 500 light-years from the Earth. It is the prototype of a novel kind of star, a radio-silent neutron star, which may be much more common in the Universe than previously supposed. Geminga is so weak in visible light that Hubble had to stare at the spot for more than an hour to register it adequately. The object is nevertheless one of the brightest sources of gamma-rays in the sky, and its output of this very energetic form of radiation can now be accurately ganged. Neutron stars, first discovered as radio pulsars in 1967, are fantastic creations of exploding stars, just one step short of a black hole. They are heavier than the Sun yet only about twenty kilometres wide. Made of compressed nuclear matter, they have gravity and magnetic fields many billions of times stronger than on the Earth. With the first direct measurement of the distance of a radio-silent neutron star, astrophysicists can assess Geminga's power and speed of motion. The astronomical task was like judging the width of a one- franc piece in Paris, seen from the distance of Sicily. Geminga's low brightness greatly aggravated the difficulties. Patrizia Caraveo and her colleagues at the Istituto di Fisica Cosmica in Milan arranged for Hubble's wide-field camera (WFPC2) to make its prolonged observations of Geminga three times. Their findings will be published in Astrophysical Journal Letters on 20 April 1996. Caraveo's co-authors are Giovanni Bignami and Roberto Mignani of Milan, and Laurence Taff of Johns Hopkins University, Maryland. The Italians took advantage of the European Space Agency's collaboration with NASA in the Hubble mission, which gives European astronomers privileged access to the Space Telescope. Shifts of millionths of a degree The three sightings of Geminga, made at intervals of six months, revealed small shifts in the position of the faint neutron star. The background of a few brighter but more distant stars displayed by Hubble's camera provided a frame of reference. In the course of a year, Geminga moved northeastwards by 0.17 arc-seconds, equivalent to one degree in 21,000 years. That was due to Geminga's high-speed motion through the Galaxy. But the neutron star also seemed to shift to either side of its interstellar track, because of changes in Hubble's viewpoint as the Earth orbited around the Sun. At opposite seasons, spring and autumn in this case, the Earth is on opposite sides of the Sun, at vantage points 300 million kilometres apart. As a result, the bearings of stars change a little, by the effect called parallax. Nearby stars shift more than very distant stars, and astronomers can measure their distances by trigonometry. The sideways displacement measured using the Hubble Space Telescope was 0.00636 arc-seconds, less than two millionths of a degree. From this figure the astronomers calculate that Geminga is 512 light-years away (157 parsecs) with an uncertainty of the order of 100 light-years. The strong gamma-rays and weak light observed today left Geminga around the time that Columbus discovered America. "We are pleased to have measured a parallax for an object at the limit of detection, which was never done before," says Patrizia Caraveo. "But what really matters is that we have pinned down an important object that has puzzled us for more than 20 years." From "it's not there" to "here it is" Geminga has tested the patience of the Milanese astronomers for twenty years. NASA's shortlived SAS-2 satellite (1973) first recorded a mysterious source of gamma-rays in the constellation of Gemini. In 1976 Giovanni Bignami named it Geminga. This is a pun signifying either "Gemini gamma" or "gh'è minga" which in the Milanese argot means "it's not there". Geminga lived up to its name when Bignami and his colleagues looked in vain for radio emissions from it. By 1981, data from ESA's longlived gamma-ray satellite COS-B had defined the position of the gamma-ray source to within half a degree -- well enough to prompt renewed efforts to identify it. Radio searches still drew a blank, but in the early 1980s Bignami and others found X-rays coming from Geminga in observations with NASA's Einstein satellite. They narrowed down Geminga's position to within a twentieth of a degree. There was no obvious counterpart to Geminga in visible light. Between 1983 and 1987 the Milanese team hunted for it with large telescopes in Hawaii and Chile. Eventually they selected a very faint object, peculiar in colour, as the visible Geminga. In 1992 a further sighting from Chile established Geminga's rate of movement across the sky. Meanwhile, the German/US/UK satellite Rosat revealed that Geminga pulsates in X-rays four times a second -- every 237 milliseconds to be precise. The same pulsation was found in gamma-rays by NASA's Gamma-Ray Observatory. Bignami and his colleagues then returned to the gamma-ray data from ESA's COS-B. They found the pulsation hidden there too and were able to compute the slowdown in Geminga's pulse-rate. From the slowdown they estimated the age of Geminga at 340,000 years. The distance measurement completes the gradual transformation of the enigmatic gamma-ray source into a well-characterized object. The Italian team calculates that Geminga is travelling at a speed of at least 120 kilometres per second. The neutron star's radiation in gamma-rays and X-rays is equivalent in energy to ten times the visible light of the Sun. More importantly, the way in which the neutron star distributes its energy output at different wavelengths is now known. "Neutron stars are radio sources for only a small fraction of their lives," says Giovanni Bignami. "So while we know 700 pulsars, there are probably millions of radio-silent neutron stars like Geminga. Thousands of them may be among X-ray sources already known but so far unidentified. I look forward to searching for new Gemingas with EPIC, our set of X-ray cameras in ESA's XMM satellite due for launch in 1999." The Hubble Space Telescope is a project of international cooperation between NASA and the European Space Agency (ESA). The Space Telescope Science Institute is operated by the Association of Universities for Research in Astronomy, Inc. (AURA), for NASA, under contract with the Goddard Space Flight Center, Greenbelt, MD. Patrizia A. Caraveo - Istituto di Fisica Cosmica del CNR, Via Bass 20133 - MILANO (Italy) Giovanni F. Bignami - Istituto di Fisica Cosmica del CNR, Via Bass - 20133-MILANO (Italy) Dipartimento di Ingegneria Industriale, Univ. of Cassino, CASSINO, Roberto Mignani - Istituto di Fisica Cosmica del CNR, Via Bassini, 20133-MILANO (Italy) Universita di Milano, Italy Laurence G. Taff - Department of Physics and Astronomy, JHU, BALTIMORE (MD Research Supported in part by General Observer Grant GO 5484.01-93

  5. ESO Council Visits First VLT Unit Telescope Structure in Milan

    NASA Astrophysics Data System (ADS)


    As the ESO Very Large Telescope (VLT) rapidly takes on shape, Europe has just come one step closer to the realisation of its 556 million DEM astronomical showcase project. Last week, the ESO Council held its semi-annual meeting in Milan (Italy) [1]. During a break in the long agenda list, Council members had the opportunity to visit the Ansaldo factory in the outskirts of this city and to see for the first time the assembled mechanical structure of one of the four 8.2-metre VLT Unit telescopes. This Press Release is accompanied by a photo that shows the ESO Council delegates in front of the giant telescope. After a long climb up the steep staircase to the large Nasmyth platform at the side of the telescope where the astronomical instruments will later be placed, Dr. Peter Creola (Switzerland) , President of the ESO Council and a mechanics expert, grabbed the handrail and surveyed the structure with a professional eye: `I knew it was going to be big, but not that enormous!', he said. Other delegates experienced similar feelings, especially when they watched the 430 tonnes of steel in the 24-metre tall and squat structure turn smoothly and silently around the vertical axis. The Chairman of the ESO Scientific Technical Committee (STC), Dr. Johannes Andersen (Denmark) , summarized his first, close encounter with the VLT by `This is great fun!' and several of his colleague astronomers were soon seen in various corners of the vast structure, engaged in elated discussions about the first scientific investigations to be done with the VLT in two years' time. The VLT Main Structures The visit by Council took place at the invitation of Ansaldo Energia S.p.A. (Genova), EIE-European Industrial Engineering S.r.I. (Venice) and SOIMI-Societa Impianti Industriale S.p.A. (Milan), the three Italian enterprises responsible for the construction of the main structures of the VLT 8.2-metre Unit telescopes. Short speeches were given on this occasion by Drs. Ferruccio Bressani (Ansaldo), Luigi Guiffrida (SOIMI), Gianpietro Marchiori (EIE) and Prof. Massimo Tarenghi (ESO), describing the very successful implementation of this major VLT contract that was awarded by ESO in September 1991 [2]. All speakers praised the good collaboration between ESO and its industrial partners and Prof. Riccardo Giacconi , Director General of ESO, expressed his satisfaction `with the splendid performance of the ESO-Industry team which was bringing us close to the realisation of the premier telescope array in optical ground-based astronomy in the world'. The participants were also pleased to listen to several of the Italian engineers present who commented on the very positive experience of being personally involved in the world's largest telescope project. The VLT telescope structures incorporate many new technological concepts. Thanks to these and careful planning of the many components and their integration, it has been possible to achieve, among others, light weight construction, high mechanical stiffness, good thermal equilibrium with the ambient air (of importance for the seeing during the observations), low electromagnetic emissitivity (i.e. low interference with the sensitive astronomical instruments) and easy maintainability. Of particular interest is also the giant, direct drive system with a diameter of 9 metres and the sophisticated, innovative laser encoder system. In this way, there is no direct contact between the moving parts and the friction during the rotation is kept at an absolute minimum. The Next Steps The ESO VLT project is now entering into a decisive phase and the next years will see an increasing number of telescope parts and instruments from the scientific and industrial laboratories of Europe converging towards the VLT observatory at Cerro Paranal in Chile. It is gratifying that, despite its high degree of complexity and incorporation of a substantial number of new technologies, the project is within schedule and budget. There will be several important milestones in 1996. During the next two months, the mounting of the mechanical structure in Milan will be completed. Following this, a group of ESO hard- and software experts will spend about 6 months next to it, implementing and thoroughly testing all aspects of the very advanced VLT telescope control system. In the meantime, the erection of the first telescope enclosure at Paranal is rapidly proceeding and the outside panelling will soon be put in place. This work will be completed in January 1996, after which the integration of all inside mechanical components will follow. The take-over by ESO of the fully operational, first enclosure is scheduled for May 1996. The other enclosures will become ready at regular intervals thereafter. In Milan, all of the heavy parts of the second telescope structure have already been produced and the third and fourth are about 60 percent complete. While the first structure has now been pre-assembled for tests, the individual parts of the second will not be put together before they are shipped to Paranal in early 1996. Starting in June 1996, they will then be assembled inside the completed, first enclosure. Thus, the `second' structure will become the `first' VLT Unit telescope (UT1). This work will last until early 1997, after which the first 8.2-metre mirror will arrive from Europe and be installed. Finally, after another test and optimisation period, `first light' for UT1 is expected in late 1997. This procedure is very advantageous, because it allows to continue under less time pressure the extensive tests on the `first' structure in Milan until a satisfactory state of debugging and optimisation of the new VLT control system has been reached. In this way, the time necessary for the installation of this system in UT1 at Paranal in 1997 will be significantly shortened. In fact, the structure seen by the ESO Council in Milan will be the last to be shipped to Paranal where it will then become the fourth 8.2-metre Unit telescope (UT4). Mirrors and Instruments As earlier announced, ESO officially received the first 8.2-metre VLT mirror from REOSC in Paris [3] on November 21. The polishing of the second mirror has already started and, based on the experience gained with the first, it is expected that this work will be accomplished in less time. The third blank is already at REOSC and the fourth will soon be ready at Schott Glaswerke in Mainz (Germany). Following extended studies, and as yet another move towards new technology within the VLT project, it has now been decided to make the 1.2-metre secondary VLT mirrors of beryllium, a very light, exotic metal. The contracting firm is Dornier of the DASA group (Germany). This saves much weight and allows these relatively large mirrors to be efficiently used in the `chopping and tilting' mode needed for observations in the infrared wavelength region as well as for the critical, image-sharpening adaptive optics system. Significant progress has also been achieved on the first astronomical instruments which will be installed at the VLT. The integration of the first two of these, ISAAC and CONICA which will be installed on UT1 in the course of 1997, has already started in the ESO laboratories at the Headquarters in Garching. Important advances have also taken place within the FORS (managed by a consortium of Landessternwarte Heidelberg, Universitaets-Sternwarte Goettingen and Institut fuer Astronomie und Astrophysik der Ludwig Maximilians Universitaet Muenchen) and FUEGOS (Paris Observatory, Meudon Observatory, Toulouse Observatory, Geneva Observatory and Bologna Observatory) projects. More details about these and other VLT instruments will be given in later communications. Notes: [1] The Council of ESO consists of two representatives from each of the eight member states. It is the highest legislative authority of the organisation and normally meets twice a year. This time, Council was invited to Milan by the Director of the Osservatorio di Brera (Milan), Prof. Guido Chincarini, and the Italian delegation. [2] See ESO Press Release 08/91 of 24 September 1991. [3] See ESO Press Release 15/95 of 13 November 1995. How to obtain ESO Press Information ESO Press Information is made available on the World-Wide Web (URL: ESO Press Photos may be reproduced, if credit is given to the European Southern Observatory.

  6. Participatory groundwater management in Jordan: Development and analysis of options

    NASA Astrophysics Data System (ADS)

    Chebaane, Mohamed; El-Naser, Hazim; Fitch, Jim; Hijazi, Amal; Jabbarin, Amer

    Groundwater over-exploitation has been on the rise in Jordan. Competing demands have grown in the face of perennial water shortages, a situation which has been exacerbated by drought conditions in the past decade. This paper reports findings of a project in which management options to address over-exploitation were developed for one of Jordan's principal aquifer systems, the Amman-Zarqa Basin. Options for addressing the situation were developed through a participatory approach that involved government officials and various public and private sector interest groups. Particular efforts were made to involve well irrigators, who are likely to be heavily impacted by the changes required to reduce groundwater pumping to a sustainable level. With information obtained from a rapid appraisal survey as well as from interviews with farmers, community groups, government officials, and technical experts, an extensive set of options was identified for evaluation. Based on integrated hydrogeologic, social, and economic analysis, five complementary management options were recommended for implementation. These included the establishment of an Irrigation Advisory Service, buying out farm wells, placing firm limits on well ion and irrigated crop areas, exchanging treated wastewater for groundwater, and measures to increase the efficiency of municipal and industrial water use. Various combinations and levels of these options were grouped in scenarios, representing possible implementation strategies. The scenarios were designed to assist decision makers, well owners and other stakeholders in moving gradually towards a sustainable ion regime. Social and economic aspects of each option and scenario were analyzed and presented to stakeholders, together with a of legal, institutional and environmental ramifications. Combining scientific analysis with a participatory approach in the Amman Zarqa Basin groundwater management was devised as a prototype to be used in the management of other groundwater basins in Jordan. This participatory management approach would also be useful in other parts of the world that are experiencing similar groundwater over-exploitation problems. La surexploitation des eaux souterraines prend de l'importance en Jordanie. Les demandes en concurrence ont augment√© face √† des d√©ficits permanents d'eau, situation qui a √©t√© exacerb√©e par la s√©cheresse de la derni√®re d√©cennie. Cet article rend compte de l'aboutissement d'un projet dans lequel des options de gestion portant sur la surexploitation ont √©t√© d√©velopp√©es pour l'un des principaux syst√®mes aquif√®res de Jordanie, le bassin d'Amman Zarqa. Des options pour aborder cette situation ont √©t√© d√©velopp√©es gr√Ęce √† une approche participative qui implique des fonctionnaires du gouvernement et des groupes d'int√©r√™ts vari√©s des secteurs public et priv√©. Des efforts particuliers ont √©t√© faits pour impliquer les irrigants utilisant des puits, qui sont probablement ceux qui ont le plus fort impact sur les changements attendus permettant de remettre le syst√®me en √©quilibre. √Ä partir des informations obtenues de campagnes rapides d'√©valuation, telles que des r√©unions de communaut√©s et des entrevues avec des experts techniques du gouvernement, un large jeu d'options a √©t√© identifi√© pour l'√©valuation. Bas√©es sur une analyse hydrog√©ologique, sociale et √©conomique, cinq options compl√©mentaires de gestion ont √©t√© recommand√©es pour la r√©alisation. Ce sont la cr√©ation d'un Service Consultatif d'Irrigation, achetant les puits agricoles, fixant des limites fermes aux pr√©l√®vements des puits et aux zones irrigu√©es, √©changeant les eaux us√©es trait√©es avec des eaux souterraines, et la mise en place de mesures pour accro√ģtre l'efficacit√© des usages collectifs et industriels. Des combinaisons et des niveaux vari√©s de ces options ont √©t√© regroup√©s en sc√©narios, pr√©sentant les strat√©gies possibles de mise en Ňďuvre. Les sc√©narios ont √©t√© mis au point pour assister les d√©cideurs, les propri√©taires de puits et les autres acteurs pour atteindre progressivement un r√©gime de pr√©l√®vement durable. Les aspects sociaux et √©conomiques de chaque option et de chaque sc√©nario ont √©t√© analys√©s et pr√©sent√©s aux acteurs, en m√™me temps qu'un r√©sum√© des ramifications l√©gales, institutionnelles et environnementales. En combinant une analyse scientifique √† une approche participative du bassin d'Amman Zarqa, la gestion des eaux souterraines a √©t√© imagin√©e comme un prototype pouvant √™tre utilis√© pour la gestion d'autres bassins aquif√®res de Jordanie. Il peut √©galement √™tre utile √† d'autres r√©gions du monde qui sont concern√©es par des probl√®mes similaires de surexploitation des eaux souterraines. La sobreexplotaci√≥n de las aguas subterr√°neas ha ido en aumento en Jordania, donde las demandas en competici√≥n han crecido frente a una escasez perenne de agua, situaci√≥n que ha sido agravada por el estado de sequ√≠a de la √ļltima d√©cada. Este art√≠culo presenta los hallazgos de un proyecto en el que se han desarrollado opciones de gesti√≥n para hacer frente a la sobreexplotaci√≥n en uno de los principales sistemas acu√≠feros de Jordania: la cuenca de Amm√°n-Zarga. Se ha elaborado opciones para afrontar la situaci√≥n mediante un enfoque participativo que incluye a personal del gobierno y a diversos grupos de inter√©s de los sectores p√ļblico y privado. En particular, se ha intentado involucrar a los regantes que se sirven de aguas subterr√°neas, quienes tienen m√°s probabilidad de ser directamente afectados por los cambios requeridos para devolver el sistema a un balance equilibrado. A partir de la informaci√≥n obtenida en r√°pidas campa√Īas de valoraci√≥n, as√≠ como de encuentros con la comunidad y entrevistas con los expertos t√©cnicos del gobierno, se ha identificado un amplio conjunto de opciones para su evaluaci√≥n. Bas√°ndose en un an√°lisis integrado de los aspectos hidrogeol√≥gicos, sociales y econ√≥micos, se ha recomendado la implementaci√≥n de cinco opciones complementarias de gesti√≥n: establecimiento de un Servicio Asesor de Riego; adquisici√≥n de pozos de granjas; imposici√≥n de l√≠mites estrictos en las extracciones de pozos y superficies de riego; substituci√≥n de las aguas subterr√°neas con aguas residuales depuradas; y medidas para incrementar la eficiencia de los usos municipales e industriales del agua. Se ha agrupado varias combinaciones y niveles de dichas opciones en escenarios, representando estrategias posibles de implementaci√≥n. Los escenarios han sido dise√Īados para ayudar a los gestores en la toma de decisiones, a los propietarios de pozos y a otros agentes para que se vaya consiguiendo de forma gradual un r√©gimen de extracciones sustentable. Se ha analizado los aspectos sociales y econ√≥micos de cada opci√≥n y de cada escenario, present√°ndolos a los diversos agentes, adem√°s de generar un resumen de ramificaciones legales, institucionales y medioambientales. Se ha concebido la combinaci√≥n de un an√°lisis cient√≠fico con un enfoque participativo en la cuenca de Amm√°n-Zarga como un prototipo de gesti√≥n de las aguas subterr√°neas que puede ser aplicado a la gesti√≥n de otras cuencas en Jordania. Tambi√©n ser√≠a √ļtil en otros lugares del mundo que est√©n experimentando problemas similares de sobreexplotaci√≥n de los recursos h√≠dricos subterr√°neos.