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The multi-seam occurrence conditions in the western mining area have brought forth prominent and common issues such as "contradictions in mining face layout, variable overburden structure, and superimposed surface migration". Exploring the coordinated green mining technology suitable for high-intensity mining of multiple coal seams is the key to the safe and efficient mining of multiple coal seams in the western mining area. In response to the main technical challenges faced in the high-intensity mining of shallow-buried thick coal seam groups, several key technologies for the coordinated green mining of shallow-buried multi-seam groups have been systematically expounded from aspects such as the spatio-temporal layout of multi-seam mining, the stability control of the rock strata in the working face, and the surface subsidence under repeated disturbances. The following research results have been obtained: ① The interlayer interaction mechanism of high-intensity mining of multiple coal seams in the western region has been revealed. A quantitative criterion and evaluation method for repeated mining disturbances of multiple coal seams have been constructed. An innovative coordinated mining technology with the staggered distribution of “thin, medium, and thick” coal seams aiming at minimizing inter layer disturbances has been proposed. ② The stability control technology of the rock strata in the multi-seam working face has been put forward. The full overburden structure failure model has been established, and the interaction law between the support and the surrounding rock under the condition of full overburden structure failure has been revealed. On this basis, in response to the demand of using different support strategies at different positions of the multi-seam mining working face, an anti-impact double telescopic column for the working face support and a monitoring system for the support state of the advanced roadway have been developed to achieve safe, efficient and stable support in multiple areas of the working face. ③ By revealing the dynamic movement characteristics of the surface and the development law of surface fractures under the oblique superimposed mining of shallow-buried multi-seam coal seams, the determination method of the surface subsidence coefficient has been given. The key treatment technology combining "soil reconstruction – in-situ filling – micro-topography modification" for fractures in the subsidence area has been developed, effectively preventing the surface subsidence of coal mining in the loess gully area. The above core technologies have been successfully applied in more than 20 large-scale coal mines such as Zhangjiamao, Ningtiaota, and Hongliulin, providing technical support for the high-quality and sustainable development of the western mining area in China.

In order to study the effect of liquid nitrogen injection cooling on spontaneous combustion of coal, coal samples from the second and third panel areas of Tingnan Coal Mine were selected for thermal and physical property experiments. First, the coal sample was pretreated by LFA457 laser flash analyzer, and then the thermophysical property parameters of the coal sample were measured in the range of 30-300 ℃, and the change law of the thermophysical property parameters of the coal sample with temperature was obtained after liquid nitrogen injection and cooling, and the factors affecting the thermophysical properties of the coal sample were compared and analyzed. The results show that the thermal diffusivity decreases with the increase of temperature, and the specific heat capacity and thermal conductivity increase with the increase of temperature; in the range of 30-200 ℃, the average change rate of thermal property parameters of coal samples after liquid nitrogen injection treatment is higher than that of raw coal samples, indicating that liquid nitrogen injection treatment will increase the sensitivity of coal samples to temperature; in addition, at the same temperature, the thermal physical property parameters of coal samples after liquid nitrogen injection treatment increased to different degrees compared with the original coal samples, and the average growth rate of thermal diffusion coefficient was the highest, indicating that the thermal diffusion ability of coal samples after liquid nitrogen injection treatment was enhanced during the oxidation and heating process.

Landslide are one of the most common types of geological disasters in China, posing a serious threat to the safety of people's lives and properties due to their propensity and frequency. The stability assessment of landslides is crucial in landslide disaster prevention and mitigation works. Considering the fuzzy nature of landslide inducing factors, a certain accumulation layer landslide in Xinpu Town, Mianxian County is taken as an example in this article. Based on the analysis of geological environmental conditions, a fuzzy mathematical method is employed for landslide stability assessment. The concept of "entropy" from thermodynamics is introduced, and the entropy weight method is used to determine the weights of landslide inducing factors. Consequently, a new method for landslide stability assessment based on the improved entropy weighting method in fuzzy mathematics is proposed. The results show that the proposed method overcomes the subjectivity in determining the weights of landslide influencing factors in traditional fuzzy comprehensive evaluation methods. Validation through quantitative analysis of landslide stability using numerical simulation method found that the evaluation conclusions of the two methods were in good consistent, indicating the reliability of the proposed new method. The improved fuzzy mathematical landslide stability assessment based on entropy weighting method is relatively fast and simple, making it suitable for landslide disaster prevention and mitigation works in emergency situations such as rapid disaster warning of impending disasters and emergency rescue.

Aeroelastic divergence analysis of a stable wing structure was performed using a coupled aerodynamic/structural method and validated using wind tunnel tests. To ensure the accuracy of numerical analysis, CFD method was used for aerodynamic force calculation and finite element method was used for structural deformation calculation. The wind tunnel test used a sidewall insertion mechanism for support and measured the static aeroelastic divergence characteristics through strain measurement and high-speed photography. The stable wing model was used as the research object for studying the static aeroelastic divergence characteristics in supersonic state. The results of numerical calculation and wind tunnel test showed that the CFD/CSD coupling method can accurately predict the static aeroelastic divergence boundary. Static aeroelastic divergence presents an explosive form of destruction. The static aeroelastic unstable structure first suffers from elastic loading exceeding the structural strength limit and the damage occurs with the dynamic pressure not reaching the divergence boundary. Accurate prediction of the static aeroelastic divergence boundary of the aircraft is necessary for aircraft structural design.

Urban underground space resource is one of the vital resources of the city. Shenzhen is the city with limited land resources and urgently needs to carry out geological suitability evaluation of underground space to guide the development and utilization of underground space. However, the development of underground space resource is restricted by a variety of geological factors. It is necessary to use appropriate methods to evaluate the geological suitability of underground space development. Taking the Nanshan District of Shenzhen as the study area, this paper proposes a constraint evaluation system that takes the constrained geological factors as the first-level evaluation index and combines the geological background of the study area with the planning of underground space resources utilization in Shenzhen. The geological suitability of shallow underground space (0−15 m) and sub-shallow underground space (>15−30 m) in the study area of the conventional system and constrained system is evaluated by using the empirical score evaluation method and fuzzy comprehensive evaluation method. The results show that (1) compared with the conventional evaluation system, the constraint evaluation system improves the overall weight of the constraint geological factors. (2) According to the evaluation results of the constraint system, the poor and unsuitable areas are mainly distributed in the fault zone, high incidence of geological disasters and surface water area, which is more consistent with the actual geological conditions of the study area. (3) Attention should be paid to the geological problems such as stratum instability and ground collapse caused by sand liquefaction in the unsuitable areas during the development and utilization of the key development zones in planning. Meanwhile, geological problems such as rock fragmentation and groundwater enrichment in the region of restricted active faults should be avoided reasonably. This study strongly supports the planning of underground space resource utilization in the Nanshan District of Shenzhen.

In order to solve the key security problem in attribute-based encryption, a ciphertext policy attribute-based encryption scheme against key abuse was proposed based on the ring learning with error over ring and the access structure of ordered binary decision diagram.Firstly, two different institutions were constructed to jointly generate the user’s secret key, which reduced the risk of key disclosure by institutions.Secondly, the user’s specific information was embedded in each secret key to realize the traceability of the key, and the access of illegal users and malicious users were avoided by maintaining the white list.In addition, the access structure of ordered binary decision diagram was adopted by the proposed scheme, and the positive and negative values of attributes on the basis of supporting attribute AND, OR and Threshold operation were increased.Analysis shows that the proposed scheme meets the distinguishable security of anti-collusion attack and chosen-plaintext attack, reduces the storage and computing overhead, and it is more practical than other schemes.

The applicability of first-generation of Chinese land surface reanalysis dataset （CRA40/Land） has been evaluated with the observations from 2231 national meteorological stations and further compared with the ERA5 and CFSR datasets in terms of the spatial and temporal variations of monthly air temperature and precipitation.Triangulation linear interpolation is used to interpolate grid data into stations， and station data into grid.The China mainland is divided into four regions according to the stations distribution and topographic features.The bias， standard deviation ratio， root mean square error （RMSE）， correlation coefficient and model skill of the 3 reanalysis datasets in four regions are computed to compare the accuracy and evaluate the application.The comparative results suggest that the CRA40， ERA5 and CFSR datasets can reproduce similar spatio-temporal distribution patterns of the monthly air temperature and precipitation with the observations in Mainland of China.In particular， they all show much better performance in the eastern China than in western China and in winter than in summer.For the monthly air temperature， the mean errors of the 3 reanalysis datasets are generally within 2 ℃， with slightly better performance for the CRA40 and ERA5 datasets.For the monthly precipitation， the errors of the 3 reanalysis datasets show large differences， the CRA40 performs the best and shows the highest applicability over Mainland of China among the 3 datasets.

Loess slopes are often prone to creeping after being subjected to rainfall, artificial irrigation, river water infiltration, etc. Eventually a landslide occurred, even causing a catastrophic accident. There are few studies on the creep properties of loess landslide soil under different water content in the existing literature, and there is a lack of quantitative analysis of the law. A series of triaxial creep tests of sliding zone soil of loess landslide in the Secaowan Village, Yulin City have been carried. The stress-strain-time curves and isochronous stress-strain curves with different water contents (w=10%，12%，14%，16%，18%, w represents the water content) are obtained and the influence of water content on the creep characteristics of loess is analyzed as well. The long-term strength of loess is obtained by using the isochronous curve method. The research results show that (1) When the water content of the sample is larger, the deviator stress required for the creep failure of the sample is smaller, and the axial strain is larger. This phenomenon can be explained by the electric double layer theory as follows: The thickness of free water increases, the degree of cementation among soil particles decreases, and the water film will lubricate the soil particles and make them easy to slip. (2) When the water content of the sample is larger, the time required for the creep strain to reach a stable state after each level of load is applied is longer. This phenomenon can be explained as follows: The increase of loess moisture reduces the structural integrity of the soil, and the adjustment of the internal structure of the soil is relatively slow under the action of stress. Therefore, it takes a longer time for the pore water pressure to dissipate during consolidation and creep. (3) By analyzing the surface morphology of the creep failure of the loess sample, it is found that when the water content is small, the sample after the creep failure has an obvious shear failure surface. When the water content of the sample is larger, the lateral swelling is more likely to occur, showing the characteristics of plastic failure, and indicating that when the moisture content is larger, the softening effect of water is greater than the effect of water on the crack expansion of the soil. (4) The long-term strength loss rate of loess is introduced. It reveals the law of long-term strength and long-term strength loss rate of loess landslide soil under different water content. The research results can provide a reference for the long-term stability analysis of loess landslides.

Mastering the spatial distribution of near-surface air temperature is essential for the scientific understanding of ecological environment changes and land-atmospheric thermodynamic interaction mechanisms.However， the uneven distribution of meteorological stations poses a challenge for regional air temperature interpolation.Based on the monthly mean temperature of 711 meteorological stations in China， this paper analyzed the correlation between the monthly mean temperature with latitude， longitude， and elevation.We used three machine learning methods： random forest （RF）， support vector machine （SVM）， and Gaussian process regression （GPR） to spatially interpolated the air temperature in China.Then the interpolation results of the machine learning were compared with traditional interpolation methods including inverse distance weighting （IDW）， ordinary Kriging （OK）， and ANUSPLIN， as well as existing Global Land Data Assimilation System air temperature data products （GLDAS）.Results showed that： （1） The accuracy of temperature interpolation using machine learning is higher than that of traditional methods IDW and OK in China， and the interpolation accuracy of summer temperature is significantly improved.（2） Among the three machine learning methods， GPR performed the best， followed by SVM and RF.ANUSPLIN has fairly high interpolation accuracy， but lower than GPR.（3） In the Qinghai-Xiznag Plateau （QXP） where meteorological stations are sparse and unevenly distributed， the three machine learning methods have significantly higher interpolation accuracy than IDW and OK， even higher than ANUSPLIN.Especially in summer， the interpolation accuracy of machine learning in QXP is significantly improved.（4） Compared with the GLDAS air temperature data products， the temperature data obtained by the machine learning models have higher accuracy.The results in this paper indicate the effectiveness of the machine learning algorithm in temperature interpolation， which has positive significance for research in various fields related to temperature.

The Western Branch of the Tanlu fault in Bohai Sea refers to the Western Branch fault of Bohai segment of the Tanlu fault, the formation and evolution of which plays an important role in controlling the distribution of pre Cenozoic strata and the development of the structure of buried hills.Based on the data of 3D seismic, drilling and experimental data, the structural characteristics, genetic evolution model of the Western Branch of the Tanlu fault in Bohai Sea and its control on the formation of buried hills are analyzed.The results show that: ①the Western Branch of Tanlu fault in Bohai Sea is characterized by multi-stage superimposed activities in Indosinian, Yanshanian and Himalayan.The activation of late Himalayan is weak, and it is concealed under Cenozoic sediments.②The Western Branch of the Tanlu fault in Bohai Sea is divided into three segments: north, middle and south by nearly EW trending fault.There are some differences in the structural deformation patterns and strength of each segment in the key geological period.③The Western Branch of the Tanlu fault in Bohai Sea was originated from strike slip transition caused by uneven N-S compression in Indosinian.④Indosinian-Yanshanian strike slip thrust and associated folds in the Western Branch of the Tanlu fault in Bohai Sea are the key factors controlling the distribution of strata buried hills and the formation 19-6 buried hill structures of Bozhong.The research results can provide a basis for oil and gas exploration in Bohai Sea.

Considering the requirements of the space-integrated-ground information network, the technologies of on-board channelized switching and the technologies of on-board packet switching were surveyed.Among, the discussed channelized switching technologies include fl exible digital channelized switching and microwave photonic frequency conversion and switching, while the discussed packet switching technologies mainly include software-defi ned satellite network.Considering the future research directions of space networking and switching, the trends of on-board switching were discussed in terms of system capacity, reliability, effi ciency, and quality of service, which provided a reference for the long-term planning of the space-integrated-ground information network.

The conducted measurement campaigns at home and abroad were presented.Meanwhile, proposals and standard channel models from the international standardization organization were reviewed.The propagation characteristics of massive MIMO wireless channels were investigated based on the indoor and outdoor measurements.Moreover, the traditional and novel methods of channel modeling were analyzed.Finally, open research issues were presented.

Cableway piping is an effective construction method for the installation of steep mountain pipelines. Due to the obvious nonlinear process of cableway piping, the traditional numerical calculation cannot reasonably calculate the actual working conditions. Herein, the stress of the bearing cable and the cable support of the cableway hoisting system applied for reconstruction of China-Myanmar Pipeline was modeled, their stress and deformation were analyzed with the simulation optimization technique, and further a safe and economic cableway hoisting system was designed and installed, which successfully overcame the technical challenges for installation of the large-diameter mountainous pipelines and the long-distance steep pipelines. The results show that, the stress and displacement of the cableway hoisting system under the nonlinear stress state can be analyzed accurately with the simulation optimization technology. Compared with the calculation of traditional analytical method, the nonlinearity of cables could be fully considered, so that the actual working condition of cables can be simulated to the greatest extent and the change of full position force and displacement can be read in real time to ensure the service safety of cableway in construction of mountain pipelines, further providing reference for the future construction of mountain pipelines.

Based on physical property, casting thin section, scanning electron microscope, high-pressure mercury injection and other test analysis data, the fractal dimension of pore structure of tight sandstone reservoir was calculated by the method of mercury saturation and water saturation in the first Member of Lower Shihezi Formation in Hangjinqi area, and the relationship between fractal dimension and the physical properties of reservoir was analyzed.The results have shown that the average porosity and permeability of the Lower Shihezi Formation reservoir were 9.83% and 1.03×10-3 μm2, respectively.The reservoir space is mainly composed of intergranular dissolved pores, intragronular dissolved pores and residual intergranular pores.The overall fractal dimension calculated by the mercury saturation method is distributed in 2.138 4-2.829 2 with an average value of 2.396 5 while calculated by the water saturation method is distributed in 2.529 4-2.879 7 with an average value of 2.679 1.Compared with the water saturation method, the fractal dimension calculated by the mercury saturation method has a better correlation with the porosity, permeability and pore structure parameters, because the water saturation method tends to produce deviation on samples with smaller pore throat.The pore structure was divided into four types based on fractal dimension: Type Ⅰ(Df≤2.31), Type Ⅱ(2.31 < Df < 2.4), Type Ⅲ(2.4≤Df < 2.52), Ⅳ(Df≥2.52).Fractal dimension(Df), averoged radius of pore throct(Rm) and porosity(φ) were selected to calculate permeability by multiple nonlinear regression.The calculated permeability by multiple nonlinear regression shows strong correlation with measured permeability, whose correlation coefficient squared is more than 0.9, which means the permeability estimation model is suitable for the study area.

Given a vehicle image,vehicle re-identification aims to find the same vehicle caught by other cameras,it can be regarded as a sub-problem of image retrieval.In the real traffic surveillance system,vehicle re-identification can play a role in locating,supervising and criminal investigation of target vehicles.With the rise of deep neural networks and the release of large-scale dataset,improving the accuracy and efficiency of vehicle re-identification has become a research focus in the field of computer vision and multimedia in recent years.The vehicle re-identification methods from different perspectives were classified,and the overview,comparison and analysis in terms of feature extraction,design and performance were given in detail,and the challenges and future trends of vehicle re-identification were predicted.

Based on the lever method， the 2 planetary transmission schemes are sorted out， and the 2 planetary transmission schemes are analyzed. The 4 planetary hybrid transmission schemes are further synthesized according to the 2 planetary transmission schemes. On this basis， combined with the single switching principle， the arrangement of the 4 planetary rows joint elements is carried out. According to the plane graph decision theorem， combined with the 4 planetary row transmission scheme after the joint elements arrangement， the transmission scheme interference test is carried out， and finally the scheme of 4 planetary row transmission is obtained.

Visual tracking is one of the most important directions in computer vision.However,many state-of-the-art algorithms cannot track the interested object reliably due to occlusion during tracking process,which leads to deficiency of object information.In order to solve occlusion problem,a kernelized correlation tracking method based on point trajectories was proposed.Through analyzing long-term motion cues of the local information,point trajectories were labeled by spectral clustering.These labeled points were used to differentiate the foreground and background objects and thus detect whether the target was occluded or drifts.If drifting and occlusion occur,re-detection was used to detect the re-entering of the target.Experimental results show that the proposed algorithm can handle occlusion and drifting problems effectively.

During deep water oil well testing, the low temperature environment is easy to cause wax precipitation, which affects the normal operation of the test and increases operating costs and risks. Therefore, a numerical method for predicting the wax precipitation region in oil strings was proposed based on the temperature and pressure fields of deep water test string and the wax precipitation calculation model. And the factors affecting the wax precipitation region were analyzed. The results show that: the wax precipitation region decreases with the increase of production rate, and increases with the decrease of geothermal gradient, increase of water depth and drop of water-cut of produced fluid, and increases slightly with the increase of formation pressure. Due to the effect of temperature and pressure fields, wax precipitation region is large in test strings at the beginning of well production. Wax precipitation region gradually increases with the increase of shut-in time. These conclusions can guide wax prevention during the testing of deep water oil well, to ensure the success of the test. Key words: deep water oil and gas development, oil well testing, wellbore wax precipitation, temperature field, pressure field, wax precipitation region prediction

Real-time is an important criterion for evaluation of the real-time video traffic. Most of the existing scheduling algorithms have a wide distribution of user time delay. Firstly，based on the analysis of the existing scheduling algorithms and system rate，an algorithm called MT-LWDF was proposed. Secondly，obtained the range of β after the theoretical analysis，the optimal value of β was got by computer simulation. Then，β was set with the optimal value，the simulation relating to average delay of the system，maximum delay of the users，rate of the system，video frame loss rate and other performance was done. And the results indicate that MT-LWDF algorithm can reduce the distribution of user delay at the same time of optimizing the rate of the system.

Based on orthogonal matrices,a construction of zero-correlation zone (ZCZ) periodic complementary sequence sets are proposed.The resultant ZCZ periodic complementary sets have flexible number of subsequences.Moreover,the ZCZ periodic complementary sequence sets are optimal.ZCZ periodic complementary sequence sets with flexible subsequences are more useful in communication systems.

Energy consumption of wireless network is receiving more and more attention and has become one of key aspects of 5G while few researches on heterogeneous network （HetNet）load balancing focused in power consumption. User power model was built towards assignment model, based on which the augmented assign algorithm was proposed to minimize power of HetNet on condition of limited user data load. Simulation on system level platform show that power is effectively saved no matter base stations support sleep mode or not, meanwhile, ensure data rate of users.

This paper introduced the application range of the private cloud, discussed the characteristics of the self-developed and business and open source solutions, and analyzed the main advantage of the open source solution, then compared the mainstream projects of the open source cloud computing, such as Eucalyptus, OpenStack, OpenNebula and Nimbus, studied the structure of OpenStack mainly. Based on this, this paper presented the construction example of private cloud computing platform based on OpenStack, which major processes included configuration of base environment, components installation of Nova, Glance, Swift, Keystone and Horizon, deployment of virtual machines, and finally discussed the platform application examples in the cloud computing software testing.

A weighted cooperative spectrum sensing algorithm based on D-S evidence theory (DS-WCSS) was proposed.The algorithm took energy detector to perform local spectrum sensing,evaluated the credibility difference of cognit ve users according to the means and variances of test statistic in both hypotheses,set credibility weights based on the evaluation of credibility difference,and finally used D-S evidence theory to fuse data and made a decision.Simulation results show that the proposed algorithm has better performance than cooperative spectrum sensing algorithm based on D-S evidence theory and traditional hard-decisions.

Objective To analyze and compare the effects of transverse ligament injury on the stability and stress distribution of atlantoaxial complex fractures using 3D finite element method. Methods A male volunteer with a normal cervical spine was selected. The cranio-cervical region (C0-C3) was scanned using a 64-slice spiral CT scanner. Software such as Simpleware 3.0, Geomagic 12.0, and Hypermesh 12.0 were used to create a three-dimensional finite element model (FEM/Intact) of the C0-C3 segment. On the validated model, the anterior and posterior arches of C1 and the base of the odontoid process were fractured to create a composite fracture model (FEM/Fracture) simulating Jefferson/Type Ⅱ odontoid fracture. Two additional models were created: one with a ruptured transverse ligament of the atlas (FEM/RTL) and another with an intact transverse ligament (FEM/TL). The models were subjected to loading conditions of flexion, extension, lateral bending, and rotation, and the Von Mises stress distribution and vertebral segment motion were analyzed for each model under different loading conditions. Results The three-dimensional nonlinear finite element model of the atlantoaxial complex created in this study had a realistic appearance and good geometric similarity. The motion of each vertebral segment in the model was consistent with the results of Panjabi's in vitro experimental analysis. The composite fracture model of Jefferson/Type Ⅱ odontoid fracture with or without transverse ligament injury also had a realistic appearance and good geometric similarity. After combining the transverse ligament injury with the Jefferson/Type Ⅱ odontoid fracture, the instability of the upper cervical spine primarily concentrated at the atlantoaxial joint, with varying degrees of increased motion in flexion, extension, lateral bending, and axial rotation compared to the normal group. Conclusion Transverse ligament injury significantly affects the stability and stress distribution of atlantoaxial complex fractures. The finite element models established in this study can be used for biomechanical analysis of Jefferson/Type Ⅱ odontoid fracture combined with transverse ligament injury, and provide strong theoretical support for the selection of fixation methods in atlantoaxial complex fractures.

Metallic magnetic calorimetry holds significant promise in critical defense applications such as nuclear proliferation prevention, radionuclide classification, nuclear safety and anti-terrorism. Metallic magnetic calorimetry realizes energy resolution in the order of a few electron Volts by utilizing the significant contribution of heat capacity of a magnetic origin at milli-Kelvin temperatures in rare-earth doped Au films. For detecting gamma-ray photons with an energy of around 100 keV, the energy resolution is better than 0.1%, 10 times better than the high-purity germanium (HPGe) gamma spectrometer with the highest energy resolution. The metallic magnetic calorimeter can detect other radiation types than gamma rays such as alpha and beta emissions. Metallic magnetic calorimetry can also be used for precise measurement of astrophysical phenomena, cosmic rays and other high-energy physics phenomena. As an critical part of the metallic magnetic calorimeter, the pick-up coil plays a dual role in the sensor unit. It is not only responsible for converting magnetic flux changes into electrical signals, which is subsequently picked up by the SQUID chip, but also responsible for generating persistent excitation magnetic field and magnetizing the rare-earth doped sensor thin-film. The design configuration and electromagnetic parameters of pick-up coil can directly influence the energy resolution of the sensor. In the paper the influences of various parameters (e.g., number of turns of soil, duty ratio) on the electromagnetic characteristics using the finite element method was calculated. The actual pick-up coil size is in the order of micrometers. As direct measurement of such tiny devices is extremely difficult with conventional means and such measurements suffer high errors, in this paper scaled-up samples were measured, and the validity of the simulation model and parameters through comparison with measurement results was verified to provide a reliable foundation for design work of pick-up coils. The calculation results show that the influence of turn number of pick-up meander coil on inductance is more significant than other parameters such as duty ratio and loop pitch. With the increase of the duty ratio, the inductance shows a monotonic decrease trend. When the duty ratio increases from 30% to 70%, the inductance decreases by about 76.4%. On the other hand, with the increase of the turn number, the inductance shows an obvious increasing trend. When the turn number increases from 15 to 75, the inductance increases by about 253%. The simulation result also reveals the magnetic field distribution inside the metal magnetic calorimeter sensor pick-up coil, which provides critical information for the design of the sensor thin film.

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.

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.

Background Vitamin D levels decrease with age and are associated with the occurrence of osteoporosis, fractures, falls and muscle weakness that are common in older adults. In addition, its association with quality of life in the elderly has also been increasingly paid attention. Objective To investigate the vitamin D level and its correlation with health-related quality of life in the elderly population dwelling in community in Beijing, and to provide decision-making reference for improving the full life-cycle quality of life of this population. Methods The data of this study were obtained from the BEYOND research database carried out in Chaoyang District and Fengtai District of Beijing from November 2017 to July 2018. A total of 1 066 elderly people aged ≥ 60 were included for analysis. Clinical information including demographic and socioeconomic characteristics, biochemical markers of bone metabolism, bone mineral density, left and right hand grip strength, sitting test, and history of falls and fractures during 2-year follow-up was collected. According to the level of 25-hydroxyvitamin D〔25 (OH) D〕, the subjects were divided into vitamin D deficient group, vitamin D insufficient group and vitamin D sufficient group, and the EuroQol Five-dimensional Questionnaire (EQ-5D) was used to evaluate the quality of life of the subjects. Results Among the 1 066 subjects, 729 (68.39%) were in the vitamin D deficient group, 291 (27.30%) were in the vitamin D insufficient group, and 46 (4.32%) were in the vitamin D sufficient group. Serum levels of procollagen type 1 N-terminal propeptide (P1NP) , alkaline phosphatase (ALP) , parathyroid hormone (PTH) , osteocalcin (OST) , and cross-linked type I collagen carboxyl-terminal peptide (β-CTX) , left hip overall T value, right hip overall T value, and left hand grip strength were statistically significant among three groups (P

The attention neural process(ANP) model which adopts the method of generative model,takes any number context points of the sample as input,and outputs the distribution function of the entire sample,so as to approximate the function of Gaussian process regression(GPR) to realize the data fullfilling task.In reality,many scenes or datasets containe the attributes or labels data which are critical for generating the missing data.However,the ANP ignores full use of them.Inspired by CVAE model which control sample generation with lable as condition,this paper proposes global attribute attentional neural process(GANP),which embeds sample attributes or labels into ANP network to make the model generate samples more accurately,especially when the number of input context points are scarce.In detail,the sample attributes are embedded into the encoder network,so that the latent variables contain the sample attribute information.At the same time,the sample attributes are added as features in the decoder network to help generate more accurate samples.Finally,experimental results prove the superiority of GANP in both qualitative and quantitative,and it also reveals that GANP expands the application of NP families which can solve the Gaus-sian process regression problem more flexibly,quickly and accurately.

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.

As one of CFETR’s candidate blankets, water cooled ceramic breeder (WCCB) blanket undertakes important nuclear-related functions such as tritium breeding, nuclear heat extraction, and neutron shielding. The reliability of neutronics design directly affects the realization of CFETR tritium self-sustaining goal. In order to verify the reliability of the neutronics design tool, i.e. MCNP and FNEDL databases, in the WCCB blanket neutronics design, the WCCB scaling-down mock up was developed to carry out the neutronics experiment in the DT neutron environment, including two layers of lithium titanate, two layers of beryllium, three layers of cooling plate, and one layer of tungsten armor. The neutronics performance of the mock up are similar with the real blanket module. The mock up neutronics experiments were carried out using DT neutron generator, the simulated value (C) and experimental value (E) of neutronics parameters represented by tritium production rate (TPR) were analyzed. For TPR validation, two independent detection technologies were used, including the Li2TiO3 pellets as off-line TPR detectors, and the developed lithium glass detectors as on-line TPR detectors. The TPR validation was complemented by evaluating the predicted neutron-induced reaction rates of the Au, Zr foils. The experiments on the mock up were analyzed by MCNP-4C code and FENDL-3.0 nuclear data libraries, and the source term for Monte Carlo simulation was built using the custom-developed model based on depth profiling of tritium in the tritide target. The analysis results show that the C/E of TPR in the axis of two lithium titanate layers is 0.97 and 1.08 respectively, while there is a large deviation between the calculated and experimental values of TPR in the edge region of the mock up. According to the experimental results from Li2TiO3 pellets, the C/E of TPR at the edge of two lithium titanate layers is 0.65 and 0.82, respectively. The TPR is obviously underestimated by simulation at the edge of lithium titanate layers, confirmed by the C/E results of 197Au(n, γ)198Au reaction rate at the edge of lithium titanate layers, which are 0.72 and 0.90, respectively. It is indicated that there are unexpected scattered neutrons in the edge region of the mock up, resulting in the higher TPR than expected. The further experiments are needed to verify the influence of the scattered neutron on the TPR at the edge region of the mock up. To investigate the TPR gap between simulation and the experimental results from lithium glass detectors, the contribution of the fast neutrons on the 6Li(n, t)4He should be further studied. Also the other suggestions are provided for further experimental research, refering to the radiation protections and nuclear measurements.

Telomerase reverse transcriptase is a subunit of telomerase, which plays an important role in activating telomerase and regulating cell cycle. Human telomerase reverse transcriptase(hTERT) is mainly expressed in germ cells, embryonic stem cells and tumor cells, only a few expressed in normal cell. hTERT is mainly located in nucleus and also distributed in mitochondria. hTERT migration from nucleus into mitochondria is called the mitochondrial translocation of hTERT. Mitochondrial translocation of hTERT functions in the process of apoptosis, immortalization and drug resistance. Control of hTERT is a potential breakthrough in the treatment of diseases.

Chinese calligraphy is a thousand-year-old writing art. The question of how Chinese calligraphy artworks convey emotion has cast its spell over people for millennia. Calligraphers’ joys and sorrows were expressed in the complexity of the character strokes, style variations and general layouts. Determining how Chinese calligraphy aesthetic patterns emerged from the general layout of artworks is a challenging objective for researchers. Here we investigate the statistical fluctuation structure of Chinese calligraphy characters sizes using characters obtained from the calligraphy artwork “Preface to the Poems Collected from the Orchid Pavilion” which was praised as the best running script under heaven. We found that the character size distribution is a stretched exponential distribution. Moreover, the variations in the local correlation features in character size fluctuations can accurately reflect expressions of the calligrapher’s complex feelings. The fractal dimensions of character size fluctuations are close to the Fibonacci sequence. The Fibonacci number is first discovered in the Chinese calligraphy artworks, which inspires the aesthetics of Chinese calligraphy artworks and maybe also provides an approach to creating Chinese calligraphy artworks in multiple genres.

PURPOSE： To investigate the expression of tissue-active protein kinase C receptor 1 (RACK1) and epithelin glycoprotein 40 (EGP40) in oral squamous cell carcinoma (OSCC) and their relationship with clinicopathological features and prognosis., Methods: A total of 103 patients with OSCC who were admitted to Shangrao People's Hospital from January 2016 to February 2019 were prospectively selected as the research subjects. All patients underwent radical resection of OSCC and were followed up for 3 years. Immunohistochemistry was used to detect the positive expression levels of RACK1 and EGP40 in cancer tissues and adjacent tissues. The positive expression of RACK1 and EGP40 in cancer tissues and adjacent tissues were compared. The relationship between the positive expression level of RACK1 and EGP40 in cancer tissues of OSCC patients and clinicopathological parameters was analyzed. Factors affecting postoperative recurrence and metastasis in OSCC patients were analyzed. The relationship between the expression of RACK1 and EGP40 in cancer tissues and postoperative disease-free survival of OSCC patients was analyzed. SPSS 18.0 software package was used for statistical analysis of the data., Results: The positive expression rate of RACK1 and EGP40 in cancer tissues was significantly higher than those in adjacent tissues (P＜0.05). The positive expression rate of RACK1 and EGP40 in cancer tissues of OSCC patients with poorly differentiated, stage III, cervical lymph node metastasis, and infiltrating vessels was significantly higher than that in patients with moderate and high differentiation, stage II, no cervical lymph node metastasis, and no infiltrating vessels(P＜0.05). The positive expression rate of RACK1 in cancer tissue of OSCC patients in T3 stage was significantly higher than that in T2 stage(P＜0.05). Cox multivariate regression analysis showed pathological grade (RR=6.290, 95%CI: 2.588-15.287), cervical lymph node metastasis(RR=5.995, 95%CI: 2.467-14.571), RACK1 positive rate (RR=4.495, 95%CI: 1.850-10.925) and EGP40 positive rate (RR=4.559, 95%CI: 1.876-11.079) were factors affecting the recurrence and metastasis of OSCC patients after surgery(P＜0.05). The disease-free survival curve of patients with negative expression of RACK1 was significantly better than that of patients with positive expression (P＜0.05). The disease-free survival curve of patients with negative expression of EGP40 was significantly better than that of patients with positive expression (P＜0.05)., Conclusions: The expression of RACK1 and EGP40 in cancer tissues of OSCC patients is related to clinicopathological parameters and prognosis. Patients with positive expression of RACK1 and EGP40 have a high risk of recurrence and metastasis after surgery.

Purpose: To explore the appropriate surgical approach for each type of maxillary ameloblastoma., Methods: The clinical data of 92 patients with maxillary ameloblastoma were retrospectively analyzed. All patients were pathologically diagnosed, followed up for 3-8 years after surgery, maxillofacial CT and panoramic images were taken regularly to observe the surgical outcomes. SPSS 22.0 software package was used for data analysis., Results: The proportion of maxillary ameloblastoma in male and female patients was 3 to 1,with more male patients and the mean age was 45.77 years old. The total recurrence rate of 92 patients was 21.74%, among which unicystic ameloblastoma had no recurrence after different surgical procedures. Among 38 patients with typical maxillary ameloblastoma, 14 underwent curettage, 3 underwent decompression，16 underwent extended resection, 3 underwent subtotal maxillary resection, 1 underwent iliac bone transplantation after subtotal maxillary resection, and 1 underwent reconstruction with anterolateral thigh flap after subtotal maxillary resection. Among them, 18 had recurrence and 5 had canceration. Three patients with extrasseous/peripheral type underwent expanded resection and two underwent curettage，none of them had recurrence. One patient with metastasizing ameloblastoma recurred after extended resection., Conclusions: Maxillary ameloblastoma with unicystic type should be completely removed with minimal trauma. The recurrence rate of maxillary ameloblastoma via simple curettage or extended resection is still relatively high, which may be due to the large tumor involvement scope of these patients and the failure of complete tumor removal by curettage. For external/peripheral ameloblastoma and metastatic ameloblastoma, the involved jaw bone should be removed as much as possible to prevent recurrence. For malignant transformation of ameloblastoma, the tumor and jaw bone should be dissected during the operation to reduce recurrence rate. The primary site, cervical lymph nodes and lungs should be closely followed after operation to detect early metastasis.