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In view of the energy occurrence structure of “rich coal, poor oil and little gas” in China, and the situation that coal will occupy the dominant position of energy consumption for a long time,The development history of frozen shaft mechanized drilling and blasting is reviewed in the field of coal mining in China. As the main construction method of shaft construction, the application of dynamite greatly improves the drilling efficiency of frozen shaft. The application of supporting large mechanized equipment such as umbrella drilling, rock grabbing machine loading, large derrick and equipment hoisting, and large formwork building, greatly improve the wellbore completion speed; Shaft drilling rig, reverse drilling rig and shaft boring machine as special shaft sinking methods under special formation conditions, also have their own application range. Aiming at the characteristics of water-rich weakly consolidated formation and the development trend of smart mine in western China, there are shortcomings in using freezing & borehole-blasting method and large drilling equipment to develop the shaft of weakly consolidated formation at kilometer level, while using freezing & shaft boring machine is one of the trends of ultra-deep shaft construction. Combining with the construction cases of freezing & shaft boring machine abroad, reasonable suggestions are put forward for shaft excavation of water-rich weak consolidated rock formation in western China. The freezing wall thickness and strength are calculated according to the current design theory, the permanent shaft support adopts double-layer reinforced concrete wall structure, the rock-breaking form of shaft boring machine under low temperature environment, and the method of hierarchical slag discharge to realize the parallel operation of digging - supporting - transporting. Finally, the next research focus of this construction method is put forward. The synergistic mechanism between shaft wall structure and weakly consolidated surrounding rock should be clarified to realize optimization of shaft wall structure, and the support - operation cooperation mode of shaft boring machine to improve shaft excavation and support efficiency and improve informatization level. Realize shaft driving towards mechanization and intelligence.

Since low-light images are of poor quality and carry noise, resulting in insufficient contrast and brightness, unclear details in the image, and the problem of high cost of obtaining paired low-light image datasets, a no-reference low-light image enhancement method for feature map enhancement is proposed under the influence of the Mach band effect of biological vision. Firstly, the model uses the enhanced filter block (EFB) to enhance the feature of images and feature maps, which can suppress noise and enhance the feature details to improve the ability of the network to learn features. Then, skip connection is combined with efficient spatial attention (ESA) module to extract global context information and local regional features by fusing enhanced shallow features and deep features, which effectively retains image color information, avoids detail loss, and improves the generalization ability of the network. Finally, the pixel estimation curve is used to adjust the dynamic range of the pixels in the low-light image and enhance the brightness of the low-light image. Experimental results show that the PSNR, SSIM, LPIPS and NIQE of the image processed by the algorithm reach 17.709 dB, 0.657, 0.239 and 3.486 respectively. Compared with the existing mainstream algorithms, it can better achieve the purpose of image enhancement, and effectively improves the image brightness and detail information, while maintaining the naturalness of the image.

In this work, a novel graphite-based electrochemical filter was developed for the efficient and environmentally friendly treatment of uranium tailings leachate. The filter utilizes graphite particles as filler and carbon felt as a conductor, powered by a DC power supply and driven by a peristaltic pump. In a non-circulating continuous operation filter experiment, uranium tailings leachate was tested for uranium removal efficiency under different operating parameters such as voltage and residence time, using both synthetic wastewater and actual uranium mine wastewater. This study is based on the fundamental principles of metal electrochemical reduction. The efficacy of this device for the continuous flow treatment of uranium tailings leachate was systematically investigated. The mechanism of uranium tailings leachate treatment by the electrochemical filter was elucidated through electrochemical analysis and product characterization. The results highlight that voltage and hydraulic retention time are critical factors influencing the efficiency of electrochemical filter treatment. Specifically, 4.0 V and 10 hours were identified as the optimized voltage and suitable hydraulic residence time, respectively, for the treatment of uranium tailings leachate using the electrochemical filter, resulting in a uranium removal rate exceeding 97%. In actual uranium tailings leachate applications, the maximum extraction rate can reach 5275 μmol/(m3∙h), confirming the feasibility of electrochemical filter in removing uranium from actual uranium tailings leachate and its good selectivity in complex water quality applications, the device can be quickly applied to uranium tailings leachate collection facilities and achieve in-situ uranium extraction. The voltage increase can significantly enhance the uranium extraction performance and can be portablely deployed in uranium mine water. In-situ uranium processing and recovery is achieved in processing and collection facilities. Characterization techniques such as field emission scanning electron microscope-energy spectrum analyzer(FESEM-EDS) and X-ray photoelectron spectrometer(XPS) were employed to analyze the reaction products on the graphite particles, revealing that uranium was evenly distributed on the surface of graphite particles and exhibits a stable crystal structure, the main mechanism responsible for uranium removal was adsorption-reduction, with uranium recovery products deposited on the electrode surface in the form of a mixture of U(Ⅳ) and U(Ⅵ). A cost estimation shows that the operational cost of extracting uranium from uranium tailings leachate using this device falls within the range of 176.6 ￥/kgU to 587.5 ￥/kgU. This cost is significantly lower than that of conventional land-based uranium resource development, making it economically viable. This research provides both theoretical and technical support for the efficient and environmentally friendly treatment of uranium tailings leachate.

Aiming at the frost heave characteristics of long-distance and large-section underground freezing projects in cities, the double-line tunnel of Shanghai Metro Line 18 undercrossing an operation station was select as an example,a three-dimensional numerical model was established by using finite element software based on the thermal-mechanical coupling equation. Combined with the physical parameters obtained from laboratory tests, the evolution law of frost heave displacement field of the project was studied, and the influence of measures such as the staggered peak freezing and the adjustment of brine temperature on the frost heave displacement field was explored. Under the experimental conditions, the results show that: ① the deformation of the station floor caused by frost heave which mainly occurs in the active freezing period. When the double-line tunnel is frozen at the same time, the vertical displacement of the station floor at 45days of freezing reaches 77.72% of the displacement at 90 days of freezing. ② When the freezing time reaches 90 days, compared with simultaneous freezing, the displacement of the station floor reduced by 7.7% under the condtion of staggered peak freezing. The superposition effect of frost heave in the same time period is effectively avoided, and the frost heave effect is reduced to a certain extent. ③ When the freezing time reaches 90 days, compared with simultaneous freezing, the displacement of the station floor reduced by 34.2% under the condtion of adjusting the brine temperature, it shown that the expansion rate and frost heave effect of frozen soil are effectively controlled. In engineering practice, measures such as staggered freezing and adjusting brine temperature are used together to control frost heave, and the maximum vertical deformation of the station floor is 25.41 mm. The deformation law of the station floor obtained by numerical simulation is basically consistent with the measured data, which effectively guided the construction of the project.

In order to investigate whether adding a small amount of Al in a low oxygen pressure and high temperature environment has a synergistic effect ontheformationof aprotective Cr2O3oxidefilm on Co-Rebased hightemperature alloys，the isothermaloxidation behaviorofthe Co-20Re-25Cr-7Al alloy was studied under 3.0×10-5Pa O2at 1100～1 300 ℃for24h.Resultsshowed thattheoxidation kinetics curve of the alloy conformed to parabolic law quite well，with the value of oxidation activation energy of 242.3 kJ/mol.The oxidation film formed at 1 100～1 300 ℃were very similar and mainly composed of continuous and dense Cr2O3 layer，covered by a small amount of CoO and CoCr2O4 spinelle.The protective Cr2O3 layer could prevent the evaporation of Re element of alloy in the form of ReO3during the oxidation process，and thus provided better protection for the Co-20Re-25Cr-7Al quaternary alloy，as compared with the corresponding Co-20Re-25Cr ternary alloy，thus providing better protection for the alloy.The addition of 7% Al was not enough to result in the selective external oxidation of Al in Co-20Re-25Cr-7Al alloy，thus forming an internal oxidation zone of Al below the outer oxidation film.However，the addition of Al promoted the formation of continuous and dense Cr2O3 layer，and improved the high temperature oxidation resistance of the alloy greatly.The addition of Al and low oxygen pressure showed a synergistic effect on the formation of a protective Cr2O3 layer.

Around the vision of ＆quot;full coverage＆quot; of the new generation of mobile communication system (6G), satelliteterrestrial integration, as one of the key technologies, is the development direction of the future wireless communication system.The construction of satellite-terrestrial integration network and deep integration need reasonable waveforms at physical layer.In view of the problems of transmission in satellite-terrestrial integration, the signifi cant advantages and practicability of continuous phase modulation (CPM) signal in spectral effi ciency and energy effi ciency were analyzed.The research progress of CPM signal at receiver in mobile communication system from the time and frequency domain were discussed, which provided support for CPM related research in satellite-terrestrial integration in the future.

Objective To study the characteristics of voluntary apheresis platelet donors in Zhoushan Islands and its influence on the collection and supply of apheresis platelets. Methods From January 1, 2017 to December 31, 2021, 1038 eligible donors were selected out of 1151 apheresis candidates for demographic analysis, donation time analysis, blood routine test. We also investigated whether the current supply of apheresis platelet met the needs of clinical. The lapsed donors(with only one donation) were telephone interviewed to investigate the lapsing reasons. Results From 2017 to 2021, the median (M) ratio of platelet donors to the population in Zhoushan City was 0.454 ‰. And 90.18% (1038/1151) of the candidates completed donation, involving 2659 donations and 3205 U products. The per capita donation amount was (1.29±0.77) U per person, which basically met the blood demand in clinical of Zhoushan Islands. The 1038 platelet donors were 18 to 59 yeas old[M(QR) 34(16)], and 47.50% (493/1038) of them aged 31 to 45; the ratio of male to female blood donors was 2.0∶1; 70.61% (733/1038) had college education or above; ABO blood group profile was A>O>B>AB. There were several peak periods of donation during 2017~2021: the second and third quarters of 2017~2019 and the third quarter of 2020; none in 2021, as yeae 2021 was volatile. The donation proportion of the first quarter was the lowest throughout 2017~2021. In 2017 and 2018, the proportion of donors with one donation accounted for 79.79% (75/94) and 51.63% (95/184), respectively. From 2019 to 2021, the proportion of donors with twice or more donation accounted for 60.35% (137/227), 57.36% (187/326) and 53.13% (170/320) , respectively. During 5 years, 10.88% (113/1051) of the candidates failed to donate platelets, of whom 72.57% (82/113) were due to unqualified pre-donation testing. Conclusion The donation behaviors in Zhoushan have been affected by each above-mentioned demographic factors. The awareness of donation and donation services in Zhoushan have been improved as combing the special geographic condition and demographic characteristics together, and the donation units is elevating yearly which has met the clinical needs of the whole island.

The Albertine Basin is an important rift basin in the East African Rift System, enriched in oil and gas resources. The upper Miocene to lower Pliocene hydrocarbon source rocks are important source rocks in the basin, but the research is relatively limited. In this work, we evaluate the source rocks of the upper Miocene and lower Pliocene in the Albertine Basin by integrations of geological, rock pyrolysis and elemental geochemistry data and analyses the paleoenvironmental evolutions of the late Miocene to early Pliocene. These results show that the two sets of source rocks are under the mature stage, but the abundance and type of organic matter are different. The lower Pliocene source rocks have higher organic matter abundance and belong to middle-good source rocks, yielding type Ⅱ1 -Ⅱ2 kerogen. The upper Miocene source rocks have lower organic matter abundance and belong to poor source rocks, yielding type Ⅱ2-Ⅲ kerogen. The sedimentary environment is an important controlling factor for the difference in source rocks. During the late Miocene to early Pliocene, the study area was a freshwater lake with strong reducibility, gradually increasing water depth, a warmer climate, flourishing bacteria and microorganisms, and better organic matter types. At the same time, lake productivity is elevated, the sedimentation rate is accelerated, and organic matter can be preserved more efficiently, so the abundance of organic matter in source rocks is higher.

This paper aims to introduce the application of neural networks in the motion control of unmanned vehicles in recent years. With the breakthrough of computer, robot control, and sensing technology, the development of unmanned vehicles has entered a stage of rapid development. It can reduce driver mistakes, bring convenience to the daily travel of humans, and it is widely used in the military and dangerous fields. However, the unmanned vehicle itself has strong nonlinearity, signal delay, and parameter uncertainty and its control is affected by external factors such as the change of road adhesion coefficient and lateral wind. Therefore, traditional control methods often face challenges in controlling the vehicle stably and accurately. The learning, adaptive, and approximate nonlinear mapping abilities of neural networks provide an effective way to solve the problems of vehicle model parameter uncertainty change, external disturbance, and vehicle adaptive control. Therefore, it is increasingly applied to the motion control of unmanned vehicles. The self-learning and adaptive ability of neural networks enable them to calculate the direct output control quantity according to the state deviation of the vehicle, which can be used as the controller of the unmanned vehicle. The ability of the neural networks to approach a nonlinear mapping makes it possible to approach the unknown dynamic parts of the vehicle, such as the uncertain parameters and external disturbances, which improves the accuracy and robustness of the controller design. The neural networks can remember previous information that can be used to calculate the current output. Thus, the neural networks can be used as the vehicle state observer to estimate the vehicle state parameters. The adaptive ability of the neural networks enables them to optimize the parameters of other control algorithms online. From these aspects, this paper summarized and classified the achievements and progress made by domestic and foreign scholars in applying neural networks to the motion control of unmanned vehicles in recent years, introduced the application situation, and evaluated the advantages and disadvantages. Finally, the main problems of neural networks in the motion control of unmanned vehicles were summarized and the possible development direction was prospected.

Because of the complex vibration caused by various excitations， the transmission is not only related to driving comfort， but also has an important influence on the life and reliability of the transmission system. Considering the excitation source of the transmission and the mode of internal parts and external shift control can effectively improve the vibration problem of the transmission in the early design and development stage. Through a case analysis of mechanical transmission gear early abnormal wear and tear caused by the shifting handle jitter， it is deduced that the shaft assembly and balance block are resonant due to the excitation of the main reduction gear based on the vibration characteristics. The improvement strategy are proposed and verified by experiments.

Ternary rare earth coordination chain transfer polymerization system of neodymium 2,5-dimethyl-2-ethylcaproate / diisobutyl aluminum hydride / dichlorodimethylsilane was used, and the ring opening polymerization of dicyclohexlactone 4,4ˊ- dioxane heptyl-7,7ˊ- dione (BOD) was successfully initiated, the star polybutadiene with polyester cross-linked core structure was prepared. The results showed that the weight average molecular weight of the star polymer increased gradually with the increase of the amount of BOD in the polymerization reaction. At the same time, due to the inconsistent number of arms of the star polymer, the molecular weight distribution became wider. In addition, the Mark-Houwink equation parameter α of star polybutadiene were obtained. It is significantly smaller than linear polymer, but agreed well with the α of traditional star polymer.

Concerning the continually perceiving performance of virtual access points (VAP) was urgent in software-defined wireless network (SDWN),with the features of VAPs’ measurement data (VMD),a self-adaptive matrix completion algorithm based on random walk was proposed,named RW-MC.Firstly,the discrete ratio and covering ratio of VMD account for a sample determination model was used to claim initial samples.Secondly,random walk model was implemented for generating sampling data points in the next iteration.Finally,a self-adaptive sampling redress model concerning the differences between the current error rates and normalize error rates of neighboring completion matrices.The experiments show that the approach can collect the real-time sensory data,meanwhile,maintain a relatively low error rate for a small sampling rate.

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

Based on the preliminary analysis results of the indeterminate event stream that generated by the sensors and control purpose equipment of CPS,the adaptive dynamic Bayesian network and parallel Markov decision process model were used to support the proactive complex event processing.In order to resolve the vast state space issue of Markov decision process for large CPS,states partition and reward decomposition methods were proposed to parallel the decision making process.The experimental result based on the simulation of traffic network shows that proposed method can process event stream effectively and has favorable scalability.

In order to propose a more accurate forecast methods suitable for the reference crop evapotranspiration of rice in Jiangxi Province, this paper uses the PM formula and the historical meteorological data of 26 meteorological stations to calculate ET0, and uses this as a reference value to calibrate the Hargreaves-Samani (HS) model, the Blaney-Criddle (BC) model and the McCloud(MC) model. Weather forecast data is used to evaluate the applicability of the three ET0 forecast models at various stations in Jiangxi Province. The results show that after parameter calibration, the average accuracy rates of ET0 forecasts of HS model, BC model and MC model at 26 stations are 86.63%, 85.81%, 87.12%, and the average absolute errors are 0.75, 0.80 and 0.76 mm/d, the average root mean square errors are 0.98, 1.00, 0.99 mm/d, and the average correlation coefficients are 0.76, 0.76, 0.78, respectively. 16 stations recommend using the HS model for ET0 forecasting for the stations in Jiangxi Province, the HS model has the best forecast accuracy, followed by the MC model, and the BC model is the worst. On the whole, using the calibrated HS model for forecasting can provide more accurate ET0 forecasting data for irrigation forecasting and decision-making in Jiangxi Province. [ABSTRACT FROM AUTHOR]

Taking super hybrid rice variety 'Wufengyou T025' as test material, the effects of different irrigation methods and water layer depth on physiological characteristics and yield in double-season late rice under low temperature conditions during heading and flowering stage were investigated. Three treatments were set, i.e., draining during day and containing 4-5 cm water layer during night (H 1 ), draining during day and containing 8-10 cm water layer during night (H 2 ), and containing 8-10 cm water layer day and night (H 3 ), with the 0-1 cm water layer day and night was as the control (CK). The results showed that rice leaf temperature, soil layer temperature and canopy temperature under the different irrigation treatments were higher than that of CK, and the warming effect of treatment H 2 was the best during the low temperature period. Leaf chlorophyll content, net photosynthetic rate, transpiration rate, leaf stomatal conductance and intercellular CO 2 concentration of rice plants decreased gradually under the low temperature, while the smallest reduction occurred in H 2 . The increase ranges of malondialdehyde and proline content in H 2 were lower, while its soluble protein content was the highest compared with other irrigation treatments. The increase ranges for the activities of superoxide dismutase and peroxidase in H 2 were lower, while its decrease range for the activity of catalase was the lowest. Irrigation for heat preservation could increase the yield, and H 2 performed best. Yield of H 2 at the second sowing date in 2014 and 2015 encountering low temperature increased by 12.9% and 13.5% respectively compared to CK. The yield components including the effective panicle numbers per plant, panicle length, seed setting rate and 1000-grain mass were improved in all irrigation treatments compared to CK. Draining during day and containing 8-10 cm water layer during night (H 2 ) was the most effective agronomic measure to enhance the tolerance to low temperature during heading and flowering stage for double-season hybrid late rice.

Super hybrid early rice variety Ganxin 203 was used as test material, and four foliar spraying treatments were set using clear water as the control group (CK), and 3 concentrations of potassium dihydrogen phosphate (KH 2 PO 4 ) with 0.1% (P1), 0.3% (P3), 0.5% (P5) and po-tash (MH). The effects of spraying P and K fertilizers on the leaf temperature, yield and physiolo-gical characteristics in double-season early rice under low temperature conditions during panicle primordium differentiation stage were studied. The results showed that during the low temperature period 6:00-18:00, rice leaf temperature under the different treatments with potassium dihydrogen phosphate and potash was higher than that of CK. Leaf chlorophyll content and net photosynthetic rate (P n ) of rice plants decreased gradually with the treatments under low temperature, while the reduction range was the smallest in treatment P3. The activities of the antioxidative enzymes varied to different extents, and the increase range for the activities of superoxide dismutase (SOD) and peroxidase (POD) in treatment P3 were higher than those in the other treatments. The decrease range of the activity catalase (CAT) in treatment P3 was lower than that in the other treatments. At the end of low temperature treatment, malondialdehyde (MDA) content was the highest in CK. Under low temperature, foliar spraying of potassium dihydrogen phosphate or potash could improve dry matter accumulation to varying degrees and achieve the purpose of slowing down the yield decrease, among which treatment P3 was the best. It could be found from the yield components that the total grains per panicle, seed setting rate and 1000-grain mass were significantly improved for all treatments compared to CK. The application of foliar spraying of 0.3% potassium dihydrogen phosphate was the most effective agronomic measure to enhance the resistance to low temperature during panicle primordium differentiation stage for double-season super hybrid early rice.