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Capabilities, methodologies, and use of the cambio file-translation application

Lasche, George

This report describes the capabilities, methodologies, and uses of the Cambio computer application, designed to automatically read and display nuclear spectral data files of any known format in the world and to convert spectral data to one of several commonly used analysis formats. To further assist responders, Cambio incorporates an analysis method based on non-linear fitting techniques found in open literature and implemented in openly published source code in the late 1980s. A brief description is provided of how Cambio works, of what basic formats it can currently read, and how it can be used. Cambio was developed at Sandia National Laboratories and is provided as a free service to assist nuclear emergency response analysts anywhere in the world in the fight against nuclear terrorism.

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TYPE SAND Report YEAR 2007
DOIOSTI

Macro-meso-microsystems integration in LTCC : LDRD report

Rohde, Steven B.; Okandan, Murat; Pfeifer, Kent B.; De Smet, Dennis; Patel, Kamlesh; Ho, Clifford K.; Nordquist, Christopher D.; Walker, Charles; Rohrer, Brandon R.; Buerger, Stephen P.; Turner, Timothy; Wroblewski, Brian W.

Low Temperature Cofired Ceramic (LTCC) has proven to be an enabling medium for microsystem technologies, because of its desirable electrical, physical, and chemical properties coupled with its capability for rapid prototyping and scalable manufacturing of components. LTCC is viewed as an extension of hybrid microcircuits, and in that function it enables development, testing, and deployment of silicon microsystems. However, its versatility has allowed it to succeed as a microsystem medium in its own right, with applications in non-microelectronic meso-scale devices and in a range of sensor devices. Applications include silicon microfluidic ''chip-and-wire'' systems and fluid grid array (FGA)/microfluidic multichip modules using embedded channels in LTCC, and cofired electro-mechanical systems with moving parts. Both the microfluidic and mechanical system applications are enabled by sacrificial volume materials (SVM), which serve to create and maintain cavities and separation gaps during the lamination and cofiring process. SVMs consisting of thermally fugitive or partially inert materials are easily incorporated. Recognizing the premium on devices that are cofired rather than assembled, we report on functional-as-released and functional-as-fired moving parts. Additional applications for cofired transparent windows, some as small as an optical fiber, are also described. The applications described help pave the way for widespread application of LTCC to biomedical, control, analysis, characterization, and radio frequency (RF) functions for macro-meso-microsystems.

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TYPE SAND Report YEAR 2007
DOIOSTI

On the application of computational fluid dynamics codes for liquefied natural gas dispersion

Journal of Hazardous Materials

Luketa-Hanlin, Anay; Koopman, Ronald P.; Ermak, Donald L.

Computational fluid dynamics (CFD) codes are increasingly being used in the liquefied natural gas (LNG) industry to predict natural gas dispersion distances. This paper addresses several issues regarding the use of CFD for LNG dispersion such as specification of the domain, grid, boundary and initial conditions. A description of the k-ε model is presented, along with modifications required for atmospheric flows. Validation issues pertaining to the experimental data from the Burro, Coyote, and Falcon series of LNG dispersion experiments are also discussed. A description of the atmosphere is provided as well as discussion on the inclusion of the Coriolis force to model very large LNG spills. © 2006 Elsevier B.V. All rights reserved.

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TYPE Journal Article YEAR 2007
ScopusOSTI

Markov Models and the Ensemble Kalman Filter for Estimation of Sorption Rates

Sandia journal manuscript; Not yet accepted for publication

Vugrin, Eric; Mckenna, Sean A.; Vugrin, Kay E.W.

Non-equilibrium sorption of contaminants in ground water systems is examined from the perspective of sorption rate estimation. A previously developed Markov transition probability model for solute transport is used in conjunction with a new conditional probability-based model of the sorption and desorption rates based on breakthrough curve data. Two models for prediction of spatially varying sorption and desorption rates along a one-dimensional streamline are developed. These models are a Markov model that utilizes conditional probabilities to determine the rates and an ensemble Kalman filter (EKF) applied to the conditional probability method. Both approaches rely on a previously developed Markov-model of mass transfer, and both models assimilate the observed concentration data into the rate estimation at each observation time. Initial values of the rates are perturbed from the true values to form ensembles of rates and the ability of both estimation approaches to recover the true rates is examined over three different sets of perturbations. The models accurately estimate the rates when the mean of the perturbations are zero, the unbiased case. Finally, for the cases containing some bias, addition of the ensemble Kalman filter is shown to improve accuracy of the rate estimation by as much as an order of magnitude.

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TYPE Presentation YEAR 2007
OSTI

Advanced imaging of multiple mRNAs in brain tissue using a custom hyperspectral imager and multivariate curve resolution

Journal of Neuroscience Methods

Sutherland, Vicki L.; Timlin, Jerilyn A.; Nieman, Linda T.; Guzowski, John F.; Chawla, Monica K.; Worley, Paul F.; Roysam, Badri; McNaughton, Bruce L.; Sinclair, Michael B.; Barnes, Carol A.

Simultaneous imaging of multiple cellular components is of tremendous importance in the study of complex biological systems, but the inability to use probes with similar emission spectra and the time consuming nature of collecting images on a confocal microscope are prohibitive. Hyperspectral imaging technology, originally developed for remote sensing applications, has been adapted to measure multiple genes in complex biological tissues. A spectral imaging microscope was used to acquire overlapping fluorescence emissions from specific mRNAs in brain tissue by scanning the samples using a single fluorescence excitation wavelength. The underlying component spectra obtained from the samples are then separated into their respective spectral signatures using multivariate analyses, enabling the simultaneous quantitative measurement of multiple genes either at regional or cellular levels. © 2006 Elsevier B.V. All rights reserved.

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TYPE Journal Article YEAR 2007
ScopusOSTI

Wire initiation critical for radiation symmetry in Z-pinch-driven dynamic hohlraums

Physical Review Letters

Sanford, T.W.L.; Jennings, C.A.; Rochau, G.A.; Rosenthal, Stephen E.; Sarkisov, G.S.; Sasorov, P.V.; Stygar, William A.; Bennett, Lawrence F.; Bliss, David E.; Chittenden, J.P.; Cuneo, Michael E.; Haines, M.G.; Leeper, Ramon J.; Mock, R.C.; Nash, Thomas J.; Peterson, D.L.

Axial symmetry in x-ray radiation of wire-array z pinches is important for the creation of dynamic hohlraums used to compress inertial-confinement-fusion capsules. We present the first evidence that this symmetry is directly correlated with the magnitude of the negative radial electric field along the wire surface. This field (in turn) is inferred to control the initial energy deposition into the wire cores, as well as any current shorting to the return conductor. © 2007 The American Physical Society.

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TYPE Conference YEAR 2007
ScopusOSTI

Hierarchical probabilistic regionalization of volcanism for Sengan region, Japan

Geotechnical and Geological Engineering

Kulatilake, Pinnaduwa H.S.W.; Park, Jinyong; Balasingam, Pirahas; Mckenna, Sean A.

A 1 km square regular grid system created on the Universal Transverse Mercator zone 54 projected coordinate system is used to work with volcanism related data for Sengan region. The following geologic variables were determined as the most important for identifying volcanism: geothermal gradient, groundwater temperature, heat discharge, groundwater pH value, presence of volcanic rocks and presence of hydrothermal alteration. Data available for each of these important geologic variables were used to perform directional variogram modeling and kriging to estimate geologic variable vectors at each of the 23949 centers of the chosen 1 km cell grid system. Cluster analysis was performed on the 23949 complete variable vectors to classify each center of 1 km cell into one of five different statistically homogeneous groups with respect to potential volcanism spanning from lowest possible volcanism to highest possible volcanism with increasing group number. A discriminant analysis incorporating Bayes' theorem was performed to construct maps showing the probability of group membership for each of the volcanism groups. The said maps showed good comparisons with the recorded locations of volcanism within the Sengan region. No volcanic data were found to exist in the group 1 region. The high probability areas within group 1 have the chance of being the no volcanism region. Entropy of classification is calculated to assess the uncertainty of the allocation process of each 1 km cell center location based on the calculated probabilities. The recorded volcanism data are also plotted on the entropy map to examine the uncertainty level of the estimations at the locations where volcanism exists. The volcanic data cell locations that are in the high volcanism regions (groups 4 and 5) showed relatively low mapping estimation uncertainty. On the other hand, the volcanic data cell locations that are in the low volcanism region (group 2) showed relatively high mapping estimation uncertainty. The volcanic data cell locations that are in the medium volcanism region (group 3) showed relatively moderate mapping estimation uncertainty. Areas of high uncertainty provide locations where additional site characterization resources can be spent most effectively. The new data collected can be added to the existing database to perform future regionalized mapping and reduce the uncertainty level of the existing estimations. © Springer Science+Business Media B.V. 2006.

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TYPE Conference YEAR 2007
ScopusOSTI

Modal deposition of shock energy

Proposed for publication in Earthquake Engineering and Structural Dynamics.

Edwards, Timothy S.; Segalman, Daniel J.

A relatively new concept in the field of mechanical shock analysis has been introduced whereby an analysis is made on the work done on structures by the excitation force. The energy imparted to a structure by the excitation can then be divided into various storage and loss mechanisms within the structure. These energies can be used to both evaluate shock response severity and characterize the underlying excitation. Previous work has illustrated the many advantages of the energy methods over traditional shock response spectrum techniques. This work will show that the energy delivered to a MDOF system is uncoupled between modes. Therefore, the total deformational energy delivered to a MDOF system is a weighted sum of the uncoupled modal contributions. This leads to the ability to compute input energy on a modal basis using uncoupled, SDOF calculations. Further, the internal storage and loss energies are also uncoupled. When the input excitation is broadband, the energy input into a MDOF structure by ground motion is dominated by that mode with the largest fraction of participating mass, often the fundamental mode of the system. This leads to the justification for treating complex structures as SDOF oscillators when using energy methods to evaluate both the underlying excitation and the structural response.

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TYPE Journal Article YEAR 2007
OSTI
Results 82501–82600 of 99,299
Results 82501–82600 of 99,299