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We present in this paper a web-based version of a Scrabble game, describing its architecture and some implementation details. This architecture makes possible a high degree of interactivity, so that the players perceive the game as being played in real-time. Furthermore, no client-side plug-in or applet isused. These properties are achieved by means of a carefully designed architecture that uses AJAX (Asynchronous JavaScript and XML) for data exchange. This architecture guarantees low load on the server, so complex computations relative to the game logic can be done in real-time. Moreover, data structures and algorithms were designed to efficiently access a custom Galician dictionary, which supports the game functionalities. We show in this paper how this data structures and algorithms provide an efficient method to create a Scrabble move generation algorithm. We also show how the combination of these with the architecture proposed provides a fully interactive web application that can handle complex calculations over a very large lexicon with real-time appearance.

This paper describe the new concepts of collaborative systems quality evaluation. There are identified structures of collaborative systems. The paper define the quality characteristics of collaborative systems. There are proposed a metric to estimate the quality level of collaborative systems. There are performed measurements of collaborative systems quality using a specially designed software.

Theoretical computer science has been occupied with formal methods since the beginning. It has had its share of challenges, though. Often, excessive additional work is required to re-specify applications precisely in a new formalism, so that they can be analyzed algorithmically. With more model-based software engineering, this may have changed. In many instances, specifications are now complete and updated throughout the systems development life-cycle, primarily to drive rather than to document the process. Thus, formal approaches have become more realistic. This paper looks at one experiment with automatic usability evaluation, based on a structured user interface specification. It shows that there are promising results ahead. Examples of automatic usability evaluation based on a widely-use user-interface specification language are presented. Benefits of formal specification cannot be reaped, however, unless this approach is bolstered by a purposeful design of the modeling techniques and languages themselves. Thus, some requirements of the formalisms for model-based usability engineering conclude the paper.

This paper presents the findings of a study on the acceptability in higher education of a Web 2.0 collaborative application, namely eLogbook. The latter offers several features for sustaining collaboration and supporting personal and group learning. It was introduced to students taking a laboratory course that spans over one semester and mainly consists of in-class group experiments. In this paper, we present eLogbook. We then describe our hypotheses as well as the qualitative and quantitative methods used to evaluate the usefulness and usability of eLogbook in a formal learning context. Finally, we discuss our findings and its implications.

Networked haptic cooperation entails direct interaction among users as well as joint manipulation of virtual objects. To increase the realism of both types of interactions, this paper introduces remote dynamic proxies. Remote dynamic proxies are second order dynamic representations of users at the remote peer sites. They are generated according to dynamics laws and are controlled by the user whom they represent through a virtual coupler. Hence, they move in a physically intuitive manner and do not suffer from position discontinuities due to network packet transmission limitations. The remote dynamic proxies are integrated into a distributed control architecture for networked haptic cooperation. An experimental comparison of the new controller to two recently proposed controllers demonstrates smoother rendering of contact between users, as well as stable cooperation for larger network delays.

As a consequence of various situational and personal factors, programmers use a variety of styles when performing software development and maintenance tasks. In this paper, we develop a contextual framework that links situational, task-oriented, and individual factors to a set of traits. These traits are expressed as behavioural modifiers, and thus, influence one's performance of tasks such as computer programming, as well as influencing the skills upon which programming is based (e.g., problem solving, planning). To demonstrate the use of the framework, we examine how risk-tolerance is influenced by contextual factors and show how this trait influences programming style. We also document some preliminary components of programming style.

Clustering algorithms are the core technique of data mining, machine learning, pattern matching, bioinformatics and a number of other fields. This paper proposes a new clustering method based on attribute partitioning and a novel data visualization method. In a nutshell, the idea for our method is based on two steps: 1) cluster data set using primary and secondary attributes of data; 2) map color stimulus spectrum to RGB color space and visualize clustering using the chromaticity diagram of J.C. Maxwell (Maxwell's triangle). The experiments show that the algorithm is very efficient. In addition it is simple and easy to implement. Our visualization algorithm aims at helping the user to get an overview of data as well as in prediction and decision making processes.

Some authors argue that it can be complicated to build systems with both usability and security, but the reality is that there is no real conflict between these two properties. Certainly, it takes more work to build systems that have the properties of usability and security, but in many cases it is a matter of doing just a good job not miracles. The purpose of this paper is to establish patterns that allow to align both usability and security aspects.

An incoming freshman student stops by your office because he/she has read that your research area is HCI and desires to work with you. As teachers and academic advisers, how should we assist our students in choosing courses that will be beneficial to their study of HCI, but that will also provide the breadth that undergraduate studies provide? How should we as researchers assist our students in developing skills that will be beneficial to conducting research in HCI? How should we as teacher-researchers ensure that our student graduate from our universities adequately prepared? The aim of this paper is to present the HCI curriculum, to present the rationale for students to gain training in certain HCI-related areas that also provide for the breadth required in an undergraduate degree program, and to also suggest ideas for future work.

This paper deals with the usage of Virtual Reality and Scenario Languages in the field of teleoperation: how to enable a group of teleoperators to control, in a collaborative way, groups of real robots, in turn collaborating with each other to achieve complex tasks; such tasks include inspecting a dangerous area or exploring a partially unknown environment. The main goal is to obtain efficient, natural and innovative interactions in such a context.We first present the usage of Collaborative Virtual Environments (CVE) to obtain a unified, simplified,virtual abstraction of distributed, complex, real robots. We show how this virtual environment offers a peculiar ability: to free teleoperators from space and time constraints. Then we present our original usage of Scenario Languages to describe complex and collaborative tasks in a natural and flexible way. Finally, we validate the proposed framework through our Teleoperation platform ViRAT.

In this paper we present an evaluation methodology of personalized delivery of multimedia resources in an e-learning platform that takes advantage of web 2.0 technologies and its standards, such as (i) streaming using RSS and Atom feeds, (ii) searching using meta-data search engine, (iii) delivering using ubiquitous computing and (iv) personalized learning. Our framework consists of the following phases: (1) tracking the preferred delivery mechanism for each student model, (2) measuring the effect of the semantic profile time window parameter, (3) clustering students models based on similarity metrics on the delivery preferences and (4) comparing the results between personalized and non-personalized delivery. One important aspect of our approach is the combination of personalization and the data driven extraction (via clustering) of the students models based on similarity metrics. Our experimental results show that personalized delivery increases the usage of e-learning materials and the percentage of reviewing multimedia resources if these materials are delivered in ways that fit students preferences.

Interventional Radiology is a rapidly expanding speciality using minimally invasive techniques to treat a multitude of clinical problems. Current work in progress aims to create an affordable virtual training tool to reduce training times and patient risk during a trainee practitioners learning cycle. The procedure of arterial catheterisation has been broken down into a number of subtasks, one of which requires an operator to locate the femoral artery pulse by palpation. This is performed in preparation for a needle insertion to allow the entry of a guide wire and catheter into the patient. This paper presents the current state of research into a unique solution for affordable haptic simulation of pulse palpation in a virtual environment.

The popularity of consuming multimedia content on mobile phones is increasing more and more, not only because of the availability of the technical infrastructure, but also because of the mobility in modern society. We are developing a mobile multimedia streaming application. The crucial factor for such applications in order to be adopted and successful is user acceptance. This paper presents the preliminary concept and design of a contextual mobile multimedia content usability study. The study is conducted within are search project on agile software development methodologies with special emphasis on Extreme Programming and continuous usability evaluation. Past work included satisfaction of the needs of end users by means of focusing on user-experience in all steps of the development process. To gain scientific relevant data, the careful design of a study is considered most important. The study which will be conducted in October 2008 will give insights into mobile HCI concerning the coherence of content types, consumption times, and consumption contexts.

In this paper we describe an automated system, and its attendant set of techniques and tools, that is able to generate novel multimedia experiences. Using existing online sources, external textual and multimedia repositories, and user preferences, the system builds a customized audio/visual experience for the user. We discuss one application in detail: News at Seven, an automatically generated, personalized news show. Beginning with a set of user preferences, the system is able to find relevant text, process that text, and supplement it with images, video, and blogger responses. The final output of the system is an online Flash presentation that uses animated avatars with generated speech and is modeled after traditional nightly news broadcast. We see this work as the beginning of an overall approach to machine-generated content.

This paper describes the design, development and user study of a text-to-speech system for reviewing email messages. The system retrieves messages, converts them to audio files, and facilitates transferring the messages to a portable listening device. This study reviews the efficacy of such a system and compares the users' ability to comprehend spoken audio messages verses written messages. According to the study the system was successful, but the user interest in the design was only moderate.