The design of a handheld,location-aware guide for indoor environments

Because of the growing spread of mobile and small devices (like PDAs, mobile phones, etc.), designers and developers of interactive systems have to consider user mobility and the dynamic context of use. In this paper we discuss the design criteria we have defined for developing handheld location-aware systems for indoor environments. We analyse some of the technologies currently available for this purpose and examine how to use them in order to obtain location-dependent information. We report on our experience in designing a location-aware guide for museum visitors and identify possible design criteria for this type of system, which uses automatic detection of a change in environment to trigger the presentation of multi-modal, context-dependent information through a hand-held guide.     

Designing an extensible architecture for Personalized Ambient Information

Ambient displays provide us with information in the background of our awareness. However, as each user has individual wishes and needs of how, which and when information is presented, the acceptance of ambient displays is low.In this paper we introduce an extensible architecture for personalized ambient information.We employ a notification system to extend the capability of a fixture to display more than one variable. Multiple variables can be updated by multiple information providers. Thereby, our architecture covers a broader spectrum of notifications from alarms to ambient information.We evaluate our concept within a dual-task experiment in comparison to preset notifications. The results show a level of self-interruption which is significantly lower than using preset notifications. Therefore our approach outperforms preset notifications and moves ambient displays closer to secondary displays in human–computer interaction.     

Examining proactiveness and choice in a location-aware mobile museum guide

Cultural heritage is an area that has recently drawn research attention, especially for exploring ways to harness novel mobile technologies for supporting visitors. The main benefit of these novel technologies is their ability to provide personalized, context-aware information services to their users. However, the use of context-awareness is connected to a fundamental issue of proactiveness - should the system keep the user in control all the time and only respond to user requests, or should the system take initiative and propose its services when needed? Proactiveness of mobile visitors’ guides brings with it a possibility for better service to the user at the cost of taking control out of the user’s hand. The amount of choice given to visitors is another key issue. With the vast amount of information available for each exhibit, adaptation of the amount of information by limiting the number of content items, could be warranted to filter the information according to the visitors needs. However, it is not clear how reducing choice in terms of the number of content items that are presented to the visitor affects visitor behavior and satisfaction. We examined these issues in a controlled user study conducted with actual museum visitors; comparing usage, behavior patterns, and attitudes of visitors using three versions of a location-aware mobile museum guide.     

Mobile guides: Taxonomy of architectures,context awareness,technologies and applications

Portable devices are increasingly employed in a wide range of mobile guidance applications. Typical examples are guides in urban areas, museum guides, and exhibition space aids. The demand is for the delivery of context-specific services, wherein the context is typically identified by a combination of data related to location, time, user profile, device profile, network conditions and usage scenario. A context-aware mobile guide is intended to provide guidance services adjusted to the context of the received request. The adjustment may refer to tailoring the user interface to the perceived context, as well as delivering the right type of information to the right person at the right time and the right location. It may also refer to intermediary adaptation, as in the case of mobile multimedia transmission. This paper offers a taxonomy of mobile guides considering multiple criteria. The taxonomy considers several aspects of the mobile applications space, including context awareness, client architectures, mobile user interfaces, as well as offered functionalities, highlighting functional, architectural, technological, and implementation issues. Existing implementations are classified accordingly and a discussion of research issues and emerging trends is offered.     

Ontology-Based User Modeling in an Augmented Audio Reality System for Museums

Ubiquitous computing is a challenging area that allows us to further our understanding and techniques of context-aware and adaptive systems. Among the challenges is the general problem of capturing the larger context in interaction from the perspective of user modeling and human–computer interaction (HCI). The imperative to address this issue is great considering the emergence of ubiquitous and mobile computing environments. This paper provides an account of our addressing the specific problem of supporting functionality as well as the experience design issues related to museum visits through user modeling in combination with an audio augmented reality and tangible user interface system. This paper details our deployment and evaluation of ec(h)o – an augmented audio reality system for museums. We explore the possibility of supporting a context-aware adaptive system by linking environment, interaction objects and users at an abstract semantic level instead of at the content level. From the user modeling perspective ec(h)o is a knowledge-based recommender system. In this paper we present our findings from user testing and how our approach works well with an audio and tangible user interface within a ubiquitous computing system. We conclude by showing where further research is needed.     

Designing wearable vibrotactile notifications for information communication

Visual and auditory stimuli are frequently used for information communication on mobile devices. These feedback modalities, however, are less suitable for emerging wearable devices that are intended to support multitasking with minimum interruption. Use of vibrotactile stimuli is great alternatives due to their low disruption and high ability to attract attention.Currently, effective vibration notifications are still elusive. In the present study, we explored a vibration notification mechanism by using a singular vibration motor to generate various vibration stimuli. This solution is appropriate for existing wearable devices that have a small form factor, limited internal space, and low battery capacity. Our first experiment investigated individuals’ vibration perception in order to select a set of vibration stimuli that were detectable and discriminable. In our second experiment, we mapped the 5 vibration stimuli that were identified in the first experiment to various mobile application events and evaluated user performance using a wrist mounted prototype device. Results indicate that our vibration notification design achieved an average response accuracy rate of 82.3% (SD=18.0%) and an average response time of 2.83 (SD=0.83) s. Moreover, results of the post-test questionnaire revealed that the average perceived usefulness towards the vibration notification design was rated 5.5 (SD=1.18) and the average perceived ease of use was rated 5.0 (SD=1.36) when using a 7-point rating scale. Overall, results indicated the present vibration notification design was perceived as useful and highlighted opportunities for improving perceptions of ease of use. Our findings inform the design of future vibration notifications on wearable devices and highlight the importance of increasing pair-wise dissimilarities, perceived usefulness, and perceived ease of use in designing effective vibration notifications.     

Context-dependent awareness support in open collaboration environments

The widespread adoption of online services for performing work, home and leisure tasks enables users to operate in the ubiquitous environment provided by the Internet by managing a possibly high number of parallel (private and shared) activity contexts. The provision of awareness information is a key factor for keeping users up-to-date with what happens around them; e.g., with the operations performed by their collaborators. However, the delivery of notifications describing the occurred events can interrupt the users’ activities, with a possible disruptive effect on their emotional and attentional states. As a possible solution to the trade-off between informing and interrupting users, we defined two context-dependent notification management policies which support the selection of the notifications to be delivered on the basis of the user’s current activities, at different granularity levels: general collaboration context versus task carried out. These policies are offered by the COntext depeNdent awaReness informAtion Delivery (CONRAD) framework. We tested such policies with users by applying them in a collaboration environment that includes a set of largely used Web 2.0 services. The experiments show that our policies reduce the levels of workload on users while supporting an up-to-the-moment understanding of the interaction with their shared contexts. The present paper presents the CONRAD framework and the techniques underlying the proposed notification policies.     

云环境下实时消息推送服务构建研究

随着移动互联网技术的发展,各类消息纵横交错,人们在获取关联信息时常感到无从选择。传统的消息获取,用户需要主动拉取网络存储的消息,此种方式获取消息的效率极其低下,会产生众多与用户无关的消息。消息推送需要用户不停地拉取刷新,属于被动推送。随着云技术的发展,消息推送技术逐步转变为云推送,告别了单一服务器推送的模式。对现有各类消息推送技术进行研究和分析,针对传统基于主题订阅模式的消息推送服务只能对应单一移动端通信的不足,提出了云实验环境下实现实时消息推送服务的构建方案,设计了消息推送服务(PushWeb)的运行框架,运用H5技术中的WebSocket技术实现了管理平台和移动客户端应用程序,并将其部署在阿里云中,经测试在良好的网络环境下能够将消息实时准确地推送至移动端。     

Modelling Shared Contexts in Cooperative Environments: Concept, Implementation, and Evaluation

Users who work together require adequate information about their cooperative environment: about other group members presence and activities, about shared artefacts, etc. In the CSCW literature several concepts, prototypes, and systems for providing this group awareness information have been presented. In general, they capture information from the environment, process it, and present it to the users. This paper addresses the processing aspect; in particular, we present a concept for processing awareness information by means of awareness contexts. With this concept we address the problem of contextualising event notifications enabling the presentation of notifications in the appropriate user situation. We describe a lightweight model and its integration into an event and notification infrastructure. We report on an empirical study, and draw some conclusions for the design of context-awareness for cooperative environments.     

Modelling Shared Contexts in Cooperative Environments: Concept,Implementation, and Evaluation

Users who work together require adequate information about their cooperative environment: about other group members presence and activities, about shared artefacts, etc. In the CSCW literature several concepts, prototypes, and systems for providing this group awareness information have been presented. In general, they capture information from the environment, process it, and present it to the users. This paper addresses the processing aspect; in particular, we present a concept for processing awareness information by means of awareness contexts. With this concept we address the problem of contextualising event notifications enabling the presentation of notifications in the appropriate user situation. We describe a lightweight model and its integration into an event and notification infrastructure. We report on an empirical study, and draw some conclusions for the design of context-awareness for cooperative environments.     

Effects of the design of mobile security notifications and mobile app usability on users’ security perceptions and continued use intention

The explosive global adoption of mobile applications (i.e., apps) has been fraught with security and privacy issues. App users typically have a poor understanding of information security; worse, they routinely ignore security notifications designed to increase security on apps. By considering both mobile app interface usability and mobile security notification (MSN) design, we investigate how security perceptions of apps are formed and how these perceptions influence users’ intentions to continue using apps. Accordingly, we designed and conducted a set of controlled survey experiments with 317 participants in different MSN interface scenarios by manipulating the types of MSN interfaces (i.e., high vs. low disruption), the context (hedonic vs. utilitarian scenarios), and the degree of MSN intrusiveness (high vs. low intrusiveness). We found that both app interface usability and the design of MSNs significantly impacted users’ perceived security, which, in turn, has a positive influence on users’ intention to continue using the app. In addition, we identified an important conundrum: disruptive MSNs—a common approach to delivering MSNs—irritate users and negatively influence their perceptions of app security. Thus, our results directly challenge current practice. If these results hold, current practice should shift away from MSNs that interrupt task performance.     

Look, Ma, My homepage is Mobile!

Much of the ongoing research in ubiquitous computing has concentrated on providing context information, e.g. location information, to the level of services and applications. Typically, mobile clients obtain location information from their environment which is used to provide “locally optimal” services. In contrast, it may be of interest to obtain information about the current context a mobile user or device is in, from a client somewhere on the Web, i.e. to use the mobile device as an information provider for Internet clients. As an instance of such services we propose the metaphor of a “location-aware” Web homepage of mobile users providing information about, e.g. the current location a mobile user is at. Requesting this homepage can be as easy as typing a URL containing the mobile user's phone number such ashttp://mhp.net/+49123456789 in an off-the-shelf browser. The homepage is dynamically constructed as Web users access it and it can be configured in various ways that are controlled by the mobile user. We present the architecture and implementation and discuss issues around this example of “inverse” ubiquitous computing.     

Role of transfer-based and performance-based cues on initial trust in mobile shopping services: a cross-environment perspective

Building initial trust with consumers is critical for e-retailers. Drawing on the elaboration likelihood model, this study examines the factors affecting initial trust in mobile shopping services by focusing on transfer-based and performance-based trust building mechanisms in a web-mobile services extension context. A developed research model reflecting the above two mechanisms is empirically tested on data collected from 192 undergraduate students who were web-shopping users of a famous business-to-consumer retailer in China. The results indicate that transfer-based cues including trust in web shopping services and functional consistency, in combination with performance-based cues including mobile information quality and mobile service quality, significantly affect initial trust in mobile shopping services. In addition, mobile information quality had a stronger, while mobile service quality had a weaker impact on initial trust in mobile shopping services when the consumer had a low level of self-efficacy for change. However, the moderation effects of user involvement were not significant.     

一个基于移动视觉搜索技术的博物馆导览系统

为了对游客的参观过程提供个性化导览服务,使游客可以通过手机拍照的方式获取展品的相关资讯.提出一个基于移动视觉搜索技术的博物馆导览系统.针对手机性能的差异性,提出一种改进的移动视觉搜索系统的框架,使得系统既能在服务器端对海量展品进行识别,又能在手机端对特定区域内展品实时识别;并基于这一框架实现了一个原型系统.与现有的导览系统相比,文中系统的交互方式更加人性化,提供的展品信息更丰富、全面,且无需在馆内安装任何辅助设备,能够更广泛地适用于博物馆导览.实验结果证明了该系统的可行性和实用性.     

Adaptive interaction support in ambient-aware environments based on quality of context information

Ambient-aware environments are technologically augmented with myriad sensors, devices and other emerging services in order to support users. However, users find it complex in interacting with such environments due to the presence of numerous devices and services. In this situation, providing context-aware implicit or automatic interaction support may help reducing the cognitive load of the users and facilitate easy access of the available devices and services. However, due to the imprecision in context information, implicit interactions performed by the environment often leads to mis-automation. The result of such impaired implicitness causes distrust and dissatisfaction to the user. In order to address this issue, we propose a system that considers quality of information to dynamically adjust the level of implicit interaction and allows a system to operate in different modes such as full-automation, action suggestion, simple notification, or null action. We conduct experiment in a smart home scenario in order to elicit users’ acceptance and trust regarding the proposed system. Our experiment shows that dynamic and alternative mode of interaction not only increases the satisfaction of users but also helps to avoid distrust in automated actions carried out by the environment under varying contexts.     

A web-based pervasive recommendation system for mobile tourist guides

Mobile tourist guides have attracted considerable research interest during the past decade, resulting in numerous standalone and web-based mobile applications. Particular emphasis has been given to personalization of services, typically based on travel recommender systems used to assist tourists in choosing places to visit; these systems address an important aspect of personalization and hence reduce the information burden for the user. However, existing systems fail to exploit information, behaviours, evaluations or ratings of other tourists with similar interests, which would potentially provide ground for the cooperative production of improved tourist content and travel recommendations. In this paper, we extend this notion of travel recommender systems utilizing collaborative filtering techniques while also taking into account contextual information (such as the current user’s location, time, weather conditions and places already visited by the user) for deriving improved recommendations in pervasive environments. We also propose the use of wireless sensor network (WSN) installations around tourist sites for enabling precise localization and also providing mobile users convenient and inexpensive means for uploading tourist information and ratings about points of interest (POI) via their mobile devices. We also introduce the concept of ‘context-aware rating’, whereby user ratings uploaded through WSN infrastructures are weighted higher to differentiate among users that rate POIs using the mobile tourist guide application while onsite and others using the Internet away from the POI.     

Personalization for unobtrusive service interaction

Increasingly, mobile devices play a key role in the communication between users and the services embedded in their environment. With ever greater number of services added to our surroundings, there is a need to personalize services according to the user needs and environmental context avoiding service behavior from becoming overwhelming. In order to prevent this information overload, we present a method for the development of mobile services that can be personalized in terms of obtrusiveness (the degree in which each service intrudes the user’s mind) according to the user needs and preferences. That is, services can be developed to provide their functionality at different obtrusiveness levels depending on the user by minimizing the duplication of efforts. On the one hand, we provide mechanisms for describing the obtrusiveness degree required for a service. On the other hand, we make use of Feature Modeling techniques in order to define the obtrusiveness level adaptation in a declarative manner. An experiment was conducted in order to put in practice the proposal and evaluate the user acceptance for the personalization capabilities provided by our approach.