mahfuz ullah | Bangladesh Army International University of Science & Technology (original) (raw)
Papers by mahfuz ullah
2022 3rd International Conference for Emerging Technology (INCET)
2022 2nd International Conference on Intelligent Technologies (CONIT)
IEEE Canadian Journal of Electrical and Computer Engineering, 2021
Wireless communication networks of desert-belt nations can be severely compromised by frequent du... more Wireless communication networks of desert-belt nations can be severely compromised by frequent dust/sand (DUSA) storms. Existing attenuation and scattering models for electromagnetic (EM) waves often consider homogeneous DUSA media. This article proposes an analytical model of a layer-based DUSA storm to monitor the EM attenuation from different DUSA layers. A lab-based experimental setup is used to measure the attenuation from a specific DUSA layer. The measured results are used to validate an equivalent professional simulator [high-frequency structure simulator (HFSS)] model of the DUSA layer. The agreement between the proposed analytical and simulated results demonstrates the redundancy of complicated experimental validation process. The simulation model also allowed the monitoring of EM attenuation due to different particle sizes, shapes, and concentrations in different homogeneous layers of the DUSA storm. The predicted EM attenuations agreed well with the data available in the...
2020 International Conference for Emerging Technology (INCET), 2020
Wireless Local Area Networks (WLAN) setups are used to cater the need of instant access of mobile... more Wireless Local Area Networks (WLAN) setups are used to cater the need of instant access of mobile internet connection. For an indoor environment, the 802.11 standard lets building such setups pretty easy and convenient. For efficient performance of these setups, optimal positioning of the Access Point (AP) is of utmost importance to serve all the nodes within the network. Profiling of path loss or received power strength can play a vital role in choosing the most suitable position for the AP. This paper tries to bring in an innovative simulation model which enables a user to do that .Here one of the prevalent indoor signal propagation models is used for the modeling purpose. The indoor conditions were taken from real life environments and the simulation was performed to give a comparative idea of the path loss for Indoor environments.
2020 International Conference for Emerging Technology (INCET), 2020
High Voltage Direct Current (HVDC) is a technology associated with power electronics based on sem... more High Voltage Direct Current (HVDC) is a technology associated with power electronics based on semiconductor devices which can be very useful and cost efficient compared to HVAC for long distance transmission. In this paper, a simple 12 pulse HVDC transmission system model has been developed which consists of converter and filter to improve the stability of power transmission. This paper presents the simulation result of a 12 pulse HVDC model to analyze the power, voltage and current profile with a synchronous machine as a generator. It has been found that the rectifier faces some trouble to convert the whole amount of power generated by the machine from AC to DC at a time and the system becomes unstable. A method has been studied to eliminate this phenomenon and to sustain stability to provide a steady state power supply to the rectifier. That was done by connecting several loads parallel with the synchronous machine to consume the excess power and the simulation profile of power, v...
2018 International Applied Computational Electromagnetics Society Symposium (ACES), 2018
During a severe sand storm, maintaining the link budget of wireless channels require accurate mod... more During a severe sand storm, maintaining the link budget of wireless channels require accurate modeling of EM scattering. Existing models used to predict the electromagnetic (EM) attenuation due to dust/sand particles are mostly based on visibility measurement. Since visibility is not constant throughout the sand storm, the attenuation models need a correction factor to include horizontal and vertical intensity variation of the dust/sand particles. This paper presents a simulation model, where EM attenuation due to different size and concentration of the dust/sand particles can be separately investigated. Simulated results are verified with controlled laboratory based experiments and existing data from well known references.
Energy
Abstract Industrial energy efficiency is acknowledged as a cost-effective mean contributing to su... more Abstract Industrial energy efficiency is acknowledged as a cost-effective mean contributing to sustainable development and industrial competitiveness. Implementing energy management practices becomes even more imperative for developing countries, considering their energy usage trends and economic development forecasts. Based on the circumstances, an empirical investigation is conducted on energy efficiency and management practices, as well as barriers and drivers to energy efficiency in the energy-intensive industries of Bangladesh. The study finds that majority of the companies barely implement the energy management practices. Energy audits represent the mostly implemented energy management practice at the industries, though a comprehensive approach on a detailed level is still lacking. In addition, this study finds that the number of dedicated and specialised energy professionals employed in the industries is yet negligible. The cumulated results show that energy efficiency is mostly disrupted due to inadequate support from preeminent administration and bureaucratic intricacy. Energy blueprint cost-saving due to less use of energy and rules and regulations were distinctively signified as most imperative drivers for energy efficiency. On the other hand, lack of information is found to be the most significant barrier to consult energy service companies. Analysis of the country's energy usage and supply-demand relationship points towards insufficient energy efficiency measures and energy management practices in the country. The study also finds that energy efficiency could be improved by 8%–10% through the practice of energy management. Our findings, besides pointing out specific issues to be tackled in the specific context of investigation, pave the way for further research over industrial energy efficiency in developing countries.
Energies
Bangladesh faced a substantial growth in primary energy demand in the last few years. According t... more Bangladesh faced a substantial growth in primary energy demand in the last few years. According to several studies, energy generation is not the only means to address energy demand; efficient energy management practices are also very critical. A pertinent contribution in the energy management at the industrial sector ensures the proper utilization of energy. Energy management and its efficiency in the textile industries of Bangladesh are studied in this paper. The outcomes demonstrate several barriers to energy management practices which are inadequate technical cost-effective measures, inadequate capital expenditure, and poor research and development. However, this study also demonstrates that the risk of high energy prices in the future, assistance from energy professionals, and an energy management scheme constitute the important drivers for the implementation of energy efficiency measures in the studied textile mills. The studied textile industries seem unaccustomed to the dedic...
2022 3rd International Conference for Emerging Technology (INCET)
2022 2nd International Conference on Intelligent Technologies (CONIT)
IEEE Canadian Journal of Electrical and Computer Engineering, 2021
Wireless communication networks of desert-belt nations can be severely compromised by frequent du... more Wireless communication networks of desert-belt nations can be severely compromised by frequent dust/sand (DUSA) storms. Existing attenuation and scattering models for electromagnetic (EM) waves often consider homogeneous DUSA media. This article proposes an analytical model of a layer-based DUSA storm to monitor the EM attenuation from different DUSA layers. A lab-based experimental setup is used to measure the attenuation from a specific DUSA layer. The measured results are used to validate an equivalent professional simulator [high-frequency structure simulator (HFSS)] model of the DUSA layer. The agreement between the proposed analytical and simulated results demonstrates the redundancy of complicated experimental validation process. The simulation model also allowed the monitoring of EM attenuation due to different particle sizes, shapes, and concentrations in different homogeneous layers of the DUSA storm. The predicted EM attenuations agreed well with the data available in the...
2020 International Conference for Emerging Technology (INCET), 2020
Wireless Local Area Networks (WLAN) setups are used to cater the need of instant access of mobile... more Wireless Local Area Networks (WLAN) setups are used to cater the need of instant access of mobile internet connection. For an indoor environment, the 802.11 standard lets building such setups pretty easy and convenient. For efficient performance of these setups, optimal positioning of the Access Point (AP) is of utmost importance to serve all the nodes within the network. Profiling of path loss or received power strength can play a vital role in choosing the most suitable position for the AP. This paper tries to bring in an innovative simulation model which enables a user to do that .Here one of the prevalent indoor signal propagation models is used for the modeling purpose. The indoor conditions were taken from real life environments and the simulation was performed to give a comparative idea of the path loss for Indoor environments.
2020 International Conference for Emerging Technology (INCET), 2020
High Voltage Direct Current (HVDC) is a technology associated with power electronics based on sem... more High Voltage Direct Current (HVDC) is a technology associated with power electronics based on semiconductor devices which can be very useful and cost efficient compared to HVAC for long distance transmission. In this paper, a simple 12 pulse HVDC transmission system model has been developed which consists of converter and filter to improve the stability of power transmission. This paper presents the simulation result of a 12 pulse HVDC model to analyze the power, voltage and current profile with a synchronous machine as a generator. It has been found that the rectifier faces some trouble to convert the whole amount of power generated by the machine from AC to DC at a time and the system becomes unstable. A method has been studied to eliminate this phenomenon and to sustain stability to provide a steady state power supply to the rectifier. That was done by connecting several loads parallel with the synchronous machine to consume the excess power and the simulation profile of power, v...
2018 International Applied Computational Electromagnetics Society Symposium (ACES), 2018
During a severe sand storm, maintaining the link budget of wireless channels require accurate mod... more During a severe sand storm, maintaining the link budget of wireless channels require accurate modeling of EM scattering. Existing models used to predict the electromagnetic (EM) attenuation due to dust/sand particles are mostly based on visibility measurement. Since visibility is not constant throughout the sand storm, the attenuation models need a correction factor to include horizontal and vertical intensity variation of the dust/sand particles. This paper presents a simulation model, where EM attenuation due to different size and concentration of the dust/sand particles can be separately investigated. Simulated results are verified with controlled laboratory based experiments and existing data from well known references.
Energy
Abstract Industrial energy efficiency is acknowledged as a cost-effective mean contributing to su... more Abstract Industrial energy efficiency is acknowledged as a cost-effective mean contributing to sustainable development and industrial competitiveness. Implementing energy management practices becomes even more imperative for developing countries, considering their energy usage trends and economic development forecasts. Based on the circumstances, an empirical investigation is conducted on energy efficiency and management practices, as well as barriers and drivers to energy efficiency in the energy-intensive industries of Bangladesh. The study finds that majority of the companies barely implement the energy management practices. Energy audits represent the mostly implemented energy management practice at the industries, though a comprehensive approach on a detailed level is still lacking. In addition, this study finds that the number of dedicated and specialised energy professionals employed in the industries is yet negligible. The cumulated results show that energy efficiency is mostly disrupted due to inadequate support from preeminent administration and bureaucratic intricacy. Energy blueprint cost-saving due to less use of energy and rules and regulations were distinctively signified as most imperative drivers for energy efficiency. On the other hand, lack of information is found to be the most significant barrier to consult energy service companies. Analysis of the country's energy usage and supply-demand relationship points towards insufficient energy efficiency measures and energy management practices in the country. The study also finds that energy efficiency could be improved by 8%–10% through the practice of energy management. Our findings, besides pointing out specific issues to be tackled in the specific context of investigation, pave the way for further research over industrial energy efficiency in developing countries.
Energies
Bangladesh faced a substantial growth in primary energy demand in the last few years. According t... more Bangladesh faced a substantial growth in primary energy demand in the last few years. According to several studies, energy generation is not the only means to address energy demand; efficient energy management practices are also very critical. A pertinent contribution in the energy management at the industrial sector ensures the proper utilization of energy. Energy management and its efficiency in the textile industries of Bangladesh are studied in this paper. The outcomes demonstrate several barriers to energy management practices which are inadequate technical cost-effective measures, inadequate capital expenditure, and poor research and development. However, this study also demonstrates that the risk of high energy prices in the future, assistance from energy professionals, and an energy management scheme constitute the important drivers for the implementation of energy efficiency measures in the studied textile mills. The studied textile industries seem unaccustomed to the dedic...