>Magister Scientiae - MSc / Understanding fluid flow and solute transport within the vadose (unsaturated) zone is an essential prerequisite for protection of groundwater from contaminant sources occurring overland. Preferential flow paths in the vadose zone pose a significant problem because they are potential avenues for rapid transport of chemicals from contamination sources to the water table. The objectives of this study were: i) To review and understand flow and transport processes in unsaturated zones. In this study, particular emphasis is placed on understanding mechanisms that cause non-uniform (preferential) flow for two case studies, namely the Cape Flats sandy environment and the Mpumalanga Highveld fractured rock environment. ii) To evaluate the adequacy of models, in particular MACRO 5.0, in simulating flow and transport in the vadose zone, by making use of two case study sites (Cape Flats and Mpumalanga Highveld). Of particular importance is the evaluation of transfer coefficients to represent fluid and solute exchange between macropores and matrix. iii) To run a sensitivity analysis with MACRO 5.0 in order determine which input model parameters are the most relevant in describing the effects of preferential flow in water and solute transport. Two case studies were investigated, the first at a landfill site overlying sandy unconfined aquifer (Coastal Park, Cape Town), and the second at an industrial site overlying cracking clayey soil and fractured rocks (Mpumalanga Highveld - Secunda, Mpumalanga Province). For the Coastal Park site, simulations of soil water content and leaching of a generic mobile contaminant were compared to monitored soil water contents and chloride concentrations in groundwater. For the Mpumalanga Highveld site, simulations of soil water content and concentrations of boron and fluoride originating from effluent irrigation were compared to soil profile measurements. In both cases, the MACRO 5.0 model predictions agreed with measurements well, provided appropriate input calibration data were used. The sensitivity analysis indicated that soil water properties related to preferential flow (hydraulic conductivity at the boundary between macropores and matrix, soil water content and tension, and diffusion) have influence on simulation results. Similarly, the solute balance is mostly influenced by degradation rate coefficients (both in solid and liquid phases), sorption distribution coefficients and solute concentrations.

Indiana University-Purdue University Indianapolis (IUPUI) / Health care automation provides opportunities for health care agencies to save time, save money, and increase patient safety. The Department of Veterans Affairs medical centers use a program, Attachmate Reflections, for pharmacy medication order verification. This program is a command line interface that allows the use of macros, or programmed automated routines, that have the ability to automate repetitive tasks. Through the use of macro programming at the VISN 11 VA medical centers, this author was able to automate converting patients from Combivent MDI inhalers to its successor Combivent Respimat inhalers due to the MDI inhaler being withdrawn from the market. Usage of the macro resulted in a time savings of 649.1 hours, cost savings of $32,748.36, and increased patient safety by providing consistent medication instructions, correct dispense quantities, correct prescription day supply, and correct number of refills remaining on the prescription.

This study focuses on the importance of intrinsic and extrinsic work rewards among women and men in 12 post-industrial nations in the Global North. Guiding my analyses was Esping-Andersen’s theoretical framework and the following three main research questions: (1) how individual attributes and national policies influence the salience individuals assign to intrinsic and extrinsic rewards; (2) how individual attributes and national policies differ from each other in relative magnitude as predictors of the value individuals assign to intrinsic and extrinsic rewards; and (3) how individual attributes and national policies impact the importance individuals assign to intrinsic and extrinsic rewards differs by gender. For the micro level analysis, I used data from the 2005 International Social Survey Program Work Orientation Module. The twelve countries included in the analysis are Australia, Denmark, Belgium, Canada, Finland, France, Germany, Ireland, Norway, Sweden, United Kingdom, and the United States. Macro level policy data are drawn from the 2005 Social Expenditure Database and maternity leave data are from the 2005 International Network on Leave Policy and Research. Analysis was performed using Stata regression with the cluster command. While not all variables included in the model were statistically significant, the general hypotheses were supported with the following results: (1) micro level variables (education, income, and employment) and macro level variables (paid family leave and the percentage of GDP spent on childcare and pre-primary education) increased the importance individual’s assign to intrinsic rewards; (2) the lack of human capital increases an individual’s emphasis on extrinsic rewards; (3) while macro level variables have a far greater impact on the importance individuals assign to intrinsic work rewards, both micro and macro level factors are important for explaining the maximum possible variation in the importance individuals assign to intrinsic work rewards; and (4) gender does not change the value an individual assigns to intrinsic or extrinsic rewards. This study represents a new, more comprehensive approach to studying the relationships among micro-level factors, structural opportunities and constraints, intrinsic and extrinsic work rewards, and gender. A review of the literature shows no other studies of this scope.

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The excellent lubrication present within mammalian synovial joints attracted scientific interest, and some close-to-realistic models were applied to study the mechanism in vitro. In this project, the synergistic lubrication of synovial fluid was investigated by using 1,2-Dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC), hyaluronic acid (HA), and phosphate-buffered saline (PBS buffer) to mimic the synovial fluid. Lubrication by the model synovial fluid was studied using borosilicate glass specimens in Mini-Traction Machine (MTM). The experiments proved that the DPPC vesicle solution and mixed DPPC/HA solution had excellent lubrication ability, stemming both from adsorption of a lubricious layer at the surface of glass specimens and from presence of material reservoir available for repair of wear defects in the lubricious layer. Comparing the macroscale results obtained in this project by MTM with the results in previous studies on microscale by using AFM, we concluded that the microscale study of synergistic lubrication could predict macroscale results, even though some differences were detected due to limited possibilities for exact replication of experimental conditions at the two scales.

The report reviews macro segregations in continuous cast steels and possible correlations to impact toughness. The purpose of the thesis is to investigate centreline segregates and V-segregates to see which of them that affect impact toughness the most. Apart from a literature study, Charpy-V data was collected with permission from SSAB for two steel types, grade A and grade B, each with respective dominant segregation type. The collected data was yielded in three individual Charpy-V tests at different spots on the metal sheet, derived within a close area. The average value of these tests were used in statistical analysis to observe the spread of values in different heats of the two steels. Additionally, the specimens were etched and captured in cross-section. Results indicated that for the data of grade A, where centreline segregates were dominant, the spread of values was higher than for the data of grade B. The conclusion is that centreline segregations are worse in relation to impact toughness, since higher deviations translates to less predictable properties from a customers perspective. / Denna rapport granskar makrosegringar i stränggjutet stål och eventuella kopplingar till slagseghet. Centrumsegringar och V-segringar undersöks för att undersöka vilken segringstyp som har störst effekt på slagseghet, vilket är syftet med denna avhandling. Förutom en litteraturstudie, hämtades Charpy-V data med SSAB’s medgivande från två olika stålsorter, kvalitet A och kvalitet B, med respektive dominant segringstyp. Datan som inhämtades erhölls från tre stycken Charpy-V tester för varje plåt, från ett närliggande område. Medelvärdet för dessa datapunkter användes i statistisk analysför att obeservera spridningen av datapunkter i olika charger av de två stålen. Dessutom, erhölls segringsbilder för respektive slab från SSAB. Resultaten visade att datapunkterna för kvalitet A, som hade centrumsegring som domiant segringstyp, var mer spridd än datan för kvalitet B. Således, är slutsatsen att centrumsegring är värre i relation till slagseghet eftersom en högre avvikelse leder till mindre förutsägbara egenskaper från en kunds perspektiv.

Recently, machine learning and deep neural networks (DNNs) have gained a significant amount of attention since they have achieved human-like performance in various tasks, such as image classification, recommendation, and natural language processing. As the tasks get more complicated, people build bigger and deeper networks to obtain high accuracy, and this brings challenges to existing hardware on fast and energy-efficient DNN computation due to the memory wall problem. First, traditional hardware spends a significant amount of energy on moving the data between memory and ALU units. Second, the traditional memory blocks only support row-by-row access, and this limits the computation speed and energy efficiency. In-memory computing (IMC) is one promising measure to solve the aforementioned problems in DNN computation. This approach combines the memory blocks with the computation units to enable high computation throughput and low energy consumption. On the macro level, both digital and analog-mixed-signal (AMS) IMC macros achieve high performance in the multiply-and-accumulation (MAC) computation. The AMS designs have high energy efficiency and highcompute density, and the digital designs have PVT robustness and technology scalability. On the architecture level, specialized hardware accelerators that integrate these IMC macros outperform the traditional hardware accelerators in end-to-end DNN inference. Beyond the IMC, other approaches also reduce energy consumption. For example, sparsity-aware training reduces the arithmetic energy by adding more zeros to the weights and zero-gating the multiplication and/or addition. Weight and activation compression reduces the off-chip memory access energy. This thesis presents new circuit and architecture designs for efficient DNN inference with in-memory computing architectures. First, this thesis presents two SRAM-based analog-mixed signal IMC macros. One is a macro with custom 10T1C cells for binary/ternary MAC operation. The other one, MACC-SRAM, is a multistep-accumulation capacitor-based IMC macro for 4b MAC computation. The macro features stepwise charging and discharging, sparsity optimization, and adder-first architecture for energy efficiency. Second, we propose a programmable DNN accelerator that integrates 108 AMS IMC macros. This accelerator, named PIMCA, with its own pipeline structure and instruction set architecture, can flexibly support the inference at the instruction level. Last, we implement a fully-digital accelerator that integrates IMC macros supporting floating-point number computation. The accelerator contains online decompression hardware to reducedata movement energy of weight and activation. It also contains online activation compressors to reduce the activation memory footprint.

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Additive manufacturing methods for steel are competing against commercial production in an increasing pace. The geometry freedom together with the high strength and toughness due to extreme cooling rates make this method viable to use for high-performance components. The desirable material properties originate from the ultrafine grain structures. The production is often followed by a post hardening heat treatment to induce precipitation of other phases. The printing process does however bring several challenges such as cracking, pore formation, inclusions, residual stresses and distortions. It is therefore important to be able to predict the properties such as temperature evolution and residual stresses of the resulting part in order to avoid time consuming trial-and-error and unnecessary material waste. In order to link different parts and length scales of the process, the integrated computational materials engineering framework can be used where linkage tools couples results of different length scales. 18Ni300 maraging steel is a material that has been used extensively to produce parts by additive manufacturing, but there is still a wide scope for optimising the process and properties. In this thesis, the integrated computational materials engineering inspired framework is applied to link the process to the microstructure, which dictates the properties. Temperature evolution strongly influences the material properties, residual stresses and distortion in additive manufacturing. Therefore, simulations of temperature evolution for a selective laser melted 18Ni300 maraging steel have been performed by Simufact Additive and linked with the microstructure prediction tools in Thermo-Calc and DICTRA. Various printing parameters have been examined and resulting temperatures, cooling rates, segregations and martensitic start temperatures compared for different locations of the build part. Additionally, residual stresses and distortions were investigated in Simufact. It was found that higher laser energy density caused increased temperatures and cooling rates which generally created larger segregations of alloying elements and lower martensitic start temperatures at the intercellular region. There is however an impact from cooling rate and temperature independent of the energy density which makes energy density not an individual defining parameter for the segregations. By decreasing the baseplate temperature, lower temperatures below the martensitic start temperature were reached, enhancing martensite transformation. Primary dendrite arm spacing calculations were used to validate the cooling rates. The cell size corresponded well to literature of <1 μm. Distortions and residual stresses were very small. The calibration was based according to literature and need experimental values to be validated. The integrated framework demonstrated in this thesis provides an insight into the expected properties of the additively manufactured part which can decrease and replace trial-and-error methods. / dditiva tillverkningsmetoder för stål tävlar mot kommersiell produktion i en ökande takt. Geometrifriheten tillsammans med hög styrka och slagseghet på grund av extrema kylhastigheter gör den här metoden intressant att använda för högpresterande komponenter. De önskvärda materialegenskaperna härstammar från den ultrafina mikrostrukturen. Processen följs ofta av en värmebehandlande härdning för att inducera utskiljningar av andra faser. Printing processen innebär dock flertalet utmaningar som exempelvis sprickbildning, porer, inneslutningar, restspänningar och förvrängningar. Det är därför intressant och viktigt att förutspå egenskaper såsom temperaturutveckling och restspänningar av den slutgiltiga komponenten för att minska tidskrävande ”trial-and-error” och onödigt materialsvin. För att länka ihop olika delar och längdskalor av processen kan ”the integrated computational materials engineering” strukturen användas där länkverktyg kopplar ihop resultat av olika längdskalor. 18Ni300 maraging stål är ett material som har använts till additivt tillverkade produkter i hög utsträckning men det finns fortfarande mycket utrymme för optimering av processen och egenskaperna. I den här avhandlingen, den ”integrated computational materials engineering” inspirerade tillvägagångssättet används för att länka processen med mikrostrukturen, vilken bestämmer egenskaperna. Temperaturutveckling påverkar kraftigt materialegenskaper, restspänningar och deformation vid additiv tillverkning. Förutsägelse av temperatur för ett selektivt lasersmält 18Ni300 stål har därför genomförts i Simufact Additive och länkats med mikrostruktursförutsägande redskapen Thermo-Calc och DICTRA. Olika maskinparametrar har undersökts och efterföljande temperaturer, kylhastigheter, segregeringar och martensitiska starttemperaturer jämförts för olika delar av geometrin. Tilläggningsvis var även restspänningar och deformationer undersökta i Simufact. Det konstaterades att högre energidensitet för lasern orsakade högre temperaturer och kylhastighet vilket generellt skapade mer segregeringar av legeringsämnen och lägre martensitisk starttemperatur i de intercellulära områdena. Det är däremot en gemensam påverkan av kylhastighet och temperatur vilket gör att energidensitet inte är den enskilda bestämmande parametern över segregeringarna. Genom att sänka temperaturen på basplattan uppnåddes lägre temperaturer under den martensitiska starttemperaturen vilket förenklar den martensistiska omvandlingen. Beräkningar av primär dendritisk armlängd användes för att validera kylhastigheterna. Cellstorleken överensstämde bra med litteraturen på <1 μm. Deformationer och restspänningar var väldigt små. Kalibreringarna baserades på litteraturvärden och kräver experimentella värden för att valideras. Den integrerade strukturen  som demonstreras i den här avhandlingen förser en insikt i de förväntade egenskaperna av en additivt tillverkad del vilket kan minska och ersätta ”trial-and-error” metoder.

The purpose of this investigation is to examine how landscape architecture can create a different kind of threshold between land and water without controlling the edge between the two entities, but merely guiding the natural process of exchange. The design of Oyster Harbor on the Eastern Shore of Virginia is in contrast to normative development of waterfront sites. The hard edge of common practices of waterfront development stands in tension to the more natural evolving edge of many harbors.When creating a dialogue between land and water, the solution has always been to create a sea wall separating the two entities. It becomes the hard dividing line between a solid surface and liquid life. Is there a way to create a threshold that does not divide? How can landscape architecture create an exchange of qualities with land and water? Does the sea wall become the precedent to all concerns of tide and sea usurping lands edge? The edge between land and water is ever changing, so why not celebrate and personify that edge through creating a natural exchange between water and land. In order to create such an exchange, we must first look at the nature of water and land. Water is a free element that is composed of hydrogen and oxygen. It is inclined to motion, reflection, rise and fall. It holds a unique quality independent of man-induced control. Land is a more solid entity created by layers of stone and elements broken down by water. Land capacity is gauged by water, as in the water table. Throughout history, man has maintained a controlling relationship with land. However this is the opposite with water. Man has an inherent fear of water, the representative of both life and death. Though man tries, he cannot control water, he must work within the bounds set by water. How does one understand the evolutionary relationship of land and water without trying to control the elements that allow the relationship to occur? Through research, it is revealed that land actually usurps water through both a push and pull method of tides and water run off from land. Through time and tide, land builds up and infringes upon the natural edge of land and water. The plains move down, the vegetative roll moves forward, the beach ridges reconfigure, and the tidal flats create a shelf that extends out into the ocean floor.This evolution of land continually cycles on moon and sun paths that dictate the change in light, shade, wind, tides, motion, and human cycles. Whether recognizable or not recognizable, these macro and micro environmental cycles become a dance in the realm of landscape architecture. How does one reveal macro and micro environmental aspects through design with human interaction at the edge between land and water? / Master of Landscape Architecture