Conference advance program: click here
Invited Speakers
Two distinguished researchers have agreed to delivering invited speeches.
They are: Accepted papers
PaperID
Type | Abstract |
001
full |
Runtime GUI Generation from XML Conceptual Description
Stefano Levialdi, Emanuele Panizzi, Roberto Perugini Casoni
In the process of creation of a Graphical User Interface, three
different activities play as many important roles: the functionality design,
the graphical and layout design, and the implementation. Our work addresses
the problem of clearly separating such activities, enabling the
creation of a GUI without any strong knowledge of implementation aspects.
In our system, the GUI can be completely described by an XML
specification, within two XML files: the first one describes the structure
and the components of the interface, as well as their associated action
names, while the second keeps the graphical information such as layout,
colours, icon identifiers. Our system, developed in Java, reads these files
and merges the information contained therein into another XML file.
Missing information is substituted by default values. Then, our system
parses the resulting XML description and, using the Reflection technique,
instantiates the widgets, associates them to the specified functionalities
and produces a running GUI. Analysis of related work and of possible
applications is provided.
|
002
full |
Dynamic Euler Diagram Drawing
Peter Rodgers, Paul Mutton, Jean Flower
In this paper we describe a method to lay out a graph enhanced Euler diagram so that it looks similar to a previously drawn graph enhanced Euler diagram. This task is non-trivial when the underlying structures of the diagrams differ. In particular, if a structural change is made to an existing drawn diagram, our work enables the presentation of the new diagram with minor disruption to the user's mental map. As the new diagram can be generated from an abstract representation, its initial embedding may be very different from that of the original. We have developed comparison measures for Euler diagrams, integrated into a multicriteria optimizer, and applied a force model for associated graphs that attempts to move nodes towards their positions in the original layout. To further enhance the usability of the system, the transition between diagrams can be animated.
This work extends a static (non-dynamic) graph enhanced Euler diagram drawing method previously developed by the investigators. We apply the dynamic drawing method to diagrammatic reasoning proof sequences, an application area where new diagrams are generated automatically, without any known embedding.
|
005
tech |
Structural knowledge and language notational properties in program comprehension
Pablo Romero, Benedict du Boulay
Several studies have suggested that there are segments
of the code which programmers regard as key when undertaking
programming tasks such as program comprehension.
Exactly what segments of the code are regarded as key depends
on the organisation and structure of the programmer’s
knowledge of programs among other factors. The
theory of Programming Plans offers one model of programmer’s
structure of knowledge and a view about which segments
of code are key has been associated to this model.
The empirical studies reported in this paper compare
languages of different programming paradigms to explore
whether key segments of the code are associated to Programming
Plans regardless of the notational properties of
the programming language employed, or whether different
paradigms might be related to different models of structural
knowledge. Additionally, these studies consider a practical
programming task, program debugging, and a common
measure of programming performance, error spotting accuracy,
to support their claims about the relevance of key
segments of the code for program comprehension.
The findings of the studies reported here confirm the importance
of key segments of the code for program comprehension
when considering a practical programming task
such as debugging. These results also indicate that key
segments might be related to different models of structural
knowledge for different programming languages and that
their visibility might be enhanced by employing a sensible
secondary notation.
|
010
full |
A Layered Architecture for the Exploration of Heterogeneous Information Using Coordinated Views
Isabel F. Cruz, Yuan Feng Huang
In a real-world decision support application, users often
want to search data from various sources according to
some criteria, build a visualization based on the data being
retrieved, and use the visualization to explore the data.
With our approach, these activities are supported within the
same workspace. Views are dynamically created by binding
each data set to a visualization template according to the
user’s preferences. The resulting views are then arranged
into a larger coordinated view. In our layered architecture,
data flows through the layers becoming encapsulated inside
of metadata that describes the visual attributes being added.
This metadata determines both the individual views and the
dynamic interactions within a coordinated view. Dynamic
interactions are implemented using a mediated notification
services architecture
|
011
full |
The Expressiveness of Spider Diagrams Augmented with Constants
Gem Stapleton, Simon Thompson, John Howse, John Taylor
Spider diagrams are a visual language for expressing logical
statements. Spiders represent the existence of elements
and contours denote sets. Several sound and complete
spider diagram systems have been developed and it is known that
the spider diagram language is equivalent in expressive power to
monadic first order logic with equality. However, these sound and
complete spider diagram systems do not contain syntactic elements
analogous to constants in first order predicate logic. We extend
the spider diagram language to include constant spiders
which represent specific individuals and give formal semantics for
the extended diagram language. We then prove that this extended
system is equivalent in expressive power to the language of spider
diagrams without constants.
|
012
full |
Double trouble: Mixing quantitative and qualitative methods in the study of extreme programmers
Sallyann Bryant
Despite sparse and sometimes contradictory evidence, Extreme Programming
(XP) is currently growing in popularity as an alternative strategy for developing software.
This paper proposes a methodology for observational studies of one of XP’s
twelve practices – pair programming – including the analysis of verbalisations,
interactions and artefacts in order to improving our understanding of its cognitive
implications. In addition, a protocol for analysing pair programming behaviours
is included as a means of identifying the behavioural differences of those who
are more expert or novice at pair programming and understanding the effect of
pairing programmers of differing expertise. Initial results from a recent study using
this methodology are then presented.
|
014
full |
Champagne Prototyping: A Research Technique for Early Evaluation of Complex End-User Programming Systems
Alan F. Blackwell, Margaret M. Burnett, Simon Peyton Jones
Although a variety of evaluation techniques are
available to researchers of visual and end-user
programming systems, they are primarily suited to
evaluation of research systems. It is important to have
evaluation techniques suitable for real-world
programming environments, in order to satisfy realworld
product managers of the usefulness of proposed
new features. To help fill this gap, we present a new
evaluation technique, based in part on Cognitive
Dimensions and Attention Investment, called
“Champagne Prototyping”. The technique is an earlyevaluation
technique that is inexpensive to do, yet
features the credibility that comes from being based on
the real commercial environment of interest, and from
working with real users of the environment.
|
015
full |
Semantics of UML 2.0 Activities
Harald Stoerrle
The recent major revision of the UML has introduced
significant changes and additions. In particular,
the metamodel portion underlying Activity Diagrams has
been completely reengineered, with Activity being the central
concept, the successor of ActivityGraph in UML 1.5.
In this paper, a denotational semantics for Activities is de-
fined as a mapping from Activities into Procedural Petri nets. The semantics excludes data type annotations and all
features based on them, but includes all kinds of control
flow, including non well-formed concurrency and, particularly,
procedure calling.
|
016
full |
Rewarding Good Behavior: End-User Debugging and Rewards
Joseph R. Ruthruff, Amit Phalgune, Laura Beckwith, Margaret Burnett, Curtis Cook
Emerging research has sought to bring effective debugging devices to end-user programmers. This research has largely focused on how well such devices bring genuine "functional" rewards to end users. However, emerging models of programming behavior indicate that another, often ignored, type of reward##perceivable rewards##can play an equally vital role in how well debugging devices serve end users. Using an empirically evaluated fault localization device, this paper investigates the impact such perceivable rewards can have on end-user debugging. Our results indicate that perceivable rewards alone can significantly improve the effectiveness and understanding of end users performing debugging tasks.
|
017
full |
User Preference and Performance with UML Interaction Diagrams
Jennifer Swan, Dr. Maria Kutar, Dr. Trevor Barker, Dr. Carol Britton
During the requirements process it is of key importance that all representations used are clearly understood by those who must use them. Therefore it is essential to ensure that those representations are presented as effectively as possible. User preference is one area that may influence the effectiveness of the representations presented. This paper describes a study that was carried out to explore the relationship between user preference for UML sequence and collaboration diagrams. Results show that participants who preferred sequence diagrams showed improved performance when using sequence diagrams. This was true for preferences expressed both before and after the task. However, participants who did not prefer sequence diagrams showed an overall improved performance for both types of diagram over the group that preferred sequence diagrams.
|
019
tech |
Integrating a Zoomable User Interfaces Concept into a Visual Language Meta-tool Environment
Na Liu, John Hosking, John Grundy
Our experiences developing and evaluating a range of visual language environments, and those of others, suggest that visual languages often have major problems with lack of screen real estate. Multiple views are commonly used to solve this by allowing large systems to be modelled by breaking into smaller parts. However this approach has limitations and we have begun to explore the use of “Zoomable User Interfaces”, (ZUIs), for this type of application. We have added prototype ZUI facilities to Pounamu, a meta-tool we have developed for building multiple view visual language environments. We motivate the need for ZUIs in visual language tools, illustrate our ZUI extensions to Pounamu in use, and discuss our experiences to date in building and using these facilities.
|
021
full |
Gender: An Important Factor in End-User Programming Environments?
Laura Beckwith, Margaret Burnett
A human-centric issue that has not been considered in the design of end-user programming environments is whether gender differences exist that are important to the design of these environments. Ignoring this issue would miss the opportunity of enhancing the effectiveness of end-user programmers by incorporating appropriate mechanisms to support gender-associated differences in decision making, learning, and problem solving. This paper takes a first step toward building a foundation for investigating this issue by surveying gender difference literature from five domains from the perspective of possible implications for end-user programming. We present a taxonomy of this literature, and derive a number of specific issues for each element of the taxonomy (stated as hypotheses). This foundation provides a starting point for organized investigations into issues that may be important for making breakthroughs in the effectiveness of end-user programmers.
|
022
tech |
Pounamu: a meta-tool for multi-view visual language environment construction
Nianping Zhu, John Grundy, John Hosking
We describe a meta tool for specification and generation of multiple view visual tools. The tool permits rapid specification of visual notational elements, underlying tool information model requirements, visual editors, the relationship between notational and model elements, and behavioural components. Tools are generated on the fly and can be used for modelling immediately. Changes to the meta tool specification are immediately reflected in any tool instances. The tool has been used to generate a wide range of visual environments, and is designed for ready extension and integration with other tools.
|
023
tech |
CrawLogo: empowering end-users to program the Web
Kevin McGee, Johan Nilsson
In order to create Web-enabled applications that programmatically use the Web as an expressive medium, the current choice is largely between conventional programming languages that are difficult to learn and use – and less expressive alternatives. In order to address this issue, we have been developing CrawLogo, a Logo-inspired programming environment in which Web-elements are programmable, body-syntonic “Crawltures” that exist within a 5-dimensional Crawlture Geometry. In this paper we briefly summarize related work, describe the CrawLogo environment, some sample applications, and the initial response of end-user programmers who have successfully used it to build Web-enabled applications. We conclude with a discussion of some insights into the larger question of empowering end-user programming of the Web, the development of a Crawlture Geometry, and future research challenges.
|
024
tech |
CoOL-Room: Collaboration Oriented Learning Room
Maria De Marsico, Susanna Fratarcangeli, Stefano Levialdi, Leonardo Lombardo
This paper presents a system supporting synchronous distance multimedia interaction. Such systems require a number of tools to communicate, enforce collaboration awareness and maintain consistency of shared resources. Moreover, the kind of resource requirements, most of all in terms of bandwidth and communication distribution, call for a suitable communication infrastructure. After highlighting such requirements to provide virtual room facilities, we shortly analyze a number of existing systems. We then present CoOL-Room - Collaboration Oriented Learning Room, and the design and implementation solutions we have adopted.
|
026
tech |
Toward Usable Mixed Reality Authoring Tool: Case study AMIRE
Marjaana Träskbäck
Mixed reality (MR) applications are gaining wider interest in industry and in future the use of mixed reality will spread into various application fields. Currently the threshold for growing development is that authoring of MR applications consumes a lot of time and resources and current MR authoring environments are designed and restricted for dedicated experts only. In this paper we present the results of a user test of mixed reality authoring tool. The tool is build for non-programmers who are experts in their own field of expertise and who do not have programming background. The tool needs to be consistent with commonly used tools and use common user interface conventions. When working with MR tools the applications are usually 3D, but development occurs in an office environment from 2D screen, where the users have trouble perceiving the third dimension accurately. The screen should display the coordinate axis and origin of the grid on the screen. To get accurate 3D positioning for the objects, the tool have to support live picture authoring, where the user can observe the object from different angles.
|
028
full |
Effect lines for specifying animation effects
Yoshikazu Kato, Etsuya Shibayama, Shin Takahashi,
When we create a 2D animations on desktop with Macromedia Flashcite{flash}, Microsoft PowerPointcite{powerpoint} and so on, we give objects effects and their parameters, such as motion path, speed, moving time.
We use conventional interfaces like menues or dialog boxes at the time.
However the motion effects associated with each object are not explicitly displayed on the canvas so that the user must investigate the property of the object by opening a dialog box to see what animations are associated with the object.
Moreover, setting various parameters with menus and dialog boxes is troublesome because the user must set each parameter one by one.
On this motivation, we provide using textit{effect line} for setting the effect and parameters.
Effect lines are popular technique used in comics and cartoons.
Their depiction have some information of effect of objects, e.g. speed, length of path, degree of rotation, and so on.
It enables us to set effects and their parameters to objects only by doing simple gesture.
In addition, we can recognize the animation by displaying effect lines when editing it on edit screen.
On this motivation, we provide using textit{effect line} for setting the effect and parameters.
Effect lines are strokes depicting object's motion in motionless pictures, such as comics.
They have some information of motion of objects, e.g. speed, length of path, degree of rotation, and so on.
It is easy for users to draw them on edit screens on desktop with the conventional pointing devices.
Therefore we tried to use effect line as setting parameter method.
It enables us to set effects and their parameters to objects only by doing simple gesture.
Moreover, we can recognize what and how the animation and motions are by effect lines on the motionless frames.
|
035
full |
Header and Unit Inference for Spreadsheets Through Spatial Analyses
Robin Abraham, Martin Erwig
This paper describes the design and implementation of a unit and header
inference system for spreadsheets. The system is based on a formal model of
units that we have described in previous work. Since the unit inference
depends on information about headers in a spreadsheet, a realistic unit
inference system requires a method for automatically determining headers. The
present paper describes (1) several spatial-analysis algorithms for header
inference, (2) a framework that facilitates the integration
of different algorithms, and (3) the implementation of the system.
The combined header and unit inference system is fully integrated into
Microsoft Excel and can be used to automatically identify various kinds of
errors in spreadsheets. Test results show that the system works accurately and
reliably.
|
036
full |
Everyday Programming: Challenges and Opportunities for Informal Web Development
Mary Beth Rosson, Julie Ballin, Heather Nash
Semi-structured interviews were conducted with twelve
end users who develop and maintain web content for
diverse organizations. We recruited participants
recruited through referrals or webmaster contact
information. They were interviewed about their general
background and web projects, with an emphasis on tool
usage and problem-solving strategies. Our qualitative
analysis of the interview results offers a socio-technical
perspective on everyday programming, with an emphasis
on the complex interactions between end-users’ personal
history, organizational context, and tool use.
|
039
tech |
Parsing spatial graph grammars
Jun Kong, Kang Zhang
This paper presents a parser for a spatial graph grammar formalism, which integrates both the spatial and structural specification mechanisms in a single framework. By taking advantage of the spatial information, the parser performs in polynomial time with an improved parsing complexity over its non-spatial predecessor, i.e. the Reserved Graph Grammar.
|
040
tech |
On a spatial graph grammar formalism
Jun Kong, Kang Zhang
This paper presents a new graph grammar formalism, which integrates both the spatial and structural specification mechanisms in a single framework. In addition to nodes and edges, this formalism treats spatial constraints as a type of language constructs in the abstract syntax. With the extended expressive power, semantic and structural requirements can be intuitively specified through spatial notations. Equipped with a parser that performs in polynomial time with an improved parsing complexity over its non-spatial predecessor, i.e. the Reserved Graph Grammar, the formalism can be used for practical visual programming.
|
041
full |
Model Management Through Graph Transformation
guanglei song, kang zhang
Model management offers a higher level interface than current techniques for metadata management, and generic operators drastically reduce amount of programming for metadata applications. The interactive nature of generic model management operators inevitably demands an intuitive representation. This paper proposes a visual representation for model management operators based on graph transformation. Graph transformation formalisms, as the theoretic foundation of many visual programming languages, can formally represent model management operators by visual and intuitive expressions. By using graphical representations users can easily comprehend and manipulate the operators and desired outputs.
|
043
tech |
Computationally-Enriched ``Piles'' for Managing Digital Photo Collections
Daniel Bauer, Pierre Fastrez, Jim Hollan
Since numerous empirical studies have demonstrated that people make
extensive use of piles when managing collections of paper documents,
it is surprising that piling has not been more
extensively investigated as a technique to support managing and organizing
digital information.
As part of a larger research effort both to understand
the cognitive strategies people use in managing collections of digital
information in visual workspaces and to build a versatile
infrastructure of tools to support those strategies,
we have developed ``computationally-enriched piles'' which offer
task-specific behaviors in local regions of a multiscale
workspace. We describe these collection-management tools and
how their design was informed by observing people organizing
collections of personal digital photographs.
|
045
full |
Managing Duplicated Code with Linked Editing
Michael Toomim, Andrew Begel, Susan L. Graham
The task of managing duplicated code has occupied the minds of
programmers for the past 50 years. Although the use of programming
abstractions for avoiding duplication has been extensively developed,
studies show that programmers still produce software full of
duplicated code. We argue that this is due to unavoidable cognitive
costs of using language-based abstraction mechanisms##-functions,
methods, and macros##-that limit their application. We present Linked
Editing, a novel editor-based interaction technique for managing
duplication without explicit abstraction. We have built a prototype
editor that supports this technique, and have conducted a user study
that indicates that programmers using Linked Editing can achieve
results comparable to functional abstraction in a fraction of the
time.
|
046
tech |
JIVE: Java Interactive software Visualization Environment
Umberto Ferraro Petrillo, Giuseppe F. Italiano, Pompeo Faruolo, Giuseppe Cattaneo
JIVE (Java Interactive software Visualization Environment) is a
system for the visualization of Java coded algorithms and data
structures. It supports the rapid development and deployment of
interactive animations through the adoption of an object oriented
approach. JIVE introduces several significant innovations such as
a flexible multi-purpose distributed architecture and an original
visualization framework. JIVE adopts a distributed architecture
that leverages the capabilities of Java, CORBA and object oriented
programming to separate transparently the visualization layer from
the underlying communication layer. Therefore, it becomes possible
to use JIVE in a variety of scenarios ranging from debugging
algorithmic code to software visualization in Virtual Classrooms
environments. Moreover, JIVE uses a zoomable user interface for
representing animated algorithms: seamless visualization of both
small and large data sets is achieved by using semantic zooming.
Finally, JIVE comes with a collection of already animated data
types including data structures belonging to the Java standard
libraries and to the JDSL (Java Data Structures Libraries)
algorithmic libraries.
|
047
tech |
Virtual Workshops for Human-Centric Computing
Maria Francesca Costabile, Daniela Fogli, Giuseppe Fresta, Piero Mussio, Antonio Piccinno
Twenty years of visual languages research aimed at developing not only programming languages but also methodologies, techniques, and tools for design, formalization, implementation, and evaluation of computing environments that are easier to learn and to use by a broader user population. In this perspective, we focused on the study of Interactive Visual Languages and their use in the development of software environments to be used by a specific type of users, i.e. professional people such as engineers, geologists, medical doctors, etc. The research we have developed in this field, and the experience gained has brought us to develop software environments that are easier to learn and to use in a specific field of activity, but also allow their users to tailor them for better adapting to their needs, and to even create or modify software artefacts. The latter are defined activities of End-user development, to which a lot of attention is currently devoted by various researchers in Europe and all over in the world. The design methodology that we have developed is refined in this paper, giving insights emerging from our recent experiences, and emphasizing how it supports Human Centric-Computing and End-User Development.
|
049
tech |
Vivio – A System for Creating Interactive Reversible E-Learning Animations for the WWW
Dr. Jeremy Jones
Vivio is a system that makes it easier to create interactive reversible 2D vector based e-learning animations for the WWW. Vivio animations describe how the properties of graphical objects change as function of time or as the result of external events. Since Vivio animations follow the execution of a program, they can respond to user input and are, consequently, not limited to preset animation sequences. Vivio animations are compiled into a compact intermediate code which is normally executed by the Vivio player hosted in a web page. A key feature of the Vivio player is that it can play Vivio animations smoothly, in both forward and reverse directions.
|
050
full |
Six Learning Barriers in End-User Programming Systems
Andrew J. Ko, Brad A. Myers, Htet Htet Aung
As programming skills increase in demand and utility, the learnability of end-user programming systems is of utmost importance. However, prior research on learning barriers in programming systems has primarily focused on languages, overlooking potential learning barriers in the environment and accompanying libraries. To address this, a study of beginning programmers learning Visual Basic.NET was performed. This identified six types of learning barriers: design, selection, coordination, use, understanding, and information. These barriers inspire a new metaphor of computation, which provides a more learner-centric view of programming system design.
|
051
tech |
Message-Flow Programming in PdaGraph
Yael Kollet, Trevor Smedley
PdaGraph is an end-user component-based programming language for the PDA. In the first stage a data-flow visual programming language was designed but this was lacking an intuitive user interface and the connections between different parts of the program were not visible. To make PdaGraph suitable for end users, we designed a high-level component-based message-flow programming language and environment. To verify that the design is end-user friendly we conducted a usability study using a low fidelity paper prototype, which included one cycle of four usability tests, followed by an analysis and changes stage, and a second round of four usability tests to verify the modified prototype. During the study, feedback was obtained by videotaping the subject-system interactions and by using a cognitive dimensions questionnaire.
|
053
tech |
Model-based Specification of Virtual Interaction Environments
Augusto Celentano, Daniela Fogli, Piero Mussio, Fabio Pittarello
This paper discusses a model-based approach to the design of complex interaction environments like virtual worlds, mixed and augmented reality. The environment with which a user interacts is seen as a virtual environment in which a population of virtual entities, created and maintained active by a program interpreted by the computer, is present, and which can be described by specifying the behavior of the population. The specification of the behavior occurs along three dimensions: 1) programming languages to specify system computations; 2) user activity languages to specify user activities; 3) perceptual languages to deal with the physical characteristics of the messages from the machine to the user. These dimensions define an interaction modeling space which constitutes the frame in which the virtual environment is specified.
|
058
full |
A Suite of Metamodels as a Basis for a Classification of Visual
Paolo Bottoni, Antonio Grau
Metamodeling frameworks for the definition and management of
visual languages allow the implementation of visual environments
based on some abstract notion of visual entity and of relations
among them. We propose a suite of metamodels able to accommodate
most commonly used visual paradigms, built as progressive
specialisation of a root meta-meta model. This approach
facilitates the design and implementation of new, general purpose
as well as domain specific, visual languages by allowing the
progressive construction of language-independent service layers.
|
060
full |
Comprehension strategies of end-user programmers in an event-driven application
Susan Wiedenbeck, Alec Engebretson
Teachers may engage in end-user programming to support student learning or administrative activities associated with teaching. The objective of this research is to understand strategies used by teachers in program comprehension and to identify specific problems they face. A think-aloud study was conducted of teachers comprehending an event-driven application, consisting of a graphical user interface and the scripts controlling it. We found that end users followed a strongly top-down strategy and breadth-wise exploration of the application. Depth-wise exploration was observed in half the teachers. Teachers varied greatly in their motivations and persistence to dig deeply into the code. Problems of the teachers included difficulties comprehending the event-driven application, given the distributed nature of the code, and choosing appropriate inputs for testing it. The lack of visual highlighting also hindered the comprehension process.
|
061
full |
A Parsing Technique for Sketch Recognition Systems
Gennaro Costagliola, Vincenzo Deufemia, Giuseppe Polese, Michele Risi
Several disciplines require the support of computer-based tools for creating sketches during early design phases. Unfortunately, most computer programs cannot parse and semantically interpret handwritten sketches.
In this paper we present a framework for modeling sketch languages and for generating incremental parsers to recognize them. The underlying parsing technique addresses the issues of stroke clustering and ambiguity resolution in sketches.
We also present a workbench supporting the presented framework.
|
063
tech |
The Effects of Algorithm Visualizations with Storylines on Retention: An Experimental Study
C. Hundhausen, R. Patterson, J. Brown, S. Farley
Algorithm visualizations graphically illustrate how al-gorithms work. In prior ethnographic studies of a computer science course in which students were required to construct and present their own algorithm visualizations, we observed that visualizations based on storylines tended to stimulate increased audience interest and involvement. This observation, coupled with the empirical research that substantiates the value of stories as mne-monic devices, raises an interesting research question: Do visualizations with storylines actually help students remember the procedural behavior of an algorithm better than visualizations that do not involve storylines? To investigate this question, we conducted an experimental study that compared the memorability of algorithm descriptions involving differing degrees of spatial and ver-bal embellishment. The study failed to detect significant differences. We reflect on our lack of significant results, and suggest two alternative paths for future research into the value of story-based algorithm visualization.
|
064
tech |
Secure Visualization of Authentication Information: A Case Study
Roberto Tamassia, Sean Cannella, Michael Shin, Christian Straub, Dan Polivy,
The open nature of the web makes it possible to create
spoofed information which, to the casual observer, is indis-
tinguishable from valid information. Remedying the prob-
lem is complicated by the fact that, in practice, users may
not be willing or able to follow complicated procedures for
detecting online fraud. We introduce the concept of in-
teractive deterrence, a scheme that helps protect the user
against spoo ng attacks while requiring minimal active in-
teraction. We also present a case study on a working proto-
type of prooflets, a system for detecting visual forgery of web
content based on a novel distributed authentication scheme.
Our web integrity client for prooflets adopts the interactive
deterrence principle and provides the user with a simple and
e ective visual interface for the verification of the integrity
of content within web pages.
|
065
full |
End-users' Mental Models of Concepts Critical to Web Application Development
Jochen Rode, Mary Beth Rosson, Manuel A. Pérez-Quiñones
We report an empirical study of nonprogrammers' mental models regarding particular concerns in web application development such as input validation, database lookup, and master-detail relationships. The goal of the study was to understand how nonprogrammers think about the data and logic underlying a web application. In continuing work, we are using this understanding as a basis for the design of tools and development resources that are intuitive and easy to use. The current paper describes the empirical work that was done and discusses its implications for the design of end-user web development tools that could be used to develop web applications of intermediate complexity.
|
066
tech |
The Evolving User-Centered Design of the Algorithm Visualization Storyboarder
C. Hundhausen, J. Wingstrom, R. Vatrapu
The ALgorithm VIsualization Storyboarder (ALVIS) enables beginning and intermediate computer science students both to construct “low fidelity” (rough, unpolished) visualizations of the algorithms under study, and to present those visualizations to their peers and instructor for feedback and discussion. The original ALVIS software was a frail research prototype. We are using an iterative, user-centered design process to develop a public domain version of the software suitable for use in a “studio-based” computer science course. Through a series of empirical studies of both low and high fidelity prototypes of ALVIS, we have reevaluated the original design of ALVIS, and are presently in the process of making three key design changes: (a) the underlying scripting language is being redesigned for simplicity and ease of learning; (b) the interface for creating and placing graphical variables and spatial structures is being simplified and streamlined for ease of use; and (c) new features are being added that explicitly support storytelling.
|
067
tech |
Supporting Computational Visual Theories in Biology
George Chin Jr., Eric G. Stephan, Kyle R. Klicker, Abigail L. Corrigan, Heidi J. Sofia
At the Pacific Northwest National Laboratory, the Visual Modeling Environment for Biology (VMEB) is being developed to allow biologists to construct visual representations of scientific concepts and theories. Unlike existing scientific visual modeling environments, VMEB captures and manages visual concepts and diagrams in a computational form that may be transferred across sessions, shared among collaborators, linked to external data sources, and searched against to identify relevant or matching information. VMEB captures not only generated graphical objects and their spatial relationships, but also the underlying biological meaning of those objects as defined by biologists. The biological meanings are attached to their associated graphical objects and relationships in rules that are saved to a rules base. Using an inference engine, VMEB may then automatically identify and attach biological meaning to graphical objects and patterns as they are constructed if those objects and patterns match existing graphical rules in the rules base. The collection of graphical rules constitutes an underlying visual language built upon emerging user-defined symbols and concepts. As such, the visual language dynamically evolves along with the biological theory under development.
|
068
tech |
Visual Explanations of Your Actions on the Web
Henry Lieberman, Earl J. Wagner
Web sites have become more complex while the interface of the web browser itself has remained static. As people perform increasingly complex actions on the web, such as purchases involving multiple sites, they have questions about their transactions: ``what is that charge for?'', ``why hasn't my order arrived?'', ``this isn't what I ordered, is it?'' For answers, they turn to customer service. With process descriptions for user actions and web site reactions, however, a software agent working on the user's computer can retrieve information and answer simple questions like these.
We present Woodstein, a software agent that works with a user's web browser to explain a user's actions on the web. It supports the inspection of data items in ordinary web pages, and visualizes their history and the processes that created them. It tracks a user's action and retrieves related information on the same web site, and even other web sites, to provide an integrated view of the relevant processes and data.
|
072
tech |
Programming Autonomous Robots by Demonstration using Artificial Neural Networks
S.M. Best, P.T. Cox,
The use of Artificial Neural Networks (ANNs) to control autonomous robots has been quite extensively studied. Also, in recent years researchers have begun to investigate the notion of programming such robots using visual programming languages based on various programming and robot control models. Some of this work has focused on developing visual programming by demonstration (PBD) systems.
Here we extend the latter approach by proposing a visual PBD environment for autonomous robots based on ANNs. Within this environment, sensor-to-motor rules, called sensorimotor maps, are programmed by employing ANNs to match sensor outputs to actuator inputs. The goal is to create a programming environment in which the end-user is not required to have any knowledge of the underlying control model, ANN programming in this case. In this regard, the current proposal appears more promising than previous attempts using the subsumption model
|
073
full |
An Automatic Layout Algorithm for Lograph
O. Banyasad, P.T. Cox
We present a layout algorithm for the Lograph debugger which automatically rearranges a Lograph query graph at run time in response to the application of Lograph rules by the interpreter. The algorithm addresses certain cognitive issues, aiming to make the execution of query graphs more comprehensible. It incorporates a foresighted graph adjustment technique that improves the layout of a query by searching for data structure patterns and looking ahead in the execution. The look-ahead attempts to decrease the expected future changes in the layout by leaning the current layout towards one that would require less modifications in the next few execution steps. The execution of a program in the debugger can be observed as a smooth transformation to a solution graph from a query graph, the layout of which is created by the user.
|
077
full |
Reduction of Cognitive Load Through the Addition of High-Level Semantics to ReactoGraph
Simon Gauvin, Trevor Smedley
This research studies usability probems in ReactoGraph, a visual
programming language designed to simplify the development of graphical
user interfaces. Its design incorporates concrete representations of
interface controls and behavior but suffers from complexity in defining
message passing, inter-component data flow, and event handling. We
attempt to further simplify the use of ReactoGraph by considering
effects of tool design on cognitive abilites and introduce three
high-level semantic additions to the language. We describe these in the
context of cognitive load and discuss results of a small user study
that shows promise in their effectiveness.
|
078
tech |
A Specification Technique for Model Based Derivation of Speech Interfaces
Jari Peltonen, Samuel Lahtinen, Kai Koskimies
Speech recognition could be used more widely if there
were easy, more systematic, and preferably partly automated
means to define speech interfaces for applications.
Models used to describe the underlying concepts and
structures in a specified system can also be used to derive
vocabulary of a spoken language for the system. Thus, the
speech interface construction process can be automated
in these domains. In this paper we introduce a specification
technique that uses combination of statechart templates
and structural models for deriving spoken command
languages for the domains specified by the structural
models. The approach is applied to the derivation of a
spoken command language for editing UML class
diagrams, as defined by the UML metamodel.
|
079
tech |
JeCo, a Collaborative Learning Tool for Programming
Andrés Moreno, Niko Myller, Erkki Sutinen
The pair-programming activities in a classroom are
found to support learning of the novice students during
the first programming courses. However, there are
very few tools that could support pair or group
programming in distance education courses. We
present a concept of collaborative program
visualization and a tool to realize it, called JeCo that
can help the students to work together on a platform
that supports both collaborative authoring and
program visualization.
|
|
