The influence of inter-band rock on rib spalling in longwall panel with large mining height

In order to improve rib stability,failure criteria and instability mode of a thick coal seam with inter-band rock layer are analysed in this study.A three-dimensional mechanical model is established for the rib by considering the rock layer.A safety factor is defined foy the rib,and it is observed that the safety factor exhibits a positive correlation with the thickness and strength of the inter-band rock.A calculation method for determining critical parameters of the rock layer is presented to ensure the rib stability.It is revealed that incomplete propagation of the fracture at the hard rock constitutes a fundamental prerequisite for ensuring the rib stability.The influence of the position of the inter-band rock in the coal seam on failure mechanism of the rib was thoroughly investigated by developing a series of physical models for the rib at the face area.The best position for the inter-band rock in the coal seam is at a height of 1.5 m away from the roof line,which tends to provide a good stability state for the rib.For different inter-band rock positions,two ways of controlling rib by increasing supports stiffness and flexible grouting reinforcement are proposed.

The effect of topographic density variations on the geoid and orthometric heights in Hong Kong

Utilizing the adopted average topographic density of 2670 kg/m^(3)in the reduction of gravity anomalies introduces errors attributed to topographic density variations,which consequently affect geoid modeling accuracy.Furthermore,the mean gravity along the plumbline within the topography in the definition of Helmert orthometric heights is computed approximately by applying the Poincar e-Prey gravity reduction where the topographic density variations are disregarded.The Helmert orthometric heights of benchmarks are then affected by errors.These errors could be random or systematic depending on the specific geological setting of the region where the leveling network is physically established and/or the geoid model is determined.An example of systematic errors in orthometric heights can be given for large regions characterized by sediment or volcanic deposits,the density of which is substantially lower than the adopted topographic density used in Helmert's definition of heights.The same applies to geoid modeling errors.In this study,we investigate these errors in the Hong Kong territory,where topographic density is about 20%lower than the density of 2670 kg/m^(3).We use the digital rock density model to estimate the effect of topographic density variations on the geoid and orthometric heights.Our results show that this effect on the geoid and Helmert orthometric heights reach maxima of about 2.1 and 0.5 cm,respectively.Both results provide clear evidence that rock density models are essential in physical geodesy applications involving gravimetric geoid modeling and orthometric height determination despite some criticism that could be raised regarding the reliability of these density models.However,in regions dominated by sedimentary and igneous rocks,the geological information is essential in these applications because topographic densities are substantially lower than the average density of 2670 kg/m^(3),thus introducing large systematic errors in geoid and orthometric heights.

Exact and heuristic formulae to compute the geodetic height from the ellipse equation

The conversion of the cartesian coordinates of a point to its geodetic equivalent coordinates in reference to the geodetic ellipsoid is one of the main challenges in geodesy.The ellipse equation in the meridian plane significantly influences the value of the geodetic coordinates.This research analyzes this influence and how it can contribute to their solutions.The study investigates the mathematical relation between them and presents an exact formula relating to the geodetic height and the ellipse equation.In addition,a heuristic formula for the relation between the geodetic height and the ellipse equation is proposed,which is independent of the geodetic latitude and has a relative accuracy better than 99.9 %.The calculation is stable,and the cost is low.

Influence of pier height on the safety of trains running on high-speed railway bridges during earthquakes

Sudden earthquakes pose a threat to the running safety of trains on high-speed railway bridges,and the stiffness of piers is one of the factors affecting the dynamic response of train-track-bridge system.In this paper,a experiment of a train running on a high-speed railway bridge is performed based on a dynamic experiment system,and the corresponding numerical model is established.The reliability of the numerical model is verified by experiments.Then,the experiment and numerical data are analyzed to reveal the pier height effects on the running safety of trains on bridges.The results show that when the pier height changes,the frequency of the bridge below the 30 m pier height changes greater;the increase of pier height causes the transverse fundamental frequency of the bridge close to that of the train,and the shaking angle and lateral displacement of the train are the largest for bridge with 50 m pier,which increases the risk of derailment;with the pier height increases from 8 m to 50 m,the derailment coefficient obtained by numerical simulations increases by 75% on average,and the spectral intensity obtained by experiments increases by 120% on average,two indicators exhibit logarithmic variation.

BnaC03.BIN2 regulates plant height by affecting the main inflorescence length and first effective branch height in Brassica napus L.

Rapeseed(Brassica napus L.)is one of the main oil crops in the world,and increasing its yield is of great significance for ensuring the safety of edible oil.Presently,improving rapeseed plant architecture is an effective way to increase rapeseed yield with higher planting density.However,the regulatory mechanism of rapeseed plant architecture is poorly understood.In this study,a dwarf rapeseed mutant dwarf08(df08)is obtained by ethyl methane sulfonate(EMS)-mutagenesis.The decrease in plant height of df08 is mainly caused by the reduction in main inflorescence length and first effective branch height and controlled by a single semi-dominant gene.The hybrid plants(F1)show a semi-dwarf phenotype.Through map-based cloning and transgenic assay,we confirm that the nonsynonymous single nucleotide variant(SNV)(C to T)in BnaC03.BIN2,which is homologous with Arabidopsis(Arabidopsis thaliana)BIN2,is responsible for the dwarfism of df08.BnaC03.BIN2 interacts with BnaBZR1/BES1 and involves in brassinosteroids(BRs)signal transduction.Proline to Leucine substitution in 284(P284L)enhances the protein stability of BnaC03.bin2-D,disrupts BRs signal transduction and affects the expression of genes regulating cell division,leading to dwarfism of df08.This study provides a new insight for the mechanism of rapeseed plant height regulation and creates an elite germplasm that can be used for genetic improvement of rapeseed architecture.

A Multi-Baseline PolInSAR Forest Height Inversion Method Taking into Account the Model Ill-posed Problem

Affected by the insufficient information of single baseline observation data,the three-stage method assumes the Ground-to-Volume Ratio(GVR)to be zero so as to invert the vegetation height.However,this assumption introduces much biases into the parameter estimates which greatly limits the accuracy of the vegetation height inversion.Multi-baseline observation can provide redundant information and is helpful for the inversion of GVR.Nevertheless,the similar model parameter values in a multi-baseline model often lead to ill-posed problems and reduce the inversion accuracy of conventional algorithm.To this end,we propose a new step-by-step inversion method applied to the multi-baseline observations.Firstly,an adjustment inversion model is constructed by using multi-baseline volume scattering dominant polarization data,and the regularized estimates of model parameters are obtained by regularization method.Then,the reliable estimates of GVR are determined by the MSE(mean square error)analysis of each regularized parameter estimation.Secondly,the estimated GVR is used to extracts the pure volume coherence,and then the vegetation height parameter is inverted from the pure volume coherence by least squares estimation.The experimental results show that the new method can improve the vegetation height inversion result effectively.The inversion accuracy is improved by 26%with respect to the three-stage method and the conventional solution of multi-baseline.All of these have demonstrated the feasibility and effectiveness of the new method.

Factors influencing further vertebral height loss following percutaneous vertebroplasty in osteoporotic vertebral compression fractures:A 1-year follow-up study

BACKGROUND Osteoporotic vertebral compression fractures(OVCFs)contribute to back pain and functional limitations in older individuals,with percutaneous vertebroplasty(PVP)emerging as a minimally invasive treatment.However,further height loss post-PVP prompts investigation into contributing factors.AIM To investigate the factors associated with further height loss following PVP with cement augmentation in OVCF patients.METHODS A total of 200 OVCF patients who underwent successful PVP between January 2021 and December 2022 were included in this study.“Further height loss”during 1 year of follow-up in OVCF patients with bone edema was defined as a vertical height loss of≥4 mm.The study population was divided into two groups for analysis:The“No Further Height Loss group(n=179)”and the“Further Height Loss group(n=21).”RESULTS In comparing two distinct groups of patients,significant differences existed in bone mineral density(BMD),vertebral compression degree,prevalence of intravertebral cleft(IVF),type of bone cement used,and cement distribution patterns.Results from binary univariate regression analysis revealed that lower BMD,the presence of IVF,cleft distribution of bone cement,and higher vertebral compression degree were all significantly associated with further height loss.Notably,the use of mineralized collagen modified-poly(methyl methacrylate)bone cement was associated with a significant reduction in the risk of further height loss.In multivariate regression analysis,lower BMD and the presence of IVF remained significantly associated with further height loss.CONCLUSION Further height loss following PVP in OVCF patients is influenced by a complex interplay of factors,especially lower BMD and the presence of IVF.These findings underscore the importance of assessing and managing these factors when addressing height loss following PVP in OVCF patients.

A Fine-grained Building Height Control Method for Heritage Areas from the Perspective of Visual Integrity

This study proposes a refined methodology for controlling building heights in heritage areas.In order to protect the visual integrity of the heritage area,buildings should not obstruct the view from important site points and viewpoints to the periphery.By calculating the building height thresholds that buildings should not obscure the view from each viewpoint,the results of which are weighted and superimposed,and the values are extracted to each building unit as a refined building height control guideline.This study takes the Zhoukoudian area as a case study,applies the refined building height control criterion to the Zhoukoudian Site,and relies on this refined criterion to assess the visual integrity of the Zhoukoudian area,so as to realize the scientific planning and monitoring of the Zhoukoudian area.The refined building height control method can be applied to building height planning and visual landscape protection in large heritage areas.

An approach to estimate tree height using PolInSAR data constructed by the Sentinel-1 dual-pol SAR data and RVoG model

We estimate tree heights using polarimetric interferometric synthetic aperture radar(PolInSAR)data constructed by the dual-polarization(dual-pol)SAR data and random volume over the ground(RVoG)model.Considering the Sentinel-1 SAR dual-pol(SVV,vertically transmitted and vertically received and SVH,vertically transmitted and horizontally received)configuration,one notes that S_(HH),the horizontally transmitted and horizontally received scattering element,is unavailable.The S_(HH)data were constructed using the SVH data,and polarimetric SAR(PolSAR)data were obtained.The proposed approach was first verified in simulation with satisfactory results.It was next applied to construct PolInSAR data by a pair of dual-pol Sentinel-1A data at Duke Forest,North Carolina,USA.According to local observations and forest descriptions,the range of estimated tree heights was overall reasonable.Comparing the heights with the ICESat-2 tree heights at 23 sampling locations,relative errors of 5 points were within±30%.Errors of 8 points ranged from 30%to 40%,but errors of the remaining 10 points were>40%.The results should be encouraged as error reduction is possible.For instance,the construction of PolSAR data should not be limited to using SVH,and a combination of SVH and SVV should be explored.Also,an ensemble of tree heights derived from multiple PolInSAR data can be considered since tree heights do not vary much with time frame in months or one season.

Study of the ability of SWOT to detect sea surface height changes caused by internal solitary waves

Surface Water and Ocean Topography(SWOT)is a next-generation radar altimeter that offers high resolution,wide swath,imaging capabilities.It has provided free public data worldwide since December 2023.This paper aims to preliminarily analyze the detection capabilities of the Ka-band radar interferometer(KaRIn)and Nadir altimeter(NALT),which are carried out by SWOT for internal solitary waves(ISWs),and to gather other remote sensing images to validate SWOT observations.KaRIn effectively detects ISW surface features and generates surface height variation maps reflecting the modulations induced by ISWs.However,its swath width does not completely cover the entire wave packet,and the resolution of L2/L3 level products(about 2 km)cannot be used to identify ISWs with smaller wavelengths.Additionally,significant wave height(SWH)images exhibit blocky structures that are not suitable for ISW studies;sea surface height anomaly(SSHA)images display systematic leftright banding.We optimize this imbalance using detrending methods;however,more precise treatment should commence with L1-level data.Quantitative analysis based on L3-level SSHA data indicates that the average SSHA variation induced by ISWs ranges from 10 cm to 20 cm.NALTs disturbed by ISWs record unusually elevated SWH and SSHA values,rendering the data unsuitable for analysis and necessitating targeted corrections in future retracking algorithms.For the normalized radar cross section,Ku-band and four-parameter maximum likelihood estimation retracking demonstrated greater sensitivity to minor changes in the sea surface,making them more suitable for ISW detection.In conclusion,SWOT demonstrates outstanding capabilities in ISW detection,significantly advancing research on the modulation of the sea surface by ISWs and remote sensing imaging mechanisms.

Beyond Gender Perspectives:A More Comprehensive Examination of Yang Yi’s Translation of Wuthering Heights

The renowned translator Yang Yi passed away in 2023.Many scholars argue that,influenced by their biological gender,female translators often employ translation methods in adherence to feminist translation or reflect characteristics typical of female translators.This study examines the translation of Wuthering Heights by Yang Yi,focusing on whether there is a definite influence of gender on translator behavior.While existing literature primarily analyzes Yang Yi’s work through a feminist lens,this research takes a broader approach.By considering the translator’s social background and translation practice,this paper challenges the assumption that her work strictly aligns with feminist translation theories.Instead,this study emphasizes the importance of considering diverse factors when interpreting translated works,moving beyond a singular gender-based standpoint.

Study of the Effects of Glucocorticoid on Growth and Adult Final Height in Children with Primary Nephrotic Syndrome

Objective: To analyze the epidemiological characteristics of growth, as well as factors associated with growth retardation in children with primary nephrotic syndrome (PNS), and to investigate the effect of glucocorticoid (GC) use duration on growth retardation in these children. Methods: Clinical and laboratory data of 353 PNS children treated at our hospital from July 2014 to June 2015 were collected through the medical record management system. Height, weight, and GC usage were recorded. Follow-up assessments were conducted in August 2022 for the original group, recording height, weight, and GC usage. Height and weight were evaluated using standard deviation scores (SDS). Categorical data were analyzed using chi-square test while continuous measurement data were analyzed using t-test or rank-sum test. Linear regression was used to assess the association between two single independent variables, and logistic regression analysis was used to screen for risk factors related to growth retardation in children with PNS. Results: Among the 353 PNS children enrolled in this study, male-to-female ratio of 2.64:1 (256 males vs 97 females). A total of 119 children exhibited growth retardation, incidence rate of 33.71%. The duration of GC usage among those with growth retardation was significantly longer compared to those without it (762.81 ± 934.50 days vs 263.77 ± 420.49 days;p Conclusion: PNS children treated with GC have a high incidence of growth retardation, and a high proportion of short stature in adulthood, especially in children with growth retardation in childhood, most of them have short stature after grown up. Time of GC usage is a risk factor for growth retardation in children with PNS.

Impacts of bird abundance, activity height and light intensity on the number of birds captured by mist netting

To understand better the impact on mist net capture rates of the activity height of birds, light intensity, bird richness and abundance, we compared data from mist nets and point counts at the Jianfengling Forest Area, Hainan Island. Mist-nets were operated for a total of 7135 net-hours. A total of 587 individuals of 45 bird species were captured. The total mean capture rate was 8.6 ± 10.4 per 100 net-hours. A total of 4932 individuals of 107 bird species were recorded by visual observation alone and 7616 individuals of 120 species were recorded in a visual and aural combination. The Grey-cheeked Fulvetta (Alcippe morrisonia) was the most abundant species, accounting for 38.7% of total captures, 27.9% of visual observations and 22.2% of visual + aural observations. The capture number was correlated with the number observed. Thirty-one species were more likely to be captured than observed. Canopy species, such as members of the Corvidae and Dicruridae, were seldom captured. For all ground feeding species, the capture number was greater than that of observation. Some cryptic species, such as the Lesser Wren Babbler (Napothera epilepidota), Spotnecked Babbler (Stachyris striolata) and Cuckoo Owl (Glaucidium cuculoides) also had a higher relative capture rate than that of observations. There was a significant relationship between light intensity and the number of birds captured.

Radar Quantitative Precipitation Estimation Based on the Gated Recurrent Unit Neural Network and Echo-Top Data

The Gated Recurrent Unit(GRU) neural network has great potential in estimating and predicting a variable. In addition to radar reflectivity(Z), radar echo-top height(ET) is also a good indicator of rainfall rate(R). In this study, we propose a new method, GRU_Z-ET, by introducing Z and ET as two independent variables into the GRU neural network to conduct the quantitative single-polarization radar precipitation estimation. The performance of GRU_Z-ET is compared with that of the other three methods in three heavy rainfall cases in China during 2018, namely, the traditional Z-R relationship(Z=300R1.4), the optimal Z-R relationship(Z=79R1.68) and the GRU neural network with only Z as the independent input variable(GRU_Z). The results indicate that the GRU_Z-ET performs the best, while the traditional Z-R relationship performs the worst. The performances of the rest two methods are similar.To further evaluate the performance of the GRU_Z-ET, 200 rainfall events with 21882 total samples during May–July of 2018 are used for statistical analysis. Results demonstrate that the spatial correlation coefficients, threat scores and probability of detection between the observed and estimated precipitation are the largest for the GRU_Z-ET and the smallest for the traditional Z-R relationship, and the root mean square error is just the opposite. In addition, these statistics of GRU_Z are similar to those of optimal Z-R relationship. Thus, it can be concluded that the performance of the GRU_ZET is the best in the four methods for the quantitative precipitation estimation.

Obtaining accurate measurements of the sea surface height from a GPS buoy

A dedicated GPS buoy is designed for calibration and validation(Cal/Val)of satellite altimeters since 2014.In order to evaluate the accuracy of the sea surface height(SSH)measured by the GPS buoy,twelve campaigns have been done within China sea area between 2014 and 2021.In six of these campaigns,two static Global Navigation Satellite System stations were installed at distances of<1 km and 19 km from the buoy to assess how the baseline length influenced the derived SSH from the buoy solutions.The GPS buoy data was processed using the GAMIT/GLOBK software+TRACK module and CSRS-PPP tool to achieve the SSH.The SSH was compared with conventionally tide gauge(TG)data to evaluate the accuracy of the buoy with the standard deviation of the height element.The results showed that the difference in the standard deviation of the SSH from the buoy and the TG was less than 16 mm.The SSHs processed with different ephemeris(Ultra-Rapid,Rapid,Final)were not significantly different.When the baseline length was 19 km,the SSH solution of the GPS buoy performed well,with standard bias of less than 26 mm between the heights measured by the buoy and TG,meaning that the buoy could be used for Cal/Val of altimeters.The bias between the Canadian Spatial Reference System-precise point positioning tool and the TRACK varied a lot,and some of them were over 130 mm.This deemed too high to be useful for Cal/Val of satellite altimeters.Moreover,the GPS buoy solutions processed by GAMIT/GLOBK software+TRACK module were used for in-orbit Cal/Val of HY-2B/C satellites in ten campaigns.The SSH and significant wave height of the altimeters showed good agreements with the GPS buoy solutions.

A method for predicting the water-flowing fractured zone height based on an improved key stratum theory

In the process of using the original key stratum theory to predict the height of a water-flowing fractured zone(WFZ),the influence of rock strata outside the calculation range on the rock strata within the calculation range as well as the fact that the shape of the overburden deformation area will change with the excavation length are ignored.In this paper,an improved key stratum theory(IKS theory)was proposed by fixing these two shortcomings.Then,a WFZ height prediction method based on IKS theory was established and applied.First,the range of overburden involved in the analysis was determined according to the tensile stress distribution range above the goaf.Second,the key stratum in the overburden involved in the analysis was identified through IKS theory.Finally,the tendency of the WFZ to develop upward was determined by judging whether or not the identified key stratum will break.The proposed method was applied and verified in a mining case study,and the reasons for the differences in the development patterns between the WFZs in coalfields in Northwest and East China were also fully explained by this method.

GmSTF accumulation mediated by DELLA protein GmRGAs contributes to coordinating light and gibberellin signaling to reduce plant height in soybean

Plant height influences plant architecture,lodging resistance,and yield performance.It is modulated by gibberellic acid(GA)metabolism and signaling.DELLA proteins,acting as central repressors of GA signaling,integrate various environmental and hormonal signals to regulate plant growth and development in Arabidopsis.We examined the role of two DELLA proteins,GmRGAa and GmRGAb,in soybean plant height control.Knockout of these proteins led to longer internodes and increased plant height,primarily by increasing cell elongation.GmRGAs functioned under different light conditions,including red,blue,and far-red light,to repress plant height.Interaction studies revealed that GmRGAs interacted with the blue light receptor GmCRY1b.Consistent with this,GmCRY1b partially regulated plant height via GmRGAs.Additionally,DELLA proteins were found to stabilize the protein GmSTF1/2,a key positive regulator of photomorphogenesis.This stabilization led to increased transcription of GmGA2ox-7b and subsequent reduction in plant height.This study enhances our understanding of DELLA-mediated plant height control,offering Gmrgaab mutants for soybean structure and yield optimization.

Characterization of the Main Effects, Epistatic Effects and Their Environmental Interactions of QTL on the Genetic Basis of Plant Height and Heading Date in Rice

Main-effect QTL, epistatic effects and their interactions with environment are important genetic components of quantitativetraits. In this study, we analyzed the QTL, epistatic effects and QTL by environment interactions (QE) underlying plantheight and heading date, using a doubled-haploid ( DH) population consisting of 190 lines from the cross between anindica parent Zhenshan 97 and a japonica parent Wuyujing 2, and tested in two-year replicated field trials. A geneticlinkage map with 179 SSR (simple sequence repeat) marker loci was constructed. A mixed linear model approach wasapplied to detect QTL, digenic interactions and QEs for the two traits. In total, 20 main-effect QTLs, 9 digenic interactionsinvolving 18 loci, and 5 QTL by environment interactions were found to be responsible for the two traits. No interactionswere detected between the digenic interaction and environment. The amounts of variations explained by QTLs of maineffect were 53.9% for plant height and 57.8% for heading date, larger than that explained by epistasis and QEs. However,the epistasis and QE interactions sometimes accounted for a significant part of phenotypic variation and should not bedisregarded.

Height connection across sea by using satellite altimetry data sets,ellipsoidal heights,astrogeodetic deflections of the vertical,and an Earth Gravity Model

Islands and the mainland are separated by seas,and the distances between them might be so long that the height on the mainland cannot be exactly translated to the islands,resulting in different height systems on the mainland and the islands.In this study,we used astrogeodetic deflections of the vertical and ellipsoidal heights of points on the mainland and island near their coastlines to implement height connection across sea areas.First,the modeled gravity and modeled astrogeodetic vertical deflections of segmentation points along connecting routes over the sea between the mainland and the island were determined by Earth Gravity Model(EGM),and the ellipsoidal heights of segmentation points were determined by the satellite altimetry data sets.Second,we used a linear interpolation model to increase the precision of the vertical deflections of segmentation points.Third,we computed the geopotential difference of points between the mainland and the island using a method derived from geopotential theory and the astronomical leveling principle.Finally,we estimated the normal height of the point on the island using the geopotential-difference iterative computation approach.Using observed data of normal heights,ellipsoidal heights,and astrogeodetic vertical deflections referring to height sites in Qingdao,Shandong Province,we conducted a numerical experiment involving the normal height connection across sea regions.We determined the data of the ellipsoidal heights and gravity of segmentation points along the connecting route across the water in the numerical experiment using DTU10.The distance of the height connection across the sea was approximately 10.5 km.According to China's official leveling specifications,the experimental results met the criterion of third-class leveling precision.

The HD-Zip transcription factor GhHB12 represses plant height by regulating the auxin signaling in cotton

Upland cotton(Gossypium hirsutum L.)is the most important natural textile fiber crop worldwide.Plant height(PH)is a significant component of plant architecture,strongly influencing crop cultivation patterns,overall yield,and economic coefficient.However,cotton genes regulating plant height have not been fully identified.Previously,an HD-Zip gene(GhHB12)was isolated and characterized in cotton,which regulates the abiotic and biotic stress responses and the growth and development processes.In this study,we showed that GhHB12 was induced by auxin.Moreover,overexpression of GhHB12 induces the expression of HY5,ATH1,and HAT4,represses the spatial-temporal distribution,polar transport,and signaling of auxin,alters the expression of genes involved in cell wall expansion,and restrains the plant height in cotton.These results suggest a role of GhHB12 in regulating cotton plant height,which could be achieved by affecting the auxin signaling and cell wall expansion.