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A stable and robust odometry system is essential for autonomous robot navigation. The 4D millimeter-wave radar, known for its resilience in harsh weather conditions, has attracted considerable attention. As the latest generation of FMCW radar, 4D millimeter-wave radar provides point clouds with both position and Doppler velocity information. However, the increased uncertainty and noise in 4D radar point clouds pose challenges that prevent the direct application of LiDAR-based SLAM algorithms. To address this, we propose a SLAM framework that fuses 4D radar data with gyroscope readings using graph optimization techniques. Initially, Doppler velocity is employed to estimate the radar's ego velocity, with dynamic points being removed accordingly. Building on this, we introduce a pre-integration factor that combines ego-velocity and gyroscope data. Additionally, leveraging the stable RCS characteristics of radar, we design a corresponding point selection method based on normal direction and propose a scan-to-submap point cloud registration technique weighted by RCS intensity. Finally, we validate the reliability and localization accuracy of our framework using both our own dataset and the NTU dataset. Experimental results show that the proposed DGRO system outperforms traditional 4D radar odometry methods, especially in environments with slow speeds and fewer dynamic objects. [ABSTRACT FROM AUTHOR]

The carrying-soil effect is an important factor affecting the success or failure of rectangular pipe jacking construction. Because it is difficult to explore the dynamic evolution process of the carrying-soil effect in the field test, this paper relies on the pipe jacking project of a comprehensive pipe gallery in Suzhou City, and uses ABAQUS 2021 finite element software to simulate the jacking process of rectangular pipe jacking. Based on the theory of plastic mechanics of rock and soil and the related research and application status, the equivalent plastic strain index is introduced as the basis for judging the failure boundary of soil in the numerical simulation results, and the boundary between the carrying-soil area and the surrounding soil is determined, that is, the shear fracture surface. According to the principle of plastic potential energy, the development direction of the fracture surface is consistent with the direction of plastic flow, so as to predict the development direction of the boundary of the carrying-soil area. According to the change in the equivalent plastic strain cloud map with the jacking mileage, the evolution process of the carrying-soil effect is clarified, and the dynamic evolution law of the carrying-soil area is revealed, which is of great significance for predicting the disturbance of the surrounding soil during the construction of rectangular pipe jacking and accurately evaluating the environmental effect of the construction. [ABSTRACT FROM AUTHOR]

The Laguerre-Gaussian (LG) and Hermite-Gaussian (HG) modes can be interconverted with an astigmatism phase. In this paper, based on the single beam, the interconversion of LG and HG beams array with the astigmatism phase is analyzed theoretically and the spatial mapping relationship is derived. In the experiment, 1 × 3, 2 × 2, 3 × 3 LG beams arrays are generated and converted into HG beams array via employing a spatial light modulator loaded with 0°, 90°, 45°, −45° astigmatism phases. The experimental results are in great agreement with the theoretical analyses. Moreover, from the number and direction of the dark fringe of converted HG beams array, the orbital angular momentum information of LG beams array can be obtained. This work theoretically perfects the theoretical model of the interconversion between LG and HG beams based on an astigmatism phase, and also provides a theoretical support for measuring the LG beams array.

Parasitism is known to affect the behavior of host species to enhance parasite dispersal and transmission. However, host behavioral responses to parasitism unrelated to parasite dispersal and transmission have been much less studied. The objective of this study was to determine whether grasshopper hosts infected and uninfected with a parasitic fly (Blaesoxipha sp.) differ in terms of the nutrient content of the diet they consume. We investigated the dietary preferences of two grasshopper species (i.e. Asulconotus chinghaiensis and Chorthippus fallax) in terms of the C/N composition of plant species consumed, and determined whether this affected the egg production of unparasitized and parasitized grasshoppers by flies in a Tibetan alpine meadow. The composition of plants consumed differed significantly between the unparasitized and parasitized grasshoppers. Specifically, the abundance of N‐rich legumes was lower and that of high C/N grasses was higher in the diet of the parasitized compared to the unparasitized grasshoppers. Diet N content was higher and C/N was lower in the diet of unparasitized grasshoppers, and parasitized females produced fewer eggs than their unparasitized conspecifics. Future enquiries are needed to understand the specific mechanisms underlying these dietary differences. The effects of parasites on the fitness–associated behavior of hosts should be studied more broadly to better understand parasite evolution and adaptation. [ABSTRACT FROM AUTHOR]

Scholars have explored the factors influencing new product adoption from various perspectives, such as product characteristics, personality traits, and marketing communication strategies. However, these studies lack the consideration of consumer social relationships. Thus, this study examined how social exclusion influences new product adoption. Three experiments involving 1372 participants indicated that social exclusion leads to a higher really new products adoption compared to social inclusion. The mediating factor in this relationship is the need for uniqueness. In contrast, no significant difference in incrementally new product adoption was found between socially excluded and included individuals. The above effects only exist in individuals with low self‐control. Individuals with high self‐control exhibit no significant difference in RNP adoption intention, whether they experience social exclusion or inclusion. These findings not only significantly increase the body of knowledge on social exclusion and new products, but also advise marketers on how to promote new products. [ABSTRACT FROM AUTHOR]

In the past two decades, metamaterial design has been applied to terahertz wave detection research, which is very important because metamaterial has the advantages of high absorption, ultra-thin device thickness, design flexibility and frequency selectivity. In this paper, the VO2/Graphene heterostructures were designed on the silicon dioxide layer, and the terahertz wave absorption bandwidth was tuned by adjusting the size and conductivity of VO2 and the Fermi level of graphene. According to the simulation results, the VO2/Graphene heterostructures has a substantial absorption bandwidth of more than 7 THz and an absorption peak intensity that is continuously tuned between 2.8% and 98% by adjusting temperature change the conductivity of VO2. Meanwhile, the heterojunctions also have high absorption ability for terahertz waves incident at different polarization angles. The new idea is provided by our research results for the design of heterojunction terahertz absorption devices. [ABSTRACT FROM AUTHOR]

This paper proposes a higher-order blended compact difference (BCD) scheme on nonuniform grids for solving the three-dimensional (3D) convection–diffusion equation with variable coefficients. The BCD scheme has fifth- to sixth-order accuracy and considers the first and second derivatives of the unknown function as unknowns as well. Unlike other schemes that require grid transformation, the BCD scheme does not require any grid transformation and is simple and flexible in grid subdivisions. Concurrently, the corresponding high-order boundary schemes of the first and second derivatives have also been constructed. We tested the BCD scheme on three problems that involve convection-dominated and boundary-layer features. The numerical results show that the BCD scheme has good adaptability and high resolution on nonuniform grids. It outperforms the BCD scheme on uniform grids and the high-order compact scheme on nonuniform grids in the literature in terms of accuracy and resolution. [ABSTRACT FROM AUTHOR]

Photooxidation aging, hygrothermal aging, and hot‐air aging are carried out on atactic polystyrene (aPS) samples formed by injection molding. It is interesting that microcrystals of atactic polystyrene are only found in photooxidation aging. This work proposes that high molecular weight atactic polystyrene can crystallize under photooxidation aging. It is a good addition to the research on the aspect of crystallization of atactic polystyrene. [ABSTRACT FROM AUTHOR]

Based on the high temperature and confining pressure conditions at different depths, triaxial high temperature mechanical tests were carried out on Longmaxi shale with horizontal and vertical bedding, respectively. The results show that shale's peak strength and deformation capacity increase with burial depth. The failure mode of shale is a typical brittle failure, and the brittle index can quantitatively describe the brittle mechanical behavior of shale. Because shale has an apparent thin bedding structure, shale with different bedding directions shows pronounced anisotropy in mechanical parameters and deformation characteristics. The burial depth and bedding direction significantly impact the energy evolution law of Longmaxi shale during the mechanical process. [ABSTRACT FROM AUTHOR]