Camera calibration is a critical process in photogrammetry and a necessary step to acquire 3D information from a 2D image. In this paper, a flexible approach for CCD camera calibration using 2D direct linear transform...Camera calibration is a critical process in photogrammetry and a necessary step to acquire 3D information from a 2D image. In this paper, a flexible approach for CCD camera calibration using 2D direct linear transformation （DLT） and bundle adjustment is proposed. The proposed approach assumes that the camera interior orientation elements are known, and addresses a new closed form solution in planar object space based on homogenous coordinate representation and matrix factorization. Homogeneous coordinate representation offers a direct matrix correspondence between the parameters of the 2D DLT and the collinearity equation. The matrix factorization starts by recovering the elements of the rotation matrix and then solving for the camera position with the collinearity equation. Camera calibration with high precision is addressed by bundle adjustment using the initial values of the camera orientation elements. The results show that the calibration precision of principal point and focal length is about 0.2 and 0.3 pixels respectivelv, which can meet the requirements of close-range photogrammetry with high accuracy.展开更多
This job focuses on the stroke regulation of a class of high-precision metering pumps.A parametertuning method of robust non-fragile PID（proportional-integral-derivative）controllers is proposed with the assumption t...This job focuses on the stroke regulation of a class of high-precision metering pumps.A parametertuning method of robust non-fragile PID（proportional-integral-derivative）controllers is proposed with the assumption that a PID controller has additive gain perturbations.An H-infinite robust PID controller can be obtained by solving a linear matrix inequality.This approach can guarantee that the closed-loop control systems is asymptotically stable and the H-infinite norm of the transfer function from the disturbance to the output of a controlled system is less than a given constant to attenuate disturbances.The simulation case shows that the control performance of the proposed strategy is significantly better than the traditional PID approach in the situation with perturbations of controller parameters.展开更多
Primary and secondary networks are treated as a whole in indirect heating systems, and an advanced new temperature-flow regulation method is presented whose flow ratio is greater than 60% in a secondary network and 30...Primary and secondary networks are treated as a whole in indirect heating systems, and an advanced new temperature-flow regulation method is presented whose flow ratio is greater than 60% in a secondary network and 30% in a primary network when under a partial load. Through deducing and optimizing an exponential function flow regulation rule, the formulae of flow regulation and the supply and return water temperatures are obtained, and their relevant curves are plotted. After comparison, it is found that this control method has a huge energy conservation space, and it should therefore be generalized soon.展开更多
From the very beginning, auditing is pretty much a self-regulated follow in practice. But the plethora of recent corporate failures profession and has some ethical rules of thumb to and scandals where auditors＇ instr...From the very beginning, auditing is pretty much a self-regulated follow in practice. But the plethora of recent corporate failures profession and has some ethical rules of thumb to and scandals where auditors＇ instrumental role is evident in many instances raise question about the validity and suitability of ＂self-regulation＂ in auditing, especially in the 21st century where auditors need to perform auditing in ever complex risk management process. Moreover, to restore the market confidences within the auditing profession and to raise the overall audit quality, many countries are establishing some super regulatory bodies to oversee the functions of auditing and auditors. Based on the ＂documentary research methodology＂, the author examines whether ＂self-regulation＂ in auditing has completely failed in the 21 st century. The author reveals that ＂self-regulation＂ in auditing has not completely failed; rather, a joint approach is needed to raise the overall quality of auditing where there will be equilibrium between ＂self-regulation＂ and statutory directive.展开更多
基金Project 2005A030 supported by the Youth Science and Research Foundation from China University of Mining & Technology
文摘Camera calibration is a critical process in photogrammetry and a necessary step to acquire 3D information from a 2D image. In this paper, a flexible approach for CCD camera calibration using 2D direct linear transformation （DLT） and bundle adjustment is proposed. The proposed approach assumes that the camera interior orientation elements are known, and addresses a new closed form solution in planar object space based on homogenous coordinate representation and matrix factorization. Homogeneous coordinate representation offers a direct matrix correspondence between the parameters of the 2D DLT and the collinearity equation. The matrix factorization starts by recovering the elements of the rotation matrix and then solving for the camera position with the collinearity equation. Camera calibration with high precision is addressed by bundle adjustment using the initial values of the camera orientation elements. The results show that the calibration precision of principal point and focal length is about 0.2 and 0.3 pixels respectivelv, which can meet the requirements of close-range photogrammetry with high accuracy.
基金Supported by the National Natural Science Foundation of China（60604015） the Key Research Program of Education Department of Zhejiang Province（Z200803521）
文摘This job focuses on the stroke regulation of a class of high-precision metering pumps.A parametertuning method of robust non-fragile PID（proportional-integral-derivative）controllers is proposed with the assumption that a PID controller has additive gain perturbations.An H-infinite robust PID controller can be obtained by solving a linear matrix inequality.This approach can guarantee that the closed-loop control systems is asymptotically stable and the H-infinite norm of the transfer function from the disturbance to the output of a controlled system is less than a given constant to attenuate disturbances.The simulation case shows that the control performance of the proposed strategy is significantly better than the traditional PID approach in the situation with perturbations of controller parameters.
文摘Primary and secondary networks are treated as a whole in indirect heating systems, and an advanced new temperature-flow regulation method is presented whose flow ratio is greater than 60% in a secondary network and 30% in a primary network when under a partial load. Through deducing and optimizing an exponential function flow regulation rule, the formulae of flow regulation and the supply and return water temperatures are obtained, and their relevant curves are plotted. After comparison, it is found that this control method has a huge energy conservation space, and it should therefore be generalized soon.
文摘From the very beginning, auditing is pretty much a self-regulated follow in practice. But the plethora of recent corporate failures profession and has some ethical rules of thumb to and scandals where auditors＇ instrumental role is evident in many instances raise question about the validity and suitability of ＂self-regulation＂ in auditing, especially in the 21st century where auditors need to perform auditing in ever complex risk management process. Moreover, to restore the market confidences within the auditing profession and to raise the overall audit quality, many countries are establishing some super regulatory bodies to oversee the functions of auditing and auditors. Based on the ＂documentary research methodology＂, the author examines whether ＂self-regulation＂ in auditing has completely failed in the 21 st century. The author reveals that ＂self-regulation＂ in auditing has not completely failed; rather, a joint approach is needed to raise the overall quality of auditing where there will be equilibrium between ＂self-regulation＂ and statutory directive.
