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This study proposes high-frequency container port congestion measures based on Automatic Identification System (AIS) data. Vessel movement information of 3,957 container ships from March 2017 to April 2017 is included. The world top 20 container ports' berth and anchorage areas are identified through Density Based Spatial Clustering of Applications with Noise (DBSCAN) and convex hull methods, and their hourly port congestion statuses are depicted in terms of the traffic volume and turnaround time. The constructed congestion measures overcome the disadvantages of the traditionally used port or industry data, which is heterogenous, behind the time and not easy to obtain publicly. The higher frequency (hourly) of the proposed measures can effectively monitor any slight change in port performance. A Long Short-Term Memory (LSTM) neural network model is then proposed for congestion prediction using constructed congestion measures. Point prediction and sequence prediction are both performed. We innovatively introduce congestion propagation effects into the prediction model as input features. Using Shanghai, Singapore and Ningbo ports as case studies, results show that the inclusion of congestion propagation effect can improve the prediction performance especially for sequence prediction. This study provides significant implications and decision support for container shipping market participants. [ABSTRACT FROM AUTHOR]

Microgrids allow energy exchange among multiple interconnected microgrids for greater energy efficiency and collective economic interest. However, in some cases, the benefit of some microgrids within the network may not be uncertain. In view of the increasing development of electric vehicles (EVs), a multiobjective model is proposed to improve the performance of microgrids by integrating electric vehicles-to-grid (V2G) and vehicles-to-building (V2B) based on global and individual benefit balance. Two reference models are built to verify the validity of the proposed method, and models are formulated as mixed integer linear programming formats solved by the weighting method. A set of parameters of microgrids are adopted to model the driver behaviors (e.g., available hours of EV), energy transactions (e.g., electricity), performance factor (e.g., emission factor), distributed energy (e.g., solar panel), and energy load of five commercial buildings (e.g., hotel) located in Shanghai. Simulation results demonstrate the effectiveness of the operation decision models in the energy management of microgrids under neutral, proeconomic, proenvironmental, and proenergy weighting scenarios. The case study results specify that the proposed method can achieve operational cost, CO2 emission, and primary energy consumption reductions for each microgrid, with total benefits declining slightly. [ABSTRACT FROM AUTHOR]

• The denitrification rate of urban river sediment feature temporal, spatial and vertical variation. • Urbanization aggravated river pollution, but the denitrification of river sediment can be enhanced. • Denitrification of urban river sediment can remove nearly 20% of the input nitrogen load. Streams and rivers, especially in urban areas, are substantial sinks of bioavailable nitrogen owing to their hydrological connections with terrestrial systems and the intensity of inputs mediated by human activities. Denitrification can account for nitrogen removal in rivers, but its importance in urban rivers has been scarcely studied. This study chose 8 representative rivers in Shanghai, under different level of urbanization, and measured denitrification rates of sediments across a year. The results showed significant differences in temporal, spatial and vertical distributions (p < 0.05). Seasonally, the denitrification rate in spring and winter were lower than in autumn. Spatially, the higher denitrification rate of rivers in residential and industrial areas than that in suburban rivers, which dominated with cultivated land, was weakly related to dissolved oxygen (DO) (p < 0.05, r = −0.380) and ammonium nitrogen (NH 4 +-N) concentration (p < 0.05, r = 0.303) in the water column. Vertically, the surface layer (0–2 cm) accounted for 78.2% of the total denitrification capacity (0–5 cm). The denitrification rates among different depths positively correlated with the extractable nitrate concentration (SNO 3 −-N), the extractable ammonium nitrogen concentration (SNH 4 +-N), the organic carbon concentration (SOC), water content and pH of sediment to varying degrees. In addition, the mean annual denitrification rate of studied rivers was calculated as 2.62 ± 0.420 mg N m−2 h−1, and denitrification contributed nearly 20% of the nitrogen removal, these results underscore the importance of denitrification in nitrogen reduction of urban rivers. [ABSTRACT FROM AUTHOR]

The objective of this study is to propose a methodology for assessing waterway traffic capacity in the Shanghai estuary of the Yangtze River. To achieve this objective, we first put forward the estimation method which utilises the minimum collision distance taking the dynamic ship domain into consideration. Considering possible effects caused by unknown external factors, the waterway traffic capacity is then represented by a probability distribution. Finally, we quantify the equivalent units of ships with various ship sizes as well as the effects of large-sized ships on the waterway traffic capacity. Results show that a large-sized ship is equivalent to more small-sized ships during the daytime period than at night. In addition, the deployment of large-sized ships could increase the waterway traffic capacity and such an increment highly depends on the increased proportion of large-sized ships in the waterway traffic. [ABSTRACT FROM AUTHOR]

Purpose: To compare visual outcomes and aberration outcomes in small incision lenticule extraction (SMILE) versus femtosecond laser LASIK (FS‐LASIK). Methods: This prospective, comparative, nonrandomized clinical study included 68 eyes of 37 patients receiving SMILE and 55 eyes of 30 patients receiving FS‐LASIK between December 2011 and January 2013 at the Fudan University Eye and ENT Hospital (Shanghai, People's Republic of China). Patients were followed up at 3, 6 months and 5 years after surgery. Main outcome measurements included uncorrected (UDVA) and corrected (CDVA) distance visual acuity, manifest refraction, central corneal thickness (CCT), total corneal refractive power (TCRP) and wavefront aberrations. Results: About 98% (49/50) of treated eyes in the SMILE group and 95% (39/41) in the FS‐LASIK group had a postoperative logMAR UDVA of 0 or better. Spherical equivalent (SE) after 5 years was −0.01 ± 0.35 D in the SMILE group and −0.23 ± 0.41 D in the FS‐LASIK group. A regression of −0.02 ± 0.39 D in the SMILE group and −0.12 ± 0.32 D in the FS‐LASIK group was observed between 6 months and 5 years postoperative time‐points. TCRP increased by 0.39 ± 0.38 D in the SMILE group and 0.45 ± 0.49 D in the FS‐LASIK group between 6‐month and 5‐year time‐points. However, no statistically significant difference was found between the SMILE and FS‐LASIK groups in terms of ∆SE, ∆CCT and ∆TCRP between 6 months and 5 years postoperative time‐points. Conclusion: Myopic regression was observed in terms of TCRP but not in subjective refraction. No statistically significant difference in stability was found between SMILE and FS‐LASIK. [ABSTRACT FROM AUTHOR]