Fully atomistic molecular modeling is performed on an electric field poled guest-host nonlinear optical polymer system at two different densities. The higher density ͑HD͒ represents a sub-T g system, while the lower density ͑LD͒ corresponds to a system above T g. The electric field alignment of dopants was studied by calculating ͗cos ͘ and ͗cos 3 ͘ and comparing with the theoretically predicted order parameters. For the LD system, the dipole orientational order achieved during 1.5 ns of NVT dynamics at 500 K was similar to the theoretical prediction. The applied field was also found to constrain the side group of the host, poly͑methyl methacrylate͒ ͑PMMA͒. The shape of the volume swept by the dopants was found to be less cylindrical as the field was increased. The partial radial distribution functions indicated that the dopants were likely to be located near the host side group. No significant differences in the static conformational properties of the host were observed between poled and unpoled structures. In the HD system, the COOCH 3 side group motion was found to be more correlated with dopant orientation than the atoms in the backbone units. In the LD system, nearly equal side group and backbone contributions were involved in dopant orientation.

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The climate-induced decrease in fish catches in South Korea has been a big concern over the last decades. The increase in sea surface temperature (SST) due to climate change has led to not only a decline in fishery landings but also a shift in the fishing grounds of several fish species. The habitat suitability index (HSI), a reliable indicator of the capacity of a habitant to support selected species, has been widely used to detect and forecast fishing ground formation. In this study, the catch data of the chub mackerel and satellite-derived environmental factors were used to calculate the HSI for the chub mackerel in the South Sea, South Korea. More than 80% of the total catch was found in areas with an SST of 14.72-25.72 • C, chlorophyll-a of 0.30-0.92 mg m −3 , and primary production of 523.7-806.46 mg C m −2 d −1 . Based on these results, the estimated climatological monthly HSI from 2002 to 2016 clearly showed that the wintering ground of the chub mackerel generally formed in the South Sea of South Korea, coinciding with the catch distribution during the same period. This outcome implies that our estimated HSI can yield a reliable prediction of the fishing ground for the chub mackerel in the East/Japan Sea and South Sea of South Korea.Remote Sens. 2018, 10, 938 2 of 12 currently available on the chub mackerel's favored environmental conditions in the seas around South Korea. Therefore, it is highly necessary to examine the recent reductions in catches and influence of environmental changes on fish communities. In particular, the time series investigations on chub mackerel sustainability and the major environmental parameters affecting their habitat formation are highly recommended.On the other hand, several studies from various oceanic regions have reported that the marine fish population dynamics and spatial distribution are influenced by several environmental variables, such as temperature, chlorophyll-a (Chl-a) concentration, sea surface salinity, and sea surface height anomaly [13][14][15][16]. Temperature and salinity are considered key parameters in terms of physical aspects, and Chl-a is a representative of biomass and productivity indirectly [13]. In general, sea surface height anomalies are indicators of eddies, fronts or upwelling areas [13].The habitat suitability index (HSI) has frequently been used to investigate past and current status and to predict future changes in marine fish population dynamics [13,15,[17][18][19].HSI analysis has been a useful database to establish a fishery resource management strategy in recent decades [17,20,21]. The dependency of species abundance on environmental parameters is the basic concept of the HSI model. Typically, there are a few environmental factors dominating the habitat requirements for a species. Thus, a general form of the HSI model is composed of a number of suitability indices based on the relationship of fish abundance with different environmental variables. The composite index is a non-dimensional value ranging from 0 to 1. Since the population dy...

Accurate and timely quantification of widespread harmful algal bloom (HAB) distribution is crucial to respond to the natural disaster, minimize the damage, and assess the environmental impact of the event. Although various remote sensing-based quantification approaches have been proposed for HAB since the advent of the ocean color satellite sensor, there have been no algorithms that were validated with in-situ quantitative measurements for the red tide occurring in the Korean seas. Furthermore, since the geostationary ocean color imager (GOCI) became available in June 2010, an algorithm that exploits its unprecedented observation frequency (every hour during the daytime) has been highly demanded to better track the changes in spatial distribution of red tide. This study developed a novel red tide quantification algorithm for GOCI that can estimate hourly chlorophyll-a (Chl a) concentration of Cochlodinium (Margalefidinium) polykrikoides, one of the major red tide species around Korean seas. The developed algorithm has been validated using in-situ Chl a measurements collected from a cruise campaign conducted in August 2013, when a massive C. polykrikoides bloom devastated Korean coasts. The proposed algorithm produced a high correlation (R=0.92) with in-situ Chl a measurements with robust performance also for high Chl a concentration (300mg/m) in East Sea areas that typically have a relatively low total suspended particle concentration (<0.5mg/m).