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For understanding the function of a protein, the protein structure plays an important role. The prediction of protein structure from its primary sequence has significant assistance in bioinformatics. Generally, the real protein structures can be reconstructed by some costly techniques, but predicting the protein structures helps us guess the functional expression of a protein in advance. In this thesis, we develop three terms as the materials of the fitness function that can be successfully used in protein backbone structure prediction. In the result of this thesis, it shows that over 80% of good values calculated from our fitness function, which are generated by the genetic programming, are better than the average in the CASP8.

Wave interaction with a rubble-mound breakwater has been studied experimentally in the thesis. The breakwater may contain multi-layer anisotropic but homogeneous media. Fluid outside the porous layer field is assumed to incompressible and viscous,and the flow field is irrational. The study applies the velocity potential to describe the wave field with small amplitude incident wave. Under the consideration of linearity, Analytical solution is solved from boundary value program by the method of separation of variables. It bases on dispersion equation. Try to find the range and position of the complex eigenvalues in each porous column and to solve the velocity potential in the field by numerical methods. Wave reflection, transmission, and energy dissipation with a rubble-mound breakwater have been investigated experimentally, and consider the wave close linear wave theory, the wave steepness smaller than 0.035. Three different sizes of grain are used to construct the porous base, they are 16mm, 25mm, and 35mm, respectively. Single and double layers of porous base are considered. Some of the reflection coefficient are convergence, but they are the unreasonable results. Maybe the trouble is in the process of the computation with determination of .eigenvalues. When the wave has long period, the double-layer porous model reduces more wave energy, when the wave has short period, the single-layer porous and the smaller porous material model can disappears more wave energy. The characteristic of internal resistance in the porous has the difference along with the wave period. When the model crest is higher than the sea level, the consumption of wave energy are more when it is shorter along with the wave period. As a submerged breakwater, the effect for disappears wave energy to be limited.

Many field, experimental, and theoretical studies have contributed greatly to our understanding of the occurrence and formation of deformation bands in porous granular materials, but questions remain regarding the mechanics of strain localization, and how the orientation, thickness and internal strain (shear relative to volume change) of deformation bands is influenced by loading history and evolving rock properties. Here we report on triaxial rock deformation experiments using a non-traditional sample geometry to investigate band formation across the brittle-ductile transition. Five-cm diameter cylinders of Berea sandstone were machined with a circular (8.77 cm radius) notch to form a dog-bone sample geometry. In triaxial compression, the sample geometry obviates end-effects without creating heterogeneous stress gradients that can influence localization. Samples were instrumented to measure local strains in the neck region and acoustic emissions (AE), and then shortened to failure at confining pressures of 50 to 250 MPa. Deformation bands formed at all conditions, and photo mosaics of the outer sample surface were used to determine the thickness and orientation of the bands. Band thickness increases from several to tens of mm thickness and the angle between the bands with the shortening axis changes from 35 to 80 degrees, as confining pressure increases from 50 to 250 MPa, respectively. Mechanical data, including local strain measurements through yield, were used to test theoretical models for the onset of localization and formation of deformation bands as an instability in the constitutive description of homogeneous deformation. Generally, theoretical predictions compare favorably with the observed onset of localization determined by marked changes in the AE rate, and are consistent with the formation of compacting shear bands at higher mean stress. Predictions of changes in band orientation with mean stress are largely consistent with observed trends, but deviate from the observed orientation by as much as twenty degrees.

As a part of a larger effort towards the fundamental understanding of structureproperty relationship in nanoplatelet-reinforced polymer nanocomposites, a set of model epoxy systems containing α-Zirconium Phosphate (α-ZrP) have been prepared and studied in this dissertation. A new surface modification approach, i.e., the porous pathway approach, for improving intercalation efficiency and exfoliation of layered nanoplatelets has been proposed and the effectiveness has been demonstrated. In order to clearly understand the roles of nanofillers and the effects of their geometric factors on the physical and mechanical properties of nanocomposites, variables such as nanoplatelet loading level, degree of exfoliation, and aspect ratio have been carefully controlled in the epoxy matrices. Morphological information of the prepared nanocomposites was unambiguously confirmed by carrying out X-ray diffraction and transmission electron microscopy (TEM). Tensile and thermo-mechanical properties of the model epoxy/α-ZrP nanocomposites have been investigated. Furthermore, fracture behavior of the model nanocomposites is examined in this study. This work has enhanced the understanding of the effects of nanoplatelet, i.e., loading level, degree of exfoliation, aspect ratio, and the type of surface modifiers, on the mechanical properties and fracture behavior of polymer nanocomposites.

The increase of multi-drug resistant and extensively drug resistant tuberculosis (TB) cases makes it urgent to develop a new generation of TB drugs to counter resistance and shorten treatment. Structural biology, which allows us to “visualize” macromolecules, is now playing a key role in drug discovery. In this work, a structure-based approach was applied to the study of the mode of action of current TB chemotherapies, the identification of potential therapeutic targets, and the design of new inhibitors against TB. Knowledge of the precise mechanisms of action of current TB chemotherapies will provide insights into designing new drugs that can overcome drug-resistant TB cases. Structural biology combined with biochemical and genetic approaches was used to elucidate the mechanisms of actions of isoniazid, ethionamide and prothionamide. The active forms of these anti-TB prodrugs were identified by protein crystallography and the target-inhibitor interactions were revealed by the complex structures. Although these drugs are activated through two completely different routes, they all inhibit InhA, an essential enzyme in mycolic acid biosynthesis, by modification of the enzyme cofactor NAD, which unveils a novel paradigm of drug action. Isoniazid, ethionamide and prothionamide all target InhA, which validates the enzyme as a superb drug target. A structure-based approach was adopted to design new inhibitors targeting InhA, using triclosan as the scaffold. Guided by the InhA-inhibitor complex structures, two groups of triclosan analogs were identified with dramatically increased inhibitory activity against InhA. Structural biology has also provided fundamental knowledge of two potential therapeutic targets, Mtb β-lactamase (BlaC) and fatty-acyl-CoA thioesterase (FcoT). Mtb β-lactamase has been proposed to be the most significant reason for mycobacterial resistance to β-lactam antibiotics. The determination of Mtb BlaC structure not only demonstrates the mechanism of drug resistance but also provides a solid base for the design of new β-lactamase inhibitors that could be used with β-lactam antibiotics as a new regimen to treat tuberculosis. The crystal structure of FcoT provided crucial information in identification of the function of this previously hypothetical protein. The characterization of FcoT revealed an important pathway that is critical for Mtb’s survival in host macrophages.

The large-scale environment can have a significant impact on subtropical precipitating systems via the baroclinicity of the environment and the associated dynamical forcings. The degree of baroclinicity is examined using National Centers for Environmental Prediction (NCEP) reanalysis temperature and zonal wind fields over a two-year period for Southeast Texas, yielding classifications of barotropic, weakly baroclinic, and strongly baroclinic for the background environment. Weakly baroclinic environments accounted for half of the days throughout the two-year period. Barotropic environments occurred most frequently during summer and strongly baroclinic environments occurred most frequently in winter, although less often than weakly baroclinic environments. A climatology of storm types, based on dynamical forcing (i.e., weak forcing, drylines, cold fronts, warm fronts, stationary fronts and upper level disturbances) and precipitation structure (i.e., isolated, scattered, widespread, linear, unorganized and leading-line/trailing stratiform), was compiled and compared to the baroclinicity designations. Non-frontal storm types (i.e., weak forcing, drylines and upper level disturbances) are typical of barotropic environments, while frontal storm types (i.e.,warm, cold and stationary fronts) are typical of weakly and strongly baroclinic environments. Storm events and drop-size distributions (DSD) were identified from surface rainfall data collected by a Joss-Waldvogel disdrometer located in College Station, Texas. The DSDs were compared by baroclinicity and storm type. The barotropic DSD is weighted towards the largest drops because of the stronger convection and stratiform precipitation in the weak forcing and dryline storm types, while the strongly baroclinic DSD is weighted towards the smallest drops because of the weaker convection from the warm fronts and stationary fronts. The weakly baroclinic DSD is weighted more evenly towards small and large drops than the barotropic and strongly baroclinic DSDs because of the conflicting microphysical processes in the different storm types. The microphysical processes within the storms vary by storm type and baroclinicity regime, such that the large-scale environment modifies the precipitation characteristics of storms in SE Texas.

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The future direction of enterprise depends upon the contribution of organizational management. Based on acknowledgement of organization, the efficiency of enterprise comes from the design of an organization model. An organization model is to represent an organization systematically and logically. For an architectural organization model, the significant characteristic lies on the perfect integration between organization structure and organization process. Through the interaction among structure elements, architectural organization model breaking down the bar style management model and linear operation thinking and adopt architectural management, it will fulfill the enterprise superiority and also increase an enterprise¡¦s execution capability. During the rapid expansion, the enterprise faces changes of internal organization management and external environment. When the information increases among different regional departments, it requires more efforts to coordinate and the cost is highly raised. Therefore, we need a new organization model to resolve the business cost of an enterprise. Comparing with the traditional inflexibility organization process, the dynamic efficiency of architectural organization model provides faster reaction to coordinate the resources and adjust the strategies. This thesis is to build up an architectural organization model which shall overcome the fatal flaw of traditional organization models. In the era of knowledge, an enterprise¡¦s key competitive strength relies on knowledge and experience, not on equipments, capital, or technique. The important strategy of organization management is adopting organization experience as the main capital of an enterprise and building up new organization values. Through the compact integration of organization structures and organization processes, architectural organization model provides a mutual-learning platform for all employees within an enterprise and develops intelligent management, thus becomes a main trend for modern enterprises to follow. Facing the arrival of new knowledge era, we will own more creativity though learning by each other. Believing in that we gain more by sharing this study and experience, thereafter we anticipate our study would play a significant role in the organization management research.