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Ray tracing has been regarded as the next generation of mainstream image rendering technology for a long time because of the authenticity of its rendering effect, and it is a hot research point in the field of computer graphics. In recent years, academics and commercials have extensively researched real-time ray tracing. To promote the research of real-time ray tracing, this paper reviews, analyses, and summaries the related literature. Firstly, the concept, algorithms, and classification of acceleration structures are introduced. Three commercial graphics processing units (GPU) supporting ray tracing are introduced and the differences between them are compared. This paper summarizes the optimization of ray tracing from six aspects, ray packet, stackless traversal, ray reorder, wide BVH, denoising techniques, and real-time ray tracing combined with the artificial?neural network, and expounds on the advantages and disadvantages of the relevant specific methods. Based on the acceleration of the algorithms, the hardware acceleration method on GPU and the dedicated architectures are summarized. Finally, this paper makes a brief summary of the content, points out the difficulties that real-time ray tracing is still challenged, and looks forward to the future development direction. It can help researchers systematically understand real-time ray tracing status and provide follow-up research ideas.

The Kuroshio Loop Current (KLC) is an important form of Kuroshio intrusion into the northeastern South China Sea (NESCS), which has significant influences on dynamical and biogeochemical processes in the NESCS. Recent studies suggested that the KLC is a hot spot of submesoscale processes (submesoscales) with spatiotemporal scales of O(1–10) km and O(1–10) days, but submesoscales' roles in energy cascade and salt and heat transports remain obscure. Here, we investigate this issue through analyzing outputs from a 1/48° simulation. The kinetic energy exchange rate between submesoscale and larger‐scale processes (KER) is overall positive in the KLC region, which suggests the dominance of forward cascade. The magnitude of KER is comparable with the temporal change rate of larger‐scale kinetic energy in the upper 200 m. We also find that magnitude and direction of KER are closely associated with strain rate and horizontal divergence of background flows, respectively. In addition, the KLC region shows elevated submesoscale salinity and heat diffusivities with magnitudes reaching O(102) m2 s−1. During the KLC period, horizontal mixing by submesoscales can transport 0.90 × 1013 kg salt and 0.71 × 1020 J heat westward into the NESCS interior, which are an order of magnitude larger than those caused by the mesoscale eddy shedding from the KLC. These results suggest that submesoscales play important roles not only in energy cascade but also in salt and heat transports in the KLC region. Therefore, the roles of submesoscales should be taken into account when studying energy, salt, and heat budgets in the NESCS. Plain Language Summary: As the western boundary current of the North Pacific subtropical gyre, the Kuroshio can intrude into the northeastern South China Sea (NESCS) in the form of Kuroshio Loop Current (KLC), which modulate the tracer and energy budgets of NESCS through shedding eddies. Although previous studies have reported that the KLC region is abundant with submesoscale processes (submesoscales) with spatiotemporal scales of O(1–10) km and O(1–10) days, their roles in cross‐scale energy transfer and salt and heat transports are poorly known. Here, the above issues are examined through an analysis of outputs from a 1/48° ocean simulation. We find that larger‐scale processes generally feed submesoscales through a forward energy transfer in upper 200 m, whose rate is comparable in magnitude with the temporal change rate of larger‐scale kinetic energy. Furthermore, the horizontal mixing effect of submesoscales can transport a huge amount of heat and salt westward into the NESCS interior during the KLC period. The salt and heat transports are an order of magnitude larger than those caused by the mesoscale eddy shedding from the KLC. The above results suggest that submesoscales associated with the KLC play important roles in the energy, heat, and salt budgets in the NESCS. Key Points: Submesoscales in the Kuroshio Loop Current (KLC) are examined using high‐resolution simulation outputsEnergy exchange between submesoscales and KLC plays an important role in the local energy budgetHorizontal salt and heat transports by submesoscales are much larger than those by mesoscale eddy shedding from the KLC [ABSTRACT FROM AUTHOR]

The digital economy, the tourism industry, and ecological protection are closely related, which holds paramount significance for regional sustainable development. Based on panel data from 2011 to 2021 in the Yellow River Basin, the study scrutinizes the spatial and temporal variances and driving factors of the three-system coupling coordination degree. The results indicate that: (1) The development level of the three systems is significantly different. The coupling coordination degree shifts from imminent imbalance to marginal coordination, but there is a noticeable expansion in spatial disparities. (2) The coupling coordination degree of non-resource cities significantly surpasses that of resource cities, and regenerative cities outperform growing, mature, and declining cities. The overall pattern of the provincial capital cities "center-periphery", decreased the coordination characteristics. The spatial correlation of coupling coordination degree presents two aggregation patterns of "high-high" and "low-low", and the overall correlation gradually weakens. (3) The driving factors reveal that the economic driving force is the largest, followed by the internal driving force, and the government regulatory force and scientific and technological driving force are relatively weak. Consequently, this paper proposes to strengthen the integration and penetration function of the digital economy and have it play the linkage role between regions. This lays down a solid foundation for crafting scientifically informed policies aimed at achieving regional sustainable development. [ABSTRACT FROM AUTHOR]

Fourier ptychography (FP) is an enabling imaging technique that produces high‐resolution complex‐valued images with extended field coverages. However, when FP images a phase object with any specific spatial frequency, the captured images contain only constant values, rendering the recovery of the corresponding linear phase ramp impossible. This challenge is not unique to FP but also affects other common microscopy techniques — a rather counterintuitive outcome given their widespread use in phase imaging. The underlying issue originates from the non‐uniform phase transfer characteristic inherent in microscope systems, which impedes the conversion of object wavefields into discernible intensity variations. To address this challenge, spatially‐coded Fourier ptychography (scFP) is presented for true quantitative phase imaging. In scFP, a flexible and detachable coded thin film is attached atop the image sensor in a regular FP setup. The spatial modulation of this thin film ensures a uniform phase response across the entire synthetic bandwidth. It improves reconstruction quality, corrects refractive index underestimation issues prevalent in conventional FP, and adds a new dimension of measurement diversity in spatial domain. The development of scFP is expected to catalyze new research directions and applications for phase imaging, emphasizing the need for true quantitative accuracy with uniform frequency response. [ABSTRACT FROM AUTHOR]