Goal-oriented requirements analysis and reasoning in the Tropos methodology

Tropos is an agent-oriented software methodology proposed in (J. Autonomous Agents Multi-Agent Syst. 8(3) (2004) 203; Inf. Syst. 27(6) (2002) 365). The methodology is founded on the notions of agent and goal, and goal analysis is used extensively to support software development during different phases. This paper adopts a formal goal model defined and analyzed in (J. Data Semantics 1 (2003); Proceedings of the International Conference on Advanced Information Systems Engineering, CAISE’04, vol. 3804 of LNCS, Springer, Berlin, 2004, pp. 20–33) to make the goal analysis process concrete through the use of forward and backward reasoning for goal models. The formal goal analysis is illustrated through examples, using an implemented goal reasoning tool.     

Specifying and analyzing early requirements in Tropos

We present a framework that supports the formal verification of early requirements specifications. The framework is based on Formal Tropos, a specification language that adopts primitive concepts for modeling early requirements (such as actor, goal, and strategic dependency), along with a rich temporal specification language. We show how existing formal analysis techniques, and in particular model checking, can be adapted for the automatic verification of Formal Tropos specifications. These techniques have been implemented in a tool, called the T-Tool, that maps Formal Tropos specifications into a language that can be handled by the NuSMV model checker. Finally, we evaluate our methodology on a course-exam management case study. Our experiments show that formal analysis reveals gaps and inconsistencies in early requirements specifications that are by no means trivial to discover without the help of formal analysis tools.

Computer-aided Support for Secure Tropos

In earlier work, we have introduced Secure Tropos, a requirements engineering methodology that extends the Tropos methodology and is intended for the design and analysis of security requirements. This paper briefly recaps the concepts proposed for capturing security aspects, and presents an implemented graphical CASE tool that supports the Secure Tropos methodology. Specifically, the tool supports the creation of Secure Tropos models, their translation to formal specifications, as well as the analysis of these specifications to ensure that they comply with specific security properties. Apart from presenting the tool, the paper also presents a two-tier evaluation consisting of two case studies and an experimental evaluation of the tool’s scalability.     

Multi-Agent Architectures as Organizational Structures

A Multi-Agent System (hereafter MAS) is an organization of coordinated autonomous agents that interact in order to achieve common goals. Considering real world organizations as an metaphor, this paper proposes architectural styles for MAS which adopt concepts from organizational theories. The styles are modeled in i*/Tropos, using the notions of actor, goal and actor dependency and are intended to capture needs/wants, delegations and obligations. The proposed architectural styles are evaluated with respect to a set of software quality attributes, such as predictability and adaptability. In addition, we report on a comparative study of organizational and conventional software architectures using a mobile robot control example from the Software Engineering literature. The research reported here was conducted within the scope of the Tropos project, whose objective is to develop a comprehensive agent-oriented software development methodology.     

A multi-agent legal recommender system

Infonorma is a multi-agent system that provides its users with recommendations of legal normative instruments they might be interested in. The Filter agent of Infonorma classifies normative instruments represented as Semantic Web documents into legal branches and performs content-based similarity analysis. This agent, as well as the entire Infonorma system, was modeled under the guidelines of MAAEM, a software development methodology for multi-agent application engineering. This article describes the Infonorma requirements specification, the architectural design solution for those requirements, the detailed design of the Filter agent and the implementation model of Infonorma, according to the guidelines of the MAAEM methodology.     

Engineering and verifying agent-oriented requirements augmented by business constraints with $${\mathcal{B}}$$-Tropos

We propose B{\mathcal{B}}-Tropos as a modeling framework to support agent-oriented systems engineering, from high-level requirements elicitation down to execution-level tasks. In particular, we show how B{\mathcal{B}}-Tropos extends the Tropos methodology by means of declarative business constraints, inspired by the ConDec graphical language. We demonstrate the functioning of B{\mathcal{B}}-Tropos using a running example inspired by a real-world industrial scenario, and we describe how B{\mathcal{B}}-Tropos models can be automatically formalized in computational logic, discussing formal properties of the resulting framework and its verification capabilities.     

面向Agent的软件开发方法及其评估

本文根据技术背景的差异,对已有面向Agent的软件开发方法进行了系统的分类,介绍了当前较有影响的一组代表性工作,分析和评估了各种方法的技术特点、适用范围及其存在的问题,概述了已有工具对面向Agent软件开发方法的支持;在参考国际上比较关注的面向Agent软件开发方法特性的基础上,提出了面向Agent软件开发方法的评估方法,对今后研究亟待解决的关键问题作了展望。     

类设计质量评估方法的研究

详细介绍了C&K度量方法,结合灰色关联分析的相关理论,提出了一种基于C&K度量方法和灰色关联分析的类设计质量评估方法。依据C&K度量阈值及可接受类的定义,可以推导出面向对象程序设计中的最佳类设计标准。将各个类与最佳类设计标准进行灰色关联分析,从而评估类设计质量的优劣。该方法为程序设计人员提供了类设计质量优劣的判定依据,并保证其在软件生命周期的早期阶段及时发现设计质量低劣的类并做相应的处理,避免后期开发的软件产品出现故障,能显著提高软件产品的可靠性和可维护性。     

基于Tropos~+需求模型的软件自适应方法

在模型驱动的软件自适应控制过程中,监测、分析、决策和执行等活动均基于共享的知识模型。为便于知识重用和运行时维护,常采用抽象级别较高的需求模型来表示知识。为建模软件的适应性需求,针对传统的Tropos及其扩展方法不能用于软件对异常事件适应性需求建模问题,对Tropos进行上下文和异常条件扩展,记为Tropos+。在此基础上,提出一种由Tropos+需求模型驱动的软件自适应方法,该方法能够用于软件运行环境和异常事件监测以及软件对环境变化和异常事件的自适应处理。最后通过一个案例说明了软件自适应过程。     

The Gaia Methodology for Agent-Oriented Analysis and Design

This article presents Gaia: a methodology for agent-oriented analysis and design. The Gaia methodology is both general, in that it is applicable to a wide range of multi-agent systems, and comprehensive, in that it deals with both the macro-level (societal) and the micro-level (agent) aspects of systems. Gaia is founded on the view of a multi-agent system as a computational organisation consisting of various interacting roles. We illustrate Gaia through a case study (an agent-based business process management system).     

STRATUM: A METHODOLOGY FOR DESIGNING HEURISTIC AGENT NEGOTIATION STRATEGIES

Automated negotiation is a powerful (and sometimes essential) means for allocating resources among self-interested autonomous software agents. A key problem in building negotiating agents is the design of the negotiation strategy, which is used by an agent to decide its negotiation behavior. In complex domains, there is no single, obvious optimal strategy. This has led to much work on designing heuristic strategies, where agent designers usually rely on intuition and experience. In this article, we introduce STRATUM, a methodology for designing strategies for negotiating agents. The methodology provides a disciplined approach to analyzing the negotiation environment and designing strategies in light of agent capabilities and acts as a bridge between theoretical studies of automated negotiation and the software engineering of negotiation applications. We illustrate the application of the methodology by characterizing some strategies for the Trading Agent Competition and for argumentation-based negotiation.     

Challenges and Research Directions in Agent-Oriented Software Engineering

Agent-based computing is a promising approach for developing applications in complex domains. However, despite the great deal of research in the area, a number of challenges still need to be faced (i) to make agent-based computing a widely accepted paradigm in software engineering practice, and (ii) to turn agent-oriented software abstractions into practical tools for facing the complexity of modern application areas. In this paper, after a short introduction to the key concepts of agent-based computing (as they pertain to software engineering), we characterise the emerging key issues in multiagent systems (MASs) engineering. In particular, we show that such issues can be analysed in terms of three different scales of observation, i.e., in analogy with the scales of observation of physical phenomena, in terms of micro, macro, and meso scales. Based on this characterisation, we discuss, for each scale of observation, what are the peculiar engineering issues arising, the key research challenges to be solved, and the most promising research directions to be explored in the future.     

A Method for Developing Component-Oriented Applications: A Use-Context Driven Approach Toward Component Coordination

In this paper, we propose a methodology for the development of component-oriented applications based on the Component Coordination Model (CCM) that is embedded into applications during software architecture design. The method is general enough to support the conceptual level of component-based software development. It provides a set of guidelines that ease developers during analysis and design phases. These guidelines are defined as processes for developing increasingly detailed models of constructing software systems. The CCM is driven by the use-context model, which directly reflects the role model that abstracts system behaviors as a computational organization comprising various role relationships. It then focuses on exposing the design of software components to be separated from their execution contexts. These separate concerns, including computation, coordination, and policies imposed on a given use-context, form the principal concept of our approach. A case study using the proposed method has been demonstrated in order to provide the feasibility of the introduced approach.     

Information system analysis and conceptual database design in production environments with M1

A methodology, called M¹, for information system analysis and database design of production environments is presented in detail. The originality of M¹ is to recognize the importance of integrating factory analysis methods for data and user requirements definition with logical database design methods for database specification. M¹ is a pragmatic, complete, manual methodology involving three major phases: Enterprise Modelling and Analysis which is the phase devoted to accurate analysis of the structure of the enterprise and precise definition of the scope of the future database application; Conceptual Design which is the phase concerned with data modelling of both static and dynamic properties of the enterprise; and Implementation Design which is the phase dealing with adaptation of the conceptual schema to the data model specifications of the physical database system used for application development and tuning performances of the physical system. The methodology is explained and illustrated by means of an example related to a Flexible Manufacturing System for mechanical parts.     

Interdigitation for effective design space exploration using iSIGHT

Optimization studies for nonlinear constrained problems (i.e. most complex engineering design problems) have repeatedly shown that (i) no single optimization technique performs best for all design problems, and (ii) in most cases, a mix of techniques perform better than a single technique for a given design problem. iSIGHT^TM is a generic software framework for integration, automation, and optimization of design processes that has been developed on the foundation of interdigitation: the strategy of combining multiple optimization algorithms to exploit their desirable aspects for solving complex problems. With the recent paradigm shift from traditional optimization to design space exploration for evaluating “what-if” scenarios and trade-off studies, iSIGHT has grown from an optimization software system to a complete design exploration environment, providing a suite of design exploration tools including a collection of optimization techniques, design of experiments techniques, approximation methods, and probabilistic quality engineering methods. Likewise, the interdigitation design methodology embodied in iSIGHT has grown to support the interdigitation of all design exploration tools for effective design space exploration. In this paper we present an overview of iSIGHT, past and present, of the interdigitation design methodology and its implementation for multiple design exploration tools, and of an industrial case study for which elements of this methodology have been applied. Received December 30, 2000     

A platform-based design framework for joint SW/HW multiprocessor systems design

We present P-Ware, a framework for joint software and hardware modelling and synthesis of multiprocessor embedded systems. The framework consists of (1) component-based annotated transaction-level models for joint modelling of parallel software and multiprocessor hardware, and (2) exploration-driven methodology for joint software and hardware synthesis. The methodology has the advantage of combining real-time requirements of software with efficient optimization of hardware performance. We describe and apply the methodology to synthesize a scheduler of a H264 video encoder on the Cake multiprocessor. Moreover, experiments show that the framework is scalable while achieving rapid and efficient designs.     

Development of a software library of functions for analysis of spatial mechanisms

An integrated method for symbolical derivation of Eqs and numerical computations using dual numbers for analysis of spatial mechanisms is presented in this paper. The formulation is based on 3×3 dual transformation matrices and derived symbolically using the Mathematica ^TM software package. Based on the solution procedure presented in this paper, a software library of functions for displacement analysis of spatial mechanisms has been developed. Functions in this software library can be readily used in theC ^H language environment, where dual number is treated as a first-class object. Displacement analysis of the RCRCR spatial mechanisms is used as an example to illustrate the solution procedure and programming details.     

Architectural-level risk analysis using UML

Risk assessment is an essential part in managing software development. Performing risk assessment during the early development phases enhances resource allocation decisions. In order to improve the software development process and the quality of software products, we need to be able to build risk analysis models based on data that can be collected early in the development process. These models will help identify the high-risk components and connectors of the product architecture, so that remedial actions may be taken in order to control and optimize the development process and improve the quality of the product. In this paper, we present a risk assessment methodology which can be used in the early phases of the software life cycle. We use the Unified Modeling Language (UML) and commercial modeling environment Rational Rose Real Time (RoseRT) to obtain UML model statistics. First, for each component and connector in software architecture, a dynamic heuristic risk factor is obtained and severity is assessed based on hazard analysis. Then, a Markov model is constructed to obtain scenarios risk factors. The risk factors of use cases and the overall system risk factor are estimated using the scenarios risk factors. Within our methodology, we also identify critical components and connectors that would require careful analysis, design, implementation, and more testing effort. The risk assessment methodology is applied on a pacemaker case study.