A Survey of Top-Level Ontologies - to inform the ontological choices for a Foundation Data Model

The Centre for Digital Built Britain has been tasked through the Digital Framework Task Group to develop an Information Management Framework (IMF) to support the development of a National Digital Twin (NDT) as set out in “The Pathway to an Information Management Framework” (Hetherington, 2020). A key component of the IMF is a Foundation Data Model (FDM), built upon a top-level ontology (TLO), as a basis for ensuring consistent data across the NDT. This document captures the results collected from a broad survey of top-level ontologies, conducted by the IMF technical team. It focuses on the core ontological choices made in their foundations and the pragmatic engineering consequences these have on how the ontologies can be applied and further scaled. This document will provide the basis for discussions on a suitable TLO for the FDM. It is also expected that these top-level ontologies will provide a resource whose components can be harvested and adapted for inclusion in the FDM

MODE I FATIGUE AND FRACTURE OF THE CARBON FIBER REINFORCED POLYMER TO CONCRETE BONDED INTERFACE

As wet, lay-up fiber reinforced polymers (FRP) continue to gain popularity in the redesign and retrofit of reinforced concrete structures; it becomes imperative to fully define the interaction between these materials. Until recently, the main body of FRP research focused on the flexural and shear strengths of the FRP to reinforced concrete system. However, in order to fully determine the capabilities of the structural system, the ability of the FRP to reinforced concrete bond to transfer the loads must be thoroughly investigated. The preliminary research on defining the behavior of the FRP to concrete bond (deemed the interface in earlier studies) primarily used two types of testing methodologies, the double cantilever beam (DCCB) and the three point bending beam. Recently, the Single Contoured Cantilever Beam (SCCB) was proposed for materials that exhibit brittle failure and are weak in tension. The overreaching goal of the current study is to better define the behavior of the bonded interface of reinforced concrete and carbon fiber reinforced polymers (CFRP). The study will utilize the surface profile 3 (SP 3) as the finished substrate surface and ascertain its effect on the system as it pertains to Mode I fracture and fatigue. The work is presented as three main contributions (journal articles) that address fracture of the concrete to CFRP bonded interface, an analytical model (FE) of the SCCB system, and fatigue of the concrete to CFRP bonded interface. A limited study on durability of the interface subjected to Mode I fatigue is also presented in Appendix B. In Chapter 2, the fracture behavior of the bonded interface using the SP 3 surface profile is investigated. Nine specimens with varying compressive strengths were tested to failure. The analysis shows that the critical strain energy release rate is a function of both the compressive strength of concrete and the mix design. A comparison of the results to past works was utilized to validate the current study results. The third chapter presents an analytical study (finite element) for fracture of the concrete to CFRP bonded interface. The model utilizes the ABAQUS® defined cohesive element to model the delamination of the interface. The results illustrate the ability of the cohesive element to effectively model the interface with a two percent difference in critical load between the model and the lab results. The fourth chapter provides a foundational work on the fatigue life of the concrete to CFRP bond interface. For this objective, the SCCB was subjected to a cyclic loading of multiple loads for a load ratio of 0.5 and a frequency of five hertz. The results were then used to formulate a modified Paris Law equation for the prediction of fatigue life for the 0.5 load ratio and five hertz frequency. The resulting analysis provided the material constants of B and m as 2 x 10-8 and 3, respectively. Additionally, it was discovered that while shallower than fracture, the failure occurred predominantly in the substrate

The Influence of media displays and image quality attributes for HDR image reproductions

High Dynamic Range (HDR) photography has been in existence at least since the time of Ansel Adams, with his experiments using analog film and darkroom techniques for the production of black and white prints in the 1940\u27s (Ashbrook, 2010). This photographic method has the ability to provide a more accurate representation of a scene through a greater range of the light and dark areas captured in an image. In the mid-20th century HDR Photography it has continued to grow in popularity among those interested in photography wishing to optimize their resulting image beyond a more commonly used technique. Presently, the limitations of commonly available reproduction technologies can lead to unpredictable output results through media such as monitor displays and inkjet prints. The purpose of this research was to determine the influence of quality attributes and image content on the preference of display media for HDR image reproductions. To achieve this purpose, a psychophysical experiment was conducted of 38 observers with previous imaging related exposure. This part of the study consisted of HDR comparisons across both a monitor display device and inkjet prints. Through qualitative and quantitative methods, common trends were identified among observer responses. The results show that for inkjet prints are the most preferred for the output of HDR images, specifically when printed on a metallic substrate. Additionally, the content of displayed images can directly impact display preference depending on the viewer\u27s perception and relationship formed with the photographic image. When evaluating HDR images across two media platforms, quality attributes comprising of a strong influence towards preference are sharpness, naturalness, contrast and highlights while artifacts, physical qualities and shadows were found to have barely any influence. Within the attributes related to HDR, relationships between attributes are found to be significant regarding image evaluation, leading to areas of further research

Ontological foundations for structural conceptual models

In this thesis, we aim at contributing to the theory of conceptual modeling and ontology representation. Our main objective here is to provide ontological foundations for the most fundamental concepts in conceptual modeling. These foundations comprise a number of ontological theories, which are built on established work on philosophical ontology, cognitive psychology, philosophy of language and linguistics. Together these theories amount to a system of categories and formal relations known as a foundational ontolog

Lessons from a Restricted Turing Test

We report on the recent Loebner prize competition inspired by Turing's test of intelligent behavior. The presentation covers the structure of the competition and the outcome of its first instantiation in an actual event, and an analysis of the purpose, design, and appropriateness of such a competition. We argue that the competition has no clear purpose, that its design prevents any useful outcome, and that such a competition is inappropriate given the current level of technology. We then speculate as to suitable alternatives to the Loebner prize.Comment: 20 page

Barry Smith an sich

Festschrift in Honor of Barry Smith on the occasion of his 65th Birthday. Published as issue 4:4 of the journal Cosmos + Taxis: Studies in Emergent Order and Organization. Includes contributions by Wolfgang Grassl, Nicola Guarino, John T. Kearns, Rudolf Lüthe, Luc Schneider, Peter Simons, Wojciech Żełaniec, and Jan Woleński

Stability and Performance Metrics for Adaptive Flight Control

This paper addresses the problem of verifying adaptive control techniques for enabling safe flight in the presence of adverse conditions. Since the adaptive systems are non-linear by design, the existing control verification metrics are not applicable to adaptive controllers. Moreover, these systems are in general highly uncertain. Hence, the system's characteristics cannot be evaluated by relying on the available dynamical models. This necessitates the development of control verification metrics based on the system's input-output information. For this point of view, a set of metrics is introduced that compares the uncertain aircraft's input-output behavior under the action of an adaptive controller to that of a closed-loop linear reference model to be followed by the aircraft. This reference model is constructed for each specific maneuver using the exact aerodynamic and mass properties of the aircraft to meet the stability and performance requirements commonly accepted in flight control. The proposed metrics are unified in the sense that they are model independent and not restricted to any specific adaptive control methods. As an example, we present simulation results for a wing damaged generic transport aircraft with several existing adaptive controllers

A General Theory of Emergence in Engineered Systems

Engineered systems are designed to satisfy specific needs and produce explainable/predictable results. But despite this intent, engineered systems don’t always do what they are designed to do once they are implemented. Some engineered systems produce properties and behaviors that are not clearly explainable or predictable by the properties of their components. This is a problem recognized in government and private sectors as having broad ranging financial and security consequences. It is also the essence of the emergence phenomena. A review of the literature reveals two significant gaps in the current body of knowledge on emergence as it pertains to engineered systems: 1) no conceptual model that reconciles conflicting aspects of emergence; and 2) no explanation of system factors and their relationships that affect the occurrence of emergence. The gaps are addressed in this dissertation through research using a methodology that incorporates rationalist inductive methods with modeling & simulation frameworks. Where other research and models of emergence focus on entity or agent behavior; the research in this dissertation takes place from a systems perspective. The focus is on system level behaviors and system factors as they pertain to the occurrence of emergent effects. Generally accepted thermodynamic principles and axioms for chemical reactions are used to develop scientific analogies for factors in engineered systems. A theory is derived consisting of six factors that are determinants in a mathematical model of a tipping point at which emergent effects will occur in engineered systems: 1) interoperability; 2) concentration of components; 3) component degrees of freedom; 4) variety of system regulators; 5) rate of information received vs transmitted by the system; and 6) relative amount of information received by the system vs a threshold for change in the system configuration. The theory and its implications are explored in simulation experiments. Other products and contributions of the research include: a) an ontology of emergence concepts; b) a unifying definition of emergence; and c) a system dynamics model of emergence in engineered systems

GTTC Future of Ground Testing Meta-Analysis of 20 Documents

National research, development, test, and evaluation ground testing capabilities in the United States are at risk. There is a lack of vision and consensus on what is and will be needed, contributing to a significant threat that ground test capabilities may not be able to meet the national security and industrial needs of the future. To support future decisions, the AIAA Ground Testing Technical Committees (GTTC) Future of Ground Test (FoGT) Working Group selected and reviewed 20 seminal documents related to the application and direction of ground testing. Each document was reviewed, with the content main points collected and organized into sections in the form of a gap analysis current state, future state, major challenges/gaps, and recommendations. This paper includes key findings and selected commentary by an editing team