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Liquid Hydrogen Absorber for MICE (open access)

Liquid Hydrogen Absorber for MICE

Liquid hydrogen absorbers for the Muon Ionization Cooling Experiment (MICE) have been developed, and the first absorber has been tested at KEK. In the preliminary test at KEK we have successfully filled the absorber with {approx}2 liters of liquid hydrogen. The measured hydrogen condensation speed was 2.5 liters/day at 1.0 bar. No hydrogen leakage to vacuum was found between 300 K and 20 K. The MICE experiment includes three AFC (absorber focusing coil) modules, each containing a 21 liter liquid hydrogen absorber made of aluminum. The AFC module has safety windows to separate its vacuum from that of neighboring modules. Liquid hydrogen is supplied from a cryocooler with cooling power 1.5 W at 4.2 K. The first absorber will be assembled in the AFC module and installed in MICE at RAL.
Date: May 30, 2010
Creator: Ishimoto, S.; Suzuki, S.; Yoshida, M.; Green, Michael A.; Kuno, Y. & Lau, Wing
Object Type: Article
System: The UNT Digital Library
Modeling and Measurement Constraints in Fault Diagnostics for HVAC Systems (open access)

Modeling and Measurement Constraints in Fault Diagnostics for HVAC Systems

Many studies have shown that energy savings of five to fifteen percent are achievable in commercial buildings by detecting and correcting building faults, and optimizing building control systems. However, in spite of good progress in developing tools for determining HVAC diagnostics, methods to detect faults in HVAC systems are still generally undeveloped. Most approaches use numerical filtering or parameter estimation methods to compare data from energy meters and building sensors to predictions from mathematical or statistical models. They are effective when models are relatively accurate and data contain few errors. In this paper, we address the case where models are imperfect and data are variable, uncertain, and can contain error. We apply a Bayesian updating approach that is systematic in managing and accounting for most forms of model and data errors. The proposed method uses both knowledge of first principle modeling and empirical results to analyze the system performance within the boundaries defined by practical constraints. We demonstrate the approach by detecting faults in commercial building air handling units. We find that the limitations that exist in air handling unit diagnostics due to practical constraints can generally be effectively addressed through the proposed approach.
Date: May 30, 2010
Creator: Najafi, Massieh; Auslander, David M.; Bartlett, Peter L.; Haves, Philip & Sohn, Michael D.
Object Type: Article
System: The UNT Digital Library
Search for the Higgs Boson in $H\to WW^{*}\to\ell\nu\ell\nu$ Decays (open access)

Search for the Higgs Boson in $H\to WW^{*}\to\ell\nu\ell\nu$ Decays

We present a search for the standard model (SM) Higgs boson decaying to a pair of W bosons that in turn decay leptonically, H {yields} WW* {yields} {ell}{nu}{ell}{nu}. We consider events produced in p{bar p} collisions at {radical}s = 1.96 TeV, with two oppositely charged lepton candidates (e{sup +}e{sup -}, e{sup {+-}}{mu}{sup {+-}}, or {mu}{sup +}{mu}{sup -}), and missing transverse energy. The data were collected with the D0 detector at the Fermilab Tevatron collider, and correspond to an integrated luminosity of 5.4 fb{sup -1}. No excess of events over background is observed, and limits on SM Higgs boson production are determined.
Date: May 30, 2010
Creator: Gerbaudo, Davide
Object Type: Article
System: The UNT Digital Library
Lessons Learned for the MICE Coupling Solenoid from the MICE Spectrometer Solenoids (open access)

Lessons Learned for the MICE Coupling Solenoid from the MICE Spectrometer Solenoids

Tests of the spectrometer solenoids have taught us some important lessons. The spectrometer magnet lessons learned fall into two broad categories that involve the two stages of the coolers that are used to cool the magnets. On the first spectrometer magnet, the problems were centered on the connection of the cooler 2nd-stage to the magnet cold mass. On the first test of the second spectrometer magnet, the problems were centered on the cooler 1st-stage temperature and its effect on the operation of the HTS leads. The second time the second spectrometer magnet was tested; the cooling to the cold mass was still not adequate. The cryogenic designs of the MICE and MuCOOL coupling magnets are quite different, but the lessons learned from the tests of the spectrometer magnets have affected the design of the coupling magnets.
Date: May 30, 2010
Creator: Green, Michael A.; Wang, Li; Pan, Heng; Wu, Hong; Guo, Xinglong; Li, S. Y. et al.
Object Type: Article
System: The UNT Digital Library
Sweetwater Reporter (Sweetwater, Tex.), Vol. 112, No. 167, Ed. 1 Sunday, May 30, 2010 (open access)

Sweetwater Reporter (Sweetwater, Tex.), Vol. 112, No. 167, Ed. 1 Sunday, May 30, 2010

Daily newspaper from Sweetwater, Texas that includes local, state, and national news along with advertising.
Date: May 30, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Evaluation of Reformer Produced Synthesis Gas for Emissions Reductions in Natural Gas Reciprocating Engines (open access)

Evaluation of Reformer Produced Synthesis Gas for Emissions Reductions in Natural Gas Reciprocating Engines

Rolls-Royce Fuel Cell Systems (US) Inc. (RRFCS) has developed a system that produces synthesis gas from air and natural gas. A near-term application being considered for this technology is synthesis gas injection into reciprocating engines for reducing NO{sub x} emissions. A proof of concept study using bottled synthesis gas and a two-stroke reciprocating engine showed that injecting small amounts of high-flammable content synthesis gas significantly improved combustion stability and enabled leaner engine operation resulting in over 44% reduction in NO{sub x} emissions. The actual NO{sub x} reduction that could be achieved in the field is expected to be engine specific, and in many cases may be even greater. RRFCS demonstrated that its synthesis gas generator could produce synthesis gas with the flammable content that was successfully used in the engine testing. An economic analysis of the synthesis gas approach estimates that its initial capital cost and yearly operating cost are less than half that of a competing NO{sub x} reduction technology, Selective Catalytic Reduction. The next step in developing the technology is an integrated test of the synthesis gas generator with an engine to obtain reliability data for system components and to confirm operating cost. RRFCS is actively pursuing opportunities …
Date: May 30, 2010
Creator: Scotto, Mark
Object Type: Report
System: The UNT Digital Library
Evaluation of Reformer Produced Synthesis Gas for Emissions Reductions in Natural Gas Reciprocating Engines (open access)

Evaluation of Reformer Produced Synthesis Gas for Emissions Reductions in Natural Gas Reciprocating Engines

Rolls-Royce Fuel Cell Systems (US) Inc. (RRFCS) has developed a system that produces synthesis gas from air and natural gas. A near-term application being considered for this technology is synthesis gas injection into reciprocating engines for reducing NOx emissions. A proof of concept study using bottled synthesis gas and a two-stroke reciprocating engine showed that injecting small amounts of highflammables content synthesis gas significantly improved combustion stability and enabled leaner engine operation resulting in over 44% reduction in NOx emissions. The actual NOx reduction that could be achieved in the field is expected to be engine specific, and in many cases may be even greater. RRFCS demonstrated that its synthesis gas generator could produce synthesis gas with the flammables content that was successfully used in the engine testing. An economic analysis of the synthesis gas approach estimates that its initial capital cost and yearly operating cost are less than half that of a competing NOx reduction technology, Selective Catalytic Reduction. The next step in developing the technology is an integrated test of the synthesis gas generator with an engine to obtain reliability data for system components and to confirm operating cost. RRFCS is actively pursuing opportunities to perform the integrated …
Date: May 30, 2010
Creator: Scotto, Mark V. & Perna, Mark A.
Object Type: Report
System: The UNT Digital Library
Retelling of Dana Wazir transcript

Retelling of Dana Wazir

Recording of Hasil Murad reciting "Dana Wazir," a popular story in the Hunza dialect of Burushaski.
Date: May 30, 2010
Creator: Karim, Piar
Object Type: Sound
System: The UNT Digital Library
Analysis Code for High Gradient Dielectric Insulator Surface Breakdown (open access)

Analysis Code for High Gradient Dielectric Insulator Surface Breakdown

High voltage (HV) insulators are critical components in high-energy, accelerator and pulsed power systems that drive diverse applications in the national security, nuclear weapons science, defense and industrial arenas. In these systems, the insulator may separate vacuum/non-vacuum regions or conductors with high electrical field gradients. These insulators will often fail at electric fields over an order of magnitude lower than their intrinsic dielectric strength due to flashover at the dielectric interface. Decades of studies have produced a wealth of information on fundamental processes and mechanisms important for flashover initiation, but only for relatively simple insulator configurations in controlled environments. Accelerator and pulsed power system designers are faced with applying the fundamental knowledge to complex, operational devices with escalating HV requirements. Designers are forced to rely on “best practices” and expensive prototype testing, providing boundaries for successful operation. However, the safety margin is difficult to estimate, and system design must be very conservative for situations where testing is not practicable, or replacement of failed parts is disruptive or expensive. The Phase I program demonstrated the feasibility of developing an advanced code for modeling insulator breakdown. Such a code would be of great interest for a number of applications, including high energy …
Date: May 30, 2010
Creator: Ives, Robert Lawrence; Verboncoeur, John & Aldan, Manuel
Object Type: Report
System: The UNT Digital Library
The Altus Times (Altus, Okla.), Vol. 112, No. 125, Ed. 1 Sunday, May 30, 2010 (open access)

The Altus Times (Altus, Okla.), Vol. 112, No. 125, Ed. 1 Sunday, May 30, 2010

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: May 30, 2010
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 95, No. 183, Ed. 1 Sunday, May 30, 2010 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 95, No. 183, Ed. 1 Sunday, May 30, 2010

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: May 30, 2010
Creator: Shance, Brenda
Object Type: Newspaper
System: The Gateway to Oklahoma History
Polk County Enterprise (Livingston, Tex.), Vol. 128, No. 43, Ed. 1 Sunday, May 30, 2010 (open access)

Polk County Enterprise (Livingston, Tex.), Vol. 128, No. 43, Ed. 1 Sunday, May 30, 2010

Semi-weekly newspaper from Livingston, Texas that includes local, state and national news along with advertising.
Date: May 30, 2010
Creator: Reddell, Valerie
Object Type: Newspaper
System: The Portal to Texas History
Visualization of Fuel Cell Water Transport and Performance Characterization under Freezing Conditions (open access)

Visualization of Fuel Cell Water Transport and Performance Characterization under Freezing Conditions

In this program, Rochester Institute of Technology (RIT), General Motors (GM) and Michigan Technological University (MTU) have focused on fundamental studies that address water transport, accumulation and mitigation processes in the gas diffusion layer and flow field channels of the bipolar plate. These studies have been conducted with a particular emphasis on understanding the key transport phenomena which control fuel cell operation under freezing conditions. Technical accomplishments are listed below: • Demonstrated that shutdown air purge is controlled predominantly by the water carrying capacity of the purge stream and the most practical means of reducing the purge time and energy is to reduce the volume of liquid water present in the fuel cell at shutdown. The GDL thermal conductivity has been identified as an important parameter to dictate water accumulation within a GDL. • Found that under the normal shutdown conditions most of the GDL-level water accumulation occurs on the anode side and that the mass transport resistance of the membrane electrode assembly (MEA) thus plays a critically important role in understanding and optimizing purge. • Identified two-phase flow patterns (slug, film and mist flow) in flow field channel, established the features of each pattern, and created a flow pattern …
Date: May 30, 2010
Creator: Kandlikar, Satish G.; Lu, Zijie; Rao, Navalgund; Sergi, Jacqueline; Rath, Cody; Mc Dade, Christopher et al.
Object Type: Report
System: The UNT Digital Library
The Panola Watchman (Carthage, Tex.), Vol. 138, No. 43, Ed. 1 Sunday, May 30, 2010 (open access)

The Panola Watchman (Carthage, Tex.), Vol. 138, No. 43, Ed. 1 Sunday, May 30, 2010

Semiweekly newspaper from Carthage, Texas that includes local, state, and national news along with advertising.
Date: May 30, 2010
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History