基于人性化网站界面设计的用户建模

为了能够实现网站界面风格的人性化和和谐化,通过对部分用户的调查来研究用户因素和网页界面因素之间的相互关系,并从错综复杂的用户和网页界面因素中提取起决定性作用的因素。基于这些决定性因素,用神经网络的方法建立了一个用于个性化网站界面风格和布局设计的用户模型。利用所建立的模型设计了一个针对老年人的网页界面,经过测试验证,此模型能收到良好的效果,提高了用户对网站界面风格和布局的整体满意度。     

Standardizing the narrative of use cases: A controlled vocabulary of web user tasks

ContextFor user interfaces design, the use of appropriate terminology in writing use case narratives may determine the effectiveness of the design process, facilitating communication within multidisciplinary web development teams and leading to agreed designs.ObjectiveThis paper proposes a user task vocabulary for web user interface design. This vocabulary compiles terms related to the use of web applications, regardless of the application domain, as a way of standardizing the terminology used in the elaboration of use case narrative. The use of the vocabulary would help to reduce misunderstandings within multidisciplinary web development teams.MethodThe construction of the vocabulary is based on the combination of both committee and empirical approaches. Committee approaches rely on experts in designing web applications, while empirical ones are focused on analyzing content objects, such as interaction design patterns and use case narratives.ResultsThe final version of the monolingual controlled vocabulary of web user tasks compiles a total of 40 tasks; each of them has a key term and a definition of the interaction carried out by users. Additionally, 41 semantic relationships were collected and represented as synonyms. The vocabulary has been assessed through an expert evaluation, proving its correctness and completeness, and an usability evaluation checking the efficacy of the vocabulary.ConclusionThe language employed in use case narratives can determine the value of use cases for designing user interfaces. The usage of a controlled vocabulary may allow designers to elaborate unambiguous use case narratives as a way of creating consistent task models for designing web user interfaces.     

Combining human error verification and timing analysis: a case study on an infusion pump

The design of a human–computer interactive system can be unacceptable for a range of reasons. User performance concerns, for example the likelihood of user errors and time needed for a user to complete tasks, are important areas of consideration. For safety-critical systems it is vital that tools are available to support the analysis of such properties before expensive design commitment has been made. In this work, we give a unified formal verification framework for integrating two kinds of analysis: (1) predicting bounds for task-completion times via exhaustive state-space exploration, and (2) detecting user-error related design issues. The framework is based on a generic model of cognitively plausible behaviour that captures assumptions about cognitive behaviour decided through a process of interdisciplinary negotiation. Assumptions made in an analysis, including those relating to the performance consequences of users recovering from likely errors, are also investigated in this framework. We further present a novel way of exploring the consequences of cognitive mismatches, on both correctness and performance grounds. We illustrate our analysis approach with a realistic medical device scenario: programming an infusion pump. We explore an initial pump design and then two variations based on features found in real designs, illustrating how the approach identifies both timing and human error issues.     

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.     

Formal Methods in Designing Embedded Systems—the SACRES Experience

From automotive electronics to avionics, embedded systems are part of our everyday life, and developed societies are increasingly dependent on their reliability in operation. At the same time, current design practice is inadequate in coping with the challenge of constructing dependable embedded systems.SACRES is an experimental design environment aimed at the seamless development of embedded systems. It incorporates state-of-the-art industrial design tools and provides formal specification, model checking technology and validated code generation. These concepts have been integrated on the basis of the synchronous approach to reactive systems.As a result, synchronous compilation techniques have been enhanced, in particular as regards techniques for distributed code generation. Formal verification technology was advanced to increase efficiency, handle composed systems and cover some real-time aspects. The new approach of translation validation was developed and proven to work.Real bugs have been found even in well-tested models. It was demonstrated that a formal design including verification is often more efficient than testing. As a consequence, all user partners are committed to further introducing formal design and verification technology.This paper summarises the essential achievements of the project. It explains the results in terms of the basic ideas, the available tools and methodology, as well as the experience gained.     

Multi-ontology fusion and rule development to facilitate automated code compliance checking using BIM and rule-based reasoning

Code compliance checking plays a critical role that identifies substandard designs according to regulatory documents and promises the accuracy of the designs before construction. However, the traditional code compliance checking process relies heavily on human work. To help the users better understand the checking process, this study proposes a gray-box checking technique and a BIM-based (Building Information Modeling) automated code compliance checking methodology that leverages ontology. The proposed approach contains a code ontology, a designed model ontology, a merged ontology, a code compliance checking ontology, a set of mapping rules, and a set of checking rules. During the checking process, the ontologies provide knowledge bases, and the rules provide necessary logic. A five-step roadmap is proposed for code ontology development for domain experts. For the time being, pre-processing is applied to create the designed model ontology to achieve time saving. Next, an ontology mapping procedure between the code and the designed model ontology is executed to obtain the merged ontology. In the ontology mapping procedure, the mapping rules aim to mitigate the semantic ambiguity between design information and regulatory information and enrich building information's semantics. Subsequently, rule-based reasoning is applied based on the checking rules and the merged ontology for checking reports generation. Finally, according to Chinese building codes, an automated code compliance checking platform is implemented for real construction projects to validate the proposed methodology.     

Design of statistical databases: A methodology for the conceptual step

The aim of the conceptual step in database design is to describe data involving in the application in a formal and abstract way, without any concern to the specific model and language chosen for the implementation. In statistical applications, data are described at different levels of aggregation, from elementary facts of the reality to complex aggregations such as classifications, time series, indexes. The paper describes a methodology for conceptual design of statistical databases that provides the designer suitable strategies for defining such different levels of aggregation starting from user requirements, and checking the completeness, coherence and minimality of the conceptual schema at the different levels. The methodology makes use of two data models for the representation of data: for elementary data the Entity-Relationship model, widely used in database applications, and for summary data a new model is proposed, designed to be an effective trade-off between expressive power and simplicity of use.     

Multi-Objective Optimization Model for QoS-Enabled Web Service Selection in Service-Based Systems

Nowadays, the web service has become the emerging communication technology where the interaction of each user is performed through the World Wide Web. However, the performance of the web service mechanism is degraded due to security flaws that occur throughout the Internet.. The user or service requester may not attain the relevant web service for their requirement. To overcome this problem, the newly developed multi-objective based Cuckoo Search (MCS) algorithm is proposed in this article. Initially, the input query model was built by the query keyword that is provided by the service requester. Then, the given query is matched with the database that hosts the web services that relates to input query. Among the various services, the user has to select the appropriate web service using the proposed algorithm. The MCS algorithm is newly designed by combining the Cuckoo Search algorithm and the QoS parameter based multiple objectives. Additionally, the new mathematical model of fitness is evaluated by the multi-objective parameters. Finally, the proposed algorithm exploits the fitness value to select the relevant web service for the user query. The experimental results are validated and performance is analyzed by the parameters of precision, recall, and F-measure. Thus, 86.6% of precision value was obtained by the proposed method, which ensured provision of the appropriate web service.     

Parallel Cloud Service Selection and Ranking Based on QoS History

The growing number of cloud services has made service selection a challenging decision-making problem by offering wide ranging choices for cloud service consumers. This necessitates the use of formal decision making methodologies to assist a decision maker in selecting the service that best fulfills the user’s requirements. In this paper, we present a cloud service selection methodology that utilizes quality of service history of cloud services over different time periods and performs parallel multi-criteria decision analysis to rank all cloud services in each time period in accordance with user preferences before aggregating the results to determine the overall rank of all the available options for cloud service selection. This methodology assists the cloud service user to select the best possible available service according to the requirements. The multi-criteria decision making processes used for each time period are independent of the other time periods and are executed in parallel.     

A formal methodology for integral security design and verification of network protocols

In this work we propose a methodology for incorporating the verification of the security properties of network protocols as a fundamental component of their design. This methodology can be separated in two main parts: context and requirements analysis along with its informal verification; and formal representation of protocols and the corresponding procedural verification. Although the procedural verification phase does not require any specific tool or approach, automated tools for model checking and/or theorem proving offer a good trade-off between effort and results. In general, any security protocol design methodology should be an iterative process addressing in each step critical contexts of increasing complexity as result of the considered protocol goals and the underlying threats. The effort required for detecting flaws is proportional to the complexity of the critical context under evaluation, and thus our methodology avoids wasting valuable system resources by analyzing simple flaws in the first stages of the design process. In this work we provide a methodology in coherence with the step-by-step goals definition and threat analysis using informal and formal procedures, being our main concern to highlight the adequacy of such a methodology for promoting trust in the accordingly implemented communication protocols. Our proposal is illustrated by its application to three communication protocols: MANA III, WEP's Shared Key Authentication and CHAT-SRP.     

Friendly web services selection exploiting fuzzy formal concept analysis

This work describes a system for supporting the user in the discovery of semantic web services, taking into account personal requirements and preference. Goal is to model an ad-hoc service request by selecting conceptual terms rather than using strict syntax formats. Through a concept-based navigation mechanism indeed, the user discovers conceptual terminology associated to the web resources and uses it to generate an appropriate service request which syntactical matches the names of input/output specifications. The approach exploits the fuzzy formal concept analysis for modeling concepts and relative relationships elicited from web resources. After the request formulation and submission, the system returns the list of semantic web services that match the user query.     

Optimal design of controlled multibody dynamic systems for performance,robustness and tolerancing

The multidisciplinary design approach has gained increasing popularity in recent years due to its ability to deal with conflicting design requirements imposed by discipline-specific objectives. The traditional design process involving multiple disciplines is typically a sequential process where the design objectives are met one at a time in a sequence of designs. However, in doing so, unnecessary limitations are imposed on the design parameters and the final design is far from being optimal. The effectiveness of integrated design methodology has been proven and such designs are being obtained in many applications. However, most of the work in this area has been problem and/or system specific and does not address important manufacturing considerations, such as tolerance allocation, robustness with respect to machining tolerances, etc. The results presented in this paper are intended to contribution towards filling these gaps. In particular, the new approach will help designers avoid a common known pitfall of performance optimization, i.e. the fact that designs that are optimized for performance alone are notoriously sensitive to deviations from the nominal design. Thus, optimizing for performance alone leads to designs that fall below acceptable standards of robustness; they are also expensive to manufacture because the tolerances must be kept very tight to ensure acceptable performance. The approach presented here will allow the user to systematically tradeoff performance versus robustness and tolerancing concerns. A proof-of-concept example that was solved to evaluate this methodology is also presented in this paper. This example provides a convincing demonstration of the fact that small sacrifices in performance can yield huge benefits in the other areas, provided a methodology is available for making these tradeoffs in a systematic way. This especially can be used by designers in various fields such as automotive, aerospace, deployable structures, machine tools (including hexapods), robotic systems, precision machinery, etc.     

基于ACT-R模型的互联网交互模式库设计

论文以用户行为中心的交互设计理念,提出了基于AC T-R认知模型的新型交互模式库的组织方法,并给出相应的界面评估方法和界面效率。设计者可根据设计需求和关注点发掘交互模式,并参考模式对应的认知原则以及界面效率,对交互方案进行选择和优化。     

Model driven code checking

Model checkers were originally developed to support the formal verification of high-level design models of distributed system designs. Over the years, they have become unmatched in precision and performance in this domain. Research in model checking has meanwhile moved towards methods that allow us to reason also about implementation level artifacts (e.g., software code) directly, instead of hand-crafted representations of those artifacts. This does not mean that there is no longer a place for the use of high-level models, but it does mean that such models are used in a different way today. In the approach that we describe here, high-level models are used to represent the environment for which the code is to be verified, but not the application itself. The code of the application is now executed as is by the model checker, while using powerful forms of abstraction on-the-fly to build the abstract state space that guides the verification process. This model-driven code checking method allows us to verify implementation level code efficiently for high-level safety and liveness properties. In this paper, we give an overview of the methodology that supports this new paradigm of code verification.     

A methodology for user directed search in evolutionary design

A designer should be able to express their intentions with a design tool. This work describes a methodology that enables the architect to directly interact with the encoding of designs they find aesthetically pleasing. Broadening interaction beyond simple evaluation increases the amount of feedback and bias a user can apply to the search. Increased feedback will have the effect of directing the algorithm to more fruitful areas of the search space. We conduct trials on two interfaces for making localised changes to a design in order to evaluate if the user is capable of directing search. In addition, an examination of the locality of changes made by the users provides an insight into how they explore the search space. The results show that a suitably designed interface is capable of directing search and that the participants used different magnitudes of change during directed search.     

Efficient verification of railway infrastructure designs against standard regulations

In designing safety-critical infrastructures s.a. railway systems, engineers often have to deal with complex and large-scale designs. Formal methods can play an important role in helping automate various tasks. For railway designs formal methods have mainly been used to verify the safety of so-called interlockings through model checking, which deals with state change and rather complex properties, usually incurring considerable computational burden (e.g., the state-space explosion problem). In contrast, we focus on static infrastructure models, and are interested in checking requirements coming from design guidelines and regulations, as usually given by railway authorities or safety certification bodies. Our goal is to automate the tedious manual work that railway engineers do when ensuring compliance with regulations, through using software that is fast enough to do verification on-the-fly, thus being able to be included in the railway design tools, much like a compiler in an IDE. In consequence, this paper describes the integration into the railway design process of formal methods for automatically extracting railway models from the CAD railway designs and for describing relevant technical regulations and expert knowledge as properties to be checked on the models. We employ a variant of Datalog and use the standardized “railway markup language” railML as basis and exchange format for the formalization. We developed a prototype tool and integrated it in industrial railway CAD software, developed under the name RailCOMPLETE^®. This on-the-fly verification tool is a help for the engineer while doing the designs, and is not a replacement to other more heavy-weight software like for doing interlocking verification or capacity analysis. Our tool, through the export into railML, can be easily integrated with these other tools. We apply our tool chain in a Norwegian railway project, the upgrade of the Arna railway station.     

基于QtWebkit的浏览器视频插件的设计与实现

为了解决基于Webkit引擎的嵌入式浏览器不能播放网页中嵌套的视频文件的问题,设计了一种简单有效的视频播放插件模型。该设计区别于传统的NPAPI标准插件,通过继承Qt自带的控件类并重载其中的方法来实现该插件的注册,利用ffplay实现数据流的获取和解码显示,设计用户界面负责响应用户事件并控制ffplay的播放,并通过FIFO管道和状态机来实现播放界面和ffplay的通信。最后在嵌入式平台下实现了该设计。经工程实践表明,该方法行之有效,通过该插件能够流畅观看网页中的视频文件。     

The formal-CAFE methodology and model checking patterns in the specification of e-commerce systems

Electronic commerce is an important application that has evolved significantly recently. However, electronic commerce systems are complex and difficult to be correctly designed. Guaranteeing the correctness of an e-commerce system is not an easy task due to the great amount of scenarios where errors occur, many of them very subtle. In this work we presents a methodology that uses formal-method techniques, specifically symbolic model checking, to design electronic commerce applications and to automatically verify them. Also, a model checking pattern hierarchy has been developed—it specifies patterns to construct and verify the formal model of e-commerce systems. We consider this research the first step to the development of a framework, which will integrate the methodology, an e-commerce specification language based on business rules, and a model checker. Adriano Pereira received the B.S. and M.S. degrees in computer science in 2000 and 2002, respectively, and he is currently pursuing the Ph.D. degree in computer science from the Federal University of Minas Gerais, Belo Horizonte, Brazil. His current interests are on performance analysis and modeling of e-business and distributed systems, and formal methods. Mark Song received the B.S., M.S. and Ph.D. degrees in computer science from the Federal University of Minas Gerais, Belo Horizonte, Brazil. His current interests are on distributed systems and formal methods – especially BMC (Bounded Model Checking). Gustavo Franco received the B.S. and M.S. degrees in computer science in 2001 and 2004, respectively, from the Federal University of Minas Gerais, Belo Horizonte, Brazil. His research was on modeling the user behavior of e-business and distributed systems, and formal methods. Actually his current interests are on software engeneering and project management of IT projects.     

基于有界限模型检验的服务建模与自动组合

针对面向服务架构(SOA)体系的Web服务数量快速增长现状,为实现大规模服务场景下高效自动组合Web服务来满足用户复杂需求问题,提出一种基于有界模型检验的Web服务组合方法.其中,Web服务被建模为有限状态自动机,众多Web服务构成服务社区,Web服务组合需求由线性时态逻辑公式描述,通过有界模型检验器的系统化搜索,该方...