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The Geostationary Ocean Color Imager (GOCI) is widely employed in tracking diurnal dynamics of oceanic conditions. However, the current atmospheric correction (AC) algorithms for GOCI often mask pixels around cloud edges to exclude pixels contaminated by cloud edge effects (CEEs; including stray light, cloud shadows, and cloud adjacent effects (AEs)), which results in massive data loss. In this paper, we propose a novel AC algorithm to correct these CEE-affected pixels based on deep learning (namely, DLACC) to achieve a comparable quality level to those pixels far away from cloud edges. We used the standard near-infrared iterative AC algorithm in SeaDAS (namely, NIR) to obtain Rayleigh-corrected reflectance (R rc) and remote sensing reflectance (R rs). Then, high-quality R rs values were extracted using a quality assurance (QA) algorithm. Next, we obtained 2,821,668 matchups by matching CEE-free noontime R rs values with CEE-affected R rc values in a time window of 1 h. These matchups were used to develop DLACC. Validations using in situ data from Aerosol Robotic Network-Ocean Color (AERONET-OC) stations showed that more matchups were obtained with the DLACC model than with the NIR algorithm and Korea Ocean Satellite Center standard AC algorithm in GDPS 2.0 (KOSC), and the accuracies were similar. More importantly, the DLACC algorithm is more tolerant of AEs and reduces AEs in a 2-pixel distance from cloud edges by 10% in the blue bands and by 50% in the green band. As a result, more valid observations are obtained with the DLACC algorithm, with the daily percentage of valid observations (DPVOs) increasing by 71% and 62% over those with the NIR algorithm and the KOSC algorithm, respectively. These increases in valid observations could further result in more consistent patterns in terms of space and time. Our DLACC algorithm can not only be used to process GOCI images but also provide an open framework to develop corresponding deep-learning models for other geostationary satellites. [ABSTRACT FROM AUTHOR]

• Development of an in-line near-infrared spectroscopy (NIR) system capable of measuring in real time the composition of polymer blends at various locations of a twin screw extruder. • Assessment of accuracy and robustness of the in-line NIR system under various operating conditions. • Use of the NIR system to study the effects of the geometry of mixing screw elements on the amplitude of compositional fluctuation and mixedness of polymer blends. Polymer blending is often conducted in the molten state using a twin screw extruder because the atom efficiency can reach nearly 100%. One of the challenges it faces is that the composition of a polymer blend at the die exit may fluctuate to an unacceptable extent. The amplitude of compositional fluctuation depends very much on mixing inside the twin screw extruder. This work aims to develop an in-line near-infrared spectroscopy (NIR) system to measure in real time the composition of polystyrene (PS) and polyolefin elastomer (POE) blends at various locations of the twin screw extruder. The accuracy and robustness of the in-line NIR system are examined under various operating conditions (POE content, barrel temperature, screw rotation speed and feeding rate). It is then used to study the effects of the geometry of mixing screw elements on the amplitude of compositional fluctuation and mixedness (the state of dispersion and distribution of one phase in another) of the polymer blend. [ABSTRACT FROM AUTHOR]

Human-transformed agricultural and aquacultural ponds, collectively referred to as "dike-pond systems", play a crucial role in ensuring food security but also contribute to the widespread loss of natural wetlands. However, spatially and temporally explicit patterns of dike-pond systems have not been thoroughly documented globally. Here, we map the distribution of dike-pond systems over both global inland and coastal regions during three periods (1984 to 2000, 2001 to 2010, 2011 to 2020) using 30-m resolution satellite observations. Results show that the total area of dike-pond systems was 132,886 km2 globally, with about 2/3 contributed from inland wetlands. From 1984 to 2020, the net gain of inland dike-pond systems (26,385 km2 or 92.7%) was 1.6 times that of coastal wetlands (16,371 km2 or 83.3%), due primarily to reduced coastal dike-pond systems in the last decade. We identified significant contributions of dike-pond systems to fishery production, and further revealed occurrences of dike-pond systems within protected areas. Our study highlights the importance of prioritizing the conservation and management of more intensively inland dike-pond systems, and our global synthesis provides a critical benchmark for assessing potential consequences of dike-pond system and for future restoration efforts. • From 1984 to 2020, about 132,886 km2 of land was transformed into dike-pond systems. • The rise of inland dike-pond systems outpaced that of coastal ones from 1984 to 2020. • 6% of inland and 14% of coastal dike-pond systems are within protected areas recently. [ABSTRACT FROM AUTHOR]

River ice plays a crucial role in hydrology, ecosystems, and socio-economic systems in mid-to-high latitude regions. However, there is a notable gap in the analysis of patterns and trends in river ice phenologies and their influence factors at the river level. In this study, we developed a practical method to identify river ice phenologies by leveraging Landsat observations from 2000 to 2021, and established a comprehensive dataset encompassing 7970 river segments across the entire Northern Hemisphere. Our results revealed that the mean freeze-up date, break-up date, and ice duration for these river segments were October 24, May 4, and 192.1 days, respectively. Notably, 56% of the river segments exhibited a warming trend, with the average freeze-up date delayed by 2.7 days per decade, break-up date advanced by 2.5 days per decade, and ice duration shortened by 5.5 days per decade—nearly five times the documented decrease rate over the past 150 years. Furthermore, high-latitude polar regions and the Qinghai-Tibet Plateau demonstrated the most pronounced decreases in ice duration, exceeding 7.0 days per decade on average. We observed a substantial relative contribution, reaching up to 70%, of surface air temperature (SAT) in middle and low latitude regions characterized by relatively high winter temperatures. However, as winter temperatures decrease, the relative influence of SAT diminishes, while the contributions of precipitation, solar radiation, and residuals increase. Our dataset provided essential baseline for further understanding the fundamental physical processes within river systems, offering crucial insights for river management, hydrological disaster risk control, climate change research, and ecosystem conservation efforts. • Developed method using 2.49 M Landsat images for detailed river ice dataset • Tracked patterns and trends in rivers across the Northern Hemisphere • Quantified meteorological factors' contributions to multi-year ice phenologies [ABSTRACT FROM AUTHOR]

• A novel passive cavitation imaging (PCI) scheme was proposed to tackle two practical problems in monitoring high intensity focused ultrasound (HIFU) treatment. • Firstly, a cavitation detection network (CD-NET) model was introduced for the first time to detect the occurrence of cavitation to avoid false positive visualizations in the PCI procedure. • Secondly, cavitation intensity baseline was derived from experiment data, which can help display the dynamic cavitation activities in a more reliable manner. • The enhanced PCI scheme offer an effective method for monitoring HIFU therapies involving cavitation. Passive cavitation imaging (PCI) is an effective technique for monitoring high intensity focused ultrasound (HIFU) procedure due to the correlation between cavitation activities and the therapeutic effects. Nevertheless, current PCI techniques are unable to recognize noise signals from non-cavitation situations, and they fail to accurately visualize the highly dynamic cavitation activities due to the lack of a stable baseline reference. In this study, a deep learning-based cavitation detection network (CD-NET) was proposed to determine whether passively received channel signals originated from cavitation activities or were merely noises. Additionally, a cavitation intensity baseline was derived to better display the drastically time-varying cavitation activities. The CD-NET model was trained and validated with data collected from in-vitro and ex-vivo HIFU sonication experiments, and then tested by in-vivo rabbit experiments. Both CD-NET models, trained with data from the in-vitro agar phantoms and ex-vivo bovine liver tissues, successfully distinguished between cavitation and non-cavitation activities from the same study object, achieving accuracies as high as 99.7% and 99.5%, respectively. In addition, the models trained on in-vitro and ex-vivo datasets achieved accuracies of 88.1% and 91.4%, respectively, when detecting cavitation events from unseen in-vivo data. The results demonstrate that the improved PCI scheme, utilizing the CD-NET model and a data-derived cavitation baseline, is resistant to noise from non-cavitation situations and can depict the dynamic characteristics of cavitation more reliably. In conclusion, this study addressed two practical challenges in PCI techniques, allowing for better monitoring of cavitation-related HIFU sonication in clinical applications. [ABSTRACT FROM AUTHOR]

To optimize the investment scheme of a port in a multiport region, it is necessary to analyze users' port choice habits and the feedback relationship between users' use experience and their port choice behaviors. This paper proposes a method to analyze the process of dynamic change in users' port choices after a specific port invests to enhance its competitiveness; the paper then establishes an analytical model to measure the evolution of port market share. The case study shows that users cannot fully perceive a utility increment at a port when their loyalties are at a lower level, but their loyalty may increase as they experience satisfaction with the port's services, and ultimately, they will fully perceive the objective utility of the port. This means that users' perceived subjective utility lags behind the port's objective utility; thus, a small and undeveloped port should not invest to its maximum capacity when users' loyalties are low but should reduce the port tariff so that users experience the improved service and then invest step by step to effectively give full play to the investment. • Choice habits of port users are analyzed. • The feedback relationship between users' experience and port choice behaviors is integrated in the choice utility function. • Efficiencies of port investment are estimate based on their market competitiveness. • M ethod to analyze the process of dynamic change in users' port choices is given. • It is found that users' perceived subjective utility lags behind objective utility. [ABSTRACT FROM AUTHOR]

Enclosure fisheries have accommodated the widespread expansion of aquaculture in many lakes throughout the Yangtze Plain (YP), China, for over four decades. Such practices have increased food provision but have also triggered various detrimental environmental consequences. To restore ecosystem functions, the Chinese government recently implemented specific regulations to remove enclosure fences from lakes throughout the YP. However, little information is available on the spatial and temporal distributions of the enclosure fences, particularly in relation to the enforcement of recent policy changes. Using synthetic aperture radar (SAR) satellite images taken between 2002 and 2018, we conducted the first comprehensive assessment of the interannual changes in enclosure fences in 17 large lakes throughout the YP. Consistent decreases in fence density were found in most lakes after 2015; 15 lakes had >50% of their fences removed, while 9 lakes had >90% removed. The timing and implementation of the development and destruction of enclosure fisheries were related to government policy; before 2015, regional dynamics in enclosure fisheries were attributed to provincial policies, whereas the nearly ubiquitous fence demolition after 2015 was likely a response to national policy. This study represents remotely sensed evidence that demonstrates the importance of both local and national environmental policies and their effectiveness in mitigating ongoing human impacts on vulnerable and valuable natural resources. These findings provide valuable baseline information for future lake environmental monitoring and restoration in the YP region, and the methods used here could be applied to other lacustrine and coastal regions experiencing similar aquaculture activities. Unlabelled Image • SAR imagery makes it possible to study enclosure fisheries in the Yangtze Plain. • First comprehensive study of the enclosure fisheries for 17 large lakes in the YP • Consistent decreases in the fence density were found after 2015 for most lakes. • Similar provincial dynamics before 2015 were due to local environmental policies. • Consistent demolition after 2015 appeared to be a response to national policy. [ABSTRACT FROM AUTHOR]

In the treatment of uterine fibroids with ultrasound-guided high-intensity focused ultrasound (HIFU), water balloons are considered to be a valuable aid for improving safety and efficiency. However, the water balloons worsen the pathway for acoustic transmission, causing degraded performance both in ultrasound therapy and in ultrasound imaging. This study was aimed at establishing a protocol to evaluate the effects of the water balloon. Simulations and experiments were carefully conducted to quantitatively investigate the effects of water ballons on the efficiency of HIFU energy delivery and on the quality of ultrasound guiding images. More specifically, HIFU-induced temperature increases in the focal region, together with spatial resolution, contrast and signal-to-noise ratio in the ultrasound guiding images, were compared under the conditions with and without the water balloon. Experiment results revealed that the use of water balloons led to decreases in temperature up to 10ºC within the focal region in some specific situations, but the quality of the guiding images was relatively less affected. The study provided knowledge on what influence the water balloon could have in ultrasound-guided HIFU treatment; it also established a practical and standardized evaluation scheme for further optimizing the water balloon, for example, its material and internal liquid compositions. This study can potentially help improve the efficiency and safety of treating uterine fibroids with ultrasound-guided HIFU systems. [ABSTRACT FROM AUTHOR]

Temporal monitoring of inland water bodies using remote sensing images is often impeded by missing data caused by clouds and other adverse conditions. To date, various data recovery algorithms have been developed based on the water occurrence threshold (WOT), where the contaminated pixels are recovered by using long-term historical water distribution information. Here, we propose an improved algorithm, enhanced WOT (EWOT), which addresses the issue of mismatch between the water occurrence product and the actual historical water presence that has been neglected by previous WOT algorithms. The EWOT algorithm achieved an overall high accuracy (with a mean absolute percentage error (MAPE) = 5.1%) and prevailed against a representative WOT algorithm. The accuracy could be further reduced (MAPE = 1.6%) after the application of a novel quality control process. In addition, the temporal coverage of the high-quality surface water area time series was improved by an average of 26.2%, and the percent count and percent area of lakes with high-quality reconstructed data reached as high as 84.5% and 94.7%, respectively, facilitating the utilization of these data in further time series analysis. In general, the improvement was closely associated with the extent of the contamination before recovery. We evaluated the algorithm's ability to be implemented on a large scale in China, and the results generally were in line with previous studies. Nonetheless, our high-quality annual-based dataset presented a more comprehensive and continuous representation of the changes in lake area spanning from 2000 to 2019. The significance of improving the existing WOT algorithms is highlighted in this study, and the proposed method can be readily extended to lakes worldwide, thus providing a valuable data source to examine the causes and possible impacts of lake dynamics. • A novel improvement towards current WOT-based reconstruction algorithms. • A robust quality control process by utilizing two effective quality indicators. • A significant improvement for the overall quality of the lake area time series. • An annual lake area dataset for 4936 natural lakes and 2237 reservoirs in China. • A substantial yet diverse lake area changes between 2000 and 2019 in China. [ABSTRACT FROM AUTHOR]

Abstract Various aspects of the water qualities of the large lakes in the Yangtze Plain (YP) have been studied, while the efforts have been spent on one of the most important parameters -water transparency were only limited to several large lakes. Using in situ remote sensing reflectance and Secchi-disk depth (Z sd) datasets, we assessed the performance of a semi-analytical model recently proposed by Lee et al. (2015) for remote sensing of the Z sd (Z sd, Lee). The results show that a linear scaling correction over Z sd, Lee (Z′ sd, Lee) could lead to improved agreement between remote sensing estimates and field measurements (root mean square error < 35%) in the study region. The Z′ sd, Lee scheme was then applied to MODIS/Aqua observations between 2003 and 2016 to obtain the spatial and temporal dynamics of water transparency in 50 large lakes in the YP. The long-term mean Z sd of the entire region was 0.39 ± 1.17 m during the observation period, with high and low values occurring in warm and cold seasons, respectively. Of the 50 examined lakes, half demonstrated decreasing or increasing Z sd trends, and the number of lakes exhibiting significantly decreasing trends also comparable to the number exhibiting increasing trends. The relative contributions of the seven potential driving factors (from both human activities and natural processes) to the interannual changes in water clarity were quantified for each lake using a multiple general linear model regression analysis. The responses of Z sd to these drivers showed considerable differences among lakes, and human activities demonstrated significant roles in more lakes than those affected by natural variability, accounting for 50% (25/50) and 20% (10/50) of the lakes, respectively. This study provides the first comprehensive basin-scale estimate of the water transparency in the lakes in the YP, and the Z sd results and analysis of driving forces can provide important information for local water quality conservation and restoration. Highlights • Validations of the Lee et al. water clarity algorithm in the Yangtze Plain Lakes • Dynamics of water clarity in 50 large lakes in the YP between 2003 and 2016 • Quantified the contributions of seven factors driving the interannual changes • Human activities significantly influenced more lakes than natural processes. [ABSTRACT FROM AUTHOR]