Traffic congestion is usually observed at the upper streams of bottlenecks like tunnels. Congestion appears as stop-and-go waves and high density uniform flow. We perform simulations of traffic flow with a bottleneck using the coupled map optimal velocity model. The bottleneck is expressed as a road segment with speed reduction. The emergence of stop-andgo waves depends on the speed reduction i...

This paper presents Growing Neural Gas (GNG) based a maximum power point tracking (MPPT) technique for a high performance wind generator using DFIG. It is used in variable speed wind energy conversion system. Here, two back to back converters is used and connected to the stator, correspondingly FOC and VOC is done on machine and supply side converter. Constant voltage over the grid is obtained ...

Extracting important statistical patterns from wind speed time series at different time scales is of interest to wind energy industry in terms of wind turbine optimal control, wind energy dispatch/scheduling, wind energy project design and assessment, and so on. In this paper, a systematic way is presented to estimate the first order (one step) Markov chain transition matrix from wind speed tim...

An interesting characteristic of avian gliders is their ability to soar or remain aloft without flapping their wings for long periods. There are two ways to do this. In static soaring a bird maintains or gains altitude by gliding in air that has an upward velocity component equal to or greater than the bird's sinking speed. In dynamic soaring a bird uses changes in the horizontal wind-velocity ...

CFD requires validation for complicated flow problems involving complex physics such as turbulence. Wind tunnels are still the most commonly used validation tools for CFD including physical modelling although some limited use of reliable DNS data base for simple geometries is recently becoming possible. One can observe the trend that a higher and higher demand on the accuracy of the wind tunnel...

in recent years, there has been a fast growth in wind energy conversion system (wecs). there are two general types of wind turbines in wecs: fixed speed wind turbines and varying speed wind turbines.permanent magnet synchronous generator (pmsg) is one of the most attractive generators for the varying speed turbine wecs.in this paper, a fuzzy controller is proposed to control the current source ...

The emphasis on renewable energy and concerns about the environment have led to large-scale wind energy penetration worldwide. However, there are also significant challenges associated with the use of wind energy due to the intermittent and unstable nature of wind. High-quality short-term wind speed forecasting is critical to reliable and secure power system operations. This article begins with...

[1] The aerodynamic friction between air and sea is an important part of the momentum balance in the development of tropical cyclones. Measurements of the drag coefficient, relating the tangential stress (frictional drag) between wind and water to the wind speed and air density, have yielded reliable information in wind speeds less than 20 m/s (about 39 knots). In these moderate conditions it i...

The wind speed forecasting in Hong Kong is more difficult than in other places in the same latitude for two reasons: the great affect from the urbanization of Hong Kong in the long term, and the very high wind speeds brought by the tropical cyclones. Therefore, prediction model with higher learning ability is in need for the wind speed forecast in Hong Kong. In this paper, we try to employ the ...