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Based on drilling and logging data, as well as geological experiments, the geological characteristics and factors controlling high-yield and enrichment of hydrocarbons in ultra-deep clastic rocks in the Linhe Depression, Hetao Basin, are studied. The results are obtained in four aspects. First, the inland saline lacustrine high-quality source rocks developed in the Paleogene in the Linhe Depression have the characteristics of early maturity, early expulsion, high hydrocarbon yield, and continuous and efficient hydrocarbon generation, providing an important resource basis for the formation of ultra-high pressure and high-yield reservoirs. Second, the weak compaction, early charging, and weak cementation for pore-preserving, together with the ultra-high pressure for pore-preserving and fracture expansion to improve the permeability, leads to the development of high-quality reservoirs with medium porosity (greater than 15%) and medium permeability (up to 226×10−3 μm2) in the ultra-deep strata (deeper than 6 500 m), which represents a greatly expanded space for oil and gas exploration. Third, the Linhe Formation adjacent to the trough exhibits a low net-to-gross (NTG) and good reservoir-caprock assemblage, and it is overlaid by very thick high-quality mudstone caprock, which are conducive to the continuous and efficient hydrocarbon generation and pressurization and the formation of ultra-high pressure oil and gas reservoirs. Fourth, the most favorable targets for ultra-deep exploration are the zones adjacent to the hydrocarbon generating center of the Paleogene Linhe Formation and with good tectonic setting and structural traps, mainly including the Xinglong faulted structural zone and the Nalinhu faulted buried-hill zone. The significant breakthrough of ultra-deep oil and gas exploration in the Linhe Depression reveals the good potential of ultra-deep clastic rocks in this area, and provides valuable reference for oil and gas exploration of ultra-deep clastic rocks in other areas.

ObjectiveTo investigate the effect of multi-joint functional electrical stimulation (FES) combined with conventional rehabilitation therapy on lower limb motor function of patients with stroke.MethodsA total of 35 patients with lower limb motor dysfunction after stroke were admitted to the Department of Rehabilitation Medicine in the Huashan Hospital, Fudan University from January to December 2023. The patients were randomly divided into control group and experimental group by SPSS 25.0 statistical software, with 16 and 19 cases in each group, respectively. During the course of the treatment, one case in the control group dropped out due to early discharge, four cases in the experimental group discontinued or dropped out for various reasons, and finally 15 cases were included in each group. The control group received routine rehabilitation treatment and routine walking training. Routine rehabilitation treatment included stretching training, muscle strength training, joint mobility training, motor control training and functional mobility training for transfer, 40 minutes a time, once a day, five times a week for four weeks; routine walking training included pelvic control training, knee joint stability training, balance training, up and down stairs training, 20 minutes a time, once a day, five times a week for four weeks. The experimental group received multi-joint FES treatment in addition to the conventional rehabilitation treatment received in the control group, 20 minutes a time, once a day, five times a week for four weeks. Before treatment, two and four weeks after treatment, Fugl-Meyer assessment lower extremity (FMA-LE) was used to assess lower limb motor function; the JiBuEn three-dimensional gait analysis system was used to assess the walking speed, stride length, double support phase (the stage of the gait cycle in which both feet landed simultaneously), and average knee flexion and extension angles (the average of the maximum knee flexion and extension angles); the modified Barthel index (MBI) was used to assess the activities of daily living.Results(1) FMA-LE and MBI scores: compared with that before treatment, the FMA-LE and MBI scores of both groups increased significantly after two and four weeks of treatment, with statistically significant differences (PPPPPP

Aiming at the problem of error in deep-sea DOA(Direction of Arrival, DOA) estimation based on plane wave sound field model, this paper establishes the array signal model of deep-sea DOA estimation under multipath channel based on ray theory. The characterization method of deep-sea multipath ray propagation time and adjacent array element ray propagation delay difference are also derived. Compared with the propagation delay difference expression of adjacent array elements in the traditional plane wave model, the propagation delay difference expression of adjacent array elements derived in this paper is more universal. Combined with the decoherence DOA estimation algorithm, the performance of deep-sea DOA estimation is improved, and the effectiveness of the algorithm is verified by simulation. The research shows that the time delay difference between adjacent array elements is not only related to the distance between array elements and the target azimuth, but also related to the depth of the sound source and the horizontal distance from the sound source to each array element. The construction of the steering vector in DOA estimation should consider the influence of these factors. At this time, DOA estimation is a multi-dimensional parameter optimization problem. Fully considering the acoustic propagation characteristics of the ocean sound field can fundamentally solve the error problem of deep-sea DOA estimation.

The change of water occurrence form and content in coal will change the physical characteristics and pore structure of coal, and then affect its crushing process.In order to study the effect of moisture contained in coal on on the crushing behavior of coal particles,anthracite coal was used as the research object. A Hastelloy grinding equipped with a power measuring device was applied to simulate the crushing environment in a medium-speed coal mill. The individual and mixed crushing experiments were carried out in multi-time batches of coal samples with different water content. Thus, the effects of water occurrence on coal crushing rate, pulverized coal fineness, and grinding energy consumption were studied. The experimental results showed that compared with the original coal samples, the initial particle size material crushing rate of homogenized soaked coal samples decreases significantly due to the increase of water content, its grindability index first decreased and then increased with increasing the water content when the homogenized immersed coal sample was crushed separately, and the fineness of pulverized coal t10 was positively correlated with water content. When dry and wet coal samples were mixed and crushed, the crushing rate and fine-grained material generation rate of 13.34% moisture content samples were much higher than that of homogenized soaked coal samples with the same moisture content, and their its grindability index was larger than that of the original coal; The grindability index of the blended coal samples with other moisture contents was slightly smaller than that of the homogenized soaked coal samples, and this difference became larger with the increase of moisture content, while the crushing rate and the yield of fine-grained materials differed less from that of the homogenized impregnated coal samples. Also, the result indicated that the classical energy-particle size relationship model may be used to characterize the individual and mixed crushing processes of samples with different moisture gradients. The internal and external moisture reduced the ability of anthracite to resist crushing to varying degrees, and increasing the water content during separate crushing improved the energy efficiency significantly. So, the water content parameters were introduced into the energy consumption model to characterize the crushing process of various moisture coal samples. By exploring the influence mechanism of water content in coal on energy consumption of coal crushing, it reveals the way of energy loss in the process of coal crushing and provides theoretical guidance for optimizing coal crushing process and reducing energy consumption.

Two bearing-only maneuver detection methods based on deep learning are proposed to address the problems of long detection delay and low accuracy of existing bearing-only maneuver detection methods for underwater targets. The bearing observations of the target in the constant velocity (CV) motion state and constant turning (CT) motion state are used as the training data set. The target motion pattern classification and bearing prediction are realized through the Long short-term memory (LSTM) neural network, and then realize the maneuver detection of underwater targets based on motion pattern classification and bearing prediction. The simulation results show that compared with the traditional bearing prediction maneuver detection method, this method reduces the bearing observation error and has a lower sensitivity of target maneuver magnitude, and has a higher maneuver detection accuracy and reduces the maneuver detection delay.

Grinding experiments of coal are designed to study the influence of spherical and cylindrical media on the three-dimensional morphology characteristics of grinding products. Details of experiments consist of coal grinding, screening of grinding produces, non-destructive testing of coarse-grained coal based on high-resolution three-dimensional X-ray microscopic imaging system, and particle segmentation extraction and three-dimensional morphology feature parameter calculation based on the Dragonfly software. For the low rotation rate condition of the ball mill, if the total surface area or total mass of grinding media is the same, breakage rate of the top size particles ground by the grinding ball is higher than that of the cylindrical media. Moreover, the yield of −1 mm fines yielded by the ball is the highest. The grinding effect reduces the volume and surface area of coarse materials. For the three grinding conditions, the steel cylindrical media with the largest surface area has a more significant “grinding and stripping” effect on coal and the highest particle sphericity.

Peaches are an ancient fruit in China, with great nutritional and commercial value. Peach fruit is a typical respiratory climacteric fruit, which is prone to browning within a short period of time after harvesting, and rapid browning and high browning degree occur during peach processing, which are difficult to control, affecting the quality and economic value of the fruit. At present, systematic research on the characteristics and mechanism of peach browning is lacking, as well as effective control techniques and methods. In this paper, the current status of research on the characteristics and mechanism of and the key factors for enzymatic browning in peach fruit is reviewed, and the techniques used for its control are summarized, aiming to provide a reference for the regulation of enzymatic browning during peach storage and processing and consequently to promote the quality improvement of fresh and processed peach products.

The existing methods for the determination of phosphorus content are unable to regulate the addition of acid and base in the refining process of crude soybean oil through real-time monitoring. Therefore, a novel rapid method for determining the phosphorus content of crude soybean oil based on near-infrared spectroscopy was proposed in this study. It was found that standard normal variate transformation was more effective than two other spectral preprocessing methods evaluated for denoising the spectral data indicative of the phosphorus content in soybean crude oil. The characteristic absorption band of phosphorus was optimized by synergy interval partial least squares (SiPLS). A back propagation (BP) neural network prediction model of the phosphorus content in crude soybean oil was established with learning efficiency of 0.005 and 108 training cycles. The determination coefficient (R2), root mean square error (RMSE) and relative standard deviation (RSD) for the correction set were 0.979 7, 0.859 3 and 1.89%, respectively. The R2, RMSE and RSD for the validation set were 0.978 5, 0.963 8 and 2.15%, respectively. The above results showed that NIR spectroscopy can achieve rapid, accurate and non-destructive detection of the phosphorus content in, and provide a feasible method for the refining of crude soybean oil.

Guangxi Mulun National Nature Reserve is located in the crisscross zone of Dian-Qian-Gui flora and south China flora, also is the heartland of the transition zone about Palaeoarctic flora and Palaeotropical flora. It plays an irreplaceable role in biodiversity conservation areas of China. In order to explore the plant species diversity in Guangxi Mulun National Nature Reserve, the composition and characteristics of vascular plant diversity was studied based on historical literatures, field investigations, specimens collection and identification, and data statistical analysis. The results were as follows: (1) This reserve had 1 735 species of vascular plants, including 218 species of lycophytes and ferns, 1 517 species of seed plants, with abundant vascular plant diversity and complex floristic composition. (2) This reserve had 486 species endemic to China, 56 species endemic to Guangxi, and 262 species endemic to karst areas, with significant plant endemism. (3) This reserve had 68 species of national key protected wild plants, 153 species of Guangxi key protected wild plants, 4 species of extremely small population wild plants in China, 108 threatened plants, and 144 plants listed in the appendix of the Convention on International Trade in Endangered Species of wild Fauna and Flora (CITES), with relative high degree of rare and endangered plants. Based on the results, Guangxi Mulun National Nature Reserve is an important gene bank of karst plants. It has extremely important conservation value. This study also provides important basic data for construction and management of this Reserve, protection and sustainable utilization of plants, and other scientific research works.

Based on paleogeomorphology, drilling and seismic data, this paper systematically studies the structural and sedimentary evolution, source rock characteristics, reservoir characteristics and formation mechanism, hydrocarbon accumulation model and enrichment law in the Linhe Depression of the Hetao Basin, NW China. The Hetao Basin mainly experienced three stages of evolution, namely, weak extensional fault depression, strong extensional fault depression and strike-slip transformation, giving rise to four positive structural belts (Jilantai, Shabu, Nalinhu and Xinglong), which are favorable areas for oil and gas accumulation. The two main saline lacustrine source rocks, Lower Cretaceous Guyang Formation and Oligocene Linhe Formation, are characterized by high sulfur content, rich algae, early maturity, early expulsion, and wide oil generation window. The large structural transition belt in the intermountain area around the Hetao Basin controls the formation of large-scale braided river delta deposits, which are characterized by high quartz content (50%–76%), long-term shallow burial and weak compaction, low cement content, and good reservoir properties in delta front sandbody. The burial depth of the effective Paleogene reservoirs is predicted to reach 8000 m. Three hydrocarbon accumulation models, nose-uplift near sag, buried hill surrounding sag, fault nose near source rock, are constructed. The law of hydrocarbon accumulation in the Linhe Depression is finally clarified as follows: near-source around the depression is the foundation, high-quality thick reservoir is the premise, good tectonic setting and trap conditions are the key.

The Taixi anthracite was used as the raw materials, and mixed with different masses of additives, namely silicon oxide, titanium oxide, and iron oxide, to prepare the coal-based graphite by high temperature graphitization. The microstructure of coal-based graphite was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), laser confocal Raman spectroscopy (Raman) and Specific surface area and porosity analyzer.The results show that the graphitization degree of the coal-based graphite can reach over 89% after high temperature heat treatment at 2800 °C , which significantly improves the microcrystalline structure of anthracite and achieves orderly rearrangement of sp2 hybrid carbon atoms in the coal. Under the same additive mixing level, the graphitization degree and stacking height of coal-based graphite with titanium dioxide as additive are relatively high, the difference between the layer spacing and the ideal graphite layer spacing is the smallest, and the degree of ordering of carbon materials is the highest. The Raman spectroscopy results showed that the order degree of coal -based graphite prepared under different additives was significantly different, and the order degree of TXSC3, TXTC2 and TXIC3 coal-based graphite was the highest among the additives. Under the electron microscope, it is found that under the conditions of three additives, the scales, spherical and two shapes of coal-based graphite can be prepared separately. It can be seen from the specific surface area and pore size distribution data of coal-based graphite that they have similar low-temperature nitrogen adsorption-desorption isotherms.

In order to solve the problem of thermal deformation of brazed saw blade substrate under high temperature, the temperature, the microstructure and the stress-strain field of local induction brazed saw blade substrate were analyzed with the finite element software, and the factors affecting the deformation of saw blade substrate were studied. The results show that the phase transformation of the saw blade substrate is mainly distributed on the brazing working surface. After cooling to room temperature, three microstructures including ferrite, pearlite, bainite and trace martensite are obtained. When the scanning speed of the heat source increases, the deformation and the residual stress of the substrate increase. When the scanning speed increases from 0.25 mm/s to 2.00 mm/s, the thickness of the phase change layer decreases from 5.8 mm to 4.7 mm, the maximum deformation increases from 0.41 mm to 0.82 mm, and the residual stress increases from 482 MPa to 667 MPa. The test results are basically consistent with the simulation results.

Background and purpose: Recent evidence suggests that N6, 2'-O- dimethyladenosine (m6Am) modifying enzyme phosphorylated C-terminal domain-interacting factor 1 (PCIF1) may be an important biomarker/therapeutic target in gastric cancer. However, the relationship between this novel PCIF1 molecular mechanism and gastric cancer progression remains to be further explored. In this study, we analyzed the regulatory role of PCIF1 on gastric cancer proliferation, migration and invasion and the mechanism of its regulatory target gene ACOT8 in gastric cancer progression. Methods: PCIF1 expression in gastric cancer and non-gastric cancer tissues of gastric cancer patients was analyzed using Gene Expression Profile Interaction Analysis (GEPIA), and the correlation of PCIF1 expression with overall survival in gastric cancer patients was analyzed. We collected all gastric cancer tissues and matched para-cancerous tissues from 89 primary gastric cancer patients treated in Department of Gastroenterology of Changsha First Hospital from 2019 to 2021. PCIF1 expression was analyzed by real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR) and Western blot. In in vitro experiments, SNU5 cells were divided into PCIF1 knockdown (sh-PCIF1) group and corresponding control (sh-NC) group, and AGS cells were divided into vehicle as normal control (NC) group and PCIF1 overexpression (PCIF1) group. The effect of PCIF1 on gastric cancer cell proliferation, invasion and migration was investigated using cell counting kit-8 (CCK-8), EdU and transwell assays. Furthermore, ACOT8 expression was knocked down in PCIF1-overexpressing AGS cells, and rescue experiments were performed. A subcutaneous xenograft model was used to determine the biological effects of PCIF1 in gastric cancer in vivo. Results: PCIF1 expression was abnormally high in gastric cancer tissues and cell lines, with significant correlation between PCIF1 expression and the prognosis of gastric cancer patients. Compared with the sh-NC group, the cell viability, EdU positive cells, migration and invasion cell numbers in the sh-PCIF1 group were significantly decreased (P

Drip irrigation has been increasingly used not only for watering cash crops but also for stable crops in water-scarcity regions. One common problem in drip irrigation is emitter clogging, especially when using reclaimed water which is rich in nutrients and microbes. This paper reviews the recent development in biological clogging of the emitters, including its cause and mitigation. It is based on literature review of the extensive publications over the past decades. We review the current research situation both nationally and internationally and outline the cause of the clogging when using reclaimed water for irrigation, especially the underlying mechanisms. We also review the measures for anti-clogging the emitters. From these, we discuss the potential development in this area, including remediation of biological clogging using chlorination, adjusting flow rate and drip irrigation frequency, and the applications of these specific measures to different regions and situations.

Microencapsulation of essential oils can provide sustained release properties of their products. The reasonable selection of microcapsule wall materials is considered to be the key to effectively controlling the action time of essential oils and improving the stability of the products. From the classification of proteins and polysaccharides, the research status of the wall materials of sustained-release microcapsule of essential oils are summarized, and their development trend and prospects are introduced. It is expected to provide a useful basis for the research and industrial production of essential oil microcapsules in food industry and other related fields.

Using minute precipitation data from 1980 to 2017 of Changsha, the sensitivity of changes in precipitation events with time interval was experimented. On the basis of the establishment of precipitation interval 240 minutes, the characteristics of precipitation events in Changsha were analyzed for five aspects including the rainfall occurrence and amount, the start time, end time, duration, and break interval from March to November, March to June, and July to September. The analysis shows that there are about 121 precipitation events from March to November and 68 precipitation events from March to June and 32 precipitation events from July to September. The start time and end time of precipitation events show different daily variation characteristics with different seasons and rainfall thresholds. The duration for most precipitation events is less than one hour and 76% is below 12 hours. The frequency of events with break interval less than 12 hours is about 46%. Precipitation events lasting over 24 hours account for about 39%.

Double-propeller compound high-speed unmanned helicopter, which is currently one of the hottest research topics in high-speed aircraft, has the advantages of both helicopter and fixed wing aircraft. In this paper, the flight-dynamics related analysis and manipulation strategy research of the double-propeller compound high-speed unmanned helicopter are carried out. The aerodynamic interference model of rotor to wing is constructed by using the interference factor, and the fuselage model is based on the wind tunnel test data. Then, the nonlinear flight dynamics model of double-propeller compound high-speed unmanned helicopter is presented. In view of the problem of control redundancy, a manipulation strategy is proposed, which allocates the control channel with the weight coefficient, and controls the forward flight speed by the longitudinal channel of the mean propeller pitch. On this basis, the smooth transition of each rod between the three modes is realized, which verifies the rationality of the control strategy. [ABSTRACT FROM AUTHOR]

Using the Gleeble-1500D simulator, the high temperature plastic deformation behavior of 40%SiCP/Al-Cu composite were investigated at 350-500℃ with the strain rate of 0.01-10 s-1. The stress-strain curves were obtained during the tests. The critical conditions of dynamic recrystallization for onset of DRX during deformation of 40%SiCP/Al-Cu composite was obtained by computation of the strain hardening rate (θ) from initial stress-strain data and introduction of the inflection point criterion of ln θ-ε curves and the minimum value criterion of (-∂(ln θ)/∂ε)-ε) curves. The results indicate that the softening mechanism of the dynamic recrystallization is a feature of high-temperature flow stress strain curves of the composites, and the peak stress increases with the decrease of deformation temperature or the increase of strain rate. The inflection point in the ln θ-ε curve appears, and the minimum value of the (-∂(ln θ)/∂ε)-ε) curve is presented when the critical state is attained for this composite. The critical strain decreases with the decrease of strain rate and the increase of deformation temperature. There is linear relationship between critical strain and peak strain, i.e. εc=0.528εp. The predicting model of critical strain is described by the function of εc=4.58×10-3Z0.09. Electron microscopic analysis show that the dynamic recrystallization occurs when the strain is 0.06 (T=400℃, ε=10 s-1), and the dynamic recrystallization grains fully grow up when the strain is 0.2.

Database benchmarking has stimulated the development of data management systems and technologies. In big data environments, benchmarking should be revisited. Therefore, research on benchmarks for big data management systems is a key problem for big data research and applications. Benchmark design can be achieved from three different perspectives, i.e. data, workload, and performance measurements. After the brief introduction to these three elements and the progress of big data management system research, the requirements and challenges to benchmarking big data management systems were analyzed. Through the introduction to a benchmark for analytical queries over social media data, named as BSMA, the issues of design and implementation of a benchmark for big data management systems were discussed.

Platinum dispersion is an important factor affecting the activity of catalytic reforming catalyst. The platinum dispersion of reforming catalyst is generally measured by hydrogen-oxygen adsorption method. Due to high temperature and moisture atmosphere, the platinum on the catalyst will accumulate and the chlorine components wiil be lost, which leads to the deactivation of catalyst. After carbon burning of the deactivation catalyst, it is oxidized and chlorinated to supplement the chlorine, and disperse platinum crystal particles, and restore the catalyst activity. The oxychlorination stage conditions are key factors in restoring platinum dispersion. By adjusting the reaction severity, the carbon deposition is increased from 3. 0% ~ 3. 5% to over 4.0%. Increase the temperature at the inlet of the second charring stage from 480 °C to more than 490 °C, and the bed temperature of the oxychlorination stage is increased from 480 ~490 °C to more than 510 °C. The oxygen volume fraction at the outlet of the second charring stage is reduced from 0.35% to 0.30% to improve the air distribution in the oxychlorination stage, and the oxygen volume fraction in the oxychlorination stage is remained above 5.8%. According to the catalyst circulation rate, the chlorine injection increases from 2,000 µg/g to 2,600 µg/g. The molar ratio of water to chlorine is controlled to 5 - 6. The platinum dispersion of the reforming catalyst is increased from 70% to more than 85% . [ABSTRACT FROM AUTHOR]

Virtual coupling technology has outstanding advantages in improving the efficiency of train operation, alleviating the strain of line capacity, and adapting to the imbalance of spatial and temporal distribution of passenger flow. It is also the frontier of rail research. The train operation oriented to virtual coupling technology is a complex process, which needs to undergo several stages of transformation, such as train coupling, coupling formation and train decoupling. Among them, train coupling and train decoupling are the key to realizing virtual coupling. This paper takes interval coupling and decoupling of trains as the research object and describes the control process of train coupling and decoupling. On this basis, a scheme of running state transition of virtual coupling trains is proposed, and the dynamics analysis of different train motion states in virtual coupling scenarios is carried out. Finally, the advantages of virtual coupling technology in shortening train interval and improving line capacity are verified by simulation. The results indicate that the minimum interval of unit trains in the coupled formation is much smaller than that of the traditional block mode at the same speed, and the difference between them will become larger and larger with the increase of the speed. When the speed is 60 km/h, the minimum safe interval is shortened by 71.7%. In addition, dispatching the trains with high relative braking performance as the following trains will be beneficial to improve the driving efficiency. [ABSTRACT FROM AUTHOR]

To provide reliable data support for quality inspection of fluorite concentrate and environmental supervision, ICP-MS with the matrix-matching method was applied for the determination of trace harmful elements, such as copper, zinc, arsenic, cadmium, and lead. Analytical pure calcium carbonate was firstly dissolved by nitric acid, and the deviation of calcium content measured by ICP-MS to theoretical value was about 6%. The calcium solution was diluted for various ratios to prepare multi-element standard solutions with matrix concentrations of 1 000, 2 000 and 5 000 mg/L. Based on the traditional four acid digestion method, fluorite concentration was digested completely by changing the addition sequence and dosage of acids, and control level of temperature. Digestion with the addition of standard solution, process blank, and blank with the additional standard solution were also set. After the moderate dilution, ion concentration in the digestion solution of fluorite concentration was closet to the optimal one of complex matrix standard solution. In the testing of complex matrix standard solutions and sample digestion solution, collision reaction cell technology within the He mode was used, and 7ZGe, 115 In, and 175Lu were selected as the internal elements. The results showed that the linearity of standard curves for each element was greater than 0. 999 5, and internal standard recoveries of each sample fluctuates was 80. 0%--110%, indicating that the mass and non mass spectrometry interferences were eliminated well by the matrix matching and correction of internal standard during the measurement of complex solution. Excessive elemental precipitation or volatilization loss did not happen in digestion experiments, and the recoveries of harmful elements in samples with the addition of standard solution were 90.0%--120%. Testing error of the content of each element in quality control sample was within 15%. The detection limits for copper, zinc, arsenic, cadmium, and lead were 4. 81, 8. 65, 17. 91, 0. 49 and 2. 84 jug/L, respectively, which can meet the accurate measurement demand for contents of trace elements in samples with complex matrix. [ABSTRACT FROM AUTHOR]

Understanding the spatial heterogeneity of soil available medium- and micro-elements in karst area can provide a valuable theoretical guideline for soil nutrient management of karst ecosystem. We collected soil samples at a soil depth of 0-10 cm using grid sampling (20 mx20 m) in a 25 hm² (500 mx500 m) dynamic monitoring plot. We further analyzed the spatial variability of soil medium- and micro-elements and their drivers, with classic statistics analysis and geo-statistics analysis. The results showed that the average contents of exchangeable Ca and Mg and available Fe; Mn; Cu> Zn; and B were 7870; 1490; 30.24; 149.12; 1.77; 13.54. and 0.65 mg ⋅ kg-1; respectively. The coefficient of variation of the nutrients ranged from 34.5% to 68.8%; showing a medium degree of their spatial variation. The coefficient of determination of the best-fit semi-variogram models of each nutrient was higher than 0.90, except for available Zn (0.78), indicating a strong predictive power for the spatial variation of the nutrients. The nugget coefficients for all the nutrients were less than 50%, showing a moderate spatial correlation, and the structural factors played a pivotal role. The spatially autocorrelated variation was within the range of 60.3-485.1 m, among which available Zn showed the lowest range and the deepest fragmentation degree. The spatial distribution of exchangeable Ca, Mg, and available B were consistent, with contents in the depression being significantly lower than that in other habitats. The contents of available Fe, Mn, and Cu declined with the increases of altitude and were significantly lower on the hilltop than in other habitats. The spatial variation of soil medium- and micro-elements was closely related to topographic factors in karst forest. Elevation, slope, soil thickness, and rock exposure rate were the primary drivers of spatial variation of soil elements and need to be considered in soil nutrient management of karst forestlands. [ABSTRACT FROM AUTHOR]

Blockchain could achieve trustworthy ledger management without central node.It has been successfully supporting financial applications such as Bitcoin.The essence of blockchain is trusted data management in an incompletely trusted environment.It has such features as decentralization,anti-tampering,strong consistency and integrity.On the other hand,blockchain also suffers the problem of weak data management functions,low performance and other issues.By comparing blockchain with traditional data management techniques and analyzing the three applications of blockchain beyond the financial fields,new research issues on blockchain were explored.The requirement for design and implementation of sharing database systems for specific application domains was discussed.The sharing database can be simply defined as a database that supports mission-critical applications,the sharing economic business model,and even itself is implemented in a sharing economy manner.

Prosimetrum is the most unique narrative feature in the early 20th-century Kazakh novels. The narrative function and ethical value of verse are mainly shown in three aspects: first, the verse clearly has a critical function to clarify the ethical persuasion and moral position of the novel; second, its performance function promotes the construction of a new moral code while pandering to the implied audience of the novel; third, its lyrical function prompts the protagonist to denounce the feudal morality on behalf of women, which triggers a strong response from the audience and further contributes to the achievement of the ethical goals of the novel. The multi-layered narrative function and ethical value could only result from the joint effect of Kazakhstan's oral literary traditions, the author's ethical goals, and public reception norms, which reflects the overall style of the Kazakh literature during its social transformation. [ABSTRACT FROM AUTHOR]

Iron tailing and cement were used to modify the raw soil, 10 groups of formula were designed by using the simplex lattice formula design method. Using the raw soil samples as the control group, the damage patterns, compressive strength, deformation and stress-strain curve of the new material of each group of specimens were investigated, and the reasons for the failure of the specimens, as well as the influence law of modified material content on strength, discreteness and stress-strain curves were analyzed. The test results showed that the variation law of stress-strain curves obtained from each designed formula were similar, while the slope and discreteness of the curves were different. The increase of iron tailings and cement could improve the compressive strength of the raw soil material as well as its dispersion. Frequency analysis revealed that the compressive strength of the enhanced raw soil material reached a value between 6 MPa and 9 MPa with a 95% guarantee rate when the content of iron tailings, cement and raw soil set at 12.1%~19.5%, 13.9%~19.1% and 65.5%~69.9%, respectively. [ABSTRACT FROM AUTHOR]

Recently,graph data has been widely used in domains such as information security,scientific research,internet services,etc.,that stimulates the fast development of graph data management systems.However,existing benchmarks for graph databases are all designed for applications that manage and analyze social networks.The statistical characteristics of knowledge graphs were analyzed,and compared with two social networks.It was showed that knowledge graphs,as an important and fast growing kind of graph data,were significantly different from social networks.Therefore,existing social network based benchmarks were not suitable for applications that deal with knowledge graphs.Furthermore,the requirements for a new benchmark were analyzed.

There are some characteristics for IT development in the big data era:the real-life applications are the driving force for innovation; open sourcing accelerates innovation,and the advancement in hardware lay the foundation for innovation.The data sciences and engineering was regarded as an emerging and developing interdisciplinary and discussed from the aspects such as social innovation and development,talents demand changes,and technology development.Then the features,connotations,and knowledge hierarchy of data sciences and engineering as a discipline were described.Finally,the associated research and development,talent training,and best practice were also presented.

Traditional researches on vehicle rollover mainly focused on untrip rollover when vehicle running on the plat road, and 3DOF (three degree of freedom) model including lateral translational motion, yaw rotational motion and roll rotational motion was used widely. Obviously, the 3DOF model does not consider the influence caused by road excitation. But SUV (Sport Utility Vehicle) and commercial vehicle always run on the rough road, and the vehicle rollover characteristic were influence by the road condition impacts. For exploring the influence of road irregularity on vehicle dynamical rollover characteristic, a combined vehicle model was proposed. The model include six degree of freedom such as lateral translational motion, vertical translational motion, yaw rotational motion, roll rotational motion of vehicular body and two vertical translational motion of tires. The calculation program was built in MATLAB/ Simulink, and the vehicle rollover characteristic response parameters were calculated by Simulink with FISHHOOK test. The right road profile was a sine wave road coupling B grade road, the left road profile was B grade. Then a multi-body dynamical vehilcle model was built in Adams software. And the Adams vehicle model was used to calculate the results under the same work conditions with Simulink model, the results through Simulink model were compared with the values in the simulation test data of Adams model. Through comparison of simulation results, the Simulink model was proved correct. Secondly, the influences on roll angle caused by road grade, vehicle velocity and steering angle velocity were investigated. The results of simulation analysis showed that the simulation results of combined model were more accurate than the data of 3DOF and 4DOF model, the combined model results can consistent with Adams model result. The road irregularity, vehicle speed, steering wheel rotation speed have some effects on the vehicle roll characteristic, the roll angle during the steady state region increases as the rise of road grade, and the value during transient state has not obvious change. Vehicle roll angle increases as the rise of vehicle speed. And only the roll angle during the transient state is susceptible to rotation speed of steering wheel, which presented an augment with the increase of rotation speed. Further, the reason using simulation test on vehicle rollover characteristic research and the application of combined rollover model were discussed. Because of extremely dangerous and high economic cost, the majority research institution and automotive factory use the simulation test instead of on road test for vehicle rollover analysis, and commonly method is constructing multi-body dynamical simulaton model by Adams or LMS.Virtual.LAB/Motion. Then, simulation test was carried out based on the Fishhook and J-Turn test procedure. The application of combined rollover model was closely tied with vehicle control technology, such as differential braking, semi-active/active suspension, active steering, integrated chassis control and so on. These control method needs a state estimation to detect the impending vehicle rollover. Obviously, the accuracy of estimator is important to the control effect. The combined model has more accurate calculation result for vehicle roll angle and roll angle velocity than traditional 3DOF and 4DOF model. [ABSTRACT FROM AUTHOR]

To enhance further the stability of traffic flow, based on the FVD (full velocity difference) model, a new car following model named BL&OVD model is proposed by incorporating the synergy effect of backward looking and optimal velocity difference information. By applying the linear stability theory, the linear stability condition of the new model is obtained and the modified Korteweg-de Vries (mKdV) equation is established with nonlinear analysis to describe the propagating behavior of traffic jam near the critical point. The simulation results show that the amplification of random disturbance signal in traffic flow can be reduced effectively with the new consideration, which means that the proposed approach can stabilize the traffic flow and suppress the traffic congestion. The new model can stabilize the traffic flow further, and help to design the vehicle driving strategy in the autopilot system. [ABSTRACT FROM AUTHOR]

PURPOSE: To investigate the relationship of vertical root fracture (VRF) after root canal treatment with two different technique of root canal shaping and provide clinical reference. METHODS: 1702 teeth treated with root canal treatment during recent 2 years. All teeth were divided into two groups according to different techniques of root canal shaping: 643 teeth were prepared with NiTi rotary preparation technique (NRPT) and 1059 teeth were prepared with stainless steel hand K-files preparation technique (SSI:VF). The clinical symptoms and signs, radiological findings were estimated. The data was analyzed by SPSS 11.5 software package. RESULTS: There were 32 teeth with vertical root fracture, the VRF rate was 1.88%. The VRF rate in NRPT group was significantly higher than in SSPT group (P<0.01). The VRF rate with retreatment history in NRPT group was significantly higher than in SSPT group (P<0.01), but The VRF rate with post and core restoration in both NRPT and SSPT groups was not significantly different (P >0.05). CONCLUSIONS: NiTi rotary preparation technique (NRPT) was closely related with vertical root fracture (VRF). And the VRF risk would be even higher if the tooth underwent root canal retreatment case or a post-core was placed in the root canal. [ABSTRACT FROM AUTHOR]