基于自适应模拟退火算法的生物体三维温度场重构研究

Research on 3D Temperature Field in Biological Tissue Based on Adaptive Simulated Annealing Algorithm

生物体三维温度场的无损重构对于生物医学工程领的发展有着十分重要的意义。提出基于自适应模拟退火算法进行生物体三维温度场无损重构的重要思想,把复杂的生物热传导反问题的求解转换为正问题的求解过程。设生物体内点热源的位置P(x,y,z)和温度t为优化变量,把同一表面各个对应点的试验温度值和计算温度值相减并取绝对值之和,以此为目标函数逐次迭代。目标值越小,则当前变量,即热源位置和温度值最优。为了提高优化效率,提出一种新颖的目标函数建立方法。热源的仿真位置和试验位置十分接近。最优值确定后,相应的三维温度场也随之确定,任意截面的温度分布可以提取出来。自适应模拟退火算法可以很好地应用于生物体三维温度场的重构,它不仅方便,而且快捷,蕴藏着广阔的应用前景,热传导反问题的研究提供了一条具有借鉴性的方法与思路。

The research on nondestructive reconstruction of 3D temperature field in biological possesses great significance for the biomedical engineering field. A novel method presented about the nondestructive reconstruction of 3D temperature field in biological tissue based on adaptive simulated annealing（ASA） algorithm. By this method, the resolving of inverse problem of bio-heat transfer is transformed to be a solving process of direct problem. Set the position P（x, y, z） of point heat source in biological tissue and its temperature t as optimization variables, get the experimental temperature values of the points in a module surface subtract form the corresponding simulating temperature values in the same module surface, and then take the sum of absolute value. Taking it as the objective function of successive iteration, if the target value is less, the current variables are more optimal. To improve the optimization efficiency, a novel establishment method of objective function is also provided. The simulating position and experimental position of heat source is very approximate. When the optimum values are determined, the corresponding 3D temperature field is also confirmed, and the temperature distribution of arbitrary section can be acquired. The ASA algorithm can be well applied in the reconstruction of 3D temperature field in biological tissue. It is convenient and speedy, and contains capacious application prospect.