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Kinematic coupling, as an efficient form of connection, is frequently employed for the repeated assembly and accurate positioning of replaceable opto-mechanical assemblies within high-power solid-state laser systems. During the kinematic coupling process, uncertainties in the mechanical behavior within the contact region often hinder the attainment of consistent positioning precision, potentially leading to an inability to meet operational requirements. This study aims to enhance the repetitive positioning precision of kinematic couplings. A predictive model for repetitive positioning precision is established, accounting for uncertainties in contact region forces. Based on this model, an optimization design of kinematic couplings is conducted to mitigate these challenges. Initially, accounting for uncertainties in mechanical parameters within the contact region, we formulate a static analysis computational model to elucidate the probabilistic distribution of these parameters. Subsequently, employing Hertz contact theory and Holm-Archard wear theory, we quantify the elastic deformation and equivalent wear for each contact region through the calculation of normal pressures. Building upon this foundation, we establish a predictive model for repetitive positioning precision. Finally, optimization design is carried out on the friction coefficient of contact surfaces and the structural dimensions of positioning elements. The proposed optimization design is validated through experimental verification. The findings demonstrate that optimization of structural dimensions and contact surface friction coefficients resulted in enhanced repetitive positioning precision of 35.9 %, effectively ameliorating the assembly quality. This study contributes a quantifiable analytical approach to the prediction and optimization design of repetitive positioning precision in kinematic couplings. • Repetitive positioning precision is the most critical performance indicator for kinematic couplings. • Simplify the stress, deformation and wear situation in 3D space for symmetrical structures into a plane for analysis. • A new method for predicting repeated positioning precision based on the uncertainty of mechanical parameters is proposed. • The concept that there exists a critical value for the deviation error affected by the initial deviation is proposed. [ABSTRACT FROM AUTHOR]

In this paper, a novel event-triggered predictive iterative learning control (ET-PILC) method with random packet loss compensation (RPLC) mechanism is proposed for unknown nonlinear networked systems with random packet loss (RPL). First, a new RPLC mechanism is designed by utilizing both the historical and predictive data information to avoid the deterioration of control performance due to RPL. Then, a new event-triggered condition is designed based on the proposed RPLC mechanism to save communication resources and reduce computational burden. Moreover, the convergence of the modeling error and tracking control error are analyzed theoretically, and simulation results are given to demonstrate the effectiveness of the proposed method further. • A novel random packet loss compensation (RPLC) mechanism is designed by utilizing searched iterative historical data and predicted data. The proposed RPLC mechanism can avoid the use of old historical data and prevent invalid updates of control inputs. • A new event-triggered control (ETC) strategy is designed by utilizing the RPLC data, which can simultaneously incorporate historical, estimated and predicted system data into the designed event-triggered condition, to save communication resources and reduce computational burden. • Considering both RPLC and ETC strategy for the first time in the framework of PILC, we propose a novel ET-PILC with RPLC mechanism. It can not only compensate for missing data more effectively, but also guarantee the system performance and save resources. [ABSTRACT FROM AUTHOR]

In this exploratory research, we examine the effect of policy and media indicators on the creation of Chinese state-owned enterprise policies. Using a VAR model, we show that Ministry of Finance policy and People's Daily mention of small enterprises can explain, to some extent, the incidence of state-owned enterprise policies. We verify that non-government forces are less important in determining Chinese SOE policy incidence, as has been suspected by foreign observers, and that policy is indeed made through government agenda setting or consensus building. We also provide evidence to validate the theory of Leutert (2021), that SOE policy occurs in a feedback loop (it is self-reinforcing). These explanations of Chinese policy making can be applied to other government departments to further explain policy incidence. [ABSTRACT FROM AUTHOR]

• Propose a new text-based proxy SPG which can reflect the variation of political power in China. • Contributes to the existing researches of the economic consequences of political power. • Reveal the influence mechanism of political power (SPG) on the regional economic development. China's economy has shifted from a period of high-speed growth to a new era of high-quality development and urges for further deepening the reform of government, market and the self-revolution of the Communist Party of China (CPC), among which Strict Party Governance (SPG) is an essential way. Based on the reports, communiqués, resolutions, editorials of the CPC, we use text-analysis techniques to construct a SPG Index and study the relationship between SPG and China's economic development (i.e., economic growth, pollution, innovation and income gap). Empirical results show that SPG has significantly improved China's economic development, and the effect is more pronounced in regions with higher proportion of the state-owned economy and higher level of fiscal decentralization. In terms of channel analysis, we find that the government efficiency, the degree of integrity of officials, and the marketization level are important channels for SPG in affecting economic development. Further analysis shows that SPG plays a more significant role during the period of anti-corruption and areas with weaker legal protection. Results reveal that SPG is a key factor in China's economic transition and development. [ABSTRACT FROM AUTHOR]

This study proposes a novel anti-symmetric folding layup process to reduce the surface thermal distortion of carbon-fiber-reinforced polymer (CFRP) reflector. Firstly, theoretical equations regarding the influencing factors of surface thermal distortion in CFRP reflector are derived, and the concept and advantages of the anti-symmetric folding layup process are introduced. Secondly, free thermal expansion analysis considering the ply angle misalignment is conducted, showing that the novel process can reduce surface thermal distortion by 36.13 % compared to traditional process. Finally, experimental samples with different layup processes are designed and manufactured, and their surface thermal distortion is detected using shear speckle interferometry. The experimental results show that compared with the traditional symmetric layup process, the double anti-symmetric folding layup process can reduce the surface thermal distortion of CFRP reflector by 32.39 %, demonstrating significant advantages in thermal stability and strong potential for practical engineering applications. [ABSTRACT FROM AUTHOR]

In this study, an efficient coupling surfactant to ethylene glycol pretreatment (EG) and enzymatic hydrolysis of sugarcane bagasse (SCB) was proposed to enhance fermentable sugar production with lower pretreatment energy consumption and reduced enzyme loading. Under optimized conditions, 5 % Tween 80-assisted EG pretreatment of SCB achieved 80.5 % delignification while retaining cellulose (91.6 %) and hemicellulose (81.6 %) content. This led to an enhanced glucose yield of 81.3 %, compared to 65.1 % without Tween 80. The addition of Tween 80 to pretreatment modified residual lignin through etherification, reduced phenolic hydroxyl groups and enhanced hydrophilicity by 23.7 % and 9.4 %, respectively, compared to the lignin sample without Tween 80. Consequently, this modification alleviated non-productive adsorption between lignin and enzymes, improving substrate hydrolyzability. Moreover, when 4.5 % Triton-X 100 was introduced during the hydrolysis of Tween 80-assisted EG-pretreated substrates, a maximum glucose yield of 91.8 % and xylose yield of 92.6 % were achieved. Energy and enzyme cost analyses revealed a reduction of 35 % in pretreatment energy consumption and a 58.8 % decrease in enzyme costs, thanks to the synergistic action of surfactants in EG pretreatment and enzymatic hydrolysis. Overall, integrating surfactants into pretreatment and enzymatic hydrolysis holds promise for highly efficient conversion of SCB into fermentable sugars in enzyme-mediated lignocellulosic biorefineries. [Display omitted] [ABSTRACT FROM AUTHOR]