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In order to develop hardware that can be used in space, tests under those space conditions are often important to ensure the functionality in advance. Facilities that are used to recreate gravity conditions of space include space stations, satellites, parabolic flights and earthbound facilities. Drop towers are earthbound facilities, that can replicate the gravitational conditions of free falling in space by dropping objects. Those objects would not experience any measurable force due to gravity according to Einstein’s famous thought experiment. The Einstein-Elevator is one of the first active driven drop towers with an experiment carrier falling inside a gondola. A major indicator for the quality of the facility is the residual acceleration of the payload. With the Einstein-Elevators current setup vibrations of the experiment carrier cause measurable residual accelerations of higher than 10 - 3 g. To achieve the targeted 0-g-quality with a residual acceleration of less than 1 μ g (microgravity) in the Einstein-Elevator, a new experiment carrier is required that minimizes the residual acceleration for a payload. This paper describes a design of the experiment carrier for the Einstein-Elevator that is able to reach microgravity and analyzes its functionality using FEM-simulations. [ABSTRACT FROM AUTHOR]

Increasing efforts to move into space have driven the need for new facilities that are capable of simulating weightlessness and other space gravity conditions on Earth. Simulation of weightlessness/microgravity (approximately 10-6 g) is conducted in different earthbound and flightbased facilities, often with poor availability. Other conditions such as lunar or Martian gravity with their partial Earth gravity/hypogravity cannot be performed at a large scale for scientific research on Earth. For multiple Earth gravity/hypergravity, simulation centrifuges are available, but they do not allow the possibility of abrupt acceleration changes. To support this wide range of conditions, a new technique is being developed to combine all of these requirements into a single drop tower facility. Currently under construction, the Einstein-Elevator of the Hannover Institute of Technology at the Leibniz Universität Hannover is an earthbound tool created for simulating micro-, hypo-, and hypergravity research with a high repetition rate. The facility will be capable of performing 100 experiments per day (8-h work shift), each creating 4 s of microgravity. For the first time, statistics can be applied in experiments under space gravity conditions at favorable costs and short mission times. The Einstein-Elevator offers room for large experiments with a diameter up to 1.7 m and a height up to 2 m as well as weights up to 1,000 kg. To perform larger experiments under different gravitational conditions, it was necessary to develop an innovative drive and guide concept. The Einstein- Elevator will be available for general research under different gravity conditions from 2018 onward. [ABSTRACT FROM AUTHOR]

In the maturing private equity industry, investments where the private equity fund owns a minority of the equity are gaining influence. They use different instruments for value creation than classic majority investments and involve other mechanisms of decision making. Therefore, understanding value creation in minority investments on a deal level is important. We find that overall returns of minority investments are below those of majority investments. Minority investments thus appear to offer a different type of risk-return relationship to broaden diversification for both general and limited partners. [ABSTRACT FROM AUTHOR]