Model simulation

In this paper, a lumped parameter model of electromechanical systems is developed and its solution is simplified by using look-up tables (LT). The model is developed in two steps. First, a Simulink model of the electromechanical system is built using algebraic equations of the magnetic circuit which contains nonlinear effects. In the second step, the model is simplified using LT

The Okubo pond is an agricultural pond located in the Itoshima area of Fukuoka Prefecture, Japan. It was constructed for irrigating a nearby cultivated area. A monitoring program from August 11 to November 26, 2008, suggested the risk of eutrophication in the water body. The high total nitrogen concentration (1.34 mg/l), high total phosphorus concentration (0.06 mg/l) and extreme oxygen

The simulation of commodity prices has been undertaken using a myriad of techniques, with some omitting the cyclical component and others ignoring the presence of inter-temporal relationships expressed as autoregressive errors. This study examines the periodicity of cattle prices and the modeling of the cattle cycle for simulation purposes. The AIC criterion is used to determine lengths of various cycles to be included in a harmonic model, with a chained modeling approach providing the best representation of the cattle cycle.

ABSTRACT In this paper, we present a study on modeling and control of active and reactive power of a double-fed induction generator (DFIG). We consider the operation of the machine in all areas of operation possible. According to the conditions imposed on references of power we will analyze the performance of the order for different operating modes. Mainly we consider a working with variable wind. The test simulations are performed using Matlab Simulink and the results are presented and analyzed.

Research on the Egyptian food security, has become the subject of countless studies and debates. The gap between the Egyptian domestic food production and consumption is translated into high import costs. In this paper, modeling, simulation analytical capability, expert experiences and imagination, and policy/decision makers' insights are integrated in a decision support system (DSS). The developed DSS is used to anticipate the future of the national food security and to create a consensus about the ...

The impact of volcanic eruptions on the marine carbon cycle is investigated for the example of the Pinatubo eruption with model simulations of the distribution of the ash cloud and deposition on the ocean surface and the impact of the nutrient addition from ash leachates on the oceanic biological production and hence biological carbon pump. Natural variations of aerosols, especially due to large-magnitude volcanic eruptions, are recognized as a significant climate forcing, altering the Earth's radiation balance and thus tending to cause global temperature changes. While the impact of such events on climate and the terrestrial biosphere is relatively well documented, scientific knowledge of their effects on marine ecosystems and consequent feedbacks to the atmosphere is still very limited. In the deep sea, subaerial eruptive events of global significance are commonly recorded as widespread ash layers, which were often found to be associated with increased abundances of planktic ...

Pesticide uses in rice cultivation take generally place during the ponded period. Their persistence in paddy field is the origin of pollution risk according two main ways: (i) directly in the runoff, (ii) moving and leachate in soil. To forecast pesticide behavior and hydraulic pathways in paddy field appear crucial in order to define non point pollution adapted management and

We investigate the non-radiative decay in the photo-isomerization of the dideuterated methaniminium cation HDN+CDH by means of quantum dynamical simulations of the laser driven torsion. For the present model, the torsional dynamics is nearly adiabatic, but this is shown to be extremely sensitive to the large non-adiabatic coupling elements close to the conical intersection as well as to the apparently

In this paper, the electric field distribution obtained from solving Maxwell's equations was coupled to the energy equation to predict the temperature distribution during microwave heating of solids. The effect of sample rotation was incorporated to the model. Simulation runs showed that rotation of the sample results in a more uniform temperature distribution. In small samples, heating was more pronounced