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With the continuous increase of urban population, the development degree of urban underground space is increasing, and the pipe jacking method has been widely used in the construction of urban underground space. This paper analyzes the disturbance mechanism of the pipe jacking construction on the surrounding soil, and analyzes the actual results of the surface subsidence in the rectangular pipe jacking project of Baima Road in Fuzhou Baolong Wanxiang Square and the civil defence project. By combining the three-dimensional finite element model, the law of ground surface settlement and deformation during the construction of shallow-buried large-section pipe jacking under the conditions of coastal stratum is studied. And through the on-site monitoring settlement data of the project and the finite element simulation, the ground surface subsidence deformation law and the pipe-tube stress variation law of the shallow-buried large-section pipe jacking under the coastal stratum are mastered, which can be used for the design and construction of related similar projects for reference in the future.

The excavation of connected aisle is one of the key risks for the construction of subway in the coastal soft clay layer. The excavation of sump-pit will adversely affect the deformation of the ground and connected aisle, increase the risk of the project. The finite element software ABAQUS is used to carry out numerical simulation research on the excavation of sump-pit. The influence of deformation of ground and connected aisle were analyzed by the method of changing the position of sump-pit excavation. The result showed that: the most significant influence of sump-pit excavation was crown settlement, the second important influence was ground settlement, and the influence of headroom convergence was slight. The maximum ground settlement increased by 7% and the maximum crown settlement by 13% if the sump-pit was built in the middle of connected aisle.

Electron crystallography has been proven to be effective for structure determination of nano- and micron-sized crystals. In the past few years, 3D electron diffraction (3DED) techniques were used for the structure solution of various types of complex structures such as zeolites, metal-organic frameworks (MOF) and pharmaceutical compounds. However, unlike X-ray crystallography, electron diffraction has not yet become an independent technique for a complete structure determination due to relatively poorer diffraction intensities and often powder X-ray diffraction data are used for structure validation and refinement. Electron beam damage to the structures that are sensitive to high energy electrons and dynamical scattering are important factors to lead to the deviation of electron diffraction intensities from the squared amplitudes of the structure factors. In this thesis, we investigate various aspects around the 3D electron diffraction data quality and strategies for obtaining better data and structure models. We combined 3D electron diffraction methods and powder X-ray diffraction to determine the structure of an open-framework material and discussed the difficulties and limitations of electron diffraction for beam sensitive materials. Next, we illustrated the structure determination of a pharmaceutical compound, bismuth subgallate, using 3D electron diffraction. While severe beam damage and diffuse scattering were observed in the dataset collected with the conventional rotation electron diffraction (RED) method, the continuous rotation electron diffraction (cRED) method coupled with sample cooling significantly improved the data quality and made the structure solution possible. In order to better understand the potentials and limitations of the continuous rotation method, we collected multiple datasets from different crystals of a known structure and studied the data quality by evaluating the accuracy of the refined structure models. To tackle dynamical scattering in electron diffraction data, we explored a routine for structure refinement with dynamical intensity calculation using RED data from a known structure and discussed its potentials and limitations. At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.

Based on a series of realistic background about internal control system, such as "Audit Guidance for Enterprise Internal Control", this paper has taken the listed corporations in information technology industry as research samples and has studied the influence of audit attestation service on the effectiveness of enterprises' internal control. It has found that: the audit attestation service offered by accounting firms helps to improve the effectiveness of internal control, compared with that by other accounting firms, the audit attestation service provided by the national top ten accounting firms contributes more to that improvement. These results have offered some empirical evidence support to the implementation of audit attestation for internal control, and also to the institutional arrangement for promoting the development of accounting firms. A feasible reference path has been presented to enhance the endurance the effectiveness of internal control.

Under the "new normal" of the development in financial services, high-quality of customer service experience is the core product of commercial banks, but also the determinant of new driver for competitive position in commercial bank industry. Based on the perspective of internal marketing, this study has taken 206 front-line employees in commercial banks as research samples and analyzed the impact of commercial banks' internal service quality on service performance. The study suggests that internal service quality has a positive effect on the service performance of front-line employees. Job satisfaction has a mediating effect between internal service quality and service performance, and trust has a moderating effect between internal service quality and service performance. This study has opened a black box (internal service quality a#x2192; service performance), which would provide some theoretical support for the commercial banks to upraise the front-line employees' satisfaction and improve their service performance.