Utilization of natural gas in remote locations necessitates on-site conversion of methane into liquid fuels or high value products. The first step in forming high value products is the production of ethylene and acetylene. Non-thermal plasmas, due to their unique nonequilibrium characteristics, offer advantages over traditional methods of methane reforming. Different kinds of non-thermal plasmas are being investigated for methane reforming. Parameters of these processes like flow rate, discharge size, temperature and other variables determine efficiency of conversion. An efficient process is identified by a high yield and low specific energy of production for the desired product. A study of previous work reveals that higher energy density systems are more efficient for methane conversion to higher hydrocarbons as compared to low energy density systems. Some of the best results were found to be in the regime of warm discharges. Thermal equilibrium studies indicate that higher yields of ethylene are possible with an optimal control of reaction kinetics and fast quenching. With this idea, two different glow discharge reactor systems are designed and constructed for investigation of methane reforming. A counter flow micro plasma discharge system was used to investigate the trends of methane reforming products and the control parameters were optimized to get best possible ethylene yields while minimizing its specific energy. Later a magnetic glow discharge system is used and better results are obtained. Energy costs lower than thermal equilibrium calculations were achieved with magnetic glow discharge systems for both ethylene and acetylene. Yields are obtained from measurements of product concentrations using gas chromatography and power measurements are done using oscilloscope. Energy balance and mass balances are performed for product measurement accuracy and carbon deposition calculations. Carbon deposition is minimized through control of the temperature and residence time conditions in magnetic glow discharges. Ethylene production is observed to have lower specific energies at higher powers and lower flow rates in both reactors. An ethylene selectivity of 40 percent is achieved at an energy cost of 458MJ/Kg and an input energy cost of 5 MJ/Kg of methane.

All computer simulation models require some form of initialization before their outputs can be considered meaningful. Simulation models are typically initialized in a particular, often "empty" state and therefore must be "warmed-up" for an unknown amount of simulation time before reaching a "quasi-steady-state" representative of the systems' performance. The portion of the output series that is influenced by the arbitrary initialization is referred to as the initial transient and is a widely recognized problem in simulation analysis. Although several methods exist for removing the initial transient, there are no methods that perform well in all applications. This research evaluates the effectiveness of several techniques for reducing initialization bias from simulations using the commercial transportation simulation model VISSIM®. The three methods ultimately selected for evaluation are Welch's Method, the Marginal Standard Error Rule (MSER) and the Volume Balancing Method currently being used by the CORSIM model. Three model instances - a single intersection, a corridor, and a large network - were created to analyze the length of the initial transient for varying scenarios, under high and low demand scenarios. After presenting the results of each initialization method, advantages and criticisms of each are discussed as well as issues that arose during the implementation. The results for estimation of the extent of the initial transient are compared across each method and across the varying model sizes and volume levels. Based on the results of this study, Welch's Method is recommended based on is consistency and ease of implementation.

In this thesis, the Mechanical properties of polypropylene yarn of outer protection layer on Submarine High Voltage Cable, twisted around submarine cable,is determined on various conditions at ABB Company. In the first step, tensile tests are done with polypropylene yarn specimens with and without Bitumen at Room temperature. In the second step,tensile tests are done with polypropylene yarn specimens with and without Bitumen and with knotted polypropylene yarn namely: the Fishermen’s knot, the Weaver’s knot, the Square knot and the Overhand knot at Warm Condition (60˚c) and Cold Condition(-5˚c). In the final step,it is proposed to obtain numerical solution using FEM analysis with ABAQUS Software to obtain the hoop stress , the yarn stresses from twisting cable and analyzing of the cylindrical buckling in the buckling torsion and buckling bending on the outer layer of submarine cable with polypropylene material that is mixed with Bitumen.

Why do people work in the voluntary sector? Is the sector distinct, with characteristics that differentiate it from the private and public sectors? Is it important to consider the existence of the so-called ‘third sector’ when analysing behaviour in the labour market? Is altruism really an important motivation for workers in this sector? This dissertation is concerned specifically with the labour market in the voluntary sector: that is, workers who are the paid employees of independent nonprofit organisations. Using a large, national dataset, we explore empirically the predictions of the economic theory of voluntary organisations. In particular, is there evidence for a ‘warm glow’, the extra utility that workers receive for working towards a goal that they share with their employer? Does this glow exist, and is it brighter in the voluntary sector? We examine in turn sector differences in wages, working hours, and find evidence that employment in the voluntary sector is significantly different in some characteristics from both the private and public sectors. The main economic theories of voluntary sector wage-setting rely on some formulation of ‘warm glow’ utility or intrinsic motivation derived from working for an organisation with a mission shared by motivated employees. This leads to a prediction of lower wages in the voluntary sector. The empirical findings in the existing literature have focussed on US data, and the results have been mixed. Using pooled cross-sectional and panel datasets based on UK employment data between 1997 and 2007, we show that there is some evidence of warm-glow wage discounts in the sector for male workers, but that these wage differences have been eroded as the sector has grown. Although there is not a significant sector wage difference found for women, there is evidence that they have also experienced faster wage growth in the voluntary sector than the private. There are significant sector differences in working hours within the Health & Social Work industries, particularly in overtime working. Workers in the voluntary sector work more hours of unpaid overtime, whilst those in the private sector work more hours of paid overtime. Controlling for overtime hours has a significant effect on sector wage differentials. In particular, accounting for unpaid overtime results in evidence of a warm-glow wage discount for female workers. We analyse this data at a time when the sector has been growing dramatically, driven by government policy to reform public services. Our findings suggest that this policy has had unintended consequences for the voluntary sector labour market.

The Vehicle Routing Problem (VRP) is a classical problem in logistics that has been well studied by the operations research and transportation science communities. VRPs are defined as follows. Given a transportation network with a depot, a set of pickup or delivery locations, and a set of vehicles to service these locations: find a collection of routes starting and ending at the depot, such that (i) the customer's demand at a node is satisfied by exactly one vehicle, (ii) the total demand satisfied by a vehicle does not exceed its capacity, and (iii) the total distance traveled by the vehicles is minimized. This problem is especially hard to solve because of the presence of sub--tours, which can be exponential in number. In this dissertation, a special case of the VRP is considered -- where the underlying network has a tree structure (TVRP). Such tree structures are found in rural areas, river networks, assembly lines of manufacturing systems, and in networks where the customer service locations are all located off a main highway. Solution techniques for TVRPs that explicitly consider their tree structure are discussed in this dissertation. For example, TVRPs do not contain any sub-tours, thereby making it possible to develop faster solution methods. The variants that are studied in this dissertation include TVRPs with Backhauls, TVRPs with Heterogeneous Fleets, TVRPs with Duration Constraints, and TVRPs with Time Windows. Various properties and observations that hold true at optimality for these problems are discussed. Integer programming formulations and solution techniques are proposed. Additionally, heuristic methods and conditions for lower bounds are also detailed. Based on the proposed methodology, extensive computational analysis are conducted on networks of different sizes and demand distributions. / text

A continuous, decadal-scale resolution multi-proxy record of climate variability over the past 1400 years in the northern Gulf of Mexico (GOM) was constructed from a box core recovered in the Pigmy Basin. Proxies include paired analyses of Mg/Ca and oxygen isotopes in the white variety of the planktic foraminifer Globigerinoides ruber and relative abundance variations of G. sacculifer in the foraminifer assemblages. Two multi-decadal intervals of sustained high Mg/Ca values indicate GOM sea-surface temperatures (SSTs) were as warm or warmer than near-modern conditions between 1000 and 1400 yrs BP. Foraminiferal Mg/Ca values during the coolest interval of the Little Ice Age (ca. 250 yrs BP) indicate that SST was 2 - 2.5 degrees Celcius below modern SST. Four minima in the Mg/Ca record between 900 and 250 yrs BP correspond with the Maunder, Spörer, Wolf and Oort sunspot minima, suggesting a link between solar insolation and SST variability in the GOM. An abrupt shift recorded in both the oxygen isotopic ratio of calcite and relative abundance of G. sacculifer occurs ~600 yrs BP. The shift in the Pigmy Basin record corresponds with a shift in the sea-salt-sodium (ssNa) record from the GISP2 ice core, linking changes in high-latitude atmospheric circulation with the subtropical Atlantic Ocean.

Recent improvements in warm mix asphalt technologies have spurred an aggressive adoption of these new practices within the asphalt paving industry. Concerns have arisen among federal and state agencies about the effects of this line of products on the performance of asphalt pavements. An investigation of the effects of lowering mixing, aging and compactions temperatures while varying the loose mix aging time was performed. Hamburg Wheel Tracking, Flow Number, Dynamic Modulus and Fracture Energy testing were used to evaluate mechanistic properties of the materials.

There is increasing evidence that homeothermy (the maintenance of a high and stable body temperature-Tb) as observed in modern mammals was derived from an ancestral heterothermic (flexible Tb regulation) state. One of main hypotheses for why this occurred is that homeothermy benefits parental care. As such the study of the thermoregulatory physiology during reproduction in an otherwise heterothermic mammal can provide insights into the evolution of homeothermic endothermy in mammals. This thesis presents data collected over three reproductive seasons from one such mammal, the greater hedgehog tenrec (Setifer setosus, Tenrecidae). Flow-through respirometry was used to measure resting metabolism over a range of ambient temperatures (Ta). At low Ta S. setosus demonstrated a high propensity for torpor and highly labile Tb. This high degree of heterothermy was abandoned during reproduction; pregnant and lactating females maintained higher Tb and metabolic rates. Tb obtained from free-ranging animals showed similar trends. Reproductive females had less variability in Tb, whereas non-reproductive females and males had a higher propensity for torpor as well as higher overall Tb lability. These data indicate a larger degree of homeothermy during reproduction. Concurrent with the collection of physiological data, the use of radio-transmitters, implanted into the peritoneal cavity along with the temperature data-loggers, allowed for novel observations on the life-history of this little-studied species. The most striking finding was that S. setosus demonstrates an exceptional capacity to assimilate energy. In the short active season males showed high levels of activity and occupied home ranges larger than predicted for their body size. Females, in addition to maintaining a higher degree of homeothermy, can have up to three litters per year. Over this same time period individuals of both sex double their body mass in preparation for hibernation. Such high energetic outputs are thought to be incompatible with the low basal metabolic rates which this species displays. An explanation of this incongruity can be found in the high Ta at the study site, which negated most thermoregulatory costs. In reproductive females, the fitness benefits of small increments in homeothermy seem to be offset by the relatively low fitness costs involved in minimal thermoregulatory energy demands. Homeothermy during reproduction is therefore likely to have been a first step in the progressive evolution from heterothermic to homeothermic endothermy in mammals. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2014.

The cognitive models that research on conceptual change has generated have been the subject of criticism, suggesting that these reflect an unrealistic view of learning as an overly “cold” and isolated process. Accordingly, representatives of this criticism suggest that research on conceptual change should investigate to what extent the cold cognition relates to “warm” affective constructs. In the present thesis, the warmth is not considered as prior to conceptual change, but is inferred from the very process of conceptual change itself. The aim is to investigate and describe how this warmth – in terms of normativity – is expressed in conceptual change and how individuals, in these processes, emerge as subjects in their interchange with the environment. This is done by exploring what students do when they make meaning of gender and nation in interviews and exam papers. The results show that the students mainly relate to two different norm-systems, including six normative aspects of conceptual change. The first system includes the goal to challenge or emancipate, the means to problematize, and engagement in the interviews or exams. Furthermore, it includes critical theory as an ideal, social structures and power as values, and me as a social being and actions as part of a tradition as what to make meaning of. The second system includes the goal to preserve, the means to claim how it “is”, and engagement in the interviews or exams. Furthermore, it includes psychological/biological reductionism as an ideal, essences and a natural order as values, and me as an individual and actions as an outcome of intentions as what to make meaning of. By understanding what the students do as interfering with these normative aspects, it becomes possible to understand them as negotiating norms that are brought to the fore. With this, “coldness” appears to be a misleading epithet of conceptual change. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Submitted. Paper 2: Accepted. Paper 3: Submitted.</p>

A 147cm sediment core from Lake DV09, northern Devon Island, Nunavut, Canada (75° 34’34”N, 89° 18’55”W) contains annually-laminated (varved) sediments, providing a 1600-year record of climate variability. A minerogenic lamina deposited during the annual thaw period and a thin deposit of organic matter deposited during the summer and through the winter, together form a clastic-organic couplet each year. The thinnest varves occur from AD800-1050, and the thickest from AD1100-1300, during the Medieval Warm Period. The relative sediment density is also highest during this period suggesting increased sediment transport energy. The coldest period of the Little Ice Age appears to be during the AD1600s. Varve widths over the past century indicate climate warming in the region. / This research program was funded by the Natural Sciences and Engineering Research Council of Canada (NSERC), and the Canadian Foundation for Climate and Atmospheric Sciences (CFCAS). A tuition bursary from Ultramar Inc. also helped in making this research possible. Logistical support was provided by the Polar Continental Shelf Project (PCSP Contribution number 04508).