Nihal Senanayake | Open University of Sri Lanka (original) (raw)
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Papers by Nihal Senanayake
Scientific & Academic Publishing, 2020
Food waste is considered by many people as non-useful materials. Global food wastage is approxima... more Food waste is considered by many people as non-useful materials. Global food wastage is approximately one third of the food produced in the world for human consumption every year. The total food wastage by consumers in industrialized countries is almost equal to the entire food production in sub-Saharan Africa. Food wastage creates environmental pollution problems in addition to the waste of resources. Many people are of little concern about the food wastes they consume because they have no clear awareness about the individually accumulated wastage over a period. At present there is no system to provide information on individual food waste and to make people aware of the magnitude of impact they create on the environment as well as incurring of high cost by obtaining unwanted amounts of food and then discarding. This study, therefore, aimed to design a system in view of reducing food wastes in organizations where food is supplied to the employees during working period. Philosophy behind the study is to make the people aware of their individual food wastes just after consumption and cumulative wastes, by providing information through a smart bin, thus encouraging the people to self-judge on how much they contribute to the problem and make necessary adjustments in obtaining the food from counter. A smart waste bin was designed and assembled with necessary controls to identify the user and measure the individual food wastes, and to calculate cumulative waste done each worker over a period.
Scientific & Academic Publishing, 2020
Soil nitrogen, phosphorus, potassium, and organic matter are the main factors affecting the yield... more Soil nitrogen, phosphorus, potassium, and organic matter are the main factors affecting the yields in crop production. It has been a common problem in many developing countries that fertilizers and crop protection chemicals are used with little or no awareness of available soil nutrients. The requirements of these external inputs differ from crop to crop, and with the existing soil conditions. The advice provided by the agricultural extension officers is mainly based on past experiences with no assessments of individual lands. On the other hand, standard laboratory procedures to determine the soil conditions take a long time to prepare the soil samples for testing and obtain the results. When the elements essential for plant nutrition are low in availability or unbalanced, then chemical fertilizers and soil amendments are required to be added to enhance crop yields in right amounts depending crop requirements. Incorrect fertilizer application or unbalanced/inadequate availability of nutrients can lead to depletion of soil nutrient reserves and loss of plant nutrients. Lack of balanced nutrients also encourages excessive uptake of these nutrients supplied in excess, but with no benefit. On the other hand, excessive fertilization is uneconomic, and is a waste of scarce resources. Agriculture extension officers do not have enough details and means to guide the farmers for fertilizer usage to avoid these unfavorable situations in crop production. In this study an instrument was developed for in-situ assessment of soil, P, K and OM which can be used by agriculture field officers. The proposed instrument can analyze the past data in the area and test the soil parameters in the field, and recommend soil P, K and OM requirements. The equipment has the capability to test soil pH and Electrical conductivity in the field using standard Laboratory sensors and to determine Soil, P, K, and OM by processing unique algorithms built from past data. This will help agriculture field officers to recommend suitable fertilizer quantities, hence help reduce the excessive chemical usage and gradual establishment of the chemical balance in the soil.
Teaching and Learning in a Digital World, 2018
International journal of energy engineering, 2013
Bio mass gasification to produce combustible gas is one of the pro mising sustainable energy opti... more Bio mass gasification to produce combustible gas is one of the pro mising sustainable energy options available for many countries. At present, a few s mall scale co mmun ity based power generation systems using biomass gasifiers are in operation in Sri Lan ka. However, due to insufficient knowledge on the relationships between important parameters, these systems are not operating properly in full capacity. This stands as an obstacle to further expand the use of gasifier technology. Hence, in o rder to imp rove the knowledge of the gasification and to simp lify the process, researches are being carried out to determine the relat ionships between different parameters and to optimize the power generation. The object ive of this study was to identify most influential parameters related to fuel wood gasification using a down draft gasifier to improve the gasification processes. A downdraft gasifier of 10kW electrical capacity was used to study the effect of equivalence ratio (ER) on the ...
2017 IEEE Global Engineering Education Conference (EDUCON), 2017
Open Distance Learning is gaining popularity as a successful alternative for on-campus higher edu... more Open Distance Learning is gaining popularity as a successful alternative for on-campus higher education especially with the emergence of web based platforms which enable the online delivery of courses worldwide. This emerging educational pedagogy can successfully be employed as means of capacity building of the people living in the less fortunate parts of the world where higher education especially at master level are scarce. This paper presents a two-year collaborative master study programme in sustainable energy engineering offered in synchronous with an on-campus study programme conducted by the KTH Royal Institute of Technology of Sweden, to students of Sri Lanka, which was facilitated by the Open University of Sri Lanka. The paper describes the need of such a programme, the format of course delivery and assessment thereof, plus the benefits gained. This programme has produced 72 post graduates in Sri Lanka alone and more than 200 distant postgraduates worldwide in the field of ...
Using biomass gasification to produce combustible gas is one of the promising sustainable energy ... more Using biomass gasification to produce combustible gas is one of the promising sustainable energy options available for many countries. At present, a few small scale community based power generation systems using biomass gasifiers are in operation in Sri Lanka. However, due to the lack of proper knowledge, these systems are not being operated properly in full capacity. This stands as an obstacle for further expansion of the use of gasifier technology. The objective of this study was to identify the most influential parameters related to fuel wood gasification with a down draft gasifier in order to improve the gasification processes. A downdraft gasifier of 10kW electrical capacity was used to study the effect of equivalent ratio (Actual air fuel ratio to Stoicheometric air fuel ratio: ER) on the specific gas production, the heating value of gas produced and the cold gas efficiency using three throat diameters (125mm, 150mm and 175mm). Six trials were carried out for each throat diame...
International Review of Mechanical Engineering-IREME, 2012
A wire-on-tube condenser of a domestic refrigerator (model NST200, manufactured by Regnis Lanka P... more A wire-on-tube condenser of a domestic refrigerator (model NST200, manufactured by Regnis Lanka Plc) was modified by adopting the condenser heat transfer model developed in previous studies. The modified condenser was tested and compared with the present condenser to assess the improvements in total heat transfer through the condenser and the mass of the condenser. Different values for refrigerant tube pitch, number of tubes, and number steel wires were used to arrive at the optimum combination of these variables. The selection of the optimum combination was done based on total heat transfer and mass. The modified condenser showed a significant improvement (33%) in heat transfer. The evaporator capacity increased by 14% whereas COP increased by 24%.
2019 IEEE Global Engineering Education Conference (EDUCON), 2019
This paper presents the analysis of innovative features of the remote mode summer school and bene... more This paper presents the analysis of innovative features of the remote mode summer school and benefits as perceived by the participants. The summer school has been identified as highly valuable for the participants to expand their knowledge on sustainable development and the economic/financial conditions on a global scale encouraging them to propose creative solutions for real problems. According to the feedback, the program features were well appreciated and inclusion of some activities is proposed to enhance the scope and further development. One of them is to include participants in different locations in the project teams. This could have been mentioned due to the fact that participants of the European countries mostly selected projects with high technological concepts and this was not case for Asian group, probably due to the difference of penetration in high technology to the society. Despite all positive feedbacks, running a summer school like this remotely does not yet delive...
Remote mode higher education at postgraduate level is becoming popular among students because of ... more Remote mode higher education at postgraduate level is becoming popular among students because of flexible learning opportunity and the accessibility to study programs offered by renowned universities in the world. Fast development of internet facilities and learner management systems along with the development of remote educational pedagogy have been the driving force behind the acceptance and development of distant mode study programs. The success of such a study programs is largely affected by several factors that are unique to the university that offers the study program and the demography of participants as well as infrastructure and the student support available at the receiving end.
2018 IEEE Global Engineering Education Conference (EDUCON), 2018
Remote mode study programs at master degree level are becoming more popular than undergraduate le... more Remote mode study programs at master degree level are becoming more popular than undergraduate level programs. Students after graduation with Bachelors degree very often are employed and the most appropriate mode for them to pursue higher studies is the remote mode. Postgraduate programs with one or two year duration mostly focus on specific areas of research based industrial application. Traditional remote education is thought to be more centered on web based on-line programs with a little opportunity for teacher student interaction and interaction with peers. In such programs motivation for studies has been a problem and as a result many students drop off and also those remain in the program for prolonged periods do not show good performance. One of the reasons for failures of students in remote studies is the isolation leading to discouragement for the completion studies. A remote mode Master Degree Program in Environomical Pathways for Sustainable Energy Systems (MSc-SELECT), co...
… Review of Research in Open and …, Jan 1, 2012
Motivating factors that affect enrolment and student performance in an ODL engineering programme.
Scientific & Academic Publishing, 2020
Food waste is considered by many people as non-useful materials. Global food wastage is approxima... more Food waste is considered by many people as non-useful materials. Global food wastage is approximately one third of the food produced in the world for human consumption every year. The total food wastage by consumers in industrialized countries is almost equal to the entire food production in sub-Saharan Africa. Food wastage creates environmental pollution problems in addition to the waste of resources. Many people are of little concern about the food wastes they consume because they have no clear awareness about the individually accumulated wastage over a period. At present there is no system to provide information on individual food waste and to make people aware of the magnitude of impact they create on the environment as well as incurring of high cost by obtaining unwanted amounts of food and then discarding. This study, therefore, aimed to design a system in view of reducing food wastes in organizations where food is supplied to the employees during working period. Philosophy behind the study is to make the people aware of their individual food wastes just after consumption and cumulative wastes, by providing information through a smart bin, thus encouraging the people to self-judge on how much they contribute to the problem and make necessary adjustments in obtaining the food from counter. A smart waste bin was designed and assembled with necessary controls to identify the user and measure the individual food wastes, and to calculate cumulative waste done each worker over a period.
Scientific & Academic Publishing, 2020
Soil nitrogen, phosphorus, potassium, and organic matter are the main factors affecting the yield... more Soil nitrogen, phosphorus, potassium, and organic matter are the main factors affecting the yields in crop production. It has been a common problem in many developing countries that fertilizers and crop protection chemicals are used with little or no awareness of available soil nutrients. The requirements of these external inputs differ from crop to crop, and with the existing soil conditions. The advice provided by the agricultural extension officers is mainly based on past experiences with no assessments of individual lands. On the other hand, standard laboratory procedures to determine the soil conditions take a long time to prepare the soil samples for testing and obtain the results. When the elements essential for plant nutrition are low in availability or unbalanced, then chemical fertilizers and soil amendments are required to be added to enhance crop yields in right amounts depending crop requirements. Incorrect fertilizer application or unbalanced/inadequate availability of nutrients can lead to depletion of soil nutrient reserves and loss of plant nutrients. Lack of balanced nutrients also encourages excessive uptake of these nutrients supplied in excess, but with no benefit. On the other hand, excessive fertilization is uneconomic, and is a waste of scarce resources. Agriculture extension officers do not have enough details and means to guide the farmers for fertilizer usage to avoid these unfavorable situations in crop production. In this study an instrument was developed for in-situ assessment of soil, P, K and OM which can be used by agriculture field officers. The proposed instrument can analyze the past data in the area and test the soil parameters in the field, and recommend soil P, K and OM requirements. The equipment has the capability to test soil pH and Electrical conductivity in the field using standard Laboratory sensors and to determine Soil, P, K, and OM by processing unique algorithms built from past data. This will help agriculture field officers to recommend suitable fertilizer quantities, hence help reduce the excessive chemical usage and gradual establishment of the chemical balance in the soil.
Teaching and Learning in a Digital World, 2018
International journal of energy engineering, 2013
Bio mass gasification to produce combustible gas is one of the pro mising sustainable energy opti... more Bio mass gasification to produce combustible gas is one of the pro mising sustainable energy options available for many countries. At present, a few s mall scale co mmun ity based power generation systems using biomass gasifiers are in operation in Sri Lan ka. However, due to insufficient knowledge on the relationships between important parameters, these systems are not operating properly in full capacity. This stands as an obstacle to further expand the use of gasifier technology. Hence, in o rder to imp rove the knowledge of the gasification and to simp lify the process, researches are being carried out to determine the relat ionships between different parameters and to optimize the power generation. The object ive of this study was to identify most influential parameters related to fuel wood gasification using a down draft gasifier to improve the gasification processes. A downdraft gasifier of 10kW electrical capacity was used to study the effect of equivalence ratio (ER) on the ...
2017 IEEE Global Engineering Education Conference (EDUCON), 2017
Open Distance Learning is gaining popularity as a successful alternative for on-campus higher edu... more Open Distance Learning is gaining popularity as a successful alternative for on-campus higher education especially with the emergence of web based platforms which enable the online delivery of courses worldwide. This emerging educational pedagogy can successfully be employed as means of capacity building of the people living in the less fortunate parts of the world where higher education especially at master level are scarce. This paper presents a two-year collaborative master study programme in sustainable energy engineering offered in synchronous with an on-campus study programme conducted by the KTH Royal Institute of Technology of Sweden, to students of Sri Lanka, which was facilitated by the Open University of Sri Lanka. The paper describes the need of such a programme, the format of course delivery and assessment thereof, plus the benefits gained. This programme has produced 72 post graduates in Sri Lanka alone and more than 200 distant postgraduates worldwide in the field of ...
Using biomass gasification to produce combustible gas is one of the promising sustainable energy ... more Using biomass gasification to produce combustible gas is one of the promising sustainable energy options available for many countries. At present, a few small scale community based power generation systems using biomass gasifiers are in operation in Sri Lanka. However, due to the lack of proper knowledge, these systems are not being operated properly in full capacity. This stands as an obstacle for further expansion of the use of gasifier technology. The objective of this study was to identify the most influential parameters related to fuel wood gasification with a down draft gasifier in order to improve the gasification processes. A downdraft gasifier of 10kW electrical capacity was used to study the effect of equivalent ratio (Actual air fuel ratio to Stoicheometric air fuel ratio: ER) on the specific gas production, the heating value of gas produced and the cold gas efficiency using three throat diameters (125mm, 150mm and 175mm). Six trials were carried out for each throat diame...
International Review of Mechanical Engineering-IREME, 2012
A wire-on-tube condenser of a domestic refrigerator (model NST200, manufactured by Regnis Lanka P... more A wire-on-tube condenser of a domestic refrigerator (model NST200, manufactured by Regnis Lanka Plc) was modified by adopting the condenser heat transfer model developed in previous studies. The modified condenser was tested and compared with the present condenser to assess the improvements in total heat transfer through the condenser and the mass of the condenser. Different values for refrigerant tube pitch, number of tubes, and number steel wires were used to arrive at the optimum combination of these variables. The selection of the optimum combination was done based on total heat transfer and mass. The modified condenser showed a significant improvement (33%) in heat transfer. The evaporator capacity increased by 14% whereas COP increased by 24%.
2019 IEEE Global Engineering Education Conference (EDUCON), 2019
This paper presents the analysis of innovative features of the remote mode summer school and bene... more This paper presents the analysis of innovative features of the remote mode summer school and benefits as perceived by the participants. The summer school has been identified as highly valuable for the participants to expand their knowledge on sustainable development and the economic/financial conditions on a global scale encouraging them to propose creative solutions for real problems. According to the feedback, the program features were well appreciated and inclusion of some activities is proposed to enhance the scope and further development. One of them is to include participants in different locations in the project teams. This could have been mentioned due to the fact that participants of the European countries mostly selected projects with high technological concepts and this was not case for Asian group, probably due to the difference of penetration in high technology to the society. Despite all positive feedbacks, running a summer school like this remotely does not yet delive...
Remote mode higher education at postgraduate level is becoming popular among students because of ... more Remote mode higher education at postgraduate level is becoming popular among students because of flexible learning opportunity and the accessibility to study programs offered by renowned universities in the world. Fast development of internet facilities and learner management systems along with the development of remote educational pedagogy have been the driving force behind the acceptance and development of distant mode study programs. The success of such a study programs is largely affected by several factors that are unique to the university that offers the study program and the demography of participants as well as infrastructure and the student support available at the receiving end.
2018 IEEE Global Engineering Education Conference (EDUCON), 2018
Remote mode study programs at master degree level are becoming more popular than undergraduate le... more Remote mode study programs at master degree level are becoming more popular than undergraduate level programs. Students after graduation with Bachelors degree very often are employed and the most appropriate mode for them to pursue higher studies is the remote mode. Postgraduate programs with one or two year duration mostly focus on specific areas of research based industrial application. Traditional remote education is thought to be more centered on web based on-line programs with a little opportunity for teacher student interaction and interaction with peers. In such programs motivation for studies has been a problem and as a result many students drop off and also those remain in the program for prolonged periods do not show good performance. One of the reasons for failures of students in remote studies is the isolation leading to discouragement for the completion studies. A remote mode Master Degree Program in Environomical Pathways for Sustainable Energy Systems (MSc-SELECT), co...
… Review of Research in Open and …, Jan 1, 2012
Motivating factors that affect enrolment and student performance in an ODL engineering programme.