Domain specific software architectures: Command and control

GTE is the Command and Control contractor for the Domain Specific Software Architectures program. The objective of this program is to develop and demonstrate an architecture-driven, component-based capability for the automated generation of command and control (C2) applications. Such a capability will significantly reduce the cost of C2 applications development and will lead to improved system quality and reliability through the use of proven architectures and components. A major focus of GTE's approach is the automated generation of application components in particular subdomains. Our initial work in this area has concentrated in the message handling subdomain; we have defined and prototyped an approach that can automate one of the most software-intensive parts of C2 systems development. This paper provides an overview of the GTE team's DSSA approach and then presents our work on automated support for message processing

Quality traceability for user-centric context-aware systems in intelligent environments

Context-awareness is an important component of modern software systems. For example, in Ambient Assisted Living (AAL), the concept of context-awareness empowers users by reducing their dependence on others. Due to this role in healthcare, such systems need to be reliable and usable by their intended users. Our research addresses the development, testing and validation of context-aware systems in an emerging field which currently lacks sufficient systems engineering processes and disciplines. One specific issue being that developers often focus on delivering a system that works at some level, rather than engineering a system that meets a specified set of system requirements and their corresponding qualities. Our research aims to contribute towards improving the delivery of system quality by tracing, developing and linking systems development data for requirements, contexts including sensors, test cases and their results, and user validation tests and their results. We refer to this approach as the “quality traceability of context-aware systems”. In order to support the developer, the quality traceability of context-aware systems introduces a systems development approach tailored to context-aware systems in intelligent environments, an automated system testing tool and system validation process. We have implemented a case study to inform the research. The case study is in healthcare and based on an AAL system used to remotely monitor and manage, in real time, an individual prone to depressive symptoms

Strategies for the intelligent selection of components

It is becoming common to build applications as component-intensive systems - a mixture of fresh code and existing components. For application developers the selection of components to incorporate is key to overall system quality - so they want the `best\u27. For each selection task, the application developer will de ne requirements for the ideal component and use them to select the most suitable one. While many software selection processes exist there is a lack of repeatable, usable, exible, automated processes with tool support. This investigation has focussed on nding and implementing strategies to enhance the selection of software components. The study was built around four research elements, targeting characterisation, process, strategies and evaluation. A Post-positivist methodology was used with the Spiral Development Model structuring the investigation. Data for the study is generated using a range of qualitative and quantitative methods including a survey approach, a range of case studies and quasiexperiments to focus on the speci c tuning of tools and techniques. Evaluation and review are integral to the SDM: a Goal-Question-Metric (GQM)-based approach was applied to every Spiral

The Development of the Use of Expert Testimony

The steadily increasing performance of modern computer systems is having a large influence on simulation technologies. It enables increasingly detailed simulations of larger and more comprehensive simulation models. Increasingly large amounts of numerical data are produced by these simulations. This thesis presents several contributions in the field of mechanical system simulation and visualisation. The work described in the thesis is of practical relevance and results have been tested and implemented in tools that are used daily in the industry i.e., the BEAST (BEAring Simulation Tool) tool box. BEAST is a multibody system (MBS) simulation software with special focus on detailed contact calculations. Our work is primarily focusing on these types of systems. focusing on these types of systems. Research in the field of simulation modelling typically focuses on one or several specific topics around the modelling and simulation work process. The work presented here is novel in the sense that it provides a complete analysis and tool chain for the whole work process for simulation modelling and analysis of multibody systems with detailed contact models. The focus is on detecting and dealing with possible problems and bottlenecks in the work process, with respect to multibody systems with detailed contact models. The following primary research questions have been formulated: How to utilise object-oriented techniques for modelling of multibody systems with special reference tocontact modelling? How to integrate visualisation with the modelling and simulation process of multibody systems withdetailed contacts. How to reuse and combine existing simulation models to simulate large mechanical systems consistingof several sub-systems by means of co-simulation modelling? Unique in this work is the focus on detailed contact models. Most modelling approaches for multibody systems focus on modelling of bodies and boundary conditions of such bodies, e.g., springs, dampers, and possibly simple contacts. Here an object oriented modelling approach for multibody simulation and modelling is presented that, in comparison to common approaches, puts emphasis on integrated contact modelling and visualisation. The visualisation techniques are commonly used to verify the system model visually and to analyse simulation results. Data visualisation covers a broad spectrum within research and development. The focus is often on detailed solutions covering a fraction of the whole visualisation process. The novel visualisation aspect of the work presented here is that it presents techniques covering the entire visualisation process integrated with modeling and simulation. This includes a novel data structure for efficient storage and visualisation of multidimensional transient surface related data from detailed contact calculations. Different mechanical system simulation models typically focus on different parts (sub-systems) of a system. To fully understand a complete mechanical system it is often necessary to investigate several or all parts simultaneously. One solution for a more complete system analysis is to couple different simulation models into one coherent simulation. Part of this work is concerned with such co-simulation modelling. Co-simulation modelling typically focuses on data handling, connection modelling, and numerical stability. This work puts all emphasis on ease of use, i.e., making mechanical system co-simulation modelling applicable for a larger group of people. A novel meta-model based approach for mechanical system co-simulation modelling is presented. The meta-modelling process has been defined and tools and techniques been created to fully support the complete process. A component integrator and modelling environment are presented that support automated interface detection, interface alignment with automated three-dimensional coordinate translations, and three dimensional visual co-simulation modelling. The integrated simulator is based on a general framework for mechanical system co-simulations that guarantees numerical stability

From Domain Models to Components - A Formal Transformation Approach Towards Dependable Software Development

Many academic, industrial, and government research units have unanimously acknowledged the importance of developing dependable software systems. At the same time they have also concurred on the difficulties and challenges to be surmounted in achieving the goal. The importance of domain analysis and linking domain models to software artifacts were also recognized by various researchers. However, no formal approach to domain analysis was attempted. The primary motivation for this thesis stems from this context. Component-based software engineering offers some attractive mechanisms to tackle the inherent complexity in developing dependable systems. Recently a formal approach has been put forth for such a development. This thesis provides a formal approach for domain analysis, and transforms the domain model to components desired by this development process. Formal Concept Analysis (FCA) is a mathematical theory for identifying and classifying concepts. This thesis taps its potential to formally analyze the domain in a software development context. It turns out that the approach presented in this thesis cannot be fully automated; nevertheless several useful contributions have been made. These include (1) capturing formal concepts and defining them in FCA; (2) defining composition rules to categorize formal concepts and their trustworthy properties; (3) integrating partial formal context tables to build the concept lattice; (4) specifying and developing a model transformation approach to construct trustworthy OWL ontology; (5) implementing a model transformation technique to generate the TADL specification of the reusable component-based system. The proposed approach is applied to CoCoME, as a benchmark case study in the domain of component-based development

An Integrated Framework of Drivetrain Degradation Assessment and Fault Localization for Offshore Wind Turbines

As wind energy proliferates in onshore and offshore applications, it has become significantly important to predict wind turbine downtime and maintain operation uptime to ensure maximal yield. Two types of data systems have been widely adopted for monitoring turbine health condition: supervisory control and data acquisition (SCADA) and condition monitoring system (CMS). Provided that research and development have focused on advancing analytical techniques based on these systems independently, an intelligent model that associates information from both systems is necessary and beneficial. In this paper, a systematic framework is designed to integrate CMS and SCADA data and assess drivetrain degradation over its lifecycle. Information reference and advanced feature extraction techniques are employed to procure heterogeneous health indicators. A pattern recognition algorithm is used to model baseline behavior and measure deviation of current behavior, where a Self-organizing Map (SOM) and minimum quantization error (MQE) method is selected to achieve degradation assessment. Eventually, the computation and ranking of component contribution to the detected degradation offers component-level fault localization. When validated and automated by various applications, the approach is able to incorporate diverse data resources and output actionable information to advise predictive maintenance with precise fault information. The approach is validated on a 3 MW offshore turbine, where an incipient fault is detected well before existing system shuts down the unit. A radar chart is used to illustrate the fault localization result

A Model-Based AI-Driven Test Generation System

Achieving high software quality today involves manual analysis, test planning, documentation of testing strategy and test cases, and development of automated test scripts to support regression testing. This thesis is motivated by the opportunity to bridge the gap between current test automation and true test automation by investigating learning-based solutions to software testing. We present an approach that combines a trainable web component classifier, a test case description language, and a trainable test generation and execution system that can learn to generate new test cases. Training data was collected and hand-labeled across 7 systems, 95 web pages, and 17,360 elements. A total of 250 test flows were also manually hand-crafted for training purposes. Various machine learning algorithms were evaluated. Results showed that Random Forest classifiers performed well on several web component classification problems. In addition, Long Short-Term Memory neural networks were able to model and generate new valid test flows

Robotic path planning for non-destructive testing - a custom MATLAB toolbox approach

The requirement to increase inspection speeds for non-destructive testing (NDT) of composite aerospace parts is common to many manufacturers. The prevalence of complex curved surfaces in the industry provides motivation for the use of 6 axis robots in these inspections. The purpose of this paper is to present work undertaken for the development of a KUKA robot manipulator based automated NDT system. A new software solution is presented that enables flexible trajectory planning to be accomplished for the inspection of complex curved surfaces often encountered in engineering production. The techniques and issues associated with conventional manual inspection techniques and automated systems for the inspection of large complex surfaces were reviewed. This approach has directly influenced the development of a MATLAB toolbox targeted to NDT automation, capable of complex path planning, obstacle avoidance, and external synchronization between robots and associated external NDT systems. This paper highlights the advantages of this software over conventional off-line-programming approaches when applied to NDT measurements. An experimental validation of path trajectory generation, on a large and curved composite aerofoil component, is presented. Comparative metrology experiments were undertaken to evaluate the real path accuracy of the toolbox when inspecting a curved 0.5 m2 and a 1.6 m2 surface using a KUKA KR16 L6-2 robot. The results have shown that the deviation of the distance between the commanded TCPs and the feedback positions were within 2.7 mm. The variance of the standoff between the probe and the scanned surfaces was smaller than the variance obtainable via commercial path-planning software. Tool paths were generated directly on the triangular mesh imported from the CAD models of the inspected components without need for an approximating analytical surface. By implementing full external control of the robotic hardware, it has been possible to synchronise the NDT data collection with positions at all points along the path, and our approach allows for the future development of additional functionality that is specific to NDT inspection problems. For the current NDT application, the deviations from CAD design and the requirements for both coarse and fine inspections, dependent on measured NDT data, demand flexibility in path planning beyond what is currently available from existing off-line robot programming software

Fuzzy based component reusability evaluation approach to support component based software development

One of the contributions of Component Based Software Development (CBSD) is the reuse of software components across multiple systems by software developers. However, the developers often face a difficulty to determine the reusability of the components during the component selection process. Similarly, the component developers also have a problem to measure the component reusability during component development. Nowadays, even though many studies have been conducted in this field, which the researchers suggested many approaches with metrics but they still lack in empirical confirmation and evidences. Therefore, the aim of this study is to investigate and develop the component reusability evaluation approach to support CBSD. The proposed approach, which is called Component Reusability Evaluation Approach (CREA), is supported by the developed automated tool (CREATool) that may automate the reusability evaluation. CREA is then evaluated by applying five Java component in this approach and CREATool to the selected software components. The results from the application approach and then validated with results from the controlled experiment using statistical analysis. The results indicated that CREA able to provide an acceptable reusability measure, which it is confirmed by similarity results between evaluation using statistical analysis through the controlled experiment and by applying the CREATool. It shows that the proposed approach could be used as an alternative approach in component reusability evaluation. Although the developed approach are not intended to make a holistic and an ultimate decision whether the components can be reused or not, but it is useful enough to be considered as a guide for both component users and developers in making decisions related to reusable components