International Telemetering Conference Proceedings / October 23-26, 2000 / Town & Country Hotel and Conference Center, San Diego, California / NATO NAFAG Air Group IV (AG IV) established the NATO Advanced Data Storage Technical Support Team (NADS TST) to investigate the technology and to develop an interface Standardization Agreement (STANAG) for recording, storage, and exchange of imagery data. Government agencies and industry involved in these technologies are participating in this effort.

Following the discovery of graphene, 2D nanostructures have been noted for their potential in a range of high-impact applications, such as sensing, catalysis, and composite reinforcement. Liquid-phase exfoliation and chemical vapour deposition have been demonstrated and indicate the feasibility of mass-scale production. With the advent of mass-produced 2D nanostructures a key focus of research is to characterise these materials. This thesis is concerned with imaging and structural properties of the 2D nanomaterials, hexagonal boron nitride (h-BN), molybdenum disulfide (MoS₂), tungsten disulfide (WS₂), titanium disulfide (TiS₂) and hexabenzocoronene (HBC), produced via liquid phase exfoliation. HBC strictly speaking is not 2D nanomaterial, however, it can be viewed as transition molecule from benzene to graphene. The data used for characterisation is based primarily on electron diffraction and, in particular, aberration corrected annular dark field (ADF) scanning transmission electron microscopy (STEM). The incoherent nature of ADF STEM provides direct atomic imaging without the contrast reversals upon focus changes seen in conventional high-resolution transmission electron microscopy (HRTEM). The main structural feature investigated in this thesis was the stacking sequences in few-layers h-BN, MoS₂, WS₂ and TiS₂. Simple stacking (AAA) can be distinguished from Bernal (ABA) and rhombohedral (ABC) on the basis of intensity ratio, I_{10̅10}/I_{11̅20} , in diffraction patterns and indirectly in HRTEM images. Nonetheless acquisition of the diffraction patterns suitable for analysis can be challenging due to the sample issues. Non-bulk stacking sequences were reliably confirmed for all above 2D nanomaterials on the basis of atomically resolved ADF STEM. 20 h-BN, 28 MoS₂, 5 WS₂ and 6 TiS₂ nanoflakes were imaged and analysed. Amongst them 2 h-BN, 9 MoS2, 4 WS2 and 1 TiS2 nanoflakes displayed non-bulk stacking. Hence, it appears that 2D WS2 has the greatest affinity for non-bulk stacking. Finally, an interesting structural transformation was observed in HBC molecules. Under the influence of electron beam HBC agglomerates were transformed into crystalline phase with 90^o symmetry.

Botnets are a pervasive threat to the Internet and its inhabitants. A botnet is a collection of infected machines that receive commands from the botmaster, a person, group or nation- state, to perform malicious actions. Instead of “cleaning” individual infections, one can sever the method of communication between a botmaster and her zombies by attempting a botnet takedown, which contains the botnet and its malicious actions. Unfortunately, takedowns are currently performed without technical rigor nor are there automated and independent means to measure success or assist in performing them. This dissertation focuses on understanding the criminal infrastructure that enables communication between a botmaster and her zombies in order to measure attempts at, and to perform, successful takedowns. We show that by interrogating malware and performing large-scale analysis of passively collected network data, we can measure if a past botnet takedown was successful and use the same techniques to perform more comprehensive takedowns in the future.

The fluoride-salt-cooled high-temperature reactor (FHR) is a novel reactor design benefitting from passive safety features, high operating temperatures with corresponding high conversion efficiency, to name a few key features. The fuel is a layered graphite plank configuration containing enriched uranium oxycarbide (UCO) tri-structural isotropic (TRISO) fuel particles. Fuel cycle cost (FCC) models have been used to analyze and optimize fuel plate thicknesses, enrichment, and packing fraction as well as to gauge the economic competitiveness of this reactor design. Since the development of the initial FCC model, many corrections and modifications have been identified that will make the model more accurate. These modifications relate to corrections made to the neutronic simulations and the need for a more accurate fabrication costs estimate. The former pertains to a MC Dancoff factor that corrects for fuel particle neutron shadowing that occurs for double-heterogeneous fuels in multi-group calculations. The latter involves a detailed look at the fuel fabrication process to properly account for material, manufacturing, and quality assurance cost components and how they relate to the heavy metal loading in a FHR fuel plank. It was found that the fabrication cost may be a more significant portion of the total FCC than was initially attributed. TRISO manufacturing cost and heavy metal loading via packing fraction were key factors in total fabrication cost. This study evaluated how much neutronic and fabrication cost corrections can change the FCC model, optimum fuel element parameters, and the economic feasibility of the reactor design.

ENGLISH ABSTRACT: In today’s hi-tech global economy the fields of science, technology and engineering are becoming increasingly and undeniably central to economic growth and competitiveness, and will provide many future jobs. Qualifications in Mathematics are crucial gateways to further education and will provide access to the Science, Technology, Engineering and Mathematics (STEM) industries. This study focuses on the optional course in Mathematics, called Advanced Programme Mathematics (APM), which is offered and assessed by the Independent Examination Board in the final three years of high school in South Africa. At present, the South African school system does not adequately prepare students for the transition from school to university Mathematics, and APM has been designed to address this gap. The research question set by this study is: To what extent does the APM course succeed in preparing learners for the rigour of first-year Mathematics in the STEM university programmes? The sample group of 439 students was selected from the 2013 cohort of first-year Mathematics students at Stellenbosch University. First, an analysis of the relevant curricula was undertaken, and then an empirical investigation was done to determine the differences in performance between first and second semester examinations of first-year university Mathematics students who took APM, and those who did not. This was followed by an investigation by means of a questionnaire into the perceptions of students on how effective APM was in easing the transition from school to university Mathematics. The research was designed according to the Framework for an Integrated Methodology (FraIM) of Plowright (2011). From an extensive international literature study, it appears that APM is definitely a predictor of post-secondary success. Since no formal research has been recorded to support this claim, this study aims to provide a sound answer to whether APM is advantageous. The effect size results of this study show that APM marks of students explain 68% of the achievement in first-semester university Mathematics when combined with NSC Mathematics marks in a general regression model. There is a significant difference between the marks of students who took APM and those who did not in first-semester university Mathematics, specifically across the National Senior Certificate (NSC) Mathematics mark categories of 80-100%. APM course-taking leads to confidence in Mathematics, which combined with good domain knowledge of calculus, ease the transition from school to university Mathematics. The study recommends that not only students who intend pursuing a career in the STEM industries should take the APM course, but also those who intend to apply for admission to any other tertiary studies, as the cognitive and other skills provided by APM will give them the required edge to perform well in higher education. Schools are called upon to provide access to APM for mathematically gifted students, and teachers and guidance counsellors should encourage learners to enrol for AMP. This will enable them to share in the manifold academic and personal benefits accruing from the course, and to help alleviate the critical shortage of graduates in careers requiring a strong Mathematics background in South Africa. / AFRIKAANSE OPSOMMING: In die hoë-tegnologie-wêreldekonomie van vandag word die gebiede van wetenskap, tegnologie en ingenieurswese toenemend en onmiskenbaar die kern van ekonomiese groei en mededingendheid wat in die toekoms baie werkgeleenthede sal bied. Kwalifikasies in Wiskunde open beslis baie deure na verdere opleiding en verleen toegang tot die Wetenskap-, Tegnologie- Ingenieurswese- en Wiskunde-industrieë. Hierdie studie fokus op die opsionele kursus in Wiskunde, genaamd Gevorderde Program Wiskunde (GPW), wat deur die Onafhanklike Eksamenraad aangebied en geassesseer word in die laaste drie jaar van hoërskoolonderrig in Suid-Afrika. Tans berei die Suid-Afrikaanse skoolstelsel nie studente genoegsaam voor vir die oorgang van skool- na universiteitswiskunde nie en GPW is ontwerp om hierdie gaping te oorbrug. Die navorsingsvraag wat hierdie studie stel, is: In watter mate slaag die GPW-kursus daarin om leerders voor te berei vir die streng vereistes van eerstejaar-Wiskunde in die Wetenskap-, Tegnologie- Ingenieurswese- en Wiskunde-universiteitsprogramme? Die toetsgroep van 436 studente is gekies uit die 2013-groep eerstejaar-Wiskundestudente aan Stellenbosch Universiteit. Aanvanklik is ᾽n analise van die relevante leerplanne onderneem, waarna ᾽n empiriese ondersoek gedoen is om die verskille in prestasie in die eerste en tweede semester eksamens vas te stel tussen eerstejaar-Wiskundestudente op universiteit wat wel GPW geneem het en diegene wat dit nie geneem het nie. Dit is gevolg deur ᾽n ondersoek deur middel van ᾽n vraelys na die persepsies van studente oor hoe effektief GPW was om die oorgang van skool- na universiteitswiskunde te vergemaklik. Die navorsing is ontwerp op grond van ‘n model vir ‘n geïntegreerde metodologie van Plowright (2011). Dit blyk uit ᾽n uitgebreide studie van internasionale literatuur dat GPW definitief ᾽n voorspeller van post-sekondêre sukses is. Aangesien geen formele navorsing om hierdie aanspraak te ondersteun nog op skrif gestel is nie, poog hierdie studie om ᾽n deurdagte antwoord te verskaf op die vraag of GPW wel tot voordeel van studente is. Die effek grootte resultate van hierdie studie dui aan dat die GPW-punte van studente 68% van prestasie in Wiskunde in die eerste semester op universiteit verduidelik as dit in ᾽n algemene regressiemodel met die Nasionale Senior Sertifikaat (NSS) punte gekombineer word. Daar is ᾽n beduidende verskil tussen die Wiskundepunte van studente wat GPW geneem het en diegene wat dit nie geneem het nie in die eerste semester op universiteit, veral in die NSS-Wiskundepuntekategorieë van 80-100%. Om die GPW-kursus te neem, lei tot selfvertroue in Wiskunde, wat saam met ᾽n goeie kennis van die Differensiaalrekening-domein, die oorgang van Wiskunde vanaf skoolvlak na universiteitsvlak vergemaklik. Op grond van die studie beveel die navorser aan dat nie slegs studente wat ᾽n loopbaan in Wetenskap-, Tegnologie- Ingenieurswese- en Wiskunde-rigtings wil volg, die GPW-kursus behoort te volg nie, maar ook diegene wat vir toelating tot enige ander tersiêre studie wil aansoek doen, aangesien die kognitiewe en ander vaardighede wat GPW ontwikkel, hulle die nodige voorsprong sal bied om goed te vaar in verdere studie. Skole word aangemoedig om toegang tot GPW aan wiskundig begaafde leerlinge te verskaf en onderwysers en loopbaanraadgewers behoort leerlinge aan te moedig om vir GPW in te skryf. Sodoende kan hulle deel in die vele akademiese en persoonlike voordele wat die kursus bied, en help om die kritieke tekort aan gegradueerdes in die studierigtings waar ‘n sterk Wiskunde agtergrond ‘n vereiste is, te help verlig.

Every year, new trace chemicals are detected in natural waters as well as treated wastewater effluents all over the world. Public health and environmental concerns have driven the development of new technologies to treat water and eliminate chemicals that may pose risk to humans and wildlife. This work presents a detailed statistical analysis on the removal of some of the most widely occurring chemicals of emerging concern in wastewater based on information available in the literature. Results show that existing water treatment processes only partially eliminate most of these contaminants. Advanced oxidation processes (AOPs) are some of the technologies that have shown the most promising results for the removal of recalcitrant organics in water. Hydrogen peroxide photolysis (UV/H₂O₂) and Fenton’s reaction are some examples of AOPs that use hydroxyl radicals to oxidize organics. The kinetics of UV/H₂O₂ and Fenton’s reaction were studied from the experimental and mathematical points of view. Comprehensive models with no adjustable parameters successfully accounted for radical initiation via photolysis of H₂O₂ or radical initiation via Fenton’s mechanism; reaction of organic targets such as p-cresol and nonylphenol with hydroxyl radicals; and recombination mechanisms, as well as changes in solution pH due to evolution of carbon dioxide because of target mineralization. The presence of radical scavengers was successfully handled by the models, suggesting that they can be generalized to the treatment of complex matrices. The UV/H₂O₂ model was also extended to solar catalyzed applications. Using an atmospheric solar irradiation model (SMART) and data from the Giovanni-NASA online database, ground-level solar spectral irradiance were obtained and used as model inputs. The kinetic model provided an excellent fit to experimental results obtained with p-cresol and fluorescein targets using no fitted parameters. The UV/H₂O₂ process was also studied in commercial flow-through UV reactors with monochromatic and polychromatic light sources. Organic targets of interest such as pcresol can be degraded effectively in these reactors at relatively low peroxide concentrations. Results with wastewater effluents suggest that these commercial reactors can be used for AOP tertiary treatment as a way to reduce dissolved organic matter and eliminate potential harmful chemicals present in the water.

Nursing care of patients with advanced cancer is challenging because it touches many dimensions of a patient’s life. The study of spiritual pain is relatively new although potentially very important in understanding how to help patients with advanced cancer achieve a sense of well-being. The purpose of this pilot study was to increase scientific knowledge from the participants‟ perspectives about experiences of spiritual pain and physical pain, and identify correlates of well-being from the participants‟ own perspectives in the context of advanced cancer. Four research questions were examined in this study: 1. What is the relationship between physical pain and spiritual pain, as perceived by participants who have advanced cancer? 2. What is the relationship between spiritual pain and existential well-being, as perceived by participants who have advanced cancer? 3. What is the relationship between spiritual pain and physical pain in the context of the demographic and health-related variables of age, gender, years of education, and months since diagnosis? 4. What factors do participants with advanced cancer identify as important to their existential well-being? A descriptive correlational design was used to study the research questions in a convenience sample of 30 adult participants from an outpatient oncology clinic in Southern Arizona. Quantitative data were obtained through interviews using the Providence Saint Vincent Medical Center Pastoral staff’s Spiritual Pain Assessment Tool and Paloutzian and Ellison’s (2009) Existential Well-Being Scale, and a Physical Pain Rating scale along with a demographic and health-related form. Qualitative data were also obtained from the participants. Descriptive, correlational, and content analyses generated results of a significant relationship between Spiritual Pain and Existential Well-Being, and a non-significant relationship between Physical Pain and Spiritual Pain. The following themes (with the first three being most frequently mentioned) were identified as important to the participants‟ well-being during their experience of advanced cancer: Meaningful activity, family and friends, and spiritual aspects, followed by health/nutrition, symptom management, and finances. Results warrant continued research into spiritual pain as it relates to existential well-being in persons with advanced cancer

The aim of this study is to implement the model predictive control in order to optimally control the power output of a Brayton cycle based power plant. Other control strategies have been tried but there still exists the need for better performance. In real systems, a number of constraints exist. Incorporating these into the control design is no trivial task. Unlike in most control strategies, model predictive control allows the designer to explicitly incorporate constraints in its formulation. The original design of the PBMR power plant is considered. It uses helium gas as the working fluid. The power output of the system can be controlled by manipulating the helium inventory to the gas cycle. A linear model of the power plant, modelled in Simulink® is used. This linear model is used as an evaluation platform for the control strategy. The helium inventory is manipulated by means of actuators which use values generated by the controller. The controller computes these values by minimizing the cost of future outputs over a finite horizon in the presence of constraints. The dynamic response of the system is used to tune the controller. The power output performance at different configurations of the controller under perfect conditions and with disturbances is examined. The best configuration is used resulting in an optimal power control system for the Brayton cycle based power plant. Results showed that the method employed can be used to implement the control strategy. Furthermore, better performance can be realised with model predictive control. / Thesis (M.Ing. (Electrical and Electronic Engineering))--North-West University, Potchefstroom Campus, 2012

Composite materials have become viable alternatives to traditional engineering materials for many different product categories. Liquid transfer moulding (LTM) processes, specifically resin transfer moulding (RTM), is a cost-effective manufacturing technique for creating high performance composite parts. These parts can be tailor-made to their specific application by optimizing the properties of the textile preform. Preforms which require little or no further assembly work and are close to the shape of the final part are critical to obtaining high quality parts while simultaneously reducing labour and costs associated with other composite manufacturing techniques. One type of fabric which is well suited for near-net- shape preforms is stitched non-crimp fabrics. These fabrics offer very high in-plane strength and stiffness while also having increased resistance to delamination. Manufacturing parts from these dry preforms typically involves long-scale fluid flow through both open channels and porous fibre bundles. This thesis documents and analyzes the flow of fluid through preforms manufactured from non-crimp fabrics featuring through-thickness stitches. The objective of this research is to determine the effect of this type of stitch on the RTM injection process. All of the tests used preforms with fibre volume fractions representative of primary and secondary structural parts. A series of trials was conducted using different fibre materials, flow rates, fibre volumes fractions, and degrees of fibre consolidation. All of the trials were conducted for cases similar to RTM. Consolidation of the fibres showed improvements to both the thoroughness of the filling and to the fibre volume fraction. Experimentally determined permeability data was shown to trend well with simple models and precision of the permeability data was comparable to values presented by other authors who studied fabrics which did not feature the through-thickness stitches.

This Study investigates the effectiveness of a new Instructional Design model for using advanced multimedia in the teaching and learning of photography at university level in Kingdom of Bahrain. A preliminary study revealed that the central problems faced by students are learning key technical aspects of photography coupled with insufficient resources and high student teachers ratio. Advanced multimedia was proposed as an effective tool for teaching and learning photography. A critical review and analysis of existing e-learning resources revealed that such technology might help in teaching and learning, especially subjects that need experience with real instruments like cameras. Through reference to the ASSURE model, Laurillard's conversational model, and insights from Steuer's Classification model, the researcher developed a new instructional design model for using advanced multimedia in photography education [AMPE]. This was field tested in University photography teaching. For the evaluation of the AMPE model a mixed-model design was used, combining quantitative and qualitative methods. In a quantitative evaluation, effectiveness in learning was estimated from the student achievement in a test. A comparison of the opinions of the two groups of students in a specially constructed questionnaire measuring their views of the respective teaching and learning methods was also applied. Finally engagement and enjoyment in learning in the two groups of students were also assessed through questionnaire. The participants‘comments, opinions, and suggestions were obtained through open-ended questions in the questionnaire. The study found that advanced multimedia enhances effectiveness, engagement, and enjoyment in learning photography. The instructional model and associated ―virtual camera‖ seems to be a suitable solution for the lack of real cameras in the classroom environment, and can help in the teaching of difficult technical photographic knowledge in an efficient and practical manner.