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Network design optimization of fuel cell systems and distributed energy devices

Colella, Whitney G.

This research explores the thermodynamics, economics, and environmental impacts of innovative, stationary, polygenerative fuel cell systems (FCSs). Each main report section is split into four subsections. The first subsection, 'Potential Greenhouse Gas (GHG) Impact of Stationary FCSs,' quantifies the degree to which GHG emissions can be reduced at a U.S. regional level with the implementation of different FCS designs. The second subsection, 'Optimizing the Design of Combined Heat and Power (CHP) FCSs,' discusses energy network optimization models that evaluate novel strategies for operating CHP FCSs so as to minimize (1) electricity and heating costs for building owners and (2) emissions of the primary GHG - carbon dioxide (CO{sub 2}). The third subsection, 'Optimizing the Design of Combined Cooling, Heating, and Electric Power (CCHP) FCSs,' is similar to the second subsection but is expanded to include capturing FCS heat with absorptive cooling cycles to produce cooling energy. The fourth subsection, - Thermodynamic and Chemical Engineering Models of CCHP FCSs,' discusses the physics and thermodynamic limits of CCHP FCSs.

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Potential uses of a wireless network in physical security systems

Witzke, Edward L.

Many possible applications requiring or benefiting from a wireless network are available for bolstering physical security and awareness at high security installations or facilities. These enhancements are not always straightforward and may require careful analysis, selection, tuning, and implementation of wireless technologies. In this paper, an introduction to wireless networks and the task of enhancing physical security is first given. Next, numerous applications of a wireless network are brought forth. The technical issues that arise when using a wireless network to support these applications are then discussed. Finally, a summary is presented.

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Dielectric and ferroelectric analysis of nanoparticle/nanocrystalline barium titanate and PLZT

Diantonio, Christopher; Monson, Todd; Yang, Pin; Winter, Michael R.; Roesler, Alexander; Chavez, Thomas P.

Attractive for numerous technological applications, ferroelectronic oxides constitute an important class of multifunctional compounds. Intense experimental efforts have been made recently in synthesizing, processing and understanding ferroelectric nanostructures. This work will present the systematic characterization and optimization of barium titanate and lead lanthanum zirconate titanate nanoparticle based ceramics. The nanoparticles have been synthesized using several solution and pH-based synthesis processing routes and employed to fabricate polycrystalline ceramic and nanocomposite based components. The dielectric and ferroelectric properties of these various components have been gauged by impedance analysis and electromechanical response and will be discussed.

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A microsystems enabled field desorption source

Resnick, Paul; Hertz, Kristin

Technologies that have been developed for microelectromechanical systems (MEMS) have been applied to the fabrication of field desorption arrays. These techniques include the use of thick films for enhanced dielectric stand-off, as well as an integrated gate electrode. The increased complexity of MEMS fabrication provides enhanced design flexibility over traditional methods.

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Nano-crystalline PLZT for dielectric applications

Diantonio, Christopher; Monson, Todd; Roesler, Alexander; Huber, Dale L.; Chavez, Thomas P.; Stevens, Tyler E.

Nano-materials have shown unique crystallite-dependent properties that present distinct advantages for dielectric applications. PLZT is an excellent dielectric material used in several applications and may benefit crystallite engineering; however complex systems such as PLZT require well-controlled synthesis techniques. An aqueous based synthesis route has been developed, using standard precursor chemicals and scalable techniques to produce large batch sizes. The synthesis will be briefly covered, followed by a more in-depth discussion of incorporating nanocrystalline PLZT into a working device. Initial electrical properties will be presented illustrating the potential benefits and associated difficulties of working with PLZT nano-materials.

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Results 72676–72700 of 99,299
Results 72676–72700 of 99,299