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In the field of astronomical observation, large space telescopes are key tools for deep space exploration. However, the aperture of space telescopes is limited by the ability to fabricate large monolithic mirrors or lenses and by severe restrictions on the overall volume and mass capacity of the launch vehicle. The use of robots for autonomous assembly while in orbit is a promising option for the deployment of large-aperture space telescopes. In this paper, we describe a modular robotic manipulator that offers high precision and flexibility. A space telescope ground assembly system is then designed, the key components of which are a redundant robotic manipulator and a reconfigurable telescope unit. The ground-based assembly of the space telescope is implemented through a combination of trajectory planning, visual perception, and robotic supple control techniques, validating the ability of the robotic manipulator to automatically assemble modular space telescopes. Finally, the developed robotic manipulator is used to conduct ground assembly demonstration experiments, and the modular space telescope is assembled according to the assembly task plan, accumulating technical experience for future space telescope assembly tasks in orbit. [ABSTRACT FROM AUTHOR]

The reserve of litter is expected to be reduced on the forest floors of pine plantations dually for the prevention of high risks of forest fires and with a more practical probability of reuse. Lignin and cellulose are the two key constitutive components in litter residues that account for the highest proportion of carbon but are the last to be fully decomposed. The existing trials started examining the mechanisms behind decomposing these two components in response to the combined driving forces of microclimatic factors, forest structure, and stand properties. However, the results were mostly limited to a local-scale ecosystem, and the evidence was reported to be highly scattered across varied conditions globally. Awareness about the combined effects of the driving forces behind the lignin and cellulose contents in the litter of plantations on a large scale is still scarce. In this study, a total of 60 Pinus tabuliformis Carr. plantations (40-year-old) were investigated for their litter quality, regional meteorological factors, soil properties, and stand structure in a provincial area across Liaoning, northeast China. High lignin (40%–43%) and cellulose contents (15%–20%) were found to be located mainly in stands around the biggest city of Shenyang. Rainfall was a key factor that determined the decomposition, but neither the forest structure nor soil nutrient content generated direct effects on the two litter components. The combined factors of low soil pH (~5.8) and high rainfall (~3.0 mm per day) together mainly accounted for the promotion of natural litter decomposition. [ABSTRACT FROM AUTHOR]

To solve the problems of difficult vibration sources simulation in the ground test of the on-orbit optical load, a multi-dimensional micro-vibration simulator based on the improved Gough–Stewart platform was designed, which can effectively reproduce the characteristics of wide frequency distribution and small vibration magnitude of space micro-vibration. The analytical formula was derived by using the virtual frequent principle and the Newton–Euler equation for the natural frequency of the system, and the simulator's configuration was optimized. The structure of legs was designed and optimized according to the optimal configuration parameters. Finally, the micro-vibration simulator was tested, and the test results showed that the output bandwidth of the simulator was 5–300 Hz and the maximum magnitude error was 8%, thus demonstrating the multi-dimensional micro-vibration simulation platform has the characteristics of large frequent bandwidth, high load carrying capacity, and small vibration magnitude. [ABSTRACT FROM AUTHOR]

[Objective] This study investigated the effects of two self-developed Bacillus solid inocula (B01 and B02) and their compound agent (SB012) on green waste compost to encourage the application of solid inocula. [Method] Five treatments including blank treatment without adding bacteria (CK), solid baceria B01, B02 and SB012 as well as liquid bacteria EM, which is widely regarded as the best on the market, were applied to the plant residues artificially pruned or naturally withered from Beijing Fragrant Hills Park as raw materials for composting. The solid bactericide SB012 was created by combining B01 and B02 with mass ratio of 3 : 1. After inoculation, heap temperature was measured at 12:00 once per day. The samples were collected every 7 days to determine pH, electrical conductivity (EC), germination index (Gl), humic extract, contents of humic acid and fulvic acid, ratio of humic acid to fulvic acid, and contents and relative degradation rates of lignin and cellulose in different compost treatments and the effects of B01, B02 and SB012 on composting process were evaluated. [Result] Over time, the temperature of compost under different treatments increased first and then decreased. Compared with CK, the addition of B01, B02, SB012 and EM romoted the green waste heaps to enter the high temperature stage in advance. The peak temperatures of B01 and SB012 composts reached 72.1 and 70.2 °C, both were higher than EM and CK. The EC decreased after initial increase, while the pH of the compost increased throughout all treatments. At the end of composting process, all treatments had a pH greater than 8.0 and their EC ranged from 0.76 to 1.04 mS/cm, all of which met the national standards for green waste compost products. The GI increased first and then dereased under different treatments, and the GI order of the three kinds of solid inocula at the end of composting was SB012>B01>B02, which will all higher than that of EM and CK, reaching the standard of no toxicity to plants (≥85 %). Among the five treatments, the highest relative degradation rates of lignin and cellulose were 56.85% and 79.84% in SB012 treatment, which were significantly higher than EM treatment and CK treatment. [Conclusion] The SB012 bactericide had the best promotion for cellulose and lignin components in landscaping waste compost with the advantages of excellent quality and safety. [ABSTRACT FROM AUTHOR]