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Optical computing has been proven to have the ability to process information with ultra‐high speed. Here, an all‐optical feature extraction system via sparse representation (AFE‐SR) is introduced. The AFE‐SR, which is achieved by multiple diffractive optical elements (DOEs), can realize the recognition of generated physical fields with the speed of light. The sparse representation simplifies the target and improves the recognition accuracy. With the mathematical analysis principle of sparse optical features extraction and optical integration, the identification accuracy of the generation of physical fields is 100% in 2100 frames of the experimental videos. The application field of optical computing systems is extended to state recognition. [ABSTRACT FROM AUTHOR]

Carbonate‐electrolyte‐based lithium–sulfur (Li–S) batteries with solid‐phase conversion offer promising safety and scalability, but their reversible capacities are limited. In addition, large‐format pouch cells are paving the way for large‐scale production. This study demonstrates the in situ formation of a solid‐electrolyte interphase (SEI) as a protective layer using vinylene carbonate (VC), highlighting its industrial adaptability. A high reversible capacity is achieved by the lithiated poly‐VC SEI formed inside the cathode particles as a nanoscale ionic conduction path, along with the traditional surface protective layer. Furthermore, the severe dissolution of poly‐VC is mitigated by LiF derived from fluorine ethylene carbonate as a co‐solvent, enabling high rate performance and a long cycle life. A large 8 Ah pouch cell is successfully developed, which shows a high energy density of 400 Wh kg−1 based on the cell weight. This work demonstrates the high performance of large‐scale Li–S batteries with the in situ formation of a protective layer as a scalable technique for future applications. [ABSTRACT FROM AUTHOR]

Decoupling of phase and polarization is significant for multidimensional light manipulation. However, this requires traditional cascaded and parallel optical elements, resulting in a bulky and complex system. Metasurfaces can potentially replace complex optical modules as novel ultrathin planar optical elements. Herein, an ultrathin single‐layer metasurface is proposed to decouple the phase and polarization based on the Pancharatnam–Berry phase. The rotation angles of the two nanofins are employed to manipulate the phase and polarization independently, significantly simplifying the design process. Diffraction‐limited focusing with a degree of linear polarization higher than 95% is achieved for wavelengths in the 405–633 nm range. Furthermore, a metasurface can arbitrarily manipulate the relative intensity between different channels. The intensity ratio is adjusted from 0.12 to 6.62. These results will pave the way for miniaturized, integrated, and multi‐channel optical elements. [ABSTRACT FROM AUTHOR]

In public–private partnership (PPP) projects, private sponsors collaborate to manage and implement project tasks through shareholder agreements and subcontracts. It is important to recognize that relying exclusively on contractual arrangements may not guarantee effective collaboration. Additional informal contractual mechanisms, such as trust and reputation, which are embedded in social connections among sponsors, should be considered. However, the existing literature lacks sufficient information on the relationship between social connections and informal contracts. This study employs social network analysis (SNA) and binomial logistic regression analyses to investigate how highway PPP sponsors form ties in dynamic social networks. Specially, it examines four distinct tie-formation mechanisms, including expertise difference, repeated collaboration, preferential attachment, and multiconnectivity. The findings indicate that the sponsor networks exhibited typical characteristics of small-world networks, such as high clustering and short average distance. Moreover, small-world networks showed an evolutionary trajectory characterized by an inverted U-shaped trend. Binomial logistic regression analyses reveal that repeated collaboration and multiconnectivity significantly impact formation of ties between sponsors in both the growth and decline phases. Preferential attachment has limited effects, whereas the impacts of expertise difference vary during growth and decline phases. This study contributes to the current body of knowledge on PPPs by examining the effects of the dynamic network structure of PPP sponsors on their tie formation strategies during different phases. Particularly, these strategies provide new insight into the origins of informal contractual mechanisms. The findings offer valuable evidence for private sponsors in partner selection and strategy development for long-term market viability. Furthermore, these findings provide direction for governmental intervention in regulating PPP markets. [ABSTRACT FROM AUTHOR]

With the global economy's relentless growth and heightened environmental consciousness, sustainable maritime transport emerges as a pivotal development trajectory for the shipping sector. This study systematically analyzes 478 publications searched in the Web of Science Core Collection, from 2000 to 2023, utilizing bibliometric methods to investigate the application areas in sustainable development within the shipping industry. This study begins with an analysis of annual publication trends, which reveals a substantial expansion in research endeavors within this discipline over recent years. Subsequently, a comprehensive statistical evaluation of scholarly journals and a collaborative network assessment are conducted to pinpoint the foremost productive journals, nations, organizations, and individual researchers. Furthermore, a keyword co-occurrence methodology is applied to delineate the core research themes and emerging focal points within this domain, thereby outlining potential research directions for future research. In addition, drawing on the keyword co-occurrence analysis, the advancements in intelligent shipping technologies and green port construction applications within sustainable maritime transport are discussed. Finally, the review discusses the existing challenges and opportunities of sustainable maritime transport from a theoretical and practical perspective. The research shows that, in terms of intelligent shipping technology, data security and multi-source data are the focus that people need to pay attention to in the future; a trajectory prediction for different climates and different ship types is also an area for future research. In terms of green ports, Cold Ironing (CI) is one of the key points of the green port strategy, and how to drive stakeholders to build sustainable green ports efficiently and economically is the future developmental direction. This review serves to enhance researchers' comprehension of the current landscape and progression trajectory of intelligent shipping technologies, thereby fostering the continued advancement and exploration in this vital domain. [ABSTRACT FROM AUTHOR]

We report a discovery that perfunctionalized icosahedral dodecaborate clusters of the type B12(OCH2Ar)12 (Ar = Ph or C6F5) can undergo photo-excitation with visible light, leading to a new class of metal-free photooxidants. Excitation in these species occurs as a result of the charge transfer between low-lying orbitals located on the benzyl substituents and an unoccupied orbital delocalized throughout the boron cluster core. Here we show how these species, photo-excited with a benchtop blue LED source, can exhibit excited-state reduction potentials as high as 3 V and can participate in electron-transfer processes with a broad range of styrene monomers, initiating their polymerization. Initiation is observed in cases of both electron-rich and electron-deficient styrene monomers at cluster loadings as low as 0.005 mol%. Furthermore, photo-excitation of B12(OCH2C6F5)12 in the presence of a less activated olefin such as isobutylene results in the production of highly branched poly(isobutylene). This work introduces a new class of air-stable, metal-free photo-redox reagents capable of mediating chemical transformations.

Axial diffraction-limited multiple foci are a kind of investigated focal field for trapping multiple nano-particles. We first experimentally generated diffraction-limited axial double foci by optimization-free binary planar lens and theoretically demonstrated it, which can be applied in multi-particle trapping. The proposed binary planar lens was analytically designed. The BPL has a numerical aperture of 0.9 and a focal length of 150 μm. The focal field of the binary planar lens, which is composed of diffraction-limited axial double foci, was first experimentally validated. The measured maximum lateral full widths at half maximum of the two generated focal spots were diffraction-limited and consistent with the theoretical. The axial double foci formed two stable optical traps that can trap two Rayleigh dielectric particles simultaneously. The radial, azimuthal and axial optical forces of the double optical traps are in good uniformity, which are 0.98, 0.99 and 0.96, respectively.

The inter-satellite laser ranging interferometer is one of the core components of future gravity missions to achieve high ranging precision. This work builds a preliminary breadboard of the off-axis optical bench design, which integrates the merits of the off-axis optical bench design of GRACE Follow-On mission and other on-axis designs. The study finds that the displacement noise between two optical benches has been reduced to 20 n m / Hz at a frequency of 10 mHz, and the differential wavefront sensing noise has been suppressed to 1 0 − 5 rad / Hz at 1 kHz as well. In addition, the tilt-to-length coupling noise related to the piston effect is restricted within 30 μm/rad, and the relative parallelism error of the transmitting beam and receiving beam is less than 4.5%. The results show that this off-axis optical bench design is an important candidate for China's future gravity missions. [ABSTRACT FROM AUTHOR]

The lift force of a T-foil, which varies with ship motion, can counteract the wave exciting force during wave encounters. The phase difference between the periodic lift force and the wave exciting force significantly impacts the T-foil's effectiveness. This study investigates the phase difference between lift force and motion to optimize the control equation for the T-foil's angle, thereby reducing negative feedback. The T-foil's hydrodynamic performance is first calculated using computational fluid dynamics. Time-domain calculations of the phase lag between lift force and motion under open-loop control in still water are then used to determine the dimensionless phase lag of the T-foil's angle at various frequencies, facilitating further optimization of the control method. Finally, calculations of trimaran heave and pitch in regular waves are conducted. The results demonstrate that, under phase lag control, the T-foil's lift force phase precedes ship motion by approximately 0.2 s, reducing hysteresis in the anti-vertical motion effect. Comparisons of vertical hull motions between different control methods reveal a 20% reduction in vertical motion with phase lag control compared to pitch control. This study concludes that phase lag is a crucial factor in T-foil control optimization. [ABSTRACT FROM AUTHOR]