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100kW Energy Transfer Multiplexer Power Converter Prototype Development Project (open access)

100kW Energy Transfer Multiplexer Power Converter Prototype Development Project

Project Final Report for "100kW Energy Transfer Multiplexer Power Converter Prototype Development Project" prepared under DOE grant number DE-FG36-03GO13138. This project relates to the further development and prototype construction/evaluation for the Energy Transfer Multiplexer (ETM) power converter topology concept. The ETM uses a series resonant link to transfer energy from any phase of a multiphase input to any phase of a multiphase output, converting any input voltage and frequency to any output voltage and frequency. The basic form of the ETM converter consists of an eight (8)-switch matrix (six phase power switches and two ground power switches) and a series L-C resonant circuit. Electronic control of the switches allows energy to be transferred in the proper amount from any phase to any other phase. Depending upon the final circuit application, the switches may be either SCRs or IGBTs. The inherent characteristics of the ETM converter include the following: Power processing in either direction (bidirectional); Large voltage gain without the need of low frequency magnetics; High efficiency independent of output load and frequency; Wide bandwidth with fast transient response and; Operation as a current source. The ETM is able to synthesize true sinusoidal waveforms with low harmonic distortions. For a low …
Date: March 21, 2006
Creator: Skeist, S. Merrill; Baker, Richard H.; Marini, Anthony G. P. & Bennett, Keith
Object Type: Report
System: The UNT Digital Library
2006 Sensory Transduction in Microorganisms Gordon Conference - January 22-27 (open access)

2006 Sensory Transduction in Microorganisms Gordon Conference - January 22-27

This Report is Description of Sensory Transduction in Microorganisms at Gordon Conference.
Date: March 21, 2007
Creator: Borkovich, Katherine
Object Type: Article
System: The UNT Digital Library
Accessing the Inaccessible: The Case for Opening up Russia's Closed Cities (open access)

Accessing the Inaccessible: The Case for Opening up Russia's Closed Cities

The selling of weapons-related nuclear knowledge by Russian scientists for economic gain constitutes a threat to US national security. Some estimate that the number of Russian scientists seeking permanent employment abroad constitute five to ten percent of all researchers who have left the field of science. And, there is concern that those who have left are ''the better minds.'' Moreover, the issue of brain drain concerns not only those who move abroad permanently, but those who still reside in Russia and travel abroad to sell their knowledge. Of particular concern to the US is the potential sale of WMD knowledge by some. To ''mitigate the risk that economic difficulties...might create the temptation for individuals or institutes to sell expertise to countries of proliferation concern and terrorist organizations,'' the Department of Energy launched a Nuclear Cities Initiative (NCI) in 1998 with the goal of creating commercial jobs and economic diversification in the ten closed cities that form the core of Russia's nuclear weapons complex to accommodate the loss of employment in the nuclear weapons industry. However, unless Russia opens access to the areas of its closed cities that are, or could become, involved in commercial activities-while of course carefully controlling access …
Date: March 21, 2001
Creator: Ball, D Y
Object Type: Article
System: The UNT Digital Library
Active RF Pulse Compression Using Electrically Controlled Semiconductor Switches (open access)

Active RF Pulse Compression Using Electrically Controlled Semiconductor Switches

In this paper, we present the recent results of our research on the ultra-high power fast silicon RF switch and its application on active X-Band RF pulse compression systems. This switch is composed of a group of PIN diodes on a high purity silicon wafer and has achieved a switching time of 300ns. The wafer is inserted into a cylindrical waveguide operating in the TE01 mode. Switching is performed by injecting carriers into the bulk silicon through a high current pulse. The RF energy is stored in a room-temperature, high-Q 375 ns delay line; it is then extracted out of the line in a short time using the switch. The pulse compression system has achieved a gain of 8, which is the ratio between output and input power.
Date: March 21, 2007
Creator: Guo, J. & Tantawi, S.
Object Type: Article
System: The UNT Digital Library
Advances in HFE Methods and Their Implications for Regulatory Reviews. (open access)

Advances in HFE Methods and Their Implications for Regulatory Reviews.

There is renewed interest in the United States (U.S.) to construct new Generation III and III+ reactors within the next decade and Generation IV reactors in the future. Licensing by the U.S. Nuclear Regulatory Commission (NRC) is a significant consideration and these new plants may pose new challenges. One such challenge is the advances in human factors engineering (HFE) methods that are used. These methods are used to design and evaluate the HFE aspects of a plant, such as the human-system interface (HSI). These methods are important because NRC HFE reviews are design process oriented, thus, the criteria are mostly technology neutral with regard to reactor design.[1] However, the HFE review criteria are not neutral with respect to the HFE methods that are used as part of the design process This will be important for new reactor reviews because the diversity of reactor types, HSIs, and operational concepts will increase, especially for Generation III+ and IV plants. Thus the NRC is conducting research to identify advances in HFE methods and to develop additional guidance to address their review.
Date: March 21, 2006
Creator: O'hara, J.; Persensky, J. & Szabo, A.
Object Type: Article
System: The UNT Digital Library
Africa: U.S. Foreign Assistance Issues (open access)

Africa: U.S. Foreign Assistance Issues

This report discusses the issue of U.S. economic assistance to sub-Saharan Africa, highlighting the importance of continued assistance in light of U.S. national security and also various U.S.-led efforts to promote reform amongst African citizens themselves. U.S. assistance finds its way to Africa through a variety of channels, including the USAID-administered DA program, food aid programs, and indirect aid provided through international financial institutions and the United Nations.
Date: March 21, 2005
Creator: Copson, Raymond W.
Object Type: Report
System: The UNT Digital Library
Air Force FB-22 Bomber Concept (open access)

Air Force FB-22 Bomber Concept

The Air Force has expressed interest in developing a bomber variant of the F-22A Raptor to "bridge the gap" between today's bombers and a follow-on bomber in 2037. Questions exist regarding the FB-22's feasibility, cost, and combat potential.
Date: March 21, 2005
Creator: Bolkcom, Christopher
Object Type: Report
System: The UNT Digital Library

[Air Rifle Team line up for practice]

Photograph of members of the Paschal High School Air Rifle Team lined up for practice. Several boys are seen, though the photo is focused on the boy in the front, who has a buzzed haircut and wears safety glasses. They each point air rifles, red and blue and tan in color, to the right of the photograph. They are preparing for a national tournament in Georgia.
Date: March 21, 2005
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Air Rifle Team members at practice]

Photograph of members of the Pascal High School Air Rifle Team taking aim during a practice before a national tournament. Several boys are seen, though the photo is focused on the boy in the front, who has a buzzed haircut and wears safety glasses. They each point air rifles, red and blue and tan in color, towards the right of the photograph. The team is made up of members of the Junior Reserve Officer Training Corps. They are preparing for a national tournament in Georgia.
Date: March 21, 2005
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Air Rifle Team members practice for a tournament]

Fotografía de miembros del equipo de rifle aéreo del Cuerpo de Entrenamiento de Oficiales de la Reserva Junior en la Escuela Secundaria Paschal de Fort Worth durante una práctica. En la fotografía se ve a cuatro chicos, con el pelo cortado y con gafas de seguridad. Cada uno de ellos apunta con rifles de aire, de color rojo y azul y bronceado, a la derecha de la fotografía. Participan en un programa de educación premilitar que les permite viajar a Georgia para competir en un torneo nacional para ver si son los mejores del país.
Date: March 21, 2005
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Air Rifle Team practice at Paschal High School]

Photograph of members of the Pascal High School Air Rifle Team taking aim during a practice before a national tournament. Several boys are seen, though the photo is focused on the boy in the front, who has a buzzed haircut and wears safety glasses. They each point air rifles, red and blue and tan in color, to the right of the photograph. The team is made up of members of the Junior Reserve Officer Training Corps. They are preparing for a national tournament in Georgia.
Date: March 21, 2005
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library
The Albany News (Albany, Tex.), Vol. 126, No. 42, Ed. 1 Thursday, March 21, 2002 (open access)

The Albany News (Albany, Tex.), Vol. 126, No. 42, Ed. 1 Thursday, March 21, 2002

Weekly newspaper from Albany, Texas that includes local, county, and state news along with extensive advertising.
Date: March 21, 2002
Creator: Lucas, Melinda L.
Object Type: Newspaper
System: The Portal to Texas History
Altus Times (Altus, Okla.), Vol. 101, No. 6, Ed. 1 Tuesday, March 21, 2000 (open access)

Altus Times (Altus, Okla.), Vol. 101, No. 6, Ed. 1 Tuesday, March 21, 2000

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 21, 2000
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Altus Times (Altus, Okla.), Vol. 102, No. 6, Ed. 1 Wednesday, March 21, 2001 (open access)

Altus Times (Altus, Okla.), Vol. 102, No. 6, Ed. 1 Wednesday, March 21, 2001

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 21, 2001
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Altus Times (Altus, Okla.), Vol. 104, No. 6, Ed. 1 Thursday, March 21, 2002 (open access)

Altus Times (Altus, Okla.), Vol. 104, No. 6, Ed. 1 Thursday, March 21, 2002

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 21, 2002
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Altus Times (Altus, Okla.), Vol. 105, No. 316, Ed. 1 Sunday, March 21, 2004 (open access)

Altus Times (Altus, Okla.), Vol. 105, No. 316, Ed. 1 Sunday, March 21, 2004

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 21, 2004
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
Altus Times (Altus, Okla.), Vol. 106, No. 296, Ed. 1 Monday, March 21, 2005 (open access)

Altus Times (Altus, Okla.), Vol. 106, No. 296, Ed. 1 Monday, March 21, 2005

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 21, 2005
Creator: Andrews, Mike
Object Type: Newspaper
System: The Gateway to Oklahoma History
Altus Times (Altus, Okla.), Vol. 107, No. 297, Ed. 1 Tuesday, March 21, 2006 (open access)

Altus Times (Altus, Okla.), Vol. 107, No. 297, Ed. 1 Tuesday, March 21, 2006

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 21, 2006
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Altus Times (Altus, Okla.), Vol. 108, No. 305, Ed. 1 Wednesday, March 21, 2007 (open access)

The Altus Times (Altus, Okla.), Vol. 108, No. 305, Ed. 1 Wednesday, March 21, 2007

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 21, 2007
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Altus Times (Altus, Okla.), Vol. 109, No. 251, Ed. 1 Friday, March 21, 2008 (open access)

The Altus Times (Altus, Okla.), Vol. 109, No. 251, Ed. 1 Friday, March 21, 2008

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: March 21, 2008
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
The Alvin Advertiser (Alvin, Tex.), Ed. 1 Wednesday, March 21, 2001 (open access)

The Alvin Advertiser (Alvin, Tex.), Ed. 1 Wednesday, March 21, 2001

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: March 21, 2001
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Alvin Sun-Advertiser (Alvin, Tex.), Vol. 114, No. 23, Ed. 1 Sunday, March 21, 2004 (open access)

Alvin Sun-Advertiser (Alvin, Tex.), Vol. 114, No. 23, Ed. 1 Sunday, March 21, 2004

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: March 21, 2004
Creator: Schwind, Jim & Looby, Edward
Object Type: Newspaper
System: The Portal to Texas History
Amendments on the House Floor: Summary of Major Restrictions (open access)

Amendments on the House Floor: Summary of Major Restrictions

This report is a summary of Major Restrictions regarding Amendments on the House Floor.
Date: March 21, 2007
Creator: Schneider, Judy
Object Type: Report
System: The UNT Digital Library
Analysis of hazardous biological material by MALDI mass spectrometry (open access)

Analysis of hazardous biological material by MALDI mass spectrometry

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-MS) has become a valuable tool for analyzing microorganisms. The speed with which data can be obtained from MALDI-MS makes this a potentially important tool for biological health hazard monitoring and forensic applications. The excitement in the mass spectrometry community in this potential field of application is evident by the expanding list of research laboratories pursuing development of MALDI-MS for bacterial identification. Numerous research groups have demonstrated the ability to obtain unique MALDI-MS spectra from intact bacterial cells and bacterial cell extracts. The ability to differentiate strains of the same species has been investigated. Reproducibility of MALDI-MS spectra from bacterial species under carefully controlled experimental conditions has also been demonstrated. Wang et al. have reported on interlaboratory reproducibility of the MALDI-MS analysis of several bacterial species. However, there are still issues that need to be addressed, including the careful control of experimental parameters for reproducible spectra and selection of optimal experimental parameters such as solvent and matrix.
Date: March 21, 2000
Creator: Wahl, K. L.; Jarman, K. H.; Valentine, N. B.; Kingsley, M. T.; Petersen, C. E.; Cebula, S. T. et al.
Object Type: Report
System: The UNT Digital Library