APCO project 25 wireless data services over land mobile radio channel for smaller law enforcement agencies

Digital data messages are very important in modern communication systems and advanced mobile data technologies have opened the door to a wide range of applications and services in the public safety environment. Still, the availability of mobile data services among public safety agencies is hampered by two issues of the implementation of data communication: the reliability of commercial data services and the high cost of the equipment needed to support mixed voice and data transmissions over private land mobile radio channels. This thesis describes the design and development of an inexpensive Software Defined APCO Project 25 Data Base Station that allows smaller law enforcement agencies to enable data services in their cruisers in a cost effective way. The data base station is comprised of a standard PC interfaced to a commercial analog VHF FM transceiver via a commercial PC sound card. The base station is compliant with commercial P25 digital mobile radios and operates in parallel to commercial P25 digital voice communications equipment

"Fun place within a serious space”: stimulating community interaction and engagement through situated snapshots In a university setting

Networked public displays can stimulate interaction between members of place-based communities, e.g., through situated snapshots – photos taken through a display attached camera. Previous work pointed the need for deploying networked public display applications in various settings in order to make the findings transferable and generalizable and recommends that findings should be connected with research from community psychology. In this paper we report a 15-week “in the wild” deployment of the Moment Machine 2.0 that allowed taking situated snapshots at a university. The application’s evaluation involved in-depth interviews (n=20), survey (n=119), and log file analysis. We synthesize our findings with prior work and show how certain effects transfer across settings. We show how the application affected community interaction and sense of community as defined by McMillan and Chavis. We provide implications for design of similar experiences. Overall, our work contributes to the general knowledge of common effects produced by public displays

Developing a networked public display system

Engaging stakeholders in the design of networked public display systems is critical for long-term deployments. The authors describe the three-year development and installation of a display network at a university, revealing the fuzziness of stakeholder roles and need for compromise

Key challenges in application and content scheduling for Open Pervasive Display Networks

Today’s digital signage systems typically show content that has been scheduled well in advance by their respective “owners”, i.e., companies or individuals who paid for and/or operate the public display. However, with the shift to open display networks that can obtain content from many sources and the corresponding advances in interaction and sensing technologies, the scheduling requirements in this domain are set to change radically. For example, we envision that displays in our environment will soon be able to adapt to their surroundings and allow viewers to appropriate them by actively selecting and/or contributing content. Such levels of interactivity and context-awareness will require new approaches to content scheduling. In this paper we discuss the challenges faced in developing new forms of application and content scheduling for Open Pervasive Display Networks.(undefined

Audience monitor:an open source tool for tracking audience mobility in front of pervasive displays

Understanding an audience's behavior is an important aspect of evaluating display installations. In particular, it is important to understand how people move around in the vicinity of displays, including viewer transitions from noticing a display, through approach, to final use of the display. Despite the importance of measuring viewer mobility patterns, there are still relatively few low-cost tools that can be used with research display deployments to capture detailed spatial and temporal behavior of an audience. In this paper, we present an approach to audience monitoring that uses an off-the-shelf depth sensor and open source computer vision algorithms to monitor the space in front of a digital display, tracking presence and movements of both passers-by and display users. We believe that our approach can help display researchers evaluate their public display deployments and improve the level of quantitative data underpinning our field

Securely Storing and Sharing Memory Cues in Memory Augmentation Systems:A Practical Approach

A plethora of sensors embedded in wearable, mobile, and infrastructure devices allow us to seamlessly capture large parts of our daily activities and experiences. It is not hard to imagine that such data could be used to support human memory in the form of automatically generated memory cues, e.g., images, that help us remember past events. Such a vision of pervasive “memory-augmentation systems”, however, comes with significant privacy and security implications, chief among them the threat of memory manipulation: without strong guarantees about the provenance of captured data, attackers would be able to manipulate our memories by deliberately injecting, removing, or modifying captured data. This work introduces this novel threat of human memory manipulation in memory augmentation systems. We then present a practical approach that addresses key memory manipulation threats by securing the captured memory streams. Finally we report evaluation results on a prototypical secure camera platform that we built

Scheduling Content in Pervasive Display Systems

Digital displays are a ubiquitous feature of public spaces; London recently deployed a whole network of new displays in its Underground stations, and the screens on One Time Square (New York) allow for presentation of over $16,000$ square feet of digital media. However, despite decades of research into pervasive displays, the problem of scheduling content is under-served and there is little forward momentum in addressing the challenges brought with large-scale and open display networks. This paper presents the first comprehensive architectural model for scheduling in current and anticipated pervasive display systems. In contrast to prior work, our three-stage model separates out the process of high level goal setting from content filtering and selection. Our architecture is motivated by an extensive review of the literature and a detailed consideration of requirements. The architecture is realised with an implementation designed to serve the world's largest and longest-running research testbed of pervasive displays. A mixed-methods evaluation confirms the viability of the architecture from three angles: demonstrating capability to meet the articulated requirements, performance that comfortably fits within the demands of typical display deployments, and evidence of its ability to serve as the day-to-day scheduling platform for the previously described research testbed. Based on our evaluation and a reflection on paper as a whole, we identify ten implications that will shape future research and development in pervasive display scheduling

Design considerations for application selection and control in multi-user public displays

Urban spaces are increasingly embedded with various types of public digital displays. Many of these displays can be subject to multi-user interactions and support a broad range of applications. A fundamental implication emerging from the interactive nature of those applications is that users should have access to appropriate selection and control techniques that would allow them to drive the way applications are shown and used in the respective environment. Such techniques should enable each user to reason and express intentions about the system behavior, while also dealing with concurrent requests from multiple users in a way that is fair and clear. In this study, we aim to inform the definition of novel techniques for application selection and control in pervasive display environments that can address the above challenges. Drawing inspiration from traditional GUI interaction concepts we developed and deployed a public display system that supports multiple applications and is able to receive explicit content presentation requests from multiple viewers. Based on the experiment observations and interviews with the participants, we reached a set of design considerations for future pervasive displays environments that are open to third party applications providers and allow the audience to influence content presentation.info:eu-repo/semantics/publishedVersio

A longitudinal study of pervasive display personalisation

Widespread sensing devices enable a world in which physical spaces become personalised in the presence of mobile users. An important example of such personalisation is the use of pervasive displays to show content that matches the requirements of proximate viewers. Despite prior work on prototype systems that use mobile devices to personalise displays, no significant attempts to trial such systems have been carried out. In this paper we report on our experiences of designing, developing and operating the world’s first comprehensive display personalisation service for mobile users. Through a set of rigorous quantitative measures and eleven potential user/stakeholder interviews, we demonstrate the success of the platform in realising display personalisation, and offer a series of reflections to inform the design of future systems

Plantxel: Towards a plant-based controllable display

The use of plants as a mean for both visualization and interaction has been already explored in smart environments. In this work, we explore the possibility of constructing a controllable dynamic plant-based display using thigmonastic plants, i.e. plants that change the shape and position of their leaves as a response to external stimuli. As an initial step towards this vision, we first introduce our approach of building a plant-based pixel (plant-pixel, or plantxel), and the principles of composing a plantxel-based public display. We then present the results of a feasibility study conducted with Mimosa spegazzinii plants, showing that our approach can achieve an acceptable contrast ratio, which in turn depends on leaves density. Based on the results of the study, we present a working prototype of a plantxel that is composed of a plant, the air-based stimulation system, and the control logic. The prototype allowed us to assess the effectiveness of our design choices, and to outline some potential limitations. Finally, we discuss the possibilities of using such plant-based display for dynamic information visualization in public spaces and provide directions for future work