Deployment of Long Flexible Element on Spacecraft with Magnetic Damper

From the foregoing considerations, the energy-linked transhydrogenase reaction emerges as a powerful and flexible element in the network of redox and energy interrelationships that integrate mitochondrial and cytosolic metabolism. Its thermodynamic features make it possible for the reaction to respond readily to challenges, either on the side of NADPH utilization or on the side of energy depletion. Yet, the kinetic features are designed to prevent a wasteful input of energy when other sources of reducing equivalents to NADP are available, or to deplete the redox potential of NADPH in other than emergency conditions. By virtue of these characteristics, the energy-linked transhydrogenase can act as an effective buffer system, guarding against an excessive depletion of NADPH, preventing uncontrolled changes in key metabolites associated with NADP-dependent enzymes and calling on the supply of reducing equivalents from NAD-linked substrates only under conditions of high demand for NADPH. At the same time, it can provide an emergency protection against a depletion of energy, especially in situations of anoxia where a supply of reducing equivalents through NADP-linked substrates can be maintained. The flexibility of this design makes it possible that the functions of the energy-linked transhydrogenase vary from one tissue to another and are readily adjustable to different metabolic conditions.

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Hierarchical Indexing and Flexible Element Retrieval for Structured Document

Lecture Notes in Computer Science - Advances in Information Retrieval ◽

10.1007/3-540-36618-0_6 ◽

2003 ◽

pp. 73-87 ◽

Cited By ~ 7

Author(s):

Hang Cui ◽

Ji-Rong Wen ◽

Tat-Seng Chua

Keyword(s):

Flexible Element ◽

Structured Document

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A Simple Flexible Plate for Usage as Force Sensor Element With Constant Stiffness

Volume 4A: Dynamics, Vibration and Control ◽

10.1115/imece2013-63571 ◽

2013 ◽

Author(s):

Thomas Ottnad ◽

Henrik Lüßmann ◽

Tim C. Lueth

Keyword(s):

Pressure Sensor ◽

Pressure Sensors ◽

Force Sensor ◽

Mechanical Deformation ◽

Test Rig ◽

Working Pressure ◽

Constant Stiffness ◽

Flexible Element ◽

Electrical Actuator ◽

Different Types

Control of pressure is one of the most decisive parameters influencing the quality and reproducibility of products when dealing with plastics producing techniques such as injection molding, extrusion, and related techniques. For that purpose different types of pressure sensors for specific tasks come into action. Different tasks can be different working pressure ranges, static or dynamic pressure, working temperatures and requirements concerning the environment. Therefore different types of pressure sensors are commonly used which most often transform mechanical deformation into electrical signals and these in turn are converted into the value of pressure. This in turn can mean extensive effort for installation and insulation of the pressure sensors. An approach to design a pressure sensor based solely on its mechanical deformation is basic idea of the present work. The pressure sensor consists of a flexible element which is in fact a thin plate with a ram on its outer side and can be clamped easily at any desired area on a melt channel. When being applied to pressure the working pressure causes a deflection of the flexible element. Measuring this deflection and knowing the mechanical behavior of the flexible element allows the calculation of the value of pressure. To get to know to the mechanical behavior, especially the stiffness, of the flexible element a test rig was designed and refined. In the test rig as substitution of the pressure variable but defined load can be applied using a piezo-electrical actuator with integrated position sensor. Measuring the applied force using a force sensor and measuring the resulting deflection of the flexible element using a length gauge allows to calculate the stiffness of the flexible element. Regarding the flexible element as Kirchhoff plate a constant stiffness is expected and this could be proven taking measurements. When taking a look at the deflection of the piezo-electrical actuator and the flexible element there is a difference due to the elasticity of the test rig itself. When determining the stiffness of the test rig a non-constant stiffness was detected which was not expected. Reason for that is the non-constant stiffness of the used force sensor though stated other by the manufacturer. This could be proven substituting the force sensor with the flexible element. With that the flexible element showed to be appropriate to be used as force sensor with a constant stiffness.

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Aeroelastically adaptive propeller using blades’ root flexibility

The Aeronautical Journal ◽

10.1017/s0001924000000221 ◽

2004 ◽

Vol 108 (1086) ◽

pp. 411-418 ◽

Cited By ~ 7

Author(s):

Y. Sandak ◽

A. Rosen

Keyword(s):

Torsional Moment ◽

Flexible Element ◽

Blade Root ◽

Wide Range ◽

Low Speeds ◽

Flight Regimes ◽

Propeller Thrust ◽

Fixed Pitch

Abstract Usually a fixed pitch propeller is designed to be optimal at cruise speeds. Thus the efficiency is quite low at takeoff or low speeds, as well as during other flight regimes. The present paper shows that by introducing a flexible element into the blade root, the propeller efficiency can be improved over a wide range of velocities. The flexible element reacts to root flap or torsion moments by changing the blade pitch at the root. The root flexibility and the pitch angles at the root at zero loads are chosen such that efficiency will increase during problematic regimes without decreasing the propeller thrust. In the case of straight blades the torsional moment at the root is too small to be used. In the case of swept blades this moment component is significantly increased and can contribute to the design of an optimal aeroelastically adaptive propeller.

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