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A Novel Web-Based Laboratory for DC Motor Experiments ILHAMI COLAK, SEVKI DEMIRBAS, SEREF SAGIROGLU, ERDAL IRMAK Gazi Electrical Machines and Energy Control (GEMEC) Group, Technical Education Faculty Electrical Education Department, Gazi University, 06500 Besevler/Ankara, Turkey Received 2 June 2008; accepted 27 October 2008 ABSTRACT: This article introduces a novel web-based DC motor laboratory, called NeTRe-LAB, to support teaching electrical machines. The NeTRe-LAB includes favorable animations to facilitate understanding characteristics of the DC motor, interactive DC motor models for instructive simulations, and web-based experiments with online monitoring features. To illustrate the current operations, remote access to an experimental setup of a DC motor has been provided and the speed control of it has been realized over Internet. The evaluation results have shown that the NeTRe-LAB presented in this study provides encouraging aspects, services, and support system for higher education. ß 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 19: 125 135, 2011; View this article online at wileyonlinelibrary.com; DOI 10.1002/cae.20298 Keywords: virtual laboratory; real-time experiment; DC motors; modeling; simulation

INTRODUCTION Web-based technologies support many learning activities in virtual and remote laboratories. In virtual labs, experiments are simulated and visualized by means of various software or packet programs having virtual toolboxes or components. Virtual labs allow clients to access continuously to simulation processes in remote servers. On the other hand, remote labs use real experimental setups. In a web-based real-time laboratory, all of the instrumentations used in the experiment are remotely accessed over the web, and the students can carry out the measurements in his or her own time while continuously refining the design as the measurements are being made [1,2]. Thus, students interact with real hardware units and observe real-time operation conditions. In this manner, education served over the web would be more interesting, existing, encouraging, and instructive. Nowadays, most of the schools in developed countries have web accesses and the adaptation of new technologies in education opens new horizons for developing of new technological infrastructures and techniques. However, educational applications are still limited with mainly asynchronous multimedia material, simulations, animations and presentations [3]. Recently, usage of the web-based laboratory in engineering education has been growing. A lot of examples on webbased laboratory can be found in literature. Some examples area applied for remote laboratories are chemical engineering [4], numerically controlled machining [5], torsion laboratory [6], and greenhouse scale model [7]. In addition, many electrical

Correspondence to I. Colak ([email protected].). ß 2009 Wiley Periodicals Inc.

machines laboratory applications have been studied by researchers such as study on the grid connection of a synchronous generator to the alternating current network [8], power system harmonic measurement [9], monitoring and controlling remotely of a three-phase squirrel cage induction motor mechanically coupled with a DC dynamometer [10], position control of a DC motor [11], a virtual instrument detecting spatial saliencies in induction machines [12], an internal distributed system linked by a data acquisition interface and a DC motor control module [13], a virtual laboratory improving the automatic control of interconnected tanks [14], integrated virtual learning system for the development of DSPbased control schemes for motor drive applications [15], a virtual laboratory for neuro-fuzzy control of induction motors [16], a prototype client-server system for remotely conducting experiments on brushless DC motors [17]. In this study, a novel web-based DC motor laboratory called NeTRe-LAB is presented. The NeTRe-LAB integrates all features of virtual and remote labs. The integrations cover theoretical information about DC motor, various animations embedded in theoretical information to simplify the learning, interactive simulations based on mathematical models of the DC motor, experimental setups accessible and executable remotely over the web to operate real-world experiments, and network cameras providing live information about experimental setup. The NeTRe-LAB also supports other standard components of the web-based distance education models such as member management system, forum, online chat, etc. Therefore, the NeTRe-LAB provides to students not only learning and using the latest technologies and concepts but also realizing, controlling, monitoring, recording, reprogramming, discussing and testing available applications or developed by themselves.

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Each of the studies summarized above [1 17] has used different software techniques to acquire the best solution for web-based laboratories. As compared the NeTRe-LAB presented in this study with other studies given in literature considering the software techniques, it differs from other studies due to mainly based on MATLAB web server (MWS). In engineering education, MATLAB is one of the software tools used by over 2,500 universities all over the world to support learning [18]. Although some considerable studies [18 24] based on MWS have been presented recently, an Internet based remote and virtual electrical machines laboratory including both simulations and real-world experiments based on MWS was not studied in detail. Additionally, most of the studies in literature about web-based electrical machines education concentrate on either simulation or real-time application. In contrast, the NeTRe-LAB keeps all features of both virtual and remote laboratories. Moreover, it includes other standard web components such as online chat and forum. Therefore, it could be considered that the NeTRe-LAB has a novel and fully integrated structure. The NeTRe-LAB was evaluated on more than 100 students. The results have shown that supporting actual experiments on web applications is really promising, multimedia support in exercises increases user’s motivation, performing DC motor exercises over the web environment is exciting, monitoring the response of the experimental setup directly is very attractive, and using up-to date technologies in learning is really encouraging.

SYSTEM ARCHITECTURE The main objective of this study is to develop an advanced learning laboratory for a DC motor that will allow students to operate real-world experiments on Internet. The NeTRe-LAB also serves additional features as theoretical presentations, favorable animations to facilitate understanding, effective interactive models for simulations, facilities for actual experiments accessible via Internet, monitoring experiments remotely with network cameras, and evaluation of learning via test exercises. The system architecture consists of hardware and software. These are explained in detail in the following sections.

special server started from a client, was especially used to run the simulations at the clients. Similarly, MATLAB Data Acquisition toolbox was used to get and send data from the experimental set as well as control operations over Internet. A block diagram of the system developed is given in Figure 1. As shown in Figure 1, Internet connection and Internet browser are enough to benefit from the web-based learning system. It needs to be emphasized that all operations were executed from the server. So, clients do not require any additional software or hardware in order to use the system. A common MATLAB m-file was prepared to perform tasks as given below: Transfer data and other commands sent by client to MATLAB environment. Create analog input (AI) or analog output (AO) objects and then add channels into these objects and set the configuration. Activate AO subsystem of the data acquisition board (DAQ board) using AO object. Receive data from AI subsystem of DAQ board and then transfer them to MATLAB environment by means of AI object. Convert operation results to appropriate format and send to clients. Prepare the content of HTML result page and then send it to clients. Clear all created objects and variables from MATLAB environment after completing the application.

Hardware Hardware structure of the NeTRe-LAB is shown in Figure 2. As seen in Figure 2, two servers, one for simulation and one for application have been used in the NeTRe-LAB to share and reduce the network traffic of the system. Thus, traffic of the servers and response time of the system are drastically decreased. While the application server serves the remote experimentation service, the simulation server includes all theoretical pages, animations, simulations and other web services. Furthermore, a DAQ board provides communication between the PC and the experimental setup.

EXPERIMENTAL STUDY Software The NeTRe-LAB platform has server/client architecture. Apache 2.0.48 server software was used to communicate with the clients. Apache is very popular server software and preferred commonly by webmasters all over the world because of its many useful features including open source code, independence of operating system, fast and safe communication. Likewise, MySQL 5.0 server software was used to keep and manage user information and to save data obtained from the experiments by the platform user. Basic PHP 4.0 techniques and HTML commands were used to prepare the presentation theory of DC motors. In addition, several animation programs were utilized to create animations inserted into the presentation. Web-based simulation models were developed in MATLAB environment. MWS toolbox, a web front-end tool to design MATLAB simulations and applications running on a

Interactive usage of the NeTRe-LAB and conducting experiments in general is followed as: 1. Access the web site via a browser. 2. Access the NeTRe-LAB using the registered info (see Fig. 1). 3. Once the authentication of a user is verified, the user can achieve any operation. 4. Select one of the desired experiments. 5. Use forum, online chat, etc. facilities if necessary. The NeTRe-LAB also supports web components if necessary via web-based platform. 6. Learn the details of experiments from theoretical documents. 7. Learn the details of experiments from animations having main characteristics and theory of DC motors.

WEB BASED LAB FOR DC MOTOR EXPERIMENTS

Figure 1

Software structure of the NeTRe-LAB.

Figure 2 Hardware structure of the NeTRe-LAB. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]

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Figure 3 Example for theoretical presentation supporting animation. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]

8. Learn more the theory of DC motors from interactive simulations. 9. Do and learn the experiences of real-time experimental studies of DC motors (detailed information and experimental procedure are given in Conducting Experiments Remotely Section). 10. Examine and evaluate the results carefully. 11. Compare, share and discuss the results achieved from simulations, animations and real experiments. 12. Go to (4) and open an HTML input page again to repeat the experiment using different parameters.

Theoretical Presentations With Animations The NeTRe-LAB has been designed to provide a new learning platform for DC motors in education. In order to achieve that, interactive web pages were prepared to enable information about DC motors. In addition, animations were developed to support and facilitate learning. An example theoretical presentation including animation support is illustrated in Figure 3.

Interactive Simulation Models In this study, web-based simulation models have been designed to analyze the transient and steady-state behaviors of DC motors under different parameters. Modeling and simulation of the electrical machines are quite important especially for using machines in real-time applications. It is required to develop a mathematical model of the system and to perform simulations on the models according to exercises realized considering the type of and the operation conditions. Thus so, problems that

might be occurred in real-world operations can be solved. In NeTRe-LAB, mathematical models are initially solved over the web using MATLAB. In this article, a PID controlled DC motor simulation was presented to demonstrate the web-based simulation applications. The behavior of the motor can be observed graphically by means of changing the motor and the PID parameters. Users only enter the parameters on web browser using HTML input page and click on the Submit button. The data just entered are then transmitted to the MWS toolbox through the Apache Server. The MWS executes related MATLAB script written. The script includes mathematical model of the system. The simulation is performed by MATLAB script according to the data submitted over web. Any number of users can connect to the system and can perform the simulation. However, even if it is not much considerable point, any increase in the number of the users connected to the system causes time delay in response time of the system is also increase. Therefore simulation system has option in order to restrict number of the users connected to the system. The simulation results are obtained first and the graphics generated are then sent to users. Figure 4a depicts the user interface screen which was used during on-line web-based simulation. The response of the system for the PID controlled DC motor simulation is given in Figure 4b. As can be seen in Figure 4b, the results are in a graphical form. A short explanation about the simulation results is also given on the browser page to express the operation more clearly. The explanations cover some hints and points considered for operations being performed. Thus, more instructive and remarkable simulations are done for real-time learners.


Figure 4 (a) Interactive simulation window for exercises. (b) Interactive simulation results. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]

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Conducting Experiments Remotely The NeTRe-LAB includes the real-time experimental sets which are remotely accessible via Internet. Speed control experiment of a DC motor using PI controller is given in this study as an example to illustrate the remote experiments. Users can remotely access to the set over the web to perform actual experiments such as speed control and generator operation of the motor. The experimental setup designed in this study is depicted in Figure 5. The set consists of two DC motors, a drive circuit and a low cost microcontroller. DC motors were coupled to each other, one was used as a motor and the other was used as a tachogenerator. A DAQ board and its expansion module were deployed to communicate the server and the experimental setup. Motor signals such as speed and input voltage were measured, and the reference speed was produced with the DAQ board. MATLAB software was used for processing data on the server. MWS toolbox was also selected for communication between server and client. Finally, two network cameras were mounted on the experimental setup to provide real-time views about current operations to the users. Another way of saying that the users can monitor the reaction of the motor system at a long distance. This experiment provides users to compare the users experiences achieved from the real-time experiments, simulations and animations. As shown in Figure 5, the test rig of the proposed system was installed in a special laboratory. Authorized persons can only access to this laboratory. If it is necessary to do some arrangements on the test rig, the system is first disconnected from Internet and the arrangements are then completed. Other precautions have to be taken as in classical approaches. In Figures 6 and 7, a DC motor experiment achieved on web browser is illustrated. As seen from Figure 7, students can perform a DC motor experiment only using Internet browser on the web page provided. Speed control of the motor based on PI controller can be achieved using a combo box available on the user interface given in Figure 6.

The simplified form of the operation steps are given below: Open the experimental setup (illustrated in Fig. 6). Select reference speed value for the motor using the related combo-box indicated as Wref on the HTML input page (see Fig. 6). Determine and enter a proportional gain indicated as Kp (see Fig. 6). Determine and enter an integral gain indicated as Ki (see Fig. 6). Set the operation times using Initial Time, Sampling Time, and Stop Time (see Fig. 6 again). Click on ‘‘Camera 1’’ and ‘‘Camera 2’’ buttons to monitor the experimental setup from two different angles (see Figs. 6 and 7). Click on ‘‘Submit’’ button to start the operation. Wait for 0.6 s for the process being performed by the server. Results will be displayed immediately after the process is completed successfully. The amount of time step required at millisecond level for doing all tasks such as measuring the speed data during transient and steady state operation depending on the user who can select period of the operation time to get transient or steady state data. Evaluate the results with other students. Test the systems with different control parameters if necessary. Learn the effects of parameters on the speed control by changing them in real-time. Save results by clicking the right mouse button and then selecting the ‘‘Save picture as’’ option (see Fig. 7). Discuss and compare all results including simulation, animation and experiment using online chat and forum pages using ‘‘Chat&Forum’’ button (see Fig. 3). As mentioned above, students only select the parameters for operation and click on the submit button to perform an

Figure 5 DC motor experimental setup for web-based real-time operation exercises. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]


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Figure 6 Monitoring and practicing real-time experiment via web browser. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]

actual experiment using the NeTRe-LAB. All operation steps for a real-time experiment are then automatically performed by the system as summarized above. It needs to be emphasized once more that the operation time for the processes were about milliseconds.

Figure 7 shows the graphical form of real-time operations for speed control experiment of DC motor. The speed versus time graphic of the motor according to the values inputted on web input page is generated as shown in Figure 7. Moreover, a table is also produced and given at the same page under the

Figure 7 Monitoring results via web-browser for real-time exercises. [Color figure can be viewed in the online issue, which is available at wileyonlinelibrary.com.]

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graphic. This table also covers the real-time data measured from the experimental setup during the operation. It is important to mention that clicking on ‘‘Submit’’ button establishes a connection between the client PC and the server. The data received from a client is transferred into the MATLAB environment by means of MWS. AO object of MATLAB DAQ toolbox is then activated. A signal is later generated by AO subsystem of DAQ board to start the operation of experimental setup. According to the data received from a client, the server produces a DC level control signal and applies it to the microcontroller. The microcontroller in the drive circuit of the DC motor generates a PWM signal based on the control signal. When a speed command is altered, pulse width varies; armature current and speed of the DC motor is then adjusted. The speed is measured by a tachogenerator coupled to the DC motor. The speed signal and the armature voltage are transferred to the analogue input subsystem of DAQ board. These measured values are then transferred into MATLAB environment by means of an AI object written in a MATLAB m-file. Additionally, the time information related to measured values is received from DAQ board and sent into the m-file. Rotor speed is calculated in the m-file using the generated output voltage values. Various figures are plotted by means of measured and calculated values on the web page. Finally, all of the values and figures are sent to the client. The NeTRe-LAB also includes a powerful error handling mechanism to protect the system from any damaged factor that makes the operation of the system unstable as following: Users may input any parameter as out of the limits. The experimental set may be in use from another user at the same time. The experimental set may be out of order due to a hardware problem. The system may be upgraded, etc.

Table 1

If any of the special conditions occurs as briefly mentioned above, a warning message is appeared in the window and users are informed about the problem by the server automatically.

STUDENT ASSESSMENT AND EVALUATION NeTRe-LAB was tested and evaluated on 109 undergraduate students. They are all third year students and attended to Electrical Machine Courses previously and performed the same experiment using the classical hands on method in laboratory. The questions asked to the students and their opinions for the system are given in Table 1. As can be seen from Table 1, the results are very encouraging and promising for web-based learning introduced in this study. The student opinions were evaluated as below: 1. Web-based educational tools are very attractive to be examined in new manners. 2. Using web-based educational tools in educations will make them to be aware of new challenges in learning. 3. Most of the students indicated that supporting learning with animations make the system attractive for comprehensible learning. 4. Although most of the students used a simulation of electrical machine for the first time, they mostly requested to do more simulation examples. From this point using interactive simulations is highly important to achieve effective learning. 5. The results of the evaluation were also pointed out that doing experiments in real-time web platform is also very important for better and faster learning and getting different experiences using recent web-based technologies to obtain the course goals.

Student Opinions About the NeTRe-LAB Student opinions

Opinions Performing this online experiment is quite impressive for me; therefore it can be repeated willingly again and again by the students Similar online experiments must be developed for other courses The application has ensured to self-confidence for students Animations used in presentations has facilitated to learning I have achieved the simulation of an electrical machine for the first time Number of real-time web-based courses must be increased Real-time experiment has facilitated to understand the course During the real-time experiment, I have felt myself as if I was in a real laboratory During the real-time experiment, I have concentrated more on the operation by means of observing the setup with cameras All questions in my mind about the experiment have replied This online experimental method is more safely than classical hands on experiments This online experiment is more instructive than hands on experiments This online experimental study has made me to feel more relax than classical hands on experiments It was a disadvantage of this online experiment that the wiring and connections for the set up were not done by me It was very important for me to see all possible faults during hands on experiments As independent from time and place, arbitrarily repeating the experiment again and again has facilitated to the learning process The system is more effectual than conventional laboratory systems

Fully agreed (%)

Partially agreed (%)

Disagreed (%)

84 85 64 85 68 61 64 40

11 9 18 12 6 17 32 34

3 6 18 3 26 22 4 26

76 55 72 40 68

16 20 20 30 18

8 25 8 30 14

37 45

34 35

29 20

82 41

11 38

7 21


6. Real-time remote laboratory exercises are more attractive than virtual laboratory ones for students. 7. Web-based experiments are perceived as more safe and more relax environment than the classical hands on experiments. 8. Especially, the most important opinion that was emphasized by the students is to perform experiments repeatedly as independent from time and place limitations. 9. The NeTRe-LAB allows students to improve their selflearning capabilities. 10. Performing the experiments without time restriction in classical hands on laboratories make them happy without any time pressure. Even if real-time experiments are limited, students can learn the electrical machines from animations, simulations and also recorded real-time experiments using web platform. 11. Most of the students indicated that monitoring experimental setup and real-time laboratory environment by cameras helped them to understand the experimental environment more concisely. It could be considered that using visual and sensual devices such as cameras and microphones are quite important for the web-based educational systems. 12. Since the NeTRe-LAB is a novel system and students have some habits that were acquired from the classical education system, they were not certain for some questions. Even so, the NeTRe-LAB was appreciated by all students and all of them were mostly happy and highly motivated to use and get benefit of the NeTRe-LAB. 13. Additionally, most of the students were willing to use such online applications not only for electrical machine exercises but also other courses as well.

Features and Benefits of the NeTRe-LAB The NeTRe-LAB has important superiorities in terms of pedagogical and technical aspects when it is compared to the conventional laboratories. Some of them are given below:

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Engineers and technicians may use the real-time experimental sets presented in the system for observing dynamic variations of systems. Life long learning (LLL) can be supported continuously according to the latest technological developments. New courses for LLL can be easily adapted to the system developed.

Drawbacks of the NeTRe-LAB Although encouraged feedbacks were obtained from the evaluation results, the NeTRe-LAB has some drawbacks and disadvantages in the present form of structure. These are: Slow response time depending on network speed and system requests: This disadvantage is valid for most of the web-based systems. However, to minimize this disadvantage in the NeTRe-LAB, the web pages including input and result interfaces for real-time experiments are designed simply as much as possible. Thus, the web pages are displayed more quickly. Only one user can connect to the web-based experimental system and performs the experiments at the same time. Therefore if the experimental system is used by one user others have to wait until the system is unemployed. Authors are in the effort of developing a considerable learning and management system (LMS) to minimize this disadvantage. When this LMS is completed, it can be possible to assign a pre-determined time for an experiment, thus, any user does not keep the experimental set busy, and other users will connect to the set within a short time. MWS requires a high performance CPU and considerable RAM on the server. 3D animations were programmed in several video formats in MATLAB. MWS supports these formats, but the response time of the system reaches up to 1 min when the 3D animations were used. However, the main motivation of this study is to achieve real-time experimental studies over the Internet. The NeTRe-LAB is primarily focused on real-time exercises.

CONCLUSION Risks in some experiments performed under hazardous conditions such as high electricity might be reduced. New opportunities make students more excited in learning real-time environments. Providing users or students learning equalization without time and place dependency. Selecting learning concept and level according to their choices. Improving self-learning abilities. Accessing all course materials instantly. Course contents can be updated easily according to the latest challenges in technology. Many institutions and universities may collectively use and profit from virtual and remote labs. Users can repeat their experimental studies easily again and again. The system developed might be easily an open laboratory. So, it can be used not only students, but also engineers, researchers, and technicians.

In this study, a novel web-based learning system called NeTReLAB for DC motors experiments was successfully presented to improve learning abilities of students and researchers in actual applications on the web. The proposed system also provides facilities to users who do not have opportunities to experience DC motor exercises in conventional laboratories. The NeTRe-LAB is an integrated system covering hardware, software and mechanics. The system designed was based on up-to-date technologies and enables to learn real-time courses on Internet including the theoretical presentations, favorable animations, web-based simulation models, and real-time exercises. So the system provides a learning platform to users to access to the system, to monitor the exercises, to see the result online and to facilitate standard web components such as online chat and forum, etc. In order to test the system, a DC motor course was prepared and an experimental setup was designed. Theoretical presentations for the DC motor were prepared and presented on

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PHP. All expressions were simplified and presented. Visual animations were also used inside the texts to ensure learning as easy and effective as possible. Additionally, instructive webbased simulation models were developed. Users can perform these simple and user-friendly simulations under different parameters and different control techniques to observe transient and steady-state behaviors of the motor. This might provide significant benefits to users to do their exercises without any time and place restriction. Finally, in order to show the impact of the study, a remote accessible DC motor experimental setup was also presented in this study. Data transmission between the server and the setup were achieved with a DAQ board. The DAQ board used in the NeTReLAB collects 500,000 data per second. Generally, it is not possible to acquire such sensitive measurements in conventional laboratories. All necessary processes such as remote access and control operation of the DAQ board were deployed via Internet. Generating graphics according to the data read from the board, receiving input settings and values from the web browser for the inputs, and sending results to the user browser were executed by a MATLAB script. Recently, 10 experiments have been performed using the NeTRe-LAB and all of these experiments were selected from the curriculum of the Electrical Education Department, Gazi University. However, only one experimental study was introduced in this study because of the page limitation. A webbased speed control of a DC motor using PI controller was given in this article to illustrate the structure of the NeTRe-LAB. Other than this, the authors conducted different experiments available in the curriculum with the NeTRe-LAB such as fourquadrant speed control of DC motor, loaded and unload test of induction motors and speed control of ultrasonic motor. Furthermore, NeTRe-LAB has currently been adapting to industrial applications such as analysis of harmonics, correction of power factor, automation of the solar and the wind energy systems over the web.

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BIOGRAPHIES Ilhami Colak was born in Turkey. He graduated from the Department of Electrical and Electronics Education of Gazi University in 1985. He received his Master of Science (MSc) Degree from the Institute of Science and Technology of Gazi University in 1988 and his Master of Philosophy (MPhil) Degree from the Department of Electrical and Electronics Engineering of Birmingham University in Birmingham, UK in 1991 and his Doctor of Philosophy (PhD) Degree from the Department of Electrical Engineering of Aston University in Birmingham, UK in 1994. He has been the Head of Power System Education Group of Gazi University since 1995. He was used to be a Founder Manager of Vocational School of Higher Education of Atatrk and Gazi of Gazi University, Turkey between 2002 and 2005. He became a full Professor at Gazi University in 2005 and is currently the Head of Electrical Education. His main research area covers electrical machines, power electronics, distance education, artificial neural networks, alternating energy sources and automatic control. He has published more than 85 referred scientific papers and 3 books. He has finished more than 11 Projects and supervised 6 PhD and 18 MSc students. He is a member of Institution of Electrical and Electronics Engineering Society (IEEE). Sevki Demirbas was born in Turkey. He graduated from the Department of Electrical Education of Gazi University in 1993. He received his Master of Science (MSc) in 1995 and his Doctor of Philosophy (PhD) Degree in 2001 from the Institute of Science and Technology of Gazi University, Turkey. He is currently an Assistance Professor at Department of Electrical Education at Faculty of Technical Education, Gazi University. His main research area covers electric drives, power electronics, simulation and modeling.

Seref Sagiroglu was born in Turkey. He received the BS degree in electronic engineering from Erciyes University, Kayseri, Turkey, in 1987, and the PhD degree in system engineering from the University of Wales College of Cardiff, UK, in 1994. He is now Professor at the Department of Computer Engineering and head of the department, Gazi University. His research interests include modern heuristic optimization techniques (genetic algorithms, tabu search, and simulated annealing), artificial neural networks, fuzzy logic, intelligent system identification, modeling and control, and robotics, computer and information security, webbased applications. Erdal Irmak was born in Turkey. He graduated from the Department of Electrical Education of Gazi University in 1997. He received his Master of Science (MSc) in 2001 and his Doctor of Philosophy (PhD) Degree in 2007 from the Institute of Science and Technology of Gazi University, Turkey. He is currently a lecturer at Department of Electrical Education at Faculty of Technical Education, Gazi University. His main research area covers virtual and remote laboratory applications, internet based distance education, web based control, simulation and modeling of electrical machines.