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Sodium-ion batteries (SIBs) are rechargeable batteries analogous to lithium-ion batteries but use sodium ions (Na+) as the charge carriers. They are considered a promising alternative for lithium-ion batteries (LIBs) in renewable large-scale energy storage applications due to their similar electrochemical mechanisms and abundant sodium resources. Two-dimensional (2D) materials, with atomic or molecular thickness and large lateral lengths, have emerged as important functional materials due to their unique structures and excellent properties. These 2D nanosheets have been highly studied as sodium-ion battery anodes. They have large interlayer spacing, which can effectively buffer the big volume expansion and prevent electrode collapse during the charge-discharge process. Different strategies such as preparing composites, heterostructures, expanded structures, and chemical functionalization can greatly improve cycling stability and lead to high reversible capacity. In this dissertation, state-of-the-art SIB based on 2D material electrodes will be presented. In particular, Tin-based 2D materials and laser-scribed graphene anodes are discussed. Different strategies involving engineering both synthesis methods, intrinsic properties of materials, and device architecture are used to optimize the battery performance.

A thesis submitted to the Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy, Department of Pharmacy and Pharmacology, University of the Witwatersrand, Johannesburg, 2017. / Numerous pharmaceutical solid dosage form manufacturing techniques have emerged over the years and among them, 3D-Printing (3DP) has emerged as a highly attractive and versatile approach. 3DP is a cutting edge technology set to expand and revolutionize tablet manufacturing among various other applications in industry. The study reported in this thesis focuses on developing a humic acid-polyquaternium-10 (HA-PQ10) 3D-Printable ink for the delivery of three anti-HIV bioactives, efavirenz (EFV), tenofovir (TDF) and emtricitabine (FTC). HA was strategically employed based on its capability of entrapping both hydrophilic and hydrophobic drugs. PQ10 contributed towards the system’s swellability in aqueous media. The HA-PQ10 PEC was responsible for retarding drug release therefore it behaved as a drug reservoir. Validation of HA-PQ10 complexation was carried out by synthesizing the HA-PQ10 polyelectrolyte complex (PEC) in aqueous media at pH 6, 7 and 8. The complexation yielded fibrilla and porous PECs. The PEC formation was attributed to ionic interactions between the quaternary ammonium centres (PQ10) and carboxylic groups (HA). The PECs were determined to be amorphous in nature and exhibited good biocompatibility when tested for cytotoxicity in human adenocarcinoma cell line (Caco2). The model drug, efavirenz (EFV) was loaded into HA-PQ10 using the complexation-precipitation (C-P) technique. The resultant EFV-loaded HA-PQ10 was compared to benchtop extrudates manufactured using the extrusion-spheronization (E-S) process. Assessment of the EFV saturation solubility and intestinal permeability showed EFV solubility and permeability enhancement of 14.14±2.81% and 61.24±6.92% respectively. The properties were compared to those of a marketed comparator product. Loading RTV into the optimized HA-PQ10 further validated the solubility and permeability enhancing properties in the BCS class IV drug as well. The extrudates performed superiorly compared to the formulation synthesized by C-P. The E-S technique was utilized to optimize HA-PQ10 based on drug release and intestinal permeation enhancement. The optimal HA-PQ10 was employed for 3DP of EFV-loaded HA-PQ10 into an oral tablet formulation. It was imperative to add cellulose acetate phthalate (CAP) to enhance the 3D-Printability of the HA-PQ10. CAP made the synthesized delivery system pH responsive and drug release results showed that most of the release occurred under intestinal conditions. The EFV-loaded 3DP tablet was compared to a tablet synthesized by direct compression. 3DP was more porous, less dense and more swellable than the direct compression tablet. These remarkable differences were attributed to the tableting method. 3DP leads to the formation of solid bridges between particles as the sludge (ink) undergoes extrusion and drying process. The direct compression technique involves axial powder compaction at high pressures which force particles to interact through Van der Waals forces or hydrogen bond formation. High drug loading of EFV was achieved and the tablet was further optimized to manufacture the ‘controlled release tritherapeutic tablet’, CRTT, a fixed dose combination (FDC) consisting of EFV, TDF and FTC. In vivo studies were conducted in large white pigs and CRTT absorption was compared to a marketed FDC, Atripla®. There was sustained release of EFV, TDF and FTC from CRTT and this was validated by the long residence times determined from pharmacokinetic analysis. EFV was maintained within the therapeutic index of the drug during the 24 hour study. Through this study, 3DP proved to be a technology with potential for manufacturing novel formulations. As more research is underway in the 3DP field, it can only be appreciated that its scope of use will continue to grow and restructure pharmaceutical manufacturing processes. / LG2018

The effects of fin-leading-edge radius and sweep angle on peak heating rates due to shock-shock interactions were investigated in the NASA Langley Research Center 20-inch Mach 6 Air Tunnel.  The fin model leading edges, which represent cylindrical leading edges or struts on hypersonic vehicles, were varied from 0.25 inches to 0.75 inches in radius.  A 9° wedge generated a planar oblique shock at 16.7° to the flow that intersected the fin bow shock, producing a shock-shock interaction that impinged on the fin leading edge.  The fin angle of attack was varied from 0° (normal to the free-stream) to 15° and 25° swept forward.  Global temperature data was obtained from the surface of the fused silica fins through phosphor thermography.  Metal oil flow models with the same geometries as the fused silica models were used to visualize the streamline patterns for each angle of attack.  High-speed zoom-schlieren videos were recorded to show the features and temporal unsteadiness of the shock-shock interactions.  The temperature data were analyzed using one-dimensional semi-infinite as well as one- and two-dimensional finite-volume methods to determine the proper heat transfer analysis approach to minimize errors from lateral heat conduction due to the presence of strong surface temperature gradients induced by the shock interactions.  The general trends in the leading-edge heat transfer behavior were similar for the three shock-shock interactions, respectively, between the test articles with varying leading-edge radius.  The dimensional peak heat transfer coefficient augmentation increased with decreasing leading-edge radius.  The dimensional peak heat transfer output from the two-dimensional code was about 20% higher than the value from a standard, semi-infinite one-dimensional method. / Master of Science

Dans cette thèse, nous explorons des structures intermédiaires ainsi que le rapport entre eux et des algorithmes utilisés dans le contexte du rendu photoréaliste (RP) et non photoréaliste (RNP). Nous présentons des nouvelles structures pour le rendu et l'utilisation alternative des structures existantes. Nous présentons trois contributions principales dans les domaines RP et RNP: Nous montrons une méthode pour la génération des images stylisées noir et blanc. Notre approche est inspirée par des bandes dessinées, utilisant l'apparence et la géometrie dans une formulation d'énérgie basée sur un graphe 2D. En contrôlant les énérgies, l'utilisateur peut générer des images de differents styles et représentations. Dans le deuxième travail, nous proposons une nouvelle méthode pour la paramétrisation temporellement cohérente des lignes animées pour la texturisation. Nous introduisons une structure spatiotemporelle et une formulation d'énérgie permettant une paramétrisation globalement optimale. La formulation par une énérgie donne un contrôle important et simple sur le résultat. Finalement, nous présentons une extension sur une méthode de l'illumination globale (PBGI) utilisée dans la production de films au cours des dernières années. Notre extension effectue une compression par quantification de données générées par l'algorithme original. Le coût ni de memoire ni de temps excède considérablement celui de la méthode d'origin et permet ainsi le rendu des scènes plus grande. L'utilisateur a un contrôle facile du facteur et de la qualité de compression. Nous proposons un nombre d'extensions ainsi que des augmentations potentielles pour les méthodes présentées. / In this thesis, we explore intermediary structures and their relationship to the employed algorithms in the context of photorealistic (PR) and non-photorealistic (NPR) rendering. We present new structures for rendering as well as new uses for existing structures. We present three original contributions in the NPR and PR domain: First, we present binary shading, a method to generate stylized black and white images, inspired by comic artists, using appearance and geometry in a graph-based energy formulation. The user can control the algorithm to generate images of different styles and representations. The second work allows the temporally coherent parameterization of line animations for texturing purposes. We introduce a spatio-temporal structure over the input data and an energy formulation for a globally optimal parameterization. Similar to the work on binary shading, the energy formulation provides a an important and simple control over the output. Finally, we present an extension to Point-based Global Illumination, a method used extensively in movie production during the last years. Our work allows compressing the data generated by the original algorithm using quantification. It is memory-efficient and has only a neglegible time overhead while enabling the rendering of larger scenes. The user can easily control the strength and quality of the compression. We also propose a number of possible extensions and improvements to the methods presented in the thesis.

The geometry and mineralization features of small left-lateral strike-slip faults and associated fractures in Lake Edison Granodiorite of the central Sierra Nevada, California, were examined in order to model the three-dimensional structure of strike-slip faults. These faults, which are reactivated joints, were also examined to determine fault sizes, starting joint size, and evidence for fluid flow. The associated secondary fractures are usually found in the dilational quadrants of fault-tip regions. The longest fault-segment trace is 32.14 m; the longest joint trace is 22 m. The joint population length (l) is represented by a power-law distribution (l-n) and it is l-1.22. The fault-segment distributions are l-0.23~0.79, and the compiled fault-segment distribution is l-1.18. The data on fracture and fault spacing, along with the joint power-law distribution, will aid in the simulation and analysis of fault evolution. The splay-fracture traced in the faults are linear at depth and the average splay-fracture angle is 39° ± 13°. The dihedral angle of the splay plane and fault plane ranges from 20° to 65°. There is a high concentration of splay fractures near the fault. As distance increases perpendicular form the fault, the splay-fracture spacing increases and splay-fracture frequency decreases. The splay tracelength distributions have a high short tracelength concentration with a rapid decrease of long tracelengths. The maximum tracelength of multiple splay-fracture groups is restricted by their distance orthogonal to the fault trace. The three-dimensional relationship between the splay-fracture plane and fault plane can be inferred from these data. When present, mineralized quartz appears largely as lenses and few as single continuous veins along the faults. No consistent pattern exists between fault displacement and the locations and dimensions of quartz cavities. There is no visible damage zone near the fault termination or around the faults. Microstructures in the fault zone consist of cataclasites and patchy gouges, and zones of dynamically recrystallized fault walls. The three-dimensional geometry, along with quartz cavity distribution and thin section analysis, has led to the conclusion that fluid migrates vertically among the faults and fractures.

Indiana University-Purdue University Indianapolis (IUPUI) / Too few studies relating to motivation and wellness have targeted the NCAA Division II student-athlete (SA) population. PURPOSES: To examine differences in SAs’ sport motivation (SM) types over three time points as well as multi-dimensional wellness (MDW) levels in SAs during one time point. METHODS: Overall, 530 Division II SAs (nmales = 355, nfemales = 175) with an overall age range of 18 to 23 (M = 19.40, SD = 1.33) from 21 teams voluntarily completed the 18-item Self-Determination Theory-based SM Scale II used to measure six motivation types, the 45-item MDW Inventory used to measure nine wellness dimensions, and a demographics questionnaire. Repeated measures Analyses of Variance (ANOVA) and 2x2x3 Mixed ANOVAs were used to analyze SM types while a multivariate ANOVA was used to analyze MDW with an alpha level of 0.05 set for statistical significance. RESULTS: Analyses demonstrated statistically significant differences in SM types over time (p = .05), interactions and differences in SM types between interactive/coactive and male/female SAs (p = .05), and interactions and differences in MDW levels between male/female SAs and SAs who completed/did not complete a college wellness course (p = .05). CONCLUSIONS: Findings suggested that autonomous-based SM types decreased over time whereas amotivation increased over time indicating possible athlete burnout. Interactive and female SAs showed similarities also representative of athlete burnout. SAs who completed the MDW course demonstrated higher physical wellness exercise scores than SAs who did not. Female SAs had higher means in five wellness dimensions when compared to male SAs. SAs who completed the course showed higher means for seven wellness dimensions versus SAs who did not. Further research should ensue to better understand motivation and wellness on a national scale examining Division I, II and III and NAIA athletes in order to provide more generalizable results.

Indiana University-Purdue University Indianapolis (IUPUI) / A significant hurdle for analyzing big data is the lack of effective technology and statistical inference methods. A popular approach for analyzing data with large sample is subsampling. Many subsampling probabilities have been introduced in literature (Ma, \emph{et al.}, 2015) for linear model. In this dissertation, we focus on generalized estimating equations (GEE) with big data and derive the asymptotic normality for the estimator without resampling and estimator with resampling. We also give the asymptotic representation of the bias of estimator without resampling and estimator with resampling. we show that bias becomes significant when the data is of high-dimensional. We also present a novel subsampling method called A-optimal which is derived by minimizing the trace of some dispersion matrices (Peng and Tan, 2018). We derive the asymptotic normality of the estimator based on A-optimal subsampling methods. We conduct extensive simulations on large sample data with high dimension to evaluate the performance of our proposed methods using MSE as a criterion. High dimensional data are further investigated and we show through simulations that minimizing the asymptotic variance does not imply minimizing the MSE as bias not negligible. We apply our proposed subsampling method to analyze a real data set, gas sensor data which has more than four millions data points. In both simulations and real data analysis, our A-optimal method outperform the traditional uniform subsampling method.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18275号 / 工博第3867号 / 新制||工||1593(附属図書館) / 31133 / 京都大学大学院工学研究科原子核工学専攻 / (主査)教授 福山 淳, 教授 功刀 資彰, 准教授 村上 定義 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第18402号 / 情博第517号 / 新制||情||91(附属図書館) / 31260 / 京都大学大学院情報学研究科複雑系科学専攻 / (主査)教授 山本 裕, 教授 西村 直志, 教授 太田 快人 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM