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The carbon/carbon (C/C) composite finger seal experiment was performed on a high-speed seal tester. The purpose of this paper is to investigate the leakage and wear characteristics of C/C composite finger seal under various operating conditions.

Static, dynamic, endurance and post endurance tests were carried out. For static and performance tests, the pressure differential changed from 0.1 to 0.6 MPa and the rotor speed varied from 1,000 to 9,000 r/min. Two endurance tests were conducted for 4 h, with each mounting two finger seals. The seal leakage was monitored by mass flowmeters, and the wear depth was measured and calculated by using three-dimensional profilometer.

Results showed that the seal leakage increases with pressure differential but decreases with rotor speed. Leakage rate is lower when speed is decelerated than that with the speed stepped up. During a time history, material removal caused by wear has significant influence on leakage data causing higher leakage than the results before endurance test. Particular interest is that the uneven wear characteristic on finger foot bottom was firstly revealed, showing severe wear in foot heel area than that in foot toe.

This study could provide experimental guidance for finger seal designers. Additionally, the uneven wear characteristic of finger foot was firstly revealed, which showed the necessity of further theoretical research on finger seal wear.

The purpose of this paper is to briefly summarize and review the theories and methods of complex structures’ dynamic reliability. Complex structures are usually assembled from multiple components and subjected to time-varying loads of aerodynamic, structural, thermal and other physical fields; its reliability analysis is of great significance to ensure the safe operation of large-scale equipment such as aviation and machinery.

In this paper for the single-objective dynamic reliability analysis of complex structures, the calculation can be categorized into Monte Carlo (MC), outcrossing rate, envelope functions and extreme value methods. The series-parallel and expansion methods, multi-extremum surrogate models and decomposed-coordinated surrogate models are summarized for the multiobjective dynamic reliability analysis of complex structures.

The numerical complex compound function and turbine blisk are used as examples to illustrate the performance of single-objective and multiobjective dynamic reliability analysis methods. Then the future development direction of dynamic reliability analysis of complex structures is prospected.

The paper provides a useful reference for further theoretical research and engineering application.

This paper aims to present a novel wireless passive pressure sensor based on an aperture coupled microstrip patch antenna embedded with an air cavity for pressure measurement.

In this paper, the sensitive membrane deformed when pressure was applied on the surface of the sensor and the relative permittivity of the mixed substrate changed, resulting in a change in the center frequency of the microstrip antenna. The size of the pressure sensor is determined by theoretical calculation and software simulation. Then, the sensor is fabricated separately as three layers using printed circuit board technology and glued together at last. The pressure test of the sensor is carried out in a sealed metal tank.

The extracted resonant frequency was found to monotonically shift from 2.219 to 1.974 GHz when the pressure varied from 0 to 300 kPa, leading to an average absolute sensitivity of 0.817 MHz/kPa.

This pressure sensor proposed here is mainly to verify the feasibility of this wireless passive maneuvering structure, and when the base material of this structure is replaced with some high-temperature-resistant material, the sensor can be used to measure the pressure inside the aircraft engine.

The sensor structure proposed here can be used to test the pressure in a high-temperature environment when the base material is replaced with some high-temperature-resistant material.

Traditional skid-to-turn (STT) missile control mode is adopted mostly, but with the improvement of requirements for mobility and the emergence of new aerodynamic layout, a bank-to-turn (BTT) control mode gradually shows a greater advantage. However, the BTT missile also has certain defects, for example, when attacking against a maneuvering target and at the last section of guidance, the maximum lifting surface position of the missile needs to be adjusted frequently, thereby increasing the difficulty of control as well as introducing high-frequency noise.

Based on respective characteristics of the two control modes, this paper puts forward a hybrid autopilot design method based on nonlinear dynamic inversion. Firstly, the method converts overload instructions into corresponding angle instructions through the design of hybrid control guidance logic; secondly, based on the nonlinear dynamic inversion algorithm and combined with the fast-changing circuit/slowly changing circuit, a hybrid controller is designed; finally, combined with the missile mathematical model and actuator, it forms a autopilot design closed loop.

The simulation result shows that the non-linear dynamic inverse-based BTT/STT hybrid controller can input a track command well, normal overload and roll angle tracking performance have more advantages than the hybrid controller designed on the basis of classical control method in terms of overshooting and hysteretic characteristics.

The paper puts forward a new BTT/STT hybrid control method which has both the high mobile ability of the BTT missile and the precise control ability of the STT missile, which can adapt to the more complicated fighting environment. And, the method can effectively weaken the impact of the transformation of the control mode on the system.

Although female participation in the labour market has increased significantly over the last 50 years, transport remains a male dominated sector and maritime transport in particular appears to lag behind other modes. It is important to recognise that maritime careers struggle to recruit more generally. This chapter considers the gender gap in the maritime industry and asks what would make the maritime industry more attractive to women. It explores the literature through the lenses of career-decision, career decidedness and career self-efficacy in order to present a conceptual model to explain the persistent gap and consider what could be done to address it. Career choices, development and performance are affected by contextual variables, both personal and environmental, which can promote or hinder career development outcomes. In maritime transport, career perception, workplace culture, social capital and development opportunities still play a major part in the decision-making process and deter women from engaging with the maritime profession. This chapter proposes four interventions to effect much-needed change.

The purpose of this paper is to elucidate the influences of the animal fat and fatty acid type on the formation of polycyclic aromatic hydrocarbons (PAHs) and to propose a formation mechanism of PAHs in fat during electric roasting, which is a method of non-direct-contact-flame heating.

The effects of animal fats and model fat on the formation of PAHs were valued on the basis of the ultra high-performance liquid chromatography data. The corresponding products of the FAME pyrolysis were detected by TG-FTIR. The proposal formation mechanism of PAHs was based on the summary of the literature.

Contrary to the International Agency for Research on Cancer, DF had higher risk with 280.53 ng/g of concentration after being roasted than the others animal fats of red meat in terms of PAHs formation. This research also ensured the importance of fat on PAHs formation, the concentration of PAHs in pure fats was higher after being electric roasted than that in meat patties and juice which made from corresponding animal fat. What is more, during pure animal fats and meat products being processed, less PAHs formed in the fat with lower extent of unsaturation and lower content of linolenate. In the same way, methyl linolenate demonstrated the significant increasement to PAHs formation compared to the other fatty acids. And, the number of carbon atom and the extent of unsaturation in fatty acid affects the formation of PAHs during roasting. The detection of alkene and alkane allows to propose a formation mechanism of PAHs during model fat being heated. Further study is required to elucidate the confirm moleculars during the formation of PAHs.

This work studied the effect of the carbon atom number and the unsaturation extent of fats and model fats on the formation of PAHs. This work also assure the important of alkene and alkane on the pyrolysis of model fats. This study also researched the formation and distribution of PAHs in pure fats and meat products after being heated.

Reports a study of 1,304 Chinese brand names of ten types of products in China. These brand names are content analyzed following a linguistic approach which the authors developed from their earlier studies. The ten types of brand names are presented in three broad categories representing the three different developing stages of the consumer product industry in China: brands of traditional products (illustrated by matches and spirits), brands of traditional products with current development (illustrated by bicycles, shoes, and toothpastes), and brands of new and modern products (illustrated by cosmetics, soft drinks, washing machines, refrigerators and TV sets). The conclusion drawn from the analysis is that one of the variables in determining how linguistic principles are being applied to Chinese brand naming is the respective stages of development of such products in the context of the Chinese market economy.

To provide valuable information for scholars to grasp the current situations, hotspots and future development trends of reliability analysis area.

In this paper, recent researches on efficient reliability analysis and applications in complex engineering structures like aeroengine rotor systems are reviewd.

The recent reliability analysis advances of engineering application in aeroengine rotor system are highlighted, it is worth pointing out that the surrogate model methods hold great efficiency and accuracy advantages in the complex reliability analysis of aeroengine rotor system, since its strong computing power can effectively reduce the analysis time consumption and accelerate the development procedures of aeroengine. Moreover, considering the multi-objective, multi-disciplinary, high-dimensionality and time-varying problems are the common problems in various complex engineering fields, the surrogate model methods and its developed methods also have broad application prospects in the future.

For the strong demand for efficient reliability design technique, this review paper may help to highlights the benefits of reliability analysis methods not only in academia but also in practical engineering application like aeroengine rotor system.

This paper aims to explore the impact of green finance on the heterogeneity of enterprise green technology innovation and the underlying mechanism between them.

Using the data of China's A-share listed enterprises from 2008 to 2020 and the fixed effect model, the authors empirically explore the relationship and mechanism between green finance and green technology innovation by constructing the green finance index while considering both the quality and quantity of innovation.

The study suggests that green finance is positively related to the quality and quantity of enterprise green technology innovation, while green finance is more effective in stimulating the quality of green technology innovation than quantity. In addition, alleviating financial mismatch and improving the quality of environmental information disclosure are core mechanisms during the process of green finance facilitating green technology innovation. Furthermore, green finance exerts a more positive effect on the quality and quantity of green technology innovation with large-size enterprises, heavily polluting industries and enterprises in the eastern region.

This paper enriches the literature on green finance and green technology innovation and provides practical significance for green finance implementation.

The purpose of this paper is to handle the problem of the radial disturbance caused by rotor mass unbalance and load change in a bearingless induction motor (BIM).

The active disturbance rejection controller (ADRC) is used to replace the traditional PI controller, and a cubic interpolation method is used to fit the nonlinear function of ADRC, so as to improve the control performance. Meanwhile, a disturbance observer is applied to the suspension system, and the observed disturbance acceleration is compensated to the suspension system in the form of current; thus, the suppression of the rotor radial disturbance is realized.

The proposed method can effectively suppress the radial disturbance of the rotor, meliorate the suspension performance of the motor and enhance the anti-interference ability of the system. Besides, it has excellent dynamic and static performance.

A radial disturbance control strategy of the BIM based on improved ADRC is proposed is to suppress the radial disturbance of the rotor. The improved ADRC is to enhance the control performance of the system, and the disturbance observer is designed to observe and compensate the disturbance.