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To solve the optimization problem of tugboat scheduling for assisting ships in entering and exiting ports in uncertain environments, this study investigates the impact of the decisions of tugboat operators and port dispatchers on tugboat scheduling under the scenario of dynamic task arrival and fuzzy tugboat operation time. Considering the features of the shortest distance tugboat principle, the first available tugboat principle, and the principle of fairness in the task volume of each tugboat, the tugboat company aims to minimize the total daily fuel consumption of tugboat operations, maximize the total buffer time of dynamic tasks, and minimize the total completion time as the objective functions. Due to the limitations of port vessel berthing and departure, as well as the allocation standards for piloting or relocating tugboats, the present study proposes a Stackelberg game-based fuzzy model for port tugboat scheduling with the tugboat operator and port dispatcher acting as decision makers at the upper and lower levels, respectively. A seagull optimization algorithm based on priority encoding and genetic operators is designed as a solution approach. CPLEX, genetic algorithm, standard seagull optimization algorithm, and simulated annealing algorithm are used to compare and analyze the solution results for the 45 problem cases generated from the actual data obtained from the Guangzhou Port. The results verify the efficiency of the proposed seagull optimization algorithm based on priority encoding and genetic operators. Furthermore, additional experiments are conducted to evaluate the changes in fairness coefficient, uncertain parameter correlation coefficients, and objective function correlation coefficients to demonstrate the practicality of the fuzzy programming model. This analysis involves adjusting the confidence level incrementally from 0 to 100% with respect to the model's uncertain parameters.
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Amidst the intensifying impact of climate change, the extension of navigable periods along Arctic Shipping Routes (ASRs) has garnered attention as a maritime route for container vessels. The urgency to comprehend the reverberations of ASRs on the global container shipping network (GCSN) led to the development of the Latitudinal Centrality Index (LCI), which integrates latitude and centrality in maritime analysis. This index evaluates ASRs' influence across 968 port nodes within the GCSN. By exploring scenarios encompassing seasonal fluctuations over the years, this study delves into the sway of ASRs compared to a benchmark state devoid of ASR engagement. The study's revelations highlight a discovery: the assimilation of ASRs augments interconnectivity, or resilience, within the GCSN. The GCSN thrives as a cohesive and adaptable entity upon full integration of ASRs, indicating a promising trajectory for global container shipping.
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Recycling of used products can provide substantial economic and environmental benefits for supply chain players. However, many factors associated with the design of closed-loop supply chain networks are uncertain in their nature, including demand, opening cost of facilities, capacity of opened facilities, transportation cost, and procurement cost. Therefore, this study proposes a novel fuzzy programming model for closed-loop supply chain network design, which directly relies on the fuzzy ranking method based on a credibility measure. The objective of the presented optimization model aims at minimizing the total cost of the network when selecting the facility locations and transportation routes between the nodes of the network. Based on the problem characteristics, a Migratory Birds Optimization Algorithm with a new product source encoding scheme is developed as a solution approach. The inspiration for the product source coding method originates from the label information of raw material supplier and manufacturing factories on product packaging, as well as the information of each logistics node on the delivery order. This novel encoding method aims to address the limitations of four traditional encoding methods: Prüfer number based encoding, spanning tree based encoding, forest data structure based encoding, and priority based encoding, thereby increasing the likelihood of heuristic algorithms finding the optimal solution. Thirty-five illustrative examples are developed to evaluate the proposed algorithm against the exact optimization method (LINGO) and a Genetic Algorithm, Ant Colony Optimization, Simulated Annealing, which are recognized as well-known metaheuristic algorithms. The results from extensive experiments show that the proposed algorithm is able to provide optimal and good-quality solutions within acceptable computational time even for large-scale numerical examples. The suitability of the model is confirmed through a meticulous sensitivity analysis. This analysis involves adjusting the confidence level incrementally from 50% to 100%, in 5% intervals, with respect to the model's uncertain parameters. Consequently, it yields valuable managerial insights. The outcomes of this research are expected to provide scientific support for related supply chain enterprises and stakeholders.
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Algoritmos , Aves , Lógica Fuzzy , Animais , Migração Animal , Reciclagem/métodos , Modelos TeóricosRESUMO
COVID-19 has had a serious impact on the development of the global shipping industry, especially since the impact on the cruise tourism industry was unprecedented. This study took cruise ships sailing in China ECA, China Exclusive Economic Zone (EEZ), Yangtze River main line, and Xijiang River main line Chinese waters as an example to analyze the key changes in cruise ship emissions during the pandemic. Automatic identification system (AIS) data, vessel static data, and emission control regional data are used to conduct a comprehensive analysis of cruise ship emissions from multiple perspectives such as a port-to-regional comparison. As such, a vessel emission model (i.e., a bottom-up method) is constructed in this research for predicting China ECA and EEZ cruise ship emissions. Compared with 2019, the cruise activities sailing in China's Emission Control Area (ECA) are mainly at berth, and the emissions of cruise ships have dropped significantly, with SOx emissions reduced by 59.11%. In addition, this study also calculates the carbon emissions of China's regional cruises, supplementing China's cruise carbon pool. The research results suggest that cruise operators may improve fuel efficiency, decrease vessel speed, improve routing and scheduling, and enhance fleet management in order to further mitigate the negative effects of the cruise tourism industry on the marine environment.
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Maritime Autonomous Surface Ships (MASS) have received increasing attention from industrial practitioners, researchers, and policymakers because of industry 4.0 and the digitization of the maritime industry. Crucial questions related to security, safety of personnel and vessels, and socio-economic domains have been addressed to a certain extent. In recent years, China has arisen as one of the leading maritime players worldwide, and unmanned vessels could remarkably influence the Chinese maritime industry. However, there is still a lack of systematic studies aiming to develop a deep understanding of potential advantages and challenges associated with the deployment of unmanned vessels in China. Therefore, using a mixed-method research design, this study attempts to obtain valuable insights based on the viewpoints of the key Chinese stakeholders concerning unmanned vessels, including the benefits, the restrictions, the obstacles to large-scale implementation, the risks, and how to mitigate possible implementation barriers. The main advantage of deploying unmanned ships was found to be the reduction in the ship crew size or complete elimination of the ship crew, which would reduce the operating costs and eliminate human errors on board the ships. Nevertheless, along with important advantages, a number of challenges associated with the development and deployment of unmanned ships were identified, including technological challenges, regulatory challenges, safety and security challenges, and technology investment challenges. All these challenges have to be adequately addressed by the relevant stakeholders to ensure the successful deployment of unmanned ships around the globe in the following years.
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COVID-19 is recognized as an infectious disease generated by serious acute respiratory syndrome coronavirus 2. COVID-19 has rapidly spread all over the world within a short time period. Due to the coronavirus pandemic transmitting quickly worldwide, the impact on global healthcare systems and healthcare supply chain management has been profound. The COVID-19 outbreak has seriously influenced the routine and daily operations of healthcare facilities and the entire healthcare supply chain management and has brough about a public health crisis. As making sure the availability of healthcare facilities during COVID-19 is crucial, the debate on how to take resilience actions for sustaining healthcare supply chain management has gained new momentum. Apart from the logistics of handling human remains in some countries, supplies within the communities are urgently needed for emergency response. This study focuses on a comprehensive evaluation of the current practices of healthcare supply chain management in Hong Kong and the United States under COVID-19 settings. A wide range of different aspects associated with healthcare supply chain operations are considered, including the best practices for using respirators, transport of life-saving medical supplies, contingency healthcare strategies, blood distribution, and best practices for using disinfectants, as well as human remains handling and logistics. The outcomes of the conducted research identify the existing healthcare supply chain trends in two major Eastern and Western regions of the world, Hong Kong and the United States, and determine the key challenges and propose some strategies that can improve the effectiveness of healthcare supply chain management under COVID-19 settings. The study highlights how to build resilient healthcare supply chain management preparedness for future emergencies.
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The outbreak of the COVID-19 pandemic has fundamentally shifted learning from the traditional classroom approach to online learning. As such, this study used a revision centre as a case study to develop the factors that contribute to the theoretical framework of online peer learning in the higher education sector due to COVID-19. This study also explores the integrated effects of online peer learning on students and investigates whether advanced information technology creates new opportunities or additional burdens for students in adopting online peer learning environments. Descriptive statistical analysis, factor analysis, and correlation analysis were conducted on survey data gathered from 204 sub-degree students in Hong Kong. The results addressed four main factors developed from 39 variables: enhancement of learning ability, the attitude toward learning, motivation for learning, and interpersonal relationship which were closely associated. The study findings provide strategies and constructive recommendations for educators to develop a new online learning pedagogy, construct sustainable online peer learning, and effectively manage students' online learning to meet the needs for post-COVID online education.
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Tropical cyclones are highly destructive weather systems, especially in coastal areas. Tropical cyclones with maximum sustained winds exceeding 74 mph (≈119 kph) are classified as typhoons in the Northwest Pacific, whilst the term 'hurricanes' applies to other regions. This study aims to investigate the general characteristics of the most devastating and catastrophic tropical cyclones in the USA Europe, and Asia. To achieve the study objectives, the three most devastating typical tropical cyclones in each region were selected. The tropical cyclones were examined based on various features, such as the number of deaths, minimum pressure, highest wind speed, total financial losses, and frequency per year. In contrast to Europe and Asia, the USA has recorded the highest number of catastrophic tropical cyclones. The damage induced by hurricanes Katrina, Harvey, and Maria in the USA totalled approximately USD USD 380 billion. In addition, the present research highlights the demand to improve the public attitude and behaviour toward the impact of climate change along with the enhancement of climate change alleviation strategies. The number of intense tropical cyclones is expected to rise, and the tropical cyclone-related precipitation rate is expected to increase in warmer-climate areas. Stakeholders and industrial practitioners may use the research findings to design resilience and adaptation plans in the face of tropical cyclones, allowing them to assess the effects of climate change on tropical cyclone incidents from an academic humanitarian logistics viewpoint in the forthcoming years.
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Tempestades Ciclônicas , Ásia , Mudança Climática , Estados Unidos , Tempo (Meteorologia) , VentoRESUMO
The COVID-19 pandemic has brought a tremendous impact on the pedagogy and learning experience of students in sub-degree education sector of Hong Kong. Online learning has become the "sole" solution to deal with student learning challenges during this chaotic period. In this study, we explore online learning for sub-degree students by using a community of inquiry (CoI). As such, confirmatory factor analysis (CFA) was conducted on survey data gathered from 287 sub-degree students from the business and engineering disciplines. Results indicated that the network speed for online education determines the perceived cognitive presence, social presence, and teaching presence of students, whereas gender and academic disciplines of students are not moderating factors that create a significant difference in perceived cognitive presence, social presence, and teaching presence of students. Our study findings for creating and sustaining a purposeful online learning community are highlighted.
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After around four decades of fast growth, the cruise industry has become the most profitable and dynamic segment in the entire global leisure and tourism sector. Behind this growth is a significant shift in the profile of cruise consumers/passengers/tourists, with growth rates twice as fast as those of other types of tourists. China has become a strategic emerging market for the global cruise industry, quickly developing their cruise reception business and holding about 10% of the market share of global cruisers. In this paper, we examine and categorize various travel motivations of Chinese cruise tourists by means of a questionnaire via factor analysis, mean analysis, and K-cluster analysis. The results of the study indicate that Chinese cruise tourists are primarily encouraged to participate in cruise tourism by the motivational dimensions of family leisure/relaxation, natural and cultural exploration, bond/communication, social respect, tourism shopping, and cruise-promotion information sources. The strongest motivations for Chinese cruise tourists were found to be family leisure/relaxation and natural/cultural exploration. We identify four types of cruisers using the K-means cluster method. We find that for all cruiser demographics, leisure/relaxation is the most important motivational factor. Based on these results, we propose some specific solutions for expanding the customer pool in the Chinese cruise market.
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Amid the coronavirus outbreak, many countries are facing a dramatic situation in terms of the global economy and human social activities, including education. The shutdown of schools is affecting many students around the world, with face-to-face classes suspended. Many countries facing the disastrous situation imposed class suspension at an early stage of the coronavirus outbreak, and Asia was one of the earliest regions to implement live online learning. Despite previous research on online teaching and learning, students' readiness to participate in the real-time online learning implemented during the coronavirus outbreak is not yet well understood. This study explored several key factors in the research framework related to learning motivation, learning readiness and student's self-efficacy in participating in live online learning during the coronavirus outbreak, taking into account gender differences and differences among sub-degree (SD), undergraduate (UG) and postgraduate (PG) students. Technology readiness was used instead of conventional online/internet self-efficacy to determine students' live online learning readiness. The hypothetical model was validated using confirmatory factor analysis (CFA). The results revealed no statistically significant differences between males and females. On the other hand, the mean scores for PG students were higher than for UG and SD students based on the post hoc test. We argue that during the coronavirus outbreak, gender differences were reduced because students are forced to learn more initiatively. We also suggest that students studying at a higher education degree level may have higher expectations of their academic achievement and were significantly different in their online learning readiness. This study has important implications for educators in implementing live online learning, particularly for the design of teaching contexts for students from different educational levels. More virtual activities should be considered to enhance the motivation for students undertaking lower-level degrees, and encouragement of student-to-student interactions can be considered.
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This data article describes the dataset of the International COVID-19 Impact on Parental Engagement Study (ICIPES). ICIPES is a collaborative effort of more than 20 institutions to investigate the ways in which, parents and caregivers built capacity engaged with children's learning during the period of social distancing arising from global COVID-19 pandemic. A series of data were collected using an online survey conducted in 23 countries and had a total sample of 4,658 parents/caregivers. The description of the data contained in this article is divided into two main parts. The first part is a descriptive analysis of all the items included in the survey and was performed using tables and figures. The second part refers to the construction of scales. Three scales were constructed and included in the dataset: 'parental acceptance and confidence in the use of technology', 'parental engagement in children's learning' and 'socioeconomic status'. The scales were created using Confirmatory Factor Analysis (CFA) and Multi-Group Confirmatory Analysis (MG-CFA) and were adopted to evaluate their cross-cultural comparability (i.e., measurement invariance) across countries and within sub-groups. This dataset will be relevant for researchers in different fields, particularly for those interested in international comparative education.
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In Hong Kong, transfer students encounter different challenges unfolding in their transition from community college to university study. However, limited research has been conducted to explore their discipline-specific challenges. To address this gap, in this study three engineering and science faculties were selected from which to collect data through 35 in-depth interviews with transfer students, followed by a thorough thematic analysis. With the concept of in-betweenness, three main themes were identified: (1) "shifted the focus of study" (three sub-themes: (i) academic excellence in community college; (ii) future career in the university; and (iii) university life); (2) "encountered challenges in the transition" (four sub-themes: (i) non-matching program articulation; (ii) heavy study workload and its associated consequences; and (iii) non-specific administration arrangement and support from university); and (3) "students' voices to enhance learning experiences" (four sub-themes: (i) modify the study duration; (ii) improve program articulation; (iii) improve social adjustment; and (iv) overseas exchange). The results of this study indicate the challenges faced by transfer students in their transition from community college to university and have implications for universities to design and implement appropriate strategies to prepare for the future.