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<p><font face="TimesNewRomanPSMT"> <p align="left">The objective of the present investigation is to calculate observables using the nuclear shell model for a variety of nuclear phenomena and to make comparisons with experimental data as well as the older interaction. The shell-model code OXBASH was employed for the calculations. Quantities investigated include energy level schemes, static magnetic dipole and electric quadrupole moments, electromagnetic transition probabilities, spectroscopic factors and beta decay rates.</p> </font></p>

<p><font face="TimesNewRomanPSMT"> <p align="left">The objective of the present investigation is to calculate observables using the nuclear shell model for a variety of nuclear phenomena and to make comparisons with experimental data as well as the older interaction. The shell-model code OXBASH was employed for the calculations. Quantities investigated include energy level schemes, static magnetic dipole and electric quadrupole moments, electromagnetic transition probabilities, spectroscopic factors and beta decay rates.</p> </font></p>

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With the development and evolution of technology and aviation safety management, the aviation accident rate of the world has been reducing year by year, and the aviation safety situation appears to be improving. Nevertheless, in the analysis of the causes of aviation accidents of local and foreign civil aircrafts happened in recent years, the proportion of the cause being human factors of pilot is as high as 90%. And the two major accidents happened to the Navy in the past 10 years were also related to the human error of pilot. In other words, human factors are is the greatest threats to aviation safety, and should be taken as the core work of aviation safety management in aviation field. The study refers to the literature about the related human factors of the local and foreign civil aircraft and naval aircraft accidents, and takes the SHELL model as the classification criterion of the course structure. As a result, the study has screened and summarized 7 constructs, including ¡§brief introduction of human factors of aviation accidents,¡¨ ¡§aviation physiology of pilot,¡¨ ¡§aviation psychology of pilot,¡¨ ¡§interaction between pilot and other people,¡¨ ¡§relationship between pilot and equipment,¡¨ ¡§relationship between pilot and software,¡¨ and ¡§relationship betweel pilot and environment.¡¨ Under these 7 constructs, the paper designs 60 training subjects. The research approach of the paper adopts two-stage questionnaire survey. In the first stage, aviation experts screened out 7 constructs with 50 more important subjects. After that, survey is made on the helicopter pilots of the Navy and National Airborne Service Corps. Verbal evaluation function is adopted to analyze different constructs as well as the relative weights and sequence of different courses in these constructs. Furthermore, the study develops for the Navy three courses, namely initial training, specialized training and recurrent training, which are applicable to different training targets. Finally, the study refers to the related literature about human factors of civil aviation, and proposes some improvement strategies for the human factors management of naval pilot in order to ensure success of the training of the study. The study sets a 35-hour initial training course, a 26-hour specialized training course, and a 15-hour recurrent training course. Recurrent training course has to be taken regularly every half year. The skill practices of both specialized training and recurrent training can be implemented by the Line Oriented flight training or by the way of role playing so as to let pilots experience their practice in crew resource management. In addition, the study proposes to the Navy some improvement strategies in the aspects of human factors operation doctrine, organization, training and supervision. These improvement strategies and the training courses of the study can be provided to the Navy as a reference for future use in achieving the goal of great improvement on aviation safety.

As a result of the problem of hydrate in multiphase pipelines in offshore production is becoming more and more severe with the increasing of the water depth, the study on oil-gas-water-hydrate has became a hot point of multiphase flow. In this paper, the hydrate particle and liquid phase was treated as pseudo-fluid, the steady hydraulic, thermodynamical and phase equilibrium calculation method of gas-hydrate slurry was developed. Comparison was carried out between calculated data and experimental data from flow loop in our laboratory. With strict flash calculation the following items were determined: the amount of hydrate; phase number; the location that hydrate appeared; flowrate and molar component of gas phase and liquid phase. Then thermodynamic quantities were carried out with proper relational expression. When Compositional model is used to simulate two phase flow, it is required to couple mass, momentum, energy equation and equation of state. In the other word, the parameters in these four equations are interacted. However they are all the functions of p, T and z. In steady condition, it’s assumed that the composition of fluid is unchangeable along the pipeline and the flow can be described by pressure and temperature. In this paper, calculation method of gas-liquid two phase flow which respectively was improved. Liquid holdup and pressure drop were calculated by momentum equation. Enthalpy balance equation was substituted by explicit formulation of temperature calculation which meant that the loop of temperature was not required.

We study the spatial correlations between halo neutrons in 6,8He within the complex-energy Gamow Shell Model (GSM). To this end, we calculate the neutron and proton radii, and two-neutron correlations in a large shell model space consisting of the 0p3/2 resonance and non-resonant p-sd scattering continuum. We use schematic forces and the finite-range Modified Minnesota interaction.The calculated charge radii, corrected for the core polarization and spin-orbit effects, are compared to the values extracted from measured atomic isotope shifts.We find that the charge radius of 6He primarily depends on the two-neutron separation energy and the shell-model occupation of the 0p3/2 orbit.We confirm that the ground-state GSM wave function of 6Heis dominated by the S=0 component representing a di-neutron structure. On the other hand, the correlation density of the 2+ resonance in 6He indicates a very weak di-neutron correlations in this state. We study the effect of pairing correlations on the neutron and charge radii of 6He and we confirm the presence of the Pairing-Anti-Halo effect in this light system.Finally, we calculate the charge radius of 8He in the full GSM space with the help of the Density Matrix Renormalization Group (DMRG) technique. The results of our realistic GSM+DMRG studies presented in this work show promise for extending the reach of the realistic complex-energy shell model to heavier halo systems.

Being a widely used structure, composite shells have been studied for a long time. The features of small thickness, heterogeneity, and anisotropy of composite shells have created many challenges for analyzing them. A number of theories have been developed for modeling composite shells, while they are either not practical for engineering use, or rely on assumptions that do not always hold. Consequently, a better theory is needed, especially for the application on challenging problems such as shells involving thermoelasticity, viscoelasticity, or viscoplasticity.<br><br>In this dissertation, a shell theory based on mechanics of structure genome (MSG), a unified theory for multiscale constitutive modeling, is developed. This theory is capable of handling fully anisotropy and complex heterogeneity, and because the derivation follows principle of minimum information loss (PMIL) and using the variational asymptotic method (VAM), high accuracy can be achieved. Both a linear version and a nonlinear version using Euler method combined with Newton-Raphson method are presented. This MSG-based shell theory is used for analyzing the curing process of composites, deployable structures made with thin-ply high strain composite (TP-HSC), and material nonlinear shell behaviors.<br><br>When using the MSG-based shell theory to simulate the curing process of composites, the formulation is written in an analytical form, with the effect of temperature change and degree of cure (DOC) included. In addition to an equivalent classical shell theory, a higher order model with the correction from initial geometry and transverse shear deformation is presented in the form of the Reissner-Mindlin model. Examples show that MSG-based shell theory can accurately capture the deformation caused by temperature change and cure shrinkage, while errors exist when recovering three-dimensional (3D) strain field. Besides, the influence of varying transverse shear stiffness needs to be further studied.<br><br>In order to analyze TP-HSC deployable structures, linear viscoelasticity behavior of composite shells is modeled. Then, column bending test (CBT), an experiment for testing the bending stiffness of thin panels under large bending deformation, is simulated with both quasi-elastic (QE) and direct integration (DI) implementation of viscoelastic shell properties. Comparisons of the test and analysis results show that the model is capable of predicting most of the measured trends. Residual curvature measured in the tests, but not predicted by the present model, suggests that viscoplasticity should be considered. A demonstrative study also shows the potential of material model calibration using the virtual CBT developed in this work. A deployable boom structure is also analyzed. The complete process of flattening, coiling, stowage, deployment and recovery is simulated with the viscoelastic shell model. Results show that major residual deformation happens in the hoop direction.<br><br>A nonlinear version of the MSG-based general purpose constitutive modeling code SwiftComp is developed. The nonlinear solving algorithm based on the combined Euler-Newton method is implemented into SwiftComp. For the convenience of implementing a nonlinear material model, the capability of using user material is also added. A viscoelastic material model and a continuum damage model is tested and shows excellent match when compared with Abaqus results with solid elements and UMAT. Further validation of the nonlinear SwiftComp is done with a nonlinear viscoelastic-viscoplastic model. The high computational cost is emphasized with a preliminary study with surrogate model.

As part of an ongoing program to study fundamental symmetries in nuclear physics, a thorough investigation into shell-model isospin-symmetry-breaking (ISB) calculation theory has been conducted using direct reactions to observe detailed nuclear-structure information. The work presented in this Thesis focuses on the 62Ga superallowed beta-decay system, and consists of two primary experiments; 1) A 64Zn(d,t)63Zn single-neutron transfer reaction, aimed at observing spectroscopic strengths to help guide calculation model-space truncations for the beta-decay wave function radial-overlap component of ISB, and 2) A two-neutron 64Zn(p,t)62Zn transfer to search for excited 0+ states in the daughter nucleus of 62Ga. The experiments were performed at the Maier-Leibnitz-Laboratory, on the joint campuses of the Ludwig-Maximilians Universitat and the Technische Universitat Munchen, in Garching, Germany. In total, 162 states in 63Zn were populated from the 64Zn(d,t) reaction, up to an excitation energy of 4.8 MeV, including the observation of 125 new levels, and unique spin/parity assignments for 92 states. As a result, this work provides the most complete picture for low-spin states in 63Zn to date. A comparison of the extracted S values to the predicted shell-model spectroscopic factors shows an overall over-prediction of strength for the 2p3/2 orbital, and a large disagreement for the 1f7/2 orbital above ~3.5 MeV. No significant 1g9/2 strength was observed, leading to the conclusion that the importance of the 1g9/2 orbital for ISB is small. Additionally, 67 states were observed in 62Zn using the two-neutron pickup mechanism, including the observation of five 0+ states. More than 99% of the total 0+ (p,t) cross-section is observed in the ground-state reaction channel, implying a nearly maximal overlap of the wave functions with the two-nucleon transfer operator. The dominance of the ground-state-to-ground-state (p,t) cross section is strikingly similar to the dominance of the superallowed Fermi beta-decay between isobaric-analogue 0+ states. This suggests that the population of excited 0+ states in the (p,t) reaction may reflect the population in the Fermi decay process, and can be used to guide future experimental and theoretical work. Further discussion of these results as they relate to the ISB correction calculations, and the implications for future theoretical work are presented in this Thesis. / This work was supported in part by the Natural Sciences and Engineering Research Council of Canada, the Ontario Ministry of Economic Development and Innovation, the DFG Cluster of Excellence `Origin and Structure of the Universe', and NSF grant PHY-1068217.