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Rhombohedral graphite thin films, or ABC stacked multilayer graphene systems had been attracting a lot of theoretical interest due to their predicted extremely flat bands in the low energy limit which were in principle susceptible to various many body interactions such as magnetism and superconductivity. However, due to the competing Bernal hexagonal phase being more energetically favourable, experimental investigations into rhombohedral stacked graphite films had been limited. Despite the recent breakthrough in identification of rhombohedral domains in exfoliated graphite films, the electron transport investigation into rhombohedral graphite films were carried out up to tetra-layer systems. This thesis reports the first experiments that systematically characterises rhombohedral graphite films up to 50 layers encapsulated by high quality hBN crystals. We find that, at high temperatures (above 50K) conduction properties of rhombohedral graphite films are dominated by thermal activation across the bulk gap resembling an intrinsic semiconductor. At lower temperatures however, a semiconductor-metal transition manifests itself with conduction across the metallic surfaces dominating transport properties, thus enabling the electron transport investigation of low energy flat bands. Through Landau level spectroscopy, we find that low energy band structure undergoes a trigonal warping as well as a modified dispersion. The low energy bands become not as flat as originally predicted having a E = p2 dispersion with a Berry phase of NPi. We find that, on samples with 9-12 layer thickness, an interaction induced gap opens at the charge neutrality point accompanied by Berry curvature. Magnetic field characterisation of the gap as well as its hysteretic behaviour suggests possible magnetisation accompanied by the gap opening. We also find that, as predicted theoretically, above a finite displacement field which overcomes the screening ability of surface charges of rhombohedral graphite films, a band gap opens, with this gap opening being absent on samples with stacking faults. Lastly, we study the transport properties of bulk charges, demonstrating a thickness (bulk-carrier density) dependent cross-over from three dimensional weak-antilocalization to weak-localization. We also show that, there is a finite Lorentz force induced displacement field generation on rhombohedral graphite when an in-plane magnetic field is applied perpendicular to current.

Mindsets have been gaining popularity recently in the field of second language acquisition (SLA). There have been studies exploring language mindsets in relation to emotions such as anxiety and fear of failure (e.g., Lou & Noels, 2017), anxiety, rejection sensitivity, contact avoidance, and willingness to interact (e.g., Lou & Noels, 2020a), language anxiety, use of language, and reported language proficiency (e.g., Lou & Noels, 2020b), anxiety and confidence (e.g., Ozdemir & Papi, 2021), and L2 grit (e.g., Khajavy, et al., 2020; Teimouri, et al., 2022). Although these studies help scholars to understand the relationship between mindsets and emotions, there is a gap in the literature of SLA in terms of language mindsets intervention. There are only a few studies implementing an intervention to change students' language mindsets in the field of psychology (e.g., Lou & Noels, 2016, 2020a). In order to fill in the gap of the lack of intervention studies in the field of SLA, the current study implemented a language mindset intervention with international graduate students to change their fixed language mindsets to growth language mindsets. For this purpose, 108 participants were recruited for Phase 1 of the study. Out of 108 participants, 61 of them were eligible to take part in Phase 2. However, 60 participants' data were analyzed because 1 participant wanted to skip the writing part, which was part of the intervention and the manipulation check. Out of 60 participants, 57 of them were willing to participate in Phase 3. The results revealed that fixed language mindset predicted L2 speaking anxiety, whereas growth language mindset was a predictor of L2 enjoyment. There was a significant change in language speaking performance for the growth language mindset condition in terms of lexical and syntactic errors and fillers. The use of errors and fillers decreased in the growth language mindset condition. On the other hand, there was an increase in lexical diversity in the fixed language mindset condition. Theoretical and educational implications will be discussed. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Polymethyl methacrylate (PMMA) bone cements have been used for stabilizing bone prostheses and filling cavities due to their suitable mechanical properties. PMMA bone cements, with and without addition of magnetic glass-ceramic (MGC), have been recently investigated for the treatment of bone cancer. The addition of MGC to PMMA bone cements allows for the treatment of cancer via magnetic induction hyperthermia. This PhD thesis focused on the potential of MGC addition to commercial dental and orthopaedic PMMA cements for bone cancer treatment. MGC was prepared by melt-quenching technique at 1550°C. It contained a crystalline magnetic phase embedded in the glass matrix. MGC was mixed with dental and orthopaedic PMMA cements in amounts up to 40%. A method for production of magnetic PMMA cements (MPCs) with high reproducibility and dimensional accuracy was developed. The mechanical properties, in vitro bioactivity, cytotoxicity and heat generation of the resulted MPCswere evaluated. Compressive strength and four-point bending tests on MPCs were performed using the ISO 5833:2002 standard. The magnetic cements containing up to 30% MGC met the ISO 5833:2002 standard requirements. In vitro bioactivity was tested in a simulated body fluid (SBF). Apatite crystals started to form on the surface of MPCs after 2 weeks of immersion in SBF, showing the bioactive properties of these MPCs. Although cytotoxicity test results were found inconclusive, there was a decrease in the cell viability with addition of MGC in the bone cement. Preliminary induction heating tests showed that all MPC samples could be heated to a similar temperature range in 5 minutes using magnetic fields compatible with operating rooms in hospitals. The thermal, mechanical and biological properties of MPCs, analysed during this PhD thesis, showed that MPCs are promising biomaterials for the treatment of bone cancer using magnetic induction hyperthermia.

The Armenian communities living outside of historical Armenia have long been considered as constituting the Armenian diaspora (Spyurk). After the collapse of the Soviet Union and Armenia's achievement of independence, there has emerged a new form of Armenian migration, as members of the Armenian nation state (hayastantsis) began to emigrate and join with their historical diasporic communities (spiurkahays). This thesis aims to examine the implications of this encounter for hayastantsis living in Los Angeles, California in relation to three particular themes: 1) emigrants' identities and homeland imaginations; 2) their senses of belonging and immigrant transnationalism; and 3) co-ethnic relations between hayastantsis and spiurkahays. The main empirical aim of this thesis is to generate new understanding of the lives, experiences and identities of Soviet and post-Soviet Armenian emigrants from Armenia (also referred to as SOPSAM in this thesis) who had been exposed to different geographical, historical and material processes than their kin communities in diaspora. It draws on findings from ethnographic research focused on the Los Angeles Armenian community, including qualitative interviews not only with new emigrants from Armenia, but also with members of the old diaspora and their organisations, and on observations of immigrant activities and in diasporic spaces of encounter. Three empirical chapters demonstrate that the hegemonic diasporic discourses are not widely applicable to the newcomers, neither in relation to identity nor imaginings of the homeland. In addition, emigrant`s transnational ways of being, belonging and practices developed in ways that differ from classical diaspora assumptions. In the encounters between spiurkahays and hayastantsis, the boundaries of the diaspora, ethnicity and co-responsibility begin to be negotiated but the immigrants have continued to follow their own way of being ethnic, transnational or established in their new place of migration - located within the Armenian community spatially but outside the imagined diasporic borders.

Purpose: The study aims to explore the relationship between corporate heritage design, augmented role identities and customer behaviour towards the well-known traditional London taxi. The study scrutinises whether the city and national role identities of London black cab positively resonate among the traditional London taxi users. Furthermore, the study examines if corporate heritage design plays a moderator role in the relationship between its perceived identities and user experience. Design/methodology/approach: This study is a deductive, case study based on positivist research philosophy. Before the main research, augmented identities of the traditional London cab revealed based on initial research with the secondary data. Then, a conceptual framework developed through the relevant literature. Various hypotheses were proposed via the conceptual framework. To test the proposed hypotheses, the research adopted an online survey research method to collect the required data. Surveys were collected via social media channels such as Facebook and Twitter. At the end of the data collection process, as a sample of 523 clean survey responses were received. Results: The data were analysed by using SPSS and Structural Equation Modelling software SPSS AMOS. Within the context of traditional London taxi, data analysis validated the saliency of both city and national role identity for customer satisfaction. In addition to that, the analysis confirmed the significance of corporate heritage design on customer perceptions and responses of multiple identities (Corporate ID, City Role ID, and National Role ID) attached to the London black cab. Originality/value: This study differentiates by exploring the antecedents and impacts of corporate heritage design. On top of that, the notion city role identity and its effects are introduced to extend the understanding of corporate heritage. The conceptual framework confirms the moderation of corporate heritage design on the relationship between corporate identity, city role identity, and national role identity and customer experience. The study also identifies the antecedents of corporate heritage design (Continuity, Familiarity, Functionality, and Aesthetic). Managerial Implications: The study shows that corporate heritage design is an essential tool to communicate added identities such as national and city identity. Companies acquiring corporate heritage design should maintain those unique design elements whilst updating their products or service to satisfy customers’ modern needs. The study also suggests that companies attributed to other identities (e.g. social, territorial, cultural etc.) could increase the customer experience and satisfaction via revealing and communicating those augmented role identities. Lastly, like the traditional London cab, certain corporate heritage assets could become a symbol of a city or territory. Hence city administrators should also consider protecting those corporate heritage symbols to promote and differentiate the cities.

The field of swarm robotics studies bio-inspired cooperative control strategies for large groups of relatively simple robots. The robots are limited in their individual capabilities, however, by inducing cooperation amongst them, the limitations can be overcome. Local sensing and interactions within the robotic swarm promote scalable, robust, and flexible behaviours. This thesis focuses on synthesising and analysing minimalist control strategies for swarm robotic systems. Using a computation-free swarming framework, multiple decentralised control strategies are synthesised and analysed. The control strategies enable the robots—equipped with only discrete-valued sensors—to reactively respond to their environment. We present the simplest control solutions to date to four multi-agent problems: finding consensus, gathering on a grid, shepherding, and spatial coverage. The control solutions—obtained by employing an offline evolutionary robotics approach—are tested, either in computer simulation or by physical experiment. They are shown to be—up to a certain extent—scalable, robust against sensor noise, and flexible to the changes in their environment. The investigated gathering problem is proven to be unsolvable using the deterministic framework. The extended framework, using stochastic reactive controllers, is applied to obtain provably correct solutions. Using no run-time memory and only limited sensing make it possible to realise implementations that are arguably free of arithmetic computation. Due to the low computational demands, the control solutions may enable or inspire novel applications, for example, in nanomedicine.

The human microbiota refers to the ecosystem of microorganisms living on or within the human body, and is increasingly being implicated as a regulator of health and disease. Abnormal alterations in the development or composition of the intestinal microbiota are referred to as dysbiosis. However, the reciprocal interactions between the microbiota and the host’s diet, immunology and genetics can in turn make it extremely difficult to distinguish the cause and effect of dysbiosis in pathologies. Synthetic biology has facilitated the design and creation of more complex and clinically relevant genetic circuits. The commensal nature of the intestinal microbiota and its constituents provide a number of well tolerated microorganisms such as Escherichia coli NISSLE 1917 (EcN) that could be used as powerful investigative tools. The use of antibiotic selection within synthetic circuits would eventually hinder their investigative power during microbiota experiments. Toxin-Antitoxin (TA) post segregational killing systems are a naturally occurring bacterial mechanism to maintain plasmid stability. Here we show that the Axe/Txe TA system from Enterococcus faecium was able to significantly outperform the more widely used Hok/Sok system to maintain the stability of fluorescent and luminescent reporter plasmids in EcN without antibiotic selection during both liquid culture and in vivo animal experiments. In addition, we created a sensor circuit that in EcN could detect both exogenous and bacterial-derived reactive nitrogen species, which are thought to play a crucial role in the human host inflammatory response. We also developed biosensors for pH and the short-chain fatty acid propionate. Finally, we demonstrated that an EcN sensor could detect and report on environmental signals in vivo from the intestines of the Caenorhabditis elegans worm. Synthetic biological tools such as these could help further elucidate the underlying role of the microbiota in conditions such as inflammatory bowel disease and cancers of the gasterointestinal tract.

This thesis consists of three self-contained experimental studies focusing on conformity behavior in the leader appointment process, self-group risk preferences of elected leaders and performance feedback mechanisms. In Chapter 1, I investigate discrimination against women in election settings and whether group dynamics undermine women’s chances to become leaders. I conduct a voting experiment which tests the effect of the candidate’s gender on voting behavior, and the role of conformity. Consistent with the predictions of a simple model, subjects tend to vote for candidates who exhibit similar (risk) preferences. Information on the gender of the candidates mitigates proximity concerns of the voter especially in favor of the male candidate. Yet, there is no conclusive result for the gender bias. The results also confirm that conformity is a significant factor in group decision-making. In Chapter 2, I analyze the mechanism which induces the difference between self and group risk attitudes of elected leaders. I focus on two motivations: a “leadership effect”, that is created by the competition and the sense of responsibility of the leadership status, and a “group concern” of the leader. The results show that elected leaders significantly become more risk-seeking when deciding on behalf of a group compared to their individual decisions. Meeting the expectations of group members seems the main driver of this observed behavioral change. In Chapter 3, in a setting where feedback is given strategically by a supervisor, we theoretically and experimentally analyze how employees interpret the received feedback in forming beliefs of themselves and whether feedback communicates the iv actual performance information truthfully. We found that information transmission occurs only in verifiable feedback mechanisms and private-verifiable is the most informative mechanism. We observed lying-aversion among principles: the results indicate a lying cost, and there is a tendency to send the true information where lying is profitable.

Succession planning and successor selection is a key theme in the FOB (Family Owned Business) literature. To enable the business to continue, FOB owner needs to decide who will be the next leader before resigning. Although the succession process is one of the most researched areas within the family business field, studies have mostly focused only on incumbent or successor viewpoints. However, the purpose of this study is to fill the gap and offers a different perspective on daughters’ succession by analysing owner, successor, and employee points of view. This dissertation aims to identify cultural patterns, and how factors based on different cultural patterns influence the daughter succession process in Turkish family businesses. Additionally, aim to reach novel insights regarding women entrepreneurs in Turkish FOBs, particularly how they gain business leadership positions, and the explicit and implicit factors determining the succession process. The research is grounded in the multidimensional model of succession process in family business theory, which has been expanded to include interactive and collaborative action, by addressing the family business cultural effects associated with stewardship theory. The adoption for this study of an epistemological interpretivist philosophy within a social constructivist perspective is justified. Data was collected from in-depth, semi-structured interviews with 20 FOB owners and daughters, and surveys of 252 FOB employees to obtain information on their perspectives about selecting daughters as FOB successors.

Following Lillis and Curry (2010), in this longitudinal study, I investigated four Turkish medical specialists’ experiences of publishing their research in English. I used a multiple case study design to study the medical specialists in a non-Anglophone ‘peripheral’ context, and I employed qualitative methods.

Intergenerational relationships have provided a popular focus of enquiry for family sociology. With recent demographic shifts and structural changes in the family, intergenerational relationships have begun to shift throughout the world. Turkey, as a Muslim-majority country with strong traditional intergenerational bonds, is also undergoing demographic transition and structural changes are taking place in Turkish families. For that reason, it is significant to know how intergenerational relationships are affected by these changes. This dissertation aims to understand the nature of intergenerational relationships and how they are affected by socio-demographic factors. The Intergenerational Solidarity Approach by Bengtson and Roberts (1991) is used as the most appropriate theoretical framework for the research objectives and the Turkish context. The results of the quantitative enquiry have revealed that intergenerational solidarity is still strong among Turkish families; however, inconsistency between attitude and behaviour is detected among educated respondents, which has led to another phase of qualitative enquiry. Interviews conducted with adult and older Turkish women show that the gap between normative and felt obligations is putting pressure on educated Turkish women in particular, and that they develop different management strategies to confront the dilemmas they experience. In this respect, the Intergenerational Ambivalence Theory (Lüscher & Pillemer, 1998) is employed to address the findings of qualitative data. The results of both of quantitative and qualitative analysis show that neither the solidarity nor the ambivalence approach is fully capable of reflecting intergenerational relationships in the Turkish context. For this reason, as a final step, the dissertation suggests a theoretical model for examining intergenerational relationships in Turkish families. The suggested model embraces both the solidarity and the ambivalence models and stipulates the use of mixed methodology in intergenerational research. In this respect, this dissertation contributes to empirical, theoretical and methodological knowledge in the literature of intergenerational relationships.

Background: It is well established that there are significant disparities in health­care delivery and utilisation. These differences cannot be explained by differences in disease prevalence, evidenced based medicine or patient preference. Similarly, it is acknowledged that there is significant variation in healthcare outcomes for which our understanding is limited. This thesis details the variation in structures and processes of care between, acute NHS hospital trusts in England and studies the association of these factors with healthcare outcomes. Methods: Publicly available data sets largely provided by the Health Social Care Information Centre, were examined to describe the variation in hospital trust level structures and processes. Patient level data on a variety of diagnostic or procedural cohorts was obtained from the Hospital Episode Statistics administrative database. The cohorts studied included all hospital admissions, emergency admissions or pro­cedures, general surgical emergencies, ruptured abdominal aortic aneurysm (AAA) repair and all A A A repairs. Outcomes included mortality, complications and failure to rescue from complications. Resource provision or utilisation between risk adjusted outliers for a given outcome were compared. Multilevel hierarchical binary logistic regression models were used to identify the associations of structure and processes of care with risk adjusted outcomes. Results: There is significant variation in structures and processes of care between hospital trusts. Trusts with the most favourable outcomes had significantly greater levels of staffing, critical care and radiodiagnostic utilisation. Greater medical and nurse staffing levels, radiodiagnostic utilisation, research activity and procedural volume were associated with better healthcare outcomes for a variety of cohorts. Conclusions: This thesis demonstrates that hospital trust level variation in struc­tures and processes of care is associated with the outcome for a broad range of patients. Further research should examine the underlying mechanisms for these associations and, the clinical and cost-effectiveness of resource modification at the trust level.

Current work is a thorough investigation on the processing and mechanical properties and the toughening mechanism of nanorubber-modified epoxy and the carbon and glass fibre reinforced composites produced using these matrices. The study is aiming to assess the applicability of these novel nanorubber-modified matrices to advanced industrial applications where fracture toughness is the main concern. In the first section of this research, process optimisation of the nanorubber-modified epoxy was studied. Dispersion techniques of triple milling, high shear mixing and ultrasonic bath were used in order to enable an even and nano-size dispersion of the acrylonitrile-based nanorubbers in the epoxy matrix. Triple milling was chosen as the dispersion technique which enabled an even and nano-scale dispersion of the nanorubber particles in the epoxy resin matrices. Scanning electron microscopy (SEM) images revealed that CNBR-NP could be dispersed evenly in the epoxy matrix using industrial mixing process whereas partial agglomeration was observed in NBR-NP blends. The difference in the dispersion ability of these two nanorubbers in epoxy was related to the difference in van der Waals forces between single nanoparticles, the chemical formula and the polarity of the systems. In the second stage of this study, the effects of nanorubber on the rheological properties, cure characteristics and mechanical properties of epoxy resin were investigated. The dynamic mechanical behaviour of the carbon fibre reinforced polymer composites (CFRP) with the neat and the nanorubber-modified matrices was also studied. Rheological study showed that the NBR-NP blends attained lower viscosity in comparison to CNBR-NP blends and both systems exhibited shear-thinning behaviour. The dynamic mechanical analysis (DMA) data showed that the addition of nanorubber has negligible effect on the glass transition temperature of the epoxy. The effects of the nanorubber on the interlaminar shear strength, fracture toughness and tensile fatigue behaviour of carbon and glass fibre reinforced polymer composites (CFRP, GFRP) was studied. Mechanical properties of tensile strength, apparent shear strength, Mode I and Mode II delamination fracture toughness, impact toughness and tension-tension fatigue were analysed. The results showed that the nano-size dispersion of rubber significantly improved the Mode I delamination fracture toughness (G[sub]IC) of the CFRP by 251% and its Mode II delamination fracture toughness (G[sub]IIC) by 81% with the addition of 20 phr of CNBR¬NP to the resin matrix. For the NBR-NP system, the G[sub]IC and G[sub]IIC delamination fracture toughness of the CFRP were improved by 203% and 83% respectively with the addition of 20 phr of NBR-NP to the matrix;. Scanning electron microscopy (SEM) images of the CFRP fracture surfaces revealed that the toughening was mainly achieved by the de-bonding of nanorubber, crack path deflection and fibre bridging. The Mode I delamination fracture toughnesses (G[sub]IC) of the GFRP with the addition of 20 phr of CNBR-NP and NBR-NP were improved by 190% and by 150% respectively. Similarly, the Mode II delamination fracture toughness (G[sub]IIC) of the GFRP panels was improved by 73% and 67% with the addition of 20 phr of CNBR-NP and NBR-NP respectively. SEM images of the Mode I delamination fracture surface of the GFRP panels proved that the interfacial adhesion between the individual glass bundles and the matrix was improved with the addition of nanorubber. The tensile-fatigue behaviour of the CFRP panels with X CNBR-NP/ R matrices was studied. The normalised test data revealed that the high cycle fatigue life was enhanced by twice with the addition of 15 phr of CNBR-NP in the neat epoxy matrix. SEM images of the fracture surfaces proved that the better. adhesion of nanorubber-modified matrix to the carbon fibres supressed fibre pull-out and contributed towards the enhanced fatigue life of the panels.

In a city where more than half the population lives in squatter housing, the transformation of squatter housing into apartment blocks has important consequences on the socio-spatial structure of the city. This thesis aims to provide an account of the recent transformation of squatter settlements in Ankara into apartment blocks, with special reference to the political, economic, cultural as well as spatial consequences of this transformation. The theoretical part of the thesis has shown that existing theories on the formation and transformation of squatter settlements fail to provide an adequate account of their formation. While the articulation approach seems to be the most adequate for illustrating the formation of squatter settlements, it too remains silent in the face of transformation processes of squatter housing into apartment blocks on such a massive scale. In order to explain this process, rent gap theory. which was developed for the study of gentrification, is applied to the case of squatter transformation. Along with these structural dynamics, the political and ideological motives behind this policy shift on squatter settlements are also emphasised. In order to provide a holistic view of the development of squatter housing in Turkey, and particularly in Ankara, a brief review of the trajectory of squatter development in Turkey and in Ankara is provided with reference to state policies in this area. It is revealed that state strategies towards the squatter have undergone dramatic changes, from complete denial to covert acceptance, and then to overt support partly due to the increasing negotiation power of the squatter dwellers. In this context, the recent transformation of the squatter settlements needs to be understood with reference to this negotiation process as well as to the strategic location of the land occupied by the squatter settlements for redevelopment. Regarding the repercussions of this massive scale transformation on the city as a whole, and the different groups involved in this process, the case studies has shown that despite the considerable difference between the public and private sector-led transformation schemes, the main losers were the tenants, as they were forced to leave the areas that were subjected to redevelopment. Ironically, although the squatter owners received flats and in some cases cash for their land plot at the end of redevelopment process, this return is far from meeting their initial expectations. The main winner seems to be developers, public or private, in the redevelopment process. Yet, in the long term, the main loser seems to be the city population on the whole, as the newly emerging environments, as a result of redevelopment, reduced the environmental standards of the city and created a city that was intended to be avoided by the original development plan.

This work presents an investigation of the effect of cold-expansion methods on both residual stress distributions and fatigue life improvements in a high strength 7050 T76 aluminium alloy. Cold-expansion is usually achieved by the FTI split-sleeve process using commercially available equipment and prescribed levels of mandrel interference. A cold-expansion system has also been developed at the Open University which allows the degree of cold-expansion to be infinitely varied in a simple manner. The nature of residual stress distributions after the FTI split-sleeve and the Open University processes are evaluated by a mechanical (destructive) method based on Sachs boring-out technique. Since the Sachs method requires cylindrical specimens, 40mm diameter washers concentric with expanded holes have been produced from original rectangular specimens. To allow for any stress relaxation caused by washer manufacture, relevant compensation equations have been developed and are used to compensate the evaluated residual stresses after each Sachs experiment. It is revealed that residual hoop stresses produced by the FTI split-sleeve method are more compressive than that are produced by the Open University method. Residual hoop stress distributions are found to be unaxisymmetric and orientation dependent. In the FTI split-sleeve process, the presence of the split increases the magnitude of the compressive hoop stress adjacent to the hole. In addition, the residual hoop stresses in the transverse direction are more compressive than the residual hoop stresses in the rolling direction of rectangular specimens. This has been attributed to the geometry of the specimen as differences in material constraints in the transverse and rolling directions which influence the extents of plastic deformations and the resultant residual stress distributions. Residual stresses are also found to be nonuniform in the thickness direction. At FTI split sleeve expanded holes, the mandrel entrance side (inlet) has a lower residual compressive hoop stress.

Conventional farming on Ultisols that are dominant in Southeast US has resulted in the loss of soil organic matter over time. Conservation tillage farming practices that incorporate different cover crops are shown to increase soil organic matter. Soil organic matter is the lifeblood and basis of soil health. Soil microorganisms play a critical role in the breakdown and mineralization of cover crops that are incorporated into soil. Different types of soil microbes are involved in mineralizing different cover crops. Relationships between soil microbes’ diversity and activities in soil are dependent on soluble organic sources. Although the impact of cover crops on soil physical, biological, and chemical properties in general are well established, there are still many gaps in our knowledge on the effects of specific cover crops on soil microbial diversity and populations and, soil physical-chemical properties under specific environmental conditions. Hence, the objectives of our studies were to evaluate three cover crop species, cereal rye (Secale cereale), crimson clover (Trifolium incarnatum), and forage radish (Raphanus sativus L.) and their mixtures in a soybean (Glycine max L.)–corn (Zea mays.) rotation under strip tillage on selected soil properties; investigate the impact of the cover crops on nematode population and phonology, microbial activities, and soil properties at different soil depths. The field experiment was a randomized complete block design with four replications. Treatments were fallow (no cover crop), clover, rye/clover, rye/radish, clover/radish, and rye/clover/radish (3-way mixtures) mixtures. Cover crops had significant impacts on soil respiration, active carbon, labile amino nitrogen, C:N ratio, compaction, bulk density, predator, and bacterial feeding nematodes by soil depths. Cover crops did not significantly affect total organic carbon and nitrogen, organic matter, plant parasitic nematode, fungal feeding nematode, and omnivore in all depths by year. Nematode populations for all feeding groups were considerably high at 0-10 cm depth compared to lower soil depths. This study will contribute to our understanding of the impact of cover crops on Ultisols of Alabama.

Metal-organic frameworks (MOFs) are crystalline, porous materials comprised of symmetric organic linkers coordinated to positively charged metal atoms or metal oxide nodes. This dissertation uses strategies in crystal engineering to advance the study of functional MOFs with emphasis on thin film deposition. The first chapter of this dissertation will introduce the field of reticular chemistry to the reader and describe synthetic efforts to develop useful building blocks for MOF materials: namely porphyrin macrocycles and carboxylate capped zirconium-oxo and hafnium-oxo clusters. The building blocks for MOFs developed in the first chapter will be employed in the second and third chapters through incorporation into MOF thin films through molecular deposition and bulk deposition respectively. New methods for the molecular deposition of Hf-based MOF films are described which will expand the available MOF types which are known to be deposited in a molecular layer-by-layer fashion. A key methodology is the use of Hf-oxo clusters capped by carboxylate ligands to be used as a potential Hf source for molecular layer-by-layer Hf-MOF deposition. Using an automated epitaxial workstation, films of UiO-66 (Hf) are fabricated for the first time and porphyrinic Hf-based MOFs are developed for catalytic applications. Following these efforts, experiments regarding the bulk-deposition of UiO-66 and UiO-66 (Hf) films are laid out. The UiO-66 (Hf) bulk deposited films are shown to be a promising catalyst for CO2 fixation to epoxides for cyclic carbonate synthesis.

Polymer membranes are used extensively in large lightweight structures applications such as superpressure balloons. Design of these structures for long-term operations requires accurate modeling and characterization of the permanent deformation appearing in the structures due to the time and temperature-dependent properties of polymers. This work presents analytical, numerical, and experimental investigations of the onset of residual strains of a viscoelastic polymer membrane subjected to creep loading at various temperatures. The aim of this study is to establish a model that can be employed to determine the time-to-yield given the stress and temperature history a polymer membrane experiences. Two possible time-dependent criteria, the free energy criterion and the kinematic criterion are formulated for the material and their performances are investigated with the experimental data. The experimental data consist of uniaxial and biaxial material behavior characterization and residual deformation experiments are carried out at various temperatures. Biaxial experiments are conducted with the novel inflated cone experimental setup. The inflated cone method leverages the specimen geometry to achieve a non-uniform stress field when differential pressure is applied. The resulting non-uniform strain field is captured with full-field displacement measurement methods, i.e., digital image correlation. This method accelerates the experimental data collection process. The free volume nonlinear viscoelastic model for the material is calibrated with the experimental data obtained at various temperatures and stress levels. The developed kinematic model in conjunction with the nonlinear viscoelastic model can be used to estimate the residual strains if the stress and temperature history a polymer membrane experiences are given. Similarly, the criterion can be used in an inverse design problem to limit the creep stresses and corresponding allowable durations.

Structural pounding occurs when two or more structures with insufficient separation distances in between collide under earthquake loading. It occurs as a result of out-of-phase responses of structures due to differences in their dynamic properties. Seismic pounding damage has been observed in several earthquakes such as Mexico City earthquake in 1985 (Rosenblueth and Meli, 1986), Loma Prieta in 1989 (Kasai and Maison, 1997), and more recently Gorkha earthquake in 2015 (Shrestha and Hao, 2018). The extent of seismic pounding damage ranges from minor crushing to catastrophic collapse of the colliding structure, even though recent design codes provide guidance on mandatory separation gaps to prevent pounding; still, in dense metropolitan areas with growing populations and constructors willing to make the maximum use of available lands, structural pounding is becoming a significant matter that needs attention in the design of new buildings. Over the past decades, simulating structural pounding and assessing the resultant pounding forces have attracted the attention of many researchers. Simulating pounding between two structures and the extent of pounding damage started from a simple model that could only estimate the elasticity and plasticity of a damage using the pre- and post-impact velocities. The research gradually evolved to analytical force-based models called contact element models (other names are impact element or gap friction element models) that simulate pounding between structures idealised as lumped masses. These models have been widely used and modified numerous times; however, they suffer from a lot of uncertainties associated with their contact parameters (i.e contact stiffness, coefficient of restitution, and damping ratio) as proper methods/formulas to calculate the parameters for contact between flat surfaces do not exist. Progressively, these force-based models were implemented in commercial software as gap elements to model structural pounding. In this method of modelling, the gap elements were placed between the colliding structures to measure contact forces. Within the gap element approach, contact parameters have to be defined in advance and be inputted into the gap element before the start of the simulation, and yet the uncertainties with selecting suitable contact parameters persist. The selection of contact parameters influences the pounding response of the structures significantly. Therefore, diverse results are obtained from the existing methods of modelling pounding (Khatiwada and Chouw, 2014). This research work intends to develop a methodology that properly simulates building pounding using the Finite Element Method (FEM). In this methodology, pounding between buildings is modelled using a penalty-based method. Using the proposed FE method, there is no need to define/ or assume contact parameters in advance and the reliability of the simulation is based on the material models used in the simulation. Unlike the existing lumped mass contact models with pre-defined contact points and limited locations to extract data, in the FE model the contact surface area, time of contact and the duration of contact can be obtained anywhere on the colliding buildings. Satisfactory data such as force, displacement, velocity, and acceleration-time histories at every microsecond of the seismic motion is easily accessible. To develop this methodology that leads to a more accurate FE model, contact phenomena at material level (i.e concrete and steel) has been studied using direct impact Hopkinson Pressure Bar (HPB) experiments. Direct HPB numerical simulations were validated against the experiments in LS-DYNA. The results of the investigation at the material level were taken onto the structural level and were combined with numerical simulations of shaking table tests validated against shaking table experiments conducted by Garcia et al. (2010). At a later stage, the findings of the experiments and the numerical simulations are combined into a final FE model that can simulate pounding with more accuracy compared to the existing methods of pounding simulation demonstrating the magnitude of the contact forces and the extent of damage in the colliding concrete buildings. The developed approach allows better insights into the structural and material response mechanisms during earthquake events. Also, more reliable contact parameters can be extracted from the developed FE model and be implemented onto the existing pounding models.

This thesis presents analytical, experimental and modeling studies of the shape recovery behavior of electrically activated Carbon Nanopaper (CNP) Shape Memory Polymer (SMP)composite. The composite structure studied consists of a CNP layer sandwiched by two SMP layers where the CNP layer acts as a flexible electrical heater when a voltage difference is applied. The behavior of CNP/SMP composite presents a coupled electrical - thermal - structural problem. The governing equations for the multiphysics behavior are derived. Derived parameters as a result of multiphysics analysis and effects of these parameters on the shape recovery behavior are investigated. The mechanical properties of the carbon nanopaper and viscoelastic properties of the shape memory polymer are characterized. A nonlinear, fully coupled electrical -thermal-structural finite element model is developed, and shape recovery experiments are carried out to validate multiphysics analysis and finite element model of the shape recovery of the CNP/SMP composite. Finite element model captures the general behavior of shape recovery, but overpredicts shape fixity and shape recovery rate.

Robust parameter design (RPD), originally conceptualized by Taguchi, is an effective statistical design method for continuous quality improvement by incorporating product quality into the design of processes. The primary goal of RPD is to identify optimal input variable level settings with minimum process bias and variation. Because of its practicality in reducing inherent uncertainties associated with system performance across key product and process dimensions, the widespread application of RPD techniques to many engineering and science fields has resulted in significant improvements in product quality and process enhancement. There is little disagreement among researchers about Taguchi's basic philosophy. In response to apparent mathematical flaws surrounding his original version of RPD, researchers have closely examined alternative approaches by incorporating well-established statistical methods, particularly the response surface methodology (RSM), while accepting the main philosophy of his RPD concepts. This particular RSM-based RPD method predominantly employs the central composite design technique with the assumption that input variables are quantitative on a continuous scale. There is a large number of practical situations in which a combination of input variables is of real-valued quantitative variables on a continuous scale and qualitative variables such as integer- and binary-valued variables. Despite the practicality of such cases in real-world engineering problems, there has been little research attempt, if any, perhaps due to mathematical hurdles in terms of inconsistencies between a design space in the experimental phase and a solution space in the optimization phase. For instance, the design space associated with the central composite design, which is perhaps known as the most effective response surface design for a second-order prediction model, is typically a bounded convex feasible set involving real numbers due to its inherent real-valued axial design points; however, its solution space may consist of integer and real values. Along the lines, this dissertation proposes RPD optimization models under three different scenarios. Given integer-valued constraints, this dissertation discusses why the Box-Behnken design is preferred over the central composite design and other three-level designs, while maintaining constant or nearly constant prediction variance, called the design rotatability, associated with a second-order model. Box-Behnken design embedded mixed integer nonlinear programming models are then proposed. As a solution method, the Karush-Kuhn-Tucker conditions are developed and the sequential quadratic integer programming technique is also used. Further, given binary-valued constraints, this dissertation investigates why neither the central composite design nor the Box-Behnken design is effective. To remedy this potential problem, several 0-1 mixed integer nonlinear programming models are proposed by laying out the foundation of a three-level factorial design with pseudo center points. For these particular models, we use standard optimization methods such as the branch-and-bound technique, the outer approximation method, and the hybrid nonlinear based branch-and-cut algorithm. Finally, there exist some special situations during the experimental phase where the situation may call for reducing the number of experimental runs or using a reduced regression model in fitting the data. Furthermore, there are special situations where the experimental design space is constrained, and therefore optimal design points should be generated. In these particular situations, traditional experimental designs may not be appropriate. D-optimal experimental designs are investigated and incorporated into nonlinear programming models, as the design region is typically irregular which may end up being a convex problem. It is believed that the research work contained in this dissertation is the initial examination in the related literature and makes a considerable contribution to an existing body of knowledge by filling research gaps.

We demonstrate that explicit and systematic incorporation of abductive reasoning capabilities into algorithms for blind signal separation can yield significant performance improvements. Our formulated mechanisms apply to the output data of signal processing modules in order to conjecture the structure of time-frequency interactions between the signal components that are to be separated. The conjectured interactions are used to drive subsequent signal separation processes that are as a result less blind to the interacting signal components and, therefore, more effective. We refer to this type of process as early abductive reasoning (EAR); the “early” refers to the fact that in contrast to classical Artificial Intelligence paradigms, the reasoning process here is utilized before the signal processing transformations are completed. We have used our EAR approach to formulate a practical algorithm that is more effective in realistically noisy conditions than reference algorithms that are representative of the current state of the art in two-speaker pitch tracking. Our algorithm uses the Blackboard architecture from Artificial Intelligence to control EAR and advanced signal processing modules. The algorithm has been implemented in MATLAB and successfully tested on a database of 570 mixture signals representing simultaneous speakers in a variety of real-world, noisy environments. With 0 dB Target-to-Masking Ratio (TMR) and no noise, the Gross Error Rate (GER) for our algorithm is 5% in comparison to the best GER performance of 11% among the reference algorithms. In diffuse noisy environments (such as street or restaurant environments), we find that our algorithm on the average outperforms the best reference algorithm by 9.4%. With directional noise, our algorithm also outperforms the best reference algorithm by 29%. The extracted pitch tracks from our algorithm were also used to carry out comb filtering for separating the harmonics of the two speakers from each other and from the other sound sources in the environment. The separated signals were evaluated subjectively by a set of 20 listeners to be of reasonable quality.

Rapid urbanisation and population growth in developing countries have increased seismic risk regardless of the advances in our knowledge on the seismic behaviour of structures. The need to cover the demand for a low-cost building stock has led a large proportion of residential buildings to be constructed with substandard materials, insufficient designs and poor construction practices. These are the reasons that developing countries have exhibited considerably higher death rates compared to the developed world. Extensive losses and mortality rates observed during recent major earthquakes in developing countries highlight the high seismic vulnerability of existing substandard RC buildings. This research aims to develop a vulnerability framework (for substandard RC buildings) which can produce advanced adaptive vulnerability curves. For this, an analytical modelling procedure was proposed and validated against field and large-scale tests data. OpenSees is employed for modelling full-scale substandard RC columns and shake-table RC frames and the analytical model is verified against the experimental results, at both local and global level. An advanced probabilistic seismic vulnerability framework is developed using Matlab code linked with OpenSees. General vulnerability curves are derived (using an improved CSM) for substandard RC columns as well as an existing 4-storey substandard RC building (case study for Marmara region). The general fragility curves are then disaggregated to derive adaptive fragility curves based on various considered parameters e.g. steel grade, concrete strength, transverse rebar spacing, axial load level. Upgraded fragility curves are obtained by considering external retrofitting with FRP sheets on the case study building. Finally, vulnerability curves are derived for the RC columns and the case study building, using an existing conversion matrix for the case study region. The developed framework showed that the use of advanced adaptive vulnerability curves can improve the accuracy by up to 20% compared to general vulnerability curves. The study on the upgraded vulnerability analysis using 3 layers of CFRP (for the case study building), revealed that seismic vulnerability can be reduced up to 85% and 45% for slight and collapse damage limit states, respectively.

The devastation of the past earthquake events such as Kocaeli (1999), Kashmir (2005) and Haiti (2010) highlights the need for an earthquake risk assessment (ERA) framework, which can be applied to developing countries to reduce future earthquake losses. Although there are several ERA frameworks used in current practice, these frameworks are not flexible or applicable to the areas with limited input data and lacking assessment of earthquake induced secondary hazards. One of them is liquefaction, which is capable of causing settlement, tilting or even collapse of the structures. As an example, numerous liquefaction manifestations in Adapazari during 1999 Kocaeli and 1999 Chi-Chi earthquakes caused damage to a significant number of buildings due to ground failures. This past experience highlighted the importance of the integration of liquefaction hazard assessment into the existing or future earthquake risk assessment frameworks. This research presents the development of the multi-hazard ERA framework, which can be applied to the areas with limited input data available. The proposed framework is based on Monte-Carlo simulations and consists of three main modules: Probabilistic Seismic Hazard Analysis (PSHA), Probabilistic Liquefaction Hazard Analyses (PLHA) and Seismic Risk Assessment. The developed PSHA module generates earthquake catalogues using Monte-Carlo simulations to represent future seismicity of the region of interest. In this module, both Poisson and time dependent (renewal) models are adopted to quantify the effect of temporal dependencies between seismic events, while near-field rupture directivity effects are also taken into account. The Marmara region in Turkey is selected as a case study region. The PSHA results compare well with the recent studies performed for the study region. The PLHA module of the framework uses Monte-Carlo simulations and simplified liquefaction assessment procedures to predict earthquake induced liquefaction hazard in a probabilistic way. The module provides a relatively flexible approach to treat uncertainties of the earthquake and soil related input parameters by including such parameters with distribution functions. Liquefaction Potential Index (LPI) and Liquefaction Severity (LS) procedures are adopted for the prediction of liquefaction hazard. The PLHA module is applied to the city of Adapazari in Turkey, which is located in a liquefaction prone area. A set of probabilistic liquefaction hazard maps are derived for Adapazari as there were no PLHA studies performed for the city. The PLHA module is verified with a scenario earthquake and observed liquefaction from the 1999 Kocaeli earthquake. Seismic risk assessment module uses readily available data such as building stock and population data from census, global shear-wave velocity maps and satellite images. Seismic risk assessment module is applied to Adapazari. An exposure model for buildings in the case study area is developed by mapping buildings footprints from aerial and satellite images and using remote street survey. The risk results are presented in terms of loss curves and probabilistic mean damage ratio (MDR) maps considering various return periods and vulnerability models. Casualty models are incorporated into the framework for estimation of fatalities associated with earthquakes in the city of Adapazari. Social and economic losses are verified with a scenario earthquake similar to 1999 Kocaeli earthquake. The developed ERA framework can serve as an efficient tool for the assessment of liquefaction hazard and seismic risk in the areas with limited data available. Although, due to lack of reliable procedures for accounting damage due to liquefaction in large scale seismic risk studies, the risk module of the framework should be used with caution in the areas prone to liquefaction. The proposed framework and its outcomes can be used by policy and stakeholders for earthquake preparedness and developing emergency response and recovery strategies.

Reduced Beam Section (RBS) connections are widely adopted within seismic design codes for steel moment resistant frames. Accurate cyclic representations for RBS connections are important for the design and retrofitting of connections. Research has shown that the geometry of RBS connections affects its non-linear cyclic hysteresis. Currently, there is no method available which can accurately represent non-linear strength and stiffness degradation for any size RBS without the need for full finite element or experimental tests for calibration purposes. In this research, a more efficient design methodology for RBS connections is proposed by investigating the geometries which define the RBS connection. Then a detailed and comprehensive database of highly accurate cyclic hysteretic models of 1480 different RBS connections is presented. This database should prove useful in better understanding the seismic performance of RBS connections. Using this database, calibrated models which could accurately predict the non-linear cyclic behaviour including stiffness and strength degradations were developed. Using this calibrated data set, highly accurate and reliable neural networks were trained and developed that are capable of predicting the full cyclic hysteresis of any RBS connection; given the geometries which define the connection as an input. A mode accuracy of 98% for these networks was achieved. Following on from this work, a proof of concept for the application of this work for the design and assessment of steel moment resistant frames was investigated, by utilizing the deep learning neural networks to predict the local RBS connection hysteretic models. Finally, the potential for additive printing (3D printing) in the design of future connections has been suggested through a critical literature review. The results from this research clearly show that the three geometrical parameters which define the RBS connection influence the seismic design parameters of the connection. Design equations to predict the effects the key seismic design parameters have on RBS connections compared with a corresponding full steel connections has been proposed. Interestingly, the sections could be categorised into two sets depending on their buckling characteristics after being subjected up to a performance-based design loading criteria corresponding to collapse prevention. This database was used to calibrate improved models capable of representing RBS non-linear hysteresis. Comparisons between these calibrated parameters and the values predicted from equations available in literature gave significant differences. The differences were a result of 1) the regressional equations available in literature were based on a limited number of data points 2) a number of different types, sizes and shapes of RBS configuration were in the database and 3) the cut which defines the RBS geometry was not taken into account. Consequently, a set of deep learning neural networks enabled the non-linear cyclic hysteresis incorporating strength and stiffness degradation to be predicted for any section given the section properties and RBS geometry of the connection as an input. A proof of concept shows how the models developed in Chapter 4 would prove useful in the design and assessment of steel moment resistant frames. To conclude this research, the realistic implementation of how this work can be applied to the potential use of additive printing through a critical literature review has been presented. Finally, future work and recommendations have been suggested.

The success of wind power as a renewable energy source depends on its cost of energy. Wind turbine control has attracted much attention in the controls community due to its potential impact on the cost of wind power. However, novel methods in the literature have not transitioned well to industry. This is because the potential cost benefits of these methods are not well understood. There is a need for basic research to address this issue. This thesis is one step toward transitioning of advanced control methods in literature to the industry. Particularly, we aim to understand the limits of performance. The potential performance improvements of the advanced methods should be large enough to justify their cost and complexity. We investigate the optimal trade-offs between multiple turbine performance goals. We also explore the use of a novel wind preview sensor in closed-loop control laws. The impact of this novel sensor on the optimal turbine performance is investigated. The specific contributions of this thesis can be grouped in three categories. First, we present a preliminary, nonlinear optimization based controller design and analysis framework. This framework can simplify the design of the advanced multivariable controllers for nonlinear systems. It can also be used to investigate the optimal design trade-offs between nonlinear performance constraints and objectives. Second, engineering insight is provided into turbine design trade-offs. Third, we provide mathematical tools that quantify the limits of turbine performance in presence of preview wind measurements. Optimization tools that can analyze the trade-off between preview time and operating condition dependent turbine performance objectives are presented. In low wind speeds, our results show that simultaneous power capture improvements and structural load reductions can be obtained. In high wind speeds, a short amount of preview wind information can be used to overcome the fundamental performance limitations imposed by actuator rate constraints. We provide analytical formulas that quantify these preview time requirements and performance limitations. A convex optimization framework is also presented for the analysis of extreme operating conditions that are defined by deterministic wind disturbance trajectories.

The structural and the rheological properties of corn stover biomass are analyzed applying material testing techniques. Developing testing methods to determine the hardness, reduced elastic modulus, and multiple axis fiber strength is one of the challenges of this study. Hardness and reduced elastic modulus parameters of corn stalk fibers are determined through a nanoindentation machine, NANOVEA®. Tensile strength and flexure tests are performed using a universal testing machine, MTS Insight®. Rheological properties (internal friction coefficient, angle of internal friction, and cohesion) of chopped corn stover biomass in bulk are analyzed using a custom direct shear cell and compared to the limited findings in literature. The measured properties of the biomass have the potential to be used in computer simulations for bulk solid flow analysis. The bulk fluid motion of the pulverized/chopped biomass can be simulated in storage and transportation equipment, including auguring screws and pneumatic conveyance systems, as well as devices for feeding biomass feedstocks in biorefineries. Traditional biochemical and thermochemical reactors operate as batch systems because of the difficulty of feeding the biomass feedstock in a continuous manner. Having a clearer background about the structural and rheological properties of biomass feedstock will help simulate and design the bulk-solid flows within storage bins and conveyance systems.

Bio-composite fibers have attracted increasing attention from environmentally-conscious consumers because of their low cost and biodegradability. Soy protein isolates and other purified forms have been proposed as bio-based substitutes for pure synthetic polymers for use in textiles. However, fibers from pure soy proteins do not possess adequate properties for use as textile fibers. Therefore, this research aimed to investigate composite fibers consisting of soy and polyethylene for their microstructure and mechanical properties. Changes in properties with increasing filler content and long-term properties of fibers were systematically examined. First, the microstructure of the fibers was investigated by optical analysis. Six different compositions of soy, compatibilizer, and polyethylene were examined: 0-0-100, 0-10-90, 20-0-80, 23-7-70, 20-20-60, and 30-20-50. The pure PE and C-PE fibers had very smooth surfaces, which became rough after soy particles were added. Without a compatibilizer, soy-PE fibers had the lumpiest surface with large soy agglomerates. The soy particles on fibers made from 23-7-70 composition had a more homogenous distribution, and better dispersion (less agglomerates) than that on other fibers. Overall, the soy agglomerates oriented along the fiber direction due to shear and extensional stresses induced during flow and draw-down. Second, the mechanical properties of fibers were analyzed. For fibers produced from 23-7-70 composition, tensile modulus reduced from 921 ±85 MPa to 570±94 MPa, and ultimate strength reduced from 500±90% to 67±63 % with the addition of soy to PE. Adding soy flour to polyethylene resulted in a decrease in tensile modulus and ultimate strain. Yield stress and tensile strength did not differ significantly between the fibers having 100% PE and 50% PE. However, tensile strength of 23-7-70 fibers increased to 84.2±10.6 MPa compared with that of pure PE measured at 42±6 MPa. Moreover, tensile strength of 23-7-70 fibers decreased after two month of aging. However, at ambient conditions, another four months of aging had no further effect. Overall, it changed from 84.2±10.6 MPa (non-aged) to 24.2 ±1.1 MPa after six months of aging at ambient conditions, whereas other mechanical and physical properties were not affected significantly. Exposure to boiling 0.1 M NaOH aqueous solution for 10 min (to simulate accelerated washing) caused a decrease in tensile strength, but additional exposure of 90 min did not cause any further reduction in tensile strength (25±4 MPa). The fiber surface became smoother due to the removal of soy particles from the surface after boiling. Thus, over-washed fibers had a lower strength at break, but the fibers retained a moderate strength. These results indicate that soy-PE fibers possess moderate mechanical, physical and long-term properties for likely use in textile applications. The primary advantage of such fiber is their lower cost relative to that of pure PE fibers.

From Goethe to Maupassant, the act of seduction has fascinated writers. Consequently, seduction —as stimulation of love and pleasure- has been discussed often; however, its psychological motivations (other than pleasure), and its consequences have not been sufficiently studied, particularly with regard to the works of the French author Guy de Maupassant. When analyzing the notion of seduction in Maupassant’s works, many critics, such as Mary Donaldson-Evans or Nicholas White, evoke its sexual nature and its narrative manifestations, but no one has specifically written about the driving force behind the act of seduction. Nor has anyone remarked upon the paradoxical nature of his representation of seducer and seducee- their roles are often blurred. I thus propose to remedy this critical oversight by exploring aspects of the psychology and motivations of seduction as well as its effects in the three novels by Maupassant, Bel-Ami. Une Vie ar,d Pierre et Jean. My research will show that Maupassant’s characters use seduction either to satisfy a latent desire, resolve an unconscious issue, or to escape from the environment to which they belong. This study will adopt diverse methodological approaches applied to the function of seduction. Historical analysis of the nineteenth-century period, psychological research, and philosophy will be the major resources for this study. Indeed, Jean Paul Aron’s analysis of the conditions of nineteenth-century women will supply a better understanding of the motivations behind seduction during that time period. Likewise, the psychological research on “seduction behaviors” by Lyse Lebeau and Duart Maclean, among others, will help me to better explain the attitudes of seducers in the novels. Furthermore, Vincent Descombes’ idea that “there is seduction every time truth is hidden” will be an important element of the study. In the layout of my study, I will separate conscious and subconscious motivations of the seducers. For that purpose, in the first part of the thesis, with an historical perspective, I will first explain how male characters in Bel-Ami and Une Vie consciously seduce women in order to modify their social status and to improve their standard of living. We will then determine if the women voluntarily allowed themselves to be seduced in order to take advantage of the personal and social fulfillment not permissible to women in nineteenth century society. Referring to women’s condition in the nineteenth century, we will study the manipulation techniques that female characters of Bel-Ami use in order to enter the man’s world, to become sexually and socially free, and finally to simulate a high-society relationship that was not permissible at that time. Second, with the help of historical studies about women’s conditions and girls’ education in the nineteenth century, we will analyze the semi-subconscious motivations of the female characters in Bel-Ami, Une Vie, and Pierre et Jean that push the women to seduce in order to live an imaginary life and experience a story-book love. This will lead us to the second part of the thesis in which we will analyze the subconscious reasons behind the act of seduction. First, adopting a psychological perspective, I will demonstrate that the male characters use seduction to appeal to women in order to be accepted by them. In other words, I will prove that it is their lack of selfconfidence, and the weakness of their ego that compels them to seduce. Second, from a Freudian perspective, I will show how seduction is related to the Oedipus complex. Ultimately, in this thesis, I will attempt to demystify the notion of seduction in Maupassant’s novels.

Alternative round tube profiles to straight microchannel (SMC) tube geometry was explored by gradually applying the microchannel features to fin and tube type heat exchangers. First, previous experimental and computational works related to design and heat transfer analysis of microchannel heat exchanger tubes and testing was reviewed and then a numerical CFD model in FLUENT solver was developed, which was experimentally validated within an error range of 0.1 to 7.8 % based on available data in literature. Single phase, water to water, laminar, counter fluid flow of tube in shell calorimeter heat transfer experiments were numerically simulated to analyze the refrigerant side heat transfer enhancement if round microchannel tubes are used as outdoor coil. According to numerical results, the refrigerant side heat transfer capacity of round tubes of 10.3mm outer diameter with 42 microports of about 0.6 mm port diameter distributed around the tube perimeter (round tube microchannel) was estimated to be about 24% higher than conventional round tube (with no microchannel ports in them) and about 15% lower than conventional straight microchannel tube heat exchangers used in outdoor evaporators. In addition to refrigerant side, parametric studies were performed to investigate the heat transfer effectiveness of 10.3 mm and 5.15 mm outer diameter round (microchannel) tubes (multi port and annular) under cross flow configuration with dry air streams and results were compared with straight microchannel tubes in terms of tube diameter tube spacing effect. It was obtained that the round tube design of 5.15 mm outer diameter having an annular port of 1.6mm hydraulic diameter within 11mm edge to edge tube spacing of vertically parallel fin and tube coil configuration can provide similar air side heat transfer capacity of straight microchannel coil based on its secondary heat transfer area. Additionally, this configuration can provide 50 % better pressure drop performance compared to conventional straight microchannel tube coil.

The purpose of this study was to investigate the effects of context-dependency of seductive details on recall and transfer in multimedia learning environments. Two experiments were conducted. In Experiment 1, the purpose was to identify context-dependent vs. context-independent seductive details in a lightning animation. Seductive details were considered as interesting yet irrelevant sentences in the narration of lightning animation. Sixty-seven undergraduate students participated in Experiment 1 and assigned interestingness scores to the 28 content irrelevant sentences. Participants were assigned to two different groups, context-dependent seductive details group (CDSD) and context-independent seductive details group (CISD). Participants in the CDSD group assigned interestingness scores after watching a lightning animation to be familiarized with the context of lightning formation. Participants in the CISD group watched a historical inquiry animation as a distraction task before assigning interestingness scores. The results of Experiment 1 revealed that 13 of 28 sentences in the lightning formation text were seductive details according to participants of the study. Ultimately, 6 of the 13 seductive details were determined to be context-dependent and 7 were determined to be seductive details were context-independent. The purpose of Experiment 2 was to investigate the effects of context-dependency of seductive details on recall and transfer in multimedia learning environments. Undergraduate students (n = 184) were randomly assigned into four groups. Participants in all groups watched a lightning animation, and performed a recall and a transfer task. The first group watched an animation that did not include any seductive details. The second group watched the animation with context-dependent seductive details only. The third group watched the animation with context-independent seductive details only. The last group watched the animation with both types of seductive details. A 2x2 ANOVA for both recall and transfer, and contrast analyses were conducted to determine the effects of context-dependency of seductive details on recall and transfer. The results indicated that there was no significant effect of context-dependency of seductive details on recall or transfer. The findings are discussed in the context of the related literature and directions for future research are suggested.

This thesis is aimed at developing a volume integral equation which 1) is well-posed; 2) leads to a symmetric coefficient matrix when solved by the method of moments when the object of interest is filled with reciprocal medium; 3) is applicable to a nonconformal mesh. Previous studies and developments in the method of moments solution of volume integral equations require a conformal mesh to discretize a penetrable object due to the mathematical constraints imposed on the basis and/or testing functions. In order to avoid any mathematical constraints on the basis and/or testing functions, we apply the gradient-gradient operator on the integral equation kernel, which is the free space Green’s function, instead of splitting it to operate on the basis and/or testing functions. This gives us the flexibility to choose piecewise constant functions for expansion and testing. Hence the mesh to discretize the object of interest need not be conformal. Moreover, the coefficient matrix is symmetric for a reciprocal medium due to the symmetry of the volume integral operators in the formulation. However, applying the gradient-gradient of the Green’s function leads to a hypersingular integral which needs to be regularized. In this study, we adopt a regularization scheme which adds and subtracts a function, which can be integrated analytically on the surface of a volume element, to the integral equation kernel. The numerical study demonstrates the well-posedness of the formulation. The analysis of penetrable structures has traditionally been carried out using partial differential equation methods due to the large computation time and memory requirements of integral equation methods. To alleviate this problem, this thesis extends the fast algorithm termed IE-FFT to the method of moments solution of nonconformal volume integral equations. Previous studies show that the IE-FFT algorithm reduces the computational time and memory requirement to O (N 1.5logN) and O (N 1.5), respectively, for surface integral equations to solve electromagnetic scattering problems where N is the number of unknowns. When the IE-FFT algorithm is applied to nonconformal volume integral equations, the computational complexity and memory requirement reduce to O (NlogN) and O (N), respectively.

Inflation was a common problem for developing countries in the 1970s and 1980s. From the beginning of the 21st century on, inflation is no longer as widespread as it used to be, but some few countries, like Turkey, continued to suffer from high inflation. Why have some developing countries become laggards in tackling the inflation problem, while most other countries stabilized their prices by 1990s? I argue that the answer can be found in socio-political factors as much as in economic factors. This dissertation strives to explain the persistence of inflation in developing countries with a socio-political approach. I suggest that persistent inflation cannot be explained solely by economic approaches. We also need to analyze the socio-political context of a country in order to understand why policymakers maintain inflationary policies and delay stabilization. This dissertation suggests that policymakers in some countries may experience greater difficulties in tackling inflation and face persistent inflation because of certain limitations, such as threats to national security, democracy, political instability, and proportional electoral system.This study compares the Turkish case with four other countries (Argentina, Brazil, Israel, and Mexico) to examine in detail whether and how social and political factors affect persistence of inflation. In addition to case studies, a statistical analysis of cross-national analysis is employed in order to get plausible explanations of persistent inflation. Many statistical analysis results support what is found in the case analyses. Findings suggest that international security concerns affect persistent inflation. High military expenses, which are necessary because of high threats to security, decrease the ability to eliminate inflation. Moreover, regime instability makes states less able to tackle the inflation problem and a consolidated democracy is the best political setting for price stabilization. Also, strong and stable governments are associated with less inflationary years. Electoral system and party system are relevant as well because they affect the strength and stability of the government. On the other hand, inequality and poverty do not seem to affect price stabilization.

This study is an exploratory and descriptive study of shopping malls in two cultures. The purpose of this dissertation is twofold: (1) to explore and describe the conditions of malls relevant to people's perception of space and their interactions with others; and (2) to investigate the relationship between variables such as type of perceived enclosure, density and lighting, and perceived spaciousness and crowding, and interpersonal distance. Four shopping malls in Turkey and the United States were selected for case studies. Based on users' subjective responses to openness and closeness, two areas inside each mall were defined where interviews and observations were conducted. During interviews, respondents were asked to rate the spaciousness and crowdedness of the open and closed areas. Density and lighting conditions of each area were measured. Total of 337 people responded to the questionnaires. Observations were employed with time-lapse photography technique to measure interpersonal distances between users in the areas where interviews took place. Total of 3072 distance measurements were made in all cases. The relationships between variables were tested by Spearman's correlation coefficients. Most of the analysis included descriptions with percentages. It was intended to develop hypotheses for the benefit of future research. The results were compared across two cultures and discussed in relation to the defined and measured conditions of mall areas. The description of the mall characteristics pointed to the both similarities and differences among layout, location, frequency and time of visit, activities, and users' definitions of areas. Overall comparisons and descriptions provided evidence about cross-cultural difference in interpersonal distance and perception of crowding, but not in perception of spaciousness. Most of the users in all cases perceived the areas spacious. Turkish mall users felt more crowded than American mall users, pairs in Turkish malls interacted closer than those in American malls, and male-female pairs interacted closer than male-male and female-female pairs.

The main goal of this thesis is to present the geometry and structural evolution of the Babadag fault zone, which is located at the southern margin of the Denizli Basin and separates metamorphic rocks in its footwall from sedimentary rocks in its hanging wall. The study also investigates the shear sense indicators that were found along the footwall rocks of the fault zone. The Babadag fault zone that controls the southern margin of the Denizli Basin is a steeply dipping normal fault. It contains two major step-over as displacement along the fault partitions westward. Deformation features in the Buyuk Menderes shear zone range from ductile-brittle and the early stage of the deformation during the extension was ductile. The fault rocks consisted ductile shear sense microstructures and brittle shear sense indicators, found in the fault rocks along the Babadag fault zone, indicate top to the north movement of the upper plate. These observations suggest to us that the prominent movement along the Babadag fault zone and its high-angle splays is top to the north.

To support the myriad of envisioned communication products of the future, there is a need to develop a network infrastructure that can provide larger bandwidth, with better control of quality of service (QoS). However, with increasing demand for applications running over packet networks, congestion at the intermediate nodes (e.g., routers and switches) can be a serious problem. Consequences include long delays, large delay variation and high packet loss rates. Different solutions requiring varying levels of modification to the currently used algorithms have been proposed both for responsive (e.g., TCP) and unresponsive (e.g., UDP) protocols. However, most of the solutions are either too complicated to implement in real life or not general enough to be applicable to an arbitrary network topology. In this thesis, we investigate two mechanisms - active queue management (AQM), and scheduling - that can improve QoS in the packet networks. AQM techniques attempt to prevent congestion and regulate the queue length by sending congestion signals (i.e., dropping and/or marking packets) in a proactive manner, which would eventually cause the senders to decrease their sending rates. We use an analytic model derived for TCP in the literature to develop an AQM scheme that not only controls the queue length at the intermediate nodes but also distributes the resources fairly between the users. We present two different schemes that have different levels of complexity and performance. We also propose a distributed networking scheme that improves the performance of our new AQM algorithms. Although AQM schemes work well with responsive protocols such as TCP, the performance degrades for unresponsive protocols since unresponsive protocols do not change their packet sending rate in response to the congestion notifications sent by the network. Scheduling algorithms can regulate both responsive and unresponsive flows and can also provide guarantees on some QoS parameters, such as latency and fairness. We propose a new scheduling algorithm that can guarantee a better latency and fairness bound than the previous schemes with a similar complexity. This new scheme uses different queues for each round to simplify the common sorting problem with the scheduling schemes. Also a new notion, virtual round, is used to time-stamp incoming packets.

The interactions of CO2 with coal were investigated under a set of conditions to determine the effects of the nature of the coal and the sequestration environment including parameters such as rank and moisture content of the coal, the temperature, pressure, and pH. A mathematical model was also developed to simulate the coal bed methane production and the CO2 sequestration processes. The excess adsorption and desorption isotherms of CO2 on eight Argonne Premium coal samples were measured using the volumetric method. The isotherms were found to be rectilinear and fit to the conventional adsorption model equations poorly due to the coal swelling. An adsorption isotherm equation was derived to account for the volumetric changes and significantly better fits were obtained. Upon drying, the volume of coals was determined to shrink, which was about 2% to 5% for medium and high rank coals, and up to 40% for the low rank coals. The swelling of coals during adsorption isotherm measurements in CO2 was estimated to be about the same as the shrinkage that occurred during the moisture loss. If the swelling was not included in the adsorption isotherm equation, the reported adsorption capacities and surface areas of the coals were overestimated by about 15%. The adsorption capacities of moisture-free Argonne coals were found to be about 2.2 ± 0.8 mmole/g-coal, daf basis and to be lower in wet coals. The isosteric heat of adsorption for CO2 on Argonne coals was estimated to be about 25±2 kJ/mole, regardless of the coal rank. The adsorption capacity of CO2 on the weak solutions of acid leached coals was higher than both the base leached and untreated coals, possibly due to the removal of ash content of the coals. The modeling results developed to simulate the CO2 injection process suggest that the CO2 can be injected at a rate of about 10*103 standard m3 per day. The injected CO2 will reach the production well, which is separated from the injection well by 826 m, in about 30 years. During this period, about 160*106 Sm3 of CO2 can be stored within a 2.14 (km)2 coal seam.

The purpose of this study was to inquire about the simultaneous coexistence of alternative and scientific conceptions in the domain of physics. This study was particularly motivated by several arguments put forward in opposition to the Conceptual Change Model. In the simplest form, these arguments state that people construct different domains of knowledge and different modes of perception in different situations. The following research questions were generated to inquire about this argument: (1) Do individuals keep their alternative conceptions after they have acquired scientific conceptions? (2) How are these different conceptions nested in their conceptual structure? (3) What kind of knowledge, skills, and reasoning are necessary to transfer scientific principles instead of alternative ones in the construction of a valid model? Two groups of participants were selected for this inquiry: one with minimal (non-physics group) and the other with high level of domain specific knowledge in physics (physics group). Data collection procedures were based on think-aloud and retrospective questioning. Analysis of the data collected from the non-physics group indicated that the nature of alternative conceptions is framed by two types of reasoning: reasoning by mental simulation and semiformal reasoning. Analysis of the data collected from the physics group revealed that mental images or scenes feeding reasoning by mental simulation had not disappeared after the acquisition of scientific conceptions. It was also evident that alternative principles feeding semiformal reasoning had not necessarily disappeared after the acquisition of scientific conceptions. It was explicitly noticed that although the participants compartmentalized reasoning by mental simulation and scientific (formal) reasoning, semiformal and scientific reasoning were intertwined in a way that the components of semiformal reasoning easily took their place among the components of scientific reasoning. In spite of the fact that the coexistence of multiple conceptions might obstruct the transfer of scientific conceptions in problem-solving situations, several factors stimulating the use of scientific conceptions were noticed explicitly. These factors were categorized as follows: (a) domain specific knowledge, (b) knowledge about the process of science, (c) awareness, and (d) context.