Etchells, Edward; Ferrari, Michel; Kiss, Alex; Martyn, Nikki; Zinman, Deborah; Levinson, Wendy
2011-06-01
Prior studies show significant gaps in the informed decision-making process, a central goal of surgical care. These studies have been limited by their focus on low-risk decisions, single visits rather than entire consultations, or both. Our objectives were, first, to rate informed decision-making for major elective vascular surgery based on audiotapes of actual physician-patient conversations and, second, to compare ratings of informed decision-making for first visits to ratings for multiple visits by the same patient over time. We prospectively enrolled patients for whom vascular surgical treatment was a potential option at a tertiary care outpatient vascular surgery clinic. We audio-taped all surgeon-patient conversations, including multiple visits when necessary, until a decision was made. Using an existing method, we evaluated the transcripts for elements of decision-making, including basic elements (e.g., an explanation of the clinical condition), intermediate elements (e.g., risks and benefits) and complex elements (e.g., uncertainty around the decision). We analyzed 145 surgeon-patient consultations. Overall, 45% of consultations contained complex elements, whereas 23% did not contain the basic elements of decision-making. For the 67 consultations that involved multiple visits, ratings were significantly higher when evaluating all visits (50% complex elements) compared with evaluating only the first visit (33% complex elements, p < 0.001.) We found that 45% of consultations contained complex elements, which is higher than prior studies with similar methods. Analyzing decision-making over multiple visits yielded different results than analyzing decision-making for single visits.
Conversion of microwave signals by superconducting films in the resistive state
NASA Technical Reports Server (NTRS)
Yeru, I. I.; Peskovatskiy, S. A.; Sulima, V. S.
1984-01-01
The main characteristics of a superconducting thin film microwave mixer, i.e., conversion efficiency and bandwidth are analyzed. The optimum operating regime of the nonlinear element is determined. Results of calculations are compared with the experimental ones. Experimental data on the noise in the superconducting films in a wide frequency range are presented.
OLED lighting devices having multi element light extraction and luminescence conversion layer
Krummacher, Benjamin Claus; Antoniadis, Homer
2010-11-16
An apparatus such as a light source has a multi element light extraction and luminescence conversion layer disposed over a transparent layer of the light source and on the exterior of said light source. The multi-element light extraction and luminescence conversion layer includes a plurality of light extraction elements and a plurality of luminescence conversion elements. The light extraction elements diffuses the light from the light source while luminescence conversion elements absorbs a first spectrum of light from said light source and emits a second spectrum of light.
NASA Astrophysics Data System (ADS)
Huang, Jianzhen
2018-01-01
In this paper, the surface conversion film on 6063 aluminum alloy was prepared by chemical plating process with chromium sulfate, lanthanum sulfate and sodium phosphate as film forming agent. The corrosion resistance and surface morphology of the conversion film were analyzed by pitting corrosion test of copper sulfate and SEM. The results show that when Cr2(SO4)3 is 10 g/L, La2(SO4)3 is 2 g/L, Na3PO4 is 8 g/L, pH value is 3, temperature is 40 °C, reaction time is 10 min, the corrosion resistance of the surface conversion film is the best. The conversion coating is light green, composed of Cr, La, P, Al, O and other elements.
Antoniadis,; Homer, Krummacher [Mountain View, CA; Claus, Benjamin [Regensburg, DE
2008-01-22
An apparatus such as a light source has a multi-element light extraction and luminescence conversion layer disposed over a transparent layer of the light source and on the exterior of said light source. The multi-element light extraction and luminescence conversion layer includes a plurality of light extraction elements and a plurality of luminescence conversion elements. The light extraction elements diffuses the light from the light source while luminescence conversion elements absorbs a first spectrum of light from said light source and emits a second spectrum of light.
A permanent magnet tubular linear generator for wave energy conversion
NASA Astrophysics Data System (ADS)
Yu, Haitao; Liu, Chunyuan; Yuan, Bang; Hu, Minqiang; Huang, Lei; Zhou, Shigui
2012-04-01
A novel three-phase permanent magnet tubular linear generator (PMTLG) with Halbach array is proposed for the sea wave energy conversion. Non-linear axi-symmetrical finite element method (FEM) is implemented to calculate the magnetic fields along air-gap for different Halbach arrays of PMTLGs. The PMTLG characteristics are analyzed and the simulation results are validated by the experiment. An assistant tooth is implemented to greatly minimize the end and cogging effects which cause the oscillatory detent force.
NASA Technical Reports Server (NTRS)
Natesh, R.; Smith, J. M.; Qidwai, H. A.; Bruce, T.
1979-01-01
The evaluation and prediction of the conversion efficiency for a variety of silicon samples with differences in structural defects, such as grain boundaries, twin boundaries, precipitate particles, dislocations, etc. are discussed. Quantitative characterization of these structural defects, which were revealed by etching the surface of silicon samples, is performed by using an image analyzer. Due to different crystal growth and fabrication techniques the various types of silicon contain a variety of trace impurity elements and structural defects. The two most important criteria in evaluating the various silicon types for solar cell applications are cost and conversion efficiency.
Comprehensive feedback on trainee surgeons’ non-technical skills
Dieckmann, Peter; Beier-Holgersen, Randi; Rosenberg, Jacob; Oestergaard, Doris
2015-01-01
Objectives This study aimed to explore the content of conversations, feedback style, and perceived usefulness of feedback to trainee surgeons when conversations were stimulated by a tool for assessing surgeons’ non-technical skills. Methods Trainee surgeons and their supervisors used the Non-Technical Skills for Surgeons in Denmark tool to stimulate feedback conversations. Audio recordings of post-operation feedback conversations were collected. Trainees and supervisors provided questionnaire responses on the usefulness and comprehensiveness of the feedback. The feedback conversations were qualitatively analyzed for content and feedback style. Usefulness was investigated using a scale from 1 to 5 and written comments were qualitatively analyzed. Results Six trainees and six supervisors participated in eight feedback conversations. Eighty questionnaires (response rate 83 percent) were collected from 13 trainees and 12 supervisors. Conversations lasted median eight (2-15) minutes. Supervisors used the elements and categories in the tool to structure the content of the conversations. Supervisors tended to talk about the trainees’ actions and their own frames rather than attempting to understand the trainees’ perceptions. Supervisors and trainees welcomed the feedback opportunity and agreed that the conversations were useful and comprehensive. Conclusions The content of the feedback conversations reflected the contents of the tool and the feedback was considered useful and comprehensive. However, supervisors talked primarily about their own frames, so in order for the feedback to reach its full potential, supervisors may benefit from training techniques to stimulate a deeper reflection among trainees. PMID:25602262
Richelle, M; Darimont, C; Piguet-Welsch, C; Fay, L B
2004-01-01
This paper presents a high-throughput method for the simultaneous determination of deuterium and oxygen-18 (18O) enrichment of water samples isolated from blood. This analytical method enables rapid and simple determination of these enrichments of microgram quantities of water. Water is converted into hydrogen and carbon monoxide gases by the use of a high-temperature conversion elemental analyzer (TC-EA), that are then transferred on-line into the isotope ratio mass spectrometer. Accuracy determined with the standard light Antartic precipitation (SLAP) and Greenland ice sheet precipitation (GISP) is reliable for deuterium and 18O enrichments. The range of linearity is from 0 up to 0.09 atom percent excess (APE, i.e. -78 up to 5725 delta per mil (dpm)) for deuterium enrichment and from 0 up to 0.17 APE (-11 up to 890 dpm) for 18O enrichment. Memory effects do exist but can be avoided by analyzing the biological samples in quintuplet. This method allows the determination of 1440 samples per week, i.e. 288 biological samples per week. Copyright 2004 John Wiley & Sons, Ltd.
47 CFR 51.316 - Conversion of unbundled network elements and services.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 47 Telecommunication 3 2013-10-01 2013-10-01 false Conversion of unbundled network elements and... § 51.316 Conversion of unbundled network elements and services. (a) Upon request, an incumbent LEC... element, or combination of unbundled network elements, that is available to the requesting...
47 CFR 51.316 - Conversion of unbundled network elements and services.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 47 Telecommunication 3 2014-10-01 2014-10-01 false Conversion of unbundled network elements and... § 51.316 Conversion of unbundled network elements and services. (a) Upon request, an incumbent LEC... element, or combination of unbundled network elements, that is available to the requesting...
47 CFR 51.316 - Conversion of unbundled network elements and services.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 47 Telecommunication 3 2012-10-01 2012-10-01 false Conversion of unbundled network elements and... § 51.316 Conversion of unbundled network elements and services. (a) Upon request, an incumbent LEC... element, or combination of unbundled network elements, that is available to the requesting...
Readerbench: Automated Evaluation of Collaboration Based on Cohesion and Dialogism
ERIC Educational Resources Information Center
Dascalu, Mihai; Trausan-Matu, Stefan; McNamara, Danielle S.; Dessus, Philippe
2015-01-01
As Computer-Supported Collaborative Learning (CSCL) gains a broader usage, the need for automated tools capable of supporting tutors in the time-consuming process of analyzing conversations becomes more pressing. Moreover, collaboration, which presumes the intertwining of ideas or points of view among participants, is a central element of dialogue…
Coplen, Tyler B.; Qi, Haiping
2016-01-01
The hydrogen isotopic composition (δ2HVSMOW-SLAP) of USGS42 and USGS43 human hair stable isotopic reference materials, normalized to the VSMOW (Vienna-Standard Mean Ocean Water)–SLAP (Standard Light Antarctic Precipitation) scale, was originally determined with a high temperature conversion technique using an elemental analyzer (TC/EA) with a glassy carbon tube and glassy carbon filling and analysis by isotope-ratio mass spectrometer (IRMS). However, the TC/EA IRMS method can produce inaccurate δ2HVSMOW-SLAPresults when analyzing nitrogen-bearing organic substances owing to the formation of hydrogen cyanide (HCN), leading to non-quantitative conversion of a sample into molecular hydrogen (H2) for IRMS analysis. A single-oven, chromium-filled, elemental analyzer (Cr-EA) coupled to an IRMS substantially improves the measurement quality and reliability of hydrogen isotopic analysis of hydrogen- and nitrogen-bearing organic material because hot chromium scavenges all reactive elements except hydrogen. USGS42 and USGS43 human hair isotopic reference materials have been analyzed with the Cr-EA IRMS method, and the δ2HVSMOW-SLAP values of their non-exchangeable hydrogen fractions have been revised:where mUr = 0.001 = ‰. On average, these revised δ2HVSMOW-SLAP values are 5.7 mUr more positive than those previously measured. It is critical that readers pay attention to the δ2HVSMOW-SLAP of isotopic reference materials in publications as they may need to adjust the δ2HVSMOW–SLAP measurement results of human hair in previous publications to ensure all results are on the same isotope-delta scale.
Coplen, Tyler B; Qi, Haiping
2016-09-01
The hydrogen isotopic composition (δ(2)HVSMOW-SLAP) of USGS42 and USGS43 human hair stable isotopic reference materials, normalized to the VSMOW (Vienna-Standard Mean Ocean Water)-SLAP (Standard Light Antarctic Precipitation) scale, was originally determined with a high temperature conversion technique using an elemental analyzer (TC/EA) with a glassy carbon tube and glassy carbon filling and analysis by isotope-ratio mass spectrometer (IRMS). However, the TC/EA IRMS method can produce inaccurate δ(2)HVSMOW-SLAP results when analyzing nitrogen-bearing organic substances owing to the formation of hydrogen cyanide (HCN), leading to non-quantitative conversion of a sample into molecular hydrogen (H2) for IRMS analysis. A single-oven, chromium-filled, elemental analyzer (Cr-EA) coupled to an IRMS substantially improves the measurement quality and reliability of hydrogen isotopic analysis of hydrogen- and nitrogen-bearing organic material because hot chromium scavenges all reactive elements except hydrogen. USGS42 and USGS43 human hair isotopic reference materials have been analyzed with the Cr-EA IRMS method, and the δ(2)HVSMOW-SLAP values of their non-exchangeable hydrogen fractions have been revised: [Formula: see text] [Formula: see text] where mUr=0.001=‰. On average, these revised δ(2)HVSMOW-SLAP values are 5.7mUr more positive than those previously measured. It is critical that readers pay attention to the δ(2)HVSMOW-SLAP of isotopic reference materials in publications as they may need to adjust the δ(2)HVSMOW-SLAP measurement results of human hair in previous publications to ensure all results are on the same isotope-delta scale. Published by Elsevier Ireland Ltd.
Principle research on a single mass piezoelectric six-degrees-of-freedom accelerometer.
Liu, Jun; Li, Min; Qin, Lan; Liu, Jingcheng
2013-08-16
A signal mass piezoelectric six-degrees-of-freedom (six-DOF) accelerometer is put forward in response to the need for health monitoring of the dynamic vibration characteristics of high grade digitally controlled machine tools. The operating principle of the piezoelectric six-degrees-of-freedom accelerometer is analyzed, and its structure model is constructed. The numerical simulation model (finite element model) of the six axis accelerometer is established. Piezoelectric quartz is chosen for the acceleration sensing element and conversion element, and its static sensitivity, static coupling interference and dynamic natural frequency, dynamic cross coupling are analyzed by ANSYS software. Research results show that the piezoelectric six-DOF accelerometer has advantages of simple and rational structure, correct sensing principle and mathematic model, good linearity, high rigidity, and theoretical natural frequency is more than 25 kHz, no nonlinear cross coupling and no complex decoupling work.
Principle Research on a Single Mass Piezoelectric Six-Degrees-of-Freedom Accelerometer
Liu, Jun; Li, Min; Qin, Lan; Liu, Jingcheng
2013-01-01
A signal mass piezoelectric six-degrees-of-freedom (six-DOF) accelerometer is put forward in response to the need for health monitoring of the dynamic vibration characteristics of high grade digitally controlled machine tools. The operating principle of the piezoelectric six-degrees-of-freedom accelerometer is analyzed, and its structure model is constructed. The numerical simulation model (finite element model) of the six axis accelerometer is established. Piezoelectric quartz is chosen for the acceleration sensing element and conversion element, and its static sensitivity, static coupling interference and dynamic natural frequency, dynamic cross coupling are analyzed by ANSYS software. Research results show that the piezoelectric six-DOF accelerometer has advantages of simple and rational structure, correct sensing principle and mathematic model, good linearity, high rigidity, and theoretical natural frequency is more than 25 kHz, no nonlinear cross coupling and no complex decoupling work. PMID:23959243
47 CFR 51.316 - Conversion of unbundled network elements and services.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 47 Telecommunication 3 2011-10-01 2011-10-01 false Conversion of unbundled network elements and... § 51.316 Conversion of unbundled network elements and services. (a) Upon request, an incumbent LEC shall convert a wholesale service, or group of wholesale services, to the equivalent unbundled network...
47 CFR 51.316 - Conversion of unbundled network elements and services.
Code of Federal Regulations, 2010 CFR
2010-10-01
... 47 Telecommunication 3 2010-10-01 2010-10-01 false Conversion of unbundled network elements and... § 51.316 Conversion of unbundled network elements and services. (a) Upon request, an incumbent LEC shall convert a wholesale service, or group of wholesale services, to the equivalent unbundled network...
Systematic Characterization and Comparative Analysis of the Rabbit Immunoglobulin Repertoire
Lavinder, Jason J.; Hoi, Kam Hon; Reddy, Sai T.; Wine, Yariv; Georgiou, George
2014-01-01
Rabbits have been used extensively as a model system for the elucidation of the mechanism of immunoglobulin diversification and for the production of antibodies. We employed Next Generation Sequencing to analyze Ig germline V and J gene usage, CDR3 length and amino acid composition, and gene conversion frequencies within the functional (transcribed) IgG repertoire of the New Zealand white rabbit (Oryctolagus cuniculus). Several previously unannotated rabbit heavy chain variable (VH) and light chain variable (VL) germline elements were deduced bioinformatically using multidimensional scaling and k-means clustering methods. We estimated the gene conversion frequency in the rabbit at 23% of IgG sequences with a mean gene conversion tract length of 59±36 bp. Sequencing and gene conversion analysis of the chicken, human, and mouse repertoires revealed that gene conversion occurs much more extensively in the chicken (frequency 70%, tract length 79±57 bp), was observed to a small, yet statistically significant extent in humans, but was virtually absent in mice. PMID:24978027
Systems and methods for reducing transient voltage spikes in matrix converters
Kajouke, Lateef A.; Perisic, Milun; Ransom, Ray M.
2013-06-11
Systems and methods are provided for delivering energy using an energy conversion module that includes one or more switching elements. An exemplary electrical system comprises a DC interface, an AC interface, an isolation module, a first conversion module between the DC interface and the isolation module, and a second conversion module between the AC interface and the isolation module. A control module is configured to operate the first conversion module to provide an injection current to the second conversion module to reduce a magnitude of a current through a switching element of the second conversion module before opening the switching element.
Gehre, Matthias; Renpenning, Julian; Gilevska, Tetyana; Qi, Haiping; Coplen, Tyler B.; Meijer, Harro A.J.; Brand, Willi A.; Schimmelmann, Arndt
2015-01-01
The high temperature conversion (HTC) technique using an elemental analyzer with a glassy carbon tube and filling (temperature conversion/elemental analysis, TC/EA) is a widely used method for hydrogen isotopic analysis of water and many solid and liquid organic samples with analysis by isotope-ratio mass spectrometry (IRMS). However, the TC/EA IRMS method may produce inaccurate δ2H results, with values deviating by more than 20 mUr (milliurey = 0.001 = 1‰) from the true value for some materials. We show that a single-oven, chromium-filled elemental analyzer coupled to an IRMS substantially improves the measurement quality and reliability for hydrogen isotopic compositions of organic substances (Cr-EA method). Hot chromium maximizes the yield of molecular hydrogen in a helium carrier gas by irreversibly and quantitatively scavenging all reactive elements except hydrogen. In contrast, under TC/EA conditions, heteroelements like nitrogen or chlorine (and other halogens) can form hydrogen cyanide (HCN) or hydrogen chloride (HCl) and this can cause isotopic fractionation. The Cr-EA technique thus expands the analytical possibilities for on-line hydrogen-isotope measurements of organic samples significantly. This method yielded reproducibility values (1-sigma) for δ2H measurements on water and caffeine samples of better than 1.0 and 0.5 mUr, respectively. To overcome handling problems with water as the principal calibration anchor for hydrogen isotopic measurements, we have employed an effective and simple strategy using reference waters or other liquids sealed in silver-tube segments. These crimped silver tubes can be employed in both the Cr-EA and TC/EA techniques. They simplify considerably the normalization of hydrogen-isotope measurement data to the VSMOW-SLAP (Vienna Standard Mean Ocean Water-Standard Light Antarctic Precipitation) scale, and their use improves accuracy of the data by eliminating evaporative loss and associated isotopic fractionation while handling water as a bulk sample. The calibration of organic samples, commonly having high δ2H values, will benefit from the availability of suitably 2H-enriched reference waters, extending the VSMOW-SLAP scale above zero.
A microwave piezoelectric transducer with a microstrip exciter system
NASA Astrophysics Data System (ADS)
Grigor'ev, M. A.; Petrov, V. V.; Tolstikov, A. V.
1990-12-01
The paper considers a microwave electroacoustic bulk-wave transducer with a microstrip exciter system. The operation of the device is analyzed on the basis of the dependence of the dimensionless radiation resistance on the phase advance in the piezoelectric. The optimal wave resistance, the area of the piezoelectric element, the length of the short-circuited section, the SWR, and the conversion factor are determined.
Conversion of Clinical Data from the NABISH 1 and 2 into FITBIR
2015-10-01
Research (FITBIR) Informatics System. Data sets from the National Acute Brain Injury Study: Hypothermia (NABISH) projects will be reviewed, analyzed, and...Keywords and Acronyms: Common Data Elements (CDEs) FITBIR – the Federal Interagency Traumatic Brain Injury Research Informatics System Form...NOTES 14. ABSTRACT This project will prepare a related group of legacy data sets for addition to the Federal Interagency Traumatic Brain Injury
A low complexity, low spur digital IF conversion circuit for high-fidelity GNSS signal playback
NASA Astrophysics Data System (ADS)
Su, Fei; Ying, Rendong
2016-01-01
A low complexity high efficiency and low spur digital intermediate frequency (IF) conversion circuit is discussed in the paper. This circuit is key element in high-fidelity GNSS signal playback instrument. We analyze the spur performance of a finite state machine (FSM) based numerically controlled oscillators (NCO), by optimization of the control algorithm, a FSM based NCO with 3 quantization stage can achieves 65dB SFDR in the range of the seventh harmonic. Compare with traditional lookup table based NCO design with the same Spurious Free Dynamic Range (SFDR) performance, the logic resource require to implemented the NCO is reduced to 1/3. The proposed design method can be extended to the IF conversion system with good SFDR in the range of higher harmonic components by increasing the quantization stage.
Format conversion between CAD data and GIS data based on ArcGIS
NASA Astrophysics Data System (ADS)
Xie, Qingqing; Wei, Bo; Zhang, Kailin; Wang, Zhichao
2015-12-01
To make full use of the data resources and realize a sharing for the different types of data in different industries, a method of format conversion between CAD data and GIS data based on ArcGIS was proposed. To keep the integrity of the converted data, some key steps to process CAD data before conversion were made in AutoCAD. For examples, deleting unnecessary elements such as title, border and legend avoided the appearance of unnecessary elements after conversion, as layering data again by a national standard avoided the different types of elements to appear in a same layer after conversion. In ArcGIS, converting CAD data to GIS data was executed by the correspondence of graphic element classification between AutoCAD and ArcGIS. In addition, an empty geographic database and feature set was required to create in ArcGIS for storing the text data of CAD data. The experimental results show that the proposed method avoids a large amount of editing work in data conversion and maintains the integrity of spatial data and attribute data between before and after conversion.
Lott, Michael J; Howa, John D; Chesson, Lesley A; Ehleringer, James R
2015-08-15
Elemental analyzer systems generate N(2) and CO(2) for elemental composition and isotope ratio measurements. As quantitative conversion of nitrogen in some materials (i.e., nitrate salts and nitro-organic compounds) is difficult, this study tests a recently published method - thermal decomposition without the addition of O(2) - for the analysis of these materials. Elemental analyzer/isotope ratio mass spectrometry (EA/IRMS) was used to compare the traditional combustion method (CM) and the thermal decomposition method (TDM), where additional O(2) is eliminated from the reaction. The comparisons used organic and inorganic materials with oxidized and/or reduced nitrogen and included ureas, nitrate salts, ammonium sulfate, nitro esters, and nitramines. Previous TDM applications were limited to nitrate salts and ammonium sulfate. The measurement precision and accuracy were compared to determine the effectiveness of converting materials containing different fractions of oxidized nitrogen into N(2). The δ(13) C(VPDB) values were not meaningfully different when measured via CM or TDM, allowing for the analysis of multiple elements in one sample. For materials containing oxidized nitrogen, (15) N measurements made using thermal decomposition were more precise than those made using combustion. The precision was similar between the methods for materials containing reduced nitrogen. The %N values were closer to theoretical when measured by TDM than by CM. The δ(15) N(AIR) values of purchased nitrate salts and ureas were nearer to the known values when analyzed using thermal decomposition than using combustion. The thermal decomposition method addresses insufficient recovery of nitrogen during elemental analysis in a variety of organic and inorganic materials. Its implementation requires relatively few changes to the elemental analyzer. Using TDM, it is possible to directly calibrate certain organic materials to international nitrate isotope reference materials without off-line preparation. Copyright © 2015 John Wiley & Sons, Ltd.
History Detectives Visit NASA Goddard Space Flight Center
2017-12-08
The name of the instrument is X-Ray Photoelecton Spectrometer (acronymed XPS); the lab is in the Materials Engineering Branch and aptly titled the X-Ray Photoelectron Spectrometry Lab. XPS is a non-destructive surface analysis technique that provides an elemental composition of the surface. It is capable of detecting any element with the exception of hydrogen and helium. In the picture, I am analyzing a piece of the film that the History Detectives believed was from the Echo II Project. I was looking for the presence of chromium, which would help confirm that the exterior of the film had a chromium conversion coating. PHOTO CREDIT: NASA/Debbie Mccallum
Hybrid chip-on-board LED module with patterned encapsulation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Soer, Wouter Anthon; Helbing, Rene; Huang, Guan
Different wavelength conversion materials, or different concentrations of a wavelength conversion material are used to encapsulate the light emitting elements of different colors of a hybrid light emitting module. In an embodiment of this invention, second light emitting elements (170) of a particular color are encapsulated with a transparent second encapsulant (120;420;520), while first light emitting elements (160) of a different color are encapsulated with a wavelength conversion first encapsulant (110;410;510). In another embodiment of this invention, a particular second set of second and third light emitting elements (170,580) of different colors is encapsulated with a different encapsulant than anothermore » first set of first light emitting elements (160).« less
Systems and methods for deactivating a matrix converter
Ransom, Ray M.
2013-04-02
Systems and methods are provided for deactivating a matrix conversion module. An electrical system comprises an alternating current (AC) interface, a matrix conversion module coupled to the AC interface, an inductive element coupled between the AC interface and the matrix conversion module, and a control module. The control module is coupled to the matrix conversion module, and in response to a shutdown condition, the control module is configured to operate the matrix conversion module to deactivate the first conversion module when a magnitude of a current through the inductive element is less than a threshold value.
Accident Analysis for the NIST Research Reactor Before and After Fuel Conversion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Baek J.; Diamond D.; Cuadra, A.
Postulated accidents have been analyzed for the 20 MW D2O-moderated research reactor (NBSR) at the National Institute of Standards and Technology (NIST). The analysis has been carried out for the present core, which contains high enriched uranium (HEU) fuel and for a proposed equilibrium core with low enriched uranium (LEU) fuel. The analyses employ state-of-the-art calculational methods. Three-dimensional Monte Carlo neutron transport calculations were performed with the MCNPX code to determine homogenized fuel compositions in the lower and upper halves of each fuel element and to determine the resulting neutronic properties of the core. The accident analysis employed a modelmore » of the primary loop with the RELAP5 code. The model includes the primary pumps, shutdown pumps outlet valves, heat exchanger, fuel elements, and flow channels for both the six inner and twenty-four outer fuel elements. Evaluations were performed for the following accidents: (1) control rod withdrawal startup accident, (2) maximum reactivity insertion accident, (3) loss-of-flow accident resulting from loss of electrical power with an assumption of failure of shutdown cooling pumps, (4) loss-of-flow accident resulting from a primary pump seizure, and (5) loss-of-flow accident resulting from inadvertent throttling of a flow control valve. In addition, natural circulation cooling at low power operation was analyzed. The analysis shows that the conversion will not lead to significant changes in the safety analysis and the calculated minimum critical heat flux ratio and maximum clad temperature assure that there is adequate margin to fuel failure.« less
Smith, Michael A; Clayman, Marla L; Frader, Joel; Arenson, Melanie; Haber-Barker, Natalie; Ryan, Claire; Emanuel, Linda; Michelson, Kelly
2018-06-19
Little is known about how decision-making conversations occur during pediatric intensive care unit (PICU) family conferences (FCs). Describe the decision-making process and implementation of shared decision making (SDM) during PICU FCs. Observational study. University-based tertiary care PICU, including 31 parents and 94 PICU healthcare professionals involved in FCs. We recorded, transcribed, and analyzed 14 PICU FCs involving decision-making discussions. We used a modified grounded theory and content analysis approach to explore the use of traditionally described stages of decision making (DM) (information exchange, deliberation, and determining a plan). We also identified the presence or absence of predefined SDM elements. DM involved the following modified stages: information exchange; information-oriented deliberation; plan-oriented deliberation; and determining a plan. Conversations progressed through stages in a nonlinear manner. For the main decision discussed, all conferences included a presentation of the clinical issues, treatment alternatives, and uncertainty. A minority of FCs included assessing the family's understanding (21%), assessing the family's need for input from others (28%), exploring the family's desired decision-making role (35%), and eliciting the family's opinion (42%). In the FCs studied, we found that DM is a nonlinear process. We also found that several SDM elements that could provide information about parents' perspectives and needs did not always occur, identifying areas for process improvement.
Compensation for electrical converter nonlinearities
Perisic, Milun; Ransom, Ray M; Kajouke, Lateef A
2013-11-19
Systems and methods are provided for delivering energy from an input interface to an output interface. An electrical system includes an input interface, an output interface, an energy conversion module between the input interface and the output interface, an inductive element between the input interface and the energy conversion module, and a control module. The control module determines a compensated duty cycle control value for operating the energy conversion module to produce a desired voltage at the output interface and operates the energy conversion module to deliver energy to the output interface with a duty cycle that is influenced by the compensated duty cycle control value. The compensated duty cycle control value is influenced by the current through the inductive element and accounts for voltage across the switching elements of the energy conversion module.
Gehre, Matthias; Renpenning, Julian; Geilmann, Heike; Qi, Haiping; Coplen, Tyler B; Kümmel, Steffen; Ivdra, Natalija; Brand, Willi A; Schimmelmann, Arndt
2017-03-30
Accurate hydrogen isotopic analysis of halogen- and sulfur-bearing organics has not been possible with traditional high-temperature conversion (HTC) because the formation of hydrogen-bearing reaction products other than molecular hydrogen (H 2 ) is responsible for non-quantitative H 2 yields and possible hydrogen isotopic fractionation. Our previously introduced, new chromium-based EA-Cr/HTC-IRMS (Elemental Analyzer-Chromium/High-Temperature Conversion Isotope Ratio Mass Spectrometry) technique focused primarily on nitrogen-bearing compounds. Several technical and analytical issues concerning halogen- and sulfur-bearing samples, however, remained unresolved and required further refinement of the reactor systems. The EA-Cr/HTC reactor was substantially modified for the conversion of halogen- and sulfur-bearing samples. The performance of the novel conversion setup for solid and liquid samples was monitored and optimized using a simultaneously operating dual-detection system of IRMS and ion trap MS. The method with several variants in the reactor, including the addition of manganese metal chips, was evaluated in three laboratories using EA-Cr/HTC-IRMS (on-line method) and compared with traditional uranium-reduction-based conversion combined with manual dual-inlet IRMS analysis (off-line method) in one laboratory. The modified EA-Cr/HTC reactor setup showed an overall H 2 -recovery of more than 96% for all halogen- and sulfur-bearing organic compounds. All results were successfully normalized via two-point calibration with VSMOW-SLAP reference waters. Precise and accurate hydrogen isotopic analysis was achieved for a variety of organics containing F-, Cl-, Br-, I-, and S-bearing heteroelements. The robust nature of the on-line EA-Cr/HTC technique was demonstrated by a series of 196 consecutive measurements with a single reactor filling. The optimized EA-Cr/HTC reactor design can be implemented in existing analytical equipment using commercially available material and is universally applicable for both heteroelement-bearing and heteroelement-free organic-compound classes. The sensitivity and simplicity of the on-line EA-Cr/HTC-IRMS technique provide a much needed tool for routine hydrogen-isotope source tracing of organic contaminants in the environment. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.
Assistant for Analyzing Tropical-Rain-Mapping Radar Data
NASA Technical Reports Server (NTRS)
James, Mark
2006-01-01
A document is defined that describes an approach for a Tropical Rain Mapping Radar Data System (TDS). TDS is composed of software and hardware elements incorporating a two-frequency spaceborne radar system for measuring tropical precipitation. The TDS would be used primarily in generating data products for scientific investigations. The most novel part of the TDS would be expert-system software to aid in the selection of algorithms for converting raw radar-return data into such primary observables as rain rate, path-integrated rain rate, and surface backscatter. The expert-system approach would address the issue that selection of algorithms for processing the data requires a significant amount of preprocessing, non-intuitive reasoning, and heuristic application, making it infeasible, in many cases, to select the proper algorithm in real time. In the TDS, tentative selections would be made to enable conversions in real time. The expert system would remove straightforwardly convertible data from further consideration, and would examine ambiguous data, performing analysis in depth to determine which algorithms to select. Conversions performed by these algorithms, presumed to be correct, would be compared with the corresponding real-time conversions. Incorrect real-time conversions would be updated using the correct conversions.
Conversion of the trace elements Zn, Cd, and Pb in the combustion of near-Moscow coals
DOE Office of Scientific and Technical Information (OSTI.GOV)
E.V. Samuilov; L.N. Lebedeva; L.S. Pokrovskaya
A model for the conversion of trace elements in the combustion of near-Moscow coals based on a complex approach combining the capabilities of geochemistry, chemical thermodynamics, phase analysis, and chemical kinetics is proposed. The conversion of the trace elements Zn, Cd, and Pb as the constituents of near-Moscow coal in the flow of coal combustion products along the line of the P-59 boiler at the Ryazanskaya Thermal Power Plant was calculated. Experimental data were used in the development of the model and in calculations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dunn, Floyd E.; Hu, Lin-wen; Wilson, Erik
The STAT code was written to automate many of the steady-state thermal hydraulic safety calculations for the MIT research reactor, both for conversion of the reactor from high enrichment uranium fuel to low enrichment uranium fuel and for future fuel re-loads after the conversion. A Monte-Carlo statistical propagation approach is used to treat uncertainties in important parameters in the analysis. These safety calculations are ultimately intended to protect against high fuel plate temperatures due to critical heat flux or departure from nucleate boiling or onset of flow instability; but additional margin is obtained by basing the limiting safety settings onmore » avoiding onset of nucleate boiling. STAT7 can simultaneously analyze all of the axial nodes of all of the fuel plates and all of the coolant channels for one stripe of a fuel element. The stripes run the length of the fuel, from the bottom to the top. Power splits are calculated for each axial node of each plate to determine how much of the power goes out each face of the plate. By running STAT7 multiple times, full core analysis has been performed by analyzing the margin to ONB for each axial node of each stripe of each plate of each element in the core.« less
Systems and methods for commutating inductor current using a matrix converter
Ransom, Ray M; Kajouke, Lateef A; Perisic, Milun
2012-10-16
Systems and methods are provided for delivering current using a matrix converter in a vehicle. An electrical system comprises an AC interface, a first conversion module coupled to the AC interface, an inductive element coupled between the AC interface and the first conversion module, and a control module coupled to the first conversion module. The control module is configured to operate the first conversion module in a bidirectional operating mode to commutate current bidirectionally. When a magnitude of the current through the inductive element is greater than a first threshold value, the control module operates the conversion module in a unidirectional operating mode, wherein current is commutated unidirectionally.
Wen, Xianyu; Jeong, Seorin; Kim, Younghoon; Bae, Jeong Mo; Cho, Nam Yun; Kim, Jung Ho; Kang, Gyeong Hoon
2017-01-01
Formalin-fixed, paraffin-embedded (FFPE) tissues are important resources for profiling DNA methylation changes and for studying a variety of diseases. However, formalin fixation introduces inter-strand crosslinking, which might cause incomplete bisulfite conversion of unmethylated cytosines, which might lead to falsely elevated measurements of methylation levels in pyrosequencing assays. Long interspersed nucleotide element-1 (LINE-1) is a major constituent of repetitive transposable DNA elements, and its methylation is referred to correlates with global DNA methylation. To identify whether formalin fixation might impact the measured values of methylation in LINE-1 repetitive elements and whether prolonged heat-induced denaturation of DNA might reduce the artificial increases in measured values caused by formalin fixation, we analyzed paired fresh-frozen (FF) and FFPE xenograft tissue samples for their methylation levels in LINE-1 using a pyrosequencing assay. To further confirm the effect of a heating step in the measurement of LINE-1 or single gene methylation levels, we analyzed FFPE tissue samples of gastric cancer and colorectal cancer for their methylation status in LINE-1 and eight single genes, respectively. Formalin fixation led to an increase in the measured values of LINE-1 methylation regardless of the duration of fixation. Prolonged heating of the DNA at 95 °C for 30 min before bisulfite conversion was found (1) to decrease the discrepancy in the measured values between the paired FF and FFPE tissue samples, (2) to decrease the standard deviation of the measured value of LINE-1 methylation levels in FFPE tissue samples of gastric cancer, and (3) to improve the performance in the measurement of single gene methylation levels in FFPE tissue samples of colorectal cancer. Formalin fixation leads to artificial increases in the measured values of LINE-1 methylation, and the application of prolonged heating of DNA samples decreases the discrepancy in the measured values of LINE-1 methylation between paired FF and FFPE tissue samples. The application of prolonged heating of DNA samples improves bisulfite conversion-based measurement of LINE-1 or single gene methylation levels in FFPE tissue samples.
Conversion of electromagnetic energy in Z-pinch process of single planar wire arrays at 1.5 MA
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liangping, Wang; Mo, Li; Juanjuan, Han
The electromagnetic energy conversion in the Z-pinch process of single planar wire arrays was studied on Qiangguang generator (1.5 MA, 100 ns). Electrical diagnostics were established to monitor the voltage of the cathode-anode gap and the load current for calculating the electromagnetic energy. Lumped-element circuit model of wire arrays was employed to analyze the electromagnetic energy conversion. Inductance as well as resistance of a wire array during the Z-pinch process was also investigated. Experimental data indicate that the electromagnetic energy is mainly converted to magnetic energy and kinetic energy and ohmic heating energy can be neglected before the final stagnation. Themore » kinetic energy can be responsible for the x-ray radiation before the peak power. After the stagnation, the electromagnetic energy coupled by the load continues increasing and the resistance of the load achieves its maximum of 0.6–1.0 Ω in about 10–20 ns.« less
ERIC Educational Resources Information Center
Hooper, Kristina
1982-01-01
Provides the rationale for considering communication in a graphic domain and suggests a specific goal for designing work stations which provide graphic capabilities in educational settings. The central element of this recommendation is the "pictorial conversation", a highly interactive exchange that includes pictures as the central elements.…
More Than One Way to Debrief: A Critical Review of Healthcare Simulation Debriefing Methods.
Sawyer, Taylor; Eppich, Walter; Brett-Fleegler, Marisa; Grant, Vincent; Cheng, Adam
2016-06-01
Debriefing is a critical component in the process of learning through healthcare simulation. This critical review examines the timing, facilitation, conversational structures, and process elements used in healthcare simulation debriefing. Debriefing occurs either after (postevent) or during (within-event) the simulation. The debriefing conversation can be guided by either a facilitator (facilitator-guided) or the simulation participants themselves (self-guided). Postevent facilitator-guided debriefing may incorporate several conversational structures. These conversational structures break the debriefing discussion into a series of 3 or more phases to help organize the debriefing and ensure the conversation proceeds in an orderly manner. Debriefing process elements are an array of techniques to optimize reflective experience and maximize the impact of debriefing. These are divided here into the following 3 categories: essential elements, conversational techniques/educational strategies, and debriefing adjuncts. This review provides both novice and advanced simulation educators with an overview of various methods of conducting healthcare simulation debriefing. Future research will investigate which debriefing methods are best for which contexts and for whom, and also explore how lessons from simulation debriefing translate to debriefing in clinical practice.
Charging system with galvanic isolation and multiple operating modes
Kajouke, Lateef A.; Perisic, Milun; Ransom, Ray M.
2013-01-08
Systems and methods are provided for operating a charging system with galvanic isolation adapted for multiple operating modes. A vehicle charging system comprises a DC interface, an AC interface, a first conversion module coupled to the DC interface, and a second conversion module coupled to the AC interface. An isolation module is coupled between the first conversion module and the second conversion module. The isolation module comprises a transformer and a switching element coupled between the transformer and the second conversion module. The transformer and the switching element are cooperatively configured for a plurality of operating modes, wherein each operating mode of the plurality of operating modes corresponds to a respective turns ratio of the transformer.
Cipriani, Federica; Ratti, Francesca; Fiorentini, Guido; Catena, Marco; Paganelli, Michele; Aldrighetti, Luca
2018-03-28
Previous abdominal surgery has traditionally been considered an additional element of difficulty to later laparoscopic procedures. The aim of the study is to analyze the effect of previous surgery on the feasibility and safety of laparoscopic liver resection (LLR), and its role as a risk factor for conversion. After matching, 349 LLR in patients known for previous abdominal surgery (PS group) were compared with 349 LLR on patients with a virgin abdomen (NPS group). Subgroup analysis included 161 patients with previous upper abdominal surgery (UPS subgroup). Feasibility and safety were evaluated in terms of conversion rate, reasons for conversion and outcomes, and risk factors for conversion assessed via uni/multivariable analysis. Conversion rate was 9.4%, and higher for PS patients compared with NPS patients (13.7% versus 5.1%, P = .021). Difficult adhesiolysis resulted the commonest reason for conversion in PS group (5.7%). However, operative time (P = .840), blood loss (P = .270), transfusion (P = .650), morbidity rate (P = .578), hospital stay (P = .780), and R1 rate (P = .130) were comparable between PS and NPS group. Subgroup analysis confirmed higher conversion rates for UPS patients (23%) compared with both NPS (P = .015) and PS patients (P = .041). Previous surgery emerged as independent risk factor for conversion (P = .033), alongside the postero-superior location and major hepatectomy. LLR are feasible in case of previous surgery and proved to be safe and maintain the benefits of LLR carried out in standard settings. However, a history of surgery should be considered a risk factor for conversion.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Laurens, Lieve M; Olstad-Thompson, Jessica L; Templeton, David W
Accurately determining protein content is important in the valorization of algal biomass in food, feed, and fuel markets, where these values are used for component balance calculations. Conversion of elemental nitrogen to protein is a well-accepted and widely practiced method, but depends on developing an applicable nitrogen-to-protein conversion factor. The methodology reported here covers the quantitative assessment of the total nitrogen content of algal biomass and a description of the methodology that underpins the accurate de novo calculation of a dedicated nitrogen-to-protein conversion factor.
NASA Astrophysics Data System (ADS)
Dai, Hongyu; Li, Lee; Peng, Ming-yang; Xiong, Jiaming; Wu, Haibo; Yu, Bin
2017-12-01
In order to reduce the effect of residual carbon on the insulation performance, after the GW-hundreds kiloampere graphite-electrode switch turning on, the chemical kinetics of the carbon-oxygen reaction is analyzed. The capacitive pulsed experimental circuit is used to reconstruct the actual condition of high power and high current discharge. The carbon-oxygen reaction efficiency is analyzed using a Fourier transform infrared spectrometer and a flue gas analyzer. The research shows that the gas products include NOX, O3, CH4, and COX. Through the quantitative analysis, the conversion efficiency of COX increases with the augment of the accumulated transferred charge, and the change law of the CO generation efficiency has an extreme value. With the corresponding calculation and the observation of the scanning electron microscope, it is found that most of the carbon consumed from the graphite electrodes is converted to amorphous elemental carbon, and the insufficiency of the carbon-oxygen reaction leads to the problem of carbon residue, for 20%-45% of elemental carbon is not oxidized. The size of amorphous elemental carbon is about several micrometers to tens micrometers by the analysis of metallographic microscope. In the condition of compressed air, changing the amount of transferred charge is helpful to improve the carbon-oxygen reaction efficiency and inhibit the problem of carbon residue.
Jakubczak, J. L.; Zenni, M. K.; Woodruff, R. C.; Eickbush, T. H.
1992-01-01
R1 and R2 are distantly related non-long terminal repeat retrotransposable elements each of which inserts into a specific site in the 28S rRNA genes of most insects. We have analyzed aspects of R1 and R2 abundance and sequence variation in 27 geographical isolates of Drosophila melanogaster. The fraction of 28S rRNA genes containing these elements varied greatly between strains, 17-67% for R1 elements and 2-28% for R2 elements. The total percentage of the rDNA repeats inserted ranged from 32 to 77%. The fraction of the rDNA repeats that contained both of these elements suggested that R1 and R2 exhibit neither an inhibition of nor preference for insertion into a 28S gene already containing the other type of element. Based on the conservation of restriction sites in the elements of all strains, and sequence analysis of individual elements from three strains, nucleotide divergence is very low for R1 and R2 elements within or between strains (<0.6%). This sequence uniformity is the expected result of the forces of concerted evolution (unequal crossovers and gene conversion) which act on the rRNA genes themselves. Evidence for the role of retrotransposition in the turnover of R1 and R2 was obtained by using naturally occurring 5' length polymorphisms of the elements as markers for independent transposition events. The pattern of these different length 5' truncations of R1 and R2 was found to be diverse and unique to most strains analyzed. Because recombination can only, with time, amplify or eliminate those length variants already present, the diversity found in each strain suggests that retrotransposition has played a critical role in maintaining these elements in the rDNA repeats of D. melanogaster. PMID:1317313
Rectenna session: Micro aspects. [energy conversion
NASA Technical Reports Server (NTRS)
Gutmann, R. J.
1980-01-01
Two micro aspects of the rectenna design are addressed: evaluation of the degradation in net rectenna RF to DC conversion efficiency due to power density variations across the rectenna (power combining analysis) and design of Yagi-Uda receiving elements to reduce rectenna cost by decreasing the number of conversion circuits (directional receiving elements). The first of these micro aspects involves resolving a fundamental question of efficiency potential with a rectenna, while the second involves a design modification with a large potential cost saving.
Sulfide catalysts for reducing SO2 to elemental sulfur
Jin, Yun; Yu, Qiquan; Chang, Shih-Ger
2001-01-01
A highly efficient sulfide catalyst for reducing sulfur dioxide to elemental sulfur, which maximizes the selectivity of elemental sulfur over byproducts and has a high conversion efficiency. Various feed stream contaminants, such as water vapor are well tolerated. Additionally, hydrogen, carbon monoxide, or hydrogen sulfides can be employed as the reducing gases while maintaining high conversion efficiency. This allows a much wider range of uses and higher level of feed stream contaminants than prior art catalysts.
Dirbeba, Meheretu Jaleta; Brink, Anders; DeMartini, Nikolai; Zevenhoven, Maria; Hupa, Mikko
2017-06-01
In this work, potential for thermochemical conversion of biomass residues from an integrated sugar-ethanol process and the fate of ash and ash-forming elements in the process are presented. Ash, ash-forming elements, and energy flows in the process were determined using mass balances and analyses of eight different biomass samples for ash contents, elemental compositions, and heating values. The results show that the ash content increases from the sugarcane to the final residue, vinasse. The cane straw, which is left in the field, contains one-third of the energy and 25% of the K and Cl while the vinasse contains 2% of the energy and 40% of the K and Cl in the cane. K and Cl in biomass fuels cause corrosion and fouling problems in boilers and gasifiers. Over 85% of these elements in the straw are water soluble indicating that water leaching would improve it for utilization in thermochemical conversion. Copyright © 2017 Elsevier Ltd. All rights reserved.
Radiation detector having a multiplicity of individual detecting elements
Whetten, Nathan R.; Kelley, John E.
1985-01-01
A radiation detector has a plurality of detector collection element arrays immersed in a radiation-to-electron conversion medium. Each array contains a multiplicity of coplanar detector elements radially disposed with respect to one of a plurality of positions which at least one radiation source can assume. Each detector collector array is utilized only when a source is operative at the associated source position, negating the necessity for a multi-element detector to be moved with respect to an object to be examined. A novel housing provides the required containment of a high-pressure gas conversion medium.
Discharging a DC bus capacitor of an electrical converter system
Kajouke, Lateef A; Perisic, Milun; Ransom, Ray M
2014-10-14
A system and method of discharging a bus capacitor of a bidirectional matrix converter of a vehicle are presented here. The method begins by electrically shorting the AC interface of the converter after an AC energy source is disconnected from the AC interface. The method continues by arranging a plurality of switching elements of a second energy conversion module into a discharge configuration to establish an electrical current path from a first terminal of an isolation module, through an inductive element, and to a second terminal of the isolation module. The method also modulates a plurality of switching elements of a first energy conversion module, while maintaining the discharge configuration of the second energy conversion module, to at least partially discharge a DC bus capacitor.
DOT National Transportation Integrated Search
1997-01-01
Conversion of a general-purpose freeway into a high-occupancy-vehicle (HOV) lane is an alternative to infrastructure addition for HOV system implementation. Research indicates that lane conversion is feasible technically if sufficient HOV usage and m...
Healing and Conversion in New Religious Movements in Africa: Elements of an Indigenous Epistemology.
ERIC Educational Resources Information Center
Sanneh, Lamin
In this analysis of healing and conversion as two of the most notable and persistent traits of the new religious movements in Africa, healing is described as an indigenous religious category within the context of conversion as a modern permutation of African religion. Religious conversion is most strikingly represented in societies where the…
Friction Modifier Using Adherent Metallic Multilayered or Mixed Element Layer Conversion Coatings
NASA Technical Reports Server (NTRS)
Schramm, Harry F. (Inventor); Defalco, Francis G. (Inventor); Starks, Lloyd L., Sr. (Inventor)
2013-01-01
A process for creating conversion coatings and spin, drawing, and extrusion finishes for surfaces, wherein the conversion coatings and spin, drawing, and extrusion finishes contain potassium, phosphorus, nitrogen, and one or more non-alkaline metals and/or one or more metalloids. The process comprises forming an aqueous solution of water, phosphoric acid or sulfuric acid, ammonium hydroxide, an alkali metal hydroxide, and one or more non-alkaline metals and/or one or more metalloids. The aqueous solution forms an anti-friction multilayer conversion and/or mixed element coating or a spin, drawing, and extrusion finish on a surface when applied to the surface, either directly without the use of applied external electromotive force, or as an additive in lubricating fluids.
Gene conversion as a secondary mechanism of short interspersed element (SINE) evolution
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kass, D.H.; Batzer, M.A.; Deininger, P.L.
The Alu repetitive family of short interspersed elements (SINEs) in primates can be subdivided into distinct subfamilies by specific diagnostic nucleotide changes. The older subfamilies are generally very abundant, while the younger subfamilies have fewer copies. Some of the youngest Alu elements are absent in the orthologous loci of nonhuman primates, indicative of recent retroposition events, the primary mode of SINE evolutions. PCR analysis of one young Alu subfamily (Sb2) member found in the low-density lipoprotein receptor gene apparently revealed the presence of this element in the green monkey, orangutan, gorilla, and chimpanzee genomes, as well as the human genome.more » However, sequence analysis of these genomes revealed a highly mutated, older, primate-specific Alu element was present at this position in the nonhuman primates. Comparison of the flanking DNA sequences upstream of this Alu insertion corresponded to evolution expected for standard primate phylogeny, but comparison of the Alu repeat sequences revealed that the human element departed from this phylogeny. The change in the human sequence apparently occurred by a gene conversion event only within the Alu element itself, converting it from one of the oldest to one of the youngest Alu subfamilies. Although gene conversions of Alu elements are clearly very rare, this finding shows that such events can occur and contribute to specific cases of SINE subfamily evolution.« less
Digital receiver study and implementation
NASA Technical Reports Server (NTRS)
Fogle, D. A.; Lee, G. M.; Massey, J. C.
1972-01-01
Computer software was developed which makes it possible to use any general purpose computer with A/D conversion capability as a PSK receiver for low data rate telemetry processing. Carrier tracking, bit synchronization, and matched filter detection are all performed digitally. To aid in the implementation of optimum computer processors, a study of general digital processing techniques was performed which emphasized various techniques for digitizing general analog systems. In particular, the phase-locked loop was extensively analyzed as a typical non-linear communication element. Bayesian estimation techniques for PSK demodulation were studied. A hardware implementation of the digital Costas loop was developed.
Electrochemical Impedance Imaging via the Distribution of Diffusion Times
NASA Astrophysics Data System (ADS)
Song, Juhyun; Bazant, Martin Z.
2018-03-01
We develop a mathematical framework to analyze electrochemical impedance spectra in terms of a distribution of diffusion times (DDT) for a parallel array of random finite-length Warburg (diffusion) or Gerischer (reaction-diffusion) circuit elements. A robust DDT inversion method is presented based on complex nonlinear least squares regression with Tikhonov regularization and illustrated for three cases of nanostructured electrodes for energy conversion: (i) a carbon nanotube supercapacitor, (ii) a silicon nanowire Li-ion battery, and (iii) a porous-carbon vanadium flow battery. The results demonstrate the feasibility of nondestructive "impedance imaging" to infer microstructural statistics of random, heterogeneous materials.
A system for automatic evaluation of simulation software
NASA Technical Reports Server (NTRS)
Ryan, J. P.; Hodges, B. C.
1976-01-01
Within the field of computer software, simulation and verification are complementary processes. Simulation methods can be used to verify software by performing variable range analysis. More general verification procedures, such as those described in this paper, can be implicitly, viewed as attempts at modeling the end-product software. From software requirement methodology, each component of the verification system has some element of simulation to it. Conversely, general verification procedures can be used to analyze simulation software. A dynamic analyzer is described which can be used to obtain properly scaled variables for an analog simulation, which is first digitally simulated. In a similar way, it is thought that the other system components and indeed the whole system itself have the potential of being effectively used in a simulation environment.
Polonsky, William H; Capehorn, Matthew; Belton, Anne; Down, Susan; Alzaid, Aus; Gamerman, Victoria; Nagel, Friedericke; Lee, Jisoo; Edelman, Steven
2017-05-01
To investigate patient experiences during the diagnosis of type 2 diabetes mellitus (T2DM), focusing on how physician-patient communication at diagnosis influences patients' psychosocial stress and subsequent self-management and outcomes. We surveyed adults with T2DM in 26 countries in a large cross-national study of physician-patient communication during early T2DM treatment (IntroDia®). The self-report questionnaire assessed retrospectively patient experiences during diagnosis conversations (focusing on 43 possible conversational elements, and communication quality) and potential effects on patient-reported outcomes. Data from 3628 people with T2DM who had been prescribed oral treatment at diagnosis were analysed. Exploratory factor analyses of the conversational elements yielded four coherent, meaningful factors: Encouraging (Cronbach's α=0.86); Collaborative (α=0.88); Recommending Other Resources (α=0.75); and Discouraging (α=0.72). Patient-perceived communication quality (PPCQ) at diagnosis was positively associated with Encouraging (β=+1.764, p<0.001) and Collaborative (β=+0.347, p<0.001), negatively associated with Discouraging (β=-1.181, p<0.001) and not associated with Recommending Other Resources (β=+0.087, p=0.096), using a stable path model. PPCQ was associated with less current diabetes distress, greater current well-being and better current self-care. Conversation elements comprising factors associated with better PPCQ (Encouraging and Collaborative) were recalled more frequently by patients than elements associated with poor PPCQ (Discouraging). Better physician-patient communication at T2DM diagnosis may contribute to subsequent greater patient well-being and self-care, and may be enhanced by greater physician use of Collaborative and Encouraging conversation elements. Copyright © 2017 Elsevier B.V. All rights reserved.
SAFARI-1: Achieving conversion to LEU - A local challenge
DOE Office of Scientific and Technical Information (OSTI.GOV)
Piani, C.S.B.
2008-07-15
Two years have passed since the South African Department of Minerals and Energy authorised the conversion from High Enriched Uranium (HEU) to Low Enriched Uranium (LEU) of the South African Research Reactor (SAFARI-1) and the associated fuel manufacturing at Pelindaba. The scheduling, as originally proposed, allowed approximately three years for the full conversion of the reactor, anticipating simultaneous manufacturing ability from the fuel production plant. Due to technical difficulties experienced in the conversion of the local manufacturing plant from HEU (UAl alloy) to LEU (U Silicide) and the uncertainty as to costing and scheduling of such an achievement, the conversionmore » of SAFARI-1 based on local supply has been allocated a lower priority. The acquisition in mid-2006 of 2 LEU silicide elements of SA design, manufactured by AREVA- CERCA and irradiated as test elements in SAFARI-1 to burn-ups of {approx}65% each; was successfully accomplished within 9 cycles of irradiation each. Furthermore, four 'Hybrid' elements (AREVA-CERCA plates assembled locally at Pelindaba) are ready for irradiation and have received regulatory authorisation to load. This will enable the SAFARI-1 conversion program to continue systematically according to an agreed schedule. This paper will trace the developments of the above and reflect the current status and the rescheduled conversion phases of the reactor according to latest expectations. (author)« less
Guide to Software Conversion Management. [Final Report.
ERIC Educational Resources Information Center
Skall, M., Ed.
Based mainly on interviews conducted at 14 federal agencies that had completed or were involved in software conversion projects, this publication provides guidelines for the entire process of software conversion. This is defined as the transformation, without functional change, of computer programs or data elements to permit their use on a…
24 CFR 972.218 - Conversion assessment components.
Code of Federal Regulations, 2014 CFR
2014-04-01
... assessment contains five elements, as described below: (a) Cost analysis. A PHA must conduct a cost analysis... part. (b) Analysis of the market value. (1) A PHA must have an independent appraisal conducted to... analysis of market value of the development in the conversion assessment must be provided in the conversion...
24 CFR 972.218 - Conversion assessment components.
Code of Federal Regulations, 2012 CFR
2012-04-01
... assessment contains five elements, as described below: (a) Cost analysis. A PHA must conduct a cost analysis... part. (b) Analysis of the market value. (1) A PHA must have an independent appraisal conducted to... analysis of market value of the development in the conversion assessment must be provided in the conversion...
24 CFR 972.218 - Conversion assessment components.
Code of Federal Regulations, 2013 CFR
2013-04-01
... assessment contains five elements, as described below: (a) Cost analysis. A PHA must conduct a cost analysis... part. (b) Analysis of the market value. (1) A PHA must have an independent appraisal conducted to... analysis of market value of the development in the conversion assessment must be provided in the conversion...
Kagan, Aura; Winckel, Joanne; Black, Sandra; Duchan, Judith Felson; Simmons-Mackie, Nina; Square, Paula
2004-01-01
Conversation partners of individuals with aphasia, including health care professionals, families, and others, play a role that is as important for communication as the language disorder suffered by individuals with aphasia. Two complementary measures designed to capture elements of conversation between adults with aphasia and their speaking conversation partners have been developed. The first measure provides an index of the conversation partner's skill in providing conversational support. The second provides an index of the level of participation in conversation by the person with aphasia. This article describes the development of the measures, including preliminary psychometric data, and discusses applications.
An Analysis of Mentoring Conversations with Beginning Teachers: Suggestions and Responses
ERIC Educational Resources Information Center
Strong, Michael; Baron, Wendy
2004-01-01
This study analyzes how mentor teachers make pedagogical suggestions to beginning teachers during mentoring conversations and how beginning teachers respond. Sixty-four conversations between 16 veteran teacher mentors and their beginning teacher proteges are examined and analyzed. The analysis reveals the extreme efforts of mentors to avoid giving…
Rectenna session: Micro aspects
NASA Technical Reports Server (NTRS)
Gutmann, R. J.
1980-01-01
Two micro aspects of rectenna design are discussed: evaluation of the degradation in net rectenna RF to DC conversion efficiency due to power density variations across the rectenna (power combining analysis) and design of Yagi-Uda receiving elements to reduce rectenna cost by decreasing the number of conversion circuits (directional receiving elements). The first of these involves resolving a fundamental question of efficiency potential with a rectenna, while the second involves a design modification with a large potential cost saving.
Magnetic Field Experiment Data Analysis System
NASA Technical Reports Server (NTRS)
Holland, D. B.; Zanetti, L. J.; Suther, L. L.; Potemra, T. A.; Anderson, B. J.
1995-01-01
The Johns Hopkins University Applied Physics Laboratory (JHU/APL) Magnetic Field Experiment Data Analysis System (MFEDAS) has been developed to process and analyze satellite magnetic field experiment data from the TRIAD, MAGSAT, AMPTE/CCE, Viking, Polar BEAR, DMSP, HILAT, UARS, and Freja satellites. The MFEDAS provides extensive data management and analysis capabilities. The system is based on standard data structures and a standard user interface. The MFEDAS has two major elements: (1) a set of satellite unique telemetry processing programs for uniform and rapid conversion of the raw data to a standard format and (2) the program Magplot which has file handling, data analysis, and data display sections. This system is an example of software reuse, allowing new data sets and software extensions to be added in a cost effective and timely manner. Future additions to the system will include the addition of standard format file import routines, modification of the display routines to use a commercial graphics package based on X-Window protocols, and a generic utility for telemetry data access and conversion.
Li, Yuzhong; Tong, Huiling; Zhuo, Yuqun; Wang, Shujuan; Xu, Xuchang
2006-12-15
Sulfur dioxide (SO2) and trace elements are all pollutants derived from coal combustion. This study relates to the simultaneous removal of SO2 and trace selenium dioxide (SeO2) from flue gas by calcium oxide (CaO) adsorption in the moderate temperature range, especially the effect of SO2 presence on selenium capture. Experiments performed on a thermogravimetric analyzer (TGA) can reach the following conclusions. When the CaO conversion is relatively low and the reaction rate is controlled by chemical kinetics, the SO2 presence does not affect the selenium capture. When the CaO conversion is very high and the reaction rate is controlled by product layer diffusion, the SO2 presence and the product layer diffusion resistance jointly reduce the selenium capture. On the basis of the kinetics study, a method to estimate the trace selenium removal efficiency using kinetic parameters and the sulfur removal efficiency is developed.
NASA Astrophysics Data System (ADS)
Beecken, B. P.; Fossum, E. R.
1996-07-01
Standard statistical theory is used to calculate how the accuracy of a conversion-gain measurement depends on the number of samples. During the development of a theoretical basis for this calculation, a model is developed that predicts how the noise levels from different elements of an ideal detector array are distributed. The model can also be used to determine what dependence the accuracy of measured noise has on the size of the sample. These features have been confirmed by experiment, thus enhancing the credibility of the method for calculating the uncertainty of a measured conversion gain. detector-array uniformity, charge coupled device, active pixel sensor.
Electrochemical Impedance Imaging via the Distribution of Diffusion Times.
Song, Juhyun; Bazant, Martin Z
2018-03-16
We develop a mathematical framework to analyze electrochemical impedance spectra in terms of a distribution of diffusion times (DDT) for a parallel array of random finite-length Warburg (diffusion) or Gerischer (reaction-diffusion) circuit elements. A robust DDT inversion method is presented based on complex nonlinear least squares regression with Tikhonov regularization and illustrated for three cases of nanostructured electrodes for energy conversion: (i) a carbon nanotube supercapacitor, (ii) a silicon nanowire Li-ion battery, and (iii) a porous-carbon vanadium flow battery. The results demonstrate the feasibility of nondestructive "impedance imaging" to infer microstructural statistics of random, heterogeneous materials.
Design and analysis of a field modulated magnetic screw for artificial heart
NASA Astrophysics Data System (ADS)
Ling, Zhijian; Ji, Jinghua; Wang, Fangqun; Bian, Fangfang
2017-05-01
This paper proposes a new electromechanical energy conversion system, called Field Modulated Magnetic Screw (FMMS) as a high force density linear actuator for artificial heart. This device is based on the concept of magnetic screw and linear magnetic gear. The proposed FMMS consists of three parts with the outer and inner carrying the radially magnetized helically permanent-magnet (PM), and the intermediate having a set of helically ferromagnetic pole pieces, which modulate the magnetic fields produced by the PMs. The configuration of the newly designed FMMS is presented and its electromagnetic performances are analyzed by using the finite-element analysis, verifying the advantages of the proposed structure.
Zumwalt, L.R.
1961-08-01
Fuel elements having a solid core of fissionable material encased in a cladding material are described. A conversion material is provided within the cladding to react with the fission products to form stable, relatively non- volatile compounds thereby minimizing the migration of the fission products into the coolant. The conversion material is preferably a metallic fluoride, such as lead difluoride, and may be in the form of a coating on the fuel core or interior of the cladding, or dispersed within the fuel core. (AEC)
Revised Mulliken Electronegativities I. Calculation and Conversion to Pauling Units.
ERIC Educational Resources Information Center
Bratsch, Steven G.
1988-01-01
Discusses a revision and extension of the Mulliken electronegativity scale to consider 50 elements. Describes the calculation of valence-state promotion energies and Mulliken atomic electronegativities and the conversion of Mulliken electronegativities to Pauling units. (CW)
Booth, Richard G
2015-02-01
The use of social media platforms like Twitter within/for nursing education has become more common in recent years. Regardless, it is unclear how nursing students use technology like Twitter during the course of their nursing education. The aim of this paper was to explore how nursing students describe elements of their nursing education via the social media platform, Twitter. Tweets about nursing courses, classes, and clinical were collected in October 2011 and analyzed for themes. Overall, 498 tweets were collected over a collective six day period, and 189 tweets were codified into five thematic representations. Nursing students were found to discuss a variety of elements related to their nursing education, including events and situations they perceived to be positive or exciting. Stress and annoyance messaging was also noted as a salient theme expressed by nursing students when describing their education. Vulgarity and derogative messaging targeting elements of nursing education (including courses, students, and faculty) were found in a subset of tweets. The majority of the tweets collected in this study contained random discursive conversations regarding nursing education, including information seeking requests and declarative statements about temporal events. The findings of this study point to a need for educators to explore aspects surrounding eProfessionalism within nursing education. Similarly, this paper also highlights the growing requirement for nursing educators to learn more about how social media is being used by nursing students within/for their education, in order to better develop learning and networking opportunities for students. Without this, nursing education may miss a significant opportunity to help shape students' professional use of social media technology like Twitter. Copyright © 2014 Elsevier Ltd. All rights reserved.
Biochar elemental composition and factors influencing nutrient retention
USDA-ARS?s Scientific Manuscript database
Biochar is the carbonaceous solid byproduct of the thermochemical conversion of a carbon-bearing organic material, commonly high in cellulose, hemicelluloses, or lignin content, for the purposes of carbon sequestration and storage. More specifically, the thermal conversion process known as pyrolysi...
Puthillath, Padmakumar; Galan, Jose M; Ren, Baiyang; Lissenden, Cliff J; Rose, Joseph L
2013-05-01
Ultrasonic guided wave inspection of structures containing adhesively bonded joints requires an understanding of the interaction of guided waves with geometric and material discontinuities or transitions in the waveguide. Such interactions result in mode conversion with energy being partitioned among the reflected and transmitted modes. The step transition between an aluminum layer and an aluminum-adhesive-aluminum multi-layer waveguide is analyzed as a model structure. Dispersion analysis enables assessment of (i) synchronism through dispersion curve overlap and (ii) wavestructure correlation. Mode-pairs in the multi-layer waveguide are defined relative to a prescribed mode in a single layer as being synchronized and having nearly perfect wavestructure matching. Only a limited number of mode-pairs exist, and each has a unique frequency range. A hybrid model based on semi-analytical finite elements and the normal mode expansion is implemented to assess mode conversion at a step transition in a waveguide. The model results indicate that synchronism and wavestructure matching is associated with energy transfer through the step transition, and that the energy of an incident wave mode in a single layer is transmitted almost entirely to the associated mode-pair, where one exists. This analysis guides the selection of incident modes that convert into transmitted modes and improve adhesive joint inspection with ultrasonic guided waves.
ECUT (Energy Conversion and Utilization Technologies) program: Biocatalysis Project
NASA Technical Reports Server (NTRS)
1988-01-01
Fiscal year 1987 research activities and accomplishments for the Biocatalysis Project of the U.S. Department of Energy, Energy Conversion and Utilization Technologies (ECUT) Division are presented. The project's technical activities were organized into three work elements. The Molecular Modeling and Applied Genetics work element includes modeling and simulation studies to verify a dynamic model of the enzyme carboxypeptidase; plasmid stabilization by chromosomal integration; growth and stability characteristics of plasmid-containing cells; and determination of optional production parameters for hyper-production of polyphenol oxidase. The Bioprocess Engineering work element supports efforts in novel bioreactor concepts that are likely to lead to substantially higher levels of reactor productivity, product yields, and lower separation energetics. The Bioprocess Design and Assessment work element attempts to develop procedures (via user-friendly computer software) for assessing the economics and energetics of a given biocatalyst process.
Structure of Children's Narratives.
ERIC Educational Resources Information Center
Menig-Peterson, Carole L.; McCabe, Allyssa
This analysis of the structure of children's narratives deals with material gathered from 96 children, aged 3 1/2 to 9 1/2 years, in conversations about events in which they were personally involved. Elements of the narratives and the structural relationship of these elements are examined. Three elements are discerned: (1) chronological…
NASA Astrophysics Data System (ADS)
Savenkov, G. G.; Kardo-Sysoev, A. F.; Zegrya, A. G.; Os'kin, I. A.; Bragin, V. A.; Zegrya, G. G.
2017-10-01
The first findings concerning the initiation of explosive conversions in energy-saturated nanoporous silicon-based compounds via the electrical explosion of a semiconductor bridge are presented. The obtained results indicate that the energy parameters of an explosive conversion depend on the mass of a combustible agent—namely, nanoporous silicon—and the silicon-doping type.
Surveys of research in the Chemistry Division, Argonne National Laboratory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grazis, B.M.
1992-01-01
Research reports are presented on reactive intermediates in condensed phase (radiation chemistry, photochemistry), electron transfer and energy conversion, photosynthesis and solar energy conversion, metal cluster chemistry, chemical dynamics in gas phase, photoionization-photoelectrons, characterization and reactivity of coal and coal macerals, premium coal sample program, chemical separations, heavy elements coordination chemistry, heavy elements photophysics/photochemistry, f-electron interactions, radiation chemistry of high-level wastes (gas generation in waste tanks), ultrafast molecular electronic devices, and nuclear medicine. Separate abstracts have been prepared. Accelerator activites and computer system/network services are also reported.
Surveys of research in the Chemistry Division, Argonne National Laboratory
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grazis, B.M.
1992-11-01
Research reports are presented on reactive intermediates in condensed phase (radiation chemistry, photochemistry), electron transfer and energy conversion, photosynthesis and solar energy conversion, metal cluster chemistry, chemical dynamics in gas phase, photoionization-photoelectrons, characterization and reactivity of coal and coal macerals, premium coal sample program, chemical separations, heavy elements coordination chemistry, heavy elements photophysics/photochemistry, f-electron interactions, radiation chemistry of high-level wastes (gas generation in waste tanks), ultrafast molecular electronic devices, and nuclear medicine. Separate abstracts have been prepared. Accelerator activites and computer system/network services are also reported.
A Power Conversion Concept for the Jupiter Icy Moons Orbiter
NASA Technical Reports Server (NTRS)
Mason, Lee S.
2003-01-01
The Jupiter Icy Moons Orbiter (JIMO) is a bold new mission under development by the Office of Space Science at NASA Headquarters. ITMO is examining the potential of Nuclear Electric Propulsion (NEP) technology to efficiently deliver scientific payloads to three Jovian moons: Callisto, Ganymede, and Europa. A critical element of the NEP vehicle is the reactor power system, consisting of the nuclear reactor, power conversion, heat rejection, and power management and distribution (PMAD). The emphasis of this paper is on the non-nuclear elements of the reactor power system.
24 CFR 965.404 - Order of conversion.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 24 Housing and Urban Development 4 2011-04-01 2011-04-01 false Order of conversion. 965.404...-Owned Projects § 965.404 Order of conversion. Conversions to individually metered utility service shall... be analyzed both for the installation of checkmeters and for conversion to retail service. (d) Low...
24 CFR 965.404 - Order of conversion.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 24 Housing and Urban Development 4 2010-04-01 2010-04-01 false Order of conversion. 965.404...-Owned Projects § 965.404 Order of conversion. Conversions to individually metered utility service shall... be analyzed both for the installation of checkmeters and for conversion to retail service. (d) Low...
Brooksbank, W.A. Jr.; Leddicotte, G.W.; Strain, J.E.; Hendon, H.H. Jr.
1961-11-14
A means was developed for continuously computing and indicating the isotopic assay of a process solution and for automatically controlling the process output of isotope separation equipment to provide a continuous output of the desired isotopic ratio. A counter tube is surrounded with a sample to be analyzed so that the tube is exactly in the center of the sample. A source of fast neutrons is provided and is spaced from the sample. The neutrons from the source are thermalized by causing them to pass through a neutron moderator, and the neutrons are allowed to diffuse radially through the sample to actuate the counter. A reference counter in a known sample of pure solvent is also actuated by the thermal neutrons from the neutron source. The number of neutrons which actuate the detectors is a function of a concentration of the elements in solution and their neutron absorption cross sections. The pulses produced by the detectors responsive to each neu tron passing therethrough are amplified and counted. The respective times required to accumulate a selected number of counts are measured by associated timing devices. The concentration of a particular element in solution may be determined by utilizing the following relation: T2/Ti = BCR, where B is a constant proportional to the absorption cross sections, T2 is the time of count collection for the unknown solution, Ti is the time of count collection for the pure solvent, R is the isotopic ratlo, and C is the molar concentration of the element to be determined. Knowing the slope constant B for any element and when the chemical concentration is known, the isotopic concentration may be readily determined, and conversely when the isotopic ratio is known, the chemical concentrations may be determined. (AEC)
Defect induced guided waves mode conversion
NASA Astrophysics Data System (ADS)
Wandowski, Tomasz; Kudela, Pawel; Malinowski, Pawel; Ostachowicz, Wieslaw
2016-04-01
This paper deals with analysis of guided waves mode conversion phenomenon in fiber reinforced composite materials. Mode conversion phenomenon may take place when propagating elastic guided waves interact with discontinuities in the composite waveguide. The examples of such discontinuities are sudden thickness change or delamination between layers in composite material. In this paper, analysis of mode conversion phenomenon is based on full wave-field signals. In the full wave-field approach signals representing propagation of elastic waves are gathered from dense mesh of points that span over investigated area of composite part. This allow to animate the guided wave propagation. The reported analysis is based on signals resulting from numerical calculations and experimental measurements. In both cases defect in the form of delamination is considered. In the case of numerical research, Spectral Element Method (SEM) is utilized, in which a mesh is composed of 3D elements. Numerical model includes also piezoelectric transducer. Full wave-field experimental measurements are conducted by using piezoelectric transducer for guided wave excitation and Scanning Laser Doppler Vibrometer (SLDV) for sensing.
Woo, Je-Min; Seo, Jung Yoon; Kim, Hyunuk; Lee, Dong-Ho; Park, Young Cheol; Yi, Chang-Keun; Park, Yeong Seong; Moon, Jong-Ho
2018-06-01
The influence of ultrasonication treatment on the catalytic performance of CuY zeolite catalysts was investigated for the liquid-phase oxidative carbonylation of methanol to dimethyl carbonate (DMC). The deammoniation method of NH 4 Y into HY zeolites was optimized and characterized by elemental analyzer, derivative thermogravimetry, Brunauer-Emmett-Teller (BET) analyzer, and powder X-ray diffractometry, revealing that the HY zeolite deammoniated at 400 °C presented the highest surface area, complete ammonium/proton ion exchange, and no structure collapse, rendering it the best support from all the prepared zeolites. CuY zeolites were prepared via aqueous phase ion exchange with the aid of ultrasonication. Upon ultrasonication, the Cu + active centers were uniformly dispersed in the Y zeolites, penetrating the core of the zeolite particles in a very short time. In addition to enhancing the Cu dispersity, the ultrasonication treatment influenced the BET surface area, acid amount, Cu + /Cu 2+ ratio, and also had a relatively small impact on the Cu loading. Consequently, adequate exposure to ultrasonication was able to increase the conversion rate of methanol into dimethyl carbonate up to 11.4% with a comparable DMC selectivity of 23.7%. This methanol conversion is 2.65 times higher than that obtained without the ultrasonication treatment. Copyright © 2018 Elsevier B.V. All rights reserved.
On Universal Elements, and Conversion Procedures to and from Position and Velocity
1989-07-01
Abstract. An element set is advocated that is familiar (in traditional terms), and yet applicable to all types of orbit without loss of ,: ... accuracy...A Set of Universally Applicable Elements We seek to define a set of universally applicable elements for motion in unperturbed orbits about a centre...respect to 4 , and denote it by , If a particular element set can be chosen that covers every type of orbit , then in principle we regard these elements
NASA Astrophysics Data System (ADS)
Schmidt, Alexander; Weyer, Stefan; John, Timm; Brey, Gerhard P.
2009-01-01
The depleted mantle and the continental crust are generally thought to balance the budget of refractory and lithophile elements of the Bulk Silicate Earth (BSE), resulting in complementary trace element patterns. However, the two high field strength elements (HFSE) niobium and tantalum appear to contradict this mass balance. All reservoirs of the silicate Earth exhibit subchondritic Nb/Ta ratios, possibly as a result of Nb depletion. In this study a series of nineteen orogenic MORB-type eclogites from different localities was analyzed to determine their HFSE concentrations and to contribute to the question of whether subducted oceanic crust could form a hidden reservoir to account for the mass imbalance of Nb/Ta between BSE and the chondritic reservoir. Concentrations of HFSE were analyzed with isotope dilution (ID) techniques. Additionally, LA-ICPMS analyses of clinopyroxene, garnet and rutile have been performed. Rutile is by far the major host for Nb and Ta in all analyzed eclogites. However, many rutiles revealed zoning in Nb/Ta ratios, with cores being higher than rims. Accordingly, in situ analyses of rutiles have to be evaluated carefully and rutile cores do not necessarily reflect a bulk rock Nb and Ta composition, although over 90% of these elements reside in rutile. The HFSE concentration data in bulk rocks show that the orogenic eclogites have subchondritic Nb/Ta ratios and near chondritic Zr/Hf ratios. The investigated eclogites show neither enrichment of Nb compared to similarly incompatible elements (e.g. La), nor fractionation of Nb/Ta ratios relative to MOR-basalts, the likely precursor of these rocks. This indicates that during the conversion of the oceanic crust to eclogites in most cases, (1) HFSE and REE have similar mobility on average, possibly because both element groups remain in the down going slab, and (2) no significant fractionation of Nb/Ta occurs in subducted oceanic crust. With an average Nb/Ta ratio of 14.2 ± 1.4 (2s.e.), the investigated eclogites cannot balance the differences between BSE and chondrite. Additionally, as their average Nb/Ta is indistinguishable from the Nb/Ta of MORB, they are also an unlikely candidate to balance the potentially small differences in Nb/Ta between the continental crust and the mantle.
Olaison, Anna
2017-02-01
Elder care has undergone a marketization in recent years in which various models for care management have been introduced with the aim of making assessments efficient. This article investigates the effects the care management model has on resource allocation for home care when handling the requests of older persons in the needs assessment process. Sixteen tape-recorded assessment conversations with associated case-file texts were analyzed through discourse analysis. The results show that a managerialist thinking has had a partial impact on the assessment process where the documentation requirements have entailed bureaucratization in terms of the transfer that occurs from talk to text. The findings from the study nevertheless indicate that the assessment conversations have clear elements of an individual-centred perspective in which there is room for a care rational dialogue. This constitutes a welfare policy dilemma today. Providing for older people's requests should be on the basis of quality and an individual-centred perspective and care management has had a contrary effect in which focus is directed instead towards needs assessment and bureaucratic processes.
A novel ZVS high voltage power supply for micro-channel plate photomultiplier tubes
NASA Astrophysics Data System (ADS)
Pei, Chengquan; Tian, Jinshou; Liu, Zhen; Qin, Hong; Wu, Shengli
2017-04-01
A novel resonant high voltage power supply (HVPS) with zero voltage switching (ZVS), to reduce the voltage stress on switching devices and improve conversion efficiency, is proposed. The proposed HVPS includes a drive circuit, a transformer, several voltage multiplying circuits, and a regulator circuit. The HVPS contains several secondary windings that can be precisely regulated. The proposed HVPS performed better than the traditional resistor voltage divider, which requires replacing matching resistors resulting in resistor dispersibility in the Micro-Channel Plate (MCP). The equivalent circuit of the proposed HVPS was established and the operational principle analyzed. The entire switching element can achieve ZVS, which was validated by a simulation and experiments. The properties of this HVPS were tested including minimum power loss (240 mW), maximum power loss (1 W) and conversion efficiency (85%). The results of this research are that the proposed HVPS was suitable for driving the micro-channel plate photomultiplier tube (MCP-PMT). It was therefore adopted to test the MCP-PMT, which will be used in Daya Bay reactor neutrino experiment II in China.
A Novel Oscillating Rectenna for Wireless Microwave Power Transmission
NASA Technical Reports Server (NTRS)
McSpadden, J. O.; Dickinson, R. M.; Fan, L.; Chang, K.
1998-01-01
A new concept for solid state wireless microwave power transmission is presented. A 2.45 GHz rectenna element that was designed for over 85% RF to dc power conversion efficiency has been used to oscillate at 3.3 GHz with an approximate 1% dc to RF conversion efficiency.
ERIC Educational Resources Information Center
Ma, T. S.; Wang, C. Y.
1984-01-01
Presents a literature review on methods used to analyze organic elements. Topic areas include methods for: (1) analyzing carbon, hydrogen, and nitrogen; (2) analyzing oxygen, sulfur, and halogens; (3) analyzing other elements; (4) simultaneously determining several elements; and (5) determing trace elements. (JN)
NASA Astrophysics Data System (ADS)
Bai, Xian-Xu; Zhong, Wei-Min; Zou, Qi; Zhu, An-Ding; Sun, Jun
2018-07-01
Based on the structural design concept of ‘functional integration’, this paper proposes the principle of a power-generated magnetorheological energy absorber with velocity self-sensing capability (PGMREA), which realizes the integration of controllable damping mechanism and mechanical energy-electrical energy conversion mechanism in structure profile and multiple functions in function profile, including controllable damping, power generation and velocity self-sensing. The controllable damping mechanism consists of an annular gap and a ball screw. The annular gap fulfilled with MR fluid that operates in pure shear mode under controllable electromagnetic field. The rotational damping torque generated from the controllable damping mechanism is translated to a linear damping force via the ball screw. The mechanical energy-electrical energy conversion mechanism is realized by the ball screw and a generator composed of a permanent magnet rotor and a generator stator. The ball screw based mechanical energy-electrical energy conversion mechanism converts the mechanical energy of excitations to electrical energy for storage or directly to power the controllable damping mechanism of the PGMREA. The velocity self-sensing capability of the PGMREA is achieved via signal processing using the mechanical energy-electrical energy conversion information. Based on the principle of the proposed PGMREA, the mathematical model of the PGMREA is established, including the damping force, generated power and self-sensing velocity. The electromagnetic circuit of the PGMREA is simulated and verified via a finite element analysis software ANSYS. The developed PGMREA prototype is experimentally tested on a servo-hydraulic testing system. The model-based predicted results and the experimental results are compared and analyzed.
Ash reduction strategies in corn stover facilitated by anatomical and size fractionation
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lacey, Jeffrey A.; Emerson, Rachel M.; Thompson, David N.
There is growing interest internationally to produce fuels from renewable biomass resources. Inorganic components of biomass feedstocks, referred to collectively as ash, damage equipment and decrease yields in thermal conversion processes, and decrease feedstock value for biochemical conversion processes. Decreasing the ash content of feedstocks improves conversion efficiency and lowers process costs. Because physiological ash is unevenly distributed in the plant, mechanical processes can be used to separate fractions of the plant based on ash content. This study focuses on the ash separation that can be achieved by separating corn stover by particle size and anatomical fraction. Baled corn stovermore » was hand-separated into anatomical fractions, ground to <19.1 mm, and size separated using six sieves ranging from 9.5 to 0.150 mm. Size fractions were analyzed for total ash content and ash composition. Particle size distributions observed for the anatomical fractions varied considerably. Cob particles were primarily 2.0 mm or greater, while most of the sheath and husk particles were 2.0 mm and smaller. Particles of leaves greater than 0.6 mm contained the greatest amount of total ash, ranging from approximately 8 to 13% dry weight of the total original material, while the fractions with particles smaller than 0.6 mm contained less than 2% of the total ash of the original material. As a result, based on the overall ash content and the elemental ash, specific anatomical and size fractions can be separated to optimize the feedstocks being delivered to biofuels conversion processes and minimize the need for more expensive ash reduction treatments.« less
Selva, E M; Maderazo, A B; Lahue, R S
1997-12-01
The products of the yeast mismatch repair genes MSH2 and MSH3 participate in the inhibition of genetic recombination between homeologous (divergent) DNA sequences. In strains deficient for these genes, homeologous recombination rates between repeated elements are elevated due to the loss of this inhibition. In this study, the effects of these mutations were further analyzed by quantitation of mitotic homeologous recombinants as crossovers, gene conversions or exceptional events in wild-type, msh2, msh3 and msh2 msh3 mutant strains. When homeologous sequences were present as a direct repeat in one orientation, crossovers and gene conversions were elevated in msh2, msh3 and msh2 msh3 strains. The increases were greater in the msh2 msh3 double mutant than in either single mutant. When the order of the homeologous sequences was reversed, the msh2 mutation again yielded increased rates of crossovers and gene conversions. However, in an msh3 strain, gene conversions occurred at higher levels but interchromosomal crossovers were not increased and intrachromosomal crossovers were reduced relative to wild type. The msh2 msh3 double mutant behaved like the msh2 single mutant in this orientation. Control strains harboring homologous duplications were largely but not entirely unaffected in mutant strains, suggesting specificity for the mismatched intermediates of homeologous recombination. In all strains, very few (< 10%) recombinants could be attributed to exceptional events. These results suggest that MSH2 and MSH3 can function differentially to control homeologous exchanges.
Ash reduction strategies in corn stover facilitated by anatomical and size fractionation
Lacey, Jeffrey A.; Emerson, Rachel M.; Thompson, David N.; ...
2016-04-22
There is growing interest internationally to produce fuels from renewable biomass resources. Inorganic components of biomass feedstocks, referred to collectively as ash, damage equipment and decrease yields in thermal conversion processes, and decrease feedstock value for biochemical conversion processes. Decreasing the ash content of feedstocks improves conversion efficiency and lowers process costs. Because physiological ash is unevenly distributed in the plant, mechanical processes can be used to separate fractions of the plant based on ash content. This study focuses on the ash separation that can be achieved by separating corn stover by particle size and anatomical fraction. Baled corn stovermore » was hand-separated into anatomical fractions, ground to <19.1 mm, and size separated using six sieves ranging from 9.5 to 0.150 mm. Size fractions were analyzed for total ash content and ash composition. Particle size distributions observed for the anatomical fractions varied considerably. Cob particles were primarily 2.0 mm or greater, while most of the sheath and husk particles were 2.0 mm and smaller. Particles of leaves greater than 0.6 mm contained the greatest amount of total ash, ranging from approximately 8 to 13% dry weight of the total original material, while the fractions with particles smaller than 0.6 mm contained less than 2% of the total ash of the original material. As a result, based on the overall ash content and the elemental ash, specific anatomical and size fractions can be separated to optimize the feedstocks being delivered to biofuels conversion processes and minimize the need for more expensive ash reduction treatments.« less
Method and apparatus for optical encoding with compressible imaging
NASA Technical Reports Server (NTRS)
Leviton, Douglas B. (Inventor)
2006-01-01
The present invention presents an optical encoder with increased conversion rates. Improvement in the conversion rate is a result of combining changes in the pattern recognition encoder's scale pattern with an image sensor readout technique which takes full advantage of those changes, and lends itself to operation by modern, high-speed, ultra-compact microprocessors and digital signal processors (DSP) or field programmable gate array (FPGA) logic elements which can process encoder scale images at the highest speeds. Through these improvements, all three components of conversion time (reciprocal conversion rate)--namely exposure time, image readout time, and image processing time--are minimized.
Thermionic energy conversion technology - Present and future
NASA Technical Reports Server (NTRS)
Shimada, K.; Morris, J. F.
1977-01-01
Aerospace and terrestrial applications of thermionic direct energy conversion and advances in direct energy conversion (DEC) technology are surveyed. Electrode materials, the cesium plasma drop (the difference between the barrier index and the collector work function), DEC voltage/current characteristics, conversion efficiency, and operating temperatures are discussed. Attention is centered on nuclear reactor system thermionic DEC devices, for in-core or out-of-core operation. Thermionic fuel elements, the radiation shield, power conditions, and a waste heat rejection system are considered among the thermionic DEC system components. Terrestrial applications include topping power systems in fossil fuel and solar power generation.
Selective current collecting design for spring-type energy harvesters
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kim, Dongjin; Roh, Hee Seok; Kim, Yeontae
2015-01-01
Here we present a high performance spring-type piezoelectric energy harvester that selectively collects current from the inner part of a spring shell. We analyzed themain reason behind the low efficiency of the initial design using finite element models and proposed a selective current collecting design that can considerably improve the electrical conversion efficiency of the energy harvester. We found that the newly designed energy harvester increases the output voltage by 8 times leading to an output power of 2.21 mW under an impulsive load of 2.18 N when compared with the conventional design. We envision that selective current collecting designmore » will be used in spring-based self-powered active sensors and energy scavenging devices.« less
Conversation as a Model of Instructional Interaction
ERIC Educational Resources Information Center
Van Bramer, Joan
2003-01-01
The role of social context and the nature of human interaction provide rich resources for the study of learning and human cognition. In order to understand these elements more fully, it is important to consider the language in use within these contexts. The early intervention Reading Recovery is grounded in the belief that the conversation between…
Satyam Naidu, V; Aghalayam, P; Jayanti, S
2016-06-01
The present study investigates the enhancement of CO2 gasification reactivity of coals due to the presence of catalytic elements in biomass such as K2O, CaO, Na2O and MgO. Co-gasification of three Indian coal chars with two biomass chars has been studied using isothermal thermogravimetric analysis (TGA) in CO2 environment at 900, 1000 and 1100°C. The conversion profiles have been used to establish synergetic or inhibitory effect on coal char reactivity by the presence of catalytic elements in biomass char by comparing the 90% conversion time with and without biomass. It is concluded that both biomasses exhibit synergistic behavior when blended with the three coals with casuarina being more synergetic than empty fruit bunch. Some inhibitory effect has been noted for the high ash coal at the highest temperature with higher 90% conversion time for the blend over pure coal, presumably due to diffusional control of the conversion rate. Copyright © 2016 Elsevier Ltd. All rights reserved.
Tuning the metamagnetism in a metallic helical antiferromagnet
NASA Astrophysics Data System (ADS)
Ma, S. C.; Liu, K.; Ma, C. C.; Ge, Q.; Zhang, J. T.; Hu, Y. F.; Liu, E. K.; Zhong, Z. C.
2017-12-01
The antiferromagnetic (AFM)-ferromagnetic (FM) conversion in martensite was observed in Mn/Ni-substitution upon FM elements, such as Fe or Co, in MnNiGe helical antiferromagnets. Here, we report an AFM-FM conversion and consequently a sharp magnetic-field-driven metamagnetic martensitic transformation from paramagnetic (PM) austenite to FM martensite in the Ni- and Mn-substituted MnNiGe alloys with indium, a non-magnetic and large-sized main group element. Accordingly, a giant magnetocaloric effect such that a twofold increase of the magnetic entropy change in MnNi0.92GeIn0.08 and even a nearly threefold increase in the Mn0.92NiGeIn0.08 alloy is obtained with respect to the MnNiGe0.95In0.05 alloy. The origin of AFM-FM conversion and resultantly sharp magnetic-field-induced PM-FM metamagnetic transformation is discussed based on the first-principles calculations and X-ray absorption spectroscopic results.
Electrocatalytic process for carbon dioxide conversion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Masel, Richard I.; Salehi-Khojin, Amin
2017-01-31
An electrocatalytic process for carbon dioxide conversion includes combining a Catalytically Active Element and Helper Catalyst in the presence of carbon dioxide, allowing a reaction to proceed to produce a reaction product, and applying electrical energy to said reaction to achieve electrochemical conversion of said reactant to said reaction product. The Catalytically Active Element can be a metal in the form of supported or unsupported particles or flakes with an average size between 0.6 nm and 100 nm. the reaction products comprise at least one of CO, HCO.sup.-, H.sub.2CO, (HCO.sub.2).sup.-, H.sub.2CO.sub.2, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup.-, CH.sub.3COOH, C.sub.2H.sub.6, (COOH).sub.2, (COO.sup.-).sub.2,more » and CF.sub.3COOH.« less
Electrocatalytic process for carbon dioxide conversion
DOE Office of Scientific and Technical Information (OSTI.GOV)
Masel, Richard I.; Salehi-Khojin, Amin; Kutz, Robert
An electrocatalytic process for carbon dioxide conversion includes combining a Catalytically Active Element and a Helper Polymer in the presence of carbon dioxide, allowing a reaction to proceed to produce a reaction product, and applying electrical energy to said reaction to achieve electrochemical conversion of said carbon dioxide reactant to said reaction product. The Catalytically Active Element can be a metal in the form of supported or unsupported particles or flakes with an average size between 0.6 nm and 100 nm. The reaction products comprise at least one of CO, HCO.sup.-, H.sub.2CO, (HCO.sub.2).sup.-, H.sub.2CO.sub.2, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup.-, CH.sub.3COOH,more » C.sub.2H.sub.6, (COOH).sub.2, (COO.sup.-).sub.2, and CF.sub.3COOH.« less
Apparatuses and method for converting electromagnetic radiation to direct current
Kotter, Dale K; Novack, Steven D
2014-09-30
An energy conversion device may include a first antenna and a second antenna configured to generate an AC current responsive to incident radiation, at least one stripline, and a rectifier coupled with the at least one stripline along a length of the at least one stripline. An energy conversion device may also include an array of nanoantennas configured to generate an AC current in response to receiving incident radiation. Each nanoantenna of the array includes a pair of resonant elements, and a shared rectifier operably coupled to the pair of resonant elements, the shared rectifier configured to convert the AC current to a DC current. The energy conversion device may further include a bus structure operably coupled with the array of nanoantennas and configured to receive the DC current from the array of nanoantennas and transmit the DC current away from the array of nanoantennas.
"Soul" and "Self": Soviet and American Cultures in Conversation.
ERIC Educational Resources Information Center
Carbaugh, Donal
1993-01-01
Analyzes a particular conversation which invokes Soviet and U.S. cultures, demonstrating how conversation is, at least in part, shaped by cultural systems, and how cultural systems differently employ a generic ritual communicative form. (SR)
Brief Report: A Scale for Rating Conversational Impairment in Autism Spectrum Disorder
ERIC Educational Resources Information Center
de Villiers, Jessica; Fine, Jonathan; Ginsberg, Gary; Vaccarella, Liezanne; Szatmari, Peter
2007-01-01
There are few well-standardized measures of conversational breakdown in Autism Spectrum Disorders (ASD). The study's objective was to develop a scale for measuring pragmatic impairments in conversations of individuals with ASD. We analyzed 46 semi-structured conversations of children and adolescents with high-functioning ASD using a functional…
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-15
... Environmental Impact Statement (EIS) for Proposed Conversion to the F-15 Aircraft for the 144th Fighter Wing... conversion to the F-15 aircraft at the 144th Fighter Wing (144 FW) installation at Fresno-Yosemite... action alternatives analyzed will be a conversion from 18 F-16 PAA to 18 F-15 PAA; or conversion to 24 F...
High Average Power Raman Conversion in Diamond: ’Eyesafe’ Output and Fiber Laser Conversion
2015-06-19
Eyesafe’ output and fiber laser conversion 5a. CONTRACT NUMBER FA2386-12-1-4055 5b. GRANT NUMBER Grant 12RSZ077_124055 5c. PROGRAM ELEMENT...generating 380 W was demonstrated using a 630 W Ybdoped fiber laser system. In each case the performance was unsaturated and limited by the available pump...converter for conventional high power laser technologies including Nd doped lasers and Yb-doped fiber lasers. Diamond’s power handling capability now
NASA Technical Reports Server (NTRS)
Boothe, W. A.; Corman, J. C.; Johnson, G. G.; Cassel, T. A. V.
1976-01-01
Results are presented of an investigation of gasification and clean fuels from coal. Factors discussed include: coal and coal transportation costs; clean liquid and gas fuel process efficiencies and costs; and cost, performance, and environmental intrusion elements of the integrated low-Btu coal gasification system. Cost estimates for the balance-of-plant requirements associated with advanced energy conversion systems utilizing coal or coal-derived fuels are included.
Coplen, Tyler B.; Qi, Haiping
2010-01-01
The δ2HVSMOW–SLAP value of total hydrogen of the international measurement standard NBS 22 oil was determined by a new method of sealing water in silver tubes for use in a thermal conversion elemental analysis (TC/EA) reduction unit. The isotopic fractionation of water due to evaporation is virtually non-existent in this silver-tube method. A new value for the δ2HVSMOW–SLAP of NBS 22 oil, calibrated with isotopic reference waters, was determined to be −116.9 ± 0.8‰ (1σ and n = 31).
Sacred changes: Spiritual conversion and transformation.
Mahoney, Annette; Pargament, Kenneth I
2004-05-01
We use Pargament's (1997) definition of religion-"the search for significance in ways related to the sacred"-as a framework to understand spiritual conversion. Like other life-changing transformations, spiritual conversion alters the destinations that clients perceive to be of greatest importance in life (significance) and the pathways by which clients discover what is most significant in life (search). Unlike other transformative experiences, however, spiritual conversion incorporates the third element of religion, "the sacred," into the content of change. To illustrate these points, we discuss two theological models of spiritual conversion rooted in Christianity: a traditional model based on classic western theology and an alternative model based on feminist theology. We then compare processes of spiritual conversion to nonreligious models of transformation. We also highlight the importance for clinical work of the fit between the context of a client's life and the type of spiritual conversion experienced. Copyright 2004 Wiley Periodicals, Inc.
R & D GTDS SST: Code Flowcharts and Input
1995-01-01
trajectory from a given set of initial conditions Typical output is in the form of a printer le of Cartesian coordinates and Keplerian orbital ... orbiting the Earth The input data specied for an EPHEM run are i Initial elements and epoch ii Orbit generator selection iii Conversion of osculating...discussed ELEMENT sets coordinate system reference central body and rst components of initial state ELEMENT sets the second
Effects of Crimped Fiber Paths on Mixed Mode Delamination Behaviors in Woven Fabric Composites
2016-09-01
continuum finite - element models. Three variations of a plain-woven fabric architecture—each of which had different crimped fiber paths—were considered... Finite - Element Analysis Fracture Mechanics Fracture Toughness Mixed Modes Strain Energy Release Rate 16. SECURITY...polymer FB Fully balanced laminate FEA Finite - element analysis FTCM Fracture toughness conversion mechanism G Shear modulus GI, GII, GIII Mode
Photoluminescence Characteristics of Yag:Ce, Gd Based Phosphors with Different Prehistories
NASA Astrophysics Data System (ADS)
Lisitsyn, V. M.; Soshchin, N. P.; Yang yang, Yu; Stepanov, S. A.; Lisitsyna, L. A.; Tulegenova, A. T.; Abdullin, Kh. A.
2017-09-01
Luminescence characteristics of yttrium-aluminum garnet based phosphor samples differed by their elemental composition and prehistory of synthesis are studied. The morphology, structure, and elemental composition of phosphor samples, their excitation and emission spectra, efficiency of phosphor conversion of chip emission, and kinetics of luminescence decay are measured. The emission characteristics of phosphors are compared with their structural properties and elemental composition.
ERIC Educational Resources Information Center
Weider, D. Lawrence
1993-01-01
Drummond and Hopper's article in this issue, "Back Channels Revisited," is discussed in terms of its ability to elicit contrary responses from different scholars because it incorporates elements of two incommensurate approaches to the study of conversation. Weider sets the stage for subsequent articles in this issue. (11 references) (LB)
Technology for satellite power conversion
NASA Technical Reports Server (NTRS)
Campbell, D. P.; Gouker, M. A.; Summers, C.; Gallagher, J. J.
1984-01-01
Techniques for satellite electromagnetic energy transfer and power conversion at millimeter and infrared wavelengths are discussed. The design requirements for rectenna receiving elements are reviewed for both coherent radiation sources and Earth thermal infrared emission. Potential power transmitters including gyrotrons, free electron lasers, and CO2 lasers are assessed along with the rectification properties of metal-oxide metal diode power converters.
ERIC Educational Resources Information Center
Egan, Bridget A.
2009-01-01
Recent developments in early childhood education in the UK and other parts of Europe have emphasised the importance of dialogue between adults and children. In the UK, the EPPE project paid particular attention to the role of extended child-centred conversations ("sustained shared thinking"--Sylva et al. 2003) as an important element or…
Phenomenology of neutron-antineutron conversion
NASA Astrophysics Data System (ADS)
Gardner, Susan; Yan, Xinshuai
2018-03-01
We consider the possibility of neutron-antineutron (n -n ¯ ) conversion, in which the change of a neutron into an antineutron is mediated by an external source, as can occur in a scattering process. We develop the connections between n -n ¯ conversion and n -n ¯ oscillation, in which a neutron spontaneously transforms into an antineutron, noting that if n -n ¯ oscillation occurs in a theory with baryon number minus lepton number (B-L) violation, then n -n ¯ conversion can occur also. We show how an experimental limit on n -n ¯ conversion could connect concretely to a limit on n -n ¯ oscillation, and vice versa, using effective field theory techniques and baryon matrix elements computed in the MIT bag model.
ERIC Educational Resources Information Center
Auchlin, Antoine
1981-01-01
Examines morphemic markers that signal the opening and closing of discourse units, emphasizing their complexity and their central role for a descriptive model of conversation. Then proceeds to analyze their functions within the overall structure of conversation, classifying them according to their properties and uses. Societe Nouvelle Didier…
Parent-Child Conversations about Literacy: A Longitudinal, Observational Study
ERIC Educational Resources Information Center
Treiman, Rebecca; Decker, Kristina; Robins, Sarah; Ghosh, Dina; Rosales, Nicole
2018-01-01
Conversations about literacy-related matters with parents can help prepare children for formal literacy instruction. We studied these conversations using data gathered from fifty-six US families as they engaged in daily activities at home. Analyzing conversations when children were aged 1;10, 2;6, 3;6, and 4;2, we found that explicit talk about…
Coaching Conversations: The Nature of Talk between a Literacy Coach and Three Teachers
ERIC Educational Resources Information Center
Belcastro, Elizabeth G.
2009-01-01
This descriptive case study examined the nature of talk a literacy coach used during coaching conversations to guide collaborative inquiry to support teachers' needs. The study provided a rich description of the type of talk used in the coach's conversations with three kindergarten classroom teachers by analyzing the content of conversation,…
Savelkoul, Eileen M; Zebrowski, Patricia M; Feldstein, Stanley; Cole-Harding, Shirley
2007-01-01
Coordinated interpersonal timing (CIT) is a measure of "conversational congruence," or "attunement," and refers to the degree to which the temporal aspects of the vocal behaviors of co-conversationalists are correlated over the course of a conversation [Jasnow, M., & Feldstein, S. (1986). Adult-like temporal characteristics of mother-infant vocal interaction. Child Development, 57, 754-761]. In the present study, CIT was examined in a group of children who stutter (CWS), and a matched group of nonstuttering children (CWDNS; children who do not stutter), during conversations with either their mother or father recorded in two separate sessions (i.e., mother-child, father-child). Separate audio signals for both the child and parent (mother or father) were analyzed using AVTA software, which allowed for the quantification of sound and silence patterns in simultaneous speech. Squared cross-correlations (i.e., coefficients of CIT) for the durations of five vocal behavior states were obtained for each subject, through time series regression analysis using lag procedures. Vocal state behaviors within conversational turns included: vocalization, pauses, turn switching pauses, and interruptive and noninterruptive simultaneous speech. Results indicated that CWS and their parents showed mutual influence (i.e., CIT in both directions, child to parent and parent to child, or bi-directional influence) for more vocal state behaviors than did CWDNS and their parents. In addition, the CWS exhibited CIT with their parents for the durations of more vocal state behaviors than did the CWDNS (i.e., unidirectional influence). Findings suggest that children who stutter may be more easily influenced by the subtle timing aspects of conversation. Taken further, some of these children may perceive conversations with their parents as either challenging or difficult because of an element of unpredictability brought into conversations by the production of stuttering, the social skills of the child, and the nature of the parent-child relationship. Consequently, these children may be engaging in more pervasive coordination of the temporal characteristics of their speech to those of their conversational partner, as a mechanism by which to more effectively manage verbal interaction. After reading this paper, the learner will be able to: (1) describe the phenomenon of coordinated interpersonal timing (CIT); (2) summarize research findings in CIT as they apply to the verbal interactions of children and their parents; (3) summarize research findings in parent-stuttering child interaction, especially those related to the temporal aspects of both parent and child conversational speech, and (4) discuss the applicability of the findings from the present study to the treatment of childhood stuttering.
1988-12-01
Conversion of the Geopotential into the Modified Orbital Elements 83 Appendix C: Useful Derivatives for the Geopotential Calculations 87 Appendix D...replaced by two equinoctial elements , h and k (from a coordinate system with singularities at i = x and for rectilinear orbits ). Also, for long term 3...0. 10 and 0.55 i 15.5) a more well behaved set of variables will be used: two of the equinoctial elements , h and k. These elements eliminate the
Recent trends in the development of heat exchangers for geothermal systems
NASA Astrophysics Data System (ADS)
Franco, A.; Vaccaro, M.
2017-11-01
The potential use of geothermal resources has been a remarkable driver for market players and companies operating in the field of geothermal energy conversion. For this reason, medium to low temperature geothermal resources have been the object of recent rise in consideration, with strong reference to the perspectives of development of Organic Rankine Cycle (ORC) technology. The main components of geothermal plants based on ORC cycle are surely the heat exchangers. A lot of different heat exchangers are required for the operation of ORC plants. Among those it is surely of major importance the Recovery Heat Exchanger (RHE, typically an evaporator), in which the operating fluid is evaporated. Also the Recuperator, in regenerative Organic Rankine Cycle, is of major interest in technology. Another important application of the heat exchangers is connected to the condensation, according to the possibility of liquid or air cooling media availability. The paper analyzes the importance of heat exchangers sizing and the connection with the operation of ORC power plants putting in evidence the real element of innovation: the consideration of the heat exchangers as central element for the optimum design of ORC systems.
Cossu, Rosa Maria; Casola, Claudio; Giacomello, Stefania; Vidalis, Amaryllis
2017-01-01
Abstract The accumulation and removal of transposable elements (TEs) is a major driver of genome size evolution in eukaryotes. In plants, long terminal repeat (LTR) retrotransposons (LTR-RTs) represent the majority of TEs and form most of the nuclear DNA in large genomes. Unequal recombination (UR) between LTRs leads to removal of intervening sequence and formation of solo-LTRs. UR is a major mechanism of LTR-RT removal in many angiosperms, but our understanding of LTR-RT-associated recombination within the large, LTR-RT-rich genomes of conifers is quite limited. We employ a novel read-based methodology to estimate the relative rates of LTR-RT-associated UR within the genomes of four conifer and seven angiosperm species. We found the lowest rates of UR in the largest genomes studied, conifers and the angiosperm maize. Recombination may also resolve as gene conversion, which does not remove sequence, so we analyzed LTR-RT-associated gene conversion events (GCEs) in Norway spruce and six angiosperms. Opposite the trend for UR, we found the highest rates of GCEs in Norway spruce and maize. Unlike previous work in angiosperms, we found no evidence that rates of UR correlate with retroelement structural features in the conifers, suggesting that another process is suppressing UR in these species. Recent results from diverse eukaryotes indicate that heterochromatin affects the resolution of recombination, by favoring gene conversion over crossing-over, similar to our observation of opposed rates of UR and GCEs. Control of LTR-RT proliferation via formation of heterochromatin would be a likely step toward large genomes in eukaryotes carrying high LTR-RT content. PMID:29228262
Thermoelectric energy converter for generation of electricity from low-grade heat
Jayadev, T.S.; Benson, D.K.
1980-05-27
A thermoelectric energy conversion device which includes a plurality of thermoelectric elements is described. A hot liquid is supplied to one side of each element and a cold liquid is supplied to the other side of each element. The thermoelectric generator may be utilized to produce power from low-grade heat sources such as ocean thermal gradients, solar ponds, and low-grade geothermal resources. (WHK)
Analysis of the attainable efficiency of a direct-bandgap betavoltaic element
NASA Astrophysics Data System (ADS)
Sachenko, A. V.; Shkrebtii, A. I.; Korkishko, R. M.; Kostylyov, V. P.; Kulish, M. R.; Sokolovskyi, I. O.; Evstigneev, M.
2015-11-01
Conversion of energy of beta-particles into electric energy in a p-n junction based on direct-bandgap semiconductors, such as GaAs, is analyzed considering realistic semiconductor system parameters. An expression for the collection coefficient, Q, of the electron-hole pairs generated by beta-electrons is derived taking into account the existence of the dead layer. We show that the collection coefficient of beta-electrons emitted by a 3H-source to a GaAs p-n junction is close to 1 in a broad range of electron lifetimes in the junction, ranging from 10-9to 10-7 s. For the combination 147Pm/GaAs, Q is relatively large (≥slant 0.4) only for quite long lifetimes (about 10-7 s) and large thicknesses (about 100 μm) of GaAs p-n junctions. For realistic lifetimes of minority carriers and their diffusion coefficients, the open-circuit voltage realized due to the irradiation of a GaAs p-n junction by beta-particles is obtained. The attainable beta-conversion efficiency η in the case of a 3H/GaAs combination is found to exceed that of the 147Pm/GaAs combination.
Assessment of potentially harmful elements pollution in the Calore River basin (Southern Italy).
Zuzolo, Daniela; Cicchella, Domenico; Catani, Vittorio; Giaccio, Lucia; Guagliardi, Ilaria; Esposito, Libera; De Vivo, Benedetto
2017-06-01
The geographical distribution of concentration values for harmful elements was determined in the Campania region, Italy. The study area consists of the drainage basin of the River Calore, a tributary of the river Volturno, the largest Southern Italian river. The results provide reliable analytical data allowing a quantitative assessment of the trace element pollution threat to the ecosystem and human health. Altogether 562 stream sediment samples were collected at a sampling density of 1 site per 5 km 2 . All samples were air-dried, sieved to <100 mesh fraction and analyzed for 37 elements after an aqua regia extraction by a combination of ICP-AES and ICP-MS. In addition to elemental analysis, gamma-ray spectrometry data were collected (a total of 562 measurements) using a hand-held Scintrex GRS-500 spectrometer. Statistical analyses were performed to show the single-element distribution and the distribution of elemental association factor scores resulting from R-mode factor analyses. Maps showing element distributions were made using GeoDAS and ArcGIS software. Our study showed that, despite evidence from concentrations of many elements for enrichment over natural background values, the spatial distribution of major and trace elements in Calore River basin is determined mostly by geogenic factors. The southwestern area of the basin highlighted an enrichment of many elements potentially harmful for human health and other living organisms (Al, Fe, K, Na, As, Cd, La, Pb, Th, Tl, U); however, these anomalies are due to the presence of pyroclastic and alkaline volcanic lithologies. Even where sedimentary lithologies occur, many harmful elements (Co, Cr, Mn, Ni) showed high concentration levels due to natural origins. Conversely, a strong heavy metal contamination (Pb, Zn, Cu, Sb, Ag, Au, Hg), due to an anthropogenic contribution, is highlighted in many areas characterized by the presence of road junctions, urban settlements and industrial areas. The enrichment factor of these elements is 3-4 times higher than the background values. The southwestern area of the basin is characterized by a moderate/high degree of contamination, just where the two busiest roads of the area run and the highest concentration of industries occurs.
"It's Insanely Useful!" Students' Use of Instructional Concepts in Group Work and Individual Writing
ERIC Educational Resources Information Center
Rodnes, Kari Anne
2012-01-01
This study investigates students' work on analyzing a literary text, a cartoon strip, with focus on their use of instructional, analytical concepts. Excerpts from a group conversation and from individually written texts are analyzed from a sociocultural, dialogical perspective. The analysis of the conversation shows how such concepts help the…
A Content Analysis of Themes That Emerge from School Principals' Web2.0 Conversations
ERIC Educational Resources Information Center
Manning, Rory
2011-01-01
The purpose of this qualitative study was to analyze the self initiated conversations held by school principals on web2.o platforms, such as blogs, through the lens of current leadership standards. The online writings of thirteen school principals were analyzed using grounded theory techniques (Strauss and Corbin, 1998) to elucidate emerging…
Analysis of Shublik Formation rocks from Mt. Michelson quadrangle, Alaska
Detterman, Robert L.
1970-01-01
Analysis of 88 samples from the Shublik formation on Fire Creek, Mt. Michelson Quadrangle, Alaska, are presented in tabular form. The results include the determination of elements by semiquantitative spectrographic analysis, phosphate by X-ray fluorescence, carbon dioxide by acid decomposable carbonate, total carbon by induction furnace, carbonate carbon by conversion using the conversion factor of 0.2727 for amount of carbon in carbon dioxide, and organic carbon by difference. A seven- cycle semilogarithmic chart presents the data graphically and illustrates the range, mode, and mean for some of the elements. The chart shows, also, the approximate concentration of the same elements in rocks similar to the black shale and limestone of the Shublik Formation. Each sample represents 5 feet of section and is composed of rock chips taken at 1 - foot intervals. The samples are keyed into a stratigraphic column of the formation. Rocks of the Shublik Formation contain anomalously high concentrations of some of the elements. These same elements might be expected to be high in some of the petroleum from northern Alaska if the Shublik Formation is a source for this petroleum. Several of the stratigraphic intervals may represent, also, a low-grade phosphate deposit.
Agricultural Land Conversion: Background and Issues.
ERIC Educational Resources Information Center
Furuseth, Owen J.
1982-01-01
Analyzes forces contributing to the conversion of agricultural land for other uses, causes for the depletion of the land, major issues surrounding the loss of farmland, and current policies designed to control haphazard land conversion. Concludes that the United States lacks a national farmland protection policy. (KC)
Conversational high resolution mass spectrographic data reduction
NASA Technical Reports Server (NTRS)
Romiez, M. P.
1973-01-01
A FORTRAN 4 program is described which reduces the data obtained from a high resolution mass spectrograph. The program (1) calculates an accurate mass for each line on the photoplate, and (2) assigns elemental compositions to each accurate mass. The program is intended for use in a time-shared computing environment and makes use of the conversational aspects of time-sharing operating systems.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Fomin, V.M.; Lunin, A.V.; Aleksandrov, Yu.A.
1988-03-10
Occurrence of the reaction under study was followed from the decrease in hydroperoxide or of Mo(CO)/sub 6/. The Mo(CO)/sub 6/ content of the reaction was found by determining either the concentration of this compound directly or by determining the concentration of the gaseous products from its transformations (CO + CO/sub 2/). Hydroperoxides (I) and (II) were determined iodometrically. Metal-containing products of the oxidation of Mo(CO)/sub 6/, molybdenum oxides and peroxides, were analyzed by IR and ESR spectroscopy, elemental analysis, and iodometry. Analysis of transformation products of the hydroperoxides (phenol, acetone, dimethylphenylcarbinol, acetophenone, tert-butyl alcohol, water, and oxygen) was performed usingmore » gas chromatography. Results are presented.« less
The legacy of Tom Andersen: The ethics of reflecting processes.
Gehart, Diane R
2018-03-08
Tom Andersen and his pioneering work with reflecting conservations has had a lasting influence on the field of family therapy and mental health more broadly. Most family therapists are familiar with his contributions related to reflecting teams; however, fewer are familiar with his conceptualization of reflecting processes, which offer practical ways to approach therapeutic conversations to address challenging problems. This article provides a brief history of Andersen's career and reviews four key elements of his approach, including: (a) his way of being in relationship, (b) appropriately unusual comments, (c) inner and outer dialogs, and (d) ethics of dialogical relating. Finally, this article introduces readers to the context of the video that will be analyzed in the articles that follow in this special section. © 2018 American Association for Marriage and Family Therapy.
OSMEAN - OSCULATING/MEAN CLASSICAL ORBIT ELEMENTS CONVERSION (HP9000/7XX VERSION)
NASA Technical Reports Server (NTRS)
Guinn, J. R.
1994-01-01
OSMEAN is a sophisticated FORTRAN algorithm that converts between osculating and mean classical orbit elements. Mean orbit elements are advantageous for trajectory design and maneuver planning since they can be propagated very quickly; however, mean elements cannot describe the exact orbit at any given time. Osculating elements will enable the engineer to give an exact description of an orbit; however, computation costs are significantly higher due to the numerical integration procedure required for propagation. By calculating accurate conversions between osculating and mean orbit elements, OSMEAN allows the engineer to exploit the advantages of each approach for the design and planning of orbital trajectories and maneuver planning. OSMEAN is capable of converting mean elements to osculating elements or vice versa. The conversion is based on modelling of all first order aspherical and lunar-solar gravitation perturbations as well as a second-order aspherical term based on the second degree central body zonal perturbation. OSMEAN is written in FORTRAN 77 for HP 9000 series computers running HP-UX (NPO-18796) and DEC VAX series computers running VMS (NPO-18741). The HP version requires 388K of RAM for execution and the DEC VAX version requires 254K of RAM for execution. Sample input and output are listed in the documentation. Sample input is also provided on the distribution medium. The standard distribution medium for the HP 9000 series version is a .25 inch streaming magnetic IOTAMAT tape cartridge in UNIX tar format. It is also available on a .25 inch streaming magnetic tape cartridge in UNIX tar format or on a 3.5 inch diskette in UNIX tar format. The standard distribution medium for the DEC VAX version is a 1600 BPI 9-track magnetic tape in DEC VAX BACKUP format. It is also available on a TK50 tape cartridge in DEC VAX BACKUP format. OSMEAN was developed on a VAX 6410 in 1989, and was ported to the HP 9000 series platform in 1991. It is a copyrighted work with all copyright vested in NASA.
OSMEAN - OSCULATING/MEAN CLASSICAL ORBIT ELEMENTS CONVERSION (VAX VMS VERSION)
NASA Technical Reports Server (NTRS)
Guinn, J. R.
1994-01-01
OSMEAN is a sophisticated FORTRAN algorithm that converts between osculating and mean classical orbit elements. Mean orbit elements are advantageous for trajectory design and maneuver planning since they can be propagated very quickly; however, mean elements cannot describe the exact orbit at any given time. Osculating elements will enable the engineer to give an exact description of an orbit; however, computation costs are significantly higher due to the numerical integration procedure required for propagation. By calculating accurate conversions between osculating and mean orbit elements, OSMEAN allows the engineer to exploit the advantages of each approach for the design and planning of orbital trajectories and maneuver planning. OSMEAN is capable of converting mean elements to osculating elements or vice versa. The conversion is based on modelling of all first order aspherical and lunar-solar gravitation perturbations as well as a second-order aspherical term based on the second degree central body zonal perturbation. OSMEAN is written in FORTRAN 77 for HP 9000 series computers running HP-UX (NPO-18796) and DEC VAX series computers running VMS (NPO-18741). The HP version requires 388K of RAM for execution and the DEC VAX version requires 254K of RAM for execution. Sample input and output are listed in the documentation. Sample input is also provided on the distribution medium. The standard distribution medium for the HP 9000 series version is a .25 inch streaming magnetic IOTAMAT tape cartridge in UNIX tar format. It is also available on a .25 inch streaming magnetic tape cartridge in UNIX tar format or on a 3.5 inch diskette in UNIX tar format. The standard distribution medium for the DEC VAX version is a 1600 BPI 9-track magnetic tape in DEC VAX BACKUP format. It is also available on a TK50 tape cartridge in DEC VAX BACKUP format. OSMEAN was developed on a VAX 6410 in 1989, and was ported to the HP 9000 series platform in 1991. It is a copyrighted work with all copyright vested in NASA.
Study on Conversion Between Momentum and Contrarian Based on Fractal Game
NASA Astrophysics Data System (ADS)
Wu, Xu; Song, Guanghui; Deng, Yan; Xu, Lin
2015-06-01
Based on the fractal game which is performed by the majority and the minority, the fractal market theory (FMT) is employed to describe the features of investors' decision-making. Accordingly, the process of fractal games is formed in order to analyze the statistical features of conversion between momentum and contrarian. The result shows that among three fractal game mechanisms, the statistical feature of simulated return rate series is much more similar to log returns on actual series. In addition, the conversion between momentum and contrarian is also extremely similar to real situation, which can reflect the effectiveness of using fractal game in analyzing the conversion between momentum and contrarian. Moreover, it also provides decision-making reference which helps investors develop effective investment strategy.
Informed Decision Making for Percutaneous Coronary Intervention for Stable Coronary Disease.
Rothberg, Michael B; Sivalingam, Senthil K; Kleppel, Reva; Schweiger, Marc; Hu, Bo; Sepucha, Karen R
2015-07-01
Patients with stable coronary disease undergoing percutaneous coronary intervention (PCI) are frequently misinformed about the benefits of PCI. Little is known about the quality of decision making before angiography and possible PCI. To assess the quality of informed decision making and its association with patient decisions. We performed a cross-sectional analysis of recorded conversations between August 1, 2008, and August 31, 2012, among adults with known or suspected stable coronary disease at outpatient cardiology practices. Presence of 7 elements of informed decision making and the decision to undergo angiography and possible PCI. Of 59 conversations conducted by 23 cardiologists, 2 (3%) included all 7 elements of informed decision making; 8 (14%) met a more limited definition of procedure, alternatives, and risks. Specific elements significantly associated with not choosing angiography and possible PCI included discussion of uncertainty (odds ratio [OR], 20.5; 95% CI, 2.3-204.9), patient's role (OR, 5.3; 95% CI, 1.3-21.3), exploration of alternatives (OR, 9.5; 95% CI, 2.5-36.5), and exploration of patient preference (OR, 4.8; 95% CI, 1.2-19.4). Neither the presence of angina nor severity of symptoms was associated with choosing angiography and possible PCI. In a multivariable analysis using the total number of elements as a predictor, better informed patients were less likely to choose angiography and possible PCI (OR per additional element, 3.2; 95% CI, 1.4-7.1; P = .005). In conversations between cardiologists and patients with stable angina, informed decision making is often incomplete. More complete discussions are associated with patients choosing not to undergo angiography and possible PCI.
Conversion at large intergenic regions of mitochondrial DNA in Saccharomyces cerevisiae.
Skelly, P J; Clark-Walker, G D
1990-04-01
Saccharomyces cerevisiae mitochondrial DNA deletion mutants have been used to examine whether base-biased intergenic regions of the genome influence mitochondrial biogenesis. One strain (delta 5.0) lacks a 5-kilobase (kb) segment extending from the proline tRNA gene to the small rRNA gene that includes ori1, while a second strain (delta 3.7) is missing a 3.7-kb region between the genes for ATPase subunit 6 and glutamic acid tRNA that encompasses ori7 plus ori2. Growth of these strains on both fermentable and nonfermentable substrates does not differ from growth of the wild-type strain, indicating that the deletable regions of the genome do not play a direct role in the expression of mitochondrial genes. Examination of whether the 5- or 3.7-kb regions influence mitochondrial DNA transmission was undertaken by crossing strains and examining mitochondrial genotypes in zygotic colonies. In a cross between strain delta 5.0, harboring three active ori elements (ori2, ori3, and ori5), and strain delta 3.7, containing only two active ori elements (ori3 and ori5), there is a preferential recovery of the genome containing two active ori elements (37% of progeny) over that containing three active elements (20%). This unexpected result, suggesting that active ori elements do not influence transmission of respiratory-competent genomes, is interpreted to reflect a preferential conversion of the delta 5.0 genome to the wild type (41% of progeny). Supporting evidence for conversion over biased transmission is shown by preferential recovery of a nonparental genome in the progeny of a heterozygous cross in which both parental molecules can be identified by size polymorphisms.
Conversion at large intergenic regions of mitochondrial DNA in Saccharomyces cerevisiae.
Skelly, P J; Clark-Walker, G D
1990-01-01
Saccharomyces cerevisiae mitochondrial DNA deletion mutants have been used to examine whether base-biased intergenic regions of the genome influence mitochondrial biogenesis. One strain (delta 5.0) lacks a 5-kilobase (kb) segment extending from the proline tRNA gene to the small rRNA gene that includes ori1, while a second strain (delta 3.7) is missing a 3.7-kb region between the genes for ATPase subunit 6 and glutamic acid tRNA that encompasses ori7 plus ori2. Growth of these strains on both fermentable and nonfermentable substrates does not differ from growth of the wild-type strain, indicating that the deletable regions of the genome do not play a direct role in the expression of mitochondrial genes. Examination of whether the 5- or 3.7-kb regions influence mitochondrial DNA transmission was undertaken by crossing strains and examining mitochondrial genotypes in zygotic colonies. In a cross between strain delta 5.0, harboring three active ori elements (ori2, ori3, and ori5), and strain delta 3.7, containing only two active ori elements (ori3 and ori5), there is a preferential recovery of the genome containing two active ori elements (37% of progeny) over that containing three active elements (20%). This unexpected result, suggesting that active ori elements do not influence transmission of respiratory-competent genomes, is interpreted to reflect a preferential conversion of the delta 5.0 genome to the wild type (41% of progeny). Supporting evidence for conversion over biased transmission is shown by preferential recovery of a nonparental genome in the progeny of a heterozygous cross in which both parental molecules can be identified by size polymorphisms. Images PMID:2181277
Halas, Stanislaw; Skrzypek, Grzegorz; Meier-Augenstein, Wolfram; Pelc, Andrzej; Kemp, Helen F
2011-03-15
Stable oxygen isotope compositions (δ(18)O values) of two commercial and one synthesized silver orthophosphate reagents have been determined on the VSMOW scale. The analyses were carried out in three different laboratories: lab (1) applying off-line oxygen extraction in the form of CO(2) which was analyzed on a dual inlet and triple collector isotope ratio mass spectrometer, while labs (2) and (3) employed an isotope ratio mass spectrometer coupled to a high-temperature conversion/elemental analyzer (TC/EA) where Ag(3)PO(4) samples were analyzed as CO in continuous flow mode. The δ(18)O values for the proposed new comparison materials were linked to the generally accepted δ(18)O values for Vennemann's TU-1 and TU-2 standards as well as for Ag(3)PO(4) extracted from NBS120c. The weighted average δ(18)O(VSMOW) values for the new comparison materials UMCS-1, UMCS-2 and AGPO-SCRI were determined to be + 32.60 (± 0.12), + 19.40 (± 0.12) and + 14.58 (± 0.13)‰, respectively. Copyright © 2011 John Wiley & Sons, Ltd.
Simulation Analysis of Tilted Polyhedron-Shaped Thermoelectric Elements
NASA Astrophysics Data System (ADS)
Meng, Xiangning; Suzuki, Ryosuke O.
2015-06-01
The generation of thermoelectricity is considered a promising approach to harness the waste heat generated in industries, automobiles, gas fields, and other man-made processes. The waste heat can be converted to electricity via a thermoelectric (TE) generator. In this light, the generator performance depends on the geometric configuration of its constituent elements as well as their material properties. Our previous work reported TE behaviors for modules consisting of parallelogram-shaped elements, because elements with tilted laminate structures provide increased mechanical stability and efficient heat-transferring ability from the hot surface to the cold surface. Here, we study TE elements in the shape of a polyhedron that is obtained by mechanically truncating the edges of a parallelogram element in order to further enhance the generator performance and reduce TE material usage. The TE performance of the modules consisting of these polyhedron elements is numerically simulated by using the finite-volume method. The output power, voltage, and current of the polyhedral TE module are greater than those of the parallelogram-element module. The polyhedron shape positively affects heat transfer and the flow of electric charges in the light of increasing the efficiency of conversion from heat to electricity. By varying the shape of the truncated portions, we determine the optimal shape that enables homogeneous heat flux distribution and slow diffusion of thermal energy to obtain the better efficiency of conversion of heat into electricity. We believe that the findings of our study can significantly contribute to the design policy in TE generation.
Mapping the online communication patterns of political conversations
NASA Astrophysics Data System (ADS)
Borondo, J.; Morales, A. J.; Benito, R. M.; Losada, J. C.
2014-11-01
The structure of the social networks in which individuals are embedded influences their political choices and therefore their voting behavior. Nowadays, social media represent a new channel for individuals to communicate, what together with the availability of the data, makes it possible to analyze the online social network resulting from political conversations. Here, by taking advantage of the recently developed techniques to analyze complex systems, we map the communication patterns resulting from Spanish political conversations. We identify the different existing communities, building networks of communities, and finding that users cluster themselves in politically homogeneous networks. We found that while most of the collective attention was monopolized by politicians, traditional media accounts were still the preferred sources from which to propagate information. Finally, we propose methods to analyze the use of different languages, finding a clear trend from sympathizers of several political parties to overuse or infra-use each language. We conclude that, on the light of a social media analysis perspective, the political conversation is constrained by both ideology and language.
K-shell photoelectric cross sections for intermediate-Z elements at 26 keV
NASA Astrophysics Data System (ADS)
Kumar, Suresh; Singh, N.; Allawadhi, K. L.; Sood, B. S.
1986-08-01
Our earlier measurements of K-shell photoelectric cross sections for intermediate Z elements at 74 and 37 keV have been extended to 26 keV using external conversion x rays in Sn. The experimental results are found to show fairly good agreement with the theoretical values of Scofield.
Finite element simulation of core inspection in helicopter rotor blades using guided waves.
Chakrapani, Sunil Kishore; Barnard, Daniel; Dayal, Vinay
2015-09-01
This paper extends the work presented earlier on inspection of helicopter rotor blades using guided Lamb modes by focusing on inspecting the spar-core bond. In particular, this research focuses on structures which employ high stiffness, high density core materials. Wave propagation in such structures deviate from the generic Lamb wave propagation in sandwich panels. To understand the various mode conversions, finite element models of a generalized helicopter rotor blade were created and subjected to transient analysis using a commercial finite element code; ANSYS. Numerical simulations showed that a Lamb wave excited in the spar section of the blade gets converted into Rayleigh wave which travels across the spar-core section and mode converts back into Lamb wave. Dispersion of Rayleigh waves in multi-layered half-space was also explored. Damage was modeled in the form of a notch in the core section to simulate a cracked core, and delamination was modeled between the spar and core material to simulate spar-core disbond. Mode conversions under these damaged conditions were examined numerically. The numerical models help in assessing the difficulty of using nondestructive evaluation for complex structures and also highlight the physics behind the mode conversions which occur at various discontinuities. Copyright © 2015 Elsevier B.V. All rights reserved.
Hybrid piezoelectric energy harvesting transducer system
NASA Technical Reports Server (NTRS)
Xu, Tian-Bing (Inventor); Jiang, Xiaoning (Inventor); Su, Ji (Inventor); Rehrig, Paul W. (Inventor); Hackenberger, Wesley S. (Inventor)
2008-01-01
A hybrid piezoelectric energy harvesting transducer system includes: (a) first and second symmetric, pre-curved piezoelectric elements mounted separately on a frame so that their concave major surfaces are positioned opposite to each other; and (b) a linear piezoelectric element mounted separately on the frame and positioned between the pre-curved piezoelectric elements. The pre-curved piezoelectric elements and the linear piezoelectric element are spaced from one another and communicate with energy harvesting circuitry having contact points on the frame. The hybrid piezoelectric energy harvesting transducer system has a higher electromechanical energy conversion efficiency than any known piezoelectric transducer.
Doing Conversation Analysis: A Practical Guide.
ERIC Educational Resources Information Center
ten Have, Paul
Noting that conversation analysis (CA) has developed into one of the major methods of analyzing speech in the disciplines of communications, linguistics, anthropology and sociology, this book demonstrates in a practical way how to become a conversation analyst. As well as providing an overall introduction to the approach, it focuses on the…
Socialization As and through Conversation: Political Discourse in Israeli Families.
ERIC Educational Resources Information Center
Ribak, Rivka
1997-01-01
Survey of Israeli parent-child pairs revealed portraits of moderate parents and radical children, but follow-up of family conversation while watching and discussing television news suggested harmony and unity in Israeli living rooms. Reconceptualization of the theoretical canon of political socialization analyzes the conversation as a moment of…
Conversational Coherency. Technical Report No. 95.
ERIC Educational Resources Information Center
Reichman, Rachel
To analyze the process involved in maintaining conversational coherency, the study described in this paper used a construct called a "context space" that grouped utterances referring to a single issue or episode. The paper defines the types of context spaces, parses individual conversations to identify the underlying model or structure,…
Transforming Mean and Osculating Elements Using Numerical Methods
NASA Technical Reports Server (NTRS)
Ely, Todd A.
2010-01-01
Mean element propagation of perturbed two body orbits has as its mathematical basis averaging theory of nonlinear dynamical systems. Averaged mean elements define the long-term evolution characteristics of an orbit. Using averaging theory, a near identity transformation can be found that transforms the mean elements back to the osculating elements that contain short period terms in addition to the secular and long period mean elements. The ability to perform the conversion is necessary so that orbit design conducted in mean elements can be converted back into osculating results. In the present work, this near identity transformation is found using the Fast Fourier Transform. An efficient method is found that is capable of recovering the osculating elements to first order
Yin, Xijie; Chen, Zhigang
2014-12-01
The thermal conversion/elemental analyzer-isotope ratio mass spectrometer (TC/EA-IRMS) is widely used to measure the δ(18) O value of various substances. A premise for accurate δ(18) O measurement is that the oxygen in the sample can be converted into carbon monoxide (CO) quantitatively or at least proportionally. Therefore, a precise method to determine the oxygen yield of TC/EA-IRMS measurements is needed. Most studies have used the CO peak area obtained from a known amount of a solid reference material (for example, benzoic acid) to calibrate the oxygen yield of the sample. Although it was assumed that the oxygen yield of the solid reference material is 100%, no direct evidence has been provided. As CO is the analyte gas for δ(18) O measurement by IRMS, in this study, we use a six-port valve to inject CO gas into the TC/EA. The CO is carried to the IRMS by the He carrier gas and the CO peak area is measured by the IRMS. The CO peak area thus obtained from a known amount of the injected CO is used to calibrate the oxygen yield of the sample. The oxygen yields of commonly used organic and inorganic reference materials such as benzoic acid (C6 H5 COOH), silver phosphate (Ag3 PO4 ), calcium carbonate (CaCO3 ) and silicon dioxide (SiO2 ) are investigated at different reactor temperatures and sample sizes. We obtained excellent linear correlation between the peak area for the injected CO and its oxygen atom amount. C6 H5 COOH has the highest oxygen yield, followed by Ag3 PO4 , CaCO3 and SiO2 . The oxygen yields of TC/EA-IRMS are less than 100% for both organic and inorganic substances, but the yields are relatively stable at the specified reactor temperature and for a given quantity of sample. Copyright © 2014 John Wiley & Sons, Ltd.
Condenser design for AMTEC power conversion
NASA Technical Reports Server (NTRS)
Crowley, Christopher J.
1991-01-01
The condenser and the electrodes are the two elements of an alkali metal thermal-to-electric conversion (AMTEC) cell which most greatly affect the energy conversion performance. A condenser is described which accomplishes two critical functions in an AMTEC cell: management of the fluid under microgravity conditions and optimization of conversion efficiency. The first function is achieved via the use of a controlled surface shape, along with drainage grooves and arteries to collect the fluid. Capillary forces manage the fluid in microgravity and dominate hydrostatic effects on the ground so the device is ground-testable. The second function is achieved via a smooth film of highly reflective liquid sodium on the condensing surface, resulting in minimization of parasitic heat losses due to radiation heat transfer. Power conversion efficiencies of 25 percent to 30 percent are estimated with this condenser using present technology for the electrodes.
NASA Astrophysics Data System (ADS)
Knyaz'kov, A.; Pustovykh, O.; Verevkin, A.; Terekhin, V.; Shachek, A.; Tyasto, A.
2016-04-01
It is shown that in order to form the current pulse of a near rectangular shape, which provides conversion of the welding arc into a dynamic mode, it is rational to connect a forming element made on the basis of an artificial forming line in series to the welding DC circuit. The paper presents a diagram of a pulsed device for welding with a non-consumable electrode in argon which was developed using the forming element. The conversion of the arc into the dynamic mode is illustrated by the current and voltage oscillograms of the arc gap and the dynamic characteristic of the arc within the interval of one pulse generation time in the arc gap. The background current travels in the interpulse interval.
NASA Astrophysics Data System (ADS)
Barnard, Daniel; Chakrapani, Sunil Kishore; Dayal, Vinay
2013-01-01
Modern helicopter rotor blades constructed of composite materials offer significant inspection challenges, particularly at inner structures, where geometry and differing material properties and anisotropy make placement of the probing energy difficult. This paper presents an application of Lamb waves to these structures, where mode conversion occurs at internal geometric discontinuities. These additional modes were found to successfully propagate to the targeted regions inside the rotor and back out, allowing evaluation of the structure. A finite element model was developed to simulate wave propagation and mode conversion in the structure and aid in identifying the signals received in the laboratory experiment. A good correlation between numerical and experimental results was observed.
NASA Technical Reports Server (NTRS)
Peterson, B.
1978-01-01
The present situation and possible developments over the period 1970-1985 for active semiconductor elements in the microwave range are outlined. After a short historical survey of FT techniques, the following are discussed: Generation, power amplification, amplification of small signals, frequency conversion, detection, electronic signal control and integrated microwave circuits.
Memory-Metal Electromechanical Actuators
NASA Technical Reports Server (NTRS)
Ruoff, C. F.
1984-01-01
Electrically controlled actuator produces predetermined force, torque, or displacement without motors, solenoids, or gears. Using memory-metal elements, actuator responds to digital input without electronic digitalto-analog conversion. To prevent overheating and consequent loss of hotformed shape, each element protected by thermostat turns off current when predetermined temperature is exceeded. Memory metals used to generate fast mechanical response to electric signals.
Analyzing Rumors, Gossip, and Urban Legends through Their Conversational Properties
ERIC Educational Resources Information Center
Guerin, Bernard; Miyazaki, Yoshihiko
2006-01-01
A conversational approach is developed to explain the ubiquitous presence of rumors, urban legends, and gossip as arising from their conversational properties rather than from side effects of cognitive processing or "effort after meaning." It is suggested that the primary function of telling rumors, gossip, and urban legends is not to impart…
An Analysis of How Carl Rogers Enacted Client-Centered Conversation with Gloria.
ERIC Educational Resources Information Center
Wickman, Scott A.; Campbell, Cynthia
2003-01-01
This study analyzed Carl Rogers's session with Gloria in "Three Approaches to Psychotherapy" to determine how Rogers's conversational style functioned to enact his core conditions of empathy, genuineness, and unconditional positive regard. Rogers's conversational style was found to be congruent with his espoused theory as well as a…
NASA Technical Reports Server (NTRS)
Gutmann, R. J.; Borrego, J. M.
1978-01-01
Rectenna conversion efficiencies (RF to dc) approximating 85 percent were demonstrated on a small scale, clearly indicating the feasibility and potential of efficiency of microwave power to dc. The overall cost estimates of the solar power satellite indicate that the baseline rectenna subsystem will be between 25 to 40 percent of the system cost. The directional receiving elements and element extensions were studied, along with power combining evaluation and evaluation extensions.
Informed Consent Conversations and Documents: A Quantitative Comparison
Koyfman, Shlomo A.; Reddy, Chandana A.; Hizlan, Sabahat; Leek, Angela C.; Kodish, Eric
2015-01-01
Background Informed consent for clinical research includes two components: informed consent documents (ICD) and informed consent conversations (ICC). Readability software has been used to help simplify the language of the ICD, but rarely employed to assess the language during the ICC, which may influence the quality of informed consent. This analysis was completed to determine if length and reading levels of transcribed ICCs are lower than their corresponding ICDs for selected clinical trials, and to assess whether investigator experience affected use of simpler language and comprehensiveness. Methods Prospective study where ICCs were audio-recorded at 6 institutions when families were offered participation in pediatric phase I oncology trials. Word count, Flesch-Kincaid Grade Level (FKGL) and Flesch Reading Ease Score (FRES) of ICCs were compared to corresponding ICDs, including the frequency that investigators addressed 8 pre-specified critical consent elements during the ICC. Results Sixty-nine unique physician/protocol pairs were identified. Overall, ICCs contained fewer words (4,677 vs. 6,364; p=0.0016), had lower FKGL (6 vs. 9.7; p=<0.0001) and higher FRES (77.8 vs. 56.7; p<0.0001) than their respective ICDs, but were more likely to omit critical consent elements, such as voluntariness (55%) and dose limiting toxicities (26%). Years of investigator experience was not correlated with reliably covering critical elements or decreased linguistic complexity. Conclusions Clinicians use more understandable language during ICCs than the corresponding ICD, but less reliably cover elements critical to fully informed consent. Focused efforts at providing communication training for clinician-investigators should be done to optimize the synergy between the ICD and conversation. PMID:26505269
Friction modifier using adherent metallic multilayered or mixed element layer conversion coatings
NASA Technical Reports Server (NTRS)
Schramm, Harry F. (Inventor); Defalco, Frank G. (Inventor); Starks, Sr., Lloyd L. (Inventor)
2012-01-01
A process for creating conversion coatings and spin, drawing, and extrusion finishes for surfaces, wherein the conversion coatings and spin, drawing, and extrusion finishes contain potassium, phosphorus, nitrogen, silicon, and one or more non-alkaline metals. The process comprises forming a first aqueous solution of silicate, potassium hydroxide, and ammonium hydroxide; forming a second aqueous solution of water, phosphoric acid, ammonium hydroxide, an alkali metal hydroxide, and one or more non-alkaline metals, and then combining the first solution with the second solution to form a final solution. This final solution forms an anti-friction multi-layer conversion coating or a spin, drawing, and extrusion finish on a surface when applied to the surface, either directly or as an additive in lubricating fluids.
1990-08-01
Computer Conferencing ’ DTIC •ELECTEM. b ~Novo JIML 0*- B August 1990 Field Element al Boise, Idaho Field Unit at Fort Knox, Kentucky Training Resecarch...Distributed Training for the Reserve Component: Course Conversion and implementation Guidelines for Computer (onferencing _________________ __________ 12...identify by block number) FIELD GROUP SUB-GROT;W Asynchironous computer conferencing ’rt i1inimg technology _____ 1Reserve Component jtr ibuted
NASA Astrophysics Data System (ADS)
St. Prix, Courtney Desmond
This dissertation examines the concerns of fourteen, low-income, urban parents for their children's needs in education in general and science education in particular. A motivation behind this investigation is to resist the top-down dissemination of educational policy and value the perspectives of so-called "culturally deprived" parents. I contrast the parents' vision for science education with those expressed by AAAS and NRC. I collected data through interviews, conversation groups, and participant observation conducted at a homeless shelter in a major American city. Initially, I conducted individual interviews that were coded, and themes of social mobility and issues of pedagogy surfaced as major areas of concern for parents. I developed questions under each theme for discussion with parents in conversation groups comprised of five parents. Additional conversation groups were developed later under emergent themes of parent-school relations and science education reform. As an assistant in both the after-school program and the parent-teachers association, I obtained additional data through field-notes. I analyzed the data using critical theory as my lens. However, it was a critical theory that had been repositioned from a eurocentric viewpoint to encompass the critical elements that emerge through the struggles of people of color and women. The parents considered the educational system to be uncaring and inflexible. They expressed that science is not taught in an engaging manner that is relevant to the lives of poor students. There was a great deal of overlap between the parents' vision and that of the science education reform initiatives. However, while the reform initiatives focused on "what" and "how" science was being taught, the parents' recommendations focused on "who" was being taught. They called for a more flexible, caring educational system that pays attention to the needs of the whole child. Finally, I analyzed the parents' perspectives as reflecting enculturation, resistance, or the "third space." This analytical approach helped emphasize the need for dialogue between parents, administrators, and teachers. It showed the need for them to interact in a zone of struggle, but emerge with a shared and understood vision for the development of all children in education and science education.
NASA Technical Reports Server (NTRS)
2009-01-01
Topics covered include: Direct-Solve Image-Based Wavefront Sensing; Use of UV Sources for Detection and Identification of Explosives; Using Fluorescent Viruses for Detecting Bacteria in Water; Gradiometer Using Middle Loops as Sensing Elements in a Low-Field SQUID MRI System; Volcano Monitor: Autonomous Triggering of In-Situ Sensors; Wireless Fluid-Level Sensors for Harsh Environments; Interference-Detection Module in a Digital Radar Receiver; Modal Vibration Analysis of Large Castings; Structural/Radiation-Shielding Epoxies; Integrated Multilayer Insulation; Apparatus for Screening Multiple Oxygen-Reduction Catalysts; Determining Aliasing in Isolated Signal Conditioning Modules; Composite Bipolar Plate for Unitized Fuel Cell/Electrolyzer Systems; Spectrum Analyzers Incorporating Tunable WGM Resonators; Quantum-Well Thermophotovoltaic Cells; Bounded-Angle Iterative Decoding of LDPC Codes; Conversion from Tree to Graph Representation of Requirements; Parallel Hybrid Vehicle Optimal Storage System; and Anaerobic Digestion in a Flooded Densified Leachbed.
Economic Impact of Laparoscopic Conversion to Open in Left Colon Resections.
Etter, Katherine; Davis, Brad; Roy, Sanjoy; Kalsekar, Iftekhar; Yoo, Andrew
2017-01-01
Studies have shown economic and clinical advantages of laparoscopic left-colon resections. Laparoscopic conversion to open is an important surgical outcome. We estimated conversion incidence, identified risk factors, and measured the clinical and economic impact. In this retrospective study, we used the Premier Perspective database to analyze left-sided colectomies from 2009 to 2014. Operating room time (ORT), length of stay (LOS), total hospital cost (2014 U.S. dollars); along with incidence of in-hospital clinical outcomes (anastomotic leak surrogate [Leak], transfusion, and mortality) were evaluated. Multivariable models accounting for hospital clustering were used to identify conversion risk factors and analyze the effect of conversion on economic and clinical outcomes. A total of 41,417 patients: 8,468 left hemicolectomy and 32,949 sigmoidectomy were identified. Lap-Conversion incidence was 13.3% (95% CI, 12.9-13.7). Adjusted mean LOS (±SE) days was significantly lower for the Lap-Successful group (4.9 compared with Lap-Conversion 6.8 and Open-Planned 7.0), but Lap-Conversion and Open-Planned had similar LOS. Adjusted mean cost was higher for Lap-Conversion $20,165 compared to Open-Planned $18,797; but this difference was smaller than the cost savings for Lap-Successful $16,206 ± $219. Open-Planned had lower odds of Leak compared to Lap-Conversion. Open-Planned and Lap-Conversion had similar odds of transfusion and mortality. Conversion risk factors included inflammatory bowel disease and left-hemicolectomy. Colorectal specialists were associated with 38% decreased odds of conversion. Successful laparoscopic surgery was the most cost effective, with decreased LOS and odds of blood transfusion, leak surrogate, and mortality. Conversion was the most expensive and had increased odds of leak surrogate, but similar LOS compared to Open-Planned. The beneficial effect size of successful laparoscopic surgery was larger than the negative effect of conversion compared to Open-Planned.
Economic Impact of Laparoscopic Conversion to Open in Left Colon Resections
Etter, Katherine; Davis, Brad; Roy, Sanjoy; Kalsekar, Iftekhar
2017-01-01
Background and Objectives: Studies have shown economic and clinical advantages of laparoscopic left-colon resections. Laparoscopic conversion to open is an important surgical outcome. We estimated conversion incidence, identified risk factors, and measured the clinical and economic impact. Methods: In this retrospective study, we used the Premier Perspective database to analyze left-sided colectomies from 2009 to 2014. Operating room time (ORT), length of stay (LOS), total hospital cost (2014 U.S. dollars); along with incidence of in-hospital clinical outcomes (anastomotic leak surrogate [Leak], transfusion, and mortality) were evaluated. Multivariable models accounting for hospital clustering were used to identify conversion risk factors and analyze the effect of conversion on economic and clinical outcomes. Results: A total of 41,417 patients: 8,468 left hemicolectomy and 32,949 sigmoidectomy were identified. Lap-Conversion incidence was 13.3% (95% CI, 12.9–13.7). Adjusted mean LOS (±SE) days was significantly lower for the Lap-Successful group (4.9 compared with Lap-Conversion 6.8 and Open-Planned 7.0), but Lap-Conversion and Open-Planned had similar LOS. Adjusted mean cost was higher for Lap-Conversion $20,165 compared to Open-Planned $18,797; but this difference was smaller than the cost savings for Lap-Successful $16,206 ± $219. Open-Planned had lower odds of Leak compared to Lap-Conversion. Open-Planned and Lap-Conversion had similar odds of transfusion and mortality. Conversion risk factors included inflammatory bowel disease and left-hemicolectomy. Colorectal specialists were associated with 38% decreased odds of conversion. Conclusions: Successful laparoscopic surgery was the most cost effective, with decreased LOS and odds of blood transfusion, leak surrogate, and mortality. Conversion was the most expensive and had increased odds of leak surrogate, but similar LOS compared to Open-Planned. The beneficial effect size of successful laparoscopic surgery was larger than the negative effect of conversion compared to Open-Planned. PMID:28890650
LEM Characterization of Synthetic Jet Actuators Driven by Piezoelectric Element: A Review
Chiatto, Matteo; Capuano, Francesco; Coppola, Gennaro; de Luca, Luigi
2017-01-01
In the last decades, Synthetic jet actuators have gained much interest among the flow control techniques due to their short response time, high jet velocity and absence of traditional piping, which matches the requirements of reduced size and low weight. A synthetic jet is generated by the diaphragm oscillation (generally driven by a piezoelectric element) in a relatively small cavity, producing periodic cavity pressure variations associated with cavity volume changes. The pressured air exhausts through an orifice, converting diaphragm electrodynamic energy into jet kinetic energy. This review paper considers the development of various Lumped-Element Models (LEMs) as practical tools to design and manufacture the actuators. LEMs can quickly predict device performances such as the frequency response in terms of diaphragm displacement, cavity pressure and jet velocity, as well as the efficiency of energy conversion of input Joule power into useful kinetic power of air jet. The actuator performance is also analyzed by varying typical geometric parameters such as cavity height and orifice diameter and length, through a suited dimensionless form of the governing equations. A comprehensive and detailed physical modeling aimed to evaluate the device efficiency is introduced, shedding light on the different stages involved in the process. Overall, the influence of the coupling degree of the two oscillators, the diaphragm and the Helmholtz frequency, on the device performance is discussed throughout the paper. PMID:28587141
NASA Technical Reports Server (NTRS)
Balasubramaniam, R.; Subramanian, R. Shankar
2004-01-01
In this paper we analyze the effects of the following phenomena associated with the thermocapillary migration of a drop. The first is the influence of Newtonian surface rheology of the interface and the second is that of the energy changes associated with stretching and shrinkage of the interfacial area elements, when the drop is in motion. The former occurs because of dissipative processes in the interfacial region, such as when surfactant molecules are adsorbed at the interface in sufficient concentration. The interface is typically modeled in this instance by ascribing to it a surface viscosity. This is a different effect from that of interfacial tension gradients arising from surfactant concentration gradients. The stretching and shrinkage of interfacial area elements leads to changes in the internal energy of these elements that affects the transport of energy in the fluids adjoining the interface. When an element on the interface is stretched, its internal energy increases because of the increase in its area. This energy is supplied by the neighboring fluids that are cooled as a consequence. Conversely, when an element on the interface shrinks, the adjoining fluids are warmed. In the case of a moving drop, elements of interfacial area are stretched in the forward half of the drop, and are shrunk in the rear half. Consequently, the temperature variation on the surface of the drop and its migration speed are modified. The analysis of the motion of a drop including these effects was first performed by LeVan in 1981, in the limit when convective transport of momentum and energy are negligible. We extend the analysis of LeVan to include the convective transport of momentum by demonstrating that an exact solution of the momentum equation is obtained for an arbitrary value of the Reynolds number. This solution is then used to calculate the slightly deformed shape of the drop from a sphere.
ERIC Educational Resources Information Center
Maynard, Senko K.
The casual conversation of six pairs of Japanese and six pairs of American colleges students was analyzed for evidence of two related aspects of conversation management: the linguistic characteristics of utterance units and back-channel strategies. Utterance units are defined as those occurring between identifiable pauses or breaks in tempo.…
Study of the Effectiveness of OCR for Decentralized Data Capture and Conversion. Final Report.
ERIC Educational Resources Information Center
Liston, David M.; And Others
The ERIC network conversion to an OCR (Optical Character Recognition) mode of data entry was studied to analyze the potential effectiveness of OCR data entry for future EPC/s (Editorial Processing Centers). Study results are also applicable to any other system involving decentralized bibliographic data capture and conversion functions. The report…
Effect of Different Types of Small-Group Activities on Students' Conversations
ERIC Educational Resources Information Center
Young, Krista K.; Talanquer, Vicente
2013-01-01
Teaching reform efforts in chemistry education often involve engaging students in small-group activities of different types. This study focused on the analysis of how activity type affected the nature of group conversations. In particular, we analyzed the small-group conversations of students enrolled in a chemistry course for nonscience majors.…
Space Station Freedom power management and distribution design status
NASA Technical Reports Server (NTRS)
Javidi, S.; Gholdston, E.; Stroh, P.
1989-01-01
The design status of the power management and distribution electric power system for the Space Station Freedom is presented. The current design is a star architecture, which has been found to be the best approach for meeting the requirement to deliver 120 V dc to the user interface. The architecture minimizes mass and power losses while improving element-to-element isolation and system flexibility. The design is partitioned into three elements: energy collection, storage and conversion, system protection and distribution, and management and control.
Catalyst for the reduction of sulfur dioxide to elemental sulfur
Jin, Y.; Yu, Q.; Chang, S.G.
1996-02-27
The inventive catalysts allow for the reduction of sulfur dioxide to elemental sulfur in smokestack scrubber environments. The catalysts have a very high sulfur yield of over 90% and space velocity of 10,000 h{sup {minus}1}. They also have the capacity to convert waste gases generated during the initial conversion into elemental sulfur. The catalysts have inexpensive components, and are inexpensive to produce. The net impact of the invention is to make this technology practically available to industrial applications. 21 figs.
Catalyst for the reduction of sulfur dioxide to elemental sulfur
Jin, Yun; Yu, Qiquan; Chang, Shih-Ger
1996-01-01
The inventive catalysts allow for the reduction of sulfur dioxide to elemental sulfur in smokestack scrubber environments. The catalysts have a very high sulfur yield of over 90% and space velocity of 10,000 h.sup.-1. They also have the capacity to convert waste gases generated during the initial conversion into elemental sulfur. The catalysts have inexpensive components, and are inexpensive to produce. The net impact of the invention is to make this technology practically available to industrial applications.
Analysis Center. Areas of Expertise Techno-Economic Analysis Mechanical design 3D modeling/CAD Finite element analysis (FEA) Wave energy conversion Thermal power cycle analysis Research Interests Cost
You Can't Kill a Wasp with a Postage Stamp, or How to Teach 'Em to Pass Element Nine.
ERIC Educational Resources Information Center
Harden, Heather
For student radio broadcasters to acquire a third class operators permit, they must pass Element 9 of the Federal Communications Commission exam. A course was designed to help these amateurs acquire such technical competencies as meter reading, metric conversions, and familiarity with directional antennas. This course description includes a list…
Conversion of evanescent Lamb waves into propagating waves via a narrow aperture edge.
Yan, Xiang; Yuan, Fuh-Gwo
2015-06-01
This paper presents a quantitative study of conversion of evanescent Lamb waves into propagating in isotropic plates. The conversion is substantiated by prescribing time-harmonic Lamb displacements/tractions through a narrow aperture at an edge of a semi-infinite plate. Complex-valued dispersion and group velocity curves are employed to characterize the conversion process. The amplitude coefficient of the propagating Lamb modes converted from evanescent is quantified based on the complex reciprocity theorem via a finite element analysis. The power flow generated into the plate can be separated into radiative and reactive parts made on the basis of propagating and evanescent Lamb waves, where propagating Lamb waves are theoretically proved to radiate pure real power flow, and evanescent Lamb waves carry reactive pure imaginary power flow. The propagating power conversion efficiency is then defined to quantitatively describe the conversion. The conversion efficiency is strongly frequency dependent and can be significant. With the converted propagating waves from evanescent, sensors at far-field can recapture some localized damage information that is generally possessed in evanescent waves and may have potential application in structural health monitoring.
Roze des Ordons, Amanda; Kassam, Aliya; Simon, Jessica
2017-01-06
Residents are commonly involved in establishing goals of care for hospitalized patients. While education can improve the quality of these conversations, whether and how postgraduate training programs integrate such teaching into their curricula is not well established. The objective of this study was to characterize perceptions of current teaching and assessment of goals of care conversations, and program director interest in associated curricular integration. An electronic survey was sent to all postgraduate program directors at the University of Calgary. Quantitative data was analyzed using descriptive statistics and qualitative comments were analyzed using thematic analysis. The survey response rate was 34% (22/64). Formal goals of care conversation teaching is incorporated into 63% of responding programs, and most commonly involves lectures. Informal teaching occurs in 86% of programs, involving discussion, direct observation and role modeling in the clinical setting. Seventy-three percent of programs assess goals of care conversation skills, mostly in the clinical setting through feedback. Program directors believe that over two-thirds of clinical faculty are prepared to teach goals of care conversations, and are interested in resources to teach and assess goals of care conversations. Themes that emerged include 1) general perceptions, 2) need for teaching, 3) ideas for teaching, and 4) assessment of goals of care conversations. The majority of residency training programs at the University of Calgary incorporate some goals of care conversation teaching and assessment into their curricula. Program directors are interested in resources to improve teaching and assessment of goals of care conversations.
A finite element simulation of biological conversion processes in landfills.
Robeck, M; Ricken, T; Widmann, R
2011-04-01
Landfills are the most common way of waste disposal worldwide. Biological processes convert the organic material into an environmentally harmful landfill gas, which has an impact on the greenhouse effect. After the depositing of waste has been stopped, current conversion processes continue and emissions last for several decades and even up to 100years and longer. A good prediction of these processes is of high importance for landfill operators as well as for authorities, but suitable models for a realistic description of landfill processes are rather poor. In order to take the strong coupled conversion processes into account, a constitutive three-dimensional model based on the multiphase Theory of Porous Media (TPM) has been developed at the University of Duisburg-Essen. The theoretical formulations are implemented in the finite element code FEAP. With the presented calculation concept we are able to simulate the coupled processes that occur in an actual landfill. The model's theoretical background and the results of the simulations as well as the meantime successfully performed simulation of a real landfill body will be shown in the following. Copyright © 2010 Elsevier Ltd. All rights reserved.
The role of discourse in group knowledge construction: A case study of engineering students
NASA Astrophysics Data System (ADS)
Kittleson, Julie M.; Southerland, Sherry A.
2004-03-01
This qualitative study examined the role of discourse (verbal elements of language) and Discourse (nonverbal elements related to the use of language, such as ways of thinking, valuing, and using tools and technologies) in the process of group knowledge construction of mechanical engineering students. Data included interviews, participant observations, and transcripts from lab sessions of a group of students working on their senior design project. These data were analyzed using discourse analysis focusing on instances of concept negotiation, interaction in which multiple people contribute to the evolving conceptual conversation. In this context, despite instructors' attempts to enhance the collaboration of group members, concept negotiation was rare. In an effort to understand this rarity, we identified themes related to an engineering Discourse, which included participants' assumptions about the purpose of group work, the views about effective groups, and their epistemologies and ontologies. We explore how the themes associated with the engineering Discourse played a role in how and when the group engaged in concept negotiation. We found that underlying ideologies and assumptions related to the engineering Discourse played both facilitating and inhibitory roles related to the group's conceptually based interactions.
Petrack, Janina; Jost, Steffen; Boenigk, Jens
2014-01-01
Summary Chrysophyceae, also known as golden algae, contain characteristic, three-dimensional biomineralized silica structures. Their chemical composition and microscopic structure was studied. By high-temperature conversion of the skeleton of Mallomonas caudata and Synura petersenii into elementary silicon by magnesium vapour, nanostructured defined replicates were produced which were clearly seen after removal of the formed magnesium oxide with acid. PMID:24991491
Intermediate Fidelity Closed Brayton Cycle Power Conversion Model
NASA Technical Reports Server (NTRS)
Lavelle, Thomas M.; Khandelwal, Suresh; Owen, Albert K.
2006-01-01
This paper describes the implementation of an intermediate fidelity model of a closed Brayton Cycle power conversion system (Closed Cycle System Simulation). The simulation is developed within the Numerical Propulsion Simulation System architecture using component elements from earlier models. Of particular interest, and power, is the ability of this new simulation system to initiate a more detailed analysis of compressor and turbine components automatically and to incorporate the overall results into the general system simulation.
Li, Yuzhong; Tong, Huiling; Zhuo, Yuqun; Li, Yan; Xu, Xuchang
2007-04-15
Sulfur dioxide (SO2) and trace elements are pollutants derived from coal combustion. This study focuses on the simultaneous removal of S02 and trace arsenic oxide (As2O3) from flue gas by calcium oxide (CaO) adsorption in the moderate temperature range. Experiments have been performed on a thermogravimetric analyzer (TGA). The interaction mechanism between As2O3 and CaO is studied via XRD detection. Calcium arsenate [Ca3(AsO4)2] is found to be the reaction product in the range of 600-1000 degrees C. The ability of CaO to absorb As2O3 increases with the increasing temperature over the range of 400-1000 degrees C. Through kinetics analysis, it has been found that the rate constant of arsenate reaction is much higher than that of sulfate reaction. SO2 presence does not affect the trace arsenic capture either in the initial reaction stage when CaO conversion is relatively low or in the later stage when CaO conversion is very high. The product of sulfate reaction, CaS04, is proven to be able to absorb As2O3. The coexisting CO2 does not weaken the trace arsenic capture either.
UNICON: A Powerful and Easy-to-Use Compound Library Converter.
Sommer, Kai; Friedrich, Nils-Ole; Bietz, Stefan; Hilbig, Matthias; Inhester, Therese; Rarey, Matthias
2016-06-27
The accurate handling of different chemical file formats and the consistent conversion between them play important roles for calculations in complex cheminformatics workflows. Working with different cheminformatic tools often makes the conversion between file formats a mandatory step. Such a conversion might become a difficult task in cases where the information content substantially differs. This paper describes UNICON, an easy-to-use software tool for this task. The functionality of UNICON ranges from file conversion between standard formats SDF, MOL2, SMILES, PDB, and PDBx/mmCIF via the generation of 2D structure coordinates and 3D structures to the enumeration of tautomeric forms, protonation states, and conformer ensembles. For this purpose, UNICON bundles the key elements of the previously described NAOMI library in a single, easy-to-use command line tool.
A chip-scale, telecommunications-band frequency conversion interface for quantum emitters.
Agha, Imad; Ates, Serkan; Davanço, Marcelo; Srinivasan, Kartik
2013-09-09
We describe a chip-scale, telecommunications-band frequency conversion interface designed for low-noise operation at wavelengths desirable for common single photon emitters. Four-wave-mixing Bragg scattering in silicon nitride waveguides is used to demonstrate frequency upconversion and downconversion between the 980 nm and 1550 nm wavelength regions, with signal-to-background levels > 10 and conversion efficiency of ≈ -60 dB at low continuous wave input pump powers (< 50 mW). Finite element simulations and the split-step Fourier method indicate that increased input powers of ≈ 10 W (produced by amplified nanosecond pulses, for example) will result in a conversion efficiency > 25 % in existing geometries. Finally, we present waveguide designs that can be used to connect shorter wavelength (637 nm to 852 nm) quantum emitters with 1550 nm.
Yim, Eunice; O’Connell, Karen E.; St. Charles, Jordan; Petes, Thomas D.
2014-01-01
Gene conversions and crossovers are related products of the repair of double-stranded DNA breaks by homologous recombination. Most previous studies of mitotic gene conversion events have been restricted to measuring conversion tracts that are <5 kb. Using a genetic assay in which the lengths of very long gene conversion tracts can be measured, we detected two types of conversions: those with a median size of ∼6 kb and those with a median size of >50 kb. The unusually long tracts are initiated at a naturally occurring recombination hotspot formed by two inverted Ty elements. We suggest that these long gene conversion events may be generated by a mechanism (break-induced replication or repair of a double-stranded DNA gap) different from the short conversion tracts that likely reflect heteroduplex formation followed by DNA mismatch repair. Both the short and long mitotic conversion tracts are considerably longer than those observed in meiosis. Since mitotic crossovers in a diploid can result in a heterozygous recessive deleterious mutation becoming homozygous, it has been suggested that the repair of DNA breaks by mitotic recombination involves gene conversion events that are unassociated with crossing over. In contrast to this prediction, we found that ∼40% of the conversion tracts are associated with crossovers. Spontaneous mitotic crossover events in yeast are frequent enough to be an important factor in genome evolution. PMID:24990991
Communication and Quality of Care on Palliative Care Units: A Qualitative Study.
Seccareccia, Dori; Wentlandt, Kirsten; Kevork, Nanor; Workentin, Kevin; Blacker, Susan; Gagliese, Lucia; Grossman, Daphna; Zimmermann, Camilla
2015-09-01
Clinician-patient communication is central in palliative care, but it has not been described qualitatively which specific elements of communication are important for high-quality palliative care, particularly in the inpatient setting. Our aim was to identify elements of communication that are central to quality of care and satisfaction with care on palliative care units (PCUs), as described by inpatients, family caregivers, and health care providers. Qualitative interviews with patients/caregivers and focus groups with staff were conducted on four PCUs. Semi-structured interviews and focus groups elicited thoughts about the characteristics of satisfaction with care and quality of care for PCU inpatients and their family caregivers. Data were analyzed using a grounded theory method with an inductive, constant comparison approach; themes were coded to saturation. There were 46 interviews and eight focus groups. Communication was the most prevalent theme regarding satisfaction and quality of care, with five subthemes describing elements important to patients, caregivers, and staff. These included: 1) building rapport with patients and families to build trust and kinship; 2) addressing expectations and explaining goals of care; 3) keeping patients and families informed about the patient's condition; 4) listening actively to validate patients' concerns and individual needs; and 5) providing a safe space for conversations about death and dying. Patients, family caregivers, and health care providers affirmed that communication is a central element of quality of care and family satisfaction on PCUs. The five subthemes identified may serve as a structure for education and for quality improvement tools in palliative care inpatient settings.
Mode conversion in metal-insulator-metal waveguide with a shifted cavity
NASA Astrophysics Data System (ADS)
Wang, Yueke; Yan, Xin
2018-01-01
We propose a method, which is utilized to achieve the plasmonic mode conversion in metal-insulator-metal (MIM) waveguide, theoretically. Our proposed structure is composed of bus waveguides and a shifted cavity. The shifted cavity can choose out a plasmonic mode (a- or s-mode) when it is in Fabry-Perot (FP) resonance. The length of the shifted cavity L is carefully chosen, and our structure can achieve the mode conversion between a- and s-mode in the communication region. Besides, our proposed structure can also achieve plasmonic mode-division multiplexing. All the numerical simulations are carried on by the finite element method to verify our design.
The role of amplitude-to-phase conversion in the generation of oscillator flicker phase noise
NASA Technical Reports Server (NTRS)
Hearn, C. P.
1985-01-01
The role of amplitude-to-phase conversion as a factor in feedback oscillator flicker phase noise is examined. A limiting stage consisting of parallel-connected opposite polarity diodes operating in a circuit environment contining reactance is shown to exhibit amplitude-to-phase conversion. This mechanism coupled with resistive upconversion provides an indirect route for very low frequency flicker noise to be transferred into the phase of an oscillator signal. It is concluded that this effect is more significant in the lower frequency regimes where the onlinear reactances associated with active devices are overwhelmed by linear reactive elements.
Boiler Briquette Coal versus Raw Coal: Part I-Stack Gas Emissions.
Ge, Su; Bai, Zhipeng; Liu, Weili; Zhu, Tan; Wang, Tongjian; Qing, Sheng; Zhang, Junfeng
2001-04-01
Stack gas emissions were characterized for a steam-generating boiler commonly used in China. The boiler was tested when fired with a newly formulated boiler briquette coal (BB-coal) and when fired with conventional raw coal (R-coal). The stack gas emissions were analyzed to determine emission rates and emission factors and to develop chemical source profiles. A dilution source sampling system was used to collect PM on both Teflon membrane filters and quartz fiber filters. The Teflon filters were analyzed gravimetrically for PM 10 and PM 2.5 mass concentrations and by X-ray fluorescence (XRF) for trace elements. The quartz fiber filters were analyzed for organic carbon (OC) and elemental carbon (EC) using a thermal/optical reflectance technique. Sulfur dioxide was measured using the standard wet chemistry method. Carbon monoxide was measured using an Orsat combustion analyzer. The emission rates of the R-coal combustion (in kg/hr), determined using the measured stack gas concentrations and the stack gas emission rates, were 0.74 for PM 10 , 0.38 for PM 25 , 20.7 for SO 2 , and 6.8 for CO, while those of the BB-coal combustion were 0.95 for PM 10 , 0.30 for PM 2 5 , 7.5 for SO 2 , and 5.3 for CO. The fuel-mass-based emission factors (in g/kg) of the R-coal, determined using the emission rates and the fuel burn rates, were 1.68 for PM 10 , 0.87 for PM 25 , 46.7 for SO 2 , and 15 for CO, while those of the BB-coal were 2.51 for PM 10 , 0.79 for PM 2.5 , 19.9 for SO 2 , and 14 for CO. The task-based emission factors (in g/ton steam generated) of the R-coal, determined using the fuel-mass-based emission factors and the coal/ steam conversion factors, were 0.23 for PM 10 , 0.12 for PM 2.5 , 6.4 for SO 2 , and 2.0 for CO, while those of the BB-coal were 0.30 for PM 10 , 0.094 for PM 2.5 , 2.4 for SO 2 , and 1.7 for CO. PM 10 and PM 2.5 elemental compositions are also presented for both types of coal tested in the study.
Boiler briquette coal versus raw coal: Part I--Stack gas emissions.
Ge, S; Bai, Z; Liu, W; Zhu, T; Wang, T; Qing, S; Zhang, J
2001-04-01
Stack gas emissions were characterized for a steam-generating boiler commonly used in China. The boiler was tested when fired with a newly formulated boiler briquette coal (BB-coal) and when fired with conventional raw coal (R-coal). The stack gas emissions were analyzed to determine emission rates and emission factors and to develop chemical source profiles. A dilution source sampling system was used to collect PM on both Teflon membrane filters and quartz fiber filters. The Teflon filters were analyzed gravimetrically for PM10 and PM2.5 mass concentrations and by X-ray fluorescence (XRF) for trace elements. The quartz fiber filters were analyzed for organic carbon (OC) and elemental carbon (EC) using a thermal/optical reflectance technique. Sulfur dioxide was measured using the standard wet chemistry method. Carbon monoxide was measured using an Orsat combustion analyzer. The emission rates of the R-coal combustion (in kg/hr), determined using the measured stack gas concentrations and the stack gas emission rates, were 0.74 for PM10, 0.38 for PM2.5, 20.7 for SO2, and 6.8 for CO, while those of the BB-coal combustion were 0.95 for PM10, 0.30 for PM2.5, 7.5 for SO2, and 5.3 for CO. The fuel-mass-based emission factors (in g/kg) of the R-coal, determined using the emission rates and the fuel burn rates, were 1.68 for PM10, 0.87 for PM2.5, 46.7 for SO2, and 15 for CO, while those of the BB-coal were 2.51 for PM10, 0.79 for PM2.5, 19.9 for SO2, and 14 for CO. The task-based emission factors (in g/ton steam generated) of the R-coal, determined using the fuel-mass-based emission factors and the coal/steam conversion factors, were 0.23 for PM10, 0.12 for PM2.5, 6.4 for SO2, and 2.0 for CO, while those of the BB-coal were 0.30 for PM10, 0.094 for PM2.5, 2.4 for SO2, and 1.7 for CO. PM10 and PM2.5 elemental compositions are also presented for both types of coal tested in the study.
Conversing as Metaphor of Human Thinking: Is Mind like a Conversation?
Sorsana, Christine; Trognon, Alain
2018-06-01
How can researchers shape their ideas so that they understand the mind better? This theoretical paper discusses the merits of the conversation metaphor as a means of analyzing the human mind. We will develop arguments concerning conversation as i) a situated and distributed activity, ii) a "product" in perpetual construction, and iii) the amount of credence and belief we afford it. Finally, we will advocate for metaphorical tools that promote a more dynamic conceptualization of human thinking.
Thin conformal antenna array for microwave power conversions
NASA Technical Reports Server (NTRS)
Dickinson, R. M. (Inventor)
1978-01-01
A structure of a circularly polarized, thin conformal, antenna array which may be mounted integrally with the skin of an aircraft employs microstrip elliptical elements and interconnecting feed lines spaced from a circuit ground plane by a thin dielectric layer. The feed lines are impedance matched to the elliptical antenna elements by selecting a proper feedpoint inside the periphery of the elliptical antenna elements. Diodes connected between the feed lines and the ground plane rectify the microwave power, and microstrip filters (low pass) connected in series with the feed lines provide dc current to a microstrip bus. Low impedance matching strips are included between the elliptical elements and the rectifying and filtering elements.
Conversion Factors Periodic Table of the Elements Chart of the Nuclides Map of the Nuclides Computer Index of (Atominstitut der Ãsterreichischen Universitäten) Neutron Activation Table of Elements Neutron Scattering at neutronsources.org. The information contained here in the Neutron Scattering Web has been
Sex Differences in Children's Conversation.
ERIC Educational Resources Information Center
Esposito, Anita
1979-01-01
The recorded conversations of 40 preschool children in small groups were analyzed for interruptions, overlaps, lapses, and gaps. Significant differences were found between heterogeneous and homogeneous groups for interruptions, with boys interrupting girls at a two to one ratio. (Author/RL)
2012-04-01
vapor infiltration on erosion and thermal properties of porous carbon/carbon composite on thermal insulation . Carbon, (38):441– 449, 2000. [14] J. Mueller...Thermal Energy Storage and Thermal Electric Conversion 5a. CONTRACT NUMBER In-House 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S...with thermo-acoustic instabilities. Results will be reported on the flame structure, liquid core length and spreading rate, and comparison with data
Power-Conversion Concept Designed for the Jupiter Icy Moons Orbiter
NASA Technical Reports Server (NTRS)
Mason, Lee S.
2004-01-01
The Jupiter Icy Moons Orbiter (JIMO) is a bold new mission being developed by NASA's Office of Space Science under Project Prometheus. JIMO is examining the potential of nuclear electric propulsion (NEP) technology to efficiently deliver scientific payloads to three of Jupiter's moons: Callisto, Ganymede, and Europa. A critical element of the NEP spacecraft is the space reactor power system (SRPS), consisting of the nuclear reactor, power conversion, heat rejection, and power management and distribution (PMAD).
Policy-Based Management Natural Language Parser
NASA Technical Reports Server (NTRS)
James, Mark
2009-01-01
The Policy-Based Management Natural Language Parser (PBEM) is a rules-based approach to enterprise management that can be used to automate certain management tasks. This parser simplifies the management of a given endeavor by establishing policies to deal with situations that are likely to occur. Policies are operating rules that can be referred to as a means of maintaining order, security, consistency, or other ways of successfully furthering a goal or mission. PBEM provides a way of managing configuration of network elements, applications, and processes via a set of high-level rules or business policies rather than managing individual elements, thus switching the control to a higher level. This software allows unique management rules (or commands) to be specified and applied to a cross-section of the Global Information Grid (GIG). This software embodies a parser that is capable of recognizing and understanding conversational English. Because all possible dialect variants cannot be anticipated, a unique capability was developed that parses passed on conversation intent rather than the exact way the words are used. This software can increase productivity by enabling a user to converse with the system in conversational English to define network policies. PBEM can be used in both manned and unmanned science-gathering programs. Because policy statements can be domain-independent, this software can be applied equally to a wide variety of applications.
75 FR 28663 - Government-Owned Inventions, Available for Licensing
Federal Register 2010, 2011, 2012, 2013, 2014
2010-05-21
... Crack Arresting Barrier. NASA Case No. MFS-32605-1-CIP: Neutron Guides and Methods of Fabrication. NASA...-32697-1: Friction Modifier Using Adherent Metallic Multilayered or Mixed Element Layer Conversion...
Conversion events in gene clusters
2011-01-01
Background Gene clusters containing multiple similar genomic regions in close proximity are of great interest for biomedical studies because of their associations with inherited diseases. However, such regions are difficult to analyze due to their structural complexity and their complicated evolutionary histories, reflecting a variety of large-scale mutational events. In particular, conversion events can mislead inferences about the relationships among these regions, as traced by traditional methods such as construction of phylogenetic trees or multi-species alignments. Results To correct the distorted information generated by such methods, we have developed an automated pipeline called CHAP (Cluster History Analysis Package) for detecting conversion events. We used this pipeline to analyze the conversion events that affected two well-studied gene clusters (α-globin and β-globin) and three gene clusters for which comparative sequence data were generated from seven primate species: CCL (chemokine ligand), IFN (interferon), and CYP2abf (part of cytochrome P450 family 2). CHAP is freely available at http://www.bx.psu.edu/miller_lab. Conclusions These studies reveal the value of characterizing conversion events in the context of studying gene clusters in complex genomes. PMID:21798034
Gorsche, Christian; Harikrishna, Reghunathan; Baudis, Stefan; Knaack, Patrick; Husar, Branislav; Laeuger, Joerg; Hoffmann, Helmuth; Liska, Robert
2017-05-02
In photopolymerization reactions, mostly multifunctional monomers are employed, as they ensure fast reaction times and good final mechanical properties of the cured materials. Drawing conclusions about the influence of the components and curing conditions on the mechanical properties of the subsequently formed insoluble networks is challenging. Therefore, an in situ observation of chemical and mechanical characteristics during the photopolymerization reaction is desired. By coupling of an infrared spectrometer with a photorheometer, a broad spectrum of different photopolymerizable formulations can be analyzed during the curing reaction. The rheological information (i.e., time to gelation, final modulus, shrinkage force) can be derived from a parallel plate rheometer equipped with a UV- and IR-translucent window (glass for NIR and CaF 2 window for MIR). Chemical information (i.e., conversion at the gel point and final conversion) is gained by monitoring the decrease of the corresponding IR-peak for the reactive monomer unit (e.g., C═C double bond peak for (meth)acrylates, H-S thiol and C═C double bond peak in thiol-ene systems, C-O epoxy peak for epoxy resins). Depending on the relative concentration of reactive functional groups in the sample volume and the intensity of the IR signal, the conversion can be monitored in the near-infrared region (e.g., acrylate double bonds, epoxy groups) or the MIR region (e.g., thiol signal). Moreover, an integrated Peltier element and external heating hood enable the characterization of photopolymerization reactions at elevated temperatures, which also widens the window of application to resins that are waxy or solid at ambient conditions. By switching from water to heavy water, the chemical conversion during photopolymerization of hydrogel precursor formulations can also be examined. Moreover, this device could also represent an analytical tool for a variety of thermally and redox initiated systems.
Improving Automated Lexical and Discourse Analysis of Online Chat Dialog
2007-09-01
include spelling- and grammar-checking on our word processing software; voice-recognition in our automobiles; and telephone-based conversational agents ...conversational agents can help customers make purchases on-line [3]. In addition, discourse analyzers can automatically separate multiple, interleaved...telephone-based conversational agent needs to know if it was asked a question or tasked to do something. Indeed, Stolcke et al demonstrated that
Van Scoy, Lauren Jodi; Reading, Jean M; Scott, Allison M; Chuang, Cynthia; Levi, Benjamin H; Green, Michael J
2016-11-01
Substantive discussions between loved ones are necessary for effective advance care planning. Although multiple tools are currently in use for promoting conversations, the content and clinical relevance of the conversations they stimulate is unknown. To describe the content and clinical relevance of conversations that occur during a nonfacilitated end-of-life conversation game. Using convenience sampling, we scheduled adult volunteers to participate in an end-of-life conversation game (2-6 individuals per game; n = 68). Participants discussed 20 questions about death, dying, or end-of-life issues. Games lasted up to two hours and were audio-recorded, transcribed, and analyzed using a conventional qualitative content analysis approach to identify emerging themes. Participants (n = 68) were primarily Caucasian (94%), females (68%), with mean age of 51.3 years (SD 0.7). Seventeen games were analyzed. Four primary themes emerged during game conversations: 1) the importance of people, relationships, and the roles played during end-of-life decision making, 2) values, beliefs, and preferences related to end-of-life care and the dying period, 3) considerations about preparing for the aftermath of one's death, and 4) the relevance of stories or experiences for informing one's own end-of-life preferences. Topics discussed during a nonfacilitated end-of-life conversation game are substantive and address important issues for advance care planning. Copyright © 2016 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.
Tortolini, Cristina; Sanzò, Gabriella; Antiochia, Riccarda; Mazzei, Franco; Favero, Gabriele
2017-01-01
Electrochemical biosensors provide an attractive means of analyzing the content of a biological sample due to the direct conversion of a biological event to an electronic signal. The signal transduction and the general performance of electrochemical biosensors are often determined by the surface architectures that connect the sensing element to the biological sample at the nanometer scale. The most common surface modification techniques, the various electrochemical transduction mechanisms, and the choice of the recognition receptor molecules all influence the ultimate sensitivity of the sensor. We show herein a novel electrochemical biosensing platform based on the coupling of two different nanostructured materials (gold nanoparticles and fullerenols) displaying interesting electrochemical features. The use of these nanomaterials improved the electrochemical performance of the proposed biosensor.An application of the nanostructured enzyme-based biosensor has been developed for evaluating the detection of polyphenols either in buffer solution or in real wine samples.
Wolf, Ruth E.; Morman, Suzette A.; Plumlee, Geoffrey S.
2008-01-01
Assessing potential exposures to toxic metals or metalloids such as arsenic and chromium in environmental materials is important in protecting public health. The chemical form of an element in, or released from, a material is also important, since some forms, such as Cr(VI), are more toxic than others, for example, Cr(III). We have used a variety of procedures to assess potential exposures to hexavalent chromium in ash and burned soils from October 2007 southern California wildfires. Synthetic lung-fluid and de-ionized water extractions simulate release in the lungs and potential environmental releases due to rainfall. Extracts were analyzed for specific chromium and arsenic species using HPLC-ICP-MS methodology. Results indicate that the highly oxidizing environment in wildfires promotes some chromium conversion to Cr(VI), and that the caustic alkalinity of ash enhances Cr(VI) release and stability in lung fluids and rainfall.
Preliminary System Analysis of In Situ Resource Utilization for Mars Human Exploration
NASA Technical Reports Server (NTRS)
Rapp, Donald; Andringa, Jason; Easter, Robert; Smith, Jeffrey H .; Wilson, Thomas; Clark, D. Larry; Payne, Kevin
2005-01-01
We carried out a system analysis of processes for utilization of Mars resources to support human exploration of Mars by production of propellants from indigenous resources. Seven ISRU processes were analyzed to determine mass. power and propellant storage volume requirements. The major elements of each process include C02 acquisition, chemical conversion, and storage of propellants. Based on a figure of merit (the ratio of the mass of propellants that must be brought from Earth in a non-ISRU mission to the mass of the ISRU system. tanks and feedstocks that must be brought from Earth for a ISRU mission) the most attractive process (by far); is one where indigenous Mars water is accessible and this is processed via Sabatier/Electrolysis to methane and oxygen. These processes are technically relatively mature. Other processes with positive leverage involve reverse water gas shift and solid oxide electrolysis.
Hognon, Céline; Dupont, Capucine; Grateau, Maguelone; Delrue, Florian
2014-07-01
This study aims at comparing the steam gasification behaviour of two species of algal biomass (Chlamydomonas reinhardtii and Arthrospira platensis) and three species of lignocellulosic biomass (miscanthus, beech and wheat straw). Isothermal experiments were carried out in a thermobalance under chemical regime. Samples had very different contents in inorganic elements, which resulted in different reactivities, with about a factor of 5 between samples. For biomasses with ratio between potassium content and phosphorus and silicon content K/(Si+P) higher than one, the reaction rate was constant during most of the reaction and then slightly increased at high conversion. On the contrary, for biomasses with ratio K/(Si+P) lower than one, the reaction rate decreased along conversion. A simple kinetic model was proposed to predict these behaviours. Copyright © 2014 Elsevier Ltd. All rights reserved.
A reduced-dimensionality approach to uncovering dyadic modes of body motion in conversations.
Gaziv, Guy; Noy, Lior; Liron, Yuvalal; Alon, Uri
2017-01-01
Face-to-face conversations are central to human communication and a fascinating example of joint action. Beyond verbal content, one of the primary ways in which information is conveyed in conversations is body language. Body motion in natural conversations has been difficult to study precisely due to the large number of coordinates at play. There is need for fresh approaches to analyze and understand the data, in order to ask whether dyads show basic building blocks of coupled motion. Here we present a method for analyzing body motion during joint action using depth-sensing cameras, and use it to analyze a sample of scientific conversations. Our method consists of three steps: defining modes of body motion of individual participants, defining dyadic modes made of combinations of these individual modes, and lastly defining motion motifs as dyadic modes that occur significantly more often than expected given the single-person motion statistics. As a proof-of-concept, we analyze the motion of 12 dyads of scientists measured using two Microsoft Kinect cameras. In our sample, we find that out of many possible modes, only two were motion motifs: synchronized parallel torso motion in which the participants swayed from side to side in sync, and still segments where neither person moved. We find evidence of dyad individuality in the use of motion modes. For a randomly selected subset of 5 dyads, this individuality was maintained for at least 6 months. The present approach to simplify complex motion data and to define motion motifs may be used to understand other joint tasks and interactions. The analysis tools developed here and the motion dataset are publicly available.
A reduced-dimensionality approach to uncovering dyadic modes of body motion in conversations
Noy, Lior; Liron, Yuvalal; Alon, Uri
2017-01-01
Face-to-face conversations are central to human communication and a fascinating example of joint action. Beyond verbal content, one of the primary ways in which information is conveyed in conversations is body language. Body motion in natural conversations has been difficult to study precisely due to the large number of coordinates at play. There is need for fresh approaches to analyze and understand the data, in order to ask whether dyads show basic building blocks of coupled motion. Here we present a method for analyzing body motion during joint action using depth-sensing cameras, and use it to analyze a sample of scientific conversations. Our method consists of three steps: defining modes of body motion of individual participants, defining dyadic modes made of combinations of these individual modes, and lastly defining motion motifs as dyadic modes that occur significantly more often than expected given the single-person motion statistics. As a proof-of-concept, we analyze the motion of 12 dyads of scientists measured using two Microsoft Kinect cameras. In our sample, we find that out of many possible modes, only two were motion motifs: synchronized parallel torso motion in which the participants swayed from side to side in sync, and still segments where neither person moved. We find evidence of dyad individuality in the use of motion modes. For a randomly selected subset of 5 dyads, this individuality was maintained for at least 6 months. The present approach to simplify complex motion data and to define motion motifs may be used to understand other joint tasks and interactions. The analysis tools developed here and the motion dataset are publicly available. PMID:28141861
ECUT (Energy Conversion and Utilization Technologies Program). Biocatalysis Project
NASA Technical Reports Server (NTRS)
1986-01-01
Presented are the FY 1985 accomplishments, activities, and planned research efforts of the Biocatalysis Project of the U.S. Department of Energy, Energy Conversion and Utilization Technologies (ECUT) Program. The Project's technical activities were organized as follows: In the Molecular Modeling and Applied Genetics work element, research focused on (1) modeling and simulation studies to establish the physiological basis of high temperature tolerance in a selected enzyme and the catalytic mechanisms of three species of another enzyme, and (2) determining the degree of plasmid amplification and stability of several DNA bacterial strains. In the Bioprocess Engineering work element, research focused on (1) studies of plasmid propagation and the generation of models, (2) developing methods for preparing immobilized biocatalyst beads, and (3) developing an enzyme encapsulation method. In the Process Design and Analysis work element, research focused on (1) further refinement of a test case simulation of the economics and energy efficiency of alternative biocatalyzed production processes, (2) developing a candidate bioprocess to determine the potential for reduced energy consumption and facility/operating costs, and (3) a techno-economic assessment of potential advancements in microbial ammonia production.
NASA Technical Reports Server (NTRS)
Jalufka, N. W.
1989-01-01
The conversion of laser energy to other, more useful, forms is an important element of any space power transmission system employing lasers. In general the user, at the receiving sight, will require the energy in a form other than laser radiation. In particular, conversion to rocket power and electricity are considered to be two major areas where one must consider various conversion techniques. Three systems (photovoltaic cells, MHD generators, and gas turbines) have been identified as the laser-to-electricity conversion systems that appear to meet most of the criteria for a space-based system. The laser thruster also shows considerable promise as a space propulsion system. At this time one cannot predict which of the three laser-to-electric converters will be best suited to particular mission needs. All three systems have some particular advantages, as well as disadvantages. It would be prudent to continue research on all three systems, as well as the laser rocket thruster. Research on novel energy conversion systems, such as the optical rectenna and the reverse free-electron laser, should continue due to their potential for high payoff.
NASA Astrophysics Data System (ADS)
Happo, Naohisa; Hada, Takuma; Kubota, Atsushi; Ebisu, Yoshihiro; Hosokawa, Shinya; Kimura, Koji; Tajiri, Hiroo; Matsushita, Tomohiro; Hayashi, Kouichi
2018-05-01
Using a graphite crystal analyzer, focused monochromatic fluorescent X-rays can be obtained on an X-ray fluorescence holography (XFH) measurement. To measure the holograms of elements lighter than Ti, we improved a cylindrical-type crystal analyzer and constructed a small C-shaped analyzer. Using the constructed C-shaped analyzer, a Ca Kα hologram of a fluorite single crystal was obtained, from which we reconstructed a clear atomic image. The XFH measurements for the K, Ca, and Sc elements become possible using the presently constructed analyzer.
Conversation Threads Hidden within Email Server Logs
NASA Astrophysics Data System (ADS)
Palus, Sebastian; Kazienko, Przemysław
Email server logs contain records of all email Exchange through this server. Often we would like to analyze those emails not separately but in conversation thread, especially when we need to analyze social network extracted from those email logs. Unfortunately each mail is in different record and those record are not tided to each other in any obvious way. In this paper method for discussion threads extraction was proposed together with experiments on two different data sets - Enron and WrUT..
Advances in engineered microorganisms for improving metabolic conversion via microgravity effects.
Huangfu, Jie; Zhang, Genlin; Li, Jun; Li, Chun
2015-01-01
As an extreme and unique environment, microgravity has significant effects on microbial cellular processes, such as cell growth, gene expression, natural pathways and biotechnological products. Application of microgravity effects to identify the regulatory elements in reengineering microbial hosts will draw much more attention in further research. In this commentary, we discuss the microgravity effects in engineered microorganisms for improving metabolic conversion, including cell growth kinetics, antimicrobial susceptibility, resistance to stresses, secondary metabolites production, recombinant protein production and enzyme activity, as well as gene expression changes. Application of microgravity effects in engineered microorganisms could provide valuable platform for innovative approaches in bioprocessing technology to largely improve the metabolic conversion efficacy of biopharmaceutical products.
Kaplan, Marcia
Regression is a ubiquitous phenomenon in psychodynamic psychotherapy and psychoanalysis, typically part of a reorganization that leads to progression, at least with respect to recruiting elements in the unconscious to consciousness. Regression in patients with conversion disorder (i.e., pseudo-neurological symptoms without an organic basis) is often itself somatic/physical rather than psychic in nature. Psychotherapists working with these patients must be prepared for confusing or frightening forms of regression that should be expected as part of the therapeutic process. In conversion disorder patients with adequate character structure, this regression, when handled effectively by the psychotherapist, ultimately leads to verbalized thoughts and feelings and a gradually strengthening alternative to physically experienced psychic conflict.
NASA Technical Reports Server (NTRS)
Brown, D. H.; Corman, J. C.
1976-01-01
Ten energy conversion systems are defined and analyzed in terms of efficiency. These include: open-cycle gas turbine recuperative; open-cycle gas turbine; closed-cycle gas turbine; supercritical CO2 cycle; advanced steam cycle; liquid metal topping cycle; open-cycle MHD; closed-cycle inert gas MHD; closed-cycle liquid metal MHD; and fuel cells. Results are presented.
Code of Federal Regulations, 2013 CFR
2013-07-01
... mass balance equation. K 98.116(b) Only annual production by product from each EAF (No CEMS). K 98.116... contributed by methane. Y 98.256(f)(7) Only molar volume conversion factor. Y 98.256(f)(10) Only coke burn-off... methane in coking gas. Y 98.256(l)(5) Only molar volume conversion factor. Y 98.256(m)(3) Only total...
NASA Technical Reports Server (NTRS)
Clark, T. B.
1985-01-01
The organic Rankine-cycle (ORC) power conversion assembly was tested. Qualification testing of the electrical transport subsystem was also completed. Test objectives were to verify compatibility of all system elements with emphasis on control of the power conversion assembly, to evaluate the performance and efficiency of the components, and to validate operating procedures. After 34 hours of power generation under a wide range of conditions, the net module efficiency exceeded 18% after accounting for all parasitic losses.
Influence of Molecular Oxygen on Ortho-Para Conversion of Water Molecules
NASA Astrophysics Data System (ADS)
Valiev, R. R.; Minaev, B. F.
2017-07-01
The mechanism of influence of molecular oxygen on the probability of ortho-para conversion of water molecules and its relation to water magnetization are considered within the framework of the concept of paramagnetic spin catalysis. Matrix elements of the hyperfine ortho-para interaction via the Fermi contact mechanism are calculated, as well as the Maliken spin densities on water protons in H2O and O2 collisional complexes. The mechanism of penetration of the electron spin density into the water molecule due to partial spin transfer from paramagnetic oxygen is considered. The probability of ortho-para conversion of the water molecules is estimated by the quantum chemistry methods. The results obtained show that effective ortho-para conversion of the water molecules is possible during the existence of water-oxygen dimers. An external magnetic field affects the ortho-para conversion rate given that the wave functions of nuclear spin sublevels of the water protons are mixed in the complex with oxygen.
Lewandowska, A U; Bełdowska, M; Witkowska, A; Falkowska, L; Wiśniewska, K
2018-08-15
PM1 aerosols were collected at the coastal station in Gdynia between 1st January and 31st December 2012. The main purpose of the study was to determine the variability in concentrations of mercury Hg(p), organic carbon (OC) and elemental carbon (EC) in PM1 aerosols under varying synoptic conditions in heating and non-heating periods. Additionally, sources of origin and bonds of mercury with carbon species were identified. The highest concentrations of Hg(p), OC and EC were found during the heating period. Then all analyzed PM1 components had a common, local origin related to the consumption of fossil fuels for heating purposes under conditions of lower air temperatures and poor dispersion of pollutants. Long periods without precipitation also led to the increase in concentration of all measured PM1 compounds. In heating period mercury correlated well with elemental carbon and primary and secondary organic carbon when air masses were transported from over the land. At that time, the role of transportation was of minor importance. In the non-heating period, the concentration of all analyzed compounds were lower than in the heating period, which could be associated with the reduced influence of combustion processes, higher precipitation and, in the case of mercury, also the evaporation of aerosols at higher air temperatures. However, when air masses were transported from over the sea or from the port/shipyard areas the mercury concentration increased significantly. In the first case higher air humidity, solar radiation and ozone concentration as well as the presence of marine aerosols could further facilitate the conversion of gaseous mercury into particulate mercury and its concentration increase. In the second case Hg(p) could be adsorbed on particles rich in elemental carbon and primary organic carbon emitted from ships. Copyright © 2018 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
DeRogatis, Amy; Honerkamp, Kenneth; McDaniel, Justin; Medine, Carolyn; Nyitray, Vivian-Lee; Pearson, Thomas
2014-01-01
The editor of "Teaching Theology and Religion" facilitated this reflective conversation with five teachers who have extensive experience and success teaching extremely large classes (150 students or more). In the course of the conversation these professors exchange and analyze the effectiveness of several active learning strategies they…
Simply scan--optical methods for elemental carbon measurement in diesel exhaust particulate.
Forder, James A
2014-08-01
This article describes a performance assessment of three optical methods, a Magee Scientific OT21 Transmissometer, a Hach-Lange Microcolor II difference gloss meter, and a combination of an office scanner with Adobe Photoshop software. The optical methods measure filter staining as a proxy for elemental carbon in diesel exhaust particulate (DEP) exposure assessment and the suitability of each as a replacement for the existing Bosch meter optical method. Filters loaded with DEP were produced from air in a non-coal mine and the exhaust gases from a mobile crane. These were measured with each apparatus and then by combustion to obtain a reference elemental carbon value. The results from each apparatus were then plotted against both the Bosch number and reference elemental carbon values. The equations of the best fit lines for these plots were derived, and these gave functions for elemental carbon and Bosch number from the output of each new optical method. For each optical method, the range of DEP loadings which can be measured has been determined, and conversion equations for elemental carbon and Bosch number have been obtained. All three optical methods studied will effectively quantify blackness as a measure of elemental carbon. Of these the Magee Scientific OT21 transmissometer has the best performance. The Microcolor II and scanner/photoshop methods will in addition allow conversion to Bosch number which may be useful if historical Bosch data are available and functions for this are described. The scanner/photoshop method demonstrates a technique to obtain measurements of DEP exposure without the need to purchase specialized instrumentation. © The Author 2014. Published by Oxford University Press on behalf of the British Occupational Hygiene Society.
Chivarzin, M E; Revelsky, I A; Nikoshina, A V; Buldyzkova, A N; Chepeliansky, D A; Revelsky, A I; Buriak, A K
2016-04-01
The fast method of the simultaneous determination of F(-), Cl(-), Br(-) and SO4(2-) anions in the deionized water on the trace level by ion chromatography using thorough cleaning of respective water containers, 10 μM NaHCO3 water solution as eluent, short Metrohm (50 × 4 mm) separation column and a large water volume injection is proposed. Calculated detection limits are 10(-9)-10(-8)% depending on the element. The method for the fast screening of plant oil samples for the total fluorine-, chlorine-, bromine- and sulfur-organic compounds content (calculated for the respective elements) on the trace level is developed. It is based on the high temperature combustion of oil sample in oxygen flow, absorption of the conversion products in deionized water and whole absorbate volume analysis for F(-), Cl(-), Br(-) and SO4(2-) anions, corresponding to the respective elements, using the developed method of these anions analysis by ion chromatography. The samples of soya, olive, sunflower and cotton seed oil were analyzed. The method detection limits (for 1mg sample) were 2 × 10(-6)%, 2 × 10(-6)%, 5 × 10(-6)% and 5 × 10(-6)% for fluorine, chlorine, bromine and sulfur, respectively. The relative standard deviation was ≤ 15%. The method gives the compressed information about the total content of all target and nontarget fluorine-, chlorine-, bromine- and sulfur-organic compounds in plant oils. Copyright © 2015. Published by Elsevier B.V.
Fates of Chemical Elements in Biomass during Its Pyrolysis.
Liu, Wu-Jun; Li, Wen-Wei; Jiang, Hong; Yu, Han-Qing
2017-05-10
Biomass is increasingly perceived as a renewable resource rather than as an organic solid waste today, as it can be converted to various chemicals, biofuels, and solid biochar using modern processes. In the past few years, pyrolysis has attracted growing interest as a promising versatile platform to convert biomass into valuable resources. However, an efficient and selective conversion process is still difficult to be realized due to the complex nature of biomass, which usually makes the products complicated. Furthermore, various contaminants and inorganic elements (e.g., heavy metals, nitrogen, phosphorus, sulfur, and chlorine) embodied in biomass may be transferred into pyrolysis products or released into the environment, arousing environmental pollution concerns. Understanding their behaviors in biomass pyrolysis is essential to optimizing the pyrolysis process for efficient resource recovery and less environmental pollution. However, there is no comprehensive review so far about the fates of chemical elements in biomass during its pyrolysis. Here, we provide a critical review about the fates of main chemical elements (C, H, O, N, P, Cl, S, and metals) in biomass during its pyrolysis. We overview the research advances about the emission, transformation, and distribution of elements in biomass pyrolysis, discuss the present challenges for resource-oriented conversion and pollution abatement, highlight the importance and significance of understanding the fate of elements during pyrolysis, and outlook the future development directions for process control. The review provides useful information for developing sustainable biomass pyrolysis processes with an improved efficiency and selectivity as well as minimized environmental impacts, and encourages more research efforts from the scientific communities of chemistry, the environment, and energy.
NASA Astrophysics Data System (ADS)
Iguchi, Yuki; Sugiyama, Taiki; Inoue, Kazutoshi; Yanagi, Hiroshi
2018-05-01
Tin monosulfide (SnS) is an attractive material for photovoltaic cells because of its suitable band-gap energy, high absorption coefficient, and non-toxic and abundant constituent elements. The primary drawback of this material is the lack of n-type SnS. We recently demonstrated n-type SnS by doping with Cl. However, the Cl-doped n-type SnS bulk ceramics exhibited an odd behavior in which carrier-type conversion but not electron carrier concentration depended on the Cl concentration. In this study, the electron probe microanalysis (EPMA) elemental mapping of Cl-doped SnS revealed continuous homogeneous regions with a relatively low Cl concentration along with the islands of high Cl concentration in which Sn/S is far from unity. The difference between the Cl concentration in the homogeneous region (determined by EPMA) and the bulk Cl concentration (determined by wavelength-dispersive X-ray fluorescence spectroscopy) increased with the increasing Cl doping amount. The carrier concentration and the Hall coefficient clearly depended on the Cl concentration in the homogeneous region. Carrier-type conversion was observed at the Cl concentration of 0.26 at. % (in the homogeneous region).
Feasibility survey of thermoelectric conversion technology using semiconductors
NASA Astrophysics Data System (ADS)
1993-03-01
The paper takes notice to thermoelectric conversion technology using semiconductors and investigates it in a wide range from high temperature to low temperature to study its feasibility. It is found that in Bi-Te alloy elements applicable to a temperature range of around 200(degree)C, some are over 3.5(times)10(sup -3)K(sup -1) in performance index, and performance of the element can be practically improved in the near future. The thermoelectric power generation system using waste heat from the fuel cell power plant, which is 5-6% in conversion efficiency, can generate output more than 100kW and is expected to improve by approximately 1% in plant overall efficiency. The construction cost, however, is around 1.6-1.9 million yen/kW. The thermoelectric power generation plant which is modeled on No.2 generator of Hatchobaru geothermal power plant can generate electric output of 10-12.5MW, which is smaller than that of the conventional geothermal power generation. The construction cost is around 3.2-4.1 million yen/kW. Even if advantage of the system in running cost is considered, attractive systematization seems to be difficult.
Cloud Microphysics Budget in the Tropical Deep Convective Regime
NASA Technical Reports Server (NTRS)
Li, Xiao-Fan; Sui, C.-H.; Lau, K.-M.; Einaudi, Franco (Technical Monitor)
2001-01-01
Cloud microphysics budgets in the tropical deep convective regime are analyzed based on a 2-D cloud resolving simulation. The model is forced by the large-scale vertical velocity and zonal wind and large-scale horizontal advections derived from TOGA COARE for a 20-day period. The role of cloud microphysics is first examined by analyzing mass-weighted mean heat budget and column-integrated moisture budget. Hourly budgets show that local changes of mass-weighted mean temperature and column-integrated moisture are mainly determined by the residuals between vertical thermal advection and latent heat of condensation and between vertical moisture advection and condensation respectively. Thus, atmospheric thermodynamics depends on how cloud microphysical processes are parameterized. Cloud microphysics budgets are then analyzed for raining conditions. For cloud-vapor exchange between cloud system and its embedded environment, rainfall and evaporation of raindrop are compensated by the condensation and deposition of supersaturated vapor. Inside the cloud system, the condensation of supersaturated vapor balances conversion from cloud water to raindrop, snow, and graupel through collection and accretion processes. The deposition of supersaturated vapor balances conversion from cloud ice to snow through conversion and riming processes. The conversion and riming of cloud ice and the accretion of cloud water balance conversion from snow to graupel through accretion process. Finally, the collection of cloud water and the melting of graupel increase raindrop to compensate the loss of raindrop due to rainfall and the evaporation of raindrop.
Ben Abid, Sadreddine; Mzoughi, Zeineb; Attaoui, Mohamed Amine; Talbi, Ghofrane; Arfa, Nafaa; Gharbi, Lassaad; Khalfallah, Mohamed Taher
2014-12-01
feasibility and advantages of laparoscopic approach in performed duodenal ulcer have no longer to be demonstrated. Laparoscopic suture and peritoneal cleaning expose to a conversion rate between 10 and 23%. However less than laparotomy, morbidity of this approach is not absent. This study aim to analyze factors exposing to conversion after laparoscopic approach of perforred duodenal ulcer. We also aim to define the morbidity of this approach and predictive factors of this morbidity Methods: Retrospective descriptive study was conducted referring all cases of perforated duodenal ulcer treated laparoscopically over a period of ten years, running from January 2000 to December 2010. All patients were operated by laparoscopy with or without conversion. We have noted conversion factors. A statistical analysis with logistic regression was performed whenever we have sought to identify independent risk factors for conversion verified as statistically significant in univariante. The significance level was set at 5%. Analytic univariant and multivariant study was performed to analyze morbidity factors. 290 patients were included. The median age was 34ans.T he intervention was conducted completely laparoscopically in 91.4% of cases. The conversion rate was 8.6%. It was selected as a risk factor for conversion: age> 32 years, a known ulcer, progressive pain, renal function failure, a difficult peritoneal lavage and having a chronic ulcer. Postoperative morbidity was 5.1%. Three independent risk factors of surgical complications were selected: renal failure, age> 45 years, and a chronic ulcer appearance. Laparoscopic treatment of perforred duodenal ulcer expose to a conversion risk. Morbidity is certainly less than laparotomy and a better Knowledge of predictif's morbidity factors become necessary for a better management of this disease.
NASA Astrophysics Data System (ADS)
Robinet, Jérémy; Ameijeiras-Mariño, Yolanda; Vanderborght, Jan; Opfergelt, Sophie; Govers, Gerard
2017-04-01
Hydrology plays a major role in controlling biogeochemical fluxes at various scales. Among the various controlling factors of water fluxes at the hillslope or catchment scale, land use change is a direct human effect which has been relatively under-examined despite its potential important impact. The overall objective of this research is therefore to investigate how land use change can affect water fluxes and how these changes may, on their turn, affect biogeochemical fluxes, with a particular focus on silicon (Si) dynamic. We selected two small catchments with contrasting land use (agriculture vs. natural forest) in a subtropical region in the south of Brazil. The conversion of forest to arable land in the agricultural catchment is relatively recent, as deforestation started at the beginning of the 20th century. Stream, pore and groundwater were monitored, sampled and analyzed for major elements concentrations and δ18O. Preliminary results showed that deforestation and agriculture led to an increase in solute export at the catchment outlet, with for example dissolved Si (DSi) concentration and flux two times higher for the agricultural catchment. δ18O and DSi concentration data showed the importance of preferential flow in macropores in the forested catchment, probably because of the high root and low bulk densities. This led to a reduced mobilization of the pore water during rainfall event, contrarily to the agricultural catchment. As a result, there is almost no contribution of this relatively DSi-enriched pool to the river discharge in the forested environment. Those results indicate that the conversion of forest to arable land has had a significant impact on the biogeochemical fluxes, highlighted in this study with observed changes in DSi flux. Those changes could be partially attributed to changes in water fluxes and pathways.
Single-mode annular chirally-coupled core fibers for fiber lasers
NASA Astrophysics Data System (ADS)
Zhang, Haitao; Hao, He; He, Linlu; Gong, Mali
2018-03-01
Chirally-coupled core (CCC) fiber can transmit single fundamental mode and effectively suppresses higher-order mode (HOM) propagation, thus improve the beam quality. However, the manufacture of CCC fiber is complicated due to its small side core. To decrease the manufacture difficulty in China, a novel fiber structure is presented, defined as annular chirally-coupled core (ACCC) fiber, replacing the small side core by a larger side annulus. In this paper, we designed the fiber parameters of this new structure, and demonstrated that the new structure has a similar property of single mode with traditional CCC fiber. Helical coordinate system was introduced into the finite element method (FEM) to analyze the mode field in the fiber, and the beam propagation method (BPM) was employed to analyze the influence of the fiber parameters on the mode loss. Based on the result above, the fiber structure was optimized for efficient single-mode transmission, in which the core diameter is 35 μm with beam quality M2 value of 1.04 and an optical to optical conversion efficiency of 84%. In this fiber, fundamental mode propagates in an acceptable loss, while the HOMs decay rapidly.
Key issues in controlling air pollutants in Dhaka, Bangladesh
NASA Astrophysics Data System (ADS)
Begum, Bilkis A.; Biswas, Swapan K.; Hopke, Philip K.
2011-12-01
Particulate matter (PM) sampling for both coarse and fine fractions was conducted in a semi-residential site (AECD) in Dhaka from February 2005 to December 2006. The samples were analyzed for mass, black carbon (BC), and elemental compositions. The resulting data set were analyzed for sources by Positive Matrix Factorization (EPA-PMF). From previous studies, it is found that, the air quality became worse in the dry winter period compared to the rainy season because of higher particulate matter concentration in the ambient air. Therefore, seasonal source contributions were determined from seasonally segregated data using EPA-PMF modeling so that further policy interventions can be undertaken to improve air quality. From the source apportionment results, it is observed that vehicular emissions and emission from brick kiln are the major contributors to air pollution in Dhaka especially in the dry seasons, while contribution from emissions from metal smelters increases during rainy seasons. The Government of Bangladesh is considering different interventions to reduce the emissions from those sources by adopting conversion of diesel/petrol vehicles to CNG, increasing traffic speed in the city and by introducing green technologies for brick production. However, in order to reduce the transboundary effect it is necessary to take action regionally.
ECUT (Energy Conversion and Utilization Technologies) program: Biocatalysis project
NASA Technical Reports Server (NTRS)
Baresi, Larry
1989-01-01
The Annual Report presents the fiscal year (FY) 1988 research activities and accomplishments, for the Biocatalysis Project of the U.S. Department of Energy, Energy Conversion and Utilization Technologies (ECUT) Division. The ECUT Biocatalysis Project is managed by the Jet Propulsion Laboratory, California Institute of Technology. The Biocatalysis Project is a mission-oriented, applied research and exploratory development activity directed toward resolution of the major generic technical barriers that impede the development of biologically catalyzed commercial chemical production. The approach toward achieving project objectives involves an integrated participation of universities, industrial companies and government research laboratories. The Project's technical activities were organized into three work elements: (1) The Molecular Modeling and Applied Genetics work element includes research on modeling of biological systems, developing rigorous methods for the prediction of three-dimensional (tertiary) protein structure from the amino acid sequence (primary structure) for designing new biocatalysis, defining kinetic models of biocatalyst reactivity, and developing genetically engineered solutions to the generic technical barriers that preclude widespread application of biocatalysis. (2) The Bioprocess Engineering work element supports efforts in novel bioreactor concepts that are likely to lead to substantially higher levels of reactor productivity, product yields and lower separation energetics. Results of work within this work element will be used to establish the technical feasibility of critical bioprocess monitoring and control subsystems. (3) The Bioprocess Design and Assessment work element attempts to develop procedures (via user-friendly computer software) for assessing the energy-economics of biocatalyzed chemical production processes, and initiation of technology transfer for advanced bioprocesses.
ECUT (Energy Conversion and Utilization Technologies) program: Biocatalysis project
NASA Astrophysics Data System (ADS)
Baresi, Larry
1989-03-01
The Annual Report presents the fiscal year (FY) 1988 research activities and accomplishments, for the Biocatalysis Project of the U.S. Department of Energy, Energy Conversion and Utilization Technologies (ECUT) Division. The ECUT Biocatalysis Project is managed by the Jet Propulsion Laboratory, California Institute of Technology. The Biocatalysis Project is a mission-oriented, applied research and exploratory development activity directed toward resolution of the major generic technical barriers that impede the development of biologically catalyzed commercial chemical production. The approach toward achieving project objectives involves an integrated participation of universities, industrial companies and government research laboratories. The Project's technical activities were organized into three work elements: (1) The Molecular Modeling and Applied Genetics work element includes research on modeling of biological systems, developing rigorous methods for the prediction of three-dimensional (tertiary) protein structure from the amino acid sequence (primary structure) for designing new biocatalysis, defining kinetic models of biocatalyst reactivity, and developing genetically engineered solutions to the generic technical barriers that preclude widespread application of biocatalysis. (2) The Bioprocess Engineering work element supports efforts in novel bioreactor concepts that are likely to lead to substantially higher levels of reactor productivity, product yields and lower separation energetics. Results of work within this work element will be used to establish the technical feasibility of critical bioprocess monitoring and control subsystems. (3) The Bioprocess Design and Assessment work element attempts to develop procedures (via user-friendly computer software) for assessing the energy-economics of biocatalyzed chemical production processes, and initiation of technology transfer for advanced bioprocesses.
Landscape composition and configuration in the central highlands of Ethiopia.
Tolessa, Terefe; Senbeta, Feyera; Kidane, Moges
2016-10-01
Landscape dynamics are common phenomenon in the human-dominated environments whereby it can be observed that the composition and configuration between landscape elements change over time. This dynamism brings about habitat loss and fragmentation that can greatly alter ecosystem services at patch, class, and landscape levels. We conducted a study to examine composition and configuration of forested landscape in the central highlands of Ethiopia using satellite images of over a period of four decades, and FRAGSTAT raster dataset was used to analyze fragmentation. Our result showed five land use/land cover (LULC) types in the study area. Cultivated land and settlement land increased at the expense of forestland, shrubland, and grassland. Fragmentation analysis showed the number of patches increased for all LULC types, indicating the level of fragmentation and interspersion. Juxtaposition increased for shrubland, grassland, and cultivated lands and decreased for settlement and forestland resulting in the fragmentation and isolation of patches. The study of LULC along with fragmentation at the landscape level can help improve our understanding of the pace at which conversion of landscape elements is happening and the impacts on ecosystem services as studies of LULC are courser in nature and would not show how each land use is reducing in size, proximity and shape among other things that determine ecosystem services. Such type of studies in rural landscapes are very vital to consider appropriate land management policies for the landscape level by taking into account the interaction between each element for sustainable development. We recommend land managers, conservationists, and land owners for observing the roles of each patch in the matrix to maximize the benefits than focusing on a single element.
Kodnik, Danijela; Winkler, Aldo; Candotto Carniel, Fabio; Tretiach, Mauro
2017-10-01
The aim of this study was to verify whether it is possible to discriminate between the different pollution sources present in a mixed land use area of NE Italy on the basis of the magnetic properties and the element content of lichen transplants. Thalli of Pseudevernia furfuracea were collected in a pristine area of the South-Eastern Alps and exposed for 2months in 40 sites located at the knots of a 700m step grid covering ca. 40km 2 of a mosaic of agricultural, forested, industrial and urban areas. In this way, the samples could be analyzed after a defined period of time, and compared to pre-exposure conditions. The post-exposure element content and the magnetic data substantially agreed, revealing a rather modest anthropogenic impact on the territory, mostly limited to an industrial park. Since the magnetic mineralogy was homogeneous throughout the entire set of samples, with magnetite-like minerals as the main magnetic carriers, it was not possible to discriminate between PM originating from the different pollution sources. The contribution given by the industrial park could be confirmed by the multivariate analysis of the element data set. Conversely, it was possible to assess the low environmental impact of the largest local industry, a cement plant, located outside the industrial park. Notwithstanding the relatively short time of the survey, P. furfuracea was proven to be an effective accumulator for biomagnetic monitoring studies, its magnetic properties being excellent proxies for heavy metal pollution even when the anthropogenic impact on the territory is low. Copyright © 2017 Elsevier B.V. All rights reserved.
The co-definition of self: conversations in virtual reality.
Cantamesse, Matteo
2009-01-01
Conversation analysis can take the form of a qualitative methodology for the exploration of discursive productions, whose main goal is the formulation of hypotheses for reading psychosocial interaction through descriptive models of interlocution. Therefore, in this study, conversations in a shared Virtual Environment have been analyzed in order to understand the specific structure, dynamics, and phenomenology of Virtual Reality effects on the "interactive micro-chains" that constitute the communicative thread of daily experience.
Mineral inversion for element capture spectroscopy logging based on optimization theory
NASA Astrophysics Data System (ADS)
Zhao, Jianpeng; Chen, Hui; Yin, Lu; Li, Ning
2017-12-01
Understanding the mineralogical composition of a formation is an essential key step in the petrophysical evaluation of petroleum reservoirs. Geochemical logging tools can provide quantitative measurements of a wide range of elements. In this paper, element capture spectroscopy (ECS) was taken as an example and an optimization method was adopted to solve the mineral inversion problem for ECS. This method used the converting relationship between elements and minerals as response equations and took into account the statistical uncertainty of the element measurements and established an optimization function for ECS. Objective function value and reconstructed elemental logs were used to check the robustness and reliability of the inversion method. Finally, the inversion mineral results had a good agreement with x-ray diffraction laboratory data. The accurate conversion of elemental dry weights to mineral dry weights formed the foundation for the subsequent applications based on ECS.
Kardaś, Tomasz M; Nejbauer, Michał; Wnuk, Paweł; Resan, Bojan; Radzewicz, Czesław; Wasylczyk, Piotr
2017-02-22
Although new optical materials continue to open up access to more and more wavelength bands where femtosecond laser pulses can be generated, light frequency conversion techniques are still indispensable in filling the gaps on the ultrafast spectral scale. With high repetition rate, low pulse energy laser sources (oscillators) tight focusing is necessary for a robust wave mixing and the efficiency of broadband nonlinear conversion is limited by diffraction as well as spatial and temporal walk-off. Here we demonstrate a miniature third harmonic generator (tripler) with conversion efficiency exceeding 30%, producing 246 fs UV pulses via cascaded second order processes within a single laser beam focus. Designing this highly efficient and ultra compact frequency converter was made possible by full 3-dimentional modelling of propagation of tightly focused, broadband light fields in nonlinear and birefringent media.
NASA Astrophysics Data System (ADS)
Kardaś, Tomasz M.; Nejbauer, Michał; Wnuk, Paweł; Resan, Bojan; Radzewicz, Czesław; Wasylczyk, Piotr
2017-02-01
Although new optical materials continue to open up access to more and more wavelength bands where femtosecond laser pulses can be generated, light frequency conversion techniques are still indispensable in filling the gaps on the ultrafast spectral scale. With high repetition rate, low pulse energy laser sources (oscillators) tight focusing is necessary for a robust wave mixing and the efficiency of broadband nonlinear conversion is limited by diffraction as well as spatial and temporal walk-off. Here we demonstrate a miniature third harmonic generator (tripler) with conversion efficiency exceeding 30%, producing 246 fs UV pulses via cascaded second order processes within a single laser beam focus. Designing this highly efficient and ultra compact frequency converter was made possible by full 3-dimentional modelling of propagation of tightly focused, broadband light fields in nonlinear and birefringent media.
NUCLEAR REACTOR AND THERMIONIC FUEL ELEMENT THEREFOR
Rasor, N.S.; Hirsch, R.L.
1963-12-01
The patent relates to the direct conversion of fission heat to electricity by use of thermionic plasma diodes having fissionable material cathodes, said diodes arranged to form a critical mass in a nuclear reactor. The patent describes a fuel element comprising a plurality of diodes each having a fissionable material cathode, an anode around said cathode, and an ionizable gas therebetween. Provision is made for flowing the gas and current serially through the diodes. (AEC)
Copper-containing zeolite catalysts
Price, G.L.; Kanazirev, V.
1996-12-10
A catalyst useful in the conversion of nitrogen oxides or in the synthesis of nitriles or imines from amines, is formed by preparing an intimate mechanical mixture of a copper (II)-containing species, such as CuO or CuCl{sub 2}, or elemental copper, with a zeolite having a pore mouth comprising 10 oxygen atoms, such as ZSM-5, converting the elemental copper or copper (II) to copper (I), and driving the copper (I) into the zeolite.
Copper-containing zeolite catalysts
Price, Geoffrey L.; Kanazirev, Vladislav
1996-01-01
A catalyst useful in the conversion of nitrogen oxides or in the synthesis of nitriles or imines from amines, formed by preparing an intimate mechanical mixture of a copper (II)-containing species, such as CuO or CuCl.sub.2, or elemental copper, with a zeolite having a pore mouth comprising 10 oxygen atoms, such as ZSM-5, converting the elemental copper or copper (II) to copper (I), and driving the copper (I) into the zeolite.
Low bandgap mid-infrared thermophotovoltaic arrays based on InAs
NASA Astrophysics Data System (ADS)
Krier, A.; Yin, M.; Marshall, A. R. J.; Kesaria, M.; Krier, S. E.; McDougall, S.; Meredith, W.; Johnson, A. D.; Inskip, J.; Scholes, A.
2015-11-01
We demonstrate the first low bandgap thermophotovoltaic (TPV) arrays capable of operating with heat sources at temperatures as low as 345 °C, which is the lowest ever reported. The individual array elements are based on narrow band gap InAs/InAs0.61Sb0.13P0.26 photodiode structures. External power conversion efficiency was measured to be ∼3% from a single element at room temperature, using a black body at 950 °C. Both 25-element and 65-element arrays were fabricated and exhibited a TPV response at different source temperatures in the range 345-950 °C suitable for electricity generation from waste heat and other applications.
Adaptation of a program for nonlinear finite element analysis to the CDC STAR 100 computer
NASA Technical Reports Server (NTRS)
Pifko, A. B.; Ogilvie, P. L.
1978-01-01
The conversion of a nonlinear finite element program to the CDC STAR 100 pipeline computer is discussed. The program called DYCAST was developed for the crash simulation of structures. Initial results with the STAR 100 computer indicated that significant gains in computation time are possible for operations on gloval arrays. However, for element level computations that do not lend themselves easily to long vector processing, the STAR 100 was slower than comparable scalar computers. On this basis it is concluded that in order for pipeline computers to impact the economic feasibility of large nonlinear analyses it is absolutely essential that algorithms be devised to improve the efficiency of element level computations.
FAST Mast Structural Response to Axial Loading: Modeling and Verification
NASA Technical Reports Server (NTRS)
Knight, Norman F., Jr.; Elliott, Kenny B.; Templeton, Justin D.; Song, Kyongchan; Rayburn, Jeffery T.
2012-01-01
The International Space Station s solar array wing mast shadowing problem is the focus of this paper. A building-block approach to modeling and analysis is pursued for the primary structural components of the solar array wing mast structure. Starting with an ANSYS (Registered Trademark) finite element model, a verified MSC.Nastran (Trademark) model is established for a single longeron. This finite element model translation requires the conversion of several modeling and analysis features for the two structural analysis tools to produce comparable results for the single-longeron configuration. The model is then reconciled using test data. The resulting MSC.Nastran (Trademark) model is then extended to a single-bay configuration and verified using single-bay test data. Conversion of the MSC. Nastran (Trademark) single-bay model to Abaqus (Trademark) is also performed to simulate the elastic-plastic longeron buckling response of the single bay prior to folding.
Optimizing Energy Transduction of Fluctuating Signals with Nanofluidic Diodes and Load Capacitors.
Ramirez, Patricio; Cervera, Javier; Gomez, Vicente; Ali, Mubarak; Nasir, Saima; Ensinger, Wolfgang; Mafe, Salvador
2018-05-01
The design and experimental implementation of hybrid circuits is considered allowing charge transfer and energy conversion between nanofluidic diodes in aqueous ionic solutions and conventional electronic elements such as capacitors. The fundamental concepts involved are reviewed for the case of fluctuating zero-average external potentials acting on single pore and multipore membranes. This problem is relevant to electrochemical energy conversion and storage, the stimulus-response characteristics of nanosensors and actuators, and the estimation of the accumulative effects caused by external signals on biological ion channels. Half-wave and full-wave voltage doublers and quadruplers can scale up the transduction between ionic and electronic signals. The network designs discussed here should be useful to convert the weak signals characteristic of the micro and nanoscale into robust electronic responses by interconnecting iontronics and electronic elements. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Piezoelectric energy harvesting computer controlled test bench
NASA Astrophysics Data System (ADS)
Vázquez-Rodriguez, M.; Jiménez, F. J.; de Frutos, J.; Alonso, D.
2016-09-01
In this paper a new computer controlled (C.C.) laboratory test bench is presented. The patented test bench is made up of a C.C. road traffic simulator, C.C. electronic hardware involved in automating measurements, and test bench control software interface programmed in LabVIEW™. Our research is focused on characterizing electronic energy harvesting piezoelectric-based elements in road traffic environments to extract (or "harvest") maximum power. In mechanical to electrical energy conversion, mechanical impacts or vibrational behavior are commonly used, and several major problems need to be solved to perform optimal harvesting systems including, but no limited to, primary energy source modeling, energy conversion, and energy storage. It is described a novel C.C. test bench that obtains, in an accurate and automatized process, a generalized linear equivalent electrical model of piezoelectric elements and piezoelectric based energy store harvesting circuits in order to scale energy generation with multiple devices integrated in different topologies.
Piezoelectric energy harvesting computer controlled test bench.
Vázquez-Rodriguez, M; Jiménez, F J; de Frutos, J; Alonso, D
2016-09-01
In this paper a new computer controlled (C.C.) laboratory test bench is presented. The patented test bench is made up of a C.C. road traffic simulator, C.C. electronic hardware involved in automating measurements, and test bench control software interface programmed in LabVIEW™. Our research is focused on characterizing electronic energy harvesting piezoelectric-based elements in road traffic environments to extract (or "harvest") maximum power. In mechanical to electrical energy conversion, mechanical impacts or vibrational behavior are commonly used, and several major problems need to be solved to perform optimal harvesting systems including, but no limited to, primary energy source modeling, energy conversion, and energy storage. It is described a novel C.C. test bench that obtains, in an accurate and automatized process, a generalized linear equivalent electrical model of piezoelectric elements and piezoelectric based energy store harvesting circuits in order to scale energy generation with multiple devices integrated in different topologies.
Arbitrary spin-to-orbital angular momentum conversion of light.
Devlin, Robert C; Ambrosio, Antonio; Rubin, Noah A; Mueller, J P Balthasar; Capasso, Federico
2017-11-17
Optical elements that convert the spin angular momentum (SAM) of light into vortex beams have found applications in classical and quantum optics. These elements-SAM-to-orbital angular momentum (OAM) converters-are based on the geometric phase and only permit the conversion of left- and right-circular polarizations (spin states) into states with opposite OAM. We present a method for converting arbitrary SAM states into total angular momentum states characterized by a superposition of independent OAM. We designed a metasurface that converts left- and right-circular polarizations into states with independent values of OAM and designed another device that performs this operation for elliptically polarized states. These results illustrate a general material-mediated connection between SAM and OAM of light and may find applications in producing complex structured light and in optical communication. Copyright © 2017, American Association for the Advancement of Science.
NASA Astrophysics Data System (ADS)
Azhariyah, A. S.; Pradyasti, A.; Dianty, A. G.; Bismo, S.
2018-03-01
This research was based on ozone decomposition in industrial environment. Ozone is harmful to human. Therefore, catalysts were made as a mask filter to decompose ozone. Comparison studies of catalyst supports were done using Granular Activated Carbon (GAC), Natural Zeolite (NZ), and Green Sand (GS). GAC showed the highest catalytic activity compared to other supports with conversion of 98%. Meanwhile, the conversion using NZ was only 77% and GS had been just 27%. GAC had the highest catalytic activity because it had the largest pore volume, which is 0.478 cm3/g. So GAC was used as catalyst supports. To have a higher conversion in ozone decomposition, GAC was impregnated with metal oxide as the active site of the catalyst. Active site comparison was made using CuOX and ZnO as the active site. Morphology, composition, and crystal phase were analyzed using SEM-EDX, XRF, and XRD methods. Mask filter, which contained catalysts for ozone decomposition, was tested using a fixed bed reactor at room temperature and atmospheric pressure. The result of conversion was analyzed using iodometric method. CuOX/GAC and ZnO/GAC 2%-w showed the highest catalytic activity and conversion reached 100%. From the durability test, CuOX/GAC 2%-w was better than ZnO/GAC 2%-w because the conversion of ozone to oxygen reached 100% with the lowest conversion was 70% for over eight hours.
Conversational evidence in therapeutic dialogue.
Strong, Tom; Busch, Robbie; Couture, Shari
2008-07-01
Family therapists' participation in therapeutic dialogue with clients is typically informed by evidence of how such dialogue is developing. In this article, we propose that conversational evidence, the kind that can be empirically analyzed using discourse analyses, be considered a contribution to widening psychotherapy's evidence base. After some preliminaries about what we mean by conversational evidence, we provide a genealogy of evaluative practice in psychotherapy, and examine qualitative evaluation methods for their theoretical compatibilities with social constructionist approaches to family therapy. We then move on to examine the notion of accomplishment in therapeutic dialogue given how such accomplishments can be evaluated using conversation analysis. We conclude by considering a number of research and pedagogical implications we associate with conversational evidence.
Zhang, Ke; Tang, Yiwen; Meng, Jinsong; Wang, Ge; Zhou, Han; Fan, Tongxiang; Zhang, Di
2014-11-03
Polarization-sensitive color originates from polarization-dependent reflection or transmission, exhibiting abundant light information, including intensity, spectral distribution, and polarization. A wide range of butterflies are physiologically sensitive to polarized light, but the origins of polarized signal have not been fully understood. Here we systematically investigate the colorful scales of six species of butterfly to reveal the physical origins of polarization-sensitive color. Microscopic optical images under crossed polarizers exhibit their polarization-sensitive characteristic, and micro-structural characterizations clarify their structural commonality. In the case of the structural scales that have deep ridges, the polarization-sensitive color related with scale azimuth is remarkable. Periodic ridges lead to the anisotropic effective refractive indices in the parallel and perpendicular grating orientations, which achieves form-birefringence, resulting in the phase difference of two different component polarized lights. Simulated results show that ridge structures with reflecting elements reflect and rotate the incident p-polarized light into s-polarized light. The dimensional parameters and shapes of grating greatly affect the polarization conversion process, and the triangular deep grating extends the outstanding polarization conversion effect from the sub-wavelength period to the period comparable to visible light wavelength. The parameters of ridge structures in butterfly scales have been optimized to fulfill the polarization-dependent reflection for secret communication. The structural and physical origin of polarization conversion provides a more comprehensive perspective on the creation of polarization-sensitive color in butterfly wing scales. These findings show great potential in anti-counterfeiting technology and advanced optical material design.
Alkaline decomposition of synthetic jarosite with arsenic
2013-01-01
The widespread use of jarosite-type compounds to eliminate impurities in the hydrometallurgical industry is due to their capability to incorporate several elements into their structures. Some of these elements are of environmental importance (Pb2+, Cr6+, As5+, Cd2+, Hg2+). For the present paper, AsO43- was incorporated into the lattice of synthetic jarosite in order to carry out a reactivity study. Alkaline decomposition is characterized by removal of sulfate and potassium ions from the lattice and formation of a gel consisting of iron hydroxides with absorbed arsenate. Decomposition curves show an induction period followed by a conversion period. The induction period is independent of particle size and exponentially decreases with temperature. The conversion period is characterized by formation of a hydroxide halo that surrounds an unreacted jarosite core. During the conversion period in NaOH media for [OH-] > 8 × 10-3 mol L-1, the process showed a reaction order of 1.86, and an apparent activation energy of 60.3 kJ mol-1 was obtained. On the other hand, during the conversion period in Ca(OH)2 media for [OH-] > 1.90 × 10-2 mol L-1, the reaction order was 1.15, and an apparent activation energy of 74.4 kJ mol-1 was obtained. The results are consistent with the spherical particle model with decreasing core and chemical control. PMID:23566061
Habte, Girum; Hwang, In Min; Kim, Jae Sung; Hong, Joon Ho; Hong, Young Sin; Choi, Ji Yeon; Nho, Eun Yeong; Jamila, Nargis; Khan, Naeem; Kim, Kyong Su
2016-12-01
This study was aimed to establish the elemental profiling and provenance of coffee samples collected from eleven major coffee producing regions of Ethiopia. A total of 129 samples were analyzed for forty-five elements using inductively coupled plasma (ICP)-optical emission spectroscopy (OES), ICP-mass spectrometry (MS) and direct mercury analyzer (DMA). Among the macro elements, K showed the highest levels whereas Fe was found to have the lowest concentration values. In all the samples, Ca, K, Mg, P and S contents were statistically significant (p<0.05). Micro elements showed the concentrations order of: Mn>Cu>Sr>Zn>Rb>Ni>B. Contents of the trace elements were lower than the permissible standard values. Inter-regions differentiation by cluster analysis (CA), linear discriminant analysis (LDA) and principal component analysis (PCA) showed that micro and trace elements are the best chemical descriptors of the analyzed coffee samples. Copyright © 2016 Elsevier Ltd. All rights reserved.
Medical Professionals and Parents: A Linguistic Analysis of Communication Across Contexts.
ERIC Educational Resources Information Center
Tannen, Deborah; Wallat, Cynthia
1986-01-01
This study analyzes videotaped conversations between various family members of a child with cerebral palsy and medical professionals. The conversations are examined for information elaboration and condensation, information negotiation, as well as methodological benefits. The medical interviews elicited new information in various contexts and…
3D augmented reality with integral imaging display
NASA Astrophysics Data System (ADS)
Shen, Xin; Hua, Hong; Javidi, Bahram
2016-06-01
In this paper, a three-dimensional (3D) integral imaging display for augmented reality is presented. By implementing the pseudoscopic-to-orthoscopic conversion method, elemental image arrays with different capturing parameters can be transferred into the identical format for 3D display. With the proposed merging algorithm, a new set of elemental images for augmented reality display is generated. The newly generated elemental images contain both the virtual objects and real world scene with desired depth information and transparency parameters. The experimental results indicate the feasibility of the proposed 3D augmented reality with integral imaging.
NASA Astrophysics Data System (ADS)
Junghans, Cornelia; Schmitt, Franz-Josef; Vukojević, Vladana; Friedrich, Thomas
2016-12-01
Fluorescence correlation spectroscopy relies on temporal autocorrelation analysis of fluorescence intensity fluctuations that spontaneously arise in systems at equilibrium due to molecular motion and changes of state that cause changes in fluorescence, such as triplet state transition, photoisomerization and other photophysical transformations, to determine the rates of these processes. The stability of a fluorescent molecule against dark state conversion is of particular concern for chromophores intended to be used as reference tags for comparing diffusion processes on multiple time scales. In this work, we analyzed properties of two fluorescent proteins, the photoswitchable Dreiklang and its parental eGFP, in solvents of different viscosity to vary the diffusion time through the observation volume element by several orders of magnitude. In contrast to eGFP, Dreiklang undergoes a dark-state conversion on the time scale of tens to hundreds of microseconds under conditions of intense fluorescence excitation, which results in artificially shortened diffusion times if the diffusional motion through the observation volume is sufficiently slowed down. Such photophysical quenching processes have also been observed in FCS studies on other photoswitchable fluorescent proteins including Citrine, from which Dreiklang was derived by genetic engineering. This property readily explains the discrepancies observed previously between the diffusion times of eGFP- and Dreiklang-labeled plasma membrane protein complexes.
Calhoun, Aaron W; Rider, Elizabeth A; Peterson, Eleanor; Meyer, Elaine C
2010-09-01
Multi-rater assessment with gap analysis is a powerful method for assessing communication skills and self-insight, and enhancing self-reflection. We demonstrate the use of this methodology. The Program for the Approach to Complex Encounters (PACE) is an interdisciplinary simulation-based communication skills program. Encounters are assessed using an expanded Kalamazoo Consensus Statement Essential Elements Checklist adapted for multi-rater feedback and gap analysis. Data from a representative conversation were analyzed. Likert and forced-choice data with gap analysis are used to assess performance. Participants were strong in Demonstrating Empathy and Providing Closure, and needed to improve Relationship Building, Gathering Information, and understanding the Patient's/Family's Perspective. Participants under-appraised their abilities in Relationship Building, Providing Closure, and Demonstrating Empathy, as well as their overall performance. The conversion of these results into verbal feedback is discussed. We describe an evaluation methodology using multi-rater assessment with gap analysis to assess communication skills and self-insight. This methodology enables faculty to identify undervalued skills and perceptual blind spots, provide comprehensive, data driven, feedback, and encourage reflection. Implementation of graphical feedback forms coupled with one-on-one discussion using the above methodology has the potential to enhance trainee self-awareness and reflection, improving the impact of educational programs. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.
Andrews, T Daniel; Gojobori, Takashi
2004-01-01
The PilE protein is the major component of the Neisseria meningitidis pilus, which is encoded by the pilE/pilS locus that includes an expressed gene and eight homologous silent fragments. The silent gene fragments have been shown to recombine through gene conversion with the expressed gene and thereby provide a means by which novel antigenic variants of the PilE protein can be generated. We have analyzed the evolutionary rate of the pilE gene using the nucleotide sequence of two complete pilE/pilS loci. The very high rate of evolution displayed by the PilE protein appears driven by both recombination and positive selection. Within the semivariable region of the pilE and pilS genes, recombination appears to occur within multiple small sequence blocks that lie between conserved sequence elements. Within the hypervariable region, positive selection was identified from comparison of the silent and expressed genes. The unusual gene conversion mechanism that operates at the pilE/pilS locus is a strategy employed by N. meningitidis to enhance mutation of certain regions of the PilE protein. The silent copies of the gene effectively allow "parallelized" evolution of pilE, thus enabling the encoded protein to rapidly explore a large area of sequence space in an effort to find novel antigenic variants.
An analytical and experimental investigation of flutter suppression via piezoelectric actuation
NASA Technical Reports Server (NTRS)
Heeg, Jennifer
1992-01-01
The objective of this research was to analytically and experimentally study the capabilities of adaptive material plate actuators for suppressing flutter. Piezoelectrics are materials which are characterized by their ability to produce voltage when subjected to a mechanical strain. The converse piezoelectric effect can be utilized to actuate a structure by applying a voltage. For this investigation, a two degree of freedom wind-tunnel model was designed, analyzed, and tested. The model consisted of a rigid wing and a flexible mount system which permitted translational and rotational degrees of freedom. Actuators, made of piezoelectric material were affixed to leaf springs on the mount system. Command signals, applied to the piezoelectric actuators, exerted control over the closed-loop damping and stiffness properties. A mathematical aeroservoelastic model was constructed using finite element and stiffness properties. A mathematical aeroservoelastic model was constructed using finite element methods, laminated plate theory, and aeroelastic analysis tools. A flutter suppression control law was designed, implemented on a digital control computer, and tested to conditions 20 percent above the passive flutter speed of the model. The experimental results represent the first time that adaptive materials have been used to actively suppress flutter. It demonstrates that small, carefully-placed actuating plates can be used effectively to control aeroelastic response.
Snap-through twinkling energy generation through frequency up-conversion
NASA Astrophysics Data System (ADS)
Panigrahi, Smruti R.; Bernard, Brian P.; Feeny, Brian F.; Mann, Brian P.; Diaz, Alejandro R.
2017-07-01
A novel experimental energy harvester is investigated for its energy harvesting capability by frequency up-conversion using snap-through structures. In particular, a single-degree-of-freedom (SDOF) experimental energy harvester model is built using a snap-through nonlinear element. The snap-through dynamics is facilitated by the experimental setup of a twinkling energy generator (TEG) consisting of linear springs and attracting cylindrical bar magnets. A cylindrical coil of enamel-coated magnet wire is used as the energy generator. The governing equations are formulated mathematically and solved numerically for a direct comparison with the experimental results. The experimental TEG and the numerical simulation results show 25-fold frequency up-conversion and the power harvesting capacity of the SDOF TEG.
For-profit conversion of Blue Cross plans: public benefit or public harm?
Hall, Mark A; Conover, Christopher J
2006-01-01
Conversions of Blue Cross plans to for-profit status have the potential to remake the corporate landscape of health care finance. Absent regulatory intervention, current trends could easily result in more than half of Blue Cross subscribers being in for-profit plans, a phenomenon far more significant than the conversion of nonprofit hospitals. Therefore, regulators' deliberations over conversion proposals are beginning to focus on the health policy impacts. This chapter surveys the full range of health policy implications by analyzing all existing studies of Blue Cross conversions and reporting on the authors' own case studies of conversion impacts. These studies conclude that conversions have not caused major negative impacts on the availability or accessibility of health care in the states in which conversions have occurred so far. However, a great deal of uncertainty exists about the actual effects of previous conversions, and each state is unique; therefore, even if the historical record were clear, it is difficult to predict with great certainty what the actual effects will be in another state undergoing a Blue conversion.
Piscopo, Sara-Pier; Drouin, Guy
2014-05-01
Gene conversions are nonreciprocal sequence exchanges between genes. They are relatively common in Saccharomyces cerevisiae, but few studies have investigated the evolutionary fate of gene conversions or their functional impacts. Here, we analyze the evolution and impact of gene conversions between the two genes encoding 2-deoxyglucose-6-phosphate phosphatase in S. cerevisiae, Saccharomyces paradoxus and Saccharomyces mikatae. Our results demonstrate that the last half of these genes are subject to gene conversions among these three species. The greater similarity and the greater percentage of GC nucleotides in the converted regions, as well as the absence of long regions of adjacent common converted sites, suggest that these gene conversions are frequent and occur independently in all three species. The high frequency of these conversions probably result from the fact that they have little impact on the protein sequences encoded by these genes.
ERIC Educational Resources Information Center
Young, Richard, Ed.; He, Agnes Weiyun, Ed.
Papers on second language oral proficiency testing include: "Language Proficiency Interviews: A Discourse Approach" (Agnes Weiyun He, Richard Young); "Re-Analyzing the OPI: How Much Does It Look Like Natural Conversation?" (Marysia Johnson, Andrea Tyler); "Evaluating Learner Interactional Skills: Conversation at the Micro…
Evaluating Energy Conversion Efficiency
NASA Technical Reports Server (NTRS)
Byvik, C. E.; Smith, B. T.; Buoncristiani, A. M.
1983-01-01
Devices that convert solar radiation directly into storable chemical or electrical energy, have characteristic energy absorption spectrum; specifically, each of these devices has energy threshold. The conversion efficiency of generalized system that emcompasses all threshold devices is analyzed, resulting in family of curves for devices of various threshold energies operating at different temperatures.
Cooperative Catalog Conversion Study. Final Report.
ERIC Educational Resources Information Center
Peat, Marwick, Mitchell and Co., Washington, DC.
Cost estimates provided by cataloging vendors during January 1981 are analyzed to identify the costs of catalog conversion options and alternatives to the card catalog for six Minnesota regional library systems. Following an executive summary of the study is a discussion of its background, scope, objectives, data gathering methodology, and…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-12-27
... Meat processing facilities. 311411 Frozen fruit, juice, and vegetable manufacturing facilities. 311421... volume conversion factor. Y 98.256(m)(3) Only total quantity of crude oil plus the quantity of...
Removal of introduced inorganic content from chipped forest residues via air classification
Lacey, Jeffrey A.; Aston, John E.; Westover, Tyler L.; ...
2015-08-04
Inorganic content in biomass decreases the efficiency of conversion processes, especially thermochemical conversions. The combined concentrations of specific ash forming elements are the primary attributes that cause pine residues to be considered a degraded energy conversion feedstock, as compared to clean pine. Air classification is a potentially effective and economical tool to isolate high inorganic content biomass fractions away from primary feedstock sources to reduce their ash content. In this work, loblolly pine forest residues were air classified into 10 fractions whose ash content and composition were measured. Ash concentrations were highest in the lightest fractions (5.8–8.5 wt%), and inmore » a heavy fraction of the fines (8.9–15.1 wt%). The removal of fractions with high inorganic content resulted in a substantial reduction in the ash content of the remaining biomass in forest thinnings (1.69–1.07 wt%) and logging residues (1.09–0.68 wt%). These high inorganic content fractions from both forest residue types represented less than 7.0 wt% of the total biomass, yet they contained greater than 40% of the ash content by mass. Elemental analysis of the air classified fractions revealed the lightest fractions were comprised of high concentrations of soil elements (silicon, aluminum, iron, sodium, and titanium). However, the elements of biological origin including calcium, potassium, magnesium, sulfur, manganese, and phosphorous were evenly distributed throughout all air classified fractions, making them more difficult to isolate into fractions with high mineral concentrations. Under the conditions reported in this study, an economic analysis revealed air classification could be used for ash removal for as little as $2.23 per ton of product biomass. As a result, this study suggests air classification is a potentially attractive technology for the removal of introduced soil minerals from pine forest residues.« less
A Reload and Startup Plan for and #8233;Conversion of the NIST Research Reactor
DOE Office of Scientific and Technical Information (OSTI.GOV)
Diamond, D. J.; Varuttamaseni, A.
The National Institute of Standards and Technology operates a 20 MW research reactor for neutron-based research. The heavy-water moderated and cooled reactor is fueled with high-enriched uranium (HEU) but a program to convert the reactor to low-enriched uranium (LEU) fuel is underway. Among other requirements, a reload and startup test plan must be submitted to the U.S. Nuclear Regulatory Commission (NRC) for their approval. The NRC provides guidance for what should be in the plan to ensure that the licensee has sufficient information to operate the reactor safely. Hence, a plan has been generated consisting of two parts.The reload portionmore » of the plan specifies the fuel management whereby initially only two LEU fuel elements are in the core for eight fuel cycles. This is repeated until a point when the optimum approach is to place four fresh LEU elements into the reactor each cycle. This final transition is repeated and after eight cycles the reactor is completely fueled with LEU. By only adding two LEU fuel elements initially, the plan allows for the consumption of HEU fuel elements that are expected to be in storage at the time of conversion and provides additional qualification of production LEU fuel under actual operating conditions. Because the reload is to take place over many fuel cycles, startup tests will be done at different stages of the conversion. The tests, to be compared with calculations to show that the reactor will operate as planned, are the measurement of critical shim arm position and shim arm and regulating rod reactivity worths. An acceptance criterion for each test is specified based on technical specifications that relate to safe operation. Additional tests are being considered that have less safety significance but may be of interest to bolster the validation of analysis tools.« less
A reload and startup plan for conversion of the NIST research reactor
DOE Office of Scientific and Technical Information (OSTI.GOV)
D. J. Diamond
The National Institute of Standards and Technology operates a 20 MW research reactor for neutron-based research. The heavy-water moderated and cooled reactor is fueled with high-enriched uranium (HEU) but a program to convert the reactor to low-enriched uranium (LEU) fuel is underway. Among other requirements, a reload and startup test plan must be submitted to the U.S. Nuclear Regulatory Commission (NRC) for their approval. The NRC provides guidance for what should be in the plan to ensure that the licensee has sufficient information to operate the reactor safely. Hence, a plan has been generated consisting of two parts. The reloadmore » portion of the plan specifies the fuel management whereby initially only two LEU fuel elements are in the core for eight fuel cycles. This is repeated until a point when the optimum approach is to place four fresh LEU elements into the reactor each cycle. This final transition is repeated and after eight cycles the reactor is completely fueled with LEU. By only adding two LEU fuel elements initially, the plan allows for the consumption of HEU fuel elements that are expected to be in storage at the time of conversion and provides additional qualification of production LEU fuel under actual operating conditions. Because the reload is to take place over many fuel cycles, startup tests will be done at different stages of the conversion. The tests, to be compared with calculations to show that the reactor will operate as planned, are the measurement of critical shim arm position and shim arm and regulating rod reactivity worths. An acceptance criterion for each test is specified based on technical specifications that relate to safe operation. Additional tests are being considered that have less safety significance but may be of interest to bolster the validation of analysis tools.« less
dc analysis and design of zero-voltage-switched multi-resonant converters
NASA Astrophysics Data System (ADS)
Tabisz, Wojciech A.; Lee, Fred C.
Recently introduced multiresonant converters (MRCs) provide zero-voltage switching (ZVS) of both active and passive switches and offer a substantial reduction of transistor voltage stress and an increase of load range, compared to their quasi-resonant converter counterparts. Using the resonant switch concept, a simple, generalized analysis of ZVS MRCs is presented. The conversion ratio and voltage stress characteristics are derived for basic ZVS MRCs, including buck, boost, and buck/boost converters. Based on the analysis, a design procedure that optimizes the selection of resonant elements for maximum conversion efficiency is proposed.
Electro-optic harmonic conversion to switch a laser beam out of a cavity
Haas, Roger A.; Henesian, Mark A.
1987-01-01
The invention is a switch to permit a laser beam to escape a laser cavity through the use of an externally applied electric field across a harmonic conversion crystal. Amplification takes place in the laser cavity, and then the laser beam is switched out by the laser light being harmonically converted with dichroic or polarization sensitive elements present to alter the optical path of the harmonically converted laser light. Modulation of the laser beam can also be accomplished by varying the external electric field.
Up-conversion media on basis single crystals BaY2F8 for UV and VUV solid state lasers
NASA Astrophysics Data System (ADS)
Pushkar, A. A.; Ouvarova, T. V.; Molchanov, V. N.
2007-04-01
Crystal BaY IIF 8 represents the big interest as the perspective active media for lasers ultra-violet (UV) and vacuumultra- violet (VUV) regions. For the decision of problems with solarization this media and a choice of sources pump it is offered to use up-conversion mechanisms pump with activators from rare-earth elements (RE). We have developed technology of grown of oriented monocrystals BaY IIF 8, have defined influence of orientation on growth rate and quality ofthe received monocrystals.
Fazal, Irfan; Yilmaz, Omer; Nuccio, Scott; Zhang, Bo; Willner, Alan E; Langrock, Carsten; Fejer, Martin M
2007-08-20
10 Gb/s non-return-to-zero (NRZ) on-off keyed (OOK) optical data packets are synchronized and time-multiplexed using a 26-ns tunable all-optical delay line. The delay element is based on wavelength conversion in periodically poled lithium niobate (PPLN) waveguides, inter-channel chromatic dispersion in dispersion compensating fiber (DCF) and intra-channel dispersion compensation with a chirped fiber Bragg grating (FBG). Delay reconfiguration time is measured to be less than 300 ps.
NASA Technical Reports Server (NTRS)
Buoncristiani, A. M.; Smith, B. T.; Byvik, C. E.
1982-01-01
Using general thermodynamic arguments, we analyze the conversion of the energy contained in the radiation from a blackbody to useful work by a quantum system. We show that the energy available for conversion is bounded above by the change in free energy in the incident and reradiated fields and that this free energy change depends upon the temperature of the receiving device. Universal efficiency curves giving the ultimate thermodynamic conversion efficiency of the quantum system are presented in terms of the blackbody temperature and the temperature and threshold energy of the quantum system. Application of these results is made to a variety of systems including biological photosynthetic, photovoltaic, and photoelectrochemical systems.
Development of Support Service for Prevention and Recovery from Dementia and Science of Lethe
NASA Astrophysics Data System (ADS)
Otake, Mihoko
Purpose of this study is to explore service design method through the development of support service for prevention and recovery from dementia towards science of lethe. We designed and implemented conversation support service via coimagination method based on multiscale service design method, both were proposed by the author. Multiscale service model consists of tool, event, human, network, style and rule. Service elements at different scales are developed according to the model. Interactive conversation supported by coimagination method activates cognitive functions so as to prevent progress of dementia. This paper proposes theoretical bases for science of lethe. Firstly, relationship among coimagination method and three cognitive functions including division of attention, planning, episodic memory which decline at mild cognitive imparement. Secondly, thought state transition model during conversation which describes cognitive enhancement via interactive communication. Thirdly, Set Theoretical Measure of Interaction is proposed for evaluating effectiveness of conversation to cognitive enhancement. Simulation result suggests that the ideas which cannot be explored by each speaker are explored during interactive conversation. Finally, coimagination method compared with reminiscence therapy and its possibility for collaboration is discussed.
Yin, Sudong; Dolan, Ryan; Harris, Matt; Tan, Zhongchao
2010-05-01
In this study, cattle manure was converted to bio-oil by subcritical hydrothermal liquefaction in the presence of NaOH. The effects of conversion temperature, process gas, initial conversion pressure, residence time and mass ratio of cattle manure to water on the bio-oil yield were studied. The bio-oil was characterized in terms of elemental composition, higher heating value, ultraviolet-visible (UV/Vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). Results showed that the bio-oil yield depended on the conversion temperature and the process gas. Higher initial conversion pressure, longer residence time and larger mass ratio of cattle manure to water, however, had negative impacts on the bio-oil yield. The higher heating value of bio-oil was 35.53MJ/kg on average. The major non-polar components of bio-oil were toluene, ethyl benzene and xylene, which are components of crude oil, gasoline and diesel. Copyright 2010 Elsevier Ltd. All rights reserved.
NASA Technical Reports Server (NTRS)
Maahs, H. G.
1983-01-01
Results are presented from a laboratory study of the kinetics of the S(IV)-O3 reaction in aqueous solution, including measurements of the effects of UV radiation, dissolved transition metals, and an antioxidant (hydroquinone) on the rate. On the basis of the results, relative rates of S(IV) conversion by O3 in tropospheric cloud water are compared with those predicted for H2O2 and for O2. The reaction mechanism is discussed, with an outline given of the elements of a possible reaction scheme. Application of the rate constants obtained to SO2 conversion in cloud water predicts conversion rates by ozone to be competitive with those by H2O2 at pH above about 4.5 and to dominate at pH above about 5.5. It is pointed out that since these pH's are typical for nonurban tropospheric cloud water, ozone is a potentially important contributor to the overall oxidative conversion of SO2 to sulfate in the nonurban troposphere.
Ten Essential Concepts for Remediation in Mathematics.
ERIC Educational Resources Information Center
Roseman, Louis
1985-01-01
Ten crucial mathematical concepts with which errors are made are listed, with methods used to teach them to high school students. The concepts concern order, place values, inverse operations, multiplication and division, remainders, identity elements, fractions, conversions, decimal points, and percentages. (MNS)
NASA Technical Reports Server (NTRS)
Marr, R. L.; Sambell, K. W.; Neal, G. T.
1973-01-01
Stability and control tests of a scale model of a tilt rotor research aircraft were conducted. The characteristics of the model for hover, low speed, and conversion flight were analyzed. Hover tests were conducted in a rotor whirl cage. Helicopter and conversion tests were conducted in a low speed wind tunnel. Data obtained from the tests are presented as tables and graphs. Diagrams and illustrations of the test equipment are provided.
Setting up virgin stress conditions in discrete element models.
Rojek, J; Karlis, G F; Malinowski, L J; Beer, G
2013-03-01
In the present work, a methodology for setting up virgin stress conditions in discrete element models is proposed. The developed algorithm is applicable to discrete or coupled discrete/continuum modeling of underground excavation employing the discrete element method (DEM). Since the DEM works with contact forces rather than stresses there is a need for the conversion of pre-excavation stresses to contact forces for the DEM model. Different possibilities of setting up virgin stress conditions in the DEM model are reviewed and critically assessed. Finally, a new method to obtain a discrete element model with contact forces equivalent to given macroscopic virgin stresses is proposed. The test examples presented show that good results may be obtained regardless of the shape of the DEM domain.
Setting up virgin stress conditions in discrete element models
Rojek, J.; Karlis, G.F.; Malinowski, L.J.; Beer, G.
2013-01-01
In the present work, a methodology for setting up virgin stress conditions in discrete element models is proposed. The developed algorithm is applicable to discrete or coupled discrete/continuum modeling of underground excavation employing the discrete element method (DEM). Since the DEM works with contact forces rather than stresses there is a need for the conversion of pre-excavation stresses to contact forces for the DEM model. Different possibilities of setting up virgin stress conditions in the DEM model are reviewed and critically assessed. Finally, a new method to obtain a discrete element model with contact forces equivalent to given macroscopic virgin stresses is proposed. The test examples presented show that good results may be obtained regardless of the shape of the DEM domain. PMID:27087731
NASA Astrophysics Data System (ADS)
Sharangovich, Sergey N.; Semkin, Artem O.
2017-12-01
In this work a theoretical model of the holographic formation of the polarization diffractive optical elements for the transformation of Gaussian light beams into Bessel-like ones in polymer-dispersed liquid crystals (PDLC) is developed. The model is based on solving the equations of photo-induced Fredericks transition processes for polarization diffractive elements formation by orthogonally polarized light beams with inhomogeneous amplitude and phase profiles. The results of numerical simulation of the material's dielectric tensor changing due to the structure's formation process are presented for various recording beams' polarization states. Based on the results of numerical simulation, the ability to form the diffractive optical elements for light beams transformation by the polarization holography methods is shown.
NASA Astrophysics Data System (ADS)
Dasgupta, Arati
2015-11-01
Designing high fluence photon sources above 10 keV are a challenge for High Energy Density plasmas. This has motivated radiation source development investigations of Kr with K-shell energies around 13 keV. Recent pulsed power driven gas-puff experiments on the refurbished Z machine at Sandia have produced intense X-rays in the multi-keV photon energy range. K-shell radiative yields and efficiencies are very high for Ar, but rapidly decrease for higher atomic number (ZA) elements such as Kr. It has been suggested that an optimum exists corresponding to a trade-off between the increase of photon energy for higher ZA elements and the corresponding fall off in radiative power. However the conversion efficiency on NIF, where the drive, energy deposition process, and target dynamics are different, does not fall off with higher ZA as rapidly as on Z. We have developed detailed atomic structure and collisional data for the full K-, L- and partial M-shell of Kr using the Flexible Atomic Code (FAC). Our non-LTE atomic model includes all collisional and recombination processes, including state-specific dielectronic recombination (DR), that significantly affect ionization balance and spectra of Kr plasmas at the temperatures and densities of concern. The model couples ionization physics, radiation production and transport, and magnetohydrodynamics. In this talk, I will give a detailed description of the model and discuss 1D Kr simulations employing a multifrequency radiation transport scheme. Synthetic K- and L-shell spectra will be compared with available experimental data. This talk will analyze experimental data indicative of the differences between Z and NIF experimental data and discuss how they affect the K-shell radiative output of Kr plasma. Work supported by DOE/NNSA.
A Coding System for Analysing a Spoken Text Database.
ERIC Educational Resources Information Center
Cutting, Joan
1994-01-01
This paper describes a coding system devised to analyze conversations of graduate students in applied linguistics at Edinburgh University. The system was devised to test the hypothesis that as shared knowledge among conversation participants grows, the textual density of in-group members has more cues than that of strangers. The informal…
"He Said What?!" Constructed Dialogue in Various Interface Modes
ERIC Educational Resources Information Center
Young, Lesa; Morris, Carla; Langdon, Clifton
2012-01-01
This study analyzes the manifestation of constructed dialogue in ASL narratives as dependent on the interface mode (i.e., face-to-face conversation, electronic conversation over videophone, and vlog monologues). Comparisons of eye gaze over three interface modes shows how aspects of constructed dialogue are altered to fit the communication mode.…
ERIC Educational Resources Information Center
Rosemberg, Celia Renata; Alam, Florencia; Stein, Alejandra
2014-01-01
The study analyzed the conversational exchanges through which child tutors mediated literacy abilities and knowledge with young children in the framework of the project "From Child to Child: A Tutor-Child Literacy Program," that is being conducted in Buenos Aires, Argentina. The analysis considered the conversational moves deployed by…
A Conversation with Edwin Shneidman
ERIC Educational Resources Information Center
Pestian, John
2010-01-01
This article is a transcript of a conversation that took place with Edwin Shneidman, PhD, on August 19, 2008. Recent advances in machine learning, particularly neurocognitive computing, have provided a fresh approach to the idea of using computers to analyze the language of the suicidal person. Here this notion and many others are discussed.
ERIC Educational Resources Information Center
Tscholl, Michael; Lindgren, Robb
2016-01-01
This research investigates the social learning affordances of a room-sized, immersive, and interactive augmented reality simulation environment designed to support children's understanding of basic physics concepts in a science center. Conversations between 97 parent-child pairs were analyzed in relation to categories of talk through which…
Children's Sociometric Membership Group and Computer-Supported Interaction in School Settings
ERIC Educational Resources Information Center
Koivusaari, Ritva
2004-01-01
This study analyzed what kind of role sociometric status has in non-real time computer conversations. Computer-supported conversations were investigated by using two local area networks. Participants were 52 9 to 10-year-old schoolchildren selected from three sociometric strata: rejected, average, and popular. Children's preferred friends, school…
ERIC Educational Resources Information Center
Moeschler, Jacques
1981-01-01
Analyzes the strategies employed in terminating conversational exchanges, with particular attention to argumentative sequences. Examines the features that distinguish these sequences from those that have a transactional character, and discusses the patterns of verbal interaction attendant to negative responses. Societe Nouvelle Didier Erudition,…
Restarts in Conversation and Literature.
ERIC Educational Resources Information Center
Person, Raymond F., Jr.
1996-01-01
Analyzes restarts, a common feature of conversation, in literary discourse. The term "restart" refers to the repetition of a word or words within an utterance by the same speaker. Restarts in literary discourse are of two types: (1) those produced by the characters in their "real" narrative world and (2) those produced by the narrators themselves.…
Border Pedagogy Cafes: Grassroots Conversations that Matter
ERIC Educational Resources Information Center
Necochea, Juan; Cline, Zulmara
2008-01-01
This exploratory study uses qualitative methods to analyze the impact of conversations in the Border Pedagogy "Cafes" on more than 500 binational educators from the Tijuana/San Diego area on the U.S.-Mexico border. Four important themes emerged from the analysis that describe the impact of the cafes and offer a strong foundation on which…
ERIC Educational Resources Information Center
Arcidiacono, Francesco; Pontecorvo, Clotilde
2009-01-01
This work studies verbal conflict between parents and preadolescents through analysis of family dinnertime conversations. We move from the assumption that verbal conflict is an educational instrument of interaction and a tool of socialization. The aim of the research is to analyze the participants' strategies in situations of conflict and to…
ERIC Educational Resources Information Center
Amador, Julie M.; Carter, Ingrid S.
2018-01-01
Lesson Study, which assumes multiple variations, is a collaborative method that provides an opportunity for teachers to notice professionally. We analyzed how audible conversational components afforded and constrained the verbalization of professional noticing of a lesson study team. The team, comprised of six prospective teachers, a classroom…
Cogeneration Technology Alternatives Study (CTAS) Volume 5: Analytical approach and results
NASA Technical Reports Server (NTRS)
1980-01-01
Data and information in the area of advanced energy conversion systems for industrial cogeneration applications in the 1985 to 2000 time period are provided. Six current and thirty-six advanced energy conversion systems were defined and combined with appropriate balance of plant equipment. Twenty-six industrial processes were selected from among the high energy consuming industries to serve as a framework for the study. Each conversion system was analyzed as a cogenerator with each industrial plant. Fuel consumption, costs, and environmental intrusion were evaluated and compared to corresponding traditional values. Various cogeneration strategies were analyzed and both topping and bottoming (using industrial by-product heat) applications were included. The advanced energy conversion technologies indicated reduced fuel consumption, costs, and emissions. Typically fuel energy savings of 10 to 25 percent were predicted compared to traditional on site furnaces and utility electricity. Gas turbines and combined cycles indicated high overall annual cost savings. Steam turbines and gas turbines produced high estimated returns. In some applications, diesels were most efficient. The advanced technologies used coal derived fuels, or coal with advanced fluid bed combustion or on site gasification systems.
Conversion total hip arthroplasty: Primary or revision total hip arthroplasty
Schwarzkopf, Ran; Baghoolizadeh, Mahta
2015-01-01
Total hip arthroplasty (THA) is an increasingly common procedure among elderly individuals. Although conversion THA is currently bundled in a diagnosis related group (DRG) with primary THA, there is a lack of literature supporting this classification and it has yet to be identified whether conversion THA better resembles primary or revision THA. This editorial analyzed the intraoperative and postoperative factors and functional outcomes following conversion THA, primary THA, and revision THA to understand whether the characteristics of conversion THA resemble one procedure or the other, or are possibly somewhere in between. The analysis revealed that conversion THA requires more resources both intraoperatively and postoperatively than primary THA. Furthermore, patients undergoing conversion THA present with poorer functional outcomes in the long run. Patients undergoing conversion THA better resemble revision THA patients than primary THA patients. As such, patients undergoing conversion THA should not be likened to patients undergoing primary THA when determining risk stratification and reimbursement rates. Conversion THA procedures should be planned accordingly with proper anticipation of the greater needs both in the operating room, and for in-patient and follow-up care. We suggest that conversion THA be reclassified in the same DRG with revision THA as opposed to primary THA as a step towards better allocation of healthcare resources for conversion hip arthroplasties. PMID:26601055
Ultraefficient homogeneous catalyst for the CO2-to-CO electrochemical conversion.
Costentin, Cyrille; Passard, Guillaume; Robert, Marc; Savéant, Jean-Michel
2014-10-21
A very efficient electrogenerated Fe(0) porphyrin catalyst was obtained by substituting in tetraphenylporphyrin two of the opposite phenyl rings by ortho-, ortho'-phenol groups while the other two are perfluorinated. It proves to be an excellent catalyst of the CO2-to-CO conversion as to selectivity (the CO faradaic yield is nearly quantitative), overpotential, and turnover frequency. Benchmarking with other catalysts, through catalytic Tafel plots, shows that it is the most efficient, to the best of our knowledge, homogeneous molecular catalyst of the CO2-to-CO conversion at present. Comparison with another Fe(0) tetraphenylporphyrin bearing eight ortho-, ortho'-phenol functionalities launches a general strategy where changes in substituents will be designed so as to optimize the operational combination of all catalyst elements of merit.
Open-Cycle Gas Turbine/Steam Turbine Combined Cycles with synthetic fuels from coal
NASA Technical Reports Server (NTRS)
Shah, R. P.; Corman, J. C.
1977-01-01
The Open-Cycle Gas Turbine/Steam Turbine Combined Cycle can be an effective energy conversion system for converting coal to electricity. The intermediate step in this energy conversion process is to convert the coal into a fuel acceptable to a gas turbine. This can be accomplished by producing a synthetic gas or liquid, and by removing, in the fuel conversion step, the elements in the fuel that would be harmful to the environment if combusted. In this paper, two open-cycle gas turbine combined systems are evaluated: one employing an integrated low-Btu gasifier, and one utilizing a semi-clean liquid fuel. A consistent technical/economic information base is developed for these two systems, and is compared with a reference steam plant burning coal directly in a conventional furnace.
Making the improbable probable: communication across models of medical practice.
Buetow, Stephen
2014-06-01
Cooperation and conversation in the public sphere may overcome historical and other barriers to rational argumentation. As an alternative to evidence-based medicine (EBM) and patient-centered care (PCC), the recent development of a modern version of person-centered medicine (PCM) signals an opportunity for a conversational pluralogue to replace parallel monologues between EBM and its critics, and the calls to EBM to debate its critics. This article draws upon elements of Habermas's theory of communicative action in order to suggest the kind of pluralogue that is required for stakeholders in modern medicine to benefit more from publicly conversing with each other than speaking alone or using debate to argue against each other. This reasoned perspective has lessons for all discourse when deep value-based and epistemological differences cannot be easily adjudicated.
Electrocatalysts for carbon dioxide conversion
Masel, Richard I; Salehi-Khojin, Amin
2015-04-21
Electrocatalysts for carbon dioxide conversion include at least one catalytically active element with a particle size above 0.6 nm. The electrocatalysts can also include a Helper Catalyst. The catalysts can be used to increase the rate, modify the selectivity or lower the overpotential of electrochemical conversion of CO.sub.2. Chemical processes and devices using the catalysts also include processes to produce CO, HCO.sup.-, H.sub.2CO, (HCO.sub.2).sup.-, H.sub.2CO.sub.2, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup.-, CH.sub.3COOH, C.sub.2H.sub.6, (COOH).sub.2, or (COO.sup.-).sub.2, and a specific device, namely, a CO.sub.2 sensor.
Noll, James; Gilles, Stewart; Wu, Hsin Wei; Rubinstein, Elaine
2015-01-01
In the United States, total carbon (TC) is used as a surrogate for determining diesel particulate matter (DPM) compliance exposures in underground metal/nonmetal mines. Since TC can be affected by interferences and elemental carbon (EC) is not, one method used to estimate the TC concentration is to multiply the EC concentration from the personal sample by a conversion factor to avoid the influence of potential interferences. Since there is no accepted single conversion factor for all metal/nonmetal mines, one is determined every time an exposure sample is taken by collecting an area sample that represents the TC/EC ratio in the miner's breathing zone and is away from potential interferences. As an alternative to this procedure, this article investigates the relationship between TC and EC from DPM samples to determine if a single conversion factor can be used for all metal/nonmetal mines. In addition, this article also investigates how well EC represents DPM concentrations in Australian coal mines since the recommended exposure limit for DPM in Australia is an EC value. When TC was predicted from EC values using a single conversion factor of 1.27 in 14 US metal/nonmetal mines, 95% of the predicted values were within 18% of the measured value, even at the permissible exposure limit (PEL) concentration of 160 μg/m3 TC. A strong correlation between TC and EC was also found in nine underground coal mines in Australia. PMID:25380085
Comparison of light harmonic generation in Al and Ge consisted silicate materials
NASA Astrophysics Data System (ADS)
Smirnov, Vitaly A.; Vostrikova, Liubov I.
2018-04-01
The silicate materials are perspective for different areas of laser physics and photonics. In this paper the comparison of the nonlinear conversion with the generation of the light harmonic in Al- and Ge-containing silicate materials is presented. The peculiarities of the processes of the light harmonic generation in dependence on the concentrations of the chemical components are discussed and the influences of the additional small inclusion of the elements of fifth group and the rare-earth elements are estimated.
Dissecting engineered cell types and enhancing cell fate conversion via CellNet
Morris, Samantha A.; Cahan, Patrick; Li, Hu; Zhao, Anna M.; San Roman, Adrianna K.; Shivdasani, Ramesh A.; Collins, James J.; Daley, George Q.
2014-01-01
SUMMARY Engineering clinically relevant cells in vitro holds promise for regenerative medicine, but most protocols fail to faithfully recapitulate target cell properties. To address this, we developed CellNet, a network biology platform that determines whether engineered cells are equivalent to their target tissues, diagnoses aberrant gene regulatory networks, and prioritizes candidate transcriptional regulators to enhance engineered conversions. Using CellNet, we improved B cell to macrophage conversion, transcriptionally and functionally, by knocking down predicted B cell regulators. Analyzing conversion of fibroblasts to induced hepatocytes (iHeps), CellNet revealed an unexpected intestinal program regulated by the master regulator Cdx2. We observed long-term functional engraftment of mouse colon by iHeps, thereby establishing their broader potential as endoderm progenitors and demonstrating direct conversion of fibroblasts into intestinal epithelium. Our studies illustrate how CellNet can be employed to improve direct conversion and to uncover unappreciated properties of engineered cells. PMID:25126792
Equivalent circuit modeling of a piezo-patch energy harvester on a thin plate with AC-DC conversion
NASA Astrophysics Data System (ADS)
Bayik, B.; Aghakhani, A.; Basdogan, I.; Erturk, A.
2016-05-01
As an alternative to beam-like structures, piezoelectric patch-based energy harvesters attached to thin plates can be readily integrated to plate-like structures in automotive, marine, and aerospace applications, in order to directly exploit structural vibration modes of the host system without mass loading and volumetric occupancy of cantilever attachments. In this paper, a multi-mode equivalent circuit model of a piezo-patch energy harvester integrated to a thin plate is developed and coupled with a standard AC-DC conversion circuit. Equivalent circuit parameters are obtained in two different ways: (1) from the modal analysis solution of a distributed-parameter analytical model and (2) from the finite-element numerical model of the harvester by accounting for two-way coupling. After the analytical modeling effort, multi-mode equivalent circuit representation of the harvester is obtained via electronic circuit simulation software SPICE. Using the SPICE software, electromechanical response of the piezoelectric energy harvester connected to linear and nonlinear circuit elements are computed. Simulation results are validated for the standard AC-AC and AC-DC configurations. For the AC input-AC output problem, voltage frequency response functions are calculated for various resistive loads, and they show excellent agreement with modal analysis-based analytical closed-form solution and with the finite-element model. For the standard ideal AC input-DC output case, a full-wave rectifier and a smoothing capacitor are added to the harvester circuit for conversion of the AC voltage to a stable DC voltage, which is also validated against an existing solution by treating the single-mode plate dynamics as a single-degree-of-freedom system.
Teeka, Chat; Jalil, Muhammad Arif; Yupapin, Preecha P; Ali, Jalil
2010-12-01
We propose a novel system of the dynamic optical tweezers generated by a dark soliton in the fiber optic loop. A dark soliton known as an optical tweezer is amplified and tuned within the microring resonator system. The required tunable tweezers with different widths and powers can be controlled. The analysis of dark-bright soliton conversion using a dark soliton pulse propagating within a microring resonator system is analyzed. The dynamic behaviors of soliton conversion in add/drop filter is also analyzed. The control dark soliton is input into the system via the add port of the add/drop filter. The dynamic behavior of the dark-bright soliton conversion is observed. The required stable signal is obtained via a drop and throughput ports of the add/drop filter with some suitable parameters. In application, the trapped light/atom and transportation can be realized by using the proposed system.
Aspects of conversational style—linguistic versus behavioral analysis
Hall, Genae A.
1992-01-01
Skinner's functional analysis of verbal behavior has been contrasted with formal linguistic analysis which studies the grammatical structure and “meaning” of verbal response-products, regardless of the circumstances under which they are produced. Nevertheless, it appears that certain areas of linguistic analysis are not entirely structural. In her recent books That's Not What I Meant (1986) and You Just Don't Understand (1990), the linguist Deborah Tannen purports to explain how people exhibit different “conversation styles”—that is, how they speak and achieve effects on listeners in different ways. There are indications, however, that the linguistic model may not be the most functional and precise one that could be used in analyzing conversational style. This paper takes concepts presented in Deborah Tannen's book That's Not What I Meant (1986), analyzes them from a linguistic and a behavioral perspective, and compares the relative utility of the two approaches. PMID:22477048
Aspects of conversational style-linguistic versus behavioral analysis.
Hall, G A
1992-01-01
Skinner's functional analysis of verbal behavior has been contrasted with formal linguistic analysis which studies the grammatical structure and "meaning" of verbal response-products, regardless of the circumstances under which they are produced. Nevertheless, it appears that certain areas of linguistic analysis are not entirely structural. In her recent books That's Not What I Meant (1986) and You Just Don't Understand (1990), the linguist Deborah Tannen purports to explain how people exhibit different "conversation styles"-that is, how they speak and achieve effects on listeners in different ways. There are indications, however, that the linguistic model may not be the most functional and precise one that could be used in analyzing conversational style. This paper takes concepts presented in Deborah Tannen's book That's Not What I Meant (1986), analyzes them from a linguistic and a behavioral perspective, and compares the relative utility of the two approaches.
Irinislimane, Ratiba; Belhaneche-Bensemra, Naima
2012-12-01
Commercial sunflower oil was epoxidized at the laboratory-scale. The epoxidized sunflower oil (ESFO) was modified following the acrylation reaction. Modification was carried out simultaneously using acrylic acid (AA) and triethylamine (TEA). To optimize the reaction conditions, the effects of four temperatures (40, 60, 80, and 100 °C), the ESFO:AA (100:100) ratio, and 0.2% TEA were investigated. The rate of conversion was analyzed with both FT-IR and titration of the oxirane ring. After that, the temperature with the highest conversion was selected and used throughout for all modification reactions. Then, four ratios (100:100, 100:90, 100:80, and 100:75) of ESFO:AA were analyzed at four different concentrations of TEA (0.2, 0.3, 0.4, and 0.5%) to determine the best estimate for both the ESFO:AA ratio and the catalyst concentration. Conversion rate was analyzed using FT-IR spectroscopy by measuring the concentrations of ester, carbonyl, and alcohol groups. Moreover, oxirane-ring concentration was estimated using the titration method (with gentian violet as indicator) and FT-IR spectroscopy (epoxy ring absorptions at 1270 cm(-1) and 877 cm(-1)). Based on conversion yield, the optimum ESFO:AA ratio corresponds to 100:80; the best temperature reaction was at 60 °C, and the best TEA concentration was 0.2%. The critical amounts of reactants needed to reach maximum conversion were established. The final acid value of the acrylated ESFO after washing (pH = 7) was 2.1 mg potassium hydroxide (KOH)·g(-1). All results show that FT-IR spectroscopy is a simple, low-cost, rapid method for investigating the kinetics of a reaction.
Muller, Markus K; Wrann, Simon; Widmer, Jeannette; Klasen, Jennifer; Weber, Markus; Hahnloser, Dieter
2016-09-01
The surgical treatment for perforated peptic ulcers can be safely performed laparoscopically. The aim of the study was to define simple predictive factors for conversion and septic complications. This retrospective case-control study analyzed patients treated with either laparoscopic surgery or laparotomy for perforated peptic ulcers. A total of 71 patients were analyzed. Laparoscopically operated patients had a shorter hospital stay (13.7 vs. 15.1 days). In an intention-to-treat analysis, patients with conversion to open surgery (analyzed as subgroup from laparoscopic approach group) showed no prolonged hospital stay (15.3 days) compared to patients with a primary open approach. Complication and mortality rates were not different between the groups. The statistical analysis identified four intraoperative risk factors for conversion: Mannheim peritonitis index (MPI) > 21 (p = 0.02), generalized peritonitis (p = 0.04), adhesions, and perforations located in a region other than the duodenal anterior wall. We found seven predictive factors for septic complications: age >70 (p = 0.02), cardiopulmonary disease (p = 0.04), ASA > 3 (p = 0.002), CRP > 100 (p = 0.005), duration of symptoms >24 h (p = 0.02), MPI > 21(p = 0.008), and generalized peritonitis (p = 0.02). Our data suggest that a primary laparoscopic approach has no disadvantages. Factors necessitating conversions emerged during the procedure inhibiting a preoperative selection. Factors suggesting imminent septic complications can be assessed preoperatively. An assessment of the proposed parameters may help optimize the management of possible septic complications.
NASA’s Walter Olson poses in the New Energy Conversion Laboratory
1963-07-21
Walter Olson, Chief of the Chemistry and Energy Conversion Division, examines equipment in the new Energy Conversion Laboratory at the National Aeronautics and Space Administration (NASA) Lewis Research Center. The Energy Conversion Laboratory, built in 1961 and 1962, was a modest one-story brick structure with 30,000 square feet of working space. It was used to study fundamental elements pertaining to the conversion of energy into electrical power. The main application for this was space power, but in the 1970s it would also be applied for terrestrial applications. Olson joined the Lewis staff as a fuels and combustion researcher in 1942 and was among a handful or researchers who authored the new laboratory’s first technical report. The laboratory reorganized after the war and Olson was placed in charge of three sections of researchers in the Combustion Branch. They studied combustion and fuels for turbojets, ramjets, and small rockets. In 1950, Olson was named Chief of the entire Fuels and Combustion Research Division. In 1960 Olson was named Chief of the new Chemistry and Energy Conversion Division. It was in this role that Olson advocated for the construction of the Energy Conversion Laboratory. The new division expanded its focus from just fuels and combustion to new sources of energy and power such as solar cells, fuels cells, heat transfer, and thermionics.
Would you tell everyone this? Facebook conversations as health promotion interventions.
Syred, Jonathan; Naidoo, Carla; Woodhall, Sarah C; Baraitser, Paula
2014-04-11
Health promotion interventions on social networking sites can communicate individually tailored content to a large audience. User-generated content helps to maximize engagement, but health promotion websites have had variable success in supporting user engagement. The aim of our study was to examine which elements of moderator and participant behavior stimulated and maintained interaction with a sexual health promotion site on Facebook. We examined the pattern and content of posts on a Facebook page. Google analytics was used to describe the number of people using the page and viewing patterns. A qualitative, thematic approach was used to analyze content. During the study period (January 18, 2010, to June 27, 2010), 576 users interacted 888 times with the site through 508 posts and 380 comments with 93% of content generated by users. The user-generated conversation continued while new participants were driven to the site by advertising, but interaction with the site ceased rapidly after the advertising stopped. Conversations covered key issues on chlamydia and chlamydia testing. Users endorsed testing, celebrated their negative results, and modified and questioned key messages. There was variation in user approach to the site from sharing of personal experience and requesting help to joking about sexually transmitted infection. The moderator voice was reactive, unengaged, tolerant, simplistic, and was professional in tone. There was no change in the moderator approach throughout the period studied. Our findings suggest this health promotion site provided a space for single user posts but not a self-sustaining conversation. Possible explanations for this include little new content from the moderator, a definition of content too narrow to hold the interest of participants, and limited responsiveness to user needs. Implications for health promotion practice include the need to consider a life cycle approach to online community development for health promotion and the need for a developing moderator strategy to reflect this. This strategy should reflect two facets of moderation for online health promotion interventions: (1) unengaged and professional oversight to provide a safe space for discussion and to maintain information quality, and (2) a more engaged and interactive presence designed to maintain interest that generates new material for discussion and is responsive to user requests.
NASA Technical Reports Server (NTRS)
Barrett, Michael J.
2004-01-01
The elements of Brayton technology development emphasize power conversion system risk mitigation. Risk mitigation is achieved by demonstrating system integration feasibility, subsystem/component life capability (particularly in the context of material creep) and overall spacecraft mass reduction. Closed-Brayton-cycle (CBC) power conversion technology is viewed as relatively mature. At the 2-kWe power level, a CBC conversion system Technology Readiness Level (TRL) of six (6) was achieved during the Solar Dynamic Ground Test Demonstration (SD-GTD) in 1998. A TRL 5 was demonstrated for 10 kWe-class CBC components during the development of the Brayton Rotating Unit (BRU) from 1968 to 1976. Components currently in terrestrial (open cycle) Brayton machines represent TRL 4 for similar uses in 100 kWe-class CBC space systems. Because of the baseline component and subsystem technology maturity, much of the Brayton technology task is focused on issues related to systems integration. A brief description of ongoing technology activities is given.
Dramatic Expression in Opera, and Its Implications for Conversational Agents. Chapter 7
NASA Technical Reports Server (NTRS)
Johnson, W. Lewis
2007-01-01
This article has discussed principles, techniques, and methods of dramatic portrayal in opera, and their application to the development of embodied conversational agents. Investigations such as this complement studies of natural human behavior, and offer insights as to how to make such behavior understandable and interesting when adapted for use by embodied conversational agents. However, one should use caution in applying such lessons. The unique characteristics of computer-based media are still being identified and explored. In any case, one must always be careful about applying principles blindly to any artistic form. Such principles are post-hoc analysis of the intuitive skill of great artists; this was as true in Aristotle's day as it is today. We should not let structural principles stand in the way of injecting creativity into the design of ECAs. Opera at its best possesses an element of magic that is difficult to describe, much less analytically reconstruct. We can only hope to achieve a similar result with conversational agents.
ERIC Educational Resources Information Center
Sanger, Dixie; Ritzman, Mitzi; LaCost, Barbara; Stofer, Keri; Long, Amie; Grady, Marilyn
2005-01-01
This qualitative study explored the meanings of chat room conversations through observations of teenagers using the Internet. Adolescent girls were a focus because of their shaky sense of self. Participants in ten chat rooms included 534 individuals. Six themes, emerging from analyzing 2526 utterances [descriptive statements], included (a)…
Topic Negotiation in Peer Group Oral Assessment Situations: A Conversation Analytic Approach
ERIC Educational Resources Information Center
Gan, Zhengdong; Davison, Chris; Hamp-Lyons, Liz
2009-01-01
This study examines the production of topical talk in peer collaborative negotiation in an interactive assessment innovation context. The ability to stay on topic, to move from topic to topic and to introduce new topics appropriately is at the core of communicative competence. Applying conversation analysis (CA), we describe and analyze how one…
ERIC Educational Resources Information Center
Zenone, Anna
1981-01-01
Analyzes a type of conversational exchange where the participants focus on a given subject or theme contributing personal views to the discussion. Characterizes the relationship among the participants as a "cooperative conflict," examining the internal structure of speech acts and their illocutory functions, particularly the initiatory…
ERIC Educational Resources Information Center
Gabriel, Rachael
2017-01-01
Drawing upon discursive psychology as a theoretical and methodological framework, the author analyzes a set of five postobservation debrief conversations between novice teachers and their mentors. The author presents analysis and findings by highlighting how the interpretative repertoires of the rubric and protocol documents may be used to shape…
ERIC Educational Resources Information Center
van Dijk, Teun A.
In order to design a cognitive model of ethnic attitudes, an interdisciplinary project has analyzed strategies used in everyday conversation among majority members about minority groups, e.g., immigrant workers from Turkey and Morocco and people from Surinam. Data were collected through undirected interviews among people in an Amsterdam…
The role of lignin and lignin-like materials during wood hydrolysis
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zaher, F.A.
1981-01-01
The nature of the material precipitating from the acid prehydrolysates and hydrolysates of wood upon storage has been investigated. This material was analyzed for its sugar content, ultraviolet spectra, elemental composition, molecular weight distribution, and thermogravimetric behavior. All the results indicate that this material has the same properties as lignin. The results suggest also that this material is neither a resinification product from sugar decomposition nor extraneous materials of wood (resins, tannins, etc.). It is suggested, too, that the extraction of this material along with sugar during hydrolysis and prehydrolysis causes a considerable error in the results of wood analysismore » using standard methods based on weight loss. The actual percentages of lignin in the wood samples tested appear to vary from two to four times their values measured by standard methods. Consequently, the actual cellulose content of these materials may be far lower than has been reported. This has serious implications for schemes based on biomass conversion.« less
Analysis of adjusting effects of mounting force on frequency conversion of mounted nonlinear optics.
Su, Ruifeng; Liu, Haitao; Liang, Yingchun; Lu, Lihua
2014-01-10
Motivated by the need to increase the second harmonic generation (SHG) efficiency of nonlinear optics with large apertures, a novel mounting configuration with active adjusting function on the SHG efficiency is proposed and mechanically and optically studied. The adjusting effects of the mounting force on the distortion and stress are analyzed by the finite element methods (FEM), as well as the contribution of the distortion and stress to the change in phase mismatch, and the SHG efficiency are theoretically stated. Further on, the SHG efficiency is calculated as a function of the mounting force. The changing trends of the distortion, stress, and the SHG efficiency with the varying mounting force are obtained, and the optimal ones are figured out. Moreover, the mechanism of the occurrence of the optimal values is studied and the adjusting strategy is put forward. Numerical results show the robust adjustment of the mounting force, as well as the effectiveness of the mounting configuration, in increasing the SHG efficiency.
Howe, Gerald B; Loveless, Bonnie M; Norwood, David; Craw, Philip; Waag, David; England, Marilyn; Lowe, John R; Courtney, Bernard C; Pitt, M Louise; Kulesh, David A
2009-01-01
Real-time PCR was used to analyze archived blood from non-human primates (NHP) and fluid samples originating from a well-controlled Q fever vaccine efficacy trial. The PCR targets were the IS1111 element and the com1 gene of Coxiella burnetii. Data from that previous study were used to evaluate real-time PCR as an alternative to the use of sero-conversion by mouse bioassay for both quantification and early detection of C. burnetii bacteria. Real-time PCR and the mouse bioassay exhibited no statistical difference in quantifying the number of microorganisms delivered in the aerosol challenge dose. The presence of C. burnetii in peripheral blood of non-human primates was detected by real-time PCR as early after exposure as the mouse bioassay with results available within hours instead of weeks. This study demonstrates that real-time PCR has the ability to replace the mouse bioassay to measure dosage and monitor infection of C. burnetii in a non-human primate model.
Mohan, Vishnu; Hersh, William R
2013-01-01
There is a need for informatics educational programs to develop laboratory courses that facilitate hands-on access to an EHR, and allow students to learn and evaluate functionality and configuration options. This is particularly relevant given the diversity of backgrounds of informatics students. We implemented an EHR laboratory course that allowed students to explore an EHR in both inpatient and outpatient clinical environments. The course focused on specific elements of the EHR including order set development, customization, clinical decision support, ancillary services, and billing and coding functionality. Students were surveyed at the end of the course for their satisfaction with the learning experience. We detailed challenges as well as lessons learned after analyzing student evaluations of this course. Features that promote the successful offering of an online EHR course, include (1) using more than one EHR to allow students to compare functionalities, (2) ensuring appropriate course calibration, (3) countering issues specific to EHR usability, and (4) fostering a fertile environment for rich online conversations are discussed.
MusTRD can regulate postnatal fiber-specific expression.
Issa, Laura L; Palmer, Stephen J; Guven, Kim L; Santucci, Nicole; Hodgson, Vanessa R M; Popovic, Kata; Joya, Josephine E; Hardeman, Edna C
2006-05-01
Human MusTRD1alpha1 was isolated as a result of its ability to bind a critical element within the Troponin I slow upstream enhancer (TnIslow USE) and was predicted to be a regulator of slow fiber-specific genes. To test this hypothesis in vivo, we generated transgenic mice expressing hMusTRD1alpha1 in skeletal muscle. Adult transgenic mice show a complete loss of slow fibers and a concomitant replacement by fast IIA fibers, resulting in postural muscle weakness. However, developmental analysis demonstrates that transgene expression has no impact on embryonic patterning of slow fibers but causes a gradual postnatal slow to fast fiber conversion. This conversion was underpinned by a demonstrable repression of many slow fiber-specific genes, whereas fast fiber-specific gene expression was either unchanged or enhanced. These data are consistent with our initial predictions for hMusTRD1alpha1 and suggest that slow fiber genes contain a specific common regulatory element that can be targeted by MusTRD proteins.
A functional metagenomic approach for expanding the synthetic biology toolbox for biomass conversion
Sommer, Morten OA; Church, George M; Dantas, Gautam
2010-01-01
Sustainable biofuel alternatives to fossil fuel energy are hampered by recalcitrance and toxicity of biomass substrates to microbial biocatalysts. To address this issue, we present a culture-independent functional metagenomic platform for mining Nature's vast enzymatic reservoir and show its relevance to biomass conversion. We performed functional selections on 4.7 Gb of metagenomic fosmid libraries and show that genetic elements conferring tolerance toward seven important biomass inhibitors can be identified. We select two metagenomic fosmids that improve the growth of Escherichia coli by 5.7- and 6.9-fold in the presence of inhibitory concentrations of syringaldehyde and 2-furoic acid, respectively, and identify the individual genes responsible for these tolerance phenotypes. Finally, we combine the individual genes to create a three-gene construct that confers tolerance to mixtures of these important biomass inhibitors. This platform presents a route for expanding the repertoire of genetic elements available to synthetic biology and provides a starting point for efforts to engineer robust strains for biofuel generation. PMID:20393580
Investigation on energy conversion technology using biochemical reaction elements, 2
NASA Astrophysics Data System (ADS)
1994-03-01
For measures taken for resource/energy and environmental issues, a study is made on utilization of microbial biochemical reaction. As a reaction system using chemical energy, cited is production of petroleum substitution substances and food/feed by CO2 fixation using hydrogen energy and hydrogen bacteria. As to photo energy utilization, regarded as promising are CO2 fixation using photo energy and microalgae, and production of hydrogen and useful carbon compound using photosynthetic organisms. As living organism/electric energy interconversion, cited is the culture of chemoautotrophic bacteria which fix CO2 using electric energy. For enhancing its conversion efficiency, it is important to develop a technology of gene manipulation of the bacteria and a system to use functional biochemical elements adaptable to the electrode reaction. With regard to utilization of the microorganism metabolic function, the paper presents emission of soluble nitrogen in the hydrosphere into the atmosphere using denitrifying bacteria, removal of phosphorus, reduction in environmental pollution caused by heavy metal dilute solutions, and recovery as resources, etc.
Peracchi, Marta; Zorzi, Diego; Fiorio, Silvia; Fallico, Loredana; Palù, Giorgio
2012-01-01
Gamma interferon release assays were recently introduced in health care worker (HCWs) screenings for tuberculosis surveillance. In longitudinal surveys, conversions and reversions are seen, and yet whether these changes are unspecific or are an expression of new infections and microbial clearance remains unclear. In order to further elucidate these changes, we analyzed an outbreak of 15 transient conversions in 53 HCWs who operate in the same laboratory and handle specimens potentially containing Mycobacterium tuberculosis who underwent screening by the QuantiFERON-TB Gold In-Tube (QFT-GIT) test between 11 May and 30 June 2010: 15/46 (33%) negative HCWs showed a conversion and then reverted after 7 to 107 days. To validate these results, an evaluation of methodological procedures and test reliability, as well as an analysis of results obtained during the same period and processed by the same laboratory, was carried out. For the latter purpose, QFT-GIT results determined for 78 ward HCWs who underwent screening during the same period and were employed in departments with at least 3 infectious tuberculosis patients per year or had cared for an infectious patient without airborne precautions were analyzed with the following results: 6/63 (9%) HCWs with negative results in 3 different departments showed transient conversion (P = 0.002; odds ratio, 4.60; 95% confidence interval, 1.62 to 13.04). A retrospective survey of in-house biosafety practices led to determination of a single exposure factor within the laboratory. These data emphasize the validity of the hypothesis that a transient conversion demonstrates the presence of a real tubercular infection and could be an important indicator for occupational biosafety concerns. They also confirm that subjects with recent conversion should be retested before chest radiography and chemotherapy is offered. PMID:22518010
Zhao, Yi; Cao, Xiangyu; Gao, Jun; Liu, Xiao; Li, Sijia
2016-05-16
We demonstrate a simple reconfigurable metasurface with multiple functions. Anisotropic tiles are investigated and manufactured as fundamental elements. Then, the tiles are combined in a certain sequence to construct a metasurface. Each of the tiles can be adjusted independently which is like a jigsaw puzzle and the whole metasurface can achieve diverse functions by different layouts. For demonstration purposes, we realize polarization conversion, anomalous reflection and diffusion by a jigsaw puzzle metasurface with 6 × 6 pieces of anisotropic tile. Simulated and measured results prove that our method offers a simple and effective strategy for metasurface design.
Thermodynamics fundamentals of energy conversion
NASA Astrophysics Data System (ADS)
Dan, Nicolae
The work reported in the chapters 1-5 focuses on the fundamentals of heat transfer, fluid dynamics, thermodynamics and electrical phenomena related to the conversion of one form of energy to another. Chapter 6 is a re-examination of the fundamental heat transfer problem of how to connect a finite-size heat generating volume to a concentrated sink. Chapter 1 extends to electrical machines the combined thermodynamics and heat transfer optimization approach that has been developed for heat engines. The conversion efficiency at maximum power is 1/2. When, as in specific applications, the operating temperature of windings must not exceed a specified level, the power output is lower and efficiency higher. Chapter 2 addresses the fundamental problem of determining the optimal history (regime of operation) of a battery so that the work output is maximum. Chapters 3 and 4 report the energy conversion aspects of an expanding mixture of hot particles, steam and liquid water. At the elemental level, steam annuli develop around the spherical drops as time increases. At the mixture level, the density decreases while the pressure and velocity increases. Chapter 4 describes numerically, based on the finite element method, the time evolution of the expanding mixture of hot spherical particles, steam and water. The fluid particles are moved in time in a Lagrangian manner to simulate the change of the domain configuration. Chapter 5 describes the process of thermal interaction between the molten material and water. In the second part of the chapter the model accounts for the irreversibility due to the flow of the mixture through the cracks of the mixing vessel. The approach presented in this chapter is based on exergy analysis and represents a departure from the line of inquiry that was followed in chapters 3-4. Chapter 6 shows that the geometry of the heat flow path between a volume and one point can be optimized in two fundamentally different ways. In the "growth" method the structure is optimized starting from the smallest volume element of fixed size. In "design" method the overall volume is fixed, and the designer works "inward" by increasing the internal complexity of the paths for heat flow.
Conversion loss and noise of microwave and millimeter-wave mixers. I - Theory. II - Experiment
NASA Technical Reports Server (NTRS)
Held, D. N.; Kerr, A. R.
1978-01-01
The conversion loss and noise of microwave and millimeter-wave mixers are analyzed. Nonlinear capacitance, arbitrary embedding impedances, as well as shot, thermal and scattering noise arising in the diode, figure in the analysis. The anomalous mixer noise noted in millimeter-wave mixers by Kerr (1975) is shown to be explainable in terms of the correlation of down-converted components of the time-varying shot noise. A digital computer analysis of the conversion loss, noise, and output impedance of an 80-120-GHz mixer is also conducted.
Weight conversations in romantic relationships: What do they sound like and how do partners respond?
Berge, Jerica M; Pratt, Keeley; Miller, Laura
2016-09-01
The limited research examining weight conversations (i.e., conversations about weight, body shape, or size) in adult romantic relationships has shown associations between engaging in these conversations and disordered eating behaviors, overweight/obesity, and psychosocial problems in adults. Given the potential harmful consequences of these conversations, it is important to gather more rich qualitative data to understand how weight talk is experienced in romantic relationships and how romantic partners respond to these conversations. Adults (n = 118; mean age 35 years) from a cross-sectional study were interviewed in their homes. The majority of adults (90% female; mean age = 35 years) were from minority (64% African American) and low-income (<$25,000/year) households. Qualitative data were analyzed using inductive content analysis. Sixty-five percent of participants reported that weight conversations were occurring in their romantic relationships. Qualitative themes included the following: (a) Weight conversations were direct and focused on physical characteristics; (b) weight conversations included joking or sarcastic remarks; (c) weight conversations focused on "we" and being healthy; (d) weight conversations occurred after watching TV or movies, as a result of insecurities in oneself, as length of the relationship increased, or as partners aged; and (e) partners responded to weight conversations by feeling insecure or by engaging in reciprocal weight conversations with their romantic partner. Weight conversations were prevalent in romantic relationships, with some conversations experienced as negative and some positive. Qualitative themes from the current study should be confirmed in quantitative studies to inform future intervention research targeting weight conversations in romantic relationships. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Underpotential deposition-mediated layer-by-layer growth of thin films
Wang, Jia Xu; Adzic, Radoslav R.
2015-05-19
A method of depositing contiguous, conformal submonolayer-to-multilayer thin films with atomic-level control is described. The process involves the use of underpotential deposition of a first element to mediate the growth of a second material by overpotential deposition. Deposition occurs between a potential positive to the bulk deposition potential for the mediating element where a full monolayer of mediating element forms, and a potential which is less than, or only slightly greater than, the bulk deposition potential of the material to be deposited. By cycling the applied voltage between the bulk deposition potential for the mediating element and the material to be deposited, repeated desorption/adsorption of the mediating element during each potential cycle can be used to precisely control film growth on a layer-by-layer basis. This process is especially suitable for the formation of a catalytically active layer on core-shell particles for use in energy conversion devices such as fuel cells.
Lambert-Kerzner, Anne; Havranek, Edward P; Plomondon, Mary E; Albright, Karen; Moore, Ashley; Gryniewicz, Kelsey; Magid, David; Ho, P Michael
2010-11-01
Few studies have investigated the effectiveness of multifaceted interventions from the study participants' perspective. We conducted qualitative interviews to understand patients' experiences with a multifaceted blood pressure (BP) control intervention involving interactive voice response technology, home BP monitoring, and pharmacist-led BP management. In the randomized study, the intervention resulted in clinically significant decreases in BP. We used insights generated from in-depth interviews from all study participants randomly assigned to the multifaceted intervention or usual care (n=146) to create a model explaining the observed improvements in health behavior and clinical outcomes. The data were analyzed using qualitative content analysis methods and consultative and reflexive team analysis. Six explanatory factors emerged from the patients' interviews: (1) improved relationships with medical personnel; (2) increased knowledge of hypertension; (3) increased participation in their health care and personal empowerment; (4) greater understanding of the impact of health behavior on BP; (5) high satisfaction with technology used in the intervention; and, for some patients, (6) increased health care utilization. Eighty-six percent of the intervention patients and 62% of the usual care patients stated that study participation had a positive effect on them. Of those expressing a positive effect, 68% (intervention) and 55% (usual care) reached their systolic BP goal. Establishing bidirectional conversations between patients and providers is a key element of successful hypertension management. Home BP monitoring coupled with interactive voice response technology reporting facilitates such conversations.
Biased Gene Conversion and GC-Content Evolution in the Coding Sequences of Reptiles and Vertebrates
Figuet, Emeric; Ballenghien, Marion; Romiguier, Jonathan; Galtier, Nicolas
2015-01-01
Mammalian and avian genomes are characterized by a substantial spatial heterogeneity of GC-content, which is often interpreted as reflecting the effect of local GC-biased gene conversion (gBGC), a meiotic repair bias that favors G and C over A and T alleles in high-recombining genomic regions. Surprisingly, the first fully sequenced nonavian sauropsid (i.e., reptile), the green anole Anolis carolinensis, revealed a highly homogeneous genomic GC-content landscape, suggesting the possibility that gBGC might not be at work in this lineage. Here, we analyze GC-content evolution at third-codon positions (GC3) in 44 vertebrates species, including eight newly sequenced transcriptomes, with a specific focus on nonavian sauropsids. We report that reptiles, including the green anole, have a genome-wide distribution of GC3 similar to that of mammals and birds, and we infer a strong GC3-heterogeneity to be already present in the tetrapod ancestor. We further show that the dynamic of coding sequence GC-content is largely governed by karyotypic features in vertebrates, notably in the green anole, in agreement with the gBGC hypothesis. The discrepancy between third-codon positions and noncoding DNA regarding GC-content dynamics in the green anole could not be explained by the activity of transposable elements or selection on codon usage. This analysis highlights the unique value of third-codon positions as an insertion/deletion-free marker of nucleotide substitution biases that ultimately affect the evolution of proteins. PMID:25527834
NASA Astrophysics Data System (ADS)
Ryzhii, V.; Shur, M. S.; Ryzhii, M.; Karasik, V. E.; Otsuji, T.
2018-01-01
We developed a device model for pixelless converters of far/mid-infrared radiation (FIR/MIR) images into near-infrared/visible (NIR/VIR) images. These converters use polycrystalline graphene layers (PGLs) immersed in the van der Waals materials integrated with a light emitting diode (LED). The PGL serves as an element of the PGL infrared photodetector (PGLIP) sensitive to the incoming FIR/MIR due to the interband absorption. The spatially non-uniform photocurrent generated in the PGLIP repeats (mimics) the non-uniform distribution (image) created by the incident FIR/MIR. The injection of the nonuniform photocurrent into the LED active layer results in the nonuniform NIR/VIR image reproducing the FIR/MIR image. The PGL and the entire layer structure are not deliberately partitioned into pixels. We analyze the characteristics of such pixelless PGLIP-LED up-converters and show that their image contrast transfer function and the up-conversion efficiency depend on the PGL lateral resistivity. The up-converter exhibits high photoconductive gain and conversion efficiency when the lateral resistivity is sufficiently high. Several teams have successfully demonstrated the large area PGLs with the resistivities varying in a wide range. Such layers can be used in the pixelless PGLIP-LED image up-converters. The PGLIP-LED image up-converters can substantially surpass the image up-converters based on the quantum-well infrared photodetector integrated with the LED. These advantages are due to the use of the interband FIR/NIR absorption and a high photoconductive gain in the GLIPs.
The NASA CSTI high capacity power project
NASA Technical Reports Server (NTRS)
Winter, J.; Dudenhoefer, J.; Juhasz, A.; Schwarze, G.; Patterson, R.; Ferguson, D.; Titran, R.; Schmitz, P.; Vandersande, J.
1992-01-01
The SP-100 Space Nuclear Power Program was established in 1983 by DOD, DOE, and NASA as a joint program to develop technology for military and civil applications. Starting in 1986, NASA has funded a technology program to maintain the momentum of promising aerospace technology advancement started during Phase 1 of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for a wide range of future space applications. The elements of the Civilian Space Technology Initiative (CSTI) High Capacity Power Project include Systems Analysis, Stirling Power Conversion, Thermoelectric Power Conversion, Thermal Management, Power Management, Systems Diagnostics, Environmental Interactions, and Material/Structural Development. Technology advancement in all elements is required to provide the growth capability, high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall project will develop and demonstrate the technology base required to provide a wide range of modular power systems compatible with the SP-100 reactor which facilitates operation during lunar and planetary day/night cycles as well as allowing spacecraft operation at any attitude or distance from the sun. Significant accomplishments in all of the project elements will be presented, along with revised goals and project timelines recently developed.
The NASA CSTI high capacity power project
NASA Astrophysics Data System (ADS)
Winter, J.; Dudenhoefer, J.; Juhasz, A.; Schwarze, G.; Patterson, R.; Ferguson, D.; Titran, R.; Schmitz, P.; Vandersande, J.
1992-08-01
The SP-100 Space Nuclear Power Program was established in 1983 by DOD, DOE, and NASA as a joint program to develop technology for military and civil applications. Starting in 1986, NASA has funded a technology program to maintain the momentum of promising aerospace technology advancement started during Phase 1 of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for a wide range of future space applications. The elements of the Civilian Space Technology Initiative (CSTI) High Capacity Power Project include Systems Analysis, Stirling Power Conversion, Thermoelectric Power Conversion, Thermal Management, Power Management, Systems Diagnostics, Environmental Interactions, and Material/Structural Development. Technology advancement in all elements is required to provide the growth capability, high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall project will develop and demonstrate the technology base required to provide a wide range of modular power systems compatible with the SP-100 reactor which facilitates operation during lunar and planetary day/night cycles as well as allowing spacecraft operation at any attitude or distance from the sun. Significant accomplishments in all of the project elements will be presented, along with revised goals and project timelines recently developed.
Systems and methods for compensating for electrical converter nonlinearities
Perisic, Milun; Ransom, Ray M.; Kajouke, Lateef A.
2013-06-18
Systems and methods are provided for delivering energy from an input interface to an output interface. An electrical system includes an input interface, an output interface, an energy conversion module coupled between the input interface and the output interface, and a control module. The control module determines a duty cycle control value for operating the energy conversion module to produce a desired voltage at the output interface. The control module determines an input power error at the input interface and adjusts the duty cycle control value in a manner that is influenced by the input power error, resulting in a compensated duty cycle control value. The control module operates switching elements of the energy conversion module to deliver energy to the output interface with a duty cycle that is influenced by the compensated duty cycle control value.
Critical technology limits to silicon material and sheet production
NASA Technical Reports Server (NTRS)
Leipold, M. H.
1982-01-01
Earlier studies have indicated that expenditures related to the preparation of high-purity silicon and its conversion to silicon sheet represent from 40 to 52 percent of the cost of the entire panel. The present investigation is concerned with the elements which were selected for study in connection with the Flat-Plate Solar Array (FSA) Project. The first of two technologies which are being developed within the FSA Project involves the conversion of metallurgical-grade silicon through a silane purification process to silicon particles. The second is concerned with the conversion of trichlorosilane to dichlorosilane, and the subsequent production of silicon using modified rod reactors of the Siemens type. With respect to silicon sheet preparation, efforts have been focused both on the preparation of ingots, followed by wafering, and the direct crystallization of molten silicon into a ribbon or film.
Rectification of Lamb wave propagation in thin plates with piezo-dielectric periodic structures
NASA Astrophysics Data System (ADS)
Iwasaki, Yuhei; Tsuruta, Kenji; Ishikawa, Atsushi
2016-07-01
Based on a heterostructured plate consisting of piezoelectric-ceramic/epoxy-resin composites with different periodicities, we design a novel acoustic diode for the symmetrical/asymmetrical (S/A) mode of Lamb wave at audible ranges. The acoustic diode is constructed with two parts, i.e., the mode conversion part and the mode selection part, and the mode conversion mechanism at the interface is applied to the mode hybridization from S to S+A and for the mode conversion from A to S. The phonon band structures for each part are calculated and optimized so that the mode selection is realized for a specific mode at the junction. Finite-element simulations prove that the proposed acoustic diode achieves efficient rectification at audio frequency ranges for both S and A mode incidences of the Lamb wave.
Conversion of Nuclear Waste to Molten Glass: Cold-Cap Reactions in Crucible Tests
Xu, Kai; Hrma, Pavel; Rice, Jarrett A.; ...
2016-05-23
The feed-to-glass conversion, which comprises complex chemical reactions and phase transitions, occurs in the cold cap during nuclear waste vitrification. Here, to investigate the conversion process, we analyzed heat-treated samples of a simulated high-level waste feed using X-ray diffraction, electron probe microanalysis, leaching tests, and residual anion analysis. Feed dehydration, gas evolution, and borate phase formation occurred at temperatures below 700°C before the emerging glass-forming melt was completely connected. Above 700°C, intermediate aluminosilicate phases and quartz particles gradually dissolved in the continuous borosilicate melt, which expanded with transient foam. Finally, knowledge of the chemistry and physics of feed-to-glass conversion willmore » help us control the conversion path by changing the melter feed makeup to maximize the glass production rate.« less
Power Tools for Talking: Custom Protocols Enrich Coaching Conversations
ERIC Educational Resources Information Center
Pomerantz, Francesca; Ippolito, Jacy
2015-01-01
Discussion-based protocols--an "agreed upon set of discussion or observation rules that guide coach/teacher/student work, discussion, and interactions" (Ippolito & Lieberman, 2012, p. 79)--can help focus and structure productive professional learning discussions. However, while protocols are slowly growing into essential elements of…
A Functional Syntax of German.
ERIC Educational Resources Information Center
Fichtner, Edward G.
Students in intermediate language courses, especially conversational courses, can benefit from a simple set of instructions for combining words and phrases into sentences. A description of the basic concepts determining word order in German--the fundamental sequence of clause elements, the "infrastructure," and the movement rules by which the…
Acronyms, initialisms, and abbreviations: Fourth Revision
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tolman, B.J.
1994-04-01
This document lists acronyms used in technical writing. The immense list is supplemented by an appendix containing chemical elements, classified information access, common abbreviations used for functions, conversion factors for selected SI units, a flowcharting template, greek alphabet, metrix terminology, proofreader`s marks, signs and symbols, and state abbreviations.
Doing Business with Entrepreneurial America: Protecting School District Interests.
ERIC Educational Resources Information Center
McCord, Robert S.; Mattocks, T. C.; Kops, Gerald
This paper attempts to identify benchmark considerations when entertaining the question of private management of public school facilities. Management possibilities include contracting for services and charter conversion. The paper also highlights elements of contract law pertinent to formal agreements made between school districts and private…
Groysberg, Boris; Slind, Michael
2012-06-01
Globalization and new technologies have sharply reduced the efficacy of command-and-control management and its accompanying forms of corporate communication. In the course of a recent research project, the authors concluded that by talking with employees, rather than simply issuing orders, leaders can promote operational flexibility, employee engagement, and tight strategic alignment. Groysberg and Slind have identified four elements of organizational conversation that reflect the essential attributes of interpersonal conversation: intimacy, interactivity, inclusion, and intentionality. Intimacy shifts the focus from a top-down distribution of information to a bottom-up exchange of ideas. Organizational conversation is less corporate in tone and more casual. And it's less about issuing and taking orders than about asking and answering questions. Interactivity entails shunning the simplicity of monologue and embracing the unpredictable vitality of dialogue. Traditional one-way media-print and broadcast, in particular-give way to social media buttressed by social thinking. Inclusion turns employees into full-fledged conversation partners, entitling them to provide their own ideas, often on company channels. They can create content and act as brand ambassadors, thought leaders, and storytellers. Intentionality enables leaders and employees to derive strategically relevant action from the push and pull of discussion and debate.
Conversion of zirconacyclopentadienes into metalloles: Fagan-Nugent reaction and beyond.
Yan, Xiaoyu; Xi, Chanjuan
2015-04-21
Metalloles are derivatives of cyclopentadiene in which the methylene unit is replaced by a heteroatom, such as S, Se, Te, N, P, As, Sb, Bi, Si, Ge, Sn, B, Al, Ga, and so on. Many metallole derivatives have been widely used as photovoltaic cells, organic light emitting diodes (OLEDs), chemical sensors, electrochromic devices, microelectronic actuators, and organic field effect transistors (OFETs). In the meantime, many of them showed promising biological actives. Due to the similarity to cyclopentadiene, the anionic forms of metalloles were also widely explored in coordination chemistry. As a result, development of a general method for the formation of metalloles from available starting materials is highly desired. In this Account, we outline formation of various p-block element metalloles from zirconacyclopentadienes. The zirconacyclopentadienes can be easily prepared from two molecules of alkynes and a low-valent zirconocene species "Cp2Zr(II)" (Cp = cyclopentadienyl). Fagan and Nugent first reported the formation of main group metalloles from zirconacyclopentadiene, which provided a versatile approach for the construction of metalloles, especially for the formation of metalloles in heavier p-block elements. To further expand the substrate scope, a number of stepwise conversions were developed, which involve 1,4-dimetallo- or dihalo-1,3-butadiene as intermediates from zirconacyclopentadienes. Here, four processes are classified based on direct and indirect conversion of zirconacyclopentadienes into metalloles. Direct reaction of zirconacyclopentadienes with element halides afforded heterocycles of main group elements, which provided a versatile method for the synthesis of metalloles. Nonetheless, the reaction scope was restricted to heavier p-block elements such as S, Se, P, As, Sb, Bi, Ge, Sn, Ga, and In. And these reactions usually suffered low yields and long reaction time. Transmetalation of zirconacyclopentadiene with copper chloride greatly enriched the zirconacyclopentadiene chemistry. The synthesis of stannoles and pyrroles from zirconacyclopentadienes has been developed in the presence of CuCl. The direct reaction of the zirconacyclopentadienes with SiCl4 or R2SiCl2 does not give the desired silacyclopendadiene derivatives, even in the presence of CuCl. It can be circumvented by using dilithiated dienes from diiododienes, which are easily prepared by the iodination of zirconacyclopentadienes using CuCl as an additive. Finally, an umpolung strategy, reaction of electrophilic 1,4-diiodo-1,3-butadiene with nucleophilic amine or sulfide reagents, was successfully used in the formation of pyrroles and thiophenes.
Sun, Bo; Xue, Sheng-Ling; Zhang, Fen; Luo, Zhao-Peng; Wu, Ming-Zhu; Chen, Qing; Tang, Hao-Ru; Lin, Fu-Cheng; Yang, Jun
2015-11-17
Nornicotine production in Nicotiana tabacum is undesirable because it is the precursor of the carcinogen N'-nitrosonornicotine. In some individual burley tobacco plants, a large proportion of the nicotine can be converted to nornicotine, and this process of nicotine conversion is mediated primarily by enzymatic N-demethylation of nicotine which is controlled mainly by CYP82E4. Here we report a novel strategy based on quantitative real-time polymerase chain reaction (qPCR) method, which analyzed the ratio of nicotine conversion through examining the transcript level of CYP82E4 in burley leaves and do not need ethylene induction before detected. The assay was linear in a range from 1 × 10¹ to 1 × 10⁵ copies/mL of serially diluted standards, and also showed high specificity and reproducibility (93%-99%). To assess its applicability, 55 plants of burley cultivar Ky8959 at leaf maturing stage were analyzed, and the results were in accordance with those from gas chromatograph-mass spectrometry (GC-MS) method. Moreover, a linear correlation existed between conversion level and CYP82E4 transcript abundance. Taken together, the quantitative real-time PCR assay is standardized, rapid and reproducible for estimation of nicotine conversion level in vivo, which is expected to shed new light on monitoring of burley tobacco converter.
Sun, Caili; Liu, Guobin; Xue, Sha
2016-01-01
Analyzing the dynamics of soil particle-size distributions (PSDs), soil nutrients, and erodibility are very important for understanding the changes of soil structure and quality after long-term land-use conversion. We applied multifractal Rényi spectra (Dq) and singularity spectra (f(α)) to characterize PSDs 35 years after conversions from cropland to shrubland with Caragana microphylla (shrubland I), shrubland with Hippophae rhamnoides (shrubland II), forested land, and grassland on the Loess Plateau of China. Multifractal parameters (capacity dimension (D0), entropy dimension (D1), D1/D0, correlation dimension (D2), and Hölder exponent of order zero (α0)) were used to analyze the changes of PSDs. Dq and f(α) characterized the PSDs well and sensitively represented the changes in PSDs after conversion. All types of land-use conversion significantly improved the properties of the topsoil (0–10 cm), but the effect of shrubland I and even forested land decreased with depth. All types of land-use conversion significantly increased D1 and D2 in the topsoil, and D1 and D2 in the 10–50 cm layers of shrubland II, forested land, and grassland and D1 in the 50–100 cm layers of shrubland II were significantly higher relative to the control. Both D1 and D2 were positively correlated with the contents of soil nutrients and fine particles and were negatively correlated with soil erosion, indicating that D1 and D2 were potential indices for quantifying changes in soil properties and erosion. In conclusion, all types of land-use conversion significantly improved the conditions of the topsoil, but conversion from cropland to shrubland II, forested land, and grassland, especially shrubland II and grassland, were more effective for improving soil conditions in deeper layers. PMID:27527201
Rapid Analysis of Ash Composition Using Laser-Induced Breakdown Spectroscopy (LIBS)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tyler L. Westover
2013-01-01
Inorganic compounds are known to be problematic in the thermochemical conversion of biomass to syngas and ultimately hydrocarbon fuels. The elements Si, K, Ca, Na, S, P, Cl, Mg, Fe, and Al are particularly problematic and are known to influence reaction pathways, contribute to fouling and corrosion, poison catalysts, and impact waste streams. Substantial quantities of inorganic species can be entrained in the bark of trees during harvest operations. Herbaceous feedstocks often have even greater quantities of inorganic constituents, which can account for as much as one-fifth of the total dry matter. Current methodologies to measure the concentrations of thesemore » elements, such as inductively coupled plasma-optical emission spectrometry/mass spectrometry (ICP-OES/MS) are expensive in time and reagents. This study demonstrates that a new methodology employing laser-induced breakdown spectroscopy (LIBS) can rapidly and accurately analyze the inorganic constituents in a wide range of biomass materials, including both woody and herbaceous examples. This technique requires little or no sample preparation, does not consume any reagents, and the analytical data is available immediately. In addition to comparing LIBS data with the results from ICP-OES methods, this work also includes discussions of sample preparation techniques, calibration curves for interpreting LIBS spectra, minimum detection limits, and the use of internal standards and standard reference materials.« less
ERIC Educational Resources Information Center
Bauer, Patricia J.; Burch, Melissa M.; Van Abbema, Dana L.; Ackil, Jennifer K.
2007-01-01
Mother-child dyads who experienced a devastating tornado talked about the storm and about two affectively more positive or neutral events at each of two time points: 4 months and 10 months after the storm. The conversations were analyzed to determine whether mothers and/or children's contributions differed as a function of event type and whether…
David S. Leigh; Theodore L. Gragson; Michael R. Coughlan
2015-01-01
This paper presents a place-based examination of the timing and long-term pedogenic effects of human-induced forest to pasture conversion in the French western Pyrenees Mountains, Basque commune of Larrau. We analyzed colluvial stratigraphic sections to derive the chronology of landscape change using radiocarbon dating, charcoal concentrations, magnetic...
ERIC Educational Resources Information Center
Fatigante, Marilena; Fasulo, Alessandra; Pontecorvo, Clotilde
1998-01-01
A qualitative study analyzed the distribution of participation by young children (ages 3-5) in family dinnertime conversation, focusing on "backstage talk," sequences adjacent to those in which the child is involved and within his auditory range, so that the child-projected participation-role alternates between that of addressee and overhearer.…
Thin film solar cells grown by organic vapor phase deposition
NASA Astrophysics Data System (ADS)
Yang, Fan
Organic solar cells have the potential to provide low-cost photovoltaic devices as a clean and renewable energy resource. In this thesis, we focus on understanding the energy conversion process in organic solar cells, and improving the power conversion efficiencies via controlled growth of organic nanostructures. First, we explain the unique optical and electrical properties of organic materials used for photovoltaics, and the excitonic energy conversion process in donor-acceptor heterojunction solar cells that place several limiting factors of their power conversion efficiency. Then, strategies for improving exciton diffusion and carrier collection are analyzed using dynamical Monte Carlo models for several nanostructure morphologies. Organic vapor phase deposition is used for controlling materials crystallization and film morphology. We improve the exciton diffusion efficiency while maintaining good carrier conduction in a bulk heterojunction solar cell. Further efficiency improvement is obtained in a novel nanocrystalline network structure with a thick absorbing layer, leading to the demonstration of an organic solar cell with 4.6% efficiency. In addition, solar cells using simultaneously active heterojunctions with broad spectral response are presented. We also analyze the efficiency limits of single and multiple junction organic solar cells, and discuss the challenges facing their practical implementations.
Transition Core Properties during Conversion of the NBSR from HEU to LEU Fuel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hanson, A. L.; Diamond, D.
2013-10-31
The transition of the NBSR from HEU to LEU fuel is challenging due to reactivity constraints and the need to maintain an uninterrupted science program, the mission of the NBSR. The transition cannot occur with a full change of HEU to LEU fuel elements since the excess reactivity would be large enough that the NBSR would violate the technical specification for shutdown margin. Manufacturing LEU fuel elements to represent irradiated fuel elements would be cost prohibitive since 26 one-of-a-kind fuel elements would need to be manufactured. For this report a gradual transition from the present HEU fuel to the proposedmore » LEU fuel was studied. The gradual change approach would follow the present fuel management scheme and replace four HEU fuel elements with four LEU fuel elements each cycle. This manuscript reports the results of a series of calculations to predict the neutronic characteristics and how the neutronics will change during the transition from HEU to LEU in the NBSR.« less
Scattering apodizer for laser beams
Summers, Mark A.; Hagen, Wilhelm F.; Boyd, Robert D.
1985-01-01
A method is disclosed for apodizing a laser beam to smooth out the production of diffraction peaks due to optical discontinuities in the path of the laser beam, such method comprising introduction of a pattern of scattering elements for reducing the peak intensity in the region of such optical discontinuities, such pattern having smoothly tapering boundaries in which the distribution density of the scattering elements is tapered gradually to produce small gradients in the distribution density, such pattern of scattering elements being effective to reduce and smooth out the diffraction effects which would otherwise be produced. The apodizer pattern may be produced by selectively blasting a surface of a transparent member with fine abrasive particles to produce a multitude of minute pits. In one embodiment, a scattering apodizer pattern is employed to overcome diffraction patterns in a multiple element crystal array for harmonic conversion of a laser beam. The interstices and the supporting grid between the crystal elements are obscured by the gradually tapered apodizer pattern of scattering elements.
Scattering apodizer for laser beams
Summers, M.A.; Hagen, W.F.; Boyd, R.D.
1984-01-01
A method is disclosed for apodizing a laser beam to smooth out the production of diffraction peaks due to optical discontinuities in the path of the laser beam, such method comprising introduction of a pattern of scattering elements for reducing the peak intensity in the region of such optical discontinuities, such pattern having smoothly tapering boundaries in which the distribution density of the scattering elements is tapered gradually to produce small gradients in the distribution density, such pattern of scattering elements being effective to reduce and smooth out the diffraction effects which would otherwise be produced. The apodizer pattern may be produced by selectively blasting a surface of a transparent member with fine abrasive particles to produce a multitude of minute pits. In one embodiment, a scattering apodizer pattern is employed to overcome diffraction patterns in a multiple element crystal array for harmonic conversion of a laser beam. The interstices and the supporting grid between the crystal elements are obscured by the gradually tapered apodizer pattern of scattering elements.
Lin, Qingyu; Wei, Zhimei; Guo, Hongli; Wang, Shuai; Guo, Guangmeng; Zhang, Zhi; Duan, Yixiang
2017-06-10
A highly concentrated, ring-shaped phase conversion (RSPC) method was developed for liquid sample analysis using the laser-induced breakdown spectroscopy (LIBS) technique. In this work, test samples were prepared by mixing the metal particles with polyvinyl alcohol (PVA) supporter in liquid phase. With heat, the PVA solution solidified inside a modified glass petri dish, forming a metal-enriched polymer ring film. Distinguished from other traditional liquid-to-solid conversing methods, the proposed new method takes advantage of enhanced homogeneity for the target elements inside the ring film. The modified glass petri dish was used to control the ring-shaped concentration. Due to the specially designed circular groove at the bottom of this dish, where the PVA solution and liquid sample mixture accumulated, the target elements were concentrated in this small ring, which is beneficial for enhancing and stabilizing the plasma signals compared to the direct liquid sample analysis using LIBS. The limits of detection for Ag, Cu, Cr, and Ba obtained with the RSPC-LIBS technology were 0.098 μg·mL -1 , 0.18 μg·mL -1 , 0.83 μg·mL -1 , and 0.046 μg·mL -1 , respectively, which provided greater improvement than the direct bulk liquid analysis using LIBS.
NASA Astrophysics Data System (ADS)
Kanematsu, Nobuyuki; Inaniwa, Taku; Nakao, Minoru
2016-07-01
In the conventional procedure for accurate Monte Carlo simulation of radiotherapy, a CT number given to each pixel of a patient image is directly converted to mass density and elemental composition using their respective functions that have been calibrated specifically for the relevant x-ray CT system. We propose an alternative approach that is a conversion in two steps: the first from CT number to density and the second from density to composition. Based on the latest compilation of standard tissues for reference adult male and female phantoms, we sorted the standard tissues into groups by mass density and defined the representative tissues by averaging the material properties per group. With these representative tissues, we formulated polyline relations between mass density and each of the following; electron density, stopping-power ratio and elemental densities. We also revised a procedure of stoichiometric calibration for CT-number conversion and demonstrated the two-step conversion method for a theoretically emulated CT system with hypothetical 80 keV photons. For the standard tissues, high correlation was generally observed between mass density and the other densities excluding those of C and O for the light spongiosa tissues between 1.0 g cm-3 and 1.1 g cm-3 occupying 1% of the human body mass. The polylines fitted to the dominant tissues were generally consistent with similar formulations in the literature. The two-step conversion procedure was demonstrated to be practical and will potentially facilitate Monte Carlo simulation for treatment planning and for retrospective analysis of treatment plans with little impact on the management of planning CT systems.
NASA Technical Reports Server (NTRS)
Lee, H. P.
1977-01-01
The NASTRAN Thermal Analyzer Manual describes the fundamental and theoretical treatment of the finite element method, with emphasis on the derivations of the constituent matrices of different elements and solution algorithms. Necessary information and data relating to the practical applications of engineering modeling are included.
NASA Astrophysics Data System (ADS)
Jain, Syadwad
In this study, the localized corrosion and conversion coating on cast alloys 356 (Al-7.0Si-0.3Mg) and 380 (Al-8.5Si-3.5Cu-1.6Fe) were characterized. The intermetallic phases presence in the permanent mold cast alloy 356 are primary-Si, Al5FeSi, Al8Si6Mg3Fe and Mg2Si. The die cast alloy 380 is rich in Cu and Fe elements. These alloying elements result in formation of the intermetallic phases Al 5FeSi, Al2Cu and Al(FeCuCr) along with primary-Si. The Cu- and Fe-rich IMPS are cathodic with respect to the matrix phase and strongly govern the corrosion behavior of the two cast alloys in an aggressive environment due to formation of local electrochemical cell in their vicinity. Results have shown that corrosion behavior of permanent mould cast alloy 356 is significantly better than the die cast aluminum alloy 380, primarily due to high content of Cu- and Fe-rich phases such as Al2Cu and Al 5FeSi in the latter. The IMPS also alter the protection mechanism of the cast alloys in the presence of inhibitors in an environment. The presence of chromate in the solution results in reduced cathodic activity on all the phases. Chromate provides some anodic inhibition by increasing pitting potentials and altering corrosion potentials for the phases. Results have shown that performance of CCC was much better on 356 than on 380, primarily due to inhomogeneous and incomplete coating deposition on Cu- and Fe- phases present in alloy 380. XPS and Raman were used to characterize coating deposition on intermetallics. Results show evidence of cyanide complex formation on the intermetallic phases. The presence of this complex is speculated to locally suppress CCC formation. Formation and breakdown of cerium conversion coatings on 356 and 380 was also analyzed. Results showed that deposition of cerium hydroxide started with heavy precipitation on intermetallic particles with the coatings growing outwards onto the matrix. Electrochemical analysis of synthesized intermetallics compounds in the presence of soluble cerium cations showed that of anodic and cathodic activity was not as strongly inhibited as was observed for chromate ions. Overall cerium conversion coating showed good performance on Al-Si (356) ally, but poor performance on Fe- and Cu-rich alloy (380).
Stepping into Science Fiction: Understanding the Genre
ERIC Educational Resources Information Center
Barone, Diane; Barone, Rebecca
2014-01-01
This manuscript focuses on fifth graders' understanding of science fiction. It is argued that it is necessary for students to understand both reading strategies and the key elements of a genre for comprehension. Students read "The Giver" within literature circles and conversation and written responses about the book were used for…
A COMPUTATIONAL AND EXPERIMENTAL STUDY OF MERCURY SPECIATION AS FACILITATED BY THE DEACON PROCESS
The paper gives results of a computational and experimental study of mercury (Hg) speciation as facilitated by the Deacon process. Fly ashes that contain trace cupric or ferric oxide are effective catalysts for elemental mercury (Hg) conversion to mercuric chloride in the presenc...
40 CFR 52.1162 - Regulation for bicycle use.
Code of Federal Regulations, 2010 CFR
2010-07-01
... painted lanes, pavement coloring or other appropriate markings. A peak hour bike lane means a bike lane... following elements: (1) The physical design for bikeways, intersections involving bikeways, and means of... conversion from auto use; (11) The special problems related to the design and incorporation in the bikeway...
40 CFR 52.1162 - Regulation for bicycle use.
Code of Federal Regulations, 2013 CFR
2013-07-01
... painted lanes, pavement coloring or other appropriate markings. A peak hour bike lane means a bike lane... following elements: (1) The physical design for bikeways, intersections involving bikeways, and means of... conversion from auto use; (11) The special problems related to the design and incorporation in the bikeway...
40 CFR 52.1162 - Regulation for bicycle use.
Code of Federal Regulations, 2012 CFR
2012-07-01
... painted lanes, pavement coloring or other appropriate markings. A peak hour bike lane means a bike lane... following elements: (1) The physical design for bikeways, intersections involving bikeways, and means of... conversion from auto use; (11) The special problems related to the design and incorporation in the bikeway...
40 CFR 52.1162 - Regulation for bicycle use.
Code of Federal Regulations, 2011 CFR
2011-07-01
... painted lanes, pavement coloring or other appropriate markings. A peak hour bike lane means a bike lane... following elements: (1) The physical design for bikeways, intersections involving bikeways, and means of... conversion from auto use; (11) The special problems related to the design and incorporation in the bikeway...
40 CFR 52.1162 - Regulation for bicycle use.
Code of Federal Regulations, 2014 CFR
2014-07-01
... painted lanes, pavement coloring or other appropriate markings. A peak hour bike lane means a bike lane... following elements: (1) The physical design for bikeways, intersections involving bikeways, and means of... conversion from auto use; (11) The special problems related to the design and incorporation in the bikeway...
Optimizing Student Learning: Examining the Use of Presentation Slides
ERIC Educational Resources Information Center
Strauss, Judy; Corrigan, Hope; Hofacker, Charles F.
2011-01-01
Sensory overload and split attention result in reduced learning when instructors read slides with bullet points and complex graphs during a lecture. Conversely, slides containing relevant visual elements, when accompanied by instructor narration, use both the visual and verbal channels of a student's working memory, thus improving the chances of…
Non-linear optical properties of arylfuranylpropenones
NASA Astrophysics Data System (ADS)
Holla, B. Shivarama; Veerendra, B.; Indira, J.
2003-05-01
A series of arylfuranylpropenones 3a-i were synthesized by the reaction of 5-(2-nitro-4-methoxyphenyl)-2-furfural 1 with various acetophenones 2 by Claisen-Schmidt condensation. All the newly synthesized chalcones were characterized by elemental analysis and spectral studies. Most of them showed SHG conversion efficiency in powder form.
Transaction Circles with Digital Texts as a Foundation for Democratic Practices
ERIC Educational Resources Information Center
Brown, Sally
2015-01-01
Transaction circles weave together elements of guided reading and literature circles in an open conversational structure that supports students as agentive learners. Discourse within these circles utilizing digital informational texts assist in the development of democratic practices even in a time when federal mandates limit curricula and…
Le Francais Courant, Part VI: Contemporary French.
ERIC Educational Resources Information Center
Dade County Public Schools, Miami, FL.
This course, developed largely within the framework of units 13, 14, and 15 of the second edition of "A-LM French, Level 2," emphasizes development of basic audiolingual skills. Conversational topics permit the student to review his summer vacation. Principal elements of structure are expressions of quantity, pronouns--including those…
Prosody and Formulaic Language in Treatment-Resistant Depression: Effects of Deep Brain Stimulation
ERIC Educational Resources Information Center
Bridges, Kelly A.
2014-01-01
Communication, specifically the elements crucial for normal social interaction, can be significantly affected in psychiatric illness, especially depression. Of specific importance are prosody (an aspect of speech that carries emotional valence) and formulaic language (non-novel linguistic segments that are prevalent in naturalistic conversation).…
Conversion of Nuclear Waste to Molten Glass: Cold-Cap Reactions in Crucible Tests
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xu, Kai; Hrma, Pavel; Rice, Jarrett A.
2016-05-23
The feed-to-glass conversion, which comprises complex chemical reactions and phase transitions, occurs in the cold-cap zone during nuclear waste vitrification. Knowledge of the chemistry and physics of feed-to-glass conversion will help us control the conversion path by changing the melter feed makeup to maximize the glass production rate. To investigate the conversion process, we analyzed heat-treated samples of a simulated high-level waste feed using X-ray diffraction, electron probe microanalysis – wavelength dispersive X-ray spectroscopy, leaching tests, and residual anion analysis. Feed dehydration, gas evolution, and borate phase formation occurred at temperatures below 700 °C before the emerging glass-forming melt wasmore » completely connected. Above 800 °C, intermediate aluminosilicate phases and quartz particles were gradually dissolving in the continuous borosilicate melt, which expanded into transient foam. Knowledge of the chemistry and physics of feed-to-glass conversion will help us control the conversion path by changing the melter feed makeup to maximize the glass production rate.« less
Tavano, Alessandro; Pesarin, Anna; Murino, Vittorio; Cristani, Marco
2014-01-01
Individuals with Asperger syndrome/High Functioning Autism fail to spontaneously attribute mental states to the self and others, a life-long phenotypic characteristic known as mindblindness. We hypothesized that mindblindness would affect the dynamics of conversational interaction. Using generative models, in particular Gaussian mixture models and observed influence models, conversations were coded as interacting Markov processes, operating on novel speech/silence patterns, termed Steady Conversational Periods (SCPs). SCPs assume that whenever an agent's process changes state (e.g., from silence to speech), it causes a general transition of the entire conversational process, forcing inter-actant synchronization. SCPs fed into observed influence models, which captured the conversational dynamics of children and adolescents with Asperger syndrome/High Functioning Autism, and age-matched typically developing participants. Analyzing the parameters of the models by means of discriminative classifiers, the dialogs of patients were successfully distinguished from those of control participants. We conclude that meaning-free speech/silence sequences, reflecting inter-actant synchronization, at least partially encode typical and atypical conversational dynamics. This suggests a direct influence of theory of mind abilities onto basic speech initiative behavior.
NASA Astrophysics Data System (ADS)
Medland, A. J.; Zhu, Guowang; Gao, Jian; Sun, Jian
1996-03-01
Feature conversion, also called feature transformation and feature mapping, is defined as the process of converting features from one view of an object to another view of the object. In a relatively simple implementation, for each application the design features are automatically converted into features specific for that application. All modifications have to be made via the design features. This is the approach that has attracted most attention until now. In the ideal situation, however, conversions directly from application views to the design view, and to other applications views, are also possible. In this paper, some difficulties faced in feature conversion are discussed. A new representation scheme of feature-based parts models has been proposed for the purpose of one-way feature conversion. The parts models consist of five different levels of abstraction, extending from an assembly level and its attributes, single parts and their attributes, single features and their attributes, one containing the geometric reference element and finally one for detailed geometry. One implementation of feature conversion for rotational components within GT (Group Technology) has already been undertaken using an automated coding procedure operating on a design-feature database. This database has been generated by a feature-based design system, and the GT coding scheme used in this paper is a specific scheme created for a textile machine manufacturing plant. Such feature conversion techniques presented here are only in their early stages of development and further research is underway.
Property evolution during vitrification of dimethacrylate photopolymer networks
Abu-Elenain, Dalia; Lewis, Steven H.; Stansbury, Jeffrey W.
2013-01-01
Objectives This study seeks to correlate the interrelated properties of conversion, shrinkage, modulus and stress as dimethacrylate networks transition from rubbery to glassy states during photopolymerization. Methods An unfilled BisGMA/TEGDMA resin was photocured for various irradiation intervals (7–600 s) to provide controlled levels of immediate conversion, which was monitored continuously for 10 min. Fiber optic near-infrared spectroscopy permitted coupling of real-time conversion measurement with dynamic polymerization shrinkage (linometer), modulus (dynamic mechanical analyzer) and stress (tensometer) development profiles. Results The varied irradiation conditions produced final conversion ranging from 6 % to more than 60 %. Post-irradiation conversion (dark cure) was quite limited when photopolymerization was interrupted either at very low or very high levels of conversion while significant dark cure contributions were possible for photocuring reactions suspended within the post-gel, rubbery regime. Analysis of conversion-based property evolution during and subsequent to photocuring demonstrated that the shrinkage rate increased significantly at about 40 % conversion followed by late-stage suppression in the conversion-dependent shrinkage rate that begins at about 45–50 % conversion. The gradual vitrification process over this conversion range is evident based on the broad but well-defined inflection in the modulus versus conversion data. As limiting conversion is approached, modulus and, to a somewhat lesser extent, stress rise precipitously as a result of vitrification with the stress profile showing little if any late-stage suppression as seen with shrinkage. Significance Near the limiting conversion for this model resin, the volumetric polymerization shrinkage rate slows while an exponential rise in modulus promotes the vitrification process that appears to largely dictate stress development. PMID:24080378
Egli, Simone C; Beck, Irene R; Berres, Manfred; Foldi, Nancy S; Monsch, Andreas U; Sollberger, Marc
2014-10-01
It is unclear whether the predictive strength of established cognitive variables for progression to Alzheimer's disease (AD) dementia from mild cognitive impairment (MCI) varies depending on time to conversion. We investigated which cognitive variables were best predictors, and which of these variables remained predictive for patients with longer times to conversion. Seventy-five participants with MCI were assessed on measures of learning, memory, language, and executive function. Relative predictive strengths of these measures were analyzed using Cox regression models. Measures of word-list position-namely, serial position scores-together with Short Delay Free Recall of word-list learning best predicted conversion to AD dementia. However, only serial position scores predicted those participants with longer time to conversion. Results emphasize that the predictive strength of cognitive variables varies depending on time to conversion to dementia. Moreover, finer measures of learning captured by serial position scores were the most sensitive predictors of AD dementia. Copyright © 2014 The Alzheimer's Association. Published by Elsevier Inc. All rights reserved.
"Sex Is a sin": Afro-Caribbean Parent and Teen Perspectives on Sex Conversations.
Gabbidon, Kemesha S; Shaw-Ridley, Mary
2018-01-18
This study characterized (a) mothers' childhood and teenage experiences with sex conversations and (b) families' perceptions of current parent-child sex conversations within two underserved Afro-Caribbean communities in the U.S. Fourteen dyads comprised of Haitian and Jamaican mothers and teens (aged 14-18) living in Miami, Florida, completed semi-structured interviews sharing their experiences with sex conversations. Researchers analyzed data using thematic content analysis. Mothers' mean age was 41.85 years, (SD = 5.50) and teens' mean age was 16.35 years, (SD = 1.31). Most mothers reported forbidden or little childhood experiences with parent-child sex conversations. They affected their sexual attitudes, behaviors, and ability to discuss sex with their children. Although some mothers benefited from educational and skill development others shared fear-based messages with their children that some teens believed adversely affected the mother-child relationship quality. Culturally appropriate, skill-based approaches are necessary to improve families' communication self-efficacy for healthy sex conversations to occur in Afro-Caribbean families.
NASA Astrophysics Data System (ADS)
Badescu, Viorel; Landsberg, Peter T.
1995-08-01
The general theory developed in part I was applied to build up two models of photovoltaic conversion. To this end two different systems were analyzed. The first system consists of the whole absorber (converter), for which the balance equations for energy and entropy are written and then used to derive an upper bound for solar energy conversion. The second system covers a part of the absorber (converter), namely the valence and conduction electronic bands. The balance of energy is used in this case to derive, under additional assumptions, another upper limit for the conversion efficiency. This second system deals with the real location where the power is generated. Both models take into consideration the radiation polarization and reflection, and the effects of concentration. The second model yields a more accurate upper bound for the conversion efficiency. A generalized solar cell equation is derived. It is proved that other previous theories are particular cases of the present more general formalism.
NASA Technical Reports Server (NTRS)
Mei, Chuh; Pates, Carl S., III
1994-01-01
A coupled boundary element (BEM)-finite element (FEM) approach is presented to accurately model structure-acoustic interaction systems. The boundary element method is first applied to interior, two and three-dimensional acoustic domains with complex geometry configurations. Boundary element results are very accurate when compared with limited exact solutions. Structure-interaction problems are then analyzed with the coupled FEM-BEM method, where the finite element method models the structure and the boundary element method models the interior acoustic domain. The coupled analysis is compared with exact and experimental results for a simplistic model. Composite panels are analyzed and compared with isotropic results. The coupled method is then extended for random excitation. Random excitation results are compared with uncoupled results for isotropic and composite panels.
Real time infrared aerosol analyzer
Johnson, Stanley A.; Reedy, Gerald T.; Kumar, Romesh
1990-01-01
Apparatus for analyzing aerosols in essentially real time includes a virtual impactor which separates coarse particles from fine and ultrafine particles in an aerosol sample. The coarse and ultrafine particles are captured in PTFE filters, and the fine particles impact onto an internal light reflection element. The composition and quantity of the particles on the PTFE filter and on the internal reflection element are measured by alternately passing infrared light through the filter and the internal light reflection element, and analyzing the light through infrared spectrophotometry to identify the particles in the sample.
Analyzing the Dynamics of Communication in Online Social Networks
NASA Astrophysics Data System (ADS)
de Choudhury, Munmun; Sundaram, Hari; John, Ajita; Seligmann, Doree Duncan
This chapter deals with the analysis of interpersonal communication dynamics in online social networks and social media. Communication is central to the evolution of social systems. Today, the different online social sites feature variegated interactional affordances, ranging from blogging, micro-blogging, sharing media elements (i.e., image, video) as well as a rich set of social actions such as tagging, voting, commenting and so on. Consequently, these communication tools have begun to redefine the ways in which we exchange information or concepts, and how the media channels impact our online interactional behavior. Our central hypothesis is that such communication dynamics between individuals manifest themselves via two key aspects: the information or concept that is the content of communication, and the channel i.e., the media via which communication takes place. We present computational models and discuss large-scale quantitative observational studies for both these organizing ideas. First, we develop a computational framework to determine the "interestingness" property of conversations cented around rich media. Second, we present user models of diffusion of social actions and study the impact of homophily on the diffusion process. The outcome of this research is twofold. First, extensive empirical studies on datasets from YouTube have indicated that on rich media sites, the conversations that are deemed "interesting" appear to have consequential impact on the properties of the social network they are associated with: in terms of degree of participation of the individuals in future conversations, thematic diffusion as well as emergent cohesiveness in activity among the concerned participants in the network. Second, observational and computational studies on large social media datasets such as Twitter have indicated that diffusion of social actions in a network can be indicative of future information cascades. Besides, given a topic, these cascades are often a function of attribute homophily existent among the participants. We believe that this chapter can make significant contribution into a better understanding of how we communicate online and how it is redefining our collective sociological behavior.
NASA Astrophysics Data System (ADS)
Wang, Zujun; Xue, Yuanyuan; Guo, Xiaoqiang; Bian, Jingying; Yao, Zhibin; He, Baoping; Ma, Wuying; Sheng, Jiangkun; Dong, Guantao; Liu, Yan
2018-07-01
The conversion gain of the CMOS image sensor (CIS) is one of the most important key parameters to the CIS detector. The conversion gain degradation induced by radiation damage will seriously affect the performances of the CIS detector. The experiments of the CISs irradiated by protons, neutrons, and gamma rays are presented. The CISs have 4 Megapixels and pinned photodiode (PPD) pixel architecture with a standard 0.18 μm CMOS technology. The conversion gains versus the proton fluence (including the proton ionizing dose), neutron fluence and gamma total ionizing dose are presented, respectively. The mechanisms of the conversion gain degradation induced by radiation damage are analyzed in details. The investigations will help to improve the PPD CIS detector design, reliability and applicability for applications in the harsh radiation environments such as space and nuclear environments.
NASA Astrophysics Data System (ADS)
Fockaert, L. I.; Taheri, P.; Abrahami, S. T.; Boelen, B.; Terryn, H.; Mol, J. M. C.
2017-11-01
Zirconium-based conversion treatment of zinc, aluminium and magnesium oxides have been studied in-situ using ATR-FTIR in a Kretschmann geometry. This set-up was coupled to an electrochemical cell, which allowed to obtain chemical and electrochemical information simultaneously as a function of conversion time. This elucidated the strong relation between physico-chemical surface properties and zirconium-based conversion kinetics. Whereas the surface hydroxyl density of zinc and aluminium increased during conversion, magnesium (hydr)oxide was shown to dissolve in the acid solution. Due to this dissolution, strong surface alkalization can be expected, explaining the rapid conversion kinetics. AES depth profiling was used to determine the final oxide thickness and elemental composition. This confirmed that magnesium is most active and forms a zirconium oxide layer approximately 10 times thicker than zinc. On the other hand, the presence of zirconium oxide on aluminium is very low and can be considered as not fully covering the metal oxide. Additionally, the converted oxide chemistry was related to the bonding mechanisms of amide functionalized molecules using ATR-FTIR and XPS. It was shown that inclusion of zirconium altered the acid-base properties, increasing the substrate proton donating capabilities in case of magnesium oxide and increasing hydrogen bonding and Bronsted interactions due to increased surface hydroxide fractions on zinc and aluminium substrates.
Conversion and matched filter approximations for serial minimum-shift keyed modulation
NASA Technical Reports Server (NTRS)
Ziemer, R. E.; Ryan, C. R.; Stilwell, J. H.
1982-01-01
Serial minimum-shift keyed (MSK) modulation, a technique for generating and detecting MSK using series filtering, is ideally suited for high data rate applications provided the required conversion and matched filters can be closely approximated. Low-pass implementations of these filters as parallel inphase- and quadrature-mixer structures are characterized in this paper in terms of signal-to-noise ratio (SNR) degradation from ideal and envelope deviation. Several hardware implementation techniques utilizing microwave devices or lumped elements are presented. Optimization of parameter values results in realizations whose SNR degradation is less than 0.5 dB at error probabilities of .000001.
Cao, Wei; Liu, Dan; Zhang, Yi-Kai; Wang, Xiao-Yu; Chang, Yan-Rong; Yang, Qian; Wang, Si-Wang
2010-10-01
To analyze the content of proteins,amino acids and inorganic elements of Holotrichia diomphalia in different growing areas as the references for quality evaluation and reasonable application of them. The contents of proteins were determined using semi-micro Kjeldahl method. The contents of seventeen amino acids and inorganic elements were determined with amino acid analyzer and atomic absorption spectrometer and elemental analyzer, respectively. The contents of protein were 33.4%-44.4%, and that in Jiangxi were the highest in five different areas. There were seventeen kinds of amino acids in Holotrichia diomphalia. Among them, seven amino acids were essential to human life. The content of glutamic acid was the highest in seventeen amino acids. In inorganic elements, the content of Mg, Ca was higher in macroelements and Fe, Zn was higher in microelements. There are many kinds of necessary amino acids and inorganic elements for man kind in Holotrichia diomphalia. The contents of proteins, amino acids and inorganic elements have some difference in Holotrichia diomphalia of different growing areas.
Novel in situ resistance measurement for the investigation of CIGS growth in a selenization process
NASA Astrophysics Data System (ADS)
Liu, Wei; Tian, Jian-Guo; Li, Zu-Bin; He, Qing; Li, Feng-Yan; Li, Chang-Jian; Sun, Yun
2009-03-01
During the selenization process of CIGS thin films, the relation between the element loss rate and the precursor depositions are analyzed. The growth of the CIGS thin films during the selenization process is investigated by the novel in situ resistance measurement, by which the formation of compound semiconductors can be observed directly and simultaneously. Their structures, phase evolutions and element losses are analyzed by XRD and XRF. Based on the experimental results, it can be concluded that the phase transforms have nothing to do with the deposition sequences of precursors, while the element loss rates are related to the deposition sequences in this process. In addition, element loss mechanisms of CIGS thin films prepared by the selenization process are analyzed by the phase evolutions and chemical combined path in the In, Ga-Se reaction processes. Moreover it is verified that the element losses are depressed by increasing the ramping-up rate finally. The results provide effective methods to fabricate high-quality CIGS thin films with low element losses.
Loui, Hung; Brock, Billy C.
2016-10-25
The various embodiments presented herein relate to beam steering an array antenna by modifying intermediate frequency (IF) waveforms prior to conversion to RF signals. For each channel, a direct digital synthesis (DDS) component can be utilized to generate a waveform or modify amplitude, timing and phase of a waveform relative to another waveform, whereby the generation/modification can be performed prior to the IF input port of a mixer on each channel. A local oscillator (LO) signal can be utilized to commonly drive each of the mixers. After conversion at the RF output port of each of the mixers, each RF signal can be transmitted by a respective antenna element in the antenna array. Initiation of transmission of each RF signal can be performed simultaneously at each antenna. The process can be reversed during receive whereby timing, amplitude, and phase of the received can be modified digitally post ADC conversion.
Highly efficient frequency conversion with bandwidth compression of quantum light
Allgaier, Markus; Ansari, Vahid; Sansoni, Linda; Eigner, Christof; Quiring, Viktor; Ricken, Raimund; Harder, Georg; Brecht, Benjamin; Silberhorn, Christine
2017-01-01
Hybrid quantum networks rely on efficient interfacing of dissimilar quantum nodes, as elements based on parametric downconversion sources, quantum dots, colour centres or atoms are fundamentally different in their frequencies and bandwidths. Although pulse manipulation has been demonstrated in very different systems, to date no interface exists that provides both an efficient bandwidth compression and a substantial frequency translation at the same time. Here we demonstrate an engineered sum-frequency-conversion process in lithium niobate that achieves both goals. We convert pure photons at telecom wavelengths to the visible range while compressing the bandwidth by a factor of 7.47 under preservation of non-classical photon-number statistics. We achieve internal conversion efficiencies of 61.5%, significantly outperforming spectral filtering for bandwidth compression. Our system thus makes the connection between previously incompatible quantum systems as a step towards usable quantum networks. PMID:28134242
Review of the TREAT Conversion Conceptual Design and Fuel Qualification Plan
DOE Office of Scientific and Technical Information (OSTI.GOV)
Diamond, David
The U.S. Department of Energy (DOE) is preparing to re establish the capability to conduct transient testing of nuclear fuels at the Idaho National Laboratory (INL) Transient Reactor Test (TREAT) facility. The original TREAT core went critical in February 1959 and operated for more than 6,000 reactor startups before plant operations were suspended in 1994. DOE is now planning to restart the reactor using the plant's original high-enriched uranium (HEU) fuel. At the same time, the National Nuclear Security Administration (NNSA) Office of Material Management and Minimization Reactor Conversion Program is supporting analyses and fuel fabrication studies that will allowmore » for reactor conversion to low-enriched uranium (LEU) fuel (i.e., fuel with less than 20% by weight 235U content) after plant restart. The TREAT Conversion Program's objectives are to perform the design work necessary to generate an LEU replacement core, to restore the capability to fabricate TREAT fuel element assemblies, and to implement the physical and operational changes required to convert the TREAT facility to use LEU fuel.« less
Probing ultrafast ππ*/nπ* internal conversion in organic chromophores via K-edge resonant absorption
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wolf, T. J. A.; Myhre, R. H.; Cryan, J. P.
Many photoinduced processes including photosynthesis and human vision happen in organic molecules and involve coupled femtosecond dynamics of nuclei and electrons. Organic molecules with heteroatoms often possess an important excited-state relaxation channel from an optically allowed ππ* to a dark nπ* state. The ππ*/nπ* internal conversion is difficult to investigate, as most spectroscopic methods are not exclusively sensitive to changes in the excited-state electronic structure. Here, we report achieving the required sensitivity by exploiting the element and site specificity of near-edge soft X-ray absorption spectroscopy. As a hole forms in the n orbital during ππ*/nπ* internal conversion, the absorption spectrummore » at the heteroatom K-edge exhibits an additional resonance. We demonstrate the concept using the nucleobase thymine at the oxygen K-edge, and unambiguously show that ππ*/nπ* internal conversion takes place within (60 ± 30) fs. Furthermore, high-level-coupled cluster calculations confirm the method’s impressive electronic structure sensitivity for excited-state investigations.« less
Hsu, Shao-Hui; Li, Chun-Ting; Chien, Heng-Ta; Salunkhe, Rahul R.; Suzuki, Norihiro; Yamauchi, Yusuke; Ho, Kuo-Chuan; Wu, Kevin C.-W.
2014-01-01
We fabricated a highly efficient (with a solar-to-electricity conversion efficiency (η) of 8.1%) Pt-free dye-sensitized solar cell (DSSC). The counter electrode was made of cobalt sulfide (CoS) nanoparticles synthesized via surfactant-assisted preparation of a metal organic framework, ZIF-67, with controllable particle sizes (50 to 320 nm) and subsequent oxidation and sulfide conversion. In contrast to conventional Pt counter electrodes, the synthesized CoS nanoparticles exhibited higher external surface areas and roughness factors, as evidenced by X-ray diffraction (XRD), scanning electron microscopy (SEM) element mapping, and electrochemical analysis. Incident photon-to-current conversion efficiency (IPCE) results showed an increase in the open circuit voltage (VOC) and a decrease in the short-circuit photocurrent density (Jsc) for CoS-based DSSCs compared to Pt-based DSSCs, resulting in a similar power conversion efficiency. The CoS-based DSSC fabricated in the study show great potential for economically friendly production of Pt-free DSSCs. PMID:25382139
Probing ultrafast ππ*/nπ* internal conversion in organic chromophores via K-edge resonant absorption
Wolf, T. J. A.; Myhre, R. H.; Cryan, J. P.; ...
2017-06-22
Many photoinduced processes including photosynthesis and human vision happen in organic molecules and involve coupled femtosecond dynamics of nuclei and electrons. Organic molecules with heteroatoms often possess an important excited-state relaxation channel from an optically allowed ππ* to a dark nπ* state. The ππ*/nπ* internal conversion is difficult to investigate, as most spectroscopic methods are not exclusively sensitive to changes in the excited-state electronic structure. Here, we report achieving the required sensitivity by exploiting the element and site specificity of near-edge soft X-ray absorption spectroscopy. As a hole forms in the n orbital during ππ*/nπ* internal conversion, the absorption spectrummore » at the heteroatom K-edge exhibits an additional resonance. We demonstrate the concept using the nucleobase thymine at the oxygen K-edge, and unambiguously show that ππ*/nπ* internal conversion takes place within (60 ± 30) fs. Furthermore, high-level-coupled cluster calculations confirm the method’s impressive electronic structure sensitivity for excited-state investigations.« less
MHD compressor---expander conversion system integrated with GCR inside a deployable reflector
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tuninetti, G.; Botta, E.; Criscuolo, C.
1989-04-20
This work originates from the proposal MHD Compressor-Expander Conversion System Integrated with a GCR Inside a Deployable Reflector''. The proposal concerned an innovative concept of nuclear, closed-cycle MHD converter for power generation on space-based systems in the multi-megawatt range. The basic element of this converter is the Power Conversion Unit (PCU) consisting of a gas core reactor directly coupled to an MHD expansion channel. Integrated with the PCU, a deployable reflector provides reactivity control. The working fluid could be either uranium hexafluoride or a mixture of uranium hexafluoride and helium, added to enhance the heat transfer properties. The original Statementmore » of Work, which concerned the whole conversion system, was subsequently redirected and focused on the basic mechanisms of neutronics, reactivity control, ionization and electrical conductivity in the PCU. Furthermore, the study was required to be inherently generic such that the study was required to be inherently generic such that the analysis an results can be applied to various nuclear reactor and/or MHD channel designs''.« less
Hong, Wei; Huang, Dexiu; Zhang, Xinliang; Zhu, Guangxi
2007-12-24
All-optical on-off keying (OOK) to binary phase-shift keying (BPSK) modulation format conversion based on gain-transparent semiconductor optical amplifier (GT-SOA) is simulated and analyzed, where GT-SOA is used as an all-optical phase-modulator (PM). Numerical simulation of the phase modulation effect of GT-SOA is performed using a wideband dynamic model of GT-SOA and the quality of the BPSK signal is evaluated using the differential-phase-Q factor. Performance improvement by holding light injection is analyzed and non-return-to-zero (NRZ) and return-to-zero (RZ) modulation formats of the OOK signal are considered.
Measuring parameters of large-aperture crystals used for generating optical harmonics
DOE Office of Scientific and Technical Information (OSTI.GOV)
English, R. E.; Hibbard, R. L.; Michie, R. B.
1999-02-23
The purpose of this project was to develop tools for understanding the influence of crystal quality and crystal mounting on harmonic-generation efficiency at high irradiance. Measuring the homogeneity of crystals interferometrically, making detailed physics calculations of conversion efficiency, performing finite- element modeling of mounted crystals, and designing a new optical metrology tool were key elements in obtaining that understanding. For this work, we used the following frequency-tripling scheme: type I second- harmonic generation followed by type II sum-frequency mixing of the residual fundamental and the second harmonic light. The doubler was potassium dihydrogen phosphate (KDP), and the tripler was deuteratedmore » KDP (KD*P). With this scheme, near-infrared light (1053 nm) can be frequency tripled (to 351 nm) at high efficiency (theoretically >90%) for high irradiance (>3 GW/cm²). Spatial variations in the birefringence of the large crystals studied here (37 to 41 cm square by about 1 cm thick) imply that the ideal phase-matching orientation of the crystal with respect to the incident laser beam varies across the crystal. We have shown that phase-measuring interferometry can be used to measure these spatial variations. We observed transmitted wavefront differences between orthogonally polarized interferograms of {lambda}/50 to {lambda}/100, which correspond to index variations of order 10 -6. On some plates that we measured, the standard deviation of angular errors is 22-23 µrad; this corresponds to a 1% reduction in efficiency. Because these conversion crystals are relatively thin, their surfaces are not flat (deviate by k2.5 urn from flat). A crystal is mounted against a precision-machined surface that supports the crystal on four edges. This mounting surface is not flat either (deviates by +2.5 µm from flat). A retaining flange presses a compliant element against the crystal. The load thus applied near the edges of the crystal surface holds it in place. We performed detailed finite-element modeling to predict the resulting shape of the mounted crystal. The prediction agreed with measurements of mounted crystals. We computed the physics of the frequency-conversion process to better quantify the effects on efficiency of variation in the crystal' s axis, changes in the shape of the crystal, and mounting-induced stress. We were able to accurately predict the frequency-conversion performance of 37-cm square crystals on Beamlet, a one-beam scientific prototype of the NIF laser architecture, using interferometric measurements of the mounted crystals and the model. In a 2{omega} measurement campaign, the model predicted 64.9% conversion efficiency; 64.1% was observed. When detuned by 640 µrad, the model and measurement agreement is even better (both were 10.4%). Finally, we completed the design and initial testing of a new optical metrology tool to measure the spatial variation of frequency conversion. This system employs a high-power subaperture beam from a commercial laser oscillator and rod amplifier. The beam interrogates the crystal' s aperture by moving the crystal horizontally on a translation stage and translating the laser beam vertically on an optical periscope. Precision alignment is maintained by means of a full-aperture reference mirror, a precision-machined surface on the crystal mount, and autocollimators (the goal for angular errors is 10 µrad). The autocollimators track the mounting angle of the crystal and the direction of the laser beam with respect to the reference mirror. The conversion efficiency can be directly measured by recording l{omega}, 2{omega}, 3{omega} energy levels during the scan and by rocking (i.e., tilting) the crystal mount over an angular range.« less
Okolo, Chike; Malmstrom, Robert; Duncan, Karsten; Lopez, Julio
2015-09-01
Results of a study analyzing economic and clinical outcomes one year after conversion from thrice- to twice-daily pregabalin dosing for pain are presented. A retrospective chart review was conducted at two Veterans Affairs facilities. The analyzed population included all patients receiving pregabalin for pain whose dosing was converted from thrice- to twice-daily pregabalin dosing during a one-year period. The primary endpoint was the economic impact of the conversion. Secondary endpoints included reversion to thrice-daily pregabalin dosing, pregabalin discontinuation, addition of medications for pain, and unscheduled neuropathy-related visits. Among the 57 patients included in the data analysis, 41 continued to take pregabalin twice daily, 10 had pregabalin discontinued, and 6 had dosing reverted to thrice daily. The mean age of patients and the distribution of add-on pain medications did not differ significantly between patients whose pregabalin dosing frequency remained at twice daily and patients whose frequency reverted to thrice daily. The costs associated with pregabalin therapy differed significantly between the preconversion and postconversion periods. A savings of $115,867 was realized from this conversion for both facilities combined over the course of one year. In patients receiving pregabalin for pain, conversion from thrice- to twice-daily pregabalin dosing-while maintaining the same daily dose-resulted in substantial cost savings while having little effect on clinical outcomes. Copyright © 2015 by the American Society of Health-System Pharmacists, Inc. All rights reserved.
High-Precision Measurement of Eu/Eu* in Geological Glasses via LA-ICP-MS Analysis
NASA Technical Reports Server (NTRS)
Tang, Ming; McDonough, William F.; Arevalo, Ricardo, Jr.
2014-01-01
Elemental fractionation during laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis has been historically documented between refractory and volatile elements. In this work, however, we observed fractionation between light rare earth elements (LREEs) and heavy rare earth elements (HREEs) when using ablation strategies involving large spot sizes (greater than 100 millimeters) and line scanning mode. In addition: (1) ion yields decrease when using spot sizes above 100 millimeters; (2) (Eu/Eu*)(sub raw) (i.e. Europium anomaly) positively correlates with carrier gas (He) flow rate, which provides control over the particle size distribution of the aerosol reaching the ICP; (3) (Eu/Eu*)(sub raw) shows a positive correlation with spot size, and (4) the changes in REE signal intensity, induced by the He flow rate change, roughly correlate with REE condensation temperatures. The REE fractionation is likely driven by the slight but significant difference in their condensation temperatures. Large particles may not be completely dissociated in the ICP and result in preferential evaporation of the less refractory LREEs and thus non-stoichiometric particle-ion conversion. This mechanism may also be responsible for Sm-Eu-Gd fractionation as Eu is less refractory than Sm and Gd. The extent of fractionation depends upon the particle size distribution of the aerosol, which in turn is influenced by the laser parameters and matrix. Ablation pits and lines defined by low aspect ratios produce a higher proportion of large particles than high aspect ratio ablation, as confirmed by measurements of particle size distribution in the laser induced aerosol. Therefore, low aspect ratio ablation introduces particles that cannot be decomposed and/or atomized by the ICP and thus results in exacerbated elemental fractionation. Accurate quantification of REE concentrations and Eu/Eu* requires reduction of large particle production during laser ablation. For the reference materials analyzed in this work, the 100 millimeters spot measurements of Eu/Eu* agreed with GeoRem preferred values within 3 percent. Our long-term analyses of Eu/Eu* in MPI-DING glass KL-2G and USGS glass BIR-1G were reproducible at 3 percent (2 RSD).
Property evolution during vitrification of dimethacrylate photopolymer networks.
Abu-elenain, Dalia A; Lewis, Steven H; Stansbury, Jeffrey W
2013-11-01
This study seeks to correlate the interrelated properties of conversion, shrinkage, modulus and stress as dimethacrylate networks transition from rubbery to glassy states during photopolymerization. An unfilled BisGMA/TEGDMA resin was photocured for various irradiation intervals (7-600 s) to provide controlled levels of immediate conversion, which was monitored continuously for 10 min. Fiber optic near-infrared spectroscopy permitted coupling of real-time conversion measurement with dynamic polymerization shrinkage (linometer), modulus (dynamic mechanical analyzer) and stress (tensometer) development profiles. The varied irradiation conditions produced final conversion ranging from 6% to more than 60%. Post-irradiation conversion (dark cure) was quite limited when photopolymerization was interrupted either at very low or very high levels of conversion while significant dark cure contributions were possible for photocuring reactions suspended within the post-gel, rubbery regime. Analysis of conversion-based property evolution during and subsequent to photocuring demonstrated that the shrinkage rate increased significantly at about 40% conversion followed by late-stage suppression in the conversion-dependent shrinkage rate that begins at about 45-50% conversion. The gradual vitrification process over this conversion range is evident based on the broad but well-defined inflection in the modulus versus conversion data. As limiting conversion is approached, modulus and, to a somewhat lesser extent, stress rise precipitously as a result of vitrification with the stress profile showing little if any late-stage suppression as seen with shrinkage. Near the limiting conversion for this model resin, the volumetric polymerization shrinkage rate slows while an exponential rise in modulus promotes the vitrification process that appears to largely dictate stress development. Copyright © 2013 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.
Conversion of Carbon Dioxide into Ethanol by Electrochemical Synthesis Method Using Cu-Zn Electrode
NASA Astrophysics Data System (ADS)
Riyanto; Ramadan, S.; Fariduddin, S.; Aminudin, A. R.; Hayatri, A. K.
2018-01-01
Research on conversion of carbon dioxide into ethanol has been done. The conversion process is carried out in a sodium bicarbonate electrolyte solution in an electrochemical synthesis reactor. As cathode was used Cu-Zn, while as anode carbon was utilized. Variations of voltage, concentration of sodium bicarbonate electrolyte solution and time of electrolysis were performed to determine the optimum conditions to convert carbon dioxide into ethanol. Sample of the electrochemical synthesis process was analyzed by gas chromatography. From the result, it is found that the optimum conditions of the electrochemical synthesis process of carbon dioxide conversion into ethanol are voltage, concentration of sodium bicarbonate electrolyte solution and time of electrolysis are 3 volts, 0.4 M and 90 minutes with the ethanol concentration of 10.44%.
Communication nonaccommodation in family conversations about end-of-life health decisions.
Scott, Allison M; Caughlin, John P
2015-01-01
Furthering our understanding of how communication can improve end-of-life decision making requires a shift in focus from whether people talk to how people talk about end-of-life health decisions. This study used communication accommodation theory to examine the extent to which communication nonaccommodation distinguished more from less successful end-of-life conversations among family members. We analyzed elicited conversations about end-of-life health decisions from 121 older parent/adult child dyads using outside ratings of communication over- and underaccommodation and self-reported conversational outcomes. Results of multilevel linear modeling revealed that outside ratings of underaccommodation predicted self-reported and partner-reported uncertainty, and ratings of overaccommodation predicted self-reported decision-making efficacy and change in concordance accuracy. We discuss the methodological, theoretical, and practical implications of these findings.
Telling Stories of Violence in Adult ESL Classrooms: Disrupting Safe Spaces
ERIC Educational Resources Information Center
Waterhouse, Monica
2016-01-01
This article develops a complex understanding of safe space in relation to adult refugee learners' oral literacy practice of telling stories of violent life experiences in English as a second language (ESL) classrooms. A rhizoanalytic approach brings theoretical and empirical elements into conversation to ask two questions. Can the exigencies of…
Optimization of SIS mixer elements
NASA Technical Reports Server (NTRS)
Mattauch, Robert J.
1985-01-01
Superconductor-Insulator-Superconductor (SIS) quantum mixers provide an approach to millimeter wave mixing - potentially offering conversion gain, a low local oscillator power demand, and potential mixer noise temperatures near the quantum limit. The development of a reliable fabrication technology for producing such high quality SIS devices for mixer applications in radio astronomy is the focus of the work.
The increasing use of silver (Ag) nanoparticles [containing either elemental Ag (Ag-NPs) or AgCl (AgCl-NPs)] in commercial products such as textiles will most likely result in these materials reaching wastewater treatment plants. Previous studies indicate that a conversion of Ag-...
USDA-ARS?s Scientific Manuscript database
Mineral concentration of plant biomass can affect its use in thermal conversion to energy. The objective of this study was to compare the precision and accuracy of university and private laboratories that conduct mineral analyses of plant biomass on a fee basis. Accuracy and precision of the laborat...
Fate of higher-mass elements and surface functional groups during the pyrolysis of waste pecan shell
USDA-ARS?s Scientific Manuscript database
Thermochemical conversion of agricultural wastes to bioenergy has a potential to play forefront roles within the context of food, energy, and water nexus. Biochar solid product of pyrolysis is a promising tool to manage food crop production and water resources by means of soil amendment. The goal ...
ERIC Educational Resources Information Center
Wang, Wei
2017-01-01
This study investigates Mandarin discourse markers from both functional and prosodic perspectives. Discourse markers are defined as sequentially dependent elements which bracket units of talk (Schiffrin 1987). In this study, I focus on three discourse markers, "ranhou" "then", "wo juede" "I think/feel", and…
Making Our White Selves Intelligible to Ourselves: Implications for Teacher Education.
ERIC Educational Resources Information Center
Mazzei, Lisa A.
This study engaged the narratives and conversations of five white teachers in an urban school district as they explored the implications associated with seeing themselves as raced individuals. It also explored how an awareness of these narratives shaped the instructional environment created by these teachers. An important element in the analysis…
Orienting to Third-Party Conversations
ERIC Educational Resources Information Center
Martinez-Sussmann, Carmen; Akhtar, Nameera; Diesendruck, Gil; Markson, Lori
2011-01-01
Children as young as two years of age are able to learn novel object labels through overhearing, even when distracted by an attractive toy (Akhtar, 2005). The present studies varied the information provided about novel objects and examined which elements (i.e. novel versus neutral information and labels versus facts) toddlers chose to monitor, and…
College Writing: A Personal Approach to Academic Writing. Third Edition.
ERIC Educational Resources Information Center
Fulwiler, Toby
The affirmation of individual creativity in writing is what sets this book apart from other process-oriented rhetorics. Conversational in tone, the book's third edition boasts a writer-to-writer perspective that will put students at ease. The book "walks" students through the main elements of writing from discovery and research to…
Johansson, Monica Blom; Carlsson, Marianne; Sonnander, Karin
2012-01-01
To enhance communicative ability and thereby the possibility of increased participation of persons with aphasia, the use of communication strategies has been proposed. However, little is known about how persons with aphasia experience having conversations and how they perceive their own and their conversation partner's use of communication strategies. To explore how people with aphasia experience having conversations, how they handle communication difficulties, and how they perceive their own and their communication partners' use of communication strategies. Semi-structured interviews were conducted with four women and seven men with chronic aphasia (n = 11). Interviews were video-recorded, transcribed verbatim and analysed by qualitative content analysis. Informants appreciated having conversations despite the fact that they perceived their aphasia as a serious hindrance. Different factors related to the informants, the conversation partners, the conversation itself and the physical environment were perceived to impact on conversations. The importance of the communication partners' knowledge and understanding of aphasia and their use of supporting conversation strategies were acknowledged by the informants. The informants' views on using communication aid devices or strategies varied considerably. Four themes that characterized the informants' narratives were: loss and frustration, fear and uncertainty, shared responsibility based on knowledge, and longing for the past or moving forward. The informants longed to regain their former language ability and role as an active participant in society. To enhance participation of persons with aphasia, it is suggested that communication partner training should be an important and integral part of aphasia rehabilitation. Important elements of such training are reflecting on communication behaviours, training in real-life situations, and acknowledging each individual's special needs and preferences. To deal with the consequences of aphasia, counselling and psychological support may be needed. © 2011 Royal College of Speech & Language Therapists.
Stans, Steffy E A; Dalemans, Ruth J P; de Witte, Luc P; Smeets, Hester W H; Beurskens, Anna J
2017-12-01
The role of the physical environment in communication between health-care professionals and persons with communication problems is a neglected area. This study provides an overview of factors in the physical environment that play a role in communication during conversations between people who are communication vulnerable and health-care professionals. A scoping review was conducted using the methodological framework of Arksey and O'Malley. The PubMed, PsycINFO, CINAHL and Cochrane Library databases were screened, and a descriptive and thematic analysis was completed. Sixteen publications were included. Six factors in the physical environment play a role in conversations between people who are communication vulnerable and health-care professionals: (1) lighting, (2) acoustic environment, (3) humidity and temperature, (4) setting and furniture placement, (5) written information, and (6) availability of augmentative and alternative communication (AAC) tools. These factors indicated barriers and strategies related to the quality of these conversations. Relatively small and simple strategies to adjust the physical environment (such as adequate lighting, quiet environment, providing pen and paper) can support people who are communication vulnerable to be more involved in conversations. It is recommended that health-care professionals have an overall awareness of the potential influence of environmental elements on conversations. Implications for rehabilitation The physical environment is an important feature in the success or disturbance of communication. Small adjustments to the physical environment in rehabilitation can contribute to a communication-friendly environment for conversations with people who are communication vulnerable. Professionals should consider adjustments with regard to the following factors in the physical environment during conversations with people who are communication vulnerable: lighting, acoustic environment, humidity and temperature, setting and furniture placement, written information, and availability of AAC (augmentative and alternative communication tools).
Three-Dimensional Finite-Element Simulation for a Thermoelectric Generator Module
NASA Astrophysics Data System (ADS)
Hu, Xiaokai; Takazawa, Hiroyuki; Nagase, Kazuo; Ohta, Michihiro; Yamamoto, Atsushi
2015-10-01
A three-dimensional closed-circuit numerical model of a thermoelectric generator (TEG) module has been constructed with COMSOL® Multiphysics to verify a module test system. The Seebeck, Peltier, and Thomson effects and Joule heating are included in the thermoelectric conversion model. The TEG model is employed to simulate the operation of a 16-leg TEG module based on bismuth telluride with temperature-dependent material properties. The module is mounted on a test platform, and simulated by combining the heat conduction process and thermoelectric conversion process. Simulation results are obtained for the terminal voltage, output power, heat flow, and efficiency as functions of the electric current; the results are compared with measurement data. The Joule and Thomson heats in all the thermoelectric legs, as functions of the electric current, are calculated by finite-element volume integration over the entire legs. The Peltier heat being pumped at the hot side and released at the cold side of the module are also presented in relation to the electric current. The energy balance relations between heat and electricity are verified to support the simulation.
Steady-State Thermal-Hydraulics Analyses for the Conversion of BR2 to Low Enriched Uranium Fuel
DOE Office of Scientific and Technical Information (OSTI.GOV)
Licht, J.; Bergeron, A.; Dionne, B.
The code PLTEMP/ANL version 4.2 was used to perform the steady-state thermal-hydraulic analyses of the BR2 research reactor for conversion from Highly-Enriched to Low Enriched Uranium fuel (HEU and LEU, respectively). Calculations were performed to evaluate different fuel assemblies with respect to the onset of nucleate boiling (ONB), flow instability (FI), critical heat flux (CHF) and fuel temperature at beginning of cycle conditions. The fuel assemblies were characteristic of fresh fuel (0% burnup), highest heat flux (16% burnup), highest power (32% burnup) and highest burnup (46% burnup). Results show that the high heat flux fuel element is limiting for ONB,more » FI, and CHF, for both HEU and LEU fuel, but that the high power fuel element produces similar margin in a few cases. The maximum fuel temperature similarly occurs in both the high heat flux and high power fuel assemblies for both HEU and LEU fuel. A sensitivity study was also performed to evaluate the variation in fuel temperature due to uncertainties in the thermal conductivity degradation associated with burnup.« less
The Use of Lead Isotope and Rare Earth Element Geochemistry for Forensic Geographic Provenancing
NASA Astrophysics Data System (ADS)
Carey, A.; Darrah, T.; Harrold, Z.; Prutsman-Pfeiffer, J.; Poreda, R.
2008-12-01
Lead isotope and rare earth element composition of modern human bones are analyzed to explore their utility for geographical provenancing. DNA analysis is the standard for identification of individuals. DNA analysis requires a DNA match for comparison. Thus, DNA analysis is of limited use in cases involving unknown remains. Trace elements are incorporated into bones and teeth during biomineralization, recording the characteristics of an individual's geochemical environment. Teeth form during adolescence, recording the geochemical environment of an individual's youth. Bones remodel throughout an individual's lifetime. Bones consist of two types of bone tissue (cortical and trabecular) that remodel at different rates, recording the geochemical environment at the time of biomineralization. Cortical bone tissue, forming the outer surface of bones, is dense, hard tissue that remodels in 25-30 yrs. Conversely, trabecular bone tissue, the inner cavity of bones, is low density, porous and remodels in 2-5 years. Thus, analyzing teeth and both bone tissues allows for the development of a geographical time line capable of tracking immigration patterns through time instead of only an individual's youth. Geochemical isotopic techniques (Sr, O, C, N) have been used for geographical provenancing in physical anthropology. The isotopic values of Sr, C, O, N are predominantly a function of soil compositions in areas where food is grown or water is consumed. Application of these provenancing techniques has become difficult as an individual's diet may reflect the isotopic composition of foods obtained at the local grocer as opposed to local soil compositions. Thus, we explore the use of REEs and Pb isotopes for geographical provenancing. Pb and REEs are likely more reliable indicators of modern geographical location as their composition are high in bio-available sources such as local soils, atmospheric aerosols, and dust as opposed to Sr, C, O, N that are controlled by food and drinking water. Lead isotope and REE analysis of trabecular and cortical bone tissue of 60 femoral heads resected during hip replacement surgery at the Univ. of Roch. Medical Center were analyzed by a combination of TIMS and ICP-MS. Results show that Pb compositions are consistent with local soil with variable inputs from known environmental sources. Several samples demonstrate inputs from known environmental sources (e.g. Mississippi Valley ore) that was used in paint, solder, and US gasoline. Additionally, results suggest bioincorporation of Pb with isotopic composition consistent with that observed for Canadian gasoline aerosols. Immigrants included in the study show Pb compositions distinctly different than local residents.
NASA Astrophysics Data System (ADS)
Ozturk, H.; Altinpinar, M.
2017-07-01
The point load (PL) test is generally used for estimation of uniaxial compressive strength (UCS) of rocks because of its economic advantages and simplicity in testing. If the PL index of a specimen is known, the UCS can be estimated using conversion factors. Several conversion factors have been proposed by various researchers and they are dependent upon the rock type. In the literature, conversion factors on different sedimentary, igneous and metamorphic rocks can be found, but no study exists on trona. In this study, laboratory UCS and field PL tests were carried out on trona and interbeds of volcano-sedimentary rocks. Based on these tests, PL to UCS conversion factors of trona and interbeds are proposed. The tests were modeled numerically using a distinct element method (DEM) software, particle flow code (PFC), in an attempt to guide researchers having various types of modeling problems (excavation, cavern design, hydraulic fracturing, etc.) of the abovementioned rock types. Average PFC parallel bond contact model micro properties for the trona and interbeds were determined within this study so that future researchers can use them to avoid the rigorous PFC calibration procedure. It was observed that PFC overestimates the tensile strength of the rocks by a factor that ranges from 22 to 106.
Bioinspired model of mechanical energy harvesting based on flexoelectric membranes.
Rey, Alejandro D; Servio, P; Herrera-Valencia, E E
2013-02-01
Membrane flexoelectricity is an electromechanical coupling process that describes membrane electrical polarization due to bending and membrane bending under electric fields. In this paper we propose, formulate, and characterize a mechanical energy harvesting system consisting of a deformable soft flexoelectric thin membrane subjected to harmonic forcing from contacting bulk fluids. The key elements of the energy harvester are formulated and characterized, including (i) the mechanical-to-electrical energy conversion efficiency, (ii) the electromechanical shape equation connecting fluid forces with membrane curvature and electric displacement, and (iii) the electric power generation and efficiency. The energy conversion efficiency is cast as the ratio of flexoelectric coupling to the product of electric and bending elasticity. The device is described by a second-order curvature dynamics coupled to the electric displacement equation and as such results in mechanical power absorption with a resonant peak whose amplitude decreases with bending viscosity. The electric power generation is proportional to the conversion factor and the power efficiency decreases with frequency. Under high bending viscosity, the power efficiency increases with the conversion factor and under low viscosities it decreases with the conversion factor. The theoretical results presented contribute to the ongoing experimental efforts to develop mechanical energy harvesting from fluid flow energy through solid-fluid interactions and electromechanical transduction.
NASA Astrophysics Data System (ADS)
Eriyusni, N.; Siregar, A. Z.
2018-02-01
Lake Laut Tawar is located in Aceh district of Aceh province. The lake were used by the community as a livelihood by making a Cages. One of the elements that influence the fish growth is an element Phosphate (PO4) and other such as, pH, nitrate-nitrite, temperature and others. The lake has undergone changes caused by the use of commercial feed. The sampling locations based on the environmental setting by using method "purposive sampling" from January to May. The results was found of 0.1407 mg/L phosphate with fish expenditure amounting to 23728.61 ton / year using cages of net with number as 92, stocking density at 48,950 of fish and marine area 19.77 Ha. However the standard classes showed is under class II Regulation with No. 82 Year 2001 3400, solid lowest stocking cages tail on the size of 2.5 x 2.5 x 3M (spacious, 181m3) with post-harvest fish expenditure amounted to 1,214 tons of fish/year, the highest 9,250 cages tail on the size e of 5 x 5 x 3m (spacious 123m3) with fish expenditure by 2,800 tones of fish/year. While the results of feed conversion and Phosphate content is 12.70% with the Feed Conversion Ratio (FCR) was 1,635 and 1,491.
Wave front engineering by means of diffractive optical elements for applications in microscopy
NASA Astrophysics Data System (ADS)
Cojoc, Dan; Ferrari, Enrico; Garbin, Valeria; Cabrini, Stefano; Carpentiero, Alessandro; Prasciolu, Mauro; Businaro, Luca; Kaulich, Burchard; Di Fabrizio, Enzo
2006-05-01
We present a unified view regarding the use of diffractive optical elements (DOEs) for microscopy applications a wide range of electromagnetic spectrum. The unified treatment is realized through the design and fabrication of DOE through which wave front beam shaping is obtained. In particular we show applications ranging from micromanipulation using optical tweezers to X-ray differential interference contrast (DIC) microscopy. We report some details on the design and physical implementation of diffractive elements that beside focusing perform also other optical functions: beam splitting, beam intensity and phase redistribution or mode conversion. Laser beam splitting is used for multiple trapping and independent manipulation of spherical micro beads and for direct trapping and manipulation of biological cells with non-spherical shapes. Another application is the Gauss to Laguerre-Gaussian mode conversion, which allows to trap and transfer orbital angular momentum of light to micro particles with high refractive index and to trap and manipulate low index particles. These experiments are performed in an inverted optical microscope coupled with an infrared laser beam and a spatial light modulator for DOEs implementation. High resolution optics, fabricated by means of e-beam lithography, are demonstrated to control the intensity and the phase of the sheared beams in X-ray DIC microscopy. DIC experiments with phase objects reveal a dramatic increase in image contrast compared to bright-field X-ray microscopy.
Protecting health care workers from tuberculosis: a 10-year experience.
Welbel, Sharon F; French, Audrey L; Bush, Patricia; DeGuzman, Delia; Weinstein, Robert A
2009-10-01
Cook County Hospital (CCH) is an inner-city, large public hospital. Twenty-five percent of Chicago's tuberculosis (TB) cases are diagnosed at CCH. We wanted to review and analyze interventions implemented over a 10-year period at CCH to prevent TB infection in health care workers. We performed a retrospective review of interventions to prevent health care-associated tuberculosis. We collated and analyzed tuberculin skin test conversions in our employees for the same time period. From 1990 to 2002, we cared for over 1800 in-patients with tuberculosis. During 1992-1997, multiple interventions to eliminate health care-associated spread of tuberculosis were implemented. Tuberculin skin test conversions in our employees decreased markedly from January 1994 through December 2002. Two drops in tuberculin skin test conversion rates occurred: one after introduction of basic administrative and engineering controls and a second after we experienced a decrease in missed TB cases and the introduction of N-95 personal respirators with 1-time qualitative fit testing. Our annual health care worker skin test conversion rate fell significantly when our primary interventions were relatively simple administrative and engineering controls. Educating health care workers to promptly recognize patients with TB and placing exhaust fans to create negative-pressure respiratory isolation rooms were probably our 2 most potent infection control measures.
Cogeneration technology alternatives study. Volume 1: Summary report
NASA Technical Reports Server (NTRS)
1980-01-01
Data and information in the area of advanced energy conversion systems for industrial congeneration applications in the 1985-2000 time period was studied. Six current and thirty-one advanced energy conversion systems were defined and combined with appropriate balance-of-plant equipment. Twenty-six industrial processes were selected from among the high energy consuming industries to serve as a framework for the study. Each conversion system was analyzed as a cogenerator with each industrial plant. Fuel consumption, costs, and environmental intrusion were evaluated and compared to corresponding traditional values. Various cogeneration strategies were analyzed and both topping and bottoming (using industrial by-product heat) applications were included. The advanced energy conversion technologies indicated reduced fuel consumption, costs, and emissions. Typically fuel energy savings of 10 to 25 percent were predicted compared to traditional on-site furnaces and utility electricity. With the variety of industrial requirements, each advanced technology had attractive applications. Overall, fuel cells indicated the greatest fuel energy savings and emission reductions. Gas turbines and combined cycles indicated high overall annual cost savings. Steam turbines and gas turbines produced high estimated returns. In some applications, diesels were most efficient. The advanced technologies used coal-derived fuels, or coal with advanced fluid bed combustion or on-site gasification systems.
Coevolution of Siglec-11 and Siglec-16 via gene conversion in primates.
Hayakawa, Toshiyuki; Khedri, Zahra; Schwarz, Flavio; Landig, Corinna; Liang, Suh-Yuen; Yu, Hai; Chen, Xi; Fujito, Naoko T; Satta, Yoko; Varki, Ajit; Angata, Takashi
2017-11-23
Siglecs-11 and -16 are members of the sialic acid recognizing Ig-like lectin family, and expressed in same cells. Siglec-11 functions as an inhibitory receptor, whereas Siglec-16 exhibits activating properties. In humans, SIGLEC11 and SIGLEC16 gene sequences are extremely similar in the region encoding the extracellular domain due to gene conversions. Human SIGLEC11 was converted by the nonfunctional SIGLEC16P allele, and the converted SIGLEC11 allele became fixed in humans, possibly because it provides novel neuroprotective functions in brain microglia. However, the detailed evolutionary history of SIGLEC11 and SIGLEC16 in other primates remains unclear. We analyzed SIGLEC11 and SIGLEC16 gene sequences of multiple primate species, and examined glycan binding profiles of these Siglecs. The phylogenetic tree demonstrated that gene conversions between SIGLEC11 and SIGLEC16 occurred in the region including the exon encoding the sialic acid binding domain in every primate examined. Functional assays showed that glycan binding preference is similar between Siglec-11 and Siglec-16 in all analyzed hominid species. Taken together with the fact that Siglec-11 and Siglec-16 are expressed in the same cells, Siglec-11 and Siglec-16 are regarded as paired receptors that have maintained similar ligand binding preferences via gene conversions. Relaxed functional constraints were detected on the SIGLEC11 and SIGLEC16 exons that underwent gene conversions, possibly contributing to the evolutionary acceptance of repeated gene conversions. The frequency of nonfunctional SIGLEC16P alleles is much higher than that of SIGLEC16 alleles in every human population. Our findings indicate that Siglec-11 and Siglec-16 have been maintained as paired receptors by repeated gene conversions under relaxed functional constraints in the primate lineage. The high prevalence of the nonfunctional SIGLEC16P allele and the fixation of the converted SIGLEC11 imply that the loss of Siglec-16 and the gain of Siglec-11 in microglia might have been favored during the evolution of human lineage.
NASA Astrophysics Data System (ADS)
Li, Chun-Hao; Tsai, Ming-Jong
2009-06-01
A novel diode-pumped Nd:YAG laser system that employs a fixed active laser medium and a pair of quick-change output couplers on a precision linear stage for 1064 or 532 nm wavelength generation is presented. Fixed elements include a rear mirror, an acousto-optical Q-switch, and a diode-pumped solid-state laser (DPSSL). Movable elements for 1064 nm generation include an intra-cavity aperture as a mode selection element (MSE) and an output coupler. Movable elements for 532 nm generation include an intra-cavity frequency conversion with KTP, an intra-cavity aperture as a mode selection element (MSE), and an output coupler. Under stable operating conditions, the 1064 nm configuration produced a beam propagation ratio of 1.18 whereas the 532 nm configuration produced a beam propagation ratio of 1.1, both of which used an intra-cavity MSE with an aperture of 1.2 mm and a length of 5 mm.
Dispersoid reinforced alloy powder and method of making
Anderson, Iver E; Rieken, Joel
2013-12-10
A method of making dispersion-strengthened alloy particles involves melting an alloy having a corrosion and/or oxidation resistance-imparting alloying element, a dispersoid-forming element, and a matrix metal wherein the dispersoid-forming element exhibits a greater tendency to react with an introduced reactive species than does the alloying element and wherein one or more atomizing parameters is/are modified to controllably reduce the amount of the reactive species, such as oxygen, introduced into the atomized particles so as to reduce anneal times and improve reaction (conversion) to the desired strengthening dispersoids in the matrix. The atomized alloy particles are solidified as solidified alloy particles or as a solidified deposit of alloy particles. Bodies are made from the dispersion strengthened alloy particles, deposit thereof, exhibit enhanced fatigue and creep resistance and reduced wear as well as enhanced corrosion and/or oxidation resistance at high temperatures by virtue of the presence of the corrosion and/or oxidation resistance imparting alloying element in solid solution in the particle alloy matrix.
Kehrig, Helena A; Hauser-Davis, Rachel A; Seixas, Tércia G; Fillmann, Gilberto
2015-07-15
Magellanic penguins have been reported as good biomonitors for several types of pollutants, including trace-elements. In this context, selenium (Se), total mercury, methylmercury, inorganic mercury (Hg(inorg)), cadmium (Cd) and lead (Pb), as well as metallothionein (MT) levels, were evaluated in the feathers, liver and kidney of juvenile Magellanic penguins found stranded along the coast of Southern Brazil. The highest concentrations of all trace-elements and methylmercury were found in internal organs. Concentrations of Cd and Se in feathers were extremely low in comparison with their concentrations in soft tissues. The results showed that both Se and MT are involved in the detoxification of trace-elements (Cd, Pb and Hg(inorg)) since statistically significant relationships were found in liver. Conversely, hepatic Se was shown to be the only detoxifying agent for methylmercury. Copyright © 2015 Elsevier Ltd. All rights reserved.
III-V arsenide-nitride semiconductor
NASA Technical Reports Server (NTRS)
Major, Jo S. (Inventor); Welch, David F. (Inventor); Scifres, Donald R. (Inventor)
2000-01-01
III-V arsenide-nitride semiconductor are disclosed. Group III elements are combined with group V elements, including at least nitrogen and arsenic, in concentrations chosen to lattice match commercially available crystalline substrates. Epitaxial growth of these III-V crystals results in direct bandgap materials, which can be used in applications such as light emitting diodes and lasers. Varying the concentrations of the elements in the III-V materials varies the bandgaps, such that materials emitting light spanning the visible spectra, as well as mid-IR and near-UV emitters, can be created. Conversely, such material can be used to create devices that acquire light and convert the light to electricity, for applications such as full color photodetectors and solar energy collectors. The growth of the III-V material can be accomplished by growing thin layers of elements or compounds in sequences that result in the overall lattice match and bandgap desired.
Methods for forming group III-arsenide-nitride semiconductor materials
NASA Technical Reports Server (NTRS)
Major, Jo S. (Inventor); Welch, David F. (Inventor); Scifres, Donald R. (Inventor)
2002-01-01
Methods are disclosed for forming Group III-arsenide-nitride semiconductor materials. Group III elements are combined with group V elements, including at least nitrogen and arsenic, in concentrations chosen to lattice match commercially available crystalline substrates. Epitaxial growth of these III-V crystals results in direct bandgap materials, which can be used in applications such as light emitting diodes and lasers. Varying the concentrations of the elements in the III-V crystals varies the bandgaps, such that materials emitting light spanning the visible spectra, as well as mid-IR and near-UV emitters, can be created. Conversely, such material can be used to create devices that acquire light and convert the light to electricity, for applications such as full color photodetectors and solar energy collectors. The growth of the III-V crystals can be accomplished by growing thin layers of elements or compounds in sequences that result in the overall lattice match and bandgap desired.
Methods for forming group III-V arsenide-nitride semiconductor materials
NASA Technical Reports Server (NTRS)
Major, Jo S. (Inventor); Welch, David F. (Inventor); Scifres, Donald R. (Inventor)
2000-01-01
Methods are disclosed for forming Group III--arsenide-nitride semiconductor materials. Group III elements are combined with group V elements, including at least nitrogen and arsenic, in concentrations chosen to lattice match commercially available crystalline substrates. Epitaxial growth of these III-V crystals results in direct bandgap materials, which can be used in applications such as light emitting diodes and lasers. Varying the concentrations of the elements in the III-V crystals varies the bandgaps, such that materials emitting light spanning the visible spectra, as well as mid-IR and near-UV emitters, can be created. Conversely, such material can be used to create devices that acquire light and convert the light to electricity, for applications such as full color photodetectors and solar energy collectors. The growth of the III-V crystals can be accomplished by growing thin layers of elements or compounds in sequences that result in the overall lattice match and bandgap desired.
Direct mounted photovoltaic device with improved adhesion and method thereof
Boven, Michelle L; Keenihan, James R; Lickly, Stan; Brown, Jr., Claude; Cleereman, Robert J; Plum, Timothy C
2014-12-23
The present invention is premised upon a photovoltaic device suitable for directly mounting on a structure. The device includes an active portion including a photovoltaic cell assembly having a top surface portion that allows transmission of light energy to a photoactive portion of the photovoltaic device for conversion into electrical energy and a bottom surface having a bottom bonding zone; and an inactive portion immediately adjacent to and connected to the active portion, the inactive portion having a region for receiving a fastener to connect the device to the structure and having on a top surface, a top bonding zone; wherein one of the top and bottom bonding zones comprises a first bonding element and the other comprises a second bonding element, the second bonding element designed to interact with the first bonding element on a vertically overlapped adjacent photovoltaic device to bond the device to such adjacent device or to the structure.
UNCERTAINTY IN SCALING NUTRIENT EXPORT COEFFICIENTS
The Innov-X XT400 portable XRF analyzer features a miniature, rugged x-ray tube excitation source for analyzing a wide variety of elements and sample materials, including alloys, environmental solids, and other analytical samples. The x-ray tube source and Light Element Analysis...
Influence of Hemostatic Solution on Bond Strength and Physicochemical Properties of Resin Cement.
Araújo, Isabela Sousa de; Prado, Célio Jesus do; Raposo, Luís Henrique Araújo; Soares, Carlos José; Zanatta, Rayssa Ferreira; Torres, Carlos Rocha Gomes; Ruggiero, Reinaldo; Silva, Gisele Rodrigues da
2017-01-01
The aim of this study was to evaluate the degree of conversion, color stability, chemical composition, and bond strength of a light-cured resin cement contaminated with three different hemostatic solutions. Specimens were prepared for the control (uncontaminated resin cement) and experimental groups (resin cement contaminated with one of the hemostatic solutions) according to the tests. For degree of conversion, DC (n = 5) and color analyses (n = 10), specimens (3 mm in diameter and 2 mm thick) were evaluated by Fourier transform infrared spectroscopy (FTIR) and CIELAB spectrophotometry (L*, a*, b*), respectively. For elemental chemical analysis (n = 1), specimens (2 mm thick and 6 mm in diameter) were evaluated by x-ray energy-dispersive spectroscopy (EDS). The bond strengths of the groups were assessed by the microshear test (n = 20) in a leucite-reinforced glass ceramic substrate, followed by failure mode analysis by scanning electron microscopy (SEM). The mean values, except for the elemental chemical evaluation and failure mode, were evaluated by ANOVA and Tukey's HSD test. The color stability was influenced by storage time (p<0.001) and interaction between contamination and storage time (p<0.001). Hemostop and Viscostat Clear contamination did not affect the DC, however Viscostat increased the DC. Bond strength of the resin cement to ceramic was negatively affected by the contaminants (p<0.001). Contamination by hemostatic agents affected the bond strength, degree of conversion, and color stability of the light-cured resin cement tested.
Layer-by-Layer Enabled Nanomaterials for Chemical Sensing and Energy Conversion
NASA Astrophysics Data System (ADS)
Paterno, Leonardo G.; Soler, Maria A. G.
2013-06-01
The layer-by-layer (LbL) technique is a wet chemical method for the assembly of ultrathin films, with thicknesses up to 100 nm. This method is based on the successive transfer of molecular layers to a solid substrate that is dipped into cationic and anionic solutions in an alternating fashion. The adsorption is mainly driven by electrostatic interactions so that many molecular and nanomaterial systems can be engineered under this method. Moreover, it is inexpensive, can be easily performed, and does not demand sophisticated equipment or clean rooms. The most explored use of the LbL technique is to build up molecular devices for chemical sensing and energy conversion. Both applications require ultrathin films where specific elements must be organized with high control of thickness and spatial distribution, preferably in the nanolength and mesolength scales. In chemical sensors, the LbL technique is employed to assemble specific sensoactive materials such as conjugated polymers, enzymes, and immunological elements onto appropriated electrodes. Molecular recognition events are thus transduced by the assembled sensoactive layer. In energy-conversion devices, the LbL technique can be employed to fabricate different device's parts including electrodes, active layers, and auxiliary layers. In both applications, the devices' performance can be fully modulated and improved by simply varying film thickness and molecular architecture. The present review article highlights the main features of the LbL technique and provides a brief description of different (bio)chemical sensors, solar cells, and organic light-emitting diodes enabled by the LbL approach.
Tavano, Alessandro; Pesarin, Anna; Murino, Vittorio; Cristani, Marco
2014-01-01
Individuals with Asperger syndrome/High Functioning Autism fail to spontaneously attribute mental states to the self and others, a life-long phenotypic characteristic known as mindblindness. We hypothesized that mindblindness would affect the dynamics of conversational interaction. Using generative models, in particular Gaussian mixture models and observed influence models, conversations were coded as interacting Markov processes, operating on novel speech/silence patterns, termed Steady Conversational Periods (SCPs). SCPs assume that whenever an agent's process changes state (e.g., from silence to speech), it causes a general transition of the entire conversational process, forcing inter-actant synchronization. SCPs fed into observed influence models, which captured the conversational dynamics of children and adolescents with Asperger syndrome/High Functioning Autism, and age-matched typically developing participants. Analyzing the parameters of the models by means of discriminative classifiers, the dialogs of patients were successfully distinguished from those of control participants. We conclude that meaning-free speech/silence sequences, reflecting inter-actant synchronization, at least partially encode typical and atypical conversational dynamics. This suggests a direct influence of theory of mind abilities onto basic speech initiative behavior. PMID:24489674
Determination of double bond conversion in dental resins by near infrared spectroscopy.
Stansbury, J W; Dickens, S H
2001-01-01
This study determined the validity and practicality of near infrared (NIR) spectroscopic techniques for measurement of conversion in dental resins. Conversion measurements by NIR and mid-IR were compared using two techniques: (1) The conversion of 3mm thick photopolymerized Bis-GMA/TEGDMA resin specimens was determined by transmission NIR. Specimens were then ground and reanalyzed in KBr pellet form by mid-IR. (2) As further verification, thin resin films were photocured and analyzed by mid-IR. Multiple thin films were then compressed into a thick pellet for examination by NIR. Conversion values obtained by NIR and mid-IR techniques did not differ significantly. A correction for changing specimen thickness due to polymerization shrinkage was applied to NIR conversion measurements since an internal standard reference peak was not employed. Sensitivity of the NIR technique was superior to those based on the mid-IR. The nondestructive analysis of conversion in dental resins by NIR offers advantages of convenience, practical specimen dimensions and precision compared with standard mid-IR analytical procedures. Because glass is virtually transparent in the NIR spectrum, this technique has excellent potential for use with filled dental resins as well.
Massively parallel information processing systems for space applications
NASA Technical Reports Server (NTRS)
Schaefer, D. H.
1979-01-01
NASA is developing massively parallel systems for ultra high speed processing of digital image data collected by satellite borne instrumentation. Such systems contain thousands of processing elements. Work is underway on the design and fabrication of the 'Massively Parallel Processor', a ground computer containing 16,384 processing elements arranged in a 128 x 128 array. This computer uses existing technology. Advanced work includes the development of semiconductor chips containing thousands of feedthrough paths. Massively parallel image analog to digital conversion technology is also being developed. The goal is to provide compact computers suitable for real-time onboard processing of images.
Automatic Generation of Supervisory Control System Software Using Graph Composition
NASA Astrophysics Data System (ADS)
Nakata, Hideo; Sano, Tatsuro; Kojima, Taizo; Seo, Kazuo; Uchida, Tomoyuki; Nakamura, Yasuaki
This paper describes the automatic generation of system descriptions for SCADA (Supervisory Control And Data Acquisition) systems. The proposed method produces various types of data and programs for SCADA systems from equipment definitions using conversion rules. At first, this method makes directed graphs, which represent connections between the equipment, from equipment definitions. System descriptions are generated using the conversion rules, by analyzing these directed graphs, and finding the groups of equipment that involve similar operations. This method can make the conversion rules multi levels by using the composition of graphs, and can reduce the number of rules. The developer can define and manage these rules efficiently.
Cogeneration technology alternatives study. Volume 6: Computer data
NASA Technical Reports Server (NTRS)
1980-01-01
The potential technical capabilities of energy conversion systems in the 1985 - 2000 time period were defined with emphasis on systems using coal, coal-derived fuels or alternate fuels. Industrial process data developed for the large energy consuming industries serve as a framework for the cogeneration applications. Ground rules for the study were established and other necessary equipment (balance-of-plant) was defined. This combination of technical information, energy conversion system data ground rules, industrial process information and balance-of-plant characteristics was analyzed to evaluate energy consumption, capital and operating costs and emissions. Data in the form of computer printouts developed for 3000 energy conversion system-industrial process combinations are presented.
Reformulation of the relativistic conversion between coordinate time and atomic time
NASA Technical Reports Server (NTRS)
Thomas, J. B.
1975-01-01
The relativistic conversion between coordinate time and atomic time is reformulated to allow simpler time calculations relating analysis in solar system barycentric coordinates (using coordinate time) with earth-fixed observations (measuring 'earth-bound' proper time or atomic time). After an interpretation in terms of relatively well-known concepts, this simplified formulation, which has a rate accuracy of about 10 to the minus 15th, is used to explain the conventions required in the synchronization of a worldwide clock network and to analyze two synchronization techniques - portable clocks and radio interferometry. Finally, pertinent experimental tests of relativity are briefly discussed in terms of the reformulated time conversion.
Dynamic full-scalability conversion in scalable video coding
NASA Astrophysics Data System (ADS)
Lee, Dong Su; Bae, Tae Meon; Thang, Truong Cong; Ro, Yong Man
2007-02-01
For outstanding coding efficiency with scalability functions, SVC (Scalable Video Coding) is being standardized. SVC can support spatial, temporal and SNR scalability and these scalabilities are useful to provide a smooth video streaming service even in a time varying network such as a mobile environment. But current SVC is insufficient to support dynamic video conversion with scalability, thereby the adaptation of bitrate to meet a fluctuating network condition is limited. In this paper, we propose dynamic full-scalability conversion methods for QoS adaptive video streaming in SVC. To accomplish full scalability dynamic conversion, we develop corresponding bitstream extraction, encoding and decoding schemes. At the encoder, we insert the IDR NAL periodically to solve the problems of spatial scalability conversion. At the extractor, we analyze the SVC bitstream to get the information which enable dynamic extraction. Real time extraction is achieved by using this information. Finally, we develop the decoder so that it can manage the changing scalability. Experimental results showed that dynamic full-scalability conversion was verified and it was necessary for time varying network condition.
NASA Astrophysics Data System (ADS)
Nilsson, E. J. C.; Pallon, J.; Przybylowicz, W. J.; Wang, Y. D.; Jönsson, K. I.
2014-08-01
Although heavy on labor and equipment, thus not often applied, cryoanalysis of frozen hydrated biological specimens can provide information that better reflects the living state of the organism, compared with analysis in the freeze-dried state. In this paper we report a study where the cryoanalysis facility with cryosectioning capabilities at Materials Research Department, iThemba LABS, South Africa was employed to evaluate the usefulness of combining three ion beam analytical methods (μPIXE, RBS and STIM) to analyze a biological target where a better elemental compositional description is needed - the tardigrade. Imaging as well as quantification results are of interest. In a previous study, the element composition and redistribution of elements in the desiccated and active states of two tardigrade species was investigated. This study included analysis of both whole and sectioned tardigrades, and the aim was to analyze each specimen twice; first frozen hydrated and later freeze-dried. The combination of the three analytical techniques proved useful: elements from C to Rb in the tardigrades could be determined and certain differences in distribution of elements between the frozen hydrated and the freeze-dried states were observed. RBS on frozen hydrated specimens provided knowledge of matrix elements.
Top-down influences on visual attention during listening are modulated by observer sex.
Shen, John; Itti, Laurent
2012-07-15
In conversation, women have a small advantage in decoding non-verbal communication compared to men. In light of these findings, we sought to determine whether sex differences also existed in visual attention during a related listening task, and if so, if the differences existed among attention to high-level aspects of the scene or to conspicuous visual features. Using eye-tracking and computational techniques, we present direct evidence that men and women orient attention differently during conversational listening. We tracked the eyes of 15 men and 19 women who watched and listened to 84 clips featuring 12 different speakers in various outdoor settings. At the fixation following each saccadic eye movement, we analyzed the type of object that was fixated. Men gazed more often at the mouth and women at the eyes of the speaker. Women more often exhibited "distracted" saccades directed away from the speaker and towards a background scene element. Examining the multi-scale center-surround variation in low-level visual features (static: color, intensity, orientation, and dynamic: motion energy), we found that men consistently selected regions which expressed more variation in dynamic features, which can be attributed to a male preference for motion and a female preference for areas that may contain nonverbal information about the speaker. In sum, significant differences were observed, which we speculate arise from different integration strategies of visual cues in selecting the final target of attention. Our findings have implications for studies of sex in nonverbal communication, as well as for more predictive models of visual attention. Published by Elsevier Ltd.
Cantrell, Keri B; Stone, Kenneth C; Hunt, Patrick G; Ro, Kyoung S; Vanotti, Matias B; Burns, Joseph C
2009-07-01
Coastal bermudagrass (Cynodon dactylon L.) may be a potentially important source of bio-based energy in the southern US due to its vast acreage. It is often produced as part of a waste management plan with varying nutrient composition and energy characteristics on fields irrigated with livestock wastewater. The objective of this study was to determine the effect of subsurface drip irrigation with treated swine wastewater on both the quantity and quality of bermudagrass bioenergy. The treated wastewater was recycled from an advanced treatment system and used for irrigation of bermudagrass in two crop seasons. The experiment had nine water and drip line spacing treatments arrayed in a randomized complete block-design with four replicates. The bermudagrass was analyzed for calorific and mineral contents. Bermudagrass energy yields for 2004 and 2005 ranged from 127.4 to 251.4MJ ha(-1). Compared to irrigation with commercial nitrogen fertilizer, the least biomass energy density was associated with bermudagrass receiving treated swine wastewater. Yet, in 2004 the wastewater irrigated bermudagrass had greater hay yields leading to greater energy yield per ha. This decrease in energy density of wastewater irrigated bermudagrass was associated with increased concentrations of K, Ca, and Na. After thermal conversion, these compounds are known to remain in the ash portion thereby decreasing the energy density. Nonetheless, the loss of energy density using treated effluent via SDI may be offset by the positive influence of these three elements for their catalytic properties in downstream thermal conversion processes such as promoting a lesser char yield and greater combustible gas formation.
Ciesielski, Peter N.; Crowley, Michael F.; Nimlos, Mark R.; ...
2014-12-09
Biomass exhibits a complex microstructure of directional pores that impact how heat and mass are transferred within biomass particles during conversion processes. However, models of biomass particles used in simulations of conversion processes typically employ oversimplified geometries such as spheres and cylinders and neglect intraparticle microstructure. In this study, we develop 3D models of biomass particles with size, morphology, and microstructure based on parameters obtained from quantitative image analysis. We obtain measurements of particle size and morphology by analyzing large ensembles of particles that result from typical size reduction methods, and we delineate several representative size classes. Microstructural parameters, includingmore » cell wall thickness and cell lumen dimensions, are measured directly from micrographs of sectioned biomass. A general constructive solid geometry algorithm is presented that produces models of biomass particles based on these measurements. Next, we employ the parameters obtained from image analysis to construct models of three different particle size classes from two different feedstocks representing a hardwood poplar species ( Populus tremuloides, quaking aspen) and a softwood pine ( Pinus taeda, loblolly pine). Finally, we demonstrate the utility of the models and the effects explicit microstructure by performing finite-element simulations of intraparticle heat and mass transfer, and the results are compared to similar simulations using traditional simplified geometries. In conclusion, we show how the behavior of particle models with more realistic morphology and explicit microstructure departs from that of spherical models in simulations of transport phenomena and that species-dependent differences in microstructure impact simulation results in some cases.« less
Chromatographic-ICPMS methods for trace element and isotope analysis of water and biogenic calcite
NASA Astrophysics Data System (ADS)
Klinkhammer, G. P.; Haley, B. A.; McManus, J.; Palmer, M. R.
2003-04-01
ICP-MS is a powerful technique because of its sensitivity and speed of analysis. This is especially true for refractory elements that are notoriously difficult using TIMS and less energetic techniques. However, as ICP-MS instruments become more sensitive to elements of interest they also become more sensitive to interference. This becomes a pressing issue when analyzing samples with high total dissolved solids. This paper describes two trace element methods that overcome these problems by using chromatographic techniques to precondition samples prior to analysis by ICP-MS: separation of rare earth elements (REEs) from seawater using HPLC-ICPMS, and flow-through dissolution of foraminiferal calcite. Using HPLC in combination with ICP-MS it is possible to isolate the REEs from matrix, other transition elements, and each other. This method has been developed for small volume samples (5ml) making it possible to analyze sediment pore waters. As another example, subjecting foram shells to flow-through reagent addition followed by time-resolved analysis in the ICP-MS allows for systematic cleaning and dissolution of foram shells. This method provides information about the relationship between dissolution tendency and elemental composition. Flow-through is also amenable to automation thus yielding the high sample throughput required for paleoceanography, and produces a highly resolved elemental matrix that can be statistically analyzed.
Imai, Kazuhiro
2015-01-01
Finite element analysis (FEA) is an advanced computer technique of structural stress analysis developed in engineering mechanics. Because the compressive behavior of vertebral bone shows nonlinear behavior, a nonlinear FEA should be utilized to analyze the clinical vertebral fracture. In this article, a computed tomography-based nonlinear FEA (CT/FEA) to analyze the vertebral bone strength, fracture pattern, and fracture location is introduced. The accuracy of the CT/FEA was validated by performing experimental mechanical testing with human cadaveric specimens. Vertebral bone strength and the minimum principal strain at the vertebral surface were accurately analyzed using the CT/FEA. The experimental fracture pattern and fracture location were also accurately simulated. Optimization of the element size was performed by assessing the accuracy of the CT/FEA, and the optimum element size was assumed to be 2 mm. It is expected that the CT/FEA will be valuable in analyzing vertebral fracture risk and assessing therapeutic effects on osteoporosis. PMID:26029476
DOE Office of Scientific and Technical Information (OSTI.GOV)
Greitzer, Frank L.; Podmore, Robin
2008-11-17
The focus of the present study is on improved training approaches to accelerate learning and improved methods for analyzing effectiveness of tools within a high-fidelity power grid simulated environment. A theory-based model has been developed to document and understand the mental processes that an expert power system operator uses when making critical decisions. The theoretical foundation for the method is based on the concepts of situation awareness, the methods of cognitive task analysis, and the naturalistic decision making (NDM) approach of Recognition Primed Decision Making. The method has been systematically explored and refined as part of a capability demonstration ofmore » a high-fidelity real-time power system simulator under normal and emergency conditions. To examine NDM processes, we analyzed transcripts of operator-to-operator conversations during the simulated scenario to reveal and assess NDM-based performance criteria. The results of the analysis indicate that the proposed framework can be used constructively to map or assess the Situation Awareness Level of the operators at each point in the scenario. We can also identify the mental models and mental simulations that the operators employ at different points in the scenario. This report documents the method, describes elements of the model, and provides appendices that document the simulation scenario and the associated mental models used by operators in the scenario.« less
Realpe, Alba; Adams, Ann; Wall, Peter; Griffin, Damian; Donovan, Jenny L
2016-08-01
How a randomized controlled trial (RCT) is explained to patients is a key determinant of recruitment to that trial. This study developed and implemented a simple six-step model to fully inform patients and to support them in deciding whether to take part or not. Ninety-two consultations with 60 new patients were recorded and analyzed during a pilot RCT comparing surgical and nonsurgical interventions for hip impingement. Recordings were analyzed using techniques of thematic analysis and focused conversation analysis. Early findings supported the development of a simple six-step model to provide a framework for good recruitment practice. Model steps are as follows: (1) explain the condition, (2) reassure patients about receiving treatment, (3) establish uncertainty, (4) explain the study purpose, (5) give a balanced view of treatments, and (6) Explain study procedures. There are also two elements throughout the consultation: (1) responding to patients' concerns and (2) showing confidence. The pilot study was successful, with 70% (n = 60) of patients approached across nine centers agreeing to take part in the RCT, so that the full-scale trial was funded. The six-step model provides a promising framework for successful recruitment to RCTs. Further testing of the model is now required. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.
An Integrated Imaging Detector of Polarization and Spectral Content
NASA Technical Reports Server (NTRS)
Rust, D. M.; Thompson, K. E.
1993-01-01
A new type of image detector has been designed to simultaneously analyze the polarization of light at all picture elements in a scene. The Integrated Dual Imaging Detector (IDID) consists of a polarizing beamsplitter bonded to a charge-coupled device (CCD), with signal-analysis circuitry and analog-to-digital converters, all integrated on a silicon chip. It should be capable of 1:10(exp 4) polarization discrimination. The IDID should simplify the design and operation of imaging polarimeters and spectroscopic imagers used, for example, in atmospheric and solar research. Innovations in the IDID include (1) two interleaved 512 x 1024-pixel imaging arrays (one for each polarization plane); (2) large dynamic range (well depth of 10(exp 6) electrons per pixel); (3) simultaneous readout of both images at 10 million pixels per second each; (4) on-chip analog signal processing to produce polarization maps in real time; (5) on-chip 10-bit A/D conversion. When used with a lithium-niobate Fabry-Perot etalon or other color filter that can encode spectral information as polarization, the IDID can collect and analyze simultaneous images at two wavelengths. Precise photometric analysis of molecular or atomic concentrations in the atmosphere is one suggested application. When used in a solar telescope, the IDID will charge the polarization, which can then be converted to maps of the vector magnetic fields on the solar surface.
Would You Tell Everyone This? Facebook Conversations as Health Promotion Interventions
Syred, Jonathan; Naidoo, Carla; Woodhall, Sarah C
2014-01-01
Background Health promotion interventions on social networking sites can communicate individually tailored content to a large audience. User-generated content helps to maximize engagement, but health promotion websites have had variable success in supporting user engagement. Objective The aim of our study was to examine which elements of moderator and participant behavior stimulated and maintained interaction with a sexual health promotion site on Facebook. Methods We examined the pattern and content of posts on a Facebook page. Google analytics was used to describe the number of people using the page and viewing patterns. A qualitative, thematic approach was used to analyze content. Results During the study period (January 18, 2010, to June 27, 2010), 576 users interacted 888 times with the site through 508 posts and 380 comments with 93% of content generated by users. The user-generated conversation continued while new participants were driven to the site by advertising, but interaction with the site ceased rapidly after the advertising stopped. Conversations covered key issues on chlamydia and chlamydia testing. Users endorsed testing, celebrated their negative results, and modified and questioned key messages. There was variation in user approach to the site from sharing of personal experience and requesting help to joking about sexually transmitted infection. The moderator voice was reactive, unengaged, tolerant, simplistic, and was professional in tone. There was no change in the moderator approach throughout the period studied. Conclusions Our findings suggest this health promotion site provided a space for single user posts but not a self-sustaining conversation. Possible explanations for this include little new content from the moderator, a definition of content too narrow to hold the interest of participants, and limited responsiveness to user needs. Implications for health promotion practice include the need to consider a life cycle approach to online community development for health promotion and the need for a developing moderator strategy to reflect this. This strategy should reflect two facets of moderation for online health promotion interventions: (1) unengaged and professional oversight to provide a safe space for discussion and to maintain information quality, and (2) a more engaged and interactive presence designed to maintain interest that generates new material for discussion and is responsive to user requests. PMID:24727742
Evaluation of a microwave high-power reception-conversion array for wireless power transmission
NASA Technical Reports Server (NTRS)
Dickinson, R. M.
1975-01-01
Initial performance tests of a 24-sq m area array of rectenna elements are presented. The array is used as the receiving portion of a wireless microwave power transmission engineering verification test system. The transmitting antenna was located at a range of 1.54 km. Output dc voltage and power, input RF power, efficiency, and operating temperatures were obtained for a variety of dc load and RF incident power levels at 2388 MHz. Incident peak RF intensities of up to 170 mW/sq cm yielded up to 30.4 kW of dc output power. The highest derived collection-conversion efficiency of the array was greater than 80 percent.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Curchod, Basile F. E.; Martínez, Todd J., E-mail: toddjmartinez@gmail.com; SLAC National Accelerator Laboratory, Menlo Park, California 94025
2016-03-14
Full multiple spawning is a formally exact method to describe the excited-state dynamics of molecular systems beyond the Born-Oppenheimer approximation. However, it has been limited until now to the description of radiationless transitions taking place between electronic states with the same spin multiplicity. This Communication presents a generalization of the full and ab initio multiple spawning methods to both internal conversion (mediated by nonadiabatic coupling terms) and intersystem crossing events (triggered by spin-orbit coupling matrix elements) based on a spin-diabatic representation. The results of two numerical applications, a model system and the deactivation of thioformaldehyde, validate the presented formalism andmore » its implementation.« less
Shared Decision Making: The Need For Patient-Clinician Conversation, Not Just Information.
Hargraves, Ian; LeBlanc, Annie; Shah, Nilay D; Montori, Victor M
2016-04-01
The growth of shared decision making has been driven largely by the understanding that patients need information and choices regarding their health care. But while these are important elements for patients who make decisions in partnership with their clinicians, our experience suggests that they are not enough to address the larger issue: the need for the patient and clinician to jointly create a course of action that is best for the individual patient and his or her family. The larger need in evidence-informed shared decision making is for a patient-clinician interaction that offers conversation, not just information, and care, not just choice. Project HOPE—The People-to-People Health Foundation, Inc.
ERDA-NASA wind energy project ready to involve users
NASA Technical Reports Server (NTRS)
Thomas, R.; Puthoff, R.; Savino, J.; Johnson, W.
1976-01-01
The NASA contribution to the Wind Energy Project is discussed. NASA is responsible for the following: (1) identification of cost-effective configurations and sizes of wind-conversion systems, (2) the development of technology needed to produce these systems, (3) the design of wind-conversion systems that are compatible with user requirements, particularly utility networks, and (4) technology transfer obtained from the program to stimulate rapid commercial application of wind systems. Various elements of the NASA program are outlined, including industry-built user operation, the evaluation phase, the proposed plan and schedule for site selection and user involvement, supporting research and technology (e.g., energy storage), and component and subsystem technology development.
Thermoelectric energy conversion with solid electrolytes
NASA Astrophysics Data System (ADS)
Cole, T.
1983-09-01
The alkali metal thermoelectric converter (AMTEC) is a device for the direct conversion of heat to electrical energy. The sodium ion conductor beta-double prime-alumina is used to form a high-temperature regenerative concentration cell for elemental sodium. An AMTEC of mature design should have an efficiency of 20 to 40 percent, a power density of 0.5 kilowatt per kilogram or more, no moving parts, low maintenance requirements, high durability, and efficiency independent of size. It should be usable with high-temperature combustion, nuclear, or solar heat sources. Experiments have demonstrated the feasibility of the AMTEC and confirmed the theoretical analysis of the device. A wide range of applications from aerospace power to utility power plants appears possible.
Thermoelectric energy conversion with solid electrolytes.
Cole, T
1983-09-02
The alkali metal thermoelectric converter (AMTEC) is a device for the direct conversion of heat to electrical energy. The sodium ion conductor beta"- alumina is used to form a high-temperature regenerative concentration cell for elemental sodium. An AMTEC of mature design should have an efficiency of 20 to 40 percent, a power density of 0.5 kilowatt per kilogram or more, no moving parts, low maintenance requirements, high durability, and efficiency independent of size. It should be usable with high-temperature combustion, nuclear, or solar heat sources. Experiments have demonstrated the feasibility of the AMTEC and confirmed the theoretical analysis of the device. A wide range of applications from aerospace power to utility power plants appears possible.
Hosten, Bernard; Moreau, Ludovic; Castaings, Michel
2007-06-01
The paper presents a Fourier transform-based signal processing procedure for quantifying the reflection and transmission coefficients and mode conversion of guided waves diffracted by defects in plates made of viscoelastic materials. The case of the S(0) Lamb wave mode incident on a notch in a Perspex plate is considered. The procedure is applied to numerical data produced by a finite element code that simulates the propagation of attenuated guided modes and their diffraction by the notch, including mode conversion. Its validity and precision are checked by the way of the energy balance computation and by comparison with results obtained using an orthogonality relation-based processing method.
Curchod, Basile F. E.; Rauer, Clemens; Marquetand, Philipp; ...
2016-03-11
Full Multiple Spawning is a formally exact method to describe the excited-state dynamics of molecular systems beyond the Born-Oppenheimer approximation. However, it has been limited until now to the description of radiationless transitions taking place between electronic states with the same spin multiplicity. This Communication presents a generalization of the full and ab initio Multiple Spawning methods to both internal conversion (mediated by nonadiabatic coupling terms) and intersystem crossing events (triggered by spin-orbit coupling matrix elements) based on a spin-diabatic representation. Lastly, the results of two numerical applications, a model system and the deactivation of thioformaldehyde, validate the presented formalismmore » and its implementation.« less
NASA Technical Reports Server (NTRS)
Beratan, David N. (Inventor); Perry, Joseph W. (Inventor)
1991-01-01
A single material (not a multi-element structure) spatial light modulator may be written to, as well as read out from, using light. The device has tailorable rise and hold times dependent on the composition and concentration of the molecular species used as the active components. The spatial resolution of this device is limited only by light diffraction as in volume holograms. The device may function as a two-dimensional mask (transmission or reflection) or as a three-dimensional volume holographic medium. This device, based on optically-induced electron transfer, is able to perform incoherent to coherent image conversion or wavelength conversion over a wide spectral range (ultraviolet, visible, or near-infrared regions).
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yazawa, Kazuaki; Shakouri, Ali
The energy conversion efficiency of today’s thermoelectric generators is significantly lower than that of conventional mechanical engines. Almost all of the existing research is focused on materials to improve the conversion efficiency. Here we propose a general framework to study the cost-efficiency trade-off for thermoelectric power generation. A key factor is the optimization of thermoelectric modules together with their heat source and heat sinks. Full electrical and thermal co-optimization yield a simple analytical expression for optimum design. Based on this model, power output per unit mass can be maximized. We show that the fractional area coverage of thermoelectric elements inmore » a module could play a significant role in reducing the cost of power generation systems.« less
Battery voltage-balancing applications of disk-type radial mode Pb(Zr • Ti)O3 ceramic resonator
NASA Astrophysics Data System (ADS)
Thenathayalan, Daniel; Lee, Chun-gu; Park, Joung-hu
2017-10-01
In this paper, we propose a novel technique to build a charge-balancing circuit for series-connected battery strings using various kinds of disk-type ceramic Pb(Zr • Ti)O3 piezoelectric resonators (PRs). The use of PRs replaces the whole external battery voltage-balancer circuit, which consists mainly of a bulky magnetic element. The proposed technique is validated using different ceramic PRs and the results are analyzed in terms of their physical properties. A series-connected battery string with a voltage rating of 61.5 V is set as a hardware prototype under test, then the power transfer efficiency of the system is measured at different imbalance voltages. The performance of the proposed battery voltage-balancer circuit employed with a PR is also validated through hardware implementation. Furthermore, the temperature distribution image of the PR is obtained to compare power transfer efficiency and thermal stress under different operating conditions. The test results show that the battery voltage-balancer circuit can be successfully implemented using PRs with the maximum power conversion efficiency of over 96% for energy storage systems.
Jiang, Peng-Hui; Zhao, Rui-Feng; Zhao, Hai-Li; Lu, Li-Peng; Xie, Zuo-Lun
2013-06-01
Based on the 1975-2010 multi-temporal remotely sensed TM and ETM images and meteorological data, in combining with wavelet analysis, trend surface simulation, and interpolation method, this paper analyzed the meteorological elements' spatial distribution and change characteristics in the middle reaches of Heihe River, and elucidated the process of wetland landscape fragmentation in the study area by using the landscape indices patch density (PD), mean patch size (MPS), and patch shape fragment index (FS). The relationships between the wetland landscape fragmentation and climate change were also approached through correlation analysis and multiple stepwise regression analysis. In 1975-2010, the overall distribution patterns of precipitation and temperature in the study area were low precipitation in high temperature regions and high precipitation in low temperature regions, and the main characteristics of climate change were the conversion from dry to wet and from cold to warm. In the whole study period, the wetland landscape fragmentation was mainly manifested in the decrease of MPS, with a decrement of 48.95 hm2, and the increase of PD, with an increment of 0.006 ind x hm(-2).
Li, Tuoyu; Ma, Zongwen; Xu, Xuegong
2017-01-01
The article examines the detailed spatial and temporal distributions of coastal reclamation in the northwest coast of Bohai Bay experiencing rapid coastal reclamation in China from 1974 to 2010 in annual intervals. Moreover, soil elements properties and spatial distribution in reclaimed area and inform the future coastal ecosystems management was also analyzed. The results shows that 910.7 km2 of coastal wetlands have been reclaimed and conversed to industrial land during the past 36 years. It covers intertidal beach, shallow sea and island with a percentage of 76.0%, 23.5% and 0.5%, respectively. The average concentration of Mn is 686.91mg/kg and the order of concentration of heavy metal are Cr>Zn>As>Ni>Cu>Pb>Cd>Hg. We used the "space for time substitution" method to test the soil properties changes after reclamation. The potential ecological risk of heavy metal is in low level and the risk of Cd and As is relatively higher. The ecosystem-based coastal protection and management are urgent to support sustainable coastal ecosystems in Bohai bay in the future. PMID:28422982
First-Principles Investigations of Lead-Free Formamidinium Based Hybrid Perovskites
NASA Astrophysics Data System (ADS)
Murat, Altynbek; Schwingenschlögl, Udo
2015-03-01
Hybrid organic-inorganic perovskite solar cells have recently emerged as the next-generation photovoltaic technology. Most of the research work has been focused on the prototype MAPbI3 perovskite (MA = Methylammonium = CH3NH3+) and its analogues that have lead to power conversion efficiencies in excess of 15%. Despite the huge success, these materials are still non-optimal in terms of optical absorption where the bandgaps are greater than 1.6 eV as well as the toxicology issue of lead. Thus, investigation and development of lead-free perovskites with bandgaps closer to optimal, allowing greater spectral absorption, is of great interest. In this work, we perform first principles calculations to study the structural, optical, and electronic properties of new derivatives of MAPbI3 in which the organic MA cation is replaced by other organic amines of similar size such as Formamidinium (FA) and/or the Pb cation replaced by similar elements such as Sn. In particular, we investigate the role and effect of FA and Pb cations on the electronic and optical properties and analyze to which extend the bandgaps can be tuned.
Zhu, Gaoru; Xie, Zhenglei; Li, Tuoyu; Ma, Zongwen; Xu, Xuegong
2017-01-01
The article examines the detailed spatial and temporal distributions of coastal reclamation in the northwest coast of Bohai Bay experiencing rapid coastal reclamation in China from 1974 to 2010 in annual intervals. Moreover, soil elements properties and spatial distribution in reclaimed area and inform the future coastal ecosystems management was also analyzed. The results shows that 910.7 km2 of coastal wetlands have been reclaimed and conversed to industrial land during the past 36 years. It covers intertidal beach, shallow sea and island with a percentage of 76.0%, 23.5% and 0.5%, respectively. The average concentration of Mn is 686.91mg/kg and the order of concentration of heavy metal are Cr>Zn>As>Ni>Cu>Pb>Cd>Hg. We used the "space for time substitution" method to test the soil properties changes after reclamation. The potential ecological risk of heavy metal is in low level and the risk of Cd and As is relatively higher. The ecosystem-based coastal protection and management are urgent to support sustainable coastal ecosystems in Bohai bay in the future.
Collins, Michael; Cawley, Adam T; Heagney, Aaron C; Kissane, Luke; Robertson, James; Salouros, Helen
2009-07-01
Conventional chemical profiling of methylamphetamine has been used for many years to determine the synthetic route employed and where possible to identify the precursor chemicals used. In this study stable isotope ratio analysis was investigated as a means of determining the origin of the methylamphetamine precursors, ephedrine and pseudoephedrine. Ephedrine and pseudoephedrine may be prepared industrially by several routes. Results are presented for the stable isotope ratios of carbon (delta(13)C), nitrogen (delta(15)N) and hydrogen (delta(2)H) measured in methylamphetamine samples synthesized from ephedrine and pseudoephedrine of known provenance. It is clear from the results that measurement of the delta(13)C, delta(15)N and delta(2)H stable isotope ratios by elemental analyzer/thermal conversion isotope ratio mass spectrometry (EA/TC-IRMS) in high-purity methylamphetamine samples will allow determination of the synthetic source of the ephedrine or pseudoephedrine precursor as being either of a natural, semi-synthetic, or fully synthetic origin. Copyright (c) 2009 Commonwealth of Australia.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yoon, Sarah; Jung, Jaesung; Kim, Taeyeung
In this study, HepG2-hepatitis B virus (HBV)-stable cells that did not overexpress HBx and HBx-deficient mutant-transfected cells were analyzed for their expression of HBV-induced, upregulated adipogenic and lipogenic genes. The mRNAs of CCAAT enhancer binding protein {alpha} (C/EBP{alpha}), peroxisome proliferator-activated receptor {gamma} (PPAR{gamma}), adiponectin, liver X receptor {alpha} (LXR{alpha}), sterol regulatory element binding protein 1c (SREBP1c), and fatty acid synthase (FAS) were expressed at higher levels in HepG2-HBV and lamivudine-treated stable cells and HBx-deficient mutant-transfected cells than in the HepG2 cells. Lamivudine treatment reduced the mRNA levels of PPAR{gamma} and C/EBP{alpha}. Conversely, HBV replication was upregulated by adiponectin and PPAR{gamma}more » agonist rosiglitazone treatments and was downregulated by adiponectin siRNAs. Collectively, our results demonstrate that HBV replication and/or protein expression, even in the absence of HBx, upregulated adipogenic or lipogenic genes, and that the control of adiponectin might prove useful as a therapeutic modality for the treatment of chronic hepatitis B.« less
[Genome-scale sequence data processing and epigenetic analysis of DNA methylation].
Wang, Ting-Zhang; Shan, Gao; Xu, Jian-Hong; Xue, Qing-Zhong
2013-06-01
A new approach recently developed for detecting cytosine DNA methylation (mC) and analyzing the genome-scale DNA methylation profiling, is called BS-Seq which is based on bisulfite conversion of genomic DNA combined with next-generation sequencing. The method can not only provide an insight into the difference of genome-scale DNA methylation among different organisms, but also reveal the conservation of DNA methylation in all contexts and nucleotide preference for different genomic regions, including genes, exons, and repetitive DNA sequences. It will be helpful to under-stand the epigenetic impacts of cytosine DNA methylation on the regulation of gene expression and maintaining silence of repetitive sequences, such as transposable elements. In this paper, we introduce the preprocessing steps of DNA methylation data, by which cytosine (C) and guanine (G) in the reference sequence are transferred to thymine (T) and adenine (A), and cytosine in reads is transferred to thymine, respectively. We also comprehensively review the main content of the DNA methylation analysis on the genomic scale: (1) the cytosine methylation under the context of different sequences; (2) the distribution of genomic methylcytosine; (3) DNA methylation context and the preference for the nucleotides; (4) DNA- protein interaction sites of DNA methylation; (5) degree of methylation of cytosine in the different structural elements of genes. DNA methylation analysis technique provides a powerful tool for the epigenome study in human and other species, and genes and environment interaction, and founds the theoretical basis for further development of disease diagnostics and therapeutics in human.
Performance analysis of hybrid vibrational energy harvesters with experimental verification
NASA Astrophysics Data System (ADS)
Sriramdas, Rammohan; Pratap, Rudra
2018-07-01
In the present work, performance indices for a hybrid energy harvester (HEH) that is composed of piezoelectric and electrodynamic or electromagnetic mechanisms of energy conversion are analyzed. Performance of a HEH is defined in terms of Q-normalized power factor and efficiency of conversion. They are observed to acutely depend on coupling strength or figures of merit in both piezoelectric and electrodynamic domains. The influence of figures of merit on the Q-normalized power factor, and the limits of conversion efficiency are explored. Based on the studies, a suitable range for figures of merit that would maximize both Q-normalized power factor and conversion efficiency in hybrid harvesters is proposed. The proposed idea is verified experimentally for the appropriate values of figures of merit and efficiencies by fabricating and testing four experimental models of the HEHs.
Study on film resistivity of Energy Conversion Components for MEMS Initiating Explosive Device
NASA Astrophysics Data System (ADS)
Ren, Wei; Zhang, Bin; Zhao, Yulong; Chu, Enyi; Yin, Ming; Li, Hui; Wang, Kexuan
2018-03-01
Resistivity of Plane-film Energy Conversion Components is a key parameter to influence its resistance and explosive performance, and also it has important relations with the preparation of thin film technology, scale, structure and etc. In order to improve the design of Energy Conversion Components for MEMS Initiating Explosive Device, and reduce the design deviation of Energy Conversion Components in microscale, guarantee the design resistance and ignition performance of MEMS Initiating Explosive Device, this paper theoretically analyzed the influence factors of film resistivity in microscale, through the preparation of Al film and Ni-Cr film at different thickness with micro/nano, then obtain the film resistivity parameter of the typical metal under different thickness, and reveals the effect rule of the scale to the resistivity in microscale, at the same time we obtain the corresponding inflection point data.
Narrative Voices of Early Adolescents: Influences of Learning Disability and Cultural Background
ERIC Educational Resources Information Center
Celinska, Dorota K.
2009-01-01
This study analyzed personal and fictional narratives of culturally/ethnically diverse students with and without learning disabilities. The participants were 82 fourth to seventh graders from urban and suburban schools located in a Midwest metropolitan area. Narratives were elicited in the context of naturalistic conversation and analyzed using…
ERIC Educational Resources Information Center
Ma, T. S.; Gutterson, Milton
1980-01-01
Reviews general developments in computerization and data processing of organic elemental analyses; carbon, hydrogen, and nitrogen analyzers; procedures for determining oxygen, sulfur, and halogens, as well as other nometallic elements and organometallics. Selected papers on trace analysis of nonmetals and determination of metallic elements are…
DOE Office of Scientific and Technical Information (OSTI.GOV)
None
2000-04-01
The NITON{reg_sign} 800 series analyzer is a hand-held, battery operated unit that measures 8-in x 3-in x 2-in and weighs 2.5 pounds. The analyzer uses x-ray fluorescence spectrum analysis to identify and quantify elements in metal and then compares the readings to a built-in library to determine a metal's alloy. The library contains 300 elements and alloys, and can be customized to identify other elements and alloys (depending on the sources in the instrument). The basic unit utilizes a Cadmium-109 source, but each analyzer unit can hold up to two sources. These sources include Iron-55 and Americium-241. Pushing a safetymore » button located on the side of the unit and placing it against a surface opens the shutter window. Within seconds the unit beeps, and displays the results. The analyzer stores up to 1,000 data sets, including sample identification codes using a barcode reader. The data is easily downloaded to a conventional computer when sampling has been completed. Batteries are good for 8-hrs and charge in less than 2 hours and it can be carried, shipped, or transported without exterior labeling, conforming to 49 CFR 143.421.« less
New Hydrokinetic Turbine for Free Surface Gravitational Wave Transformation
NASA Astrophysics Data System (ADS)
Berins, J.
2017-12-01
The present article deals with an alternative form of energy - the conversion of marine/ocean wave energy using an axial self-regulating blade (SB) hydrokinetic turbine (ASRBHK turbine). The article analyses the operation of the ASRBHK turbine and draws the resulting conclusions about the mechanism, in which the power transfer element is a self-regulating blade.
eCAF: A New Tool for the Conversational Analysis of Electronic Communication
ERIC Educational Resources Information Center
Duncan-Howell, Jennifer
2009-01-01
Electronic communication is characteristically concerned with "the message" (eM), those who send them (S), and those who receive and read them (R). This relationship could be simplified into the equation eM = S + R. When this simple equation is applied to electronic communication, several elements are added that make this straightforward act of…
Remote sensing application challenges in the Mekong region
Jeffrey Himel
2013-01-01
Forest degradation is not just one of the cornerstones of "REDD+", it is a critical element for Lao PDR and other countries where the primary driver of forest carbon loss is selective logging and small-scale conversion of forest for agriculture rather than deforestation. Unless we can reliably and accurately quantify the area of degradation using remote...
ERIC Educational Resources Information Center
Weissman, Kabeera M.
2012-01-01
This study focused on exploring and creating life pathways with a group of twelfth graders at West Philadelphia High School. I invited students to inquire into "life pathways," broadly construed; participants chose to concentrate on transitions to college. Although scholars have investigated many elements of college access, there is…
Language Acquisition among Adult Immigrants in Canada: The Effect of Premigration Language Capital
ERIC Educational Resources Information Center
Adamuti-Trache, Maria
2013-01-01
Gaining proficiency in the host country language is a key element to successful integration of new immigrants. In this article, the author adopts Bourdieu's perspective that accumulation and conversion of forms of capital is only possible through practice in a social field; therefore, the author puts forward the idea that language capital…
The Roles of Extrinsic Factors in a Community of Inquiry Model of E-Learning
ERIC Educational Resources Information Center
Lee, Richard; Faulkner, Margaret
2011-01-01
Despite its proliferation in higher learning institutions, e-learning has been criticised as being nothing more than trivial online conversations, or a mere means of delivering class materials electronically. If e-learning is to address such criticisms and become an effective pedagogical platform, educators need to identify elements critical to…
The Influences of the 2D Image-Based Augmented Reality and Virtual Reality on Student Learning
ERIC Educational Resources Information Center
Liou, Hsin-Hun; Yang, Stephen J. H.; Chen, Sherry Y.; Tarng, Wernhuar
2017-01-01
Virtual reality (VR) learning environments can provide students with concepts of the simulated phenomena, but users are not allowed to interact with real elements. Conversely, augmented reality (AR) learning environments blend real-world environments so AR could enhance the effects of computer simulation and promote students' realistic experience.…
Relationships between Sitka black-tailed deer and their habitat.
Thomas A. Hanley
1984-01-01
Old-growth, western hemlock-Sitka spruce forest in southeastern Alaska is an important element of the habitat of Sitka black-tailed deer. The conversion of uneven-aged, old-growth forests to even-aged, second-growth forests has generated concern about the future carrying capacity of the habitat for deer, especially where snow accumulation is common on winter ranges....
Betavoltaic p--n+-structure simulation
NASA Astrophysics Data System (ADS)
Urchuk, S. U.; Murashev, V. N.; Legotin, S. A.; Krasnov, A. A.; Rabinovich, O. I.; Kuzmina, K. A.; Omel'chenko, Y. K.; Osipov, U. V.; Didenko, S. I.
2016-08-01
In order to increase the betavoltaic batteries efficiency output characteristics of the p--n+ (n--p+) - structures were simulated. Replacing the p+-n-structures on the p-n+ and n-p+ -structures enables the space-charge expansion to the crystal surface and thus to reduce the recombination loss in the heavy doped p+-layer and improve conversion of betavoltaic elements efficiency.
ERIC Educational Resources Information Center
Williams, Kerry Curtiss; Veomett, George E.
2006-01-01
Teaching science means doing science and involves three elements: knowing content, knowing children, and teachers knowing themselves as teachers and learners. The authors describe principles and requirements that reflect National Science Education Standards for the active learning of science. They identify key ingredients for primary students and…
Log production in Washington and Oregon: an historical perspective.
Brian R. Wall
1972-01-01
In the history of the Pacific Northwest, log production and conversion have been major economic activities. The long-term trends in timber harvesting have been upward, and most of the harvest has come from large old-growth forest inventories. National and international demands for timber have been a major element in putting upward pressure on log production levels....
Methods and systems for micro transmissions
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stalford, Harold L
2014-12-23
Methods and systems for micro transmissions for a micro machine may comprise an input shaft assembly coupled to a micro actuator, an output shaft assembly coupled to a micro shaft, and one or more power conversion elements operable to convert a first type of movement from the micro actuator into a second, disparate type of movement for the micro shaft.
Dealing with Difficult Conversations: Anti-Racism in Youth & Community Work Training
ERIC Educational Resources Information Center
Watt, Diana
2017-01-01
This paper represents a critical reflection on youth and community work students' response to a module on race equality and diversity. An awareness of issues in relation to power and oppression are amongst the core elements of youth and community work training. Throughout their study, youth and community work students are engaged in conversations…
NASA Astrophysics Data System (ADS)
Tararykov, A. V.; Garyaev, A. B.
2017-11-01
The possibility of increasing the energy efficiency of production processes by converting the initial fuel - natural gas to synthesized fuel using the heat of the exhaust gases of plants involved in production is considered. Possible applications of this technology are given. A mathematical model of the processes of heat and mass transfer occurring in a thermochemical reactor is developed taking into account the nonequilibrium nature of the course of chemical reactions of fuel conversion. The possibility of using microchannel reaction elements and facilities for methane conversion in order to intensify the process and reduce the overall dimensions of plants is considered. The features of the course of heat and mass transfer processes under flow conditions in microchannel reaction elements are described. Additions have been made to the mathematical model, which makes it possible to use it for microchannel installations. With the help of a mathematical model, distribution of the parameters of mixtures along the length of the reaction element of the reactor-temperature, the concentration of the reacting components, the velocity, and the values of the heat fluxes are obtained. The calculations take into account the change in the thermophysical properties of the mix-ture, the type of the catalytic element, the rate of the reactions, the heat exchange processes by radiation, and the lon-gitudinal heat transfer along the flow of the reacting mixture. The reliability of the results of the application of the mathematical model is confirmed by their comparison with the experimental data obtained by Grasso G., Schaefer G., Schuurman Y., Mirodatos C., Kuznetsov V.V., Vitovsky O.V. on similar installations.
Roberts, David A; Paul, Nicholas A; Cole, Andrew J; de Nys, Rocky
2015-07-01
Macroalgae can be grown in industrial waste water to sequester metals and the resulting biomass used for biotechnological applications. We have previously cultivated the freshwater macroalga Oedogonium at a coal-fired power station to treat a metal-contaminated effluent from that facility. We then produced biochar from this biomass and determined the suitability of both the biomass and the biochar for soil amelioration. The dried biomass of Oedogonium cultivated in the waste water contained several elements for which there are terrestrial biosolids criteria (As, Cd, Cr, Cu, Pb, Ni, Se and Zn) and leached significant amounts of these elements into solution. Here, we demonstrate that these biomass leachates impair the germination and growth of radishes as a model crop. However, the biochar produced from this same biomass leaches negligible amounts of metal into solution and the leachates support high germination and growth of radishes. Biochar produced at 750 °C leaches the least metal and has the highest recalcitrant C content. When this biochar is added to a low-quality soil it improves the retention of nutrients (N, P, Ca, Mg, K and Mo) from fertilizer in the soil and the growth of radishes by 35-40%. Radishes grown in the soils amended with the biochar have equal or lower metal contents than radishes grown in soil without biochar, but much higher concentrations of essential trace elements (Mo) and macro nutrients (P, K, Ca and Mg). The cultivation of macroalgae is an effective waste water bioremediation technology that also produces biomass that can be used as a feedstock for conversion to biochar for soil amelioration. Copyright © 2015 Elsevier Ltd. All rights reserved.
Catalytic conversion of syngas to mixed alcohols over Zn-Mn promoted Cu-Fe based catalyst
Lu, Yongwu; Yu, Fei; Hu, Jin; ...
2012-04-12
Zn-Mn promoted Cu-Fe based catalyst was synthesized by the co-precipitation method. Mixed alcohols synthesis from syngas was studied in a half-inch tubular reactor system after the catalyst was reduced. Zn-Mn promoted Cu-Fe based catalyst was characterized by SEM-EDS, TEM, XRD, and XPS. The liquid phase products (alcohol phase and hydrocarbon phase) were analyzed by GC-MS and the gas phase products were analyzed by GC. The results showed that Zn-Mn promoted Cu-Fe based catalyst had high catalytic activity and high alcohol selectivity. The maximal CO conversion rate was 72%, and the yield of alcohol and hydrocarbons were also very high. Cumore » (111) was the active site for mixed alcohols synthesis, Fe 2C (101) was the active site for olefin and paraffin synthesis. The reaction mechanism of mixed alcohols synthesis from syngas over Zn-Mn promoted Cu-Fe based catalyst was proposed. Here, Zn-Mn promoted Cu-Fe based catalyst can be regarded as a potential candidate for catalytic conversion of biomass-derived syngas to mixed alcohols.« less
Zhang, Xiaoyu; Song, Chunxia; Yang, Ke; Hong, Wenwen; Lu, Ying; Yu, Ping; Mao, Lanqun
2018-04-17
Electrochemical aptasensors generally include three elements, that is, recognition element, signal-transformation element, and regeneration element. In this study, a new adenosine triphosphate (ATP) aptasensor is developed by combining three elements into one DNA oligonucleotide chain. In the DNA oligonucleotide chain, DNA aptamer is used as the recognition element, ferrocene group attached at the 3'-end of the aptamer is used as the signal-transformation element, and azobenzene moiety embedded into the DNA chain is used as the regeneration element. In addition to the similar analytical properties with the traditional ones, the aptasensor developed here is easily regenerated with UV-light irradiation. The current response recorded on the aptasensor increases with increasing the concentration of ATP in the incubation solution and is linear with the logarithm of ATP concentration in the range from 1 nM to 100 μM. The limit of detection is 0.5 nM (S/N = 3). The basal level of ATP in the rat brain cortex microdialysate is determined to be 21.33 ± 4.1 nM ( n = 3). After being challenged with ATP, the aptasensor could be readily regenerated by UV-light irradiation for more than seven cycles. The regeneration of the aptasensor is proposed to be regulated by conversing azobenzene from its trans to cis form under UV irradiation.
Yang, Nuoya; Medford, Andrew J.; Liu, Xinyan; ...
2016-01-31
Synthesis gas (CO + H 2) conversion is a promising route to converting coal, natural gas, or biomass into synthetic liquid fuels. Rhodium has long been studied as it is the only elemental catalyst that has demonstrated selectivity to ethanol and other C 2+ oxygenates. However, the fundamentals of syngas conversion over rhodium are still debated. In this work a microkinetic model is developed for conversion of CO and H 2 into methane, ethanol, and acetaldehyde on the Rh (211) and (111) surfaces, chosen to describe steps and close-packed facets on catalyst particles. The model is based on DFT calculationsmore » using the BEEF-vdW functional. The mean-field kinetic model includes lateral adsorbate–adsorbate interactions, and the BEEF-vdW error estimation ensemble is used to propagate error from the DFT calculations to the predicted rates. The model shows the Rh(211) surface to be ~6 orders of magnitude more active than the Rh(111) surface, but highly selective toward methane, while the Rh(111) surface is intrinsically selective toward acetaldehyde. A variety of Rh/SiO 2 catalysts are synthesized, tested for catalytic oxygenate production, and characterized using TEM. The experimental results indicate that the Rh(111) surface is intrinsically selective toward acetaldehyde, and a strong inverse correlation between catalytic activity and oxygenate selectivity is observed. Furthermore, iron impurities are shown to play a key role in modulating the selectivity of Rh/SiO 2 catalysts toward ethanol. The experimental observations are consistent with the structure-sensitivity predicted from theory. As a result, this work provides an improved atomic-scale understanding and new insight into the mechanism, active site, and intrinsic selectivity of syngas conversion over rhodium catalysts and may also guide rational design of alloy catalysts made from more abundant elements.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Nuoya; Medford, Andrew J.; Liu, Xinyan
Synthesis gas (CO + H 2) conversion is a promising route to converting coal, natural gas, or biomass into synthetic liquid fuels. Rhodium has long been studied as it is the only elemental catalyst that has demonstrated selectivity to ethanol and other C 2+ oxygenates. However, the fundamentals of syngas conversion over rhodium are still debated. In this work a microkinetic model is developed for conversion of CO and H 2 into methane, ethanol, and acetaldehyde on the Rh (211) and (111) surfaces, chosen to describe steps and close-packed facets on catalyst particles. The model is based on DFT calculationsmore » using the BEEF-vdW functional. The mean-field kinetic model includes lateral adsorbate–adsorbate interactions, and the BEEF-vdW error estimation ensemble is used to propagate error from the DFT calculations to the predicted rates. The model shows the Rh(211) surface to be ~6 orders of magnitude more active than the Rh(111) surface, but highly selective toward methane, while the Rh(111) surface is intrinsically selective toward acetaldehyde. A variety of Rh/SiO 2 catalysts are synthesized, tested for catalytic oxygenate production, and characterized using TEM. The experimental results indicate that the Rh(111) surface is intrinsically selective toward acetaldehyde, and a strong inverse correlation between catalytic activity and oxygenate selectivity is observed. Furthermore, iron impurities are shown to play a key role in modulating the selectivity of Rh/SiO 2 catalysts toward ethanol. The experimental observations are consistent with the structure-sensitivity predicted from theory. As a result, this work provides an improved atomic-scale understanding and new insight into the mechanism, active site, and intrinsic selectivity of syngas conversion over rhodium catalysts and may also guide rational design of alloy catalysts made from more abundant elements.« less
Keitel, Anne; Daum, Moritz M.
2015-01-01
The anticipation of a speaker’s next turn is a key element of successful conversation. This can be achieved using a multitude of cues. In natural conversation, the most important cue for adults to anticipate the end of a turn (and therefore the beginning of the next turn) is the semantic and syntactic content. In addition, prosodic cues, such as intonation, or visual signals that occur before a speaker starts speaking (e.g., opening the mouth) help to identify the beginning and the end of a speaker’s turn. Early in life, prosodic cues seem to be more important than in adulthood. For example, it was previously shown that 3-year-old children anticipated more turns in observed conversations when intonation was available compared with when not, and this beneficial effect was present neither in younger children nor in adults (Keitel et al., 2013). In the present study, we investigated this effect in greater detail. Videos of conversations between puppets with either normal or flattened intonation were presented to children (1-year-olds and 3-year-olds) and adults. The use of puppets allowed the control of visual signals: the verbal signals (speech) started exactly at the same time as the visual signals (mouth opening). With respect to the children, our findings replicate the results of the previous study: 3-year-olds anticipated more turns with normal intonation than with flattened intonation, whereas 1-year-olds did not show this effect. In contrast to our previous findings, the adults showed the same intonation effect as the 3-year-olds. This suggests that adults’ cue use varies depending on the characteristics of a conversation. Our results further support the notion that the cues used to anticipate conversational turns differ in development. PMID:25713548
Soto, Gloria; Clarke, Michael T
2017-07-12
This study was conducted to evaluate the effects of a conversation-based intervention on the expressive vocabulary and grammatical skills of children with severe motor speech disorders and expressive language delay who use augmentative and alternative communication. Eight children aged from 8 to 13 years participated in the study. After a baseline period, a conversation-based intervention was provided for each participant, in which they were supported to learn and use linguistic structures essential for the formation of clauses and the grammaticalization of their utterances, such as pronouns, verbs, and bound morphemes, in the context of personally meaningful and scaffolded conversations with trained clinicians. The conversations were videotaped, transcribed, and analyzed using the Systematic Analysis of Language Transcripts (SALT; Miller & Chapman, 1991). Results indicate that participants showed improvements in their use of spontaneous clauses, and a greater use of pronouns, verbs, and bound morphemes. These improvements were sustained and generalized to conversations with familiar partners. The results demonstrate the positive effects of the conversation-based intervention for improving the expressive vocabulary and grammatical skills of children with severe motor speech disorders and expressive language delay who use augmentative and alternative communication. Clinical and theoretical implications of conversation-based interventions are discussed and future research needs are identified. https://doi.org/10.23641/asha.5150113.
Conversational Entrainment of Vocal Fry in Young Adult Female American English Speakers.
Borrie, Stephanie A; Delfino, Christine R
2017-07-01
Conversational entrainment, the natural tendency for people to modify their behaviors to more closely match their communication partner, is examined as one possible mechanism modulating the prevalence of vocal fry in the speech of young American women engaged in spoken dialogue. Twenty young adult female American English speakers engaged in two spoken dialogue tasks-one with a young adult female American English conversational partner who exhibited substantial vocal fry and one with a young adult female American English conversational partner who exhibited quantifiably less vocal fry. Dialogues were analyzed for proportion of vocal fry, by speaker, and two measures of communicative success (efficiency and enjoyment). Participants employed significantly more vocal fry when conversing with the partner who exhibited substantial vocal fry than when conversing with the partner who exhibited quantifiably less vocal fry. Further, greater similarity between communication partners in their use of vocal fry tracked with higher scores of communicative efficiency and communicative enjoyment. Conversational entrainment offers a mechanistic framework that may be used to explain, to some degree, the frequency with which vocal fry is employed by young American women engaged in spoken dialogue. Further, young American women who modulated their vocal patterns during dialogue to match those of their conversational partner gained more efficiency and enjoyment from their interactions, demonstrating the cognitive and social benefits of entrainment. Copyright © 2017 The Voice Foundation. Published by Elsevier Inc. All rights reserved.