The force model during needle insertion into soft tissue is important for accurate percutaneous intervention.In this paper,a force model for needle insertion into a tissue- equivalent material is presented and a serie...The force model during needle insertion into soft tissue is important for accurate percutaneous intervention.In this paper,a force model for needle insertion into a tissue- equivalent material is presented and a series of experiments are conducted to acquire data from needle soft- tissue interaction process.In order to build a more accurate insertion force model,the interaction force between a surgical needle and soft tissue is divided into three parts:stiffness force,friction force,and cutting force.The stiffness force is modeled on the basis of contact mechanics model.The friction force model is presented using a modified Winkler' s foundation model.The cutting force is viewed as a constant depending on a given tissue.The proposed models in the paper are established on the basis of the mechanical properties and geometric parameters of the needle and soft tissue.The experimental results illustrate that the force models are capable of predicting the needle-tissue interaction force.The force models of needle insertion can provide real-time haptic feedback for robot-assisted procedures,thereby improving the accuracy and safety of surgery.展开更多
China has a long tradition of cadre education and training （CET） , which has developed to be a particular Chinese way of executive development highlighting rigorbus and systematic organization by the Chinese Communi...China has a long tradition of cadre education and training （CET） , which has developed to be a particular Chinese way of executive development highlighting rigorbus and systematic organization by the Chinese Communist Party （CCP） and a dual emphasis on political-ideological work and knowledge-capacity building. This paper offers an overview of the historical development of CET, and generalizes its managing system, training system, targeted cadres, training contents and institutionalization. The functions of CET are classified as formal including political （re-） engineering and capacity and knowledge building, and informal including collective identity and social connections. The Shanghai Municipal Committee Party School is further studied regarding its educational programs, especially the planned programs, contents of training, trainers, financing, and quality assurance. It is argued that in response to challenges in an era of globalization, CET has worked both to consolidate the political authority of the CCP and enhance governmental officials＇ awareness and knowledge of governing issues and their problem-solving capacities. As a result CET itself has been undergoing continuous adjustments.展开更多
基金Supported by the National Natural Science Foundation of China(No.51175373)New Century Educational Talents Plan of Chinese Education Ministry(No.NCET-10-0625)+1 种基金Key Technology and Development Program of Tianjin Municipal Science and Technology Commission(No.12ZCDZSY10600)Tianjin Key Laboratory of High Speed Cutting&Precision Machining(TUTE)(2013120024001167)
文摘The force model during needle insertion into soft tissue is important for accurate percutaneous intervention.In this paper,a force model for needle insertion into a tissue- equivalent material is presented and a series of experiments are conducted to acquire data from needle soft- tissue interaction process.In order to build a more accurate insertion force model,the interaction force between a surgical needle and soft tissue is divided into three parts:stiffness force,friction force,and cutting force.The stiffness force is modeled on the basis of contact mechanics model.The friction force model is presented using a modified Winkler' s foundation model.The cutting force is viewed as a constant depending on a given tissue.The proposed models in the paper are established on the basis of the mechanical properties and geometric parameters of the needle and soft tissue.The experimental results illustrate that the force models are capable of predicting the needle-tissue interaction force.The force models of needle insertion can provide real-time haptic feedback for robot-assisted procedures,thereby improving the accuracy and safety of surgery.
文摘China has a long tradition of cadre education and training （CET） , which has developed to be a particular Chinese way of executive development highlighting rigorbus and systematic organization by the Chinese Communist Party （CCP） and a dual emphasis on political-ideological work and knowledge-capacity building. This paper offers an overview of the historical development of CET, and generalizes its managing system, training system, targeted cadres, training contents and institutionalization. The functions of CET are classified as formal including political （re-） engineering and capacity and knowledge building, and informal including collective identity and social connections. The Shanghai Municipal Committee Party School is further studied regarding its educational programs, especially the planned programs, contents of training, trainers, financing, and quality assurance. It is argued that in response to challenges in an era of globalization, CET has worked both to consolidate the political authority of the CCP and enhance governmental officials＇ awareness and knowledge of governing issues and their problem-solving capacities. As a result CET itself has been undergoing continuous adjustments.
