Mobile Devices as Props in Daily Role Playing

Mobile devices such as cameras or mobile phones can be used as props; actively to convey a specific impression to people in the vicinity and to feel better when interacting with them. Based on field studies and interviews, three aspects of users acting with mobile devices are described: warm versus cold devices; how a mobile device conveys a specific impression by association to similar devices and specific situations of use; and how the characteristics of a mobile device may open or restrict the body language of the user.     

Energy-performance trade-offs for spatial access methods on memory-resident data

The proliferation of mobile and pervasive computing devices has brought energy constraints into the limelight. Energy-conscious design is important at all levels of system architecture, and the software has a key role to play in conserving battery energy on these devices. With the increasing popularity of spatial database applications, and their anticipated deployment on mobile devices (such as road atlases and GPS-based applications), it is critical to examine the energy implications of spatial data storage and access methods for memory resident datasets. While there has been extensive prior research on spatial access methods on resource-rich environments, this is, perhaps, the first study to examine their suitability for resource-constrained environments. Using a detailed cycle-accurate energy estimation framework and four different datasets, this paper examines the pros and cons of three previously proposed spatial indexing alternatives from both the energy and performance angles. Specifically, the Quadtree, Packed R-tree, and Buddy-Tree structures are evaluated and compared with a brute-force approach that does not use an index. The results show that there are both performance and energy trade-offs between the indexing schemes for the different queries. The nature of the query also plays an important role in determining the energy-performance trade-offs. Further, technological trends and architectural enhancements are influencing factors on the relative behavior of the index structures. The work in the query has a bearing on how and where (on a mobile client or/and on a server) it should be performed for performance and energy savings. The results from this study will be beneficial for the design and implementation of embedded spatial databases, accelerating their deployment on numerous mobile devices. Received: November 11, 2001 / Accepted: March 12, 2002 Published online: November 14, 2002 This paper is a significantly extended version of preliminary work that appeared in the Proceedings of the Very Large Databases (VLDB) 2001 Conference. The extensions include (i) a comparison of indexing alternatives carrying out the operations in a brute-force manner; (ii) observations showing that datasets do play a role in power consumption; (iii) architectural solutions to address the cache and memory hotspots for energy; and (iv) benefits when off-loading the work to a server over a wireless medium compared to doing everything on the handheld device.     

Adaptive target recognition

Target recognition is a multilevel process requiring a sequence of algorithms at low, intermediate and high levels. Generally, such systems are open loop with no feedback between levels and assuring their performance at the given probability of correct identification (PCI) and probability of false alarm (Pf) is a key challenge in computer vision and pattern recognition research. In this paper, a robust closed-loop system for recognition of SAR images based on reinforcement learning is presented. The parameters in model-based SAR target recognition are learned. The method meets performance specifications by using PCI and Pf as feedback for the learning system. It has been experimentally validated by learning the parameters of the recognition system for SAR imagery, successfully recognizing articulated targets, targets of different configuration and targets at different depression angles.     

Socio-Cognitive Factors in the Acquisition and Transfer of Knowledge

Within cooperative learning great emphasis is placed on the benefits of ?two heads being greater than one?. However, further examination of this adage reveals that the value of learning groups can often be overstated and taken for granted for different types of problems. When groups are required to solve ill-defined and complex problems under real world constraints, different socio-cognitive factors (e.g., metacognition, collective induction, and perceptual experience) are expected to determine the extent to which cooperative learning is successful. Another facet of cooperative learning, the extent to which groups enhance the use of knowledge from one situation to another, is frequently ignored in determining the value of cooperative learning. This paper examines the role and functions of cooperative learning groups in contrast to individual learning conditions, for both an acquisition and transfer task. Results for acquisition show groups perform better overall than individuals by solving more elements of the Jasper problem as measured by their overall score in problem space analysis. For transfer, individuals do better overall than groups in the overall amount of problem elements transferred from Jasper. This paradox is explained by closer examination of the data analysis. Groups spend more time engaged with each other in metacognitive activities (during acquisition) whereas individuals spend more time using the computer to explore details of the perceptually based Jasper macrocontext. Hence, results show that individuals increase their perceptual learning during acquisition whereas groups enhance their metacognitive strategies. These investments show different pay-offs for the transfer problem. Individuals transfer more overall problem elements (as they explored the context more) but problem solvers who had the benefit of metacognition in a learning group did better at solving the most complex elements of the transfer problem. Results also show that collective induction groups (ones that freely share) – in comparison to groups composed of dominant members – enhance certain kinds of transfer problem solving (e.g., generating subgoals). The results are portrayed as the active interplay of socio-cognitive elements that impact the outcomes (and therein success) of cooperative learning.     

Model-based detection,segmentation, and classification for image analysis using on-line shape learning

Detection, segmentation, and classification of specific objects are the key building blocks of a computer vision system for image analysis. This paper presents a unified model-based approach to these three tasks. It is based on using unsupervised learning to find a set of templates specific to the objects being outlined by the user. The templates are formed by averaging the shapes that belong to a particular cluster, and are used to guide a probabilistic search through the space of possible objects. The main difference from previously reported methods is the use of on-line learning, ideal for highly repetitive tasks. This results in faster and more accurate object detection, as system performance improves with continued use. Further, the information gained through clustering and user feedback is used to classify the objects for problems in which shape is relevant to the classification. The effectiveness of the resulting system is demonstrated in two applications: a medical diagnosis task using cytological images, and a vehicle recognition task. Received: 5 November 2000 / Accepted: 29 June 2001 Correspondence to: K.-M. Lee     

Negotiating Use: Making Sense of Mobile Technology

This paper is based on a study of the ways in which a group negotiated the use of a new mobile technology. The group was made up of ski instructors who, during a one-week ski trip, were equipped with a mobile awareness device called the Hummingbird. The group was studied using ethnomethodologically inspired qualitative methods, with the focus on the group members’ different views of the Hummingbird’s intended use. Negotiations of use occurred using two methods: talk and action. The users negotiated issues such as where and when to use the technology, and whether to consider the Hummingbird a work tool or a gadget for social events. Further, the empirical results clearly show how negotiations of new, mobile technology differ from stationary technology.     

The Mobile Phone: An Identity on the Move

This paper analyses the shifting identity of the mobile phone in the light of research carried out in 1996 on a representative population sample from five major European countries: Italy, UK, France, Germany and Spain. A total of 6609 people were interviewed by means of a telephone survey. The mobile phone emerged as a charismatic technology compared to other mobile technologies (laptop and car phone) and as a leading technology that, in just a few years, has appropriated 11% of total telephone traffic. It has “dragged” its widespread presence and amount of use from the workplace to the domestic sphere, although in Italy, where it has had greatest success, its widespread use has been detached from its use in the workplace. Another emerging result is that the use of the mobile phone is not correlated to strong residential mobility in individuals.     

Using Handheld Devices in Synchronous Collaborative Scenarios

In this paper we present a platform specially designed for groupware applications running on handheld devices. Common groupware platforms request desktop computers as underlying hardware platforms. The fundamentally different nature of handheld devices has a great impact on the platform, e.g. resource limitations have to be considered, the network is slow and unstable. Often, personal data are stored on handheld devices, thus mechanisms have to ensure privacy. These considerations led to the QuickStep platform. Sample applications developed with QuickStep demonstrate the strengths of the QuickStep environment.     

What are a Location’s “File” and “Edit” Menus?

The promise of mobile devices lies not in their capacity to duplicate the capabilities of desktop machines, but rather in their promise of enabling location-specific tasks. One of the challenges that must be addressed if they are to be used in this way is how intuitive interfaces for mobile devices can be designed that enable access to location-specific services usable across locations. We are developing a prototype mobile valet application that presents location-specific services organised around the tasks associated with a location. The basic elements of the interface exploits commonalties in the way we address tasks at various locations just as the familiar “file” and “edit” menus in various software applications exploit regularities in software tasks.     

Managing One’s Availability to Telephone Communication Through Mobile Phones: A French Case Study of the Development Dynamics of Mobile Phone Use

This paper provides empirical results concerning the negotiation of access and joinability by mobile phone users. It shows how access is embedded in a gift-giving economy (giving one’s number for example). It also shows that the more users make themselves available on the mobile phone, the more their mobile phone traffic increases (both incoming and outgoing). This remarkable result is discussed in terms of the reciprocity involved in the management of mobile phone relationships.     

Patterns of Mobile Interaction

The design of systems for mobile scenarios covers a wide range of issues, ranging from mobile networking to user interface design for mobile devices. Mobile applications often run distributed on several connected devices, used by many users simultaneously. Considering all issues related to mobile scenarios, a designer might be overwhelmed. As a solution, we propose a specific kind of design patterns which we call mobility patterns, derived from successful mobile applications. They allow a designer to re-use design elements as building blocks in their own designs. After describing the idea of mobility patterns, we give a brief overview of patterns we have identified so far. Two patterns are described in more detail with the help of our research platforms QuickStep and Pocket DreamTeam.     

New Active Tools for Supporting Narrative Structures

Constructing stories is a type of playing that involves mobilizing the storyteller’s imagination and finding original ways to convey narrative intentions. When a child invents a story, there is a natural interaction with the local environment and the use of various means of expression. We adopted a user-centered approach to design POGO, a playful environment which utilizes the child’s physical environment and sensory modalities. Pogo is a system of active tools that enable children to create stories by connecting physical and virtual environments. By providing children with the possibility of capturing and manipulating images and various media, and combining them in sequential form, Pogo triggered new strategies in the construction of narrative logic, time and space, in the construction of the episodes and in the visual narration. Correspondence to: Fran?oise Decortis, Psychology and Education Sciences Department, University of Liege, 4000 Liege, Belgium. Email:francoise.decortis@ulg.ac.be     

Ubiquitous learning website: Scaffold learners by mobile devices with information-aware techniques

The portability and immediate communication properties of mobile devices influence the learning processes in interacting with peers, accessing resources and transferring data. For example, the short message and browsing functions in a cell phone provide users with timely and adaptive information access. Although many studies of mobile learning indicate the pedagogical potential of mobile devices, the screen size, computational power, battery capacity, input interfaces, and network bandwidth are too restricted to develop acceptable functionality for the entire learning processes in a handheld device. Therefore, mobile devices can be adopted to fill the gap between Web-based learning and ubiquitous mobile learning. This study first creates a website, providing functions enabling learning to take place anytime and anywhere with any available learning device, for ubiquitous learning according to various properties of mobile devices. Nowadays, learners’ behaviors on a website can be recorded as learning portfolios and analyzed for behavioral diagnosis or instructional planning. A student model is then built according to the analytical results of learning portfolios and a concept map of the learning domain. Based on the student model and learners’ available learning devices, three modules are developed to build a ubiquitous learning environment to enhance learning performance via learning status awareness, schedule reminders and mentor recommendation. Finally, an experiment is conducted with 54 college students after implementation of the ubiquitous learning website. Experimental results indicate that the proposed system can enhance three learning performance indicators, namely academic performance, task accomplishment rates, and learning goals achievement rates.     

Stop word location and identification for adaptive text recognition

Abstract. We propose a new adaptive strategy for text recognition that attempts to derive knowledge about the dominant font on a given page. The strategy uses a linguistic observation that over half of all words in a typical English passage are contained in a small set of less than 150 stop words. A small dictionary of such words is compiled from the Brown corpus. An arbitrary text page first goes through layout analysis that produces word segmentation. A fast procedure is then applied to locate the most likely candidates for those words, using only widths of the word images. The identity of each word is determined using a word shape classifier. Using the word images together with their identities, character prototypes can be extracted using a previously proposed method. We describe experiments using simulated and real images. In an experiment using 400 real page images, we show that on average, eight distinct characters can be learned from each page, and the method is successful on 90% of all the pages. These can serve as useful seeds to bootstrap font learning. Received October 8, 1999 / Revised March 29, 2000     

Responding to the Global Challenges: Regional Entrepreneurship within the Change Society

In this paper, some fundamental aspects of societal change processes are described, leading to proposals of how to cope with such changes through continuous learning within society. This change society is presently emerging worldwide. It is very much shaped by advanced networked information and communication technology. Correspondingly, certain trends are identified in this paper which indicate the change processes towards this new emerging society. Subsequently, different personal skills are described which are required for all members of society to cope with these trends. The paper finishes with a case study which deals with regional development through open networked business processes. The aim of the project described was to develop a joint family vacation concept in the former socialist East German state of Saxonia. Thus, it illustrates the change and learning processes across society which have taken place in many countries after the socialist era.     

User and Concept Studies as Tools in Developing Mobile Communication Services for the Elderly

The basis of this study was the ageing of the population all over the world. The study concentrated on finding out the key service needs of elderly people. The service needs from the end users’ as well as the experts’ perspective were gathered by means of various group methods such ideation sessions. Four mobile communication service concepts were created using these groups’ opinions. After diverse communication, these concepts were tested by the elderly. The research methods comprised a user study and a concept study.  Based on the results, the needs could be prioritised. Additionally, the main trend of the results confirmed the opinions presented in the literature. One important finding was the positive opinions about additional value of wireless devices and services. This knowledge can be used in mobile communication product development. Most of the elderly are ready to accept new forms of mobile communication service. Ease of use and actual need of the services are important criteria. The elderly are ready to begin using the services as long as they truly facilitate independent living.     

“We Release Them Little by Little”: Maturation and Gender Identity as Seen in the Use of Mobile Telephony

This paper examines the social meaning behind the adoption of mobile telephones by teenagers in Norway. Through this adoption process one can see the way in which youths are developing their adult identity as well as their gendered identity. The primary database used in this analysis is from two telephone questionnaires of Norwegian youth aged 13–20 carried out in October and December 1998. A total of 2007 interviews are included. The survey instrument covered teenagers’ ownership of mobile telephones, payment forms and the use of mobile telephones to send and receive Short Message System (SMS) text messages. In addition, the analysis draws on a survey of 1001 Norwegian parents and ethnographic interviews of 12 families.     

Overcoming the Lack of Screen Space on Mobile Computers

One difficulty for interface design on mobile computers is lack of screen space caused by their small size. This paper describes a small pilot study and two formal experiments that investigate the usability of sonically-enhanced buttons of different sizes. The underlying hypothesis being that presenting information about the buttons in sound would increase their usability and allow their size to be reduced. An experimental interface was created that ran on a 3Com Palm III mobile computer and used a simple calculator-style interface to enter data. The buttons of the calculator were changed in size between 4×4, 8×8 and 16×16 pixels and used a range of different types of sound from basic to complex. Results showed that sounds significantly improved usability for both standard and small button sizes – more data could be entered with sonically-enhanced buttons and subjective workload reduced. More sophisticated sounds that presented more information about the state of the buttons were shown to be more effective than the standard Palm III sounds. The results showed that if sound was added to buttons then they could be reduced in size from 16×16 to 8×8 pixels without much loss in quantitative performance. This reduction in size, however, caused a significant increase in subjective workload. Results also showed that when a mobile device was used in a more realistic situation (whilst walking outside) usability was significantly reduced (with increased workload and less data entered) than when used in a usability laboratory. These studies show that sound can be beneficial for usability and that care must be taken to do testing in realistic environments to get a good measure of mobile device usability.     

WIRE3: Driving Around the Information Super-Highway

Interactive voice browsers offer an alternative paradigm that affords ubiquitous mobile access to the WWW using a wide range of consumer devices. This technology can facilitate a safe, “hands-free” browsing environment that is of importance both to car drivers and various mobile and technical professionals. This paper describes the challenges of architecting an interactive voice browser that combines digital audio with the features of a speech synthesizer to make structural elements of the document explicit to the listener. The aesthetics of the audio rendition can simultaneously help reduce the monotony factor and enhance comprehension. The evolution of the voice browser gave rise to a new conceptual model of the HTML document structure and its mapping to a 3D audio space. A number of novel features are discussed for improving both the user’s comprehension of the HTML document structure and their orientation within it. These factors, in turn, can improve the effectiveness of the browsing experience.