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The turbine blades of aero-engines are subjected to cyclic high-low cycle loads in actual service environments，which is a typical high-low cycle micro motion fatigue condition. The frequent occurrence of fatigue fracture in turbine blades due to fretting fatigue seriously affects the safe operation of aero-engines. In order to study the high-low cycle fretting fatigue problems of hot end component materials，this paper designs an Inconel718 tenon connection simulation component and conducts high-low cycle composite fretting fatigue tests on it. Three different load/frequency experiment conditions were designed to compare the life distribution of the simulated parts under different conditions. The results show that high/low cycle load has significant influence on fretting fatigue life. With the increase of high/low cycle load or frequency，the fretting fatigue life of joints decreases. The test results have proven that the high-low cycle fretting fatigue test of the tenon joint structure effectively reproduces the actual service condition of turbine blades. By displaying the explicit finite element analysis，the predicted crack initiation location shows less dispersion compared to the experimental results.

The proliferation of artificial intelligence models has rendered them vulnerable to a myriad of security threats. The extensive integration of deep learning models into edge devices has introduced novel security challenges. Given the analogous structural characteristics of deep neural networks, adversaries can employ decompilation tactics to extract model structural details and parameters, facilitating the reconstruction of these models. Such actions can compromise the intellectual property rights of the model and increase the risk of white-box attacks. To mitigate the capability of model decompilers to locate and identify model operators, acquire parameters, and parse network topologies, an obfuscation framework was proposed. This framework was embedded within the model compilation process to safeguard against model extraction attacks. During the frontend optimization phase of deep learning compilers, three obfuscation techniques were developed and integrated: operator obfuscation, parameter obfuscation, and network topology obfuscation. The framework introduced opaque predicates, incorporated fake control flows, and embedded redundant memory access to thwart the reverse engineering efforts of model decompilers. The experimental findings demonstrate that the obfuscation framework, named DNNobfus, significantly diminishes the accuracy of state-of-the-art model decompilation tools in identifying model operator types and network connections to 21.63% and 48.24%, respectively. Additionally, DNNobfus achieves an average time efficiency of 67.93% and an average space efficiency of 88.37%, surpassing the performance of the obfuscation tool Obfuscator-LLVM in both respects.

In order to investigate the effect of treated recycled aggregates by pre-soaking calcium hydroxide (CH) combined with CO₂ curing on the carbonation resistance of fully recycled concrete. The carbonation depth of fully recycled concrete was tested at 3, 7, 14 and 28 days using the rapid carbonation method. The experimental results show that with the recycled aggregate replacement rate rising, the carbonation resistance of fully recycled concrete gradually decreases. CH pretreatment combined with CO₂ curing effectively improves the quality of the recycled aggregate, thereby improving the carbonation resistance of fully recycled concrete. The optimum effect of CO₂ curing on fully recycled concrete is achieved with the recycled fine aggregate replacement rate of 70% and the recycled coarse aggregate replacement rate of 100%. In addition, microscopic tests were used to reveal the enhancement mechanism of CH pretreatment combined with CO₂ curing increases the carbonation resistance of fully recycled concrete. Experimental data were used to fit and model the carbonation depth of fully recycled concrete formulated before and after CO₂ curing of recycled aggregates.

【Objective】 Irrigation modulates water movement in soil and its bioavailability to crop roots. This study is to investigate the effect of different irrigation methods on water consumption and water use efficiency of soybean during its whole growth period, with an aim to help develop water-saving irrigation. 【Method】 The field experiment was conducted in 2021 in Wuwei, Gansu province. It compared four irrigation methods: drip irrigation under film mulching, drip irrigation without mulching, border irrigation with film mulching, and border irrigation without mulching. The Bowen ratio-energy balance system was used to continuously monitor the changes in microclimate, crop growth and yield, water consumption (ET) and water use efficiency (WUE). 【Result】 ①Film mulching increased net radiation (Rn) of the soybean by 6.58 W/m2, compared to no mulching; Soil temperature increased by 1.30 ℃ relative to drip irrigation. ②irrigation method and mulching affected physiological indexes of the soybean both at significant levels. Film mulching increased the leaf area index (LAI) significantly by 18.29%, compared to no mulching, while the border irrigation increased the LAI by 5.45%, compared to drip irrigation. ③Film mulching and drip irrigation reduced the ET significantly over the whole growth period, with the mulched drip irrigation having the least ET - 378.92 mm, compared to other treatments. ④Among all environmental and biological factors, Rn and LAI are correlated with ET positively and most significantly. ⑤The yield of soybean under mulched drip irrigation was 18.07%, 5.27% and 11.17% higher than that of non-mulched drip irrigation, film mulched border irrigation, and non-mulched border irrigation, respectively. Film mulching increased WUE by 25.93% compared to no mulching, and drip irrigation increased WUE by 34.62% compared to border irrigation. The mulched drip irrigation increased WUE by 31.15%, 42.86% and 70.21%, respectively, compared to non-film mulched drip irrigation, film-mulched border irrigation and non-film mulched border irrigation. 【Conclusion】 Compared to drip irrigation without film, border irrigation with film and border irrigation without film, the yield of drip irrigation under film increased by an average of 11.51%, ET decreased by 24.13%, and WUE increased by 48.07% and irrigation water use efficiency improved by 46.57%; Taking into account the water consumption, yield and water use efficiency of soybean, drip irrigation under film provided a more benefit growth environment for soybean growth and significantly reduced ET and increased yield.

North China has specific regional advantages in the overall economic and social development of China, and water resources are the most prominent factor that affects the sustainable development of this region. This study focuses on the land spatial layout of water-and-land adapted planting in North China. Based on the analysis of agricultural planting structure and water and land resource layout in the current year (2018) of North China, and considering varied population, climate, and socio-economic scenarios and water resource constraints, the study proposes a scheme for optimizing the agricultural planting layout in North China that adapts to local water and land resource conditions. We suggest that the burden on production and supply of commercial grain and other commercial agricultural products in North China should be appropriately reduced. In terms of improving the regional water resource carrying capacity, Hebei Province should alleviate its water shortage through water transfer. Shanxi Province should improve the agricultural water use efficiency through agricultural mechanization and modernization. Shandong Province and Henan Province can moderately fallow the land and improve forest and grass coverage. It is also recommended to optimize the spatial layout of agricultural planting and adjust the planting structure to adapt to water. In shallow groundwater overexploitation areas as well as Tianjin City and the southeast of Hebei Plain where deep groundwater overexploitation is severe, semi-arid land planting systems and structures that adapt to precipitation should be developed, and the specific recuperation period should be determined according to the rate of groundwater recharge.

Conventional deformation monitoring means are limited by data accuracy, monitoring range, applicable environment and other factors, which seriously restrict the early warning and forecasting of landslide and collapse disasters.The microwave remote sensing method based on differential interference technology is an advanced technology for high precision monitoring of small displacements on non-contact surfaces nowadays.The self-researched ground-based real aperture radar system was applied in the research.This paper, based on the analysis of the signal model, summarized the process of target echo data processing with strong scattering characteristics and proposed a method applicable to verify the deformation monitoring accuracy of this type of radar system.Point target stationary and displacement experiments based on triangular plate angle reflector were carried out accordingly.Through the radar echo amplitude analysis and point cloud data fitting, the pre-defined target space position was discriminated and the target displacement standard value was determined, which proved the effectiveness of the method and the 0.1mm monitoring accuracy of the system.A slope monitoring experiment was carried out in Heidaigou open-pit coal mine in Inner Mongolia which combined with some point target deformation data illustrated the good practicality of the system.

Objective To analyze the risk factors and clinical significance of delayed cerebral infarction (DCI) after intracranial aneurysm (IA) clipping. Methods A retrospective analysis was performed on the clinical data of IA patients admitted to the First Affiliated Hospital of Chongqing Medical University from January 2015 to December 2019. A total of 480 patients undergoing aneurysm clipping were included. The patients with DCI were set as the observation group (n=42), and those without as the control group (n=438). The risk factors for DCI were screened by univariate and multivariate logistic regression analysis. Results Univariate analysis showed that female (P=0.029), small aneurysms (P=0.001), intraoperative aneurysm rupture (IAR) (P=0.007) and cerebral vasospasm (P < 0.001) were risk factors for DCI after IA clipping, while smoking history (P=0.020) was a protective factor. Multivariate logistic regression analysis indicated that small aneurysms (P=0.002, OR=2.951, 95%CI: 1.478~5.893), IAR (P=0.004, OR=7.829, 95%CI: 1.924~31.854) and cerebral vasospasm (P < 0.001, OR=5.919, 95%CI: 2.887~12.134) were postoperative independent risk factors for DCI. Conclusion Proper treatment of small aneurysms, proactive prevention of IAR and treatment of cerebral vasospasm can prevent the occurrence of DCI effectively, and thereby reduce the disability rate and improve the prognosis of patients.

Objective To study the changes of cortical thickness in different brain regions in patients with acromegaly using surface-based analysis (SRA) and analyze the association of these changes with clinical findings of the patients. Methods Thirty patients with acromegaly and 30 healthy adults underwent magnetic resonance imaging (MRI) examination using a T1-weighted three-dimensional spoiled gradient recalled (3D SPGR) sequence. The MRI images were analyzed using Freesurfer software to determine the changes of cortical thickness in different brain regions of the patients relative to those in the healthy subjects, and the correlation of these changes with the clinical findings of the patients were analyzed. Results Compared with the healthy subjects, acromegalic patients had decreased cortical thickness in the right rostral middle frontal gyrus, the right caudal middle frontal gyrus, the right precentral gyrus, the right supramarginal gyrus, the right precuneus, the right parahippocampal gyrus, the right fusiform gyrus and the left olfactory cortex thickness. The cortical thickness in the right precuneus and the right parahippocampal gyrus were inversely correlated with Hamilton Depression Scale (HAMD) scores and levels of growth hormone (GH) and insulin-like growth factor 1 (IGF-1) but were not correlated with age of the patients. Conclusion The patients with acromegaly have decreased cortical thickness in multiple brain regions, possibly as a result of high levels of GH and IGF-1. The decreased cortical thickness in the right precuneus and the right parahippocampal gyrus is correlated with depression in acromegalic patients. [

The impact of the contact angle of a droplet, the included angle of a substrate and the droplet volume on the morphology and profile of the droplet is discussed, and the spreading characteristics of lead-free solder on an inverted V-shaped substrate are studied, which provides theoretical guidance and data support for a comprehensive study of the interface reaction and wetting mechanism between solder and substrate, and helps improve the brazing process to adapt to complex welding operations. Based on the method of finite element simulation, different contact angles, included angles of inverted V-shaped substrate, droplet volumes and other variables are entered in the model; the relevant physical parameters are defined according to the surface tension and density of solder Sn-3.0Ag-0.5Cu at temperature of 490K; the theoretical spreading results of the droplet are simulated and calculated by Surface Evolver by using the principle of energy minimization and the method of gradient descent; and the spreading distance, contact area and energy equivalence of the droplet are read out by program, which helps to investigate the spreading behavior and wetting characteristics of the droplet.