Scalable System-level CTI Testing through Lightweight Coarse-grained Coordination

We propose a solution to the problem of system-level testing of functionally complex communication systems based on lightweight coordination. The enabling aspect is here the adoption of a coarse-grained approach to test design, which is central to the scalability of the overall testing environment. This induces an understandable modelling paradigm of system-wide test cases which is adequate for the needs and requirements of industrial test engineers. The approach is coarse-grained in the sense that it renounces a detailed model of the system functionality (which would be unfeasible in the considered industrial setting). The coordination is lightweight in the sense that it allows a programming-free definition of system-level behaviours (in this case complex test cases) based on the coarse models of the functionalities. These features enable test engineers to graphically design complex test cases, which, in addition, can even be automatically checked for their intended purposes via model checking.     

基于用户会话的Web应用性能测试方法的研究

近年来,Web应用成为互联网时代基础设施中最重要的组成部分。随着互联网技术的不断进步以及使用用户数量的不断增长,Web应用也越发变得复杂。为了保证Web应用性能测试的有效性和真实性,提出一种利用服务器日志中的用户会话信息、结合经过序列匹配算法改进的层次凝聚算法来自动产生Web应用性能测试脚本的方法。提出的方法通过从服务器日志中提取出用户会话信息,分析用户真实的访问模式,通过聚类算法将同类型的用户访问模式进行聚集,自动产生相应的测试请求序列,生成测试集。相比于传统的基于录制/回访的测试方法,基于用户会话的性能测试方法通过对用户会话进行聚类分析,还原实际的用户访问模式,减少了设计测试用例时的人工参与,保证了测试结果的有效性和真实性。     

Dynamic systems modelling and development of robotic applications in a visual programming environment

In this paper we describe our approach to modelling dynamic systems behaviour and its application to an industrial environment. A complete programming environment is described through an account of the rationale and modus operandi of the system. Our objective is to help managers, designers, engineers and software developers to understand dynamic systems behaviour through modelling. Examples of systems modelling are given and an industrial application of the programming environment for automatic food handling involving machine vision, virtual sensors and robot manipulation control is described.     

Database design with user-definable modelling concepts

Modelling is an integral part of engineering processes. Consequently, database design for engineering applications should take into account the modelling concepts used by engineers. On the other hand, these applications exhibit a wide diversity of modelling concepts. Rather than consolidating these into one single semantic data model one should aim for correspondingly specialized semantic models. This paper takes a constructive approach to developing such specialized models by proposing an Extensible Semantic Model (ESM) as the basis for declaring specialized semantic data models. The paper introduces a computerized environment for database design based on an ESM, and discusses the consequences of the ESM for a number of design tools: the need for a formal definition of the notion of modelling concept in order to have reliable and precise foundation for the extensions, declarative techniques for quickly introducing graphical representations for new concepts and for using them during schema design, conceptual-level test data generation for a designer-oriented evaluation of designs, and optimization techniques to control the wide latitude in mapping a conceptual schema to a logical schema. First experiences seem to point to considerable productivity gains during database design.     

Performance modelling of a network processor using POOSL

The increasing complexity of innovative real-time hardware/software systems forced industry to consider system-level design methods. Before actually implementing a system with hardware and software components, system-level design methods enable analysing the performance of different design alternatives that realise the required functionality. In order to develop performance models early in the design process, the parallel object-oriented specification language (POOSL) can be used. POOSL is an expressive modelling language for analysing complex real-time distributed hardware/software systems. Being equipped with a formal semantics, POOSL ensures unambiguous execution of models and proper application of performance analysis techniques. This paper discusses the use of POOSL for analysing the performance of a network processor. A network processor consists of components that perform their behaviour in a synchronously concurrent way, whereas POOSL is based on an asynchronous modelling paradigm. In this paper, we illustrate that constructing abstract models of synchronous systems for the purpose of performance analysis may benefit from an asynchronous modelling approach.     

Flying Together: Modelling Air Mission Teams

The problem of modelling air missions is part of a larger problem—simulating possible war-like scenarios in the air, sea, and on land. In modelling such military systems one is required to model the behaviour of various actors and the resources that are available to them. One aspect of this problem is the modelling of a group of actors as a team and then modelling the coordinated behaviour of such a team to achieve a joint goal.In the domain of air mission modelling the actors are pilots who control aircraft and their behaviour is referred to as tactics. In this paper we present the approach we adopted in modelling teams and team tactics as part of the development of the Smart Whole AiR Mission Model (SWARMM) for the Air Operations Division of the Australian Defence Science and Technology Organization. In our approach teams are composed of sub-teams and adopt organizational structures. Such structures define the responsibilities of the sub-teams towards the mission to be achieved as well as towards the control and coordination of the sub-teams. We also describe how communication is used when adopting a variety of control and coordination strategies and how one could reason about the choice of organizational structures for a given mission and situation.     

An initial industrial evaluation of interactive search-based testing for embedded software

Search-based software testing promises the ability to generate and evaluate large numbers of test cases at minimal cost. From an industrial perspective, this could enable an increase in product quality without a matching increase in the time and effort required to do so.Search-based software testing, however, is a set of quite complex techniques and approaches that do not immediately translate into a process for use with most companies.For example, even if engineers receive the proper education and training in these new approaches, it can be hard to develop a general fitness function that covers all contingencies. Furthermore, in industrial practice, the knowledge and experience of domain specialists are often key for effective testing and thus for the overall quality of the final software system. But it is not clear how such domain expertise can be utilized in a search-based system.This paper presents an interactive search-based software testing (ISBST) system designed to operate in an industrial setting and with the explicit aim of requiring only limited expertise in software testing. It uses SBST to search for test cases for an industrial software module, while also allowing domain specialists to use their experience and intuition to interactively guide the search.In addition to presenting the system, this paper reports on an evaluation of the system in a company developing a framework for embedded software controllers. A sequence of workshops provided regular feedback and validation for the design and improvement of the ISBST system. Once developed, the ISBST system was evaluated by four electrical and system engineers from the company (the ‘domain specialists’ in this context) used the system to develop test cases for a commonly used controller module. As well as evaluating the utility of the ISBST system, the study generated interaction data that were used in subsequent laboratory experimentation to validate the underlying search-based algorithm in the presence of realistic, but repeatable, interactions.The results validate the importance that automated software testing tools in general, and search-based tools, in particular, can leverage input from domain specialists while generating tests. Furthermore, the evaluation highlighted benefits of using such an approach to explore areas that the current testing practices do not cover or cover insufficiently.     

Aerodynamic shape optimization of supersonic aircraft configurations via an adjoint formulation on distributed memory parallel computers

This work describes the application of a control theory-based aerodynamic shape optimization method to the problem of supersonic aircraft design. A high fidelity computational fluid dynamics (CFD) algorithm modelling the Euler equations is used to calculate the aerodynamic properties of complex three-dimensional aircraft configurations. The design process is greatly accelerated through the use of both control theory and parallel computing. Control theory is employed to derive the adjoint differential equations whose solution allows for the evaluation of design gradient information at a fraction of the computational cost required by previous design methods. The resulting problem is then implemented in parallel using a domain decomposition approach, an optimized communication schedule, and the Message Passing Interface (MPI) Standard for portability and efficiency. In our earlier studies, the serial implementation of this design method, was shown to be effective for the optimization of airfoils, wings, wing–bodies, and complex aircraft configurations using both the potential equation and the Euler equations. In this work, our concern will be to extend the methodologies such that the combined capabilities of these new technologies can be used routinely and efficiently in an industrial design environment. The aerodynamic optimization of a supersonic transport configuration is presented as a demonstration test case of the capability. A particular difficulty of this test case is posed by the close coupling of the propulsion/airframe integration.