890 research outputs found

    Use of metamodels in real-time operation of water distribution systems

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    Published16th Water Distribution System Analysis Conference, WDSA2014 — Urban Water Hydroinformatics and Strategic PlanningThis paper presents a methodology for real-time pump scheduling in water distribution system. The methodology uses an optimizer linked to other two modules: one to predict the hydraulic behavior of the system and another to forecast the demands. A metamodel is used instead of a traditional hydraulic simulator to speed up relevant computations, i.e. evaluations of large number of candidate pump schedules generated during the optimization process. The methodology presented is applied to a real-life water distribution system in Brazil. The results obtained show that the use of metamodel can generate low cost pump schedules in a computationally fast manner.The authors acknowledge the support from the São Paulo Research Foundation (FAPESP), from the Coordination for the Improvement of Higher Education (CAPES) and from the Brazilian Scientific and Technological Development Council (CNPq) for providing the PhD's scholarship and Grant to the second author, and also from the Araraquara’s Autonomous Department of Water and Sewage (DAAE-Araraquara, SP, Brazil) for providing data and assistance through the agreement between the company and the University of São Paulo

    Real-time multiobjective optimization of operation of water supply systems

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    The need for more efficient use of energy in water distribution systems is increasing constantly due to increasing energy prices. A new methodology for optimized real-time operation of a water distribution system is developed and presented here. The methodology is based on the integration of three models: (1) real-time demand forecasting model, (2) hydraulic simulation model of the system, and (3) optimization model. The optimization process is driven by the cost minimization of the energy used for pumping and the maximization of operational reliability. The latter is quantified using alternative measures into the optimization process in order to mimic the conservative attitude to pump scheduling often adopted by control room operators in real-life systems. Optimal pump schedules were generated by using a multialgorithmgenetically- adaptive-method (AMALGAM), hydraulic simulations are performed by using the EPANET2 model, and demand forecasting was performed by using the recently developed DAN2-H model. A number of other methodological developments are used to enable pump scheduling in real time. The new methodology is tested, verified, and demonstrated on the water distribution system of Araraquara, in the state of São Paulo, Brazil. The results obtained demonstrate that it is possible to achieve substantial energy cost savings (up to 13% relative to historical system operation) while simultaneously maintaining the level of supply reliability obtained by manually operating the water system.São Paulo Research Foundation (FAPESP)Coordination for the Improvement of Higher Education (CAPES)Brazilian Scientific and Technological Development Council (CNPq)Araraquara’s Autonomous Department of Water and Sewage (DAAE-Araraquara, SP, Brazil

    Pleuroamniotic shunting--case report

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    Fetal hydrothorax refers to a collection of fluid within the fetal thorax that may be the result of chylous leak from the thoracic duct (primary hydrothorax) or generalized fluid retention associated with immune or no immune fetal hydrops (secondary hydrothorax). The authors' presents a case report occurred in 2002, of a pregnant woman that at 25 weeks' gestation that was referred to Maternidade Bissaya-Barreto-Coimbra because of a fetal hydrothorax at left, under tension and with cardiac decompensation signs. A fetal thoracocentesis was performed and the diagnosis was chylothorax. Because of a rapid reaccumulation of fluid a pleuroamniotic shunt was placed. The effusion and the cardiac decompensation signs regressed. The delivery was at 38 weeks' gestation. The newborn had been stable. Actually he has 10 months, is healthy and has a normal grow and development

    Cuidado de enfermagem para enfermeiros docentes na perspectiva da complexidade

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    O cuidado de enfermagem complexo é condição essencial para a compreensão do ser humano como singular e multidimensional. Assim, objetivou-se conhecer o significado do cuidado de enfermagem para enfermeiros docentes, na perspectiva da complexidade. Trata-se de uma pesquisa qualitativa, realizada com sete enfermeiros docentes deum curso de enfermagem de nível superior da região central do Rio Grande do Sul, Brasil. Os dados foram coletados no mês de novembro de 2011, por meio do grupo focal, a partir de três encontros, sistematizados com temáticas que contemplassem o objetivo deste estudo. Para a análise de dados, foi utilizada a análise textual discursiva. Os resultados evidenciaram o cuidado de enfermagem como construção singular que vai além de um cuidado técnico-prescritivo, pontual e linear. Conclui-se que o cuidado de enfermagem não pode ser concebido como açãoreducionista, mas como construção singular, que envolve interações, reflexões e autoconhecimento

    The luminosity function of field galaxies

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    Schmidt's method for construction of luminosity function of galaxies is generalized by taking into account the dependence of density of galaxies from the distance in the near Universe. The logarithmical luminosity function (LLF) of field galaxies depending on morphological type is constructed. We show that the LLF for all galaxies, and also separately for elliptical and lenticular galaxies can be presented by Schechter function in narrow area of absolute magnitudes. The LLF of spiral galaxies was presented by Schechter function for enough wide area of absolute magnitudes: . Spiral galaxies differ slightly by parameter . At transition from early spirals to the late spirals parameter in Schechter function is reduced. The reduction of mean luminosity of galaxies is observed at transition from elliptical galaxies to lenticular galaxies, to early spiral galaxies, and further, to late spiral galaxies, in a bright end, . The completeness and the average density of samples of galaxies of different morphological types are estimated. In the range the mean number density of all galaxies is equal 0.127 Mpc-3.Comment: 14 page, 8 figures, to appear in Astrophysic
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