Easy Java Simulations
About Easy Java Simulations
Easy Java Simulations, also known as EJS or Ejs, is an authoring tool written in Java that helps non-programmers create interactive simulations in Java, mainly for teaching or learning purposes. EJS has been created by [[1]] Francisco Esquembre and is part of the Open Source Physics project. File:EjsSplash.jpg
Rationale behind EJS
Simulations play an increasingly important role in the way we teach or do Science. This is especially true in Education, where computers are being used more and more as a way to make lectures more attractive to students, and to help them achieve a deeper understanding of the subject being taught.
However, it cannot be said that computer simulations are used by most of our teachers and educators. In many cases, this is due to the fact that teachers are reluctant to use a technology they do not fully understand or control. In other cases, it may be that they have not found a product that completely meets their educational needs.
A good solution to both of those points is to help teachers create their own simulations. We have found that, by creating a simulation, many teachers get a new perspective on the phenomenon they are trying to explain, which almost always increases their enthusiasm about the use of this technology for their students.
An alternative approach, which is also very promising, is to let students create their own simulations, thus engaging in what educational researchers call constructive modeling. This approach has the advantage of getting the student to do science in an exploratory and constructive way, which achieves many of the recommended best-practices in the classroom.
It is true that creating a simulation by oneself requires extra effort. The starting point, and this is the important part, is a full understanding of the phenomenon being simulated. From this, some technicalities are certainly needed in order to express the behavior of the phenomenon in a computer simulation.
Easy Java Simulations was written to address this problem. EJS has been specifically designed to teach a broad audience how to create scientific simulations in Java, in a quick and simple way.
The target audience for EJS is science students, teachers or researchers who have a basic knowledge of programming computers, but who cannot afford the big investment of time needed to create a complete graphical simulation. They are able to describe the models of phenomena of their respective disciplines in terms of equations or algorithms. But they still need an extra effort to create a sophisticated, interactive graphical user interface, in the style of simulations and software programs one can find nowadays in the Internet.
With this situation in mind, EJS has been designed to help a person who wants to create a simulation to concentrate most of his/her time in writing and refining the algorithms of the underlying scientific model (which is his/her real expertise), and to dedicate the minimum possible amount of time to the programming techniques. And yet obtain an independent, high performance, Internet-aware, final product.
The choice of Java as development language is justified in terms of its wide acceptance by the international Internet community, and the fact that it is supported under virtually all software platforms. This means that EJS, and the simulations created using it, can be used under virtually all different operating systems, and can also be distributed via the Internet and run within web pages by most (Java-enabled) web browsers.
What is EJS?
Easy Java Simulations is a software tool designed for the creation of discrete computer simulations.
A discrete computer simulation, or simply a computer simulation, is a computer program that tries to reproduce, for pedagogical or scientific purposes, a natural phenomenon through the visualization of the different states that it can have. Each of these states is described by a set of variables that change in time due to the iteration of a given algorithm.
All this means that EJS is a program that helps you create other programs; more precisely, to create scientific simulations.
There exist many programs that help create other programs. What makes EJS different from most other products is that EJS is not designed to make life easier for professional programmers, but has been conceived by science teachers, for science teachers and students. That is, for people who are more interested in the content of the simulation, the simulated phenomenon itself, and much less in the technical aspects needed to build the simulation.
Easy Java Simulations is a modeling and authoring tool expressly devoted to this task. It has been designed to let its user work at a high conceptual level, using a set a set of simplified tools, and concentrating most of his/her time on the scientific aspects of our simulation, asking the computer to automatically perform all the other necessary but easily automated tasks.
Nevertheless, the final result, which is automatically generated by EJS from your description, can, in terms of efficiency and sophistication, be taken as the creation of a professional programmer.
In particular, EJS creates Java applications that are platform independent, or applets that can be visualized using any Web browser (and therefore distributed through the Internet), which read data across the net, and which can be controlled using scripts from within web pages.
Because there is an educational value in the process of creating a simulation, EJS can also be used as a pedagogical tool itself. With it, teachers can ask their students to create a simulation by themselves, perhaps by following some guidelines which provided by the instructor. Used in this way, EJS can help students make their conceptualizations explicit. Used in groups, EJS can also improve the students abilities to discuss and communicate about science.
References
- W. Christian and F. Esquembre. Modeling Physics with Easy Java Simulations, The Physics Teacher, Nov. 2007.
- F. Esquembre. Creación de simulaciones interactivas en Java, Pearson Educación, 2004. (Book in Spanish)