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Addressing the challenges related to urban water bodies is essential for advancing urban planning and development. Therefore, obtaining precise and timely information regarding urban water bodies is of paramount importance. To address issues such as incomplete extraction boundaries, mistaken feature identification, and omission of small water bodies, this study utilized very high-resolution (VHR) satellite images of the Chengdu urban area and its surroundings to create the Chengdu Urban Water Bodies Semantic Segmentation Dataset (CDUWD). Based on the shape characteristics of water bodies, these images were processed through annotation, cropping, and other operations. We introduced Ad-SegFormer, an enhanced model based on SegFormer, which integrates a densely connected atrous spatial pyramid pooling module (DenseASPP) and progressive feature pyramid network (AFPN) to better handle the multi-scale characteristics of urban water bodies. The experimental results demonstrate the effectiveness of combining the CDUWD dataset with the Ad-SegFormer model for large-scale urban water body extraction, achieving accuracy rates exceeding 96%. This study demonstrates the effectiveness of Ad-SegFormer in improving water body extraction and provides a valuable reference for extracting large-scale urban water body information using VHR images. [ABSTRACT FROM AUTHOR]

This paper investigates the inland container transportation problem with a focus on multi-size containers, fuel consumption, and carbon emissions. To reflect a more realistic situation, the depot's initial inventory of empty containers is also taken into consideration. To linearly model the constraints imposed by the multiple container sizes and the limited number of empty containers, a novel graphical representation is presented for the problem. Based on the graphical representation, a mixed-integer programming model is presented to minimize the total transportation cost, which includes fixed, fuel, and carbon emission costs. To efficiently solve the model, a tailored branch-and-price algorithm is designed, which is enhanced by improvement schemes including a heuristic label-setting algorithm, decremental state-space relaxation, and the introduction of a high-quality upper bound. Results from a series of computational experiments on randomly generated instances demonstrate that (1) the proposed branch-and-price algorithm demonstrates a superior performance compared to the tabu search algorithm and the genetic algorithm; (2) each additional empty container in the depot reduces the total transportation cost by less than 1%, with a diminishing marginal effect; (3) the rational configuration of different types of trucks improves scheduling flexibility and reduces fuel and carbon emission costs as well as the overall transportation cost; and (4) extending customer time windows also contributes to lower the total transportation cost. These findings not only deepen the theoretical understanding of inland container transportation optimization but also provide valuable insights for logistics companies and policymakers to improve efficiency and implement more sustainable operational practices. Additionally, our research paves the way for future investigations into the integration of dynamic factors and emerging technologies in this field. [ABSTRACT FROM AUTHOR]

The hole edge of a metal structure is the most likely crack position in an aircraft structure. The quantitative monitoring of a hole-edge crack is important for structural health monitoring. Therefore, this paper presented a grating thin-film sensor based on the potentiometric method. Firstly, the anodic oxidation process was used to prepare thin film on 2A12-T4 aluminum alloy matrix to prevent the aluminum alloy matrix from interfering with the monitoring signal of the sensor. Then the DC superimposed pulsed bias arc ion plating technique was used to prepare the grating thin-film sensor on the surface of the specimen. The output characteristics of the grating thin-film sensor are obtained with its finite element model, and the factors affecting the sensitivity of the sensor are analyzed. Finally, the fatigue crack monitoring tests were carried out to verify the quantitative monitoring capability of the grating thin film sensor. The experimental results show that it is feasible for the grating thin-film sensor to quantitatively monitor the fatigue crack at the hole edge of an aircraft metal structure.

TiO2 has many advantages, such as UV resistance, thermal stability, and antibacterial; the attention toward TiO2 composite materials (TCMs) is rapidly increasing in the protection of stone culture relics. An innovative rod-shaped TCM was synthesized in this study. The structure and morphology of TCM were studied by X-ray diffraction and scanning electron microscopy. The acid resistance, weather resistance, hydrophilicity, and photocatalytic performance of TCM had been investigated. The experimental results indicated that TCM has good protection effects. The stone sample treated with TCM has stronger acid resistance and weather resistance, better hydrophilicity, and more excellent photocatalytic activity compared with the untreated stone. More importantly, the stone treated with TCM has better acid resistance and weather resistance than that treated with normal shaped TiO2 materials of the previous study. This work describes an effective way to protect stone cultural relics.

Aeronautical composite stiffened panels are widely used in aeronautical structure design because of their good mechanical properties. In this paper，the compressive buckling and post-buckling mechanical properties of aeronautical composite stiffened panels were studied. Firstly，the compressive stability of composite stiffened panels was calculated by engineering method，and the predictions of the buckling and failure loads of stiffened panels were obtained；Secondly，the compression stability experiment of the composite stiffened plate is carried out，and the buckling and failure modes，the load-strain and load displacement relationship of the experimental piece，and the buckling and failure loads of the experimental piece are obtained. The results show that the calculated results by engineering method are in good agreement with the test results，and the error of buckling load and failure load are 6.12% and 9.31% respectively. The reasonable application of engineering method can provide better guidance for the experiment；The failure modes of stiffened panels are the delamination of the panels，the bulging and tearing of the skin，the fracture of the stiffeners and the debonding of the stiffeners-panels. The buckling ratio of composite stiffened plates is 1.65，the composite stiffened plates have strong post-buckling bearing capacity；The post-buckling bearing capacity of stiffened plates can be fully applied in engineering to improve the utilization efficiency of structures.

Inflammatory bowel disease (IBD) and atherosclerosis (AS) are both common chronic inflammatory diseases with similar pathophysiological mechanisms. Some studies have shown that IBD patients are at increased risk for early atherosclerosis, myocardial infarction and venous thrombosis. Here we set up a hybrid mouse model associated with atherosclerosis and acute colitis in order to investigate the interplay of the two diseases. We fed ApoE-/- mice with high fat diet to establish atherosclerosis model, and used animal ultrasound machine to detect the artery of mice noninvasively. Then a new hybrid model of atherosclerosis and acute colitis was prepared by drinking water for 7 days. At the end of the experiment, the hybrid model mice showed typically pathological and intuitionistic changes of atherosclerosis and acute colitis. We found the shortened colon length, high histopathological scores of the colon with mucosal erosion and necrosis, hyperlipidemia, a plaque—covered mouse aorta and plaque with foam cells and lipid deposition in the hybrid model group, which proved that the hybrid model was successfully established. At the same time, ultrasonic detection showed that the end-diastolic blood flow velocity and the relative dilation value were decreased, while systolic time / diastolic time, the wall thickness, systolic diameters as well as diastolic diameters were gradually increased, and statistical significance appeared as early as 8 weeks. We clearly described the process of establishing a hybrid model of atherosclerosis and acute colitis, which might provide a repeatable platform for the interaction mechanism exploring and drug screening of atherosclerosis and inflammatory bowel disease in preclinical study. [ABSTRACT FROM AUTHOR]

This paper addresses the drop-and-pickup container drayage problem with empty container constraints. In this problem, a truck is allowed to drop off the container at the customer and then leave. After the container has been packed/unpacked, the truck returns to pick it up. The problem is further complicated by the fact that empty containers at the depot are often limited in number. This container drayage problem is of great practical importance but seldom investigated. In this paper, we first formulate the problem as a directed graph and then mathematically model it as a mixed-integer linear program (MILP) with the objective of minimizing total travel costs. To solve the MILP effectively, we devise a branch and price algorithm that incorporates several performance enhancement strategies, including three versions of the bi-directional label setting algorithm, preprocessing of time windows and a heuristic for high-quality upper bounds. The experimental results indicate that (1) the proposed algorithm significantly outperforms CPLEX in terms of efficiency and effectiveness, (2) an average cost saving of 9.95∼12.25% can be achieved from the drop-and-pickup mode and (3) the benefit of drop-and-pickup mode increases when the customer density and the fixed cost increase. [ABSTRACT FROM AUTHOR]

Confronting the challenges provided by jumbo container vessels, managers of world-class seaports must take into consideration water depths-related constraints when making the vessel berthing decisions. That is, when the water depths satisfy the requirement of jumbo vessels' drafts, these vessels are allowed to sail through the navigation channel. In this paper, we study a tactical berth allocation problem under the consideration of time-varying water depths. For the resolution, we propose an integer programming model, a set partitioning formulation and an improved differential evolutionary algorithm. Computational experiments demonstrate that the set partitioning formulation outperforms the integer programming model and can be applied to solve small- and medium-sized problems. The improved differential evolutionary algorithm is recommended for large-sized problems. [ABSTRACT FROM AUTHOR]

The effect of additional ultrasonic treatment (AUT) on grain refinement and distribution of the SiC particles in brazing seam at different temperatures during the solidification process of brazed joints was investigated, and the mechanism model was constructed. The reason for the microstructural changes induced by AUT was explained. The experimental results indicated that the AUT could effectively refine grain, promote element diffusion, and improve the macroscopic uniformity of SiC particles. Further, the effect of AUT was different at different temperatures. At 480 °C, the power ultrasound promoted the SiC particles migration and grain nucleation. In the semi-solid temperature range, the ultrasonic cavitation played a leading role in help α-Al growing to equiaxed grains. In solid-state, ultrasound only played a role in promoting elements diffusion. When the temperature was 420 °C, the ultrasound effect is best that the average grain size of α-Al is 14.6 μm, the joint's shear strength is 196.5 MPa. [ABSTRACT FROM AUTHOR]