Understanding the Elements of Executable Architectures Through a Multi-Dimensional Analysis Framework

The objective of this dissertation study is to conduct a holistic investigation into the elements of executable architectures. Current research in the field of Executable Architectures has provided valuable solution-specific demonstrations and has also shown the value derived from such an endeavor. However, a common theory underlying their applications has been missing. This dissertation develops and explores a method for holistically developing an Executable Architecture Specification (EAS), i.e., a meta-model containing both semantic and syntactic information, using a conceptual framework for guiding data coding, analysis, and validation. Utilization of this method resulted in the description of the elements of executable architecture in terms of a set of nine information interrogatives: an executable architecture information ontology. Once the detail-rich EAS was constructed with this ontology, it became possible to define the potential elements of executable architecture through an intermediate level meta-model. The intermediate level meta-model was further refined into an interrogative level meta-model using only the nine information interrogatives, at a very high level of abstraction

Adding Executable Context to Executable Architectures: Enabling an Executable Context Simulation Framework (ECSF)

A system that does not stand alone is represented by a complex entity of component combinations that interact with each other to execute a function. In today\u27s interconnected world, systems integrate with other systems - called a system-of-systems infrastructure: a network of interrelated systems that can often exhibit both predictable and unpredictable behavior. The current state-of-the-art evaluation process of these system-of-systems and their community of practitioners in the academic community are limited to static methods focused on defining who is doing what and where. However, to answer the questions of why and how a system operates within complex systems-of-systems interrelationships, a system\u27s architecture and context must be observed over time, its executable architecture, to discern effective predictable and unpredictable behavior. The objective of this research is to determine a method for evaluating a system\u27s executable architecture and assess the contribution and efficiency of the specified system before it is built. This research led to the development of concrete steps that synthesize the observance of the executable architecture, assessment recommendations provided by the North Atlantic Treaty Organization (NATO) Code of Best Practice for Command and Control (C2) Assessment, and the metrics for operational efficiency provided by the Military Missions and Means Framework. Based on the research herein, this synthesis is designed to evaluate and assess system-of-systems architectures in their operational context to provide quantitative results

Application of Executable Architectures in Early Concept Evaluation

This research explores use of executable architectures to guide design decisions in the early stages of system development. Decisions made early in the system development cycle determine a majority of the total lifecycle costs as well as establish a baseline for long term system performance and thus it is vital to program success to choose favorable design alternatives. The development of a representative architecture followed the Architecture Based Evaluation Process as it provides a logical and systematic order of events to produce an architecture sufficient to document and model operational performance. In order to demonstrate the value in the application of executable architectures for trade space decisions, three variants of a fictional unmanned aerial system were developed and simulated. Four measures of effectiveness (MOEs) were selected for evaluation. Two parameters of interest were varied at two levels during simulation to create four test case scenarios against which to evaluate each variant. Analysis of the resulting simulation demonstrated the ability to obtain a statistically significant difference in MOE performance for 10 out of 16 possible test case-MOE combinations. Additionally, for the given scenarios, the research demonstrated the ability to make a conclusive selection of the superior variant for additional development

Executable system architecting using systems modeling language in conjunction with Colored Petri Nets - a demonstration using the GEOSS network centric system

Models and simulation furnish abstractions to manage complexities allowing engineers to visualize the proposed system and to analyze and validate system behavior before constructing it. Unified Modeling Language (UML) and its systems engineering extension, Systems Modeling Language (SysML), provide a rich set of diagrams for systems specification. However, the lack of executable semantics of such notations limits the capability of analyzing and verifying defined specifications. This research has developed an executable system architecting framework based on SysML-CPN transformation, which introduces dynamic model analysis into SysML modeling by mapping SysML notations to Colored Petri Net (CPN), a graphical language for system design, specification, simulation, and verification. A graphic user interface was also integrated into the CPN model to enhance the model-based simulation. A set of methodologies has been developed to achieve this framework. The aim is to investigate system wide properties of the proposed system, which in turn provides a basis for system reconfiguration --Abstract, page iii

A Time-Variant Value-Focused Methodology for Supporting Pre-Acquisition

Military operations are dynamic in nature, as time-dependent requirements or adversary actions can contribute to differing levels of mission performance among systems. Future military operations commonly use multi-criteria decision analysis techniques that rely on value-focused thinking (VFT) to analyze and ultimately rank alternatives during the Analysis of Alternatives phase of the acquisition process. Traditional VFT approaches are not typically employed with the intention of analyzing time-variant performance of alternatives. In this research, a holistic approach towards integrating fundamental practices such as VFT, systems architecture, and modeling and simulation is used to analyze time-dependent data outputs of an alternative’s performance within an operational environment. Incorporating this approach prior to Milestone A of the acquisition process allows for the identification of time-based capability gaps and additional dynamic analysis of possible alternatives that can be implemented as a flexible means of assessment. As part of this research, the pre-acquisition methodology is implemented with a hypothetical multi-domain Intelligence, Surveillance, and Reconnaissance mission in order to exemplify multiple time-dependent analysis possibilities

Force and Moment Measurements Applicable to a Flexible Weapons System

Continuing the development of the 6-DOF Motion Test Apparatus (MTA) for performing dynamic wind tunnel tests revealed the importance of a capable data acquisition (DAQ) system for collecting and analyzing data. Assembling and testing the DAQ system in conjunction with the MTA, AFIT Low-Speed Wind Tunnel, and a selection of high-performance sensors was the primary focus of this research. Specifically, acquiring time-accurate aerodynamic force and moment measurements on a variety of test models was of high importance. With the established real-time DAQ system hardware, a National Instruments (NI) LabVIEW program was created to acquire data from an ATI Nano25-E force transducer and a second LabVIEW program was modified to communicate with a MicroStrain® 3DM-GX4-15™ Inertial Measurement Unit (IMU). The complete DAQ hardware and software system was employed in both static and dynamic wind tunnel tests to collect the aerodynamic forces and moments acting on a NACA 0012 wing model. Dynamic testing involved pitch oscillation motions, which were tracked with the IMU, as well as pitch-plunge oscillation motions. Static tests yielded results that matched traditional sting mounted wind tunnel tests, despite minor angle-of-attack differences. Dynamic measurements of the lift, drag, and pitch moment coefficients were within expectations for the pitch oscillation tests and the highest ow velocity case of the pitch-plunge oscillation test

Model-Based Systems Engineering Approach to Distributed and Hybrid Simulation Systems

INCOSE defines Model-Based Systems Engineering (MBSE) as the formalized application of modeling to support system requirements, design, analysis, verification, and validation activities beginning in the conceptual design phase and continuing throughout development and later life cycle phases. One very important development is the utilization of MBSE to develop distributed and hybrid (discrete-continuous) simulation modeling systems. MBSE can help to describe the systems to be modeled and help make the right decisions and partitions to tame complexity. The ability to embrace conceptual modeling and interoperability techniques during systems specification and design presents a great advantage in distributed and hybrid simulation systems development efforts. Our research is aimed at the definition of a methodological framework that uses MBSE languages, methods and tools for the development of these simulation systems. A model-based composition approach is defined at the initial steps to identify distributed systems interoperability requirements and hybrid simulation systems characteristics. Guidelines are developed to adopt simulation interoperability standards and conceptual modeling techniques using MBSE methods and tools. Domain specific system complexity and behavior can be captured with model-based approaches during the system architecture and functional design requirements definition. MBSE can allow simulation engineers to formally model different aspects of a problem ranging from architectures to corresponding behavioral analysis, to functional decompositions and user requirements (Jobe, 2008)

-ilities Tradespace and Affordability Project – Phase 3

One of the key elements of the SERC’s research strategy is transforming the practice of systems engineering and associated management practices – “SE and Management Transformation (SEMT).” The Grand Challenge goal for SEMT is to transform the DoD community’s current systems engineering and management methods, processes, and tools (MPTs) and practices away from sequential, single stovepipe system, hardware-first, document-driven, point- solution, acquisition-oriented approaches; and toward concurrent, portfolio and enterprise- oriented, hardware-software-human engineered, model-driven, set-based, full life cycle approaches.This material is based upon work supported, in whole or in part, by the U.S. Department of Defense through the Office of the Assistant Secretary of Defense for Research and Engineering (ASD(R&E)) under Contract H98230-08- D-0171 (Task Order 0031, RT 046).This material is based upon work supported, in whole or in part, by the U.S. Department of Defense through the Office of the Assistant Secretary of Defense for Research and Engineering (ASD(R&E)) under Contract H98230-08- D-0171 (Task Order 0031, RT 046)

Application of Reliability and Linear Regression to Enterprise Architecture in Support of the US Air Force\u27s Capability Review and Risk Assessment

This research explored the use of modeling and enterprise architecture in the analysis of Air Force Capabilities. The Air Force accomplishes this through the Capability Review and Risk Assessment (CRRA). The CRRA is currently performed by building architectures which contain Process Sequence Models (PSMs). PSMs are scored by Subject Matter Experts to determine the probability of successfully completing the mission they model and ultimately to determine the risk associated to Air Force capabilities. Two findings were identified. The first is that creating additional architectural viewpoints, some of which are currently being proposed for version 2.0 of the DoD Architecture Framework, can benefit CRRA development. The second is PSMs have fundamental limitations associated with the inability to capture dependencies among activities as well as the inability to get beyond binary success criteria to address issues of capability sufficiency. To remedy these limitations a model called Extended Sequence Models (ESMs) was developed. ESMs extend PSMs by using reliability modeling techniques combined with linear regression to show dependencies between components. This model also allows the effects of capability sufficiency to be captured and related to mission success

A meta-semantic language for smart component-adapters

The issues confronting the software development community today are significantly different from the problems it faced only a decade ago. Advances in software development tools and technologies during the last two decades have greatly enhanced the ability to leverage large amounts of software for creating new applications through the reuse of software libraries and application frameworks. The problems facing organizations today are increasingly focused around systems integration and the creation of information flows. Software modeling based on the assembly of reusable components to support software development has not been successfully implemented on a wide scale. Several models for reusable software components have been suggested which primarily address the wiring-level connectivity problem. While this is considered necessary, it is not sufficient to support an automated process of component assembly. Two critical issues that remain unresolved are: (1) semantic modeling of components, and (2) deployment process that supports automated assembly. The first issue can be addressed through domain-based standardization that would make it possible for independent developers to produce interoperable components based on a common set of vocabulary and understanding of the problem domain. This is important not only for providing a semantic basis for developing components but also for the interoperability between systems. The second issue is important for two reasons: (a) eliminate the need for developers to be involved in the final assembly of software components, and (b) provide a basis for the development process to be potentially driven by the user. To resolve the above remaining issues (1) and (2) a late binding mechanism between components based on meta-protocols is required. In this dissertation we address the above issues by proposing a generic framework for the development of software components and an interconnection language, COMPILE, for the specification of software systems from components. The computational model of the COMPILE language is based on late and dynamic binding of the components\u27 control, data, and function properties. The use of asynchronous callbacks for method invocation allows control binding among components to be late and dynamic. Data exchanged between components is defined through the use of a meta- language that can describe the semantics of the information but without being bound to any specific programming language type representation. Late binding to functions is accomplished by maintaining domain-based semantics as component metainformation. This information allows clients of components to map generic requested service to specific functions