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Ground Water. 2010 Jul-Aug;48(4):604-8. doi: 10.1111/j.1745-6584.2009.00650.x. Epub 2009 Nov 20.
Parameter-estimation methods, including an exhaustive-search method and PEST (Parameter ESTimation) software, were applied to recovery-test data and slug-test data to obtain best estimates of transmissivity (T) by minimizing the sums of residuals. Each residual represents the difference between the field-measured water-level value and the value calculated by the appropriate non-linear equation. The exhaustive-search method in both cases involves computing the sums of residuals for an array of transmissivity and storativity values selected by the user for testing. Two new Fortran programs are presented that employ the exhaustive-search method. They utilize Picking's method for analyzing recovery-test data and the analytical equation for analyzing slug-test data derived by Cooper, Bredehoeft, and Papadopulos. Picking's method involves application of the Papadopulos and Cooper's equation for drawdown in finite-diameter wells. Utilizing field data reported in the literature, the estimated transmissivity values from the exhaustive-search methods were compared to the literature values obtained by type-curve matching techniques. The exhaustive-search values corresponded closely to the curve-matching values. Estimates for T were also obtained from recovery-test and slug-test data from two sites in southeastern Pennsylvania. For these sites, the PEST program was also applied to the data to evaluate the accuracy of the exhaustive-search methods. The results from the two methods were generally in good agreement. The two new Fortran programs are practical tools for the hydrogeologist, as they require less time compared to type-curve matching and the PEST method, and they yield accurate estimates of transmissivity.
参数估计方法，包括穷举搜索法和 PEST（参数估计）软件，被应用于恢复试验数据和柱塞试验数据，以通过最小化残差总和来获得渗透率（T）的最佳估计值。每个残差代表现场测量的水位值与适当的非线性方程计算的值之间的差异。在这两种情况下，穷举搜索法都涉及到计算用户选择的一系列渗透率和储容率值的残差总和，以进行测试。本文提出了两个新的 Fortran 程序，它们采用穷举搜索法。它们利用皮金（Picking）法分析恢复试验数据，以及库珀（Cooper）、布瑞德霍夫特（Bredehoeft）和帕帕多普洛斯（Papadopulos）推导的分析柱塞试验数据的解析方程。皮金法涉及应用帕帕多普洛斯和库珀在有限直径井中的降落方程。利用文献中报告的现场数据，将穷举搜索法得到的渗透率估计值与文献中通过类型曲线匹配技术得到的值进行了比较。穷举搜索值与曲线匹配值非常吻合。还从宾夕法尼亚州东南部的两个地点的恢复试验和柱塞试验数据中获得了 T 的估计值。对于这些地点，还将 PEST 程序应用于数据，以评估穷举搜索方法的准确性。两种方法的结果通常非常一致。这两个新的 Fortran 程序是水文地质学家的实用工具，因为与类型曲线匹配和 PEST 方法相比，它们需要的时间更少，并且可以准确估计渗透率。
