A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> Both chemistry teachers and nonmajor students appear to agree that freshman chemistry may well be the most problematic traditional science discipline taught in the first year of college—as far as students' misunderstandings, learning difficulties, and misconceptions are concerned. The above is probably due to the many abstract, nonintuitive concepts, which are not directly interrelated. Consequently, in such cases, the powerful, general teaching strategy of “concept mapping” must be replaced by alternative, specific strategies. Selected illustrative examples of students' learning difficulties and misconceptions in freshman general and organic chemistry are presented in the students' terms, followed by the corresponding successfully applied, specific, concept-oriented, eclectic intervention strategies the author uses in order to overcome the difficulties. Based on longitudinal in-class observations, interpretive study, and analysis it is suggested that those students' misconceptions in freshman chemistry which are not interrelated logically and/or derived from one another are not prone to the general “concept mapping” approach and should be dealt with by using the appropriate, specific teaching strategy. <s> BIB001 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> This research investigated students' understanding of electrochemistry following a 7–9-week course of instruction. A list of conceptual and propositional knowledge statements was formulated, and this provided the framework for semistructured interviews that were conducted with 32 students in their final year of high school chemistry, following instruction in electrochemistry. Three misconceptions identified in this study and five which have been reported earlier are incorporated into an alternative framework about electric current. The framework is grounded on the notion that a current always involves drifting electrons, even in solution. Another area where students' misconceptions were prevalent was in relation to the sign of the anode and cathode. Students who thought the anode was negatively charged believed cations would move toward it, and those who thought it was positively charged were unable to explain why electrons move away from it. Electrolytic cells also proved troublesome for students. Many students did not associate the positions of the anode and cathode with the polarity of the applied electromotive force (e.m.f.). Other students attempted to reverse features of electrochemical cells and apply the reversals to electrolytic cells. The implications of the research relate to students' interpretation of the language that is used to describe scientific phenomena and the tendency for students to overgeneralize, due to comments made by teachers or statements in textbooks. <s> BIB002 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> The Center for Telecommunications at Stanford University, in partnership with the Stanford Center for Professional Development, has designed and deployed an experimental system for delivery of Stanford courses in multimedia format to distance learners using the Internet as well as two experimental, asychronous transfer mode (ATM)-based, high-speed network testbeds. This configuration is designed to prototype the emerging broadband communications infrastructure in the United States and elsewhere. The courses are stored on servers and made available to distance learners on-demand. The user interface is implemented on the World Wide Web. Issues of systems integration, educational effectiveness, and economics are under study as part of the project, called ADEPT (Asynchronous Distance Education ProjecT). In this paper, ADEPT is described along with its experience to date. <s> BIB003 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> Presents important issues in the design and implementation of a multimedia digital classroom (MDC) system, together with its applications. The MDC system is implemented in the Java language. It aims at providing important tools to support a distributed interactive education environment. The system consists of a classroom manager and some powerful teaching application tools. The classroom manager is a sharing system with a database. The teaching application tools include a multimedia Internet browser, a shared white-board, multi-channel audio conferencing, a World Wide Web-based note-taking system and an instruction evaluation system. The MDC system and these application tools have been implemented and tested in a heterogeneous environment where workstations and PCs are connected through networks. <s> BIB004 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> A multimedia micro-university supports the education programs and management operations of a small academic institution. The authors describe its important components-a virtual library, an intelligent distance learning system, and visualization and planning tools for management operations-and discuss an assessment plan designed to evaluate the micro-university's effectiveness. <s> BIB005 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> The Boston University College of Engineering Distance Learning Initiative (DLI) integrates computers, digital video, and the Internet to deliver graduate degree courses in engineering to students in companies distant from the Boston University campus. A key objective of the DLI is to support learning wherever it is most convenient, whether by groups in a classroom, at the workplace desk, or at home. The article describes the motivation, technology, and experiences in integrating a satellite-based digital video distance learning system coupled with Web technology. <s> BIB006 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> The option of obtaining education over networks is quickly becoming a reality for all those who have access to the Internet and the World Wide Web (WWW). However, at present, network-based education (NBE) over the WWW and the Internet in general faces a number of pitfalls. The problems range from inadequate end-user quality of service (QoS), to inadequate materials, to shortcomings in learning paradigms, and to missing or inappropriate student assessment and feedback mechanisms. In this paper, we discuss some major issues that, although mostly solved for NBE, still face Web-based education (WBE). These include the required workflow-oriented technological and quality of service support. In discussing the issues, we use examples from a wide-area NBE/WBE system called NovaNET and a WBE system called Web Lecture System (WLS). We recommend that WBE system developers construct operational user (workflow) profiles before building their content and interfaces. Our experience is that, especially for synchronous WBE systems, user-level round-trip keystroke delays should not exceed about 250 ms and the overall availability of the system (including network-related service failures) should be at least 0.95. We also suggest that a successful WBE system will have a sound auto-adaptive knowledge assessment component, a virtual laboratory capability, and a set of strong collaborative functions. Until WBE systems match teacher/instructor and student workflows both technologically (as an appliance) and pedagogically, WBE, except in its most primitive form, will not be an effective educational tool. <s> BIB007 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> Currently, the WWW has created an open environment for convenient delivery of HTML pages and low bandwidth video clips. Since HTML pages can present static text and image in much higher resolution to that presented by a low bit rate video clip, we believe that the optimal mode for a WWW based distance lecture is to use: (1) streaming video clips for the audio/video lecturing, and (2) dynamically loaded HTML pages to present the lecture note navigation process. To this end, we have designed a "Live/On-Demand Synchronized AV/HTML Distance Lecture System" to synchronize the presentation of the streaming video lecture, the HTML based lecture notes, and the HTML Navigation Events. We propose a "Web-based Synchronized Multimedia Lecture (WSML) "framework to automate the recording of the media presentation events based on the SMIL specification. The WSML framework consists of three major modules: (1) WSML Recorder for recording the temporal information of the AV lecture; (2) WSML Event Server for receiving, multicasting and depositing WSML events; (3) WSML Browser for presentation of the synchronized AV lecture and HTML based lecture notes navigation. To evaluate the performance of the propose framework, in this stage, we have applied the RealSystem to implement a prototype Synchronized AV/HTML Distance Lecture System using Java/Javascript. The prototype system demonstrates the feasibility of the proposed framework. <s> BIB008 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> Evolution and cost of measurement equipment, continuous training, and distance learning make difficult to provide a complete set of updated workbenches to every student. For a preliminary familiarization and experimentation with instrumentation and measurement procedures the use of virtual equipment is often considered more than sufficient from the didactic point of view. Creation and distribution of workbenches in networked computer laboratories becomes therefore attractive and convenient. This paper describes specification and design of a geographically distributed system based on commercially standard components. <s> BIB009 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> There are numerous initiatives for maximising benefits to teaching and learning in higher education using information technologies, especially those utilising the World Wide Web to provide a user-friendly, multimedia interface. The expanding population of students and increased demand for flexible education underline the need to take advantage of these technologies without incurring large overheads in terms of development and infrastructure. The aim of this paper is to demonstrate the development of Web-based, interactive simulations, to evaluate the benefits based on user trials and to illustrate the potential for a widely accessible educational environment. <s> BIB010 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> This article presents the results of a research project that requires students and faculty to evolve a virtual community in a university class. The concepts, requirements, and importance of a virtual community are discussed, along with the skill requirements necessary for students to participate effectively in a virtual community. The Web sites and class assignments that form the basis of a virtual community are described. Finally, the importance of enriching the learning experience and humanizing the learning process through the use of a virtual community is also discussed. <s> BIB011 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> This paper reports the results of a five-year effort to develop an effective system for teaching distant students via the Internet, where the students are able to participate synchronously in class as contrasted to the more common asynchronous, Web-based "distance learning" approach. The authors have developed a system consisting of effective teaching practices and a practical family of software to support this approach within the context of computer and network resources that are available to average students at home or in an office. The system and the process that developed them are described in detail. They conclude with the outcome of a graduate course taught to three sections totalling 68 students (including a local control group) using this approach. <s> BIB012 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> A prototype of an ATM-based real-time multimedia communication system is developed over Fore Runner ASX-200 ATM switches and the Sun Spare/Solaris platform with ATM adapters and Video Plus. The system includes video/audio collection, compression, playback and transmission over ATM VBR SVC (variable bit-rate switched virtual connection). Client-server mode is adopted in the system to manage the two styles of connection: multicasting and point-to-point connection between two users. A method is also proposed to support the request to join a multicasting group initiated by a client over UNI 3.0/3.1 signaling. To facilitate VBR video over ATM, a leaky-bucket rate control method is developed and employed for reliable and efficient video communication. A multimedia distance learning system built over our framework is also introduced in the paper. <s> BIB013 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> The paper reports on an investigation into one of the most urgent problems facing distance language education: the problem of lack of exposure to speaking practice in the target language. The Open Learning Chinese Program taught at Griffith University is used as a case study. Following a discussion on issues relating to distance education for languages such as the indispensability of technology to learning languages in a distance mode, and the importance of communicative competence, the paper moves on to an examination of the capabilities of Internet based real time technology. Two major indications can be generated from this research: real time technology can help solve the problem of insufficient exposure to speaking practice, and a historical convergence of distance and traditional campus based education toward a networked education can be expected. <s> BIB014 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> The paper shows a distance learning system with huge benefits, that incorporates two methodologies for distance learning: with and without the presence of the teacher, professor or speaker. This system allows giving a class in real time, creating and studying multimedia courses. For the interactive courses, the system uses several protocols over IP, and several compression algorithms. Also the parameter QoT (Quality of Teaching) is defined. The system has been designed in a modular structure so that new modules can be easily added. <s> BIB015 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> MOCA is a suite of Internet multimedia tools to facilitate groupwork in a distance learning environment, built using standard Java utilities. MOCA's original aim was to allow several users to work simultaneously on multimedia documents using a multimedia whiteboard. Now MOCA supports both asynchronous and synchronous collaboration models. Tools for asynchronous multimedia presentation, annotation, surveys, and HW have also been developed using the same basic framework. To enable synchronous collaboration sessions between students, TAs and instructors, we have developed a scheduler tool. The system is being piloted in an advanced VLSI chip design course which allows multimedia collaboration between design teams distributed at academic sites at UMASS/Amherst, ENST/Paris, Pusan South Korea and industrial sites at IBM, Intel, AMD and Motorola. <s> BIB016 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> The "schooling industry" is faced with an inescapable demand to redefine its endeavors in terms of producing learning, rather than providing instructions. We propose a hybrid learning model to attract distance as well as traditional students. One of the major components of this model is the Web-based learning and interaction. We review the available avenues of distance learning and offer a model that we prepared as an example of Web-based distance learning and training. This model combines videoconferencing, interactive classroom, Web-based lectures and traditional instructions in an optimized way to achieve the goal of high quality technical education. The availability of lecture notes and other course material on the Web makes it a 24/spl times/7 hours classroom. Conducting classes via videoconferencing ensures student participation from all locations and optional interactive conventional teaching strengthens the student-teacher relationship and reinforces the concepts in the minds of students. Therefore, we believe this model offers one of the best opportunities in Web-based distance learning. This paper presents the hybrid learning model and discusses the opportunities and challenges of the Web technologies in the education of computer science and engineering. Through this hybrid model we have already successfully offered several courses in the computer science program at SUNY Fredonia with students registering from across the New York State. <s> BIB017 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> Traditional modes of communications are inadequate for distance learning in the information age. With advances in computer technology, the Internet offers great opportunities for educational exchange of ideas across vast distances. This paper proposes an end-to-end solution for streaming 'live' and recorded multimedia lectures over the Internet. The technical issues involved are first discussed and the importance of application-layer QoS control in ensuring an acceptable quality of multimedia lecture play-out emphasised. A hybrid architecture that uses an exchange server to handle communications and represents an optimal balance between several conflicting requirements is then proposed. In this architecture video/audio data are transferred directly between the streaming servers and clients. Objective and subjective tests have validated the effectiveness of the design. <s> BIB018 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> Distance Learning system is one of the most important applications of multimedia and communication technologies. In the past few years, Tamkang University has a special interesting group of research faculties from computer engineering, education, and literature departments. We follow the operation procedures of a virtual university, and developed Distance Learning system is one of the most important applications of multimedia and communication technologies. In a set of tools to be used by students, course designers, and instructors. <s> BIB019 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> Establishing a Web-based distributed multimedia presentation system environment is technical challenge. In this paper, we describe how to present different multimedia objects indispensably on a Web presentation system with a floor control mechanism, to be used in a distance learning environment. The distributed approach is based on an extended timed Petri net model. Using the characterization of extended timed Petri nets, we express the temporal behavior of multimedia objects. Then we introduce the concepts of user interaction. The main goal of our system is to provide a feasible method to represent a schedule and navigate different multimedia objects with user interaction. In addition, users can dynamically modify and verify different kinds of conditions during the presentation. To verify the structural mechanism, we implement an algorithm using the Petri net diagram, analyzing the model by a time schedule of multimedia objects, and we produce a synchronous set of multimedia objects with respect to the time duration. In particular, we consider the interactive facilities needed to support the distance learning requirements. We propose a floor control mechanism which provides four types of control (free access, equal control, group discussion and direct contact). These control mechanisms are sufficient for use in a distance learning environment. <s> BIB020 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> The innovation brought by the introduction of new technologies in our modern society has also started to appear in education. The biggest efforts come from the institutions involved in distance education, partly due to the characteristics of the educational system they represent. In order to improve the technology development there are a large number of projects being developed inside the European Union. This paper discusses the current situation of distance learning and the technological resources available including e-mail, video conferencing, Internet and the World Wide Web and virtual teaching-learning environment. Some of the European Projects including new technologies in distance learning are also discussed. <s> BIB021 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> E-learning is one of the killer applications in the new information society. Many educational systems have been developed, targeted to specific learning environments. One specific area of concern is practical training. This paper presents the latest update on the WWW-based teaching laboratory SimulNet. Particularly, we describe the functionality of the SimulNet whiteboard and authoring tools. Among others, the whiteboard features allow any kind of data sharing on the Web, on-line synchronous communication among learners and instructors and the possibility of following virtual presentations with an embedded Web-based slide projector. The SimulNet authoring environment includes a multimedia editor tool and both static and dynamic content structure generator. Also, current efforts in the learning technology standardization process were taken into account. We set the basis to become SimulNet compliant with the leading standard recommendations. <s> BIB022 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> Lecture-on-demand (LOD) multimedia presentation technologies in networks are most often used in communication services. Examples of those applications include video-on demand, interactive TV and communication tools in a distance learning system, etc. In this paper, we describe how to present different multimedia objects on a Web-based presentation system. The distributed approach is based on an extended timed Petri net model. Using characterization of extended media streaming technologies, we developed a Web-based multimedia presentation system. For a real-world example, suppose a well-known teacher is giving a lecture/presentation to his students. Because of time constraints and other commitments, many students cannot attend the presentation. The main goal of our system is to provide a feasible method to record and represent a lecture/presentation. Using a browser with windows media services allows those students to view live video of the teacher giving his speech, along with synchronized images of his presentation slides and all the annotations/comments. In our experience, this approach is sufficient for distance learning environments. <s> BIB023 </s> A Survey of Distance Education Challenges and Technologies <s> Communication Technologies <s> Mobile agent techniques involve distributed control if communication is required among different types of agents, especially when mobile agents can migrate from station to station. This techniques can be implemented in a distributed distance learning environment, which allows students or instructors to login from anywhere to a central server in an education center while still retaining the look-and-feel of personal setups. In this research paper, we propose a distributed agent framework along with its communication messages to facilitate mobile personal agents, which serve three different groups of distance education users: instructors, students, and system administrators. We propose an agent communication framework as well as agent evolution states of mobile agents. The communication architecture and message transmission protocols are illustrated. The system is implemented on the Windows platform to support nomadic accessibility of remote distance learning users. Personal data also migrate with the mobile agents, allowing users to maintain accessibility to some extent even when the Internet connection is temperately disconnected. Using user-friendly personal agents, a distance education platform can include different tools to meet different needs for users. <s> BIB024
Communication and network technologies can be divided into several levels. According to the ISO standard, network architectures can be divided into seven layers. However, other new technologies, such as ATM, use a different architecture. From the perspective of communication tools that are used in distance education, we focus on the network application level, which includes integrated systems rely on other lower level technology, such as those for realtime media streaming. In addition, the communication technologies we discuss here are not from the perspective of human interaction, either are they related to human-computer interactions. Related to broadband communication technologies, there are a few articles. In  , distance-learning applications were tested over an IPv6/ATM-based broadband facility. The conclusion states that, users must understand the consequences of QoS differentiation, and the cost they paid. Another ATM-based conference system BIB013 supports multicasting and point-to-point communication. The chapter also discusses an application for distance learning based on this technology. On the other hand, an agent-based architecture (i.e., mStar) to support the development of real-time communication is discussed  . In the article, a bandwidth manager agent determines how bandwidth should be utilized. The strategy adapted considers the number of users, as well as the number of media used. In  , an interactive learning system supports twoway video, on-the-fly interaction, and application sharing is implemented on a high speed network. A prototype configuration, based on ATM network, for courses on-demand was developed at Stanford University BIB003 . Experiences including system integration, educational effectiveness, and economics are also discussed. BIB014 also proposed a real-time communication tool to teach speaking skills. A real-time interactive Web-based teaching system for engineering students was developed in Hong Kong  . Another real-time interactive virtual classroom tool is presented in  . New coding algorithm is used to enhance the quality of handwritten text video. A set of tools were also developed to record live classroom sessions. The use of operational user profile and the control of end-user QoS are suggested in BIB007 . The conclusion suggests a range of user-level delays, which is acceptable by most users. The chapter also recommends a number of facilities for the developers of distance education systems, to make the systems effective. A low-bandwidth streaming technology focuses on the application layer QoS is discussed in BIB018 . A hybrid architecture using an exchange server is able to avoid the conflicting requirements, and to allow efficient point-to-point transfer. From the above discussions, we realize that real-time media streaming technology, with the control of quality of services, will be important for interactions in distance learning. In addition to network-based tools, middleware systems to support distance education, or to enable the integration of tools are widely found in the literature. A set of distance-learning tools BIB019 , including a shared whiteboard and a chat room tool, are integrated to a distance-learning environment, which provides a complete platform for distance education. Another distance lecture supporting system BIB008 for streaming video clips and dynamically loaded HTML course content is developed, based on a synchronization framework known as WSML (Web-based synchronized multimedia lecture). Huang (2000) also uses Windows media streaming technology to integrate a distance system, which supports both real-time communication and on-demand-based media production. A distance-learning system (Duran-de-Jesus, Villacorta-Calvo, & Izquierdo-Fuente, 2000) for real-time teaching and interactive course is proposed. Parameters for the measurement of QoT (quality of teaching) are also defined in BIB015 . A distance-learning system BIB004 based on Java is implemented to facilitate communication, management, and the evaluation of distance learning. This system is designed to work on a heterogeneous environment to support PCs and workstations. Another Java-based network educational system  ) is also developed to support tele-teaching applications. For communication, a mechanism to control who to speak in a distributed virtual environment is proposed BIB020 ). The control mechanism can be used for multimodal, multichannel, and multi-user communications. A client-server distributed environment BIB009 to support virtual lab, using commercially standard components, is discussed. The system is tested by a class of students learning electrical measurements in different connections and operating conditions. Another Web-based remote laboratory  for the experiments on a coupled tank apparatus was developed at the National University of Singapore. Video conferencing technique is used to provide audio and video feedback. A Web-based interactive simulation tool for electronics was developed in Scotland BIB010 . In a larger scale, a number of distance projects BIB021 to improve the technology of collaboration and communication were discussed. Experiences of building a virtual community for enriching e-learning experience and humanizing learning process are discussed in BIB011 . In addition, Multimedia MicroUniversity BIB005 ) is a project arms to support the management and operation of distance education of a small academic institution. A virtual library tools and an intelligent system are implemented to support online tutoring. Skill requirements to build efficient virtual community are presented. The experience of using satellite-based digital video, Web technology, and Internet-based interactions is also discussed in BIB006 . Lecture recording and playback systems using video and PowerPoint presentation are presented BIB023  . A suite of Internet multimedia tools support both synchronized and asynchronized collaboration is presented in BIB016 . The SimulNet BIB022 distance-learning platform includes a few tools, such as authoring and communication tools. A set of synchronous distance education tools is also proposed in BIB012 . A system supports both synchronous and asynchronous mode of collaboration is proposed in BIB016 . The system is used in a VLSI chip design course. A system allows video conferencing, interactive classroom, Web-based instruction, and traditional lecture is proposed in BIB017 . Mobile agent technologies were used in a distributed distance-learning system BIB024 , which allow students to have persistent personal data while they are accessing a centralized distance-learning server from different locations. In addition to the communication tools used in a virtual community, Virtual Reality (VR) is a good medium, in distance learning, for making abstract concepts concrete, for example to touch or to manipulate virtual geodesic domes and to observe theirs symmetries  . The difficulty of understanding scientific concepts is well-researched BIB002 . BIB001 has affirmed: "Students' misunderstandings and misconceptions in school sciences at all levels constitute a major problem of concern to science educators, scientist-researchers, teachers, and, of course, students" (p. 1054) . Virtual reality can also help constructivist learning  . Virtual reality modelling language (VRML) can help to create virtual objects in the cyberspace.