A Theoretical Inquiry into the Problematic Nature of Canadian Defence Policy

This thesis attempts to analyze the problematic nature of Canada’s defence policy by utilizing general systems theory as the prime method of inquiry. While much of the existing literature on Canadian defence policy is of a singular or partial nature, there is a need for a more holistic approach to the study of defence policy. General systems theory, being a normative theory with a scientific base, assumes a holistic approach while offering explanations in behavioural phenomena as well as indicating possible future conditions. This thesis examines the past and present of Canadian defence policy as seen in the perspective of ever-changign political, strategic and military conditions prevailing in the international systems environment. In a developmental sense, this analysis should be regarded as an ongoing process whereby a general theory has been utilized to explain and interpret existing data in such a way as to arrive at a new synthesis in the search for human knowledge

Fiber Optic Coil - Fabrication and Characterization

The goal is to develop a device which periodically couples a pump signal to a signal propagating within a fiber such that the highest amount of optical gain is observed. This idea is based off the proposition that using some form of pump signal will positively contribute to the signal strength within the core of an active fiber configured in a circular coiled arrangement. Initial testing will include measuring the decibel losses of fiber coils as a function of the number of turns, and then using this gathered data to determine the optimal range of wavelengths, for propagation to accept pumping. However, we are still in the process of determining what fiber materials and geometries are most appropriate to use for the above described application. If the idea of a fiber embedded cylinder proves to be sufficient model for boosting the signal within the fiber core, its application lies in a variety of fields and devices within electrical engineering, potentially as a resonator, but more likely as an amplifier utilizing a separate pump source to provide external power to an active fiber optic line. Given the result of the successful development of such embedded cylinders, further studies will likely include systems of such devices and an examination into which other fields these cylinders and corresponding systems can be applied

MEMS 411: The Hash Setting Slasher

The volleyball setter has certain patents that utilize some sort of rotational component or is a stationary platform that the ball rests on before the player hits it. Our design is different because it utilizes the mechanical properties of springs to propel the ball forwards. We had certain specifications to meet to allow the volleyball to be natural in its trajectory and able to be shot efficiently and effectively. Some specifications required positioning adjustments and some defined how the ball should be propelled through the air. We also had parameters involving cost, weight, and the repeatability of the mechanism to hit a desired target. We started with a prototype that represented the general concepts that we wanted to instill in our project and critique ones that wouldn’t be possible. We evaluated what was desirable to have in the full scale volleyball setter and ranked our groups ideas based on certain criteria such as safety, consistency, and transportation. We then used AutoCAD to design a model of how we were going to bring this idea into fruition. Starting the construction of our project, we computed optimal positioning of the mechanism that the shooter will rest on to meet angle specifications. We also computed the distance it will travel based on the spring constants and found springs that would meet predetermined distances. Our safety factor was another important characteristic involved in constructing something that has a large amount of potential energy involved in operating it. We minimized the risk of injury and our safety factor was relatively high. Our final product meets all specifications that apply and comes with a pretty cool decal as well

Phytoplankton growth in nutrient rich seawater: Importance of copper-manganese cellular interactions

Matrix experiments were conducted to determine the role of trace metals in limiting phytoplankton growth rate in seawater collected from the deep nitrate maximum (800 m, 25 µM nitrate) off the North Carolina coast. Additions of FeCI3, MnCI2, and chelators (EDTA and NTA) stimulated the growth of unialgal cultures of Chaetoceros socialis or of a natural phytoplankton community inoculated into this seawater...

Fiber Optic Coil - Fabrication and Characterization

The goal is to develop a device which periodically couples a pump signal to a signal propagating within a fiber such that the highest amount of optical gain is observed. This idea is based off the proposition that using some form of pump signal will positively contribute to the signal strength within the core of an active fiber configured in a circular coiled arrangement. Initial testing will include measuring the decibel losses of fiber coils as a function of the number of turns, and then using this gathered data to determine the optimal range of wavelengths, for propagation to accept pumping. However, we are still in the process of determining what fiber materials and geometries are most appropriate to use for the above described application. If the idea of a fiber embedded cylinder proves to be sufficient model for boosting the signal within the fiber core, its application lies in a variety of fields and devices within electrical engineering, potentially as a resonator, but more likely as an amplifier utilizing a separate pump source to provide external power to an active fiber optic line. Given the result of the successful development of such embedded cylinders, further studies will likely include systems of such devices and an examination into which other fields these cylinders and corresponding systems can be applied

Relationships between population density feeding and growth of the roach (Ratilus ratilus, L. 1758) and other coarse fish in a gravel-pit lake in Southern England

Gravel-pit lakes are an increasingly common feature of our landscape, particularly on the flood plains of rivers close to large urban or industrial areas e. g. the Thames Valley (see Fig. 1). When sand and gravel are removed from below the water table, lakes are produced by seepage into the excavation (wet diggings). At least 1600 hectares of land are being excavated in Britain each year for sand and gravel extraction of which ninety per cent are wet diggings (Hartwright, 1974). Filling with town or industrial refuse (back filling) is not common in wet diggings and the majority of the 1400 hectares dug each year remain as lakes. These lakes provide areas for organised recreation such as sailing, water-skiing, angling and skin-diving. As, open sites, frequently near suburban districts, the lakes and surrounding land can be pleasant amenity areas. Their value is increased if they are landscaped and planted with trees and shrubs (see page 26). Such areas are important for the conservation of a wide range of plants and animals, especially in view of the decline of naturally occurring wetland habitats. Little is known of the biology of gravel-pit lakes; of their flora and fauna or of how these may change with time. Karim (1967) published a paper on the algae of Thames Valley gravel pits and concluded that the air carried the spores of many of the species of algae that colonised the lakes. Catchpole and Tydeman (1975) studied aspects of the bird faunas of several gravel-pit lakes and Harrison (1972) developed a complex of lakes in Kent as a bird reserve. All stress the value of the lakes as habitats for birds. At the City of London Polytechnic a group is investigating the biology of gravel-pit lakes with particular reference to their fish faunas with the aim of establishing principles for managing the lakes as fisheries

Approaching the mind of the builder: analysis of the physical, structural and social constraints on the construction of the broch towers of Iron Age Scotland

Following a review of the paradigmatic context of broch towers in 2012, a revised standard model (the RSM) was defined. The then prevailing paradigm supports a view of broch remains as single monuments of highly variable form that continued in use over perhaps a millennium or more, without significant modification of their original tectonics i.e. their people/constructed-space relationships. This thesis challenges the pre-2012 paradigm by testing the hypothesis that brochs were built to the standard canonical form of the RSM and that their apparent diversity results from anthropic and, or natural modification, not design variability. The fieldwork tests could but did not find refutation of these hypotheses in the observable evidence and offered more profound interpretations of several surviving feature-types. The loading on the stone lintels of the entrance passage through the massively built outer wall and the structurally overladen inner wall created a major structural challenge, evoking a complex engineering solution. Its elements were individually noted pre-2012 but the significance of the engineering response to compression management had not been identified. This structural response was necessary for a tall structure with massive loads, and meaningless without one and its elements are therefore, jointly and severally, clear diagnostics of a broch tower. The entrance engineering was probably the inspiration of one individual or of a small group of master mason-types, not vernacular responses, contra the 2012 paradigm. Isolated stacked voids high in the inner wall are relict features indicative of significant modification of the inner wall. Other anomalous features are shown to be relict stacked void fragments. The East/West differences in brochs across Scotland have long been identified and these are generally attributed to their lithologies. Accepting that, this thesis argues that the principal differences are attributable to the social processes that gave rise to centralisation of settlement around, in and over brochs in the east and north, possibly during the first century BC, and the absence of centralisation in the west; perhaps also explaining the differences in the scale and composition of the artefact assemblages between the two zones. The canonical form facilitates calculation of the relative social costs of broch building for hard-rock and sedimentary stone types. This indicates that the costs of building, increase between 16-, and 32- fold over the buildable range of brochs. Constraints of design down-scalability, design weakness in ground loading, and design cost were major constraints on the mind of the broch builders. Canonicity and the limitations of drystone building technologies predicated specific forms of decomposition on the canonical broch, further complicating their autobiographies and their conservation: the main challenge now being that of finding ways to conserve the evidence for a sequence of processes while conserving the products of those processes

How Do Tiger Moths Jam Bat Sonar?

The tiger moth Bertholdia trigona is the only animal in nature known to defend itself by jamming the sonar of its predators – bats. In this study we analyzed the three-dimensional flight paths and echolocation behavior of big brown bats (Eptesicus fuscus) attacking B. trigona in a flight room over seven consecutive nights to determine the acoustic mechanism of the sonar-jamming defense. Three mechanisms have been proposed: (1) the phantom echo hypothesis, which states that bats misinterpret moth clicks as echoes; (2) the ranging interference hypothesis, which states that moth clicks degrade the bats\u27 precision in determining target distance; and (3) the masking hypothesis, which states that moth clicks mask the moth echoes entirely, making the moth temporarily invisible. On nights one and two of the experiment, the bats appeared startled by the clicks; however, on nights three through seven, the bats frequently missed their prey by a distance predicted by the ranging interference hypothesis (∼15–20 cm). Three-dimensional simulations show that bats did not avoid phantom targets, and the bats\u27 ability to track clicking prey contradicts the predictions of the masking hypothesis. The moth clicks also forced the bats to reverse their stereotyped pattern of echolocation emissions during attack, even while bats continued pursuit of the moths. This likely further hinders the bats\u27 ability to track prey. These results have implications for the evolution of sonar jamming in tiger moths, and we suggest evolutionary pathways by which sonar jamming may have evolved from other tiger moth defense mechanisms

Ranking the Risks from Multiple Hazards in a Small Community

Natural hazards, human-induced accidents, and malicious acts have caused great losses and disruptions to society. After September 11, 2001, critical infrastructure protection has become a national focus in the United States and is likely to remain one for the foreseeable future. Damage to our infrastructures and assets could be mitigated through pre-disaster planning and actions. We have developed a systematic methodology to assess and rank the risks from these multiple hazards in a community of 20,000 people. It is an interdisciplinary study that includes probabilistic risk assessment, decision analysis, and expert judgment. Scenarios are constructed to show how the initiating events evolve into undesirable consequences. A value tree, based on multi-attribute utility theory, is used to capture the decision maker’s preferences about the impacts on the infrastructures and other assets. The risks from random failures are ranked according to their Expected Performance Index, which is the product of frequency, probability, and consequence of a scenario. Risks from malicious acts are ranked according to their Performance Index as the frequency of attack is not available. A deliberative process is used to capture the factors that could not be addressed in the analysis and to scrutinize the results. This methodology provides a framework for the development of a risk-informed decision strategy. Although this study uses the Massachusetts Institute of Technology campus as a test-bed, it is a general methodology that could be used by other similar communities and municipalities