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The segment assembly machine is a very important part of the shield machine, which is to lining the excavated surface. The segment assembly machine must meet the following two conditions: the segment assembly machine must be lined a full circle of segments accurately and have six degrees of freedom to operate. And the piece assembly must reach high precision, requiring high assembly precision of each component, high rigidity and no creeping when running at low speed. In this research, the force model of the walking beam and roller set of the segment assembly device of shield machine are calculated and analyzed in detail by computer modeling technology and computer simulation technology. The three-dimensional computer-optimized model of the mechanical structure is obtained by a numerical method of the general continuous field problem and the approximate solution of the finite element method. The stress field distribution is obtained, while the stress field distribution map of the roller axle is obtained by the finite element force analysis software combined with the limit conditions in the actual working conditions. It also provides a more advanced design for optimized design of the mechanical structure of the walking beam and roller set and provides a reliable design method for the mechanical module of the segment assembly machine with that theoretical basis of strength design, stiffness design and stability design.

The segment assembly machine, an important part of the shield machine, must be ensured for the timely lining of the excavated tunnel to secure the normal operation and to continue to travel and excavate of the shield machine. The quality of the tunnel assembly will directly affect the penetration and surface settlement of the groundwater, and the speed of the assembly will directly determine that of the shield machine. Therefore, the high quality, speed, accuracy of assembly is the key to the development of shield machine technology. The segment assembly machine is used to lining the surface of the tunnel to ensure the excavated tunnel surface to be consolidated and to be excavated forward. This paper analyzes the function in detail firstly to check out working principle and overall composition of segment assembly translation system of the shield machine. A detail layout and structural optimization design analysis were carried out combined with the partial design and hydraulic control system. Through the coordination study of the mechanical mechanism and the hydraulic control system, the overall performance of the segment assembly translation system is comprehensively reviewed and the segment assembly translation system can be further developed.

The segment assembly system of shield machine is a multi-degree-of-freedom system by hybrid control using electricity and hydraulics. Its control method has great influence on the stability of the whole machine, the stability of the surface and the work efficiency of its system. In order to reduce surface settlement, the assembly machine must be efficient, stable and reliable in its work. The assembly system has six degrees of freedom, and control system of degree of freedom relies on a hydraulic system. Whether it is a translational circuit, a circumferential circuit, a radial circuit, a fine-tuning circuit, a locking circuit and so forth, each circuit achieves a corresponding function by controlling an actuator in the hydraulic system. The system is a hydraulic working system, which uses PLC to control hydraulic cylinders to realize the handling of material segments. The multi-degree of freedom system can realize various movement postures of the segments and position and lock the segments. This paper analyzed the mechanism of its multi-degree-of-freedom series-parallel system. The influencing factors of the weak link of the parallel multi-degree-of-freedom system are analyzed and modified. The research of the fine-tuning system was also carried out, and the control precision and stability of the system were improved through analyzing the influencing factors and optimizing the design of the fine-tuning system. It provides reasonable optimization methods and solutions for the hydraulic system design of various shield machines through the transformation and redesign of the hydraulic system.

The shield machine is a large-scale construction machine with intelligent and highly complex system to achieve the goal of excavation by a hybrid control system of machine with electricity and liquid. Due to the complex and varied working conditions of the excavation, it is necessary to consider the specific excavation parameters and use a variety of tool combinations in order to improve efficiency. Under this condition, this paper comprehensively considers the effects of various condition parameters on the tool. The working mechanism of the shield machine tool is studied by the computer technology. The influence of the environmental change of the working condition on the working mechanism of the tool is discussed in depth. The influence factors of service life of various materials are analyzed, which provides a theoretical basis for the selection of cutters. It provides a comprehensive evaluation mathematical model for the rational construction and application of the cutters, and an important theoretical basis on the development and construction of the intelligent engineering machinery

Polysilicon chemical mechanical planarization (CMP) is an area of research, which has largely been ignored until recently. With the development of bipolar complementary metal oxide semiconductor (BiCMOS), polysilicon has become of increasing importance as the preferred material for filling of deep trench. In this paper, study of removal rates of Polysilicon CMP will be discussed. Traditional models for predicting the polishing rate are typically based on Preston's equation. Here we present a new empirical polishing rate (EPR) model, which is statistically evaluated by cross-validation method, which assess the predictive ability of the model. The study also reveals inadequacies of Preston's equation in describing the polysilicon removal rate in the CMP process.

Cooperative effect radiation loss of optical pump solid laser was investigated deeply. Using Maxwell-Bloch equation the characteristic and cause of coherent spontaneous were discussed .By laser rate equation, the expression of upper energy level lifetime shortening due to the cooperative effect radiation was given. The influence of cooperative effect for laser threshold and the loss were analyzed. Through the experiment, the relation of coherent spontaneous radiation intensity and direction with reversal population and the power of optical pump was obtained.

Two epithelial tumor cell lines were established from biopsy specimens of 2 nasopharyngeal carcinomas (NPC) and designated HNE-1 and HONE-1. Uncloned HNE-1 cells were found to be Epstein-Barr virus (EBV) DNA-positive when examined by Southern blot analysis up to passage 35, after which the EBV genome could no longer be detected. A similar loss of EBV DNA took place in uncloned HONE-1 cells. However, HONE-1 clone 40 cells are still EBV DNA-positive up to passage 42 thus far and cell cultures contain 85-90% EBV nuclear antigen (EBNA)-positive cells. The HNE-1 cell line has been passaged more than 100 times and the uncloned HONE-1 cells more than 90 times. The tumorigenicity of the HNE-1 and HONE-1 cells was demonstrated by tumor induction in nude mice. Karyotypic analysis of the HNE-1 cells demonstrated an aneuploidy with a modal chromosomal number of 74 at passages 5 and 101 at passage 20; 18 marker chromosomes were identified. We have continued to map the EBV genome latently associated with the HNE-1 and HONE-1 cells using the Bam HI, EcoRI or Hind III restriction enzymes. Using EcoRI fragments A-K as probes, we found that HNE-1 EBV DNA is different from B95-8 and HR-1 EBV DNA in the EcoRI-C region. The Bam HI map for HONE-1 EBV DNA is very similar to the B95-8 map; it contains the Bam HI-Y fragment but without Bam HI B' and WI'. Differences were observed between HONE-1 EBV DNA and B95-8 DNA using the Hind III restriction enzyme. There was no evidence of spontaneous expression of the latent EBV genome in HNE-1 cells, and attempts to induce replication of the latent EBV genome and rescue infectious virus have failed, suggesting a tightly restricted virus genome.

Two epithelial tumor cell lines were established from biopsy specimens of nasopharyngeal carcinomas (NPC). The specimens were taken from poorly differentiated squamous cell carcinomas of the nasopharynx. The tissues were prepared for cell culture and eventually two continuous epithelial cell lines were obtained and designated HONE-1 and HNE-1. Light and electron microscopic examination of these two cell lines demonstrated cells with an epithelial morphology including the presence of desmosomes. The HNE-1 cell line has been passaged more than 100 times and the HONE-1 cell line has been passaged more than 90 times. It was found that early-passage uncloned HNE-1 cells (passage 23) could be superinfected with the B95-8 and NPC-EBV isolates as demonstrated by the induction of Epstein-Barr virus (EBV)-specific early antigen(s) in a small percentage of the cells; HONE-1 cells could also be superinfected with EBV. Southern blot analysis detected EBV DNA in samples from uncloned HNE-1 cells at passages 12, 17, 21, 27, and 35. However, by passage 45, EBV DNA could no longer be detected in HNE-1 cells by Southern blot analysis. The EBV genome was detected in parental HONE-1 cells at subculture 9 and in clone 40 cells up to passage 40 thus far. When HNE-1 cells were examined for the expression of the EBV-encoded nuclear antigen (EBNA) at passage 12, only about 10% of the cells were found to be positive. The percentage of EBNA-positive HNE-1 cells decreased as the cells were passaged. A similar loss of EBNA was observed in uncloned HONE-1 cells, but not in HONE-1 clone 40 cells. In clone 40, which has been passaged 40 times thus far, 85-90% of the cells are still EBNA-positive. The data suggest that EBV genome-positive HNE-1 and HONE-1 cells were lost as the cells were cultivated in vitro and that cloning the cells at an early passage level may be critical in maintaining EBV genome-positive epithelial NPC cells. These EBV genome-positive epithelial NPC cell lines will be useful for studying the association of EBV and NPC.