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When a manipulator captures an unknown space object, inertia parameters of endpoint payload should be timely obtained to handle possible unexpected parameter variations and monitor the system’s operating conditions. Therefore, this study aims to present an identification method for estimating the inertia parameter of the payload carried by a flexible two-link space manipulator.

The original nonlinear dynamics model of the manipulator is linearized at a selected working point. Subsequently, the system modal frequencies with and without payload are determined using the subspace identification algorithm, and the difference of these frequencies is computed. Furthermore, by adjusting the structural configuration of the manipulator, multiple sets of frequency differences are obtained. Therefore, the inertia parameters of the payload, i.e. the mass and the moment of inertia, can be derived from the frequency differences by solving a least-squares problem.

The proposed method can effectively estimate the payload parameters and has satisfactory identification accuracy.

The approach’s implementation provides a practical reference for determining inertia parameters of an unknown space target in the capture process.

The study proposes a novel method for identifying the inertia parameters of the payload of a flexible two-link space manipulator using the estimated system frequencies.

The purpose of this paper is to analyze a new, whole‐spacecraft isolator and its performance of vibration isolation, which has been designed to ensure spacecraft safety at the launching stage.

The design is based on the analysis of fractional derivative stress‐strain constitutive relationship of viscoelastic materials. First, the authors study the constitutive relationships for viscoelastic solid of the damping materials, then the authors introduce the results obtained to the equations of motion for the damped isolator.

By performing a series of transformation, the authors obtain the analytical solution of the equations. It is shown that the results compare favourably to the numerical simulations and experiments. In addition, a saturation phenomenon for the first order damping ratio is also discussed.

It is found that the constitutive relationships written in terms of the fractional calculus can be applied in the system function of the whole‐spacecraft vibration isolator. Such relationships, developed previously from a model analysis base, have been shown to be useful tools for engineering analyses.

Some suggestions are given to improve the design of viscoelastic whole‐spacecraft isolators. The establishment of a theoretical basis for the new fractional differential dynamical system enhances their value, as they may now be used with increased reliability of satellite.

The purpose of this paper is to solve the problem of weak low-frequency vibration measurement capability of FBG accelerometer, and propose a FBG accelerometer based on cross reed.

This study proposed a new type FBG acceleration sensor based on cross reeds. When the sensor vibrates, the mass block in the new structure rotates around the center of the cross reeds, which could eliminate the impact of friction, reduce the natural frequency of the sensor and improve its sensitivity. This study theoretically analyzed the impact of several structural parameters on the sensitivity and natural frequency of the proposed sensor and used COMSOL to perform static stress analysis and modal simulation; in this study, a test system was built to test the performance of the proposed sensor.

The test results revealed that the proposed sensor had a natural frequency of 94 Hz; within a low-frequency range of 1–65 Hz, its sensitivity response was flat, the dynamic range was 81.89 dB, the sensitivity was 243.59 pm/g and the linearity was 99.97%. The cross reeds effectively strengthened the structural stability, the relative standard deviation of the repeatability of the sensor was 0.89% and the transverse crosstalk in the working frequency band was −26.97 dB.

This study innovatively proposes the structure of the two symmetrical cross reeds, which can improve sensitivity by eliminating the influence of friction, and the structure of cross reeds can effectively suppress the influence of lateral crosstalk. The proposed sensor can realize real-time accurate measurement of low-frequency weak vibration signals.

Corporate governance has attracted enormous attention both in the area of law and in the area of financial economics. In comparative corporate governance studies, many people have devoted their energy to find a best corporate governance model. I argue that a functional analysis does not support the view that there is a single best corporate governance model in the world. I further use the transplantation of an English style takeover law into China to show that the importation of foreign law is not always based on careful analysis whether the imported foreign law is the best in the world. Furthermore, I use the subsequent adjustment of the transplanted English takeover law in China to show that the imported foreign law is subject to local political and economic conditions. If there is no best corporate govern model and the transplantation of foreign law into other countries with different social and political background does not achieve similar objectives, the search for a best corporate governance model is misguided. Just as tort law or constitutional law regimes may have diversified models, so do corporate governance regimes in countries with different historical, social and political backgrounds.

The COVID-19 pandemic has hit different industries and firms with widely differing degrees of severity. The authors investigate whether ownership structure (family vs non-family) might represent a differentiating factor. The article's purpose is to conduct an initial, descriptive analysis of the impact of COVID-19 on different stock and operating performance measures of listed German companies.

The authors use a sample of 299 listed companies in Germany and gathered operating as well as stock market performance data following the outbreak of COVID-19. For the purpose of this paper, the authors solely focus on static and descriptive observations thus far. The intention of this paper is to describe potential implications for more differentiated, especially multivariate causal research, on family businesses in a post-COVID world.

The results indicate that, over the last five years, stock returns of family businesses have been higher than those of non-family firms. This effect seems to have been more pronounced during the first month following the COVID-19 outbreak. When applying operating measures, the outperformance becomes even more evident. The findings therefore seem to support the hypothesis proffered in the literature that family involvement enhances the potential for resilience in such firms.

Scholars on COVID-19 crisis performance have begun to explore firm-level factors related to financial and organizational factors, industry characteristics and country-level factors. The research extends this line of inquiry by probing the importance of family involvement in ownership.