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We generalize some properties of surface automorphisms of pseudo-Anosov type.First, we generalize the Penner construction of a pseudo-Anosov homeomorphismand show that a symplectic automorphism which is constructed by our generalizedPenner construction has an invariant Lagrangian branched submanifold and an invariantLagrangian lamination, which are higher-dimensional generalizations of atrain track and a geodesic lamination in the surface case. Moreover, if a pair consistingof a symplectic automorphism and a Lagrangian branched surface B satisfiessome assumptions, we prove that there is an invariant Lagrangian lamination Lwhich is a higher-dimensional generalization of a geodesic lamination.

Thermoplastic foams nowadays are used in a wide variety of applications in the automotive, construction, and packaging industry because of their wide range of properties such as light weight, insulation properties, softness, excellent strength/weight ratio, material cost, energy absorption performance. However, there are still issues on the mechanical and other properties in use because of the foam structure. Recently, a new type of continuously coextruded multilayered PP film/PP foam composites was developed. The coextruded multilayered film/foam successfully mimicked the multilayer film/foam structure of natural cork with PP, which enhanced the compression properties due to multilayered film/foam structures. However, there is a lack of a clear understanding how to well optimize the structure-properties due to the insufficiency of the knowledge of rheology of materials related to branching degree of PP and molecular weights. In this thesis, therefore, the first part of thesis (Chapter 2) focuses on the understanding of the effect of strain-hardening on the BPPs film/BPPs foam morphology to optimize the multilayer structures. In Chapter 3, the mechanical properties and the dielectric properties of the multilayer BPPs film/BPPs foams (produced from Chapter 2) are characterized in terms of morphology. Mechanical properties of 16 and 32layer BPP2 film/BPP2 foams such as tensile and compression behaviors reveals the effect of the film/foam structure on the mechanical properties and gives a future idea. Dielectric properties of the biaxially oriented BPP2 foam/BPP2 films are affected by the film/foam morphology such as interfacial area. In Chapter 4 and Chapter 5, the research focuses on the morphology and mechanical properties of multilayer PPs film/PPs foam including flame retardant (FR) particles to achieve improving mechanical properties. Thus, in Chapter 4, the viscosity matched multilayer BPP2 film/BPP2 foams were investigated while in Chapter 5 the viscosity mismatched multilayer LPP film/BPP2 foams were examined. Both exhibited improved mechanical properties and the latter was further enhanced.In Chapter 6, the research emphasizes the effect of the film/foam structure of the multilayer LPP film/BPP2 foam with FR particles produced by Chapter 5 on flame retardancy via multilayer coextrusion, UL-94 test, cone-calorimeter test, and SEM/EDS analysis. The LPP film/BPP2 foam with FR particles exhibits better flame retardancy due to the efficient formation of char layer, caused by the alternating film/foam structure.

This study examines infrastructure investment patterns by the Bell Operating Company (BOC) under price cap regulation (PCR) relative to rate-of-return (ROR) regulation. The question this research asks is whether PCR forces the BOC to charge prices below the monopoly level and influence the company's decision in cost-saving technologies in the local exchange market. PCR is credited with giving the BOC incentives to achieve higher efficiency and make greater investment in telecommunications infrastructure. Existing empirical research on the effectiveness of PCR supports the theory that PCR is superior to ROR in stimulating infrastructure investment and provides an incentive for the company to become more efficient. However, the existing empirical studies fail to consider other important factors such as market conditions in the telecommunications industry, market structure, the nature of the investment, and the firm's strategic behavior.For example, due to market conditions in the telecommunications industry, PCR may not hold the firm's prices below the monopoly level and the firm's strategic behavior may influence investment behavior. If PCR rarely intrudes upon the operation of the BOCs' business, they can maintain high price levels for captive users and engage in strategic infrastructure investment to thwart competition.This research proposes to test two hypotheses. One, if the investment in infrastructure such as fiber optic cables entails large nonrecoverable costs, the BOC invests more under nonbinding PCR than under binding ROR regulation. Two, if the investment in infrastructure such as ISDN is risky, less investment in these technologies will occur under nonbinding PCR than under binding ROR regulation. Under PCR, the BOC will differentiate between investments in technologies that are nonrecoverable relative to those that are recoverable but risky.Empirical results of this research support these hypotheses. The regression coefficient of PCR is significant and positive for the nonrecoverable investment such as the deployment of fiber and digital switches. The regression coefficient of PCR is negative but insignificant for risky investment such as investment in ISDN. The reason the regression coefficient of PCR is insignificant for risky investment is possibly because there is a positive correlation between digital switches and ISDN. These findings indicate the possibility of nonbinding price cap constraints.Some may argue that the empirical results of this research are consistent with the predictions of good economic decision making under PCR, which encourages cost saving and efficiency-increasing investments. However, it is possible that the econometric results obtained can be better interpreted in terms of strategic gaming rather than good economic decision making. Such an inference can be made for two reasons. Binding price cap constraints, in theory, should correct the overcapitalization caused by ROR regulation and provide negative regression coefficients for such investments. Continuous investment in excess capacity cannot be interpreted as cost-saving.This research contributes to our understanding of regulatory regimes in the following way. First, PCR is not always superior to ROR regulation, particularly when there is not appropriate consideration given to market condition and structure. Second, PCR appears to stimulate strategic investment by the incumbent BOCs to deter entry in the local exchange market.