The development of a theoretical framework and design tool for process usability assessment

The purpose of usability engineering is to facilitate the deployment of new products by decreasing development costs and improving the quality of systems. This paper will discuss the development and delivery of a unique, theoretically based software tool that provides engineers and designers with easy access to the most recent advances in human-machine interface design. This research combines several theoretical views of the interaction process into a hybrid model. Based on this model, a software tool was produced that allows engineers to model the human interaction process within their design. The system then provides feedback on the interaction process through items such as: the amount of mental effort required by a user, the degree to which the system conforms to human capabilities, the expected time to complete the interaction, where potential human error may occur, as well as potential misunderstandings or points of confusion to the users. The designer may then use this information to improve the design of the system. Validation of this technique indicates that the hybrid model produces accurate predictions of usability attributes and that the technique transfers from the laboratory to the real world.     

Bridging patterns: An approach to bridge gaps between SE and HCI

Adding usability improving solutions during late stage development is to some extent restricted by the software architecture. However, few software engineers and human–computer interaction engineers are aware of this important constraint and as a result avoidable rework is frequently necessary. In this paper we present a new type of pattern called a bridging pattern. Bridging patterns extend interaction design patterns by adding information on how to generally implement this pattern. Bridging patterns can be used for architectural analysis: when the generic implementation is known, software architects can assess what it means in their context and can decide whether they need to modify the software architecture to support these patterns. This may prevent part of the high costs incurred by adaptive maintenance activities once the system has been implemented and leads to architectures with better support for usability.     

Towards useful and usable interaction design tools: CanonSketch

Despite all the effort dedicated to bringing better User-Centered Design (UCD) tools to market, current studies show that the industry is still dominated by tools that do not support the activities and workstyles of designers. Also, there is a growing need for interaction design tools aimed at software engineers, a problem related to bringing usability into the software engineering processes.

We propose a new workstyle model that can be effectively used to envision, design and evaluate a new generation of innovative interaction and software design tools, aimed at integrating usability and software engineering.

We illustrate the effectiveness of our model by describing a new tool, called CanonSketch, that was built in order to support UCD in terms of the dimensions in our workstyle model. We also describe an evaluation study aimed at contrasting paper prototyping with our tool as well as the level of workstyle support.     

Developing platform specific model for MPSoC architecture from UML-based embedded software models

In this paper, we describe a technique to design UML-based software models for MPSoC architecture, which focuses on the development of the platform specific model of embedded software. To develop the platform specific model, we define a process for the design of UML-based software model and suggest an algorithm with precise actions to map the model to MPSoC architecture. In order to support our design process, we implemented our approach in an integrated tool. Using the tool, we applied our design technique to a target system. We believe that our technique provides several benefits such as improving parallelism of tasks and fast-and-valid mapping of software models to hardware architecture.     

An integrated framework for the analysis of dependable interactive systems (IFADIS): Its tool support and evaluation

This paper discusses a method for the analysis of dependable interactive systems using model checking, and its support by a tool designed to make it accessible to a broader community. The method and the tool are designed to be of value to system engineers, usability engineers and software engineers. It has been designed to help usability engineers by making those aspects of the analysis relevant to them explicit while concealing those aspects of modelling and model checking that are not relevant. The paper presents the results of a user evaluation of the effectiveness of aspects of the tool and how it supports the proposed method. The tool was constructed while both authors worked in the Human Computer Interaction Group. Department of Computer Science, University of York, UK.     

Reliable behaviour simulation of product interface in mixed reality

The validation of a product interface is often a critical issue in the design process. Virtual reality and mixed reality (MR) are able to enhance the interactive simulation of the product human–machine interface (HMI), as these technologies allow engineers to directly involve end users in the usability assessment. This paper describes a MR environment specifically addressed to the usability evaluation of a product interface, which allows the simulation of the HMI behaviour using the same models and the same software employed by engineers during the design phase. Our approach is based on the run-time connection between the visualisation software and the simulators used for product design and analysis. In particular, we use Matlab/Simulink to model and simulate the product behaviour, and Virtools to create the interactive MR environment in which the end user can test the product. Thanks to this architecture, any modification done on the behaviour models is immediately testable in MR.     

A structured methodology for comparative evaluation of user interface designs using usability criteria and measures

Previous research in software ergonomics has indicated the importance of evaluating the usability of computer user interfaces. This paper presents a quantitative basis for selecting from among multiple alternative interfaces relative to multiple criteria of usability concern. The proposed model consists of two main phases: the prescreening phase and the evaluation phase. The prescreening phase involves expert judgment-based assessment with qualitative criteria. The first phase uses absolute measurement analytic hierarchy process (AHP) to filter possible alternative interfaces to a reasonable subset. The evaluation phase involves user-based assessment such as user testing, with quantitative criteria. The objective of the second phase is to evaluate a subset of alternatives using objective measures and to select the best alternative. A set of criteria and measures for evaluating the usability of computer software designs is presented. The proposed methodology is demonstrated in the interface design of a database system used to analyze trip cases information of nuclear power plant.Relevance to industry

There is currently a focus on the usability of interactive computer software. Software developers, interface designers or human factors engineers often confront the task of comparative evaluation among systems, versions or interface designs. The proposed methodology provides practitioners with a structured approach to select the best interface based on usability criteria and measures.     

Hybrid evaluation method for Korean Character input system in mobile phones

In this study, hybrid evaluation incorporating the Hick–Hyman law was proposed to predict input performance of a Korean input system applied to the number pads of mobile phones. The hybrid model, calculated based on the Hick–Hyman law, is a combination of reaction time (RT) and movement time (MT) model, which is a better model for predicting user performance than the conventional models that were used to assess Korean input system evaluation such as the Fitts' and the KLM-GOMS models. Along with Fitts' model (of visual-controlled movements), the simple movement time (SMT) and ballistic movement time (BMT) models (of ballistic behavior movement) were also evaluated to measure MT. Results showed that ballistic behavior movement was more compatible than visual-controlled movement. In ballistic behavior movement, a thumb-movement distance of <21 mm was closer to the SMT than the BMT model. These results indicate that when applying hybrid model movement, the displacement, and the target size properties of mobile phone users is required in the engineering of a predictive model. Thus, the suggested hybrid evaluation is meaningful in that it can evaluate users' input behaviors very appropriately in the case of hand-held input devices.Relevance to industryA hybrid model based on Hick–Hyman law was determined to be effective to evaluate text input systems for the hand-held input device. This effective hybrid model can provide more accurate prediction time for text input behaviors to its designers for efficient system design. To its usability engineers, this hybrid model for more accurate prediction time can also provide an effective quantitative tool for usability evaluations for hand-held input device manufacturing industries because this model can save efforts as well as time for usability testing.     

Guidelines for Eliciting Usability Functionalities

Like any other quality attribute, usability imposes specific constraints on software components. Features that raise the software system's usability have to be considered from the earliest development stages. But, discovering and documenting usability features is likely to be beyond the usability knowledge of most requirements engineers, developers, and users. We propose an approach based on developing specific guidelines that capitalize upon key elements recurrently intervening in the usability features elicitation and specification process. The use of these guidelines provides requirements analysts with a knowledge repository. They can use this repository to ask the right questions and capture precise usability requirements information.     

Experimental evaluation of software development tools for safety-critical real-time systems

Since the early years of computing, programmers, systems analysts, and software engineers have sought ways to improve development process efficiency. Software development tools are programs that help developers create other programs and automate mundane operations while bringing the level of abstraction closer to the application engineer. In practice, software development tools have been in wide use among safety-critical system developers. Typical application areas include space, aviation, automotive, nuclear, railroad, medical, and military. While their use is widespread in safety-critical systems, the tools do not always assure the safe behavior of their respective products. This study examines the assumptions, practices, and criteria for assessing software development tools for building safety-critical real-time systems. Experiments were designed for an avionics testbed and conducted on six industry-strength tools to assess their functionality, usability, efficiency, and traceability. The results some light on possible improvements in the tool evaluation process that can lead to potential tool qualification for safety-critical real-time systems.     

搜索问题的代数描述及其算法

文中给出了搜索问题的一种代数描述方法，在这种描述方法的基础上，给出了一个算法模式。以货郎担问题的动态规划－分支限界法为例，讨论了如何用所给出的算法模式来设计饱含多咱算法设计技术的算法，称这种算法为混合（ｈｙｂｒｉｄ）算法。还讨论了如何用面向对象的方法进行程序设计。这种求解问题的方法不仅为算法的自支生成提供了一种有力的工具，如果用面向对象的方法进行程序设计，还能提高代码的利用率。     

Using task analysis to improve usability of fatigue modelling software

The design of any interactive computer system requires consideration of both humans and machines. Software usability is one aspect of human–computer interaction that can benefit from knowledge of the user and their tasks. One set of methods for determining whether an application enables users to achieve their predetermined goals effectively and efficiently is task analysis. In the present study, a task analysis was applied to the graphical user interface of fatigue modelling software used in industry. The task analysis procedure allowed areas of usability improvement to be identified and then addressed with alternate interface prototypes. The present method of task analysis illustrates a practical and efficient way for software designers to improve software usability, user effectiveness and satisfaction, by involving users in the design process.     

Usability of product X-lessons from a real product

Using the example of a real product, this paper shows how various usability assessments, conducted by different human factors engineers, in several phases of the product's development life-cycle, identified similar potential usability problems. Circumstances dictated that no remedial action was taken, so it was possible to track these potential usability defects to customer sites, where it was found that most of the important problems did indeed occur. Thus, it can be demonstrated that human factors advice was valid and reliable. In simpler terms, early usability evaluation by human factors engineers can save hours of wasted development effort and customer frustration, and can help to ensure that a more usable product is produced.     

基于软件体系结构的构件组装工具ABC-Tool

软件朝着越来越复杂和庞大的趋势发展,因此对更有效的软件开发技术的需求十分迫切,近年来,软件体系结构、构件技术和软件复用技术等开始在软件开发中发挥重要作用,成为软件工程领域研究的热点,在基于构件复用的开发方法中,构件组装技术是关键,而且一直以来也是难点所在,ABC(architecture-based component composition)是一种基于软件体系结构、面向构件的软件开发方法,介绍了为ABC方法提供有效支持的工具ABC-Tool,ABC-Tool以软件体系结构为设计蓝图,以构件为基本开发单元,在不修改构件源代码的前提下,通过可视化的图形建模方式,从体系结构的高层设计逐层映射到底层实现,将可运行或可部署的构件组装为最终的可正确运行的系统。     

Supporting usability through software architecture

Software engineers should consider usability as a quality attribute in their architectural a designs. Usability determines how effectively and comfortably an end-user can achieve the goals that gave rise to an interactive system. It is an important attribute to consider during all phases of software design, but especially during architectural design because of the expense involved in adding usability aspects after users have tested the system. Since the 1980s, ongoing work on supporting usability through software architectural constructs has focused on the iterative design process for the user interface, which involves initial design, user testing, re-design to correct detected flaws, re-testing, and so on. The traditional software architectural response to repeated and expected modifications to the user interface is to use separation, encapsulation and information hiding to localize the user interface     

软件系统设计中人因工程的研究

设计一个经受起市场检验的软件系统,软件工程师的视野需要从“软件工程”的角度转变成“产品工程”的角度,即充分考虑产品使用者－－人的因素。为达到这个目的,针对软件系统设计中涉及的人的因素进行研究和探讨,重点探讨人因工程和软件系统设计结合的理论,并介绍一种系统设计中结合人的因素的有效工具－－CARMAN。     

Usability guideline for banking software design

As the diversity of services in the financial market increases, it is critical to design usable banking software in order to overcome the complex structure of the system. The current study presents a usability guideline based on heuristics and their corresponding criteria that could be used during the early stages of banking software design process. In the design of a usability guideline, the heuristics and their criteria are categorized in terms of their effectiveness in solving usability problems grouped and ranging from usability catastrophe to cosmetic problems. The current study comprises of three main steps: First, actual usability problems from three banking software development projects are categorized according to their severity level. Secondly, usability criteria are rated for how well they explain the usability problems encountered. Finally, usability heuristics are categorized according to the severity level of usability problems through two analytical models; corresponding and cluster analyses. As the result, designers and project managers may give more importance to the heuristics related with the following usability problem categories: Usability catastrophe and then major usability problems. Furthermore, the proposed guideline can be used to understand which usability criteria would be helpful in explaining usability problems as well as preventing banking system catastrophes, by highlighting the critical parts in system design of banking software.     

UML辅助化工过程模拟软件设计

面向对象技术是目前获得广泛应用的软件设计方法，在化工过程模拟领域也有大量应用。UML(United Model Language，统一建模语言)采用图形方式和基于静态样式的软件设计方式进行软件开发，可有效地解决化工模拟软件开发过程中软件开发人员与化工专业人员交流困难的问题，并可提高软件的复用程度和开发效率，是一种有效的面向对象的辅助设计工具。文中利用UML建立了化工过程单元和化工过程系统的对象模型。实践分析表明，利用UML辅助化工过程模拟软件设计可有效降低软件分析设计的难度，提高软件设计的质量和速度。     

Towards an empirical method of efficiency testing of system parts: A methodological study

Current usability evaluation methods are essentially holistic in nature. However, engineers that apply a component-based software engineering approach might also be interested in understanding the usability of individual parts of an interactive system. This paper examines the efficiency dimension of usability by describing a method, which engineers can use to test, empirically and objectively, the physical interaction effort to operate components in a single device. The method looks at low-level events, such as button clicks, and attributes the physical effort associated with these interaction events to individual components in the system. This forms the basis for engineers to prioritise their improvement effort. The paper discusses face validity, content validity, criterion validity, and construct validity of the method. The discussion is set within the context of four usability tests, in which 40 users participated to evaluate the efficiency of four different versions of a mobile phone. The results of the study show that the method can provide a valid estimation of the physical interaction event effort users made when interacting with a specific part of a device.