Research Symposium-2013

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Factors Affecting on Consumer Buying Behaviour in Fast Food Market: Theory of Planned Behavior Model
(Uva Wellassa University of Sri Lanka, 2013) Atapattu, A.M.N.D.; Mahindarathne, M.G.P.P.
Fast food restaurants are becoming widespread all over the world, both in developed and developing countries like Sri Lanka and there has been number of socio-economic and cultural factors that influence the fast food consumption. Increasing fast food intake, especially among younger generation has led to number of serious implications such as increased incidents of obesity and non-commutable diseases. Ashakiran and Deepthi (2012) reported that there is a trend of dramatic increase of the obesity and obesity associated serious health problems such as type 2 diabetes, heart disease and certain cancers. Studying the fast food consumption behaviour of the consumers is very important to have interventions in promoting healthy eating behaviours. There are several comprehensive theories developed to study the consumer behaviour and among those the Theory of Planned Behavior (TPB) is very popular model. The TPB posits that a person's behavioural intention is based upon three antecedents attitude, subjective norm, and perceived behavioural control (Azadbakht et al.,2013).Attitude signifies the degree to which a person has a favourable or unfavourable evaluation of the behaviour in question. The subjective norm summarizes the belief of other people concerning how the individual should behave in the situation and perceived behavioural control summarizes the factors, either internal or external that can help or hinder the performance of the behaviour. Accordingly TPB model was adopted in this research to study the fast food consumption behaviour of the consumers in three selected district of Sri Lanka. Methodology A Sample of 200 consumers who are in age between 15-40 years were recruited from 3 districts Kurunegala, Kandy and Badulla. Primary data were collected in a consumer survey carried out by interview with the aid of structured questionnaire. The questionnaire was developed based on the Theory of Planned Behaviour (TPB) model (Figure 1) and it was pre-tested to check the reliability. First part of the questionnaire was included questions to obtained information about the demographic information of consumers. Second part of questionnaire was structured in such way to collect the information pertaining to the construct of the TPB variables attitude, perceived behavioural control, and subjective norm.
Identification of Optimized Quantity of Methyl-Testosterone Incorporated Feed for Sex Reversal of Nile Tilapia
(Uva Wellassa University of Sri Lanka, 2013) Jayawickrama, H.V.M.; Liyanage, N.P.P.; Rajapaksa, R.M.G.N.; Wathurawadu, W.A.K.C.K.
Tilapia is likely to be the most important aquaculture fish species in the 21 century (Fitzsimmons, 2000). Tilapia has certain favourable characteristics for aquaculture such as more tolerant to adverse environmental conditions; survive at low dissolve oxygen, relatively fast growth and efficient food conversion (Yi et al., 1996; Penna Mendoza, 2005). One of the main impediments in tilapia grow out production at commercial scale is its rapid reproduction rate. It attains sexual maturity at an early age and reproduces after every 4-6 weeks in the ponds and start to reproduce in culture ponds resulting a low production. This can be controlled by stocking ponds with all male tilapia produced with mono-sex production technique. Tilapia has sexual growth dimorphism in which males grow faster and show more standard size than females (Mair and Little, 1991). Manual process by visual examination, hybridization, gene manipulation and masculinisation via steroid hormone are commonly used techniques for production of mono-sex tilapia. Use of the hormone17α-Methyl Testosterone (MT) to induce sex reversal in farmed tilapias has become a common practice in many parts of the world. MT is a simple and reliable way to produce all-male tilapia stocks, which consistently grow to a larger/more uniform size than mixed sex or all-female stocks. MT treatment could still be perceived as hazardous to tilapia consumers if MT is applied at higher than the recommended dosages, or is used for longer periods. Moreover, there is no evidence that higher dosages or longer treatment periods improve the sex reversal effectiveness of MT. In fact research findings indicate that MT is actually less effective if the recommended dosage and duration of treatment are exceeded (Yoshikawa and Oguri, 1978). Hence, identification of minimal quantity of methyl testosterone incorporated feed for sex reversal of tilapia is more critical for the fish farmers. It helps to minimize the cost that needs to bear for hormone and feed. Lower usage of hormone treated feed will lower the accumulation it into the natural environment as well. The study was carried out at the Aquaculture Development Center (AQDC) in Polonnaruwa. The selected sample size was 3750 tilapia individuals on fry stage and twelve tanks were used for the study. All tanks were cleaned through the scrubbing of algae and allowed to dry for three days. The water was filtered through sand and gravel filter media and pumped into the tanks. The outlet pipes were sealed with plastic caps. Tilapia fry was taken from the Polonnaruwa Aquaculture Development Center (AQDC) from the same spawning. Fry were quarantined for 2 to 3 days. The quarantined fry with average body weight of 0.02 ± 0.001 g were randomly stocked in twelve tanks at the rate of 250 fry per tank. Each tank was covered with small mesh net material to block the entrance of predators. In order to take 60 mgMT/kg, 0.5g of testosterone powder was measured using an electronic analytical balance (Model: FA1004N) with 0.1 mg accuracy and dissolved in one litter of 95% “Methyl Alcohol” solution. 120 ml was taken and spread over 1 kg of powder form commercial tropical fish feed (FF 00) and kept at room temperature for one day to evaporate the excess methanol solution. Fifty individuals from each tank were weighed after blotting with paper towel. Based on data obtained mean body weight was calculated. Under treatment 01, all tilapia fry was given 3% of their mean body weight. Respectively, 6% for treatment 02, 9% for treatment 03 and finally 12% for treatment 04 were continued up to two weeks. After two weeks, fifty individuals were randomly taken from each tank and body weight was measured and mean body weight for each tank was calculated separately. Using same methodology individual weights was measured at every other week until the end of research period and mean body was calculated. The amount of hormone incorporated feed for the individual and total amount of hormone utilized were calculated for each treatment according to the mean body weight and fed with those new values. After four weeks, tilapia fingerlings were fed with usual commercial tropical fish feed (FF 01) for another three weeks and at the eighth week, the amount of male, female was recorded by observing the genital papilla of the advance fingerlings using methylene blue. The results were analysed using Minitab 16 statistical software. Survival rates and percentage male production were analysed using analysis of variance (ANOVA) in order to determine the differences among treatments at 95% significance level.
Reducing the Time of Coir Retting by Changing the Conditions of Microbial Environment
(Uva Wellassa University of Sri Lanka, 2013) Wimalasena, P. H. T. N.; Chandrasena, G.
The coir industry in Sri Lanka had a great history as a main coconut based industry which contributing to the economy of Sri Lanka. There are two types of coir are produced in Sri Lanka as Brown fiber and White fiber. Sri Lanka is the largest supplier of brown fiber to the world. Sri Lanka produces about 36% of the world brown fiber production and exports of coir and coir products amounted to rupees 11.6 billion in 2008 (CDA, Coconut Statistics - 2008). But today Sri Lanka has faced to difficulties because of the low productivity compared with other competitor countries. Due to longer retting period and augmenting the microbial activities is one way of shortening retting time. According to Fernando et al., (2010) Bacillus firmus, Bacillus macerans and Bacillus badius bacteria can use to obtain good quality bristle fiber within 21 days. The coconut husk which is a fibrous material that covers the fruit of Cocos nucifera is the raw material for extracting coir fiber. The retting process is responsible for the separation of bristle fiber from the husk and it undergoes two distinguished physical and biological changes. The biological process can be accelerated by enriching the retting media with microbial nutrients. Therefore, this study was done to reduce the retting time of coir by changing the microbial environment of retting tank and to increase the productivity of Sri Lankan bristle fiber. Methodology Retting of coir and the microbial studies were done at the microbiology laboratory of Uva Wellassa University in Sri Lanka. Coir extraction and quality analysis were done at Coir Research and Development Institute in Nattandiya. Coconut husks with same maturity and same length were used and then crushed and cut in to pieces with similar width. The retting was done in three stages; the preparation of nutrient media, changing the pH of retting environment and aeration the retting tank. To enrich retting media there were two nutrient mixtures as 50% of Coconut water + 6 g Sago + Fresh water and 75% of Coconut water + 6 g Sago + Fresh water mixture. The total volume of the retting tank was 14 L. There were two nutrient levels as 50% of nutrient media from total volume of retting tank and 75% of nutrient media from total volume of the retting tank. There were six treatment combinations and the control. Treatments were arranged according to 3x2 factorial design. Six increasing retting days were used as 7, 14, 21, 28, 35 and 42 days. At each week microbial studies and coir quality analyses were done. Total plate count of microorganisms was taken at weekly intervals to determine the change of microbial population density during retting. The pH value of the retting media was adjusted by adding 1N Sodium hydroxide (NaOH) to the media at first day of retting. The aeration was done by using air pump in 3 L/min output and 0.012 Mpa pressure (Model U-8800, BOYU International village, North city, Raoping, Guangdong, China). The aeration level was same for each and every retting tank. After completing above three main stages the prepared 20 husk pieces of coconut husks were added into each treatment and also to the control. Three husk pieces were taken out from each treatment in weekly intervals and defiberd using defibering machine.
Determination of Optimal Auxin and Cytokinin Levels for Meristem Culture of Sugarcane (Saccharum Hybrid Spp.): Variety SL 96 328
(Uva Wellassa University of Sri Lanka, 2013) Rathnayaka, R.M.B.S.; Alwis, L.M.H.R.; Wijesuriya, A.
Non-availability of quality sugarcane planting material is a major constraint for cane production and sugar industry expansion in Sri Lanka. The Crop Improvement Division of the Sugarcane Research Institute of Sri Lanka actively engaged in the development of protocols in quality planting material production through micro propagation and in the other rapid sugarcane multiplication techniques (Wijesuriya et al., 2010). Concentration of phyto-hormones has been identified as the most critical factor that controls and interacts with the varieties in formation of multiple shoots and root formation in culture (Wijesuriya and Teruya, 1988). The Sugarcane Research Institute usually uses the standard MS medium with the concentration of 0.2 mg/l 6 - Benzylaminopurine (BA) and 0.001 mg/l Kinetin (KIN) for multiple shoot formation and gelrite medium for first culture and liquid medium for passage culture. For root formation in multiple shoots, MS medium added with α-Naphthalene acetic acid (NAA) 0.2 mg/l, Indol-3 butyric acid (IBA) 2 mg/l and sucrose 60 g/l have been identified as the most effective combination. However these phyto-hormone combinations may or may not produce optimum output for different varieties under culture. This study was conducted to determine the optimal levels of shooting hormones (BA and KIN) and rooting hormones (NAA and IBA) in particular to the meristem culture of newly-bred sugarcane variety SL 96 328 that is needed rapid multiplication for commercialization. Methodology This experiment was conducted at the Sugarcane Research Institute, Uda Walawe, Sri Lanka during the period, May to August 2013. Five levels of BA and five levels of Kinetin (Table 1) were tested for their effects on multiple shoot formation and shoot multiplication in passage culture in variety SL 96 328. For root initiation and development in multiple shoots, five levels of NAA and five levels of IBA (Table 2) were tested. Ten and 30 replicates were used respectively, in culturing meristem ex-plants in gelrite medium and in passage culture of single shoots in liquid medium in each hormone combination tested. For rooting, 20 replicates of multiple shoots with more or less similar size and vigour were used for each hormone combination.
Object Tracking Automated Camera
(Uva Wellassa University of Sri Lanka, 2013) Udangamuwa, E.M.D.T.E.; Rajapaksha, R.W.V.P.C.
Because of the advance in surveillance systems, object tracking has been an active research topic in the computer vision community over the last two decades as it is an essential prerequisite for analyzing and understanding video data. Tracking an object is to get its spatial- tempo information by estimating its trajectory in the image plane as it moves around a scene, which in turn helps to study and predict its future behavior. Enhancement of object tracking systems is building up a pan tilt moving cameras based on the movements of the detected object by combining the object tracking and computer vision technologies with microcontrollers. These systems are capable of continuing the tracking even though the object runs away from the boundaries of the normal still camera. Therefore, this research project was carried out to develop an object tracking Pan Tilt moving automatic camera with a low cost and better performance. Methodology This proposed system mainly consists of two modules such as a hardware module and a Software module. The Software module comprises of image processing algorithms and tracking algorithms. The hardware module consists with a Pan Tilt moving camera that was used to take video inputs and a Microcontroller to pass the control instructions to the Servo motors attached to the Pan Tilt mechanism. In this proposed system the video from the camera was processed using Digital Image Processing (Kirillov, 2008). The video was read as frames (Kirillov, 2009)and frame was a still image. The user was allowed to click on any object in this image using a mouse pointer. Then the color of the selected point was read as RGB values. The colors of the image were filtered out according to the selected color. Using a Color filtering algorithm it was able to filter the colors of the selected color and filled the rest of the image with black color. After the above process, developed algorithm was able to find the blobs with same color in the image and saved each and every blob in an array sorted by the size of the blobs. Then the largest blob was selected and drawn a rectangle around largest blob to clearly point out the selected object, and calculated the X and Y coordinates of the center of the rectangle with respect to the display pane. The above scenario was repeated for every frame. Thus any object in the frame can be tracked by its color, using the above algorithm. Universal Serial Bus (USB) communication was very important to read and write data to the external hardware. First the USB port which was used to communicated with the implemented hardware and the Software had to be configured. Once the baud rate was specified in the system, the serial port started to perform the communication. The Microcontroller attached to the serial port was programmed to read the data from the USB port, and the program run in a Computer was able to read the data from the Microcontroller via USB. In this proposed system, two servo motors were used and initially they were set to 90 degrees. Then in tracking algorithm two variables X and Y were declared and they were used to hold the values which were going to pass to the Microcontroller. Above X and Y variables also set to 90 degrees initially. Then calculated the display pane’s center X and Y coordinates. Subtracted the display pane’s center X coordinates from the largest blob’s center X coordinate, if the value was a negative value, and then decreased the variable value which hold the X value and wrote it to the serial port. If the subtract value was positive increased the variable value which hold the X value and wrote it to the serial port. If it equal to 0 did nothing. With parallel to the above process, subtracted the display pane’s center Y coordinates from the largest blob’s center Y coordinate, if the value was negative value, and then increased the variable value which hold the Y value and wrote it to the serial port. If the subtract value was positive decreased the variable value which hold the Y value and wrote it to the serial port. If it equal to 0 did nothing. These two parallel processes executed until the program stopped inside an infinite loop. The Microcontroller was programmed to accept those two values and it was programmed to identify the X and Y values uniquely and pass correct values to relevant servo motors. This algorithm and the programmed microcontroller kept the tracked object in the center of the display pane always by rotating the camera towards the object.
Phenotyping of Breeding Populations in Complement with Molecular Markers to Select Submergence Tolerant Rice (Oryza sativa)
(Uva Wellassa University of Sri Lanka, 2013) Gunadasa, J.G.D.C.; Alwis, L.M.H.R.; Samarasinghe, W.L.G.
Over 22 million hectares of lowland rain fed rice lands which occupy 18 % of global supply of rice are vulnerable to flash flooding worldwide and severe in Asian countries such as India, Bangladesh and Thailand. Most of these fields are cultivated with submergence tolerance landraces FR13A and FR43B with poor yield of 2 Mt/ha (Neeraja et al., 2007). As reported by the respective data sources, up to the end of January 2013, approximately 75,000 ha of paddy lands have been affected due to flood condition prevailed throughout the season. Therefore rice breeders should select the appropriate varieties for those areas with the higher yield. The study was undertaken to improve submergence tolerance in popular Sri Lankan rice variety Bg360 through identifying submergence tolerant individuals in BC2F1 population of Bg360 / Swarna Sub1 // Bg360 by phenotypic and molecular screening. Methodology This experiment was carried out in the field and laboratory at the Bio technology Division of Rice Research and Development Institute, Batalagoda which is in the Low country Intermediate Zone of Sri Lanka from May to October 2013. Two rice varieties namely Bg360 which is three and half month, submergence susceptible rice variety popularly grown in Sri Lanka, and Swarna sub1 which is a developed submergence tolerant rice variety grown in India and 526 seeds from BC2F1 population of cross of Bg360 and Swarna sub1 were grown in nursery trays for 10 days and submerged under 1 m height of water for 10 days. Number of survived plants were taken at de-submergence and number of recovered plants were numerated 14 days after de-submergence. Height difference was scored before and after submergence. A rapid DNA extraction protocol modified by Rice Research and Development Institute (RRDI), Bathalagoda was used for DNA extraction. Peatan a df DNA in she samples were confirmed by using agarose gel (1%) electrophoresis with 50 mV for 45 minutes. RM 219 microsatellite (Table 1) was used to dbtaeoa polymorphism between Bg360 and Swarna sub1. In PCR amplification, single preheat at 94 C, 35 cycles of denaturation at 94 C for 1 min, annealing at 59.1 C for 1 min and elongation for 72 C for 2 min and final extension at 72 C for 5 min were used for 15 µl of reaction volume which consist of 0.06 U Taq DNA Polymerase, 1X Buffer, 1.5 mM MgCl2, 0.1 nM dNTPs, 0.07 ϸmol forward and reverse Primers and 20 ng/µl template DNA. Agarose gel (2%) was used in 0.5X TBE buffer for electrophoresis for 2 hours under 50mV voltages to analyze the amplified DNA.
Development of a Sugar Free Two Bar Ice Palam by Incorporating ‘Kothala Himbutu’ (Salacia reticulata) Stem Extract
(Uva Wellassa University of Sri Lanka, 2013) Surige, D.N.; Abesinghe, A.M.N.L.; De Silva, K.I.U.
Salacia reticulata (Kothala Himbutu) is a woody climber native to Sri Lanka and it is a well known traditional medicinal plant used in Ayurvedic treatments (Anurakumara et al., 2010). Researchers found that the aqueous extract of the roots and stems of S. reticulata has sugar reduction ability and used for treating type II diabetic. Moreover the decoction of S. reticulata is used in the treatment of gonorrhea, rheumatism, skin diseases, hemorrhoids, itching, swelling, asthma, thirst, amenorrhea and dysmenorrheal (Anurakumara et al., 2010). Therefore, it is used in functional food industry and there are several Salacia based preparations available in the market (Ryanghyok et al., 2008). Current study aimed to develop a two bar ice palam which consists with two parts as shell and core. Shell of the product consisting with water ice incorporated with S. reticulata extract and the core comprises sugar free ice cream (lite ice cream).The objectives of this study was to find out the best method to prepare S. reticulata stem extract and to develop a sugar free two bar palam by incorporating S. reticulata extract. The current study was carried out at the Ceylon Cold Stores PLC, Kaduwela. First, the basic composition of the water ice was determined using preliminary trials. Then, water ice was prepared by incorporating S. reticulata stem extract. Several extraction methods were followed to find out the best method to prepare S. reticulata stem extract. The appropriate dosage of the extract was decided according to the Ayurvedic recommendations (Singh and Duggal, 2010) and recommendations of Industrial Technology Institute, Colombo, Sri Lanka. Total soluble solid content for the ice palam incorporated with S.reticulata were adjusted by adding ) in different combinations. Most compatible artificial sweetener combination was determined. Another trial was conducted to select the most compatible flavor of the final product. The best treatments were selected by evaluating the sensory attributes of the product using 7 trained panelists with five point hedonic scale. Then, ) consisting with 6% fat, 30.7% total solid and with a density of 1.09 kg/L. Finally, product was formulated with the developed S. reticulata incorporated water ice as the outer shell and lite ice cream as the inner core. Final product was assembled by GSL machine (GSL wrapper/GSL 12) at -32 °C. pH and the microbiological analysis were done to determine the Aerobic Plate Count (APC), E. coli, Coliform, Yeast and Mould counts of S. reticulata extract for 10 weeks of period under different storage temperatures. Physiochemical parameters and the microbiological analysis were done for the final product. Melting rate of the developed product was determined and compared with a commercially available water ice. A result of sensory evaluation was analyzed by Friedman non-parametric test using MINITAB 15 statistical software program and Microsoft Excel 2010.
A Preliminary Study on the Best pH Value of Water to Increase the Quality of Echinodorus Bleheri
(Uva Wellassa University of Sri Lanka, 2013) Withanage, W.A.S.; Bambaranda, B.V.A.S.M.; Jayamanne, S.C.; Fernando, M.A.G.C.
The Aquatic plant export industry of Sri Lanka has been developing rapidly. This industry requires a continuous supply of high quality plants. Echinodorus bleheri is one of the highest demanded aquatic plants in export market. Aquatic plants have adapted to life in water with a specific pH, Temperature, Electrical conductivity and may suffer from even a slight change. High quality plants can be supplied with in a short time period by finding the best pH value of water. In the world of plants each plant species is perfectly adapted to a certain pH range of the soil or water. Aquatic plant hobbyists are usually familiar with the different pH requirements of various plants and regulate the pH of water appropriately. Hydroponics is proved to have several advantages over soil gardening. The growth rate on a hydroponic plant is 30-50 percent faster than a soil plant. A nutrient solution for hydroponic systems is an aqueous solution containing mainly inorganic ions from soluble salts of essential elements for higher plants. Eventually, some organic compounds such as iron chelates may be present (Steiner, 1968). Changing the pH of a nutrient solution affects its composition, elemental speciation and bioavailability. An important feature of the nutrient solutions is that they must contain the ions in solution and in chemical forms that can be absorbed by plants, so in hydroponic systems the plant productivity is closely related with to nutrient uptake and the pH regulation (Marschner, 1995). Each nutrient shows differential responses to changes in pH of the nutrient solution. The proper pH values of nutrient solution for the development of crops, lies between 5.5 and 6.5. Plants need the right combination of nutrients to live, grow and reproduce. When plants suffer from malnutrition, they show symptoms of being unhealthy. Too little or too much of any one nutrient can cause problems. The main objective of the present study is to find out the best pH value of water to increase the quality of Echinodorus bleheri. Methodology This experiment was conducted under green house condition with 80% shade at Ruvini Aqua plants Lanka (pvt) Ltd, Koralawella, Moratuwa. Hundred and eighty Echinodorus bleheri plant pots(containing four plants in each pot) were used for the experiment. Experimental design was Complete Randomized Design. Fifteen Styrofoam boxes (46 cm×39.5 cm×19.5 cm) were used to plant them. HANNA (HI98107) portable digital pH meter was used to measure pH and HANNA portable digital EC meter (HI 98303) was used to measure Electrical Conductivity of water. Two months aged 180 Echinodorus bleheri plant pots were randomly selected and uprooted from culture tanks. Plant pots were washed thoroughly after removing sand and other objects. Randomly selected 12 plant pots were assigned in to a tank and measure the wet weight of 12 plant pots. Plant pots were planted in 15 Styrofoam boxes. Bottoms of the Styrofoam boxes were covered by black polythene sheets to prevent the algal growth. Placement of Styrofoam boxes were decided by lottery method. Five different pH solutions were used for the experiment as 6.0, 6.5, 7.0 (control), 7.5 and 8.0. Six grams of Albert solution was dissolved in 7 l of water and filtered the solution using a muslin cloth. pH of the solution was measured. NaOH or HCl was added drop wise until required pH value achieved and maintained the electrical conductivity 1000-1500 µs level. Prepared pH solutions were kept for 1 hour to see the fluctuations. pH solutions were poured in to tanks. After 2 days pH solutions of each tank were removed using manual squeeze water changer pump and filled the solutions again week, plant pots were uprooted from Styrofoam boxes and measured the wet weight of each replicate (12 plant pots). Total lengths of plants were measured using a tape weekly. Number of leaves was counted weekly. Wet weight of each replicate (12 plant pots) was measured before starting the experiment and at the end of the experiment. Data obtained from the experiment were analyzed by Microsoft Word. Treatment significances and significance among individual treatment levels were analyzed using one way analysis of variance (ANOVA).
Effect of selected organic sources on growth and yield of different maize (Zea mays L.) varieties in sandy regosol of Batticaloa district
(Uva Wellassa University of Sri Lanka, 2013) Sutharsan, S.; Srikrishnah, S.
The increased cost and ill effects on the environment and human being by using inorganic fertilizers have directed attention towards the use of organic manures, recently. Demand for organic agricultural products is rising in Sri Lanka due to attitude change of the people on health and environmental aspects. The increased demand for organically grown products urges scientists to disseminate knowledge to farmers. Maize is a popular coarse grain crop in Sri Lanka, grown in the second highest extent of land next to rice. Maize has a demand in foreign countries as it is used as a raw material in various industries. There is an increasing demand for exporting organically grown products including maize in Sri Lanka. In this situation, organically produced maize would gain more attraction from foreign consumers. Organic manures such as compost, cowdung etc. provides many advantages; improving soil tilth, aeration, water holding capacity and stimulating microorganisms in the soil that makes nutrients readily available (Lal, 1997) for plant absorption. However, there seems to be little use of organic manures island wide, and there is lack of knowledge on the effect of different manures on crop production. More information in relation to the use of organic manures is needed to educate the farmers. Hence, this research was carried out to evaluate the effects selected organic sources on growth and yield of maize varieties in sandy regosols of Batticaloa district and to select best manure for organic maize cultivation.
Determination of Shell Charcoal Yield of Different Coconut Varieties in Sri Lanka Under Optimum Temperature Condition
(Uva Wellassa University of Sri Lanka, 2013) Perera, W.N.U.; Herath, H.M.S.K.; Asanka, J.R.K.
Due to improper management, inefficient use of resources, low quality inputs and production procedures, charcoal production in Sri Lanka has become a less profitable industry, which pollutes the environment while causing health problems to the workers as well as to society. In Sri Lanka, charcoal is mainly produce using traditional methods. Therefore, the efficiency of these methods and quality of the charcoal produces are low compared to modern-improved technologies. As a developing country, it is difficult to adopt these improved methodologies due to lack of capital and other facilities. The study was carried out to determine (i) Optimum temperature condition for carbonization of Coconut shells and, (ii) the variety that gives the highest charcoal yield. Methodology To determination of optimum carbonization temperature, Coconut shells were oven dried for two days at 70 C, crushed and passed through 5mm sieve. Samples were weighed and placed in a muffle furnace at carbonization temperatures of 200,250, 300,350,400,450,500,550 C for different resident time periods 5, 10, 15,20,25,30 minutes respectively. The charcoal yield was weight in each occasion. Quality parameters such as volatile matter, ash content, moisture content and fixed carbon content of the charcoal was determined. The temperature and time, at which to weight charcoal yield with best quality produced were taken as the Optimum temperature and time. Which referred to the one, which gave the highest amount of charcoal with particular quality parameters (moisture content, ash content and volatile matter content) under optimum carbonization conditions.
Development of a Flavored Jelly Incorporated with Green Tea Extract
(Uva Wellassa University of Sri Lanka, 2013) Sirisena, A.M.N.T.; Alakolanga, A.G.A.W.; Herath, H.M.S.K.; Wickramage, C.P.
Tea (Camelia sinensis) is considered as one of the most popular non-alcoholic, non-carbonated beverage all over the world. It is rich with phenolic compounds, which have more health benefits. Green tea showed a higher polyphenol content than black tea (Anesini et al., 2008). A cup of green tea (2.5 g of green tea leaves/200 ml water) may contain 90 mg of Epigallocatechin Gallate (Cabrera et al., 2006). At present, only 21% of the world tea market belongs to Sri Lanka however Sri Lankan tea industry produces 40 – 45 % of value added tea products from the total tea exports (Herath and Silva, 2011). Development of ready-to-use product by incorporating tea creates an additional value to the primary product of tea and it will attract more consumers towards. The objectives of this study were to develop a ready to serve jelly by incorporating green tea extract, and to determine total amount of polyphenol in the product, appropriate proportion of the ingredients, and the shelf life of the product. Methodology The research was conducted as three experiments. In experiment 1, the suitable jelling time and temperature combination were identified. The formulated sample was subjected for three levels of time and temperature combinations. To obtain proper texture for setting of green tea jelly, the mixture was heated up to the range of 100 – 110 C for about 5 to 10 minutes. In experiment 2, by changing the green tea extract level (0, 1, 2 and 3%), suitable amount that should be incorporated to the product was identified by seven trained evaluators. Their responses were obtained under taste, aroma, texture, color and overall acceptability parameters. Pectin, sugar, water, permitted chemicals (citric acid, ascorbic acid, sodium benzoate) and green tea extract were used as the main ingredients. In the third experiment, Apple flavor was used and by changing the flavor strength, the suitable flavor level for the product was identified. The developed flavored jelly was evaluated for taste, aroma, mouth feel and overall acceptability, using thirty non-trained evaluators. The data of the both sensory evaluations were collected through sensory ballots and their responses were obtained in five point hedonic scale. Identification of yeast and moulds, E’coli / Coliform and aerobic plate count were done in order to evaluate quality of the product and determine the shelf life of the final product samples during ten weeks of storage period under both ambient and refrigerator conditions. The media solutions were prepared according to the Sri Lankan Standards 516 in 1991. Changes in pH value and dissolved solid content of final product were determined to identify the stability of the product. As the chemical requirements of the jelly, determination of moisture, acid insoluble ash and pectin content were carried out according to the Sri Lankan Standards 585: part 5 in 1994. The polyphenol content was determined by following ISO 14502-1:2005. The cost analysis of the product was calculated by considering the expenses made for the ingredients and packing materials. The data were analyzed by Kruskal-Wallis test (non parametric) with 95 % confidence level. To select the best treatment combination, mean separation was done by Conover-Inman method (Conover, 1999). Results were analyzed through MINITAB 15 and graphical methods were used to interpret the results.
Effect of Salicylic Acid and Benzothiadiazole on Control of Tea Blister Blight
(Uva Wellassa University of Sri Lanka, 2013) Nuwani, W.W.S.; Chandrasena, G.; Sinniah, G. D.
Blister blight caused by the obligate parasitic fungus Exobasidium vexans Massee is seriously affects the production by reducing quality and the quantity. Control of blister blight heavily depends on synthetic fungicides. Large-scale application of pesticides pollutes the environment and their residues can cause various health hazards to human beings. Therefore, use of environmentally friendly chemical in disease control strategies is gaining importance. Elicitors are low toxic chemicals that can be integrated into blister blight disease management. The objective of this study was to determine effect of Salicylic acid (SA) and 2, 1, 3- Benzothadiozole (BTH) on control of tea blister blight diseased caused by E. vexans Massee. Methodology TRI 2024, a susceptible cultivar to blister blight was treated with 1000 ppm SA, 1000 ppm BTH, 0.1% Copper hydroxide (Champ DP 37.5%), 0.05% Hexaconazole and untreated control at seven day intervals for four weeks under field conditions. The experimental design was Randomized Complete Block Design with four replicates in each treatment. leaves was assessed seven days after application of the chemicals. Harvestable shoots were collected separately from each plot and 100 shoots were selected randomly for each plot and assessed for Blister blight severity using a Blister assessment key where 0= No translucent spots, 1= Hypersensitive reaction (HR), 2= Blister >5% of total leaf area, if only translucent spots appear it covers 2-15% leaf area, 3= Blister cover >5% of total leaf area, if only translucent spots appear it covers 2-15% leaf area, 4= Blister cover 5-15% total leaf area, if only translucent spots appear, it covers >15% leaf area, 5= Blister cover 15 -30% of leaf area, 6= Blisters cover >30 leaf area and stem is infected. Disease severity was calculated according to the following formula:
Effect of Long Term Phosphorus Fertilizer Application on Phosphorus Availability and Cd Accumulation in Rice Soils (Oryza sativa L.)
(Uva Wellassa University of Sri Lanka, 2013) Dasanayaka, I.G.C.R.; Herath, H.M.S.K.; Sirisena, D.N.
Rice occupies approximately 33 % of the total cultivated area in Sri Lanka accounting to 0.78 million hectares (Central Bank of Sri Lanka, 2010). Plant nutrients are essential for the production of crops and in term of healthy food for the world’s increasing population. In that context, phosphorus (P) is an important nutrient in rice cultivation. P is directly absorbed form soil and makes up 0.1% - 0.4% of the dry matter in plants. It involves in carbohydrate breakdown for energy release, cell division and transfer of inherited characters. P stimulates early root growth and development, hastens maturity of plant, improves seed production and involves in energy transformation. Since supply of P from soil is not enough to obtain higher grain yields, farmers are advised to apply P fertilizer into soil. These synthetic fertilizers carry lot of heavy metals such as Cd as contaminants. Scientists are of great interest at the moment of the contamination of heavy metals to paddy fields through P fertilizer especially super phosphate (TSP). Cadmium (Cd) is a toxic heavy metal and is also known as one of the major environmental pollutants. Cd is dissolved in water, taken by crops, transferred to human body by ingestion causing health problems. This research was conducted to study the effect of P fertilizer application in the long term basis on soil fertility status and grain yield of paddy. Methodology The study was conducted at Rice Research and Development Institute Batalagoda situated in the low country intermediate zone IL1 agro ecological region of Sri Lanka (longitudes of 800 and 810 and latitude of 70 and 80 at an elevation of 65 meters above sea level). Soils of the experimental site belong to Kurunagala soil series and great soil group of Psummentichupludult. Treatments namely: no P fertilizer (T1); seasonal P fertilizer application (T2); alternative seasonal P application (T3) were used and arranged in Randomized Complete Block Design (RCBD) with four replicates. P fertilizer rates added to the above experiment were based on the recommendation given by the Department of Agriculture (Department of Agriculture, 2001). respectively. Soil samples were analyzed for available P and total P contents. Plant samples were analyzed for plant P contents. To determine Cd accumulation in soil, straw, seeds, plant and soil samples were analyzed. Having air dried and passed through 2 mm sieve, each sample was thoroughly ground into fine powder and total P, available P and Cd were measured.
Effect of Biochar Application on pH and pH Buffering Capacity of Rubber Growing Soils
(Uva Wellassa University of Sri Lanka, 2013) Rathanayaka, R.A.G.S.; Herath, H.M.S.K.; Dharmakeerthi, R.S.
Rubber (Heveabrasiliensis L.Muell. Arg.) growing soils in Sri Lanka are less fertile and characterized by low cation exchange capacity (CEC), very high acidity, and low organic carbon (OC). This has resulted low fertilizer use efficiency and low productivity in rubber growing soils. In order to increase soil fertility effectively, amending these soils with biochar (BC) are being evaluated (Dharmakeerthi et al., 2012). Biochar, is a solid material produced from pyrolysis of biomass, is a highly alkaline material with high CEC and higher percentage of stable OC (Sohi et al., 2010). Amending soils with BC may change soil pH and pH buffering capacities (Xu et al., 2012). However, there is no data available on changes of soil pH after BC addition in rubber growing soils not only in Sri Lanka, but also anywhere else in the world. Therefore, this study was conducted to investigate the effect of rubberwood BC on pH and pH buffering capacity of some contrasting rubber growing soilsin Sri Lanka. Methodology Two soils from traditional rubber growing areas i.e. Red Yellow Podsol (RYP) from Paiyagala Estate, Dodangoda, Reddish Brown Latasol (RBL) from Parambe Estate, Parambe, and one soil from dry zone, Reddish Brown Earth (RBE) from Thanamalwila ,representing contrasting agro - ecological conditions were selected for the study. Those soils were mixed with BC made from rubber wood with two different rates, 0 and 2% by weight andincubated at 70% water holding capacity at room temperature 25±2ºC for 12 weeks. The change in pH was measured at 0, 1, 4, and 12 weeks after the biochar amendment. pH buffering capacity was measured in another set of amended soils, incubated for 40 days as above, using the methods given by Liyanage et al. (2012) with certain modifications. All treatments were replicated four times. Results and Discussion Application of biochar increased pH in all three soils; the increase was very small in Thanamalwila soil while the greatest observed in Payagala soil. Week after incubation, the pH increase in the three soils were 0.4, 0.9 and 0.9 for Tanamalwila, Parambe and Payagala soils, respectively (Figure 1). As incubation time increased from 1 to 12 weeks, the pH did not increase significantly (p<0.05) in Thanamalwila and Payagala soils, and the gap decreased in significantly (p<0.05) Parambe soils. types. Thanamalwila soil had the highest pH buffer capacity (7.3mmol/kgpH) while Payagala soil had the lowest value (4.7mmol/kgpH) Parambe soil had (5.5mmol/kgpH) in between value. The pH buffering capacity was highly significantly correlated with CEC of the soils ( R =0.92 ,p< 0.001), indicating that CEC was an important factor determining soil pH buffering capacity.
Development of Nutrient Rich Value Added Instant Soup using Coconut Flour and Red Rice Flake
(Uva Wellassa University of Sri Lanka, 2013) Gunasinghe, R.D.M.S.; Gunadasa, H.K.S.G.; Abesinghe, A.M.C.S.
Dry instant soup mixes are one of the food items, which cater to the busy life style of the people and it is an easy way of providing nutrients across the world. The coconut (Cocos nucifera L.) is the most extensively grown and used nut in the world. Coconut is the one of major exporting crops in Sri Lanka. There are number of product made out of using various parts of coconut tree. Among these products, kernel based products plays major role as food items. Coconut flour is a latest popular by product and highly nutritional material since it rich with higher amount of dietary fiber, protein and some minerals. Red rice also contains numerous heath benefits than white rice. The main objective of this research was to develop nutrient rich value added instant soup using coconut flour and red rice flake. Research was conducted as three experiments. In experiment 1, best spices and other ingredient mixture and suitable amounts were selected. Five treatments were taken with different level of ingredients and different types. In experiment 2, best combination of coconut flour and red rice flake amounts were selected. Five treatments were taken by changing the coconut flour and red rice flake amount. Sensory data were analyzed according to Friedman test at 5% level of significance. In experiment 3, shelf life evaluation was practiced. Chemical composition analysis was conducted to evaluate nutrient value of the product. On the basis of the result the sample which is used 25% Coconut Flour and 12.5% Red Rice Flake has been selected as the best ratio for final soup mixture. The instant soup has higher nutrient value with reference to the local market dry soup mix and it can be concluded that the product has one month of shelf life on the basis of shelf life analysis result.
Partial Replacement of Beef Heart with Druckweed (Lemna minor) for Ornamental Carp (Cyprinus carpio)
(Uva Wellassa University of Sri Lanka, 2013) Jayarathne, G.L.U.C.; Jayamanne, S.C.; Bambaranda, M.; Bandaranayake, L.D.R.
Koi (Carp) is an ornamental fish variety belongs to family Cyprinidae. Beef heart is used as a good source of protein for fish. Since the cost of beef heart is high, formulation of fis h feed using an alternative protein source is important to reduce the cost of fish feed. Duckweed was used as the alternative source for beef at the present study. Main objectives of the study were to determine the optimum inclusion level and examine the growth performance of koi fingerlings that are very important for the ornamental fish industry.The experimental system was consisted of 18 rectangular glass tanks as having three replicates for each treatment. Ten fish were stocked in each tank (average weight 1.17±0.01 g and average length 3.3±0.05 cm). Lemna minor (duckweed) was collected and sun dried for two days and finely ground. Beef heart, duckweed, rice bran and wheat flour were used as feed ingredients. Vitamin and mineral were equally fixed as 0.5 % by weight for each six diets. Six different diets were formulated by following the Pearson square method with inclusion of different levels of duckweed 0 %, 10 %, 20 %, 30 %, 40 %, and 50 % (Named as Diet 1,2,3,4,5 and 6 respectively). Dietary protein level of diets was estimated as 35 %. The amount of feed offered was 5 % body weight of fish. Daily feed allowance was twice a day. Weight and standard length of all fish were measured weekly intervals for seven weeks. Water quality parameters (Temperature, pH and Dissolved oxygen) were recorded and maintained throughout the experimental period. Percentage survival rate, Mean Weight Gain (MWG), Specific Growth Rate (SGR), Food Conversion Ratio (FCR), Protein Efficiency Ratio (PER) were calculated using standard methods. Data were analyzed using one-way Analysis of Variance (ANOVA). According to the mean values of growth parameters of fish fed with six different diets, the best values were recorded for diet 2 replacing beef heart with 10 % duckweed leaf meal. There was a significantly difference among mean ), FCR and PER values of six different diets (P<0.05MWG and SGR recorded for fish fed with diet 2, 3, 4 and 5 were not significantly different ) and the best FCR value was recorded for fish fed with diet 2. PER value of fish fed with control diet did not show a significant difference from that of other diets. There was a significantly difference (P > 0.05) among PER values of fish fed with diet 2 from that of other diets except from the control diet. There was no significantly difference (P > 0.05) in any of the water quality parameters in relation to different diets. Average water temperature was ranged between 29.61 °C to 29.66 °C while dissolved oxygen content was fluctuated from 6.35 ppm to 6.50 ppm. pH was ranged between 7.04 ppm to 7.09 ppm. This study showed that the use of Lemna minor leaf meal is suitable to partially replace very expensive beef heart for the growth of koi fingerlings. Low level of inclusion (10 %) of duckweed was the most efficient.
Development of Dates (Phoenix dactylifera) Incorporated Probiotic Ice Cream
(Uva Wellassa University of Sri Lanka, 2013) Gunawardena, S.N.P.; Abesinghe, A.M.N.L.; De Silva, K.I.U.
Ice creams are considered as sweetened frozen confectionaries. Today ice creams are modified as functional foods such as probiotic ice cream, low fat ice cream and ice creams with low sugar which deliver the nutritional and medicinal value to the consumer. However, ice cream that is enriched with nutritional and medicinal properties is rarely found in Sri Lankan food industry. Therefore, this study was conducted to fill the gap in Sri Lankan food industry by replacing the cane sugar in ice cream with Dates (Phoenix dactylifera) and by incorporating Lactobacillus acidophilus (LA-5 , CHR Hanson, Denmark) as the probiotic bacteria. Date fruits (Phoenix dactylifera) were incorporated in premium quality dairy ice cream as Cane sugar substitute with the aim of enriching the product with nutritional and medicinal values of Dates. Dates are having total sugar content of 60 -70 g/ 100 g with higher amount of fructose (Anne et al., 2005). Fructose is known as high intensity sweetener (1.7 sweetening power compared to sucrose) with lower glycemic index (Batia et al., 2008). Dates are rich with dietary fiber, vitamin A, B 1, B2, C, iron, potassium, calcium and polyphenols (FAO, 1993). Furthermore, Lactobacillus acidophilus is considered as a probiotic starter culture which confers many health benefits to the consumers by enhancing the microbial balance of the gastro-intestinal tract. Therefore, this study was carried out to develop a Dates incorporated probiotic ice cream. Methodology Research was carried out at Ceylon Cold Stores PLC (CCS), Ranala, Kaduwela. Laboratory analyses were done at CCS and Uva Wellassa University laboratories. Initially, the basic composition of the ice cream was determined. Three preliminary studies were performed to develop the structure of the ice cream as; selecting the best form and level of Dates incorporated in to ice cream and selecting the best level of fat and stabilizer/emulsifier. Three types of Dates were tested as Date pulp, powdered Dates and commercial Date syrup. Best combination of Dates and sugar for ice cream was determined by combining those in different combinations within the range of 13.3% and 28.52%. The best combination was selected by a sensory evaluation using seven trained panelists. After the preparation of ice cream with appropriate texture, two types of flavours; Date flavour (Akras AU 16668) and Rum flavour (Aromco NN15020)were incorporated in to Dates ice cream. Sensory evaluation was conducted to select the most preferred type of flavour in Dates incorporated ice cream. Selected ice cream was used to develop probiotic Dates ice cream by incorporating Lactobacillus acidophilus culture according to the method described by Hekmat and McMahon, 1992. Probiotic culture was incorporated in to ice cream after ageing and heat treatment. Ice cream was aged at 4 C for overnight. Then aged mix was subjected to heat treatment at 82 ºC for 30 seconds and allowed for cooling to 40 ºC. Then it was inoculated with 5-6 granules of freeze C for five hours in incubator. Incubated mix was then subjected for cooling process. When the temperature of the mix decreased to 4 C, it was beaten until desired overrun was achieved. Finally, ice cream was filled into containers and hardened at -18 ºC. Total viable cell count of Lactobacillus acidophilus was determined to find out the survival rate under -18 C using MRS agar (CM 0361, Oxoid Ltd, Hampshire, UK). Then, probiotic incorporated Dates ice cream and Date ice creams without probiotics were subjected to a sensory evaluation using seven trained panelists. Selected type of Dates ice cream was further analyzed for its physicochemical properties and microbiological quality. Proximate composition of the final product was analyzed for fat, total solids, moisture content, crude protein, and ash. Furthermore, Milk Solid Non Fat (MSNF), Brix and pH were measured. Microbiological analysis was done for Escherichia coli, Aerobic Plate Count (APC), Yeast and Mold. Date pulp was analyzed for physiochemical properties and microbiological quality. Melting rate for Dates ice creams were determined and the effect of percentage of Dates and percentage of stabilizer/emulsifier on melting rate were analyzed. Sensory data were analyzed according to the Friedman test using MINITAB 14 software package. Data obtained from melting tests were analyzed by analysis of variance (ANOVA) using SAS 9.1 software package. Complete Randomized Design was conducted for analysis at p˂ 0.005 level of significance.
Determination of Selective Chemical Quality Parameters of Commercial Tea Blends
(Uva Wellassa University of Sri Lanka, 2013) Wijebandara, L.R.S.P.; Bandara, S.M.I.P.G.; Herath, H.M.S.K.; Liyanage, A.
Tea (Camellia sinensis L.) is the second most widely consumed popular non-alcoholic beverage in the world for centuries due to its sensory attributes and health promoting effects. About 3x10 kg of various teas is consumed every year as a whole (Lu et al., 2004). Commercially, tea is used in blends combining several grades originated from different elevations and agro-climatic conditions. Those are distributed around the country through the auction and other meansunder different estate marks. This study was an effort to add more information on chemical quality of commercial tea blends by evaluating selected chemical quality parameters and comparing those with selected parallel products available in Australian market under different brands. Methodology The current study was carried out at Ceylon Tea Services PLC (CTS), Paliyagoda. Laboratory analysis was done at SLAB accredited chemical laboratory of Food Technology Department at CTS. Thirteen types of company standard green tea and black tea blends were evaluated.Total polyphenol content, caffeine content, moisture content of tea blends and pH, total soluble solid content, colour intensity of the brew were measured for 8 black tea blends 2 local green tea blends and 3 imported green tea blends. Chemical quality parameters were compared with 5 different tea brands under 5 different product categories. Five competitor samples (Twinings, Woolworth, Lipton, Abeya and Madura) which represent the leading brands in international tea market were compared with selective tea standards using chemical quality parameters. Those different tea blends which were used to produce different teas were considered as treatments. Total polyphenol content was determined according to the International Organization for Standardization method (ISO) 14502-1. Caffeine determination was based on Jenway Bibby Scientific (Application note: A09-010A). Moisture content (loss in mass at 103 °C) was determined on a portion of test sample in accordance with ISO 1572:1980 for leaf tea. The value for total soluble solids (TSS) of brew was measured using a refractometer(Atago, Japan) at 20°C (Borse et al., 2012).The color intensity of the tea brew was measured using a spectrophotometer at 450 nm (Halligudi et al., 2012). pH value of tea brew was measured using a pH meter (Cyberscan, Japan) at 25 C (Halligudi et al., 2012).Data were analyzed using the statistical procedure of one way analysis of variance (ANOVA) at 5 % level of significance and mean comparison was done using Tukey test at 95 % confidence interval using Minitab 16 statistical software.
Smart Shopping Application for Android Users
(Uva Wellassa University of Sri Lanka, 2013) Pilapitiya, H.M.O.A.; Sabani, M.J.A.
With the development of the technology, most of the people tend to use electrical items for their day to day activities. Mobile phone is the most popular electrical item among them. Most of the people use smart phones now. On the other hand shopping has become an intrinsic part of everyday life. With the advent of the mobile phone era and the frequent use of mobile apps to perform everyday tasks, the trend to use apps for creating and managing shopping lists is becoming more popular by the day. The purpose of creating price comparison application is to efficiently manage time and money while shopping. This application includes electrical items like mobile phones, Televisions, laptops, etc. By using this application users can identify the lowest price providers in Sri Lanka for the selected item and information about them. Methodology This application basically related with mobile application development with web services (Code on cloud, 2013). The development of the application was started with the UI designing. Eclipse Android Development Tool Kit (ADT) was used to design the application interfaces. The Jellybean was used as the android version, sdk and Samsung galaxy and android virtual devices (AVDs) as the testing devices. Android API level was 2.2 to 4.2. For the data mining purpose, some websites which are publishing electrical items’ prices and detail were selected. Using PHP and cURL library, data were extracted from those selected websites. DOM Document and xpath helped to find the location where the details were located. It was sent XML type data. The methods trim and slice were used to find correct values. Then it was converted into the JSON arrays. Those data were stored and hosted by using the 000webhostingfree webhosting. When user requested data, through the web services, it was parsing to the android application. AsyncTask was used to fetch data from web service. Application was decoded the JSON data and displayed on the User interface. It was tested several times to find bugs and was fixed the bugs found during the test phase. Figure 1 depicts the simple architecture of the application with all the modules described above. Result and Discussion It was easy to use eclipse ADT bundle to develop android applications. The emulator provided different types of virtual devices to test application. However, the actual devices run time period speed was faster than the emulator. cURL library and PHP was very useful for web mining processes. Using xpath it can easily be identified the correct path to the value. Sometime it was difficult to fetch data as most of the websites use their own structure. According to above designs, web services were developed even though it was difficult to handle. Conclusions Here prototype of the application has been developed. It was successfully fetched data from websites and displayed on android application. With that, anyone can engage with the dealers and develop the application for them. Then easily we can update the data and can maintain the updated information. It will help the user to get correct decisions when buying electrical items.
Robotic Frog
(Uva Wellassa University of Sri Lanka, 2013) Wijeratne, Y.M.J.U.; Wijesooriya, P.N.; Ekanayake, R.M.T.C.B.
All jumping involves the application of force against a substrate, which in turn generates a reactive force that propels the jumper away from the substrate (Willoms, 2006; Armour et al., 2007). Any solid or liquid capable of producing an opposing force can serve as a substrate, including ground or water. Examples of the latter include dolphins performing traveling jumps, and Indian skitter frogs executing standing jumps from water (D.E. Koditschek. and M. Bühler, 1991; Willoms, 2006). There are several types of projects done before in amphibious robotics for imitate animal’s locomotive mechanisms, behaviors in different environments, imitate their sounds (Saito et al., 1994; Willoms, 2006). In this project it is focused to imitate the mechanism of frog which use for their locomotion. Methodology To control the servo in 360 degrees, gears of the servo were modified because in normal conditions, they do not allow more than 180 degrees rotation. Then controlling circuit was prepared to give pulses to the servo for its rotation. Two NES 537 servo motors were used in this project. To modify the gear system, first the potentiometer was removed and a resister unit was added.

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