Changes and Features of Indian Diplomacy in the Context of the US Indo-Pacific Strategy

Wang Rui(Rui Wang),Wang Linwei(Linwei Wang) 아시아사회과학학회 2023 Jornal of Asia Social Science Vol.10 No.2

During the Trump administration (January 2017 to December 2020), the United States formulated the “Indo-Pacific Strategy” and officially established a strategic competition with China throughout the government. The strategy aimed to woo allies and partners in the Indo-Pacific region and accelerate the construction and promotion of the “Quadrilateral Security Dialogue”. India, as the “world's largest democracy”, has unresolved border issues with China, making it a key target for the United States to woo, and thus forcing India to change its foreign policy. On February 11, 2022, the Biden administration introduced a new version of the “Indo-Pacific Strategy”, which further clarified the overall framework of strategic competition with China, continued to deepen the strategic setting with the prominent features of wooing allies and confronting China, emphasized the core role of the Quad and the central position of ASEAN countries, highlighted the military deterrence of the US-UKAustralia alliance, and created an “anti-China circle” in multiple fields such as biosecurity, science and technology, economic finance, and climate change. Although India is the founding country of the Non-Aligned Movement and has long relied on “independent and autonomous” foreign policy, the current new geopolitical environment where Sino-Indian relations are at a low point due to the border issue, Russia-Ukraine conflicts continue due to NATO's eastward expansion, and the rapid development of the Quad, signifies the power balance in the Asia-Pacific and Indian Ocean regions. This also indirectly reflects the progress of India's own “Indo-Pacific Strategy” and the implementation of the US “Indo-Pacific Strategy”, thus providing a dimension for predicting the development trend of the strategic competition between China and the US.

Study on Wear Prediction of Shield Disc Cutter in Hard Rock and Its Application

Zhenyong Wang,Chenglong Liu,Yusheng Jiang,Linwei Dong,Shixian Wang 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.3

It is important to enable the prediction of disc cutter wear during shield tunnelling through hard rock because such wear is associated with project delays and increased costs. Based on a theoretical analysis of Archard’s wear mechanism and Euler’s rotation theorem, a displacement equation of rock-breaking point A on the disc cutter ring is studied, and then a new wear prediction model is established combined with the theoretical analysis of the disc cutter force and wear test. The cutter wear prediction model is verified by using the data of two cases, and the results reveal that the errors between measured and predicted values are less than 25%. The research results also show that abrasive wear is the main wear mechanism (approximately 88%). In addition, the influence of fatigue wear is very small, accounting for only approximately 2%, which can be ignored. Finally, the maximum tunneling distance of disc cutters under different installation radii and penetration is studied using the model, and the results can be used as references for optimizing shield tunneling parameters and predicting the disc cutter replacement time.

Numerical and experimental investigations on the hydrodynamic radial force of single-channel pumps

Linwei Tan,Wei-dong Shi,Desheng Zhang,Chuan Wang,Ling Zhou,Elemam Mahmoud 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.10

In order to clarify the generation mechanism and characteristics of hydrodynamic radial force in single-channel pumps, the transient flow in three single-channel pumps was analyzed by computational fluid dynamics (CFD). The three pumps had the identical impeller but with a spiral volute (model 1), a circular volute (model 2), and a torus (model 3). Experiments on pump performance were performed and high frequency pressure sensors were mounted in the spiral volute to measure pressure distribution in the volute of model 1. It indicates that the numerical results are approximately consistent with the experimental results. The radial force is mainly caused by the pressure acting on the blade. The impeller radial force in model 1 was the largest while the model 3 was the smallest, as it is not affected by rotor stator interaction, and rotor stator interaction plays a vital role in the shock load of pumps. The radial forces of different rotational speed were analyzed and indicated that Reynolds number has little influence on the radial force coefficient C F . The dominant frequency of the radial force on the impeller is the rotational frequency of impeller for all rotational speeds. Moreover, the amplitude of the radial force fluctuations increased with increasing flow rate in model 2, but the change was not obvious with the increasing of flow rate in model 3, while at lower flow rate the largest amplitude of the radial force fluctuations was presented in models 1.

Adaptive Parameter Identification for Nonlinear Sandwich Systems with Hysteresis Nonlinearity Based Guaranteed Performance

Linwei Li,Huanlong Zhang,Fengxian Wang,Xuemei Ren 제어·로봇·시스템학회 2021 International Journal of Control, Automation, and Vol.19 No.2

The paper presents an adaptive identification algorithm via data filtering and improved prescribed performance function for Sandwich systems with hysteresis nonlinearity. By developing a filter in which the filter is simple and easy to realize online and several variables, the estimation error vector can be derived. To improve the transient performance of estimator, a modified prescribed performance function is proposed to constrain the estimation error data through the usage of the predefined domain. For the constrained estimation error condition, the error transformation technique is utilized to simplify the design of the estimator thanks to that the restricted condition is transformed into unconstrained condition. To achieve the convergence of the parameter estimation and assure the predetermined property, a fresh adaptive law is developed. Moreover, the theoretical analysis indicates that the error can converge to a small region based on martingale difference theorem. According to the numerical verification and experimental results, the advantage and practicability of the invented estimator are inspected by comparing the estimators with unconstrained condition.

Energy absorption characteristics of composite tubes with different fibers and matrix under axial quasi-static and impact crushing conditions

Dayong Hu,Yongzhen Wang,Linwei Dang,Qiang Pan 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.6

The collapse characteristics and energy absorption capability of composite tubes with different fibers and matrix were studied in present article under axial quasi-static and impact crushing conditions. The sensitivity to fibers, matrix and loading conditions were thoroughly discussed for the crushing modes and energy absorption capability. Experimental results showed specimens with different matrix and fibers exhibit three typical types of crushing modes. Specimens G803/3234 and G827/3234 had better energy absorption performance than the specimens with 5224 matrix. Impact loading condition led to lower energy absorption capability as compared to quasi-static loading condition. Moreover, impact loading condition also caused the crushing mode transition from splaying mode to fragmentation mode for G803/3234 and G827/3234.

Elastic-plastic-creep response of multilayered systems under cyclic thermo-mechanical loadings

Xiaotao Zheng,Jiqiang Wang,Wei Wang,Linwei Ma,Wei Lin,Jiuyang Yu 대한기계학회 2018 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.32 No.3

The modified Ohno and Abdel-Karim nonlinear kinematic hardening model considering cyclic hardening and creep effect are developed to investigate the deformation and residual stress of multilayered systems subjected to cyclic thermal and mechanical loads. Results reveal that, if the creep behavior is considered, significant stress relaxation takes place during about the first several cycles, and the accumulated strain of multilayered systems under deformation-controlled loads finally remains constant, which leads to shakedown. Remarkable changes of the residual stress, location of neutral axis and curvature of Si-Cu beams are observed during about the first 100 cycles. Therefore, the proposed model can be used for the engineering design of multilayered systems under complex loads.

An improved critical plane-energy multiaxial fatigue life prediction model considering shear mean stress

Jie Zhou,Zhengchao Tan,Linwei CaoLingze Meng,Yuexing Wang 대한기계학회 2023 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.37 No.5

In the present research, the effects of normal mean stress acting on fatigue evolution are considered well in critical plane multiaxial models, whereas shear mean stress effects have rarely attracted attention. These models may result in nonconservative predictions under asymmetric loadings with substantial shear mean stress. Therefore, an improved critical energy model is introduced to solve multiaxial fatigue issues on the basis of the Fatemi-Socie model and the Walker model, which consider normal mean effect, shear mean stress effect, and additional hardening effect. Moreover, experimental data from GH4169, wrought Ti-6Al-4V, and TC4 are employed to validate the proposed model. Results show that the proposed model can reasonably predict fatigue life under various loadings, particularly for asymmetric loadings.