Pre-selection of monitoring stations for marine water quality using affinity propagation: A case study of Xincun Lagoon, hainan, China.

The development, protection, and restoration of bays require works in scientific research and applications, and the success of which depends on a well deployment of monitoring stations for marine water quality. However, for bays without historical data, it is difficult to carry out related research on deployment of the monitoring stations, resulting in very few research works. This paper has introduced the affinity propagation (AP) clustering algorithm and achieved good results by correcting the preferences. The results show that under the given preference, that is, when the value of M is -6800, the number of monitoring stations in the Xincun lagoon area is 24. Simultaneous the sensitivity analysis of preferences shows that the number of exemplars decreases with lower preferences, that is, when M decreased from -4000 to -12000, the number also decreased from 70 to 36. However, some exemplars remain unchanged or being changed to adjacent positioning. This shows the stability of computation results and the rationality of AP. The research results can be well applied to other bays, even open waters.

On-Chip Structures for Fmax Binning and Optimization.

Process variations during manufacturing lead to differences in the performance of the chips. In order to better utilize the performance of the chips, it is necessary to perform maximum operation frequency (Fmax) tests to place the chips into different speed bins. For most Fmax tests, significant efforts are put in place to reduce test cost and improve binning accuracy; e.g., our conference paper published in ICICM 2017 presents a novel binning sensor for low-cost and accurate speed binning. However, by promoting chips placed at the lower bins, because of conservative binning, into higher bins, the overall profit can greatly increase. Therefore, this paper, extended based on a conference paper, presents a novel and adaptive methodology for speed binning, in which the paths impacting the speed bin of a specific IC are identified and adapted by our proposed on-chip Binning Checker and Binning Adaptor. As a result, some parts at a bin margin can be promoted to higher bins. The proposed methodology can be used to optimize the Fmax yield of a digital circuit when it has redundant timing in clock tree, and it can be integrated into current Fmax tests with low extra cost. The proposed adaptive system has been implemented and validated on five benchmarks from ITC, ISCAS89, and OpenSPARCT2 core on 28 nm Altera FPGAs. Measurement results show that the number of higher bin chips is improved by 7-16%, and our cost analysis shows that the profit increase is between 1.18% and 3.04%.

Trace metal contamination and species-specific bioaccumulation in the Zhoushan Fishery, northwestern East China Sea.

Metal contamination in fishery water may pose a serious threat to aquatic products and human health. In this study, the contents of seven trace metals were assessed in water, sediment, and ten commercially important species (seven fish and three crustaceans) with different trophic guilds, habitat preferences, and motility, collected from the Zhoushan Fishery, northwest East China Sea. In general, the results showed that the concentrations of trace metals in water and sediment were lower than the safety thresholds set by the National Seawater Quality Standard of China and the sediment quality guidelines, except for Cu, As, and Cr in sediment. The high metal concentrations were spatially distributed in the west of the Zhoushan Fishery, which is probably due to the chemical pollution generated from many large international ports and chemical industries in Hangzhou Bay. The metal concentrations in the species were lower than the legislation thresholds established by the Commission Regulation and China National Standard, except for Cd in two crustacean species. However, a health risk assessment indicated that the consumption of the analyzed seafood is safe. However, there is a potential risk to local consumers who prefer crustaceans. From a species-specific bioaccumulation point of view, species in high trophic guilds, benthivores, species with low motility, or those living near the sediment have been found to be most likely to accumulate metals. Our findings could contribute to the understanding of the accumulation tendencies of metals in species of different trophic guilds with varying habitat preferences and motility and provide valuable data to environmental and seafood safety managers.

Species-specific bioaccumulation of trace metals among fish species from Xincun Lagoon, South China Sea.

Xincun Lagoon is an important fishing area in northern Hainan Island, China. It has long been exposed to pollutants from local sewage, breeding cages and fishing boats, resulting in serious pollution threats to the survival of fish. In this study, we examined the concentrations of seven trace metals (Cu, Pb, Zn, Cd, Hg, As and Cr) in sixteen economic fish species collected from Xincun Lagoon and their exposed environment (water and sediment). The concentrations of Pb and Zn in the water column were higher than the safety threshold stipulated by Chinese legislation, while the contents of all examined metals in the sediment and fish species were lower than the legislative thresholds set by China and international organizations. The contents of trace metals in the fish species in high trophic levels or those that prefer to live in/on the sediment layer were significantly higher than those in other trophic levels and pelagic/subbenthic fish, these species had homogeneous anthropogenic pollution sources for Cu, Zn, Cd, Hg and As. Our results show that the trace metal contents in fish were mainly affected by trophic level and habitat preference. The contribution of metal exposure from the sediment to metal accumulation in fish was lower than that in water, especially for the Cd and Hg in the sediment. These results provide valuable information for further understanding the species-specific patterns of metal accumulation in fish and the development of targeted conservation measures for the environment and fish consumers.

Heavy metal distribution and bioaccumulation ability in marine organisms from coastal regions of Hainan and Zhoushan, China.

We analyzed the distribution and bioaccumulation of six heavy metals (Cu, Pb, Zn, Cr, Cd and Hg) in marine organisms, water, and sediments from China's Hainan and Zhoushan coastal regions. In all marine organism, seawater, and sediment samples, Zn and Hg had the highest and lowest concentrations, respectively. Heavy metals in marine organisms varied by region and species, with concentrations being higher in Zhoushan than in Hainan (except for Zn) and in crab than in fish. Marine organisms' ability to digest and eliminate heavy metals (bioaccumulation ability), based on bioaccumulation factors, was significantly higher for heavy metals in seawater than in sediment. Higher sediment background values may explain the higher heavy metal concentrations in crab. Generally, marine organisms' bioaccumulation ability was higher for Cu and Zn and lower for Pb. Findings specific to the coastal environments may be generalizable to other coastal areas in China or worldwide.

[Zooplankton community structure in relation to influencing factors in different parts of Hangzhou Bay in autumn].

Based on the data collected from three oceanographic surveys in the east area of north (30.68°-30.83° N,121.67°-121.87° E), the east area of south (29.95°-30.24° N,121.60°- 121.85° E), and the west area of north (30.58°--30.77° N,121.31°--121.56° E) Hangzhou Bay during the autumn of 2009, 2011 and 2012, we analyzed the species composition, ecological groups and the similarity of zooplankton community, as well as influencing factors. The results indicated that a total of 14 species belonging to 6 groups were identified in the west area of north Hangzhou Bay. Tortanus vermiculus was the predominant species. The zooplankton assembles were mainly influenced by the runoff strength of the Qiantang River. The zooplankton fauna was mainly composed of the subtropical estuarine brackish-water species, accounting for 79.8% in the total abundance. A total of 19 species belonging to 6 groups were identified in the east area of north Hangzhou Bay. The composition of zooplankton community was mainly influenced by the Changjiang diluted water and offshore water of the East China Sea. It was mainly composed of warm-temperature and subtropical nearshore low-salinity species, accounting for 43.5% and 31.1% in the total abundance, respectively. In the east area of south Hangzhou Bay, a total of 25 species belonging to 7 groups were identified. The composition of zooplankton community was mainly influenced by the offshore water of the East China Sea. The dominate eco-group types were subtropical nearshore low-salinity and subtropical nearshore species, accounting for 72.3% and 18.3% in the total abundance, respectively. And the ecological groups of species with the highest abundance was Labidocera sinilobata, accounting for 65.3% in the total abundance. By hierarchical cluster analysis and non-metric multidimensional scaling (NMDS) method, it was found that the zooplankton communities in the three parts of Hangzhou Bay were significantly different, which were closely associated with the impacts of different water masses from these parts.