![]() ![]() Figure 3:Gaussian plume models (calculated using Frankfurt data through online service) Pollen Dispersal from other researchįrom a related study about pollen dispersal the following information has been excerpted (Gail MacInnis, 2012). ![]() The calculation is made by Air Resources Laboratory (ARL) through the online service which we find out the high-density area tend to be around 500 meters from the source. With the Frankfurt wind data, the result of Gaussian plume models is shown in Figure 3. ![]() It is used to calculate pollen dispersal distance of high density pollen area. To determine the Gaussian plume models in the study area (Frankfurt), the average wind speed of 4.725 mph of historical wind data was used. Here, H denotes height of source, ū denotes mean wind speed, and Ws denotes settling velocity - Okubo and Levin (1989) (B) Schematic for the tilted plume model. (Gail MacInnis, 2012) Figure 2: (A): Schematic for Gaussian plume model, viewed from above. Where u* is the frictional velocity, x r is the release height, and k is the von Kármán constant, regularly used for describing the logarithmic velocity profile of a turbulent fluid flow near a boundary layer. V t is the terminal velocity of the grain, ū is the time and depth averaged horizontal wind velocity, σ is the mean eddy diffusivity (for boundary rather than canopy layer flow) and is described as 2Ax 1/ ū, where A is the diffusion coefficient given by k(u*)(x*)/2. Where p(x 1) is the probability density function of locating a seed or pollen grain at a distance, x 1, on the ground with respect to a point source at a given height, x r. Adding release height and gravitational effects (for “heavy” particles) brought about the next generation of Gaussian plume models, is known as the tilted Gaussian plume (Okubo and Levin, 1989): Figure 1: Gaussian plume models This approach deals with light particles with a terminal velocity of zero, and ground level emission. Many researches and studies use this model to apply for pollen grain as well. Gaussian plume models are most commonly used in air-pollution studies, to predict particle concentrations in terms of distance from a ground-level point source. Pollen Dispersal from tilted Gaussian plume models However, there have been a very limited number of studies done to quantify the correlation between distance travelled and horizontal wind velocity, and those who have focused on this topic have come up with varying results. Since the wind is the vector by which the pollen is transported, one would think the most influential parameter would be the horizontal wind velocity (Di Giovanni and Kevan, 1991). It contains a rich set of features for displaying and interacting with geographic data and representing a wide range of geometric objects ().įrom research, it seems that atmospheric parameters such as turbulence, wind velocity and direction play a very important role in determining the dispersal of a pollen grain. Developers can provide custom terrain and imagery. Web World Wind provides high-resolution terrain and imagery, retrieved from remote servers automatically as needed. It provides a geographic context, complete with terrain, for visualizing geographic or geo-located information in 3D and 2D. NASA Web World Wind is a 3D virtual globe API for JavaScript, developed by NASA. Overall, it aims to help people with tree pollen allergies to make the right decision about all their activities, for example to select the right place for living or to plan the route to travel which has low level of pollen dispersion. It analyzes the area of high pollen dispersion dynamically according to the tree location, tree type and wind information by the period of time.Īdditionally, it is possible for users to enter the new tree data which is not yet included in the application database, so users can contribute to update the performance of the application over time. It illustrates the real-time and past behavior of pollen dispersion at a specific location from each tree directly. It facilitates a visualization of trees with the analyzed areas of the pollen dispersion in the city area. “Smart Pollen Monitoring” is a simple and yet powerful 3D-web-based application project designed especially for them. This allergic reaction can cause the following symptoms: itchy watery eyes, runny nose, itchy throat, hives, fatigue, and irritability. Their immune system treats the pollen as an invader and responds by mobilizing to attack, producing large amounts of antibody. For people with allergies, pollen is an allergen that causes an allergic reaction. ![]()
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