Tools for collaborative eactivities

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Tools for collaborative e-activities

• G. Adorni, F. Bergenti, D. Bianchi, A. Poggi, M.
  Somacher

G. Adorni Università di Genova e-mail
adorni_at_dist.unige.it F.Bergenti, D. Bianchi, A.
Poggi, M.Somacher, Università di Parma, e-mail
bergenti,bianchi,poggi,somacher_at_ce.unipr.it
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Tools for collaborative e-activities This paper
discusses a system to facilitate activities
through the network (e-activities) offering tools
for collaborative work, video conferencing and
video on demand. The architecture of the system
is composed by two levels. The first level,
called collaborative level, allows remote users
to take part to a meeting where they can interact
with each other via a chatting line and by
sharing the use of different applications. A
second level, called multimedia level, allows a
multimedia interaction between the members of the
meeting. Each user must own a microphone, a CCD
camera and an internet connection with a
sufficient bandwidth to support the exchange of
audio and video data. We present some results
obtained during research activities (project
meetings, software design and debugging, document
writing) involving people connected from
different towns of Italy. The system was also
used in e-learning activities distributed through
a campus local network.
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• The Web in collaborative e-activities.
• The Web is assuming a central role in the way
  people share information.
• Web browsers are available everywhere and they
  provide an environment to integrate different
  services into a common, easily accessible,
  platform-independent user interface.
• The Web has already been adopted as one of the
  principal media capable of supporting the
  collaboration between people.
• Nevertheless, the basic communication facilities
  that the Web offers are not sufficient to support
  an interactive approach to collaboration.
• The communication needs for which the Web was
  designed was about consulting structured
  documents and was not about supporting an
  interactive discussion in a virtual group.
• The available Web technologies are not yet
  sufficient to implement the virtual-workgroup or
  the virtual-classroom metaphor.

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• The System Architecture
• Our system relies on a multi-level architecture.
• We define three levels that differ for (i)
  interactivity and (ii) requirements on the users
  multimedia equipment and on the available
  bandwidth.
• The higher is the level, the higher is the
  interactivity that the system offers and the
  higher are the requirements on the users
  equipment.
• The multi-level approach allows the system
  adapting to the capabilities of the user.
• We propose a solution that is completely based on
  off-the-shelf technology that also domestic users
  can access with small investments.

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Coarse-grained architecture of the system

• Users accessing the system through a domestic
  narrowband connection can still use the services
  of the collaborative level.
• Users with a wide band connection (eg. a campus
  local network) can also access the highest level
  and take part to an interactive multimedial
  virtual meeting.

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• Supporting collaborative activity
• In general terms, a collaborative activity is
  supported by group communication, i.e., by an
  exchange of information among a group of
  participants, the collaborators, in a session.
• Collaborators may play different roles in a
  session and the roles can change dynamically.
• Collaborators may also join and leave a running
  session.
• A collaborative platform is required to provide
  all the facilities needed to support the dynamic
  nature of the collaboration.
• A collaborative platform should guarantee the
  availability of suitable media for information
  exchange.

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• Synchronous vs. asynchronous collaboration
• A collaborative activity can be roughly
  classified into two categories, depending on the
  information exchange dynamism synchronous or
  asynchronous 
• Synchronous collaboration is characterized by a
  high level of interaction within the group all
  the collaborators share a single view of the
  discussion and the information is exchanged when
  it becomes available.
• Conversely, in an asynchronous collaboration, the
  information is transferred only on demand, thus
  lowering the degree of interaction in the group.
• The classic Web communication facility support
  only an asynchronous collaboration, mainly
  because HTTP protocol rely on a communication
  model in which the browser needs to request the
  information, as HTML pages, from the server.

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• The Basic Level I
• Our system supports synchronous collaboration in
  the middle and the high level. Nevertheless an
  asynchronous collaboration was added, as a basic
  level, to give access to HTML pages and to e-mail
  or news services.
• This basic level was introduced mainly to support
  e-learning activities.
• The system presents to the student a course
  module and its related tutorials through a Web
  browser.
• The theoretical part of the subject matter is
  presented through HTML pages.
• Linked to the main topics of the key chapters
  there is a series of tutorials (guided training
  exercises), presenting questions and problems
  that students are invited to solve offering
  software tools and simulating instruments for
  laboratory activities.

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• The Basic Level II
• At the end of each tutorial there is a
  self-assessment test composed of (i)
  multiple-choice, (ii) true/false, (iii)
  fill-the-blank and (iv) essay questions.
• While multiple-choice, true/false and
  fill-the-blank questions are corrected
  automatically, the essay questions need to be
  graded by the teacher therefore, if the student
  can access to an internet connection, the system
  automatically sends an e-mail to the teacher with
  all the information needed to evaluate the
  results of the test.
• At the same time, the student can take advantage
  of the e-mail connection to write her/his
  comments and to send questions to the teacher.
• A news group is used for general discussion.

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• Collaborative Level I
• Any collaboration support needs to provide
  consistency-guarantee mechanisms to correctly
  manage the shared information.
• In synchronous collaborative environment, where
  the collaborators share a single view of the
  shared information, consistency is typically
  managed by a floor-control policy.
• The explicit floor control policy enables only
  one group member at a time to modify the shared
  document. This modifying privilege is commonly
  described in terms of possessing the modification
  token.
• The distribution of the token to group members is
  performed by means of an intelligent policy
  supported by the voting mechanism.
• The modification-token holder can decide to
  submit a document change to members voting
  before committing it to a document-session
  revision.

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• Collaborative Level II
• The collaborative level is based on a
  collaborative implementation of Java AWT package
  that we called CollAWT.
• As the collaborative components do not extend the
  AWT component services, except for the
  collaboration support, the application is not
  aware of the presence of the discussion group
  thus providing collaboration transparency.
• This package is implemented by means of the
  event-broadcasting mechanism whenever a
  collaborative AWT component generates an event in
  reaction to an user interaction, this event is
  broadcasted to all group application instances in
  order to deal with it as if it was generated by
  the local user interface.
• Only the token-holders components are active,
  meaning that they can interact with the user,
  while all others components are passive.

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Collaborative Level III

• Events broadcasting is implemented by the events
  channel service which acts as an events broker.
• After an event is fired by the user interface,
  the generated object of class AWTEvent is
  serialized and pushed into the events channel.
• The events channel then broadcast the received
  data to all group applications.
• Once received by an instance of the collaborative
  application, the AWT event is treated as if it
  was generated locally meaning that it is passed
  to the application.

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• Collaborative Level IV
• A user can join or leave a group at any time.
• At login the new member receives an instance of
  the shared application while all group members
  are informed of this event.
• The system supports unanticipated sharing of the
  application and latecomers can decide to enter
  into the discussion in a synchronous or
  deferred-synchronous way.
• In the synchronous way, the latecomer is
  immediately accommodated in the group with a view
  of the shared document.
• Conversely, in the asynchronous login procedure,
  the latecomer is shown all the changes occurred
  to the document since its last leaving.
• The shared-application instances are synchronised
  starting from a common state and evolving by
  means of user-interface generated events.
• The deferred synchronous policy is performed by
  the latecomers application asking the
  transaction-logging service to play back all
  events occurred since its last group leaving.

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• Multimedia Level
• The multimedia level integrates audiovisual
  components in our system to improve its
  effectiveness from the point of view of the
  communication among the meeting participants or
  in the learning process.
• Two different tools
• A videoconferencing tool.
• A tool for consulting audiovisual documents
  stored in digital format.
• Are realized using Java Media Framework and
  implements the floor control mechanism.

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• Virtual Teams I
• We have used the described e-activities
  collaboration and communication facilities to
  manage a virtual team. We are experimenting this
  tool in research activities. Examples are
  project meetings, software design and debugging,
  document writing.
• To support these activities we have tailored a
  collaborative platform, named JWebTop, that
  supports sharing of documents and of Java
  applications for collaborative work.
• The platform gives to the participant to the
  virtual meeting the use of a shared textual and
  graphical editor, and a web browser.
• The editor allows participants to work to a
  shared document while the meeting is in progress,
  the web browser allows to display HTML text, or
  to present slides during a talk.
• We are using this platform for scientific
  meetings with people distributed at home/office
  of many towns in Italy.

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• Virtual Teams II
• The collaborative level provides as a
  communication tool a chatting line. But the
  exchange of written messages is very slow and
  annoying. To facilitate people communication an
  audio-conferencing or video-conferencing tool is
  also provided.
• While a video conference requires a wide-band
  communication channel, the audioconference
  requires a narrow-band, but it is usually
  sufficient to guarantee an adequate level of
  communication amongst the people involved in a
  meeting.
• In the user interface of the client application a
  person can require or release the floor. The
  floor request are managed by a FIFO policy. Only
  the user holding the floor can use the editor or
  the web browser.
• On the contrary in the audio conference each user
  broadcast an audio stream to all the
  participants. Voices from different users can be
  mixed. It depends on the politeness of
  participants to regulate the dialog turns.

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• E-Learning Basic Teaching/Learning Scenarios I
• the transmission scenario related to the empty
  vessel metaphor (old-fashioned prevailing
  classroom teaching and lecturing). This scenario
  is characterized by a closed domain, well-defined
  learning goal, fixed learning route, instruction
  and practice, diagnosis of errors and
  remediation. The expected outcomes are domain
  knowledge and skills
• the studio scenario related to the constructive
  agent metaphor (current study-house). It is
  characterized by open or closed domain,
  well-defined learning goal, flexible learning
  route, project-based learning, interaction with
  different agents (human or otherwise) The
  expected outcomes are domain knowledge as well as
  social and practical skills
• the negotiation scenario related to the
  situated/distributed cognition metaphor
  (post-modern). Characterized by open domain,
  ill-defined learning goal, open learning route,
  argumentation, negotiation and reflection. The
  expected outcome regards conceptual changes.

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• E-Learning Basic Teaching/Learning Scenarios II
• A prevailing transmission scenario is mainly
  reflected in classroom teaching, lecturing, drill
  and practice while there is little room for
  discussion/reflection and for complex problem
  solving. It is mainly used to teach and learn
  domain facts and rules transmission. Most of the
  classical intelligent tutoring systems, mainly
  interested in domain and student modeling, fit in
  this class.
• The studio scenario has more emphasis on complex
  problem solving, on student initiative and
  responsibility on problem analysis and solving
  method selection, more emphasis on open tasks
  (writing an essay, conducting a debate, giving a
  talk). Main aim is to teach and learn procedures
  and problem solving strategies. The modeling
  issue moves away from representing the cognitive
  states of the individual students to support
  interactions between users in a situation in
  which students have to confront with multiple
  tasks and multiple source of information. Our
  work may be considered as an example of this
  scenario.
• The negotiation scenario, is based on student
  directed learning, student defined problems and
  solutions, student sharing of knowledge and
  evolving ideas. It is devoted to teach and learn
  meta-cognitive skills, to create new knowledge
  and to reflect on ones understanding. May be
  promoted by the use of e-activities tools.

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• E-learning an example of courseware
• A campus network was used to give access to a
  courseware case study. The system that we
  realized integrates the Web with the classic
  e-learning process to offer students and teachers
  services with different degrees of interactivity
  ranging from off-line document consultation, to
  web based document browsing and e-mail
  communication, to virtual classrooms.
• The collaborative level offers an
  application-sharing service to allow integrating
  the lesson with experiences on, e.g., simulated
  instruments and tools for laboratory activities.
• The multimedia level allows the integration of
  course materials with audiovisual documents to be
  used individually or in the virtual classroom.

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The campus network We have two different
networks. The first is the TCP/IP intranet of the
Campus. This network is normally used for all the
activities of the basic and collaborative levels,
i.e., access to the Web server, to the mail and
news services, to the chatting line and tools for
collaborative work. The Campus network can
support those services that do not require a
fixed bandwidth allocation. On the contrary,
multimedia service needs a guaranteed wide band
connection to transmit video or audio data. So, a
second network based on ATM technology connects
the video server with the classrooms and labs.
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The campus network The ATM network connects the
video server with classrooms and laboratories. It
is supported by a PON (Passive Optical Network)
with a bandwidth of 622 Mbit/sec download and 155
Mbit/sec upload. The fiber optical network is
connected with the user equipment using an ADSL
switch which is also connected to Campus Intranet
(Fast Ethernet).
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• An Example of Courseware Hyperprolog I
• The campus network was used to give access to a
  courseware case study in which the different
  levels can be implemented and tested. The subject
  matter of the module is Mathematical Logic,
  Logic Programming and Prolog.
• The theoretical part of the subject matter is
  presented through hypermedia (which are made of
  hypertext and other kind of materials as
  audiovisual documents, animations).
• The course contains also a number of topics
  related to artificial intelligence natural
  language processing, knowledge representation,
  fuzzy logic, learning, temporal logic.
• Linked to the main topics of the key chapters
  there is a series of tutorials (guided training
  exercises) with questions and problems that the
  students are invited to solve.

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• An Example of Courseware Hyperprolog II
• Students can actually try out their answers and
  solutions by using, within the browser, an
  available Prolog interpreter on the server
  together with a number of files related to the
  examples presented in the tutorials. These sample
  files can be directly loaded and tried out in
  this environment which we called PrologLab.
• Also for the AI topics there are a number of
  working examples that the students can try in the
  PrologLab environment.
• Students can easily switch from the hypertext to
  the PrologLab or use both concurrently.
• At the end of each tutorial there is a
  self-assessment test which the students can take.

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• Collaborative PrologLab
• In order to allow a direct distance interaction
  between teachers and students, a collaborative
  environment has been developed.
• The aim is to realize a virtual classroom in
  which the teacher can demonstrate the use of the
  PrologLab, develop programs interacting with the
  students, test the program with the Prolog
  Interpreter.
• All participants in the classroom have to see the
  same information on their screens. Moreover each
  participant can, in an ordered fashion, gain
  control of the collaborative resources end use
  them. For example can edit a file, consult a
  program in the Prolog database, execute a Prolog
  query and so on.
• The collaborative PrologLab may also be used by
  group of students working to a common project
  over the network.

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The Collaborative PrologLab Interface Participant
s can edit and test programs, use a chat line,
enter or exit session, request or release the
floor.
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• Collaborative PrologLab Floor Management
• Different floor management policies can be
  adopted.
• Because our aim, with the collaborative tools, is
  to reproduce a lesson, we can assume that the
  teacher may decide, on the basis of a request
  list, which student has the floor and so have an
  exclusive control of the application resources.
• At any time, the teacher can also gain the
  control of the floor previously given to a
  student.
• On the other hand, if the collaborative tools are
  used by a group of students working to a common
  project a more democratic policy of floor
  management should be adopted.
• A voter list is maintained to allow collective
  decisions and the members of the group can vote
  to accept or reject a proposed change to the
  current program.

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• System evaluation I
• Analysis of the students patterns of activity by
  means of system logs. This analysis will give
  information about students use of the system,
  which pages of the text they looked at most,
  which facilities they used the most (tutorials,
  self test, PrologLab, e-mail, conference area) or
  which ones they overlooked.
• Effectiveness of the system in terms of the
  students learning outcomes. This evaluation is
  based on the results of the final test.
• Students attitudes toward the resource. A
  questionnaire was administered to the students to
  assess how much they liked this resource in
  comparison with more traditional courses. They
  were asked which part of the system they used
  most and which ones least, which ones they felt
  as difficult to use and why.
• The result of the questionnaires were integrated
  with the information gathered during focused
  group discussions on the topic.

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• System evaluation II
• Analysis of chat recording in the collaborative
  PrologLab can be used to study the interaction
  between students in working groups.
• Questionnaires can be used to test the
  satisfaction of the participants to a virtual
  meeting.
• We can obtain information about the easiness of
  use of the tools, the effectiveness of the
  communication with the chat line or the audio
  conference or the video conference, the
  usability at work/home with different
  communication bandwidth available.