Search

The Object Constraint Language (OCL) is commonly used for specifying additional constraints on models, in addition, to the ones enforced by the semantics of the models. However, a lot of practitioners and even researchers are reluctant in using OCL to some extent due to the lack of sufficient familiarity with OCL. To facilitate practitioners and researchers in specifying OCL constraints, we designed and developed a web-based tool called interactive OCL (iOCL) for interactively specifying constraints on a given model. The core idea behind iOCL is to present and display only relevant details (e.g., operations) of OCL to users at a given step of constraint specification process, in addition to helping modelers with its syntax. We evaluated iOCL using a real-world case study from Cancer Registry of Norway and the results showed that iOCL can significantly reduce the time required to specify OCL constraints and decrease the possibility of making syntactic errors during the specification process. Thus, we conclude that iOCL can facilitate the process of OCL constraint specification. Interested users can try iOCL at: http://iocl.zen-tools.com/ . [ABSTRACT FROM AUTHOR]

Abstract: The development and specification of interactive systems is a complex process. The use of notations, methods and their respective technological support is necessary for obtaining user interfaces in a purely engineering manner and not in a manner of craftsmanship, as has been the case thus far. In the field of Software Engineering, an interest is currently being taken in the Model-Driven Development (MDD) paradigm. MDD permits simplification and automation in the process of software development by defining models and transformations of those models. This paradigm can be successfully applied to the problem of obtaining Graphical User Interfaces (GUIs) from declarative models (Model-Based User Interface Development; MBUID). With the aim of solving the issue of obtaining a GUI by following a model-driven process, we propose a method, and a tool that implements that method called CIAT-GUI. In developing this tool we have made use of relevant technologies in the field of MDD such as EMF, GMF, ATL and MofScript. This proposed method, in contrast to other proposals existing in the literature, allows the visualization and modification of intermediate prototypes of the GUI and permits an executable GUI (in XAML language) to be obtained. Finally, an initial study was conducted with the aim of verifying the suitability of this approach and of the implemented tool, as well as assessing the perception of software engineers regarding its usefulness. [Copyright &y& Elsevier]

Abstract: The article presents an interactive model that increases the possibilities of exploration during the design process, increasing the number of ways to guide and build the design alternatives. The model considers a knowledge representation, based on the function–behaviour–structure framework that increases the number of relations between the representation levels. With this model, the designer can explore and converge the design space by means of rules that connect the abstraction levels. The model begins the synthesis from any level of abstraction; it explores the knowledge by means of pop-up menus, which can be freely selected by the user and makes it possible to go back to higher levels of abstraction during the synthesis. The paper starts with a brief survey of some of the most significant functional synthesis models and the knowledge schemes used, and then it describes the proposed model and its application to a design case. [Copyright &y& Elsevier]

Abstract: A new method of reverse engineering for fast, simple and interactive acquisition and reconstruction of a virtual three-dimensional (3D) model is presented. We propose an active stereo acquisition system, which makes use of two infrared cameras and a wireless active-pen device, supported by a reconstruction method based on subdivision surfaces. In the 3D interactive hand sketching process the user draws and refines the 3D style-curves, which characterize the shape to be constructed, by simply dragging the active-pen device; then the system automatically produces a low-resolution mesh that is naturally refined through subdivision surfaces. Several examples demonstrate the ability of the proposed advanced design methodology to produce complex 3D geometric models by the interactive and iterative process that provides the user with a real-time visual feedback on the ongoing work. [ABSTRACT FROM AUTHOR]

Abstract: This paper aims to develop a novel scheme for interactively deformable simulation with haptic feedback. All design modules are packaged and implemented, and the experiments are conducted to study the effects of interactive deformation. The study compares the experimental results of haptic feedback by different force propagation methods, according to the Hounsfield unit (HU) of volume data. Additionally, the estimation of optimal propagation depth is illustrated by using a mass–spring model. Finally, by using the proposed scheme, a haptic-based medical simulation system for brain surgery is investigated. The integration test results with haptic feedback scenarios show that the proposed development scheme can certainly comply with the design modules, and the deformable simulation and haptic force reach a good agreement. [Copyright &y& Elsevier]

Abstract: A virtual-reality simulator was developed for the training of Otolaryngology (Ear–Nose–Throat) surgical residents to perform myringotomy, a relatively common surgical procedure in which an incision is made in the eardrum mainly to treat middle-ear infections. The simulator presents the trainee with a three-dimensional (3D) virtual model of the ear that can be viewed through a mock surgical microscope consisting of a stereo visor mounted on a custom-designed stand. The trainee interacts with the virtual ear using a real myringotomy blade, the movements of which are tracked in real time using a stereo optical tracker. Interactions of the blade with virtual tissues are calculated and rendered on the visor using freely available physics and graphics software engines. Six experienced surgical residents and surgeons assessed the effectiveness of the simulator as a viable training tool by completing a questionnaire designed specifically for this study after using the simulator. Surgeons and residents were positively impressed by the simulator as a training tool and would recommend its use as part of training. [Copyright &y& Elsevier]

Abstract: As e-communities grow in both quality and quantity, their online users require more appropriate tools to suite their needs in such environments. Many such tools are not explicitly needed in real-world communities where humans directly interact with each other. Trust making and reputation ascription are among the most important examples of such tools. Humans often build trust relationships through interaction or recommendation, and are therefore able to ascribe relevant reputation to those they interact with. However, in online communities the process of trust making and reputation ascription is more complicated. In this paper, we address a special case of the trust making process where community users need to create bonds with those they have not encountered before. This is a common situation in websites such as amazon.com, ebay.com, epionions.com and many others. The model we propose is able to estimate the possible reputation of a given identity in a any new context by observing his/her behavior in other communities. Our proposed model employs Dempster–Shafer based valuation networks to develop a global reputation structure and performs a belief propagation technique to infer contextual reputation values. The preliminary evaluation of the proposed model on a dataset collected from epinions.com shows promising results. [Copyright &y& Elsevier]

Abstract: A main goal of special education is the teaching of skills needed for an independent life. Virtual worlds are a valuable tool for this, enabling users to train real-world tasks in a save environment. An intuitive interaction device for mentally handicapped users are props on a board, but until now their interaction space has been limited to the size of the board, whereas the training of realistic tasks requires the use of a large and complex environment, detailing different aspects of everyday life. We devised four navigation strategies for props on a board and tested them with mentally handicapped users. The most suitable strategy was implemented in an educational game teaching common tasks, which may even span multiple locations, such as shopping at the supermarket and then preparing a meal at home. A user study with 24 participants showed that the system enabled all of them to navigate through the virtual environment to complete given tasks and indicated that the system supports learning processes. With our system, mentally handicapped people will be able to train everyday tasks in realistic surroundings, using intuitive prop-based navigation and a navigation strategy tailored to their needs. [Copyright &y& Elsevier]

A novel instructional computer simulation that incorporates a dynamic analogy to represent Le Chatelier’s Principle was designed to investigate the contribution of this feature to students’ understanding. Two groups of 12th grade Chemistry students (n =15) interacted with the computer simulation during the study. Both groups did the same pre-instructional and simulation activities except one of the groups interacted with the analogical example in the simulation and the other group was asked to recall an analogy that was presented in the form of text and pictures. A statistical analysis of the tests administered at the end of the study suggested that analogies that are dynamic, interactive, and integrated in a computer simulation may have a stronger effect on learning outcomes than analogies which are presented in the form of text and static pictures. The implication of this study for science educators is that dynamic computer-based analogies can enhance student learning of unobservable phenomena in science. [Copyright &y& Elsevier]

Abstract: We have designed and implemented an interactive simulation system for training and treatment planning in orthodontics. Currently, both treatment planning, and the choice of a proper appliance model, are based exclusively on clinician expertise. Most orthodontists work by trial and error when estimating the loading conditions that will achieve the desired tooth movement. There is a strong need for computer methods that will enable them to make realistic visual predictions of the final positions of the teeth and the changes in shape that the dental arch undergoes. To validate our simulator, we used cephalometric measurements and dental cast data taken during one-year follow-up orthodontic treatments. The results demonstrated a closely degree of fit between experimental orthodontic treatments and simulated case studies. In addition to its use in therapy planning, we expect our simulator to be a useful environment for training, providing a means to explore the temporal evolution of planned treatments. [Copyright &y& Elsevier]

Abstract: In [P. Hancock, A. Setzer, Interactive programs in dependent type theory, in: P. Clote, H. Schwichtenberg (Eds.), Proc. 14th Annu. Conf. of EACSL, CSL’00, Fischbau, Germany, 21–26 August 2000, Vol. 1862, Springer, Berlin, 2000, pp. 317–331, URL citeseer.ist.psu.edu/article/hancock00interactive.html ; P. Hancock, A. Setzer, Interactive programs and weakly final coalgebras in dependent type theory, in: L. Crosilla, P. Schuster (Eds.), From Sets and Types to Topology and Analysis. Towards Practicable Foundations for Constructive Mathematics, Oxford Logic Guides, Clarendon Press, 2005, URL www.cs.swan.ac.uk/csetzer/ ] Hancock and Setzer introduced rules to extend Martin-Löf''s type theory in order to represent interactive programming. The rules essentially reflect the existence of weakly final coalgebras for a general form of polynomial functor. The standard rules of dependent type theory allow the definition of inductive types, which correspond to initial algebras. Coalgebraic types are not represented in a direct way. In this article we show the existence of final coalgebras in intensional type theory for these kind of functors, where we require uniqueness of identity proofs () for the set of states and the set of commands which determine the functor. We obtain the result by identifying programs which have essentially the same behaviour, viz. are bisimular. This proves the rules of Setzer and Hancock admissible in ordinary type theory, if we replace definitional equality by bisimulation. All proofs [M. Michelbrink, Verifications of final coalgebra theorem in: Interfaces as Functors, Programs as Coalgebras—A Final Coalgebra Theorem in Intensional Type Theory, 2005, URL www.cs.swan.ac.uk/csmichel/ ] are verified in the theorem prover agda [C. Coquand, Agda, Internet, URL www.cs.chalmers.se/catarina/agda/ ; K. Peterson, A programming system for type theory, Technical Report, S-412 96, Chalmers University of Technology, Göteborg, 1982], which is based on intensional Martin-Löf type theory. [Copyright &y& Elsevier]