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The shipping industry, which undertakes over 90% of global trade and transportation, has rich digital scenarios. Empowering the shipping industry through smart port construction and integrating ports with virtual–real integration to form a smart port digital base has become an industry consensus. This study defines the smart ports and the virtual – real integration technology system, and analyzes the demand of port operation for virtual – reality integration technology from five aspects: operation planning, activity implementation, equipment operation and maintenance, safety and emergency response, and energy conservation. It also summarizes maps of six virtual – real integration technologies and their application scenarios in smart ports, the technologies being system simulation, extended reality, information-physical system, digital twin, parallel system, and metaverse. After sorting out the development idea and examining scientific issues, a system framework is proposed for the high-quality development of smart ports driven by virtual–real integration technologies, covering the development positioning of technology systems, key technology development directions, and research directions in key fields. Suggestions for development are proposed from the perspectives of deepening application, policy incentives, technological demonstration, and talent cultivation, thereby providing a reference for the engineering application of the virtual–real integration technology system in smart ports.

The rapid development of the shipping industry has made energy consumption and environmental problems of traditional ships increasingly prominent. Hydrogen-powered ships are one of the development directions for waterway transportation vehicles and will play a significant part in achieving the carbon peak and carbon neutralization goals in the waterway transportation field. Therefore, it is urgent to research the innovative developmental mode of hydrogen-powered ships in China. The development status of hydrogen-powered ships is summarized in this article, and the layout of the hydrogen-powered ship industry is analyzed from the perspectives of industrial chain development trend and coordinated development layout. The technical and economic feasibility of developing hydrogen-powered ships is analyzed from the aspects of hydrogen and ammonia fuel, hydrogen fuel cell, hydrogen internal combustion engine, infrastructure, and total cost of ownership. Moreover, the key links of the industry chain of hydrogenpowered ships are analyzed, including hydrogen production, hydrogen transportation, large-capacity hydrogen storage, safe fueling, fuel cell, hydrogen internal combustion engine, multi-energy collaborative control, and safety in hydrogen application. Based on national conditions, we proposed multi-stage development goals, a development roadmap for hydrogen-powered ships, and a construction path for the hydrogen fuel supply system. To promote the rapid and high-quality development of hydrogen-powered ships, China needs to clarify application scenarios, develop key technologies, improve infrastructure facilities, and innovate operation systems.

Energy is vital for the survival and development of human society. Waterway transportation, as a significant component of the transportation industry, is one of major fields of energy consumption and greenhouse gas emissions. Therefore, the integrated development of waterway transportation and energy becomes a powerful measure against severe challenges such as resource shortage, climate change, and environmental pollution. This paper reviews the current energy consumption characteristics of waterway transportation in China in terms of ships and ports, and evaluates the evolution trend of energy demand of relevant main parts from the perspectives of energy supply, quality, and utilization mode. The technical assessment of the integrated development of waterway transportation and energy is conducted, including natural endowment analysis, energy application potential of infrastructure assets, and research and judgment on energy demand. Based on this, the development principles, ideas, and pathways of water way transportation and energy integration in China are proposed. Moreover, this paper proposes suggestions for promoting the integration of waterway transportation and energy in China from the aspects of policy, key technology, and personnel training, so as to provide a basic reference for cross-disciplinary research and high-quality development of the waterway transportation industry.

Objective: This study aimed to enhance the understanding of the role of estrogen in lymphangioleiomyomatosis(LAM) and to conclude the impact of estrogen-altering events on the condition and recent advances in estrogen-based treatments for LAM. Results: LAM development is strongly linked to mutations in the tuberous sclerosis gene (TSC1/2) and the presence of estrogen. Estrogen plays a significant role in the spread of TSC2-deficient uterine leiomyoma cells to the lungs and the production of pulmonary LAM. Menstruation, pregnancy, estrogen medication, and other events that cause an increase in estrogen levels can trigger the disorder, leading to a sudden worsening of symptoms. Current findings do not support using estrogen-blocking therapy regimens. However, Faslodex, which is an estrogen receptor antagonist, presents new possibilities for future therapeutic approaches in LAM. Conclusion: Estrogen is crucial in the development and spread of LAM. The use of estrogen inhibitors or estrogen receptor antagonists alone does not provide good control of the disease or even poses a greater risk, and the use of a combination of mTOR receptor inhibitors, complete estrogen receptor antagonists, estrogen inhibitors, and autophagy inhibitors targeting important signaling pathways in LAM pathogenesis may be of greater benefit to the patient. [ABSTRACT FROM AUTHOR]

Aiming to reduce motor speed estimation and torque vibration present in the permanent magnet synchronous motors (PMSMs) of rim-driven thrusters (RDTs), a position-sensorless control algorithm using an adaptive second-order sliding mode observer (SMO) based on the super-twisting algorithm (STA) is proposed. In which the sliding mode coefficients can be adaptively tuned. Similarly, an iterative learning control (ILC) algorithm is presented to enhance the robustness of the velocity adjustment loop. By continuously learning and adjusting the difference between the actual speed and given speed of RDT motor through ILC algorithm, online compensation for the q-axis given current of RDT motor is achieved, thereby suppressing periodic speed fluctuations during motor running. Fuzzy neural network (FNN) training can be used to optimize the STA-SMO and ILC parameters of RDT control system, while improving speed tracking accuracy. Finally, simulation and experimental verifications have been conducted on the vector control system based on the conventional PI-STA and modified ILC-STA. The results show that the modified algorithm can effectively suppress the estimated speed and torque ripple of RDT motor, which greatly improves the speed tracking accuracy. [ABSTRACT FROM AUTHOR]

Analysis of thermodynamic parameters' effects on the S-CO2 recompression Brayton cycle for recovering the main engine exhaust gas waste heat of an ocean-going 9000 TEU container ship are carried out first in this paper. NSGA-II algorithm-based multi-objective optimizations are conducted to maximise net power output and exergetic efficiency as well as to minimise the levelized cost of energy (LCOE). The final optimal result from Pareto front solutions is decided by decision-making processes. The results show that the LCOE increases along with the enhancement of net power output and exergetic efficiency, and the maximal objectives always appear near the upper boundary of exhaust gas temperature. The final optimal result decided by TOPSIS decision-making has higher rationality and accuracy than that obtained by the LINMAP method. Regarding the final optimal results of triple-objective and dual-objective optimizations obtained by the TOPSIS method, the former achieved more reasonable results, since its optimal net power output and exergetic efficiency are 1.29% and 5.11% higher than the latter, while its LCOE increased by 2. 28% as a result of the increase of the net power output. The recompression Brayton cycle is better for recovering the exhaust gas waste heat in ships compared with the simple recuperative cycle without recompression. [ABSTRACT FROM AUTHOR]