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The health status of the planetary gears in the cutting section of shearer's rocker arm directly affects the cutting efficiency. The strong noise interference caused by multiple impacts during the cutting of coal and rock by the shearer, the complex gear structure, and the variable transmission path make it difficult to extract fault features. In order to solve the above problems, a fault diagnosis method for planetary gears in shearer based on spectral average denoising and correlation spectrum is proposed. Based on the distribution features of signal spectrum and the random features of noise, the spectrum average denoising method is adopted to suppress the interference of noise on the signal spectrum and obtain the signal denoising spectrum. The method constructs relevant spectra to establish the intrinsic relationship between few sample denoising spectra and multi sample denoising spectra, and reduce the demand for sample size for average spectrum denoising. The method uses a one-dimensional convolutional neural network (1D CNN) to establish an accurate mapping relationship between correlation spectra and fault categories, with correlation spectra as input and fault categories as output, to achieve planetary gear fault classification and recognition. The experimental verification of the fault diagnosis method for planetary gears in shearer based on spectral average denoising and correlation spectrum is carried out on the drivetrain diagnostics simulator transmission system fault diagnosis experimental platform. The results show that the method can enhance the key frequency that characterizes the fault features. The overall recognition rate for five types of health status signals of planetary gears, including normal, broken teeth, wear, missing teeth, and cracks, reaches 96%. Gear fault diagnosis can be effectively and accurately achieved when the signal-to-noise ratio is not less than 15 dB.

Coal and gangue sorting methods based on heavy-medium coal selection technology, jigging technology, flotation technology, dry coal selection technology and γ-ray detection method have high investment costs, low sorting efficiency and serious environmental pollution. The accuracy of the coal gangue sorting method based on CCD cameras is not high, and the X-ray based coal gangue sorting technology can harm the health of personnel. Infrared thermal imaging technology has the advantage of being unaffected by light and dust, and will not cause harm to the human body. A coal gangue recognition method based on infrared thermal imaging has been proposed. Firstly, coal and gangue pass through the heating area under the conveyor belt, and the temperature of the center point of coal and gangue is monitred through an infrared thermal imager to obtain the temperature of the heated coal and gangue. The infrared thermal imager is used to capture the uniformly heated coal and gangue in the heating area, obtaining infrared grayscale and color images of the coal and gangue. Secondly, Gaussian filtering is used to preprocess and extract features from the infrared grayscale images and infrared color images of coal and gangue. The grayscale mean of the infrared grayscale image, the grayscale value feature corresponding to the maximum frequency, and the G-channel first-order moment and G-channel second-order moment features of the infrared color image are used as sorting features. The above four features are used as inputs for the classification model. Finally, support vector machine (SVM) is used for classification and recognition to achieve the goal of recognizing coal and gangue. The experimental results show that the coal gangue recognition method based on infrared thermal imaging has achieved an accuracy rate of over 98% for the sorting of bituminous coal, anthracite, and lignite, and has a good classification effect.

Photoelectrocatalytic technology is one of the most promising methods to solve the problems of environmental pollution and energy shortage.Based on the photoelectrochemical properties of semiconductor minerals or the natural physical characteristics of non-semiconductor minerals, the photoelectrocatalytic mineral materials were constructed by compositing mineral with photoelectrocatalytic functional body, with the characteristics of low cost, good environmental compatibility and excellent property, which have received wide attention in the new field of mineral utilization. On the basis of limiting whether the research of photoelectrocatalytic mineral materials belong to the scope of mineral application, the mineral components and characteristics of the photoelectrocatalytic mineral materials were introduced, their classification, preparation methods, as well as the enhanced mechanism of catalytic activity by minerals were discussed. Finally, the research status of photoelectrocatalytic mineral materials used in the treatment of wastewater, hydrogen evolution by photoelectrocatalysis water splitting, CO2 energy utilization were summarized. It is pointed out that attention should be paid to the intrinsic photoelectric properties of minerals, the establishment of the relationship between material composite structures and efficiency, and the clarification of the mechanism by which material mineralogical properties affect photocatalysis. The application research of photocatalysis mineral materials in new energy, chemical synthesis, and mineral/microbial interactions should be expanded.

In a vehicular status update network based on broadcast communication, a D/Geo/1/1 queuing mechanism with minimum timestamp priority was adopted to transmit data packets.The queuing theory was used to analyze the age-ofinformation (AoI) outage probability of the receivers and the average transmit power of the transmitter.Based on the monotonicity of the AoI outage probability with respect to packet sampling rate and transmit power, an iterative algorithm for jointly optimizing sampling rate and transmit power was proposed to minimize the maximum AoI outage probability of all receivers under power constraint, which fairly improved information freshness of all receivers under sampling and power control.Simulation results verify the accuracy of theoretical analysis and the efficiency of the algorithm.

In this study, Ca2+-induced sodium alginate hydrogel was used as a model. The rheological properties were measured via steady-state shear, oscillation strain sweep, and yield stress. The network of sodium alginate hydrogels was analyzed using water distribution and rheological parameters. After a comprehensive analysis of the morphology and Micro-CT structure of 3D printing products, the mathematical relationship between rheological parameters and 3D printing effect was established using the Spearman's correlation analysis. The results showed that the highest score of 3D printing product was prepared at the mass ratio of SA to Ca2+ at 24:1 and the concentration of SA at 4.5%. At the same time, the filament structure of 3D printing product was fine and the porosity was 12.21%. Rheological parameters of K, η1, G', G", τ0 and τy were 255.1 Pa·sn, 2740 Pa·s, 3509 Pa, 673.2 Pa, 261.4 Pa, and 51.62 Pa, respectively. The capillary water (about 99.20%) was dominant in the gel network, showing strong water holding capacity of hydrogel. Results of correlation analysis showed that the viscosity properties (K, η1, and G") were negatively correlated with the extrudability, and the correlation coefficient was -0.577. The self-supporting capacity of the 3D printing product was positively correlated with the elastic modulus and stress (G', τ0, and τy) (P

Given the low accuracy of the traditional electricity theft detection method based on one-dimensional electricity consumption data mining and analysis， a detection method for electricity theft by distribution network users based on a hybrid neural network is proposed. Firstly， to enhance the characteristic difference between the electricity consumption of normal users and that of power theft users， the Markov transition field （MTF） is used to transform one-dimensional electricity consumption data into two-dimensional graphs. Moreover， to improve the accuracy and generalization of the model， profile data of users' electricity consumption is introduced. Then， the hybrid neural network is used to extract and fuse the feature quantities of the preprocessed two-dimensional electricity consumption graphs and profile data respectively to detect electricity theft by distribution network users. Finally， the effectiveness and accuracy of the proposed method are verified through two sets of comparison experiments. The experimental results show that the method based on a hybrid neural network is superior to other models in detection accuracy of electricity theft， recall rate， and AUROC （area under the receiver operating characteristics）， and has higher detection performance.

The addition of trace Mo and Nb elements to the Fe-Cr-Al ferrite alloy of the accident tolerant fuel (ATF) cladding can play a role in solid solution strengthening and precipitation. The precipitated Laves phase distributes at the grain boundary and subgrain boundary, which can fix the grain boundary and hinder grain growth, improving the thermal stability of the alloy. According to another view, the pinning effect of the Laves phase is smaller than the solute drag effect (SDE) and does not contribute significantly. The phase field method was used to quantitatively simulate the hindrance of Mo and Nb solute elements to grain boundary migration in order to study SDE on grain boundary migration during grain growth. To model the effect of the solute elements on grain boundary migration, a polycrystalline phase field model and a solute drag additional term were introduced to the existing phase field model, and the specific expressions of these models were derived for simulation. The simulation results show that the phase field method can observe the unsteady solute separation process, in comparison to the classical steady-state SDE model. In addition, the distribution of solute at grain boundaries with different migration rates and the corresponding SDE dissipation energy at those rates are also obtained, and the action range of Nb and Mo element SDE is determined. The degree of solute segregation at the grain boundary is negatively related to the grain boundary migration rate. When the grain boundary migration rate is greater than 1×10-5 m/s, the segregation of Mo and Nb at the grain boundary tends to zero. The relationship between SDE dissipation energy and interface migration rate is parabolic, with a peak value of 69.7 J/mol at a rate of 1.124×10-6 m/s. When the interface migration rate is less than 1.124×10-6 m/s, the concentration distribution deviates from the equilibrium state and the dominant SDE dissipation energy increases. When the interface migration rate is greater than 1.124×10-6 m/s, the solute separates and the degree of segregation decreases, while the dominant SDE dissipation energy decreases. During the early stage of grain growth, the solute at the grain boundary is not in a saturated state and the interface migration rate is too high, resulting in no obvious SDE. At the same time, the high interface migration rate causes solute retention. The results of the study show that the model is suitable for simulating the SDE in the polycrystalline growth process, and can provide valuable information for a deeper understanding of the solute dragging process of Mo and Nb in materials and for material design and performance prediction.

Regarding the poor visible light response and the difficulty in synchronously driving photocatalytic reduction and oxidation reactions of MOFs, In2S3/UiO-67 composites (IM-1, IM-3, and IM-5) were prepared by deposition of in situ generated In2S3 species on the surface of UiO-67(Zr-MOF), and the formation of heterostructure was confirmed by PXRD, FT-IR and XPS characterization. Under the irradiation of 500 W xenon lamp, the reduction efficiency of IM-3 for Cr(Ⅵ) reached 92.4% within 60 min, providing the reduction rate of 2.3 and 20 times that of pure In2S3 and Zr-MOF, respectively. The degradation efficiency for RhB was 78% within 180 min, with the degradation rate of 1.75 and 2.3 times of that of pure In2S3 and Zr-MOF. Moreover, the migration direction of photogenerated carriers were elucidated by XPS, and the photocatalytic reaction mechanism was further revealed in combination with free radical trapping experiments.

【Objective】 Polypropylene microplastics are fragments of polypropylene. They exist in soil and have potential impact on soil environment. This paper investigates their influence on water flow and salt redistribution in soil under drip irrigation. 【Method】 The experiment was conducted in cuboid tanks packed by saline soil. Steady water infiltration into the soil was maintained by a Martensian flask; the infiltration rate was controlled at 0.36 L/h by a rotameter. The content of polypropylene microplastics in the soil was 2%, and the salt content was 0.5%, 4% or 7%. 【Result】 Soil water content and initial soil salt content were positively correlated. The average water content in the soil with initial salt content of 7.0% was 9.4% and 11.2% higher than that in soils with initial salt contents of 4.0% and 0.5%, respectively (P

Marine carbon geological sequestration is crucial for achieving carbon peaking and carbon neutralization in China. However, there exist risks of carbon dioxide (CO2) leakage that leads to seabed geological disasters, severely threatening the safety of marine engineering. Therefore, it is of great practical significance to monitor the environmental geology of sequestration areas. This study briefly introduces several demonstration cases of marine carbon geological sequestration and explores the disaster mechanism associated with CO2 leakage in seabed sequestration areas. It also sorts out the marine environment monitoring technologies in typical CO2 controlled release tests via examples and analyzes the environmental geology monitoring technologies related to CO2 leakage, including seismic investigation and monitoring, resistivity monitoring, gravity monitoring, seabed deformation monitoring, and sediment pore pressure monitoring. Moreover, the prospects of China’s marine carbon geological sequestration and its environmental geology monitoring are presented. We suggest that long-time, low-cost, and real-time monitoring technologies should be developed, a systematic and intelligent multi-dimensional disaster identification model should be established in combination with the baseline investigation of the sequestration areas, and a multi-faceted, multi-level, and multi-disaster monitoring and forecasting system should be built.

Due to the complex working conditions of high noise, low illumination, and blurred movement in coal mines underground, as well as the phenomenon of coal gangue easily gathering, it is difficult to extract features from coal gangue object detection models. The classification and positioning of coal gangue are inaccurate. In order to solve the above problems, a coal gangue recognition method based on the CED-YOLOv5s model is proposed. Firstly, the coordinate attention (CA) mechanism is introduced into the YOLOv5s backbone network, which encodes feature maps by embedding coordinate information into channel relationships and long-range dependencies. The method fully utilizes channel attention information and spatial attention information to make the model focus more on important features and suppress irrelevant information. Secondly, the EIoU regression loss function is introduced in the detection head of YOLOv5s to minimize the width and height difference between the object box and anchor box. It enhances the position and boundary information of the object, improves the positioning precision and convergence speed of the model in dense objects. Finally, a lightweight decoupling head is introduced in the detection head of YOLOv5s, decoupling separate feature channels for classification and regression tasks. It solves the interference problem between the coupling head part of the class task and the regression task in the original model, further improving the parallel operation efficiency and detection precision of the model. The experimental results show that the CED-YOLOv5s model has the best overall performance compared to other YOLO series object detection models. It has an average detection precision of 94.8%, an improvement of 3.1% compared to the YOLOv5s model, and a detection speed of 84.8 frames/s. The results can fully meet the real-time detection requirements of coal gangue in coal mines.

The coal gangue recognition method based on visible light images has low accuracy and slow recognition speed. The coal gangue recognition method based on high-energy ray transmission has significant radiation, resulting in limited application. The infrared thermal imaging has advantages such as strong penetration and no influence from light. But the surface temperature of coal and gangue is relatively close at room temperature, resulting in no significant difference between coal and gangue in infrared thermal images, making it difficult to achieve good recognition results. In order to solve the above problems, a coal gangue recognition method based on water heat transfer and infrared thermal imaging is proposed. The method conducts infrared thermal imaging experiments on coal and gangue under different water temperatures (18, 21, 24, 27, 30 ℃). The method distinguishes between coal and gangue based on the differences in infrared thermal images and temperature changes. The experimental results show that the infrared thermal images of coal and gangue are different at different water temperatures. When the water temperature is lower than the ambient temperature, there is a significant difference between the infrared thermal images of coal and gangue. Under the same water temperature conditions, the difference between the infrared thermal images of coal and gangue gradually increases with time. The surface temperature changes of coal and gangue both show an increasing trend with the increase of water temperature and time. But the surface temperature changes of gangue are greater than those of coal. When the water temperature is 18℃ and the time is 180 s, the difference and temperature difference between the infrared thermal images of coal and gangue reach their maximum. This indicates that low-temperature water can serve as a heat transfer medium, which is more conducive to creating a large temperature difference between coal and gangue. The accurate and rapid recognition of coal and gangue infrared thermal images can be achieved.

Objective To investigate the effect of intraoperative epileptic seizure on postoperative mood and muscle strength during awake anesthesia (AA) for the resection of gliomas. Methods A total of 90 patients with glioma admitted to Xijing Hospital, Air Force Military Medical University of Chinese PLA from September 2020 to September 2022 were collected and divided into general anesthesia group (GA group, n = 30), awake anesthesia without intraoperative epileptic seizure group (AA group, n = 30), and awake anesthesia with intraoperative epileptic seizure group (AA + IE group, n = 30) according to the anesthesia method and the presence of intraoperative epileptic seizure. Patients' mood and muscle strength changes were assessed preoperatively and one week postoperatively by using Hamilton Anxiety Rating Scale (HAMA), Hamilton Depression Rating Scale (HAMD) and muscle strength division method. Results The differences in HAMD score (F = 9.985, P = 0.000) and muscle strength (F = 4.472, P = 0.014) at one week postoperatively were statistically significant among 3 groups. HAMD score was increased in AA group (q = 3.177, P = 0.014) and AA + IE group (q = 9.468, P = 0.000) when compared with GA group. HAMD scores was increased in AA + IE group (q = 6.290, P = 0.003) when compared with AA group. Postoperative muscle strength of AA group (q = 9.172, P = 0.006) and AA + IE group (q = 5.310, P = 0.000) was increased when compared with GA group. Muscle strength of AA + IE group was decreased compared with AA group (q = 3.862, P = 0.007). Conclusions Awake anesthesia can aggravate postoperative depression, but improve muscle strength. Intraoperative epileptic seizure can aggravate postoperative depression and decrease muscle strength. A reasonable preventive treatment plan needs to be developed in advance to reduce the incidence of intraoperative epileptic seizure.

Objective: This study aimed to investigate the effects of 6 kinds of probiotics and their different adding ways on the production of rice wine. Methods: The probiotic rice wine was prepared by adding Lactobacillus rhamnosus BV-77, Lactobacillus fermentans TF-331, Lactobacillus saliva AP-32, Lactobacillus johnsoni MH-68, Lactobacillus acidophilus TYCA-06 and Lactobacillus casei CS-773. To compare the effects of saccharifying enzyme alone, saccharifying enzyme and yeast at the same time and adding methods （probiotic bran koji and probiotic powder） on alcohol content, reducing sugar, total acid and sensory quality of rice wine. Results: Yeast can promote the fermentation of probiotic rice wine and significantly improve the alcohol content and reducing sugar content of rice wine. The rice wine was fermented at 30 ℃ for 3 days by adding 200 U/g saccharifying enzyme and 0.04% yeast, with the highest alcohol content and reducing sugar content of 7.20%vol and 270.00 mg/mL, respectively, and the lowest total acid content of 8.40 mL/L. The rice wine is relatively rich in taste. Conclusion: Lactobacillus fermentans is the most suitable probiotics for rice wine brewing among 6 kinds of probiotics.

A variety of microorganisms inhabit the human skin, including bacteria, fungi, and viruses. Skin microbiota plays an important role in maintaining host skin homeostasis and the skin barrier function. Volatiles produced by skin microorganisms in different individuals have varying effects on the regulation of host-seeking behavior in the mosquito. In this review, we summarize the diversity of skin microorganisms, the volatiles produced by skin microorganisms and the regulatory effects of skin microorganisms on mosquito-borne infectious diseases, which could provide clues for developing new strategies for the prevention and intervention of mosquitoborne infectious diseases.

In the goaf of the high gas and spontaneous combustion coal seam, the gas drainage is mutually contradictory and restrictive to the prevention and control of coal spontaneous combustion. For this, we analyzed the disaster mechanism of gas and coal fire coupling disaster, determined the main factors affecting the coupling disaster, and identified the potential ethical risks of the existing gas and coal spontaneous combustion prevention technology. Based on analytic hierarchy process, the ethical risk assessment model of gas and coal fire coupling disaster was established and applied in 7436 working face of Kongzhuang Coal Mine. The results show that the weight of the coal spontaneous combustion during the mining of 7436 working face is 0.262 3, the weight of the gas disaster is 0.205 4, and the weight of the gas and coal fire coupling disaster is 0.529. Special attention should be paid to the occurrence of the gas and coal fire coupling disaster during mining. The probability of coal spontaneous combustion disaster is higher than that of gas disaster when coal spontaneous combustion disaster and gas disaster are treated respectively.

The paper mainly expounds the principles， differences and selection principles of ordinary least squares and weighted least squares in univariate linear regression， and introduces the application in four aspects， including heteroscedasticity test， optimal weight function selection， regression equation test and comparison of fitting quality. The application and existing problems of the weighted least squares method at home and abroad is analyzed. Suggestions on how to promote the application research of regression technology in analytical chemistry to provide reference and inspiration for researchers are put forward.

Fused Deposition Modeling（FDM） has the advantages of fast forming speed and simple operation. Printing speed, printing layer thickness and printing temperature affect the equivalent stress of the workpieces, and then affect its mechanical properties. It is different from direct setting printing temperature as the initial temperature in the birth and death unit simulation. Through experiment and fluid simulation, the temperature of the single fuse when it contacts the plate is got, as the initial temperature of the multilayer superposition simulation. We calculate and fit out the function of heat transfer coefficient, considering printing parameters. With the FDM Multi Layer Stacking simulation, the stress of the workpieces under different parameters is got. Then correlated and compared with the tensile strength obtained by the tensile test under the same parameters. From the point of the stress, we analyzed the influence of the printing parameters on the tensile strength. The supplementary experiment is designed, and find the tensile strength of ploylactic acid（PLA） workpieces reach the maximum when the printing layer thickness is as far as small, the printing speed and the printing temperature are appropriate.

With the increase of the power load in power grid， the short circuit level continues to rise， and excessive short-circuit current will do great damage to power equipment and imperil power systems. In order to control the short-circuit current， a design method for fault current limiter based on variable reactor is proposed. The fault current limiter is equipped with cores and variable air gaps， and thus can immediately switch off short-circuit current. Moreover， a genetic algorithm is introduced to optimize the design of the fault current limiter. Finite element analysis is used for simulation experiment on the fault current limiter. The analysis results show that the fault current limiter can offer high performance.

Orthogonal time frequency space (OTFS) is fully applied in high Doppler communication scenarios due to its good Doppler frequency bias and time delay adaptability.The channel estimation methods for OTFS systems have shortcomings such as high complexity and poor BER performance.A CNN-based channel estimation method for OTFS systems in the terrestrial-satellite scenario using a convolutional neural network (CNN) approach was proposed.Simulation results showed that the deep learning-based method outperformed the conventional method in terms of algorithm complexity and BER in the terrestrial-satellite scenario, thus demonstrating that deep learning is a promising tool for channel estimation in OTFS systems.

With the increasing mining depth of the mine, the high temperature and heat damage of the mining face is becoming more and more serious, and the phenomenon of spontaneous combustion of residual coal is particularly obvious, which seriously affects the safety production of the mine. In order to study the heat transfer law of fluid in porous media in goaf and analyze the influencing factors of porous media heat transfer, a porous media model of goaf is established by taking the 7271 working face of Yaoqiao Coal Mine as an example, and Fluent numerical simulation method is used to simulate the changes of gas concentration and temperature field in goaf under different wind speeds and different heat source positions. The results show that with the increase of wind speed, the range of “three zones” of spontaneous combustion in goaf moves to the depth of goaf, and the influence range of “three zones” of spontaneous combustion in air inlet side is larger than that in air return side. The closer the heat source is to the air inlet tunnel, the higher the overall temperature of the goaf. Increasing the air inlet tunnel wind speed can effectively reduce the internal temperature of the goaf and reduce the fluid heat transfer efficiency in porous media.

Objective: To solve the problem of low breaking rate and low kernel rate of walnut. Methods: According to the principle of walnut breaking shell, the material mechanism, breaking mechanism and transmission mechanism of walnut breaking shell were designed. Results: the breaking rate of walnut was 100% and the whole kernel rate was 77.58%. Conclusion: Walnut shell breaker designed by experiment is simple in structure, convenient in operation, economical and safe.

The analysis of microstructure deformation in polytetrafluoroethylene (PTFE) under heating or stretching conditions is essential to determine the failure mechanism. This study employed the synchrotron X-ray scattering technique to study microstructural deformation in PTFE under heating (25~300 °C), different strains at room temperature, and constant stress at variable temperatures (25~175 °C). The results indicate that the scattering the scattering intensity of PTFE increases with an increase in the temperature, and the imperfect crystals gradually melt. When PTFE was stretched under relatively lower strains at room temperature, its molecular chains tilted and lamellar crystals slid and rotated along the stretching direction. Moreover, when PTFE was stretched at constant stress and varying temperatures, its imperfect crystals gradually melted with an increase in the temperature and lamellar crystals were fractured by stress; the crystals were further fractured owing to the α-transition temperature caused by the movement of molecular chains in the amorphous regions.

Lung cancer is the malignant tumor with the highest incidence and mortality in China, and is prone to brain metastasis in the process of disease development, which seriously affects the quality of life and survival of patients. The treatment methods for brain metastasis of lung cancer include surgery, chemotherapy, whole brain radiotherapy, stereotactic radiosurgery, molecular targeted therapy, immunotherapy, anti-angiogenesis therapy, etc. It's one of the research hotspots to choose reasonable and effective treatment schemes for different patients. This paper reviews the research progress in the treatment of brain metastasis from lung cancer, to provide reference for selecting more reasonable clinical treatment for the patients.

The gait phase of dairy cows is an important indicator to reflect the severity of lameness. IThe accuracy of available gait segmentation methods was not enough for lameness detection. In this study, a gait phase recognition method based on Gaussian mixture model (GMM) and hidden Markov model (HMM) was proposed and tested. Firstly, wearable inertial sensors LPMS-B2 were used to collect the acceleration and angular velocity signals of cow hind limbs. In order to remove the noise of the system and restore the real dynamic data, Kalman filter was used for data preprocessing. The first-order difference of the angular velocity of the coronal axis was selected as the eigenvalue. Secondly, to analyze the long-term continuous recorded gait sequences of dairy cows, the processed data was clustered by GMM in the unsupervised way. The clustering results were taken as the input of the HMM, and the gait phase recognition of dairy cows was realized by decoding the observed data. Finally, the cow gait was segmented into 3 phases, including the stationary phase, standing phase and swing phase. At the same time, gait segmentation was achieved according to the standing phase and swing phase. The accuracy, recall rate and F1 of the stationary phase were 89.28%, 90.95% and 90.91%, respectively. The accuracy, recall rate and F1 of the standing phase recognition in continuous gait were 91.55%, 86.71% and 89.06%, respectively. The accuracy, recall rate and F1 of the swing phase recognition in continuous gait were 86.67%, 91.51% and 89.03%, respectively. The accuracy of cow gait segmentation was 91.67%, which was 4.23% and 1.1 % higher than that of the event-based peak detection method and dynamic time warping algorithm, respectively. The experimental results showed that the proposed method could overcome the influence of the cow's walking speed on gait phase recognition results, and recognize the gait phase accurately. This experiment provides a new method for the adaptive recognition of the cow gait phase in unconstrained environments. The degree of lameness of dairy cows can be judged by the gait features.

Objective To evaluate the osteogenic effect of concentrated growth factor (CGF) combined with deproteinated bovine bone mineral (DBBM) in site preservation using clinical and histomorphometric observations. Methods A total of 26 patients who needed extraction of affected teeth and received staged implantation after site preservation were selected. The patients were randomly divided into the DBBM group (Bio-Oss was implanted simultaneously after extraction) and CGF+DBBM group (CGF+Bio-Oss was implanted simultaneously after extraction), with 13 patients in each group, and both groups were covered with Bio-Gide collagen membrane. Cone beam computed tomography (CBCT) was performed preoperatively and 6 months later to measure the changes in alveolar bone height and width, and the bone specimens were drilled 6 months after site preservation during implant surgery for histological analyses. Results CBCT showed that the height and width of alveolar bone were absorbed 6 months after site preservation in the CGF+DBBM and DBBM groups, and the reduction in alveolar ridge width in the CGF+DBBM group was statistically less than the DBBM group (P

Objective The clinical characteristics and imaging information of insular glioma patients were collected to predict mutation status of isocitrate dehydrogenase 1 (IDH1). Methods A total of 596 patients with gliomas confirmed by postoperative pathology in The First Affiliated Hospital with Nanjing Medical University from January 2011 to June 2021 were enrolled, including 72 insular gliomas, 213 frontal gliomas, 165 temporal gliomas, 76 parietal gliomas, 28 and 29 midline gliomas. All patients were examined by MRI, fifteen glioma⁃related features were selected from the visually accessible rembrandt images (VASARI), including enhancement quality, enhancement proportion, non⁃enhancement proportion, necrosis proportion, edema proportion, cyst, thickness of enhanced margin, definition of the enhanced margin, hemorrhage, diffusion, deep white matter involvement, deep ventricle involvement, midline cross, T2⁃FLAIR mismatch, maximum diameter of tumor. Univariate and multivariate Logistic regression analysis were used to screen the predictive factors related to IDH1⁃mutant in insular glioma. The receiver operating characteristic (ROC) curve was plotted and area under the curve (AUC), sensitivity and specificity were calculated to evaluate the predictive power of MRI features for IDH1⁃mutant glioma. Results IDH1 mutation rate was higher in insular and frontal gliomas (P＜0.01, for all). WHO grade Ⅱ had the highest IDH1 mutation rate (P=0.008, 0.000), and grade Ⅳ had the lowest mutation rate (P=0.000). The IDH1 mutation rate in low⁃expression Ki⁃67 gliomas was higher than that in high⁃expression gliomas (P=0.000). Logistic regression analysis showed that weak enhancement (OR=35.671, 95%CI: 2.805-453.600; P=0.006), non⁃enhancement (OR=75.453, 95%CI: 2.881-1872.759; P=0.009), unlimited diffusion (OR=10.573, 95%CI: 1.043-107.175; P=0.046), no deep ventricle involvement (OR=187.601, 95%CI: 2.269-15507.607; P=0.020), T2⁃FLAIR mismatch (OR=47.536, 95%CI: 2.838-796.097; P=0.007) were independent predictive factors for IDH1 mutation in insular glioma. The AUC of enhancement degree, diffusion, deep ventricle involvement and T2⁃FLAIR mismatch for the diagnosis of IDH1⁃mutant glioma were 0.846 (95%CI: 0.748-0.944, P=0.000), 0.730 (95%CI: 0.609-0.850, P=0.001), 0.708 (95%CI: 0.584-0.833, P=0.003) and 0.745 (95%CI: 0.627-0.864, P=0.000). The combination of the 4 groups had the highest diagnostic efficacy, and the AUC was 0.961 (95%CI: 0.923-0.999, P=0.000). Conclusions Low grade insular glioma has a high IDH1 mutation rate. MRI features of weak enhancement and non⁃enhancement, unlimited diffusion, non deep ventricle involvement and T2⁃FLAIR mismatch contribute to noninvasive prediction of IDH1⁃mutant insular glioma.

[Introduction] The imported boiler tertiary superheater of Zhuhai power station which was designed and manufactured by Mitsubishi Heavy Industries has occurred tube failures frequently in recent years, the types were typical long-term overheating failures, the metallographic spheroidization were occurred and mechanical properties were declined, indicating that the furnace tube was in a long-term high temperature operation state. [Method] To find out the reasons of long-term overheating and to propose solutions, the thickness of oxide of tertiary superheater tubes was tested, the flow deviation and heat absorption deviation of tertiary superheater were studied. [Result] The residual creep life of 59% T91 tubes were less than fifty thousand hours, 39% T91 tubes were less than ten thousand hours, the residual creep life of 25% T23 tubes were less than fifty thousand hours, 9% T23 tubes were less than ten thousands hours. The flow deviation of the superheater header was 10.6%, the heat deviation of the tubes temperature in the width direction was 60 ℃. The problem couldn't be solved by replacing the new pipe section, the overall design Modification was required. [Conclusion] According to the above researches, the modification design by China-manufacturer was proposed. After the modification the flow deviation of the superheater header was reduced to 2.24% and the heat deviation of the tubes temperature in the width direction was reduced to 40 ℃. In addition, considering the working environment of the tertiary superheater, properties of the tube materials had been upgraded, the types of the material were reduced from 5 to 4, and the specification were reduced from 23 to 12, the procurement and maintenance costs were reduced.

In order to satisfy the requirements of the transmission rate and spectrum resource for various terminals and equipment in the satellite internet, a generalized approximation-based message passing optimization satellite receiver was designed.Considering the multi-user detection in the satellite network using the non-orthogonal multiple access, a factor graph was established based on the graph model, and the factor graph was used to analyze the message passing model of the system and a message passing algorithm was proposed.Based on the generalized approximate message passing method, the complexity of the traditional multi-user detector based on message passing was further reduced.Under satellite channel condition, generalized approximate messaging satellite receivers were studied.The simulation results show that the proposed algorithm can effectively solve the signal coexistence problem of multi-users, and reduce the computational complexity of the algorithm.

The existing researches on surfactant micellar solutions mainly focus on the formulation optimization and core flooding test, and the types and mechanisms of cleanup additives suitable for low permeability reservoir remain unclear. The flowback efficiencies of different types of surfactant micellar solutions were evaluated by core experiments, a multi-level pore-throat system micromodel characterizing pore-throat structures of low permeability reservoir was made, and flooding and flowback experiments of brine and surfactant micellar solutions of different salinities were conducted with the micromodel to show the oil flowback process in micron pores under the effect of surfactant micellar solution visually and reveal the mechanisms of enhancing displacement and flowback efficiency of surfactant micellar solution. During the displacement and flowback of brine and low salinity surfactant micellar solution, many small droplets were produced, when the small droplets passed through pore-throats, huge percolation resistance was created due to Jamin’s effect, leading to the rise of displacement and flowback pressure differences and the drop of flowback efficiency. The surfactant micellar solutions with critical salinity and optimal salinity that were miscible with crude oil to form Winsor III micro-emulsion didnot produce mass small droplets, so they could effectively reduce percolation resistance and enhance oil displacement and flowback efficiency.

With the rapid development of multimedia and communication technology,the amount of multilingual speech data on the Internet is increasing.Speech recognition technology is the core for media analysis and processing.How to quickly expand from a few major languages such as Chinese and English to more languages has become a prominent issue yet to be overcome in order to improve multilingual processing capabilities.This article summarizes the latest progress in the field of acoustic model modeling,and discusses breakthroughs needed by traditional speech recognition technology in the course of moving from single language to multi-languages.The latest end-to-end speech recognition technology was exploited to construct a keyword spotting system,and the system achieves favorable performance.The approach is detailed as follows:1)multi-lingual hierarchical and structured acoustic model modeling method;2)multilingual acoustic modeling based on language classification information;3)end-to-end keyword spotting based on frame-synchronous alignments.

This paper summarized the clinical data and nursing experience of a patient with gingival carcinoma treated by photodynamic therapy using bronchoscopy. Nursing plan consisted of various interventions such as basic nursing, psychological care, avoiding sunlight, illness observation, pain control, dietary care, Traditional Chinese Medicine nursing technique and health guidance before discharge. On the basis of clinical treatment, individualized nursing of integrated Traditional Chinese and western medicine is effective to improve the therapeutic effect, reduce the risk of post-operative complications and improve the patient satisfaction and post-operative quality of life. (本文回顾了1例经气管镜行光动力治疗牙龈癌患者的临床资料, 总结相关护理措施, 包括基础护理、心理护理、避光教育、病情观察、疼痛护理、饮食护理、中医护理和出院指导。在临床治疗基础上, 通过个体化中西医结合的护理措施干预, 有效提高了治疗效果, 改善患者生活质量, 降低并发症发生风险, 进一步提高临床护理满意度。)

Forestalling a large-scale reemergence of poverty is a basic task in the 14th Five-Year Plan period, which entails consolidating and expanding the achievements in poverty alleviation. This means we should manage the risks of people returning to poverty and enhance tiered and targeted assistance of various types to low-income residents, striving for a robust long-term mechanism of poverty reduction. In this paper, we first analyze the main challenges faced by consolidating and expanding the achievements of the battle against poverty in the new development stage. Among others, populations that have been lifted out of poverty falling back into it is complicated in causes, and industries in rural areas are short of sustainable development capacity. Other challenges remain, such as deficient rural medical services, drinking water safety in areas that have shaken off poverty, and outdated rural governance that is out of tune with the new situation. Subsequently, we summarize the basic logic of consolidating and expanding the achievements in poverty alleviation. We put forward three key tasks concerning increasing the institutional supply, relieving resources and environmental constraints, and stimulating endogenous impetus for those who have been lifted out of poverty. Lastly, we propose policy suggestions on consolidating and expanding the achievements in poverty alleviation from five aspects, including building an identification mechanism of low-income rural residents, promoting the performance of rural industries, improving governance capacity in rural areas, conducting rural doctors training programs, and ensuring drinking water safety.

When the mine long-distance belt conveyor adopts multi-point driving mode, the multi-motor synchronous control is adopted between the driving points at a long distance. Moreover, the multi-motor synchronous control strategy based on the traditional relative coupling control can not meet the synchronous requirements in the starting process when the rotational inertia of each motor is different, and the synchronous precision is not high when the steady state is disturbed. In order to solve the above problems, an improved relative coupling control method is proposed. A simple structured and easily implemented torque compensator is added on the basis of the traditional relative coupling control, the deviation between the actual rotating speed of each motor and the average rotating speed of all the motors is sent to a proportional controller for adjustment, and then the output result of the proportional controller is taken as a required torque compensation signal. In order to ensure the safe operation of the multi-motor drive system, the output torque of each motor after compensation is subjected to the same amplitude limiting. The simulation and experimental results show that the improved relative coupling control with torque compensator can realize the speed synchronization of multi-motors in the starting phase under different moments of inertia without affecting the dynamic response speed of the system. The proposed method ensures the system to have good anti-disturbance performance in steady state operation and high synchronization precision after disturbance.

In order to explore the effect of weld area and groove structure on the damage effect of laser irradiation on titanium alloy and ceramic coating, the experiment of continuous laser irradiation on welding seam and groove area of titanium alloy was studied, while the surfaces of the specimens were coated with or without anti-laser ceramic material. The following conclusions were obtained: the ceramic coating can protect the titanium alloy substrate from the damage of high power laser effectively; the laser resistance of ceramic coating on the welding seam area is weakened, but it still protects the titanium alloy effectively; the damage of laser on the edge and the corner structure of titanium alloy with groove structure is aggravated with the increasing of laser power density, and under the same laser density, the damage inside the groove is less than that outside, while that of corner is less than edge. Micromorphology results show that the ceramic coating undergoes a series of physical and chemical changes and phase transformation to absorb a large amount of thermal energy converted from luminous energy, which has a protective effect on the titanium alloy.

Conveyor belt deviation and coal stacking are common faults of belt conveyor in the coal mine. The traditional contact conveyor belt deviation or coal stacking detection methods can not meet the requirements of coal mine safety production in terms of durability, sensitivity and reliability. However, the detection effect based on the image processing method is greatly affected by image color information, which is prone to false identification. The belt conveyor deviation and coal stacking monitoring method based on 3D point cloud is proposed. The 3D point cloud data of the conveyor belt surface is collected by line laser binocular camera. The real-time monitoring of belt deviation and coal stacking is carried out by analyzing and processing the point cloud data. In terms of conveyor belt deviation monitoring, Euclidean clustering and random sampling consistency algorithm are used to filter redundant point cloud data, and extract edge data points of the conveyor belt. The mean central characterization value is used to characterize the degree of conveyor belt deviation, so as to reduce the influence of the shape change in the width direction of the conveyor belt on the monitoring. In terms of coal stacking monitoring, the equivalent height of coal flow is obtained by processing point cloud data. The height and width information of coal flow is characterized by the equivalent height, so that the coal stacking degree is evaluated in real-time. The test bed of the belt conveyor deviation and coal stacking monitoring system is built. The test results show the following points. When the speed of the conveyor belt is 0.5-3.0 m/s, the detection error of the edge point of the conveyor belt is − 2.84-1.26 mm, and the maximum error is only 2.84 mm. It shows that the system can reliably realize the function of deviation fault monitoring and accurately predict the deviation trend. Coal samples (14-41 kg, in increments of 1 kg) are stacked on the conveyor belt. When the coal mass is within the range of 14-24 kg and 28-41 kg, the coal stacking detection results are correct. There are detection errors in the range of 25-27 kg. The reason is that the coal sample quality in this range is close to the critical value of 27.6 kg for triggering the coal stacking alarm.

BackgroundThe extraction of uranium (U) and its alternative resources, such as thorium (Th) and plutonium (Pu), from seawater is essential to address the scarcity of terrestrial U resources. The development of a separation material with high adsorption properties is the key to solving this problem.PurposeThis study aims to reveal the adsorption behavior of actinides (U, Th, and Pu) on the surface of a two-dimensional metal material, antimonene.MethodsThe Hubbard U values, Ueff, were determined for the on-site Coulomb interactions of 5f electrons of U and Pu atoms using the linear response method. Furthermore, the adsorption energy, adsorption configuration, electronic structures, charge transfer, and highest occupied molecular orbital wavefunction of a U, Th, or Pu atom adsorbed on the surface of monolayer antimonene were analyzed using the DFT+U approximation. The variation of the adsorption rate with temperature was further calculated by the equilibrium adsorption rate equation.ResultsThe calculated Ueff values of U and Pu atoms are 2.24 eV and 2.84 eV, respectively. The Pu atom is energetically unfavorable to be adsorbed on antimonene (with a negative adsorption energy for each adsorption site), whereas the U and Th atoms exhibit strong chemical adsorption on its surface. Antimonene also offers abundant surficial stable adsorption sites for the U and Th adatoms. The most energetically stable sites for the U and Th adatoms are the B (Bridge)-H (Hollow) site and H (Hollow) site, with adsorption energies of 4.40 eV and 3.62 eV, respectively. The impurity states are generated in the band gap of antimonene upon the adsorption of the U or Th atom, and the strong p-d coupling between the U or Th adatom and antimonene in the impurity states contributes to the strong adsorption of the adatoms. The desorption temperatures of U and Th on the surface of antimonene reach 837 K and 660 K, respectively.ConclusionsThe results indicate that antimonene is an excellent two-dimensional adsorbent material for U and Th and has potential for several applications such as in the extraction of actinides from seawater.

In view of problems such as excessive dust concentration in working face and deterioration of working environment in mines caused by wide application of mechanized mining. We put forward technical means to optimize technical parameters of water injection and dust control in coal seam so as to increase water content of coal seam to be exploited. Using the simulation software COMSOL, the relationship between the process parameters such as water injection pressure and time and the infiltration effect of coal seam was studied. The third-order polynomial fitting function curve of wetting radius and water injection time under the condition of medium pressure water injection is obtained. The research results show that the infiltration effect of coal seam with medium pressure water injection is better. When the water injection pressure is 5 MPa, the optimal water injection duration is 5 h.

Lameness in dairy cattle could cause significant economic losses to the dairy industry. Detection of lameness in a timely manner is critical to the high-quality development of dairy industry. The traditional method is visual locomotion scoring by dairy farmers, which is low efficiency, high cost and subjective. The demand for automated lameness detection is increasing. The review was conducted to find out the current state and challenges of automatic lameness detection technology development and to learn from the latest findings. The current automatic lameness detection systems were reviewed in this paper mainly rely on five technologies or combinations thereof, including machine vision, pressure distribution measuring system, wearable sensor system, behavior analysis and classification; the principle, function and features of these technologies were analyzed. Machine vision technique is to extract feature variables (e.g. back arch, head bob, abduction, stride length, walking speed, temperature, etc.) from video recordings of cattle movement by image processing. Pressure distribution measuring system contains an array of load cells to sense gait variables, when dairy cattle are walking by. By using accelerometer with high frequency data collection, the gait cycle parameters can be extracted and used for lameness detection. By using wearable devices, the number of lying/standing bouts and their duration, the total time spent lying, standing and ruminating per day can be recorded for individual cattle. The lameness can also be detected by behavior analysis. Currently, most of these studies were in the stage of sensor development or validation of algorithm. A few studies were in the stage of validation of performance and decision support with early warning system. The challenges to apply automatic lameness detection system in dairy farm includes the difficulties of acquiring high quality data of lameness features, lack of techniques to detect early lameness, identification errors caused by individual gait differences among dairy cattle, difficulties to function well in unstructured environment and difficulties to evaluate the benefits. To accelerate the development of automatic lameness detection systems, recommendations are proposed as follows: ①promoting lameness data sharing and data exchange among dairy farms; ②developing individual-based lameness classification model; ③developing multifunctional smart station which can detect lameness, measure body condition score, weighing, etc; ④evaluating the significance of automatic lameness detection to the dairy industry from the perspective of animal welfare, environment and food safety.

Drilling operation is widely used in modern coal mine operation.Carbon monoxide gas (CO) is produced in coal seam during drilling operation, which leads to fire and CO exceeding accident.In this paper, an experimental platform for monitoring CO in coal borehole is built and Fourier infrared spectroscopy is carried out to analyze the law of production CO in coal seam during drilling from macroscopic and microscopic perspectives.The experimental results show that there is a certain amount of CO generated in the coal seam drilling operation, and the production of CO is proportional to the speed and temperature of the drill bit.In the coal sample cuttings after drilling, the contents of aliphatic group and oxygen-containing functional group are higher than the raw coal, indicating that the production rate of CO is higher than the consumption rate.Analysis shows that the CO produced during drilling operation is a mixture of oxidized carbon monoxide (O-CO) and carbon monoxide (S-CO) produced by the cracking of coal macromolecules.Among them, the O-CO generated during drilling operation mainly comes from oxygen-containing functional groups formed by oxidation of aliphatic functional groups such as -CH2 and -CH3, and pyrolysis occurs under the action of internal energy.S-CO is caused by coal's macromolecular fracture and the conversion of mechanical energy to thermal energy, leading to the pyrolysis of oxygen-containing functional groups in raw coal.

To accurately analyze the spontaneous combustion mechanism of coal seams in western Inner Mongolia area of China and the microscopic characteristics of coal spontaneous combustion, Jurassic experimental coal samples and Carboniferous comparative coal samples were selected to reveal the moisture in coal through industrial analysis of coal, static oxygen uptake and temperature programmed experiments. The influence of water, volatiles, ash, oxygen consumption and coal organic gas generation rate on coal spontaneous combustion tendency was studied. After measuring and finishing, it is known that the spontaneous combustion tendency of the Jurassic coal seam is positively correlated with the moisture and volatile matter content in the coal sample, but negatively correlated with the ash content. The static oxygen uptake of Jurassic coal samples exceeded 0.70 cm3/g and was higher than that of Carboniferous coal samples. At about 130 °C, the formation rates of CO and CO2 in Jurassic coal samples were 0.08 t/°C and 0.1 t/°C, CH4 is derived from the coal body itself, and the temperature rises to 120 °C to generate C2H6, and 150 °C precipitates C2H4. It indicates that the oxidation of the western Inner Mongolia Jurassic coal in the low-temperature oxidation stage is more severe.

Wi-Fi6 standard will be major Wi-Fi technology dominated for deployment after 2020. But to support increasing bandwidth requirements and number of access devices per year, Wi-Fi technology and throughput still need to be further developed and improved. This paper will introduce the key technology involved for latest IEEE802.11be standard discussion, describing the major changes on physical and MAC layer, particularly providing the analysis for multi-access point coordination, hybrid automatic repeat request and Wi-Fi full duplex mode. Finally, this paper will introduce the granted progress of latest 6 GHz applied by both new 802.11ax version and 802.11be with related Wi-Fi function impact.

Liposomes are microspheres that are similar to cell membranes. They have good sustained release, biocompatibility and targeting ability and can reduce the toxicity of encapsulated drugs. This article reviews the research progress of the use of liposomes in periodontal drug delivery systems and periodontal tissue engineering scaffolds. Liposomes have shown unique advantages and broad prospects in the field of periodontal drug delivery. Liposomes loaded with bioactive molecules and combined with periodontal tissue engineering scaffolds can improve the pharmacokinetics and local efficacy of these molecules. Modification of various extracellular matrix proteins on the surface of the scaffolds can promote the absorption of liposomes. Attachment of these proteins to the surface of the scaffold can reduce the requirement for bioactive molecules, improve the effective conversion rate and prolong the half-life of the scaffold in vivo. However, the development, clinical efficacy and safety evaluation of new liposomes still need to be further explored.

There are strict requirements for non-metallic inclusions in bearing steel, especially for Type-D inclusions.To analyze the formation mechanism of Type-D inclusions in high-frequency detection defects of GCr15 bearing steel bar sample in domestic steel plant and give the effective controlling measure, the inclusion evolution in bearing steel production process before and after optimization was investigated by ASPEX automatic scanning electron microscope.The results show that, the main formation mechanism of calcium aluminate Type-D inclusions present in the original process includes two aspects:one is the high basicity of refining slag, resulting in the high Ca O activity in slag.The other is the strong stirring in vacuum degassing (VD) process, providing good kinetic conditions for slag-steel reactions.The bearing steel production process is optimized from the basicity of refining slag and the vacuum degree of VD process.After optimization, the inclusions change from calcium aluminate to spinel type, and the formation of Type-D inclusions in bearing steel is reduced.Meanwhile, the high cleanliness of bearing steel is maintained.

In view of problem that global optimal path was difficult to determine due to disturbance of obstacle interval in process of path planning for coal mine search and rescue robot, optimal path planning algorithm for coal mine search and rescue robot based on gradient-coordinate rotation method was proposed. The robot first moves according to gradient-coordinate rotation method, then performs local path optimization according to existing motion path, and makes feasibility judgment on the planned local optimal path until there is no obstacle interval in the path. The simulation results show that the algorithm can make the coal mine search and rescue robot accurately plan the global optimal path from starting point to target point under the premise of avoiding obstacles, so as to improve rationality and efficiency of robot motion path planning.

In view of problems of technical difficulties, high cost and high voltage requirements for power electronic components in current high voltage wound-rotor motor using stator-side high voltage inverter for frequency conversion speed regulation, a rotor-side frequency conversion speed regulation technology for high voltage wound-rotor motor was proposed. The technology transfered power transformation from stator side to rotor side taking advantage of low voltage level on rotor side, frequency conversion speed regulation of high voltage wound-rotor motor was realized through general frequency converter. Mathematical model of vector control system for rotor-side frequency conversion was deduced, and adaptive full-order state stator flux linkage observer was designed. Speed identification was realized according to stator flux linkage observation. Matlab simulation and experimental results verify the correctness and feasibility of rotor-side frequency conversion speed regulation technology.

A 3D model of suspension support system of permanent magnetic suspension belt conveyor was established. Stability of permanent magnetic suspension support system under different magnetic conveyor belt shape, permanent magnet arrangement, permanent magnet shape and partial load condition were simulated. The results show that stability of groove-type magnetic conveyor belt is better than that of flat-type and V-type magnetic conveyor belts with stable bearing capacity. Stability and bearing capacity of conveyor belt are better when permanent magnet has groove-type structure. Partial load will increase deviation of magnetic conveyor belt. In order to effectively solve deviation problem of magnetic conveyor belt, an anti-deviation device for groove-type magnetic conveyor belt was designed. By installing auxiliary rollers on both sides of the groove-type magnetic conveyor belt, stability of the suspension support system of permanent magnetic suspension belt conveyor can be further improved.

In order to analyze the dynamics characteristic of the hip joint simulator which taking the 3HUS+ S spatial parallel mechanism as the core module,starting from the kinematics of parallel mechanism,the relationship between the velocity,acceleration of moving platform and the linear module slider and active branched- chains are established. By the forces and torques of the centroid of the moving platform,active branched- chains and linear module,the dynamics model is established based on the principle of virtual power. The driving torques and powers of the linear module are obtained by simulating on the dynamics model,a reference for the simulator in the analysis of dynamics characteristics and research of control strategy is provided.