Modeling, Simulation and Design of a Laser-type Pressure Sensor

Abstract

In the field of photoelectric sensing and measurement, laser triangulation is a superior and widely used technology due to its advantages of high accuracy, rapidity, and non-contact. This paper first applied it to the measurement of pressure, and proposed and designed a laser-type pressure sensor. The sensor measured the center deflection of the circular pressure-sensitive diaphragm using the laser triangulation, then determined the pressure on the diaphragm according to the small-deflection theory. In the aspect of optical system, the sensor used the principle of lens imaging of magnification and constant focus combining with high-resolution photodetector, which further improved the system accuracy effectively. First the paper created the mathematical model of the laser triangulation in view of the high accuracy, small size requirements. Afterward determined the parameters of the diaphragm in light of the linear range and measurement accuracy of the pressure, and did the finite element analysis of the diaphragm using ANSYS. The analysis demonstrates that within the pressure range, meeting the small-deflection theory, the relationship between the pressure and the deflection is nearly linear. The minimum pressure of the sensors designed is 50Pa, the pressure range is 1.4614MPa, and the maximum relative nonlinearity error of the diaphragm is 1.273%. This simulation design provides a forceful and important basis for the realization of the sensor

From Academic Discourse to Political Decisions? The Case of the Xinjiang Ethnic Unity Education Textbook Reform

“…They argued that sanjiao works towards preventing the Chinese nation-state from being torn apart along ethnic lines and is essential for national "development and prosperity" because it strengthens national cohesion and belonging. 79 The reform clique also uses the sanjiao policy to manifest the central CCP leadership's changing attitude towards ethnic policy in favour of a stronger national identity, a tack followed by Zhu Weiqun 朱维群, another outspoken supporter of the reform clique. 80 Therefore, by using national security as a selling point and tying its research closely to Zhou Yongkang's signature discourse, the reform clique managed to form a solid ideological connection with the CLSG, a move which laid the foundation for more personnel connections later on.…”

Live Migration for Virtual Machine Based on Kalman Prediction of Dirty Pages

“…On the other hand, there may be a larger downtime required to send copies of dirty pages of memory, and affect the migration of virtual machine performance. For the problem of migration data redundancy is too high of pre-copy algorithm, Jin et al [4,5] analyze different characteristics of memory and propose data compression algorithm to reduce the number of memory sending during migration. But if memory compression algorithm selection is not proper, this method may bring additional overhead for the migration system.…”