Automated transformations from UML behavior models to contracts

In model driven architecture （MDA）, system requirements are first captured by UML （unified mod- eling language） use cases with sequence diagrams to describe their intended use and implemented by classes of objected-oriented languages in the subsequent design stages. It is important that the dynamic behavior specified by the sequence diagrams is in full compliance with the implementation classes. This paper proposes an auto- matic approach and tool support for generating class contracts, which define a precondition and a postcondition for each operation of the class. The former serves as a guard to ensure invocations of the operations respect the semantics introduced by the sequence diagrams, and the latter places the system in a legal state to facilitate the succeeding operation calls. The contracts can be easily mapped to code of an object-oriented language such as Java. Thus, the approach helps to bridge the gap between the requirements and design stages of system development process. We use our model transformation tool to first generate a UML protocol state machine from the sequence diagrams, and then derive the contracts for a controller class. The transformations take into account the concurrency and critical constructs of the respective UML diagrams.     

Work domain analysis and sensors I: principles and simple example

In this paper we establish a foundation for understanding the instrumentation needs of complex dynamic systems if ecological interface design (EID)-based interfaces are to be robust in the face of instrumentation failures. EID-based interfaces often include configural displays which reveal the higher-order properties of complex systems. However, concerns have been expressed that such displays might be misleading when instrumentation is unreliable or unavailable. Rasmussen's abstraction hierarchy (AH) formalism can be extended to include representations of sensors near the functions or properties about which they provide information, resulting in what we call a “sensor-annotated abstraction hierarchy”. Sensor-annotated AHs help the analyst determine the impact of different instrumentation engineering policies on higher-order system information by showing how the data provided from individual sensors propagates within and across levels of abstraction in the AH. The use of sensor-annotated AHs with a configural display is illustrated with a simple water reservoir example. We argue that if EID is to be effectively employed in the design of interfaces for complex systems, then the information needs of the human operator need to be considered at the earliest stages of system development while instrumentation requirements are being formulated. In this way, Rasmussen's AH promotes a formative approach to instrumentation engineering.     

Automated support for modeling OO software

We explore how automated tools might support the dynamic modeling phase of object oriented software development. We use the Object Modeling Technique as a guideline and notational basis, but in principle our approach is not tied to any particular OO methodology. We assume, however, that dynamic modeling exploits scenarios (as in OMT) describing examples of using the system being developed. Our techniques can easily be adopted for various scenario representations, such as sequence diagrams or collaboration diagrams in UML     

Work domain analysis and sensors II: Pasteurizer II case study

In this paper we establish a foundation for understanding the instrumentation needs of complex dynamic systems if ecological interface design (EID)-based interfaces are to be robust in the face of instrumentation failures. EID-based interfaces often include configural displays which reveal the higher-order properties of complex systems. However, concerns have been expressed that such displays might be misleading when instrumentation is unreliable or unavailable. Rasmussen's abstraction hierarchy (AH) formalism can be extended to include representations of sensors near the functions or properties about which they provide information, resulting in what we call a “sensor-annotated abstraction hierarchy”. Sensor-annotated AHs help the analyst determine the impact of different instrumentation engineering policies on higher-order system information by showing how the data provided from individual sensors propagates within and across levels of abstraction in the AH. The use of sensor-annotated AHs with a configural display is illustrated with a simple water reservoir example. We argue that if EID is to be effectively employed in the design of interfaces for complex systems, then the information needs of the human operator need to be considered at the earliest stages of system development while instrumentation requirements are being formulated. In this way, Rasmussen's AH promotes a formative approach to instrumentation engineering.     

Application of principles of event related open systems to business process reengineering

This paper is focused on analysing the complete business environment with the help of information technology. It takes into account various interactions between different business processes while conducting BPR exercise. It also provides a framework based on event diagrams to record logical flow and other relevant details, which can be used for design of an information system. The event diagrams are useful for intelligent information system design. This methodology can also be used to develop a system for system design. Each event can be analysed for requirement of data, operations and resources. Interactions between various forces, events, modules, applications can be shown through interaction diagrams. The paper also lists out the driving forces for BPR and their contents.     

Towards an Integrated Graph Based Semantics for UML

Recently, we proposed an integrated formal semantics based on graph transformation for central aspects of UML class, object and state diagrams. In this paper, we explain the basic ideas of that approach and show how two more UML diagram types, sequence and collaboration diagrams, can be captured. For UML models consisting of a class diagram and particular state diagrams, a graph transformation system can be defined. Its graphs are associated with system states and its rules with operations in the class diagram and transitions in the state diagrams. Sequence and collaboration diagrams then characterize sequences of operation applications and therefore sequences of transformation rule applications. Thus valid sequence and collaboration diagrams correspond to derivations induced by the graph transformation system. Proceeding this way, it can be checked for example whether such an operation application sequence may be applied in a specific system state.     

A UML-Based Approach to System Testing

System testing is concerned with testing an entire system based on its specifications. In the context of object-oriented, UML development, this means that system test requirements are derived from UML analysis artifacts such as use cases, their corresponding sequence and collaboration diagrams, class diagrams, and possibly Object Constraint Language (OCL) expressions across all these artifacts. Our goal here is to support the derivation of functional system test requirements, which will be transformed into test cases, test oracles, and test drivers once we have detailed design information. In this paper, we describe a methodology in a practical way and illustrate it with an example. In this context, we address testability and automation issues, as the ultimate goal is to fully support system testing activities with high-capability tools.     

基于设计演算的形式化用例分析建模框架

提出一种形式化用例分析建模框架,引入类图、用例顺序图、用例状态图、功能规约函数和系统不变式从多个角度为需求建模.通过定义这些视图的形式化语义,为需求的各个方面定义了准确的形式化描述.利用该框架,可以从方法的交互行为规约和功能规约合成描述方法全部行为的全规约;也可以定义用例模型的性质,并通过设计演算中的证明来分析验证这些性质.作为应用,研究了检查用例模型一致性的规则.给出一个实例说明建模框架的可行性.     

An Initial Experimental Assessment of the Dynamic Modelling in UML

The goal of this empirical study is to compare the semantic comprehension of three different notations for representing the dynamic behaviour in unified modelling language (UML): (a) sequence diagrams, (b) collaboration diagrams, and (c) state diagrams. Eighteen students of Informatics analysed the three types of diagrams within three different application domains. We performed a 3 × 3 factorial experimental design with repeated measures. The metrics collected were total time and total score. The main conclusion of this study is that the comprehension of the dynamic modelling in object-oriented designs depends on the diagram type and on the complexity of the document. The software project design written in the UML notation is more comprehensible, when the dynamic behaviour is modelled in a sequence diagram. While if it is implemented using a collaboration diagram, the design turns out to be less comprehensible as the application domain, and consequently, the document is more complex.     

基于程序插装的动态测试技术实现

动态测试是检测程序的动态行为的一种有效手段,本文介绍了Safepro白盒软件测试工具系列中基于程序插装的动脉测试技术实现,具体讨论了动态测试的模型、数据流模型和动态跟踪数据的编码和解码技术,插装库设计与插装策略等内容。     

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.     

A UML-based quantitative framework for early prediction of resource usage and load in distributed real-time systems

This paper presents a quantitative framework for early prediction of resource usage and load in distributed real-time systems (DRTS). The prediction is based on an analysis of UML 2.0 sequence diagrams, augmented with timing information, to extract timed-control flow information. It is aimed at improving the early predictability of a DRTS by offering a systematic approach to predict, at the design phase, system behavior in each time instant during its execution. Since behavioral models such as sequence diagrams are available in early design phases of the software life cycle, the framework enables resource analysis at a stage when design decisions are still easy to change. Though we provide a general framework, we use network traffic as an example resource type to illustrate how the approach is applied. We also indicate how usage and load analysis of other types of resources (e.g., CPU and memory) can be performed in a similar fashion. A case study illustrates the feasibility of the approach.

Requirements specification via activity diagrams for agent-based systems

Goal-oriented agent systems are increasingly popular for developing complex applications that operate in highly dynamic environments. As with any software these systems have to be designed starting with the specification of system requirements. In this paper, we extend a popular agent design methodology, Prometheus, and improve the understandability and maintainability of requirements by automatically generating UML activity diagrams from existing requirements models; namely scenarios and goal hierarchies. This approach aims to overcome some of the ambiguity present in the current requirements specification in Prometheus and provide more structure for representing variations. Even though our approach is grounded in Prometheus, it can be generalised to all the methodologies that support similar notions in specifying requirements (i.e. notions of goals and scenarios). We present our approach and an evaluation based on user experiments. The evaluation showed that the activity diagram based approach enhances people’s understanding of the requirements, makes it easier to modify requirements, and easier to check them against the detailed design of the agents for coverage.     

Dynamic Meta Modeling with time: Specifying the semantics of multimedia sequence diagrams

The Unified Modeling Langugage (UML) offers different diagram types to model the behavior of software systems. In some domains like embedded real-time systems or multimedia systems, it is necessary to include specifications of time in behavioral models since the correctness of these applications depends on the fulfillment of temporal requirements in addition to functional requirements. UML thus already incorporates language features to model time and temporal constraints. Such model elements must have an equivalent in the semantic domain.We have proposed Dynamic Meta Modeling (DMM), an approach based on graph transformation, as a means for specifying operational semantics of dynamic UML diagrams. In this article, we extend this approach to also account for time by extending the semantic domain to timed graph transformation. This enables us to define the operational semantics of UML diagrams with time specifications. As an example, we provide semantics for special sequence diagrams from the domain of multimedia application modeling.     

Cost-weight trades for modular composite structures

A design approach for airframe structures is formulated based on the concept of modularity allowing trade-offs and optimization between cost and weight. A modular structure can be created by replacing a collection of parts which all have a unique design by a collection of parts where the same design repeats multiple times. Structures with high levels of modularity have higher weight since it is harder to design a weight-efficient structure when the amount of design options is limited, but this weight increase might be worth the associated decrease in manufacturing cost. In modular design, cost reductions are achieved through learning curve effects and through reduction of the non-recurring cost, for example, due to lower tooling costs. Based on dynamic programming, an approach to determine the optimum number of repeating designs was determined and applied to a composite fuselage structure. Two examples are given where the cost-weight efficiency at different modularity levels is assessed for a composite airframe: the stringers and the frames in a fuselage. The corresponding cost-weight diagrams indicated that the modularity concept provides a useful methodology for designing more cost- weight efficient structures. In both cases it was possible to replace a large amount of designs and increase the level of modularity of the structure, yielding significant reductions in recurring and non-recurring manufacturing costs while keeping the associated weight increase of the structure to a minimum.     

基于时序描述逻辑的UML顺序图形式化研究

在统一建模语言（UML）规范中顺序图的语义是以自然语言的形式描述的,是一种半形式化的语言,不能对系统的交互行为进行形式化分析及论证.针对UML顺序图缺乏精确的形式化描述问题,根据顺序图的时序特征,提出了增加交互操作符的UML顺序图的六元组形式化方法.对描述逻辑进行时序扩展,得到可表示动态和时序语义的形式化规范——时序描述逻辑.应用时序描述逻辑的时态算子得到时序描述逻辑语义形式的UML顺序图.用UML顺序图描述完整的C语言执行过程,将其形式化描述,实验结果表明,这种方法是可行的.     

Dynamic Meta Modeling with Time: Specifying the Semantics of Multimedia Sequence Diagrams

UML offers different diagram types to model behavior and dynamics of software systems. In some domains like embedded real-time systems or multimedia systems, it is necessary to include specifications of time since the correctness of these applications depends on the fulfillment of temporal requirements in addition to functional requirements. UML thus already incorporates language features to model time and temporal constraints. Such model elements must have an equivalent in the semantic domain. We have proposed Dynamic Meta Modeling (DMM) as a means for the specification of the formal operational semantics of UML models by applying graph transformation to the meta modeling of dynamic behavior. Within this paper, we extend this approach to also account for time by building on timed graph transformations. We apply these concepts to the domain of multimedia application modeling in which we adopt UML sequence diagrams. The DMM rules with time then specify an interpreter that can be used to analyze or test a model of multimedia sequence diagrams.     

基于动态切片和UML图的回归测试用例生成

针对基于UML设计的面向对象软件在修改后进行回归测试的情况,提出一种回归测试用例生成的新方法。获取软件修改后进行回归测试时必须重新测试的类和方法,分析与需要重测试类有关的UML顺序图,对顺序图中每个包含不等关系的条件断言生成与其有关的动态程序切片,根据该动态程序切片生成与其相应的回归测试用例。     

从UML顺序图生成状态图的一个方法

UML (Unified Modeling Language) is a visual modeling language used for specifying,visualizing,constructing,and documenting the artifacts of software systems by various diagrams.It has been widely accepted as a standard modeling language in both academic and industrial areas.UML sequence diagrams are mostly used in specifying system requirements.By representing interactions,which are arranged in time sequence,between the objects in a system,sequence diagrams can construct scenarios indicating the system‘‘s functions.A UML statechart diagram is a graph shows the sequences of states that an object or an interaction goes through during its life in response to received stimuli,together with its responses and actions.It‘‘s useful in the design stage of system development.This essay discusses the computer-aided transformation from sequence diagrams to statechart diagrams,which can offer strong support for the transfering from requirement analysis to system design in the software development process.With OCL (Object Control Language) semantic constrain,a transform algorithm is provided in the paper.And the differences with the related works are also mentioned.     

Synergistic verification and validation of systems and software engineering models

In this paper, we present a unified approach for the verification and validation of software and systems engineering design models expressed in UML 2.0 and SysML 1.0. The approach is based on three well-established techniques, namely formal analysis, programme analysis and software engineering (SwE) techniques. More precisely, our contribution consists of the synergistic combination of model checking, static analysis and SwE metrics that enables the automatic and efficient assessment of design models from static and dynamic perspectives. Additionally, we present the design and implementation of an automated computer-aided assessing framework integrating the proposed approach. Moreover, we discuss the related technical details and the underlying synergism. Finally, we illustrate the proposed approach by assessing a design case study that is composed of state machine and sequence diagrams.