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An effective method for the internal interaction within modeling reality systems is provided by graphs; however, they have been unable to effectively display and capture the high-order heterogeneity that widely exists between multiple entities. Hypergraphs have been recognized for their ability to surpass the limitations imposed by low-order relationships. Hypernetwork link prediction, which involves predicting unknown hyperlinks based on the observed hypergraph structure, has increasingly become a hot topic in network science due to its capacity to fully describe the association patterns of complex systems. Existing methods typically design reasoning models for the entire topology, often overlooking the implicit aggregation characteristics within the network, which leads to an incomplete prediction of hyperlink categories. To address these issues, a coordination matrix minimization model based on hypergraph spectral clustering parser (SCL-CMM) was proposed. Initially, higher-order hypernetworks were mapped into heterogeneous hypergraphs with certain semantics. Subsequently, the spectral clustering parser was employed to extract the structural features of hyperlinks. The original hypergraph was reconstructed into multiple homoprotonic graphs, and the distribution of potential hyperlinks was inferred within the observation space of the subgraph, rather than the entire adjacency space, in order to restore the complete hypernetwork structure. This method federated learned the structural characteristics and aggregation attributes of hypernetworks to model the high-order nonlinear behavior of each subgraph, thereby solving the problems of single category and low precision in heterogeneous hypergraphs link prediction. Extensive comparative experiments were conducted on nine real datasets, demonstrating that this method significantly outperformed existing methods in terms of AUC score and recall rate.

Objective To investigate the efficacy and safety of ofatumumab in the treatment of neuromyelitis optica spectrum disorders (NMOSDs). Methods The clinical data of 25 patients with NMOSDs hospitalized in The First Affiliated Hospital of Zhengzhou University from April 2022 to March 2023 and treated with ofatumumab were retrospectively analyzed. They were divided into 2 groups, Group A with 12 cases receiving regular medication, and Group B with 13 cases receiving medication based on the percentage of CD19+B lymphocytes. Annual relapse rate (ARR), the number of relapses, the frequency and time of relapses, and the symptoms of relapses were calculated before and at one year of medication. The neurological function was assessed by Expanded Disability Status Scale (EDSS) before and at one year of medication. The adverse drug reactions were recorded during medication. Results After one year treatment with ofatumumab, 3 patients (12%) experienced recurrence. One patient in Group A experienced recurrence twice, one month and 5 months after treatment, respectively. At the second recurrence, the percentage of CD19+B lymphocytes was 2.80%. Two patients in Group B experienced recurrence, one patient relapsed twice at 2 and 6 months after medication. The percentage of CD19+B lymphocytes was 0.80% and 0.21%, respectively; another patient relapsed once at 2 months after medication. At the time of recurrence, the percentage of CD19+B lymphocytes was 0.70%. There was a statistically significant difference in ARR before and after one year treatment (F = 29.061, P = 0.000). After one year's treatment, the ARR of Group A (t = 13.215, P = 0.001) and Group B (t = 19.259, P = 0.000) was decreased than before. There were 8 cases of the injection site pain, 3 cases of fever after injection, and one case of headache after injection. There were no serious adverse reactions such as disability and death, and EDSS scores were not increased. Conclusions Continuous administration of ofatumumab every 3 months or based on the percentage of CD19+B lymphocyte can reduce recurrence. Combination with corticosteroids should be alert to the risk of infection.

The problem of differential protection maloperation caused by inrush current during no-load closing of transformer has not been completely solved so far. To solve this problem, a method using long short-term memory (LSTM) neural network to identify inrush current and fault current is proposed. First, the simulation model of no-load closing and internal fault of transformer is built on the PSCAD software platform, and a large amount of three-phase current instantaneous sampling data is generated through simulation as the sample set to train the neural network. Then, the LSTM neural network model is built and trained by using the Keras platform. Finally, the new simulation data and fault recorder data is used to test the trained LSTM neural network. The results show that the LSTM neural network can quickly and accurately distinguish the inrush current and fault current under various conditions, which proves the effectiveness of the proposed method.

Objective To investigate the age-related changes of the mandibular third molar root pulp visibility in individuals in East China, and to explore the feasibility of applying this method to determine whether an individual is 18 years or older. Methods A total of 1 280 oral panoramic images were collected from the 15-30 years old East China population, and the mandibular third molar root pulp visibility in all oral panoramic images was evaluated using OLZE 0-3 four-stage method, and the age distribution of the samples at each stage was analyzed using descriptive statistics. Results Stages 0, 1, 2 and 3 first appeared in 16.88, 19.18, 21.91 and 25.44 years for males and in 17.47, 20.91, 22.01 and 26.01 years for females. In all samples, individuals at stages 1 to 3 were over 18 years old. Conclusion It is feasible to determine whether an individual in East China is 18 years or older based on the mandibular third molar root pulp visibility on oral panoramic images.

Boron neutron capture therapy(BNCT) is a binary targeted radiation therapy in which neutron does not directly provide tumor dose. The dose produced by the 10B(n, α)7Li capture reaction will be deposited in tumor cells by using targeted 10B agents. Therefore, understanding the biological distribution of 10B agents in the blood, tumor and normal tissue is essential for BNCT. 4-borono-L-phenylalanine(BPA) is the mainly used 10B agent in BNCT clinical trials worldwide. In order to support and facilitate the preparation of BPA-based BNCT clinical trials, information on the structure, physicochemical properties, cellular uptake mechanisms and human biological distribution of BPA are summarized in this paper.

In view of the heat dissipation of electronic components with high heat flux, five phase change heat transfer cold plates with different structures and processing methods were designed, the effects of cold plate structural parameters, heat flux, refrigerant flow rate, and heat source layout on heat transfer performance, resistance of cold plate, and the pump power consumption were experimentally studied. The results show that the designed perforated cold plate has excellent heat transfer performance. The designed perforated cold plate maintains a temperature difference of less than 25 ℃ between the heat source surface and the refrigerant inside the cold plate when dissipating a total heat output of 5 000 W and a heat flux of 38 W/cm2, with cold plate resistance less than 30 kPa and pump power consumption less than 35 W. The processing method of cold plate has a significant influence on its heat transfer effect. The cold plate should adopt integrated design as far as possible to reduce the link of heat transfer and avoid the contact thermal resistance caused by the chimerism of different materials. When multiple heat sources have different heat flux densities, placing the higher heat flux heat source closer to the inlet of the cold plate achieves better heat transfer efficiency.

A mine intrinsically safe audio and video recorder is designed. The device is based on 5G SOC processor, and adopts the photosensitive sensor + white light/infrared laser fill light + intrinsically safe circuit scheme. Under the environment of low illumination, full black or confined space, it can collect, compress, store and display 4K high-definition video images, and transmit the collected audio and video data in real time. The recorder has the characteristics of high imaging quality, long shooting distance and low power consumption in low illumination environment; it supports TCP/IP, UDP, RTP, ONVIF, GB28181 and other protocols. In addition to serving as an underground information record, it can also assist the emergency headquarters in carrying out rescue operations in time. The test results show that the picture resolution of the recorder is 10 688×6 012, the video resolution is 2 560×1 440, the visual distance is 20 m, the data packet loss rate is about 0.068%, the delay is about 15.85 ms, and it can achieve continuous video recording for 9 hours or continuous video playback for 4 hours.

MIS6 to MIS5 is a typical transition period from glacial to interglacial periods. The climate elements of MIS5 are similar to that of the current warm period, and studying its evolution process can better understand the climate change process of the current warm period and the future climate change trend. Based on modern spore–pollen and meteorological data, as well as stratigraphic spore–pollen and particle size indicators from the Yinchuan Basin in the monsoon margin area, the locally weighted average partial least squares method (LWWA-PLS) reconstruction results are considered to be the most robust after the selection of the training set, screening of the master climate parameters, cross-validation of the five reconstruction models, regional comparison, significance testing, and ecological interpretation. The climatic evolution from MIS6 to MIS5 can be divided into six stages. 157 to 131 ka, the climate was cold and humid, where wet and cold-loving arborvitae vegetation developed, with the average annual precipitation (Pann) being 424.99 mm and the average temperature in July (TJuly) 22.58 ℃. 131 to 119 ka, the climate turned wet and warm, and warm-loving trees and herbs developed; the Pann was 410.95 mm, and the TJuly was 23.62 ℃. 119 to 111 ka, the Pann was 369.50 mm, and the TJuly was 22.53 ℃; cold-loving herbs and trees developed in a cold and dry climate. 111 to 98 ka, the Pann is 378.39 mm, and the TJuly is 22.86 ℃; warm-loving trees account for a higher proportion in the early stage, and the number of cold-loving trees increased in the late stage; the climate was overall dry and warm, and the temperature increased first and then decreased. 98 to 85 ka, the Pann was 278.24, and the TJuly was 22.01 ℃; the overall climate was the driest and coldest, and cold-loving trees developed well. 85 to 78 ka, the Pann was 364.21 mm, and TJuly was 23.45 ℃; the climate turned warm and humid, and trees and herbs developed in this period. The reconstructed climate parameters' ensemble empirical mode decomposition (EEMD) results respond well to the 23 ka precessional cycle. Comparison with the mid- and high-latitude geologic record of the Northern Hemisphere suggests that solar radiation-influenced climatic variability in the North Atlantic primarily drives changes in the East Asian monsoon through the westerly wind circulation as well as the oceanic transport zone, which in turn influences climatic change in the Yinchuan Basin.

This paper gives a full description of development of foreign air-to-air missiles in 2022. It pre-sents the latest advancement of AIM-9X, AIM-120, Modular Advanced Missile, ASRAAM, IRIS-T, FCAAM, Meteor, innovative missile technologies, R-37M, Astra BVRAAM, Turkish new air-to-air missiles. In the end, the paper summarizes the new development features of air-to-air missiles.

When the pressure vessel of supercritical carbon dioxide energy conversion system breaks, very complex ejection phenomena will occur, and its critical flow characteristics need to be studied urgently. Based on Moody’s and Henry-Fauske’s two-phase critical flow analysis method for one-component mixture, SCRSAP-LOCA program was opened in Modelica language. This program was divided into simple vessel module, phase judgment module, break injection calculation module and physical property query module according to the calculation function. Then, the flow phenomena in different stages of supercritical carbon dioxide injection process were modeled and analyzed, and compared with the existing experimental data to verify, and the effects of different initial conditions in the vessel on the injection process were analyzed. The results show that the program calculation results agree well with the experimental data. The error between flow rate and pressure is within 23%. The mass flow rate at the fracture calculated by Moody’s model is closest to the experimental value. The flow rate calculated by Henry-Fauske’s model is about 15%-25% higher than the experimental value. The emission of carbon dioxide in pressure vessel can be roughly divided into three stages: Fast pressure relief stage with high mass flow, stable pressure relief stage with medium mass flow and uniform pressure relief stage with low mass flow. The break flow and pressure curve of the vessel show a stepped decrease. The emission behavior of supercritical carbon dioxide in vessels varies greatly at different initial temperatures and pressures. When the initial temperature in the pressure vessel is 297 K and the initial pressure increases from 10 to 20 MPa, the initial ejection mass flow in the first stage is larger, the pressure in the vessel is lower at the beginning of the second stage and the critical two-phase ejection duration is longer. When the pressure in the pressure vessel is 15 MPa, the increase of the initial temperature will significantly reduce the fluid density, accelerate the decrease of the free liquid level and shorten the critical discharge time of two-phase. As the initial temperature increases further, the flow and pressure curves become smoother as supercritical carbon dioxide approaches the gaslike region. In addition, phase transitions occur in the vessel during the ejection process and liquefied carbon dioxide deposits at the bottom of the vessel due to the difference in density. The research results can provide reference for the analysis of supercritical carbon dioxide emission characteristics in pressure vessel, and provide support for the research of leakage accident process and safety analysis and evaluation of supercritical carbon dioxide energy conversion system.

The volatile components of three different colored rices were characterized by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS). A total of 64 peaks were detected, and 44 volatile compounds were identified. White rice liberated a high concentration of 2-mhyl-2-propenal, 3-methylbutanal, heptanal monomer and four unknown components after cooking. Red rice liberated a high concentration of heptanal (monomer and dimer), pentanal, 2-butylfuran, amyl aldehyde, furan, (E)-2-heptenal (monomer and dimer), octanal (monomer and dimer), (E)-2-octenal, n-nonanal (monomer and dimer), isopentyl alcohol, decanal, ethyl acetate, 2,3-butanedione, 2-pentylfuran, and 10 unknown compounds. Black rice released a high concentration of 2-pentanone, 2-hexenal, 3-butenenitrile, 3-methyl-1-pentanol, 1-octene-3-one, furfuryl alcohol, 2-methyl-ethyl butyrate, benzaldehyde, phenylacetaldehyde, propanedioic acid, dietyl ester, and two unknown components. After cooking, the number of aroma compounds in the three colored rices increased. In conclusion, headspace-gas chromatography-ion migration spectrometry can well characterize the aroma of different colored rices before and after cooking, making it easier for consumers to choose rice.

For preparing an intermetallic compound coating with Ni2Al3 as the main phase，the Ni，Al and Al2O3 powders were mixed uniformly based on a mass ration of 20 ∶6 ∶5，and the mixed powders were sprayed onto the 45 steel surface to form a Ni-Al pre-coating by low pressure cold spraying method.Subsequently，the Ni-Al pre-coating was kept in an argon atmosphere at 520 ℃for 12 h.The morphology and phase structure of the as-prepared coating were analyzed and characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM).In addition，the bonding force as well as the sliding friction and wear performances of the coating were tested.Results showed that after thermal treatment，the pre-coating changed into a Ni2Al3 intermetallic compound coating，which presented superior anti-friction and wear-resisting properties.The driving force for the transformation of Ni and Al solid phases into intermetallic compound was the combined effect of thermal energy provided by heat treatment and deformation energy of the powders resulting from strong plastic deformation.

In this study, magnetic metal organic framework composites as capture probe and immunofunctionalized gold nanoparticles as signal probe were used to develop a rapid colorimetric method for the detection of Listeria monocytogenes. Under optimal conditions, the visual detection limit for L. monocytogenes was 1.2 × 103 CFU/mL. The results of ultraviolet spectroscopy showed a good linear relationship in the range of 1.2 × 101‒1.2 × 108 CFU/mL (Y = 0.519 ‒ 0.043X, R2 = 0.978), the detection limit was as low as 0.45 CFU/mL, and the intra-batch coefficient of variation of all concentration gradients was between 0.31% and 1.30%. The recoveries for spiked chicken breast were 91.1%‒108.7% with coefficient of variation less than 7.4%, and the result was consistent with that of the plate counting method. In conclusion, the proposed assay is rapid, accurate sensitive, and highly applicable to the detection of foodborne pathogens.

Accurate calculation of harmonic impedance is the premise of harmonic control and reasonable division of harmonic responsibility. The existing harmonic impedance estimation methods should meet the conditions that the background harmonic fluctuations are small and the customer harmonic impedance is much larger than the utility harmonic impedance. However, the use of a large number of power electronics in power system makes those conditions are not be satisfied. Therefore, a utility harmonic impedance estimation method based on mutual information and data optimization is proposed. Firstly, the utility harmonic currents are solved by independent component analysis (ICA), and the data segments with small mutual information between the harmonic currents at the point of common coupling (PCC) and the utility harmonic currents are selected. Finally, the harmonic impedance of the screened data segment is estimated using the characteristic of zero covariance between the harmonic current at the PCC and the harmonic voltage on the utility. The effectiveness of the proposed method is tested by simulation and actual case analysis. Compared with existing methods, the proposed method is more accurate and widely applicable when the customer harmonic impedance is not much larger than the utility harmonic impedance.

Mangroves, which have extremely high primary productivity, are efficient coastal blue carbon ecosystems. Aboveground biomass (AGB) is an important component of vegetation carbon pools. Thus, accurate estimation of mangrove AGB is critical for studying carbon cycle and climate change. While the practical significance and application of information obtained on mangrove AGB in China is apparent, studies of this nature in China at a national scale have rarely been reported. Remote sensing technology is convenient, efficient, has a wide observational range, and can be used for large-scale ecosystem monitoring. Canopy height is a structural parameter that is positively correlated with the AGB of vegetation. The Global Ecosystem Dynamics Investigation (GEDI) spaceborne Light Detection and Ranging (LiDAR) satellite, launched in recent years, is able to obtain vegetation canopy height. This study employed forest canopy height derived from GEDI satellite-based LiDAR and an allometric equation based on the allometric theory to estimate mangrove AGB in China in 2019, and the quantitative and spatial distribution of mangrove biomass and their main influencing factors were analyzed. The results showed that the total and mean AGB of mangroves in China in 2019 were about 1,974,827 t and 73.0 t/hm2, respectively. Guangdong-Hong Kong-Macao area showed the largest total mangrove AGB, reaching 843,836 t. The mean values of AGB in each province (region) with mangrove ecosystems nationwide ranged from 53.3 to 92.1 t/hm2, of which the largest was found in Hainan Province, reaching 92.1 t/hm2. In Hainan, Taiwan, and Fujian provinces, mean mangrove AGB was higher than the national mean. Considering nature reserves, the mean AGBs of mangroves in Neilingdingdao-Futian and Mai Po mangrove nature reserves in Shenzhen Bay in the Guangdong-Hong Kong-Macao area and Dongzhaigang mangrove nature reserve in Hainan province were relatively high, with values greater than 110 t/hm2. The accumulation and distribution of mangrove AGB in China are affected by latitude and anthropogenic factors. This study provides a comprehensive analysis of mangrove AGB in China based on remote sensing and an allometric equation and can provide a database and technical reference for estimating carbon storage in mangrove ecosystems. It will also contribute to the implementation of ecological restoration and protection measures for coastal mangroves, as well as carbon emission control in China.

Accurate mangrove biomass measurement is necessary for the management and protection of mangrove ecosystems. Sonneratia apetala was the first high-quality mangrove species to be introduced for mangrove restoration in China. Compared with other mangrove species, Sonneratia apetala has higher productivity and can store large amounts of carbon in its living biomass. However, accurate depiction of the single-wood canopy of Sonneratia apetala is challenging because of its high clumping density and intricate canopy structure. While traditional satellite remote sensing focuses on regional or larger-scale monitoring needs, the newly emerged Unmanned Aerial Vehicle (UAV) remote sensing has significant advantages for monitoring mangroves at finer scales. However, few studies have used UAV data for mangrove biomass analyses. In this study, we successfully used consumer-grade UAV data to estimate the height and aboveground biomass (AGB) of Sonneratia apetala on Qi'ao Island, Zhuhai, Guangdong Province. We used a variable window filter algorithm to detect the treetops. Individual tree canopy segmentation was performed using the seed region-growing algorithm. Additionally, we constructed a regression equation for height (H) and diameter at breast height (DBH) of Sonneratia apetala in the study area and optimized the traditional allometric equation. Finally, mangrove AGB was estimated at the tree level using the optimized allometric equation, and the results indicated that the AGB of Sonneratia apetala could be accurately extracted using UAV images. The accuracy of the tree delineation was 67%, the correlation between H and DBH was DBH = 2.2726H-6.4415, and the correlation coefficient R2 was 0.8713. The aboveground mass of a single wood of Sonneratia apetala in the study area ranged from 29.60 to 388.44 kg, with a mean value of 145.72 kg and a total aboveground mass of 368.97 t. Partial spatial clustering was observed in the distribution of the aboveground mass of Sonneratia apetala in the study area, with a Moran's I index value of 0.594. The aboveground mass of Sonneratia apetala at the edge of the area and in the window part of the area was found to be smaller, mainly for two possible reasons. First, the natural death of Sonneratia apetala in part of the study area created a window, but its surrounding seedlings were still in the biomass accumulation stage. Second, the aboveground mass of Sonneratia apetala at the edges of the study area is often lost due to its vulnerable nature and anthropogenic factors. The average number of Sonneratia apetala in each quadrat was 6.3 and the AGB in the study area ranged from 2.99 to 247.24 t/hm2, with a mean value of 92.14 t/hm2. The estimated AGB based on UAV data was consistently lower than that generated from field data. The methods described in this study offer the possibility of easily repeatable, low-cost UAV surveys, providing a faster and more economical approach for monitoring mangrove forests than traditional ground surveys. These results may assist in decision-making regarding ecological monitoring, resource use, mangrove introduction, and scientific advancement of mangroves in China.

The underwater target shell has clear technical requirements for the performance of the superhydrophobic microstructure surface coating which has great influences on the navigation resistance of the underwater target. Polyurethane hydrophobic resin and fluorine modified SiO2 particle filler were synthesized according to the synthetic principle of superhydrophobic coating. Three kinds of superhydrophobic microstructure surface coatings including those based on polyurethane hydrophobic resin, silicon - containing resin and fluorine - containing resin were prepared, and the main components and preparation process of each coating were confirmed. Furthermore, the performance of the three superhydrophobic coatings was tested and evaluated, and their performance indicators were compared and analyzed, such as the thickness, hardness, adhesion, static and dynamic hydrophobic angles, surface microstructure, wear resistance, seawater immersion resistance, salt spray resistance and thermal stability. Results showed that the F660 + 8%SiO2 silicone - containing superhydrophobic coating possessed the best comprehensive performance. This would provide a basis for further resistance test of underwater target shell with superhydrophobic microstructure surface coating.

Objective To investigate the effects of miR-760 on the proliferation, invasion and migration of esophageal squamous cell carcinoma (ESCC) cells through targeted regulation of basic leucine zipper ATF-like transcription factor 3 (BATF3). Methods The cancer tissues and adjacent tissues of ESCC patients were collected, and normal human esophageal squamous epithelial cells Het-1A and human ESCC cell lines EC9706, KYSE150, ECA109, TE-10 were cultured in vitro. RT-qPCR was used to detect the expression of miR-760 and BATF3 mRNA. miR-760-mimics were transfected into TE-10 cells for up-regulating the expression of miR-760. CCK-8 method was used to detect cell proliferation and Transwell chamber was used to detect cell invasion as well as migration. Western blot was used to detect the expression of proliferation-related proteins cyclin D1, p21 and epithelial-mesenchymal transition related proteins MMP2, vimentin, and E-cadherin. Dual luciferase reporter gene experiment was used to confirm the targeting relationship between miR-760 and BATF3. Results Compared with the adjacent tissues and Het-1A cell, the expression of miR-760 was significantly reduced in ESCC tissues and in cell lines, while the expression of BATF3 increased (P＜0.05). The TE-10 cells with the highest expression of miR-760 were selected for subsequent experiments. Over-expression of miR-760 reduced the activity of TE-10 cells and the counting numbers of invasion and migration cells(P＜0.05). The expression of cyclin D1 and vimentin proteins increased the expression of p21 and E-cadherin proteins (P＜0.05). The results showed that miR-760 negatively regulated the expression of BATF3 (P＜0.05). Up-regulation of BATF3 expression reversed the inhibitory effects by over-expression of miR-760 on the proliferation, invasion and migration of TE-10 cells(P＜0.05). Conclusions Over-expression of miR-760 may inhibit the proliferation, invasion and migration of ESCC cells, which may be related to the targeted inhibition of BATF3 expression.

The plate-type fuel assembly with the advantages of high specific power of active zone and compact structure has been widely adopted in many research reactors and material irradiation test reactors. The narrow rectangular channel in platetype fuel assembly has the geometric characteristics of large aspect ratio, resulting in large gradient and steep distribution of velocity in the height direction. When the subcooled boiling occurs, the bubble behavior near heated wall will be affected, and the bubble sliding phenomenon has a great influence on the boiling heat transfer. In this paper, a wall heat flux distribution model considering the sliding heat flux was built and quenching heat flux was redefined as the sensible heat released by the solid wall under the dry spot. The bubble stress analysis model and sliding model based on theoretical and semi-empirical expressions were established to calculate essential auxiliary parameters including bubble departure diameter, lift-off diameter and sliding distance. A wall boiling model suitable for upward flow boiling in the narrow rectangular channel was developed. After that, the numerical simulations under different operating conditions were performed against the Nuthel flow boiling experiments in narrow rectangular channels for model verification. The results show that the model developed in this paper can better predict the wall superheat degree of upward flow boiling in the narrow rectangular channel under medium and low pressure conditions in the range of 1-4 MPa. Compared with the RPI model, the wall temperature calculated by the developed model in this paper is much higher, and the maximum error of wall superheat in the boiling region decreases from 80% to 17% in the simulated conditions, indicating that the wall boiling model considering the sliding heat flux can describe the flow and heat transfer characteristics of upward flow boiling in the narrow rectangular channel more accurately. As for the heat flux distribution, the sliding heat flux and single-phase convective heat flux calculated by developed model take up significant fraction, and evaporation heat flux is less significant. The quenching heat flux, defined by the reconstructed expression, is almost negligible, which demonstrates that the sensible heat released by the solid wall under the dry spot has little influence on the overall heat transfer process. In RPI model, however, evaporation heat flux accounts for the majority of the total heat flux in the boiling region. Lower fraction of heat flux allocated to evaporation heat flux leads to less evaporation rate and predicted void fraction.

BACKGROUND The Wunugetushan copper-molybdenum deposit located in the northwest of the Erguna—Hulun fault is a large porphyry copper-molybdenum deposit. Magmatic rocks are widespread in the mining area. OBJECTIVES In order to determine the emplacement age and tectonic setting of ore-hosting surrounding rock and ore-forming parent rock, and to discuss the petrogenesis and metallogenic dynamics. METHODS Zircon U-Pb isotopes and zircon Lu-Hf isotopes of rocks were studied by laser ablation multi-collector inductively coupled plasma mass spectrometry (LA-MC-ICP-MS) and laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS). RESULTS (1) The zircons in the study area have a high content of REE with strong enrichment of HREE, δEu negative anomaly and δCe positive anomaly, and the REE distribution curves are left-inclined. (2) The anisomitic monzogranites are the ore-hosting rocks with a weighted average value of 200.96±0.88Ma, indicating that the rock mass was formed in early Jurassic. Zircon εHf(t) ranges from 0.1 to 5.8, single-stage Hf model ages (TDM) range from 643Ma to 882Ma, and two-stage Hf model ages (TDMC) range from 874Ma to 1235Ma. (3) The rhyolite porphyritic lavas are the ore-forming parent rocks with a weighted average value of 179.58±0.91Ma, indicating that the rocks formed in the Early Jurassic. Zircon εHf(t) ranges from 4.3 to 6.6, single-stage Hf model ages (TDM) range from 570Ma to 663Ma, and two-stage Hf model ages (TDMC) range from 802Ma to 952Ma. CONCLUSIONS The zircon Lu-Hf isotopic characteristics of the anisomitic monzogranites indicate that the magma source is a mixture of mantle and a small amount of ancient crust. The magma source area of the rhyolite porphyritic lavas is dominated by mantle-derived materials. The transition evolution process from crust source to mantle source from host rock to metallogenic parent rock is revealed.

In partial discharge(PD) detection, due to the simultaneous and constantly changing phenomenon of multiple discharge sources and on-site interference sources, it is difficult to effectively separate and identify multiple PD sources. An efficient adaptive efficient adaptive online data stream clustering algorithm (EAOStream) is proposed. The algorithm uses natural neighborhoods to create K-dimensional (KD) trees to improve the efficiency of querying neighbors. That is, the adaptive neighborhood radius and the area density are obtained through the characteristics of the flow data, which can search locally and form clusters, and realize the real-time online separation of multiple local discharge sources. The superiority of EAOStream is verified in the artificial data set and the real data set. After comparing EAOStream with the traditional DenStream and SE-Stream algorithms, it is applied to the pattern recognition of gas-insulated substation faults. Experimental test results show that the clustering accuracy of EAOStream in the real network intrusion detection, the forest cover type, and the multi-source PD signal data sets reaches 95.28%, 98.47%, and 97.23%, verifying the practicability and effectiveness of the algorithm in fault diagnosis of gas-insulated substations.

The community-based chronic disease containment in China is still in its infancy, and there is a lack of a complete system for practical implementation with tertiary and secondary or primary hospitals collaboratively involved. We systematically summarized the development of chronic disease management in China, then analyzed the essentials of three major foreign chronic disease management models (chronic care model, innovative care for chronic conditions framework, and chronic disease self-management program) and chronic disease management experiences of Finland, the U.S., Australia, Japan with a focus on management ideas, systematic structures, and operable approaches. With these foreign models and experiences as a reference, we developed a general practice plus compact regional medical consortium-based chronic disease management model used in Lishui Town with complexity science and analysis for resource integration, against the backdrop of promoting the development of the compact county medical consortium and contracted family doctor services. We expect that our study could provide new ideas for the research on chronic disease containment in China's primary care.

Objective To analyze the relationship between the preoperative relative blood glucose ratio and the safety of cerebrovascular bypass of ischemic moyamoya disease (MMD) patients. Methods A total of 178 patients with ischemic MMD who were hospitalized in Department of Neurosurgery of Qilu Hospital of Shandong University from December 2016 to December 2019. A total of 186 cases underwent superficial temporal artery⁃middle cerebral artery (STA⁃MCA) bypass. The fasting blood glucose and glycated albumin of all patients at admission were recorded to calculate the relative blood glucose ratio. After STA⁃MCA bypass, the incidence of postoperative complications was counted. Univariate and multivariate Logistic regression were used to analyze the risk factors of postoperative complications of ischemic MMD. Results 186 cases were divided into 4 groups based on relative blood glucose ratio, Q1＜0.404, Q2 0.404-, Q3 0.456-, Q4≥0.534. The proportion of right surgery side in Q1 group was higher than that in Q3 group (χ2=4.762, P=0.029) and Q4 group (χ2=22.087, P=0.000), while the proportion of right surgery side in Q2 group (χ2=16.331, P=0.000) and Q3 group (χ2=7.355, P=0.007) was higher than that in Q4 group. The incidence of mild complications in Q1 group (χ2=6.389, P=0.011) and Q2 group (χ2=4.040, P=0.044) was higher than that in Q4 group. The incidence of postoperative complications was 28.49% (53/186), of which 8.60% (16/186) were severe type and 19.89% (37/186) were mild type, including transient neurological dysfunction 97.30% (36/37), subdural hemorrhage 2.70% (1/37). Logistic regression analysis showed that the relative blood glucose ratio increased (OR=1.484, 95%CI: 1.071-2.058; P=0.018), hypertension (OR=3.696, 95%CI: 1.805-7.569; P=0.000), operative interval＜2 months (OR=2.186, 95%CI: 1.041-4.590; P=0.039) was risk factors for postoperative complications. Conclusions In order to reduce the incidence of postoperative complications in patients with ischemic MMD, the operation interval after infarction can be extended to 2 months, and the preoperative relative blood glucose ratio should be closely monitored and the perioperative blood pressure should be controlled.

Objective To investigate the effect of RhoC expression in vascular endothelial cells on the proliferation and invasion of myeloma RPMI8226 cells and its possible mechanism. Methods RhoC shRNA lentivirus vector was constructed and transfected into myeloma vascular endothelial cells (MVECs) and human umbilical vein endothelial cells (HUVECs). The effects of conditioned medium on the proliferation, cell cycle and invasion of RPMI8226 cells were detected by CCK-8 test, flow cytometry and Transwell test. The expression of CDK, CyclinD1, AKT, PI3K, MMP2 and MMP9 were detected by Western blot. Results The expression of RhoC in MVECs and HUVECs were downregulated. The proliferation and invasion of RPMI8226 cells in RhoC shRNA group were lower than those in negative control group, and the cell cycle was blocked in G0/G1 phase (P < 0.05). The expressions of CDK, CyclinD1, AKT, PI3K, MMP2 and MMP9 in RhoC shRNA group were lower than those in negative control group (P < 0.05). Conclusion The expression of RhoC in MVECs can regulate the proliferation and invasion of myeloma RPMI8226 cells, and the mechanism may be related to the participation of CDK, CyclinD1, AKT, PI3K, MMP2 and MMP9.

Aiming at the problem that the existing research on industrial security mainly focuses on industrial ethernet and lacks the research on serial link protocol protection,an industrial serial protocol state detection algorithm based on discrete time Mar-kov chain (DTMC) is proposed.This method utilizes the characteristics of limited behavior and state of the industrial control system (ICS),and automatically constructs the normal behavior model of ICS&boxh;&boxh;DTMC,based on the historical traffic data of the serial link protocol.The model contains behavior information such as state event,state transition,state transition probability and state transition time interval.Then the behavior information contained in the model is used as the state detection rule set.When the state information generated in the detection phase is different from the state detection rule set information or the deviation exceeds the threshold,actions such as alarm or rejection are generated.At the same time,combined with the comprehensive packet inspection (CPI) technology,the detectable range of protocol payload data is increased.Finally,the experimental results show that the proposed algorithm can effectively detect semantic attacks and protect the security of serial links,the false positive rate is 5.3% and false negative rate is 0.6%.

Reactor core is the pivotal component of nuclear power system, and its integrity is an important prerequisite for safe operation of reactor. Traditional nuclear reactor core thermalhydraulic analysis methods cannot meet the high precision simulation requirements of advanced nuclear power systems in the future. In this paper, based on open source CFD platform OpenFOAM, a coolant flow heat transfer model considering diffusion due to turbulent mixing between adjacent coolant channels and rod bundle structure characteristics of pressurized water reactor (PWR) was established. A fuel rod heat conduction model was built to describe the internal temperature distribution formed by multiple nodes placed along the radial direction of fuel rods, and a coupled heat transfer model were proposed according to the mapping relationship between the external boundary condition of fuel rod heat conduction equation and convective heat transfer energy source term in coolant governing equation. The threedimensional subchannel thermal-hydraulic characteristics analysis code CorTAF for PWR core based on finite volume method was developed. After that, various fuel assembly flow and heat transfer experiments were selected to carry out model validation. For GE3×3 experiment, the calculated results of coolant velocity distribution in each channel of test section agree well with the experimental data, indicating that the CorTAF code can predict the flow characteristics in the fuel assembly effectively against COBRA code with similar computational accuracy. For Weiss experiment, the calculated results of coolant flow rate distribution in each assembly of test section are in good agreement with the experimental data, which illustrates that the CorTAF code can accurately predict the flow characteristics in parallel open assemblies under inlet partially blocked condition. For PNL2×6 experiment, the calculated results of coolant temperature and velocity distribution along center line of experimental section are basically consistent with the experimental data and those calculated by CUPID and MATRA codes, demonstrating that the CorTAF code can obtain the flow and heat transfer characteristics in the rod bundle assembly under condition of transverse nonuniform heating, and the error may be caused by the difference of data acquisition methods. In conclusion, the CorTAF code is proved to be suitable for predicting the flow and heat transfer characteristics in the rod bundle fuel assembly. The work in this paper has reference significance for the development of core safety analysis tools for PWR. Subsequently, further model optimization and thermalhydraulic characteristics analysis of the full PWR core under both steadystate operation and transient accident conditions will be carried out, and research on neutronics and thermalhydraulics coupling will be performed based on OpenFOAM.

In the internet of vehicles systems that combining mobile edge computing (MEC) with non-orthogonal multiple access (NOMA) technology,to solve the high latency problem when user processes computationally intensive and latency-sensitive task,a strategy of task offloading,migration and cache optimization based on game theory and Q learning is proposed.Firstly,the mo-del of offloading delay,migration delay and cache delay of the internet of vehicles task based on NOMA-MEC is established.Se-condly,we use the cooperative game method to obtain the optimal user group to optimize the offloading delay.Finally,in order to avoid local optima,the Q learning algorithm is utilized to optimize the joint delay of the migration cache in the user group.The simulation results show that compared with other solutions,the proposed algorithm can effectively improve the offloading efficiency and reduce the task delay by about 22% to 43%.

In order to solve the poor quality problem of domain embedding space caused by inadequate military corpus which makes low accuracy of applying deep neural network model to military named entity recognition,this paper introduces a domain adaptive method to help learn the embedding of military fields from more useful information of additional fields through distributed representation of words.First,we establish the domain dictionary and combine CRF algorithm to perform domain adaptive word segment with the collected general domain and military areas corpus as training corpus for embedding,and word vectors are used as features and spliced with character vectors to enrich the embedding information and to validate the effect of word segmentation.Then the domain adaptive transformation is carried out to the heterogeneous embedded space of the general domain and the military domain,and the domain adaptive embedding is generated,as the input to BiLSTM-CRF layer of base model.At last,the recognition evaluation is carried out through CoNLL-2000.The experimental results show that,under the same model,the recognition precision rate (P),recall rate (R),and integrated F1 value (F1) of the proposed method are improved by 2.17%,1.04%,and 1.59%,respectively,compared with the military field embedding trained by a corpus which is obtained from general word segmentation.

At present, the relevant regulatory bodies overseeing railway and urban rail transit infrastructure monitoring universally mandate the utilization of automated monitoring techniques and real-time transmission of monitoring data to network platforms. The conventional manual geodetic leveling method is excessively time-consuming and labor-intensive, failing to meet contemporary industry standards. To rectify the issue of automated total station vertical displacement monitoring accuracy not meeting manual geodetic leveling precision, an indirect elevation measurement approach grounded in fundamental principles was implemented to alleviate earth curvature and atmospheric refraction effects on vertical displacement monitoring. Initially, the design of the automated monitoring route was based on the principle of "adjacent points with similar observation distances". Subsequent preprocessing of zenith distance and distance measurements ensured compliance with field observation data limits, thereby ensuring original observation data accuracy. Finally, a leveling route adjustment computed elevation values for each monitored point. Exemplary analysis demonstrates that under specific conditions the method fulfills second-class leveling accuracy requirements. [ABSTRACT FROM AUTHOR]

Helical coil steam generator has the advantages of compact structure, high heat transfer efficiency, strong resistance to thermal expansion stress, and has been widely applied in energy and power engineering, chemical industry and other fields. As the energy transfer facility between firstsecond loops and the isolation barrier for radioactive working medium, the inner structure of helical coil steam generator is extremely complicated, hence its structural integrity and operation reliability are necessary guarantee for the nuclear power plant safety. In this paper, the porous media method was adopted to simplify the complex structure of the multilayer helical coil domain in heat exchange assemblies, a shell side working fluid flow heat transfer characteristics analysis model was established, and the tube side watersteam two phase flow boiling heat transfer characteristics analysis model was established based on the homogeneous flow hypothesis. The gridnode data mapping method was applied to realize the coupled heat transfer simulation between shell side and tube side, and a three-dimensional full-scale thermalhydraulic characteristics analysis code HeTAF for the helical coil steam generator was developed based on the open source CFD platform OpenFOAM. The validation was performed against flow boiling heat transfer experiment of helical tube by Santini, and the calculation results of heat transfer coefficient variation with quantity are in good agreement with the measured data, indicating that the adopted model package are capable for accurate prediction under high mass flux rate and heat flux experimental condition. The helical coil oncethrough steam generator in high temperature gas cooled reactorpebble module was selected as the research object. The simulation of single heat transfer assembly under full power operating condition was performed using HeTAF. The distributions of thermalhydraulic parameters including tube side and shell side fluid temperatures, heat transfer coefficient, heat transfer power, void fraction and equilibrium quantity along tube length were obtained, and the transition process of each phase state and dominant heat transfer mechanism in the helical tube was predicted. The calculation results of helium and steam outlet temperature are fixed well with the design value with absolute errors of 5.29 K and 5.76 K respectively, which illustrates that the HeTAF can effectively predict the thermalhydraulic characteristics of both shell side and tube side of single heat transfer assembly. The work in this paper has significance reference for the design and safety analysis of helical coil steam generator. In the future, based on the existing methodology and simulation strategy, the fullscale coupled thermalhydraulic characteristics analysis of the helical coil steam generator will be conducted, and supplementary validation and subsequent optimization of HeTAF code will be carried out continuously.

Objective To explore the association of cardiac disease associated genetic variants and the high incidence of Yunnan sudden unexplained death （YNSUD） in Yi nationality. Methods The genomic DNA was extracted from peripheral blood samples collected from 205 Yi villagers from YNSUD aggregative villages （inpatient group） and 197 healthy Yi villagers from neighboring villages （control group）. Fifty-two single nucleotide variants （SNVs） of 25 cardiac disease associated genes were genotyped using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. The SPSS 17.0 was used to analyze data. The pathogenicities of variants with differences between the two groups that have statistical significance were predicted by protein function prediction software PolyPhen-2 and SIFT. All villagers from inpatient group were given electrocardiogram （ECG） examination using a 12-lead electrocardiograph. Results The allele frequency and the genotype frequency of missense mutation DSG2 （rs2278792, c.2318G>A, p.R773K） of pathogenic genes of arrhythmogenic right ventricular cardiomyopathy （ARVC） in inpatient group was higher than that in control group （P

Aiming at the current rock burst problems encountered in hard rock excavation construction，a set of six-degree-of-freedom automatic excavation equipment which can replace the current artificial slag and can work well in a narrow working space is designed.The specific design is on the basis of the traditional excavating machine，two telescopic arm structures and a swing arm structure are added，and each rod length and each joint variable are set by kinematically modeling the mechanical arm.The design overcomes the problem of the small amount of operable space and the protection of the supporting I-beam for the pre-supported tunnel，and expands the working space of the conventional excavation equipment in a narrow space.The overall structure of the excavation equipment and the kinematics modeling process are expounded.By using the characteristics of Monte Carlo method in random number application，the workspace of this device is simulated.At the same time，the joint parameters are reversed and verified.The results are in line with the expected joint operating range.The slag cleaning device can improve the working efficiency of cleaning the gravel caused by rock burst，and can reduce the construction cost of the hard rock tunneling.

The virtual factory model of manufacturing industry can reduce cost and increase efficiency, optimize service quality, so it is good choice to cope with the fierce global competition. In order to continuously improve product quality in the mode, the accuracy enhancement of CNC equipment related to the production process was mainly focused on, which were the key techniques of error compensation, including error source analysis, error modeling, error measurement and error data processing. Therefore, the five-axis machine tool was taken as the representative of CNC equipment, and 45 geometric errors which affected its accuracy were found out; through error modeling, the relationship between these 45 errors and the total system error of the five-axis machine tool was established; then, according to the error characteristics of the five-axis machine tool, the measuring system was constructed and its effectiveness was verified; finally, data handling was carried out for the measurement data, which provided non-measurement node data and greatly reduced the amount of data information, so it laid a data foundation for rapid and effective error compensation. [ABSTRACT FROM AUTHOR]

The extraction and separation of ferrum and copper from waste ternary cathode material by Cyanex 302 (the main component is di(2,4,4-trimethylamyl) monothiophosphoric acid) was studied. The effects of H+ concentration, extractor concentration and temperature on the extraction and separation performance of Cyanex 302 were investigated. And the technological conditions for the stripping of ferrum and copper in supported organic phase were determined. The process flow of extracting ferrum and copper from waste ternary cathode material leaching solution is designed. The results show that the optimal extraction conditions are 0. 1 mol/L Cyanex 302 concentration, 0. 1 mol/L H+ concentration, room temperature. Under these conditions, the extraction rates of ferrum and copper are over 99. 9 %, while the extraction rates of Ni (II), Co (II), Mn (II), and Li (II) are all below 0. 003%. The optimal stripping agent for ferrum is 1 mol/L H2SO4 and that for copper is 1. 5 mol/L HNO3. The process can effectively separate copper and ferrum from the leaching solution. [ABSTRACT FROM AUTHOR]

In order to quantitatively characterize the ability of PVD(physical vapor deposition) film sensors to detect cracks in metallic structures, the process parameters applied to LY12-CZ aluminium alloys were first optimized using orthogonal tests, and coin shape, 1mm concentric dual ring shape, 0.5mm concentric tricyclic shape PVD film sensors were prepared on three groups of specimen with central hole using these parameters. Subsequently, the on-line monitoring experiment of fatigue cracks was carried out under laboratory conditions, the potential output signals of the PVD film sensors and microscope observations were compared and analysed. Finally, the probability of detection curves of all kinds of PVD thin-film sensors and PVD film sensor in different shapes were plotted separately using the improved crack size separation method and binomial distribution detection model. PVD thin-film sensors have 93.56% detection probability for cracks with length greater than 0.99mm at 95% confidence level. Compared to coin-shaped thin-film sensors, concentric ring shape film sensors are more sensitive to cracks smaller than 0.5mm, and the sensors with finer channel width have the higher probability of detection on small size cracks.

Due to the complicated structure of the loop-type compound epicyclic gear system, the torque and power relationship between the basic components in the system is complex and variable, forming a variety of power flow types. In order to quickly judge the power flow type of the system during the design process, a composite lever analysis method is proposed. Based on the lever model of a single epicyclic gear train, combined with the structural characteristics of the coupled system, used the superposition principle, a composite lever model reflecting the characteristics of the loop system is established. Then the application method of this model during analyze the characteristics of single loop system is introduced. This composite lever model is found to intuitively reflect the speed, torque and power relationship among the basic components, and then derive the power flow type of the single loop system. The values of the above characteristics can also be calculated by the force arms of the model that reflect the characteristic parameters of the epicyclic gear systems. On this basis, the application of this method in the power flow analysis of dual-loop system is introduced, which provides a new idea for the analysis of multi-loop system.

A novel parallel hybrid powertrain was proposed. The PX type single-loop system was adopted. It could effectively avoid the CVT’s torque and power capacity. By serially connection to 2-speed gearbox,The PX type single-loop system ratio spread was enlarged. For regenerative braking mode,the power flow reversibility of the PX single loop system was verified.The electric motor was used to realize pure electric drive and recovery braking energy. At high speed and heavy load,the vehicle was driven simultaneously by the engine and the motor. The bond graph model of the powertrain was established,and the state equation of the system was given. Based on MATLAB/Simulink,the vehicle simulation model was established,and the highway portion of the US06 drive cycle was selected to simulate the powertrain. The simulation results show that: through mode switch,engine operates in high efficiency areas,and the actual speed of the vehicle can well follow the driving cycle. At the same time,the battery state of charge is ensured in the expected range before and after the simulation.

[Objectives] In order to detect the weak stray magnetic field signal of the induction machine during operation, this paper presents an optimized design method of low noise Induction Magnetometer (IM).[Methods] By analyzing the frequency response and noise model of the IM,the main noise sources that affect the performance of the IM at different frequency bands are proposed,and the formula of the equivalent input magnetic field noise level is obtained. Based on this,a special low-noise amplifier circuit is designed. And the optimal design method of the IM is proposed. Besides,for different restrictions,the optimization formulas and results are given. In addition,a small IM with a linear response to 10 kHz is fabricated,and the magnetic field of an induction machine under normal and fault condition is tested.[Results] The test results show that the equivalent magnetic field noise level is 2 pT/√Hz at 10 Hz,and 0.7 fT/√Hz at 20 kHz.[Conclusions] Through optimized design,the IM can effectively monitor the magnetic field change of the induction machine,and can be used for online monitoring.

In order to investigate the moisture property of carbon fiber reinforced resin composite stiffened panel in hygrothermal environment, moisture experiments were conducted in condition of 70℃/85%RH. Stage moisture model was proposed and moisture behaviors were analyzed by finite element method. The results show that the moisture curve of experimental result agrees with Fick's diffusion law perfectly in initial moisture stage. However, stage moisture behavior exists in later moisture period. The moisture curve of stage moisture model agrees with finite element result,with an error less than 5% compared with the experimental result. The composite stiffened panel moisture mechanism is revealed by moisture concentration distribution. Additionally, the saturated moisture rate in different thickness zones is not synchronous, which is main reason resulting in stage moisture.

K4536 alloy formed by SLM was treated by HIP, and the effects of HIP on the microstructure and high-temperature mechanical properties were studied. The results show that the surface of sample manufactured by SLM has cracks, and the longitudinal and horizontal microstructures are different. After HIP processing, the cracks in the sample is repaired to some extent, the microstructure of the sample also is changed, and many second phase particles are dissolved out from the matrix. We know that the precipitation is M23C6 phase by TEM diffraction analysis. Furthermore, the surface of sample has “white bright layer” with the thickness of about 30 μm, the “white bright layer” is resulted by the decrease of Cr by EDS energy spectrum analysis. The K4536 alloy sample formed by SLM has different high-temperature tensile properties in the vertical and horizontal, and the vertical performance is better than that of horizontal. After HIP processing, the vertical and horizontal performances have little difference, and the high-temperature strength of the sample is reduced, the high-temperature plasticity is increased.

The consumption of coal is very complex, and the forecast and analysis of coal consumption can provide reference for rational arrangement of coal production.The usual prediction is based on the ARMA or ARIMA model, which neither consider its long-term memory nor consider the non-Gaussian noise.In this paper, fractional-order signal processing and long-term memory processes are introduced and the use of fractional-order differential ARIMA model is proposed to model and predict the coal consumption.The experimental results show that the generalization of ARFIMA model can predict the trend of change and the deviations are smaller and closer to the actual value, which provides a reference for the future production and consumption decision.

Based on the test data of top soil, Chinese medicinal materials and root soil samples, the paper studies the contents, spatial distribution characteristics and pollution degrees of five heavy metal elements including As, Cd, Cu, Hg and Pb in the topsoil of Chinese medicinal materials planting area of Niujiayingzi Town in Xibo River Basin, Chifeng City, Inner Mongolia, as well as the accumulation characteristics of soil heavy metals by different Chinese medicinal materials and heavy metal pollution degree of herbs. The results show that the five elements in the topsoil of Chinese medicinal materials planting area share the same origin, mainly from the parent material, and in association, with the mean contents of 8.729x10-6, 0.142x10-6, 21.146x10-6, 0.036x10-6 and 23.651 x 10-6, respectively. The variation coefficients of Hg and Cd are 0.639 and 0.472 respectively, reaching the intensity variation, for their low soil background contents and more susceptible to various factors. Both the single and comprehensive pollution indexes of the soil heavy metals are less than 0.7, which shows a clean level of soil quality and meets the soil environmental requirements for the GAP base construction of Chinese medicinal materials. The concentration coefficients or pollution indexes of heavy metals in the medicinal parts of platycodon grandiflorum, glehnia littoralis and achyranthes bidentata are all less than 0.50, with their contents much lower than the limit value of heavy metals in Chinese medicinal materials. The Chinese medicinal materials produced in the planting area of Niujiyingzi Town all meet the requirements of green standard. [ABSTRACT FROM AUTHOR]

Wading projects are likely to bring about changes of the original hydrodynamic conditions of the river, and this may further affect the flood discharge capacity of the river course. Thus, it is of great significance to study the flood risk of the river course with or without the wading projects, so that we can well maintain the project, regulate river course and ensure regional flood control security. Based on the random simulation of four uncertain factors, namely peak flood discharge, initial water level, river course roughness and dike elevation, this paper analyzed the stress of aqueduct under flood action, and then calculated the water surface line of the river. Combined with theforce conditions and water surface line calculation results, the conventional Monte Carlo method and the Monte Carlo method based on Latin hypercube sampling were both used to calculate the flood risk of river course with or without an aqueduct. The results show that: 1 When the water level in Gangqian Aqueduct is 0.5, 1.0, 1.5 and 2.0 m, the flood discharge capacity of Qingfeng Mountain stream, compared with its designed discharge of 1 200 m³/s, respectively decreases by 36.68%, 27.87%, 19.00% and 10.05%. 2 In the case of having no aqueduct in its river course, the flood risk of Qingfeng Mountain stream course is 0.007. In the case of having Gangqian Aqueduct in its river course, when the water level in the aqueduct was 0.5, 1.0, 1.5 and 2.0 m respectively, the flood risk of Qingfeng Mountain stream course is 0.34, 0.045, 0.016, 0.012 in turn. 3 Keep the water level in Gangqian Aqueduct at the highest value within the safe range. When the discharge of Qingfeng Mountain stream exceeds 1 600 m³/s, the flood risk of its river course still rises significantly with the increase in the flood flow. Therefore, in this case, Gangqian Aqueduct would have to be scrapped to ensure the flood discharge capacity of Qingfeng Mountain stream. 4 Both the conventional Monte Carlo method and the Monte Carlo method based on Latin Hypercube Sampling are suitable for assessing the influence of aqueduct on flood risk of river course, and the latter has better convergence. In summary, building adueducts in river courses would have a negative impact on the river courses' flood discharge capacity. It results in the flood discharge capacity of the river course being lower than the designed discharge, and further, led to the flood risk of river course increasing. To a certain extent, raising water level in the aqueduct can reduce the flood risk of river course. [ABSTRACT FROM AUTHOR]

Based on bond graph theory,considering the time-varying meshing stiffness,damping and tooth surface friction force of internal and external gear,using LuGre friction model,the bond graph model of NGW type planetary gear was established. And then,the bond graph analysis models of the XP type and PX type single loop planetary transmission system were set up. The speed and efficiency of XP type and PX type single loop planetary transmission system was computed and simulated in 20 sim software. The results show that the modeling theory and method of bond graph can be used to solve the nonlinear dynamic problems of single loop planetary transmission system.

According to the characteristics of shoulder joint,a decoupling parallel bionic shoulder joint driven by pneumatic muscle actuators（ PMAs） is presented. Based on screw theory,the freedoms of 3-DOF parallel mechanism are analyzed. The kinematics model of parallel mechanism is established because of its simple reverse solution. Besides,its dynamics model is also established based on Lagrange method. In simulation control,computed torque method can better control motion of parallel mechanism,which verifies the correctness of the dynamic model at the same time.

Aiming at the research of pure electric power transmission,the single low-power motor has the problems of low power,small speed range which can cause motor damage and the single high-power motor has the problem of large own load,large energy loss and other issues. A differential type parallel coupled input single output power transmission test bench is designed,the relationship between input and output speed and power loss when the load changed under different working modes is studied. The results of simulation test and the test bench test run shows,when the motor reaches steady state operation,the rated power is 0. 49 k W,the average output power is about 0. 482 k W,power loss is less than 10 W,speed range increases 29. 17%,transmission efficiency is greater than 81. 7%,output power is enhanced effectively and also has fine repeatability. The experimental research platform is provided for the further research on the dynamic optimization of the coupling transmission system.

To solve the problem of the contact ellipse in the geometric contact simulation of gear teeth which needs the numerical approximation of the quadratic approximation of the tooth surface and the complicated curvature derivation,the method of contact ellipse calculation based on numerical iteration is proposed. Firstly,the instantaneous contact point is solved by meshing basic equations,then the whole week search is conducted according to the given elastic deformation starting from the point,the instantaneous contact ellipse and the long and short axes of the contact position are obtained,and then the whole tooth surface contact prints are got.Finally,taking a pair of cycloidal gear hypoid gears as an example,the feasibility of this method is verified by comparison with commercial software and rolling inspection results.