Recognizing body poses using multilinear analysis and semi-supervised learning

This paper presents an approach to full-body human pose recognition using features extracted from stereo silhouettes via multilinear analysis in a semi-supervised learning framework. Inputs to the proposed approach are pairs of silhouette images obtained from wide baseline binocular cameras. Through multilinear analysis, low dimensional view-invariant pose coefficient vectors can be extracted from these stereo silhouette pairs. Taking these pose coefficient vectors as features, a recently proposed state-of-the-art semi-supervised learning method, Universum, is adopted for pose recognition. Experiment results obtained using real image data showed the efficacy of the proposed approach.     

An extension of UML for the modeling of WIMP user interfaces

The Unified Modeling Language (UML) [OMG, Unified Modeling Language Specification, Version 2.0, Technical Report, Object Management Group http://www.omg.org/technology/documents/formal/uml.htm, 2005] provides system architects working on analysis and design (A&D) with one consistent language for specifying, visualizing, constructing, and documenting the artifacts of software systems, as well as for the business modeling. The user interface (UI), as a significant part of most applications, should be modeled using UML, and automatic CASE tools may help to generate UIs from UML designs. In this paper, we describe how to use and specialize UML diagrams in order to describe the UIs of a software system based on WIMP (Windows, Icons, Menus and Pointers). Use case diagrams are used for extracting the main UIs. Use cases are described by means of user-interaction diagrams, a special kind of activity diagrams in which states represent data output actions and transitions represent data input events. Input and output interactions in the user-interaction diagrams help the designer to extract the UI components used in each UI. We obtain a new and specialized version of the use case diagram for the UI modeling (called UI diagram) and a class diagram for UI components—called UI-class diagram. The user-interaction, UI and UI-class diagrams, can be seen as the UML-based UI models of the system. Finally, UI prototypes can be generated from UI-class diagrams with CASE tool support. As case study of our technique, we will describe an Internet book shopping system.     

Building a user-based model for web executive learning systems — a study of Taiwan's medium manufacturing companies

Historically, business executives, among all company members, have the least opportunities to interact with computers. Executive information system is the only known mature information system dedicated to business executives. However, in the Internet era, computer-based tools have become essential for executives learning to cope with the competitive market. This paper focuses on an empirical study to build a user-based model for a web executive learning system (ELS) by describing the relationship between the learning preferences and content selection of business executives, and their computer usage, leadership style, and content awareness level. The study reached the following conclusions: (1) leadership style has strong influence on the learning style; (2) content awareness has a weak link to the content selections; and (3) user profile on computer usage provides useful clues at design level to meet the learning preference of business executives. The user profile on computer usage, taken from business executives of employee size between 50 and 200, reveals that (1) these executives are frequent computer users; (2) most of them are willing to give ELS a try; (3) they prefer learning after work; and (4) they are willing to spend, on average, 3 days to learn the web-based learning environment.     

Systematic selection and implementation of graphical user interface metaphors

This article begins with a discussion of what metaphors are and how they might be used in technology-based learning products' interfaces. It identifies two classes of metaphors: underlying and auxiliary. Next it presents a model (POPITS) for identifying the web of related associations inherent in metaphorical design. It then applies that model to two separate underlying metaphors, the book and the map, and shows what sorts of auxiliary metaphors are thus elicited. The article closes with a discussion of the demands of metaphorical interface design.     

Control centric approach in designing scrolling and zooming user interfaces

The dynamic systems approach to the design of continuous interaction interfaces allows the designer to use simulations, and analytical tools to analyse the behaviour and stability of the controlled system alone and when it is coupled with a manual control model of user behaviour. This approach also helps designers to calibrate and tune the parameters of the system before the actual implementation, and in response to user feedback. In this work we provide a dynamic systems interpretation of the coupling of internal states involved in speed-dependent automatic zooming, and test our implementation on a text browser on a Pocket PC instrumented with a tilt sensor. We illustrate simulated and experimental results of the use of the proposed coupled navigation and zooming interface using tilt and touch screen input.     

Computer based testing using “digital ink”: Participatory design of a Tablet PC based assessment application for secondary education

In this paper, we identify key challenges faced by computer-based assessment (CBA) in secondary education and we put forward a framework of design considerations: design with the students and teachers, select the most appropriate media platform and plan an evolution rather than a revolution of prior practices. We present the CBA application ‘MyTest’ which was developed using the participatory methodology We!Design, with the collaboration of 31 students and teachers. The application is targeted for the Tablet PC platform, provides “digital ink” capabilities and supports both closed-type and open questions, facilitating the transfer of traditional assessment practices to CBA. Both students and teachers were excited about the design sessions, and they asserted that they would rely more on educational software designed using this approach. The comparison of the ‘MyTest’ application with an assessment application developed with the same participatory methodology and the involvement of 40 undergraduate students revealed dissimilar expectations and needs of high school and undergraduate students that are often disguised or misinterpreted. A pilot evaluation of the application in real learning conditions was conducted with 31 students using Tablet PCs and with 37 students using traditional PCs. Interestingly, the Tablet PC platform rendered the ‘MyTest’ application more useful and usable to the students, validating our claims.     

Designing and developing a language environment for second language writers

This paper presents a field study carried out with learners who used a grammar checker in real writing tasks in an advanced course at a Swedish university. The objective of the study was to investigate how students made use of the grammar checker in their writing while learning Swedish as a second language. Sixteen students with different linguistic and cultural backgrounds participated in the study. A judgment procedure was conducted by the learners on the alarms from the grammar checker. The students’ texts were also collected in two versions; a version written before the session with the grammar checker, and a version after the session. This procedure made it possible to study to what extent the students followed the advice from the grammar checker, and how this was related to their judgments of its behavior.The results obtained demonstrated that although most of the alarms from the grammar checker were accurate, some alarms were very hard for the students to judge correctly. The results also showed that providing the student with feedback on different aspects of their target language use; not only on their errors, and facilitating the processes of language exploration and reflection are important processes to be supported in second-language learning environments.Based on these results, design principles were identified and integrated in the development of Grim, an interactive language-learning program for Swedish. We present the design of Grim, which is grounded in visualization of grammatical categories and examples of language use, providing tools for both focus on linguistic code features and language comprehension.     

Exploring the potential of computer and video games for health and physical education: A literature review

This study aims at critically reviewing recently published scientific literature on the use of computer and video games in Health Education (HE) and Physical Education (PE) with a view: (a) to identifying the potential contribution of the incorporation of electronic games as educational tools into HE and PE programs, (b) to present a synthesis of the available empirical evidence on the educational effectiveness of electronic games in HE and PE, and (c) to define future research perspectives concerning the educational use of electronic games in HE and PE. After systematically searching online bibliographic databases, 34 relevant articles were located and included in the study. Following the categorization scheme proposed by [Dempsey, J., Rasmussen, K., & Lucassen, B. (1996). The instructional gaming literature: Implications and 99 sources. University of South Alabama, College of Education, Technical Report No. 96-1], those articles were grouped into the following four categories: (a) research, (b) development, (c) discussion and (d) theory. The overviewed articles suggest that electronic games present many potential benefits as educational tools for HE and PE, and that those games may improve young people’s knowledge, skills, attitudes and behaviours in relation to health and physical exercise. Furthermore, the newly emerged physically interactive electronic games can potentially enhance young people’s physical fitness, motor skills and motivation for physical exercise. The empirical evidence to support the educational effectiveness of electronic games in HE and PE is still rather limited, but the findings present a positive picture overall. The outcomes of the literature review are discussed in terms of their implications for future research, and can provide useful guidance to educators, practitioners and researchers in the areas of HE and PE, and to electronic game designers.     

Evaluating student response to WeBWorK, a web-based homework delivery and grading system

As the use of web-based homework delivery and checking systems expands, we have greater need to evaluate how students engage with these systems and how changes in the systems influence student behavior. Reported here is the assessment of WeBWorK, an open-source web-based homework program used largely in postsecondary math and science courses, with recent extension to high school courses. WeBWorK draws from a large library of problems to generate individual assignments and provides immediate feedback about correctness of students’ answers. WeBWorK allows entries in multiple choice, formula and numerical formats. The entries recorded by the system create an extensive database of student interactions with the system.In our two-part study, we (1) review 2387 student surveys about WeBWorK in three semesters across a range of mathematics courses and (2) test a model designed to classify student responses to system feedback, permitting a fine-grained analysis of the system’s records at the keystroke level for a cohort of 96 Calculus I students.Based on this data, our goals are, first, to understand how students use the system and respond to its feedback; second, to analyze the impact of upgrades to the system interface on student users, and third, to evaluate the efficiency of training raters to classify student records.We find that the introduction of new features to the WeBWorK interface (improvements generated by our initial assessment) were welcomed by most students and reduced the overall number of submitted errors by half by the third year of the study. Importantly, the interface improvements reduced the number of errors that were not pedagogically useful. We also find that our error classification model, called here the Student Response Model, was a good fit for our student sample, as reflected by inter-rater reliability of three raters who coded the student records. In sum, our error classification model appears to be useful for analyzing formula entries. To make this assessment model widely available, we designed a system of exercises to train raters to classify student response files for WeBWorK and similar web-based systems.     

The theatre through the computer

There is a long history of the theatre being used with educational purposes. Now the evolution of multimedia resources provide an opportunity to implement theatre through the computer. Although software for the production of multimedia stories exist, they give little attention to the necessary interface aspects required for a virtual theatre implementation. The objective of this work is to present the Theatre in the Computer (TC); software especially developed for the education of children. This software can be used to produce and to distribute plays through the Internet. The educational possibilities of TC are discussed here.     

Young children’s ability to use a computer mouse

Because there is little empirical data available on how well young children are able to use a computer mouse, the present study examined their proficiency in clicking on small objects at various positions on the screen and their skill in moving objects over the screen, using drag-and-drop and click-move-click. The participants were 104 children from Kindergarten 2 and Grade 1. The results show that children in Kindergarten 2 clicked and moved slower than children in Grade 1. Nearly all of the children were able to click within 3 mm horizontally and 6 mm vertically from the centre of a 3 mm target. The findings also demonstrate that in educational software drag-and-drop is the most appropriate movement procedure as it was found to be faster than click-move-click and resulted in fewer interaction errors. Interesting differences between horizontal and vertical movements were found. It is concluded that young children are generally well capable of using a mouse to operate educational software, making this a suitable input device for such applications.     

A case study on the design of learning interfaces

The design of educational software interfaces is a complex task, given its high domain dependency and multidisciplinary nature. It requires that teachers’ knowledge and pedagogical beliefs be incorporated into the interface, posing a challenge to both teachers and designers, as they have to act as partners from the earliest phases of the process, sharing their knowledge. The present work investigates the strategies designers used when paired with experienced teachers, to design two interfaces on chemistry, evaluating how designers work with subjects they know little about, in the initial phases of the design process. Our observations demonstrate that although experienced and non-experienced designers use different strategies to couple with the design task, both approached the task in a depth-first manner. These results should not be generalized, because few subjects were investigated, but point to the importance of being familiar with the knowledge domain – which poses a challenge for designers.     

Between the lines: documenting the multiple dimensions of computer-supported collaborations

This paper discusses the development of a documentation technique for collaborative interactions. We describe the original version of the technique as used for a single learner collaborating with a software based learning partner; the second generation of the technique, which required adaptation for application to the analysis of group use of multimedia; and finally the current variation, which is being used to record young children using digital toys and associated software. Particular attention is paid to the way in which the original approach has been adapted in order to accommodate learning contexts that involve technology beyond the desktop computer. We explore some of the challenges these different learning situations pose for those involved in the evaluation of collaborative learning and suggest that tried and tested techniques can be adapted and re-used, provided that the foci of interactivity are clearly specified and the appropriate data sources identified.     

Finding a way to usability: procurement of a taxi dispatch system

Despite the extensive work on human–computer interaction regarding methods of involving users and designing for high degrees of usability, there is surprisingly little published on how procurer organizations understand, reason about, and require usability. This study focuses on how one taxi company dealt with usability requirements when procuring a new dispatch system. We have conducted ten interviews with various stakeholders in the company and analyzed related documentation in order to discover the process. The case shows how the concept of usability matured during over time. The taxi company dealt with requirement elicitation by developing prototypes in small reference groups. They did no formal analysis of the operators cooperation with each other at the operator central, but they did include experienced users, which created implicit scenarios. The supplier company did not focus on the efficiency of the operators or, for that matter, the cooperative demands of the operator central in their original design, which became evident when the procurer organization requested a redesign that emphasized user tasks. This indicates, on one hand, the extent to which procurers must understand usability and cooperation to procure good systems design and, on the other hand, the extent to which designers must understand business and activity processes in order to design good systems.     

Interactivity in human–computer interaction: a study of credibility, understanding, and influence

Advancements in computer technology have allowed the development of human-appearing and -behaving virtual agents. This study examined if increased richness and anthropomorphism in interface design lead to computers being more influential during a decision-making task with a human partner. In addition, user experiences of the communication format, communication process, and the task partner were evaluated for their association with various features of virtual agents. Study participants completed the Desert Survival Problem (DSP) and were then randomly assigned to one of five different computer partners or to a human partner (who was a study confederate). Participants discussed each of the items in the DSP with their partners and were then asked to complete the DSP again. Results showed that computers were more influential than human partners but that the latter were rated more positively on social dimensions of communication than the former. Exploratory analysis of user assessments revealed that some features of human–computer interaction (e.g. utility and feeling understood) were associated with increases in anthropomorphic features of the interface. Discussion focuses on the relation between user perceptions, design features, and task outcomes.     

The Daktari: An interactive,multi-media tool for knowledge transfer among poor livestock keepers in Kenya

This article describes the findings from the assessment of a touch-screen, multi-media learning program on livestock health and production: The Daktari. The program was tested on a sample of 62 livestock keepers in the Nairobi slums of Kariobangi and Kibera. The study examined prior knowledge regarding three livestock diseases (liver fluke, mastitis and mange) and compared this to newly acquired knowledge after exposure to the software. The results demonstrated a significant difference between pre- and post-knowledge assessments confirming that use of the program led to learning. Learning occurred among a variety of demographic/social groups (i.e. age, gender and education) with a range of abilities. Indeed, by utilising an audio–visual interface developed with relevant content for the population in question, it was found that the program could support and enhance participant understanding of livestock disease causation, diagnosis, treatment and prevention.     

What is important in electronic textbooks for students of different achievement levels?

This paper reports the findings of a study that explored which characteristics of electronic textbooks correlated with knowledge acquisition by learners of different achievement levels. The study was carried out on 35 units of electronic textbooks that were studied by 19 high-achieving and 19 low-achieving students in four Estonian schools. The low-achieving students profited from clear instructions, familiar icons, examples, and answering from the keyboard. The high-achieving students benefited from key-combinations, menus with different levels, the Internet, analogies and lower density of terms in the content of the material. In electronic textbooks, not only the content, but also the design of the software, should be different for learners with a different achievement level.     

Using animations and visual cueing to support learning of scientific concepts and processes

The purpose of the study is to investigate the potential benefits of using animation, visual cueing, and their combination in a multimedia environment designed to support learners’ acquisition and retention of scientific concepts and processes. Undergraduate participants (N = 119) were randomly assigned to one of the four experimental conditions in a 2 × 2 factorial design with visual presentation format (animated vs. static graphics) and visual cueing (visual cues vs. no cues) as factors. Participants provided with animations retained significantly more concepts than their peers provided with static graphics and those afforded visual cues learned equally well but in significantly less time than their counterparts in uncued conditions. Moreover, taking into consideration both learning outcomes and learning time, cued participants displayed more instructional efficiency than their uncued peers. Implications and future directions are discussed.     

A usability comparison of PDA-based quizzes and paper-and-pencil quizzes

In the last few years, schools and universities have incorporated personal digital assistants (PDAs) into their teaching curricula in an attempt to enhance students’ learning experience and reduce instructors’ workload. One of the most common uses of PDAs in the classroom is as a test administrator. This study compared the usability effectiveness, efficiency, and satisfaction of a PDA-based quiz application to that of standard paper-and-pencil quizzes in a university course. Effectiveness was measured as students’ quiz scores and through a mental workload questionnaire; efficiency was the time it took students to complete each quiz; and satisfaction was evaluated using a subjective user satisfaction questionnaire. The study showed the PDA-based quiz to be more efficient, that is, students completed it in less time than they needed to complete the paper-and-pencil quiz. No differences in effectiveness and satisfaction were found between the two quiz types. Computer anxiety was not affected by the quiz type. For these reasons, as well as other advantages to both students (e.g., real-time scoring) and teachers (e.g., less time spent on grading), PDAs are an attractive test administration option for schools and universities.