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The joint may be considered a weak point along the pipe and can have a major impact on pipe performance. However, little research has been conducted in regard to joint design. To improve current structural design criteria, this thesis presents the findings and conclusions of experimental and computational studies of the effects of longitudinal bending on joints in rigid (reinforced concrete) and flexible (corrugated steel and thermoplastic) pipes. Solutions for expected shear force, longitudinal bending moment and rotation across the joint for rigid and flexible pipes are formulated for use in structural design of pipe joints. Exact algebraic solutions for rigid pipes are derived using the beam-on-elastic-spring approximation. The formulations for flexible pipes are developed assuming that the two pipes are very long, and that the response is not affected by either the location or characteristics of those other joints. The flexible pipe design equations are developed using various closed form solutions for beams on elastic foundations developed by Hetényi (1948). Parametric studies are then presented where the key factors controlling the behaviour are examined, and the comparisons to recent experimental measurements show that the joint rotation calculated using the equations and a value of soil stiffness proposed for use in design are generally reasonable and conservative compared with the laboratory tests. To measure the capacity of the joint to accommodate the demands, a pipe joint testing frame has been designed to facilitate joint characterization experiments. Shear tests and articulation (rotation) tests have been conducted using this testing frame to examine the shear force capacity, longitudinal bending moment capacity of moment-transfer joints, and rotational characteristics of joints. The shear test results show that the joints of PVC pipe and corrugated steel pipe have similar shear stiffness while the reinforced concrete pipe joint is significantly stiffer. The results of the articulation testing indicate that the rotational capacities of the three joint systems are similar in general. Design of rotational capacity of these joints is likely dominated by considerations of assembly in the field, rather than the rotational capacity that is needed once the pipes are installed. / Thesis (Master, Civil Engineering) -- Queen's University, 2013-01-31 15:33:41.058

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This thesis investigates two problems that are discrete analogues of two harmonic analytic problems which lie in the heart of research in the field. More specifically, we consider discrete analogues of the maximal Kakeya operator conjecture and of the recently solved endpoint multilinear Kakeya problem, by effectively shrinking the tubes involved in these problems to lines, thus giving rise to the problems of counting joints and multijoints with multiplicities. In fact, we effectively show that, in R3, what we expect to hold due to the maximal Kakeya operator conjecture, as well as what we know in the continuous case due to the endpoint multilinear Kakeya theorem by Guth, still hold in the discrete case. In particular, let L be a collection of L lines in R3 and J the set of joints formed by L, that is, the set of points each of which lies in at least three non-coplanar lines of L. It is known that |J| = O(L3/2) ( first proved by Guth and Katz). For each joint x ∈ J, let the multiplicity N(x) of x be the number of triples of non-coplanar lines through x. We prove here that X x2J N(x)1=2 = O(L3=2); while we also extend this result to real algebraic curves in R3 of uniformly bounded degree, as well as to curves in R3 parametrized by real univariate polynomials of uniformly bounded degree. The multijoints problem is a variant of the joints problem, involving three finite collections of lines in R3; a multijoint formed by them is a point that lies in (at least) three non-coplanar lines, one from each collection. We finally present some results regarding the joints problem in different field settings and higher dimensions.

The scope of this thesis is to analyze the feasibility of having different wireless mesh network architectures transfer data to a wired network via a joint (universal) access point (UAP). Additionally this thesis analyzes the feasibility of using similar joint (universal) access point technology to allow heterogeneous wireless mesh network devices in close proximally to the UAP transmit data to/from each other via the UAP. This research also includes evaluating COTS tools for possible implementation of a joint access point as well as seeking partnership with private industry to assist in research efforts and/or the development or joint (universal) access point solution(s). The thesis concludes with a recommendation on application of universal joint point technology, to include recommendations for implementation of such technology in the Tactical Network Topology (TNT) environment.

Bone makes up a framework that provides protection for internal body organs. The homeostasis of bone is maintained by a balanced process involving old bone degradation and new bone formation. However, this balance can be altered in pathophysiological conditions such as in postmenopausal osteoporosis and in patients with rheumatoid arthritis (RA). In recent years, new therapies have been developed to reduce bone resorption. However, there is disparity in patients’ response to these therapies. The reasons are unclear although age, gender, ethnic background and lifestyle have all been suggested to play a part. For patients with chronic inflammatory conditions, treatment was revolutionised by the discovery and application of biologic therapies that target pro-inflammatory proteins and/or pathways. However, whilst the anti-inflammatory effect of these biologic agents is well-established, their effect on bone loss is just emerging. In RA, it is not clear whether the beneficial anti-inflammatory effects of biologic anti-tumour necrosis factor alpha (TNFα) agents are accompanied by parallel improvements in bone erosion/density, whether there are differences between patient groups and what factors influence the response. In order to address these issues, a database on the factors that influence responsiveness of patients with osteoporosis to bisphosphonates, a treatment that suppresses bone resorption, was established. Based on the outcome of this study, the influence of the key factor(s) that affect bone response to treatment in combination with excess pro-inflammatory cytokine production on bone response in RA patients was determined. Significant improvement in bone mineral density (BMD) and plasma levels of bone biomarkers has been shown in this study with biologic anti-TNFα agents. The improvement in BMD was not always consistent with improvement the clinical response to treatment as assessed by changes in disease activity score 28(DAS28). The study also provides a mechanistic explanation for how blockade of TNFα in patients can reverse the balance of bone loss in patients with RA. Thus, the data show that treatment of patients with biologic anti-TNFα agents reduces the number of osteoclast precursors (OCs) in the blood.