3,879 research outputs found
On the physical association of the peculiar emission: Line stars HD 122669 and HD 122691
Spectroscopic and photometric observations indicate a physical association between the peculiar early-type emission-line stars HD 122669 and HD 122691. The latter has undergone a drastic change in the strength of its emission lines during the past twenty years. There is some indication that both stars vary with shorter time scales
Partial breakdown of quantum thermalization in a Hubbard-like model
We study the possible breakdown of quantum thermalization in a model of
itinerant electrons on a one-dimensional chain without disorder, with both spin
and charge degrees of freedom. The eigenstates of this model exhibit peculiar
properties in the entanglement entropy, the apparent scaling of which is
modified from a "volume law" to an "area law" after performing a partial,
site-wise measurement on the system. These properties and others suggest that
this model realizes a new, non-thermal phase of matter, known as a quantum
disentangled liquid (QDL). The putative existence of this phase has striking
implications for the foundations of quantum statistical mechanics.Comment: As accepted to PR
Quasi-steady MPD propulsion at high power Final technical report
Quasi-steady MPD propulsion at power levels in range 1 to 10 megawatt
Study of instabilities in linear Hall current accelerators
Ion and electron conservation equations used in analysis of instability of linear Hall current accelerato
Riccati parameter modes from Newtonian free damping motion by supersymmetry
We determine the class of damped modes \tilde{y} which are related to the
common free damping modes y by supersymmetry. They are obtained by employing
the factorization of Newton's differential equation of motion for the free
damped oscillator by means of the general solution of the corresponding Riccati
equation together with Witten's method of constructing the supersymmetric
partner operator. This procedure leads to one-parameter families of (transient)
modes for each of the three types of free damping, corresponding to a
particular type of %time-dependent angular frequency. %time-dependent,
antirestoring acceleration (adding up to the usual Hooke restoring
acceleration) of the form a(t)=\frac{2\gamma ^2}{(\gamma t+1)^{2}}\tilde{y},
where \gamma is the family parameter that has been chosen as the inverse of the
Riccati integration constant. In supersymmetric terms, they represent all those
one Riccati parameter damping modes having the same Newtonian free damping
partner modeComment: 6 pages, twocolumn, 6 figures, only first 3 publishe
Suppression of combustion oscillations with mechanical devices Interim report
Static rocket thrust chamber simulator for cylindrical cold flow-type apparatus desig
The BLOOMhouse:Zero Net Energy Housing
The 2007 University of Texas Solar Decathlon House is called the BLOOMhouse because it represents the “seed” of new ideas for zero net energy housing. The University of Texas student team developed a prefabricated 7.9 kW stand-alone solar-powered modular house that sits lightly on the land and forms the superstructure for photovoltaic technologies and a sustainable approach to the building envelope. The prefabricated house can be adapted to a specific site and modified for the needs of a different site within a different climatic zone, and client context. Recognizing that consumers look to Solar Decathlon entries for ideas of how to integrate renewable energy technologies into their own homes this house will serve as a working example to homeowners, homebuilders, and architects.
The Solar Decathlon is an international initiative and University competition sponsored by the U.S. Department of Energy, designed to stimulate research, industry and education to advance renewable energy technologies, with a specific focus on building-integrated photovoltaics. Now entering its fourth cycle, the Decathlon provides a unique opportunity to envision, fabricate and test the possibilities of highly efficient modern dwellings. Our team of architecture and engineering faculty and students under the direction of Professor Michael Garrison, Professor Samantha Randall, Professor Atila Novoselac, and Lecturer Russell Krepart constructed a completely stand-alone solar-powered home that serves as a catalyst for change, leading the residential housing industry toward more sustainable practices while addressing the need for well designed, appropriately diverse, economically viable, and environmentally responsible housing. Through use of solar power and energy efficient design, this project offers homeowners the means to directly participate in the energy economy, moving from energy consumers to energy
producers.
The Solar Decathlon completion occurs every two years and is run by the National Renewable Energy Laboratory, which requires a portable structure of a fairly modest scale, with a dual prescription for both exhibition and inhabitation. The Program calls for the design to appeal to the normal modern American lifestyle of the general public -- the solar decathlon house is designed to support all the power needs of a typical household, including lighting, cooking, heating and cooling, and telecommunications. There should also be enough energy remaining to charge an electric vehicle for getting around. The competition requires the construction of the home "offsite". It should have a maximum dwelling footprint of 800 square feet, suitable for two people and mobile, so that it can be transported for a temporary exhibition "village," on the National Mall. The home has to be installed in four days, occupied and tested during the competition and then subsequently removed and shipped back to Austin. The University of Texas has participated in the competitions in 2002, 2005 and 2007
Telecommunications systems design techniques handbook
Handbook presents design and analysis of tracking, telemetry, and command functions utilized in these systems with particular emphasis on deep-space telecommunications. Antenna requirements are also discussed. Handbook provides number of tables outlining various performance criteria. Block diagrams and performance charts are also presented
Wind-tunnel model study of diffusion: Coalplex Project
July 1975.CER75-76RNM-JEC-JAG3.Includes bibliographical references.Prepared under contract to AE & CI Limited
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