cometadata/datacite-rtg-text-other-reclassification-records huggingface dataset:
Regional Assessment of Glacier Motion in Kluane National Park, Yukon Territory
Creators: name: Waechter, Alexandra
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2013
Subjects: Yukon Territory
Kaskawulsh Glacier
Hubbard Glacier
St. Elias Icefield
speckle tracking
glacier velocity
Radarsat-2

description: This project presents regional velocity measurements for the eastern portion of the St. Elias Mountains, including the entire glaciated area of Kluane National Park, derived from speckle tracking of Radarsat-2 imagery acquired in winter 2011 and 2012. This technique uses a cross-correlation approach to determine the displacement of the ‘speckle’ pattern of radar phase returns between two repeat-pass images. Further reconstruction of past velocities is performed on a selection of key glaciers using feature tracking of Landsat-5 imagery, allowing for the investigation of variability in glacier motion on interannual and decadal time scales. The results of the analysis showed that there is a strong velocity gradient across the region reflecting high accumulation rates on the Pacific-facing slope of the mountain range. These glaciers may have velocities an order of magnitude greater than glaciers of a similar size on the landward slope. Interannual variability was high, both in relation to surge events, of which a number were identified, and variation of other unknown controls on glacier motion. A long-term trend of velocity decrease was observed on the Kaskawulsh Glacier when comparing the results of this analysis to work carried out in the 1960s, the pattern of which is broadly congruent to measurements of surface elevation change over a similar period.
Surface phenomena in capillary flow of polymer solutions.
Creators: name: Kuang, Pei Qiong.
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 1992
Subjects: subject: Engineering, Chemical.

description: Evaluations of apparent slip and surface effects characterizing polymer adsorption are reported for laminar capillary flow of dilute aqueous solutions of three homologous compounds of Polyox, denoted by WSR 301, Coagulant and FRA. Measurements were carried out using very dilute solutions in the polymer concentration range 5 to 200 ppm and very fine glass capillary tubes with diameters varying from 0.0054 to 0.047 cm. Results were obtained for glass capillary tubes coated with a silane compound (dimethyldiethoxysilane) as well as for the untreated glass tubes to provide a comparison between wall effects observed with a hydrophilic surface and a chemically modified surface. The results indicate that flow enhancement characterized by a positive effective velocity at the wall is dominant at the very low polymer concentrations and flow retardation characterized by a negative effective velocity at the wall is dominant at the higher concentrations comprising the polymer concentration range investigated. In general, it was found that the magnitude of the effective velocity at the wall increases with increasing wall shear stress and the contribution to the total flow rate becomes more significant in the tubes of smaller diameter. A transition from a positive to a negative effective velocity at the wall was observed with increasing polymer concentration. The critical concentration marking the transition was found to be higher for the silane-treated tubes than for the untreated tubes. The effective hydrodynamic thickness of the adsorbed polymer layer corresponding to zero shear was evaluated directly from the capillary flow data. The thickness in the plateau region at higher polymer concentrations was found to be greater than two times the root mean square radius of gyration of the polymer molecule for solutions of the three polymers in the untreated tubes while lower value was obtained for the same solutions in the treated tubes. A new analysis was applied to separate the contributions of polymer adsorption and slip in the evaluation of the effective velocity at the wall. In the analysis, the flow was modeled by postulating an adsorption isotherm for representation of the variation of the adsorbed layer thickness at zero shear with polymer concentration and assuming a linear dependence of the effective slip velocity on the wall shear stress. Effective hydrodynamic thicknesses of the adsorbed layers are presented as a function of the polymer concentration and wall shear stress for the three Polyox homologues investigated in the chemically treated and untreated glass tubes. The variation of the slip coefficients with polymer concentration of the solutions was also evaluated. End effect corrections based on flow measurements obtained by varying the tube lengths of the capillaries in the L/D range 750 to 2000 were applied to the data using a modification of the Bagley plot.
Modeling and Efficient Simulation of District Heating Network
Creators: name: Eimer, Matthias
name: :Unav
Publisher: name: Fraunhofer-Gesellschaft
Year: 2021
Subjects: District heating networks
Mathematical Modeling
Numerical Simulation
High order Methods
Finite Volume Methods
Partial Differential Equations

description: This thesis tackles the modeling and efficient simulation of district heating networks. The dynamical behavior of water in the pipes is described by the incompressible Euler equations. Conservation of the involved quantities determines the coupling at each junction in the network, leading to a system of partial differential algebraic equations. For that system, the unique existence of a solution is shown. Furthermore, a stability estimate for the dependence on important parameters is derived. A new local time stepping algorithm is presented that is perfectly suited for the solution of the transport problem involved. In comparison to generic high order ADER schemes its high efficiency outperforms the classical approach significantly. In order to enable computation of vary large time steps, implicit methods are investigated. A high order finite volume method is equipped with an a posteriori limiter. The superior behavior of the constructed hybrid scheme is shown in different numerical tests and applications. The obtained results build an important foundation for the upcoming optimization problems.
Étude du "Germ plasm" de l'orge cultivée Hordeum vulgare L. (Poaceae) en relation avec sa résistance à l'aphide Schizaphis graminum (Rondani) Homoptera : Aphididae.
Creators: name: Kéita, Sékou Moussa.
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 1992
Subjects: subject: Agriculture, Agronomy.

description: By means of ANOVA, Duncan's test Student's t test and linear regressions, it was demonstrated that there was no significant correlation between the quantity of gramine and the morphological characters considered (geographic origin, spike row number, spike form, cultivation season, glume length, yield, water content of fresh leaves, seed mean mass, and seed colour). By "Duncan's multiple range test" it was shown that there was a significant (F = 26,81; P 0.0001) variation in gramine content between the different genotypes (minimum = 0 & maximum = 2674). However, canonical discriminant analyses and "cluster"ing by the MODECLUS procedure failed to provide justification for grouping of varieties susceptible to aphid attack, leading to the conclusion that gramine content cannot be sufficiently closely related to morphological characters to serve as a basis for taxonomy. Finally, additional experimentation revealed that the presence of gramine alone is often not sufficient to confer protection against aphid attack, and other factors must be considered, such as anatomy or the existence of other protective constituents. Such research could lead to the development of new resistant biotypes. (Abstract shortened by UMI.)
Modellierung des thermomechanischen Materialverhaltens und der Gefügeentwicklung mikrolegierter Stähle
Creators: name: Kertsch, Lukas
name: :Unav
Publisher: name: Fraunhofer-Gesellschaft
Year: 2021
Subjects: Materialmodellierung
Kontinuumsmechanik
Thermodynamik
Mikrostruktur
Thermomechanik

description: Bei der Warmumformung und Wärmebehandlung metallischer Werkstoffe kommt es zu ausgeprägten Gefügeveränderungen durch Rekristallisation, Kornwachstum und Phasenumwandlungen. Diese bestimmen nicht nur die Eigenschaften der fertigen Halbzeuge und Bauteile, sondern sie stehen auch in enger Wechselwirkung mit dem thermomechanischen Materialverhalten. In dieser Arbeit wird ein Modell für das thermomechanische Materialverhalten und die Gefügeentwicklung metallischer Werkstoffe erarbeitet. Auf Grundlage des Müller-Liu-Verfahrens werden bewährte Modelle erweitert und in einem einheitlichen thermodynamischen Rahmen vereinigt. So werden die verschiedenen Aspekte des Werkstoffverhaltens und ihre wechselseitigen Kopplungsphänomene thermodynamisch konsistent abgebildet. Das Materialmodell wird als Simulationsprogramm für die Prozessanalyse implementiert. Es gibt das thermomechanische Verhalten und die Gefügeentwicklung eines mikrolegierten Stahls mit guter Genauigkeit wieder. Der Modellansatz kann darüber hinaus auf andere Legierungen mit ähnlichen Gefügeeigenschaften übertragen werden.
Enhancement of Speech Auditory Brainstem Responses Using Adaptive Filters
Creators: name: Anwar, Fallatah
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2012
Subjects: Adaptive Filters
Auditory Brainstem Response

description: Several adaptive filters were investigated to enhance speech auditory brainstem responses (speech ABR). The objective was to shorten the long recording time currently needed by the standard coherent averaging method to obtain acceptable performance, which has limited the clinical adoption of speech ABR. Five algorithms were implemented: Wiener Filter (WF), Steepest Descent (SD), Adaptive Noise Cancellation (ANC) based on Least-Mean-Square error (LMS) and normalized LMS error (nLMS), and a multi-adaptive cascade combination of SD and LMS. The performance of the adaptive filters was assessed on speech ABR data gathered from several subjects and compared with coherent averaging using the overall Signal-to-Noise Ratio (SNR), the local SNR around the fundamental frequency and the first formant, and Mean-Square-Error (MSE) in the time and frequency domains. The adaptive filters could reduce the time needed, by at least one order of magnitude, for obtaining comparable signal quality as that obtained with coherent averaging.
Effects of phosphorus rates, sowing date and variety on growth and yield of hyacinth bean (Lablab purpureus (L.) Sweet) in Ringim, Jigawa State, Nigeria.pdf
Creators: name: Elemi, Ekama Derrick
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 300201
subject: Agricultural hydrology
classificationCode: 300202
subject: Agricultural land management
classificationCode: 300203
subject: Agricultural land planning
classificationCode: 300204
subject: Agricultural management of nutrients

description: Field experiment was conducted during the 2019, 2020 and 2021 cropping seasons at the Jigawa State Horticultural Farm, Ringim in the semi-arid zone of Nigeria. The experiment was conducted to determine the effect of phosphorus, sowing dates and variety on the growth and yield characters of lablab. The treatments consisted of four levels of phosphorous (0, 20, 40 and 60 kg/ha), two local varieties of lablab (Dan Inusa and Dan Farankachi) and three sowing dates (1st, 15thand 29th of July). The experiment was laid out in a Randomized Complete Block Design (RCBD) replicated three times. Growth and yield characters were measured and correlation analysis was done. Results indicated that 60 Kg P/ha produced highest seed yield. Sowing on 29th of July had highest yield and Variety Dan Inusa out yielded the other variety. The results also showed that most of the growth and yield components had significant positive correlation with yield. However, crop growth rate was observed to have significant negative correlation with the crop yield. It could be recommended that most of the growth and yield parameters were good yield contributing characters. Keywords: Growth, Yield characters. Correlation
Numerical investigation of the new observation-based wind-wave source function
Creators: name: Babanin, Alexander
name: Tsagareli, Kakha
name: Young, Ian
name: Walker, David
Publisher: name: Swinburne
Year: 2024

description: Numerical simulations of the wind-wave spectrum evolution are conducted by means of new observation-based wind-input and wave-dissipation functions obtained in the Lake George field experiment. This experiment allowed simultaneous measurements of the source functions in a broad range of conditions, including extreme wind-wave circumstances. Results of the experiment revealed new physical mechanisms in the processes of spectral input/dissipation of wave energy, which are presently not accounted for in wave forecast models. These features had been parameterised as source terms in a form suitable for spectral wave models, and in the presented study were tested, calibrated and validated on the basis of such a model. In the case of the input term, which is the main subject of this paper, these are its nonlinear behaviour and its relative reduction at conditions of strong winds/steep waves. For the dissipation function, the main new features are the wave-breaking threshold and the cumulative term. Physical constraints were imposed on the source functions in terms of the known experimental dependences for the total wind-wave momentum flux and for the ratio between the total input and total dissipation. Enforcing the constraints in the course of wave-spectrum evolution allowed calibration of the free experimental parameters of the new input and dissipation functions. The approach thus allows separate calibration of the source functions, before they are employed in the evolution tests. The evolution simulations were conducted by means of the one-dimensional research WAVETIME model with an exact solution for the nonlinear term. The resulting time-limited evolution of integral, spectral and directional wave properties, based on implementation of the new physically-justified source/sink terms and constraints, is then analysed. Good agreement of the simulated evolution with known experimental dependences is demonstrated.
A Data-Driven Concept and Realization for Engineering Change Management Decision Support
Creators: name: Pan, Yuwei
name: :Unav
Publisher: name: Fraunhofer-Gesellschaft
Year: 2022
Subjects: Engineering Change Mangement
Artificial Intelligence
Automotive
Change Impact Prediction
Explainable AI

description: In today's automotive industry, quickly reacting to engineering changes and providing market-driven products within a short period remains a competence for all Original Equipment Manufacturers (OEMs). Due to the complexity of products, changes to one component can lead to unexpected chain reactions in others. Besides, from creation to the approval of a change request can take weeks or even months without apparent reasons for the delays. To coordinate and control changes, companies established Engineering Change Management (ECM) processes. ECM processes can impact all determinants of competition of products: cost, quality, and time-to-market. Without proper management of Engineering Changes (ECs), negative impacts will happen. In the scope of this dissertation, a machine-learning based ECM decision support solution is developed which includes two main functions: change impacts prediction and lead time prediction. These functions support engineers to have an overview of change consequences in the early phase of the ECM process. The solution was evaluated based on the data from an automotive company and reached good performance. Therefore it was rated as beneficial to increase the efficiency, effectiveness, and quality of the existing ECM processes.
Investigation of the Effect of Changes in Lipid Bilayer Properties on the Activity of the Bacterial Cell Division Regulator Protein MinD
Creators: name: Ayed, Saud
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2012
Subjects: Bacterial division
Min proteins
Min oscillation
MinD ATPase
membrane composition
ATP hydrolysis
MinD polymerization
Fluidity
Kinetics

description: Bacterial cell division requires formation of the cytokinetic cell division septum at the mid-cell position, a process that is determined by three Min proteins; MinC, MinD and MinE. Regulation of cell division by Min proteins occurs via a multi-step process involving interactions between various Min proteins, as well as the membrane. In this cycle, ATP-bound MinD binds to the membrane surface where it can recruit MinC to inhibit formation of the cell division septum. MinE binding to this complex displaces MinC and stimulates ATP hydrolysis, leading to the dissociation of MinD from the membrane. These interactions give rise to a dynamic pattern of Min protein localization that appears to involve a polymeric state that is designed to create a zone that is permissive to cell division at the mid-point of the cell. The interaction between MinD and the membrane is a critical aspect of this cycle, yet the role of the lipid bilayer in MinD activation, localization and polymerization is not well understood. To probe the role of membrane charge and fluidity on MinD activation and polymerization, we developed a kinetic assay of MinE-stimulated MinD ATPase activity. We found that membrane charge is essential for MinD activation and that differences in membrane fluidity give rise to changes in its activity. Moreover, a burst phase was also observed during the first few minutes of reaction, but only on the most fluid anionic lipid tested. To help determine if the observed membrane-dependent changes in MinD activity are linked to any changes in MinD polymer structure, we have begun to develop a method to identify surface exposed regions of MinD through a combination of covalent labeling and mass spectrometry. Optimization of various steps for the assay has been done, and the assay can be applied to the future characterization of MinD polymer structure. Results from this assay, in combination with those from the kinetic measurements described here, will help to improve understanding about how membrane properties modulate MinD ATPase activity, and how this can influence the Min protein oscillation that is required to ensure normal bacterial cell division.
A new approach to testing the efficacy of drinking water disinfectants
Creators: name: Grunert, Andreas
name: Frohnert, Anne
name: Selinka, Hans-Christoph
name: Szewzyk, Regine
Publisher: name: My University
Year: 2018
Subjects: Kolibakterien

description: New disinfection procedures are being developed and proposed for use in drinking-water production. Authorising their use requires an effective test strategy that can simulate conditions in practice. For this purpose, we developed a test rig working in a flow-through mode similar to the disinfection procedures in waterworks, but under tightly defined conditions, including very short contact times. To quantify the influence of DOC, temperature and pH on the efficacy of two standard disinfectants, chlorine and chlorine dioxide, simulated use tests were systematically performed. This test rig enabled quantitative comparison of the reduction of four test organisms, two viruses and two bacteria, in response to disinfection. Chlorine was substantially more effective against Enterococcus faecium than chlorine dioxide whereas the latter was more effective against the bacteriophage MS2, especially at pH values of >7.5 at which chlorine efficacies already decline. Contrary to expectation, bacteria were not generally reduced more quickly than viruses. Overall, the results confirm a high efficacy of chlorine and chlorine dioxide, validating them as standard disinfectants for assessing the efficacy of new disinfectants. Furthermore, these data demonstrate that the test rig is an appropriate tool for testing new disinfectants as well as disinfection procedures.
Deformationsverhalten des elastischen Werkzeugsystems beim Bandschleifen
Creators: name: Eiken, Michael
name: :Unav
Publisher: name: Fraunhofer-Gesellschaft
Year: 2024
Subjects: Schleiftechnologie
Bandschleifen
Deformationsverhalten
Prozessauslegung
Modellierung

description: Das Bandschleifen besitzt aufgrund seiner großen Anpassungsfähigkeit an verschiedene Werkstückformen und -gestalten ein sehr breites Anwendungsspektrum. Allerdings sorgen, trotz der weiten industriellen Verbreitung und Anwendung, fehlende wissenschaftliche Erkenntnisse über die nicht-linearen Prozesszusammenhänge infolge elastischer Werkzeugsystemdeformationen während des Schleifprozesses dafür, dass industrielles Potential ungenutzt bleibt. Die Prozessauslegung orientiert sich dabei an empirischen Zusammenhängen und erfolgt in der Regel erfahrungsbasiert. Die vorliegende Arbeit leistet einen Beitrag zum weiterführenden Verständnis und zur grundsätzlichen modellbasierten Auslegung von Bandschleifprozessen, wodurch zukünftig vor allem die effiziente und ressourcenschonende Ausnutzung des Schleifbands gewährleistet werden kann. Ferner erlaubt der modulare Grey-Box-Ansatz die Erweiterung des bestehenden Prozessmodells durch empirische Erkenntnisse zu anderen Werkstoffen und Werkzeugsystemen nach dem in dieser Arbeit vorgestellten Vorgehen.
Scientific data of resurrecting the dead is engineering problem and not impossible 2024.pdf
Creators: name: mosinyan, Isaac
Publisher: name: figshare
Year: 2024
Subjects: classificationCode: 510304
subject: Thermodynamics and statistical physics
classificationCode: 510103
subject: Cosmology and extragalactic astronomy
classificationCode: 510703
subject: Particle physics
classificationCode: 460299
subject: Artificial intelligence not elsewhere classified
classificationCode: 460201
subject: Artificial life and complex adaptive systems
classificationCode: 510201
subject: Atomic and molecular physics
classificationCode: 510501
subject: Biological physics
classificationCode: 510104
subject: Galactic astronomy

description: Groundbreaking interpretation of entropy shows reversal of entropy in cosmic scales is possible. Resurrection of the dead?, it should be impossible even in physics right?. Well, it was a shock to see that it was not impossible due to largerly overlooked interpretation of entropy. In recent years theoretical and empirical developments have pushed the boundaries of what we understand about entropy, the arrow of time, and the possibility of reversing death through a concept known as the "anti-entropical universe." There is a common misconception about entropy is that it is inherently tied to disorder and chaos when we understand the true nature of entropy, which it makes it a already proven explanation of how resurrecting the dead is possible which was overlooked. Back to the engineering problem, the article title which initially appears speculative, is deeply rooted in fundamental physics and emerging experimental data either from laws of physics that can act as cosmic lab or from literal recent lab results, practically a very strong hypothesis due to large body of already existing proven data. This article explores the logical and empirical pathways that indicate the possibility of an anti-entropical universe, which could challenge the traditional view of entropy and death itself, elevating this idea to the status of a scientific theory. Last reminder, a universe that is closed system will result to inevitable cosmic recycle either if it is chaotic cosmic recycle (i am not talking about big bangs necessarily because we talk about here for closed systems) or it could allow different forms cosmic pattern recycles.. like ordered cosmic recycles with maximised entropy. Anti-entropical systems, the more energy they save the more order they gain and that is a escape velocity of order patterns when we compare them with cosmic timescales of chaos increase compared to our achievements. It means simply functions of order show it might become the next candidates of a cosmic recycle since the anti-entropical laws clearly show we act as unlocking pattern systems using math.
The police force : gender, race, and use-of-force training
Creators: name: Simon, Samantha Jones
name: 0000-0002-4317-7792
Publisher: name: The University of Texas at Austin
Year: 2020
Subjects: Police violence
Police brutality
Gender
Racist violence
Ethnicity
Police hiring
Police training
Police cadets
Law enforcement practices
Police interviews
Use of force
Police departments
Police academies

description: Dozens of high-profile cases of police violence against Black people have incited public outrage and organizing. In response to this mounting pressure, police departments have implemented new practices and policies, including diversity initiatives in hiring, de-escalation training in the academy, and body cameras on officers. Despite these efforts, however, the police continue to use force disproportionately and excessively against Black people. In this dissertation, I provide evidence of the organizational practices of law enforcement that lead to racist use of force. I turn the attention away from explanations of police violence that point to officers’ individual racial biases, the purported necessity of using force in high-crime areas, or inadequate de-escalation training, to instead show how police hiring and training practices contribute to racist violence. I draw on one year of ethnographic field work at four police departments and 40 in-depth interviews with cadets and officers to answer the following questions: (1) How do police departments decide who to hire? (2) How are police cadets taught to think about their relationship with the public? (3) How are police cadets taught to use force? In answering these questions, I present three primary findings. First, I argue that the way in which police departments conceptualize the ideal candidate, and the hiring procedures and practices organized around this discourse, contribute to patterns of racist violence. Second, I show that at the academy, cadets are taught to be warriors, and that their enemies are Black men. Lastly, I argue that the academy conditions cadets’ bodies, through repetition and institutional disciplining, to engage in violence. In this dissertation, I focus on hiring and training to provide an organizational explanation of racist trends in police violence
Beyond Transition: Understanding Workplace Integration of Internationally Educated Nurses - A Qualitative Case Study
Creators: name: Ramji, Zubeida
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2016
Subjects: internationally educated nurses
workplace integration
two-way integration
organizational influence
critical social theory
definitiona
conceptual framework

description: Internationally Educated Nurses (IENs) have been proposed as one solution to dealing with the nursing shortage in Canada. In addition to helping sustain the profession, IENs are reflective of the diverse patient populations in Canada. Investments will ensure healthy workplaces for and retention of IENs. There has been a growing interest about IENs’ experiences with migration and navigating through the regulatory process, but research on their post-transition experience is lacking. Workplace integration for IENs is not well understood and the role of the employer has received limited focus. Guided by critical social theory, an instrumental qualitative case study approach was used to examine a single organization, St. Michael’s Hospital, Toronto, with a history of supporting IENs. A purposeful sample of twenty-eight participants included diverse IENs who were post-transition, and stakeholders from various vantage points. Four forms of data collection were used: semi-structured interviews; socio-demographic survey; review of documents and focus groups. Thematic analysis was carried out to form a within subcase analysis first, followed by an across subcase analysis. The major themes are: (a) when “integrated”, an IEN is (i) being a “Canadian nurse with international experience”; (ii) progressing on the leadership journey; and (iii) persevering in overcoming challenges; (b) organizational factors that influence workplace integration of IEN are (i) workforce diversity; (ii) leadership commitment to equity; (iii) policies promoting equity principles; (iv) engagement with the broader community; and (v) avoiding common pitfalls. This research offers a definition and conceptual framework where workplace integration of IENs is a “two-way” process within an inclusive and valuing context, producing changes both at the IEN as well as organizational levels.
Applications of Time Series Forecasting Models, Decomposition Methods, Non-parametric Regression Methods, and Artificial Neural Networks
Creators: name: Shaqiri, Fatlinda
name: :Unav
Publisher: name: Fraunhofer-Gesellschaft
Year: 2024
Subjects: Time Series Forecasting Models
Regression
Artificial Neural Networks
Decomposition Methods
Non-parametric Regression Methods

description: This thesis offers a thorough review of time series forecasting models, starting with simple forecasting methods such as linear models and ending up combining this method with dynamic models to represent interdependencies of the time series dynamics. Decomposition methods such as those from X-11 method to Seasonal and Trend decomposition using Loess (STL) method are applied to increase the prediction accuracy. As a new contribution to the literature, Artificial Neural Networks are applied to increase the chance to capture different patterns in the data and improve the forecast performance. The main parts of this thesis include the practical application of the time series forecasting models on the health insurance sector and electricity consumption, as well as on simulated data sets where different model adjustments are compared and practical recommendations regarding model choice and calibration derived.
Nano- and macro-scale characterisation of the mechanical properties of bovine bone
Creators: name: Wang, X. J.
name: Li, Y. C.
name: Hodgson, P. D.
name: Wen, Cuie
Publisher: name: Swinburne
Year: 2024

description: In the present study, nano- and macro-scale characterisations on the mechanical properties of bovine cortical bones have been performed by using nanoindentation and conventional compressive tests. Nanoindentation results showed that the elastic modulus for the osteons and the interstitial lamellae in the longitude direction were 24.7 ± 2.5 GPa and 30.1 ± 2.4 GPa. As it’s difficult to distinguish osteons from interstitial lamellae in the transverse direction, the average elastic modulus for cortical bovine bone in the transverse direction was 19.8 ± 1.6 GPa. Significant differences were found in the modulus values between different microstructures of bone tissue and in different testing direction. It was found that the elastic modulus of bone bovine material in nano-level was higher than that in macro-level. The elastic modulus and ultimate stress of large bone samples were 12.5 ± 1.9 GPa and 195 ± 19 MPa respectively from the compression test.
Can we measure equitable access at the intersection of social and natural systems? : a look at the spatial and social distribution of urban parks
Creators: name: Ibarra, Victoria Sanchez
name: 0000-0002-4765-8040
Publisher: name: The University of Texas at Austin
Year: 2020
Subjects: Equity mapping
Urban parks

description: Parks are embedded in our urban life, providing ecosystem services, health benefits, and social capital. However, not every community has access to urban parks, and many researchers and activists have questioned whether access is equitable across communities. The methods themselves, which determine equitable access, are inherently inaccessible because they utilize proprietary software which cannot be easily replicated. This study seeks to develop a framework to assess equitable access using open source spatial technologies, specifically Python and QGIS. This work addresses the following questions: 1) How is equitable access currently defined, and is this definition adequate at identifying those without equitable access?; 2) Are parks equitably accessible to vulnerable communities (e.g., children, the elderly, women, low-income households, ethnic minorities)?; and 3) Based on the definition of equitable access used in this study, which subsets of the population are not receiving access? Using Austin, Texas as a case study, it was found that less than half of Austin’s population lives within a quarter mile of a park (45.2%). Consistent with literature, in this study racial minorities (specifically, Hispanic and Latinx) and low-income communities had the greatest access to parks with 47% and 48.5% respectively. This study also determined that Austin’s north-central and south-central regions are most in need of parks. As such, park officials should focus on increasing access to those areas. The open-access framework created will provide practitioners with a quick method to identify demographics that are being served. This enables city planners and officials to understand demographic trends to better improve equitable access across their city. The open-access nature of the framework lends itself to the application of a variety of equity mapping and spatial injustice studies, such as the identification of transit and food deserts in metropolitan areas.
Identification of the Irreversible Redox Behavior of Highly Fluorescent Benzothiadiazoles
Creators: name: Rietsch, Philipp
name: Sobottka, Sebastian
name: Hoffmann, Katrin
name: Hildebrandt, Pascal
name: Sarkar, Biprajit
name: Resch‐Genger, Ute
name: Eigler, Siegfried
Publisher: name: Freie Universität Berlin
Year: 2020
Subjects: subject: Irreversible Redox Behavior
subject: Highly Fluorescent Benzothiadiazoles
subject: 500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften

description: Redox switches are applied in various fields of research, including molecular lifts, electronic devices and sensors. Switching the absorbance between UV and Vis/NIR by redox processes is of interest for applications in light harvesting or biomedicine. Here, we present a series of push‐pull benzothiadiazole derivatives with high fluorescence quantum yields in solution and in the crystalline solid state. Spectroelectrochemical analysis reveals the switching of UV‐absorption in the neutral state to Vis/NIR absorption in the reduced state. We identify the partial irreversibility of the switching process, which appears to be reversible on the cyclic voltammetry timescale.
Text A: Teasing Out the Influences on Early Gardnerian Witchcraft as Evidenced in the Personal Writings of Gerald Brosseau Gardner
Creators: name: Crandall, Lisa
Publisher: name: Université d'Ottawa / University of Ottawa
Year: 2013
Subjects: Text A
Gardner
Gerald Gardner
Gerald Brosseau Gardner
Wicca
Gardnerian Wicca
Witchcraft
Gardnerian Witchcraft
Pagan
Neo-Pagan
Valiente
Magic
Book of Shadows
grimoire
Witch

description: This thesis is an intensive, multi-layered analysis of an unpublished, English language, handwritten, mid-20th century manuscript. Originally undated, untitled and unsigned, it has now been positively identified as “Text A”, a Wiccan proto-Book of Shadows compiled by Gerald Brosseau Gardner (1884-1964) in the last half of the 1940’s. Different methodologies were applied to the document: transcription using Leiden conventions, handwriting analysis to identify the author, archival research to uncover photographs of the manuscript in use, historical and bibliographical research to situate the manuscript and its author, and finally, an in-depth and exhaustive source analysis to uncover literary and documentary influences on the text. Subsequently, the manuscript was identified as handwritten by Gerald Gardner, from 1940 to 1949, and contains almost no original material other than a handful of pages for a speech or oral presentation. The rest of the document is comprised of extracts from published sources available to Gardner. These include books on Free Masonry, Templars, British Folklore, Kabbalah, Magic – ancient and ceremonial, and books by Aleister Crowley. The document also includes ritual passages and ceremonies, most of which also appear in Gardner’s published novel, High Magic’s Aid. Two theme-lines, “Magic – ancient and ceremonial” and “the writings of Aleiser Crowley”, comprising almost 40% of the total page count, were chosen for thorough analysis. Based on the information revealed by the various methodologies applied to this document, one can assert that Gardner’s claims to have been initiated into an ancient indigenous tradition, Wicca, and to be making available its long secret rituals are not supported by this document.
Fracturing in carbonate sediments above a salt diapir (Jebel Madar, Oman)
Creators: name: Stehle, Manuela Christina
Publisher: name: Imperial College London
Year: 2017

description: Salt-cored domal structures in the subsurface represent common reservoir settings. Understanding the generations and properties of the fracture network above such structures is therefore important. This outcrop-based study investigates fractures in the deformed carbonate layers exposed above a salt dome at Jebel Madar, Oman. Methods used to study the fractures and their infillings include fracture analysis, petrography and stable isotope geochemistry. Regionally occurring NNE/NE-SSW/SW and NW-SE trending fractures constitute important fracture sets across Jebel Madar. In addition, it was observed that the doming process led to the development of local fractures that overprint the regional trends. A study of the textures and composition of the fracture infilling material indicates that a dominantly advective mode of fluid transport occurred in the NNE/NE-SSW/SW trending veins, which developed due to repeated fracturing and re-cementation. These veins are associated with phases of doming and related pulses of high volumes of fluids during times when the maximum horizontal stress was oriented NE-SW. In contrast, a more diffusive mode of fluid transport is thought to have occurred in the NW-SE trending fractures, which developed during times when no doming was occurring. Although the diapir seems to be the main drive for fluid circulation and the precipitation of most diagenetic products occurred during periods of doming, vein infilling also occurred, to a lesser extent, during periods when doming was absent. The frequent occurrence of normal faults, extensional opening fractures and implosion breccia suggests that the layers above the diapir were highly extended during the salt emplacement. In addition, some of the extension was found to be accommodated by the development of shear movement (down-dip slip) on original mode I fractures. Their similar appearance on seismic sections to classic normal faults could lead to a misinterpretation of their fluid flow properties.
Comparing the global and molecular rheology of fluids, in situ, under high pressures
Creators: name: Dench, Jon
Publisher: name: Imperial College London
Year: 2018

description: This abstract is based on the authors previously published work: ‘In situ viscosity measurement of confined liquids’ and ‘Quantitative Viscosity Mapping Using Fluorescence Lifetime Measurements’ and work submitted for publication: ‘Comparing the molecular and global rheology of a fluid under high pressures’. The viscosity of pressure-sensitive liquids governs crucial physical phenomena. While data on lowpressure viscosity is easy to obtain using conventional rheometers, obtaining high-pressure rheology presents a significant challenge. This is particularly important for fluids operating in the elastohydrodynamic lubrication regime under high shear stresses where fluids are likely to experience shear thinning. Two new in situ viscosity measurement techniques have been developed and applied to a point contact with submicron film thickness. They involve the quantification of fluorescence lifetime for a viscosity-sensitive fluorophore or the fluorescence anisotropy of a conventional fluorophore. Spatial heterogeneity in viscosity caused by variations in pressure is measured in both Newtonian and nonNewtonian fluids. Fluorescence lifetime measurements were performed at pressures up to 1.2 GPa and shear rates up to 105 s-1. Fluorescence anisotropy measured viscosities quantitatively up to 6 Pa.s under Newtonian conditions. This work combines friction measurements, high-pressure rheometry and local molecular viscosity measurements and compares against well-known rheological models. Together viscosities ranging five orders of magnitude, at pressures up to 720 MPa, were examined. It is shown that friction measurements can be used to determine viscosity if adjustment is made to take into consideration the effect of pressure distribution, shear thinning and heating. Single exponential models cannot predict viscosity over the complete viscosity range. The initial compressibility and thus rapid decrease in pressure-viscosity coefficient limits the maximum viscosity under which the Barus equation can be applied. After the initial reduction in free volume, the pressure-viscosity response can be represented well by a single exponential relationship. The Roelands equation was shown to predict the results well up to 720 MPa and 630 Pa.s. The Hybrid model fits well but requires a large range of data making it suitable for interpolation but not extrapolation.
The health impacts of public transport use
Creators: name: Patterson, Richard Alexander
Publisher: name: Imperial College London
Year: 2019

description: Introduction Public transport use is common and often involves short walks to and from public transport stops. Population impacts of physical activity accumulated as part of public transport journeys are potentially substantial but remain understudied compared with other transport modes. This thesis aims to examine the potential health effects of public transport use. Methods (1) A systematic review of the cardio-metabolic health effects of public transport. (2) Analyses of nationally representative data to examine predictors of public transport use and related physical activity. (3) Examine the association between the English free older person’s bus pass and bus use and active travel levels, and establish whether these impacts differ across ethnic groups. (4) Analyses of census data to identify associations of public transport commuting with cancer and mortality. Results The systematic review found 10 studies and concluded that public transport was associated with reduced adiposity, with little research available on other outcomes. Public transport use in England is higher among: women, those of minority ethnicity and the socio-economically disadvantaged. Public transport users in England accumulated an average of 21 minutes a day of physical activity in the course of public transport journeys. The free bus pass had high uptake and was associated with higher bus use and active travel and these effects may be greater among ethnic minority groups. Public transport commuting in England and Wales was associated with reduced cancer incidence, with larger associations seen in rail commuters than bus commuters. Discussion Public transport use in England is common and is associated with reduced adiposity, higher physical activity and lower incidence of cancer. These findings suggest that increasing public transport use can improve population health through increased physical activity.
Dynamics of ocean jets over topography
Creators: name: Khatri, Hemant
Publisher: name: Imperial College London
Year: 2019

description: Alternating jets seen in the oceans are often transient in nature as they possess spatio-temporal variability. Ocean bathymetry is believed to be one of the primary causes for the jet variability. In this thesis, the dynamics of alternating jets and mesoscale eddies is studied in the presence of a zonally sloped topography in a baroclinic quasi-geostrophic model, which is forced with an imposed vertical velocity shear. It is observed that the jets tilt from the zonal direction and drift meridionally. The jets tend to align with the barotropic potential vorticity isolines and drift speeds match well with the phase speeds of linear Rossby waves. Thus, the linear dynamics controls the jet drift. Also, the tilted jets are coupled to the imposed shear and are able to gain energy directly from the imposed shear. On the other hand, eddies remove energy from the jets; hence, eddies act against the jets. The results are further confirmed by analysing the mean-flow and eddy energy budgets. These results are limited to continuously forced dissipative systems. In weak dissipation regimes, in addition to the tilted jets, purely zonal large-scale modes are observed. The zonal modes gain energy from eddies and the tilted jets through nonlinear interactions. The results suggest that alternating jet patterns in the oceans can also form due to interactions among eddies and various large-scale modes. The mechanism is different from the classical arguments, in which only mesoscale eddies force the jets. Also, a direct energy transfer from the imposed shear to jets is not possible in the model of stationary zonally symmetric jets. Further, it is found that energy transfer to the jets via Reynolds stress work is higher in the layer having a positive meridional gradient in the background potential vorticity. This is qualitatively explained by simple reasoning based on Rossby wave group velocity.
The atmospheric heating patterns: a new heat transport perspective
Creators: name: Liang, Minyi
Publisher: name: Imperial College London
Year: 2019

description: The standard definition of poleward heat transport was found to lead to surprisingly large fluctuations (in excess of $10^{15}$W = 1PW) on timescales shorter than a few years. We have argued in this thesis the standard definition masks more meaningful climate signals present in the heat transport variability, and a new definition is proposed to isolate the latter. Utilising the new definition of heat transport, large/weak heat transport events are identified. The atmospheric heating patterns by the mean flow and eddies under these enhanced heat transport events are also discussed. It is found that for every 1PW increase in heat transport across $45^\circ$ latitude, a surface heating and cooling dipole at the rate of about 0.3 K/day is observed. This is largely attributed to stationary (transient) eddies in the NH (SH). The same dipole structure is noticeable in the upper troposphere but tilted towards the pole when analysing the heating patterns by eddies (but is partially compensated by the mean flow). This tilted dipole might be linked to poleward energy propagation. For the sub-tropics, when the atmosphere carries more heat across $10^\circ $ latitude, a vertically coherent heating/cooling, extending from the surface to the upper troposphere, is observed, with values being about $\pm$ 0.5K/day. This heating pattern is closely linked to the strengthening of the Hadley circulation. Using the standard definition of heat transport, similar heating patterns are also found, although the magnitude is much smaller. This further confirms our hypothesis that the new definition may shed further light on the intuitive link between energy transport and climate variability. The above analysis is carried out under the Eulerian mean framework. Next, we analyse the cancellation effect between the mean flow and eddies using the three most popular frameworks under pressure coordinates: the Eulerian mean, the conventional transformed Eulerian mean, and the modified transformed Eulerian mean. It is found that the choice of framework largely depends on the domain one is interested in, and there is no one framework that is more favourable than the others. We further conclude that Eulerian mean framework is adequate for the analysis of the heating patterns under enhanced heat transport events as discussed in this thesis.