Abstract: Systems and methods for converting thermal energy, such as solar energy, from a localized thermal energy source to another form of energy or work comprise dual thermodynamic cycle systems that utilize the liquid-to-gas phase transitions of a cryogenic fluid such as liquid nitrogen and a working fluid such as sulfur hexafluoride to drive prime movers. Heat transfer between the fluids as they undergo the phase transitions is used to increase the energy in the system and its work output, and improve system efficiency.

Abstract: Systems and methods to efficiently utilize thermal energy such as solar energy, geothermal energy, waste-heat energy, bio-mass combustion energy, or other equivalent forms of energy, convert the thermal energy to another useful form of energy, such as electricity or mechanical work using a thermodynamic cycle in which a working fluid medium may be expanded in a constant pressure environment to move a storage medium comprising another fluid, slurry or mass to a higher potential energy level, from which the storage medium may be released through a generator or the like to produce another form of energy.

Abstract: An improved bowstring mounted peep sight used in archery improving archer's accuracy. The present invention preferred embodiment having a body generally horizontal within bowstring axis has through the body centrally located luminous color optic cross-pieces indexing the center of the peep sight aperture. The characteristic of the present invention optic cross-pieces fiber side lit attenuation allows the archer to easily see through the large aperture peep sight aligning forward bow sight pin on color cross-pieces sectional center aperture small highlighted index reference window. Small reference index window cross hair center provides consistent centering reference within the large aperture by proximal blur designed within Fiber Optic Peep Sight. A second characteristic is both peep sight embodiment and optic cross-piece fibers be further enhanced with florescent light collecting glow pigment, dyes or other color illuminating materials for increased viewing during less than desirable lighting conditions.