Supporting rapid design and evaluation of pervasive applications: challenges and solutions

Along with the improvement of the key technologies for pervasive computing, the design of applications itself has emerged as a notable research area. A design should decide which features go into the application of supporting its context-awareness and ascertaining how well those features add value for users with an acceptable user experience. This paper initially identifies the challenges in designing and evaluating pervasive applications. It then presents a condensed survey of prototyping techniques and existing toolkits with the aim of understanding how the design issues have been addressed by research prototypes. At the end, we describe various open issues with suggestions of possible ways to extend the capabilities of current prototyping toolkits.     

Multipurpose prototypes for assessing user interfaces in pervasive computing systems

In pervasive computing systems, prototypes serve several uses and have different requirements related to those uses. We've developed CogTool to enable low-cost, rapid construction of interactive prototypes that serve all three UI purposes. CogTools core prototyping technique is storyboarding -specifically, interactive storyboarding using HTML. Rather than covering all possible pervasive systems, CogTool focuses on systems involving deliberate commands that the user invokes by some motor action. Such systems include PDAs, cell phones, handheld terminals (such as those used by rental car return personnel), in-vehicle driver information systems, and certain wearable computers that run desktop- or PDA-like applications.     

A survey of applications systems prototyping in industry

Managers of information systems development are faced with a substantial backlog of development projects. Traditional approaches to developing systems can not keep pace with new application demand. New methods must be found to develop systems. This study investigates prototyping, an approach that promises order-of-magnitude reductions in the time and effort required to implement satisfactory information systems.A mail survey was used to collect information about systems development and prototyping in Fortune 500 firms. Data was collected on methodologies, tools, and practices from the Directors of Information Systems. The findings suggest that a large number of organizations are prototyping and consider it successful. Generic high level prototyping tools are rated and the reasons for replacing prototypes with conventionally developed systems are explored.     

Virtual Video Prototyping

Computing power is an integrated part of our physical environment, and since our physical environment is three-dimensional, the virtual studio technology, with its unique potential for visualizing digital 3D objects and environments along with physical objects, offers an obvious path to pursue in order to envision future usage scenarios in the domain of pervasive computing.We label the work method virtual video prototyping, which grew out of a number of information systems design techniques along with approaches to visualization in the field of architecture and set design.We present a collection of virtual video prototyping cases and use them as the platform for a discussion, which pinpoint advantages and disadvantages of working with virtual video prototyping as a tool for communication, experimentation and reflection in the design process. Based on more than ten cases we have made the observations that virtual video prototypes 1) are a powerful medium of communication in development teams and for communication with industry partners and potential investors, 2) support both testing and generating ideas 3) are particular suited for addressing spatial issues and new ways of interacting. In addition practical use of virtual video prototypes has indicated the need to take into account some critical issues including a) production resources, b) hand-on experience, and c) the seductive power of virtual video prototypes.     

Prototyping in theory and in practice: A study of the similarities and differences between engineers and designers

Prototyping can be seen as the heart of the innovation process. Typically, engineers and designers both work on prototyping activities, but their diverse backgrounds make for different perspectives on prototyping. Based on earlier literature, this study investigates commonalities and differences in the prototyping behavior of engineers and designers. For this study, semi‐structured interviews and workshops with different experiments were conducted. Using low‐fidelity prototypes, our results indicated that there are differences in the early phase of prototyping. Engineers focused on the features and functions of a prototype and needed to meet specific goals in order to push the process forward. Designers, on the other hand, used prototypes to investigate the design space for new possibilities, and were more open to a variety of prototyping materials and tools, especially for low‐fidelity prototypes. In the later prototyping phases, the prototyping behaviors of engineers and designers became similar. Our study contributes to the understanding of prototyping purposes, activities, and processes across disciplines, and supports the management of prototyping in new product development processes.     

Rapid Prototyping for Pervasive Applications

VisualRDK is a high-level programming language for prototyping pervasive applications. Context is tightly integrated into the language itself, so developers can attach functionality to locations, persons, or situations instead of the device. Pervasive computing appliances range from consumer devices over embedded sensor boards to PCs and large-scale context servers. Because these devices vary tremendously in their capabilities, application developers must create different programming models for every class of device. This makes rapid prototyping infeasible as soon as more than one class of devices is involved. Rapid prototyping therefore requires a programming model that hides the environment's heterogeneity.     

A Solution of Data Inconsistencies in Data Integration ——- Designed for Pervasive Computing Environment

New challenges including how to share information on heterogeneous devices appear in data-intensive pervasive computing environments. Data integration is a practical approach to these applications. Dealing with inconsistencies is one of the important problems in data integration. In this paper we motivate the problem of data inconsistency solution for data integration in pervasive environments. We define data quality criteria and expense quality criteria for data sources to solve data inconsistency. In our ...     

Virtual prototyping of automated manufacturing systems with Geometry-driven Petri nets

The design process of automated manufacturing systems typically involves physical prototypes to validate the interactions between hardware and software components. However, physical prototyping is expensive and time consuming, which often leads to insufficient opportunities for testing early during the development cycle. Our objective is to improve this situation by providing a method to develop realistic prototypes using virtual reality technology that can be applied during earlier development stages. Our approach combines a virtual reality engine capable of enacting the laws of rigid body physics with a new hybrid software modelling language to control the simulated hardware using virtual sensors and actuators as they would be present in a physical prototype. The new modelling language is called Geometry-driven Petri nets (GPN) and combines a class of timed, high-level Petri nets with data structures used in state-of-the-art VR environments. This article describes the new GPN approach, applies it to a case study of an automated manufacturing line, and compares it with related approaches.     

A virtual prototyping system for rapid product development

This paper describes a virtual prototyping (VP) system that integrates virtual reality with rapid prototyping (RP) to create virtual or digital prototypes to facilitate product development. The proposed VP system incorporates two new simulation methodologies, namely the dexel-based and the layer-based fabrication approaches, to simulate the powder-based and the laminated sheet-based RP processes, respectively. The dexel-based approach deposits arrays of solid strips to form a layer, while the layer-based approach directly forms a complete layer by extruding the slice contours. The layer is subsequently stacked up to fabricate a virtual prototype. The simulation approaches resemble the physical fabrication processes of most RP systems, and are therefore capable of accurately representing the geometrical characteristics of prototypes. In addition to numerical quantification of the simulation results, the system also provides stereoscopic visualisation of the product design and its prototype for detailed analyses. Indeed, the original product design may be superimposed on its virtual prototype, so that areas with dimensional errors beyond design limits may be clearly highlighted to facilitate point-to-point analysis of the surface texture and the dimensional accuracy of the prototype. Hence, the key control parameters of an RP process, such as part orientation, layer thickness and hatch space, may be effectively tuned up for optimal fabrication of physical prototypes in subsequent product development. Furthermore, the virtual prototypes can be transmitted via the Internet to customers to facilitate global manufacturing. As a result, both the lead-time and the product development costs can be significantly reduced.     

面向领域的简化的快速需求分析方法

简化的面向领域的快速原型法，面向特定领域，根据数据库应用的特点，将需求分析分为两个阶段，采用建立某个特殊领域的需求分析的参考原型集的方法，简化了作为需求分析工具的系统原型的建设，这些面向特定领域的参考原型能够协助设计人员在需求分析阶段更好地完成需求采集工作，同时它们又是可进化的原型，经过反复修改使用，其表达能力将不断增强，将有效地节省同类系统开发的时间和费用，降低系统开发的风险。在这些简易、快速的原型基础上进行需求分析，大大地提高了需求分析的效率和准确性。     

SCRAM–CK: applying a collaborative requirements engineering process for designing a web based e-science toolkit

This paper presents SCRAM–CK, a method to elicit requirements by means of strong user involvement supported by prototyping activities. The method integrates two existing approaches, SCRAM and CK theory. SCRAM provides the framework for requirements management, while CK theory provides a framework for reasoning about design and its evolution. The method is demonstrated with the definition and refining of requirements for the BioVeL web toolkit. The objective of BioVeL is to allow scientists to understand, run, modify and construct workflows for data analysis with minimal training using a web-based interface. The proposed method is supported by prototyping activities for gathering user feedback, and refining requirements and design proposals. Using this method, the prototypes evolved from simple workflow execution enablers to include more complex functionalities for reviewing, modifying and building workflows in later versions. This paper presents a contribution to the application of techniques for requirements engineering. SCRAM–CK is an amalgamated method that combines a user-centred continuous refinement approach with support for design evolution through prototyping. The paper also shows the influence of the requirements engineering process in the evolution of design proposals.     

Contrasting usability evaluation methods with blind users

Usability tests are a part of user-centered design. Usability testing with disabled people is necessary, if they are among the potential users. Several researchers have already investigated usability methods with sighted people. However, research with blind users is insufficient, for example, due to different knowledge on the use of assistive technologies and the ability to analyze usability issues from inspection of non-visual output of assistive devices. From here, the authors aspire to extend theory and practice by investigating four usability methods involving the blind, visually impaired and sighted people. These usability methods comprise of local test, synchronous remote test, tactile paper prototyping and computer-based prototyping. In terms of effectiveness of evaluation and the experience of participants and the facilitator, local tests were compared with synchronous remote tests and tactile paper prototyping with computer-based prototyping. Through the comparison of local and synchronous remote tests, it has been found that the number of usability problems uncovered in different categories with both approaches was comparable. In terms of task completion time, there is a significant difference for blind participants, but not for the visually impaired and sighted. Most of the blind and visually impaired participants prefer the local test. As for the comparison of tactile paper prototyping and computer-based prototyping, it has been revealed that tactile paper prototyping provides a better overview of an application while the interaction with computer-based prototypes is closer to reality. Problems regarding the planning and conducting of these methods as they arise in particular with blind people were also discussed. Based on the authors’ experiences, recommendations were provided for dealing with these problems from both the technical and the organization perspectives.     

Unpacking the notion of prototype archetypes in the early phase of an innovation process

The literature on new product development examines a variety of roles that prototypes can play based on the phase of the design process when they are used, but the characteristics of these prototypes that correspond to the expected outcomes, especially in the early phase of the design process, are understudied. We address this gap by studying the characteristics of the prototypes used in the design process (especially during the early phase) that correspond to their roles. Based on an analysis of six cases of prototypes that are used early on in the design process, we characterize three different archetypes of artefacts: stimulators, demonstrators, and validators, and we emphasize the coherence between the role they play in the design process and the characteristics that enable these roles. Specifying the roles of these artefacts should contribute to addressing the two flaws that are generally encountered during prototyping: overdesigning and overtrusting the prototypes.     

基于RFID普适计算环境的形式化上下文模型

提出了一个适合普适计算环境的、基于本体的形式化的上下文感知模型。该模型使用本体描述语言OWL描述上下文，采用层次化的设计方法，提高了上下文表达能力和快速上下文原型。为普适计算的上下文建模和应用、上下文重用和建立面向普适计算环境的软件基础设施提供了一种可行的方法。     

快速原型虚拟逼真设计原理及体系结构

在分析设计的特点和发展趋势的基础上,提出快速原型虚拟逼真设计,并对其特点和原理进行了讨论,快速原型虚拟逼真设计是面向并行工具,基于虚拟原型和虚拟环境仿真的设计,强调虚拟原型的快速生成和演化,在关键技术,原型系统以及开发环境三个层次上论述了快速原型虚拟逼真设计的研究,提出快速原型虚拟逼真设计模型以及基于该模型的体系结构。     

Human-centered approaches in geovisualization design: investigating multiple methods through a long-term case study

Working with three domain specialists we investigate human-centered approaches to geovisualization following an ISO13407 taxonomy covering context of use, requirements and early stages of design. Our case study, undertaken over three years, draws attention to repeating trends: that generic approaches fail to elicit adequate requirements for geovis application design; that the use of real data is key to understanding needs and possibilities; that trust and knowledge must be built and developed with collaborators. These processes take time but modified human-centred approaches can be effective. A scenario developed through contextual inquiry but supplemented with domain data and graphics is useful to geovis designers. Wireframe, paper and digital prototypes enable successful communication between specialist and geovis domains when incorporating real and interesting data, prompting exploratory behaviour and eliciting previously unconsidered requirements. Paper prototypes are particularly successful at eliciting suggestions, especially for novel visualization. Enabling specialists to explore their data freely with a digital prototype is as effective as using a structured task protocol and is easier to administer. Autoethnography has potential for framing the design process. We conclude that a common understanding of context of use, domain data and visualization possibilities are essential to successful geovis design and develop as this progresses. HC approaches can make a significant contribution here. However, modified approaches, applied with flexibility, are most promising. We advise early, collaborative engagement with data – through simple, transient visual artefacts supported by data sketches and existing designs – before moving to successively more sophisticated data wireframes and data prototypes.     

Prototypes and paratypes: designing mobile and ubiquitous computing applications

Conducting user-centered design is a primary challenge in ubiquitous computing. Two kinds of prototyping techniques can be particularly effective for developing mobile and ubiquitous computing applications: compound prototypes and situated experience prototypes. Compound prototypes combine the final product's user interface (UI) with a computational implementation that runs on a separate system without the resource constraints of the target device. This model lets researchers and designers evaluate a new application's physicality and aesthetics as well as its functionality. Situated experience prototypes, or paratypes, include experimental protocols that attempt to reproduce user interaction with the system in real situations, and can optionally use common prototyping instruments such as paper mock-ups or physical props. Using our Personal Audio Loop (PAL) project as a case study, we discuss how you can fruitfully employ compound prototypes and paratypes when designing and developing mobile and ubiquitous computing applications.     

Challenges and Promising Results in NoC Prototyping Using FPGAs

Although a significant amount of theoretical work supports the potential of NoC architectures, such results need to be demonstrated by actual implementations before the NoC paradigm becomes a reality. Besides demonstrating the feasibility of the overall approach, prototyping enables accurate evaluation of power, performance, area, and various design trade-offs. This article presents four NoC prototypes, discusses the challenges associated with their design, and assesses the potential of the NoC approach.