Strategies for Modelling Spherical and Aspherical Earth Structure Using Long-Period Seismic Data

这项研究是将新的建模策略应用于全球地震学中已被证明难以用常规技术解决的问题。所关注的问题是高度非线性的和/或有多个解最小值，这使得梯度技术无法使用，而一般搜索技术的成本过高。基于与自然系统优化的类比的发展导致了能够有效搜索模型空间的实用算法。这类算法包括模拟退火、遗传算法和进化规划。该算法将应用于两个具体问题：由自由振荡测量数据集建立的球对称地球模型，以及一维和三维结构的波形建模。＊＊＊

9316435 Gilbert This research is the application of new modeling strategies to problems in global seismology which have proven difficult to solve using conventional techniques. The problems of concern are highly nonlinear and/or have multiple solution minima, which makes gradient techniques unusable and general search techniques prohibitively expensive. Developments based on analogies with optimization in naturally occurring systems are leading to practical algorithms which can efficiently search model space. This class of algorithms includes simulated annealing, genetic algorithms, and evolutionary programming. The algorithms will be applied to two specific problems: spherically symmetric earth models from datasets of free-oscillation measurements, and waveform modeling of 1-D and 3-D structure. ***