Energy consumption in industrial facilities has accounted for more than half of the total national fuel consumption. The average concentration of the measured data was 24. Gridded terrain data are used to calculate a representative terrain-influenced height hc , associated with each receptor location, and to calculate the dividing streamline height. Two years of monitored data from 10 receptor sites in the study area were used for intensive evaluations of model performances. The model predicts the transport, dispersion, chemical reactions, optical effects and surface deposition of point or area source emissions. The guidance goes on to recommend the fractional bias as a screening tool for evaluating whether a model should be eliminated from consideration. The elements of the beta-test version that has previously been available are implemented into the new release.
The dispersion module uses a Lagrangian puff formulation, along with a gridded non-uniform wind and stability field derived from traffic module outputs, to describe near-roadway dispersion characteristics. The traffic module is a microscale transportation model which simulates individual vehicle movement. All other code changes enhancements and new features are not included at this time. These profiles are represented by equivalent values constructed by averaging these values over the planetary boundary layer through which the plume material travels directly from the source to the receptor. In the afternoon additional case study problems will be solved.
You may also register to receive notices of model updates. Meteorological data contained hourly wind speeds, temperature, cloud covers, ceiling heights, surface pressures, and relative humidity. Nitrogen Oxides in Combustion Processes. The quantile—quantile Q—Q plots for each model and field study are developed from the ranked and paired distributions of observations and predictions. This update includes code changes described in Model Change Bulletin B , and.
Learn more about this journal. The mean bias is easily understood and preserved the sign of bias. In Thailand, a large number of power plants and industrial facilities are present and the industrial growth continues. All editorial decisions made by independent academic editor. More information on the specific model updates are provided in the download area of the web page.
Performance Evaluation Numerous steps have been taken to ensure that the best model is properly used for each regulatory application and that the model is not arbitrarily imposed. The model was simulated covering the years 2012 and 2013. Performance measures included the fractional bias, normalized mean square error, geometric mean, geometric mean variance, correlation coefficient, and fraction of observations within a factor of two. These changes are based on work by Karamchandani et al. More recently ownership transferred to E xponent, who are currently December 2015 responsible for maintaining and distributing the model. Measures of correlation indicate quantitative measures of the association between predicted and observed values. The Sigma Research Corporation subsequently became part of Earth Tech, Inc.
Limitations: Limitations It only approximates atmospheric processes. It is maintained by the model developers and distributed by Exponent. Prior to publication all authors have given signed confirmation of agreement to article publication and compliance with all applicable ethical and legal requirements, including the accuracy of author and contributor information, disclosure of competing interests and funding sources, compliance with ethical requirements relating to human and animal study participants, and compliance with any copyright requirements of third parties. As for quality control of data, all the analyzer from every stations were daily calibrated by standard gas following the guideline of the ambient air-monitoring station designated by the Pollution Control Department of Thailand. Our scientists and engineers have been influential in the evolution of air quality modeling and have developed or contributed to multiple models used regularly for Air Quality assessments throughout the world. The model also includes algorithm for handling the effect of downwash by nearby buildings in the path of the pollution plumes. The 2005 results are available on the.
Modeled results were compared with those measured data from 10 receptor sites. All authors reviewed and approved the final manuscript. There were differences between the model and observed values. The Acid Deposition Control Strategy in the Kingdom of Thailand. It includes algorithms for near-field effects such as stack tip downwash, building downwash, transitional buoyant and momentum plume rise, rain cap effects, partial plume penetration, subgrid scale terrain and coastal interactions effects, and terrain impingement as well as longer range effects such as pollutant removal due to wet scavenging and dry deposition, chemical transformation, vertical wind shear effects, overwater transport, plume fumigation, and visibility effects of particulate matter concentrations. Input data needed are emissions data, meteorological data and census tract data. Model Configuration Air pollutant concentrations were calculated in one-hour period on elevated terrain height and urban area option.
Version 6 of the model has been updated to include all updates through as well as the new regulatory switch used in Version 5. Bangkok: Pollution Control Department; 2003. In addition, several bugs were identified and fixed with v6. The model also includes for handling the effect of downwash by nearby buildings in the path of the pollution plumes. The model includes algorithms which take account of the following: effects of main site buiding; complex terrrain; wet deposition, gravitational settling and dry deposition; short term fluctuations in concentration; chemical reactions; radioactive decay and gamma-dose; plume rise as a function of distance; jets and directional releases; averaging time ranging from very short to annual; condensed plume visibility; meteorological preprocessor.
Performance objectives were unpaired maximum one- and nine-hour average concentration, location of plume maximum, plume impact area, arc-integrated concentration, unpaired nine-hour average concentration, and paired ensemble means. In addition, it produces mixing height, surface characteristics, and dispersion properties. Air pollution is an important issue to which people have paid considerable attention. Model Code and Documentation 13. Air pollution can pose risks to both public health and welfare.
Data periods read from meteorological data files started from the first hour in January 1, 2012, to the 24th hour in December 31, 2013. In addition a bug was fixed to correctly address missing data in wind rose calculations. Proximity analysis of air pollution exposure and its potential risk. The applicability of a model in general depends on many reasons, but the accuracy of a model is one of normally determined by an evaluation procedure that involves the comparisons of the modeled concentrations with measured air quality data. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 3.