Monitoring of Bridges using Computer Vision Methods

This paper is an overview of the development and application of Computer Vision for the Structural Health
Monitoring (SHM) of Bridges. A brief explanation of SHM is provided, followed by a breakdown of the stages of computer
vision techniques separated into laboratory and field trials. Qualitative evaluations and comparison of these methods have been
provided along with the proposal of guidelines for new vision-based SHM systems.

Field investigation of contactless displacement measurement using computer vision systems for civil engineering applications

Much of the bridge stock on major transport links in North America and Europe was constructed in the 1950s and 1960s and has since deteriorated or is carrying loads far in excess of the original design loads. Structural Health Monitoring Systems (SHM) can provide valuable information on the bridge capacity but the application of such systems is currently limited by access and bridge type. This paper investigates the use of computer vision systems for SHM. A series of field tests have been carried out to test the accuracy of displacement measurements using contactless methods. A video image of each test was processed using a modified version of the optical flow tracking method to track displacement. These results have been validated with an established measurement method using linear variable differential transformers (LVDTs). The results obtained from the algorithm provided an accurate comparison with the validation measurements. The calculated displacements agree within 2% of the verified LVDT measurements, a number of post processing methods were then applied to attempt to reduce this error.

Multiscale Analysis for Field-Effect Penetration through Two-Dimensional Materials

Gate-tunable two-dimensional (2D) materials-based quantum capacitors (QCs) and van der Waals heterostructures involve tuning transport or optoelectronic characteristics by the field effect. Recent studies have attributed the observed gate-tunable characteristics to the change of the Fermi level in the first 2D layer adjacent to the dielectrics, whereas the penetration of the field effect through the one-molecule-thick material is often ignored or oversimplified. Here, we present a multiscale theoretical approach that combines first-principles electronic structure calculations and the Poisson–Boltzmann equation methods to model penetration of the field effect through graphene in a metal–oxide–graphene–semiconductor (MOGS) QC, including quantifying the degree of “transparency” for graphene two-dimensional electron gas (2DEG) to an electric displacement field. We find that the space charge density in the semiconductor layer can be modulated by gating in a nonlinear manner, forming an accumulation or inversion layer at the semiconductor/graphene interface. The degree of transparency is determined by the combined effect of graphene quantum capacitance and the semiconductor capacitance, which allows us to predict the ranking for a variety of monolayer 2D materials according to their transparency to an electric displacement field as follows: graphene > silicene > germanene > WS2 > WTe2 > WSe2 > MoS2 > phosphorene > MoSe2 > MoTe2, when the majority carrier is electron. Our findings reveal a general picture of operation modes and design rules for the 2D-materials-based QCs.

Grounded Theory methods in child psychotherapy research

This article considers the place of qualitative research in psychoanalysis and child psychotherapy. It discusses why research methodology for many years occupied so small a place in these fields, and examines the cultural and social developments since the 1960s which have changed this situation, giving formal methods of research much greater significance. It reflects on the different pressures to develop formal research methods which arise both from outside the psychoanalytic field, as a condition of its continued professional survival, and from within it, where its main aim is the development of fundamental psychoanalytic knowledge, It suggests that the conduct of mainly quantitative research into treatment outcomes is largely a response to these external pressures, whilst the main benefits to be gained from the development of qualitative research methods, such as Grounded Theory, are in facilitating the knowledge-generating capacities and achievements of child psychotherapists themselves. The paper describes Grounded Theory methods, and explains how they can be valuable in the recognition of hitherto unrecognised meanings and patterns as these are made visible in clinical practice. Finally, it briefly describes five different examples of completed doctoral studies, all of which have added significantly to the knowledge-base of child psychotherapy, and which demonstrate how much can be accomplished using this method of research.

Objective Methods for Characterizing Physical Exposures which may contribute to Work-related Musculoskeletal Disorders in Agricultural Workers

Thesis (Ph.D.)--University of Washington, 2016-08

A comparative approach to web evaluation and website evaluation methods.

There is still a lack of an engineering approach for building Web systems, and the field of measuring the Web is not yet mature. In particular, there is an uncertainty in the selection of evaluation methods, and there are risks of standardizing inadequate evaluation practices. It is important to know whether we are evaluating the Web or specific website(s). We need a new categorization system, a different focus on evaluation methods, and an in-depth analysis that reveals the strengths and weaknesses of each method. As a contribution to the field of Web evaluation, this study proposes a novel approach to view and select evaluation methods based on the purpose and platforms of the evaluation. It has been shown that the choice of the appropriate evaluation method(s) depends greatly on the purpose of the evaluation.

Working with Student Teachers: A Mixed Methods Study to Examine the Roles and Self-Identified Dispositions of Cooperating Teachers

A critical component of teacher education is the field experience during which candidates practice under the supervision of experienced teachers. Programs use the InTASC Standards to define the requisite knowledge, skills, and dispositions for teaching. Practicing teachers are familiar with the concepts of knowledge and skills, but they are less familiar with dispositions. Practicing teachers who mentor prospective teachers are underrepresented in the literature, but they are critical to teacher preparation. The research goals were to describe the self-identified dispositions of cooperating teachers, identify what cooperating teachers consider their role in preparing prospective teachers, and explain challenges that cooperating teachers face. Using a mixed methods design, I conducted a quantitative survey followed by a qualitative case study. When I compared survey and case study data, cooperating teachers report possessing InTASC critical dispositions described in Standard 2: Learning Differences, Standard 3: Learning Environments, and Standard 9: Professional Learning and Ethical Practice, but not Standard 6: Assessment and Standard 10: Leadership and Collaboration. Cooperating teachers assume the roles of modeler, mentor and advisor, and informal evaluator. They explain student teachers often lack skills and dispositions to assume full teaching responsibilities and recommend that universities better prepare candidates for classrooms. Cooperating teachers felt university evaluations were not relevant to teaching reality. I recommend modifying field experiences to increase the quantity and duration of classroom placements. I suggest further research to detail cooperating teacher dispositions, compare cooperating teachers who work with different universities, and determine if cooperating teacher dispositions influence student teacher dispositions.

A comparison of in situ vs. ex situ filtration methods on the assessment of dissolved and particulate metals at hydrothermal vents

The objective of this study was to assess the impact of the filtration method (in situ vs. ex situ) on the dissolved/particulate partitioning of 12 elements in hydrothermal samples collected from the Lucky Strike vent field (Mid-Atlantic Ridge; MAR). To do so, dissolved ( <0.45 mu m) and particulate Mg, Li, Mn, U, V, As, Ba, Fe, Zn, Cd, Pb and Cu were measured using different techniques (HR-ICP-MS, ICP-AES and CCSA). Using in situ filtration as a baseline, we showed that ex situ filtration (on-board and on shore after freezing) resulted in an underestimation of the dissolved pool, which was counterbalanced by an overestimation of the particulate pool for almost all the elements studied. We also showed that on-board filtration was acceptable for the assessment of dissolved and particulate Mn, Mg, Li and U for which the measurement bias for the dissolved fraction did not exceed 3%. However, in situ filtration appeared necessary for the accurate assessment of the dissolved and particulate concentrations of V, As, Fe, Zn, Ba, Cd, Pb and Cu. In the case of Fe, on-board filtration underestimated the dissolved pool by up to 96%. Laboratory filtration (after freezing) resulted in a large bias in the dissolved and particulate concentrations, unambiguously discounting this filtration method for deep-sea chemical speciation studies. We discuss our results in light of the precipitation processes that can potentially affect the accuracy of ex situ filtration methods.

Numerical methods for solar tomography in the STEREO era

In this thesis, we propose several advances in the numerical and computational algorithms that are used to determine tomographic estimates of physical parameters in the solar corona. We focus on methods for both global dynamic estimation of the coronal electron density and estimation of local transient phenomena, such as coronal mass ejections, from empirical observations acquired by instruments onboard the STEREO spacecraft. We present a first look at tomographic reconstructions of the solar corona from multiple points-of-view, which motivates the developments in this thesis. In particular, we propose a method for linear equality constrained state estimation that leads toward more physical global dynamic solar tomography estimates. We also present a formulation of the local static estimation problem, i.e., the tomographic estimation of local events and structures like coronal mass ejections, that couples the tomographic imaging problem to a phase field based level set method. This formulation will render feasible the 3D tomography of coronal mass ejections from limited observations. Finally, we develop a scalable algorithm for ray tracing dense meshes, which allows efficient computation of many of the tomographic projection matrices needed for the applications in this thesis.

The development and field test of a Mealtime Interaction Clinical Observation Tool: a pilot study and clinical research portfolio

Objective: The purpose of this study was to develop and test psychometric properties of a Mealtime Interaction Clinical Observation Tool (MICOT) that could be used to facilitate assessment and behavioural intervention in childhood feeding difficulties. Methods: Thematic analysis of four focus groups with feeding and behaviour experts identified the content and structure of the MICOT. Following refinement, inter-rater reliability was tested between three healthcare professionals. Results: Six themes were identified for the MICOT, which utilises a traffic-light system to identify areas of strength and areas for intervention. Despite poor inter-rater reliability, for which a number of reasons are postulated, some correlation between psychologists’ ratings was evident. Healthcare professionals liked the tool and reported that it could have good clinical utility. Conclusion: The study provides a promising first version of a clinical observation tool that facilitates assessment and behavioural intervention in childhood feeding difficulties.

Good Practices in the field of Health Promotion and Chronic Disease Prevention

Background; Approach and Concept; Methods (Country reviews; Definition of Good Practice Criteria; Identification of Good Practice Examples; Identification of transferable practices / elements); Outputs

From the field to the table: ionizing radiation as a feasible postharvest treatment for fresh and dried plant foods

Food irradiation is a treatment that involves subjecting in-bulk or packaged food to a controlled dose of ionizing radiation, with a clearly defined goal. It has been used for disinfestation and sanitization of food commodities and to retard postharvest ripening and senescence processes, being a sustainable alternative to chemical agents 1 . Doses up to 10 kGy are approved by several international authorities for not offering negative effects to food from a nutrition and toxicology point of view 2 . However, the adoption of this technology for food applications has been a slow process due to some misunderstandings by the consumer who often chooses non-irradiated foods. In this study, the effects of the ionizing radiation treatment on physical, chemical and bioactive properties of dried herbs and its suitability for preserving quality attributes of fresh vegetables during cold storage were evaluated. The studied herbs, perennial spotted rockrose (Tuberaria lignosa (Sweet) Samp.) and common mallow (Malva neglecta Wallr.) were freeze-dried and then irradiated up to 10 kGy in a Cobalt-60 chamber. The selected vegetables, watercress (Nasturtium officinale R. Br.) and buckler sorrel (Rumex induratus Boiss. Reut.) were rinsed in tap water, packaged in polyethylene bags, submitted to irradiation doses up to 6 kGy and then were stored at 4 C for a period of up to 12 days. Physical, chemical and bioactive parameters of irradiated and non-irradiated samples were evaluated using different methodologies the colour was measured with a colorimeter, individual chemical compounds were analyzed by chromatographic techniques, antioxidant properties were evaluated using in vitro assays based on different reaction mechanisms, and other quality analyses were performed following official methods of analysis. The irradiation treatment did not significantly affect the colour of the perennial spotted rockrose samples, or its phenolic composition and antioxidant activity 3 . Medium doses preserved the colour of common mallow and a low dose did not induce any adverse effect in the organic acids profile. The green colour of the irradiated vegetables was maintained during cold storage but the treatment had pros and cons in other quality attributes. The 2 kGy dose preserved free sugars and favoured polyunsaturated fatty acids (PUFA) while the 5 kGy dose favoured tocopherols and preserved the antioxidant properties in watercress samples. The 6 kGy dose was a suitable option for preserving PUFA and the ω-6 ω-3 fatty acids ratio in buckler sorrel samples. This comprehensive experimental work allowed selecting appropriate processing doses for the studied plant foods in order to preserve its quality attributes and edibility.

Comparing concentration Methods: parasitrap® versus Kato-Katz for studying the prevalence of Helminths in Bengo province, Angola.

Background: Helminth intestinal parasitoses are responsible for high levels of child mortality and morbidity. Hence, the capacity to diagnose these parasitoses and consequently ensure due treatment represents a factor of great importance. Objectives: The main objective of this study involves comparing two methods of concentration, parasitrap and Kato-Katz, for the diagnosis of intestinal parasitoses in faecal samples. Methods: Sample processing made recourse to two different concentration Methods: the commercial parasitrap® method and the Kato-Katz method. Results: We correspondingly collected a total of 610 stool samples from pre-school and school age children. The results demonstrate the incidence of helminth parasites in 32.8% or 32.3% of the sample collected depending on whether the concentration method applied was either the parasitrap method or the Kato-Katz method. We detected a relatively high percentage of samples testing positive for two or more species of helminth parasites. We would highlight that in searching for larvae the Kato-Katz method does not prove as appropriate as the parasitrap method. Conclusion: Both techniques prove easily applicable even in field working conditions and returning mutually agreeing results. This study concludes in favour of the need for deworming programs and greater public awareness among the rural populations of Angola.