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Existing research on auto-berthing of ships has mainly focused on the design and implementation of controllers for automatic berthing. For the real automatic docking processes, not only do external environmental perturbations need to be taken into account but also motion paths, docking strategies and ship mechanical constraints, which are important influential factors to measure autonomous docking methods. Through a literature review of ship path planning and motion control for automatic berthing, it is found that many studies ignore the interference of the actual navigational environment, especially for ships sailing at slow speed when berthing, or do not consider the physical constraints of the steering gear and the main engine. In this paper, we propose a hybrid approach for autonomous berthing control systems based on a Linear Quadratic Regulator (LQR) and Covariance Matrix Adaptation Evolution Strategy (CMA-ES), which systematically addresses the problems involved in the berthing process, such as path planning, optimal control, adaptive berthing strategies, dynamic environmental perturbations and physically enforced structural constraints. The berthing control system based on the LQR and modified LQR-CMA-ES have been validated by simulation work. The simulation results show that the proposed method is able to achieve the automatic docking of the ship well and the system is robust and well adapted to environmental disturbances at slow speed when docking. [ABSTRACT FROM AUTHOR]

Ethylene plays a pivotal role in plant stress resistance and 1-aminocyclopropane-1-carboxylic acid synthase (ACS) is the rate-limiting enzyme in ethylene biosynthesis. Upland cotton (Gossypium hirsutum L.) is the most important natural fiber crop, but the function of ACS in response to abiotic stress has rarely been reported in this plant. We identified 18 GaACS, 18 GrACS, and 35 GhACS genes in Gossypiumarboreum, Gossypium raimondii and Gossypiumhirsutum, respectively, that were classified as types I, II, III, or IV. Collinearity analysis showed that the GhACS genes were expanded from diploid cotton by the whole-genome-duplication. Multiple alignments showed that the C-terminals of the GhACS proteins were conserved, whereas the N-terminals of GhACS10 and GhACS12 were different from the N-terminals of AtACS10 and AtACS12, probably diverging during evolution. Most type II ACS genes were hardly expressed, whereas GhACS10/GhACS12 were expressed in many tissues and in response to abiotic stress; for example, they were highly and hardly expressed at the early stages of cold and heat exposure, respectively. The GhACS genes showed different expression profiles in response to cold, heat, drought, and salt stress by quantitative PCR analysis, which indicate the potential roles of them when encountering the various adverse conditions, and provide insights into GhACS functions in cotton's adaptation to abiotic stress. [ABSTRACT FROM AUTHOR]

Based on the phase transition of vanadium dioxide(VO2), an ultra-broadband tunable terahertz metamaterial absorber is proposed. The absorber consists of bilayer VO2 square ring arrays with different sizes, which are completely wrapped in Topas and placed on gold substrate. The simulation results show that the absorption greater than 90% has frequencies ranging from 1.63 THz to 12.39 THz, which provides an absorption frequency bandwidth of 10.76 THz, and a relative bandwidth of 153.5%. By changing the electrical conductivity of VO2, the absorption intensity can be dynamically adjusted between 4.4% and 99.9%. The physical mechanism of complete absorption is elucidated by the impedance matching theory and field distribution. The proposed absorber has demonstrated its properties of polarization insensitivity and wide-angle absorption, and therefore has a variety of application prospects in the terahertz range, such as stealth, modulation, and sensing. [ABSTRACT FROM AUTHOR]

Simple Summary: TCP transcription factors (TF) are indispensable for the normal functioning of plant growth and development. This study identified and performed phylogenetic analysis on 218 TCP genes in four cotton species. We also observed conserved exon-intron structures and protein motif distribution patterns in GhTCP genes. GhTCP62 was enriched in the axillary bud, indicating that it plays a role in branching. GhTCP62 is a nuclear-localized TF, the overexpression of which decreases the number of cauline-leaf branches and rosette-leaf branches in Arabidopsis. Additionally, the expression levels of HB21 and HB40 genes increased in plants with GhTCP62 overexpression, demonstrating that GhTCP62 could regulate branching by regulating HB21 and HB40. Collectively, the GhTCP62 TF located in the nucleus was highly enriched in the axillary buds, and GhTCP62 overexpression lines demonstrated fewer rosette-leaf branches and cauline-leaf branches, indicating that GhTCP62 regulates branching in Arabidopsis. TEOSINTE-BRANCHED1/CYCLOIDEA/PCF (TCP) transcription factors play an essential role in regulating various physiological and biochemical functions during plant growth. However, the function of TCP transcription factors in G. hirsutum has not yet been studied. In this study, we performed genome-wide identification and correlation analysis of the TCP transcription factor family in G. hirsutum. We identified 72 non-redundant GhTCP genes and divided them into seven subfamilies, based on phylogenetic analysis. Most GhTCP genes in the same subfamily displayed similar exon and intron structures and featured highly conserved motif structures in their subfamily. Additionally, the pattern of chromosomal distribution demonstrated that GhTCP genes were unevenly distributed on 24 out of 26 chromosomes, and that fragment replication was the main replication event of GhTCP genes. In TB1 sub-family genes, GhTCP62 was highly expressed in the axillary buds, suggesting that GhTCP62 significantly affected cotton branching. Additionally, subcellular localization results indicated that GhTCP62 is located in the nucleus and possesses typical transcription factor characteristics. The overexpression of GhTCP62 in Arabidopsis resulted in fewer rosette-leaf branches and cauline-leaf branches. Furthermore, the increased expression of HB21 and HB40 genes in Arabidopsis plants overexpressing GhTCP62 suggests that GhTCP62 may regulate branching by positively regulating HB21 and HB40. [ABSTRACT FROM AUTHOR]

This paper uses countries in the South China Sea Region (SCSR) as examples to study the level of regional cooperation in the marine plastic waste cleanup initiative. We designed a cooperation model to investigate the "cleanup system" from the Ocean Cleanup initiative to reduce marine plastic pollution. The non-cooperative game theory was applied to regional cooperation. The simulation results indicate that the plastic waste cleanup cooperation in the SCSR is related to the plastic trade network structure, the influence parameters of the Experience-Weighted Attraction learning model, and the economic effects. The results suggest that regional cooperation in the cleanup system in the SCSR is feasible, and it could create a significantly larger investment in the cleanup project than the current project attracts. Therefore, countries in the SCSR should adjust their laws and policies to make a good cooperative environment and to maximize the contribution to the marine plastic waste cleanup. [ABSTRACT FROM AUTHOR]

In this paper, we reported a theoretical study of a novel Surface plasmon resonance (SPR) biosensor composed of BK7 prism, gold (Au)/silver (Ag) bimetallic layer, silicon and two-dimensional (2D) materials. The bimetallic layer combines the advantages of Au and Ag and the high refractive index silicon layer enhances the electric field on the surface of the sensor, so that the sensor has a better overall performance in terms of sensitivity and figure of merit (FOM). Compared with ordinary dielectrics, 2D materials have excellent photoelectric properties, such as larger specific surface area, higher carrier density and stronger adsorption capacity, which improve the detection ability of the sensor. The sensitivity of the optimized sensor achieves 297.2°/RIU, 274°/RIU and 246°/RIU when the silicon layer is covered with graphene, MXene (Ti3T2Cx) and MoS2, respectively. Compared with the traditional SPR sensor, the sensitivity of the structure has been significantly improved, and its excellent performance has broad application prospects in biosensing and other fields. [ABSTRACT FROM AUTHOR]