Computability Theory

Computability is one of the fundamental notions of mathematics, trying to capture the effective content of mathematics. Starting from Gödel’s Incompleteness Theorem, it has now blossomed into a rich area with strong connections with other areas of mathematical logic as well as algebra and theoretical computer science

University of San Diego News Print Media Coverage 2006.01

Printed clippings housed in folders with a table of contents arranged by topic.https://digital.sandiego.edu/print-media/1036/thumbnail.jp

University of San Diego News Print Media Coverage 2007.10

Printed clippings housed in folders with a table of contents arranged by topic.https://digital.sandiego.edu/print-media/1057/thumbnail.jp

Cultural Context-Aware Models and IT Applications for the Exploitation of Musical Heritage

Information engineering has always expanded its scope by inspiring innovation in different scientific disciplines. In particular, in the last sixty years, music and engineering have forged a strong connection in the discipline known as “Sound and Music Computing”. Musical heritage is a paradigmatic case that includes several multi-faceted cultural artefacts and traditions. Several issues arise from the analog-digital transfer of cultural objects, concerning their creation, preservation, access, analysis and experiencing. The keystone is the relationship of these digitized cultural objects with their carrier and cultural context. The terms “cultural context” and “cultural context awareness” are delineated, alongside the concepts of contextual information and metadata. Since they maintain the integrity of the object, its meaning and cultural context, their role is critical. This thesis explores three main case studies concerning historical audio recordings and ancient musical instruments, aiming to delineate models to preserve, analyze, access and experience the digital versions of these three prominent examples of musical heritage. The first case study concerns analog magnetic tapes, and, in particular, tape music, a particular experimental music born in the second half of the XX century. This case study has relevant implications from the musicology, philology and archivists’ points of view, since the carrier has a paramount role and the tight connection with its content can easily break during the digitization process or the access phase. With the aim to help musicologists and audio technicians in their work, several tools based on Artificial Intelligence are evaluated in tasks such as the discontinuity detection and equalization recognition. By considering the peculiarities of tape music, the philological problem of stemmatics in digitized audio documents is tackled: an algorithm based on phylogenetic techniques is proposed and assessed, confirming the suitability of these techniques for this task. Then, a methodology for a historically faithful access to digitized tape music recordings is introduced, by considering contextual information and its relationship with the carrier and the replay device. Based on this methodology, an Android app which virtualizes a tape recorder is presented, together with its assessment. Furthermore, two web applications are proposed to faithfully experience digitized 78 rpm discs and magnetic tape recordings, respectively. Finally, a prototype of web application for musicological analysis is presented. This aims to concentrate relevant part of the knowledge acquired in this work into a single interface. The second case study is a corpus of Arab-Andalusian music, suitable for computational research, which opens new opportunities to musicological studies by applying data-driven analysis. The description of the corpus is based on the five criteria formalized in the CompMusic project of the University Pompeu Fabra of Barcelona: purpose, coverage, completeness, quality and re-usability. Four Jupyter notebooks were developed with the aim to provide a useful tool for computational musicologists for analyzing and using data and metadata of such corpus. The third case study concerns an exceptional historical musical instrument: an ancient Pan flute exhibited at the Museum of Archaeological Sciences and Art of the University of Padova. The final objective was the creation of a multimedia installation to valorize this precious artifact and to allow visitors to interact with the archaeological find and to learn its history. The case study provided the opportunity to study a methodology suitable for the valorization of this ancient musical instrument, but also extendible to other artifacts or museum collections. Both the methodology and the resulting multimedia installation are presented, followed by the assessment carried out by a multidisciplinary group of experts

KINE[SIS]TEM'17 From Nature to Architectural Matter

Kine[SiS]tem – From Kinesis + System. Kinesis is a non-linear movement or activity of an organism in response to a stimulus. A system is a set of interacting and interdependent agents forming a complex whole, delineated by its spatial and temporal boundaries, influenced by its environment. How can architectural systems moderate the external environment to enhance comfort conditions in a simple, sustainable and smart way? This is the starting question for the Kine[SiS]tem’17 – From Nature to Architectural Matter International Conference. For decades, architectural design was developed despite (and not with) the climate, based on mechanical heating and cooling. Today, the argument for net zero energy buildings needs very effective strategies to reduce energy requirements. The challenge ahead requires design processes that are built upon consolidated knowledge, make use of advanced technologies and are inspired by nature. These design processes should lead to responsive smart systems that deliver the best performance in each specific design scenario. To control solar radiation is one key factor in low-energy thermal comfort. Computational-controlled sensor-based kinetic surfaces are one of the possible answers to control solar energy in an effective way, within the scope of contradictory objectives throughout the year.FC

A Multi-Material Approach to Beam Hardening Correction and Calibration in X-Ray Microtomography

PhDX-ray microtomogaphy is a non-clinical, non-destructive, and quantitative technique for determining three-dimensional mineral concentration distributions in variably radiolucent samples with a spatial resolution on the micron scale. For reasons of practicality, particularly for longterm studies, it is often not possible or desirable to utilise a monochromatic X-ray source and so microtomography using a conventional impact-source X-ray generator to produce a polychromatic photon beam is carried out instead. The use of photons of multiple energies causes the production of projection artefacts arising from preferential absorption, which impair the greyscale accuracy of the resulting reconstruction and the material concentration measurements that are derived from the linear attenuation coefficients (LACs). The purpose of the project described in this thesis is to identify weaknesses in the current method of beam hardening correction and to develop and test a tomographic calibration and projection processing method which may demonstrably improve the quality of current beam hardening correction methods as used with the MuCAT microtomography equipment, which provides a worldclass impact-source microtomography research and production facility at Barts and The London School of Medicine and Dentistry. An overview of the physical basis of X-ray computed tomography and X-ray microtomography is given from first principles, and examples of quantitative applications of the techniques, which generally depend on accurate reconstruction of linear attenuation coefficient values, are discussed. The major sources of artefacts in X-ray microtomography are discussed, particularly those with a direct impact on reconstructed linear attenuation coefficient values. Beam hardening is identified as an error source of particular interest, with secondary research on the effects of any beam hardening correction method on the severity of Compton scatter artefacts, and a critical review is carried out of historical attempts to reduce or mitigate these artefacts, particularly the single-material parameter-optimisation approach in service at the beginning of the research project. A ‘carousel’ test piece comprising multiple attenuators of multiple materials along with attenuation optimisation software based on varying multiple system parameters in order to extend the functionality and usability of the existing correction model, and qualitative results have so far been gathered suggesting the use of this system over the pre-existing attenuation wedge and parameter-optimisation method. A study of the effects of tuning the photon energy to which calibrations are made is carried out, showing improved linear attenuation coefficient recovery at a higher energy than was previously believed to be optimal, and a significant effect arising from X-ray generator target evaporation leading to spatial changes and time-dependence of the target thickness parameter is measured, suggesting that automated calibration as a standard part of the measurement process is required. A stability experiment is carried out using this method in order to examine the possibility of inconsistency resulting from ageing of the filament cathode, which is found not to significantly impact the quality of results. An immersion tank is developed in order to ensure beam hardening correction validity in the case of dual-material specimens where a radiodensity-matching fluid can be provided and the sample is suitable for immersion. Experimental comparison using a commercial beam hardening calibration device as the specimen reveals significantly improved hydroxyapatite concentration measurement recovery. An in-scatter experiment was carried out on the immersion tank, and it was found that there was a significant scatter contribution when the tank was filled in the case where the sample thickness is much less than the tank thickness. Proposals are presented for further work to improve reconstruction quality through of scatter reduction techniques in impactsource microtomographic systems, and to utilise the immersion tank for in situ chemical erosion experiments. The effects of the improvements to the beam hardening process are demonstrated using a biological specimen to demonstrate qualitative changes in reconstruction, particularly in improved dark levels surrounding the specimen. A second experiment is carried out in order to test the reproducibility of results, which is found to be improved by approximately four times over the same dataset corrected using the pre-existingbeam-hardening calibration methodEngineering and Physical Sciences Research Council grant number EP/G007845/1

Interior Materiality

The knowledge of materials and finishes is the bridge that links conceptual design to real-world application. It is among the core content of virtually all interior architecture/design curricula, moreover, access to up-to-date information on emerging technologies and trends is a key exigency for the contemporary designer. Accordingly, this book is authored to form a comprehensive resource for the “hows” and “whys” surrounding the functional and aesthetic contributions of a wide selection of materials and finishes used in multiple spatial design contexts. The knowledge base presented here is not only useful in shaping spatial experience, ensuring occupant well-being, and employing sustainable thinking but also beneficial in managing budget and schedule while enabling the delivery of top-quality work. The book investigates fundamental material properties, performance criteria, as well as sector-specific standards, regulations, and guidelines, with a special focus on concerns surrounding occupant health and safety as well as environmental impact and sustainability concerns. Furthermore, fabrication, installation, and maintenance issues were explored in detail. Various information collection and organization conventions are also discussed with regard to detailing, specification, estimation, and documentation of materials and finishes. The goals of the book can be listed as follows: ● Developing a vocabulary and knowledge base to comprehend and communicate concepts and paradigms associated with the history, classification, manufacturing, evaluation, fabrication, installation, and maintenance of materials and finishes. ● Identifying a broad range of materials and finishes, considering their aesthetic and performance properties, and understanding their utilization with regard to creative design intent, client expectations and requirements, user needs and experience, and incorporating life cycle implications. ● Providing a basis for achieving physical and psychological well-being for occupants, understanding the impact of changing social, cultural, economic, and ecological context, and eliminating negative environmental and social outcomes.https://newprairiepress.org/ebooks/1042/thumbnail.jp