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This study introduced a hydrogel dressing, termed SODex-gel, which was constructed by establishing Schiff base and hydrogen bonds with the precursors of oxidized dextran (ODex) and succinic dihydrazide (SD)-modified sodium alginate (SD-mod-SA). Through comprehensive in vitroand in vivostudies, the adhesive properties, self-healing capabilities, hemostatic potential, and wound healing efficacy of the SODex-gel dressing were meticulously evaluated. The 1H NMR, FTIR, and TGA analyses confirmed the fabrication of the SODex-gel dressing and its constituent elements. Scanning electron microscopy (SEM) imaging showcased the uniform pore structures in the SODex-gel dressing. In vitroassessments demonstrated that the SODex-gel dressing was noncytotoxic and exhibits strong adhesion, enabling it to attach to various surfaces. Noteworthy findings from studies of mouse liver incisions and tail amputation models proved the hemostatic ability of the SODex-gel dressing. Moreover, their remarkable wound-healing capabilities were prominently demonstrated through the treatment of a mouse model afflicted with burn skin injuries. Evidence of neovascularization effects was corroborated by the upregulation of CD31 and vascular endothelial growth factor (VEGF) expression in the treated skin samples. Collectively, the experimental data unequivocally established that the SODex-gel dressing is a promising therapeutic approach to accelerate wound recovery, thereby exhibiting substantial potential for clinical applications in treating burn injuries.

Reforming carbon dioxide (CO2) into fuels and valuable chemicals using solar energy holds significant potential for emission reduction and addressing energy supply challenges. The recombination of photocarriers remains a major obstacle, however, to enhancing solar energy conversion efficiency in the photocatalytic reaction process. For two-dimensional materials, constructing heterogeneous structures has emerged as an effective strategy to enhance the separation of photoexcited carriers by leveraging the internal electric field at the heterogeneous interface. Herein, we present a facile strategy for preparing Bi4NbO8Br /Bi2WO6plate-on-plate Z-scheme junctions with a strong internal electric field by in situsynthesis. This unique heterostructure facilitates efficient separation and transport of photoexcited charges by harnessing the internal electric field induced by chemical bonding at the lateral interface. Impressively, the Bi4NbO8Br/Bi2WO6heterostructure exhibits enhanced CO2photoreduction properties, along with a CO yield rate of approximately 35 μmol·g−1·h−1under full light illumination. This work offers novel insights into the synthesis of unique heterostructures intended to enhance the efficiency of photocatalytic CO2reduction.

Pyroptosis, a form of programmed cell death, holds great promise for breast cancer treatment. However, the downregulation of gasdermin E (GSDME) limits the effectiveness of pyroptosis. To address this challenge, we developed a folic acid-modified and glutathione/reactive oxygen species dual-responsive nanocarrier (FPSD NPs) for the targeted delivery of doxorubicin (DOX). Through the combination with DNA methyltransferase inhibitor decitabine (DAC), the GSDME protein expression was significantly increased in 4T1 cells, resulting in cell swelling and ballooning, which are characteristic features of pyroptosis. In vivo experiments further demonstrated the antitumor efficacy of DAC + DOX@FPSD NPs, and the 4T1-bearing mice treated with DAC + DOX@FPSD NPs exhibited reduced tumor volumes, minimized tumor weights, decreased Ki67-positive cells, increased TUNEL apoptosis ratios, and pronounced lesions in H&E staining. Furthermore, DAC + DOX@FPSD NP treatment could promote pyroptosis-associated antitumor immunity, as evidenced by the increased presence of CD3+, CD4+, and CD8+T cells, heightened secretion of tumor necrosis factor-α and interferon-γ, elevated high-mobility group box-1 levels, and enhanced calreticulin exposure. The FPSD nanocarrier developed in this study had favorable stability, active targeting ability, biocompatibility, and controlled release properties, and the DAC + DOX@FPSD NPs represented an approach to antitumor therapy by inducing pyroptosis, which offers a promising avenue for breast cancer treatment.

Graphical abstract: Boosting the catalytic ability of MoS2is vital to its further application as a class of promising non-noble catalysts to address environmental issues. Benefiting from the O-doping-induced electronic effect and interfacial coupling and synergistic effect between MoS2and reduced graphene oxide (rGO), the as-prepared O-MoS2&rGO heterogeneous catalyst exhibits enhanced degradation efficiency for methylene blue (MB) dye.

Ultrasound-assisted processes, widely applied in cleaning, synthesis, and catalysis, exhibit significant application potential, with their impact rooted in the interplay between ultrasound and the physicochemical properties of substances. Therefore, it is emphasized here to understand these processes through a “sono-physico-chemical” angle for a deeper comprehension of reaction mechanisms and broader application. Highlighting cavitation and vibration effects, the ultrasound-assisted chemistry processes are categorized. Cavitation is emphasized for pollutant degradation, while vibration is primarily applied for inducing the piezoelectric effect. Additionally, points that are easy to be ignored in the current ultrasonic assisted catalysis process are proposed, such as synergistic index calculations, cost assessments, etc. Furthermore, the latest innovative application of ultrasonic assisted process in wastewater recycling is introduced. Finally, the review advocates for the future integration of ultrasound-assisted processes into new catalytic processes or application scenarios.

The deep oceans harbor a wide variety of mineral resources that are characterized by their abundance and high quality. Nations worldwide are actively pursuing the exploration and extraction of these resources. This paper provides a concise overview of the mineral resources found in the deep sea, highlighting the challenges associated with their exploitation. Furthermore, it presents a comprehensive analysis of the historical development of deep-sea mining technology and equipment, offering valuable insights into this field. By examining the current issues and obstacles faced in deep-sea mineral extraction, this study concludes that the future of deep-sea mining lies in the direction of automation, intelligence, and standardization. Additionally, it identifies the key technological advancements that need to be achieved in order to overcome the challenges associated with deep-sea mining.

The optimum fragmentation size measures the quality of a blasting operation. Boulders or large fragments can result in more costs because they need secondary blasting, while small fragments can result in ore loss and dilution. Therefore, it is very significant to accurately predict the mean block size to reduce production costs and enhance efficiency. Due to the shortfalls of the empirical models, scholars have been inclined toward artificial intelligence (AI) techniques for fragmentation size prediction over the decades. Firstly, in this study, three tree-based models, i.e., the random forest (RF), extra-trees (ET), and CatBoost (CB), are employed for basic prediction. The model uses eight parameters, seven input parameters, and mean block size (MBS) as the output parameter. Secondly, their performance and hyper-parameters were fine-tuned using Bayesian optimization: tree-structured Parzen estimators (TPE) algorithm using Optuna. Among the three models, the TPE-ET model showed superior performance with the following metric scores on the training dataset: 0.9896, 0.0184, and 0.0003, and on the test dataset with the following metric scores: 0.9463, 0.0415, and 0.0017, i.e., R2, RMSE, and MSE, respectively. In conclusion, analysis by the SHapley Additive ExPlanations approach shows that elastic modulus significantly impacts the model’s prediction of rock fragmentation.

A total of nine new phenolic amides (1–9), including four pairs of enantiomeric mixtures (3–5and 8), along with ten known analogues (10–19) were identified from the fruits of Lycium barbarumusing bioassay-guided chromatographic fractionation. Their structures were elucidated by comprehensive spectroscopic and spectrometric analyses, chiral HPLC analyses, and quantum NMR, and electronic circular dichroism calculations. Compounds 5–7are the first example of feruloyl tyramine dimers fused through a cyclobutane ring. The activity results indicated that compounds 1, 11, and 13–17exhibited remarkable inhibition against α-glucosidase with IC50of 1.11–33.53 μM, 5–150 times stronger than acarbose (IC50= 169.78 μM). Meanwhile, compounds 4a, 4b, 5a, 5b, 13, and 14exerted moderate agonistic activities for peroxisome proliferator-activated receptor (PPAR-γ), with EC50values of 10.09–44.26 μM. Especially,compound 14also presented inhibitory activity on dipeptidyl peptidase-4 (DPPIV), with an IC50value of 47.13 μM. Furthermore, the banding manner of compounds 14and 17with the active site of α-glucosidase, DPPIV, and PPAR-γ was explored by employing molecular docking analysis.

Ceramic matrix composite (CMC), with higher thermal limit and lower density relative to the superalloy, is regarded as the most important structural material for modern gas turbine engines. However, the anisotropic thermal conductivities caused by the weave patterns totally change the thermal conduction performance inside the solid domain. Therefore, the present study aims to use the infrared thermographic to measure the SiC/SiC composite platform with staggered effusion holes along with the superalloy platform. CMC platform is prepared by 2-D plain weave braid structure with chemical vapor infiltration (CVI) process. The temperature of mainstream is 900 K to match the real mainstream to coolant temperature ratio (Tg/Tc=1.5, 2.1). The experimental was conducted with seven mass flow ratios (MFR=1.5%–4.5%). The results indicate that the thermal conductivity along the thickness direction is of great importance for the CMC platform. The superalloy platform obtains higher level of overall cooling effectiveness than CMC at Tg/Tc=1.5. However, the CMC platform achieves greater overall cooling effectiveness relative to superalloy at Tg/Tc=2.1. In addition, CMC platform presents enhanced uniformity of overall cooling effectiveness due to the larger in-plane thermal conductivity.

ABSTRACTThis study focuses on a problem that has been seriously troubled urban traffic managers: the impact of underground excavation metros on surface traffic safety during construction. In underground construction, surface subsidence and road collapse due to concealed underground construction constantly occur, resulting in casualties property damage and seriously impairing normal urban road traffic. Urban road managers urgently need a quick, objective, and easy-to-use method for the early warning and prevention of such risks. Therefore, this study collates relevant accident cases that have occurred in China over the last 20 years and summarises the impact mechanisms of concealed underground works affecting surface road traffic capacity through a detailed study of natural factors, engineering geology, types of structures, and types of workmanship. Two indices, Rank() and , are proposed to describe the impact of concealed underground works on surface traffic capacity, while an early warning method based on data on the impact of urban road capacity by concealed underground works is established using integrated learning methods and is well applied in practical projects. The results of this study are important for helping city managers quickly assess urban road traffic risks.

Graphical abstract: A new hybrid supercapacitor with excellent electrochemical performance is fabricated by electrostatic hetero-assembly of positively charged 1D KCu7S4and negatively charged 2D titanium carbide (Ti3C2) MXene.

For unshrouded blade tip, the high-temperature gas flows through the tip clearance by force of the lateral pressure difference. Thereby, the blade tip endures increasing thermal load. Furthermore, the conventional blade tip treatment cannot continuously provide protection for the deteriorating service environment. In the present study, aerothermal characteristics of the squealer blade tip with staggered ribs, partial squealer rim and different partial squealer rim thickness were investigated to explore the influences of ribbed-cavity tip on the tip heat transfer, leakage flow and turbine stage efficiency. The numerical results indicate that the ribbed-cavity tips are beneficial for the reduction of the blade tip thermal load and leakage flow. Among the present six blade tip designs, the minimal area-averaged heat transfer coefficient is obtained by the case with the staggered ribs and a deeper squealer rim, which is reduced by 31.41% relative to the squealer tip. Plus, the blade tip modification closer to leading edge or tip mid-chord region performs better than trailing edge in reducing the tip leakage flow.

The secondary flow originated from the inherent pressure gradient inside the vane cascade has a strong impact on the endwall cooling performance as the crossflow sweeps the upstream coolant jet towards the suction side, resulting in intensifying thermal load near the pressure side endwall. Hence a novel ribbed-endwall is introduced to suppress passage crossflow. The effects of the mass flow ratio and the rib layout were examined using numerical simulations by solving the three-dimensional Reynolds-averaged Navier-Stokes (RANS) equations with the shear stress transport (SST) k-ωturbulence model. The results indicate that the ribs effectively prevent the coolant migrating from the pressure side to the suction side, helping the coolant jet to spread along the lateral orientation. Therefore, the endwall adiabatic film cooling effectiveness is substantially improved. The maximum cooling effectiveness is achieved for the case with three-ribs when the height of the rib equals one hole diameter among all cases. The area-averaged adiabatic cooling effectiveness is enhanced by 31.6% relative to the flat endwall when the mass flow ratio of coolant to mainstream equals to 0.52%. More importantly, the ribbed-endwall obtains a relatively lower level of aerodynamic loss owing to the reduced lateral migration inside the vane cascade.

•Utilizing Alphafold2 to predict the variable region structure of antibodies, successful humanization modification was carried out on murine-derived antibody 4D11.•H4D11-hIgG1 (S267E), due to its epitope recognition at the N-terminus of CD40, exhibits a stronger activation capability compared to APX005M.•The activation function of H4D11-hIgG1 (S267E) relies on cross-linking interactions.•BA4415, a novel anti-PD-L1/CD40 bispecific antibody, designed to selectively activate CD40 signaling in the context of PD-L1 while concurrently inhibiting PD-1/PD-L1 signaling.•BA4415 demonstrates outstanding anti-tumor efficacy.

Both tannic acid and epigallocatechin gallate belong to natural polyphenolic compounds, commonly used as additives in the food industry. However, excessive intake of these substances is harmful to human health, necessitating monitoring and analysis. In this study, a coordination compound of amino acid/iron with peroxidase-like activity was synthesized using the coprecipitation method in an aqueous solution. Using 3,3′,5,5-tetramethylbenzidine (TMB) as a chromogenic substrate, the compound can oxidize colorless TMB to a blue substance in the presence of hydrogen peroxide, with natural polyphenolic compounds exhibiting inhibitory effects on this colorimetric reaction. Based on this, a colorimetric detection platform for tannic acid (TA) and epigallocatechin gallate (EGCG) was established using the amino acid complex at 25 °C and pH 3.5. The linear detection ranges were found to be 0.5–5.5 μM and 0.1–0.46 mM for the two compounds, with the respective lowest detection limits of 0.16 μM and 11 μM. The simple and cost-effective amino acid-based nanozyme constructed in this study holds significant application potential in the field of future food safety.

Rockburst, coal bump, and mine earthquake are the most important dynamic disaster phenomena in deep mining. This paper summarizes the differences and connections between rockburst, coal bumps and mine earthquakes in terms of definition, mechanism, phenomenon, evaluation index, etc. The definition and evolution progress of the three disaster categories are summarized, as well as the monitoring, early warning, and prevention measures are also presented. Firstly, by combining theoretical research with specific technologies and engineering field cases, the main categories and failure mechanisms of rockburst, coal bumps and mine earthquakes are introduced. Then, the evaluation indexes of coal bump and mine earthquake are summarized, and a new evaluation index of rockburst is given. Finally, the characteristics of monitoring, early warning technologies and prevention methods of rockburst, coal bumps, and mine earthquakes are discussed in technology and application. At last, the future directions of rockburst, coal bump and mine earthquake are put forward.

Electrocatalytic reduction of nitrogen into ammonia (NH3) is a highly attractive but challenging route for NH3production. We propose to realize a synergetic work of multi reaction sites to overcome the limitation of sustainable NH3production. Herein, using ruthenium-sulfur-carbon (Ru-S-C) catalyst as a prototype, we show that the Ru/S dual-site cooperates to catalyse eletrocatalytic nitrogen reduction reaction (eNRR) at ambient conditions. With the combination of theoretical calculations, in situRaman spectroscopy, and experimental observation, we demonstrate that such Ru/S dual-site cooperation greatly facilitates the activation and first protonation of N2in the rate-determining step of eNRR. As a result, Ru-S-C catalyst exhibits significantly enhanced eNRR performance compared with the routine Ru-N-C catalyst viaa single-site catalytic mechanism. We anticipate that our specifically designed dual-site collaborative catalytic mechanism will open up a new way to offers new opportunities for advancing sustainable NH3production.

The waste rock and tailings backfill into the mined-out areas are the most effective method for solving the environmental pollution and surface disasters for nonferrous metals mines. In practice, the success and availability of backfill operations are dependent on the slurry fluidity and the strength properties of cement backfill. The transport of the slurry through the pipeline to the designated backfilling area relies on its eximious flow properties, while the appropriate strength of the filling body ensures the safe operation of the stope. In this paper, the effects of cement and aggregate types on the slurry fluidity and strength characteristics of cemented backfill are studied in detail, which are often ignored in other pieces of literature. Diffusivity is used as an indicator to evaluate the slurry fluidity. Various slurries whose concentrations ranging from 70%, 73%, 75%, 78%, and 80% are made with different aggregate ratios and cement-sand ratios are tested. It has been shown that slurry fluidity is inversely related to its concentration, but 78% is the “stopping point” for the deterioration of fluidity. The addition of rod-milled sand improves or worsens the cemented backfill (CB) strength depending on the amount of rob-milled sand. The uniaxial compression experiment results on 216 CB specimens produced by different combinations of influencing variables showed that CB specimens made from cement with superior mechanical properties have a higher uniaxial compressive strength (σucs). It has been also found that the effect of aggregate ratio on the CB strength is not singular, but works in conjunction with the curing time and the cement-sand ratio. The longer the curing time and the higher the cement content, the higher the CB’s σucs. To avoid the time-consuming and costly problem of obtaining the strength of the CB from indoor experiments, an SVR model capable of predicting the uniaxial compression strength of CB specimens is proposed, which is optimized by genetic algorithm (GA) and particle swarm optimization (PSO) algorithm. The results of the three performance indexes (MAPE, MSE, and R2) show the superior performance of the GA-SVR and PSO-SVR models and the agreement of the predicted results with the experimental results, which indicate that these two models can accurately predict the σucsof CB.

The occurrence of unpredictable hazards are frequent with the increased depth of mining, especially the hazards caused by stress concentration. In order to mitigate the negative effectiveness results from mining-induce stress, various approaches have been employed in underground mines. Destress blasting, as an efficient method, has gained a lot of popularity in recent years. However, it is crucial to estimate the destressability of specific area before conducting destress blasting. In this study a combination model on the basis of both unascertained measurement (UM) and entropy coefficients was applied to observe the performance of destressability evaluation. Eight representative parameters, i.e., stiffness of the rock mass, brittleness of the rock mass, degree of fracturing, proximity to failure, destress blast orientation, width of the target zone, unit explosive energy, and confinement of the charges were chosen as initial input parameters, and their membership distributions were described by four types of membership methodologies, i.e., line, parabolic curve, exponential curve, and sine curve. Meanwhile, the weights of each index could be computed based on the single measurement matrix. Then, destressability of the samples was easily identified with Euclidean distance and comprehensive measurement vectors which were computed by single measurement vectors and weight coefficients. Finally, it was found that the assessment results are in accordance with those calculated by destressability index. It can be concluded that the proposed hybrid model is able to eliminate the disturbance of subjective factors and ensure the reliability of these outcomes. At the same time, it can provide a novel idea/process for the destressability evaluation.

Isolated pillars in underground mines are subjected to uniaxial stress, and the load bearing cross-section of pillars is commonly rectangularly shaped. In addition, the uniaxial compression test (UCT) is widely used for determining the basic mechanical properties of rocks and revealing the mechanism of isolated pillar disasters under unidimensional stress. The shape effects of rock mechanical properties under uniaxial compression are mainly quantitatively reflected in the specific shape ratios of rocks. Therefore, it is necessary to study the detailed shape ratio effects on the mechanical properties of rectangular prism rock specimens and isolated pillars under uniaxial compressive stress. In this study, granite, marble and sandstone rectangular prism specimens with various height to width ratios (r) and width to thickness ratios (u) were prepared and tested. The study results show that rand uhave a great influence on the bearing ability of rocks, and thin or high rocks have lower uniaxial compressive strength. Reducing the level of rcan enhance the ueffect on the strength of rocks, and increasing the level of ucan enhance the reffect on the strength of rocks. The lateral strain on the thickness side of the rock specimen is larger than that on the width side, which implies that crack growth occurs easily on the thickness side. Considering rand u, a novel strength prediction model of isolated pillars was proposed based on the testing results, and the prediction model was used for the safety assessment of 179 isolated pillars in the Xianglu Mountain Tungsten Mine.

To investigate the ratio of Crown to Chin length (CCL) to Crown–rump length (CRL) between triploid and normal fetuses at first trimester and establish a reference range of fetal CCL/CRL ratio. Three hundred and twenty‐five normal and 12 triploid fetuses were reviewed in this study. The image of fetal Crown–rump length (CRL) was acquired retrospectively. CCL and CRL were measured offline by two experienced sonographers, we obtained each averaged value of CCL and CRL as the final data for analysis. A normal range of CCL was established and CCL/CRL ratio was analyzed in normal and triploid fetuses. In 325 normal fetuses, CCL increased with gestational age following a linear trend from 20 mm at a CRL of 45–36 mm at a CRL of 84 mm (CCL (mm) = 3.65 + 0.38 CRL, R2= 0.821, P= .000). The CCL/CRL ratio decreased with gestational age from a mean of 0.46 at a CRL of 45 mm to 0.41 at a CRL of 84 mm (PML/CRL = 0.502–0.001 CRL, R2= 0.093, P= .000). All 12 triploid fetuses had a CCL/CRL ratio above the 95th percentile. When the 95th percentile are used as cutoff values, the detection rate, false‐positive rate, and the positive likelihood ratio are 100%, 5%, and 20, respectively. The present study demonstrates that fetal CCL/CRL ratio can be used and effective ultrasound marker in screening for triploidy during the first trimester.

Background The preoperative prediction of the recurrence of chronic rhinosinusitis with nasal polyps (CRSwNP) remains difficult in clinical practice.Objective We aimed to develop a nomogram that combined peripheral risk factors to clinically predict the recurrence of CRSwNP.Methods Data from 158 CRSwNP patients who underwent endoscopic sinus surgery (ESS) from January 2012 to December 2016 were collected, and the patients were followed up for 3 years. Of these, 96 patients who underwent ESS in an earlier period formed the training cohort for nomogram development, and 62 patients who underwent ESS thereafter formed the validation cohort to confirm the model’s performance. Risk factors for recurrence identified by univariate and multivariate logistic regression were used to create a nomogram.Results The recurrence rate was 29.2% (28/96) for the training cohort and 35.5% (22/62) for the validation cohort. Univariate analysis identified blood eosinophils (Eos), serum IgE level, asthma comorbidity, and the number of previous ESSs as risk factors for recurrence. Among those four parameters, serum IgE level and a previous ESS surgery were identified as two independent risk factors. A nomogram consisting of blood Eos, total serum IgE level, asthma comorbidity, and the number of previous ESSs was constructed, demonstrating a C index of 0.81 (95% CI, 0.79-0.83) and 0.80 (95% CI, 0.77-0.83) for predicting recurrence in the training and validation cohorts, respectively. The nomogram had well-fitted calibration curves.Conclusion The nomogram might be able to preoperatively predict the recurrence of CRSwNP by using currently available and objective parameters. Further studies are required to validate its reliability and effectiveness.

Bursts in water distribution systems (WDSs) lead to water wastage and negative environmental impacts. Optimizing pressure sensor placement (PSP) for effective burst detection is crucial for prompt response and adverse event mitigation. While many optimization methods are available for this purpose, their resulting PSP strategies often exhibit large variability caused by background noise or metering accuracy, representing low robustness. This consequently hinders the wide application of existing PSP methods for burst detection in WDSs. This study proposes a novel multi‐objective PSP method aimed at maximizing burst detection while minimizing the number of sensors. Within this method, a new threshold metric is introduced to quantify the minimum detectable burst outflow across all pipes. The metric has the key advantage of taking into account the fact that the relative magnitude of the detectable threshold for different pipes is independent of noise, thereby addressing the low robustness issue. The proposed method is applied to three WDSs, and results show that it can consistently achieve robust optimal PSP strategies across diverse noise conditions. Comprehensive comparisons between the proposed method and the other benchmark approaches are conducted using five metrics, including detection performance and layout characteristics. These comparisons reveal the properties of each optimization method and show how detection performance is affected by various placement features. It is anticipated that the proposed method can be useful in engineering practice due to its great robustness in determining the optimal PSP strategies for burst detection in WDSs compared to other alternatives. In water distribution systems (WDSs), bursts can cause water wastage and environmental harm. Strategic pressure sensor placement (PSP) is crucial for prompt burst detection and mitigation. However, existing PSP methods often lack robustness due to background noise or metering inaccuracies, hindering their widespread use. This study introduces a novel multi‐objective PSP method aiming to maximize burst detection while minimizing sensor count. It includes a new threshold metric to quantify minimum detectable burst outflow, independent of noise, addressing the robustness issue. Based on results from three case studies, the proposed method consistently achieves optimal PSP strategies across diverse noise conditions. Comparative analyses with benchmark approaches demonstrate its robustness and effectiveness in detecting bursts. This method can be very useful in engineering as it can provide reliable PSP strategies for WDS burst detection. The proposed method deals with issues of low robustness and inconsistency within pressure sensor placementsFive metrics and three case studies are used for comparison between the proposed method and three existing approachesPlacements with a larger average shortest‐path distance outperform those with an average geographic‐plane distance in detection performance The proposed method deals with issues of low robustness and inconsistency within pressure sensor placements Five metrics and three case studies are used for comparison between the proposed method and three existing approaches Placements with a larger average shortest‐path distance outperform those with an average geographic‐plane distance in detection performance

Advanced and accurate prediction of rock fragmentation distribution can reduce the secondary crushing work, the cost of manual equipment and increase efficiency, thereby enabling tunnel excavation towards lightweighting. To that end, a novel hybrid random forest (RF) model optimized by atomic orbital search (AOS) with Logistic mapping (LM), i.e., LMAOS-RF, was proposed to predict rock size distribution. Five other hybrid models such as epsilon-support vector regression (e-SVR) and nu-support vector regression (n-SVR), backpropagation neural network (BPNN), extreme learning machine (ELM) and kernel extreme learning machine (KELM) optimized by arithmetic optimization algorithm (AOA) were also developed and compared to LMAOS-RF model. Eleven parameters including uniaxial compressive strength (UCS), blasting workface height (H), degree of bonding of bedding surface (DB), total number of holes (TNH), periphery holes spacing (SPH), relief holes spacing (SRH), blasting layer thickness (TH), total charge (TC), concentration ratio (CR), charge structure (CS) and cut holes maximum charge (CHC) were considered to estimate maximum rock size (MRS) for representing rock size distribution. The performances of six hybrid models were evaluated using statistical indices, regression analysis, error analysis and Taylor diagram. The results indicated that the proposed LMAOS-RF model is the best model to explainrelationship between the considered parameters and MRS. Finally, the results of sensitivity analysis demonstrated that TH and SPH are the greatest positive and negative parameter for predicting MRS. Therefore, this paper provides an accurate guidance for field engineers to optimize blasting design to reduce large block rate and further simplify tunneling. • Development of a novel hybrid RF model for predicting MRS after tunnel blasting. • Smooth blasting parameters, explosive parameters and rock mass parameters were used to predict MRS. • The LMAOS-RF model has the best performance for predicting MRS among all hybrid models. [ABSTRACT FROM AUTHOR]