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Mechanical Engineering. 2006;128(05):27-31. doi:10.1115/1.2006-May-1.
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This paper describes the vision for Space Exploration that would return humans to the moon by 2020. Creating architecture for returning humans to the moon requires the comprehension of the physics of spaceflight, knowledge of the hardware that can realize the physics, and an understanding of how these many parts interact and interconnect. The NASA team concluded early in its study that the direct–direct mode would be possible only if a single launch vehicle approaching twice the lift capacity of the Saturn V were available. The three mission modes were compared as higher levels of technology were engaged. The key was to find a workable architecture that involved the least amount of mass. The direct return mission that involved no operations in lunar orbit seems to be the least operationally complex, but it tends to be the least efficient because it moves the largest mass-including the Earth-entry heat shield- the entire velocity change of lunar landing and ascent.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2006;128(05):32-35. doi:10.1115/1.2006-MAY-2.
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This article discusses the promotion of Global Nuclear Energy Partnership (GNEP) by US Department of Energy. GNEP is a strategy for dealing with the accumulation of radioactive waste from power plants by reprocessing some of the spent fuel. The primary domestic benefit of this initiative would be to reduce the quantity of plutonium and other transuranic waste that would have to be buried in Yucca Mountain, the Nevada site identified as the national depository for nuclear waste. The objective of GNEP is to fission all of the transuranics, aside from process losses. The National Academy of Sciences (NAS) study scaled its cost estimate to 62,000 tons of spent fuel because that is approximately the amount of spent fuel that the Nuclear Waste Policy Act allows to be placed in Yucca Mountain before a second repository in another state is in operation. The huge cost of the GNEP would likely be more of a burden than a help to the future of nuclear power in the United States.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2006;128(05):36-39. doi:10.1115/1.2006-MAY-3.
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This paper focuses on research and innovation in the gas turbine industry. The production of nonaviation gas turbines was $3.6 billion in 1990, only 15% of total production. With improvement in thermal efficiency, increases in unit size, and the building of record breaking combined-cycle electric power plants fueled by cheap natural gas, nonaviation production zoomed to a euphoric high of $25.8 billion in 2001. The US Department of Energy announced last year the award of $130 million for 10 new projects to integrate hydrogen-burning gas turbines and turbine subsystems into integrated gasification combined cycle (IGCC) central power stations. Nuclear generation is also a zero-emissions technology, and Pebble Bed Modular Reactor Ltd, a South African company, is developing a gas turbine-nuclear reactor electric power plant, with participating companies that include Westinghouse, MHI of Japan, Nukem of Germany, and South Africa's Eskom.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2006;128(05):40-43. doi:10.1115/1.2006-MAY-4.
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This paper discusses the development of high-temperature fuel cells for stationary industrial and residential power generation applications. The system can operate on hydrogen, extracted by an internal reformer, and on a fuel comprising carbon monoxide. The technology enables fuel flexibility and, in addition, the high temperature provides high-quality co-generation of a thermal product and an ultimate overall efficiency exceeding 80%. Alone, high-temperature fuel cells show tremendous promise. Through hybridization, however, high-temperature fuel cells have a novel capability to achieve a quantum jump in fuel-to-electricity efficiency. In a hybrid configuration, high-temperature fuel cell technology promises new means to provide hoteling or propulsive power for ships, locomotives, long-distance trucks, and civil aircraft.

Commentary by Dr. Valentin Fuster
Mechanical Engineering. 2006;128(05):46-48. doi:10.1115/1.2006-MAY-5.
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This paper highlights the design of finite element analysis (FEA) without the finite element. The analysis can use the same information, the CAD system used to create the geometry in the first place. The geometry as well as the analysis fields-like displacement or temperature all uses the non-uniform rational B-spline mathematical representation. Software makers generally use the NURBS mathematical model to generate curves and surfaces in a digitized image. The framework lets mechanical engineers run quick, what-if scenarios to determine how changing a piece of a subassembly would affect the entire assembly. The full assembly need not be remeshed.

Commentary by Dr. Valentin Fuster

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