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This thesis studies the interaction between the bare Cu{311} surface with NO and NH3,individually and co-adsorbed using reflection-absorption infrared spectroscopy (RAIRS). In addition to the bare Cu{311} surface, the interaction of NO and NH3 with the various oxygen phases of the Cu{311} surface phases was also studied. Several other techniques were used in tandem to support the study, such as low energy electron diffraction (LEED) and temperature programmed desorption (TPD) experiments using mass spectrometry. The study was carried out in pursuit an understanding of the underlying mechanism of the selective catalytic reduction (SCR) of NO using NH3 in current diesel engines. The dosing of NO onto the Cu{311} surface at 100 K leads to the initial adsorption of intact NO. After an exposure threshold is reached, individual NO molecules react with another NO molecule to form (NO)2 dimers. These dimer species subsequently form N2O, leaving O(a) on the surface. Oxygen was found to be an inhibitor for the reaction, either due to the reaction in a self-poisoning process or from oxygen pre-dosing onto the Cu{311} surface. Temperature plays a minor role with regards to NO/Cu{311}, as it only affects the amount of NO on the surface along with adsorbate surface mobility. Similarly, NH3 was found to adsorb intact onto the Cu{311} surface and not to react or dissociate at 100 K. Oxygen acts as a site blocker for the adsorption, but can also stabilise NH3 to remain on the surface at higher temperatures due to electronic effects. At 300 K, it was found that both the bare and oxygen pre-covered Cu{311} surface was able to dissociate NH3 into NH2. The co-adsorption of NO and that of NH3 onto the Cu{311} surface were found to be largely independent of each other and the interaction is dominated by the displacement of NO by NH3. However, as NO adsorption on the Cu{311} surface forms O(a), it indirectly affects the adsorption of NH3 by creating an oxygen covered Cu{311} surface, which changes how NH3 adsorbs onto the surface.

In this thesis complexes of acylchalcogoureas with cadmium (II), lead (II) and nickel (II) have been synthesised and investigated as single source precursors for the formation of metal chalcogenide thin films viaaerosol assisted chemical vapour deposition (AACVD). Routes to binary thin films have been explored using homoleptic complexes of the general structure bis(N,N-diethyl-N'-naphthoylchalcogoureato)metal(II). Analysis of the thin films produced showed the successful deposition of the binary materials from the synthesised complexes when characterised by powder XRD, ICP-OES, SEM and EDX. Routes to ternary thin films with the general structure MExE'1-x, where M represents a metal (Cd, Ni and Pb); and E chalcogen (S or Se) have been investigated using heteroleptic metal complexes of cadmium, nickel or lead including different chalcogen containing N,N-diethyl-N'-naphthoylchalcogoureato ligands and diethyldithiocarbamate. The precursors were fully characterised and novel compounds had their crystal structures determined. The heteroleptic complexes were thermolysed by AACVD forming the MExE'1-x thin films. In the cases of lead, nickel and cadmium the thin films produced showed that the composition of the film tended heavily towards the metal selenide. Ternary films of type MS1-xSex was prepared by mixing their binary precursors of type bis(N,N-diethyl-N'-naphthoylselenoureato)metal(II) and bis(N,N-diethyl-N'-naphthoylthioureato)metal(II) [metal = Cd, Ni and Pb]. In the case of lead and cadmium chalcogenide films variation of the ratio of sulphur and selenium containing precursors allowed for the full transition in composition between metal sulphide and metal selenide. In the case of CdS1-xSexthe band gap of the films was determined from UV-visible spectroscopy to vary from 2.4 eV (CdS) to 1.7 eV(CdSe). In the case of NiS1-xSex the movement from sulphide to selenide was less simple with multiple phases of nickel chalcogenides produced.

Over 70% of the Earth s economically recoverable nickel (Ni) resides in laterite ore deposits, however they account for less than half of the current global nickel production. During laterization, nickel and other soluble ions are taken into solution before re-precipitating within iron oxide minerals in the limonite zone, or as serpentines and other phyllosilicates in the layers below this zone. It is these laterite deposits that show the greatest potential for low energy, environmentally conscious processing. The major host of nickel in the limonite zone is the iron-oxyhydroxide mineral goethite, α-FeOOH, where up to 4 mol% Ni has been reported in natural specimens, and even higher levels in synthetic samples (5.5 mol%). The Ni is assumed to be incorporated in the crystal structure of the goethite, but previous characterisation work only demonstrated a weak to moderate correlation of mineral structure change with the nickel content in goethite. Mining companies working on the extraction and recovery of nickel from the limonite zone of lateritic deposits have noticed that the ease with which nickel can be extracted varies greatly; goethite rich ores that appear to have similar mineralogies/geologies can display extreme variation in their leachability. It is not clear why the ores behave in this way, but in order for extraction techniques and subsequent recovery of nickel to be improved, the reasons behind this variability need to be understood. The lateritic ore materials from which nickel is extracted are generally made up of a number of different mineral phases. The multiphase nature of the samples means that characterisation of the goethite-type phases from these materials is challenging. To simplify the system and allow the association of Ni into goethite and/or other iron oxyhydroxide phases to be studied in a controlled environment, a synthetic study was carried out. Ni-bearing goethites have been synthesised at a series of different temperatures and characterised by a range of analytical techniques including PXRD, IR, Raman, TGA, ICP-OES, SEM and TEM. It was found that a second phase, ferrihydrite, co-existed with the goethites, the proportion of which increased at lower synthesis temperatures and with increasing amounts of Ni. Ferrihydrite is known to be a precursor phase in the formation of goethite, but its poorly crystalline nature makes it difficult to identify using standard characterisation techniques such as PXRD. The introduction of Ni to the system increases the stability of the ferrihydrite phase, inhibiting its transformation to goethite. It is believed that some of the Ni thought to be incorporated into goethite could actually reside in an undetected ferrihydrite phase, which could account for the differences observed in the leachability of natural materials. Characterisation techniques were investigated to try and determine a simple way to identify ferrihydrite in these systems, which could ideally be used in the field to identify the presence of ferrihydrite in goethite rich ore materials. Thermal analysis proved to be particularly promising as a technique which could be used to identify ferrihydrite rich deposits before extraction, enabling the most efficient and environmentally conscious metal recovery process for each deposit to be identified. In order to investigate the way in which Ni partitions itself between structural incorporation into goethite and association with a secondary ferrihydrite phase, a new washing technique was developed using EDTA, which is capable of selectively removing the ferrihydrite phase whilst leaving the goethite intact. This investigation suggests that a maximum of ~2.5 mol% of Ni is structurally incorporated into goethite, regardless of how much is added during the synthesis. Any excess nickel, above that which is substituted into the goethite structure, was found to be associated with the poorly crystalline ferrihydrite phase. Despite being considered a metastable phase, the increased stability of ferrihydrite resulting from the presence of Ni suggests that it may persist in laterite deposits within geological systems. If ferrihydrite is indeed present in nickeliferous laterites, it may be a significant host for Ni, and potentially many other critical elements. Based on the methodology developed whilst studying synthetic samples, a characterisation program for materials from lateritic ore deposits was conducted to investigate the presence of ferrihydrite in natural systems. From the research presented and discussed in this thesis, proof of the presence or absence of ferrihydrite in laterite systems, causing variations in the leachability of the ore materials, could not be conclusively established. The thermal analysis technique developed here successfully identified and quantified ferrihydrite in the presence of goethite in synthetic systems, and showed great potential when used to characterise the lateritic goethite samples, certainly suggesting that ferrihydrite could be present in these natural ore materials. With further refinement of the methodology, to enable a larger range of sample types to be accurately analysed, TGA is a technique which could be used as a screening tool for laterite ores.

Massive star formation takes place in the dense cores of molecular clouds where the stars may be obscured at optical wavelengths. An excellent signpost of a massive young stellar object is the presence of an ultra-compact HII region (UCHii), which is a dense photo-ionised cocoon of gas surrounding the newly formed star. The aim of this project is to develop an assembly of numerical tools, caravela, that can simulate realistic data streams representing high-mass star forming regions in our Galaxy. The synthetic output consists in images and photometric point source catalogues, in the IRAS and Herschel wavebands. In an era when large observational surveys are increasingly important, this tool can produce simulated infrared point-source catalogues of high-mass star forming regions on a Galactic scale. The approach used is to construct a synthetic Galaxy of star-forming regions represented by SED templates. The star-forming regions are distributed randomly along a four spiral arm morphology, although a wide range of geometries can be used including rings and different numbers of spiral arms. The caravela code then observes the synthetic Galaxy to produce simulated images and point source catalogues with appropriate sensitivity and angular resolution. caravela was first used to model the simulated Galaxy by constraining the synthetic output to observations made by IRAS. This numerical tool will allow the user to infer physical properties of the Galactic population of high-mass star forming regions from such observations. Second, the selected model was again observed with caravela in Herschel mode. These are therefore predictive results for the future Herschel observations. A model with 4.0×104 compact proto-stars embedded in larger grey-body envelopes (with T = 40 K and linear size scale lIII = 5.0 × 106 AU) is the best-fit model to the IRAS observational data set studied. We found a level of contamination from low- and intermediate-mass objects of " 90%. The modelled data set resulting from the Herschel simulation resulted in the detection of approximately twice as many Herschel objects than IRAS, which is consistent, in a limited way, with the real observed companion clump fraction (CCF) of 0.90 ± 0.07 (Thompson et al., 2006) means that on average there were observed 2 sources per one IRAS source. Our caravela and the real observed CCF are therefore consistent. caravela was coupled with an independent diffuse emission model (Paladini et al., 2007) and the resulting analysis is presented as an interesting seed for the future.

Processing of Si in the semiconductor and solar cell industry has been dominated by the Diode Pumped Solid State (DPSS) Ultraviolet (UV) laser. Recent advances in laser source technology have produced fibre lasers with Master Oscillator Power Amplifier (MOPA) architectures that offer high repetition rates, high operational efficiencies, and pulse modulation controls exceeding those of typical Q-switched DPSS lasers. The aim of this research is to investigate 1 μm fibre laser machining of Si with a view to identifying the influential laser parameters for optimum processing of high quality, high efficiency micro drilling and surface texturing applications. A secondary aim is to develop a greater understanding of the laser material interactions and material removal mechanism when using fast rise-time nanosecond laser pulse envelopes. The IR fibre laser was able to perform percussion drilling and single pulse machining on the polished Si over a range of intensities up to 1.22 GW/cm2. With the optimum parameters, the micro-sized holes generated by the IR laser have a well defined edge, no heavy recast and no cracks. With a pulse shape of fast rise time (<7.5 ns for a 10-90% rise in signal), a high front peak power zone (approaching 14 kW) and an energetic long tail (40-180 ns), the absorption coefficient of Si at IR wavelength increased dramatically with time and temperature due to the fact that the liquid Si has a metal like absorption behavior. As a result, Si was quickly melted and the rest of pulse energy was able to remove the liquid Si effectively. The machining process left a limited amount of resolidified melt droplets and vapor condensates, which could be washed off ultrasonically. The drilling process was energy efficient when melt expulsion dominated the machining mechanism (0.08-0.2 mJ pulse energy depending on the pulse durations). The low energy pulse (~0.2 mJ) can achieve similar depth as the high energy pulse (~0.7 mJ), so high repetition rates of 100 kHz can be used to instead of 25 kHz, resulted in high processing speed. In addition, by comparing the single pulse machining with the state of the art UV laser, the IR fibre laser machined deeper features and better surface finish in the pulse energy region of >0.07 mJ. With the pulse shaping capability, the material properties can be varied and the wavelength factor can be minimized. The results suggest that applications like microvia drilling can now be carried out with the more flexible and low cost IR fibre laser. The increased repetition rates of fibre laser can increase production speed to satisfy the needs of drilling ~10 thousands holes per second, required by the modern semiconductor and solar cell production. The shortened optical penetration length of 1 μm wavelength laser on Si with increasing temperature and sufficient thermal diffusion length resulted from the asymmetrical fibre laser pulse and the dynamic properties of Si produced a thick liquid layer. A one-dimensional heat conduction model based on the surface heating source predicted that this superheated liquid layer was able to stay above 4706 K (0.905 times the thermal critical temperature 5200 K of Si) for longer than 70 ns to induce explosive boiling. This proposed material removal mechanism was also confirmed by the shadowgraph images, showing particulates ejection lasting up to ten microseconds after the laser pulse. The estimated hole depth based on the explosive boiling alone were different from the measured ones at varying peak power densities (<1.22 GW/cm2) but fixed pulse duration (200 ns), since Si was removed by a mixture of mechanisms. With varying pulse durations (40-200 ns) but fixed peak power density (~0.63 GW/cm2), the estimated depth based on the explosive boiling was in close agreement with the measured ones (6% difference on average). The SEM images at this power density showed a micron- /submicron-sized debris field, which was also observed with the explosive boiling in the past. Although the improved quality of Si machining was demonstrated with the 1 μm MOPA based fibre laser, the setup of this system was only applicable to surface texturing, blind holes and through holes of less than 100 μm in depth. Further research is required to demonstrate the capability of more energetic pulse with higher peak power and large pulse duration range to explore more machining options.

Feynman graphs in perturbative quantum field theory are replete with infrared divergences caused by the presence of massless particles, how-ever these divergences are known to cancel order-by-order when all virtual and real contributions to a given cross section are summed and smeared against an experimental resolution. In this thesis we treat the infrared problem formally in the language of distribution theory so that we can remove the divergences with local momentum space subtractions using Hadamard's procedure. This is analogous with the BPHZ mechanism for removing UV divergences. Our aim is to show how it is possible to make both the real and virtual subtractions analytically such that we are left with manifestly finite integrands. For the virtual graphs we present a new decomposition of the integrand in momentum space and remove those terms that are divergent. For the real graphs we show how the Taylor expansion of the momentum conserving delta function allows the explicit removal of the divergent part; furthermore we show that the homogeneous properties of the soft structure greatly simplifies this procedure.

The aim of this work was to assess the suitability of vibrational spectroscopic techniques (Raman, FT-IR and FT-NIR spectroscopy) as a means for the solid-state structural analysis of pharmaceuticals. Budesonide, fluticasone propionate, salbutamol hemisulfate, terbutaline hemisulfate, ipratropium bromide, polymorphic forms of salmeterol xinafoate and two polymorphic forms of sulfathiazole were selected since they are used in the management of certain respiratory disorders and from different chemical and pharmacological entities along with some pharmaceutical excipients. Conventional visual examination is not sufficient to identify and differentiate spectra between different pharmaceuticals. To confirm the assignment of key molecular vibrational band signatures, quantum chemical calculations of the vibrational spectra were employed for better understanding of the first five selected drugs. The nondestructive nature of the vibrational spectroscopic techniques and the success of quantum chemical calculations demonstrated in this work have indeed offered a new dimension for the rapid identification and characterisation of pharmaceuticals and essentially warrant further research. The application of simultaneous in situ Raman spectroscopy and differential scanning calorimetry for the preliminary investigation of the polymorphic transformation of salmeterol xinafoate polymorphs and two polymorphic forms of sulfathiazole has also been explored in this work leading to the development of a new method for the solid-state estimation of the transition temperature of entantiotropically related pharmaceutical polymorphs which represents the first analytical record of the use of this approach for pharmaceutical polymorphs.

Ultrafast laser interaction with small nanoscale particles compose of a few atoms to no more than 10⁶ atoms have useful applications in a broad range of fields. In wakefield accelerators, the introduction of nanoparticles allows for control and improvements to resulting electron beams. Irradiation of clusters with high intensity XUV pulses allows for the study of formation and evolution of hot dense plasmas. In this work, we show the viability of the use of nanoparticles as an injection method in laser wakefield acceleration. Experiments ran on the Texas Petawatt Laser showed improvement to electron beam qualities. We were able to produce electron beam with high peak centroid energies in excess of 4 GeV, and up to 10 ± 2 GeV. In addition, low divergence electron beams were achieved along with beams with as low as 10% energy divergence. This work also explores the interaction of rare gas clusters and XUV laser pulses. We investigate the dynamics of Ne, Ar, Kr, and Xe when exposed to photons with energies around 30 eV, and 10¹³ W/cm². High charge states ions of Ne³⁺, Ar⁵⁺, Kr⁶⁺, and Xe⁸⁺ were observed. Electron kinetic energy spectra were measured and had an unexpected profiles. The relative yields of electron kinetic energies differ from the relative yields of photons irradiating the targets. The spectrum suggests there’s a greater amount of photoionization by higher energy photons than expected. The spectrum also shows that electrons below 10 eV behave differently compared to electrons with higher kinetic energies.

Synthetic lipids are of significant importance in various fields, including biosensors, drug delivery, synthetic biology, and the study of the transition from non-living matter to life. The utilization of synthetic lipids as platforms for biomimicry and catalysis is becoming increasingly popular. The molecular diversity and dynamics of synthetic lipids hold particular interest due to their relevance to the self-assembly process, the concentration of specific proteins, and their capability to host and accelerate biochemical transformations. This thesis investigates the complexity of synthetic lipid membranes from two main perspectives: the impact of molecular diversity on membrane morphology and the influence of molecular dynamics on the formation of lipid mesophases. The study examines the effects of tail and linkage groups on synthetic lipids, drawing comparisons with their biological counterparts and assessing the impact of membrane morphology on biological functions. It also investigates the interactions between synthetic lipids and surfactants, exploring how surfactants can modify membrane curvature and phase behavior. Supported by atomistic molecular dynamics simulations, the subtle patterns in hydrogen bonding and dynamics are revealed for these systems. In addition to examining synthetic lipids, this thesis introduces a novel, data-driven method for analyzing ultrafast spectra, employing dynamics modes decomposition and machine learning to improve the robustness of spectra analysis.

This thesis investigates the application. of fuzzy logic techniques and user modelling to the process of information retrieval (IR) from the World Wide Web (WWW). The research issue is whether this process can be improved through such an application. The exponential rise of information itself as an invaluable global commodity, coupled with .acceierating development in. computing and telecommunications, and boosted by networked information sources such as the WWW, has led to the development of tools, such as search engines, to facilitate information search and retrieval. However, despite their sophistication, they are unable effectively to. address users' information. needs. Also, as the-WWW can be seen as a dynamic, continuously changing global information corpus, these tools suffer from the problems of irrelevancy and redundancy. Therefore, in order to overcome these problems and remain effective, IR systems need to become 'intelligent' in some way. It is from this premise that the focus of this research has developed. Initially, theoretical and investigative research into the areas ofIR from electronic sources and the nature of the Internet (including the WWW) revealed that highly sophisticated systems are being developed and there is a drive towards the integration of, for example, electronic libraries, COROM networks, and the WWW. Research into intelligent IR, the use of AI techniques to improve the IR process, informed an evaluation of various approaches. This revealed that a munber of techniques, for example, expert systems, neural networks and semantic networks, have been employed, with limited success. Owing to the nature of the WWW, though, many of the previous AI approaches are inapplicable as they rely too much on extensive knowledge of the retrieval corpus. However, the evaluation suggested that fuzzy logic, with its inherent ability to capture partial knowledge within fuzzy sets, is a valid approach. User modelling research indicated that adaptive user stereotypes are a fruitful way to represent different types of user and their information need. Here, these stereotypes are represented as fuzzy sets, ensuring flexibility and adaptivity. The goal of the reported research. then, was not to. develop an 'intelligent agent' but to apply fuzzy logic techniques and user modelling to the process of user query formulation, in order to test the research issue. This issue was whether the application of these techniques could improve the IR process. A prototype system, the Fuzzy Modelling Query Assistant (FMQA), was developed that attempts intelligently to assist the user in capturing their information need. The concept was to refine the user's query before submitting it to an existing search engine, in order to improve upon the IR results of using the search tool alone. To address the research issue, a user study of the FMQA was performed. The design and conduct is reported in depth. The study results were analysed and the findings are given. The results indicate that,. for certain types of user especially, the FMQA does provide improvement in the IR process, in terms of the results. There is a critical review of the research aims in the light of the results, conclusions are drawn and recommendations for future research given.

Due to their networked structure, metal organic frameworks (MOFs) are commercially used to adsorb various gases, liquids, or ions at their metal nodes or sequester the same within their pores. That MOFs are porous, extended solids can make performing density functional theory (DFT) calculations to optimize and explore their electronic and spatial properties complicated. Herein, I will discuss various ways DFT calculations can simplify the investigation of MOF material properties, with specific reference to three MOF systems. The first system is the phosphine-pillared, Co- and Os-containing MOF, Os₂-PCM-201, and its analogue, the arsine-pillared MOF, Os₂-ACM-201. The second is the Cu-containing MOF HKUST-1, which is linked together by 1,3,5- benzenetricarboxylate. The third is the stibine-pillared, Co- and Ag- containing MOF, Ag-SbCM-201. That MOFs are extended solids means that DFT programs that employ periodic boundary conditions must be used unless one is modeling nodes of interest with molecular analogues. The calculation of binding energies and frequencies of vibration (IR modes) are the major topics to be discussed.

Long wave infrared (LWIR) optics that transmit in the 8 to 14 m wavelength range and, additionally, can withstand severe physical and thermal stresses are needed for advanced remote sensing, guidance and communication-based applications. However, most non-oxide transparent LWIR optics do not have the wider transmission range, nor the hardness and resistance to thermal shock needed for extreme environments. Because of these limitations, research is circling back to a promising material, calcium lanthanum sulfide (CLS), that could meet LWIR needs for extreme environments. In this thesis, we will demonstrate the abilities of x-ray photoelectron spectroscopy (XPS) as a technique for characterizing CLS powders and ceramics for elemental analysis, valence state and stoichiometry evaluation. Three preliminary studies were conducted - a binary metal sulfide evaluation of lanthanum sulfide (La2S3) and calcium sulfide (CaS), and a calibration curve of mixtures of the two binary metal sulfide powders from a known concentration matrix. Based on these results, a methodology was developed to evaluate CLS powder and ceramics via XPS. We showcase the power of XPS to reliably determine CLS stoichiometry, identify impurities and defects as related to the presence of carbon and oxygen during processing, and predict the bonding environment of sulfur which can lead to better quality CLS ceramics. This thesis demonstrates the use of XPS as a potential characterization tool in CLS to identify contaminants, determine if stoichiometry is met, and identify the bonding environments to assist in processing improvements for producing higher-quality ceramics.

Novel modifications of styrene-butadiene rubber were studied using conventional curatives, sulfur curing packages or peroxides, to efficiently utilize supramolecular reinforcement strategies that improve the mechanical properties of rubber. Thiol-ene coupling proved to be an effective method for modifying styrene-butadiene rubber during peroxide curing, but it was inadequate when attempted during sulfur vulcanization.Supramolecular reinforcement was achieved by grafting mercapto-functionalized sodium phosphate esters to styrene-butadiene rubber during peroxide curing which electrostatically associate. The association strength between these ionic grafts played a critical role in determining the degree of reinforcement. Possible mechanisms by which reinforcement occurs were discussed and, at low grafting densities, at least one mechanism was determined not to play a major role. It was shown that substantial modification of cis-1,4-polyisoprene does not occur by thiol-ene coupling and that another chemical means must be used to modify this substrate.Reagents consisting of thioaldehydes derived from thiosulfinates were used in Alder-ene reactions to modify cis-1,4-polyisoprene. Based on this chemistry, new grafting and crosslinking agents were developed that react quickly and at relatively low temperatures. Important elements in the molecular design of these curatives were discussed and it was demonstrated that good mechanical properties are attainable.

Image compression algorithms are the basis of media transmission and compression in the field of image processing. Decades after their inception, algorithms such as the JPEG image codec continue to be the industry standard. A notable research topic gathering momentum in the field of compression is deep learning (DL). This paper explores the opti- mization of DL models for ideal image compression and object detection (OD) applications.The DL model to be optimized is based upon an existing compression framework known as the CONNECT model. This framework wraps the traditional JPEG image codec within two convolutional neural networks (CNNs). The first network, ComCNN, focuses on com- pressing an input image into a compact representation to be fed into the image codec. The second network, RecCNN, focuses on reconstructing the output image from the codec as similarly as possible to the original image. To enhance the performance of the CONNECT model, an optimization software called Optuna wraps the framework. Hyperparameters are selected from each CNN to be evaluated and optimized by Optuna. Once the CONNECT model produces ideal results, the output images are applied to the YOLOv5 OD network.This paper explores the impact of DL hyperparameters on image quality and compres- sion metrics. In addition, a detection network will provide context to the effect of image compression on computer vision applications.

Abstract: Many software engineering problems have traditionally been approached by applying techniques based on static analysis and fixed sets of rules. I created two novel techniques to tackle three software engineering problems: typo location, fix suggestion, and crash report bucket creation. However, unlike previous techniques based on static analysis or a fixed set of rules, these techniques are based on methods commonly used to handle natural language artifacts. Existing tools and previous work typically tries to be general and work with any valid program or theoretically possible output. In contrast, this thesis builds upon the success of prior work that successfully applied NLP models to code to improve code completion in an IDE (Integrated Development Environment). This thesis continues in that vein and presents tools that focus on the code that programmers actually write and the crashes that actually occur. First, I applied natural-language models to locate errors in source code that cause the code to fail to compile or create an error when the code runs. Language models can adapt to coding styles and idioms. My co-authors and I showed that a tool using an n-gram model of code previously compiled successfully could supplement errors with locations produced by the Java compiler. Using our tool to suggest a location after each error message produced by the Java compiler resulted in an MRR score 11-40% closer to a perfect score than the Java compiler's score. Then, my co-authors and I showed that a similar approach also worked with the Python interpreter, though it faced significantly more challenges. When combined with the Python interpreter's error messages, our approach correctly located an additional 9-23% of tested typos made by mutation. Next, my co-authors and I showed that the technique still worked in a more restricted offline setting. In addition, we showed that the approach could also accurately suggest changes to repair around a third of typos made by students. I also applied the TF-IDF representation and distance function to the task of bucketing (clustering) software crash reports. In all cases, performance (in terms of F1-score) matched or beat commonly used rule-based techniques. The TF-IDF-driven approach can adapt automatically to patterns in crash reports as they evolve. Additionally, several side benefits arose from using statistical techniques.Some errors in source code can be automatically repaired using a language model. Patterns in crash metadata can be extracted easily using a bag-of-words approach with a suitable tokenizer. This thesis’s results encourage research on approaches based on on-line off-the-shelf algorithms or models initially developed for natural-language artifacts with programming language and other software artifacts. However, this thesis’s results do not necessarily guarantee that such uses will be successful; it does indicate that they should, at least, be considered.

Polycystic ovarian syndrome (PCOS) is a reproductive and endocrine disorder in women of childbearing age. This disorder includes multiple clinical manifestations, namely insulin resistance (IR) and infertility related to hormonal imbalances and anovulation. Despite being a common condition, its etiology and treatment modalities remain poorly defined. Without proper understanding and management of the condition, women may suffer numerous complications besides infertility such as diabetes mellitus type II (DMII), endometrial cancer, and cardiovascular disease. Therefore, further research is critical. This integrative review will create a comprehensive understanding of PCOS' pathophysiology, potential complications, treatment methods, and nursing considerations to promote the health and well-being of women affected by this condition.

ABSTRACT AEROSOL SAMPLING STRATEGY: Effect of Particle Transfer to Sampler Covers and Estimation of Conversion Factors between the United States and German Methods for Quartz sampling GODWIN A. EREKAIFE In many countries, communities of experts, including industrial hygienists, have developed unique sampling strategies to determine workers’ exposure to aerosolized particles (e.g., metals, wood dust etc.). However, using different sampling and analytical methods for the same chemical often results in different exposure levels for a similar exposure group (SEG). The exposure discrepancies among different countries that are caused by using different measurement strategies are not always systematically defined. Therefore, this study investigates aerosol sampling strategies in two parts: 1) the potential for particle loss to the sampler covers during sample transportation to improve sampling methodology and prevent underestimation of mass concentrations (Chapter 2) and 2) determining the relationship between exposure measurements of respirable crystalline silica (RCS) using the U.S. measurement strategy (NIOSH method) and the German strategy (IFA method), and to develop a conversion factor (or equation) to adjust for differences (Chapter 3). Below is a result summary of the investigation. Effects of particle transfer to the covers of aerosol samplers during transportation: Wood dust samples were collected in a sanding chamber using four different samplers: closed-face cassettes (CFC), CFC with Accu-CAP™ inserts, disposable inhalable samplers (DIS), and Institute of Occupational Medicine (IOM). Welding fumes were collected in a walk-in chamber using the same samplers, with Solu-Sert™ replacing Accu-CAP. The samples were divided into two groups, with one group transported by air and the other by land. They were returned in the same manner and analyzed gravimetrically for wood dust and chemically for welding fumes. For wood dust, IOM showed a significantly higher percentage of particles transferred to the covers compared with the other samplers regardless of the transportation mode, while other samplers did not. For the welding fumes samples, most samples showed nondetectable amounts of the analyte on the covers. Overall, this study confirms that particle transfer to sampler covers during transport highly depends upon the transportation mode, particle size ranges, and the sampler type for wood dust, whereas particle transfer seems minimal for welding fumes. Although the findings of this study are based on two materials and limited sample sizes, occupational professionals should account for this transfer when handling and analyzing samples in practice. Estimation of conversion factors between the United States and German methods for quartz sampling: This study compared the sampling and analytical methods of each country to determine RCS exposures in three ways: 1) spiked sample analysis, to verify the differences between both countries’ analytical methods, 2) environmental chamber study, where side-by-side samples were collected under environmentally controlled conditions to determine the differences of samplers along with the analytical difference, and 3) field study, to determine the impact of uncontrolled environmental conditions and unknown workplace characteristics on the results by each method. Overall, differences between the two country’s methods were observed and the calculated conversion factor was 0.71 when converting RCS concentrations from GK2.69 to FSP-10 cyclones using infrared spectroscopy (IR). The findings of this study will fill the knowledge gap associated with exposure discrepancies between two countries that are caused by using different measurement strategies. Most importantly, by using the outputs of this study, larger databases can be created from several smaller repositories of existing data and can be exploited to determine long-term exposure trends and evaluate exposure control methods. Finally, the application of the findings would not be limited to just these two countries but can extend to other countries that have adopted either NIOSH or IFA methods.

Myocardial ischemia reperfusion (IR) injury has been shown to cause mitochondrial dysfunction. The electron transport chain (ETC) is a major source of superoxide and other superoxide derived reactive oxygen species during ischemia and reperfusion. Previous studies suggest that the downregulation of ETC, Krebs cycle, and antioxidant enzymes in the mitochondria occur as a result of increased oxidative stress. SOD2 is one of the primary antioxidants in the mitochondrial matrix. It is capable of scavenging superoxide into hydrogen peroxide. To test the therapeutic potential of increased superoxide scavenging in murine models, we subjected cardiac specific human SOD2 overexpressing (SOD2TG) murine hearts to 30 minutes of ischemia and 45 minutes of reperfusion using the Langendorff isolated heart system. SOD2TG hearts were relatively protected from impairment of electron transport activity in complex I-IV as well as downregulation of Krebs cycle enzyme activities. However, SOD2 overexpressing hearts had selectively decreased basal respiratory enzyme kinetics without indication of impairment of respiratory coupling and hydrogen peroxide scavenging.

The progesterone receptor membrane component 1 (PGRMC1) is a multifunctional protein with a heme-binding domain that promotes cellular signaling via receptor trafficking, and is essential for some elements of tumor growth and metastasis. PGRMC1 is upregulated in breast, colon, lung and thyroid tumors. We expanded the analysis of PGRMC1 in the clinical setting, and report the first analysis of PGRMC1 in human oral cavity and ovarian tumors and found PGRMC1 to correlate with lung and ovarian cancer patient survival. Furthermore, we discovered a specific role for PGRMC1 in cancer stem cell viability. PGRMC1 directly associates with the epidermal growth factor (EGFR) in cancer cells, and we reviewed multiple signaling-associated pathways that are important in trafficking wild-type and mutant EGFR. To better understand the potential of PGRMC1 in receptor tyrosine kinase trafficking, we extended our research to the insulin receptor (IR). Changes in insulin signaling have been linked to multiple diseases, because IR plays a key role in glucose metabolism, cellular survival and proliferation. We found PGRMC1 to co-precipitate with IR in cancer cells and in an adipose model system. PGRMC1 increased IR plasma membrane levels in multiple cancer cell lines, and was also found to increase plasma membrane levels of two glucose transporters. Treatment with a PGRMC1 ligand significantly increased IR levels in human adipocytes. Moreover, we demonstrate that both insulin binding and glucose uptake are dependent on PGRMC1.

Using and sponsoring militant groups as proxies to meet geostrategic interests is an old political phenomenon. IR research indicates that state’s sponsor militant groups to increase their regional influence, destabilize regional rivals, export political ideology, maintain economic stability, preserve plausible deniability, and deter a more powerful rival. Yet, none of these motivations adequately explain the institutional foundations and the role of a state’s national identity in sponsorship. In this dissertation I present a theory for continued state-sponsorship, arguing that sponsorship of militant groups is linked to its ontological security, which refers to the security acquired by having a stable, consistent identity. I argue that sponsorship of militancy satisfies the state’s need of having a stable and consistent identity, and ultimately increases ontological security. How a state obtains and maintains its ontological security is deeply tied to its ability to achieve its geostrategic interests. To better understand how sponsorship of militant groups functions as a means to increase the state’s ontological security, I specify the institutional foundations and requirements for maintaining a state’s ontological security, and ask: Does a state’s sponsorship of militancy have the same or different effects on its territorial security versus its ontological security? What are the processes of ontological security? What is the role of civil institutions in the processes of ontological security? And how do civil institutions facilitate state-sponsorship of militant groups? I use Pakistan to illustrate the value of this approach and investigate how its civil institutions help legitimize the state’s policy of sponsorship as a means to enhance the state’s ontological security. Employing a reflexive approach and an ontological security framework to the study of state-sponsorship yields several important findings for IR theory, mainstream and critical security studies, and interdisciplinary approaches to studying militancy. First, my research emphasizes that while its external environment influences a state’s identity, it is nonetheless created internally by the interaction of its civil and military institutions. Second, disaggregating the state allows us to better understand how “security” is created and how closely “security” is intertwined with “identity” and “national interests.” Unpacking the state, therefore, adds more theoretical and empirical value to IR theory. Finally, by revealing the contributions of the Pakistani state’s civil institutions in the state’s policy of sponsoring militant groups, this dissertation disrupts the conventional understanding of Pakistan’s institutions, which has mainly considered the military as the primary institution involved in the sponsorship of militant groups. My dissertation highlights how this conventional view is incomplete and needs to be reexamined.

While computational chemistry methods have a wide range of applications within the set of traditional physical sciences, very little is being done in terms of expanding their usage into other areas of science where these methods can help clarify research questions. One such promising field is Forensic Science, where detailed, rapidly acquired sets of chemical data can help in decision-making at a crime scene. As part of an effort to create a database that fits these characteristics, the present work makes use of computational chemistry methods to increase the information readily available for the rapid identification and scheduling of drugs to the forensic scientist. Ab initio geometry optimizations, vibrational spectra calculations and ESI-MS fragmentation prediction of a group of common psychedelics are here presented. In addition, we describe an under development graphical user interface to perform ab initio calculations using the GAMESS software package in a more accessible manner. Results show that the set of theoretical techniques here utilized, closely approximate experimental data. Another aspect covered in this work is the implementation of a boiling point estimation method based on group contributions to generate chemical dispersion areas with the ALOHA software package. Once again, theoretical results showed to be in agreement with experimental boiling point values. A computer program written to facilitate the execution of the boiling point estimation method is also shown.

The organization of two or more biological macromolecules into a functioning assembly is critical for many biological functions to occur. This phenomenon is the result of subtle interplay between complimentary structural and electrostatic factors. While a growing protein data bank of solved protein structures provides experimental evidence for studying the structural factors that stabilize protein-protein interface, there has been little advance in experimental determination of the electrostatic contributions. This lack of experimental investigation into protein electrostatics results in an inability to describe or predict how protein-protein complexes are arranged and stabilized. This problem is addressed in this dissertation by use of vibrational Stark effect (VSE) spectroscopy in which the spectral transitions of a vibrational probe are directly related to the strength and direction of the electric fields in the vicinity of the probe. The work presented here details an approach using VSE spectroscopy coupled with molecular dynamics simulation (MD) to interpret the role that electrostatics play in organizing the signaling protein Ras' interactions with its downstream effectors Raf and Ral guanosine dissociation simulator (RalGDS). Each chapter describes a specific set of experiments and MD simulations designed to understand the nature of protein-protein interactions. In Chapter 3, changes in the absorption energy of the nitrile probe at nine positions along the Ras-Ral interface were compared to results of a previous study examining this interface with Ral-based probes, and a pattern of low electrostatic field in the core of the interface surrounded by a ring of high electrostatic field around the perimeter of the interface was found. The areas of conserved Stark shifts are used to help describe electrostatic factors that stabilize the Ras-Ral interface. In Chapter 4, VSE is used to describe an electrostatic origin to the binding tilt between complexes formed between Ras and its two effectors Raf and Ral. There are three regions of conserved Stark effect shifts upon docking with WT Ras between the two effectors, indicating that the docked complexes conserve electrostatic fields, resulting in different binding orientation of otherwise structurally similar proteins. Chapter 5 details the use of MD simulation in correlation with VSE data for 18 mutants of the Ras at the oncogenic position 61 site. The combination of experimental and simulations support the hypothesis that position 61 on Ras is used to coordinate an active site water molecule during native guanosine triphosphate (GTP) hydrolysis.

Organic photoactive molecules and polymers are gaining much attention due to their potential applications in organic photovoltaic devices and organic electronics. Organic photovoltaic devices suffer from low efficiencies that result from low charge carrier mobilities and short exciton diffusion lengths. To increase the efficiency of organic photovoltaic devices, much of the focus of current research in this field is on panchromic organic molecules, suitable donor-acceptor molecules and self-organized organic semiconductors. Controllable nano-morphologies of donor and acceptor molecules via self-assembly, together with structured interfaces which are important for efficient charge separation and transport, may reduce the problems and yield photovoltaics with much higher efficiencies. Porphyrins are stable, largely planar, aromatic macrocycles, which makes them excellent at forming aggregates by way of pp-interactions. Their aromatic structures and resulting favorable redox and excited state properties, in turn, make them excellent model compounds for the study of photo-induced processes. N-Confused porphyrins are structural isomers of porphyrins which show physical and chemical properties different than that of regular porphyrins. N-Confused porphyrins are interesting molecules due to their structure, reactivity, solvent dependent tautomerization and metal binding properties. This dissertation presents synthetic methods to design new derivatives of porphyrins and N-confused porphyrins to obtain new photophysical properties as well as incorporate these molecules into self-assembled nano-morphologies. Several forms of intermolecular interactions are used in non-covalent syntheses and self assembly, most prominently hydrogen bonding and p-stacking interactions. Porphyrins substituted with peripheral polyalkyl chains have been shown to have liquid crystal properties and usually form columnar mesophases within certain temperature ranges. In the first project of this dissertation, several meso-subtituted tetraarylporphyrins have been synthesized, where the porphyrin macrocycle is attached using different types of linkages to a phenyl ring bearing trialkoxy groups. The effect of the linker in aggregations of these porphyrins via peripheral interactions, such as through the formation of hydrogen bonds and dipole interactions, between porphyrins is presented. The morphology of these porphyrins in drop cast thin films, as well as their aggregation behavior in solution, as a function of the combined p-stacking and H-bonding properties is also presented in this dissertation. Porphyrins with ester, hydrazide and ethylenediamide (EDA) linking groups between the porphyrin macrocycle and the trialkoxy aryl groups were observed to self-assemble in solution and in thin films. TEM studies of these porphyrins revealed nano-fiber formation from methylcyclohexane (MCH) and chloroform solutions. In the second portion of this dissertation a series of asymmetrically substituted N-confused porphyrins were synthesized using N-confused and regular dipyrromethanes. The structures of these compounds were confirmed by various 2D NMR techniques. This project represents the first synthesis of asymmetrically substituted N-confused tetraarylporphyrins. In a third project, a series of tetrasubstituted N-confused porphyrins having different linking groups between the N-confused porphyrin macrocyle and trialkoxyaryl groups were synthesized. The photophysical properties and morphologies of these meso-substituted N-confused tetraarylporphyrins (NCTArPs) are described. These molecules were found to assemble into nano-fibers and nano-rods, most likely because of H-bonding interactions between the NCPs. This work represents the first report on NCPs self-assembly into arrays. Finally, NCPs were shown to undergo reaction with nitromethane to produce nitromethane substituted NCPs which have very different photophysical properties from NCPs.

Femtosecond Laser Direct Writing (FLDW) is a viable technique for producing photonic devices in bulk materials. This novel manufacturing technique is versatile due to its full 3D fabrication capability. Typically, the only requirement for this process is that the base material must be transparent to the laser wavelength. The modification process itself is based on non-linear energy absorption of laser light within the focal volume of the incident beam. This thesis addresses the feasibility of this technique for introducing photonic structures into novel dielectric materials. Additionally, this work provides a deeper understanding of the lightmatter interaction mechanism occurring at high pulse repetition rates. A novel structure on the sample surface in the form of nano-fibers was observed when the bulk material was irradiated with high repetition rate pulse trains. To utilize the advantages of the FLDW technique even further, a transfer of the technology from dielectric to semiconductor materials is investigated. However, this demands detailed insight of the absorption and modification processes themselves. Experiments and the results suggested that non-linear absorption, specifically avalanche ionization, is the limiting factor inhibiting the application of FLDW to bulk semiconductors with today’s laser sources.

Research conducted at Lincoln University, New Zealand, evaluated an alternative use for recycled glass in its crushed form as a mulch under grapevines. The trial comprised four treatments: clear glass, brown glass, mixed glass (which is primarily green and brown) and undisturbed soil as a control, with four replicates in a randomised block design. The vine material was twelve year-old Pinot noir 777 on 3309 rootstock. Radiation reflected back up into the fruiting zone was quantified using a Bentham spectroradiometer under clear and sunny field conditions. Reflection from the mulches was also measured under controlled conditions. The results showed that clear glass reflected the highest amount of radiation in all the spectral ranges evaluated. UV-B radiation reflected by clear glass was double that reflected by the control. UV-A reflected by clear glass was about seven times more than that of the undisturbed soil treatment. Readings for PAR were almost five times larger than the control and, for infra-red (IR), this difference was twice as much as for the control. PAR was also divided in different “colours”, with clear glass being the most reflective treatment in all PAR ranges. Similar data were obtained from the evaluation of the mulches under controlled conditions. However, the extra amounts of radiation reflected by the mulches did not have any effect on havest parameters: number of clusters, cluster weight, potential crop, ºBrix, pH or TA. Aromatic profiles of the juice obtained from the grapes of this trial were evaluated using GC-O analysis. The panellist identified seven aroma descriptors from the samples: cut grass, mushroom, fresh peas, violet, cooked potato, rose and blackberry. Despite more aromas being detected, these were the ones most frequently sniffed by the panellist. The descriptors corresponded only to an association between panellist’s perception and a known aroma. The use of reflective mulches showed an influence on the aromatic profile of the grape. Clear glass decreased the intensity of the cooked potato-like aroma. This treatment also enhanced the aromas described as roses and blackberry when sniffed by the panellist. GC-MS and a mix of standards were used to determine the compounds related to each of the aromas described by the panellist. Hexanal was reported as the compound related to the aroma described as cut grass, and 1-hexanol was related to the aroma described as fresh peas. The rest of the descriptors were only tentatively identified. To do that, the retention time of each descriptor was compared with an alkane mix of standards and information registered in the literature. For mushroom aroma, 2-octanone was described as the most possible compound related to this aroma in the samples analysed. The aroma described as violet was associated to four different compounds: (Z)-linalool oxide, (E)-linalool oxide, nerol oxide and linalool oxide. The cooked potato-like aroma was related to methional, which was described for the first time in this experiment on Pinot noir juice. Linalool was associated with the aroma described as rose by the panellist, and β-ionone was related with the blackberry-like aroma.

The current trend in embedded systems design is to move the initial design and exploration phase to a higher level of abstraction, in order to tackle the rapidly increasing complexity of embedded systems. One approach of abstracting software development from the low level platform details is host- compiled simulation. Characteristics of the target platform are represented in a host-compiled simulation model by annotating the high level source code. Compiler optimizations make accurate annotation of the code a challenging task. In this thesis, we describe an approach to enable correct back-annotation of C code at the basic block level, while taking compiler optimizations into account.

Square nickel mesh perforated with micron scale holes exhibits extraordinary transmission due to propagating surface plasmon polaritions (PSPP) combined with cavity modes. Propagating surface plasmon resonances are known to disperse with the angle of incident light and such experiments yield rich information regarding the plasmonics of the material. More accurate polarized Gamma X dispersion is presented within, as well as the first polarized Gamma M dispersion of square nickel mesh. Calculation of resonance positions within these experiments predicts an effective index of refraction for the asymmetric coupled surface plasmon polaritons to have a value of n’eff = 1.043. Gamma P and Gamma Q dispersion of hexagonal mesh is presented and the coupling of asymmetric plasmonic surfaces examined. Calculations allowing interactions between PSPP states of square mesh are compared with experimental results and traditional predictions of mesh, PSPP transmission maxima; explaining variation from experimental results and traditional predictions and illustrating the polariton, or mixed state, nature of PSPPs. Lastly, scatter free infrared spectra of sixty-three individual micron scale dust particles are presented by placement of each particle in a hole of plasmonic square nickel mesh. The constituents of each particle and the process of quantification of materials is examined by use of Mie scattering, Lorentz dispersion, and Bruggeman effective medium theories. The propagation lengths for PSPP resonances on such mesh are poor (~1-2 hole-to-hole spacings), compared to smooth metal predictions or less absorbing metals, making this mesh ideal for studying individual particles. The PSPPs funnel light through the particles, but they are effectively isolated so long as the neighboring holes are empty. Saturation of absorption peaks at this scale are demonstrated.

Dilithium phthalocyanine (Li2Pc) consists of an aromatic macrocyclepossessing a doubly negative charge and two Li+ counterions. One Li+ ion is easilydisplaceable while the other remains coordinated to the phthalocyanine ring. Thedisplaceable Li+ cation can be exchanged with other cations, such as a singly chargedtetra-alkyl ammonium cation, by using several variations of a general procedure. It hasbeen demonstrated that tetraalkylammonium lithium phthalocyanines (TAA-LiPcs) canbe successfully and reproducibly synthesized with yields ranging from 54.5% up to64.3%. All TAA-LiPcs demonstrated poor solubilities from approximately 370.4°C to157.9°C and depended greatly upon the alkyl-chain length of the exchanged cation.

Among fiber-based lasers, the availability of high energy and high peak-power pulsed sources is of critical importance for a variety of application ranging from remote sensing, material processing to laser-plasma EUV generation. For most of the applications, high average-power is required in preferably diffraction-limited beams. In this dissertation, we demonstrate usage of very large-mode-area (LMA) fibers to significantly exceed fundamental pulse energy and peak-power limitations of standard single-mode fibers and explore the limit of core size scaling in LMA fibers. We show systematic studies in both theoretical modeling and experimental characterization of beam quality control in extremely large core LMA fibers, including coiling induced higher-order-mode filtering effect in low numerical aperture (NA) Yb-doped fiber amplifiers and fundamental mode excitation in high NA Er-doped fiber amplifiers. We report achieving good beam qualities (M2∼1.3) in 80-mum Yb-doped and 70-mum Er-doped fiber amplifiers, corresponding to the largest mode diameters of conventional step-index LMA fibers with nearly diffraction-limited output for applications at ∼1-mum and ∼1.55mum wavelengths, respectively. Large core size ensures higher energy extraction and increases thresholds for the onset of optical damage and detrimental nonlinear effects. We demonstrate in this work that millijoule energies and megawatt peak-powers in nanosecond pulses can be achieved in nearly diffraction-limited beam using 80-mum core Yb-doped fiber amplifier, and also show the average-power scalability of this pulsed fiber laser up to 85-W. Comparable pulse energies and peak-powers are believed to be achievable in 70-mum core Er-doped fiber amplifier for applications at ∼1.55-mum wavelength. Here, we report demonstration of average-power scaling of nanosecond and ultrashort pulsed fiber lasers using 25-mum core Er/Yb co-doped fiber amplifier. In particular, high average-power (∼28-W) ultrashort (∼1.4-ps) pulsed fiber laser was realized in fiber-based chirped pulse amplification (FCPA) system using novel chirped volume Bragg grating (CVBG) pulse stretchers/compressors. These results indicate that fiber laser technology has significant potential of replacing conventional pulsed solid-state lasers and is a better alternative for applications that require high average-powers.

Quantitative analysis in infrared microscopy was studied. Various physical phenomena, caused by sample structure, refractive index differences, and angles of incidence were investigated. Such phenomena include diffraction and refraction, which introduce spectral artifacts that can limit quantitative infrared microspectroscopy. The address the limiting phenomena, improvements in microscope design and the optimum use of sampling accessories were sought. Thus, a newly developed imaging detector was used along with an attenuated total reflectance (ATR accessory, providing sub-wavelength spatial resolution, on the order of 4 micrometers. Moreover, smaller samples were interrogated without obvious spectral artifacts due to sample structure. In addition, a specially-designed macro ATR accessory was created for the collection of spectral images from surfaces of hard-to-prepare samples, which included living tissue and a biological sample. Finally, the use of ATR and Raman spectroscopy was successfully applied, laying the groundwork for development of a combined Raman/Infrared ATR microscope.

A quantitative evaluation of a self-emitting far IR scene simulator is performed. The simulation system is comprised of a white-light source, spatial light modulator, optics, and a visible-to-infrared transducer. The performance was evaluated by measuring the MTFs of the system and sub-components and the thermal contrast. An attempt to correct variations in the radiometric response across the scene is done by modifying pixel values. Additionally, the effect of cooling the infrared transducer on the thermal contrast is investigated. Results are compared to a previous system which used a coherent light source.