Dissertations / Theses: 'Penetration into a pool'

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Chen, Yu-Ting. "REAL-TIME IMAGE PATTERN SENSOR FOR WELD POOL PENETRATION THROUGH REFLECTION IN GTAW." UKnowledge, 2018. https://uknowledge.uky.edu/ece_etds/130.

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In gas tungsten arc welding (GTAW), weld pool surface contains crucial information for welding development. In this research, simulate skilled welders to control the welding process and determine the penetration stages based on the weld pool reaction. This study focuses on solving the uncertainty of the liquid weld pool in joint bases. The weld pool penetration process is highly depending on how the weld pool surface shape. To observe the weld pool, reflect the weld pool surface by the laser and image on the shield glass. The experiments show that the penetration can’t be determine by the reflecting grayness due to the variability of base metal. To control the joint bases diversity, fed a tip of the wire after the arc is established. Crate the new pattern of the weld pool penetration. Experiments verified the feasibility of this method.

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Janssen, Arthur. "Modeling the market penetration of passenger cars with new drive-train technologies." [Zürich], 2005. http://e-collection.ethbib.ethz.ch/ecol-pool/diss/abstracts/p15855.pdf.

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Woodward, Neil J. "Pool oscillations and cast variations : penetration control for orbital tig welding of austenitic stainless steel tubing." Thesis, Cranfield University, 1997. http://dspace.lib.cranfield.ac.uk/handle/1826/4512.

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Pool oscillations in tungsten inert gas welding pools have been used in a closed-loop control system for orbital welding of ultra high purity tubing, determining a target level of penetration by altering the welding current in real-time. The technique is ideally suited to this application since it is does not contravene the cleanliness requirements for the inner bore and can be implemented outside the small orbital heads that are commonly used. The results presented in this thesis show how clear pool oscillation signals in extremely small molten pools can be monitored by optimising the welding conditions and signal processing of the arc voltage signal. As an indicator of the likely variation in cast behaviour present particularly in austenitic stainless steels, a 'time-to-penetrate' characterisation was made of the materials, using the time of the transition from the Mode 1 to the Mode 3 oscillation behaviour as the measured variable. By applying the test across a range of welding currents, significant insight was obtained into the cast and associated penetration behaviour. Late transitions indicated casts that exhibited significantly different responses to the more usually applied welding procedures, especially at the lower levels of welding current (highlighting their potentially more problematic penetration behaviour). It was shown that the established theoretical models were difficult to apply with certainty to moving weld pools, and consequently a fuzzy logic model was used in the control strategy. The closed-loop system comprised a user-interface PC, a control rack and commercial welding power source - control signals were applied every 2 to 3 Hz. Mode 3 pool oscillations were found to offer a more than satisfactory sensitivity to the inner bead width created for the various casts of 1.65 mm wall thickness materials studied.

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Yoo, Choong Don. "Effects of weld pool conditions on pool oscillation /." The Ohio State University, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=osu148768624382255.

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Nilsson, Linette. "Swimming Pool." Thesis, Konstfack, Textil, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:konstfack:diva-5827.

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My project started with two words: Swimming Pool. They came to me through a song, Banshee Beat by Animal Collective (2005). To me, their music is mystical, abstract, unpredictable and also metaphorical. So I started to think about if a swimming pool could be something more than just an open container filled with water. After some thinking I came to the conclusion that it could be a metaphor for something calm, quiet and dreamy. However, I’m not sure but my aim is not to get to a specific answer through this project. I’ll turn the metaphor into a textile work that portrays what you see when you’re standing at the edge of the swimming pool; a distorted picture of a grid, the bottom of the pool. I’ll be working with dyeing, patchwork and quilting. The textile craft is important in this project because of how relaxed and calm I get by doing things with my hands. The questions I’m asking myself are how I can express the metaphor through my work? What if my interpretation is too wide? Is it possible for me to create a tactile and calm feeling without the physical touch?

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Gao, Hongjiang. "Hypothesis testing based on pool screening with unequal pool sizes." Thesis, Birmingham, Ala. : University of Alabama at Birmingham, 2010. https://www.mhsl.uab.edu/dt/2010p/gao.pdf.

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Stemple, Carrie M. "Perceptions of calf pool participants toward West Virginia calf pool organizations." Morgantown, W. Va. : [West Virginia University Libraries], 2007. https://eidr.wvu.edu/etd/documentdata.eTD?documentid=5128.

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Thesis (M.S.)--West Virginia University, 2007.
Title from document title page. Document formatted into pages; contains vi, 102 p. : col. ill. Vita. Includes abstract. Includes bibliographical references (p. 46-48).

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Delgado, T. Cristina, M. Ivis Vanessa Delgado, G. José Antonio Montalvo, and José Miguel Quiróz. "Chivis pub, pool lounge." Tesis, Universidad de Chile, 2005. http://www.repositorio.uchile.cl/handle/2250/114213.

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Tesis para optar al grado de Magíster en Administración(MBA)
No disponible a texto completo
En la actualidad el concepto de vida nocturna esta teniendo cada vez más auge en la vida de los Santiaguinos, estos buscan diversas formas de distracción ya sea en Pubs, Restaurantes u otros. Este crecimiento se ve reflejado en el sostenido aumento de las ventas de esta industria. Por ejemplo, en el primer trimestre del 2004 con relación a igual periodo del año anterior, hubo un crecimiento de un 1.3%. (Diario El Mercurio 04.10.04 ) Conjugando esta situación, con los cambios en los gustos de los consumidores, que indican que, más de un 60% de las personas, van a divertirse a Pubs y que salen en promedio dos veces a la semana, se fundamenta nuestra idea de abrir “CHIVIS”, un Pub, que ofrecerá gratos ambientes, para disfrutar y divertirse en un mismo lugar. Ambientes para degustar una comida agradable, para disfrutar de juegos como mesas de billar profesionales con asientos y muebles confortables para que los que no estén jugando puedan acompañar y disfrutar a su vez. Será la parada perfecta, para después de la oficina, almorzar, comer algo o tomar un trago, tal vez una pequeña reunión social, de negocios o para disfrutar simplemente de juegos y diversión. Todo esto es reforzado por nuestro objetivo principal, una atención personalizada, una orientación hacia el cliente “Un servicio de excelencia”. Un gran número de personas, busca un grato ambiente al momento de elegir donde ira a divertirse, igualmente otro importante numero de personas, una excelente atención al cliente, de la misma forma hay quienes prefieren un lugar con diversas posibilidades de entretención, Chivis ofrecerá esto y más. Nos enfocaremos en ejecutivos y profesionales del segmento ABC1 y C2, principalmente de las Comunas de Las Condes y Providencia los cuales cuentan con los ingresos necesarios para poder optar por opciones de entretención. Llegaremos a ellos por medio de volantes entregados en sus oficinas y en las áreas colindantes de Chivis, así como anuncios en las emisoras Universo, Tiempo y Duna. El modelo de negocio se sustenta en obtener beneficios económicos que vendrán de la venta de bebidas y comidas, las cuales estarán soportadas por el atractivo del local. Nuestra estrategia es mantener un flujo regular de nuevos clientes, los que después de probar y disfrutar de nuestro estilo Chivis, se convertirán en clientes a largo plazo, posicionando la marca de nuestro Pub. Con una inversión de M$140.885.330, de los cuales el 67% del total, equivalente a M$93.923.553, serán aportados por los socios fundadores, y el 33% restante, correspondiente a M$46.961.777, proveniente del aporte adicional de un inversionista externo. Este proyecto presenta un VAN de M$ 60.560.163, otorgándole al inversionista externo una rentabilidad sobre su inversión al primer año del 17%, y del 157% para el término de los 5 primeros años. Estamos seguros de poseer el enlace perfecto entre los atributos y el estilo “Chivis”, con un equipo que posee experiencia en este rubro y que cuenta con los conocimientos de marketing, finanzas y gestión de servicios, que nos permitirá lograr ventajas competitivas para posicionar nuestra marca y convertirla en la primera opción para los consumidores.

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Sapountzakis, Dimitrios. "Weld penetration control system." Thesis, University of Liverpool, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428243.

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Sheiretov, Yanko Konstantinov. "Deep penetration magnetoquasistatic sensors." Thesis, Massachusetts Institute of Technology, 2001. http://hdl.handle.net/1721.1/16772.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.
Includes bibliographical references (p. 193-198).
This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
This research effort extends the capabilities of existing model-based spatially periodic quasistatic-field sensors. The research developed three significant improvements in the field of nondestructive evaluation. The impact of each is detailed below: 1. The design of a distributed current drive magneto resistive magnetometer that matches the model response sufficiently to perform air calibration and absolute property measurement. Replacing the secondary winding with a magnetoresistive sensor allows the magnetometer to be operated at frequencies much lower than ordinarily possible, including static (DC) operation, which enables deep penetration defect imaging. Low frequencies are needed for deep probing of metals, where the depth of penetration is otherwise limited by the skin depth due to the shielding effect of induced eddy currents. The capability to perform such imaging without dependence on calibration standards has both substantial cost, ease of use, and technological benefits. The absolute property measurement capability is important because it provides a robust comparison for manufacturing quality control and monitoring of aging processes. Air calibration also alleviates the dependence on calibration standards that can be difficult to maintain. 2. The development and validation of cylindrical geometry models for inductive and capacitive sensors. The development of cylindrical geometry models enable the design of families of circularly symmetric magnetometers and dielectrometers with the "model-based" methodology, which requires close agreement between actual sensor response and simulated response. These kinds of sensors are needed in applications where the components being tested have circular symmetry, e.g. cracks near fasteners, or if it is important to measure the spatial average of an anisotropic property. 3. The development of accurate and efficient two-dimensional inverse interpolation and grid look-up techniques to determine electromagnetic and geometric properties. The ability to perform accurate and efficient grid interpolation is important for all sensors that follow the model-based principle, but it is particularly important for the complex shaped grids used with the magnetometers and dielectrometers in this thesis. A prototype sensor that incorporates all new features, i.e. a circularly symmetric magnetometer with a distributed current drive that uses a magnetoresistive secondary element, was designed, built, and tested. The primary winding is designed to have no net dipole moment, which improves repeatability by reducing the influence of distant objects. It can also support operation at two distinct effective spatial wavelengths. A circuit is designed that places the magnetoresistive sensor in a feedback configuration with a secondary winding to provide the necessary biasing and to ensure a linear transfer characteristic. Efficient FFT-based methods are developed to model magnetometers with a distributed current drive for both Cartesian and cylindrical geometry sensors. Results from measurements with a prototype circular dielectrometer that agree with the model-based analysis are also presented. In addition to the main contributions described so far, this work also includes other related enhancements to the time and space periodic-field sensor models, such as incorporating motion in the models to account for moving media effects. This development is important in low frequency scanning applications. Some improvements of the existing semi-analytical collocation point models for the standard Cartesian magnetometers and dielectrometers are also presented.
by Yanko Sheiretov.
Ph.D.

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Hattingh, Keaton Jade. "Geomorphological controls on pool formation and pool persistence in non-perennial river systems." University of the Western Cape, 2020. http://hdl.handle.net/11394/7739.

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>Magister Scientiae - MSc
Globally climate variability and anthropogenic effects are causing more perennial rivers to become non-perennial rivers. Non-perennial rivers are distinguished by their isolated pools which serve as refugia for aquatic organisms, water birds, and riparian vegetation. The literature on non-perennial rivers demonstrates that pools are poorly understood in terms of their location, nature, and geomorphic persistence. Therefore, this study examines the relationships between the spatial distribution, morphology, and substrate characteristics of pools in reaches of the Prins and Touws rivers in the Klein Karoo. A greater understanding of pools will facilitate better management, monitoring, and restoration strategies for pool ecology since the geomorphology of pools provides a key part of the ecological template. Worldview-2 satellite imagery (2017) and orthorectified aerial photography (2014, 2013, and 1944) were used to assess the effects of major flooding events on pools over time. A DGPS (Differential Global Positioning System) was used to survey the pool widths, lengths, depths, and valley widths, cross-sections, and longitudinal profiles of the river. Sediment samples and Wolman pebble counts were used to assess the grain size and organic matter content of each pool in the study area. Detailed descriptions of the characteristics of each pool in terms of position in the channel, valley form, and obstruction presence and type were also assessed. Results indicate that most of the large pools occur at bedrock outcrops of the valley margins, and smaller pools are associated with Vachellia karroo debris bar features. Larger and highly persistent pools are associated with valley confinement and smaller less persistent, scour pools occur mid-channel where the valley expands. Analysis of the results shows that the valley width is the dominant control on these forced pools. The type of obstruction also plays a role in the formation of the pool as large woody debris results in smaller pools whereas, bedrock outcrops result in larger sized pools. A significant relationship was found between the grain size and organic matter content of pools. Aerial photography of the spatial distribution of the pools revealed that before a major flood, the pools were small and patchy, whereas afterward, they were larger and more elongated. It is suggested that at the bedrock outcrops, major scouring and eddy processes drive the formation of larger pools during large flood events, whereas pool dissection by sediment deposits prevails during intervening intermediate to low flow periods. The results are discussed in terms of the geomorphic controls (valley width, pool dimensions, morphology, substrate, and obstruction characteristics) on the formation and maintenance of pools in dryland settings. A conceptual model is proposed to explain the geomorphic changes of the pools in the four geomorphological zones of non-perennial rivers.

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Gatin, Laureen. "Restructuring the Saskatchewan Wheat Pool." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ39140.pdf.

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Peters, Colette. "Learning pool, a narrative inquiry." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape8/PQDD_0024/MQ42189.pdf.

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Huang, Wesley H. "A simple robot pool player." Thesis, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/12943.

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Sussitz, Hermann. "Pool Sharing in Humanitarian Logistics." Institut für Transportwirtschaft und Logistik, WU Vienna University of Economics and Business, 2010. http://epub.wu.ac.at/2995/1/Sussitz.pdf.

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Abukar, Hared, and Saati Firas Al. "Weda pool cleaner Concept P100." Thesis, KTH, Maskinkonstruktion (Inst.), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-201609.

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Syftet med detta examensarbete var att ta fram en ny drivlina för Wedas nuvarande robot poolrengörare W50. I nuläget är pumpen integrerad i drivlinan som består endast av en motor som driver både hjul och pump. Detta orsakar ett kritiskt problem som påverkar städning vid lutningar i poolen då roboten glider ner för lutningen. För att få en bättre insikt i hur produkten fungerar gjordes studiebesök till Weda. Projektgruppendokumenterade och observerade hur den nuvarande modellen och dess komponenter är monterade. Intervjuer utfördes med vaktmästare och fastighetsskötare inom olika kommunala bad och hotellpooler för att få en djupare förståelse för hur dessa robot poolrengörare används och vilka förbättringsområden som finns. Faktainsamlingen användes som grund för att ta fram förslag för nya och alternativa komponenter till det nya konceptet. De olika lösningarna blev sedan utvärderade med hjälp en beslutsmatris för att kunna bestämma vilka komponenter som skulle ingå i det slutgiltiga konceptet. Arbetet har utförts i nära samarbete med Adigo Drives, som bistått med sin expertis gällande motorer och drivlinor. Resultatet utmynnade i ett slutgiltigt koncept med en ny drivlina och en lägre vikt än den befintliga roboten.
The purpose of this study was to develop a new drivetrain for Wedas current robot pool cleaner W50. Currently, the pump is integrated in the drivetrain which contains only one motor running both wheels and pump. This causes a critical problem affecting cleaning when encountering inclinations in the pool, the robot slides down the slope. To get a better understanding of how the product works, the project group made study visits to Weda. The group documented and observed how the current model and its components are mounted. Interviews were conducted with caretakers and janitors at various municipal swimming pools and hotel pools to get a deeper understanding of how these robot pool cleaners are used and what areas for improvement that exists. The research was used as a foundation for suggestions of new and alternative components for the new concept. The different solutions were then evaluated using a decision matrix to determine which components should be included in the final concept. The work has been carried out in close cooperation with Adigo Drives, which assisted the group with their expertise regarding motors and powertrains. The results culminated in a final concept with a new powertrain and a lower weight than the existing robot.

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Bullock, Gillian. "Disinfection of swimming pool water." Thesis, Cranfield University, 2003. http://dspace.lib.cranfield.ac.uk/handle/1826/108.

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Results from this study, which has investigated the impact of the treatment technologies of chlorination, ozonation and UV irradiation on pool water quality are reported. The aim of the study was to evaluate the effect of these technologies in an unbiased way using a unique protocol, and to calculate a mass balance across the pool system. Data refer to a protocol based on operation of a 2.2m (cubed) capacity pilot swimming pool, which allows the comparison of technologies applied with reference to the propensity to generate the chlorinated disinfection by-products (DBPs) of chloramines and trihalomethanes (THMs). The protocol makes use of a specially developed body fluid analogue (BFA), containing simulant endogenous organic matter, with a soiling analogue consisting of commercial humic acid (HA). Using this analogue, levels of organic carbon (OC) and chloramines similar to those recorded in real pools have been obtained, along with somewhat lower levels of THMs. Results revealed conventional chlorination leads to steady-state TOC and DBP levels following an equilibrium period of 200-600 hours, with concentration values which are dependent on BFA loading rate. Following equilibration nitrate is the only DBP accumulating in the pool water, accounting for between 4% and 28% of the ammoniacal nitrogen loaded into the pool depending upon the operating conditions (primarily the Cl:N ratio). Both UV irradiation and ozonation, the latter combined with downstream adsorption, provide a similar efficacy in reducing chloramine levels, with their effect on THM and nitrate formation being highly dependent on the pH level and chlorine dose rate. This study builds on previous experimentation by including a more rigorous analysis of ozone-GAC with respect to DBP formation, a unique analysis of UV irradiation and a more comprehensive mass balance calculation of C, Cl and N across the pool. The study has established that no accumulation of carbon takes place in the pool, contrary to postulations made in previous published studies, and that the balance between the chloramines and THM DBPs is significantly affected by the HA loading.

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Li, Wei 1970 May 26. "Dynamic penetration of metalfiber laminates." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=80121.

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Laminates composed of alternating layers of metal and fiber reinforced polymers (FRP's) exhibit a number of properties, which are preferable to either metals or FRP's alone, making them attractive materials for a number of industries, particularly aerospace. A number of questions persist, however, before these new composites can be widely accepted and utilized; one of which is their response to impact, which may occur over a wide range of velocities. Numerical methods, especially the FEA method, have been widely used to simulate the impact response because they can reduce the cost and save time comparing with the experiment. In this work, a continuum damage based model (CDM) is developed and implemented into FEA commercial software ABAQUS. Using a rate-dependent plasticity model for the constitutive behavior of Aluminum and the CDM for the behavior of fiberglass laminates, the dynamic penetration is simulated using ABAQUS. Force vs. displacement results compare well with those obtained from the experiments. In addition, the computed damage region is in close agreement with that seen in sectioned specimens of the tested material. Simulations are also performed for ballistic experiments conducted on 150mm x 150mm clamped panels of the same laminates. Ballistic experiments involve both the local penetration response as well as the global deformation behavior, particularly at velocities near the ballistic limit, where significant flexural deformation takes place. Results from the simulation agree well with the ballistic experiment results. Given the validity of the modeling approach, the high velocity impact response of the other metal/fiber systems can be examined minimizing the need for trial and error fabrication.

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Aly, Sayed. "Dynamics of long rod penetration." Thesis, University of Manchester, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492714.

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Penetration of metallic targets by long rod projectiles is one of the basic research issues of terminal ballistics and impact dynamics. This work contributes to this field through theoretical and numerical investigations of the penetration performance of long rod projectiles, including both monolithic-rod and segmented-rod projectiles, into semi-infinite metallic targets.University of Manchester.

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Stone, David Andrew. "Frontface monitoring of weld penetration." Thesis, University of Liverpool, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.329510.

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Poole, Chris. "Penetration of a shaped charge." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419435.

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A shaped charge is an explosive device used to penetrate thick targets using a high velocity jet. A typical shaped charge contains explosive material behind a conical hollow. The hollow is lined with a compliant material, such as copper. Extremely high stresses caused by the detonation of the explosive have a focusing effect on the liner, turning it into a long, slender, stretching jet with a tip speed of up to 12km/s. A mathematical model for the penetration of this jet into a solid target is developed with the goal of accurately predicting the resulting crater depth and diameter. The model initially couples fluid dynamics in the jet with elastic-plastic solid mechanics in the target. Far away from the tip, the high aspect ratio is exploited to reduce the dimensionality of the problem by using slender body theory. In doing so, a novel system of partial differential equations for the free-boundaries between fluid, plastic and elastic regions and for the velocity potential of the jet is obtained. In order to gain intuition, the paradigm expansion-contraction of a circular cavity under applied pressure is considered. This yields the interesting possibility of residual stresses and displacements. Using these ideas, a more realistic penetration model is developed. Plastic flow of the target near the tip of the jet is considered, using a squeeze-film analogy. Models for the flow of the jet in the tip are then proposed, based on simple geometric arguments in the slender region. One particular scaling in the tip leads to the consideration of a two-dimensional paradigm model of a ``filling-flow'' impacting on an obstacle, such as a membrane or beam. Finally, metallurgical analysis and hydrocode runs are presented. Unresolved issues are discussed and suggestions for further work are presented.

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Street, Paul Raymond. "Mechanisms of skin penetration enhancement." Thesis, Cardiff University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358541.

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Berry, A. J. "The dynamic penetration of clays." Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.235369.

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Ainscough, D. M. "Automatic control of weld penetration." Thesis, University of Liverpool, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234822.

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Nilsson, Robin. "Penetration testing of Android applications." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-280290.

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The market of Android applications is huge, and in 2019, Google Play users worldwide downloaded 84.3 billion mobile applications. With such a big user base, any security issues could have big negative impacts. That is why penetration testing of Android applications is important and it is also why Google has a bug bounty program where people can submit vulnerability reports on their most downloaded applications. The aim of the project was to assess the security of Android applications from the Google Play Security Reward Program by performing penetration tests on the applications. A threat model of Android applications was made where potential threats were identified. A choice was made to focus on the Spotify Application for Android where threats were given ratings based on risks associated with them in the context of the Spotify Application. Penetration tests were made where testing depth was determined by the ratings associated with the attacks.The results of the tests showed that the Spotify Application is secure, and no test showed any real possibility of exploiting the application. The perhaps biggest potential exploit found is a Denial of Service attack that can be made through a malicious application interacting with the Spotify application. The result doesn’t guarantee that the application isn’t penetrable and further testing is needed to give the result more reliability. The methods used in the project can however act as a template for further research into both Spotify and other Android applications.
Marknaden för Android applikationer är enorm och 2019 laddade Google Play användare ner 84.3 miljarder mobil-applikationer. Med en så stor användarbas kan potentiella säkerhetsproblem få stora negativa konsekvenser. Det är därför penetrationstest är viktiga och varför Google har ett bug bounty program där folk kan skicka in sårbarhetsrapporter för deras mest nedladdade applikationer. Målet med projektet är att bedöma säkerheten hos Android applikationer från Google Play Security Reward Program genom utförande av penetrationstester på applikationerna. En hotmodell över Android applikationer skapades, där potentiella hot identifierades. Ett val att fokusera på Spotify för Android gjordes, där hot gavs rankingar baserat på riskerna associerade med dem i kontexten av Spotify applikationen. Penetrationstest gjordes med testdjup avgjort av rankingarna associerade med attackerna.Resultatet av testen visade att Spotify applikationen var säker, och inga test visade på några riktiga utnyttjningsmöjligheter av applikationen. Den kanske största utnyttjningsmöjligheten som hittades var en Denial of Service-attack som kunde göras genom en illvillig applikation som interagerar med Spotify applikationen. Resultaten garanterar inte att applikationen inte är penetrerbar och fortsatt testande behövs för att ge resultatet mer trovärdighet. Metoderna som användes i projektet kan i alla fall agera som en mall för fortsatt undersökning av både Spotify såväl som andra Android applikationer.

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Aodah, Alhassan, and Alhassan Aodah. "Preformulation and Topical Penetration Studies." Diss., The University of Arizona, 2017. http://hdl.handle.net/10150/624589.

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Chapter I: preformulation studies on piperlongumine Piperlongumine is a natural alkaloid extracted from piper plant which has been used traditionally for the treatment of certain diseases. This compound shows interesting in-vitro pharmacological activity such as selective anticancer activity and higher cytotoxicity than methotrexate, cyclophosphamide and adriamycin on breast, colon, and osteosarcoma cancers, respectively. However, the physicochemical properties of this compound have not been well characterized. In this research, preformulation studies for piperlongumine have been performed to determine factors which influence solubility and stability which, in turn, can be used to assist future formulation development. The solubility of piperlongumine in water was found to be approximately 26 μg/ml. Using 10% polysorbate 80 as a surfactant resulted in a 27 fold increase in solubility. Cosolvents and cyclodextrins afforded concentrations of 1 mg/ml and higher. The pH degradation rate profile for piperlongumine at various temperatures shows significant instability of the drug at pH values 7 and 3, and maximum stability around pH 4. It was estimated that it would take approximately 17 weeks for piperlongumine to degrade by 10% at 25°C, pH 4. Additionally, piperlongumine showed marked photo-degradation upon exposure to an ultraviolet light source, especially in aqueous media. Chapter II: preformulation and evaluation of resatorvid topical delivery Resatorvid is a small molecule shows interesting anti- inflammatory biological activity. The clinical trial was conducted for sepsis-induced cardiovascular and respiratory failure, but it was terminated due to low efficacy. Further researches show a different biological activity of resatorvid such as its activity against UV-induced skin cancer. The goal of this study is to determine some important physiochemical properties of resatorvid, as well as intrinsic penetration criteria through the murine skin, either ex-vivo or in-vivo. Intrinsic water solubility of resatorvid was found to be 95.32± 1.75 ug/ml and could be duplicated by using 10 % ethanol as cosolvent. The pH solubility profile shows the acidic pka value of resatorvid is around 8-8.1. Photo-stability results indicate more stability in non-aqueous more than aqueous medium. Resatorvid pH degradation rate profiles indicate the maximum stability between pH3 -5 and maximum instability at pH 8 and 9 at all experimental temperatures over 26 days. T90 at 25 °C was 648 days in pH 3 versus 11 days in pH 9. Ex-vivo penetration evaluation for resatorvid through hairless murine skin was evaluated using acetone and phosphate buffer formulations. The flux values were 0.82 and 0.36 for acetone and phosphate buffer formulation respectively. The percent of drug retention in the dermis layer of skin were also evaluated and found to be 37.99% for the acetone formulation and 21.13 % for phosphate buffer formulation. The in-vivo penetration evaluation study was performed by topically applying of resatorvid in acetone solution. Skin biopsy from the site of application was analyzed one, three, eight and 24 hours post-application. The analysis was performed by tape stripping of the stratum corneum of the skin segment. It was found that percent of resatorvid at the dermis layers 5.92, 1.47, 0.45 and 0.23 % for 1, 3, 8 and 24 hours post-application respectively. The percent of resatorvid retention in dermis layer from the in-vivo study are not in compliance with the result of the ex-vivo study, which could refer to possible enzymatic degradation of resatorvid in the live animal skins. Chapter III: correlation of drug penetration between Strat-MTM membranes and murine skin for various drugs. Strat-MTM is a synthetic model for transdermal diffusion testing made by EMD Millipore and was marketed as a new skin mimetic membrane. It has been reported to be predictive of diffusion in human skin. Independent researchers had evaluated this membrane and compared it with animal and human skin and other polymeric membranes. Yet, there are not a published research to correlate the animal skin and Strat-MTM based on the amount of drug retained after topical application, which is one of the critical criteria for dermal drug delivery system. In this research, five compounds, with various physiochemical properties, were selected to perform this correlation. Resatorvid, Methyl Para aminobenzoate (M-PABA), Diclofenac sodium, Salicylic acid and hydrocortisone, each one was dissolved in phosphate buffer saline (pH 7.4) in concentrations of 60 ug/ml for resatorvid and 100-120 ug/ ml for others. All experiments were uniform in the setting and made in triplicate. As a conclusion from the results, the number of tested compounds were shorted to reflect the correlation in flux or permeability coefficient between murine skin and Strat-MTM membrane. With exception of M-PABA, there is a trend of correlation with the percentage of drug retained in dermis layers; however, the number of compounds still low to reflect a real correlation.

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Algwaiz, Noura. "Modeling Internet Penetration in Canada." Thesis, University of Ottawa (Canada), 2010. http://hdl.handle.net/10393/28733.

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Internet penetration is an important measure for a knowledge-based economy as it indicates how connected it is to the internet. It does not spread evenly across regions and societies, which results in digital divides. Despite being one of the most connected countries, Canada suffers from uneven penetration rates across the country. In this research, we study the socio-economic factors that int1uence Internet penetration in Canada. We found that the int1uence of rurality has decreased between 2005 and 2007, which suggests that initiatives that took place in those two years were effective. We also analyze the differences among the regions of Canada and found that the regions least int1uenced by the demographic variables are not necessarily the ones with the highest penetration rates. Therefore, a mere look at the penetration rates across the regions is not enough to assess the connectivity of the region and the digital divide within.

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Pascual, Christopher C. "EHD enhancement of nucleate pool boiling." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/19027.

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Davis, Gareth Michael. "Mathematical modelling of swimming pool chlorination." Thesis, University of Bristol, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.402341.

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Sriraman, Sharan Ram. "Pool boiling on nano-finned surfaces." [College Station, Tex. : Texas A&M University, 2007. http://hdl.handle.net/1969.1/ETD-TAMU-2091.

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Rawlinson, Rosemary Julia. "Glutathione and the cytosolic heme pool." Thesis, King's College London (University of London), 2018. https://kclpure.kcl.ac.uk/portal/en/theses/glutathione-and-the-cytosolic-heme-pool(e78204fa-e583-41eb-ab9c-1a759b9abf33).html.

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Recently glutathione (GSH) has been proposed as a key component of the cytosolic iron pool, possessing a buffering role for cytosolic iron(II), protecting it from autoxidation. However the chemical nature of the cytosolic heme pool is unknown. We have investigated whether GSH binds heme iron. If so, the resulting complex would be expected to have increased stability and solubility in aqueous solutions, compared to the extremely hydrophobic heme molecule, thereby reducing its ability to partition into membranes. An interaction between glutathione and hematin was established with the affinity constant (Ka) of glutathione for hematin determined by absorption spectroscopy to be 5x104 M-1. Using standard bioassays the influence of GSH on heme oxidase activity and the partitioning of hematin into lipid bilayers was assessed. GSH was found to stabilise hematin in the presence of H2O2 and was found to have a profound effect on the partitioning of hematin into lipid bilayers, reducing partitioning into prepared liposomes by < 70%. The presence of hematin ligated to GSH within the lysate of mammalian cells was established using synthesised [59Fe]hematin, Caco-2 cells and size exclusion HPLC. These results suggest that GSH could be the predominant ligand for the cytosolic heme pool. The effect of glutathione on absorption and catabolism of hematin in Caco-2 cells showed an initial decrease in hematin uptake and a decrease in heme oxygenase 1 expression. Hematin when ligated to GSH, in the presence of ascorbic acid and O2, was found to be rapidly degraded and whilst GSH decreases hematin partitioning into erythrocyte plasma membranes, the effect was not as dramatic as was observed in liposomes. These results did not provide further support for glutathione serving as the predominant ligand for the organic iron pool and led to the conclusion that heme is chaperoned (not by glutathione) and encapsulated within endosomes in the cytosol. It is proposed that GSH and ascorbic acid function cooperatively to rapidly ligate and degrade any heme which escapes from the endosome system into the cytosol, hence preventing ferroptosis.

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Shawkat, Salman, and Ragheed Hussain. "Concrete Cracks in Swimming Pool Basins." Thesis, KTH, Byggnadsteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-208349.

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Majority of the swimming facilities in Sweden are facing some form of renovation or total substitution. The report analyses cracks in two different public bath facilities namely Eriksdalsbadet and Enskedehallen. The text also discusses different solution strategies for cracks in concrete. The aim with this thesis is to discuss how facility managers can extend the service life of these facilities by taking measures against the crack damages. Since renovation can be expensive, it is important to study cracks early on when they appear. This thesis also emphasizes on how important it is to add resources for preventing cracks, already during casting. Resources should also be added for maintaining the basins, managing repair methods for all types of cracking problems. This thesis is more of a generalized study for cracks in concrete, however it concludes with taking a more specific approach by discussing the problems in swimming basins. Causes of cracks, different types of cracks and evolution of cracks are studied and discussed with emphasis on the structural damages that can occur. With pictures taken and analyzed from the two facilities and a visitation with a experienced concrete investigator from CBI, this thesis concludes with a decision to immediately take repair actions against cracks that are shown in the report. The report discusses two perspectives, one where the authors of the thesis discusses solutions derived from information given in the report, and the other perspective is derived from guided inspection with consultant from CBI.
Neris projektet

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Deniz, Tansel. "Ballistic Penetration Of Hardened Steel Plates." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613534/index.pdf.

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Ballistic testing is a vital part of the armor design. However, it is impossible to test every condition and it is necessary to limit the number of tests to cut huge costs. With the intro- duction of hydrocodes and high performance computers
there is an increasing interest on simulation studies to cutoff these aforementioned costs. This study deals with the numerical modeling of ballistic impact phenomena, regarding the ballistic penetration of hardened steel plates by 7.62 mm AP (Armor Piercing) projectile. Penetration processes of AP projectiles are reviewed. Then, a survey on analytical models is given. After the introduction of fun- damentals of numerical analysis, an intensive numerical study is conducted in 2D and 3D. Johnson Cook strength models for the four different heat treatments of AISI 4340 steel were constructed based on the dynamic material data taken from the literature. It was found that 2D numerical simulations gave plausible results in terms of residual projectile velocities, con- sidering the literature review. Then, 3D numerical simulations were performed based on the material properties that were selected in 2D studies. Good agreement was obtained between the numerical and test results in terms of residual projectile velocities and ballistic limit thick- nesses. It was seen that the ballistic protection efficiency of the armor plates increases with the increasing hardness, in the examined range. This study is a part of T¨
ubitak project 106M211 of MAG.

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Szulczyk, Kenneth Ray. "Market penetration of biodiesel and ethanol." Texas A&M University, 2003. http://hdl.handle.net/1969.1/5822.

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This dissertation examines the influence that economic and technological factors have on the penetration of biodiesel and ethanol into the transportation fuels market. This dissertation focuses on four aspects. The first involves the influence of fossil fuel prices, because biofuels are substitutes and have to compete in price. The second involves biofuel manufacturing technology, principally the feedstock-to-biofuel conversion rates, and the biofuel manufacturing costs. The third involves prices for greenhouse gas offsets. The fourth involves the agricultural commodity markets for feedstocks, and biofuel byproducts. This dissertation uses the Forest and Agricultural Sector Optimization Model-Greenhouse Gas (FASOM-GHG) to quantitatively examine these issues and calculates equilibrium prices and quantities, given market interactions, fossil fuel prices, carbon dioxide equivalent prices, government biofuel subsidies, technological improvement, and crop yield gains. The results indicate that for the ranges studied, gasoline prices have a major impact on aggregate ethanol production but only at low prices. At higher prices, one runs into a capacity constraint that limits expansion on the capacity of ethanol production. Aggregate biodiesel production is highly responsive to gasoline prices and increases over time. (Diesel fuel price is proportional to the gasoline price). Carbon dioxide equivalent prices expand the biodiesel industry, but have no impact on ethanol aggregate production when gasoline prices are high again because of refinery capacity expansion. Improvement of crop yields shows a similar pattern, expanding ethanol production when the gasoline price is low and expanding biodiesel. Technological improvement, where biorefinery production costs decrease over time, had minimal impact on aggregate ethanol and biodiesel production. Finally, U.S. government subsidies have a large expansionary impact on aggregate biodiesel production, but only expand the ethanol industry at low gasoline prices. All of these factors increase agricultural welfare with most expanding producer surplus and mixed effects on consumers.

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Hansson, Håkan. "Warhead penetration in concrete protective structures." Licentiate thesis, KTH, Betongbyggnad, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-48009.

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The analysis of penetration of warheads in concrete protective structures is an important part of the study of weapon effects on protective structures. This type of analysis requires that the design load in the form of a warhead is determined, and its characteristic and performance within a protective structure is known. Constitutive equations for concrete subjected to weapon effects have been a major area of interest for a long time, and several material models for concrete behaviour are developed. However, it is not until recent years that it has been possible to use finite element (FE) analyses to simulate the behaviour of concrete targets during projectile penetration with acceptable results. The reason for this is a combination of several factors, e.g. development of suitable material models for concrete, enhancement of numerical methodology and affordable high capacity computer systems. Furthermore, warhead penetration has primary been of interest for the armed forces and military industry, with a large part of the conducted research being classified during considerable time. The theoretical bases for concrete material behaviour and modelling with respect to FE analyses of projectile penetration are treated in the thesis. The development of weapons and fortifications are briefly discussed in the thesis. Warheads may be delivered onto a protective structure by several means, e.g. artillery, missiles or aerial bombing, and two typical warhead types were used within the study. These warhead types were artillery shells and unitary penetration bombs for the use against hardened targets, with penetration data for the later warhead type almost non-existing in the literature. The penetration of warheads in concrete protective structures was therefore studied through a combination of experimental work, empirical penetration modelling and FE analyses to enhance the understanding of the penetration phenomenon. The experimental data was used for evaluation of empirical equations for concrete penetration and FE analyses of concrete penetration, and the use of these methods to predict warhead penetration in protective structures are discussed within the thesis. The use of high performance concrete increased the penetration resistance of concrete targets, and the formation of front and back face craters were prevented with the use of heavily reinforced normal strength concrete (NSC) for the targets. In addition, the penetration depths were reduced in the heavily reinforced NSC. The evaluated existing empirical penetration models did not predict the behaviour of the model scaled hardened buried target penetrators in concrete structures with acceptable accuracy. One of the empirical penetration models was modified to better describe the performance of these penetrators in concrete protective structures. The FE analyses of NSC gave reasonable results for all simulation cases, with the best results obtained for normal impact conditions of the penetrators.
Analyser avseende stridsdelars penetration i skyddskonstruktioner av betong viktigt för studier av vapenverkan mot skyddskonstruktioner. Dessa analyser förutsätter att dimensionerande last i form av stridsdel bestäms, samt att dess karakteristik och verkan mot skyddskonstruktioner är kända. Konstitutiva modeller för betong utsatta för vapenverkan har varit av stort intresse under en lång tid och ett flertal materialmodeller har utvecklats. Det är emellertid först på senare år som det varit möjligt att använda finita element (FE) analyser for att simulera beteendet för betongmål vid projektilpenetration med acceptabla resultat. Anledningen till detta kan tillskrivas kombinationen av ett flertal faktorer, t ex utvecklingen av lämpliga materialmodeller, förbättringar av numerisk metodik och utvecklingen av kostnadseffektiva beräkningsdatorer. Penetration av stridsdelar har dessutom i huvudsak varit av intresse för militären och försvarsindustrin, vilket har resulterat i att en stor del av den bedrivna forskningen har varit hemligstämplad under lång tid. Grunderna avseende betongs materialbeteende och beskrivning av detta med avseende på FE-analyser av projektilpenetration behandlas i denna licentiatuppsats. Den fortifikatoriska utvecklingen och utvecklingen av vapen diskuteras kortfattad i uppsatsen. Ett flertal olika typer av stridsdelar är av intresse avseende verkan mot skyddskonstruktioner, t ex artillerigranater, missiler eller flygbomber. I denna studie beaktades två typiska stridsdelar, artillerigranater och penetrerande bomber. De senare är specifikt konstruerade för användande mot skyddskonstruktioner och företrädesvis mot betongkonstruktioner. Det visade sig dessutom att data avseende penetration i betong för denna typ av penetrerande stridsdelar i stort sett inte var publicerade. Penetration av stridsdelar i betong studerades därför med en kombination av experimentella metoder, empiriska penetrationsmodeller och FE-analyser för att öka förståelsen för problemställningen. De experimentella modellresultaten användes för att utvärdera både de empiriska penetrationsmodellerna och FE-analyserna avseende betongpenetration, med båda metodernas användande diskuterat i uppsatsen. Användandet av högpresterande betong ökade penetrationsmotståndet för betongmålen i jämförelse med standardbetongmålen. Det var även möjligt att förhindra kraterbildningen på fram- och baksidan av de kraftigt armerande standardbetongmålen, detta medförde även en reducerad penetration för projektilerna i målen. De existerande empiriska penetrationsmodellerna kunde inte förutsäga penetrationen av modellprojektilerna i betongmålen med godtagbara resultat. Istället vidareutvecklades en av dessa modeller för att bättre beskriva denna typ av penetrerande stridsdelar i skyddskonstruktioner av betong. Finita elementanalyserna av standardbetongmålen visade sig ge ett rimligt beteende för alla analyserade modeller, med de bästa resultaten erhållna för vinkelrätt anslag för de modellprojektilerna av de penetrerande stridsdelarna.
QC 20111116

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Hurtig, Tomas. "Plasma cloud penetration across magnetic boundaries." Doctoral thesis, KTH, Alfvén Laboratory, 2004. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3804.

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Grytten, Frode. "Low-Velocity Penetration of Aluminium Plates." Doctoral thesis, Norwegian University of Science and Technology, Department of Structural Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-2123.

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The present thesis describes research on quasi-static and low velocity perforation of rolled aluminium plates, where the main objective has been to gain a better knowledge of the physical processes taking place during this type of structural problem. The objective has been met by a combination of laboratory tests, material modelling and non-linear finite element simulations.

The thesis is organized in a synopsis, giving a brief introduction to the problem and summarising the main findings and conclusions, in addition to four independent papers.

Paper I presents an experimental technique for measuring the deformations the plate undergoes during impact and perforation. This information can be used to validate numerical models and to increase the understanding of how energy is absorbed by the plate.

Paper II presents an experimental and numerical investigation on the quasi-static perforation of AA5083-H116 aluminium plates. In the tests, square plates were mounted in a circular frame and penetrated by a cylindrical punch. A full factorial design was used to investigate the effects of varying plate thickness, boundary conditions, punch diameter and nose shape. Based on the obtained results, both the main and interaction effects on the maximum force, displacement at fracture and energy absorption until perforation were determined. The perforation process was then computer analysed using the nonlinear finite element code LS-DYNA. Simulations with axisymmetric elements, brick elements and shell elements were conducted. Slightly modified versions of the Johnson-Cook constitutive relation and fracture criterion were used to model the material behaviour. It was shown that the FEM models were able to predict the trends observed in experiments.

Paper III evaluates methods for determination of the anisotropic properties of polycrystalline metallic materials. Four calibration methods were evaluated for the linear transformation-based anisotropic yield function YLD2004-18p (Barlat et al., 2005) and the aluminium alloy AA5083-H116. The different parameter identifications are based on least squares fits to combinations of uniaxial tensile tests in seven directions with respect to the rolling direction, compression (upsetting) tests in the normal direction and stress states found using the full-constraint (FC) Taylor model for 690 evenly distributed strain paths. An elastic-plastic constitutive model based on YLD2004-18p has been implemented in a non-linear finite element code and used in finite element simulations of plane-strain tension tests, shear tests and upsetting tests. The experimental results as well as the Taylor model predictions can be satisfactorily reproduced by the considered yield function. However, the lacking ability of the Taylor model to quantitatively reproduce the experiments calls for more advanced texture models.

Paper IV presents an experimental and numerical investigation on low velocity perforation of AA5083-H116 aluminium plates. In the tests, square plates were mounted in a circular frame and penetrated by a cylindrical blunt-nosed projectile. The perforation process was then computer analysed using the nonlinear finite element code LS-DYNA, in order to investigate the effects of anisotropy, dynamic strain aging and thermal softening in low velocity impacts on the present aluminium alloy. Dynamic strain aging has been shown to influence both the predicted force level and fracture, while thermal softening only influences the fracture prediction. No effect of plastic anisotropy was observed.

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Lu, Yuebin. "Deep penetration microindentation testing of polymers." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape4/PQDD_0019/NQ58147.pdf.

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Khan, Ali Akbar. "Bacterial penetration into root canal dentine." Thesis, Click to view the E-thesis via HKUTO, 2007. http://sunzi.lib.hku.hk/HKUTO/record/B39556918.

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Patzelt, Alexa [Verfasser]. "Follikuläre und transfollikuläre Penetration / Alexa Patzelt." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2017. http://d-nb.info/1135608113/34.

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Hanh, Bui Duc, Ulrike Günther, Marcus Hartmann, Siegfried Wartewig, and Reinhard Neubert. "Drug penetration studied by FTIR methods." Universitätsbibliothek Leipzig, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-194960.

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Hill, E. M. H. "The foliar penetration of polar compounds." Thesis, Liverpool John Moores University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.379437.

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Williams, Daffydd Griffin. "Mechanism of action of penetration enhancers." Thesis, Cardiff University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.320625.

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Moss, Timothy. "Phase II metabolism during percutaneous penetration." Thesis, University of Newcastle Upon Tyne, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.362473.

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Miller, Paul. "Sulfur Mustard penetration of thermoplastic elastomers." Fishermans Bend Vic. : Defence Science and Technology Organisation, 2008. http://nla.gov.au/nla.arc-24764.

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Aronsson, Erik. "Biometric Authentication and Penetration of Smartphones." Thesis, Högskolan i Halmstad, Akademin för informationsteknologi, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-37713.

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This study aims to examine the function and vulnerabilities of biometric systemsintegrated in smartphones, as well as techniques for circumventing the securityof these systems. These techniques are then used against a selection of smart-phones in order to gauge the resilience of their biometric security. The function,vulnerabilities, and techniques associated with these systems are compiled usinga literature study of published papers and books on the subject. The performedexperiments apply these techniques in the form of presentation attacks directed atthe fingerprint-, face- and iris recognition systems of the examined smartphones.The result of the experiments showed significant differences between the differentsmartphones, where some exhibited flawless security and others showed significantsecurity flaws. Both fingerprint and face recognition systems were successfullycircumvented, while none of the iris recognition systems were breached. No clearlink could be observed between the cost of the device and success rate of attacks,while only devices using the Android operating system were breached. The resultsundeniably showed that some smartphones are vulnerable to the employed tech-niques. It also showed that some of the tested devices had managed to implementmeasures to counteract the applied presentation attacks. The root cause of thevulnerabilities showcased in the experiment is due to the fact that biometric traitscan be copied and reproduced, highlighting a basic flaw of such systems.

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Hanh, Bui Duc, Ulrike Günther, Marcus Hartmann, Siegfried Wartewig, and Reinhard Neubert. "Drug penetration studied by FTIR methods." Diffusion fundamentals 3 (2005) 31, S. 1, 2005. https://ul.qucosa.de/id/qucosa%3A13271.

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McCallum, Adrian Bruce. "Cone penetration testing in polar snow." Thesis, University of Cambridge, 2012. https://www.repository.cam.ac.uk/handle/1810/244073.

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Innovative Cone Penetration Testing (CPT) using adapted commercial CPT equipment was conducted in Antarctica in early 2010 in an attempt to assess the strength of polar snow; additionally, application of CPT data was considered, particularly in estimating surface bearing capacity. Almost 100 CPT tests were carried out and both qualitative and quantitative analysis of data was undertaken. Additional supporting testing in- cluded snow density assessment, snow strength assessment, extrapolation of CPT data via Ground Penetrating Radar (GPR) and preliminary mini-cone penetrometer testing in Greenland. Analysis of results revealed that assessing the strength of polar snow via CPT is affected by numerous factors including penetration rate, cone size/shape and snow material properties, particularly compaction of the snow undergoing penetration. A density-dependant relationship between CPT resistance and snow shear strength was established, and methods for estimating surface bearing capacity directly from CPT in homogeneous and layered polar snow were proposed. This work applied existing technology in a new material and shows that CPT can be used efficiently in polar environs to provide estimates of snow shear strength and surface bearing capacity, to depths of 10 m or more.

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Armstrong, Paul John. "Projectile penetration into fibre reinforced concrete." Thesis, University of Sheffield, 1987. http://etheses.whiterose.ac.uk/10217/.

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A wide range of fibre reinforced concretes, potentially capable of sprayed application, and which could be used for protecting buildings, has been tested. Specimens 450mm square have been impacted by 7.62mm A. P. projectiles, and the damage assessed in terms of penetration path lengths within the specimens and the volume of the impact face spall crater. It has been found that inclusion of fibres does not increase the penetration resistance, but a small proportion of fibres significantly reduces the impact face spalling. The mechanisms of penetration and spalling have been examined using high speed photographic techniques and instrumented specimens.

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Daniel, Christopher Ryan. "Energy transfer and grain size effects during the Standard Penetration Test (SPT) and Large Penetration Test (LPT)." Thesis, University of British Columbia, 2008. http://hdl.handle.net/2429/775.

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The Standard Penetration Test (SPT) is the most widely used in-situ soil test in the world. "Large Penetration Test" (LPT) is a term used to describe any scaled up version of the SPT. Several types of LPT have been developed around the world for the purpose of characterizing gravel deposits, as SPT blow counts are less reliable in gravels than in sands. Both tests suffer from the lack of a reliable means of determining transferred energy. Further, the use of LPT blow counts is generally limited to calculation of equivalent SPT blow counts using correlation factors measured in sands. Variation of LPT blow counts with grain size is assumed to be negligible. This research shows that safety hammer energies can be reliably estimated from measurements of hammer impact velocity for both SPT and LPT. This approach to determining transferred energy is relatively simple, and avoids the primary limitation of existing methods, which is the inability to calibrate the instrumentation. Transferred energies and hammer impact velocities are collected from various sources. These data are used to determine the ratio between the hammer kinetic energy and the transferred energy (energy transfer ratio, ETR), which is found to follow a roughly Normal distribution for the various hammers represented. An assessment of uncertainty is used to demonstrate that an ETR based approach could be superior to existing energy measurement methods. SPT grain size effects have primarily been characterized as the variation of an empirical relative density correlation factor, (CD)SPT, with mean grain size. In this thesis, equivalent (CD)LPT data are back-calculated from measured SPT-LPT correlation factors (CS/L). Results of a numerical study suggest that SPT and LPT grain size effects should be similar and related to the ratio of the sample size to the mean grain size. Based on this observation, trend-lines with the same shape as the (CD)SPT trend-line are established for the back-calculated (CD)LPT data. A method for generating the grain size effect trend-line for LPT is then proposed. These trend lines provide a rational approach to direct interpretation of LPT data, or to improved prediction of equivalent SPT blow counts.

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