Evaluation and optimization of mariculture ecological efficiency under technological heterogeneity - New evidence from China's coastal regions.

This paper combines the meta-frontier analysis framework with the SBM-DEA model based on undesirable outputs to thoroughly reveal the mechanism of ecological efficiency differences in China's mariculture. This paper accurately identifies the weak links in ecological efficiency in various regions, thereby achieving a precise evaluation of mariculture ecological efficiency within the framework of technological heterogeneity. The results indicate that under the meta-frontier, the annual average ecological efficiency of mariculture in coastal areas of China during the sample period is 0.586, with a 41.4 % efficiency improvement space. However, under the group frontier, the annual average ecological efficiency is 0.783. The MEI in the BR economic zone and the YRD economic zone respectively stem from MI and TI, whereas in the PRD economic zone, the difference in the proportions of management inefficiency and technological inefficiency is not significant. Finally, this paper proposes four types of improvement paths.

Ghost translation: an end-to-end ghost imaging approach based on the transformer network.

Artificial intelligence has recently been widely used in computational imaging. The deep neural network (DNN) improves the signal-to-noise ratio of the retrieved images, whose quality is otherwise corrupted due to the low sampling ratio or noisy environments. This work proposes a new computational imaging scheme based on the sequence transduction mechanism with the transformer network. The simulation database assists the network in achieving signal translation ability. The experimental single-pixel detector's signal will be 'translated' into a 2D image in an end-to-end manner. High-quality images with no background noise can be retrieved at a sampling ratio as low as 2%. The illumination patterns can be either well-designed speckle patterns for sub-Nyquist imaging or random speckle patterns. Moreover, our method is robust to noise interference. This translation mechanism opens a new direction for DNN-assisted ghost imaging and can be used in various computational imaging scenarios.

Realizing the Improvement of Green Total Factor Productivity of the Marine Economy-New Evidence from China's Coastal Areas.

Paying attention to the mechanisms of the GTFP of the marine economy and designing a scientific and reasonable optimization path are the keys to achieving a "win-win" balance between environmental protection and high-quality marine development. Therefore, this paper considers the rigid constraints of resources and negative environmental effects to construct a multi-factor evaluation model of the GTFP of the marine economy including capital, labor, and resources to expand the evaluation method system for the sustainable development of the marine economy. On this basis, this paper determines the influencing factors of the GTFP of China's marine economy, qualitatively analyzes the mechanism of each influencing factor on the GTFP of the marine economy, uses multi-dimensional data of coastal areas, quantitatively analyzes the direct and indirect effects of the factors that influence the GTFP, and proposes practical optimization paths and safeguarding measures, which provide a decision-making reference for the implementation of China's marine development strategy. The results showed that the GTFP of China's marine economy was in a state of improvement and increased from 0.9878 in 2006 to 1.2789 in 2018. The direct effects of environmental regulations have a negative and significant impact on GTFP, whereas economic development, human capital, and technological innovations have a positive and significant impact on GTFP. In addition, environmental regulations have an "inclined N" double-threshold effect on GTFP. The impact of environmental regulations on the GTFP of the marine economy depends on the intensity of the environmental regulations, as different intensities of environmental regulations have different dominant levels of the "innovation compensation effect" and "offset effect" that affect the GTFP of the marine economy.

Study on the removable carbon sink estimation and decomposition of influencing factors of mariculture shellfish and algae in China-a two-dimensional perspective based on scale and structure.

Facing the dual pressure of economic development and ecological environmental protection, it is undoubtedly a good strategy to strengthen energy conservation and emission reduction while further increasing carbon sink. The contribution of forest carbon sink is well-known, but the carbon sink function of mariculture is rarely known. Based on the statistics of China's fishery department and the quality assessment method, this paper constructed a preliminary accounting system for the removable carbon sink of mariculture shellfish and algae, and estimated its capacity in China from 2005 to 2017. On this basis, the logarithmic mean Divisia index was used to analyze the effects of structure and scale factors on the removable carbon sink of mariculture shellfish and algae. The results showed that the annual average removable carbon sink of shellfish and algae in China's mariculture reached 92.7 ten thousand tons, and the overall trend was upward. The total removable carbon sink of shellfish was greater than that of algae. Among them, Grassastrea gigas was the main source of removable carbon sink in China's mariculture, followed by Ruditapes philippinarum. The economic value of annual removable carbon sink of mariculture shellfish and algae in China was equivalent to 139-556 million dollars. Furthermore, the scale factor plays a leading role in the removable carbon sink capacity of mariculture in China, while the structure factor plays a minor role.