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This paper studies the joint optimization problem of vessel scheduling and refueling strategy for container liner shipping with cooperative agreements signed by the container terminal operators and the shipping company with multiple vessel arrival time windows, multiple start and end times, and multiple handling rates. A non-linear mixed integer programming model for vessel scheduling and refueling strategy problem of liner shipping is established considering fuel price difference and discount factors at different refueling ports, which aims to minimize the total cost of liner shipping service. A set of discretization and linearization technique is applied to the original model in accordance with the vessel navigation controlling practice. Taking the AEX1 route served by China COSCO Shipping Corporation Limited as an example, a large number of simulation verifications are conducted. The results of numerical examples show that the joint optimization of vessel scheduling and refueling strategy helps shipping companies to flexibly adjust vessel sailing speed. It can significantly reduce the total cost of liner shipping service. The sensitivity analysis indicates that the total cost of liner shipping service and the vessel refueling volume in a voyage will reduce with the expansion of time window of vessel arrival at port in the cooperative agreement. No matter how the fuel price changes, the joint optimization of vessel scheduling and refueling strategy can effectively reduce the total cost of liner shipping service.

A stereo vision system provides important support for underwater robots to achieve autonomous navigation, obstacle avoidance, and precise operation in complex underwater environments. This article proposes an unsupervised underwater stereo matching method based on semantic attention. By combining deep learning and semantic information, it fills the challenge of insufficient training data, enhances the intelligence level of underwater robots, and promotes the progress of underwater scientific research and marine resource development. This article proposes an underwater unsupervised stereo matching method based on semantic attention, targeting the missing training supervised dataset for underwater stereo matching. An adaptive double quadtree semantic attention model for the initial estimation of semantic disparity is designed, and an unsupervised AWLED semantic loss function is proposed, which is more robust to noise and textureless regions. Through quantitative and qualitative evaluations in the underwater stereo matching dataset, it was found that D1 all decreased by 0.222, EPE decreased by 2.57, 3px error decreased by 1.53, and the runtime decreased by 7 ms. This article obtained advanced results. [ABSTRACT FROM AUTHOR]

Improving individuals' low-carbon awareness has become an important research topic. Gamification design is regarded as a potential IT solution to this social problem. Although much research is concerned with the effect of low-carbon awareness to improve individuals' behaviour, little attention has been paid to exploring how to improve low-carbon awareness, especially in the context of green gamification. To fill this research gap, our study uses the cognitive dissonance theory to build a theoretical model for exploring the impacts of green gamification factors on individuals' low-carbon awareness. The model is also used to explore the mediating role of cognitive dissonance and the moderating effect of emotional dependence. Empirical results reveal that visibility of achievement, competition, and interactivity have positive impacts on users' cognitive dissonance, which further positively affect users' low-carbon awareness. In addition, users' emotional dependence positively moderates the relationship between green gamification factors and users' cognitive dissonance. These results extend the cognitive dissonance theory and the literature on green gamification. New insights and practical implications for the designers of gamification application and environmental protection organisations are also provided in our study. [ABSTRACT FROM AUTHOR]

In this study, we report that geopolymer materials containing different amounts of graphitic carbon nitride (g‐C3N4) (C3N4/GP) can remove methylene blue (MB) using the synergistic effects of adsorption and photodegradation. A geopolymer containing 3 wt% g‐C3N4 (3 wt%C3N4/GP) had the best MB removal efficiency of 94.62% within 60 min, under visible light. The results showed that geopolymers can act as carriers for g‐C3N4, and the relative amount of adsorbent and photocatalyst influences the removal of MB. 3 wt%C3N4/GP was also used for additive manufacturing by using direct ink writing technology. In order to improve the efficiency of MB removal, a pore‐forming agent (K12) was added in the synthesis process to prepare three‐dimensional‐printed porous C3N4/GP. The results showed that the porous C3N4/GP was effective in removing MB. This work provides a simple strategy for preparing efficient and green materials for removing organic pollutants. [ABSTRACT FROM AUTHOR]

Introduction:The coronavirus disease 2019 (COVID-19) pandemic has created lots of difficulties for individuals to seek medical help offline. Telehealth is considered as a potential approach to solve this issue. During the COVID-19 pandemic, although the use of telehealth has increased in the short term, it still remains unknown whether the use of telehealth can maintain a high level of development in the long term. The purpose of this article is to investigate the impact of COVID-19 pandemic on telehealth use across time and regional medical resources. Materials and Methods:Our research used the Internet search index from Baidu Index Platform in 31 provinces of China as the proxy of telehealth use. A total of 2,119,486 times of searching behaviors from January 2018 to December 2021 are included in our dataset. Changing plots, the method of analysis of variance and empirical models are applied to reveal the relationship between COVID-19 pandemic and telehealth use. Results:Baidu Index counts increased (p < 0.01) at the beginning of COVID-19 pandemic (2020) but started to decline (p < 0.01) during the period of regular epidemic prevention and control (2021). Moreover, the counts of Baidu Index in regions with rich medical resources are higher than those in other regions in 2020. Comparing Baidu Index counts in 2020, the COVID-19 pandemic has higher positive effects on telehealth use during the period of 2021 in regions with average and poor medical resources. Conclusions:COVID-19 pandemic has a positive effect on telehealth use in 2020 but has a negative effect in 2021. During the epidemic, telehealth use differs in regions with rich, average, and poor medical resources. Our findings indicate that the use of telehealth should be promoted with different measures in regions with different medical resources, thereby contributing its healthy development in the long term. [ABSTRACT FROM AUTHOR]

This paper investigates the problem of containership sailing speed and fleet deployment optimization in an intercontinental liner shipping network. Under the consideration of the time value of container cargo, three kinds of impact of sailing speed changes on long legs of each liner route are analysed, and a time-based freight rate strategy is proposed. Then, the optimization problem is formulated as a mixed-integer nonlinear programming. Its goal is to maximize the total profits of a container liner shipping. To find the optimal solution to the model and improve the efficiency of model solution, a discretization algorithm is proposed. Numerical results verify the applicability of the proposed model and the efficiency of the algorithm. In addition, the time-based freight rate strategy is able to achieve more profit compared to a fixed freight rate strategy., 1. Introduction Container liner shipping services play an important role in maritime freight transportation [1]. Its main task is the transportation of containerized cargo (containers) such as manufactured products, food, [...]