Analysis and Outcomes of the Grid-Enabled
Engineering Body Scanner
Kevin T. W. Tan1, Daniela Tsaneva2, Michael W. Daley2, Nick J. Avis2, Philip J. Withers1
1
Manchester Materials Science, University of Manchester, Grosvenor Street, Manchester M1 7HS, UK
1
Corresponding Fax: +44(0)-161-306-3586
2
School of Computer Science, Cardiff University, Queen’s Buildings, Newport Road,
P.O. Box 916, Cardiff CF24 3XF, UK
Abstract
This paper presents initial analysis and outcomes from the Integrated & Steering of Multi-Site Experiments
for the Engineering Body Scanner (ISME) Virtual Research Environment (VRE) project to enable
geographically remote teams of material scientists to work together. Comparisons between different
AccessGrid (AG) tools have been made, allowing us to identify their advantages and disadvantages
regarding quality (visual and audio) over broadband networks, utility, ease of use, reliability, cost and
support. These comparisons are particularly important when considering our intended use of AG in nontraditional, non-office based settings, including using slow domestic broadband networks to run AG
sessions from home to support experiments at unsociable hours. Our detailed analysis has informed the
development of a suite of services on the web portal. Besides user interactions, a suite of services based on
JSR-168 had been developed for evaluation. Each service has been evaluated by materials scientist users,
thereby allowing qualitative user requirement gathering. This feedback has resulted in a prioritised
implementation list for these services within the prototype web portal allowing the project to develop useful
features for material scientists and the wider VRE community.
1. Background
The safe lifetime of a manufactured component can
not normally be predicted simply by knowing its
geometry and the stresses applied to it externally.
Also important are any defects or flaws as well as
residual stresses that self-equilibrate with the
component. These residual stresses arise as a
consequence of manufacture and previous service and
add to any externally applied stresses. A number of
complementary material characterisation techniques
have been developed capable of providing 3D maps
of structure and stress inside engineering
components. This inside information allows the
integrity and lifetime of the structure to be predicted.
The fact that the experimental methods are noninvasive means that the evolution of structure in
response to service conditions (static loads, fatigue,
stress corrosion environments, etc) can be followed in
real time through life.
Experiments to measure residual stresses often take
place at International User Facilities (Figure 1),
where the experimenters must work at speed,
continuously during 24 hours/day experiments.
Beam time is very precious and it may be months
before another time slot is available to the team.
Limitations associated with travel mean that often
post-doctoral researchers and/or PhD students travel
to the site and must work in shifts alongside
instrument scientists. Furthermore, key decision
points are often encountered late at night and without
the benefit of a preliminary analysis of the collected
data. Due to inexperience/tiredness simple mistakes
are sometimes made which are only revealed
subsequently off-site upon detailed analysis and too
late to rectify the situation by modifying the set-up
on-site.
Telephone calls and email have been the primary
methods to support remote discussions between the
experimental site and the scientist’s university or
home to explain the problems encountered and to
utilise the expertise knowledge. The asynchronous
nature of email can dislocate the exchange of ideas
and renders brainstorming impossible. Experimenters
also need to discuss the newly obtained experimental
results, often by sharing customised analysis
applications (2D and 3D visualisation) between
experiment site and university / home. It is therefore,
preferable to allow the various participants to log-in
to a shared server which hosts the required
applications to support common data analysis,
visualization and discussions. Experimental thinking
time is precious and so the interaction infrastructures
must be natural and unobtrusive to gain wide-spread
acceptance. Furthermore the infrastructure must be
capable of supporting users in non-traditional nonoffice based situations – for instance the scientist at
home connecting using domestic broadband services.
We have previously presented the need for advanced
collaborative tools to support residual stress
measurement experiments [1]. This paper describes
the work in progress of the current JISC-VRE project,
Integrated & Steering of Multi-site Experiments for
the Engineering Body Scanner (ISME) focussing on
the:
1). evaluation
of
AG
tools
to
assist
communication between remotely located
experimenters and teams at university / home;
Figure 1: A beamline at an international Facility (ESRF)
2). analysis of various web services required in a
web portal to aid and assist experiment/data
management.
It is important to remember this project is primarily
about examining the extent to which VREs can
assist distributed teams carry out experiments,
rather than to develop novel or sophisticated VRE
tools. Our focus is very much on the seamless and
transparent integration and takes up of low
cost/accessible infrastructure technology and the
identification of the most important tools and their
role/impact in supporting 24 hour experiments at
international facilities.
2. Existing ISME System
The ISME project is funded as part of the JISC-VRE
Programme with the aim of integrating and refining
existing tools into a VRE to make them deployable
by teams of instrument scientists, material scientists
and engineers in a transparent and robust manner. It is
helping to extend the culture and functionality of
collaborative multi-site experiments. Whilst this
project is partly concerned with the technicalities of
VRE-based development, the primary focus is very
much on the end-user engineering community and the
usability of the developed VRE. Consequently it is
end user led and focuses on lightweight unobtrusive
structures. Lessons learnt from applying these VRE
tools to this specific focused group will have benefits
for the wider science base using International User
Facilities. The project targeted two sets of problems
that require separate, but connected approaches.
• Human Interaction (Experimental Steering)
o the need for a mechanism/medium for
experiment steering, to discuss progress,
modify strategies, and to train and instruct
students
o these aspects are being pursued via the
provision of Access Grid (AG) functionality
at the remote sites and universities / home
• Software Interaction (Data Management)
o
o
2.1
the need for a mechanism/medium for
collaboratively analysing data and making
archival data, collected elsewhere or during
previous
experiments,
available
for
immediate side-by-side comparisons.
these activities involve embedding a set of
well defined web services within a portal
service framework using toolsets such as
uPortal [3].
Experimental Steering Function
Stress measurement often takes place at remote
sites and expert advice is often needed out-ofoffice hours. Unless the expert (e.g. PhD
supervisor) accompanies the experimenters (e.g.
PhD students) throughout, communications can
be inadequate leading to avoidable errors and
missed learning opportunities.
Intelligent
discussion, effective training and steering require
a combination of three modality streams on
screen:
o Group-based face to face contact, or at least
voice to voice (via AG)
o A shared view of the experimental
configuration (using AG)
o A common shared ‘tablet’ or ‘workspace’ to
visualise results from the Data Management
Function.
2.2
Data Management Function
Some logistical problems only become apparent
when the experimenter tries to mount the sample
on the instrument; these could be avoided by a
virtual dry-run ahead of time.
Once the
experiment has begun the software required to
assimilate the data may not be available at the
work-cell or remote facility (Figure 1) usually
because of computing, software or time
constraints.
Discussions at this point, involving project
supervisors and even industrial engineers based
on recently acquired and analysed real-time data
could add true value to the experiments,
especially if previous results can also be drawn
down for comparison.
In effect, all the
collaborators will have opportunities to access
and analyse the data and hence to offer their
opinions on the particular measurement strategy.
As a result the onus for experimentation and
analysis can be more evenly shared amongst the
group and a wider, multidisciplinary view
brought to bear on the experiment in a timely
fashion. Hence the learning curve for the PhD
students can be much steeper.
We aim to extend our present ontology to support the
more complex workflows and interactions that need
to take place in our multidisciplinary teams. It is
envisaged that this will lead to a cultural change in
the way experiments are undertaken.
Most
importantly, it will allow the experimenter to regain
the initiative. Moving away from pre-determined
experimental sequences to interactive experiments, in
which developments are monitored during the
experiment and strategies modified accordingly. This
project looks to tailor these toolkits for multi-site
engineering experiments. The project is investigating
the use of various common web portals to allow the
VRE project to deploy the Engineering Body Scanner
(EBS) [2] toolkit at multiple sites.
3. Analysis and Outcome of Experiment
Steering Trials
The culture of the meeting room has been altered to
accommodate the practical requirements of the endusers’ for this project. The interactions via the
multimedia resource (use of AG software) should not
be at the meeting room level but at the experimental
level, whereby the whole team can ‘meet’ together
bringing their own data, modelling predictions and
discuss and develop an evolving experimental
strategy with Grid middleware. This task is not one
of just teleconferencing, but rather a means of
involving extended multi-disciplinary groups in the
experimental steering process. It allows out-of-office
hours steering using home broadband networks to
link to the experimental site. We have analysed
various AG software to identify the best options
dependant on cost, ease of use and reliability
regarding future use within the materials science
community.
For the Experimental Steering Function we have
trialled Access Grid, focusing primarily on how best
to configure it to optimise HCI and usability. To this
end we have established our own ‘virtual venue’. Due
to the 24 hour nature of our experiments and the cost
and infrastructural implications it was deemed more
appropriate to use Access Grid predominantly on
computers with good quality webcams rather than via
specialist traditional dedicated and fixed Access Grid
studios. This is because firstly, for the experimenter,
involvement must be seamless with the practical
experimental function and secondly, because
academics may need to enter into dialogue at home
during unsociable hours. Connectivity between our
two functionalities is achieved through the use of a
shared virtual screen (“Shared Workspace”) on which
data analysed in the Data Function can be viewed on
the web portal through the use of a standard web
browser.
The initial trial of AG steering was between the
Manchester School of Materials, Daresbury
Laboratory and ISIS, Oxford. Common AG meeting
tools include:
1. inSORS [4],
2. AccessGrid ToolKit 2.4 (AGTk) [5],
3. Videoconferecing Tools & Robus Audio Tools
(vic&rat) [6]
4. Virtual Rooms VideoConferencing System
(VRVS) [7]
Each has its own advantages and disadvantages in
terms of the features provided, quality and cost.
Although vic&rat are two separate video and audio
applications, together they can considered as a basic
AG tool. vic&rat have a command-line interface
which requires users to know the multicast-unicast
bridge server before use. The combination of
command line interface and the need for a-priori
knowledge severely and negatively impact on vic&rat
as a general choice as an AG meeting tool.
VRVS, on the other hand, is a fully web and Appletbased AG tool using its own improved version of
vic&rat incorporated with its own Java proxy
applications. It allows almost anyone to join an AG
meeting behind a firewall network without any ports
having to be specially opened. Although VRVS can
be in many respects be considered an ideal tool,
limited communication between VRVS venues with
existing AG virtual venues has relegated its utility for
our purposes.
The choice between inSORS and AGTk can be
informed by investigating the following attributes and
comparisons discussed in Table 1:
a. Audio & Video communication network
Focusing on support for AG meetings using a
slow upload rate characteristic of home
broadband networks.
b. Ease of Use and Available Features
Focusing on the easiness and useful features
provided by the different AG tools
c. Reliability
Focusing on the stability of the “bridge server”
supported by the AG tools.
d. Support of Hardware Tools
Focusing on the wider range of hardware tools
particularly to webcam and sound card.
e.
Firewall Network
Support of network behind firewall routers
typical of large international experimental
facilities.
f.
Cost & Set-Up & Support
Focus on the cost and after sales support for
installation of AG tools.
Table 1: Comparisons between inSORS and AGTk
Aspects
(a)
(b)
(c)
(d)
inSORS
Audio
– supports 64Kb/s outgoing, ideal for
broadband upload speed.
– experiments indicated that it only supports
Linear-16 encoding incoming audio from
other AG tools
Video
– supports configurable video quality but a
minimum 128Kb/s outgoing, not ideal for
broadband upload speed.
There are a suite of features supported within
inSORS:
– IGMeeting runs in the background, allowing
other inSORS users to contact to set-up a
meeting as required.
– Meeting can be conducted by creating your own
meeting venue without needing to use any of
the pre-defined virtual venues.
– IGWhiteboard is a useful feature supporting
of the copy&paste of diagram from clipboard.
However, we’ve found the speed for pasting
clipboard contents a serious bottleneck for
upload and download speed.
– IGFile Sharing is useful during a discussion,
though the upload of the file uses up bandwidth
and reduces the whole meeting performance.
– ShareURL is an useful feature allowing one to
post a web page to another users’ computer
with single click of the button.
– IGChat not very useful as audio obviates need
for text-line chatting.
– The bridge servers offered by inSORS and
Manchester Computing have been found
reliable.
– However, the inSORS bridge server offered by
Manchester Computing runs version 1 which
can results incompatible with inSORS server
itself that runs version 2.
– Certain audio incompatibility issues have been
encountered between the bridge server used
inSORS and AGTk.
– The supports for video and audio hardware is
up to date.
AGTk
Audio (based on vic&rat)
– supports GSM encoding 24Kb/s outgoing
but NOT supported by inSORS client.
– supports Linear-16bit outgoing audio but it
will take up to 256Kb/s audio, not ideal for
broadband upload speed.
Video
– Configurable video quality with reasonable
of 64Kb/s, ideal for broadband speed.
– Meeting needed to pre-arranged, which is not
feasible in many of our experiment scenarios.
– Meeting must be conducted within a predefined virtual venue.
– The only built-in feature is text chat.
– No other built-in features unless users install
the plug-in themselves as part of AGTk.
– The only bridge server offered by Manchester
Computing used by AGTk can be unreliable
due to high traffic usage.
–
–
(e)
– inSORS works behind a firewall as long as the
port 554 is opened for port triggering to
forward packets to the host AG machine.
–
–
Heavily depends on vic&rat tools, which has
not been updated for a few years.
Wide range of hardware has not been
supported particularly in audio. No support
for USB audio devices.
AGTk’s performance behind a firewall
network can be variable. Commonly, port
forwarding of TCP/UDP port 10000-20000 is
required to open.
10,000 port opening can certainly be a serious
drawback for experimental sites with tight
network security.
(f)
– Education cost of £600 license is required per
portal.
– Installation is straightforward and configuration
found to be easy. After-sales support is
considered reliable and good technical services.
–
–
–
To expedite our trial, we have purchased a few copies
of inSORS for communication between experimental
and home broadband sites. The results of using
features in inSORS’s have been found satisfactory for
materials scientists, particularly the features of
“Shared Whiteboard” and “File Sharing”. The ease
of use of IGMeeting in that one can set-up a meeting
with other inSORS users without the need for a prearranged meeting had been proven a great advantage
over AGTk.
4. Analysis and Outcome of Data
Management
4.1 Choice of Web Portal (JSR-168
and WSRP)
Whilst the web portal concept can acts as an
efficient medium for our “Shared Workspace”
(discussion), to download/upload information
(data achiving/restore) or even to retrieve
previous experiment histories (playback virtual
experiments), it is imperative that our web portal
conform to a standard to allow efficient ways to
deploy, share and even reuse portlets from
various other VRE projects. It came to our
attention that JSR 168 is a Java Specification
Request (JSR) that establishes a standard API for
creating portlets.
We have investigated two main JSR-168
compliant web portals, GridSphere [8] and
uPortal [3] frameworks and come to the
following summary conclusions:
GridSphere
There is a large community who use GridSphere
as their main web portal service, but we found
the support and reliability of the software failed
to live up to expectations given our desire to run
and develop on Windows based platforms.
Nonetheless, GridSphere deployment on other
LINUX based projects such as GECEM at
Cardiff University [9], was successfully
achieved, albeit proving challenging at times.
We further note that the latest released Javabased framework GridSphere v2.1.4 is more
developed towards Linux-based than Windows,
making it unstable and failing to even get pass
the setup installation stage under the Windows
environments. Although the initial setup in
Free to download.
Set-up process can be complicated for novice
users. Results after installation process can
also be varying between machines and
networks.
No technical support apart from a advice from
mailing list, which can prolong the whole setup process.
Linux environments had been successful, portlet
deployment only proved stable if a lower version
of Java library and Apache web server was
installed on the host machine.
uPortal
This web portal has proven stable under our
rapid development of web services under
Windows and Linux environments. Its well
documented web-site is a valuable resource.
Furthermore, the developer’s release v3.0 has
been modified for the use of JSR-168 as a native
module, rather than using conventional Apache’s
Portlet-to-Channel adapter. This has given us
greater ease-of-use and reliability when using
this web portal for our development.
Web Service for Remote Portlets
(WSRP)
While XML-based web services have been used
in different API platforms to transfer data
between them, a new concept, Web Service for
Remote Portlets (WSRP), allows portlets to be
exposed as Web services [10]. The resulting web
service will be user-facing and interactive among
different web portals. Unlike traditional Web
services, WSRP will carry both application and
presentation logic that can be displayed by a
consuming portal. To the end user, remote
portlets will look like and interact with the user
just as local portlets would. Unfortunately,
WSRF is not yet an agreed standard and
therefore interoperation is not guaranteed.
Furthermore, it is still at an early stage of
development from certain software vendors, it is
therefore, difficult to judge and implement a realpluggable WSRP portlet. Although various
.NET 2 web portal libraries have the features to
allow implementation of Web Portal service, the
use of WSRP has not been implemented to allow
interoperability.
We are, however, closely
monitoring the development of WSRP and our
choice to use uPortal library that conforms to the
current WSRP standard will enable us to exploit
other WSRP modules when it is incorporated
within a wider range of software vendors’
standard.
Figure 2: Prototype ISME Web Portal
Materials
o
We have conducted a series of structured
interviews with material scientists following the
completion of a questionnaire in order to
ascertain which web services are required by the
material scientists. The interviews have been
conducted with members of differing roles and
levels of experience, namely, a Professor, a
project manager, a lecturer, an instrument
scientist and three PhD students. The principal
issues/requirements are summarised below:
o Communications concurrent with scene/data
visualisation is required. This will help to
identify experimental issues.
o The need for a shared desktop/workspace for
better collaboration.
This is especially
necessary to communicate problems and
share data.
o A data archive system is required, so that the
users are able to retrieve documents and
data, to have easy access to previous work,
with the experiments systematically
recorded.
o An electronic log book of the experiment
would be useful, very simple and easy to
use, including only pictures and text.
o A catalogue tool to organise the data
transfer.
o A tool to ensure the latest version of the
data.
o A tool to overcome the problem of sending
large datasets (GBytes) back university site
– maybe by using a very fast Internet
connection.
o AG meeting should be made more userfriendly, easier to set up at any time,
reliable, easy to use, portable, as a package,
not to require additional time to set-up.
o
4.2 Web Portlets
Scientists
for
o
Access to a powerful resource computer via
fast internet to analyse results quickly.
A project scheduling tool would be also
useful to plan the experiment and to keep a
diary during experiments.
Possibility to simulate the experiment in
advance, like a virtual experiment, so that
new students can get used to the procedure
and the facilities.
Based on the above summary outcomes, we had
developed a prototype ISME web portal as
shown in Figure 2 offering the required services:
o Error Handling tab: for debugging
purposes during this prototyping phase.
o News tab: to display daily news from
various news channels provided by uPortal.
o Data Related Services: Archive Data,
File Manager, Catalogue Tool, Virtual LogBook
These services relate to data archival and
management tasks.
The catalogue tool
allows materials scientists to manage and
save their experimental results in a set of
discipline categories of database format.
This will allow PhD supervisors or other
colleagues to easily access and acquire
information when needed. The Virtual LogBook is more a personal service where
experimenters can keep their notes and
hourly experimental results digitally on to
the centralised server for retrieval when
needed in future.
o Remote Processing Services: This
service aims to provide the material
scientists with the ability to connect
remotely to their local machine back at the
home university site and to launch different
useful application installed there, such as
o
o
ABAQUS, ImageJ, GSAS, OpenGini, Exact,
FORTRAN, MS Excel, MS Word etc. This
service ensures that the user is properly
authenticated into the remote host and gives
them the opportunity to use the software
applications they usually employ to visualise
data, analyse results, make conclusions etc.
Communication: Image, Video, Chat,
Shared
Desktop,
Message
Board,
AccessGrid.
This service allows materials scientists to
communicate to each other, for example,
sharing images and video on the web portal.
A common shared workspace with AG tools
can be used to visualise results from the
experiments via the multimedia resource,
whereby the whole team can ‘meet’ together
bringing their own data, modelling
predictions and discuss and develop an
evolving experimental strategy.
Miscellaneous:
Calendar,
Project
Scheduling, Virtual Experiments, Email
The calendar service is to support
experimental scheduling and also allows
PhD supervisors or co-workers to locate
specific experiments of a materials scientist.
Virtual Experiments can be undertaken
using a legacy application developed by the
Open University [11].
This service aims to provide the researchers
with a simulation tool of the experiments at
the remote site, which they can use prior
their visit to the facility to learn the
experimental process or even on-site in case
any problems arise.
We have shown the above prototype web portal to
materials scientists for initial feedback. The materials
scientists perform different roles at the university and
during the experiments. The analysis of the feedback
results showed that the wide range of web services
was appreciated and that no services were perceived
as lacking.
There are other services which can be improved and
the concepts of these services need to be clear so as
not to replicate any of the currently available
applications. For example,
o Virtual Log Book would require time stamps
on the experiments as an automatic feature to
provide an historical record of actions.
o Archive Tools need to be merged with the
Catalogue tool to reduce replication within the
web portal.
o The Calendar service must be linked to
experiments allocated by the experiment al
facility and should made public to allow other
colleagues to view timetables.
Some overlap between services has been identified in
this phase as well as some irrelevant services for the
experimenters such as Chat, Email and Video.
5. Future Work
We are closely collaborating with a wide-range of
material scientist users to determine and implement
our final phase of the ISME web portal. Feedbacks
from the first phase had given us the information to
prioratise and implement the services required by the
materials scientists. Technical lessons learnt from the
uPortal will also be documented as we believe this
maybe of interest to the VRE community.
At the same time, we are collaborating with
Manchester Computing to develop an AG Meeting
Notifications tools (based on vic&rat) to allow
meetings to be conducted instantly.
This open
source, licence-free and cost-free customisable AG
Meeting Notification tools will allow greater use
within VRE and materials scientist communities.
We have a Pan-Tilt-Zoom (PTZ) camera installed in
the experimental hutch to allow remote users to
control the static viewpoint. In addition we have also
developed a novel AG viewpoint: the Mobile-AG
node. The Mobile -AG gives remote users a first
person viewpoint and improved insight regarding the
mounting and positioning of a materials sample. It
uses a mobile camera system attached to the
experimentalist’s glasses so that their operations in
the experimental hutch can be broadcast to scientists
at remote sites. This gives remote team members an
insight into the local environment in a more flexible
manner than is available with static cameras. This
allows us to share views not otherwise available and
may help us to diagnose experimental problems with
the equipment, carry out repairs under instruction or
to allow remote users to offer advice about the
experimental set-up. At this stage of the project, we
are still investigating the full potential use of MobileAG used in the experiment hutch.
In summary, this project focuses on understanding
how VRE tools can assist large multi-site teams
undertake experiments at international facilities. Our
aim is to exploit and customise existing tools in such
a way that scientist can use them seamlessly and
effectively in undertaking experiments. So far we
have undertaken a small pilot study based around two
experimental facilities and one extended research
team. This project will be expanded to a wider range
of users with assessment criteria needed for evaluate
the prototype portal and services. We will have an
opportunity in July 2006 to have a full test-drive of
our AG tools and Web portal on the Daresbury 16.3
beamline using public access users, since this is to
become a public service beamline maintained partly
by the Manchester team. If this proves successful we
will examine the possibility of transferring the
approach to the new Diamond Light Source near
Oxford. This has created a unique opportunity to
embed and test our VRE tools with a large
community of new users to assess how these tools
support and impact the learning curve of new users.
6. References
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
K.T.W. Tan, D. Tsaneva, M. Daley, N.J. Avis
and P.J. Withers, Advanced Collaborative
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Nottingham
K.T.W. Tan, N.J. Avis, G. Johnson and P.J.
Withers, 2004, Towards a grid enabled
engineering body scanner. UK e-Science
Programme All Hands Meeting 2004,
Nottingham
uPortal – http://www.uportal.org
inSORS – Multimedia Conferencing &
Collaboration
Software,
http://www.insors.com
The Access Grid Project – a grid community,
http://www.accessgrid.org
Vic
&
Rat
–
http://wwwmice.cs.ucl.ac.uk/multimedia/software/
Virtual Room Videoconferencing System –
http://www.vrvs.org
GridSphere Portal – http://www.gridsphere.org
M. Lin, D.W.Walker, Y. Chen and J.W. Jones,
A Web Service Architecture for GECEM, AllHands Meeting, 2004, Nottingham
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http://www.oasis-open.org/committees/wsrp
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