Title of the Paper (18pt Times New Roman, Bold)



Learning Object Model for Laboratory-based Lessons

HABIB MIR HOSSEINI, KECK-VOON LING, BING DUAN, ROBERT KHENG LENG GAY

School of Electrical and Electronic Engineering

Nanyang Technological University

SINGAPORE

Abstract: - There is considerable pressure on academic and educational institutes to improve accessibility and quality of the learning environments. Many have found the Web-based technologies as part of the solution. In a Web-based learning environment learners, which are often physically separated from teachers, can participate in the learning environment at their convenient time and location. Most of the existing e-Learning systems are designed for content-based subjects that deliver course content such as text, images, video, audio, and simulation to the student through the Internet. In this paper, we introduce a model for providing experimental and lab-based lessons over the Internet. In our study, we present the lab-based experiments as reusable Learning Objects (LO).

Key-Words: - Online Laboratory, Virtual Laboratory, e-learning, Reusable Learning Objects

1 Introduction

Wilson in [1] defines a learning environment as “a place where learners may work together and support each other as they use a variety of tools and information resources in their pursuit of learning goals and problem-solving activities”. Increasing popularity of the Internet has enormously transformed the educational practices. Technology supported learning environments are not exclusive to the World Wide Web. Online learning environments provide the students access to the course content at any time and from anywhere.

Providing laboratory-based experiments as an online service has been growing in popularity in recent years. Several online or remote laboratories have been developed [2-8] to bring the e-Learning concept to the lab-based courses. Numerous online or remote Laboratories have been used to supplement the traditional engineering courses with remote experiments. These systems, mainly web-based, allow students to conduct real lab experiment, as opposed to computer simulations, from anywhere and at any time. Cyberlab [2] is a typical example of such systems.

Learning Objects are discrete units of learning resources based on agreed standards. Learning Objects promote greater reuse of resources within new instructional systems development. The idea of the Learning Objects is inspired from the integration of reusable software components in software engineering [9]. The increasing interest in the educational potential of the Internet suggests moving to a component model for development of courses and content [10]. One important benefit of a component type approach is reusability. This means a component used on one system can be used to provide the same function for another system.

In this paper, we present our research on applying the learning concepts on online laboratory experiments. First, we review the idea of Learning Objects in section 2, and present some design considerations in section 3. In section 4, the proposed implementation of lab-based Learning Objects will be discussed followed by some implemented systems in section 5. Finally, in section 6, we present concluding remarks.

Learning Objects

Sometime in the mid 90’s the term “Learning Object” was introduced [11]. Many definitions have been provided for Learning Objects by different organizations and e-Learning technologists. However, the main point is to have learning material broken down into smaller pieces that could be later combined by instructors, learners and eventually computers into larger structures to support learning. One of the benefits of using Learning Objects as building blocks for an e-Learning environment is ability to personalize the environment and assemble the objects on the fly for every individual learner.

The main benefit of using Learning Objects is the capability of reuse. Issues such as cost, development time and learning effectiveness have persuaded a large number of learning technologists to support the use of Learning Objects.

A Learning Object consists of three components. The learning object itself that is the actual content (text, graphic, animation, etc), Metatagging, which describes the content, and a Learning Content Management System, which stores, tracks and delivers content.

Metatagging could be defined as describing and identifying the content of a document through the use of tags similar to HTML tags. The Metadata is used to describe and index the Learning Objects. This helps learners to seek and retrieve the specific material they are looking for from a repository.

Learning Content Management System includes two concepts: Learning Management System (LMS) and Content Management System (CMS). A LMS is used usually for administration of the learning program and the distribution of the content. It enables teachers to deliver, track, analyze, report, and assess on their students learning condition. It also helps students decide their learning path and communicate with their peers. A CMS, however, is used to create and administer online content.

Design Considerations

In this section, we discuss the technical considerations for design and implementing the lab-based Learning Objects.

3.1 Standards

In order for our lab-based Learning Objects to be easily integrated into the content-based e-Learning systems; we studied the standards defined for these systems. There are many organizations working on specifications related to e-Learning. The Advanced Distributed Learning (ADL) initiative [12] was established by the Department of Defense (DoD) in 1997. Fig. 1 shows the long-term vision of the ADL initiative. The Sharable Content Object Reference Model (SCORM) defines a Web-based learning “Content Aggregation Model” and “Run-time Environment” for Learning Objects [12].

There are other standard activities. The following four in particular play a vital role in the formation of next-generation learning technologies.

Alliance of Remote Instructional Authoring & Distribution Networks for Europe (ARIADNE) [13],

Aviation Industry CBT (Computer-Based Training) Committee (AICC) [14],

IEEE Learning Technology Standards Committee (LTSC) [15],

IMS Global Learning Consortium, Inc. [16].

Learning Object Metadata (LOM) standards also define many data elements that may be used to characterize learning-related content [17][18].

[pic]Fig. 1: Vision of the ADL initiative [12].

3.2 High-Level Requirements

To conform to the high-level requirements, defined in the SCORM references, following conditions should be satisfied [12]:

Accessibility: learning components should be accessible from remote locations.

Interoperability: components developed with one set of tools or platform should be able to work with components developed with a different set of tools or platform.

Durability: the design should be able to withstand technology changes without need to redesign, reconfiguration or recoding.

Reusability: it should be flexible to reuse the same components in multiple applications and contexts.

We are able to make the actual laboratory experiment available online; however, the accessibility of the lab-based Learning Objects depends on the number of identical physical units and also to the number of concurrent users. We have incorporated load balancing and queuing mechanisms in our infrastructure, which are responsible for fair usage of the lab equipment.

We assume a Web-based infrastructure as a basis for our system’s implementation.

Proposed Infrastructure

In order to test and implement our Learning Objects, we have used the framework of the OnlineLab project, which was developed at the Nanyang Technological University (NTU) [19].

4.1 OnlineLab Framework

The OnlineLab Framework can be considered as a container for our experimental Learning Objects. Every Learning Object integrated into the Framework can then share the resources provided by the Framework. Typical resources provided by the Framework are: user account management, experiment report generator, Communication Services with physical apparatus, Queue management, SMS reminder, Live video, discussion forum, automated Q&A services, etc. The use case diagram for our framework is depicted in Fig. 2. In this figure, the Lab-manager is responsible for performing system maintenance, such as adding or removing an experiment, creating or deleting user accounts and failure detection and recovery. As content provider for OnlineLab, the Course Instructor develops new Experiment Learning Objects, which make use of real apparatus. For Student, the OnlineLab is an e-Learning environment with a unique feature that also allows the student to conduct experiment using real apparatus.

Fig 2. Use case diagram for the OnlineLab.

4.2 Learning Object Model

In this section we introduce the Learning Object model for laboratory-based subjects. This model is an addition to the content-based model. Fig. 3 shows an overall architecture of the proposed model. The model is divided into three sections: OnlineLab Framework, Lab Unit and Server-side Unit.

As discussed in the previous section, the OnlineLab framework is a container for the Learning Objects. Many components of the framework are reusable and are shared by all the Learning Objects integrated into the framework. For example, all the Objects will share the load balancing, user account management, report generation, assessment tools, session management functions and database connectivity units. The session manager enables multiple students to join an ongoing lab session and keeps track of the users who have the control of the apparatus.

The server-side unit includes those components, which is installed in the OnlineLab server. The communications API provides all the necessary functions for initiating a connection to the actual lab unit and delivering data and control commands between the lab unit and the server. The communications API also includes facilities for streaming video from the camera located near the apparatus to the server. The GUI and Web API unit provides all the components for creating a web-based graphical user interface for the lab experiment, including tools for displaying the received data from an experiment.

[pic]

Fig 3. Proposed Learning Object Model for Online Lab experiments.

The communication between the Lab unit and the server side unit are all based on the eXtensible Markup Language (XML). XML is playing an increasingly important role in the exchange of a wide variety of data on the Web and elsewhere. Using XML makes the system interoperable with any XML-based lab equipment and any new lab unit can be integrated into the system in an easy “plug and play” fashion.

Finally, a lab unit is a combination of the hardware and software bundled with the actual apparatus. These include the embedded or PC based controller, a communication unit that enables the connection to the network and XML parser to receive and send control and status commands as well as the raw data. Every Lab unit has a unique identification number and will only communicate with the authorized server.

The lab unit receives commands for initializing the apparatus, start, and stop, shutdown and receiving the required parameters for a particular experiment. It also sends back to the server unit the raw data captured from the apparatus and status and fault reports.

Implemented Learning Objects

In this section, we introduce some of the lab-based Learning Objects we have developed at the school of Electrical and Electronics Engineering of the Nanyang Technological University [19]. All the experiments have been implemented within the framework we had already designed [6].

5.1 Optical Communication Lab

This Learning Object is to introduce students to one of the experiments in Optical Communication, namely SALITON. Soliton is a special kind of optical pulses that can propagate through an optical fiber undistorted for tens of thousands of kilometers. Hence, it has enormous potential in long haul communication systems. Fig. 4 shows the lab unit setup for the Soliton.

[pic]

Fig 4. The Lab unit for the Soliton.

5.2 Inverted Pendulum

The Inverted Pendulum is an apparatus which can be used for teaching subjects such as computer controlled systems or automatic control. Fig. 5 shows the lab unit for this Learning Object and Fig. 6 shows its Web-based user interface.

The Lab unit for the inverted pendulum has been used for two different experiments: Parameter Estimation and Controller Design. In the first Learning Object, the user is able to select an appropriate test signal and collect real data for estimating the apparatus parameters. In the second Learning Object, using the parameters identified as a basis for controller design, the students can verify their design by specifying the controller parameters and perform a swing up and balancing experiment on the actual inverted pendulum over the Internet.

[pic]

Fig 5. The Lab unit for the inverted pendulum

[pic]

Fig 6. Web-based user interface for the inverted pendulum Learning Object.

5.3 3D Shape Measurements

The idea of this Learning Object is to provide a Web-based online lab environment for 3D shape measurement and 3D Digital Watermarking. Using the system, a student is able to receive and process real-time 3D image data, which is sent from a remote camera via the Internet. The system will apply the phase-shifting technique to capture the 3D image data from a remote camera through the Internet and examine the quality of the image. Moreover, student is able to embed hidden watermarks into the captured 3D model. By changing the watermarking parameters, student could evaluate the performance of the algorithm. In this Learning Object, the Lab unit consists of a 3D digitizer and a camera plus some 3D object located in front of the digitizer. Here, we have also integrated content-based e-Learning into the system. This means that student is able to access documents which teach him/her the theory behind the 3D shape measurement and watermarking and at the same time conduct lab-based experiments.

[pic]Fig 7. 3D shape measurement Learning Object

Conclusion

In this paper, we presented a model for online laboratory-based experiments based on the Learning Object model. The reusable Learning Objects can easily be integrated into any e-Learning system that observes the standards. However, due to the physical limits for a lab unit, there should be a method to control the access to the equipment. We have introduced queuing and load balancing sub-systems to overcome this problem. We have also presented some examples of the Learning Objects we have implemented as part of our OnlineLab project. The study will be further carried out to improve the quality of the service, and to provide collaborative environment. We are also looking at the possibility of providing lab-based courses using grid computing techniques.

References:

[1] B. G. Wilson, Metaphors for instruction: Why we talk about learning environments, Educational Technology, 1995, 35(5):25-30.

[2] Lambertus Hesselink, Standford CyberLab: Internet Assisted Laboratories, Journal of Distance Education Technologies, 1(1), 22-39, Jan-Mar 2003.

[3] Sanchez, J.; Morilla, F.; Dormido, S.; Aranda, J.; Ruiperez, P., Virtual and remote control labs using Java: a qualitative approach, IEEE Control Systems Magazine, Volume: 22 Issue: 2, April 2002 Page(s): 8 -20

[4] Ko, C.C.; Chen, B.M.; Jianping Chen; Zhuang, Y.; Chen Tan, K, Development of a web-based laboratory for control experiments on a coupled tank apparatus, Education, IEEE Transactions on, Volume: 44 Issue: 1, Feb 2001 Page(s): 76 -86

[5] S.H. Yang, X. Chen, J.L. Alty. (2002) Design issues and implementation of internet-based process control systems, Control Engineering Practice 11 (2003) 709-720

[6] Ling KV, Lai YK and Chew KB, An Online Internet Laboratory for Control Experiments, Preprints of IFAC/IEEE Symposium on Advances in Control Education, 17-19 Dec 2000, Australia

[7] WU Sheng, LIM Choo-Min, LIM Khiang-Wee, An integrated internet based control laboratory, Preprints of IFAC/IEEE Symposium on Advances in Control Education, 17-19 Dec 2000, Australia.

[8] MIT iLab and webLab projects, Available at and .

[9] C. Szyperski, Component software: Beyond object-oriented programming, Addison-Wesley, 1998.

[10] J. Roschelle, J. Kaput, W. Stroup, and T.M. Kahn, Scalable integration of educational software: exploring the promise of component architectures, Journal of Interactive media in education, volume 6, 1998 (available at ).

[11] Wiley, Gibbons, Recker, A reformulation of the issue of Learning Object granularity and its implications for the design of Learning Objects, .

[12] The Advanced Distributed Learning (ADL) Initiative, Sharable Content Object Reference Model (SCORM), Version 1.2., Available at: .

[13]

[14]

[15] .

[16] .

[17] IEEE-Learning Technology-Learning Objects Metadata (IEEE 1484.12.1-2002), Available at: .

[18]IMS Learning Resource Meta-data Specification Version 1.2.1, Available at: .

[19] School of EEE, NTU, OnlineLab, Available at .

-----------------------

[pic]

................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download