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The Jingyang–Weinan Fault that Xi’an Metro Line 10 crosses is a Holocene active fault, and its future stick-slip earthquakes and coseismic dislocations pose a potential threat to the metro line. To reveal the deformation and stratum stress characteristics of the site caused by the stick-slip seismic and coseismic dislocations of the Jingyang–Weinan Fault zone, based on the Jingyang–Weinan fault zone crossed by Xi’an Metro Line 10, the geomechanical model of the fault zone site coseismic dislocations and stick-slip seismic was established, and the numerical simulation analysis of the stratum deformation and stress field characteristics of fault zone site was carried out considering different dislocation amounts and seismic intensity. The results show that under the coseismic dislocation, the stress reduction and strengthening zones appear in the hanging wall and footwall near the fault zone, and the site presents an inverse “S” shaped differential settlement failure. The differential displacement peaks at the fault zone, and the plastic zone is concentrated here. The deformation range and plastic zone of the hanging wall are 1.67 times and 2.50 times more than that of the footwall, respectively. The displacement and differential deformation of the site near the fault zone reach the peak value under the stick-slip earthquake. The influence range of the site displacement during the large earthquake is approximately 6.50 times more than that during the medium earthquake. It has a typical magnification effect on the hanging wall, and the displacement decreases linearly far away from the fault zone. The amplification factor of peak surface acceleration (PGA) in the large earthquake is 1.14 times more than that in the medium earthquake. The site shows “V” shear failure; the plastic zones of hanging wall and footwall in the large earthquake is about 1.40 times and 1.00 times larger than that in the medium earthquake, respectively. This study can provide a scientific basis for the seismic fortification of Xi’an Metro Line lines crossing the Jingyang–Weinan fault zone.

Background Postprandial glucose excursions is the main cause of elevated glycated hemoglobin levels in patients with diabetes mellitus. Controlling postprandial glucose is also an important strategy for preventing and treating chronic complications of diabetes. Objective To evaluate the effect of protein preload meal pattern on postprandial glucose excursions in patients with type 1 diabetes mellitus (T1DM) . Methods This study is a randomized, open-label, within-subject crossover clinical registration study. We selected thirty-one T1DM patients aged 18-45 years with a course of disease >1 year who were admitted to the First People's Hospital of Yunnan Province from February 2019 to December 2021. After ten hours fasting, all patients ate two isocaloric test meals with the same ingredients, one is protein preload meals and another is mixed meals, on the 4th and 7th days of wearing continuous glucose monitoring systems (CGM), respectively. CGM was used to analyze the CGMS data 5 hours after a meal, including peak postprandial glucose, time to peak postprandial glucose, average blood glucose level; area under curve (AUC) for blood glucose, incremental area under curve (iAUC) for blood glucose, mean amplitude of glycemic excursions (MAGE), the incremental glucose peak (?Peak) and low (?Low), and the proportion of time of hypoglycemia and hyperglycemia events. We also used a generalized linear mixed model to compare the difference in blood glucose excursions during five hours post-prandial. Results Twenty-six T1DM patients were included in the statistical analysis. There was no significant difference in fasting blood glucose, peak blood glucose, mean blood glucose from 0 to 300 min, mean blood glucose from 180 to 300 min, the proportion of time when blood glucose>10 mmol/L (%), the proportion of time when blood glucose>13.9 mmol/L (%), MAGE, and ?Peak between protein preload meals and mixed meals (P>0.05). The peak time and ?Low of the protein preload meals were higher than those of the mixed meals, and the mean blood glucose (0-180 min) of the protein preload meals was lower than that of the mixed meals (P

In order to study the corrosion status and reasons of the sulfur - resistant tubings in Tahe oilfield and provide reasonable suggestions for tubing corrosion protection, the causes of corrosion failure of P110S tubing in a well were comprehensively analyzed by means of macro - morphological observation, physical and chemical property testing, metallographic structure analysis, scanning electron microscope observation and energy spectrum analysis based on field conditions. Results showed that the tubing’s chemical composition, mechanical properties and metallographic structure met API SPEC 5CT-2011 requirements, and a corrosion environment with high contents of CO2, Cl - and H2O was the main reason for the local corrosion of the inner wall of the tubing, which subsequently led to a serious thinning and fracture of the inner wall of the tubing. With the increase of the well depth, the service temperature of the tubing increased, and the corrosion degree of the tubing increased as well.

Path tracking control of articulated vehicles is a focus in the field of mine automation. Mathematical models and path tracking control methods are two key focal points of research in this area. For mathematical models of articulated vehicles, the classic kinematics model without side-slip is suitable as a reference model for low-speed autonomous driving control. However, when this model is used as the reference model, it may lead to an intensification of sliding. In any event, the four-degree-of-freedom dynamic model of articulated vehicles based on the Newton–Euler method meets the requirements of autonomous driving control in principle. However, this model cannot reflect both transient and steady steering characteristics. In the research of path tracking control methods, feedback linearization control, optimal control, sliding mode control, and other control methods without feedforward information cannot effectively solve the problem of a large error when vehicle tracking a reference path with large abrupt changes in curvature. Feedforward–feedback control can be used to solve the above problem, but when the reference path has diverse amplitudes of abrupt changes in curvature, it is necessary to automatically adjust the preview distance. Model predictive control, especially nonlinear model predictive control, can use feedforward information more effectively and does not need to consider the setting of the preview distance. This way, when the articulated vehicle tracks a reference path with large abrupt changes in curvature, accuracy can be effectively improved. Additionally, for the path tracking control of articulated vehicles based on nonlinear model predictive control, three aspects of research need to be deepened. First, for this control method, there is still a trend that the maximum value of the error increases as the reference velocity increases. Second, currently, this control method uses the kinematics model as the prediction model, so it cannot solve the twin problems of reduced accuracy and worsened safety, caused by the lateral velocity when the articulated vehicle runs at a higher reference velocity. Finally, real-time optimization research on this control method is needed.

The health condition of hot-rolling back-up rolls plays a key role in controlling the strip profile quality and rolling stability. The characteristics of nonlinearity, strong coupling, and the use of limited samples complicate the prediction of the back-up roll health state. The current back-up roll replacement strategy of each steel mill is generally determined according to a certain rolling time or rolling kilometer, and such a maintenance mode is based on experience. In actual experience, due to different strip specifications in each rolling cycle, the degrees of wear on the back-up rolls are different. Regular maintenance methods may easily lead to excessive wear of the back-up rolls and reduce the quality of the strip shape at the end of the unit, or premature roll replacement wastes the back-up roll performance. This paper proposed a construction method for the back-up roll virtual health index and a Copula function–based model for predicting the health condition of complex working conditions. The health condition of a pair of back-up rolls was characterized by combining roll bending and shifting data, and the back-up roll condition was divided by the K-means clustering method. The Copula prediction model was constructed using the process data under each working condition, and finally, according to the actual rolling schedule, the arrangement order combines the prediction results of the working conditions. The production performance data of a 1780-mm hot rolling line were used to verify the results. The results show that the proposed Copula-based prediction model can accurately and effectively predict the health condition of the back-up roll according to the rolling schedule; thus, it can serve as the basis of a more scientific strategy to guide the replacement and maintenance of the back-up roll.

In order to improve the timeliness and reliability of color image scaling algorithms,a high effective real-time color image scaling algorithm was proposed,which first generated the kernel look up table that could be used for whole target image based on Lanczos kernel,and interpolation of all target image pixels had only fixed point operation which had low computational complexity.Meanwhile,an optimized method for rasterizing pixels of target image was proposed,which needed little memory space but embraced high efficiency of memory utilization.The experiment results show that the proposed algorithm achieves good image quality,and the computational complexity is far more less than classic image scaling algorithms.So the proposed algorithm can effectively implement real-time resizing of color images and color videos in any scaling factors.

This is an essay in the field of mineral processing engineering. Aiming at the problem of difficult recovery of ultrafine ilmenite from a concentrator in Panzhihua-Xichang Area, a comparative study of flotation process was carried out. Using direct flotation, desliming flotation, "centrifugal-flotation", "superconducting flotation", "strong magnetic flotation", "suspension vibration-flotation" and other beneficiation processes, the test results show that: direct flotation and desliming flotation processes can not obtain titanium concentrate products with TiO2 grade greater than 46%. Suspension vibration and high intensity magnetic separation can obtain higher grade preenriched concentrate, which is conducive to the subsequent flotation operation. Centrifugation and superconductivity can obtain higher recovery of preenriched concentrate, which can ensure the effective recovery of ilmenite. But considering that superconducting preenrichment technology industry implementation investment is large, there is no mature industrial case at present; The high intensity magnetic separation and suspended vibration preconcentration process are easy to be industrialized, but the single processing capacity of the suspended vibration separator is limited. Therefore, the optimal flotation process was finally determined to be "strong magnetic flotation", which could obtain the index of titanium concentrate grade of 46.62%, recovery rate of 58.32% in open flotation operation and recovery rate of 43.78% in the whole process.

This is an essay in the field of mineral processing engineering. A low-grade fluorite ore is mainly composed of fluorite (28.85%), calcite (43.26%), quartz (12.01%) and feldspar (10.28%). Through detailed beneficiation test research，using acidized water glass and modified carbohydrate EM-318 as calcite inhibitors and using plant-based fatty acid soap EM-OL3 as fluorite collector,the fluorite concentrate with a grade of 97.59% and recovery of 90.98 % was obtained by the flowsheet of "-0.074 mm accounting for 65%, two roughings, one scavenging, and eight cleanings ". This experimental study shows that the combination of modified carbohydrate EM-318 and plant based fatty acid soap EM-OL3 as fluorite collector can efficiently separate fluorite from calcite,

To study the influence of grain arrangement on the surface profile of the workpiece, a mathematical model and its corresponding analytical algorithm of pyramidal abrasive belt grinding were established. The roughness value was simulated and predicted with Abaqus software. Grinding tests were carried out on the robot grinding system platform with pyramidal abrasive belt, and the surface profile were inspected and then compared with the simulation. The results show that the simulated roughness and the measured values have similar variation trend with good consistency, where the error is within 0.03 μm and the maximum error rate is 16.6%. The theoretical simulation and test results remain consistent, indicating that the model could be used to predict the surface roughness of workpiece ground with pyramidal abrasive belt.

Surface wave tomography is a widely used geophysical method to measuring seismic velocity and anisotropy in the crust and upper mantle. This paper briefly reviewed the history of surface wave tomography, and summarized the principles and advantages of multiple surface wave tomography methods (i.e., two-station method, two-plane-wave method, Eikonal and Helmholtz surface wave tomography, ambient noise tomography, and direct surface wave tomography). The theory and application of the two-station method are straightforward, but this method requires the earthquake and seismic stations to be located in the same great circle. This restriction results in a low lateral resolution phase velocity map for regions where stations are sparse and deployment times short. The two-plane-wave method can overcome the effect of scattering and multipathing of seismic wave propagation on phase velocity dispersions, but this method requires high-quality surface wave waveforms and is usually suitable for regional seismic networks. The Eikonal and Helmholtz surface wave tomography can directly compute the phase velocities and azimuthal anisotropy straightforwardly without any processes of forward modeling and inversion, but this method is limitedly suitable for high-density and orderly seismic arrays. In comparison to the Eikonal surface wave tomography method, the Helmholtz surface wave tomography approach analyzes both the phase and amplitude of the waveform and can produce better results. Ambient noise tomography can obtain high-resolution crustal structure without seismic events. However, this method is difficult to obtain long-period phase velocities, resulting in a lack of constraints on the mantle and lithosphere structure. Direct surface wave tomography can obtain the shear-wave velocity and azimuthal anisotropy from dispersive curves without the inversion process of phase velocity maps. We conducted detailed comparisons of the phase velocity maps at the short-intermediate periods (20～40 s) previously obtained from these surface wave tomography methods in the central-northern, northeastern and southern Tibetan Plateau. The comparisons demonstrated that the Rayleigh and Love wave phase velocity maps from different tomography methods show highly consistency in velocity variation patterns at same periods. The results show that the plateau's interior by characterized with low-velocities in phase velocity maps at intermediate and long periods, whereas relatively high velocities dominate adjacent regions, such as the Qaidam Basin and Sichuan Basin. These features indicate that the Tibetan Plateau's mid-lower crust and upper mantle tend to be weaker and easily deform during the northward movement of the Indian plateau and the barrier of the strong blocks (e.g., the Qaidam Basin and the Alashan Platform). The short periods phase velocity maps (i.e., 20～40 s) reveal that the mid-lower crustal flow of the Tibetan Plateau escapes southward surrounding the weakening zones (i.e., the Red River Fault and the Xianshui River Fault) due to the barrier of the strong Chuandian tectonic block. The Qilian Orogen also shows low velocities in the phase velocity maps at the short-intermediate periods, which is likely due to thermal anomaly with localized mantle upwelling. It is noteworthy that the Rayleigh-wave and Love-wave phase velocities at different period ranges (e.g., 4～200 s) can be obtained via incorporating earthquake surface wave tomography and ambient noise tomography. Those phase velocities can be used as input to inverting three-dimensional shear wave velocities and radial anisotropy models simultaneously. This paper envisions that integrating higher-mode earthquake surface wave tomography, adjoint tomography, and joint inversion could obtain higher resolution and more reliable crustal and upper mantle structures.

Epilepsy is a brain dysfunction syndrome caused by abnormal synchronous discharge of neurons. Until now, the pathogenesis has not yet been fully elucidated. In recent years, a growing number of experimental and clinical studies have shown that epilepsy is a pathological process under the action of multiple factors. The academic situations including two-way reasoning, multiple arguments and crosswise multidisciplinary demonstration are emerging. doi: 10.3969/j.issn.1672-6731.2014.11.004