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Abstract: This paper presents a novel effective method for optimizing laser cutting of specially shaped electronic printed circuit board (PCB) carrier substrates of advanced integrated circuit (IC) back-end packages that have multiple performance characteristics identified using grey relational analysis (GRA). Laser cutting parameters, including laser beam parameters (average laser power and Q-switch frequency), focusing parameters (laser beam focusing spot size), and machine parameters (laser cutting speed), were optimized based on multiple performance characteristics. Some characteristics of the specially shaped flash memory module for IC packages, such as smart disk (SD) cards are verified. The characteristics of interest are the average surface roughness on a PCB substrate cross-section, and the maximum width of the heat-affected zone (HAZ). Eight experiments were conducted using GRA to optimize the settings for laser beam cutting parameters to generate various quality characteristics. Analysis of the grey relational grade indicates that parameter significance and the optimal parameter combination for the laser cutting process are identified. The analytical results from two confirmation experiments using the optimal parameters confirm that laser cutting technology can be effectively applied to cut substrates into special shapes. [Copyright &y& Elsevier]

• Marine ranching ecological efficiency (MREE) is defined within production and ecology. • Evaluation index system for MREE is constructed from the view of inputs and outputs. • Super-SBM model that considering undesired outputs is employed to evaluate MREE. • Case study of Shandong is performed to evaluate and analyze the MREE. • Several suggestions are proposed to improve the MREE for Shandong Province. To investigate the efficiency level of marine ranching in the process of ecological management and the balance between the economy and ecology, we proposed a comprehensive index system based on the entropy weight method and measured the Marine Ranching Ecological Efficiency (MREE) of 18 marine ranches in Shandong Province through the Super-SBM model. On the basis of MREE scores, we divided the marine ranches into high-efficiency, medium-efficiency and low-efficiency marine ranches and carried out a comparative analysis. Then, we performed a cause analysis of the efficiency loss. The results showed that the mean of the MREE scores was 0.6; the best-practice marine ranching had an MREE score of 1.877 while the worst one had an MREE score of 0.0645, wherein the Pure Technical Efficiency (PTE) score was the key dimension between the decomposition efficiency scores of MREE scores respected by the Technical Efficiency (TE) scores. The result indicates that the redundancy of inputs and undesirable outputs and the deficiency of ecological outputs are major causes of loss of MREE, which reflects inefficient resource allocation efficiency, deficient government and technical support, and inadequate habitat construction and risk prevention of these marine ranches. [ABSTRACT FROM AUTHOR]