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The purpose of this paper is to verify the feasibility of lunar capture braking through three methods based on particle swarm optimization (PSO) and compare the advantages and disadvantages of the three strategies by analyzing the results of the simulation.

The paper proposes three methods to verify capture braking based on PSO. The constraints of the method are the final lunar orbit eccentricity and the height of the final orbit around the Moon. At the same time, fuel consumption is used as a performance indicator. Then, the PSO algorithm is used to optimize the track of the capture process and simulate the entire capture braking process.

The three proposed braking strategies under the framework of PSO algorithm are very effective for solving the problem of lunar capture braking. The simulation results show that the orbit in the opposite direction of the trajectory has the most serious attenuation at perilune, and it should consume the least amount of fuel in theoretical analysis. The methods based on the fixed thrust direction braking and thrust uniform rotation braking can better ensure the final perilune control accuracy and fuel consumption. As for practice, the fixed thrust direction braking method is better realized among the three strategies.

The process of lunar capture is a complicated process, involving effective coordination between multiple subsystems. In this article, the main focus is on the correctness of the algorithm, and a simplified dynamic model is adopted. At the same time, because the capture time is short, the lunar curvature can be omitted. Furthermore, to better compare the pros and cons of different braking modes, some influence factors and perturbative forces are not considered, such as the Earth’s flatness, light pressure and system noise and errors.

This paper presents three braking strategies that can satisfy all the constraints well and optimize the fuel consumption to make the lunar capture more effective. The results of comparative analysis demonstrate that the three strategies have their own superiority, and the fixed thrust direction braking is beneficial to engineering realization and has certain engineering practicability, which can also provide reference for lunar exploration orbit design.

The proposed capture braking strategies based on PSO enable effective capture of the lunar module. During the lunar exploration, the capture braking phase determines whether the mission will be successful or not, and it is essential to control fuel consumption on the premise of accuracy. The three methods in this paper can be used to provide a study reference for the optimization of lunar capture braking.

The purpose of this paper is to design free return trajectories launching at lower-latitude launch site Wenchang and landing at relatively high-latitude landing site Siziwang Banner tailored to human lunar missions for China, and in general demonstrate the feasibility of high-latitude landings with acceptable entry range.

Free return trajectories satisfying all basic constraints were generated directly by a high-fidelity model with multiple differential corrections. Suitable initial assumptions, control parameters, constraints and stopping conditions were set. Method was developed to automatically converge unlimited trajectories accurately to the same constraints, and their characteristics affected by the ephemeris were analyzed.

Launching into lower Earth inclination plus high-latitude landing with acceptable entry range requires asymmetric trajectories with high inclination Earth entry only from the south. Periodic trends of parameters at launch, injection and entry were found and analyzed. Nominal trajectory covering phases from launch to landing for China human moon flight with minimum entry range were designed.

Such trajectories can be used by China’s future manned lunar missions. Spacecraft capability and ground station distribution shall adjust accordingly.

Previous studies mainly concentrated on symmetric free returns using low-fidelity models first. This paper investigates asymmetric free returns skipping simplified gravity model approximation to simultaneously achieve high-latitude landing and acceptable entry range, and accurate automated generation of feasible trajectories daily across 19-year lunar nodal cycle within every monthly launch window without trial and error to reflect the actual effect by the ephemeris only. Others include landing accurately by controlling entry direction and range (and altitude), minimizing entry range and designing an effective scheme of differential correction for full convergence.

The present stage of development of vehicles for space exploration corresponds to some degree to that of the aeroplane in 1905. The programme of the U.S. National Aeronautics and Space Administration in the fields of space science research, applications of Earth satellites, manned exploration of space, and vehicle development are reviewed. International co‐operation in space exploration is desirable, particularly as regards exchange of information, exchanges of scientists, co‐ordination of national programmes, and institution of co‐operative programmes.

Briefly reviews previous literature by the author before presenting an original 12 step system integration protocol designed to ensure the success of companies or countries in their efforts to develop and market new products. Looks at the issues from different strategic levels such as corporate, international, military and economic. Presents 31 case studies, including the success of Japan in microchips to the failure of Xerox to sell its invention of the Alto personal computer 3 years before Apple: from the success in DNA and Superconductor research to the success of Sunbeam in inventing and marketing food processors: and from the daring invention and production of atomic energy for survival to the successes of sewing machine inventor Howe in co‐operating on patents to compete in markets. Includes 306 questions and answers in order to qualify concepts introduced.

This paper provides reviews of distributed computing initiatives and developments in systems and cybernetics. They include: brain fingerprinting, complex and systems research, cognition of animals, and innovative systems.

A general review and survey of selected research and development topics.

Illustrates the multi‐ and trans‐disciplinary nature of cybernetics and systems in order to further research and development.

The choice of topics enables researchers to be aware of current trends in their fields and gives readers an overview of a variety of important areas.

Reviews from a worldwide database of: current reports and opinions to introduce new perspectives in research and development.

Data on the behaviour of materials at high temperatures are needed to improve current designs for missile skins, rocket motors, gas turbines and nuclear applications, but it is only within the last few years that new research tools have been developed to enable materials to bs studied under such conditions in the laboratory. This paper reviews the available techniques, with emphasis placed on the range 2,000–5,000 deg. K.: furnaces (electric resistance, induction, arc, solar), high‐intensity electric arcs, flames, combustion of molten metals, shock tubes, ultra‐high‐frequency are discharges, plasma jets, thermonuclear reactions.

In this chapter, the authors offer a critical appraisal of predictions of a jobless future due do rapid technological change, as well as provide evidence on whether the rate of occupational change has been increasing. The authors critique the “task replacement” methodology that underlies the most powerful and specific predictions about the impact of technology on employment in particular occupations. There are a number of reasons why assuming a correspondence between task replacement and employment declines is not warranted. The authors also raise questions about how rapidly the development, acceptance, and diffiusion of labor-displacing technologies is likely to occur. In the empirical portion of the chapter, the authors compare the current rate of employment disruption with those observed in earlier periods. This analysis is based on an analysis of occupation data in the US covering the period 1870–2015. Using an index of dissimilarity as the metric, the authors find that the rate of occupational change from 1870 to 2015 does not provide evidence of a sharp uptick in the rate of occupational shifts in the information age. Instead, the rate of occupation shifts has been declining slowly throughout the second half of the twentieth century. Thus, the issues and results discussed here suggest that imminent massive employment displacement is not a foregone conclusion.