The pyramidal multiphase level set framework (PMLSF) based on the technique of painting background (TPBG) and the Chan-Vese model can detect multiple objects on a given image. However, the boundaries of the sub-ob...The pyramidal multiphase level set framework (PMLSF) based on the technique of painting background (TPBG) and the Chan-Vese model can detect multiple objects on a given image. However, the boundaries of the sub-object obtained by PMLSF-TPBG are not variable since a specialcolor parameter is used in TPBG. To solve the problem, a new technique utilizing a varying parameter is proposed to ensure that PMLSF is effective for the detection of the desired boundaries of the sub-object. The interval of the variable color parameter is proved and the effects of the parameter are also discussed. Experimental results for the brain tumor detection show that different boundaries of the brain tumors can be detected with different color parameters. It is especially useful for clinical diagnoses.展开更多
A new multi-phase active contour model is proposed for the image segmentation. It is a generalization of the C-V model with the following characteristics: (1) A key technique, called the technique of painting backg...A new multi-phase active contour model is proposed for the image segmentation. It is a generalization of the C-V model with the following characteristics: (1) A key technique, called the technique of painting background (TPBG), is developed to remove the information of the background, which blocks the detection of weak boundaries in the object; (2) The two-phase level set is applied multiple times for getting the multi-phase segmentation model (n-1 times for the n-phase model, n〉1); (3) A scaling-based method is introduced to improve the basic model. Experimental results show that the proposed model is effective for detecting weak boundaries.展开更多
An experimental study was conducted to quantify the flow characteristics of the wall jets pertinent to trailing edge cooling of turbine blades.A high-resolution stereoscopic particle image velocimetry(PIV)system was u...An experimental study was conducted to quantify the flow characteristics of the wall jets pertinent to trailing edge cooling of turbine blades.A high-resolution stereoscopic particle image velocimetry(PIV)system was used to conduct detailed flow field measurements to quantitatively visualize the evolution of the unsteady vortices and turbulent flow structures in the cooling wall jet streams and to quantify the dynamic mixing process between the cooling jet stream and the mainstream flows.The detailed flow field measurements were correlated with the adiabatic cooling effectiveness maps measured by using pressure sensitive paint(PSP)technique to elucidate underlying physics in order to explore/optimize design paradigms for improved cooling effectiveness to protect the critical portions of turbine blades from harsh environments.展开更多
文摘The pyramidal multiphase level set framework (PMLSF) based on the technique of painting background (TPBG) and the Chan-Vese model can detect multiple objects on a given image. However, the boundaries of the sub-object obtained by PMLSF-TPBG are not variable since a specialcolor parameter is used in TPBG. To solve the problem, a new technique utilizing a varying parameter is proposed to ensure that PMLSF is effective for the detection of the desired boundaries of the sub-object. The interval of the variable color parameter is proved and the effects of the parameter are also discussed. Experimental results for the brain tumor detection show that different boundaries of the brain tumors can be detected with different color parameters. It is especially useful for clinical diagnoses.
文摘A new multi-phase active contour model is proposed for the image segmentation. It is a generalization of the C-V model with the following characteristics: (1) A key technique, called the technique of painting background (TPBG), is developed to remove the information of the background, which blocks the detection of weak boundaries in the object; (2) The two-phase level set is applied multiple times for getting the multi-phase segmentation model (n-1 times for the n-phase model, n〉1); (3) A scaling-based method is introduced to improve the basic model. Experimental results show that the proposed model is effective for detecting weak boundaries.
文摘An experimental study was conducted to quantify the flow characteristics of the wall jets pertinent to trailing edge cooling of turbine blades.A high-resolution stereoscopic particle image velocimetry(PIV)system was used to conduct detailed flow field measurements to quantitatively visualize the evolution of the unsteady vortices and turbulent flow structures in the cooling wall jet streams and to quantify the dynamic mixing process between the cooling jet stream and the mainstream flows.The detailed flow field measurements were correlated with the adiabatic cooling effectiveness maps measured by using pressure sensitive paint(PSP)technique to elucidate underlying physics in order to explore/optimize design paradigms for improved cooling effectiveness to protect the critical portions of turbine blades from harsh environments.