Mapping quality requirements for pervasive mobile games

Games have not received the full attention of the requirements engineering community. This scenario is becoming more critical as we move towards newer forms of games, such as pervasive games. Pervasiveness (the quality that distinguishes pervasive games from traditional digital games) holds several meanings, including being ubiquitous, permeating something, or spreading something, somewhere, in a physical space. Pervasiveness can be recognized in by the boundaries of the game expanding every time it is played, from the virtual (or fictional) world to the real world. Pervasive games are a new form of digital entertainment that has evolved in different forms, such as alternate reality games, transmedia games, and crossmedia games. Sensor technologies, networking capabilities, augmented reality systems, computer vision technology, the internet, and, especially, mobile devices have been responsible for the rapid evolution of this new form of digital product. This paper is focused on “pervasive mobile games”, which we define as context-aware games that use mobile devices. We bear in mind that mobile devices are currently the main driver for fulfilling the promises of pervasive game playing. Our investigations and experiments on this class of games led us to study the quality requirements for pervasive mobile games. Using different information sources, we gathered a set of interrelated characteristics that are crucial to the success of these games. In this paper, we begin to clarify the definition and scope of pervasive mobile games, which are controversial issues in the literature. Using these fundamentals, we propose a two-level conceptual map of non-functional requirements that helps to realize pervasiveness in pervasive mobile games. These non-functional requirements are then associated with a set of questions that help the designers in verifying tasks and operationalizing the requirements of a game. We also propose a dependence matrix for pervasive game qualities that enhances the insight into pervasiveness and reveals important guidelines for the game designers.     

A method to assess pervasive qualities in mobile games

Software designers are facing huge challenges imposed by a new generation of applications that mix real and digital worlds, such as pervasive games. This type of game has recently become a worldwide phenomenon, with thousands of people walking in the streets with smartphones to interact with the physical environment. In this paper, we propose a new method to assess pervasive qualities in pervasive mobile games, which can be customized and extended to other ubiquitous applications. This method generates a quality report, which consists of a quality spreadsheet (containing metric values and comments) and a quality vector (representing the game quality profile in the form of a bar chart). In addition, we can compare quality vectors using similarity criteria. In this paper, we apply the proposed method to commercial and academic prototype games to shed more light on their pervasive characteristics and identify ways to improve the overall quality that sets these games apart from traditional digital games—that is, pervasiveness.     

一种提高室内定位精度的算法

室内定位技术对于室内物品的实时监管具有重要的实际应用价值。为了进行室内物品的精确定位,文中建立了一种基于距离的最优估计定位模型,并引入变尺度(DFP)算法对模型进行求解,从而达到提高坐标精度的目的。本设计首先对原始距离信息利用最小二乘估计、三次样条插值法来提高测距精度;其次通过三圆公共弦交点法确定出初始坐标值;然后把空间几何关系转换为无约束极小值问题,再采用DFP法对初始坐标进一步精化,以得出更为精确的坐标值。最后通过两种模拟实验对算法进行验证,结果表明:引入最优估计理论的室内定位算法,具有更高的定位精度。     

SPECs: personal pervasive systems

We have devised a system of wireless SPECs-small personal everyday computers-that can be worn or attached to a place or thing and, unlike Active Badges, can be networked without a centralized computer. Our approach increases availability on a per-user basis, rather than for an entire community, to create a truly personal pervasive system. Users themselves deploy and maintain these autonomous devices throughout their own normal living areas: at the office, in their car, at home, and even in public spaces.     

Locating experience: touring a pervasive performance

Touring location-based experiences is challenging, as both content and underlying location services must be adapted to each new setting. A study of a touring performance called Rider Spoke as it visited three different cities reveals how professional artists developed a novel approach to these challenges in which users drove the co-evolution of content and the underlying location service as they explored each new city. We show how the artists iteratively developed filtering, survey, visualization, and simulation tools and processes to enable them to tune the experience to the local characteristics of each city. Our study reveals how by paying attention to both content and infrastructure issues in tandem, the artists were able to create a powerful user experience that has since toured to many different cities.     

Middleware for pervasive computing: A survey

The rapidly emerging area of pervasive computing faces many challenging research issues critical to application developers. Wide heterogeneity of hardware, software, and network resources pose veritable coordination problems and demand thorough knowledge of individual elements and technologies. In order to ease this problem and to aid application developers, different middleware platforms have been proposed by researchers. Though the existing middleware solutions are useful, they themselves have varied features and contribute partially, for context, data, or service management related application developments. There is no single middleware solution that can address a majority of pervasive computing application development issues, due to the diverse underlying challenges. In this survey paper, we identify different design dimensions of pervasive computing middleware and investigate their use in providing various system services. In-depth analysis of the system services have been carried out and middleware systems have been carefully studied. With a view to aid future middleware developers, we also identify some challenging open research issues that have received little or no attention in existing middleware solutions.     

Project Aura: toward distraction-free pervasive computing

The most precious resource in a computer system is no longer its processor, memory, disk, or network, but rather human attention. Aura aims to minimize distractions on a user's attention, creating an environment that adapts to the user's context and needs. Aura is specifically intended for pervasive computing environments involving wireless communication, wearable or handheld computers, and smart spaces. Human attention is an especially scarce resource in such environments, because the user is often preoccupied with walking, driving, or other real-world interactions. In addition, mobile computing poses difficult challenges such as intermittent and variable-bandwidth connectivity, concern for battery life, and the client resource constraints that weight and size considerations impose. To accomplish its ambitious goals, research in Aura spans every system level: from the hardware, through the operating system, to applications and end users. Underlying this diversity of concerns, Aura applies two broad concepts. First, it uses proactivity, which is a system layer's ability to anticipate requests from a higher layer. In today's systems, each layer merely reacts to the layer above it. Second, Aura is self-tuning: layers adapt by observing the demands made on them and adjusting their performance and resource usage characteristics accordingly. Currently, system-layer behavior is relatively static. Both of these techniques will help lower demand for human attention.     

Video sketches: exploring pervasive computing interaction designs

Some industry designers have used video scenarios - short movies that show how users might actually interact with a product. However, cost and production issues undermine this method's usefulness. To address this challenge, the author and his students have developed a new method called video sketches. Although similar to video scenarios, video sketches significantly lower the production threshold by replacing video footage with photos. Unlike traditional video, video sketches require tools that most design students have on hand. Students used consumer-level digital still cameras and laptops as their main tools. They composited the images using standard graphic design software and constructed the linear story using low-end video-editing software. Audio production presented the most difficult challenge. Students produced their video sketches following the traditional three-phase (preproduction, production, and postproduction) process. Traditional cinematography issues also apply to making video sketches.     

PvcwCORBA:普适计算环境中间件的实现

针对普适环境的平台的多样性、资源的有限性、设备的移动性和应用高性能要求等需求,提出了其中间件的设计和实现方法,并据此构建了pvcwCORBA。通过试验验证了pvcwCORBA作为支持无线接入功能的高性能、嵌入式CORBA,能够适应普适计算环境的要求。     

Application mobility in pervasive computing: A survey

Pervasive computing applications often need to maintain uninterrupted computing experiences when users move across devices. This advanced feature, recognized as application mobility, brings many challenges to the pervasive computing community. For a better understanding of the challenges and existing approaches to application mobility, this paper surveys related work with a classification and comparison framework established along four dimensions of design concerns in application migration: temporal, spatial, entity and other concerns. Through this survey this paper attempts to provide a systematic reference for developers to leverage off among different migration strategies for seamless application mobility. Moreover, it sheds some light on future work directions.     

PICO: a middleware framework for pervasive computing

The pervasive information community organization is a framework for creating mission-oriented dynamic communities of autonomous software entities that perform tasks for users and devices. PICO's telemedicine example scenario demonstrates its potential as a simple, unique, and versatile middleware framework for pervasive computing.     

MyAds: A system for adaptive pervasive advertisements

In this paper we show how pervasive technologies can be employed on a public-display advertisement scenario to enable behavioral self-adaptation of content. We show this through MyAds, a system capable of exploiting pervasive technologies to autonomously adapt the advertisement process to the trends of interests detected among the audience in a venue. After describing the rationale, the architecture and the prototype of MyAds, we describe the advantages brought by the use of such a system, in terms of impact on the audience and economic efficiency. The comparison of MyAds performances with different advertisement selection techniques confirms the validity of our advertisement model, and our prototype in particular, as a means for maximising product awareness in an audience and for enhancing economic efficiency.     

rfid in pervasive computing: State-of-the-art and outlook

rfid has already found its way into a variety of large scale applications and arguably it is already one of the most successful technologies in the history of computing. Beyond doubt, rfid is an effective automatic identification technology for a variety of objects including natural, manufactured and handmade artifacts; humans and other species; locations; and increasingly media content and mobile services. In this survey we consider developments towards establishing rfid as the cost-effective technical solution for the development of open, shared, universal pervasive computing infrastructures and look ahead to its future. In particular, we discuss the ingredients of current large scale applications; the role of network services to provide complete systems; privacy and security implications; and how rfid is helping prototype emerging pervasive computing applications. We conclude by identifying common trends in the new applications of rfid and ask questions related to sustainable universal deployment of this technology.     

Buyer-supplier games: Optimization over the core

In a buyer-supplier game, a special type of assignment game, a distinguished player, called the buyer, wishes to purchase some combinatorial structure. A set of players, called suppliers, offer various components of the structure for sale. Any combinatorial minimization problem can be transformed into a buyer-supplier game. While most previous work has been concerned with characterizing the core of buyer-supplier games, in this paper we study optimization over the set of core vectors. We give a polynomial time algorithm for optimizing over the core of any buyer-supplier game for which the underlying minimization problem is solvable in polynomial time. In addition, we show that it is hard to determine whether a given vector belongs to the core if the base minimization problem is not solvable in polynomial time. Finally, we introduce and study the concept of focus point price, which answers the question: If we are constrained to play in equilibrium, how much can we lose by playing the wrong equilibrium?     

Connecting the physical world with pervasive networks

This article addresses the challenges and opportunities of instrumenting the physical world with pervasive networks of sensor-rich, embedded computation. The authors present a taxonomy of emerging systems and outline the enabling technological developments.     

Understanding and measuring the urban pervasive infrastructure

The increasing popularity of mobile computing devices has allowed for new research and application areas. Specifically, urban areas exhibit an elevated concentration of such devices enabling potential ad-hoc co-operation and sharing of resources among citizens. Here, we argue that people, architecture and technology together provide the infrastructure for these applications and an understanding of this infrastructure is important for effective design and development. We focus on describing the metrics for describing this infrastructure and elaborate on a set of observation, analysis and simulation methods for capturing, deriving and utilising those metrics.

Jini home networking: a step toward pervasive computing

Jini connection technology forms a network of devices on the fly, without manual connection or configuration. It can also complement other technologies that strive for "anytime, anywhere" connectivity. The article looks at lookup and discovery services; reliability and scalability; Jini architectural requirements; service for non-Jini devices; Jini mobile edition for wireless devices; Jini implementations; and competing and related technologies.     

Situation identification techniques in pervasive computing: A review

Pervasive systems must offer an open, extensible, and evolving portfolio of services which integrate sensor data from a diverse range of sources. The core challenge is to provide appropriate and consistent adaptive behaviours for these services in the face of huge volumes of sensor data exhibiting varying degrees of precision, accuracy and dynamism. Situation identification is an enabling technology that resolves noisy sensor data and abstracts it into higher-level concepts that are interesting to applications. We provide a comprehensive analysis of the nature and characteristics of situations, discuss the complexities of situation identification, and review the techniques that are most popularly used in modelling and inferring situations from sensor data. We compare and contrast these techniques, and conclude by identifying some of the open research opportunities in the area.     

Privacy in pervasive environments: next generation labeling protocols

In pervasive environments, privacy is likely to be a major issue for users, and users will want to be notified of potential data capture. To provide notice to users, this paper argues for what it calls labeling protocols, technical mechanisms through which users can be informed of data requests and their consequences. Recent experiences with the Platform for Privacy Preferences Project (P3P), an attempt to provide privacy mechanisms for the Web, suggest important lessons for the design of a next generation labeling protocol that will be usable and useful in pervasive environments. This paper examines the P3P lessons and open issues with an eye to pervasive requirements.