Nopparat Pochai

King Mongkut's Institute of Technology Ladkrabang · Department of Mathematics

A vast number of patients visit the facility every day, causing a major air pollution issue that may pose a risk of exposure of respiratory infectious diseases in outpatient rooms and harm human health. TB, COVID-19, MERS, and SARS are dangerous communicable diseases that transmit from person to person through the air or aerosol in a variety of for...

Beach erosion is a natural phenomenon that is not compensated by depositing fresh material on the shoreline while transporting sand away from the shoreline. There are three phenomena that have a serious influence on the coastal structure, such as increases in flooding, accretion, and water levels. In addition, the prediction of coastal evolution is...

Every day, a large number of people will use a hospital, creating a main air quality problem which may mean the risk of airborne infectious disease contamination in outpatient rooms, and affects human health. TB, COVID-19, MERS, and SARS are a hazardous communicable disease which are spread from person to person through the air or the aerosol in di...

Landfill is a cause of environmental groundwater pollutant. Landfill operations most feasible in many medium income developing countries. The groundwater pollutant measurement is required to control the drinking water quality. The mathematical model are introduced to predict the environmental impact assessment. The predicted impact of groundwater q...

Mathematical models are required for long-term groundwater quality assessment around landfill sites. The long-term groundwater-quality prediction is used to report the environmental impact assessment of landfill site projects. In this research, a one- dimensional transient advection-diffusion equation is used to describe groundwater pollutant conce...

This study aims to develop numerical simulation of one-dimensional advection- diffusion equation. We propose two different methods for salinity intrusion measurement in a stream. In the first method, the forward time centered space (FTCS) is used. In the second method, the MacCormack scheme is applied. The results from these methods can be used as...

Nutrient pollution negatively affects ecology, environment and human health, due to excess contaminated nitrogen in aquatic ecosystems. Nitrogen has various forms, such as organic nitrogen, ammonia, nitrite, and nitrate. Nitrogen removal mechanisms are important for nitrogen compound pollutant control. Microbial agents provide an alternative for ni...

Abstract Salinity refers to the amount of salt in rivers, where the salt can be in many different forms. There are two main methods of defining the concentration of salt in water such as the total dissolved solid measurement (TDS) and the electrical conductivity measurement (EC). The salinity is measured by evaporating water to dryness and weighing...

A numerical simulation on a two-dimensional atmospheric diffusion equation of an air pollution measurement model is proposed. The considered area is separated into two parts that are an industrial zone and an urban zone. In this research, the air pollution measurement by releasing the pollutant from multiple point sources above an industrial zone t...

This article deals with the analytical study of MHD flow and heat transfer over a permeable stretching sheet via homotopy analysis method (HAM). The effect of thermal radiation is included in the energy equation, while velocity and thermal slips are included in the boundary conditions. The governing boundary layer equations are transformed into a s...

Air pollutant levels in Bangkok are generally high in street tunnels. They are particularly elevated in almost closed street tunnels such as an area the Bangkok sky train platform with high traffic volume where dispersion is limited. This area has no air quality measurement stations even though there is a high percentage of people living around thi...

Air pollutant levels in Bangkok are generally high in street tunnels. They are particularly elevated in almost closed street tunnels such as an area under the Bangkok sky train platform with high traffic volume where dispersion is limited. There are no air quality measurement stations in the vicinity, while the human population is high. In this res...

The one-dimensional advection-diffusion-reaction equation is a mathematical model describing transport and diffusion problems such as pollutants and suspended matter in a stream or canal. If the pollutant concentration at the discharge point is not uniform, then numerical methods and data analysis techniques were introduced. In this research, a num...

One of the air pollution problems in areas under Bangkok sky train platforms are caused by the pollutant coming from the entrance to the tunnel. It increases the concentration of pollutant. This affects the well-being of humans and the environment. In this research, the governing equation of the air quality model in a considered area is a three-dim...

One of the air pollution problems in areas under Bangkok sky train platforms are caused by the pollutant coming from the entrance to the tunnel. It increases the concentration of pollutant. This affects the well-being of humans and the environment. In this research, the governing equation of the air quality model in a considered area is a three-dim...

A rapid industrial development causes several environment pollution problems. One of the main problems is air pollution, which affects human health and the environment. The consideration of an air pollutant has to focus on a polluted source. An industrial factory is an important reason that releases the air pollutant into the atmosphere. Thus a mat...

Two mathematical models are used to simulate water quality in a non-uniform flow stream. The first model is the hydrodynamic model that provides the velocity field and the water elevation. The second model is an advection-diffusion-reaction model that provides the pollutant concentration field. Both models are formulated as one-dimensional equation...

The groundwater measurement is obliged to take care of the issue of need water assets in numerous dry season ranges for agricultural use. In this study, we propose a groundwater stream model demonstrate that gives the pumping rates and the infusion rates individually. The objective are to propose a simply and flexible groundwater simulation using t...

The heavy monsoon rains have been drenched flooding along the rivers and reservoirs. The residents try to construct the sandbag dike to protect their village. If the residents have encountered flood for long period, the water pollutant must be increase. The villagers want to drain the water to another areas. The residents of another village are not...

A numerical treatment for axisymmetric flow and heat transfer due to a stretching cylinder under the influence of a uniform magnetic field and prescribed surface heat flux is presented. Numerical results are obtained for dimensionless velocity, temperature, skin friction coefficient and Nusselt number for several values of the suction/injection, ma...

The air pollutants emitted from industrial plants are considered one of the major causes of the typical air pollution problem. A mathematical model for describing the dispersion of the air pollutants released from the source into the atmosphere is examined. A numerical approximation using the three dimensional fractional step method is applied base...

In this paper, two mathematical models for simulating water pollutant level and pollution control in a connected reservoir system are proposed. The reservoir system is consisted of two ponds connected by a narrow channel. One pond allows water in from a canal through an entrance gate while the other pond lets the water flow out through an exit gate...

A theoretical investigation is carried out to examine the effects of volume fraction of nanoparticles, suction/injection, and convective heat and mass transfer parameters on MHD stagnation point flow of water-based nanofluids (Cu and Ag). The governing partial differential equations for the fluid flow, temperature, and concentration are reduced to...

We investigated the magnetohydrodynamic (MHD) boundary layer flow over a nonlinear porous stretching sheet with the help of semianalytical method known as optimal homotopy asymptotic method (OHAM). The effects of different parameters on fluid flow are investigated and discussed. The obtained results are compared with numerical Runge-Kutta-Fehlberg...

Measuring the water quality in water sources or the Monkey Cheeks Project with opened-closed reservoir. It can be measured by the field measurement, using the water quality monitoring tools and the water quality models consist of hydrodynamic model and dispersion model, to calculate the quality of the water. Hydrodynamic model, using the shallow wa...

The heat flow patterns profiles are required for heat transfer simulation in each type of the thermal insulation. The exothermic reaction models in porous medium can prescribe the problems in the form of nonlinear ordinary differential equations. In this research, the driving force model due to the temperature gradients is considered. A governing e...

We have investigated a thin film flow of a third grade fluid on a moving belt using a powerful and relatively new approximate analytical technique known as optimal homotopy asymptotic method (OHAM). The variation of velocity profile for different parameters is compared with the numerical values obtained by Runge-Kutta Fehlberg fourth-fifth order me...

The purposes of this research are to develop mathematical models and numerical methods for approximating water flow directions and pollution levels in a Rama-nine reservoir, Pathumthani, Thailand with non-uniform current. The Rama-nine reservoir is opened with two parallel canals. The pollution levels in a reservoir are assessing via data collectio...

Two mathematical models are used to simulate water quality in a nonuniform flow stream. The first model is the hydrodynamic model that provides the velocity field and the elevation of water. The second model is the dispersion model that provides the pollutant concentration field. Both models are formulated in one-dimensional equations. The traditio...

We employ approximate analytical method, namely, Optimal Homotopy Asymptotic Method (OHAM), to investigate a one-dimensional steady advection-diffusion-reaction equation with variable inputs arises in the mathematical modeling of dispersion of pollutants in water is proposed. Numerical values are obtained via Runge-Kutta-Fehlberg fourth-fifth order...

The high level salinity in soil is a main problem of a plant grows less in rice field near marine shrimp aquaculture farm. The salinity in soil and ground water flow are required for soil quality assessments. The modeling often involves numerical methods to solve the equations. In this research, two mathematical models are used to simulate the sali...

The source of air pollutant is the main of conducting emission in-ventories. The smoke discharging from industrial plant is a principle reason of air pollution problem. In this research, the comparison of dif-ference numbers of chimney as the same emission rate of the pollutant is considered. The fractional step method is used for solving the smoke...

Water pollution assessment problems arise frequently in environmental science. In this research, a finite difference method for solving a one-dimensional steady convection-diffusion equation with variable coefficients is presented.

A mathematical model is used to simulate the water current and the elevation in a uniform reservoir. A hydrodynamic model that provides the velocity field and elevation of the water flow is considered. In the simulating process, the Lax-Wendroff technique is used to approximate the solutions.

Water pollution assessment problems arise frequently in environmental science. In this research, a finite difference method for solving the one-dimensional steady convection-diffusion equation with variable coefficients is proposed; it is then used to optimize water treatment costs.

The stream water quality model of water quality assessment problems often involves numerical methods to solve the equations. The governing equation of the uniform flow model is one-dimensional advection-dispersion-reaction equations (ADREs). In this paper, a better finite difference scheme for solving ADRE is focused, and the effect of nonuniform w...

The high level salinity of soil is a main problem of a plant grows less in rice field near marine shrimp aquaculture farm. The electrical conductivity of soil is an indicator of soil salinity assessment. The methods to detect the amount of salinity of soil are field measurement and mathematical simulation. In this paper, the direct current model of...

Problem statement: The area under Phayathai station platform of sky train in Bangkok, Thailand, has a problem of air pollution control. Approach: The Bangkok Mass Transit System Company tries to set up the electric fans inside the area for air flow improvement. Results: The flow of the air is still not smooth and the air quality is still lower than...

Mathematical models of water quality assessment problems often arise in environmental science. The modelling often involves numerical methods to solve the equations. In this research, two mathematical models are used to simulate pollution due to sewage effluent in the nonuniform flow of water in a stream with varied current velocity. The first is a...

A mathematical model is used to simulate the water current and the elevation in a uniform reservoir. A non-linear hydrodynamic model that provides the velocity field and elevation of the water flow is considered. In the simulating process, the Lax-Wendroff technique is used to approximate the solutions. The numerical solution can be the input data...

In this research, a mathematical model is used to simulate the pollution in the reservoir. The hydrodynamic model that provides the velocity field and elevation of the water. The dispersion model gives the pollutant concentration as a water quality measurement. The reservoir is connected to the outer water area is considered. In the simulating proc...

Water pollution assessment problems arise frequently in environ-mental science. The hydrodynamic model is used to simulated current in the reservoir that provides the velocity and height of the water. In this research, the numerical computation of velocity and water eleva-tion in two-dimensional non-linear hydrodynamic model is considered. The simu...

In this research, two mathematical models are used to simulate pollution due to sewage effluent in the uniform reservoir with varied current velocity. The first is the hydrodynamic model that provides the velocity field and elevation of the water flow. The second is the dispersion model that gives the pollutant concentration fields. In the simulati...

The numerical solution of water pollutant transport problems arises in many important applications in environmental sciences. In this research, the finite element method for solving the one-dimensional and two-dimensional steady state convection-diffusion equation with constant coefficients of nearly closed water area is presented. The presented ma...

The flow patterns and concentration profiles are needed for fluid be-havior simulation in the underground. The exothermic reaction models in porous medium can be described that requirement. The model is focused on the driving force problem which due to the temperature and concentration gradients at the system boundaries. In this research, the numer...