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It was found that bypass graft alone could achieve great effects in treating aortic dissection. In order to investigate the mechanical mechanism and the haemodynamic validity of the bypassing treatment for DeBakey III aortic dissection, patient-specific models of DeBakey III aortic dissection treated with different bypassing strategies were constructed. One of the bypassing strategies is bypassing between ascending aorta and abdominal aorta, and the other is bypassing between left subclavian artery and abdominal aorta. Numerical simulations under physiological flow conditions based on fluid-structure interaction were performed using finite element method. The results show that blood flow velocity, pressure and vessel wall displacement of false lumen are all reduced after bypassing. This phenomenon indicates that bypassing is an effective surgery for the treatment of DeBakey III aortic dissection. The effectiveness to cure through lumen is better when bypassing between left subclavian artery and abdominal aorta, while the effectiveness to cure blind lumen is better when bypassing between ascending aorta and abdominal aorta.

In the process of oil exploitation, the water level of an oil well can be predicted and the position of reservoir can be estimated by measuring the water content of crude oil, with reference for the automatic production of high efficiency in the oil field. In this paper, a visual measuring method for water content of crude oil is proposed. The oil and water in crude oil samples were separated by centrifugation, distillation or electric dehydration, and a water–oil layered mixture was formed according to the unequal densities. Then the volume ratio of water and oil was analyzed by digital image processing, and the water content and oil content was able to be calculated. A new method for measuring water content of crude oil based on IGAVD (image grayscale accumulated value difference) is proposed, which overcomes the uncertainty caused by environmental illumination and improves the measurement accuracy. In order to verify the effectiveness of the algorithm, a miniaturization and low-cost system prototype was developed. The experimental results show that the average power consumption is about 165 mW and the measuring error is less than 1.0%. At the same time, the real-time and remote transmission about measurement results can be realized.

To investigate the influence of bypassing treatment on the hemodynamic parameters of aortic dissection and the feasibility of this therapeutic approach in clinical application, idealized three-dimensional geometric models of DeBakey III aortic dissection with a blind lumen and its bypassing treatment were constructed with the software of SolidWorks 2007. Then, numerical simulation was performed utilizing the software of ANSYS 11.0, and the results were analyzed. The velocity of blood flow and the pressure at the entrance area of false lumen and in the false lumen are both less than those before the operation. Bypassing is an effective surgery for the treatment of DeBakey III dissection. It can effectively reduce the pressure of aortic arch and ease the impulsion and stress of blood flow on the pathological dissection. It can also alleviate the propagation, prevent the rupture, and promote the healing of dissection.

In order to investigate the validity of bypassing treatment for aortic dissection, two-dimensional idealized geometry models of DeBakey III aortic dissection and its bypassing treatment were constructed. Computational simulations of physiological blood flow in these models were performed with the software of ANSYS using finite element method. After bypassing treatment, the blood flow velocity and the pressure in the false lumen of aortic dissection are both less than those before the operation. Bypassing can effectively reduce the pressure of aortic arch and ease the impulsion and stress of blood flow on the pathological dissection. Bypassing is an prospective surgical approach for the treatment of DeBakey III aortic dissection.