Clinical Value of Transperineal 3D Volume Ultrasound Combined with 2D High Frequency Ultrasound in Anal Fistula

Objective: To explore the clinical diagnostic value of transperineal volume ultrasound combined with two-dimensional high-frequency ultrasound for anal fistula. Methods: A total of 52 patients with anal fistula admitted to the Affiliated Hospital of Shaanxi University of Traditional Chinese Medicine from December 2017 to July 2018 were selected. They were all undergoing transperineal 3D volume ultrasound combined with 2D high-frequency ultrasound examination, and the diagnosis results were analyzed. The results of ultrasonography and surgical pathology were compared. Results: Among 52 patients, 3D volume ultrasound combined with 2D high-frequency ultrasound were used to diagnose 32 cases of anal fistula intersphincteric type, 14 cases of transsphincter type, 5 cases of supra-sphincter type, and 1 case of extra-sphincter type. T supervisor classification accuracy rate is 90%. The detection rate of branch pipes was 92%, and the compliance rate of internal fistula was 95%. Two-dimensional high-frequency ultrasound was used to diagnose 34 cases of anal fistula intersphincteric type, 14 cases of transsphincter type, 4 cases of supra-sphincter type, and 0 cases of extra-sphincter type. The detection rate of branch canals was 42%, and the accuracy of type classification was 90%. The coincidence rate was 95%. There was a statistically significant difference in the detection rate of the anal fistula branch and the coincidence rate of the internal fistula between the two methods (both P Conclusion: 1) The overall coincidence rate of three-dimensional volumetric ultrasound combined with two-dimensional high-frequency ultrasound in the diagnosis of anal fistula is high;2) Three-dimensional volumetric ultrasound technology has great application prospects in infants and anal fistulas.

Combined load bearing capacity of rigid piles embedded in a crossanisotropic clay deposit using 3D finite element lower bound

In this study,an iterative-based three-dimensional finite element lower bound in association with the second-order cone programming method is adopted to evaluate the limit load of a single pile embedded in cross-anisotropic soils under general loading condition.The lower bound solutions of the pile embedded in an anisotropic soil deposit can be found by formulating the element equilibrium,equilibrium of shear and normal stresses along discontinuities,boundary conditions,yield function,and optimizing the objective function through the second-order cone programming method in conjunction with an iterative-based update procedure.A general loading condition is considered to profile the expansion of the safe load in the vertical-horizontal-moment(V-H-M)space.The results of this study are compared and validated against three different cases including an isotropic lateral loading,anisotropic end bearing capacity,and a pile embedded in an isotropic soil deposit under general loading condition.A parametric study is conducted to evaluate the impact of different influencing factors.It was found that the effect of anisotropy on the variation of lateral limit load of a single pile is more pronounced than the corresponding vertical and bending moment limit loads,whereas the interface properties have more significant effects on the vertical and bending moment limit loads in comparison to the lateral limit load.

Determination of Luzhou-flavor liquor ages by three-dimensional fluorescence spectroscopy combined with NMF

The determination of Luzhou-flavor liquor ages is carried out by three-dimensional fluorescence spectroscopy combined with non-negative matrix factorization(NMF). 37 samples of aged liquors with weighted ages of 15, 20 and 25 years were prepared by blending three Luzhou-flavor original base liquors with storage ages of 10, 20 and 30 years in different proportions. The fluorescence spectra of the samples were measured, and then factorized into basis matrix and coefficients matrix by multiplicative iterative NMF. The fluorescence spectra, reconstructed from the basis matrix, are similar to the original spectra. The coefficients matrix is taken as the input of support vector machine(SVM) to establish a prediction model for the determination of liquor ages. Compared with the principal component analysis, the prediction model based on SVM has a predicted accuracy better than 91.7%. This method can provide helps for the market supervision on the aged liquors.

Numerical Simulation of Interaction Between Laminar Flow and Elastic Sheet

A numerical simulation of the interaction between laminar flow with low Reynolds number and a highly flexible elastic sheet is presented. The mathematical model for the simulation includes a three-dimensional finitevolume based fluid solver for incompressible viscous flow and a combined finite-discrete element method for the three-dimensional deformation of solid. An immersed boundary method is used to couple the simulation of fluid and solid. It is implemented through a set of immersed boundary points scattered on the solid surface. These points provide a deformable solid wall boundary for the fluid by adding body force to Navier-Stokes equations. The force from the fluid is also obtained for each point and then applied on the boundary nodes of the solid. The vortex-induced vibration of the highly flexible elastic sheet is simulated with the established mathematical model. The simulated results for both swing pattern and oscillation frequency of the elastic sheet in low Reynolds number flow agree well with experimental data.

Assimilation of Radar and Cloud-to-Ground Lightning Data Using WRF-3DVar Combined with the Physical Initialization Method——A Case Study of a Mesoscale Convective System

Radar data, which have incomparably high temporal and spatial resolution, and lightning data, which are great indicators of severe convection, have been used to improve the initial field and increase the accuracies of nowcasting and short-term forecasting. Physical initialization combined with the three-dimensional variational data assimilation method(PI3 DVarrh) is used in this study to assimilate two kinds of observation data simultaneously, in which radar data are dominant and lightning data are introduced as constraint conditions. In this way, the advantages of dual observations are adopted. To verify the effect of assimilating radar and lightning data using the PI3 DVarrh method, a severe convective activity that occurred on 5 June 2009 is utilized, and five assimilation experiments are designed based on the Weather Research and Forecasting(WRF) model. The assimilation of radar and lightning data results in moister conditions below cloud top, where severe convection occurs;thus, wet forecasts are generated in this study.The results show that the control experiment has poor prediction accuracy. Radar data assimilation using the PI3 DVarrh method improves the location prediction of reflectivity and precipitation, especially in the last 3-h prediction, although the reflectivity and precipitation are notably overestimated. The introduction of lightning data effectively thins the radar data, reduces the overestimates in radar data assimilation, and results in better spatial pattern and intensity predictions. The predicted graupel mixing ratio is closer to the distribution of the observed lightning,which can provide more accurate lightning warning information.

Requirement of ultra-high voltage GIS arrester to voltage gradient of metal-oxide varistor

The surge arrester with excellent protection characteristics would decrease the overvoltage level ap- plied on the power apparatus to reduce their insulation levels and manufacturing bottleneck. The arrester for the 1000-kV ultra-high voltage ac power transmission system is designed as tank-type structure. The field-circuit combination numerical method combining the three-dimensional finite element method with circuit is proposed to analyze the potential distribution of GIS arrester. By comparing several design schemes, the most effective method to improve the potential distribution along the varistor column is to increase the voltage gradient of the ZnO varistor. Synthesizing several influential factors, the suitable voltage gradient of ZnO varistor should be controlled to 435 V/mm, and the resulted nonuniform degree of the potential distribution along the varistor column inside the GIS arrester would be controlled smaller than 10%. The result in this paper provides the fundamental technical index for the study of the high voltage gradient ZnO varistors.