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The hydraulic leveling system plays an important role in the crane load-bearing platform (Referred to as CBP). In recent years, a lot of work has been done to improve the performance of the leveling system. However, all these efforts are focused on control techniques and methods, while ignoring other comprehensive improvement options. This article takes the hydraulic legs subjected to the synchronous drive system of CBP (Referred to as CBP) as the research object, a set of hydraulic synchronous leveling system used for the valve-controlled cylinder was designed, and the mathematical model of transfer function for the valve-controlled cylinder and the theoretical solutions of main parameters in hydraulic oil circuit are obtained, then establish a mechanical model suitable for the attitude position of CBP. After that, a composite leveling strategy applied to the fuzzy PID (Proportional Integral Differential) synchronous leveling system with hydraulic legs driven synchronously was proposed, and a fuzzy PID controller was mapped out independently. Meanwhile, the above-designed sync-drive system coupling synchronous leveling process suitable for the CBP legs was carried out by AMESim and MATLAB/Simulink software. In addition, the correctness and robustness of the simulation model were verified by the leveling experiment, and the validity and reliability of the previously designed oil circuit scheme was proved. The results proposed in this paper improve the hydraulic leveling accuracy and response speed to optimize the performance of the hydraulic leveling system. [ABSTRACT FROM AUTHOR]

In the present study, the isogeometric numerical solving process incorporating non-uniform rational B-splines is put to use to analyze the size-dependent thermal postbuckling behavior of porous functionally graded (FG) microplates having a central cutout with different shapes. Accordingly, the modified couple stress continuum elasticity is employed within the framework of a hybrid-type quasi-3D higher-order plate theory to take the through-thickness deformations into consideration by only four variables. On the basis of a refined power-law function together with the Touloukian scheme, the porosity-dependent as well as temperature-dependent material properties are achieved. The couple stress-based thermal postbuckling equilibrium paths are acquired corresponding to various geometrical and material parameters and different boundary conditions. It is found that the gap between thermal postbuckling equilibrium paths relevant to various patterns of the porosity dispersion is a bit higher for the couple stress-based case than the classical one. Furthermore, it is indicated that a central cutout causes to change the trend of the load-deflection response that leads to decrease the initial thermal postbuckling strength, while it enhances the microplate strength in deep thermal postbuckling region. [ABSTRACT FROM AUTHOR]

Background: Transforming growth factor-beta 1(TGF-β1) T869C (rs1800470, the same below) gene polymorphism is notably relative with the development of Diabetic Nephropathy (DN), and CC/CT genotype diabetic have higher frequency of than TT genotype diabetic. To find out individual risk factors in the two genotypes especially in susceptible genotype could provide more efficient and targeted prevention., Methods: This was a prospective cohort study. A total of 251 type 2 diabetes mellitus (T2DM) patients [53.4% male, 56(52-67) years] were enrolled in this cohort study. Multiple concerned factors were collected and the relationship of these risk factors and development of DN were evaluated by Cox regression analysis. Hazard ratios of development of DN were calculated by Kaplan-Meier curves and the Cox proportional hazards model for CC/CT genotype versus TT genotype patients., Results: TGF-β1 T869C gene polymorphism was an independent predictor of DN in T2DM patients (HR, 2.08; 95%CI, 1.18-3.66; P=0.012). Hyperlipemia (HR, 1.91; 95%CI, 1.19-3.08; P=0.007), age (HR, 0.95; 95%CI, 0.93-0.98; P=0.001) and smoking status (HR, 2.36; 95%CI, 1.07-5.21; P=0.033) were risk indictors of the development of DN in CC/CT genotype patients. HbA1c (HR, 2.8; 95%CI, 1.07-7.30; P=0.036), hypertension (HR, 7.46; 95%CI, 1.38-40.29; P=0.02), and hyperlipemia (HR, 12.33; 95%CI, 1.05-145.39; P=0.046) were risk indictors for the development of DN in TT genotype patients., Conclusion: TGF-β1 T869C gene polymorphism was an independent predictor of DN for T2DM patients and CC/CT genotype had higher susceptibility to DN. CC/CT genotype and TT genotype patients had different risk indictors of DN.