http://repo.lib.jfn.ac.lk/ujrr/handle/123456789/6127 2026-04-25T13:27:55Z http://repo.lib.jfn.ac.lk/ujrr/handle/123456789/6156 Controls of solar power systems for grid connected and islanded mode operations Nagaratnam, R.; Thiriambahasharma, K.; Ratnakumar, R.; Manchukan, Y.; Kanagasundram, A.; Arulampalam, A. Continuous supply of electricity, when there are supply constrains is a major challenge. Environmental concerns and non availability of fossil fuels increases the demand for the use of renewable energy sources such as solar. A domestic or an institutional customer can support the country by the proper usage of solar Resources. Further the usage of a battery storage combined with the solar panel can improve this. This paper analyses the domestic/ institutional usage of solar panels, (i) with and (ii) without a battery storage, for both cases of (i) with grid and (ii) standalone operation, depends on the availability of solar irradiation in a day. Here a typical domestic/institutional solar power system taken into the study and suitable sizes of solar panel, battery storage were selected to achieve a reliable and smooth operation of the system. The whole system is modeled using PSCAD simulation. The design of the controllers ensured the proper operations of grid connected and standalone mode of the system. Further MPPT control also used in such a way to ensure the optimum usage of solar power. The simulation results shows that this arrangement improves the power availability for domestic/institutional customers even during the power failure periods. 2022-01-01T00:00:00Z http://repo.lib.jfn.ac.lk/ujrr/handle/123456789/6155 Vehicle Parking Mobile Network Muralitharan, R. Universal Software Defined Radio Peripheral (USRP) and Banana pi board can be used to configure a vehicle parking mobile network. The base station is created in the center of the parking area. The base station can issue useful information to the drivers. The number of the vehicles in the parking area, amount of free space, and directions to the free space could be provided to the driver through the USRP base station. The base station sends text messages to the driver. The base station can provide the essential information to the driver through GSM network. Each driver has a GSM mobile device. The device will be connected to the vehicle parking mobile network. International Mobile Equipment Identification (IMEI) number is used to configure the network, between base station and the mobile devices. The mobile devices can be used by the drivers to get the essential details regarding the parking area. The information includes the necessary features of the parking area. The information would be provided to the driver from time to time. Multiple text messages will be provided to the driver. The text message contains all the necessary details about the parking area. 2022-01-01T00:00:00Z http://repo.lib.jfn.ac.lk/ujrr/handle/123456789/6154 Web crippling behaviour of LiteSteel Beams with edge-stiffened web openings under End-Two-Flange load case Elilarasi, K.; Janarthanan, B.; Athapaththu, D.; Poologanathan, K.; Perampalam, G. Cold-Formed Steel (CFS) members are widely used with openings in the floor system for various service purposes such as power, telecommunication, and internet cables. Also, web crippling is becoming vulnerable owing to the impact of web openings. However, stiffened web openings are expected to increase the web crippling capacity and redeem a significant percentage of the actual capacity of the section without web openings while allowing the service integration. This paper presents the numerical study on the web crippling capacity of LiteSteel Beams (LSB) with centred beneath stiffened web openings under the End-Two-Flange (ETF) load case. Although Rectangular Hollow Flange beams are investigated with centred beneath web openings, no studies have been carried out regarding stiffened web openings. Therefore, results from previous studies on the web crippling of channel sections with stiffened web openings were validated in terms of strength and failure mode; a good agreement was observed in the validation. Subsequently, parametric study was conducted using Abaqus; Finite Element Analysis (FEA) software, by considering various section depths, bearing plates, yield strengths, web opening ratios, thicknesses, and stiffener lengths of the hole. The FEA results showed much improvement in the web crippling capacity with edge-stiffened openings and the FEA results were analysed with various parameters for better predictions in terms of web crippling strengths. 2022-01-01T00:00:00Z http://repo.lib.jfn.ac.lk/ujrr/handle/123456789/6153 Feasibility of Cement Mortar System with Industrial Metal Fibre Waste Perera, K.D.Y.G.; Ahamed, Y.L.F.; Somarathna, H.M.C.C. The traditional cement mortar has limited characteristics. Because of the lack of expected results, the engineering scope has focused on alternative materials instead of using the traditional constituents. As a result of that different types of fibres have been used in the past. In addition, the electrical distribution cables no longer operate for power transmission purposes when the length is not adequate and after it reaches its’ end of life and the disposal methods are not eco-friendly. Therefore, the purpose of the study was to evaluate the feasibility of cement mortar with the metal fibre waste which was extracted from electrical distribution cables. 1.35 mm diameter aluminium fibres were used by changing their volume ratio at four levels 0.5%, 1.0%, 1.5%, and 2.0%. Wet and dry density and compressive tests were mainly carried out to determine the behaviour of the developed mortar systems. The wet, dry densities and modulus of elasticity were increased with the fibre addition. The maximum compressive strength of the MFRM was increased respect to reference mortar by 19.7% (3rd day), 19.8% (7th day), 11.7% (28th day dry) and 25% (28th day wet). The overall results of the study emphasized the mortar mix with 1.5% of fibres performed well in all mechanical tests and also it showed. 2022-01-01T00:00:00Z