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Straw return is one of the main methods for protecting black soil. Efficient and accurate straw return detection is important for the sustainability of conservation tillage. In this study, a rapid straw return detection method is proposed for large areas. An optimized Sh-DeepLabv3+ model based on the aforementioned detection method and the characteristics of straw return in Jilin Province was then used to classify plots into different straw return cover types. The model used Mobilenetv2 as the backbone network to reduce the number of model parameters, and the channel-wise feature pyramid module based on channel attention (CA-CFP) and a low-level feature fusion module (LLFF) were used to enhance the segmentation of the plot details. In addition, a composite loss function was used to solve the problem of class imbalance in the dataset. The results show that the extraction accuracy is optimal when a 2048 × 2048-pixel scale image is used as the model input. The total parameters of the improved model are 3.79 M, and the mean intersection over union (MIoU) is 96.22%, which is better than other comparative models. After conducting a calculation of the form–grade mapping relationship, the error value of the area prediction was found to be less than 8%. The results show that the proposed rapid straw return detection method based on Sh-DeepLabv3+ can provide greater support for straw return detection. [ABSTRACT FROM AUTHOR]

This study analyzed the influence of pits on the tribological properties and friction-induced vibration noise of textured tapered roller bearings under starved lubrication. Laser marking equipment was used to fabricate pits on the outer ring surface. A vertical universal friction and wear testing machine was used to measure the friction force, vibration acceleration, and noise signals of tapered roller bearings. The difference between the pit texture surface and smooth surface in terms of friction wear and vibration noise performance was studied. The results show that the friction force and wear loss of the pit-textured surfaces are markedly lower than those on the smooth surface. Compared to smooth surface bearings, the friction force and wear loss were reduced by 45.1 and 62.5%, respectively, when the diameter, depth, and area density of the pit were 200 μm, 10 μm, and 24%, respectively. The pit-textured surface exhibited good potential for vibration absorption and noise suppression. The friction force of the pit-textured tapered roller bearings is crucial for generating the vibration noise of the friction pair system. It can effectively interfere with the self-excited vibration of the tapered roller-bearing friction pair system. It thereby reduces the degree of vibration noise of the tapered roller bearings. [ABSTRACT FROM AUTHOR]

In order to make a sound joint of TC4 titanium alloy and 316 L stainless steel, Ti-Zr-Hf-Cu-Ni amorphous filler metal was used to braze the two alloys in this paper. The effects of brazing temperature on the interfacial microstructure and mechanical property were investigated. The results showed that the maximum shear strength of 205 MPa was obtained at 960 °C/10 min. The cross section of brazed joint could be divided into five distinctive reaction zones namely: 316L, diffuson layer I, weld seam center structure H, diffuson layer &, TC4. The typical interfadal rmcrostructure of the joint was phases formed around the diffusion kyer I close to 316L stainless steel substrate, whcti was the weak part of the brazed joints. Fracture analysss idcated that cracks imtiated at the diffusion layer I . [ABSTRACT FROM AUTHOR]

The microstructures and properties of TC4 titanium alloy prepared via TIG arc additive manufacturing were studied. The results show that the microstructure of the arc additive manufacturing TC4 titanium alloy is different from the as-cast characteristics of the arc additive manufacturing steel material, which has significant heat-treated characteristics. It is a basketweave structure composed of α and β phases. Analyzing the formation process, it can be found that the primary structure of the additive body is dendrites, which has obvious orientation at this time; with the action of multiple reheating in the subsequent additive process, since the low thermal conductivity of titanium, the additive body maintains a higher temperature, the dendrite composition gradually becomes uniform and transforms into anisotropic slender β crystal grains; then the temperature decreases and transforms into a two-phase basketweave structure of α and β, and the a phase is in a supersaturated state, the β-phase precipitated with nano-scale dots can be observed, the structure and performance is close to isotropic at this time, the tensile strength and the elongation after fracture at room temperature can reach up to 998 MPa and 8.7%, respectively. [ABSTRACT FROM AUTHOR]

In this paper we present an estimation algorithm for tracking the motion of a low-observable target in a gravitational field, for example, an incoming ballistic missile (BM), using angle-only measurements. The measurements, which are obtained from a single stationary sensor, are available only for a short time. Also, the low target detection probability and high false alarm density present a difficult low-observable environment. The algorithm uses the probabilistic data association (PDA) algorithm in conjunction with maximum likelihood (ML) estimation to handle the false alarms and the less-than-unity target detection probability. The Cramer-Rao lower bound (CRLB) in clutter, which quantifies the best achievable estimator accuracy for this problem in the presence of false alarms and nonunity detection probability, is also presented. The proposed estimator is shown to be efficient, that is, it meets the CRLB, even for low-observable fluctuating targets with 6 dB average signal-to-noise ratio (SNR). For a BM in free flight with 0.6 single-scan detection probability, one can achieve a track detection probability of 0.99 with a negligible probability of false track acceptance.

At present, in the research of transplanting machinery domestic and abroad, the link of pick-up plug seedlings is the bottleneck restricting the development of automatic transplanting machines. This research of test is focused on identifying whether the proposed influencing factors changes have significant impact on the soil matrix intact rate of manipulator pick-up plug seedlings. Tested influencing factors include 3 parts, i.e. soil moisture content, shape features of manipulator structures of pick-up plug seedlings and performance improvement of root system on soil matrix shear strength in the seedling stage. Among them, soil moisture content is from 35% to 65%, and water is mixed with the soil matrix to fill the matrix pore, which increases matrix compressive ability and improves the viscosity of soil inside, at the same time also affects the adhesion force between soil matrix and plug wall. Shape features of manipulator structures of pick-up plug seedlings contain finger-shaped, tongue-shaped and u-shaped, and with these 3 shapes the manipulator contacts with the soil matrix using contact type of line, plane, and closed profile line respectively. Research shows that the root system on soil matrix weaving, winding, reticular surround and twisting force between root system and matrix particles have a significant influence on soil shear strength. In this paper, the performance improvement of root system on soil matrix shear strength is tested in the seedling stage. And the soil matrix intact rate of seedlings is taken as test index. Through the test, the change rule that compression degree determines the compression quantity of pick-up plug seedlings manipulators with different structures is as follows: The force applied on soil matrix by finger-shaped manipulator is concentrated on a few lines, and there is strong pressure on the soil matrix under the same drawing force, so it has a big compression quantity and a big clamping quantity; The tongue-shaped has a large area and weak pressure on the soil matrix, so it needs a small clamping quantity; The U-shaped is also linear contact, but because its lower end is closed, which plays a role of holding up in the process of ascension, the clamping quantity is also small. At the same time, the compression quantity is reduced with the moisture content. Our test adopts the orthogonal experiment design, and chooses L9(34) orthogonal table; with the soil matrix intact rate of seedling as test index, through the analysis of variance and range, we obtain the primary and secondary influencing factors which affect pick-up plug seedlings, and also obtain the optimal level. Meanwhile, the causes are analyzed and a better environment in pick-up plug seedlings is proposed. The results of test show that the shape feature of manipulator structures of pick-up plug seedlings is the primary factor which obviously influences the effect of pick-up plug seedlings manipulator and determines the u-shaped structure is the best. For the moisture content, around 50% is the best. When the first pair of leaves of the seedlings grow up to pick-up plug seedlings, the performance improvement of root system on soil matrix shear strength in the seedling stage has little effect on soil reinforcement. The verification test is carried out, and the results show when the soil moisture content is 50%, the u-shaped manipulator of pick-up plug seedling can make the soil intact rate of seedling all above 80% and seedlings survival quickly, which proves that the selected factors' levels are reasonable. This test determines the key technical points for further study and improving the equipment of pick-up plug seedlings, so it establishes the important theoretical basis for exploring automatic transplanting for pick-up plug seedlings. [ABSTRACT FROM AUTHOR]

Aims: Mild cognitive impairment (MCI) is a common complication of type 2 diabetes mellitus (T2DM). Changes in lifestyle and dietary patterns play a crucial role in preventing both diabetes and cognitive impairment., Methods: A cross-sectional study was conducted on 899 aging participants. The Dietary Diversity Score (DDS) was used to evaluate dietary diversity. The physical activity (PA) levels were divided based on metabolic equivalents and weekly activity time. Individual PA levels were further re-scored and combined with DDS scores to obtain each participant's total score., Results: Regardless of T2DM status, individuals with MCI had lower DDS and plant-derived DDS compared to non-MCI individuals. Non-MCI subjects had higher total PA and DDS scores than MCI subjects. There were differences in the correlation between DDS or PA scores and blood glucose and MoCA scores among different groups. The subjects with high DDS levels showed a significantly decreased risk of MCI and T2DM + MCI. Those with a total PA and DDS score in Q4 showed a significantly decreased risk of MCI and T2DM + MCI compared to Q1., Conclusions: A diversified diet improved blood glucose levels and cognitive function. Elderly individuals with diverse diets and adequate PA had a reduced risk of developing T2DM and MCI.

Purpose: Bladder cancer is one of the most frequent carcinomas worldwide, the incidence of which ranks fourth in males. MiR-19a is identified as one of the key miRs associated with tumorigenesis and has been documented to act as an oncogene in various types of tumors. The aim of this study was to explore the effects of miR-19a and RhoB in bladder cancer., Methods: The expression of miR-19a was analyzed from 54 paired of bladder cancer and paracancer tissues by real-time quantitative polymerase chain reaction (RT-qPCR). Transwell assay was employed to confirm the invasion capacity in bladder cancer. Dual luciferase reporter assay was utilized to analyze the association between the expression of miR-19a and RhoB. Western blot analyses were performed to detect the relative protein expression., Results: miR-19a was clearly overexpressed in bladder cancer tissues and cells, while the expression of RhoB was lower in bladder cancer tissues and cells as compared with corresponding paracancer tissues and normal bladder cells. Also, miR-19a could promote the invasion and epithelial-mesenchymal transition (EMT) of bladder cancer cells through inhibiting the expression of RhoB. Moreover RhoB was identified as a direct target of miR-19a and the inverse relationship between them was also observed., Conclusions: This data demonstrated that miR-19a promoted the invasion and EMT through targeting RhoB. It is suggested that miR-19a/RhoB axis may show a new way for the treatment of bladder cancer.