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Did Emanuel Swedenborg Have Near-Death Experiences? Envisioning a Developmental Account of NDEs

Description: Article examining the phenomenological commonalities between Emanuel Swedenborg's experiences and near-death experiences (NDEs). It argues that a distal cause of Swedenborg's experiences was neural changes induced by his lifetime of unusual respiration, in conjunction with a predisposition to temporal lobe seizures. It concludes by proposing a number of empirically testable hypotheses emerging from the arguments, centered around a developmental approach to NDEs.
Date: Spring 2009
Creator: Jones, Simon R. & Fernyhough, Charles
Partner: UNT Libraries

Wake effects in a Fayette 95-IIS wind turbine array

Description: A group of 35 wind turbines on the Castello Ranch in Altamont Pass, California, was investigated to quantify array wake effects (losses in energy production due to operation of upwind turbines) and the factors influencing them. Approximately 65 hours of field measurements were made in summer 1986, with turbine energy production and wind velocity data recorded for various scenarios of array operation. Customized software and hardware were developed and installed by Fayette to facilitate these measurements. The existence of wake effects was fairly well established. Relative energy-production losses averaged 6% at the second row, when the first row was operating, and 7 to 8% at the third row, when the first two were operating. Apparently, then, the impact of the first row on the third (at a 21-rotor-diameter distance) was minimal. Ambient wind speed did not appear to affect the relative wind speed pattern within the array due to wakes, but because of the shape of the performance curve, it did affect relative energy production losses (particularly for the low-RPM mode of machine operation). The influences of ambient atmospheric conditions, such as stability, turbulence, and shear on the array wakes, were also investigated by testing over a range of the conditions available during a typical 24-hour day at the test site. None of these variables showed any significant effect on the degree of wake-induced energy losses. While the results of this study apply only to this specific array and type of wind turbine, the methodology could be applied to study wake effects at other wind farms. 6 refs., 7 figs., 20 tabs.
Date: September 1, 1987
Creator: Simon, R.L.; Matson, D.F. & Fuchs, J.M.
Partner: UNT Libraries Government Documents Department

Design, Construction, and Initial Operation of General Atomic In-Pile Loop

Description: From preface: To test the HTGR fuel-element design under environmental conditions of radiation, temperature, and pressure that approximate those in the Peach Bottom core and to test the operability of a dynamic system containing a vented graphite-clad fuel element.
Date: February 15, 1965
Creator: Simon, R. H.
Partner: UNT Libraries Government Documents Department

Confocal (micro)-XRF for 3D anlaysis of elements distribution in hot environmental particles

Description: Studies on the fate and transport of radioactive contaminates in the environment are often constrained by a lack of knowledge on the elemental distribution and general behavior of particulate bound radionuclides contained in hot particles. A number of hot particles were previously isolated from soil samples collected at former U.S. nuclear test sites in the Marshall Islands and characterized using non-destructive techniques [1]. The present investigation at HASYLAB is a part of larger research program at ITU regarding the characterization of environmental radioactive particles different locations and source-terms. Radioactive particles in the environment are formed under a number of different release scenarios and, as such, their physicochemical properties may provide a basis for identifying source-term specific contamination regimes. Consequently, studies on hot particles are not only important in terms of studying the elemental composition and geochemical behavior of hot particles but may also lead to advances in assessing the long-term impacts of radioactive contamination on the environment. Six particles isolated from soil samples collected at the Marshall Islands were studied. The element distribution in the particles was determined by confocal {micro}-XRF analysis using the ANKA FLUO beam line. The CRL (compound refractive lens) was used to focus the exciting beam and the polycapillary half lens to collimate the detector. The dimensions of confocal spot were measured by 'knife edge scanning' method with thin gold structure placed at Si wafer. The values of 3.1 x 1.4 x 18.4 {micro}m were achieved if defined as FWHMs of measured L?intensity profiles and when the19.1 keV exciting radiation was used. The collected XRF spectra were analyzed offline with AXIL [2] software to obtain net intensities of element characteristic lines.Further data processing and reconstruction of element distribution was done with the software 'R' [3] dedicated for statistical calculations. In figure 1 the distributions of Pu, ...
Date: November 27, 2007
Creator: Bielewski, M; Eriksson, M; Himbert, J; Simon, R; Betti, M & Hamilton, T F
Partner: UNT Libraries Government Documents Department

High Resolution PET with 250 micrometer LSO Detectors and Adaptive Zoom

Description: There have been impressive improvements in the performance of small-animal positron emission tomography (PET) systems since their first development in the mid 1990s, both in terms of spatial resolution and sensitivity, which have directly contributed to the increasing adoption of this technology for a wide range of biomedical applications. Nonetheless, current systems still are largely dominated by the size of the scintillator elements used in the detector. Our research predicts that developing scintillator arrays with an element size of 250 {micro}m or smaller will lead to an image resolution of 500 {micro}m when using 18F- or 64Cu-labeled radiotracers, giving a factor of 4-8 improvement in volumetric resolution over the highest resolution research systems currently in existence. This proposal had two main objectives: (i) To develop and evaluate much higher resolution and efficiency scintillator arrays that can be used in the future as the basis for detectors in a small-animal PET scanner where the spatial resolution is dominated by decay and interaction physics rather than detector size. (ii) To optimize one such high resolution, high sensitivity detector and adaptively integrate it into the existing microPET II small animal PET scanner as a 'zoom-in' detector that provides higher spatial resolution and sensitivity in a limited region close to the detector face. The knowledge gained from this project will provide valuable information for building future PET systems with a complete ring of very high-resolution detector arrays and also lay the foundations for utilizing high-resolution detectors in combination with existing PET systems for localized high-resolution imaging.
Date: January 8, 2012
Creator: Cherry, Simon R. & Qi, Jinyi
Partner: UNT Libraries Government Documents Department

Ultra-Precise Assembly of Micro-Electromechanical Systems (MEMS) Components

Description: This report summarizes a three year effort to develop an automated microassembly workcell for the assembly of LIGA (Lithography Galvonoforming Abforming) parts. Over the last several years, Sandia has developed processes for producing surface machined silicon and LIGA parts for use in weapons surety devices. Some of these parts have outside dimensions as small as 100 micron, and most all have submicron tolerances. Parts this small and precise are extremely difficult to assembly by hand. Therefore, in this project, we investigated the technologies required to develop a robotic workcell to assembly these parts. In particular, we concentrated on micro-grippers, visual servoing, micro-assembly planning, and parallel assembly. Three different micro-grippers were tested: a pneumatic probe, a thermally actuated polysilicon tweezer, and a LIGA fabricated tweezer. Visual servoing was used to accuracy position two parts relative to one another. Fourier optics methods were used to generate synthetic microscope images from CAD drawings. These synthetic images are used off-line to test image processing routines under varying magnifications and depths of field. They also provide reference image features which are used to visually servo the part to the desired position. We also investigated a new aspect of fine motion planning for the micro-domain. As parts approach 1-10 {micro}m or less in outside dimensions, interactive forces such as van der Waals and electrostatic forces become major factors which greatly change the assembly sequence and path plans. We developed the mathematics required to determine the goal regions for pick up, holding, and release of a micro-sphere being handled by a rectangular tool. Finally, we implemented and tested the ability to assemble an array of LIGA parts attached to two 3 inch diameter wafers. In this way, hundreds of parts can be assembled in parallel rather than assembling each part individually.
Date: April 1, 1999
Creator: Feddema, J.T.; Simon, R.; Polosky, M. & Christenson, T.
Partner: UNT Libraries Government Documents Department

Measuring worst-case errors in a robot workcell

Description: Errors in model parameters, sensing, and control are inevitably present in real robot systems. These errors must be considered in order to automatically plan robust solutions to many manipulation tasks. Lozano-Perez, Mason, and Taylor proposed a formal method for synthesizing robust actions in the presence of uncertainty; this method has been extended by several subsequent researchers. All of these results presume the existence of worst-case error bounds that describe the maximum possible deviation between the robot`s model of the world and reality. This paper examines the problem of measuring these error bounds for a real robot workcell. These measurements are difficult, because of the desire to completely contain all possible deviations while avoiding bounds that are overly conservative. The authors present a detailed description of a series of experiments that characterize and quantify the possible errors in visual sensing and motion control for a robot workcell equipped with standard industrial robot hardware. In addition to providing a means for measuring these specific errors, these experiments shed light on the general problem of measuring worst-case errors.
Date: October 1997
Creator: Simon, R. W.; Brost, R. C. & Kholwadwala, D. K.
Partner: UNT Libraries Government Documents Department

CAD-driven microassembly and visual servoing

Description: This paper describes current research and development on a robotic visual servoing system for assembly of LIGA (Lithography Galvonoforming Abforming) parts. The workcell consists of an AMTI robot, precision stage, long working distance microscope, and LIGA fabricated tweezers for picking up the parts. Fourier optics methods are used to generate synthetic microscope images from CAD drawings. These synthetic images are used off-line to test image processing routines under varying magnifications and depths of field, They also provide reference image features which are used to visually servo the part to the desired position.
Date: March 10, 1998
Creator: Feddema, J.T. & Simon, R.W.
Partner: UNT Libraries Government Documents Department

Exploratory research, Tasks A, B, C, and D. Final report, August 17-December 31, 1977

Description: SRI International has conducted research on the upgrading of computerized thermo-hydro code calculations and the synthesis of energetic materials. This project comprised four tasks, as follows: Task A included: (1) formulating routines for inverting the P = P(T,V) and V = V(T,P) equations of state when isotherms exhibit a van der Waals' loop; (2) incorporating these routines into the TIGER code so V and T can be used as independent variables in computing thermodynamic functions of liquids exhibiting a van der Waals' loop; (3) using these routines to incorporate into TIGER the prototype equation of state for liquids formulated at LLL by Dr. E.L. Lee; and (4) modifying TIGER routines to perform thermodynamic calculations when the concentrations of the gaseous species become zero. In Task B, a homopolymer of fluorodinitroethyl vinyl ether was obtained as a white, cotton-like material by bulk cationic polymerization. Work was begun on solution polymerization of fluorodinitroethyl vinyl ether. During Task C, studies were conducted on the synthesis of energetic compounds, especially hexanitrobenzene (HNB). The following areas were investigated: (1) nitration of phloroglucinol trioxime; (2) reaction of nitroaromatics with hydroxylamine; (3) oxidation of triaminotrinitrobenzene (TATB) with nitric acid; (4) oxidations with trifluoroperacetic acid, (5) oxidations with ozone; and (6) oxidations with chromic anhydride under anhydrous conditions. In Task D, known literature syntheses were examined and applied to the synthesis of new polymeric binders. An attractive scheme for the synthesis and polymerization of 2,3-disubstituted oxetanes is reported.
Date: February 17, 1978
Creator: Simon, R L; Coon, C L; Cowperthwaite, M & Sincich, E
Partner: UNT Libraries Government Documents Department

Wind energy resource atlas. Volume 9. The Southwest Region

Description: This atlas of the wind energy resource is composed of introductory and background information, a regional summary of the wind resource, and assessments of the wind resource in Nevada and California. Background on how the wind resource is assessed and on how the results of the assessment should be interpreted is presented. A description of the wind resource on a regional scale is then given. The results of the wind energy assessments for each state are assembled into an overview and summary of the various features of the regional wind energy resource. An introduction and outline to the descriptions of the wind resource given for each state are given. Assessments for individual states are presented as separate chapters. The state wind energy resources are described in greater detail than is the regional wind energy resource, and features of selected stations are discussed.
Date: November 1, 1980
Creator: Simon, R.L.; Norman, G.T.; Elliott, D.L.; Barchet, W.R. & George, R.L.
Partner: UNT Libraries Government Documents Department

Micro-grippers for assembly of LIGA parts

Description: This paper describes ongoing testing of two microgrippers for assembly of LIGA (Lithographie Galvanoformung Abformung) parts. The goal is to place 100 micron outside diameter (OD) LIGA gears with a 50 micron inner diameter hole onto pins ranging from 35 to 49 microns. The first micro gripper is a vacuum gripper made of a 100 micron OD stainless steel tube. The second micro gripper is a set of tweezers fabricated using the LIGA process. Nickel, Permalloy, and copper materials are tested. The tweezers are actuated by a collet mechanism which is closed by a DC linear motor.
Date: December 31, 1997
Creator: Feddema, J.; Polosky, M.; Christenson, T.; Spletzer, B. & Simon, R.
Partner: UNT Libraries Government Documents Department

Locating the magnetic center of the SSC CDM using a temporary quadrupole field

Description: The SSC dipole magnets must be very accurately aligned for the accelerator to work correctly. To align the magnets one must accurately know the center of the magnetic field. However, locating the center is difficult because of the extreme uniformity of the dipole field. A technique has been developed to determine the magnetic center of the SSC dipole magnet under ambient test conditions. This technique involves flowing current in the upper half of the coils in the direction opposite to the current in the lower half. This is done using a temporary lead connected to the splice joining the two coil halves and two matched power supplies. The resulting field is primarily skew quadrupole and has high field gradients which allow the center to be accurately located. The viability of this method has been verified by analysis using Taylor series expansion of the resulting magnetic field. Analysis has also verified that off-the-shelf power supplies have low enough mismatch to be used in this technique. The analytical results have been verified through the test of a short dipole magnet at the Brookhaven National Laboratory.
Date: December 31, 1992
Creator: Gibson, C. R.; Bliss, D. W.; Simon, R. E.; Jain, A. K. & Wanderer, P.
Partner: UNT Libraries Government Documents Department

Characterization and Source Term Assessments of Radioactive Particles from Marshall Islands Using Non-Destructive Analytical Techniques

Description: A considerable fraction of radioactivity entering the environment from different nuclear events is associated with particles. The impact of these events can only be fully assessed where there is some knowledge about the mobility of particle bound radionuclides entering the environment. The behavior of particulate radionuclides is dependent on several factors, including the physical, chemical and redox state of the environment, the characteristics of the particles (e.g., the chemical composition, crystallinity and particle size) and on the oxidative state of radionuclides contained in the particles. Six plutonium-containing particles stemming from Runit Island soil (Marshall Islands) were characterized using non-destructive analytical and microanalytical methods. By determining the activity of {sup 239,240}Pu and {sup 241}Am isotopes from their gamma peaks structural information related to Pu matrix was obtained, and the source term was revealed. Composition and elemental distribution in the particles were studied with synchrotron radiation based micro X-ray fluorescence (SR-{mu}-XRF) spectrometry. Scanning electron microscope equipped with energy dispersive X-ray detector (SEMEDX) and secondary ion mass spectrometer (SIMS) were used to examine particle surfaces. Based on the elemental composition the particles were divided into two groups; particles with plain Pu matrix, and particles where the plutonium is included in Si/O-rich matrix being more heterogeneously distributed. All of the particles were identified as fragments of initial weapons material. As containing plutonium with low {sup 240}Pu/{sup 239}Pu atomic ratio, {approx}2-6%, which corresponds to weapons grade plutonium, the source term was identified to be among the safety tests conducted in the history of Runit Island.
Date: June 11, 2005
Creator: Jernstrom, J; Eriksson, M; Simon, R; Tamborini, G; Bildstein, O; Carlos-Marquez, R et al.
Partner: UNT Libraries Government Documents Department

A molecular link between stem cell regulation and floral patterning in Arabidopsis.

Description: OAK-B135 The homeotic gene AGAMOUS (AG) has dual roles in specifying floral organ fate and limiting stem cell proliferation in Arabidopsis flowers. We show here that the floral identity protein LEAFY (LFY), a transcription factor expressed throughout the flower, acts together with the homeodomain protein WUSCHEL (WUS) to activate AG in the center of flowers. WUS was previously identified because of its role in maintaining a stem cell population in the center of both shoot and floral meristems. The unsuspected additional role of WUS in regulating floral homeotic gene expression supports the hypothesis that floral patterning makes use of a general meristem patterning system that was present before flowers evolved. We also show that AG represses WUS at later stages of floral development, thus creating a negative feedback loop that is required for the determinate growth of floral meristems.
Date: June 15, 2001
Creator: Lohmann, J. U., Hong, R. L., Hobe, M., Busch, M. A., Parcy, F., Simon, R., and Weigel, D.
Partner: UNT Libraries Government Documents Department

Aligning ontologies and integrating textual evidence for pathway analysis of microarray data

Description: Expression arrays are introducing a paradigmatic change in biology by shifting experimental approaches from single gene studies to genome-level analysis, monitoring the ex-pression levels of several thousands of genes in parallel. The massive amounts of data obtained from the microarray data needs to be integrated and interpreted to infer biological meaning within the context of information-rich pathways. In this paper, we present a methodology that integrates textual information with annotations from cross-referenced ontolo-gies to map genes to pathways in a semi-automated way. We illustrate this approach and compare it favorably to other tools by analyzing the gene expression changes underlying the biological phenomena related to stroke. Stroke is the third leading cause of death and a major disabler in the United States. Through years of study, researchers have amassed a significant knowledge base about stroke, and this knowledge, coupled with new technologies, is providing a wealth of new scientific opportunities. The potential for neu-roprotective stroke therapy is enormous. However, the roles of neurogenesis, angiogenesis, and other proliferative re-sponses in the recovery process following ischemia and the molecular mechanisms that lead to these processes still need to be uncovered. Improved annotation of genomic and pro-teomic data, including annotation of pathways in which genes and proteins are involved, is required to facilitate their interpretation and clinical application. While our approach is not aimed at replacing existing curated pathway databases, it reveals multiple hidden relationships that are not evident with the way these databases analyze functional groupings of genes from the Gene Ontology.
Date: October 8, 2006
Creator: Gopalan, Banu; Posse, Christian; Sanfilippo, Antonio P.; Stenzel-Poore, Mary; Stevens, S.L.; Castano, Jose et al.
Partner: UNT Libraries Government Documents Department

Dynamic Star Formation in the Massive DR21 Filament

Description: The formation of massive stars is a highly complex process in which it is unclear whether the star-forming gas is in global gravitational collapse or an equilibrium state supported by turbulence and/or magnetic fields. By studying one of the most massive and dense star-forming regions in the Galaxy at a distance of less than 3 kpc, i.e. the filament containing the well-known sources DR21 and DR21(OH), we attempt to obtain observational evidence to help us to discriminate between these two views. We use molecular line data from our {sup 13}CO 1 {yields} 0, CS 2 {yields} 1, and N{sub 2}H{sup +} 1 {yields} 0 survey of the Cygnus X region obtained with the FCRAO and CO, CS, HCO{sup +}, N{sub 2}H{sup +}, and H{sub 2}CO data obtained with the IRAM 30m telescope. We observe a complex velocity field and velocity dispersion in the DR21 filament in which regions of the highest column-density, i.e., dense cores, have a lower velocity dispersion than the surrounding gas and velocity gradients that are not (only) due to rotation. Infall signatures in optically thick line profiles of HCO{sup +} and {sup 12}CO are observed along and across the whole DR21 filament. By modelling the observed spectra, we obtain a typical infall speed of {approx}0.6 km s{sup -1} and mass accretion rates of the order of a few 10{sup -3} M{sub {circle_dot}} yr{sup -1} for the two main clumps constituting the filament. These massive clumps (4900 and 3300 M{sub {circle_dot}} at densities of around 10{sup 5} cm{sup -3} within 1 pc diameter) are both gravitationally contracting. The more massive of the clumps, DR21(OH), is connected to a sub-filament, apparently 'falling' onto the clump. This filament runs parallel to the magnetic field. Conclusions. All observed kinematic features in the DR21 filament (velocity field, velocity dispersion, and infall), ...
Date: August 25, 2010
Creator: Schneider, N.; /Saclay; Csengeri, T.; /Saclay; Bontemps, S.; /OASU, Floirac et al.
Partner: UNT Libraries Government Documents Department

Locating the magnetic center of the SSC CDM using a temporary quadrupole field

Description: The SSC dipole magnets must be very accurately aligned for the accelerator to work correctly. To align the magnets one must accurately know the center of the magnetic field. However, locating the center is difficult because of the extreme uniformity of the dipole field. A technique has been developed to determine the magnetic center of the SSC dipole magnet under ambient test conditions. This technique involves flowing current in the upper half of the coils in the direction opposite to the current in the lower half. This is done using a temporary lead connected to the splice joining the two coil halves and two matched power supplies. The resulting field is primarily skew quadrupole and has high field gradients which allow the center to be accurately located. The viability of this method has been verified by analysis using Taylor series expansion of the resulting magnetic field. Analysis has also verified that off-the-shelf power supplies have low enough mismatch to be used in this technique. The analytical results have been verified through the test of a short dipole magnet at the Brookhaven National Laboratory.
Date: January 1, 1992
Creator: Gibson, C.R.; Bliss, D.W.; Simon, R.E. (General Dynamics Corp., San Diego, CA (United States). Space Systems Div.); Jain, A.K. & Wanderer, P. (Brookhaven National Lab., Upton, NY (United States))
Partner: UNT Libraries Government Documents Department

The Atacama Cosmology Telescope: Cosmology from Galaxy Clusters Detected via the Sunyaev-Zel'dovich Effect

Description: We present constraints on cosmological parameters based on a sample of Sunyaev-Zeldovich-selected galaxy clusters detected in a millimeter-wave survey by the Atacama Cosmology Telescope. The cluster sample used in this analysis consists of 9 optically-confirmed high-mass clusters comprising the high-significance end of the total cluster sample identified in 455 square degrees of sky surveyed during 2008 at 148GHz. We focus on the most massive systems to reduce the degeneracy between unknown cluster astrophysics and cosmology derived from SZ surveys. We describe the scaling relation between cluster mass and SZ signal with a 4-parameter fit. Marginalizing over the values of the parameters in this fit with conservative priors gives {sigma}{sub 8} = 0.851 {+-} 0.115 and w = -1.14 {+-} 0.35 for a spatially-flat wCDM cosmological model with WMAP 7-year priors on cosmological parameters. This gives a modest improvement in statistical uncertainty over WMAP 7-year constraints alone. Fixing the scaling relation between cluster mass and SZ signal to a fiducial relation obtained from numerical simulations and calibrated by X-ray observations, we find {sigma}{sub 8} = 0.821 {+-} 0.044 and w = -1.05 {+-} 0.20. These results are consistent with constraints from WMAP 7 plus baryon acoustic oscillations plus type Ia supernoava which give {sigma}{sub 8} = 0.802 {+-} 0.038 and w = -0.98 {+-} 0.053. A stacking analysis of the clusters in this sample compared to clusters simulated assuming the fiducial model also shows good agreement. These results suggest that, given the sample of clusters used here, both the astrophysics of massive clusters and the cosmological parameters derived from them are broadly consistent with current models.
Date: August 18, 2011
Creator: Sehgal, Neelima; Trac, Hy; Acquaviva, Viviana; Ade, Peter A.R.; Aguirre, Paula; Amiri, Mandana et al.
Partner: UNT Libraries Government Documents Department