Complex networks is an interdisciplinary research area which focuses on the study of properties of complex systems that have many functional or structural subunits. Community detection algorithms are one of the major approaches to analyse complex networks with multilevel or overlapping community structures. This research work focuses on constructing a novel community detection approach for simplification of a given complex demographic network. The general process of the abstraction from concrete problems as well as the general definition of communities have not been well defined and all the existing methods are derived from specific backgrounds, leaving the reliabilities in other fields open to ques- tion. This specificity of the existing methods reveals the need for a general approach for community definition and detection. Here, we devise a general procedure to find community structures in concrete problems by classifying the concrete networks into two basic types: Transmission networks and Similarity networks. The relation among nodes in transmission networks are constructed by material transmission and the ones in similarity network are constructed by the similarity in properties of the nodes. We show that both the types can be represented based upon an unified graph model. Based on the model, we propose a generic approach, Relation Strength Measurement (RSM), to define the communities. We have demonstrated that the Effective Resistance Function (ERF), from the Klein and Randic’s electrical network model, is applicable for quantifying the relation among nodes. We have also introduced a community threshold parameter (CP) based on which, the RSM algorithm categorizes the network nodes into communities. We have compared the performance of our algorithm with other well known community detection methods. The simulation results show that the algorithm accurately obtains the division of community structure both in real-world and synthetic networks.

The dynamic properties of clay deposits under seismic or wave loading conditions must be well understood to assure dynamic stability of structures founded on such soil. The dynamic shear modulus and damping appear to be a complex function of many variables, and a wide range of values have been reported in the literature. Consequently, considerable uncertainty exists in choosing the appropriate values of shear modulus and damping for a particular problem. This thesis presents a study of the influence of various factors on the shear modulus and damping of a marine clay using a resonant column/torsional shear device. In particular, the influence of factors such as shear strain amplitude, effective confining stress, stress history, frequency (strain rate), and secondary time-dependent behaviour are examined. The pore pressure response is also studied. The shear modulus was found to degrade for shear strains above 0.005%. The strain dependency was found to be well represented by a single normalized modulus reduction curve regardless of the confining pressure or overconsolidation ratio. Slower strain rates resulted in smaller values of shear modulus. Of the variables studied, the duration of sample confinement was found to be the most imporant factor affecting the material damping. Above 0.005% strain, the damping of the marine clay increased with shearing strain amplitude. No significant effect of confining pressure and stress history on damping was observed at any strain level. As well, the material damping was found to be relatively independent of loading frequency. Both the shear wave velocity and damping obtained in this study were found to be consistent with the in situ values determined using the seismic cone penetration test. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate

The purpose of this study was to compare the effects of strength training by eccentric and isometric contractions in relation to isometric right leg strength. A secondary purpose was to determine if individual differences in eccentric strength gains were related to individual differences in isometric strength gains. Forty-five volunteer subjects were systematically assigned to three groups in such a manner that these groups were balanced in terms of initial isometric leg strength. The groups were then randomly assigned to experimental and control conditions. One group trained with eccentric contractions, another with isometric contractions and the last acted as a control. The groups were tested for isometric leg strength before and after a six week training program. The Eccentric Group was also tested for eccentric leg strength during the first and last training sessions. The training sessions took place three times per week and three maximal contractions were performed during each session. The results indicated that both isometric and eccentric training produced significant isometric strength gains (t = 7.13, 6.64 respectively, p < .05) when compared to the Control Group. However, there was no significant difference between the strength gains of the two experimental groups (t = .49, p > .05). Within the eccentrically trained group it was also found that eccentric strength was significantly improved due to training (t = 5.52, p < .05) but that this improvement was uncorrelated (r = .27) with isometric improvement scores. Within the limitations of this study, it was concluded that isometric and eccentric training were of approximately equal value in increasing isometric strength. Further, there was no relationship between isometric improvement scores and eccentric improvement scores. / Education, Faculty of / Curriculum and Pedagogy (EDCP), Department of / Graduate

This thesis describes attempts to measure the shearing strength of freshly mixed concrete and relate it to standard "Workability" tests. The study is a continuation of investigations made by Mr. Li Yang in 1963-65 at the University of British Columbia. Yang measured the shearing strength of eight mixes at one velocity and obtained a type of "viscosity" at that speed. This thesis broadens the investigation to shear strength of eight different mixes at seven different speeds. The shear box developed at the University of British Columbia and used by Mr. Yang was used in these further investigations and the shapes of the shear vs. rate of shearing strain or "viscosity" curves for eight different mixes was partially developed. / Applied Science, Faculty of / Civil Engineering, Department of / Graduate

This thesis presents a finite element (FE) modelling approach investigating the effects of corroded shear reinforcement on the capacity and behaviour of shear critical reinforced concrete (RC) beams. Shear reinforcement was modelled using a “locally smeared” approach, wherein the shear reinforcement is smeared within a series of plane-stress concrete elements at the specific stirrup location. This was done with the objective of incorporating both the reduction in cross-sectional area due to corrosion and the corresponding expansion of corrosion products build up. Corrosion damage was incorporated through equivalent straining induced by the corrosion build up on the affected surrounding concrete where the concrete cover was treated as a thick-wall cylinder subjected to internal pressure. Strains were introduced in the FE model using fictitious smeared horizontal pre-stressing steel, with a compressive pre-straining level related to the degree of corrosion penetration of the reinforcement. The FE modelling approach was first validated against published test data of shear critical RC beams with and without stirrup corrosion. The proposed modelling approach successfully reproduces the load deformation response as well as the failure mode and cracking patterns of the published experimental tests. Upon validation of the FE model, the work was extended to a parametric analysis of important shear design variables, such as the shear span-to-depth ratio, beam width and stirrup spacing The FE analyses were carried out for three increasing levels of corrosion (low, moderate and high) applied to affected stirrups within the critical section of the beams and based on steel mass loss (10%, 30% and 50%, respectively). In general, the results show a reduction in load carrying capacity accompanied by a softening of the load-deformation curves with each increasing level of corrosion. In most of the cases, a reduction in deflection associated to peak loads was also observed for moderate and high levels of corrosion. The impact of the various parameters was studied with respect to strength and deformation, as well as crack angle and mid-height horizontal strain. This was done in an effort to compare FE values to those provided by the CSA A23.3 design equations. The CSA A23.3 shear design equations were compared against FE analysis data in terms of residual shear strength estimation and individual component contributions to shear resistance (i.e., concrete and steel). The comparisons revealed an over conservative estimation for both strength and concrete contributions and an overestimation of the steel contribution. This divergence was attributed to a transition in shear behaviour within the critical section. Based on the progression of the concrete compressive struts with increasing corrosion and predicted crack angle, it was found that stresses in affected sections are redistributed towards adjacent undamaged material. The shear resistance mechanism generally transitioned from typical beam behaviour towards an arching-dominated one. Finally, based on important findings from the literature and the work conducted within this research, important considerations for assessment practice are suggested.

OBJECTIVE: To evaluate if the firing cycles and etching conditions have an effect on the tensile bonding strength (TBS) of IPS e.max-CAD and CeltraDUO. METHODS: Lithium-disilicate (IPS e.max-CAD) ceramic blocks and zirconia reinforced lithium-disilicate (CeltraDUO) were sectioned into rectangular tiles. The tiles were randomly assigned to various treatment groups and heat treated (1, 5, or 9 firing cycles) or (0, 1 or 5 firing cycle) respectively. e.max-CAD and CeltraDUO tiles were etched for different times (20,160, 300 seconds) and (20, 50, 80 seconds) respectively with hydrofluoric-acid gel (9.6% or 5%). Titanium-pins were sand-blasted on the flat end and cemented on the etched tiles using self-adhesive resin cement (TheraCem). A vertical load of 12N was placed for 40 minutes. All the cemented specimens were stored in incubator at 37°C for 48 hours. A tensile test was performed using a mechanical testing machine (Instron-5566A). The load at failure was recorded and the TBS was calculated. The same procedure was followed on another set of 18 e.max-CAD (fired for 5 firing cycles) and 21 CeltraDUO tiles (fired for 1 firing cycle). The same cementation procedure was followed and TBS was calculated. RESULTS: The TBS of both CeltraDUO and e.max-CAD was significantly affected by etching duration and firing cycles (p<0.001), but not significantly affected by etchant concentration (p=0.31). The highest load to failure was observed around 50 and 60 seconds of etching respectively. CONCLUSION: The etching time and firing cycle directly affect the TBS of both materials whereas the etchant concentration does not. / 2021-07-15T00:00:00Z

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Research has shown that lower limb asymmetries can negatively impact performance and risk of injury. However, there is little research on the effects of lower limb asymmetry on running performance, nor the effects of strength training on lower limb asymmetry in runners. The purpose of this study was to examine the relationship between jumping ability and asymmetry and long distance running performance, as well as to determine the performance effects a strength training program has on collegiate runners. Data from athlete monitoring of 10 collegiate distance runners and 6 sprinters were analyzed. Athletes (Distance Runners n = 10, Sprinters n = 6) performed static and countermovement jumps at two testing sessions separated by 21 weeks, during which, they participated in a block-periodized strength training program. The athletes were capable of maintaining a minimal amount of kinetic asymmetry during the jump tests and there were no statistically significant correlations between jump height, jump asymmetry, and cross-country race times. After the strength training intervention, the female distance runners significantly improved static jump height (p value = 0.045), countermovement jump height (p value = 0.015), countermovement jump asymmetry percentage (p value = 0.006), and body fat percentage (p value = 0.002). Although there were no other statistically significant changes, there were promising trends in many of the performance variables. These results indicate that there are potential benefits associated with strength training, and coaches should incorporate it into the overall programming for collegiate runners for injury prevention and enhanced performance.

The purpose of this study was to examine the influence of content of a copovidone binder (0%, 5% and 10% w/w) and its addition method on compression and compaction properties of six MCCformulations following dry granulation. Briquetting was used to form dry granules for furthercharacterization. The mean yield pressure and fracture strength of granules were assessed at 300MPa on the basis of “in-die” Heckel and Adams model respectively. Then tablet tensile strengthof manufactured tablets was determined at 100 and 300 MPa. The results demonstrated thatintragranular addition of further binder (10%) to MCC could increase plasticity. However, therewas a drastic reduction in compactibility of dry granules mostly impacted by binding capacity ofthe binder. Generally, 5% intragranular:5% extragranular binder under a compaction pressure of300 MPa had the greatest binder efficacy on strength of pure MCC tablets while 10%extragranular binder improved tensile strength significantly at 100 MPa. PVP in a level of 5%w/w had no significant impact on tensile strength of tablets compacted at 100 and 300 MPa.

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