Numerical Modeling Applied to Leachate Generation using Hydrus - Case Study: Seropédica, Rio de Janeiro, Brazil / Modelagem numérica aplicada à geração de lixiviado usando Hydrus - Estudo de Caso: Seropédica, Rio de Janeiro, Brasil

ABSTRACT Improper design and management of the cover layer of a sanitary landfill has been proven to produce harmful environmental impacts on the environment. One alternative at hand is to develop scenarios based on simulation of physical and computational models to represent the expected field water balance of a landfill coverage layer. This paper investigates the design of a sanitary landfill final cover in the municipality of Seropédica, which is located at the state of Rio de Janeiro - Brazil. More specifically, the compact soil coverage, which is widely used for landfill final cover of municipal solid waste, is evaluated in contrast to vegetation cover by grass, vegetation cover by brachiaria and capillary barrier. To accomplish such task, hydrometeorological forcing conditions, namely daily rainfall and temperature, were retrieved from the Anchieta weather station, which is situated nearby the study area. The Hydrus 1D and 2/3 D computational codes were employed to develop a set of scenarios to follow the contamination plume evolution within the landfill along the time frame of 20 years with some degree of reliability. It should be noted that the performed evaluation indicates the possibility to control the leachate release and consequently to avoid contaminating the environment, notably to prevent soil and water resources pollution. Vegetation cover by grass and brachiaria showed important control mechanisms with respect to the movement of the contaminant plume. In addition, it should be noticed that the best results for the landfill final cover were achieved for the capillary barrier, while poor performance results were obtained for the commonly employed compact soil.

RESUMO O projeto e a gestão inadequados da camada de cobertura de um aterro sanitário produzem impactos ambientais prejudiciais ao meio ambiente. Uma alternativa disponível é desenvolver cenários baseados na simulação de modelos físicos e computacionais para representar o balanço hídrico que se espera que ocorra em uma camada de cobertura do aterro por meio de um experimento de campo. O presente trabalho investiga o projeto de cobertura final de um aterro sanitário no município de Seropédica, localizado no estado do Rio de Janeiro - Brasil. Mais especificamente, a cobertura compacta do solo, que é amplamente utilizada para a cobertura final de aterro de resíduos sólidos urbanos, é avaliada em contraste com a cobertura vegetal por gramíneas, cobertura vegetal por braquiária e barreira capilar. Para realização dessa tarefa, forçantes hidrometeorológicas, nomeadamente precipitação e temperatura na escala diária, foram obtidas da estação meteorológica de Anchieta, situada nas proximidades da área de estudo. Os códigos computacionais Hydrus 1D e 2/3 D foram empregados para desenvolver um conjunto de cenários para acompanhar a evolução da pluma de contaminação no interior do aterro ao longo do período de 20 anos com algum grau de confiabilidade. Ressalta-se que a avaliação realizada indica a possibilidade de controlar a liberação de chorume e, consequentemente, de evitar a contaminação do meio ambiente, notadamente para prevenir a poluição do solo e dos recursos hídricos. A cobertura vegetal por gramíneas e braquiárias apresentou importantes mecanismos de controle com relação ao movimento da pluma contaminante. Além disso, deve-se notar que os melhores resultados para a cobertura final do aterro foram alcançados para a barreira capilar, enquanto que os resultados de baixo desempenho foram obtidos para o solo compacto comumente empregado.

Modeling and simulation of transmission dynamics of syphilis in Bayinguoleng Mongolia Autonomous Prefecture of Xinjiang / 中华地方病学杂志

Objective By analyzing the data of new syphilis cases from 2008 to 2014 in Bayinguoleng Mongolia Autonomous Prefecture (Bazhou for short) of Xinjiang to further provide reference basis for setting up control strategies.Methods Using the new syphilis data reported in Bazhou of Xinjiang,we constructed a dynamic model of transmission dynamics of syphilis,and the model was simulated and quantitatively analyzed.Results The syphilis dynamical model was introduced,the methods of setting the relevant parameters were given.It was found that the established model fitted well (MA PE =1.59％,RMSPE =0.68％),and the basic reproduction number of outbreak epidemic was estimated to be R0 =1.06 (95％ CI:1.01-1.15),it was predicted that the cumulative incidence of syphilis in Bazhou was 18 145 cases by 2024.In 2023,the cumulative number of cases was 16 465,and the number of new cases reached 1 680 in 2024.The infection rate,the number of core group partners and the treatment rate were main factors influencing the prevalence of syphilis after comparison of the sensitivity of the model parameters.Conclusion There is still an upward trend in the prevalence of syphilis infection in Bazhou of Xinjiang,and relevant departments should strengthen the prevention and control measures in high-risk groups,promote the use of condoms and other comprehensive intervention measures to control the prevalence of syphilis.

Effects of sand therapy temperature on the bone reconstruction and numerical study on the heat transfer / 中国实验动物学报

Objective To investigate the effects of sand therapy temperature on bone reconstruction and numerical study on the heat transfer.Methods CT scan imaging was performed respectively for four times(before and after OA model was set up,and after the first and second weeks during the sand therapy).Import the scan data to MIMICS software,and the changes of femoral bone mass layer were analyzed.After combining the muscle,femur,bone marrow and meshing,the established three-dimensional model of the STL format was introduced into the COMSOL software for heat transfer simulation and effect of stress on bone remodeling induced by temperature field.Results Changes of four CT scan data were analyzed.The soft bone volume was reduced,while the dense and hard bone volume were increased.Numerical simulation on the heat transfer showed the temperature distribution of the thigh and the femur.Conclusions The thermal stress produced by sand therapy temperature exert promoting effect on the femur bone remodeling.

Hidrodinámica aplicada a la gestión y la conservación de ecosistemas marinos y costeros: Isla Gorgona, Océano Pacífico Colombiano / Hydrodynamics applied to the management and conservation of marine and coastal ecosystems: Gorgona Island, Colombian Pacific Ocean

Palmeras (Gorgona National Park) is one of the most important sites for sea turtle nesting in South and Central America. Because of the morphological processes affecting the beach, the turtle nests are increasingly exposed to the impact of waves and tides, threatening conservation. A study was made to determine the hydrodynamical processes of the zone adjacent to Playa Palmeras, which affects directly the morphodynamical behavior of the beach and thus the preservation of the nests. Field measurements and numerical modeling were used to obtain the general circulation patterns and thermohaline structure behavior in the area in order to determine the spatial and temporal variability of waves and its effects on the beach. A marked seasonality was found, both in the waves and the currents, influenced mainly by the meridional displacement of the ITCZ (Inter-Tropical Convergence Zone) and an interannual variability of the waves, associated with ENSO (El Niño Southern Oscillation). The flooding levels of the beach were determined and flooding probability maps were made, where safer sites to locate the turtle nests could be identified. These maps serve the officials responsible of monitoring the turtles as a tool to take decisions on moving the nests, since they have flood risk information for any point on the beach. The results show that the middle zone north of the beach is the one with the lowest risk of flooding, therefore the most appropriate zone to relocate nests that are in high risk areas. Rev. Biol. Trop. 62 (Suppl. 1): 133-147. Epub 2014 February 01.

Playa Palmeras (En el Parque Nacional Isla Gorgona) es uno de los sitios más importantes para la anidación de tortugas marinas en América del Sur y Centroamérica. Debido a procesos morfológicos que afectan la playa, los nidos de las tortugas se han visto cada vez más expuestos al impacto del oleaje y la marea, poniendo en riesgo la conservación de éstas especies. Se llevó a cabo un estudio para conocer los procesos hidrodinámicos de la zona costera en Playa Palmeras, de los cuales depende el comportamiento morfodinámico de la playa y la preservación de los nidos. Se usó modelación numérica y mediciones en campo para conocer la variabilidad espacio-temporal del oleaje y obtener los patrones generales de circulación y la estructura termohalina de la zona. Se encontró un marcado ciclo anual, tanto en el oleaje como en las corrientes, influenciado por la Zona de Convergencia Intertropical (ZCIT) y una variabilidad interanual del oleaje, asociada a El Niño Oscilación del Sur (ENSO). Se estimó la cota de inundación de la playa y se crearon mapas de probabilidad de inundación, identificando los sitios potencialmente más seguros para la anidación. Los resultados muestran que hacia el norte de la playa está la zona de menor riesgo.

A diachronic view of the net longshore sediment drift during the Late Holocene at the Jequitinhonha River delta, Brazil, using numerical modeling

Using numerical modeling, this work estimates sediment dispersion patterns caused by the incidence of waves in five distinct coastline contours of the Jequitinhonha River delta plain during the Late Holocene. For this study, a wave cliate odel based on the construction of ave refraction diagras relative to the current boundary conditions as defined and assumed to be valid for the five coastlines. Numerical modeling from the refraction diagrams was carried out considering the angle of incidence and wave height along the coastline. This work has allowed us to reproduce past and current patterns of net longshore sediment drift defined by a conceptual model developed from the integration of sediment cores, aerial photograph interpretation, C14 datings and geomorphic indicators of longshore drift. These results show that, on average, current wave conditions in the east-northeastern Brazilian region seem to have remained characteristically the same from approximately 5100 years BP until the present time. This type of information can be important when attempting to simulate possible future situations in terms of the long-term general behavior of the east-northeastern Brazilian coastal region.

O presente trabalho apresenta uma estimativa, por modelagem numérica, dos padrões de dispersão de sedimentos causados pela incidência de ondas em cinco distintos contornos de linhas de costa da planície deltaica do Rio Jequitinhonha durante o Holoceno Tardio. Para isso, um modelo de clima de ondas baseado na construção de diagramas de refração de onda, em função das condições de contorno atuais, foi definido e assumido ser válido para as cinco linhas de costa. A modelagem numérica, a partir dos diagramas de refração, foi feita considerando o ângulo de aproximação e a altura da onda ao longo da linha de costa. O trabalho permitiu reproduzir os padrões pretéritos e atuais da deriva litorânea efetiva de sedimentos, definidos por um modelo conceitual desenvolvido a partir da integração de testemunhos de sedimentos, interpretação de fotos aéreas e datações de C14, bem como por indicadores geomórficos de deriva. Estes resultados mostram que, em média, em relação à região leste-nordeste brasileira as condições de onda atuais parecem ter permanecido com as mesmas características desde aproximadamente 5.100 anos A.P. até o tempo atual. Esse tipo de informação pode ser importante para tentativas de simulação de possíveis situações futuras em termos do comportamento genérico de longa duração das regiões costeiras leste-nordeste brasileira.

Avaliação dos prognósticos de precipitação simulada pelo modelo BRAMS na Amazônia Ocidental na estação chuvosa / Evaluation of prognostic of rainfall model BRAMS in Western Amazonia during the wet season

O objetivo deste estudo é avaliar o modelo de previsão numérica do tempo BRAMS (Brazilian Regional Atmospheric Modelling System), a partir da comparação entre os valores preditos e os observados (dados do NCEP/NOAA (National Centers of Environmental Predictions/ National Oceanic and Atmospheric Administration) e do satélite TRMM (Tropical Rainfall Measuring Mission)). O modelo foi assimilado com dados do modelo global do NCEP/NOAA e do CPTEC/INPE. Foram realizadas comparações entre os valores preditos e os observados através da raiz do erro quadrático médio (RMSE) e do erro médio (ME) para os prognósticos de precipitação para os horizontes de 24, 48, 72 e 96 horas, do período de novembro de 2008 a março de 2009. Os resultados mostraram que o modelo BRAMS teve uma performance melhor quando assimilado com dados do modelo global do NCEP/NOAA comparado com as saídas a partir das assimilações do modelo global do CPTEC/INPE.

The objective of this study is to evaluate the model of numerical forecast BRAMS (Brazilian Regional Atmospheric Modelling System) from the comparison between the forecast and observed rainfall (data of NCEP/NOAA (National Centers of Environmental Predictions/ National Oceanic and Atmospheric Administration) and of TRMM satellite (Tropical Rainfall Measuring Mission)). The model used the initial conditions of global model of NCEP/NOAA e do CPTEC/INPE. Comparisons between predicted values and observed through were the root medium square error (RMSE) and of medium error (ME) for the forecast of rainfall of 24, 48, 72 and 96 hours, of the period November of 2008 to March of 2009. The results showed that the BRAMS model had better performance when treated with global model data from NCEP / NOAA compared with the outputs from the assimilation of the global model of CPTEC / INPE.

Internal boundary parameters identification of human middle ear with neural network / 医用生物力学

Objective To study the method of internal boundary parameters identification of middle ear.Method The numerical model is created using CT technology.Based on Matlab tools,the neural network for identifying internal boundary is proposed.Result The uniform pressure of 105 dB is applied at the outside of the tympanic membrane,and the harmonic analysis is calculated on the model to take the training samples.The internal condition parameters are identified using the good neural network.Conclusions The investiga-tion shows that the inverse method reveals a fast convergence and a high degree of accuracy.

Internal boundary parameters identification of human middle ear with neural network / 医用生物力学

Objective To study the method of internal boundary parameters identification of middle ear.Method The numerical model is created using CT technology.Based on Matlab tools,the neural network for identifying internal boundary is proposed.Result The uniform pressure of 105 dB is applied at the outside of the tympanic membrane,and the harmonic analysis is calculated on the model to take the training samples.The internal condition parameters are identified using the good neural network.Conclusions The investiga-tion shows that the inverse method reveals a fast convergence and a high degree of accuracy.

Internal boundary parameters identification of human middle ear with neural network / 医用生物力学

Objective To study the method of internal boundary parameters identification of middle ear.Method The numerical model is created using CT technology.Based on Matlab tools,the neural network for identifying internal boundary is proposed.Result The uniform pressure of 105 dB is applied at the outside of the tympanic membrane,and the harmonic analysis is calculated on the model to take the training samples.The internal condition parameters are identified using the good neural network.Conclusions The investiga-tion shows that the inverse method reveals a fast convergence and a high degree of accuracy.