Cheng-Haw Lee

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Due to the funding scale and complexity of lubricant regenerative technology, the selection of recycling technology and policy for waste lubricant oil can be viewed as a multiple-attribute decision process that is normally made by a review committee with experts from academia, industry, and the government. This study aims to provide a systematic approach(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)
Fracture zones and their connectivity in geologic media are of great importance to ground water resources management as well as ground water contamination prevention and remediation. In this paper, we applied a recently developed hydraulic tomography (HT) technique and an analysis algorithm (sequential successive linear estimator) to synthetic fractured(More)
[1] In this opinion paper we contend that high-resolution characterization, monitoring, and prediction are the key elements to advancing and reducing uncertainty in our understanding and prediction of subsurface processes at basin scales. First, we advocate that recently developed tomographic surveying is an effective and high-resolution approach for(More)
Streamflow is an important factor in the study of water resource management, floods, and droughts. Dramatic climate change has created extreme rainfall distributions, making the study of streamflow trends and variability even more crucial. In this study, the long-term streamflow data and trends recorded at gauging stations in Northern Taiwan are analyzed(More)
Ozone sensitivity was investigated using CAMx simulations and photochemical indicator ratios at three sites (Pingtung City, Chao-Chou Town, and Kenting Town) in Pingtung County in southern Taiwan during 2003 and 2004. The CAMx simulations compared fairly well with the hourly concentrations of ozone. Simulation results also showed that Pingtung City was(More)
A physically motivated model is indispensable for a successful analysis of the impact of leaching from nuclear waste storage sites on the environment and public health. While most analyses use the single-phase flow model for modelling unsaturated flow and solute transport, the two-phase flow model considering the resistance of gas to water flow is a more(More)
In this study, the stable isotope values of oxygen and hydrogen were used to identify the seasonal contribution ratios of precipitation to groundwater recharge in the Hualien River basin of eastern Taiwan. The differences and correlations of isotopes in various water bodies were examined to evaluate the groundwater recharge sources for the Hualian River(More)
In recent years, global climate change has altered precipitation patterns, causing uneven spatial and temporal distribution of precipitation that gradually induces precipitation polarization phenomena. Taiwan is located in the subtropical climate zone, with distinct wet and dry seasons, which makes the polarization phenomenon more obvious; this has also led(More)
a r t i c l e i n f o Keywords: Fractures Fracture network model Crack permeability tensor Ingrowth-decay transport Lan-Yu island Taiwan Very efficient and practical models that use a crack tensor in terms of fracture geometry parameters for field rock mass are proposed. A framework of the crack tensor approach combined with the identifying(More)