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2D image-based 3D shape retrieval (2D-to-3D) aims at searching the corresponding 3D shapes (unlabeled) when given a 2D image (labeled), which is a fundamental task in computer vision and has gained a surge of attention in recent years. However, extensive prior works are limited by two settings, 1) reducing domain discrepancy while ignoring the 3D shape style, 2) 3D shapes are simply and brutally pseudo-annotated by the 2D image-supervised classifier, neglecting the structure information underlying the 3D shape domain. To remedy these issues, we propose a feature transformation framework with selective pseudo-labeling (FTSPL) for 2D-to-3D task. Specifically, we first employ CNNs to produce both 2D image and 3D shape (described as multiple views) features, then we force the inter-domain centroid alignment class-wisely to reduce the overall domain discrepancy. In addition to this, we further exploit the intra-category attribute variation (covariance) of 3D shape features to transform the 2D image features. By doing so, we can equip 2D features with 3D shape style. Since the centroid and covariance estimation of 3D shape features require accurate label predictions, we put forward a selective pseudo-labeling module, which can assign reliable pseudo-labels for 3D shapes via nearest category centroid and cluster analysis, respectively, while preserving the structure information of 3D shapes. Comprehensive experiments validate that our model surpasses the state-of-the-arts on standard 2D-to-3D benchmarks (MI3DOR and MI3DOR-2). [ABSTRACT FROM AUTHOR]

To diminish the performance degradation of coprime array beamforming arising from sensor gain and phase uncertainties, we propose a robust beamformer based on covariance matrix modification with augmented instrumental sensors. Initially, the received array data are split into two subarrays. Utilizing the instrumental sensors, we estimate the gain-phase errors of these two subarrays and then recombine them. Subsequently, error compensation is implemented to calibrate the received covariance matrix into a Toeplitz matrix relevant to the coprime array structure, in which the holes need to be further filled by means of some matrix completion operation. Then, the above covariance matrix modification is integrated into the classical beamforming procedure including MUSIC decomposition, spectral peak searching, power estimation, INCM (Interference-plus-Noise Covariance Matrix) reconstruction, thus yielding the final beamformer weight vector. Both theoretical analysis and simulations demonstrate that this method not only can accurately estimate the gain and phase errors, but also can effectively improve the beamformer's output SINR (i.e., the robustness is enhanced), which presents the proposed beamformer with vast potentials in practical sparse-array involved applications. • The designed beamformer can improve the robustness of a coprime array under gain-phase error. • Gain-phase error calibration via setting four instrumental sensors ahead of the coprime array. • Enlarging the continuous range of virtual array and performing matrix completion. [ABSTRACT FROM AUTHOR]

Objective: Hox transcript antisense intergenic RNA (HOTAIR), a lncRNA, functions as a critical regulator in cancer development. A plenty of case–control studies were conducted to assess the actual relationship of HOTAIR gene generic variants on cancer susceptibility, yet conflicting conclusions remain. Herein, we carried out this up-to-date meta-analysis to get a better understanding of such relationship by incorporating all eligible case–control studies. Materials and methods: Six widely investigated polymorphisms were included in this meta-analysis: rs920778, rs4759314, rs7958904, rs874945, rs1899663, and rs12826786. We retrieved relevant studies from databases PubMed, EMBASE, Medline, CNKI and Wanfang update to June 2020. We applied odds ratios (ORs) and 95% confidence intervals (CIs) to estimate the relationship strengths. Results: Our findings indicate that rs920778, rs4759314, rs874945, rs12826786 polymorphism significantly increased with susceptibility to overall cancer. However, rs7958904, rs1899663 under any five genetic models could not impact susceptibility to overall cancer. Furthermore, altered cancer risk was detected when the data were stratified by cancer type, ethnicity, the source of controls, and HWE in all the SNPs. Conclusions: These findings of the meta-analysis suggest that HOTAIR polymorphisms may predispose to cancer susceptibility. [ABSTRACT FROM AUTHOR]

This paper presents a fabric tensor-based bounding surface model accounting for anisotropic behaviour (e.g. the dependency of peak strength on loading direction and non-coaxial deformation) of granular materials. This model is developed based on a well-calibrated isotropic bounding surface model. The yield surface is modified by incorporating the back stress which is proportional to a contact normal-based fabric tensor for characterising fabric anisotropy. The evolution law of the fabric tensor, which is dependent on both rates of the stress ratio and the plastic strain, rules that the material fabric tends to align with the loading direction and evolves towards a unique critical state fabric tensor under monotonic shearing. The incorporation of the evolution law leads to a rotational hardening of the yield surface. The anisotropic critical state is assumed to be independent of the initial values of void ratio and fabric tensor. The critical state fabric tensor has the same intermediate stress ratio (i.e. b value) and principal directions as the critical state stress tensor. A non-associated flow rule in the deviatoric plane is adopted, which is able to predict the non-coaxial flow naturally. The stress–strain relation and fabric evolution of model predictions show a satisfactory agreement with DEM simulation results under monotonic shearing with different loading directions. The model is also validated by comparing with laboratory test results of Leighton Buzzard sand and Toyoura sand under various loading paths. The comparison results demonstrate encouraging applicability of the model for predicting the anisotropic behaviour of granular materials. [ABSTRACT FROM AUTHOR]

Calculation of repulsive force between clay particles is important for discrete element simulations of clays. This paper discusses the repulsive forces between two clay particles on the basis of the model in which two identical plates with finite length are symmetrically placed about a mid-plane. It is proven that the electrical repulsion calculated by the method commonly adopted in the literature is actually the osmotic repulsion, which only considers the contribution from excess osmotic pressure but ignores the contribution from Maxwell’s stress. A formula, which includes not only potential itself but potential gradient terms, is proposed to determine the total repulsive force between two clay particles. Finally, numerical calculations show that the errors due to neglecting the potential gradient terms can be up to over 25%. [ABSTRACT FROM AUTHOR]

Retrieving 3D shapes with 2D images has become a popular research area nowadays, and a great deal of work has been devoted to reducing the discrepancy between 3D shapes and 2D images to improve retrieval performance. However, most approaches ignore the semantic information and decision boundaries of the two domains, and cannot achieve both domain alignment and category alignment in one module. In this paper, a novel Collaborative Distribution Alignment (CDA) model is developed to address the above existing challenges. Specifically, we first adopt a dual-stream CNN, following a similarity guided constraint module, to generate discriminative embeddings for input 2D images and 3D shapes (described as multiple views). Subsequently, we explicitly introduce a joint domain-class alignment module to dynamically learn a class-discriminative and domain-agnostic feature space, which can narrow the distance between 2D image and 3D shape instances of the same underlying category, while pushing apart the instances from different categories. Furthermore, we apply a decision boundary refinement module to avoid generating class-ambiguity embeddings by dynamically adjusting inconsistencies between two discriminators. Extensive experiments and evaluations on two challenging benchmarks, MI3DOR and MI3DOR-2, demonstrate the superiority of the proposed CDA method for 2D image-based 3D shape retrieval task. [ABSTRACT FROM AUTHOR]

The article discusses the cloud system developed for mobile medical services for the provision of the traditional Chinese medicine practice of acupuncture to sample patients at the Lukang Branch of the Changhua Christian Hospital (CCH) in Taiwan. Topics discussed include the website set up for database information sharing, the Android mobile devices with the PC cloud server and the need for medical cloud system compatibility with the different operating systems such as Android or iOs.

This paper presents a theoretical study on a hybrid fabric evolution law for modelling anisotropic behaviour of granular media. In the hybrid evolution law, the rate of a contact normal-based fabric tensor is related to the rates of both stress ratio tensor and plastic strain. Assumptions and principles that were adopted for the development of the fabric evolution law are presented and discussed at first. Its accuracy is then examined by comparing with discrete element modelling (DEM) results under proportional loading and experimental data under complex loading and unloading processes. It is found that fabric evolution at low stress ratios is closely related to the stress-rate driven term of the hybrid law, while the strain-rate driven term dominates at high stress ratios. The hybrid evolution law satisfies the uniqueness requirement of fabric at the critical state by introducing an 'attractor' concept. Overall, fabric evolutions predicted by the hybrid law show a close agreement with DEM simulation results and experimental data. [ABSTRACT FROM AUTHOR]

The pores of pervious concrete pavement will be clogged by sediment carried by rainwater runoff and atmospheric deposition on the pavement in the course of using, thus reducing the permeability of pavement. It is necessary to adopt effective maintenance measures to keep the permeability of the pavement. In this study, an improved single ring infiltrometer is used to measure the permeability of a newly constructed pervious pavement. In order to study the deterioration process of the pavement permeability under periodic clogging maintenance conditions, four different gradations of clogging materials and eight different maintenance methods were used for 32 test cases. Different maintenance methods are designed to find the best combination, including different pressure wash, sweep + vacuum and pressure wash + vacuum. The study shows when the pressure wash is between 5 and 20Mpa, the maintenance effect has little difference, and the combination of pressure wash and vacuum suction has the best maintenance effect. • The permeability of pervious pavement will completely be lost after periodic clogging. • Periodic maintenance can extend the service life of pervious pavement. • Pressure wash + vacuum has the best maintenance effect. • A fitted relationship is developed to evaluate the remaining permeability after certain periodic maintenances. [ABSTRACT FROM AUTHOR]

Herein, we proposed a novel bioenzyme-free dual-mode sensing strategy for the rapid and accurate monitoring of organophosphorus pesticides (OPs) by preparing tris(2,2′-bipyridyl) ruthenium(II) (Ru(bpy) 3 2+) encapsulated with UiO-66-NH 2 MOFs as nanozyme (Ru@Zr-MOFs). The as-prepared Ru@Zr-MOFs nanozyme not only exhibits superior peroxidase-like activity which can catalyze O-phenylenediamine (OPD) oxidation to generate yellow 2,3-diaminophenazinc, but also exhibits dual-fluorescence feature (at 442 and 612 nm respectively) and specific interaction capacity with OPs. However, in the existence of OPs, the peroxidase-like activity of Ru@Zr-MOFs nanozyme is restricted and the oxidation process of OPD is stopped; meanwhile, the fluorescence of Ru@Zr-MOFs at 442 nm increases rapidly (< 10 s) while that at 612 nm is apathetic, thus a colorimetric and ratiometric fluorescent sensing strategy was first designed to detect OPs by using glyphosate (Gly) as a typical model of OPs. Then, in consideration of the benefits of smartphone which can make the sensing process more convenient, stable, rapid and sensitive feedback, a smartphone coupled with hydrogel detection platform was proposed also for OPs determination. In addition, the designed sensing strategy offers superior selectivity, stability and real application capabilities. It's thus expected the as-designed Ru@Zr-MOFs nanozyme based dual-mode sensing strategy possesses important real application for the low-cost, rapid, sensitive and accurate determination of OPs. • The successful preparation of Ru@Zr-MOFs nanozyme. • Ru@Zr-MOFs exhibits high peroxidase-like activity and dual-fluorescence as well as specific interaction ability with OPs. • The first proposition of bioenzyme-free dual-mode (colorimetry and fluorescent) sensing strategy for OPs. • Considerably short detection time, especially < 10 s for the ratiometric fluorescence sensing. • The proposed sensing method offer satisfactory sensing performances. [ABSTRACT FROM AUTHOR]

This research presents the implementation of artificial intelligence (AI) for classification of frogs in symmetry of the bioacoustics spectral by using the feedforward neural network approach (FNNA) and support vector machine (SVM). Recently, the symmetry concept has been applied in physics, and in mathematics to help make mathematical models tractable to achieve the best learning performance. Owing to the symmetry of the bioacoustics spectral, feature extraction can be achieved by integrating the techniques of Mel-scale frequency cepstral coefficient (MFCC) and mentioned machine learning algorithms, such as SVM, neural network, and so on. At the beginning, the raw data information for our experiment is taken from a website which collects many kinds of frog sounds. This in fact saves us collecting the raw data by using a digital signal processing technique. The generally proposed system detects bioacoustic features by using the microphone sensor to record the sounds of different frogs. The data acquisition system uses an embedded controller and a dynamic signal module for making high-accuracy measurements. With regard to bioacoustic features, they are filtered through the MFCC algorithm. As the filtering process is finished, all values from ceptrum signals are collected to form the datasets. For classification and identification of frogs, we adopt the multi-layer FNNA algorithm in machine learning and the results are compared with those obtained by the SVM method at the same time. Additionally, two optimizer functions in neural network include: scaled conjugate gradient (SCG) and gradient descent adaptive learning rate (GDA). Both optimization methods are used to evaluate the classification results from the feature datasets in model training. Also, calculation results from the general central processing unit (CPU) and Nvidia graphics processing unit (GPU) processors are evaluated and discussed. The effectiveness of the experimental system on the filtered feature datasets is classified by using the FNNA and the SVM scheme. The expected experimental results of the identification with respect to different symmetry bioacoustic features of fifteen frogs are obtained and finally distinguished. [ABSTRACT FROM AUTHOR]

The experiment investigated the immunomodulatory effects of APS on the avian infectious bronchitis attenuated vaccine, aiming to explore the potential application of APS as a vaccine adjuvant. A total of 120 fourteen-day-old chickens were randomly divided into three groups with four replicates per group and one chickens per replicate, designated as the APS+H120 co-immunization group, the H120 vaccine group, and the PBS negative control group. All groups of chickens were immunized three times at two-week intervals, with each nasal inoculation consisting of 100 μL per chicken. Fourteen days after the final immunization, the chickens were intranasally challenged with the infectious bronchitis virus strain M41. The clinical symptoms of chickens were observed, and the amount of lung and liver virus was detected. The results showed that compared with the H120 vaccine group, the APS+H120 vaccine combined immunization can induce the production of IBV specific IgG and sIgA in 14-day-old chickens, effectively protecting them against the attack of allogenic strains, and the survival rate of laying hens was 100%. The APS+H120 group did not show the typical clinical symptoms of avian infectious bronchitis, and the production performance of laying hens was not affected. The study indicates that APS has a promoting effect on the immune response of chickens to the infectious bronchitis H120 attenuated vaccine. [ABSTRACT FROM AUTHOR]

This paper presents unified solutions for elastic–plastic expansion analysis of a cylindrical or spherical cavity in an infinite medium, adopting a flow theory of strain gradient plasticity. Previous cavity expansion analyses incorporating strain gradient effects have mostly focused on explaining the strain localization phenomenon and/or size effects during infinitesimal expansions. This paper is however concerned with the size-dependent behaviour of a cavity during finite quasi-static expansions. To account for the non-local influence of underlying microstructures to the macroscopic behaviour of granular materials, the conventional Mohr–Coulomb yield criterion is modified by including a second-order strain gradient. Thus the quasi-static cavity expansion problem is converted into a second-order ordinary differential equation system. In the continuous cavity expansion analysis, the resulting governing equations are solved numerically with Cauchy boundary conditions by simple iterations. Furthermore, a simplified method without iterations is proposed for calculating the size-dependent limit pressure of a cavity expanding to a given final radius. By neglecting the elastic strain increments in the plastic zone, approximate analytical size-dependent solutions are also derived. It is shown that the strain gradient effect mainly concentrates in a close vicinity of the inner cavity. Evident size-strengthening effects associated with the sand particle size and the cavity radius in the localized deformation zone is captured by the newly developed solutions presented in this paper. The strain gradient effect will vanish when the intrinsic material length is negligible compared to the instantaneous cavity size, and then the conventional elastic perfectly-plastic solutions can be recovered exactly. The present solutions can provide a theoretical method for modeling the size effect that is often observed in small-sized sand-structure interaction problems. [ABSTRACT FROM AUTHOR]

This paper presents numerical applications of a non-coaxial soil model, in which an anisotropic yield criterion is incorporated, to analyze two-dimensional strip-footing problems. Semi-analytical solutions of the bearing capacity for a strip footing that rests on anisotropic, weightless, cohesive-frictional soils are developed based on the slip line method. The degrees of influences of soil anisotropy and non-coaxiality on the bearing capacity of the strip footing are examined. From the viewpoint of strength and stiffness, it is necessary to incorporate both the strength anisotropy and non-coaxiality into numerical simulations and practical designs of geotechnical problems. [ABSTRACT FROM AUTHOR]

The permeability coefficient is the foundation of evaluating the clogging and maintenance. In this study, 384 field tests were carried out on 9 positions using single-ring and double-ring permeameters with different diameters. Both falling head and constant head methods were evaluated. At the same time, core samples were drilled from the 9 test positions, and their permeability coefficients were measured in the laboratory. The results show that there is a good correlation between falling head method and constant head method, both of them can be used to measure in-situ permeability coefficient of pervious pavement. Although the double-ring method can reduce the transverse seepage inside the pavement, the effect of double-ring permeameters with different cylinder diameters is different, and permeameters with larger cylinder diameters are better. For sites with permeability greater than 2 mm/s, it is not recommended to use permeameters with small cylinder diameters.. [ABSTRACT FROM AUTHOR]

This paper proposes a novel method to solve signomial discrete programming (SDP) problems frequently occurring in engineering design. Various signomial terms are first convexified following different strategies. The original SDP program is then converted into a convex integer program solvable by commercialized packages to obtain globally optimal solutions. Compared with current SDP methods, the proposed method is guaranteed to converge to a global optimum, is computationally more efficient, and is capable of treating zero boundary problems. Numerical examples are presented to demonstrate the usefulness of the proposed method in engineering design. [ABSTRACT FROM AUTHOR]

• The anti-clogging performance of various permeable structures is studied by numerical method. • The anti-clogging mechanism of double-layer permeable pavement structure are studied. • A tubular double-layer permeable structure with good anti-clogging performance is developed. Based on numerical simulation methods, the anti-clogging performance of various pervious pavement structures were investigated. Different pavement structure models were built to analyze the effects of different pervious structures, top layer thicknesses and top aggregate gradations on the anti-clogging performance. The results shown that compared with single-layer structure, the double-layer pervious structure has better anti-clogging performance and maintenance efficiency. The most serious clogging of double-layer pervious structure can be hold within 3 mm of the superficial layer where the clogging particles can more easily be cleaned out. Smaller top layer thickness lead to a better anti-clogging performance and maintenance efficiency. And the top layer aggregate size should be selected only considering particle transport or shielding effect, based on the gradation of local clogging particles. In addition, based on the above findings, a new double-layer pervious structure with excellent anti-clogging performance has been developed, including a number of parallel vertical variable diameter tubular channels, the diameter of the upper layer is smaller than that of the lower layer. [ABSTRACT FROM AUTHOR]

Abstract In this paper, the effects of the intermediate stress ratio, i.e., b -value (b = (σ 2 − σ 3)/(σ 1 − σ 3)), on the contact normal-based fabric evolution of granular material, are incorporated into an extant hybrid fabric evolution law. The new evolution law is validated by Discrete Element Method (DEM) simulation results under monotonic shearing with different b -values. Predictions of the proposed generalized fabric evolution law agree well with the DEM simulation results. This evolution law can be widely used for constitutive modelling of granular materials, considering the effects of b -value in a general geomechanical three-dimensional stress space. [ABSTRACT FROM AUTHOR]

Monodisperse surface-charged submicron polystyrene particles were designed, synthesized, and blended into polysulfone (PSF) support layer to prepare forward osmosis (FO) membrane with high performance. The membrane incorporated with particles were characterized with respect to morphology, porosity, and internal osmotic pressure (IOP). Results showed that the polymer particles not only increased the hydrophilicity and porosity of support layer, but also generated considerable IOP, which helped markedly decreasing the structure parameter from 1550 to 670 μm. The measured mass transfer parameters further confirmed the beneficial effects of the surface-charged submicron polymer particles on the performance of FO membrane. For instance, the water permeability coefficient (5.37 L m −2  h −1  bar −1 ) and water flux (49.7 L m −2  h −1 ) of the FO membrane incorporated with 5 wt% particles were almost twice as much as that of FO membrane without incorporation. This study suggests that monodisperse surface-charged submicron polymer particles are potential modifiers for improving the performance of FO membranes. [ABSTRACT FROM AUTHOR]

Abstract: A unified failure envelope for hybrid steel-polypropylene fibre reinforced concrete (HFRC) subjected to true triaxial compression is presented in this paper, aiming to predict the ultimate strength of HFRC under multiaxial compressions. The failure envelope based on a five-parameter failure criterion was developed which accounts for the presence of hybrid fibres. The model parameters were calibrated through true triaxial compression tests. The results showed that the steel fibres mainly contribute to the composite’s triaxial strength that was observed to improve significantly when both the volume fractions and aspect ratios of steel fibre were increased. On the other hand, the polypropylene fibres were found to have considerable effect on improving the tensile meridian rather than compressive meridian. Furthermore, the developed model was evaluated against existing experimental results of both plain concrete and fibre reinforced concrete. It was observed that, with the removal of fibres, the developed model can reverse to the model of plain concrete, and the prediction yields a close and mostly conservative approximation of the ultimate strength. [Copyright &y& Elsevier]

Abstract: X-ray photoelectron spectroscopy was used to investigate the characteristics and evolution of sulfur (S) in mixtures of bituminous coal and sewage sludge (SS) and their chars during isothermal combustion. Five groups of mixtures with SS content of 0%, 10%, 20%, 30% and 100%, were examined at different burn-off ratios (¿) of 0, 30%, 50%, 70% and 100%. The S in the coal mainly exist as the forms of mercaptan (S1), sulfide (S2), thiophene (S3), sulfoxide (S4), sulfone (S5) and sulfate (S6). During the coal combustion process, the content of S1 and S2 decreased, while that of S3 and S5 increased in the early stage and decreased in the late stage. The S4 content increased throughout the entire process of combustion. Small amount of S6 was detected, showing a fluctuated pattern. The trend of S1, S2, S5 and S6 in SS was alike with that in coal, whereas S4 decreased at the end of combustion. The changing process of S3 in SS was opposite to that of coal, while the composition of S in the mixtures resulted from the mixing of coal and SS. The transformation of each functional group during co-combustion were correlated with their transformation characteristics during the mono-combustion of coal and SS, and no obvious interaction was observed, which demonstrated that the coal-origin and SS-origin sulfur in mixtures kept their own characteristics in the combustion. SS may accumulate on the solid surface as ¿ increase, resulting its significant influence on the evolution of each form of S. When ¿ was low, most of the S-contained functional groups presented the characteristics of coal. The percentage of coal-origin functional groups declined as ¿ increased. The transforming trends of most functional groups were similar with that of SS when ¿ reached 30%. [Copyright &y& Elsevier]

In this study, a self-monitoring polymer geobelt manufactured via 3D printing technology is proposed; conductive acrylonitrile–butadienestyrene (ABS) was embedded directly into non-conductive polylactic-acid (PLA) in the form of a conductive wire. The self-monitoring polymer geobelt made of PLA and conductive ABS presented good self-perception characteristics and recoverability; the higher the number of internal conductive wires arranged in a longitudinal layout, the more accurate the results. The relationship between the resistance and the tensile stress after being normalized at the ends of the geobelt can be fitted using the parabola f = A + Br + Cr2, and the strain of the smart geobelt ranged from 2.1 to 10%. • A sealed self-monitoring polymer geobelt is proposed. • Geobelt is made up by conductive core and nonconductive coating material. • 3D printing reduces the time of specimen preparing and improves the repeatability. Due to the rise of smart city construction in recent years, there is a growing demand for materials that can both improve the mechanical properties of structures and carry out health monitoring and risk warning. In this paper, a self-monitoring polymer geobelt manufactured by 3D printing technology is proposed, which can embed conductive ABS material directly into non-conductive PLA material as conductive wire. This integrated resistance geobelt solves the problem of sensor contact to the outside of the grid and water which is easy to fall off and the test results are inaccurate. In this study, a series of tests were performed to study the development and laboratory evaluation of a tensoresistivity geobelts and conclusions were drawn as follows: The self-monitoring polymer geobelt made with PLA and conductive ABS showed good self-perception characteristics and recoverability, and the more the number of longitudinal layout of internal conductive wires, the more accurate the results showed. The relationship between resistance and tensile stress after normalized at ends of the geobelt can be fitted by parabola f = A + Br + Cr2, and the strain of smart geobelt ranges from 2.1 to 10%. [ABSTRACT FROM AUTHOR]

Dissolved oxygen concentration in water is one of the critical indicators for measuring the self-purification ability of water. The process of re-oxygenation directly affects the migration, diffusion, and degradation of organic pollutants in water as well as the self-purification process of an entire body of water. To solve the problem of water pollution and restore the ecological and social functions of the urban stream has become the key to ensure the sustainable development of the city. Many overflow weirs have been built along urban streams in northern China to retain landscape water. This study attempts to use a numerical simulation method to study the factors affecting the re-oxygenation process of urban streams by overflow weirs. Combined with flow regime analysis, the re-oxygenation efficiency of stepped overflow weirs for free surface flow under different influence factors such as unit discharge, number of steps and slope of overflow weir were compared. The results show that the re-oxygenation efficiency of a nappe flow is higher than that of a skimming flow or a transition flow. Re-oxygenation efficiency is sensitive to changes in unit discharge and reaches its peak value when the unit discharge of an inlet is about 0.06 m2/s. A comparison analysis of our present experimental simulation data shows that the slope for stepped overflow weirs for optimum re-oxygenation efficiency is 51.3°. For small flow conditions (q < 0.10 m2/s), stepped overflow weirs with fewer steps and greater weir height contribute to higher re-oxygenation efficiency. For large flow conditions (q > 0.10 m2/s), unit discharge, number of steps, and total weir height have little effect on the re-oxygenation efficiency of stepped overflow weirs. Image 106785 • Numerical simulation combining the VOF method, species transport model and UDF was conducted. • Nappe flow regime provides a greater E 20 than that of the other flow regimes. • The slope for stepped overflow weirs for optimum re-oxygenation efficiency is 51.3°. • Stepped flow weirs with fewer steps and a greater height produce greater E 20 for q < 0.10 m2/s. [ABSTRACT FROM AUTHOR]

In this paper, to the best of our knowledge, we replied to the comment on our published article "Numerical study on pore clogging mechanism in pervious pavements" (Zhang et al., 2018). First, we solved the problem about inappropriate descriptions to the cited papers and some errors in equations. Second, we explained the relationship between fluid cell size in CFD (computational fluid dynamics) and particle size in DEM (discrete element method) in our CFD-DEM model, and we verified the reliability and accuracy of our CFD-DEM model using single-particle sedimentation case. It demonstrated that the CFD-DEM method used in our study was acceptable. [ABSTRACT FROM AUTHOR]