In this paper,a binocular 3-D computer vision measurement system is used to measure the relative displacement for the greater and lesser tuberosities in the shoulder prosthesis.The basic principles of binocular optica...In this paper,a binocular 3-D computer vision measurement system is used to measure the relative displacement for the greater and lesser tuberosities in the shoulder prosthesis.The basic principles of binocular optical measurement are introduced in detail,and the loading apparatus is designed for external rotation and anteflexion of the shoulder prosthesis.Both the motion of external rotation and anteflexion of the shoulder are measured,and the corresponding displacement values for the greater and lesser tuberosities are extracted.These results will play an important role in evaluating the stability of humeral tuberosity in the shoulder prosthesis.展开更多
Superplastic alloy has very strong structure sensitivity. Superplastic bulging with a die of the plate is related not only to stress state but also closely to loading paths. It is an important basis for bulging formin...Superplastic alloy has very strong structure sensitivity. Superplastic bulging with a die of the plate is related not only to stress state but also closely to loading paths. It is an important basis for bulging forming with a die to study deformation law and experimental apparatus for superplastic free bulging, because the boundary of test piece is fixed and friction is insignificant for free bulging. In the paper, a pure high-pressure argon gas source is used as the loading media after it is heated by the heating system outside the furnace, which improves the heating efficiency and temperature uniformity of the test piece. The photoelectric non-contact measurement device can avoid negative influence on the additional stress and uneven temperature at the peak of bulging part caused by push rod in the contact measurement. The temperature and pressure of the test piece in cylindrical insulation furnace with blank holder give feedback control to improve the control precision. In loading gas channels, the pressure is adjusted by accurately measuring and controlling the rotation angle of the stepping motor, and is loaded by an electro-magnetic valve. It significantly increases the response characteristics of the control pressure. This paper also introduces steps and methods to realize several typical loading paths, such as constant pressure, jump pressure and additional back & differential pressure loading. These provide a new way to measure the strain rate sensitivity index m value and improve the deformation speed of superplastic free bulging.展开更多
The paper studies the ground vertical deformation and the geoid undulation caused by loading of neighboring buildings, based on the loading tides theory. The influence on elevation is also considered. The results show...The paper studies the ground vertical deformation and the geoid undulation caused by loading of neighboring buildings, based on the loading tides theory. The influence on elevation is also considered. The results show that the ground vertical deformation and the geoid undulation both reach millimeter magnitude. Therefore, it is obvious that the building loading significantly affects the precise engineering surveying, and it must be seriously considered in application.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos. 30470430,10802106)
文摘In this paper,a binocular 3-D computer vision measurement system is used to measure the relative displacement for the greater and lesser tuberosities in the shoulder prosthesis.The basic principles of binocular optical measurement are introduced in detail,and the loading apparatus is designed for external rotation and anteflexion of the shoulder prosthesis.Both the motion of external rotation and anteflexion of the shoulder are measured,and the corresponding displacement values for the greater and lesser tuberosities are extracted.These results will play an important role in evaluating the stability of humeral tuberosity in the shoulder prosthesis.
基金supported by the Natural Science Foundation of Jilin Province (Grant No. 201115015)the National Natural Science Foundation of China (Grant No. 51005099)
文摘Superplastic alloy has very strong structure sensitivity. Superplastic bulging with a die of the plate is related not only to stress state but also closely to loading paths. It is an important basis for bulging forming with a die to study deformation law and experimental apparatus for superplastic free bulging, because the boundary of test piece is fixed and friction is insignificant for free bulging. In the paper, a pure high-pressure argon gas source is used as the loading media after it is heated by the heating system outside the furnace, which improves the heating efficiency and temperature uniformity of the test piece. The photoelectric non-contact measurement device can avoid negative influence on the additional stress and uneven temperature at the peak of bulging part caused by push rod in the contact measurement. The temperature and pressure of the test piece in cylindrical insulation furnace with blank holder give feedback control to improve the control precision. In loading gas channels, the pressure is adjusted by accurately measuring and controlling the rotation angle of the stepping motor, and is loaded by an electro-magnetic valve. It significantly increases the response characteristics of the control pressure. This paper also introduces steps and methods to realize several typical loading paths, such as constant pressure, jump pressure and additional back & differential pressure loading. These provide a new way to measure the strain rate sensitivity index m value and improve the deformation speed of superplastic free bulging.
文摘The paper studies the ground vertical deformation and the geoid undulation caused by loading of neighboring buildings, based on the loading tides theory. The influence on elevation is also considered. The results show that the ground vertical deformation and the geoid undulation both reach millimeter magnitude. Therefore, it is obvious that the building loading significantly affects the precise engineering surveying, and it must be seriously considered in application.
