Tian-Chyi Jim Yeh

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[1] Hydraulic tomography is a cost-effective technique for characterizing the heterogeneity of hydraulic parameters in the subsurface. During hydraulic tomography surveys a large number of hydraulic heads (i.e., aquifer responses) are collected from a series of pumping or injection tests in an aquifer. These responses are then used to interpret the spatial(More)
[1] Two large-scale cross-hole pumping tests were conducted at depths of 191–226 m and 662–706 m in deep boreholes at the Mizunami Underground Research Laboratory (MIU) construction site in central Japan. During these two tests, induced groundwater responses were monitored at many observation intervals at various depths in different boreholes at the site.(More)
[1] Knowledge of unsaturated zone hydraulic properties is critical for many environmental and engineering applications. Various stochastic methods have been developed during the past 2 decades to estimate the effective unsaturated hydraulic properties. Independent of these stochastic methods, we develop in this paper a practical approach to estimate the(More)
[1] Transient hydraulic tomography (THT) is a potentially cost-effective and highresolution technique for mapping spatial distributions of the hydraulic conductivity and specific storage in aquifers. Interpretation of abundant well hydrographs of a THT survey, however, is a computational challenge. We take on this challenge by developing an estimation(More)
Over the past few decades, enormous effort has been expended on conducting traditional aquifer tests and model calibration for characterizing aquifers. Traditional aquifer tests generally involve pumping at one well and using the observed drawdown data at another well to estimate aquifer hydraulic properties. Analysis of the test is built upon Theis’ or(More)
Gray system theory uses a black-gray-white color spectrum to describe a complex system whose characteristics are only partially known or known with uncertainty. In this study, we use gray system theory to investigate the relation between precipitation and spring flows in a karst region in China. The gray incidence analysis was applied to the Liulin Springs,(More)
[1] A new technology, hydraulic/partitioning tracer tomography (HPTT), is proposed to survey spatial distributions of hydraulic properties and dense nonaqueous phase liquids (DNAPLs) in the subsurface. HPTT is nothing more than a set of multiple hydraulic/ partitioning tracer tests and synthesis of all the tests to map the spatial distributions. It involves(More)
[1] In this study, a geostatistically based estimator is developed that simultaneously includes all observed transient hydrographs from hydraulic tomography to map aquifer heterogeneity. To analyze tomography data, a data preprocessing procedure (including diagnosing and wavelet denoising analysis) is recommended. A least squares approach is then introduced(More)
[1] A vadose zone field injection experiment was conducted in the summer of 2000 at the Hanford Site, Washington. The unique moisture content (q) database is used to identify the lithology at the field site and to interpret, visualize, and quantify the spatiotemporal evolution of the three-dimensional (3-D) moisture plume created by the injection(More)
There are approximately 470,000 km(2) of karst aquifers that feed many large springs in North China. Turbulent flow often exists in these karst aquifers, which means that the classical ground water model based on Darcy's law cannot be applied here. Ground water data are rare for these aquifers. As a consequence, it is difficult to quantitatively investigate(More)