A metric for quantifying response time in a browser application

This paper presents to a performance quantification methodology for browser applications that operate in a distributed computing environment and are used in a nondeterministic way. It asserts that usability is intimately tied to response time, and that a single metric to quantify response time can be developed using probabilistic arguments. This metric incorporates both the delays inherent in the operation of a distributed application, and the observed frequency of each delay in order to create a single value that represents the responsiveness of the application     

An approach to usability evaluation of e-learning applications

Despite recent advances of electronic technologies in e-learning, a consolidated evaluation methodology for e-learning applications is not available. The evaluation of educational software must consider its usability and more in general its accessibility, as well as its didactic effectiveness. This work is a first step towards the definition of a methodology for evaluating e-learning applications. Specific usability attributes capturing the peculiar features of these applications are identified. A preliminary user study involving a group of e-students, observed during their interaction with an e-learning application in a real situation, is reported. Then, the proposal is put forward to adapt to the e-learning domain a methodology for systematic usability evaluation, called SUE. Specifically, evaluation patterns are proposed that are able to drive the evaluators in the analysis of an e-learning application.     

Accessibility,usability, and security evaluation of Hungarian government websites

Public sector bodies are increasingly relying on the Internet. On this channel, indispensable information is transmitted to the public and a wide range of services is already available. Therefore, the usability, accessibility, and the security of these websites are very important. Accessibility is particularly crucial for persons with disabilities. The accessibility of public service websites is regulated by a number of laws; among others, the directive “on the accessibility of the websites and mobile applications of public sector bodies” adopted by the European Parliament in 2016. This obliges all European Union member states to make all public sector websites and mobile applications accessible by 23 September 2021. In practice, this means that websites must fulfil the level AA recommendations in WCAG 2.1. In our study, a website assessment method is developed by comparing different analytical tools. With this method, we analysed how Hungarian websites of public sector bodies fulfil the requirements of the directive. We have also investigated how well they comply with usability and security guidelines. The results showed that none of the 25 websites of the examined Hungarian public sector bodies could completely fulfil the recommendations of the Web Content Accessibility Guidelines (WCAG) and that half of the websites had only the lowest level of compliance in usability tests. From the security point of view, almost half of the websites use outdated server versions and programming language, which is very critical. We have proposed several suggestions to address the major problems, so website developers and administrators can improve the accessibility, usability, and security aspects of these websites.

     

The ECORA framework: A hybrid architecture for context-oriented pervasive computing

An infrastructure approach to support context-aware pervasive computing is advantageous for rapid prototyping of context-aware distributed applications and beneficial for unifying modelling of context and reasoning in uncertain conditions. This paper presents the ECORA framework for context-aware computing, which is designed with a focus on reasoning about context under uncertainty and addressing issues of heterogeneity, scalability, communication and usability. The framework follows an agent-oriented hybrid approach, combining centralized reasoning services with context-aware, reasoning capable mobile software agents. The use of a centralized reasoning engine provides powerful reasoning capabilities and deploying context-aware mobile agents enables agility and robustness of components in the pervasive system. The design and implementation of the framework at different levels, as well as three case studies, are presented.     

Accessible user interface support for multi-device ubiquitous applications: architectural modifiability considerations

The market for personal computing devices is rapidly expanding from PC, to mobile, home entertainment systems, and even the automotive industry. When developing software targeting such ubiquitous devices, the balance between development costs and market coverage has turned out to be a challenging issue. With the rise of Web technology and the Internet of things, ubiquitous applications have become a reality. Nonetheless, the diversity of presentation and interaction modalities still drastically limit the number of targetable devices and the accessibility toward end users. This paper presents webinos, a multi-device application middleware platform founded on the Future Internet infrastructure. Hereto, the platform’s architectural modifiability considerations are described and evaluated as a generic enabler for supporting applications, which are executed in ubiquitous computing environments.     

Exploring the benefits of the combination of a software architecture analysis and a usability evaluation of a mobile application

Designing easy to use mobile applications is a difficult task. In order to optimize the development of a usable mobile application, it is necessary to consider the mobile usage context for the design and the evaluation of the user-system interaction of a mobile application. In our research we designed a method that aligns the inspection method “Software ArchitecTure analysis of Usability Requirements realizatioN” SATURN and a mobile usability evaluation in the form of a user test. We propose to use mobile context factors and thus requirements as a common basis for both inspection and user test. After conducting both analysis and user test, the results described as usability problems are mapped and discussed. The mobile context factors identified define and describe the usage context of a mobile application. We exemplify and apply our approach in a case study. This allows us to show how our method can be used to identify more usability problems than with each method separately. Additionally, we could confirm the validity and identified the severity of usability problems found by both methods. Our work presents how a combination of both methods allows to address usability issues in a more holistic way. We argue that the increased quantity and quality of results can lead to a reduction of the number of iterations required in early stages of an iterative software development process.     

Improving accessibility of Web interfaces: refactoring to the rescue

Universal access should be a target for all public Web sites. However, it is very hard to achieve, and even Web applications that comply with accessibility standards may still lack usability for disabled users. This paper proposes refactoring as an essencial technique to incrementally improve the accessibility and usability of a Web interface. Some accessibility refactorings are described and classified by the problems that each refactoring addresses. The way mainstream Web sites struggle with accessibility is illustrated, and two evaluations of email clients are presented as empirical evidence of the significance of accessibility refactorings at a low implementation cost.     

An authoring technology for multidevice Web applications

The rapid proliferation of mobile computing devices has increased the complexity and cost of cross-platform application development. Multidevice authoring technology (MDAT) lets developers build a generic application common to multiple devices and customize it for specific devices. We developed MDAT an end-to-end development methodology and toolset, to reduce the complexity of creating interactive, form-based Web applications that execute on heterogeneous devices. Web application refers to conventional, servlet-based Web applications as well as portlet applications. A portlet is a Web application component that a Web portal server aggregates with other portlets.     

基于网络的并行计算系统模型

随着Internet迅速发展,利用网上资源构筑分布式并行计算环境进行中、大粒度任务的分布式并行计算已呈现出重要研究价值。另外,Agent理论的日益成熟及多Agent系统MAS(Multi-Agent System)的出现,为开放式分布系统的开发和应用提供了新的模式。结合移动Agent在并行计算中的任务特性,对网络并行计算进行了抽象的分析和描述,然后给出了一个基于移动Agent计算的任务流模型实例。     

An espoused cultural perspective to understand continued intention to use mobile applications: a four-country study of mobile social media application usability

As most mobile applications are tailored for worldwide consumption, it is a significant challenge to develop applications that satisfy individuals with various cultural backgrounds. To address this issue, we drew on a recently developed conceptualization and associated instrument of mobile application usability to develop a model examining the impact of mobile social media application usability on continued intention to use. Drawing on Hofstede’s five cultural values, we incorporated espoused cultural values of masculinity/femininity, individualism/collectivism, power distance, uncertainty avoidance, and long-term orientation into our model as moderators. To test the model, we collected data from 1,844 consumers in four countries – the U.S., Germany, China, and India – who use mobile social media applications on their smartphones. The results provided support for the role of espoused national cultural values in moderating the impact of mobile social media application usability on continued intention to use and the model, with espoused cultural values explaining significantly more variance in continued intention to use (i.e., 38%) than the main effects-only model (i.e., 19%). Interestingly, our results demonstrated that culture at the national level did not play a significant role in affecting the relationship between usability constructs and continued intention to use, thus underscoring the importance of espoused culture.     

Can Convenience and Effectiveness Converge in Mobile Web? A Critique of the State-of-the-Art Adaptation Techniques for Web Navigation on Mobile Handheld Devices

Proliferation of mobile handheld devices and the significant advancement of wireless technologies and infrastructures have become a strong driving force of many mobile applications, including ubiquitous web information access through those devices. Despite the tremendous flexibility, accessibility, and convenience, rendering and navigating Web content on handheld devices suffer from significant usability problems attributable to their physical constraints, especially the small screen size, restricted interaction mechanisms, and low memory. Therefore, improving the effectiveness of web content navigation on those devices is crucial and has attracted increasing attention from both academics and industry. One of the promising solutions is adaptation, which focuses on the content restructuring, rearranging, and visualization. This article attempts to provide a comprehensive review of the state-of-the-art approaches to web adaptation for mobile handheld devices. The study not only categorizes, synthesizes, and compares the pros and cons of major adaptation methods but also discusses the observed problems in research methodology adopted in related studies and highlights future research directions. The article provides an important road map to the researchers and practitioners in this field.     

MobiByte: An Application Development Model for Mobile Cloud Computing

Mobile cloud computing presents an effective solution to overcome smartphone constraints, such as limited computational power, storage, and energy. As the traditional mobile application development models do not support computation offloading, mobile cloud computing requires novel application development models that can facilitate the development of cloud enabled mobile applications. This paper presents a mobile cloud application development model, named MobiByte, to enhance mobile device applications’ performance, energy efficiency, and execution support. MobiByte is a context-aware application model that uses multiple data offloading techniques to support a wide range of applications. The proposed model is validated using prototype applications and detailed results are presented. Moreover, MobiByte is compared with the most recent application models with a conclusion that it outperforms the existing application models in many aspects like energy efficiency, performance, generality, context awareness, and privacy.     

Use of force plate instrumentation to assess kinetic variables during touch screen use

Touch screens are becoming ubiquitous technology, allowing for enhanced speed and convenience of user interfaces. To date, the majority of touch screen usability studies have focused on timing and accuracy of young, healthy individuals. This information alone may not be sufficient to improve accessibility and usability of touch screens. Kinetic data (e.g. force, impulse, and direction) may provide valuable information regarding human performance during touch screen use. Since kinetic information cannot be measured with a touch screen alone, touch screen-force plate instrumentation, software, and methodology were developed. Individuals with motor control disabilities (Cerebral Palsy and Multiple Sclerosis), as well as gender- and age-matched non-disabled participants, completed a pilot reciprocal tapping task to evaluate the validity of this new instrumentation to quantify touch characteristics. Results indicate that the instrumentation was able to successfully evaluate performance and kinetic characteristics. The kinetic information measured by the new instrumentation provides important insight into touch characteristics which may lead to improved usability and accessibility of touch screens.     

Usability Principles for Augmented Reality Applications in a Smartphone Environment

Through the rapid spread of smartphones, users have access to many types of applications similar to those on desktop computer systems. Smartphone applications using augmented reality (AR) technology make use of users' location information. As AR applications will require new evaluation methods, improved usability and user convenience should be developed. The purpose of the current study is to develop usability principles for the development and evaluation of smartphone applications using AR technology. We develop usability principles for smartphone AR applications by analyzing existing research about heuristic evaluation methods, design principles for AR systems, guidelines for handheld mobile device interfaces, and usability principles for the tangible user interface. We conducted a heuristic evaluation for three popularly used smartphone AR applications to identify usability problems. We suggested new design guidelines to solve the identified problems. Then, we developed an improved AR application prototype of an Android-based smartphone, which later was conducted a usability testing to validate the effects of usability principles.     

Scheduling and development support in the Scavenger cyber foraging system

Cyber foraging is a pervasive computing technique where small mobile devices offload resource intensive tasks to stronger computing machinery in the vicinity.One of the main challenges within cyber foraging is that it is very difficult to develop cyber foraging enabled applications. An application using cyber foraging is working with mobile, distributed and, possibly, parallel computing; fields within computer science notoriously hard for programmers to grasp.This paper presents Scavenger—a cyber foraging system supporting easy development of mobile cyber foraging applications, while still delivering efficient, mobile use of remote computing resources through the use of a custom built mobile code execution environment and a new adaptive, dual-profiling scheduler.     

An integrated approach of MAS-CommonKADS,Model–View–Controller and web application optimization strategies for web-based expert system development

Web-based expert system development has been considered as complex, multidisciplinary and knowledge driven process. This paper presents a framework for development of web-based expert system with integrated approach of MAS-CommonKADS agent-oriented methodology, Model–View–Controller (MVC) architecture and web applications optimization strategies to deal with complexity of development and to achieve high usability. Study will guide in software engineering of developing such system with respect to Internet Technologies. Application of proposed framework for developing web-based expert system in sugarcane disorder diagnosis has been demonstrated. Results indicate that proposed methodology better deal with complexity of web-based expert system development and usability.     

基于J2ME和Agent的移动应用平台的设计

本文介绍了移动计算的特点,根据目前无线网络和移动设备应用程序设计的局限性,提出了基于J2ME+Agent的多线程的移动应用平台的设计方案,并引入了中间件思想。本文最后把该方案应用一个面向移动用户的云南省大型仪器协作共用网,从而证实了该平台在移动系统环境中具有较高的适应性和良好的使用性。     

Applying a methodology to develop user eXperience heuristics

A heuristic evaluation method allows the evaluation of the usability of application domains. To evaluate applications that have specific domain features, researchers can use sets of specific usability heuristics in addition to the well-known (usually Nielsen's) heuristics. Heuristics can also focus on the User eXperience (UX) aspects other than the usability. In a previous work, we proposed a formal methodology for establishing usability/UX heuristics. The methodology has 8 stages including activities to formulate, specify, validate and refine a new set of heuristics for a specific application domain. The methodology was validated through expert opinion and several case studies. Although when specifying the methodology, we explained each of its stages in detail, some activities can be difficult to perform without a guide that helps the researcher determine how the stages should be carried out. This article presents a detailed explanation regarding how to apply each stage of the methodology to create a new set of heuristics for a specific domain. Additionally, this paper explains how to iterate the methodology's stages and when to stop the process of developing new heuristics.     

Toward a Multidisciplinary Model of Context to Support Context-Aware Computing

Capturing, defining, and modeling the essence of context are challenging, compelling, and prominent issues for interdisciplinary research and discussion. The roots of its emergence lie in the inconsistencies and ambivalent definitions across and within different research specializations (e.g., philosophy, psychology, pragmatics, linguistics, computer science, and artificial intelligence). Within the area of computer science, the advent of mobile context-aware computing has stimulated broad and contrasting interpretations due to the shift from traditional static desktop computing to heterogeneous mobile environments. This transition poses many challenging, complex, and largely unanswered research issues relating to contextual interactions and usability. To address those issues, many researchers strongly encourage a multidisciplinary approach. The primary aim of this article is to review and unify theories of context within linguistics, computer science, and psychology. Summary models within each discipline are used to propose an outline and detailed multidisciplinary model of context involving (a) the differentiation of focal and contextual aspects of the user and application's world, (b) the separation of meaningful and incidental dimensions, and (c) important user and application processes. The models provide an important foundation in which complex mobile scenarios can be conceptualized and key human and social issues can be identified. The models were then applied to different applications of context-aware computing involving user communities and mobile tourist guides. The authors' future work involves developing a user-centered multidisciplinary design framework (based on their proposed models). This will be used to design a large-scale user study investigating the usability issues of a context-aware mobile computing navigation aid for visually impaired people.     

移动环境下基于移动代理的应用框架设计

随着网络技术的发展和移动设备的普及，用户希望能随时随地对资源进行访问。但是，由于移动网络连接带宽低且移动单元本身资源贫乏，移动环境为分布应用开发提出了新的挑战。移动代理技术以其节省带宽、异步性等特征，为移动计算提供了良好的解决方案。本文首先讨论了移动代理系统的设计，然后提出一个基于移动代理的移动应用框架
架，最后给出了相应的应用实例。