Report: Stella simulation
- 1. Course name: Information And Communication Technology In Science Course code: SSI3013 Practical report on: Systems Thinking for Education and Research (STELLA) Report Lecturer: Encik Azmi Bin Ibrahim Name Lecture Group Matric number Aimi Fatihah Bt Muhammad Fauzi B D20151071003 Najwa Husna Bt Saahwal B D20151070957 Siti Khadijah Binti Khalid B D20151070972 Nurul Najiha Husna binti Baharudin B D20151070960
- 2. 2 INTRODUCTION Referred to Oxford Dictionary, simulation has been defined as a model of a set of problems or events that can be used to teach someone how to do something or the process of making a model. Stella is one of the flexible computer simulations modelling package with an easy, intuitive interface that allows users to construct dynamic models that realistically simulate biological systems. STELLA is short for System Thinking, Experimental Learning Laboratory with Animation. It has been introduced by Barry Richmond in 1985. The program, distributed by isee systems which allow users to run models created a graphical representation of systems using four fundamental building blocks. It has been used in academia as a teaching tool and has been utilized in a variety of research and business applications. It is because of its simplicity relative to more complex modelling languages; STELLA has been cited as a useful tool in educational settings. The inventor viewed most of education as assimilating content and proposed system thinking as a remedy to this model. So, in 1987 High Performance Systems released a guide to STELLA encouraging its use in academic settings. Many textbooks have been published that teach modeling and system thinking using this software. There are some functionality and features of STELLA. It was complete package of modeling software that consist diagrams, charts, and uses animation help visual learners to discover relationships between variables and helps simplify model building. It also handles time series, sensitivity and simulation models well and has a drag and drop modeling interface. Users may create graphical models of a system using four fundamentals such as stocks, flows, converters and connectors. Relationships between converters (which convey transforming variables) and other elements may be drawn with converters. Users also are able to input value for stocks, flows and converters. In other hand, STELLA runs one window at a time meaning that only one model can be run at any given moment. The program’s native film formats are dnoted either by an .stm, .stmx, .itm or .itmx. STELLA also uses the emerging XML-based standard for storing models, XMILE. The languages run of Microsoft Windows and OS X and its most recent release was version
- 3. 3 10.1.2. in 2012, two researchers released StellaR, software which can translate STELLA models into the R programming language. DISCUSSION Graph 1 This Stella software provides the exploration of the model and conducts the experiments for all users. Stella is the best medium in education for instance, in order to enhance students’ motivation and their predictions on the results if they changed the variables by running the experiment themselves. So, the purpose of this attempt is to develop a model of a system that illustrates the effect of palm oil plant based on the population of owls and rats. There are few buttons that can be click in order to see how the simulation is functioning. The buttons are ‘run’, ‘stop’ and ‘pause’ and it also provides knob for students to manipulate the variables. All the buttons and the knob can be click and manipulate by students to see what will happen to the simulation graph. Exploring is an important element before students start to conduct any experiment as they will be more eager about the experiment and the important thing is they can relate the experiment with the theories they have learnt.
- 4. 4 For the beginning, students may set the knob that represents the number of rats and the number owls. According to the picture above, the user have set the left knob to 20000 that represents the population of rats and 12 on the right knob that represents the population of owls. After the variables has been set, students can click the ‘run’ button to see what kind of graph will the software produces. In addition, the software also provides the ‘slider’ for students to see how many fruits are harvests and also how many fruits are damages caused by the increasing of the rats in the plantations. According to the graph provided in the picture, it shows that the population of rats keep increases when there is a drop in population of owls. In the meanwhile, the production of palm oil still increase by years even the population of rats has increases for a few years. Here, students can noted that the increases of rats in the plantations give the big impact on the production of palm oil. So that, the population of owls plays an important role in order to increase the production of palm oil. The picture above is to demonstrate to the student on how to use this simulation and see the relationship among the variables on the graph. This simulation enables them to know how the scientists do their work every day. Moreover, this simulation can make the students to be more interested to conduct experiments after this, because they are able to manipulate the variables and see how the results produce.
- 5. 5 Graph 2 The knobs used in this simulation purposely to see the effect of owls’ population and rat populations towards the palm oil plants. This can be done by rotating the knobs to the left or right in order to adjust the number of populations for both owls and rats. In this graph, the rat population was set at 28000 while owls’ population is at 18. It can be compared with the first graph where the number of rats is at 20000 while the number of owls is at 12. So that we can see a very significant change between graph 1 and also graph 2. From the graph, we can see that the population of owls increases slightly at the beginning however after a few years, it started to decrease drastically to zero. The population of rats is very low at first while the number of palm oil plants production is slowly increasing throughout the year. However, after a few years the population of rats started to increase gradually because of there were no owls that acts as a predator to those rats. Therefore, the palm oil production was also started to decrease gradually. After another several years, the population of rats started to increase rapidly so it resulting in rapidly decreasing in number of palm oil plant because it cannot tolerate with the rat populations anymore.
- 6. 6 Based on this graph, the simulation shows the relationship of owls and rats population to the palm oil productions. We can see the significant change when there were increasing number of rats and decreasing number of owls in the production of palm oil plants. We can also conclude that there was equilibrium among these three variables. Thus, in order to cope with this situation, some biological methods can be implement for instance the biological control method where we can control the number of rats by increasing the number of owls in order to get a huge amount of palm oil production. Graph 3 Next, by using the stimulation student can generate data by prediction. The knob is used to manipulate the variable by increase or decrease the population of owl and rat to see the effect of the palm oil plant. Before that, the variables were manipulated which is both increasing the population of rat and owl. For the third picture, only the value of the owl population has been decrease. After changing the value of the owl population, the graph of the owl will slightly down and at the end will continuously constant. From the straight line graph also does not mean that no interaction is occurred but it can conclude as the condition stable. From the graph student can predict that the amount of owl increase the population of rat. Soon, the amount of rat will not reduce because from the manipulating variable by decreasing the population of owl, we found that there an excessive population of rat not being eaten. When we look at the pattern of the graph, the population of the rat pattern are closely related as it is inversely proportional to the population of oil palm plant’s pattern. The interaction is simple. The owl population act as a predator, so the variable has been manipulated by the student causes the outcomes of the oil palm plant population to be reduced. The oil palm plant is the main source. If not all the rat eat by the owl so it need more food supply. Then, the oil palm plant will reduce slowly.
- 7. 7 Furthermore, it shows that the population of rat will increase and also affected the source of oil palm plant to decrease too. From the pattern of graph, the students are able to predict the outcomes that happen for the next experiment if they know already what actually the pattern of the population of rat, population of owl that depends by the main source of oil palm plant. If the rate population of owl increase the rate population of rat decrease while if the rate of rat increase, the rate of owl will increase too. As this graph are not too complex to be interpreted by the students. It will trigger the student engagement towards these activities to be active. They will participate to formulate a new question and predict their own trend of outcomes for the next experiment. They can handle all the knowledge and transfer the knowledge to a new problems and situation that were given by the teachers.
- 8. 8 ADVANTAGES STELLA gives many advantages in teaching and learning process. One of the advantages is the teaching and learning process will become more interesting and exciting. It is because it helps students or learner to explore everything in various types of experiments. They also can enjoy the learning process and just not imagine on what have been taught by their teachers. Next, simulation software helps students to be more focus and extra knowledge to interpret data from the diagrams and graphs. Besides, in the same time it also helps to increase the level of curiosity among students and improve confidence between them and to put more effort on that experiment. Other than that, it also can help the teachers to teach the abstract content to the students. It is mean that, the simulation can make the student easy to understand as they can use the simulation and not just imagine on what have been taught by the teacher. Other advantages of using simulations are very quick development of complex models, short learning cycles and no programming is needed. So there will be minimal errors occurred. STELLA also helps to save the cost because teachers do not need to provide the apparatus and materials for the experiment. Just use the simulation software students can run out the experiment in a short time and students also will discover new things such as different hypothesis from the variables. STELLA also can be used in geosciences or medical field to investigate the effect of changes without producing a physical prototype. Besides, it also can be used to investigate situation that would be dangerous in real life. It also encourages students to inspire doing the experiment and helps passive students to be more active and involved in the experiment or the activity very well.
- 9. 9 DISADVANTAGES However, this simulation also gives disadvantages to the students that do not have computer or limited availability of computers. They will not have the opportunity to explore after they have learnt in class. Their learning process will happen only in the class. In addition, this simulation also can give a big problem to the users that do not know how to use computer. The users need to do two things in one time, which are learning about the computer and also learning about the simulation. So, may be the user will be lag behind the others. Besides, many simulations require intensive pre simulation lessons preparations. So, it takes time if students want to use the simulation in a short period. High cost of software also include as the disadvantages of the simulation. Only the trial one can be used by the users. But, after 30 days, it cannot be use anymore. In addition, limited scope of applicability and also limited flexibility. This is because the variation of the topics is not too many. Some of them may not fix with the users specific. Next, learn these simulations models also take time so it required additional training. As we know, not everyone has been good in IT skills. So, before use this simulations, users need spending more time to explore how to use this software before to use it. CONCLUSION Simulation is a suitable medium to be used in the school because it can motivate students in learning. Simulation motivate students by keeping them actively engaged in the deep learning process in order to solve the problems and make decisions to make the simulation run. As the simulation runs, it is modelling a dynamic system in which the learner is involved. Thus, participation in simulations enables students to engage in systems by thinking and enhances their understanding of the systems as well as the science concepts. Furthermore, students will become more exciting and inspiring in study because most of them like to do something rather than just hearing to something. However, finding a good simulation in teaching is quite challenging for teachers, but if the teachers know what their students need, it can be easier for the teachers.