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To tackle the problem of resource competition among service migrations caused by limited edge server resources in mobile edge computing (MEC) scenarios, a service migration optimization method for resource competition based on Lyapunov and game theory (OMRC-LG) was proposed. Considering the system's limited migration costs and the difficulty of predicting trajectories when the number of users was large, the service migration was modeled as an optimization problem with migration cost constraints and used the Lyapunov technique to transform it into an online problem without user trajectory prediction. To alleviate resource competition among users, a distributed method based on game theory was proposed. By sharing user service migration decisions, the method obtained accurate information on available edge server resources and would continuously update these decisions to optimize service migration. Simulation results show that the OMRC-LG method can reduce the average service delay while satisfying the migration cost constraints.

In recent years, the demand of express industry has increased rapidly, and the express industry is under increasing pressure. The unmanned aerial vehicle (UAV) delivery has become an effective supplement to vehicle delivery due to its low human cost, flexibility and convenience. However, UAVs are often limited by factors such as endurance and load capacity, requiring a low-cost and energy self-sustaining scheduling scheme for delivery and charging to support collaborative delivery of multiple UAVs. A two-stage self-sustaining multiple UAV cooperative delivery and charging scheduling scheme was proposed. The first stage aims at finding the delivery routes of UAVs to complete all delivery tasks in the region such that the number of UAVs was minimized under the energy and load capacity constraints of UAVs. The UAV delivery scheduling algorithm (UDSA) was proposed, and the approximation of UDSA was proved theoretically. The second stage aims to schedule the charging of UAVs with different arrival times to minimize the maximum charging completion time of all UAVs. An approximate UAV delivery scheduling algorithm (UCSA) was proposed to solve the problem. The simulation results show that, compared with the benchmark algorithm, UDSA can reduce the number of UAVs by 44.17% at most, and UCSA can reduce the maximum charging completion time by 18.87% at most.

This paper proposes a strategy for synergistic improvement of physical fitness and skills of basketball players with the content of big data analysis of decision-making of physical fitness training programs and estimation of the human posture of basketball players. The data related to physical training and testing are processed using neural network methods, and a priori algorithms with continuous attributes discretize the data to realize data fragmentation and prevent data distortion caused by intrinsic correlation so as to build up a technical and methodological platform for physical training programs. At the same time, the basketball action posture estimation algorithm based on multi-scale spatiotemporal correlation features is proposed, and the human body temporal sequence feature capture module based on Transformer is constructed to improve the accuracy of basketball action posture estimation to meet the needs of skill training. The men’s basketball team of Shandong Agricultural University in China was used as a research object to carry out basketball physical fitness and skill training practices. The experimental group’s basketball players’ performance in barbell bench press and weighted squat was 11.06kg and 10.05kg more than that of the control group. Their performance in 3/4-court sprint running, and return running. Restriction-area footwork was 0.52s, 2.16s, and 1.97s faster than that of the control group, with significant differences in basketball skills, such as 14-meter round-trip straight-line dribbling around the pole and 30-second in situ spotting of two-handed chest pass (the first time in the experimental group). Basketball skills showed significant differences (P

Dioscorea cirrhosa L. (D. cirrhosa) tuber is a traditional medicinal plant that is abundant in various pharmacological substances. Although diosgenin is commonly found in many Dioscoreaceae plants, its presence in D. cirrhosa remained uncertain. To address this, HPLC-MS/MS analysis was conducted and 13 diosgenin metabolites were identified in D. cirrhosa tuber. Furthermore, we utilized transcriptome data to identify 21 key enzymes and 43 unigenes that are involved in diosgenin biosynthesis, leading to a proposed pathway for diosgenin biosynthesis in D. cirrhosa. A total of 3,365 unigenes belonging to 82 transcription factor (TF) families were annotated, including MYB, AP2/ERF, bZIP, bHLH, WRKY, NAC, C2H2, C3H, SNF2 and Aux/IAA. Correlation analysis revealed that 22 TFs are strongly associated with diosgenin biosynthesis genes (—r2— > 0.9, P

In this study, a spiral bevel gearbox of the aero-engine is taken as the research object. A method of gear system-level modal analysis of bevel gears is proposed. Based on the design parameters and machining parameters, a 3D model of spiral bevel gear pairs with accurate tooth surface is established. Then the static analysis of the gear pair is carried out to determine the normal contact of the gears. After that, the pre-stressed modal analysis is done to obtain the modal of the gear system. And the result is compared with the experimental data to verify the accuracy and effectiveness of the method. Finally, according to the engineering practice, the influence of different contact surfaces and loads on the system mode is analyzed. The results show that the pre-stressed modal analysis method based on accurate tooth surface can be used for modal analysis of the bevel gear system. The system mode has strong sensitivity to the contact surfaces but is weak to loads. That is to say, in a certain range, the influence of loads can be ignored, but the modal analysis of different contact surfaces is needed.

In order to improve the accuracy of collected data and avoid table lookup, the adaptive weighted fusion algorithm is improved. According to the characteristics of the median and the mean value in the normal distribution, a new method of preprocessing to remove outliers is proposed to improve the accuracy of the final fusion result. The algorithm is used to calculate the temperature data to be processed in a greenhouse. The results showed that the fusion result after average processing was Xˆ\hat{X} = 15.77°C. The standard deviation is σ\sigma = 0.1194°C. After the treatment of the Grabbs criterion, the fusion result is Xˆ\hat{X} = 15.73°C and the standard deviation is σ\sigma = 0.1110°C. The fusion result of the improved algorithm is Xˆ\hat{X} = 15.74°C. The standard deviation is σ\sigma = 0.0959°C. Advantages of various preprocessing algorithms: improved algorithm > Grubbs method > no preprocessing. From the processing results of group A1 data, it can be seen that the improved algorithm can effectively suppress the ipsilateral shielding effect. Compared with the traditional Grubbs method to eliminate outliers and other algorithms, the improved algorithm can make the standard deviation of the fusion result smaller, and the fusion result can better represent the overall distribution, and there is no need to look up the table.

This article gives a review on domestic and foreign researches on the non-drug intervention for patients with perimenopausal depression published from 2012 to 2022， so as to provide a reference for clinical treatment and nursing. Currently， pharmacotherapy is the mainstay of treatment for perimenopausal depression， while many existing problems remain to be solved such as the variation in treatment effect and the difficulty in maintaining emotional stability. however，high safety and relatively low cost are the characteristics of non-drug intervention， so this article expounds on the non-drug intervention measures for perimenopausal depression， such as music therapy， dietary therapy， exercise therapy， acupuncture therapy and repetitive transcranial magnetic stimulation （rTMS）.

The host-guest complex of water-soluble phosphate salt pillar[5]arene (PP5A) and cationic fluorescent dye acridine orange (AO) was constructed, and studied with ultraviolet spectrum (UV), infrared absorption spectrum (IR), molecular fluorescence spectroscopy (MFS), and nuclear magnetic resonance (NMR) spectra (1H NMR and NOESY). And then, the effect of pH and two surfactants, including sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB) on the fluorescence intensity of AO/PP5A complex system were investigated. Finally, the complexation mode and energy of PP5A with AO and CTAB were calculated by molecular docking. The results showed that AO and PP5A formed a 1:1 host-guest complex. PP5A reduced or quenched the fluorescence intensity of AO in the pH range of 3~11. The addition of SDS and CTAB did not affect the fluorescence intensity of AO/PP5A complex significantly. The fluorescence changes generated by AO and PP5A complexation can provide a theoretical basis for the design of fluorescence sensors.

Conventional Li-ion battery intercalation cathodes leverage charge compensation that is formally associated with redox on the transition metal. Employing the anions in the charge compensation mechanism, so-called anion redox, can yield higher capacities beyond the traditional limitations of intercalation chemistry. Here, we aim to understand the structural considerations that enable anion oxidation and focus on processes that result in structural changes, such as the formation of persulfide bonds. Using a Li-rich metal sulfide as a model system, we present both first-principles simulations and experimental data that show that cation vacancies are required for anion oxidation. First-principles simulations show that the oxidation of sulfide to persulfide only occurs when a neighboring vacancy is present. To experimentally probe the role of vacancies in anion redox processes, we introduce vacancies into the Li2TiS3 phase while maintaining a high valency of Ti. When the cation sublattice is fully occupied and no vacancies can be formed through transition metal oxidation, the material is electrochemically inert. Upon introduction of vacancies, the material can support high degrees of anion redox, even in the absence of transition metal oxidation. The model system offers fundamental insights to deepen our understanding of structure-property relationships that govern reversible anion redox in sulfides and demonstrates that cation vacancies are required for anion oxidation, in which persulfides are formed.

The propeller blades used in unmanned multi-rotor aircraft are mainly fixed-wing propellers, but their aerodynamic environments are not the same. The parametric modeling of the original blades is established by using the inverse reconfiguration technique and based on CFD technology the design of the parametric reference model’s torsional angle distribution and the leaf-type stacking pattern in the vertical flight state is optimized. The results show that the efficiency of the blade in the hovering state is greatly improved within the power allowable range.

Addressing sustainable energy storage remains crucial for transitioning to renewable sources. While Li-ion batteries have made significant contributions, enhancing their capacity through alternative materials remains a key challenge. Micro-crystalline silicon is a promising anode material due to its tenfold higher theoretical capacity compared to conventional graphite. However, its substantial volumetric expansion during cycling impedes practical application due to mechanical failure and rapid capacity fading. We propose a novel approach to mitigate this issue by incorporating trace amounts of aluminum into the micro-crystalline silicon electrode using ball milling. We employ density functional theory (DFT) to establish a theoretical framework elucidating how grain boundary sliding, a key mechanism involved in preventing mechanical failure, is facilitated by the presence of trace aluminum at grain boundaries. This, in turn, reduces stress accumulation within the material, reducing the likelihood of failure. To validate our theoretical predictions, we conducted capacity retention experiments on undoped and Al-doped micro-crystalline silicon samples. The results demonstrate significantly reduced capacity fading in the doped sample, corroborating the theoretical framework and showcasing the potential of aluminum doping for improved Li-ion battery performance.

Soil salinization is among the most critical threats to agriculture and food security. Excess of salts adversely affects soil structure and fertility, plant growth, crop yield, and microorganisms. It is caused by natural processes, such as dry climates and low precipitations, high evaporation rate, poor waterlogging, and human factors, such as inappropriate irrigation practices, poor drainage systems, and excessive use of fertilizers. The growing extremization of climate with prolonged drought conditions is worsening the phenomenon. Nature-based solutions (NBS), combined with precision or conservation agriculture, represent a sustainable response, and offer benefits through revitalizing ecosystem services. This perspective explores NBS that can be adopted, along with their challenges and implementation limitations. We also argue that NBS could not be enough to combat hunger in the worlds most vulnerable regions and fully achieve the Sustainable Development Goal - Zero Hunger (SDG2). We therefore discuss their possible combination with salt-tolerant crops based on bioengineering.

(Fe0.52Co0.30Ni0.18)73Cr17Zr10 amorphous ribbons were prepared by melt-spun method and annealed at different temperatures. X-ray diffraction, atomic force microscopy and vibrating sample magnetometer were adopted to study the effect of annealing temperature on the microstructure and magnetic properties of this alloy.The results show that the crystallization process of this alloy is amorphous→α-Fe(Co)+amorphous'→α-Fe(Co)+Cr2Ni3+Fe3Ni2+Cr2Zr+ unidentified phase. When annealing temperature Ti is lower than Tg, the Ms increases slightly as a result of relaxation of the internal stress of the as-quenched amorphous alloy. When Ti is in between Tx and Tp1, the Ms significantly increases due to the partial crystallization of amorphous precursors to create a homogeneous distribution of α-Fe(Co) nanocrystals within a residual amorphous matrix. When Ti is higher than Tp1, the Ms drops rapidly, which may be caused by the grain growth and the formation of paramagnetic phase. This alloy after annealed at 565℃ has the best magnetic property(Ms=106.8A·m2·kg-1). The results of AFM observation show that in the annealed amorphous ribbons the grain size measured from AFM graphs is much larger than that of the α-Fe(Co) nanocrystal size caculated by Scherrer method, which is a typical phenomenon of coated grain.

In traditional plane near-field acoustic holography reconstruction process,regardless of wave number domain filter or regularization method,they cannot solve their own ill-posed problem,and thus cannot improve the reconstruction accuracy. Plane near-field acoustic holography based on Compressive Sampling,translates traditional solved particle velocity into solving sparse coefficient,by effective using of the particle velocity sparsity,avoiding the reconstruction process of ill-posed problem. Combined with plane near-field acoustic holography based on Tikhonov regularization method, we analyze the reconstruction accuracy of numerical simulation. The results show that, plane near-field acoustic holography based on Compressive Sampling has a good accuracy in reconstruction process,especially in the border region of reconstructive surface.Finally,this method can effectively identify the source of the noise of the refrigerator,to provide an effective basis for noise control.

In view of problems of low accuracy and inadequate decision support existed in analysis and control of production cost of coal enterprises, the paper proposed a design scheme of production cost management and decision support. The scheme uses data market to collect the production cost in whole production range and make real-time collection and assignment for the production cost, and it uses technologies of online analytical processing and data mining to get law and trend hided in internal of the production cost, so as to provide decision support for decision-maker. The actual application shows that the scheme realizes real-time analysis and control for the production cost.

The southern coal mines are characterized by wide distribution, a large quantity, small-sized single coal mine and complicated surroundings with the management mode of three layers structure of company-mine-underground. For these characteristics, an integrated automation system which is suitable for southern coal mines was developed. The technology system structure, system functions and integration technology of software development of the system were introduced. The system uses OPC interface technology to solve problems of interconnection and access between hardware devices, and adopts XML middleware to solve problems of accessing to data information and unifying interfaces in the heterogeneous databases. The actual application shows that the system improves production efficiency, reduces potential safety hazard, and saves cost of production.

The paper analyzed main features of power supply system of industrial and mining enterprises and its problems existed in safety operation, gave key technologies such as particular load modeling, power supply system modeling, location and management of forced power oscillation, security and stability analysis and control strategy of the power supply system as well as integrated platform design, and put forward project implementation scheme and flow. The key technologies and scheme are helpful for improving control precision level and safety operation of power supply system of industrial and mining enterprises.

In order to solve the problems of existing physical simulation experiment device for thermal recovery, such as great heat loss, low precision in internal pressure control of physical model and insufficient process monitoring, a new experiment device for high-pressure and high-temperature (HPHT) 3D scaled physical simulation is developed independently, and the relevant experiment technical route is presented. By using thermal fluid simulation, PID auto-control and 3D graphics, the following problems are solved: (1) the heat loss scaled simulation technology is applied for HPHT thermal recovery model, to control the heat dissipating capacity of the model top and bottom and realize the continuous growth of the steam chamber; (2) HPHT 3D formation temperature/pressure simulation technology is applied to keep the model pressure and temperature stable, ensuring temperature difference at each point in high-pressure chamber less than ± 2 °C; (3) 3D data field on-line monitoring and visual analysis technology is applied to monitor and control the reservoir performance at real time. By using this experiment device, 3D scaled physical simulation experiment is performed for commingled thermal recovery of extremely heavy oil by horizontal/vertical wells as well as SAGD of super heavy oil by dual horizontal wells. The evolution of steam chamber is depicted and the knowledge on SAGD mechanism by dual horizontal wells and the production performance is deeply studied. 摘要: 为了解决现有热采物理模拟装置模型热损失大、模型内压控制精度低、实验过程监控不足等问题 自主研制成功了新型高温高压三维比例物理模拟实验装置并提出了注蒸汽采油高温高压三维比例物理模拟实验技术路线。该装置采用热流数值模拟、PID自动控制及三维数据场平面设计方法 重点解决了以下难题并形成特色技术°采用高温高压热采模型热损失比例模化技术 比例控制模型顶底散热量 实现汽腔持续发育 °采用高温高压三维地层温/压模拟技术 实现模型压力均匀稳定控制 高压舱内各点温差小于±2 ࠓ °采用模型三维数据场在线监测与可视化分析技术 实时监测与调控油藏动态。利用该实验装置开展了特稠油水平井与直井组合热采及超稠油双水平井SAGD 蒸汽辅助重力泄油三维比例物理模拟实验研究 完整刻画了汽腔发育规律 深化了对双水平井SAGD开采机理和生产动态规律的认识。图5参13 关键词注蒸汽采油 比例物理模拟 三维模型 高温高压 蒸汽辅助重力泄油-图分类号TE345 文献标识码A Key words: steam injection recovery, scaled physical simulation, 3D physical model, high-pressure and high-temperature, steam assisted gravity drainage (SAGD)