RISTCON 2021http://ir.lib.ruh.ac.lk/xmlui/handle/iruor/44772024-03-29T08:57:31Z2024-03-29T08:57:31ZFabrication of a dual sensor hot-wire anemometer to measure wind directionDissanayaka, I. S.Jayathileke, K. P. Shttp://ir.lib.ruh.ac.lk/xmlui/handle/iruor/47082021-12-20T10:33:02Z2021-02-17T00:00:00ZFabrication of a dual sensor hot-wire anemometer to measure wind direction
Dissanayaka, I. S.; Jayathileke, K. P. S
Hot-wire anemometers are wind measuring instruments that work on the principle of convectional heat transfer that takes place from an electrically heated hot-wire. They are well popular for the reliable, error-less wind measurements. In addition, their less maintenance cost, lack of mechanical parts and taking comparably less space are some advantages over the other wind measuring instruments. Single sensor hot-wire anemometer allows only for measuring wind velocity. But, dual-sensor hot-wires anemometer allows two-dimensional airflow measurements, which will yield wind velocity and wind direction. A dual-sensor hot-wire probe (X-probe) was constructed using Nichrome (NiCr) as hot-wire material. Dual sensors were fixed to the prongs of the hot-wire anemometer, being perpendicular to each other. X-probe calibration was conducted for velocity fixed winds obtained from a wind generator. It was performed for different orientations of X-probe, facing the wind flow generated by the wind generator. Voltages across two hot-wire sensors were analyzed for different orientations of the two hot-wires of the sensor. Each pair of voltages exhibited a unique variation with different orientations of the two hot-wires sensors to different wind flows. Each set of voltages was plotted and fitted to King's law formula which contains three parameters. Parameter values were used to create a calibration curve. X-probe was tested inside the laboratory using the wind generator and it produces a very accurate value of wind direction and velocity. The look-up table method was used to extract the wind direction and wind velocity. Wind measurements in the outside environment were tested using the X-probe and it showed a fluctuation of the wind velocity and direction.
2021-02-17T00:00:00ZUser-friendly interface design to disseminate best agricultural practicesShanadi, A. T.Samaraweera, G. C.Wathugala, D. L.Indika, W. A.Madushika, M. K. S.Gunawardana, D. A.Y. K.http://ir.lib.ruh.ac.lk/xmlui/handle/iruor/47072021-12-20T10:26:46Z2021-02-17T00:00:00ZUser-friendly interface design to disseminate best agricultural practices
Shanadi, A. T.; Samaraweera, G. C.; Wathugala, D. L.; Indika, W. A.; Madushika, M. K. S.; Gunawardana, D. A.Y. K.
The main purpose of the Good Agricultural Practices (GAPs) is to produce foods by applying ecologically sustainable agricultural methods that are safe and wholesome to consumers. Therefore, farming with GAPs can eliminate vast environmental and health problems in modern industrial agriculture. Information and Communication Technology (ICT) has become one useful tool in modern agriculture that provides day-to-day information to the farmers for successful farming. “Govi-Nena” is one of such mobile applications is developing to provide real-time information to farmers in Sri Lanka. Therefore, the aims of this study to design user-friendly interfaces to disseminate guidelines of GAPs and potato was selected as the test crop in designing the model. First, primary data were gathered through two pre-tested questionnaires from 100 potato farmers in Nuwara-Eliya and Badulla districts to evaluate the present status of potato cultivation in Sri Lanka. The secondary data was collected from various reliable sources such as books, previous records, research articles, the internet etc. Then user-friendly interfaces designed according to the modern User Interfaces (UI) and User Experience design (UX) theory, to disseminate guidelines for GAPs. It was included important guidance, knowledge and vital information on GAPs for potato cultivation in Sri Lanka. These user-friendly interfaces will help farmers to get the guidance of the GAPs such as land preparation by conserving the soil and minimize soil erosion, accurate knowledge and vital information and also facilitates a history record book and adversary services for farmers on the right time and easy manner through “Govi-Nena” mobile-based application.
2021-02-17T00:00:00ZA Study on National Economy using a Higher order Dynamical SystemSewwandi, M. D. S.Shanthidevi, K. C. N.http://ir.lib.ruh.ac.lk/xmlui/handle/iruor/47062021-12-20T10:20:03Z2021-02-17T00:00:00ZA Study on National Economy using a Higher order Dynamical System
Sewwandi, M. D. S.; Shanthidevi, K. C. N.
Higher order Dynamical systems are now used in all areas of Science. In particular, higher order dynamical systems in economics have been developed rapidly because of the dynamic nature of the economy in the view of applications and use of the computer technology in the view of analyzing tools.
In this work we have developed a second order affine dynamical system that models the economy. This dynamical system is a variation of the Samuelson accelerator-multiplier model which was first developed in 1939.
Three assumptions on Consumer Spending, Investment and Government Spending were considered in this model by which we could understand how each component of the model affects the long-term behavior of the economy. Once we understand how the behavior of the economy get affected by those assumptions, we can modify the existing components.
In this work we have modified the Government Spending assumption and investigated on how alternate approaches could affect the economy both positively and negatively. Results indicated that Immediate Government Response can stabilize unstable situations. So chaotic behavior is not applicable in these cases. If there is a delay in the Government Response, such as 1or 2-time unit delay in action, the response could have either a deleterious effect or no effect at all. We further observed that, greater the delay, the effect of the government control could get worsen.
2021-02-17T00:00:00ZMarkov Chain Model for predicting the Share Price of Canadian Stock MarketAnuthrika, T.Thanusika, T.http://ir.lib.ruh.ac.lk/xmlui/handle/iruor/47052021-12-20T10:14:01Z2021-02-17T00:00:00ZMarkov Chain Model for predicting the Share Price of Canadian Stock Market
Anuthrika, T.; Thanusika, T.
The stock prices are vital in the investor’s point of view to make decision regarding their investment. So, the success of the investor, especially in the stock market, depends a great deal on the choice of the decision taken by the investor. Therefore, this paper studies a Markov chain application on stock market price. This paper provides a Markov chain analysis for forecasting the stock prices of five Canadian banks; Royal Bank of Canada (RBC), Toronto-Dominion Bank (TD), Bank of Nova Scotia (Scotia bank) (BON), Bank of Montreal (BMO) and Canadian Imperial Bank of Commerce (CIBC) in Canada. The closing prices of each trading day of each bank were obtained from the Yahoo finance website between Jan 2019 and April 2020. Two methods have been adopted to describe the state of the system. For each bank, the states were considered as gains or losses for model 1 and large increments, low increments, small increments, small losses, moderate losses, and high losses for Model 2. The Transition probabilities, steady state probabilities and mean recurrent time were obtained for these two models and compared among the banks. Based on the model 1, it is revealed that the chance of getting gain (55%) is comparatively high for all the banks. According to model 2, the chance of getting small increment is high for each of the five banks. This is a good sign for investors; they do not get any considerable large loss. Also, noted that, for BON shareholders there is 48% chance of getting small increment in the near future.
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