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This study aims to investigate the effects of the case depth and hardness distribution of carburizing on the rolling contact fatigue (RCF) properties of G20CrNi2MoA steel under deeper carburizing conditions. Four groups of specimens of different case depths are prepared and subjected to RCF tests. A 2D finite element model based on continuum damage mechanics is developed to further analyze these two factors. As the depth of the carburized case increases, the RCF life first increases and then decreases. The optimum case depth is approximately one‐quarter of the thickness of the specimen. A gentler hardness distribution due to a change in the diffusion process parameters ensures a minimal increase (8%) in the RCF performance. The proper case depth has a more notable effect on the RCF life compared with those of the gentle or steep hardness distribution. It is expected that the results can help to promote a better understanding of the heat treatment process of carburized bearings and ensure more reliable carburized bearings are produced. [ABSTRACT FROM AUTHOR]

The stable and site-specific operation of transmission lines is a crucial safeguard for grid functionality. This study introduces a comprehensive optimization design method for transmission line crossing frame structures based on the Biogeography-Based Optimization (BBO) algorithm, which integrates size, shape, and topology optimization. By utilizing the BBO algorithm to optimize the truss structure's design variables, the method ensures the structure's economic and practical viability while enhancing its performance. The optimization process is validated through finite element analysis, confirming the optimized structure's compliance with strength, stiffness, and stability requirements. The results demonstrate that the integrated design of size, shape, and topology optimization, as opposed to individual optimizations of size or shape and topology, yields the lightest structure mass and a maximum stress of 151.4 MPa under construction conditions. These findings also satisfy the criteria for strength, stiffness, and stability, verifying the method's feasibility, effectiveness, and practicality. This approach surpasses traditional optimization methods, offering a more effective solution for complex structural optimization challenges, thereby enhancing the sustainable utilization of structures. [ABSTRACT FROM AUTHOR]

The monotypic genus Ogdenia Peckham, 1908, is redefined based on the redescription of the holotype of O. mutilla (Peckham & Peckham, 1907), along with the newly discovered male specimens and intraspecific variation from China, Malaysia, Singapore, and Vietnam. Description, illustrations, and photographs are provided. [ABSTRACT FROM AUTHOR]

Visual Simultaneous Localization and Mapping (VSLAM) estimates the robot's pose in three-dimensional space by analyzing the depth variations of inter-frame feature points. Inter-frame feature point mismatches can lead to tracking failure, impacting the accuracy of the mobile robot's self-localization and mapping. This paper proposes a method for removing mismatches of image features in dynamic scenes in visual SLAM. First, the Grid-based Motion Statistics (GMS) method was introduced for fast coarse screening of mismatched image features. Second, an Adaptive Error Threshold RANSAC (ATRANSAC) method, determined by the internal matching rate, was proposed to improve the accuracy of removing mismatched image features in dynamic and static scenes. Third, the GMS-ATRANSAC method was tested for removing mismatched image features, and experimental results showed that GMS-ATRANSAC can remove mismatches of image features on moving objects. It achieved an average error reduction of 29.4% and 32.9% compared to RANSAC and GMS-RANSAC, with a corresponding reduction in error variance of 63.9% and 58.0%, respectively. The processing time was reduced by 78.3% and 38%, respectively. Finally, the effectiveness of inter-frame feature mismatch removal in the initialization thread of ORB-SLAM2 and the tracking thread of ORB-SLAM3 was verified for the proposed algorithm. [ABSTRACT FROM AUTHOR]

This article presents a study on the fatigue damage behavior of SiCp/A356 composites in severe service conditions of brake discs. A representative volume element (RVE) was constructed using finite element modeling technology to simulate the microstructure characteristics of the composites which takes into account the fatigue characteristics of the matrix. The RVE was loaded with local strain components and temperature histories obtained through the simulation of the braking condition of an urban rail train. The study found that the alternating effect of compressive stress and residual tensile stress at the matrix near the interface, especially at the sharp corners of SiC particles, causes fatigue damage on the matrix. Brake temperature was identified as the main factor for thermal–mechanical fatigue damage of the brake disc, and the matrix near the high-temperature position of the friction surface was found to have the highest degree of damage and the fastest failure process. The fatigue microcrack morphology and micro-failure modes inside the RVE were in good agreement with those of SiCp/A356 brake disc, and the RVE was able to characterize the micro-fatigue failure behavior of the SiCp/A356 composites under service thermal–mechanical load. This article provides a novel approach for investigating the thermo-mechanical fatigue behavior of SiCp/A356 composites from macroscopic to microscopic. [ABSTRACT FROM AUTHOR]

The earth pressure balance (EPB) shield tunneling efficiency is greatly affected by the choice of soil transport mode. In this study, the influence of two soil transport modes, such as the continuous belt conveyor and rail train, on the efficiency of shield excavation was analyzed using the Markov chain model. A method was proposed to define the ideal and non-ideal excavation states and quantitatively evaluate the excavation efficiency of the two soil transportation modes of the EPB shield. Based on this model framework, a profitable Markov chain model was established to predict the expected profits of the two soil transportation modes. The Beijing Metro New Airport Line first-phase project was used as a case study to verify the model established. The results show that under the same conditions, the continuous belt conveyor soil transport mode can have a higher excavation efficiency and expected profit. This advantage gradually increases over time. [ABSTRACT FROM AUTHOR]

A multi‐phase permanent magnet synchronous motor (PMSM) with fractional‐slot windings is proposed to reduce electromagnetic vibration and improve torque performance. Firstly, the analytical expression of electromagnetic force is derived, and the stator teeth modulation effect of electromagnetic force is introduced. The spatial order of the electromagnetic force and the stator teeth modulation are closely related to the slot‐pole combination of the PMSM. Then, three PMSMs with different slot‐pole combinations are presented, and they represent fractional‐slot concentrated winding, integral‐slot distributed winding and fractional‐slot distributed winding, respectively. Their torque performance and electromagnetic vibration performance are studied and compared considering stator teeth modulation. In addition, the multi‐phase winding technology is adopted to further improve the torque performance of the proposed PMSM. Finally, a 90s20p PMSM is manufactured, and the finite element method and experimental method are used to verify the proposed low vibration design method. [ABSTRACT FROM AUTHOR]

N6-methyladenosine (m6A) methyltransferase-like 3 (METTL3) has been confirmed to be involved in multiple myeloma (MM) progression, and basic leucine zipper and W2 domains 2 (BZW2) is considered to be a regulator for MM development. However, whether METTL3 mediates MM progression by regulating BZW2 remains unclear. The messenger RNA (mRNA) and protein levels of METTL3 and BZW2 in MM specimens and cells were determined using quantitative real-time PCR and western blot analysis. Cell proliferation and apoptosis were assessed by cell counting kit 8 assay, 5-ethynyl-2′-deoxyuridine assay, colony formation assay, and flow cytometry. Methylated RNA immunoprecipitation-qPCR was used to detect the m6A modification level of BZW2. Xenograft tumor models were constructed to confirm the effect of METTL3 knockdown on MM tumor growth in vivo. Our results showed that BZW2 was upregulated in MM bone marrow specimens and cells. BZW2 downregulation reduced MM cell proliferation and promoted apoptosis, while its overexpression enhanced MM cell proliferation and inhibited apoptosis. METTL3 was highly expressed in MM bone marrow specimens, and its expression was positively correlated with BZW2 expression. BZW2 expression was positively regulated by METTL3. Mechanistically, METTL3 could upregulate BZW2 expression by modulating its m6A modification. Additionally, METTL3 accelerated MM cell proliferation and restrained apoptosis via increasing BZW2 expression. In vivo experiments showed that METTL3 knockdown reduced MM tumor growth by decreasing BZW2 expression. In conclusion, these data indicated that METTL3-mediated the m6A methylation of BZW2 to promote MM progression, suggesting a novel therapeutic target for MM. [ABSTRACT FROM AUTHOR]

How do consumers combine multiple risk items when forming overall risk judgments? Drawing on the fuzzy trace theory and categorical averaging, this research finds that adding a low-risk item to a high-risk item reduces the overall risk perception because people reason categorically about risk. They impose categorical distinctions on quantitative risk information, and when combining categorical information, they tend to average across categories instead of adding. Eight studies in the context of medical and health product decisions (N  =   5,152) provide convergent evidence showing that when items in different risk tiers are considered together, they are consistently evaluated in a subtractive manner, leading to a higher likelihood of taking the objectively riskier medication (studies 1A, 1B, 1C, and 2). This effect is eliminated when the probability of one side effect is exceedingly high (study 3) or when the task requires reliance on verbatim representation of probabilities (study 4). The effect also disappears when risk information is presented graphically in a way that emphasizes the additive property of multiple risks (studies 5A and 5B). The findings have important implications for the fields of risk perception, risk communication, and consumer health and medical decision-making. [ABSTRACT FROM AUTHOR]

Here, we report an ultracompact angular displacement sensor based on the Talbot effect of optical microgratings. Periodic Talbot interference patterns were obtained behind an upper optical grating. By putting another grating within the Talbot region, the total transmission of the two-grating structure was found to be approximatively in a linear relationship with the relative pitch angle between the two gratings, which was explained by a transversal shift of the Talbot interference patterns. The influence of the grating parameters (e.g., the grating period, the number of grating lines and the gap between the two gratings) was also studied in both a simulation and an experiment, showing a tunable sensitivity and range by simply changing the grating parameters. A sensitivity of 0.19 mV/arcsec was experimentally obtained, leading to a relative sensitivity of 0.27%/arcsec within a linear range of ±396 arcsec with the 2 μm-period optical gratings. Benefitting from tunable properties and an ultracompact structure, we believe that the proposed sensor shows great potential in applications such as aviation, navigation, robotics and manufacturing engineering. [ABSTRACT FROM AUTHOR]

This work focuses on the development of a three-dimensional shield tunneling model coupling the finite-difference method (FDM) with the discrete-element method (DEM) and evaluates its tunneling performance in boulders. The tunneling process of cutterhead rotation, cutting the formation, soil entering the chamber, and discharging of the screw conveyor is simulated to explain the characteristics of particle movement in front of the tunnel face. The range of the soil failure zone under different shield discharge ratios is determined by the correlation between the discharge ratio and the tunnel surface stability. The evolution process of the soil arching effect in the boulders along with shield tunneling is investigated to understand the mechanisms of the delay settlement in the boulders. Subsequently, the shield discharge ratio is optimized by investigating its influence on the surface deformation. Finally, the average stress distribution on the shield cutterhead in the tunneling process is analyzed to provide the scheme of the cutterhead structure and arrangement. This work can be referred for evaluating the shield tunneling performance and optimizing the excavation design scheme of shield machines during tunneling construction under similar geological conditions. The coupled finite-difference method (FDM)–discrete-element method (DEM) calculation method proposed in this study was successfully applied for boring tunnel equipment performance analysis in Beijing Metro Line 16. This shield tunnel was excavated in the strata with boulders rich in large size and high strength, and the previous tunneling experience shows that the shield is prone to encountering accidents such as tool damage and cutterhead jamming by large boulders when tunneling in such strata. Based on the present parametric analysis and calculation results, the suitable engineering suggestions have been proposed to enhance the shield equipment specifically, such as strengthening the central and peripheral cutters and the wear resistance of the cutterhead sides. In addition, the cutterhead opening and band-type screw conveyor were also adjusted to allow large size stones to pass through the cutterhead and discharge from the soil chamber as much as possible instead of being broken by the cutters. The adoption of these techniques has made it possible for the earth pressure balance shield (EPBS) machine to continuously excavate 1,300 m in boulders without cutter exchanges. [ABSTRACT FROM AUTHOR]

The cutterhead of an earth pressure balance (EPB) shield usually relies on a large torque when tunneling through a water-rich and high-permeability sand layer. Sandy soils may lead to severe wear of the cutter tools and make the screw conveyor vulnerable to spewing. In this study, we investigate the characteristics of the soil conditioned by means of foam, bentonite slurry, and carboxymethyl cellulose solution. The mechanical and friction properties of the conditioned soil were tested by the triaxial shear, Laboratoires Central des Ponts et Chaussees (LCPC), and sliding tests, under considering the influence of soil consolidation time. The test results showed that the conditioned sand presents dilatancy, and its cohesion enhances but its internal friction angle decreases. The changing trend of these properties is more prominent with the increase of consolidation time but they stabilize after 12 h. The starting torque of the shield machine in 3-h shutdown reaches 60% of the rated torque, while the starting torque in 6-h shutdown exceeds 80% of the rated torque. To avoid a large starting torque, we suggest that the cutterhead is idled for a short time within 12 h after the shield machine is shutdown. Finally, the theoretical calculation method of torque on cutterhead was developed, and the prediction by such method is in good agreement with the in situ measured data in the cutterhead. [ABSTRACT FROM AUTHOR]

The enhanced application performance of hollow-structured materials is attributed to their large surface area with more active sites. In this work, the hollow CoSn(OH)6 nanocubes with increased surface area and mesopores were derived from dense CoSn(OH)6 nanocube precursors by alkaline etching. As a result, the hollow CoSn(OH)6 nanocubes-based cathode electrode exhibited a higher area-specific capacitance of 85.56 µF cm−2 at 0.5 mA cm−2 and a mass-specific capacitance of 5.35 mF g−1 at 0.5 mA cm−2, which was more extensive than that of the dense precursor. Meanwhile, the current density was increased 4-fold with good rate capability for hollow CoSn(OH)6 nanocubes. [ABSTRACT FROM AUTHOR]

The Area under the ROC curve (AUC) is a well-known ranking metric for problems such as imbalanced learning and recommender systems. The vast majority of existing AUC-optimization-based machine learning methods only focus on binary-class cases, while leaving the multiclass cases unconsidered. In this paper, we start an early trial to consider the problem of learning multiclass scoring functions via optimizing multiclass AUC metrics. Our foundation is based on the M metric, which is a well-known multiclass extension of AUC. We first pay a revisit to this metric, showing that it could eliminate the imbalance issue from the minority class pairs. Motivated by this, we propose an empirical surrogate risk minimization framework to approximately optimize the M metric. Theoretically, we show that: (i) optimizing most of the popular differentiable surrogate losses suffices to reach the Bayes optimal scoring function asymptotically; (ii) the training framework enjoys an imbalance-aware generalization error bound, which pays more attention to the bottleneck samples of minority classes compared with the traditional $O(\sqrt{1/N})$ O (1 / N) result. Practically, to deal with the low scalability of the computational operations, we propose acceleration methods for three popular surrogate loss functions, including the exponential loss, squared loss, and hinge loss, to speed up loss and gradient evaluations. Finally, experimental results on 11 real-world datasets demonstrate the effectiveness of our proposed framework. The code is now available at https://github.com/joshuaas/Learning-with-Multiclass-AUC-Theory-and-Algorithms. [ABSTRACT FROM AUTHOR]

Accurate lung tumor segmentation has great significance in the treatment planning of lung cancer. However, robust lung tumor segmentation becomes challenging due to the heterogeneity of tumors and the similar visual characteristics between tumors and surrounding tissues. Hence, we developed an improved 3D dense connected UNet (I-3D DenseUNet) to segment various lung tumors from CT images. The nested dense skip connection adopted in the I-3D DenseUNet aims to contribute similar feature maps between encoder and decoder sub-networks. The dense connection used in encoder-decoder blocks also encourages feature propagation and reuse. A robust data augmentation strategy was employed to alleviate over-fitting based on a 3D thin plate spline (TPS) algorithm. We evaluated our method on 938 lung tumors from three datasets consisting of 421 tumors from the Cancer Imaging Archive (TCIA), 450 malignant tumors from the Lung Image Database Consortium (LIDC), and 67 tumors from the private dataset. Experiment results showed an excellent Dice similarity coefficients (DSC) of 0.8316 for the TCIA and LIDC and 0.8167 for the private dataset. The proposed method presents a strong ability in lung tumor segmentation, and it has the potential to help radiologists in lung cancer treatment planning. [ABSTRACT FROM AUTHOR]

When excavating tunnels in the clay stratum by using earth pressure balance (EPB) shields, the cutterhead is prone to clogging and may lose its ability to excavate. To investigate the clogging mechanism, a cutterhead device equipped with a driving system was developed to emulate the cutterhead behavior of the EPB shield in conditioned soils. The influences of water content, consolidation time, and soil conditioning factors on clay adhesion were evaluated and compared based on general laboratory and cutterhead model tests. The mixing test results showed that the water content influenced considerably clay adhesion. A water content interval near the liquid limit caused a decrease in the adhesion coefficient, and the change in water content was more effective than that in clay conditioning. Direct shear tests revealed that soil conditioning could reduce clay strength, and the effect was evident when the consolidation time was less than 6 h. A peeling point was observed in the adhesion curve of the clay and steel blocks. The peeling point for unconditioned clay was greater than the corresponding shear failure strength, which indicated that the clay had failed before it was detached from the steel block surface. However, contrasting results were obtained for conditioned clay. The cutterhead model test also showed that the water content had the greatest influence on clay adhesion according to the torque and thrust. [ABSTRACT FROM AUTHOR]

The present study investigates the distribution and geological characteristics of cobbles and boulders in the southwestern area in Beijing to provide a basis for the subway engineering design and construction process. An abundance of boulders with large particle sizes in the underground leads to a challenge to the construction of metro tunnels. Based on drilling exploration, the exploration shaft method is used to investigate the distribution of large-size boulders in the soil. The spatial distribution of boulders was determined, and it was found that large-size boulders were mainly distributed at burial depths of 17–19 m, with a maximum particle size of 67 cm, and the total boulder content reached a maximum of 48%. The physical and mechanical properties of the cobbles and boulders were tested in the laboratory. The results show that the size distribution of boulders at the same depth exhibits a large dispersion, and boulder strength is positively correlated with size. Furthermore, the mineral composition analysis indicates that the equivalent quartz content (EQC) is the main factor in determining the geological characteristics of the pebbles. Additionally, it is found that the EQC of the pebbles is strongly correlated with the uniaxial compressive strength and Cerchar abrasivity index value, and larger-size pebbles result in higher EQC values. [ABSTRACT FROM AUTHOR]

A lot of researches on continuous carbon-fiber composite laminates have been conducted, but no scrutiny has been devoted to continuous carbon-fiber composite honeycomb sandwiches. This paper is aimed to assess the design and properties aspects of honeycomb sandwiches made of continuous carbon-fiber composite laminates. The applicability of the existing theoretical formulas for the mechanical properties of isotropic material honeycomb sandwich on continuous carbon-fiber composite honeycomb is examined by comparing the obtained results from the finite-element modeling and experimental results. The results reveal that the theoretical formulas of isotropic material honeycomb sandwich in density and out-of-plane compressive elastic modulus are suitable for continuous carbon-fiber composite honeycomb, while other performances cannot be achieved by theoretical formulas of isotropic material honeycomb sandwiches. The out-of-plane compression and shear properties of continuous carbon-fiber composite honeycomb can be evaluated by finite-element modeling. The effects of cell side length, wall thickness, and 45° ply content on the honeycomb density, out-of-plane compression properties and out-of-plane shear strength are researched. Subsequently, the out-of-plane compression experiments of honeycomb are carried out to show the accuracy of the finite-element modeling. Finally, a design approach for continuous carbon-fiber composites honeycomb structures is proposed. This methodology results in the design of honeycomb sandwiches with better performances. The chief innovation of this paper is to develop the concept of continuous carbon-fiber composite honeycomb sandwich structures. To this end, a honeycomb structure finite-element model of continuous carbon-fiber composite is established, and the mechanical properties of continuous carbon-fiber composite honeycomb sandwiches are explored. A methodology for the rapid design of honeycomb size parameters of continuous carbon fiber composite honeycomb sandwich is also proposed. [ABSTRACT FROM AUTHOR]

Soil conditioning of an earth pressure balance shield in a saturated sand layer aims to impart adequate flow plasticity and impermeability. Thus, the effect of soil conditioning on the saturated sand layer was analyzed for Harbin Metro Line 2 in the tunnel section project from Harbin North Station to Dagengjia Station, and the optimal soil conditioning ratio was obtained through experiments on medium sand using foam, bentonite, and carboxymethyl cellulose. In addition, the microscopic pores and shape characteristics of the soil before and after conditioning were compared using computerized tomography (CT) scanning and scanning electron microscopy (SEM) to evaluate the microscopic effect of soil conditioning. The current research results revealed that the soil conditioning reduced the particle size dispersion and improved the particle gradation, and the conditioned soil particles were more uniform than the original soil sample. Moreover, the CT scanning images processed using the threshold method illustrated that the pores of the conditioned soil were independent of each other, no continuous channels were formed, and the porosity of each layer was under 4%. In addition, the SEM images confirmed that the clay mineral composition improved the angularity and sharpness of the sand particles, and the flocculent aggregate structure, formed in combination with the sand particles, reduced the soil permeability. Furthermore, the practical application of the optimal ratio of conditioning materials, obtained experimentally and verified through the aforementioned observation, yielded proper results in the field construction, and the spewing of the screw conveyor during the shield tunneling process was avoided. [ABSTRACT FROM AUTHOR]

The time–temperature superposition (TTS) is a data processing method of viscoelastic mechanics, which is realized by translating and superposing the responses at different temperatures to get master curves beyond the test time or frequency. In this study, an automatic shift method is developed to obtain master surfaces of the carbon fiber reinforced plastics and epoxy resin. First step, an interpolation is used to process the dynamic mechanical analysis test data measured by frequency sweep/temperature step or continuous heating‐up method. Second step, the Prony series of the generalized Maxwell model are used to fit the storage and loss modulus at each temperature, which makes the fitting curves have physical meaning and causality. Third step, the automatic shift is achieved by minimizing the sum of squares of the vertical distances between two fitting curves. Last step, master surfaces are created by Prony series fitting and interpolation, and the storage modulus, loss modulus, loss factors, and relaxation modulus at any temperature, frequency or time can be found on the master surfaces. Both storage modulus and loss modulus are considered at same time according to the weight. The effects of different weights are studied. [ABSTRACT FROM AUTHOR]

Although many calculation methods for tunnel face support pressure have been proposed, they are difficult to use in practical applications. In tunneling, the tunnel support pressure is currently being determined by empirical methods. In this study, five special geological sections were selected based on the shield tunnel project between Wangfujing and Qianmen Stations of Beijing Metro Line 8 to evaluate the different support pressure ratios λ by using the particle flow code (PFC). Both the stress distribution in the ground and the settlement under different support states were analyzed. A simplified limit-equilibrium method was developed in combination with the limit state in the PFC model. The present method was compared with the classical limit-equilibrium calculation methods to predict the active limit support pressure in the tunnel face. The values of the minimum limit support pressure ratio λmin of the tunnel face were suggested. The results showed that such ratio should be set to 0.6–0.7, which implies that the change in the support pressure cannot be less than 0.6 times of the true strata stress before excavation. The present calculation method of the limit support pressure is simple and effective and can be used in the design and construction of shield tunnel engineering. [ABSTRACT FROM AUTHOR]

• The failure modes and causes of Cr12Mo1V1 crimping die were clarified. • The life extension measures of the dies were put forward. • The simulation model of multi-body contact deformation is constructed by Deform software. • The structure designs of the electrical connector dies were optimized. A type of Cr12Mo1V1 electric connection die occured brittle fracture after 200 times of service, and its life was much lower than the design life of the die. In this paper, the 5M1E failure analysis method was adopted, combined with the characteristics of Cr12Mo1V1 cold-work die steel, scanning electron microscopy, direct reading spectrometer, Rockwell hardness tester, metallographic microscope and other means were used to analyze and test the macro fracture morphology, material composition, mechanical properties and microstructure of Cr12Mo1V1 electric connection die. The crimping process of the die was simulated by Deform software. The results show that the material composition is not up to standard, the strength is too low, the internal eutectic carbide is not uniform, the size of carbide exceeds the standard and so on are the root causes of the short life and brittle fracture of the die. In addition, the unreasonable designs of the crack slot and round hole of the die lead to excessive stress concentration in the crimping process of the die, which is too the main reason for the brittle fracture failure of the die. In view of the above factors, the paper puts forward some measures to prolong the life of the electric connection die from the aspects of raw materials, heat treatment, forging process and die structure design. [ABSTRACT FROM AUTHOR]

• Coupled rolling contact fatigue elastic-plastic damage model for carburized bearing steel. • Characterization of rolling contact fatigue with different thicknesses of carburized layer. • Relationship between the number of load cycles and the degree of subsequent material damage. • Optimization of carburizing heat treatment process for bearing steel. Being a pivotal element within high-speed train transmission systems, the mechanical attributes of bearings are of great significance to ensure the quality and safety of train operation. In this study, the rolling contact fatigue performance of bearing materials was tested to investigate the effects of different carbon layer characteristics on the rolling contact fatigue behavior. Combined with the thickness of carburizing layer, the elastoplastic coupling model of rolling contact fatigue damage of G20CrNi2MoA carburizing bearing steel was established. The model revealed the relationship between the number of load cycles and the degree of subsequent material damage. The model was used to calculate and predict the loading frequency of G20CrNi2MoA carburized bearing steel with excellent fatigue characteristics, which was 2.02 × 108 times before spalling. In addition, the carburizing heat treatment process for bearings was optimized based on the hardness gradient curves obtained, which provided valuable insights for improving the actual production process. [ABSTRACT FROM AUTHOR]

In this paper, we study the problem of estimating subjective visual properties (SVP) for images, which is an emerging task in Computer Vision. Generally speaking, collecting SVP datasets involves a crowdsourcing process where annotations are obtained from a wide range of online users. Since the process is done without quality control, SVP datasets are known to suffer from noise. This leads to the issue that not all samples are trustworthy. Facing this problem, we need to develop robust models for learning SVP from noisy crowdsourced annotations. In this paper, we construct two general robust learning frameworks for this application. Specifically, in the first framework, we propose a probabilistic framework to explicitly model the sparse unreliable patterns that exist in the dataset. It is noteworthy that we then provide an alternative framework that could reformulate the sparse unreliable patterns as a “contraction” operation over the original loss function. The latter framework leverages not only efficient end-to-end training but also rigorous theoretical analyses. To apply these frameworks, we further provide two models as implementations of the frameworks, where the sparse noise parameters could be interpreted with the HodgeRank theory. Finally, extensive theoretical and empirical studies show the effectiveness of our proposed framework. [ABSTRACT FROM AUTHOR]

Background: The number of patients who suffer from glioma has been increasing, and this malignancy is a serious threat to human health. The mainstream treatment for glioma is surgical resection; therefore, accurate resection can improve postoperative patient recovery. Purpose: Many studies have investigated surgical navigation guided by mixed reality, with good outcomes. However, the limitations of mixed reality, such as spatial drift caused by environmental changes, limit its clinical application. Therefore, we present a mixed reality surgical navigation system for glioma resection. Preoperative information can be fused precisely with the real patient with the spatial compensation method to achieve clinically suitable accuracy. Methods: A head‐mounted device was used to display virtual information, and a markerless spatial registration method was applied to precisely align the virtual anatomy with the real patient preoperatively. High‐accuracy preoperative and intraoperative movement and spatial drift compensation methods were used to increase the positional accuracy of the mixed reality‐guided glioma resection system when the patient's head is fixed to the bed frame. Several experiments were designed to validate the accuracy and efficacy of this system. Results: Phantom experiments were performed to test the efficacy and accuracy of this system under ideal conditions, and clinical tests were conducted to assess the performance of this system in clinical application. The accuracy of spatial registration was 1.18 mm in the phantom experiments and 1.86 mm in the clinical application. Conclusions: Herein, we present a mixed reality‐based multimodality‐fused surgical navigation system for assisting surgeons in intuitively identifying the glioma boundary intraoperatively. The experimental results indicate that this system has suitable accuracy and efficacy for clinical usage. [ABSTRACT FROM AUTHOR]

Transparent displays suffer from background image blur due to light diffraction when passing through periodic pixel structures. A simple, reference‐image free and semi‐analytical model based on diffraction theory and human eye's angular resolution is proposed to quantitatively evaluate the diffraction effect of transparent displays. Several factors including object distance, resolution and aperture ratio are analyzed with our model to establish guidelines for minimizing the diffraction effect in transparent displays. By optimizing the pixel structures within a 2 × 2‐pixel size region, the relative diffraction intensity is reduced by 42% at the 50% aperture ratio regardless of pixel density, which is valuable for achieving diffraction‐less high resolution and low aperture ratio transparent displays with current fabrication technologies. [ABSTRACT FROM AUTHOR]

It is important to estimate the cumulative distribution function (CDF) of a failure mode in a geotechnical system, because failure of the mode is often characterized by some empirical and/or semi‐empirical thresholds and geotechnical engineers sometimes might be interested in the probability of failure associated with various thresholds. The geotechnical systems also generally contain multiple failure modes. This requires an efficient estimation of cumulative distribution functions (CDFs) of multiple failure modes, which poses a significant challenge in application of conventional geotechnical reliability analysis methods. To address this challenge, this study proposes an advanced generalized subset simulation‐based method (AGSS) to efficiently estimate the CDFs of multiple failure modes of the geotechnical system. The proposed method utilizes the probability weights of samples generated in each sample sub‐space to efficiently estimate the CDFs, instead of using the conditional probability formula that may yield incorrect CDFs due to the sample "jumping" properties existing in generalized subset simulation (GSS). A cantilever retaining wall example and a parallel system example are employed to demonstrate the proposed method. It is found that the proposed method can effectively estimate the CDFs of multiple failure modes with high computational efficiency. [ABSTRACT FROM AUTHOR]

Synchronous grouting has a very important effect on shield tunnel, which directly affects the stability of excavation face and the safety of segment structure. Testing the setting time and early strength of mortar is conducive to timely control the surface settlement and prevent the segment from floating. The flow table test can ensure that synchronous grouting can fill the excavation gap of shield machine to the greatest extent. Oedometer test can obtain physical and mechanical indexes such as elastic modulus, Poisson's ratio, compression and drainage of slurry at different ages. The test results showed that the use of well-graded, small-sized machine-made gravel (0–5 mm) and natural sand (0–2 mm) with high-efficiency additives promoted the formation of early strength in grout and reduced the probability of plugging in the grouting pipe at the tail shield. The oedometer test results indicated that the quantity of water drained from a grout mixed for more than 2 h was stable and the grout deformation within 1 h of compression accounted for 80% of the total deformation. The Young's modulus of the grout reached 10 MPa when the grouting pressure was > 0.2 MPa, meeting the requirements for field injection. In this study, an efficient synchronous grouting mixture proportion suitable for calcareous sand layer is proposed, and the performance of slurry in fresh state is obtained through a variety of tests, which can be widely used in shield tunnels in similar strata. [ABSTRACT FROM AUTHOR]

There is a wide demand for people counting and pedestrian flow monitoring in large public places such as scenic tourist areas, shopping malls, stations, squares, and so on. Based on the feedback from the pedestrian flow monitoring system, resources can be optimally allocated to maximize social and economic benefits. Moreover, trampling accidents can be avoided because pedestrian guidance is carried out in time. In order to meet these requirements, we propose a method of pedestrian flow monitoring based on the received signal strength (RSS) of wireless sensor networks. This method mainly utilizes the shadow attenuation effect of pedestrians on radio frequency (RF) signals of effective links. In this paper, a deployment structure of RF wireless sensor network is firstly designed to monitor the pedestrians. Secondly, the features are extracted from the wavelet decomposition of RSS signal series with a short time. Lastly, the support vector machine (SVM) algorithm is trained by an experimental data set to distinguish the instantaneous number of pedestrian passing through the monitoring point. In the case of dense and sparse indoor personnel density, the accuracy of the SVM model is 88.9% and 94.5%, respectively. In the outdoor environment, the accuracy of the SVM model is 92.9%. The experimental results show that this method can realize the high precision monitoring of the flow of people in the context of real-time pedestrian flow monitoring. [ABSTRACT FROM AUTHOR]

• SiCp/A356 composite material pre-damage thermal cycling treatment. • Cross scale microscopic observation and microscopic damage mechanism analysis. • Analysis of mechanical performance degradation and friction mechanism. • SiCp/A356 composite material long-term service temperature should be controlled below 200 °C. During bench tests and actual service, the Al-MMC (metal matrix composite) brake discs used in urban rail transit vehicles experienced problems such as poor wear resistance, compromising the brake discs' stability and safety. While braking, the brake disc material will bear the thermal cycling loads, leading to a certain degree of degradation in the material's performance. In this study, the degradation of the material's performance by the thermal cycling treatment was investigated. The results showed that all material performance degraded to some extent after thermal cycling treatment, with a strong correlation with cycling temperature. The degradation of material performance was caused by a combination of matrix mechanical damage and interface damage. At the same time, the tribological performance of the material also decreased to some extent. The main effect of thermal cycling treatment on tribological performance was its effect on material performance. The increase of hard particles in the abrasive debris resulting from the mechanical damage of the material and the aggravation of the dynamic changes in the TBL (third body layer) were the basic reasons for the surface scratches. The results further help to explore the application of Al-MMCs in high-temperature and long-term service. [ABSTRACT FROM AUTHOR]

The strong, transient, and high-peak impact load caused by a vehicle entering water at high speed is the primary factor threatening its structural strength and equipment safety. One of the effective methods for water entry protection is to use head-mounted buffer components. To this end, based on the arbitrary Lagrangian-Eulerian method, a numerical model of impact load reduction of water entry was established in this study. The results showed that the impact load could be characterised by a narrow pulse width and a high peak value, which gradually stabilises in a fluctuating manner. Five typical stages in the failure process of the cushion foam and four typical stages in that of the nose cap were observed. The prediction accuracy decreased as the scaling ratio decreased. Furthermore, the buffer components increased the occurrence of an error in the prediction results of the scaling model. The primary causes are the strain-rate sensitivity of the foam and dissimilarity in the failure criteria, which lead to dissimilarities in the foam failure process after scaling. This research will be useful for the designing of water load reduction structures and scaled model experimental schemes. [ABSTRACT FROM AUTHOR]

Aiming at the gait control problem of a snake‐like inspection robot performing variable‐diameter spiral motion on high‐voltage cables, a gait generation method is proposed here, the snake‐like robot can adapt to the change in diameter when it is winding around the obstacles of high‐voltage cables. The piecewise helix is fitted with the Bezier curve of degree 3, which solves the problem of discontinuous speed and abrupt change of joint angle when the snake‐like robot moves with variable diameter, and avoids periodic motion impact. The new idea provides for the application of a snake‐like robot on high‐voltage cables. [ABSTRACT FROM AUTHOR]

As an effective learning paradigm against insufficient training samples, multi-task learning (MTL) encourages knowledge sharing across multiple related tasks so as to improve the overall performance. In MTL, a major challenge springs from the phenomenon that sharing the knowledge with dissimilar and hard tasks, known as negative transfer, often results in a worsened performance. Though a substantial amount of studies have been carried out against the negative transfer, most of the existing methods only model the transfer relationship as task correlations, with the transfer across features and tasks left unconsidered. Different from the existing methods, our goal is to alleviate negative transfer collaboratively across features and tasks. To this end, we propose a novel multi-task learning method called task-feature collaborative learning (TFCL). Specifically, we first propose a base model with a heterogeneous block-diagonal structure regularizer to leverage the collaborative grouping of features and tasks and suppressing inter-group knowledge sharing. We then propose an optimization method for the model. Extensive theoretical analysis shows that our proposed method has the following benefits: (a) it enjoys the global convergence property and (b) it provides a block-diagonal structure recovery guarantee. As a practical extension, we extend the base model by allowing overlapping features and differentiating the hard tasks. We further apply it to the personalized attribute prediction problem with fine-grained modeling of user behaviors. Finally, experimental results on both simulated dataset and real-world datasets demonstrate the effectiveness of our proposed method. [ABSTRACT FROM AUTHOR]

Slope reliability analyses considering spatially variable soil properties generally necessitate a discretization of a slope region into disjoint zones called random field elements (RFEs). Few efforts have been devoted to investigating the effect of RFE size on the assessment of reliabilities and risks of slopes possibly due to the huge computational burdens associated with a small RFE size. This study systematically investigates the influence of RFE size on statistics of factor of safety (FS) and sliding mass (SM), distribution of critical slip surfaces, reliability, and risk of slopes. As the size of RFE is small, a stepwise covariance matrix decomposition method (CMDM) is used to effectively simulate the random field of the shear strength parameter. This stepwise CMDM is justified using a simple and straightforward method. Monte Carlo simulation (MCS) is employed to estimate the probability of failure and risk of slopes. Three cohesive slopes are adopted to investigate the effect of RFE size on the statistics of FS and SM, distribution of critical slip surfaces, system reliability, and risk of the slope. It is shown that the RFE size has a relatively larger influence on the distribution of SM than that of FS. A relatively larger size of RFE tends to overestimate the slope failure probability and risk. The critical size of RFE required for an accurate evaluation of the statistics of FS and SM is smaller than that required for the evaluation of failure probability and risk. [ABSTRACT FROM AUTHOR]

A solenoid magnetic field plays an important role in a non-line-of-sight azimuth transmission system based on polarization-maintaining fiber, which is directly related to the transmission accuracy of azimuth information. This research mainly studies the factors that affect the solenoid magnetic field according to the modulation signal from the direct current to the alternating current, as well as the hollow solenoid. First, the magnetic field components of the static solenoid are derived from the Biot–Savart law by using the uniform cylindrical current equivalent model. Then, the magnetic field of the near axial region is studied from the axial and radial directions, and the feasibility of calculating the magnetic field of the multi-layer solenoid with the superposition principle is verified by measuring the magnetic field of each position on the axis of the solenoid with a Gauss meter. Finally, the alternating electromagnetic field model is established using Maxwell's equations, and the magnetic and electric fields of the hollow solenoid are further solved. The results show that the magnetic field in the middle part of the magneto-optic glass is more stable, and the magnetic collecting ability of the solenoid is stronger. The magnetic field intensity at the center of the magneto-optic modulation solenoid of the system is the largest, and it decreases with the distance from the center. The alternating electromagnetic field is closely related to frequency. The results provide a reference for the study of the azimuth accuracy of a non-line-of-sight azimuth transmission system. [ABSTRACT FROM AUTHOR]

Cutting tool wear in tunnel boring machine (TBM) affects the construction safety, time, and cost in tunneling engineering. To accurately calculate the wear of TBM cutting tools used in heterogeneous grounds, the wear coefficient was studied theoretically and using field experiments based on the tool wear model proposed by the Japanese Tunnelling Society (JTS). A trajectory weight-based wear coefficient was proposed along with a calculation method that enhanced the model's adaptability to heterogeneous grounds. The conclusions were as follows: (1) The wear coefficients for cutting tools installed at different installation radii had to be calculated separately due to their dissimilar values in heterogeneous grounds. (2) Analysis of measured data proved that the distribution of strata in the excavation area, the wear coefficient of each ground, and the cutting tools installation radius all significantly influenced the heterogeneous ground wear coefficient. A comparison of results obtained using different calculation models showed that the model proposed in this paper was more suitable for the calculation of tool wear in heterogeneous soil strata. (3) When the JTS model and its optimization model were used, the wear of high and low cutting tools had to be calculated separately due to dissimilar wear. (4) Based on the example analyses, the wear coefficients for high rippers were 102.31–113.73 μm/km, for low rippers were 35.94–42.55 μm/km, and for scrapers were 38.60–40.34 μm/km. The wear coefficient of the low ripper and scraper was approximately 40% of that of the high ripper, and the correction coefficient for the outermost scraper and ripper was 1.2–1.4 and 2–3, respectively. [ABSTRACT FROM AUTHOR]

Purpose: This paper aims to confirm that increasing the hardness of thrust collars can improve the load carrying capacity (LCC) and wear resistance of water lubricated thrust bearings (WTBs) made of polymers paired with non-polymeric thrust collars, and to design a WTB with high LCC and durability for a shaftless pump-jet propulsor of an autonomous underwater vehicle. Six kinds of WTBs were manufactured by matching aluminum bronze, stainless steel and silicon nitride with two different polymer bearing materials. Their tribological behaviors were tested and compared. Design/methodology/approach: The tribological behaviors of the WTBs made with different materials were investigated experimentally on a specially designed test rig. Findings: Aluminum bronze is not suitable for crafting thrust collars of heavy load WTBs due to severe abrasive wear. Two body abrasive wear first occurred between the thrust collar and the polymer bearing. Next, aluminum bronze wear particles were produced. The particles acted between the two materials and formed three body abrasive wear. Stainless steel/polymer bearings showed better wear resistance while Si3N4/polymer bearings were the best. Improving the hardness of thrust collars is significant to the LCC and service life of WTBs. Originality/value: The wear mechanism of WTBs under heavy load conditions was revealed. Improving the hardness of the thrust collar was confirmed to be a preferable method to improve the wear resistance and LCC of WTBs. The results of this study may provide an important reference for the selection of water lubricated materials and the design of heavy load WTBs. [ABSTRACT FROM AUTHOR]

Recently, "liquid crystal display (LCD), organic light‐emitting diode (OLED), or micro‐light‐emitting diode (LED): who wins?" is a heated debatable question. In this review article, we provide a comprehensive overview of these three promising display technologies through nine display performance indicators, including ambient contrast ratio, motion picture response time, viewing angle and angular color shift, color gamut, resolution density, power consumption, cost, lifetime, and thin profile and panel flexibility. The advantages and disadvantages of each technology are analyzed, and their future perspectives are discussed. [ABSTRACT FROM AUTHOR]

A computer‐aided detection (CADe) scheme, relying on a large number of high‐quality images with annotations, could help radiologists effectively detect lung nodules. However, such medical data are generally difficult to obtain. To address this issue, this paper proposes a novel method based on a conditional generative adversarial network (CGAN) to generate new samples for data augmentation (DA). This method employs a 3D CGAN based on a squeeze‐and‐excitation mechanism and residual learning to synthesize realistic and diverse lung nodules in chest computed tomography (CT) images to improve the performance of the CADe system. To evaluate the proposed method, this paper uses synthetic samples for DA to train the lung nodule detection network. The results indicate that these synthetic samples, which cover a part of the data distribution unfilled by the original data, can boost the overall performance of the nodule detection network at fixed false positive (FP) rates. [ABSTRACT FROM AUTHOR]

Over the past 25 years, friction stir welding (FSW) tools have evolved from simple cylindrical geometries to complex conical profiles which incorporate flutes, threads, and multiple facets. Due to the limits of physical testing, finite element (FE) modeling is widely used to analyze FSW tool behavior. However, simulation accuracy is dependent on the tool/work interface conditions and the heat source model that is used. While a uniform probe/workpiece interface conditions are typically assumed in most heat source models, recent work indicates that slip rates on curved (lobe) and flat (facet) surfaces differ considerably. In the present work, a quick stop device was used to observe the steady-state interface conditions for a hexagonal (three lobes and three facets) probe and a generalized heat source model is proposed for asymmetric tools having an arbitrary number of surfaces. A 3D finite element model based on FLUENT was also developed and used to simulate three different probe configurations. A comparison of simulated and experimental temperature profiles showed good agreement and confirmed that heat generation increases with the number of probe facets but approaches a limit as lobes begin to approximate facet surfaces at small edge lengths. Analysis of FSW welds showed that increasing the number of facets promotes lateral flow and results in a wider plasticized zone. It is expected that the study findings will be useful in improving the accuracy of heat source models and understanding how probe geometry affects welding behavior. [ABSTRACT FROM AUTHOR]

A polarization‐independent refractive index (RI) sensor with a sensitivity of 50 nm/RIU is demonstrated. The proposed RI sensor simply consists of a liquid crystal (LC) polymeric polarization grating film and one glass substrate. The wavelength shift over the RI of the surrounding medium is investigated through anisotropic rigorous coupled‐wave analysis. Such an LC‐based polarization‐independent RI sensor not only enables the usage of an unpolarized light source but also manifests a high sensitivity, offering great potential for the integration with display systems. [ABSTRACT FROM AUTHOR]

This article presents a personalized mixed reality (MR) surgical assistance system for brachytherapy. Using a novel, modified multi-information fusion method, the fusion of virtual organs and a preoperative plan for an actual patient and the real-time tracking of surgical tools were achieved. Using the quaternion-based iterative closest point (QICP) algorithm and a hand-eye calibration method, the preoperative plan can be fused into individual patients. Using the electromagnetic (EM) tracker, users can track the surgery tools in real time, without multiple CT scans, and doctors can immediately perform the surgery. We performed a series of experiments, including phantom and animal experiments, to test the accuracy and efficiency of the system. In the phantom experiment, the average needle location error was 0.957 mm. Based on the results of animal experiments, the needle insertion error was 2.416 mm. All experimental results indicated that the procedure could be applied in further clinical studies. [ABSTRACT FROM AUTHOR]

In site investigation, it is common to conduct some soundings to explore greater depths that are not explored by remaining soundings. This produces the scenario of nonlattice data, meaning that not all soundings measure identical depths. Recently in 2020, the first and third authors of the current paper developed a probabilistic site characterization method based on sparse Bayesian learning (SBL). This SBL method assumes lattice data (all soundings measure identical depths) to take advantage of the Kronecker-product derivations. These Kronecker-product derivations significantly improve computation efficiency, so the resulting SBL method can be scaled up to address full-scale three-dimensional problems. However, this SBL method is not applicable to nonlattice data, which are common in practice. The purpose of the current paper is to modify the SBL method developed in 2020 to accommodate nonlattice data, while retaining the crucial computational advantage of the Kronecker-product derivations. One real-world case study of underground stratification is used to demonstrate the usefulness of the modified method. [ABSTRACT FROM AUTHOR]

This paper considers the robust recovery problem of sparse signal with sparse Bayesian learning (SBL) in noisy environments. Most of the current SBL algorithms are constructed on the optimization problem using the square loss, which mainly deals with Gaussian noise. However, real measurements are often contaminated by an unknown distributed noise that is unlikely to be Gaussian. To prevent performance degradation of SBL in such cases, we propose a robust sparse Bayesian learning method with a simple but effective hierarchical noise model. Using this model, the resultant loss is made up of a weighted error measure and a priori-dependent constraint on the weight, and then provides the flexibility for resisting the outliers and adapting to the real noise. A type-II Bayesian estimate is performed to infer the related model parameter and the unknown sparse signal. The advantage of our method is demonstrated by extensive experiments on synthetic data and real radio tomographic imaging data. [ABSTRACT FROM AUTHOR]

This paper focuses on the influence of particle size distribution, test time, and moisture content on the Laboratoire Central des Ponts et Chaussées (LCPC) abrasivity coefficient (LAC). Image analysis and X-ray diffraction were used to analyze the particle shape characteristics and equivalent quartz content (EQC) of a sandy stratum. The test results show no significant differences in the shape characteristics and EQC of particles with different diameters obtained from the same sandy stratum. For the same EQC, the main factors affecting the LAC are particle size distribution, test time, and moisture content. An optimized effective size (ESop) index was established to represent different particle size distributions. The test results showed that the ESop index is more accurate than other indices in determining the LAC of soil samples, and the LAC had a linear relationship with the ESop index. Soil samples with moisture content less than the saturated moisture content have an LAC larger than that of a dry soil sample, and soil samples with moisture content greater than the saturated moisture content have an LAC similar to that of a dry soil sample. The influence of test time on the LAC of the soil samples could be divided into two stages, where the first and second stages are represented by a quadratic function and a linear function, respectively. [ABSTRACT FROM AUTHOR]

Bromodomain 4 (BRD4), a member of the bromodomain and extra‐terminal domain protein family, has become a promising epigenetic target in cancer and inflammatory diseases; however, the detailed biological role of BRD4 in breast cancer (BRCA) remains undetermined. We analysed the BRD4 expression levels using the Oncomine and TIMER databases and evaluated the clinical impact of BRD4 on BRCA prognosis using Kaplan‐Meier plot and PrognoScan. The correlation between BRD4 and tumour‐infiltrating immune cells was investigated using TIMER. Furthermore, the correlation between BRD4 expression levels was also analysed using TIMER in addition to the GEPIA database for immune cell gene markers. BRD4 expression was significantly higher in BRCA tissues than in normal tissues, which was significantly correlated with poor overall survival (OS). Specifically, high BRD4 expression was correlated with worse OS and progression‐free survival in patients with BRCA. In addition, BRD4 expression was correlated with levels of infiltrating monocytes (CSF1R, cor = 0.204, P = 9.19e−12), tumour‐associated macrophages (CD68, cor = 0.129, P = 1.81e−05), M1/M2 macrophages and different effector T cells (including Th1/Th2/Treg) in BRCA. These findings suggest that BRD4 could be used as a prognostic biomarker for determining prognosis and immune cell infiltration levels in BRCA. [ABSTRACT FROM AUTHOR]

Objective: This meta‐analysis aimed to determine whether liposomal bupivacaine (LB) single‐injection could achieve an analgesic effect similar to that of continuous local anesthetic nerve blocks (CNBs) after painful surgeries. Methods: Embase, PubMed, and the Cochrane Library databases were comprehensively searched. Randomized controlled trials (RCTs) with a modified Jadad score ≥ 4 compared LB single‐injection with CNBs in patients after painful surgeries were included. The primary outcomes were VAS pain score and opioid consumption. The secondary outcomes were complications and length of hospital stay. Review Manager 5.3 and trial sequential analysis (TSA) 0.9.5.10 were used to analyze the extracted data. Results: Six RCTs of 625 patients were included for meta‐analysis. Both groups in 5 RCTs described standard concomitant treatment with multimodal analgesia. There were no significant differences in mean VAS scores for postoperative day 0 (P = 0.12), day 1 (P = 0.18), and day 2 (P = 0.41); highest VAS scores for day 0 (P = 0.18), day 1 (P = 0.46), and day 2 (P = 0.18); total opioid consumption for day 0 (P = 0.05), day 1 (P = 0.28), and day 2 (P = 0.57); complications (P = 0.30); and length of hospital stay (P = 0.64) between the 2 groups. TSA of primary outcomes showed that all cumulative Z curves failed to cross the TSA boundary and did not reach the required information size. Conclusions: This meta‐analysis showed that LB single‐injection and CNBs have similar efficacy of pain relief and safety in patients after painful surgeries when concomitant with multimodal analgesia. However, the results of TSA indicate that further trials are still needed to confirm these findings. [ABSTRACT FROM AUTHOR]

Retrievals of satellite aerosol optical depth (AOD) products are used for studies of air pollution, energy balance, and climate change. However, few studies have evaluated the diurnal time representation (DTR) of satellite AOD products. In this study, we proposed a statistically valid threshold method to investigate the DTR of Moderate Resolution Imaging Spectroradiometer (MODIS), Visible Infrared Imaging Radiometer Suite (VIIRS), Multi-angle Imaging Spectroradiometer (MISR), and Advanced Himawari Imager (AHI) AOD products by comparing their retrievals to the daily AERONET AOD values and explored the ability of AHI and AERONET to capture daily aerosol variability at 54 sites in Asia and Oceania from July 2015 to December 2019. For polar-orbiting satellites, based on collocations with AERONET measurements, MISR-derived AOD showed high consistency with daily average AERONET AOD, with a correlation coefficient (R) of 0.94 and 80.85% matchups falling into the envelopes of expected error (EE, ± (0.05 + 0.15 × AOD AERONET)). Compared with single MODIS products, a combination of satellite data from the Terra and Aqua MODIS dark target (DT) algorithm might obtain a dataset with better DTR (R = 0.94 and %Within EE = 72.10). The satellite-retrieved AOD did a good job to represent the daily mean AERONET AOD, because AERONET AOD averaged within a ± 30 min time window of different satellite overpasses closely mirrored the daily mean AERONET AOD. Furthermore, the seasonal average diurnal variations (SADV) of AERONET AOD were changing insignificant, except for the urban coverage area in the Southern Hemisphere and equatorial climate. For geostationary satellite, the DTR of AHI was relatively poorer in comparison to the other sensors (R = 0.84, %Within EE = 58.00), and AHI AOD was seriously underestimated in South Asia and overestimated in Oceania. Besides, the SADVs of AHI AOD presented several patterns summarized as wave type, unimodal type, stable fluctuation type, and other types, which meant that AHI AOD retrievals did not accurately capture the diurnal variability of aerosols. This study provides a reference for the aerosol community to select satellite AOD products with appropriate DTR. • Diurnal time representations of MODIS, VIIRS, MISR, and AHI are verified. • Satellite-derived AOD does a good job to represent daily mean AERONET AOD. • Pseudo daily average AERONET AOD closely mirrors daily mean AERONET AOD. • AHI AOD retrievals do not accurately capture the diurnal variability of aerosols. [ABSTRACT FROM AUTHOR]

This study aimed to detect the relationship between nickel exposure and body mass index (BMI), waist circumference and incidence of obesity in the general population of the United States. The National Health and Nutrition Examination Survey (NHANES) 2017–2018 database was utilized, and the sample comprised 1702 participants aged 18 years and above with complete urinary nickel, body mass index, and waist circumference data. Obesity was determined using BMI and waist circumference data. The multivariate linear regression and logistic regression models were utilized to detect the association between urinary nickel concentration and BMI, waist circumference, and incidence of obesity. After multivariable adjustment, the log-transformed urinary nickel concentration was inversely associated with BMI [β = −0.87; 95% confidence interval (CI): (−1.36, −0.38)] and waist circumference [β = −1.51; 95% CI: (−2.93, −0.08)]. Compared with the lowest tertile of urinary nickel, the β value and 95% CI of BMI and waist circumference for the highest tertile were β = −1.65.95% CI: (−2.85, −0.45) and β = −2.78, 95% CI: (−6.17, 0.62), respectively. The log-transformed urinary nickel concentration was also negatively associated with obesity status [adjusted odds ratio (OR) = 0.81, 95% CI: (0.64, 1.01)]. Compared with the lowest tertile of urinary nickel, the adjusted OR and 95% CI of obesity status for the highest tertile were OR = 0.64 and 95% CI: (0.37, 1.12). Smooth curve fitting and the generalized additive model indicated that elevated urinary nickel concentration was associated with decreased BMI, waist circumference, and incidence of obesity. The negative association was consistent and robust in different subgroups, according to stratified analysis. This study found that nickel exposure may be negatively associated with BMI, waist circumference and incidence of obesity in US Adults. [Display omitted] • Relationship between nickel exposure and obesity status was studied in US adults. • Urinary nickel level was negatively associated with BMI and waist circumference. • Nickel exposure may be negatively associated with incidence of obesity. [ABSTRACT FROM AUTHOR]

• This paper extends the quantile-based first-order second-moment method into an inverse-reliability method. • The proposed inverse-reliability method operates in the physical space, not in the standard normal space. • For reliability-based design, the inverse-reliability method is more efficient than the direct method. • The proposed inverse-reliability method is more efficient than that based on first-order reliability method. Quantile-based first-order second-moment method is a novel reliability analysis method proposed by the authors that is with simplicity and efficiency close to the first-order second-moment method, yet with accuracy and robustness close to the first-order reliability method. However, the quantile-based first-order second-moment method is inefficient if directly applied to reliability-based design. The novelty of the current short communication is to re-formulate the quantile-based first-order second-moment method into inverse-reliability methods to enhance computational efficiency. Two inverse-reliability methods are proposed based on this re-formulation. One is more practical, whereas the other is often more efficient. The effectiveness of the proposed methods is illustrated by a friction pile design example and a spread footing design example for the National Geotechnical Experimentation Sites at Texas A&M University. [ABSTRACT FROM AUTHOR]