An Innovative Workflow for Appropriate Selection of Subsurface-Surface Model Integration Scheme Based on Petroleum Production System Nature, User Needs, and Integrated Simulation Performance

The development of an offshore petroleum production system corresponds to define a set of equipment to make possible oil and gas extraction from an underwater petroleum reservoir. To better comprehension of the process, definition of this production system can be divided into phases. Phase I corresponds to the selection of number of wells and type of the well. Then, following the previous work (Franco, 2003), in the Phase II, the layout arrangement of wells and the set of the stationary Floating Production Unit (FPU) are selected. And, in the Phase III, storage and offloading alternatives for the produced oil and gas are selected. The present paper aims to identify environmental impacts associated with the each component of an offshore system for oil and gas production, and quantify each of them through indexes. It is expected to support the decision makers to select the best fitted system for a given offshore petroleum field. The increasing needs of petroleum to fulfill the energy matrix demanded in Brazil, the growing concern of the society for keeping the environment clean and the inclusion of an index related to the environment besides the technical and technological indexes usually taken makes it an important contribution to improve the process for selection and decision about the offshore production system. Particularly, it will be fundamental in the adverse condition of the Pre-salt scenario of petroleum production, in ultra-deep water depth and oil and gas with more aggressive contaminants to the system. The proposed methodology follows a similar procedure for the assessment of environmental impacts through the use of environmental sensitivity index (ESI) and the use of impact matrix (NOOA, 1997; Patin, 1999; Mariano and La Rovere, 2006). For the estimation of environmental impacts, it was defined the ESI of the area to be developed, and it was constructed an impact matrix based on the activities involved in the installation of platform, operational phase and decommissioning of a FPU and the elements from environment. Therefore, this systematic and structured approach allowed incorporating to the process of selection of the offshore production system for an oil and gas field the selection of alternative which combines the best technical and technological characteristics with better aspects from the environment.

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An Improved Canopy Integration Scheme for a Land Surface Model with Prognostic Canopy Structure

Journal of Climate ◽

10.1175/jcli4222.1 ◽

2007 ◽

Vol 20 (15) ◽

pp. 3902-3923 ◽

Cited By ~ 147

Author(s):

Peter E. Thornton ◽

Niklaus E. Zimmermann

Keyword(s):

Leaf Area ◽

Specific Leaf Area ◽

Land Surface ◽

Temperate Climate ◽

Integration Scheme ◽

Surface Model ◽

Area Index ◽

Climate System Model ◽

Community Land Model ◽

Canopy Model

Abstract A new logical framework relating the structural and functional characteristics of a vegetation canopy is presented, based on the hypothesis that the ratio of leaf area to leaf mass (specific leaf area) varies linearly with overlying leaf area index within the canopy. Measurements of vertical gradients in specific leaf area and leaf carbon:nitrogen ratio for five species (two deciduous and three evergreen) in a temperate climate support this hypothesis. This new logic is combined with a two-leaf (sunlit and shaded) canopy model to arrive at a new canopy integration scheme for use in the land surface component of a climate system model. An inconsistency in the released model radiation code is identified and corrected. Also introduced here is a prognostic canopy model with coupled carbon and nitrogen cycle dynamics. The new scheme is implemented within the Community Land Model and tested in both diagnostic and prognostic canopy modes. The new scheme increases global gross primary production by 66% (from 65 to 108 Pg carbon yr−1) for diagnostic model simulations driven with reanalysis surface weather, with similar results (117 PgC yr−1) for the new prognostic model. Comparison of model predictions to global syntheses of observations shows generally good agreement for net primary productivity (NPP) across a range of vegetation types, with likely underestimation of NPP in tundra and larch communities. Vegetation carbon stocks are higher than observed in forest systems, but the ranking of stocks by vegetation type is accurately captured.

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Численные подходы к решению нелинейной системы уравнений Шрёдингера для распространения волн в оптическом волокне

Вычислительные технологии ◽

10.25743/ict.2020.25.2.007 ◽

2020 ◽

Author(s):

A.J. Sakhabutdinov ◽

V.I. Anfinogentov ◽

O.G. Morozov ◽

R.R. Gubaidullin

Keyword(s):

Finite Difference ◽

Nonlinear Term ◽

Initial Boundary ◽

Equation System ◽

Integration Scheme ◽

Integration Step ◽

Disturbance Propagation ◽

Calculation Results ◽

Definition Of ◽

Selection Of

The paper discusses approaches to the numerical integration of the second-kind Manakov equation system. Emphasis is placed on the transition from writing equations in dimensional quantities to equations in dimensionless units. A combined explicit/implicit finite-difference integration scheme based on the implicit CrankNicolson finite-difference scheme is proposed and substantiated, which allows integrating a nonlinear system of equations with a choice of nonlinear term at the previous integration step. An algorithm for leveling the disadvantage associated with the definition of the nonlinear term from the previous integration step is proposed. The approach of automatic selection of the integration step, which reduces the total number of integration steps while maintaining the required accuracy of the approximate solution, is substantiated. Examples of the calculation results for some values of the disturbance propagation are given. The limitations imposed by the computing scheme on the length of the integrable fiber section are described, and approaches, that eliminate these limitations without the need to increase arrays dimensions, are proposed. Requirements for initial boundary conditions are discussed. Предложена разработка метода приближенного решения системы уравнения Манакова как одного из частных случаев системы уравнений Шрёдингера, связанного с моделированием оптических линий связи на основе многомодовых волокон. Решение ищется методами численного интегрирования. Показано, что численное интегрирование может быть осуществлено с использованием комбинированной явно-неявной схемы численного интегрирования на основе схемы КранкаНиколсон с записью нелинейного слагаемого в конечно-разностной форме, взятого с предыдущего шага интегрирования. Использован алгоритм автоматического выбора шага интегрирования, реализован итерационный алгоритм уточнения решения на каждом шаге, предложен алгоритм, позволяющий производить расчет параметров на протяженных участках. Нахождение приближенного решения системы уравнения Манакова может быть осуществлено с использованием комбинированной явно-неявной схемы КранкаНиколсон, а запись нелинейного слагаемого в конечно-разностной форме, взятого с предыдущего шага интегрирования, дает неплохой результат. Алгоритм автоматического выбора шага интегрирования обеспечивает лучшую сходимость результатов интегрирования на большом расстоянии и снижение необходимого количества шагов интегрирования. Алгоритм уточнения решения на каждом шаге позволяет нивелировать недостаток метода явной записи неявного слагаемого и интегрировать с большим шагом. Алгоритм расчета параметров распространения возмущения со сдвигом фрейма позволяет сделать вывод о целесообразности развития этого алгоритма.

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Interaction Between Camel Farming and Environment

Handbook of Research on Health and Environmental Benefits of Camel Products - Practice, Progress, and Proficiency in Sustainability ◽

10.4018/978-1-7998-1604-1.ch017 ◽

2020 ◽

pp. 363-378

Author(s):

Bernard Faye

Keyword(s):

Production System ◽

Greenhouse Gas Emission ◽

Desert Environment ◽

Active Growth ◽

Current Trends ◽

The World ◽

Animal Metabolism ◽

Extensive Farming ◽

The Impact ◽

Selection Of

The close adaptation of camel to its desert environment could explain its weak expansion out of the arid lands of the world. This adaptation can contribute to the desertification combat, attesting to its small ecological footprint with traditional extensive farming. The camel population in the world, despite its active growth, remains marginal, and its contribution to the greenhouse gas emission is negligible. However, the current trends to the intensification of camel productions could change the impact of the species on the environment and on animal metabolism. The necessity to expect a better productivity face to the growing demand could lead to a “specialization” of the camel farms and a specific selection of the camel. Such trends require care with a possible erosion of the camel biodiversity and the consequences on the interactions between the emerging camel production system and the environment.

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Selection of Materials for Sour Service in Petroleum Production

Journal of Petroleum Technology ◽

10.2118/16040-pa ◽

1986 ◽

Vol 38 (10) ◽

pp. 1051-1061 ◽

Cited By ~ 6

Author(s):

S. Mark Wilhelm ◽

Russell D. Kane

Keyword(s):

Petroleum Production ◽

Sour Service ◽

Selection Of

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Satellite imagery technology in public health: analysis of site catchment areas for assessment of poliovirus circulation in Nigeria and Niger

Geospatial health ◽

10.4081/gh.2016.462 ◽

2016 ◽

Vol 11 (3) ◽

Author(s):

Marina Takane ◽

Shizu Yabe ◽

Yumiko Tateshita ◽

Yusuke Kobayashi ◽

Akihiko Hino ◽

...

Keyword(s):

Population Size ◽

Population Data ◽

Sewage Water ◽

Small Scale ◽

Surface Model ◽

Environmental Surveillance ◽

Outbreak Response ◽

Catchment Areas ◽

Elevation Model ◽

Selection Of

Environmental surveillance supplements the surveillance of acute flaccid paralysis by monitoring wastewater for poliovirus circulation. Building on previous work, we analysed wastewater flow to optimise selection and placement of sampling sites with higher digital surface model (DSM) resolution. The newly developed 5-m mesh DSM from the panchromatic, remote-sensing instruments for stereo mapping on-board the Japanese advanced land observing satellite was used to estimate catchment areas and flow of sewage water based on terrain topography. Optimal sampling sites for environmental surveillance were identified to maximise sensitivity to poliovirus circulation. Population data were overlaid to prioritise selection of catchment areas with dense populations. The results for Kano City, Nigeria were compared with an analysis based on existing 30- and 90-m mesh digital elevation model (DEM). Analysis based on 5-m mesh DSM was also conducted for three cities in Niger to prioritise the selection of new sites. The analysis demonstrated the feasibility of using DSMs to estimate catchment areas and population size for programme planning and outbreak response with respect to polio. Alternative sampling points in Kano City that would cover a greater population size have been identified and potential sampling sites in Niger are proposed. Comparison with lower-resolution DEMs suggests that the use of a 5-m mesh DSMs would be useful where the terrain is flat or includes small-scale topographic changes not captured by 30-m data searches.

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