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1

Correction for Thermal EMFs in Thermocouple Feedthroughs  

NASA Technical Reports Server (NTRS)

A straightforward measurement technique provides for correction of thermal-electromotive-force (thermal-EMF) errors introduced by temperature gradients along the pins of non-thermocouple-alloy hermetic feedthrough connectors for thermocouple extension wires that must pass through bulkheads. This technique is an alternative to the traditional technique in which the thermal-EMF errors are eliminated by use of custom-made multipin hermetic feedthrough connectors that contain pins made of the same alloys as those of the thermocouple extension wires. One disadvantage of the traditional technique is that it is expensive and time-consuming to fabricate multipin custom thermocouple connectors. In addition, the thermocouple-alloy pins in these connectors tend to corrode easily and/or tend to be less rugged compared to the non-thermocouple-alloy pins of ordinary connectors. As the number of thermocouples (and thus pins) is increased in a given setup, the magnitude of these disadvantages increases accordingly. The present technique is implemented by means of a little additional hardware and software, the cost of which is more than offset by the savings incurred through the use of ordinary instead of thermocouple connectors. The figure schematically depicts a typical measurement setup to which the technique is applied. The additional hardware includes an isothermal block (made of copper) instrumented with a reference thermocouple and a compensation thermocouple. The reference thermocouple is connected to an external data-acquisition system (DAS) through a two-pin thermocouple-alloy hermetic feedthrough connector, but this is the only such connector in the apparatus. The compensation thermocouple is connected to the DAS through two pins of the same ordinary multipin connector that connects the measurement thermocouples to the DAS.

Ziemke, Robert A.

2006-01-01

2

A very low thermal EMF computer-controlled scanner  

NASA Astrophysics Data System (ADS)

A very low thermal electromotive force (EMF) scanner was designed in our laboratory five years ago. The device was developed to automatically calibrate up to 12 Zener-based voltage standards by comparison to a programmable Josephson voltage standard, but can be used in any set-up that requires automation to set electrical contacts with a repeatability of the thermal EMFs at the nanovolt level. This paper explains how this device achieves robustness of metrological characteristics even after several thousand connections since its first installation. One scanner position shows a voltage offset of 60 nV with a standard deviation of 7 nV while the remaining 11 show offset values between -15 nV and +25 nV with an associated Type A uncertainty varying from 2 to 7 nV. Herein, we present the results of a series of measurements on all channels. Sub-nanovolt residual thermal short EMF variations are demonstrated using Allan variance statistical analysis.

Chayramy, R.; Solve, S.

2013-02-01

3

Anomalous increase of the thermal emf in epitaxial graphene on size-quantized films  

NASA Astrophysics Data System (ADS)

The thermoelectric effect in epitaxial graphene formed on the surface of a size-quantized metal film is examined in the context of a Davydov model. An approach based on the Kubo formula for the conductivity and differential thermal emf is used. It is shown that because of size quantization, near the edges of the energy levels the thermal emf of epitaxial graphene increases to gigantic values of 200 ?V/K, or almost a factor of seven greater than the emf of isolated graphene (about 30 ?V/K).

Alisultanov, Z. Z.; Mirzegasanova, N. A.

2014-05-01

4

Absolute Thermal SST Measurements over the Deepwater Horizon Oil Spill  

NASA Astrophysics Data System (ADS)

Climate monitoring and natural disaster rapid assessment require baseline measurements that can be tracked over time to distinguish anthropogenic versus natural changes to the Earth system. Disasters like the Deepwater Horizon Oil Spill require constant monitoring to assess the potential environmental and economic impacts. Absolute calibration and validation of Earth-observing sensors is needed to allow for comparison of temporally separated data sets and provide accurate information to policy makers. The Ball Experimental Sea Surface Temperature (BESST) radiometer was designed and built by Ball Aerospace to provide a well calibrated measure of sea surface temperature (SST) from an unmanned aerial system (UAS). Currently, emissive skin SST observed by satellite infrared radiometers is validated by shipborne instruments that are expensive to deploy and can only take a few data samples along the ship track to overlap within a single satellite pixel. Implementation on a UAS will allow BESST to map the full footprint of a satellite pixel and perform averaging to remove any local variability due to the difference in footprint size of the instruments. It also enables the capability to study this sub-pixel variability to determine if smaller scale effects need to be accounted for in models to improve forecasting of ocean events. In addition to satellite sensor validation, BESST can distinguish meter scale variations in SST which could be used to remotely monitor and assess thermal pollution in rivers and coastal areas as well as study diurnal and seasonal changes to bodies of water that impact the ocean ecosystem. BESST was recently deployed on a conventional Twin Otter airplane for measurements over the Gulf of Mexico to access the thermal properties of the ocean surface being affected by the oil spill. Results of these measurements will be presented along with ancillary sensor data used to eliminate false signals including UV and Synthetic Aperture Radar (SAR) information. Spatial variations and day-to-day changes in the visible oil concentration on the surface of the water were observed in performing these measurements. An assessment of the thermal imagery variation will be made based on the absolute calibration of the sensor to determine if the visible variation was due to properties of the reflected light or of the actual oil composition. Comparisons with satellite data (both SAR and thermal infrared images) and buoy data will also be included.

Good, W. S.; Warden, R.; Kaptchen, P. F.; Finch, T.; Emery, W. J.

2010-12-01

5

Strong thermal leptogenesis and the absolute neutrino mass scale  

NASA Astrophysics Data System (ADS)

We show that successful strong thermal leptogenesis, where the final asymmetry is independent of the initial conditions and in particular a large pre-existing asymmetry is efficiently washed-out, favours values of the lightest neutrino mass m1gtrsim10 meV for normal ordering (NO) and m1gtrsim3 meV for inverted ordering (IO) for models with orthogonal matrix entries respecting |?ij2|lesssim2. We show analytically why lower values of m1 require a higher level of fine tuning in the seesaw formula and/or in the flavoured decay parameters (in the electronic for NO, in the muonic for IO). We also show how this constraint exists thanks to the measured values of the neutrino mixing angles and could be tightened by a future determination of the Dirac phase. Our analysis also allows us to place a more stringent constraint for a specific model or class of models, such as SO(10)-inspired models, and shows that some models cannot realise strong thermal leptogenesis for any value of m1. A scatter plot analysis fully supports the analytical results. We also briefly discuss the interplay with absolute neutrino mass scale experiments concluding that they will be able in the coming years to either corner strong thermal leptogenesis or find positive signals pointing to a non-vanishing m1. Since the constraint is much stronger for NO than for IO, it is very important that new data from planned neutrino oscillation experiments will be able to solve the ambiguity.

Di Bari, Pasquale; King, Sophie E.; Re Fiorentin, Michele

2014-03-01

6

Strong thermal leptogenesis and the absolute neutrino mass scale  

E-print Network

We show that successful strong thermal leptogenesis, where the final asymmetry is independent of the initial conditions and in particular a large pre-existing asymmetry is efficiently washed-out, favours values of the lightest neutrino mass $m_1 \\gtrsim 10\\,{\\rm meV}$ for normal ordering (NO) and $m_1 \\gtrsim 3\\,{\\rm meV}$ for inverted ordering (IO) for models with orthogonal matrix entries respecting $|\\Omega_{ij}^2| \\lesssim 2$. . We show analytically why lower values of $m_1$ require a high level of fine tuning in the seesaw formula and/or in the flavoured decay parameters (in the electronic for NO, in the muonic for IO). We also show how this constraint exists thanks to the measured values of the neutrino mixing angles and can be tighten by a future determination of the Dirac phase. Our analysis also allows to place more stringent constraint for a specific model or class of models, such as $SO(10)$-inspired models, and shows that some models cannot realise strong thermal leptogenesis for any value of $m_1$. A scatter plot analysis fully supports the analytical results. We also briefly discuss the interplay with absolute neutrino mass scale experiments concluding that they will be able in the coming years to either corner strong thermal leptogenesis or find positive signals pointing to a non-vanishing $m_1$. Since the constraint is much stronger for NO than for IO, it is very important that new data from planned neutrino oscillation experiments will be able to solve the ambiguity.

Pasquale Di Bari; Sophie E. King; Michele Re Fiorentin

2014-01-23

7

Absolute Thermal SST Measurements over the Deepwater Horizon Oil Spill  

Microsoft Academic Search

Climate monitoring and natural disaster rapid assessment require baseline measurements that can be tracked over time to distinguish anthropogenic versus natural changes to the Earth system. Disasters like the Deepwater Horizon Oil Spill require constant monitoring to assess the potential environmental and economic impacts. Absolute calibration and validation of Earth-observing sensors is needed to allow for comparison of temporally separated

W. S. Good; R. Warden; P. F. Kaptchen; T. Finch; W. J. Emery

2010-01-01

8

Signal generation mechanisms, intracavity-gas thermal-diffusivity temperature dependence, and absolute infrared emissivity measurements  

E-print Network

transfer modes were found to co-exist in the cavity. By introducing controlled variable offset dc resistive and a generalized thermal-wave resonant cavity theory is advanced, which t, and absolute infrared emissivity measurements in a thermal-wave resonant cavity Jun Shen, Andreas Mandelis

Mandelis, Andreas

9

Absolute radiometric calibration of CBERS-02 IRMSS thermal band  

Microsoft Academic Search

Based on the laboratory calibration before launch of CBERS-02 IRMSS thermal infrared channel, the onboard blackbody calibration,\\u000a the radiometric crosscalibration against TERRA MODIS corresponding channel and the in-flight field calibration at Lake Qinghai:\\u000a water surface radiometric calibration test site of China on Aug. 17, 2004 are carried out in this research. When making onboard\\u000a blackbody calibration of CBERS-02 IRMSS, it

Yong Zhang; Xingfa Gu; Tao Yu; Yuxiang Zhang; Liangfu Chen; Xiaoying Li; Xiaowen Li; Liming He

2005-01-01

10

Strong thermal leptogenesis and the absolute neutrino mass scale  

E-print Network

We show that successful strong thermal leptogenesis, where the final asymmetry is independent of the initial conditions and in particular a large pre-existing asymmetry is efficiently washed-out, favours values of the lightest neutrino mass $m_1 \\gtrsim 10\\,{\\rm meV}$ for normal ordering (NO) and $m_1 \\gtrsim 3\\,{\\rm meV}$ for inverted ordering (IO). We show analytically why lower values of $m_1$ require a high level of fine tuning in the seesaw formula and/or in the flavoured decay parameters (in the electronic for NO, in the muonic for IO). We also show how this constraint exists thanks to the measured values of the neutrino mixing angles and can be tighten by a future determination of the Dirac phase. Our analysis also allows to place more stringent constraint for a specific model or class of models, such as $SO(10)$-inspired models, and shows that some models cannot realise strong thermal leptogenesis for any value of $m_1$. A scatter plot analysis fully supports the analytical results. We also briefly di...

Di Bari, Pasquale; Fiorentin, Michele Re

2014-01-01

11

SCIENTIFIC CORRESPONDENCE Ferromagnetism and EMFs  

E-print Network

(flasks, pipettes, centrifuge tubes, and so on) and commercially prepared culture media in tissue-culture of EMF. However, any effect of EMF exposure on cultured cells, if it is due to the presence and water. We have encountered the same prob- lem in our recent attempts to grow cells in tissue culture

12

Absolute measurements of the thermal conductivity of alcohols by the transient hot-wire technique  

SciTech Connect

New absolute measurements of the thermal conductivity of methanol, ethanol, propanol, butanol, pentanol, and hexanol at atmospheric pressure and in the temperature range 290-350 K are reported. The overall uncertainty in the reported thermal conductivity data is estimated to be better than +/- 0.5%, an estimate confirmed by the measurement of the thermal conductivity of water. The measurements presented in this paper have been used to develop a consistent theoretically based correlation for the prediction of the thermal conductivity of alcohols. The proposed scheme, based on an extension of the rigid-sphere model, permits the density dependence of the thermal conductivity of alcohols, for temperatures between 290 and 350 K and atmospheric pressure, to be represented successfully by an equation containing just one parameter characteristic of the fluid at each temperature.

Assael, M.J.; Charitidou, E.; Nieto de Castro, C.A.

1988-09-01

13

EMF and the public health  

SciTech Connect

The availability of reasonably priced electric power underpins the American standard of living, the nation`s industrial strength, and even our creature comforts. Utility experts estimate that by the end of this century electric utility infrastructure such as transmission lines, distribution lines, substations, and the like will expand by as much as 15 percent to serve increased customer demands for power. The electric utility industry today, however, is faced with an unanticipated consequence of its own success as health questions have been raised regarding electric and magnetic fields (EMF or EMR). These fields are created whenever electric current passes through power lines or electrical equipment. While people are exposed to EMF from electrical appliances, household wiring, and even household water pipes to which the home electrical system has been grounded, most of the attention has centered on high-voltage transmission lines and, to a lesser extent, neighborhood distribution lines. The scientific debate has been fueled by epidemiological studies. Epidemiology, which is the study of the distribution of diseases in the human population, is useful in identifying statistical associations that may reflect a causal relationship between an exposure and a disease. Some EMF epidemiological studies have reported positive statistical associations between residential and occupational exposures to EMF and certain childhood and adult cancers, including leukemia, brain cancer, lymphoma, and breast cancer. While scientists debate the meaning of these studies and conduct further studies, the debate is now moving into America`s courtrooms as private litigants seek compensation for physical harm and damage to property values.

Krieger, R.W. [Krieger & Associates, Washington, DC (United States); Withey, M.E. [Shroeter, Goldmark & Bender, Seattle, WA (United States)

1994-12-31

14

MOF to EMF: there and back again  

Microsoft Academic Search

The OMG's Meta-Object Facility (MOF) and the open source Eclipse Modelling Framework (EMF) are two popular meta-modelling frameworks, created to meet similar (but not identical) requirements. A means of translating MOF to EMF and vice versa is required to enable the two communities to leverage one another's specifications. This paper explains the relationship between the MOF and EMF meta-models and

Anna Gerber; Kerry Raymond

2003-01-01

15

EMF: Liability, prudent avoidance, and communication  

Microsoft Academic Search

The authors conclude that there is a growing need for utilities to be truly sensitive to public concerns about potential EMF health risks. It is not in a utility's long-term litigation interest - or other interest - to adopt a position on EMF health issues that does not fully recognize the nature and extent of the current scientific inquiry. Nor

Tom Watson; Mark Warnquist

1991-01-01

16

Securing insurance coverage for EMF claims  

SciTech Connect

When confronted with lawsuits resulting from EMF-related claims, utilities must aggressively work to ensure that they receive the full protection and defense due them by their insurance companies. Within the last two years, electric utilities have been increasingly subject to claims alleging that plaintiffs have suffered bodily injury as a result of exposure to electromagnetic fields (EMF) and that this exposure has caused everything from emotional distress to cancer. The plaintiffs generally claim that EMF exposure has also caused property damage - usually in the fourth of a reduction in the value of their residence. Claims have also been made on the grounds that EMF constitutes a tresspass and nuisance, which has prevented plaintiffs from using their property to the fullest extent. While utilities may debate the degree of harm, if any, caused by exposure to EMF, one thing is certain: The current EMF claims are only the tip of the iceberg and are not likely to dissipate any time soon. As a result, utilities must example their insurance coverage to determine whether any existing or future EMF claims are covered under the company's policies. Such insurance would most likely help pay for the cost of defending against EMF lawsuits and indemnify the company if any liability is assessed.

Meyer, K.A. (Paul, Hatings, Janofsky Walker, Los Angeles, CA (United States))

1992-02-15

17

Measurement of absolute fluorescence quantum yield of basic Fuchsin solution using a dual-beam thermal lens technique.  

PubMed

The dual beam thermal lens technique is an effective method for the measurement of fluorescence quantum yield of dye solutions. The concentration-dependent quantum yield of a novel dye of triaminotriphenylmethane family in ethanol is studied using this technique. The absolute fluorescence quantum yield is measured and is observed that the reduction in the quantum yield is due to the non-radiative relaxation of the absorbed energy. PMID:24610515

Pathrose, Bini; Nampoori, V P N; Radhakrishnan, P; Mujeeb, A

2014-05-01

18

Modeling emf, Potential Difference, and Internal Resistance  

NSDL National Science Digital Library

Through class discussion and think-pair-share questions, this activity helps students come to understand the difference between emf and potential difference in electrical circuits. These concepts are broached within the context of internal resistance of batteries.

Maier, Steven

19

What Are Electric and Magnetic Fields? (EMF)  

MedlinePLUS

What are Electric and Magnetic Fields? (EMF) Electric and Magnetic Fields Electricity is an essential part of our lives. Electricity powers all sorts of things around us, from computers to refrigerators ...

20

Analysis of induced EMF waveforms and torque ripple in a brushless permanent magnet machine  

SciTech Connect

Permanent magnet machines with trapezoidal back EMF waveform have been the subject of several papers in the past. The simplicity in control and the absence of an absolute position sensor makes this type of motor very attractive. Idealized analysis of such a machine is simple and will result in trapezoidal or square wave back EMF waveforms depending on the assumptions made. In the case of an idealized quasi-square wave current excitation, a ripple-free torque will be obtained. The actual back EMF waveform of these machines depends on the flux density and the conductor distributions. This in turn is a function of the magnet magnetization and the stator tooth and slot structure. In applications where a fairly smooth torque is needed, these machines are made with either the stator slots or the rotor magnets skewed by one slot. This paper deals with the analysis of the back EMF waveform and of the torque ripple waveform of such a machine when the stator slots or rotor magnets are skewed by one slot. The analysis takes into consideration the actual stator conductor distribution and the effect of magnet magnetization on the back EMF waveform. An empirical formula is developed for the magnet flux density distribution which could be used for various magnetization conditions of the magnet. Experimental results are included to confirm the analytical results.

Sebastian, T.; Gangla, V. [Delphi Saginaw Steering Systems, MI (United States)] [Delphi Saginaw Steering Systems, MI (United States)

1996-01-01

21

Autism and EMF? Plausibility of a pathophysiological link part II.  

PubMed

Autism spectrum conditions (ASCs) are defined behaviorally, but they also involve multileveled disturbances of underlying biology that find striking parallels in the physiological impacts of electromagnetic frequency and radiofrequency radiation exposures (EMF/RFR). Part I (Vol 776) of this paper reviewed the critical contributions pathophysiology may make to the etiology, pathogenesis and ongoing generation of behaviors currently defined as being core features of ASCs. We reviewed pathophysiological damage to core cellular processes that are associated both with ASCs and with biological effects of EMF/RFR exposures that contribute to chronically disrupted homeostasis. Many studies of people with ASCs have identified oxidative stress and evidence of free radical damage, cellular stress proteins, and deficiencies of antioxidants such as glutathione. Elevated intracellular calcium in ASCs may be due to genetics or may be downstream of inflammation or environmental exposures. Cell membrane lipids may be peroxidized, mitochondria may be dysfunctional, and various kinds of immune system disturbances are common. Brain oxidative stress and inflammation as well as measures consistent with blood-brain barrier and brain perfusion compromise have been documented. Part II of this paper documents how behaviors in ASCs may emerge from alterations of electrophysiological oscillatory synchronization, how EMF/RFR could contribute to these by de-tuning the organism, and policy implications of these vulnerabilities. It details evidence for mitochondrial dysfunction, immune system dysregulation, neuroinflammation and brain blood flow alterations, altered electrophysiology, disruption of electromagnetic signaling, synchrony, and sensory processing, de-tuning of the brain and organism, with autistic behaviors as emergent properties emanating from this pathophysiology. Changes in brain and autonomic nervous system electrophysiological function and sensory processing predominate, seizures are common, and sleep disruption is close to universal. All of these phenomena also occur with EMF/RFR exposure that can add to system overload ('allostatic load') in ASCs by increasing risk, and can worsen challenging biological problems and symptoms; conversely, reducing exposure might ameliorate symptoms of ASCs by reducing obstruction of physiological repair. Various vital but vulnerable mechanisms such as calcium channels may be disrupted by environmental agents, various genes associated with autism or the interaction of both. With dramatic increases in reported ASCs that are coincident in time with the deployment of wireless technologies, we need aggressive investigation of potential ASC-EMF/RFR links. The evidence is sufficient to warrant new public exposure standards benchmarked to low-intensity (non-thermal) exposure levels now known to be biologically disruptive, and strong, interim precautionary practices are advocated. PMID:24113318

Herbert, Martha R; Sage, Cindy

2013-06-01

22

Autism and EMF? Plausibility of a pathophysiological link - Part I.  

PubMed

Although autism spectrum conditions (ASCs) are defined behaviorally, they also involve multileveled disturbances of underlying biology that find striking parallels in the physiological impacts of electromagnetic frequency and radiofrequency exposures (EMF/RFR). Part I of this paper will review the critical contributions pathophysiology may make to the etiology, pathogenesis and ongoing generation of core features of ASCs. We will review pathophysiological damage to core cellular processes that are associated both with ASCs and with biological effects of EMF/RFR exposures that contribute to chronically disrupted homeostasis. Many studies of people with ASCs have identified oxidative stress and evidence of free radical damage, cellular stress proteins, and deficiencies of antioxidants such as glutathione. Elevated intracellular calcium in ASCs may be due to genetics or may be downstream of inflammation or environmental exposures. Cell membrane lipids may be peroxidized, mitochondria may be dysfunctional, and various kinds of immune system disturbances are common. Brain oxidative stress and inflammation as well as measures consistent with blood-brain barrier and brain perfusion compromise have been documented. Part II of this paper will review how behaviors in ASCs may emerge from alterations of electrophysiological oscillatory synchronization, how EMF/RFR could contribute to these by de-tuning the organism, and policy implications of these vulnerabilities. Changes in brain and autonomic nervous system electrophysiological function and sensory processing predominate, seizures are common, and sleep disruption is close to universal. All of these phenomena also occur with EMF/RFR exposure that can add to system overload ('allostatic load') in ASCs by increasing risk, and worsening challenging biological problems and symptoms; conversely, reducing exposure might ameliorate symptoms of ASCs by reducing obstruction of physiological repair. Various vital but vulnerable mechanisms such as calcium channels may be disrupted by environmental agents, various genes associated with autism or the interaction of both. With dramatic increases in reported ASCs that are coincident in time with the deployment of wireless technologies, we need aggressive investigation of potential ASC - EMF/RFR links. The evidence is sufficient to warrant new public exposure standards benchmarked to low-intensity (non-thermal) exposure levels now known to be biologically disruptive, and strong, interim precautionary practices are advocated. PMID:24095003

Herbert, Martha R; Sage, Cindy

2013-06-01

23

New visualization strategy to study the dynamics of surgical coagulation devices in biological tissue using absolute subsurface thermal imaging  

NASA Astrophysics Data System (ADS)

Visualisation of the thermo dynamics of surgical coagulation devices like laser, diathermy and RFA devices in tissue are essential to get better understanding about the principles of operation of these devices. Thermo cameras have the ability to measure absolute temperatures. However, the visualization of temperature fields using thermal imaging has always been limited to the surface of a medium. We have developed a new strategy to look below the surface of biological tissue by viewing through a ZincSelenide window positioned alongside a block of tissue. When exposed from above with an energy source, the temperature distribution below the surface can be observed through the window. To obtain a close-up view, the thermo camera is enhanced with special macro optics. The thermo dynamics during tissue interaction of various electro surgery modes was studied in biological tissues to obtain a better understanding of the working mechanism. Simultaneously with thermal imaging, normal close-up video footage was obtained to support the interpretation of the thermal imaging. For comparison, temperature gradients were imaged inside a transparent tissue model using color Schlieren imaging. The new subsurface thermal imaging method gives a better understanding of interaction of thermal energy of surgical devices and contributes to the safety and the optimal settings for various medical applications. However, the technique has some limitations that have to be considered. The three imaging modalities showed to be both compatible and complementary showing the pro- and cons- of each modality.

Been, Stefan L.; Verdaasdonk, Rudolf M.; Klaessens, John H. G. M.

2011-03-01

24

Neo4EMF, a Scalable Persistence Layer for EMF Amine Benelallam1  

E-print Network

, is built on top of the popular graph database Neo4j. Neo4EMF is open-source, publicly available at [3) the possibility to exploit the enterprise features of Neo4j, like online backups, horizontal scalability

Paris-Sud XI, Université de

25

The absolute chronology and thermal processing of solids in the solar protoplanetary disk.  

PubMed

Transient heating events that formed calcium-aluminum-rich inclusions (CAIs) and chondrules are fundamental processes in the evolution of the solar protoplanetary disk, but their chronology is not understood. Using U-corrected Pb-Pb dating, we determined absolute ages of individual CAIs and chondrules from primitive meteorites. CAIs define a brief formation interval corresponding to an age of 4567.30 ± 0.16 million years (My), whereas chondrule ages range from 4567.32 ± 0.42 to 4564.71 ± 0.30 My. These data refute the long-held view of an age gap between CAIs and chondrules and, instead, indicate that chondrule formation started contemporaneously with CAIs and lasted ~3 My. This time scale is similar to disk lifetimes inferred from astronomical observations, suggesting that the formation of CAIs and chondrules reflects a process intrinsically linked to the secular evolution of accretionary disks. PMID:23118187

Connelly, James N; Bizzarro, Martin; Krot, Alexander N; Nordlund, Åke; Wielandt, Daniel; Ivanova, Marina A

2012-11-01

26

Absolute measurement of thermal noise in a resonant short-range force experiment  

NASA Astrophysics Data System (ADS)

Planar, double-torsional oscillators are especially suitable for short-range macroscopic force search experiments, since they can be operated at the limit of instrumental thermal noise. As a study of this limit, we report a measurement of the noise kinetic energy of a polycrystalline tungsten oscillator in thermal equilibrium at room temperature. The fluctuations of the oscillator in a high-Q torsional mode with a resonance frequency near 1 kHz are detected with capacitive transducers coupled to a sensitive differential amplifier. The electronic processing is calibrated by means of a known electrostatic force and input from a finite-element model. The measured average kinetic energy, Eexp = (2.0 ± 0.3) × 10?21 J, is in agreement with the expected value of 1/2{{k}B}T.

Yan, H.; Housworth, E. A.; Meyer, H. O.; Visser, G.; Weisman, E.; Long, J. C.

2014-10-01

27

Absolute measurement of thermal noise in a resonant short-range force experiment  

E-print Network

Planar, double-torsional oscillators are especially suitable for short-range macroscopic force search experiments, since they can be operated at the limit of instrumental thermal noise. As a study of this limit, we report a measurement of the noise kinetic energy of a polycrystalline tungsten oscillator in thermal equilibrium at room temperature. The fluctuations of the oscillator in a high-Q torsional mode with a resonance frequency near 1 kHz are detected with capacitive transducers coupled to a sensitive differential amplifier. The electronic processing is calibrated by means of a known electrostatic force and input from a finite element model. The measured average kinetic energy is in agreement with the expected value of 1/2 kT.

H. Yan; E. A. Housworth; H. O. Meyer; G. Visser; E. Weisman; J. C. Long

2014-02-02

28

LVI. The thermal conductivity of potassium chrome alum at temperatures below one degree absolute  

Microsoft Academic Search

An account is given of measurements of the thermal conductivity of potassium chrome alum made between 0·14° and 0·30° K., from which it is concluded that the mean free path of the phonons in the crystal is about 1\\/2 mm. In the method employed, a long single crystal of the salt, isolated from the outside world, is demagnetized to a

C. G. B. Garett

1950-01-01

29

Changes in gene expression following EMF exposure  

SciTech Connect

Experiments were designed to examine the effects of electromagnetic field (EMF) exposure on specific gene expression, an effect that can be deleterious, beneficial, or neutral, depending on the long-term consequences; however, the proof of a reproducible, quantitative biological effect (such as change in gene expression) will lead to latter experiments aimed at determining the relative contribution of these changes to cellular consequences. Past work by ourselves and by others has shown that measures of gene expression are extremely sensitive indicators of the cellular and biological effects of ionizing radiation, with transcriptional changes being detected by exposure of cells to doses of {gamma}-rays as low as 0.01 cGy that have no pronounced cellular consequences. On the basis of this work, the authors hypothesized that measures of gene expression will be equally sensitive to EMF effects on cells.

Woloschak, G.E.; Paunesku, T.; Chang-Liu, C.M. [Argonne National Lab., IL (United States). Center for Mechanistic Biology and Biotechnology; Loberg, L.; Gauger, J.; McCormick, D. [IIT Research Inst., Chicago, IL (United States)

1997-10-01

30

Defending against EMF property devaluation cases  

SciTech Connect

Late last year, New York`s highest court, the Court of Appeals, ruled that the owner of property adjacent to a utility`s high-power electrical transmission lines could seek damages for a decrease in the market value of the property caused by the fear that the power lines might cause cancer, even if such a fear was not medically or scientifically reasonable. That decision has already begun to change the outlook on electromagnetic field (EMF) litigation for utilities.

Brandon, G. [Milbank, Tweed, Hadley & McCloy, New York, NY (United States)

1995-02-01

31

Prognostic value of preoperative absolute lymphocyte count in recurrent hepatocellular carcinoma following thermal ablation: a retrospective analysis  

PubMed Central

Purpose To investigate the prognostic value of preoperative absolute lymphocyte count (ALC) in recurrent hepatocellular carcinoma (RHCC) following thermal ablation. Materials and methods We retrospectively analyzed the relationship between preoperative ALC and the clinicopathologic factors and long-term prognosis in 423 RHCC patients who underwent curative thermal ablation. Correlation analysis, receiver operating characteristic (ROC) calculation, Kaplan–Meier curves, and multivariate regression were used for statistical analysis. Results The median time to recurrence was 12 months for RHCC patients after thermal ablation. On multivariate Cox regression analysis, preoperative ALC was an independent risk factor for cancer recurrence, along with tumor differentiation and ?-fetoprotein level. ALC ?1.64×109/L defined by ROC calculation was associated with prolonged survival (area under the curve 0.741, P<0.001). Patients with ALC ?1.64×109/L showed a mean survival of 20.2 months versus 11.6 months for patients with ALC <1.64×109/L (P<0.001). Patients were stratified into high and low groups according to ALC status. After excluding the basic parameters between groups, the 1- and 3-year recurrence rates in the high group were 20.9% and 29.5%, respectively, which were significantly lower than those of the low group (58.4% and 71.9%, respectively; P<0.001). The recurrence-free survival rates in the two groups analyzed by Kaplan–Meier curves were significantly different (P<0.001). Conclusion Preoperative ALC is a powerful prognostic factor for RHCC recurrence after thermal ablation, which suggests that maintaining a high ALC in RHCC patients might improve cancer outcomes. PMID:25336974

Li, Xin; Han, Zhiyu; Cheng, Zhigang; Yu, Jie; Yu, Xiaoling; Liang, Ping

2014-01-01

32

The Absolute Isotopic Composition of Zn in Terrestrial Materials Determined Using Double Spike Thermal Ionization Mass Spectrometry  

NASA Astrophysics Data System (ADS)

Although long suspected to be widespread in nature, until recently, little was known about the extent of the variation of the isotopic composition, or isotopic fractionation, of Zn in natural materials. During the last decade an increasing number of high precision Zn isotopic fractionation data have been reported using MC- ICP-MS (MARECHAL et al., 1999; PETIT et al., 2008; PICHAT et al., 2003), but none have been reported on an absolute scale which is essential for interlaboratory comparison of results. In this work we report sub- permil Zn fractionation in a range of natural materials relative to the internationally proposed absolute Zn isotopic reference material (? zero) (PONZEVERA et al., 2006)using the Thermal Ionization Mass Spectrometry double spike technique. Repeated double spike analysis of the laboratory standard relative to itself demonstrated a long term reproducibility of +0.006 ± 0.039 permil amu-1. The measured isotopic composition of Zn in minerals and igneous rocks SRMs was found to be the same as the proposed absolute (? zero) which makes it possible to consider the proposed absolute Zn isotopic standard as being representative of "bulk earth" Zn. A significant and consistent fractionation of ~+0.3 permil amu-1 was found in 5 sediments from a range of localities. The results obtained for metamorphic SRMs indicate that the fractionation of Zn in these rocks is the same as found in igneous rocks but are different from the Zn found in sedimentary rocks. A clay SRM sample TILL-3 appears to exhibit a consistently Zn fractionation of +0.12 ± 0.10 permil amu-1. The isotopic composition of Zn was also measured in two plant SRMs and one animal SRM sample. The fractionation of (-0.088 ± 0.070 permil amu-1) of Zn in the Rice (a C3 type plant material) sample suggested that Zn may be used to study Zn systematics in plants. The result obtained for MURST-ISS-A2 (Antarctic Krill) was +0.21 ± 0.11 permil amu-1 relative to the laboratory standard which is similar to the average Zn fractionation results of +0.281 ± 0.083 permil amu-1 obtained for marine sediments. The fractionation of Zn in seven ultra pure Zn standard materials was also measured relative to the laboratory standard and found to range from -5.11 ± 0.36 permil amu-1 for AE 10760 to +0.12 ± 0.16 permil amu-1 for Zn IRMM 10440 confirming that that significant care must be exercised in the selection of Zn isotope laboratory standards (TANIMIZU et al., 2002). A pilot study to determine the concentration and the isotopic composition of Zn in river and tap water, and a number of processed materials was also performed. The implications and applications of these results, such as on the atomic weight of Zn will be presented.

Ghidan, O. Y.; Loss, R. D.

2008-12-01

33

Development of an EMF Measurments Database, EMF Rapid Program, Project #5, Interim Report: April 1995-December 1996  

SciTech Connect

The EMF Measurements Database project is being implemented by T. Dan Bracken, Inc. as part of the EMF Research and Public Information Dissemination (EMF RAPID) Program. The Database is a collection of data sets that relate to measurement of electric and/or magnetic fields. This report describes activities during the period January 1997 to March 1998. Primary goals for the EMF Measurements Database are to develop a database structure that can accommodate the diversity of EMF data sets, provide guidance for production of future EMF data sets, and serve as an accessible repository of EMF measurement data. Specific objectives of the EMF Measurements Database are: o to presewe study descriptions, results and data; o to provide readily accessible, well-documented data; and - o to facilitate communication among researchers. In addition, the EMF Measurements Database will encourage additional analysis of existing data sets, facilitate analysis of data from multiple projects, support design of new studies, and permit future issues in EMF exposure assessment to be addressed with existing data. Preservation of study descriptions and data is accomplished with a formal, but open, structure. Specifications have been developed for the various elements of the database. Each data set in the database is formally described by a metadata file. The structured metadata file describes the origin, development, logical and physical structure, and distribution mechanism for each data set. The metadata for each data set is generated according to a specification developed for the EMF Measurements Database. The actual measurement data is contained in data products for each data set. The number and type of data product will vary by data set. Most of the data products available from the EMF Measurements Database can be downloaded from an Internet site. For some data sets, the data products will be maintained by other patties who may have their own access procedures.

T. Dan Bracken, Inc.

1998-03-01

34

Girdling Affects Ectomycorrhizal Fungal (EMF) Diversity and Reveals Functional Differences in EMF Community Composition in a Beech Forest? †  

PubMed Central

The relationships between plant carbon resources, soil carbon and nitrogen content, and ectomycorrhizal fungal (EMF) diversity in a monospecific, old-growth beech (Fagus sylvatica) forest were investigated by manipulating carbon flux by girdling. We hypothesized that disruption of the carbon supply would not affect diversity and EMF species numbers if EM fungi can be supplied by plant internal carbohydrate resources or would result in selective disappearance of EMF taxa because of differences in carbon demand of different fungi. Tree carbohydrate status, root demography, EMF colonization, and EMF taxon abundance were measured repeatedly during 1 year after girdling. Girdling did not affect root colonization but decreased EMF species richness of an estimated 79 to 90 taxa to about 40 taxa. Cenococcum geophilum, Lactarius blennius, and Tomentella lapida were dominant, colonizing about 70% of the root tips, and remained unaffected by girdling. Mainly cryptic EMF species disappeared. Therefore, the Shannon-Wiener index (H?) decreased but evenness was unaffected. H? was positively correlated with glucose, fructose, and starch concentrations of fine roots and also with the ratio of dissolved organic carbon to dissolved organic nitrogen (DOC/DON), suggesting that both H? and DOC/DON were governed by changes in belowground carbon allocation. Our results suggest that beech maintains numerous rare EMF species by recent photosynthate. These EM fungi may constitute biological insurance for adaptation to changing environmental conditions. The preservation of taxa previously not known to colonize beech may, thus, form an important reservoir for future forest development. PMID:20097809

Pena, Rodica; Offermann, Christine; Simon, Judy; Naumann, Pascale Sarah; Geßler, Arthur; Holst, Jutta; Dannenmann, Michael; Mayer, Helmut; Kögel-Knabner, Ingrid; Rennenberg, Heinz; Polle, Andrea

2010-01-01

35

Development of an EMF Measurements Database, EMF Rapid Program, Project #5, Interim Report: April 1995-December 1996  

SciTech Connect

The EMF measurement data sets in existence today were compiled with varying goals and techniques. Consequently, they have different information content as well as varying logical and physical structure. Future studies will continue to pursue varying goals and utilize techniques that cannot be known in advance. Primary goals for the EMF Measurements Database developed under the Department of Energy EMF RAPID Program are to develop a database structure that can accommodate the diversity of EMF data sets, provide guidance for production of future EMF data sets, and serve as an accessible repository of EMF measurement data. Specific objectives of the EMF Measurements Database are: o to preserve study descriptions, results and data; o to provide readily accessible, well-documented data; and o to facilitate communication among researchers. In addition, the EMF Measurements Database will encourage additional analysis of existing data sets, facilitate analysis of data from multiple projects, support design of new studies, and permit future issues in EMF exposure assessment to be addressed with existing data. Preservation of study descriptions and data is accomplished with a formal, but open, structure. Specifications have been developed for the various elements of the database. Each data set in the database is formally described by a metadata file. The structured metadata file describes the origin, development, logical and physical structure and distribution mechanism for each data set. The metadata for each data set is generated according to a specification developed for the EMF Measurements Database. The actual measurement data is contained in data Products for each data set. The number and type of data product will vary by data set. Most of the data products in the possession of the EMF Measurements Database are available for download from an Internet site. For some data sets, the data products will be maintained by other parties who may have their own access procedures. In addition, data set contributors or users can provide reports that describe results of the study and analysis of the data with text and figures. Guidelines have been developed for preparation of reports. Access to the EMF Measurements Database is provided via an Internet site (http://www.emf-data. erg). The site provides descriptive information in a home page, . . access to data products with a file transfer protocol (ftp) address, and links to other EMF-related sites.

T. Dan Bracken, Inc.

1997-04-01

36

Absolutely relativity  

NASA Astrophysics Data System (ADS)

The light speed constancy is proved here and then it is not a principle suppose it is a proposition proved absolutely based on the Galilean transformation and simultaneity and this is a book full from new discoveries along the absolutely proof for Lorentz transformation. Even in a page I have proved Lorentz transformation by the brawer constant point based on the Galilean transformation until to show easily it is possible to generate absolutely relativity and this is not ether theorem suppose we are upon the new discoveries all mathematical and complete, not a theory.

Lutephy, Mohsen

2012-03-01

37

EMF Monitoring--Concepts, Activities, Gaps and Options  

PubMed Central

Exposure to electromagnetic fields (EMF) is a cause of concern for many people. The topic will likely remain for the foreseeable future on the scientific and political agenda, since emissions continue to change in characteristics and levels due to new infrastructure deployments, smart environments and novel wireless devices. Until now, systematic and coordinated efforts to monitor EMF exposure are rare. Furthermore, virtually nothing is known about personal exposure levels. This lack of knowledge is detrimental for any evidence-based risk, exposure and health policy, management and communication. The main objective of the paper is to review the current state of EMF exposure monitoring activities in Europe, to comment on the scientific challenges and deficiencies, and to describe appropriate strategies and tools for EMF exposure assessment and monitoring to be used to support epidemiological health research and to help policy makers, administrators, industry and consumer representatives to base their decisions and communication activities on facts and data. PMID:25216256

Durrenberger, Gregor; Frohlich, Jurg; Roosli, Martin; Mattsson, Mats-Olof

2014-01-01

38

Human health effects of EMFs: The cost of doing nothing  

NASA Astrophysics Data System (ADS)

Everyone is exposed to electromagnetic fields (EMFs) from electricity (extremely low frequency, ELF), communication frequencies and wireless devices (radiofrequency, RF), as well as naturally occurring EMFs. Concern of health hazards from EMFs has increased as the use of mobile phones and other wireless devices has grown in all segments of the population, especially children. While there has been strong evidence for an association between leukemia and residential or occupational exposure to ELF EMFs for many years, the standards in existence are not sufficiently stringent to protect from an increased risk of cancer. ELF EMFs also increase risk of at least two types of neurodegenerative diseases. For RF EMFs, standards are set at levels designed to avoid tissue heating, in spite of many reports of biological effects at intensities too low to cause significant heating. Recent evidence demonstrates elevations in risk of brain cancer and acoustic neuroma only on the side of the head where individuals used their mobile phone. Individuals who begin exposure at younger ages are more vulnerable. These data indicate that the existing standards for radiofrequency exposure are not adequate. While there are many unanswered questions, the cost of doing nothing may result in an increasing number of people, many of them young, developing these diseases.

Carpenter MD, David O.

2010-04-01

39

NEWS AND INFORMATION: Classification of EMFs from California  

Microsoft Academic Search

California Department Of Health Services has now released the `fourth and final' draft of its `Evaluation of the possible risks from electric and magnetic fields (EMFs) from power lines, internal wiring, electrical occupations and appliances'. The third draft was released for public comment in 2001. The main conclusion is expressed thus: `To one degree or another all three of the

John Swanson

2002-01-01

40

A precautionary tale: the British response to cell phone EMF  

Microsoft Academic Search

The UK led the campaign for precautionary responses to cell phone EMF. The experience which informed this approach was BSE, a disease that originated and had greatest impact in the UK. Unsurprisingly, British politicians have responded even more directly than the EU to the cell phone issue, seeking to prove that they have \\

Adam Burgess

2002-01-01

41

INVITED EDITORIAL: Do we know enough about EMF-induced health effects?  

Microsoft Academic Search

Responsible Officer, International EMF Project, World Health Organization, 1211 Geneva 27, Switzerland In this issue Dr Zenon Sienkiewicz summarises the biological effects of exposure to electromagnetic fields (EMF). He concludes that there are few established consequences of EMF exposure at levels normally encountered by members of the general public, and that any health risk from these fields is likely to

Michael H. Repacholi

1998-01-01

42

Review of the epidemiologic literature on EMF and Health.  

PubMed Central

Exposures to extremely low-frequency electric and magnetic fields (EMF) emanating from the generation, transmission, and use of electricity are a ubiquitous part of modern life. Concern about potential adverse health effects was initially brought to prominence by an epidemiologic report two decades ago from Denver on childhood cancer. We reviewed the now voluminous epidemiologic literature on EMF and risks of chronic disease and conclude the following: a) The quality of epidemiologic studies on this topic has improved over time and several of the recent studies on childhood leukemia and on cancer associated with occupational exposure are close to the limit of what can realistically be achieved in terms of size of study and methodological rigor. b) Exposure assessment is a particular difficulty of EMF epidemiology, in several respects: i) The exposure is imperceptible, ubiquitous, has multiple sources, and can vary greatly over time and short distances. ii) The exposure period of relevance is before the date at which measurements can realistically be obtained and of unknown duration and induction period. iii) The appropriate exposure metric is not known and there are no biological data from which to impute it. c) In the absence of experimental evidence and given the methodological uncertainties in the epidemiologic literature, there is no chronic disease for which an etiological relation to EMF can be regarded as established. d) There has been a large body of high quality data for childhood cancer, and also for adult leukemia and brain tumor in relation to occupational exposure. Among all the outcomes evaluated in epidemiologic studies of EMF, childhood leukemia in relation to postnatal exposures above 0.4 microT is the one for which there is most evidence of an association. The relative risk has been estimated at 2.0 (95% confidence limit: 1.27-3.13) in a large pooled analysis. This is unlikely to be due to chance but, may be, in part, due to bias. This is difficult to interpret in the absence of a known mechanism or reproducible experimental support. In the large pooled analysis only 0.8% of all children were exposed above 0.4 microT. Further studies need to be designed to test specific hypotheses such as aspects of selection bias or exposure. On the basis of epidemiologic findings, evidence shows an association of amyotrophic lateral sclerosis with occupational EMF exposure although confounding is a potential explanation. Breast cancer, cardiovascular disease, and suicide and depression remain unresolved. PMID:11744509

Ahlbom, I C; Cardis, E; Green, A; Linet, M; Savitz, D; Swerdlow, A

2001-01-01

43

Three-phase power factor controller with induced EMF sensing  

NASA Technical Reports Server (NTRS)

A power factor controller for an ac induction motor is provided which is of the type comprising thyristor switches connected in series with the motor, phase detectors for sensing the motor current and voltage and providing an output proportional to the phase difference between the motor voltage and current, and a control circuit, responsive to the output of the phase detector and to a power factor command signal, for controlling switching of the thyristor. The invention involves sensing the induced emf produced by the motor during the time interval when the thyristor is off and for producing a corresponding feedback signal for controlling switching of the thyristor. The sensed emf is also used to enhance soft starting of the motor.

Nola, F. J. (inventor)

1984-01-01

44

Cryogenic, Absolute, High Pressure Sensor  

NASA Technical Reports Server (NTRS)

A pressure sensor is provided for cryogenic, high pressure applications. A highly doped silicon piezoresistive pressure sensor is bonded to a silicon substrate in an absolute pressure sensing configuration. The absolute pressure sensor is bonded to an aluminum nitride substrate. Aluminum nitride has appropriate coefficient of thermal expansion for use with highly doped silicon at cryogenic temperatures. A group of sensors, either two sensors on two substrates or four sensors on a single substrate are packaged in a pressure vessel.

Chapman, John J. (Inventor); Shams. Qamar A. (Inventor); Powers, William T. (Inventor)

2001-01-01

45

The process of consensus on EMF: SAB review of the EPA draft document on EMF and cancer  

SciTech Connect

The EPA Draft Document on EMF and Cancers grew out of an earlier effort by EPA to track biological effects literature relative to radio-frequency (RF) exposure. Scope of the document was broadened to include extremely low frequency electric and magnetic fields prior to an announcement in 1986 that EPA would formally review the whole area of non-ionizing radiation. An extensive survey of the relevant bioeffects and epidemiologic literature was carried out, and writing on the document began in earnest on the document sometime in 1989. In its draft form, the document reviewed the literature on mechanisms of Interaction between electromagnetic fields and biological tissue, EMF epidemiologic studies, supporting evidence for carcinogenicity and research needs. In the early summer of 1990, a draft of the document was reviewed by some 22 individuals within the EPA and other government agencies. It was also sent out for external review to an additional 9 qualified scientists who had worked in the area and were familiar with EMF-related literature in epidemiology, biology, and physics. Many of the comments sent to EPA from this first review, prior to release of the draft for public comment, were strikingly similar to those resulting from the second (public) review process. Thus, it appears that much of the controversy that was later associated with the document could have been avoided had the authors been diligent in following the recommendations of the initial set of reviewers.

Wilson, B.W.

1992-06-01

46

Children's health and RF EMF exposure. Views from a risk assessment and risk communication perspective  

Microsoft Academic Search

\\u000a Zusammenfassung  Ein Review der epidemiologischen Studien zu den Auswirkungen von HF EMF-Expositionen auf Tumorbildung und Leukämieerkrankungen\\u000a bei Kindern sowie experimentellen Untersuchungen zu Effekten von HF EMF-Expositionen auf Kognition und ZNS bei Kindern, das\\u000a die wissenschaftliche Literatur bis August 2010 umfasst, findet keine oder nur unzureichende wissenschaftliche Evidenz für\\u000a die Annahme, dass HF EMF ein Risikofaktor für Kinder ist. Dieser Befund steht

Peter Wiedemann; Holger Schütz

2011-01-01

47

Rate of rotation measurement using back-EMFS associated with windings of a brushless DC motor  

NASA Technical Reports Server (NTRS)

A system and method are provided for measuring rate of rotation. A brushless DC motor is rotated and produces a back electromagnetic force (emf) on each winding thereof. Each winding's back-emf is integrated and multiplied by the back-emf associated with an adjacent winding. The multiplied outputs associated with each winding are combined to produce a directionally sensitive DC output proportional only to the rate of rotation of the motor's shaft.

Howard, David E. (Inventor)

2000-01-01

48

Environmental Field Surveys, EMF Rapid Program, Engineering Project No.3  

SciTech Connect

The EMF Research and Public Information Dissemination Program (RAPID) includes several engineering research in the area of exposure assessment and source characterization. RAPID engineering project No. 3: ''Environmental Field Surveys'' was performed to obtain information on the levels and characteristics of different environments, for which only limited data were available, especially in comparison to magnetic field data for the residential environment and for electric utility facilities, such as power lines and substations. This project was also to provide information on the contribution of various field sources in the surveyed environments. Magnetic field surveys were performed at four sites for each of five environments: schools, hospitals, office buildings, machine shops, and grocery stores. Of the twenty sites surveyed, 11 were located in the San Francisco Bay Area and 9 in Massachusetts. The surveys used a protocol based on magnetic field measurements and observation of activity patterns, designed to provide estimates of magnetic field exposure by type of people and by type of sources. The magnetic field surveys conducted by this project produced a large amount of data which will form a part of the EMF measurement database Field and exposure data were obtained separately for ''area exposure'' and ''at exposure points''. An exposure point is a location where persons engage in fixed, site specific activities near a local source that creates a significant increase in the area field. The area field is produced by ''area sources'', whose location and field distribution is in general not related to the location of the people in the area.

Enertech Consultants

1996-04-01

49

Electric fields in accelerating conductors: measurement of the EMF in rotationally accelerating coils  

Microsoft Academic Search

The acceleration of an electric conductor is predicted to produce an electric field proportional to m\\/q where m is the free mass and q the charge of the carriers of the electric current. In certain configurations this leads to a measurable EMF. In this paper we report a measurement of the EMF produced by rotationally accelerating coils of aluminium and

Gareth F. Moorhead; Geoffrey I. Opat

1996-01-01

50

Study of uranium solubility in gallium-indium eutectic alloy by emf method  

NASA Astrophysics Data System (ADS)

Activity, activity coefficients and solubility of uranium in Ga-In eutectic alloy as well as activity of uranium in U-Ga and U-In alloys were determined between 573 and 1073 K using electromotive force (emf) method.

Volkovich, V. A.; Maltsev, D. S.; Yamshchikov, L. F.; Osipenko, A. G.; Raspopin, S. P.; Kormilitsyn, M. V.

2013-02-01

51

4 Hz EMF treated physiological solution depresses Ach-induced neuromembrane current.  

PubMed

The effect of 4 Hz EMF treated physiological solution (PS) on acetylcholine (Ach) sensitivity of the snail neuron was studied. The 4 Hz EMF treated normal PS at room temperature (23 degrees C) has a depressing effect on Ach induced current, while in cold medium (12 degrees C) this effect disappeared. EMF treated, ouabain containing, K-free PS elevates the Ach-induced current at room temperature. It is suggested that the metabotropic effect of EMF treated PS is due to the activation of cGMP-dependent Na:Ca exchange, leading to the decrease of the number of functional active receptors in the membrane, through Na-K pump-induced cell shrinkage, and to increase the receptors affinity to Ach, as the result of decrease of intracellular Ca concentration. PMID:15197765

Ayrapetyan, S N; Hunanyan, A Sh; Hakobyan, S N

2004-07-01

52

[FTIR spectra investigation of rat sensitive tissues exposure to ELF-EMF].  

PubMed

Nonthermal effects of extremely low frequency electromagnetic fields (ELF-EMF) are related to changes in the microstructure of biological tissues after exposure to electromagnetic radiation. Fourier transform infrared spectroscopy (FTIR) analysis method can effectively study the mechanisms of biological effects of electromagnetic radiation. The present paper studies the characteristics of sensitive tissues of rat after ELF-EMF exposure. FTIR analysis of sensitive tissues of control group and experimental group showed that 50 Hz, 0.75 mT ELF-EMF exposure for 20 days can affect molecular level of the rat testis, blood and brain. Experimental results show that regular changes in absorption peak positions and intensity in the spectra of sensitive tissue may be caused by exposure to ELF-EMF, therefore, Fourier transform infrared spectroscopy is an effective means to study mechanism of biological effects of electromagnetic fields. PMID:22827052

Li, Gun; Yan, Ya-jing; Huang, Yong; Zhou, Yan; Pang, Xiao-feng

2012-05-01

53

EMF 7 model comparisons: key relationships and parameters  

SciTech Connect

A simplified textbook model of aggregate demand and supply interprets the similarities and differences in the price and income responses of the various EMF 7 models to oil and policy shocks. The simplified model is a marriage of Hicks' classic IS-LM formulation of the Keynesian theory of effective demand with a rudimentary model of aggregate supply, combining a structural Phillips curve for wage determination and a markup theory of price determination. The reduced-form income equation from the fix-price IS-LM model is used to define an aggregate demand (AD) locus in P-Y space, showing alternative pairs of the implicit GNP deflator and real GNP which would simultaneously satisfy the saving-investment identity and the condition for money market equilibrium. An aggregate supply (AS) schedule is derived by a similar reduction of relations between output and labor demand, unemployment and wage inflation, and the wage-price-productivity nexus governing markup pricing. Given a particular econometric model it is possible to derive IS and LM curves algebraically. The resulting locuses would show alternative combinations of interest rate and real income which equilibrate real income identity on the IS side and the demand and supply of money on the LM side. By further substitution the reduced form fix-price income relation could be obtained for direct quantification of the AD locus. The AS schedule is obtainable by algebraic reduction of the structural supply side equations.

Hickman, B.G.

1983-12-01

54

Modelling indoor electromagnetic fields (EMF) from mobile phone base stations for epidemiological studies.  

PubMed

Radio frequency electromagnetic fields (RF-EMF) from mobile phone base stations can be reliably modelled for outdoor locations, using 3D radio wave propagation models that consider antenna characteristics and building geometry. For exposure assessment in epidemiological studies, however, it is especially important to determine indoor exposure levels as people spend most of their time indoors. We assessed the accuracy of indoor RF-EMF model predictions, and whether information on building characteristics could increase model accuracy. We performed 15-minute spot measurements in 263 rooms in 101 primary schools and 30 private homes in Amsterdam, the Netherlands. At each measurement location, we collected information on building characteristics that can affect indoor exposure to RF-EMF, namely glazing and wall and window frame materials. Next, we modelled RF-EMF at the measurement locations with the 3D radio wave propagation model NISMap. We compared model predictions with measured values to evaluate model performance, and explored if building characteristics modified the association between modelled and measured RF-EMF using a mixed effect model. We found a Spearman correlation of 0.73 between modelled and measured total downlink RF-EMF from base stations. The average modelled and measured RF-EMF were 0.053 and 0.041mW/m(2), respectively, and the precision (standard deviation of the differences between predicted and measured values) was 0.184mW/m(2). Incorporating information on building characteristics did not improve model predictions. Although there is exposure misclassification, we conclude that it is feasible to reliably rank indoor RF-EMF from mobile phone base stations for epidemiological studies. PMID:24632329

Beekhuizen, J; Vermeulen, R; van Eijsden, M; van Strien, R; Bürgi, A; Loomans, E; Guxens, M; Kromhout, H; Huss, A

2014-06-01

55

Survey and assessment of electric and magnetic field (EMF) public exposure in the transportation environment  

Microsoft Academic Search

This research, conducted under the support of the Federal Electric and Magnetic Field Research and Public Information Dissemination (EMF RAPID) Engineering Program, characterized the extreme-low-frequency (ELF) electric and magnetic fields (EMF) which a traveler might encounter while using various forms of transportation. Extensive measurement of field level, frequency, temporal variability and spatial variability are reported for: conventional internal-combustion cars, trucks

F. M. Dietrich; W. L. Jacobs

1999-01-01

56

Absolute nuclear material assay  

DOEpatents

A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

Prasad, Manoj K. (Pleasanton, CA); Snyderman, Neal J. (Berkeley, CA); Rowland, Mark S. (Alamo, CA)

2012-05-15

57

Experimental study of the effects of annealing time, equilibrium angle, and absolute misorientation angle on thermal grain-boundary groving in cube- texture nickel.  

National Technical Information Service (NTIS)

Several technical problems are associated with the rolling-assisted biaxially-textured substrates (RABiTS) method of fabricating long lengths of high-temperature superconducting wire. For example, controlling or eliminating thermal grain-boundary groove d...

Conrad, J. Simon

1999-01-01

58

Measuring Absolute Oxygen Pressure  

NASA Technical Reports Server (NTRS)

Sensor determines absolute pressure of oxygen without reference pressure source. Absolute oxygen pressure transducer with control circuit enables measurement without reference pressure. Transducer, two part device, combines solid electrolyte membranes sensor with diffusional orifice. Device adapted for direct control of oxygen pressure in combustion mixtures.

Richter, R.

1985-01-01

59

Recommendations for Guidelines for EMF Personal Exposure Measurements, Rapid Project #4  

SciTech Connect

The purpose of developing guidelines for electric and magnetic field (EMF) personal exposure measurements (lF'EM) is to ensure reliable and comparable data across I?EM studies. Study techniques may vary due to different populations or objectives, but the resulting data should be consistently reported and comparable, to the extent possible. Any guideline must allow creativity by the research-oriented investigator and provide specific guidance to industrial hygienists or other results-oriented investigators, requiring a standard protocol. Recognizing measurement studies with different purposes is an important aspect of these recommendations. The guidelines presented here intend to produce comparable data across studies while remaining flexible. The recommendations for designing and implementing an EMF PEM program describe a three-stage process. The first step is to clearly state the purpose of the PEM program. The next stage addresses the fundamental elements of an EMF PEM study, including an assessment of the scientific and organizational resources that will be required. This process is codified in a written study plan. These stages are described in 1 Section 5 of this report. The third stage of a PEM study involves the design, implementation and documentation of specific procedures and protocols fo~ sampling strategies, selection of measurement parameters; instrumentation, measurement and data collection, data management, data analysis, quality assurance, uncertainty evaluation, and archiving the study methods and results. The methods for designing these elements of an EMF PEM study are described in Section 6: Specific Guidelines for EMF I?EM Study Design.

T. Dan Bracken, Inc.

1997-08-01

60

Effect of Extremely Low Frequency Electromagnetic Fields (EMF) on Phospholipase Activity in the Cultured Cells  

PubMed Central

This study was conducted to investigate the effects of extremely low frequency electromagnetic fields (EMF) on signal pathway in plasma membrane of cultured cells (RAW 264.7 cells and RBL 2H3 cells), by measuring the activity of phospholipase A2 (PLA2), phospholipase C (PLC) and phospholipase D (PLD). The cells were exposed to the EMF (60 Hz, 0.1 or 1 mT) for 4 or 16 h. The basal and 0.5 µM melittin-induced arachidonic acid release was not affected by EMF in both cells. In cell-free PLA2 assay, we failed to observe the change of cPLA2 and sPLA2 activity. Also both PLC and PLD activities did not show any change in the two cell lines exposed to EMF. This study suggests that the exposure condition of EMF (60 Hz, 0.1 or 1 mT) which is 2.4 fold higher than the limit of occupational exposure does not induce phospholipases-associated signal pathway in RAW 264.7 cells and RBL 2H3 cells. PMID:21311685

Song, Ho Sun; Kim, Hee Rae; Ko, Myoung Soo; Jeong, Jae Min; Kim, Yong Ho; Kim, Myung Cheul; Hwang, Yeon Hee; Sohn, Uy Dong; Gimm, Yoon-Myoung; Myung, Sung Ho

2010-01-01

61

Absolute Biodiesel Potential Country Name  

E-print Network

Absolute Biodiesel Potential Country Name Production Cost ($/liter) Potential Biodiesel Volume,234 0% 0% #12;Absolute Biodiesel Potential Country Name Production Cost ($/liter) Potential Biodiesel;Absolute Biodiesel Potential Country Name Production Cost ($/liter) Potential Biodiesel Volume (liters

Wisconsin at Madison, University of

62

Comparison of a triaxial fluxgate magnetometer and Toftness sensometer for body surface EMF measurement  

PubMed Central

Introduction The use of magnetic fields to treat disease has intrigued mankind since the time of the ancient Greeks. More recently it has been shown that electromagnetic field (EMF) treatment aids bone healing, and repetitive transcranial magnetic stimulation (rTMS) appears to be beneficial in treating schizophrenia and depression. Since external EMFs influence internal body processes, we hypothesized that measurement of body surface EMFs might be used to detect disease states and direct the course of subsequent therapy. However, measurement of minute body surface EMFs requires use of a sensitive and well documented magnetometer. In this study we evaluated the sensitivity and frequency response of a fluxgate magnetometer with a triaxial probe for use in detecting body surface EMF and we compared the magnetometer readings with a signal from a Toftness Sensometer, operated by an experienced clinician, in the laboratory and in a clinical setting. Methods A Peavy Audio Amplifier and variable power output Telulex signal generator were used to develop 50 ?T EMFs in a three coil Merritt coil system. A calibrated magnetometer was used to set a 60 Hz 50 ?T field in the coil and an ammeter was used to measure the current required to develop the 50 ?T field. At frequencies other than 60 Hz, the field strength was maintained at 50 ?T by adjusting the Telulex signal output to keep the current constant. The field generated was monitored using a 10 turn coil connected to an oscilloscope. The oscilloscope reading indicated that the field strength was the same at all frequencies tested. To determine if there was a correspondence between the signals detected by a fluxgate magnetometer (FGM1) and the Toftness Sensometer both devices were placed in the Merritt coil and readings were recorded from the FGM1 and compared with the ability of a highly experienced Toftness operator to detect the 50 ?T field. Subsequently, in a clinical setting, FGM1 readings made by an FGM1 technician and Sensometer readings were made by 4 Toftness Sensometer operators, having various degrees of experience with this device. Each examiner obtained instrument readings from 5 different volunteers in separate chiropractic adjusting rooms. Additionally, one of the Toftness Sensometers was equipped with an integrated fluxgate magnetometer (FGM2) and this magnetometer was used to obtain a second set of EMF readings in the clinical setting. Results The triaxial fluxgate magnetometer was determined to be moderately responsive to changes in magnetic field frequency below 10 Hz. At frequencies above 10 Hz the readings corresponded to that of the ambient static geofield. The practitioner operating the Toftness Sensometer was unable to detect magnetic fields at high frequencies (above 10 Hz) even at very high EMFs. The fluxgate magnetometer was shown to be essentially a DC/static magnetic field detector and like all such devices it has a limited frequency range with some low level of sensitivity at very low field frequencies. The interexaminer reliability of four Toftness practitioners using the Sensometer on 5 patients showed low to moderate correlation. Conclusions The fluxgate magnetometer although highly sensitive to static (DC) EMFs has only limited sensitivity to EMFs in the range of 1 to 10 Hz and is very insensitive to frequencies above 10 Hz. In laboratory comparisons of the Sensometer and the fluxgate magnetometer there was an occasional correspondence between the two instruments in detecting magnetic fields within the Merritt coil but these occasions were not reproducible. In the clinical studies there was low to moderate agreement between the clinicians using the Sensometer to diagnosing spinal conditions and there was little if any agreement between the Sensometer and the fluxgate magnetometer in detecting EMFs emanating from the volunteers body surface. PMID:17549105

Zhang, John; Toftness, Dave; Snyder, Brian; Nosco, Dennis; Balcavage, Walter; Nindl, Gabi

2004-01-01

63

The impact of background radiation, illumination and temperature on EMF-induced changes of aqua medium properties.  

PubMed

The effects of extremely low frequency electromagnetic field (ELF EMF) on physicochemical properties of physiological solution at different environmental media were studied. The existence of frequency "windows" at 4 and 8 Hz frequencies of ELF EMF having effects on heat fusion period, hydrogen peroxide (H2O2) formation and oxygen (O2) content of water solution and different dependency on temperature, background radiation and illumination was shown. Obtained data allow us to suggest that EMF-induced effect on water physicochemical properties depends on abovementioned environmental factors. As cell bathing medium is a target for biological effects of ELF EMF, the variability of experimental data on biological effects of EMF, obtained in different laboratories, can be explained by different environmental conditions of experiments, which very often are not considered adequately. PMID:23323624

Naira, Baghdasaryan; Yerazik, Mikayelyan; Anna, Nikoghosyan; Sinerik, Ayrapetyan

2013-09-01

64

Computing Solar Absolute Fluxes  

E-print Network

Computed color indices and spectral shapes for individual stars are routinely compared with observations for essentially all spectral types, but absolute fluxes are rarely tested. We can confront observed irradiances with the predictions from model atmospheres for a few stars with accurate angular diameter measurements, notably the Sun. Previous calculations have been hampered by inconsistencies and the use of outdated atomic data and abundances. I provide here a progress report on our current efforts to compute absolute fluxes for solar model photospheres. Uncertainties in the solar composition constitute a significant source of error in computing solar radiative fluxes.

Carlos Allende Prieto

2007-09-14

65

Osteogenic differentiation of bone mesenchymal stem cells regulated by osteoblasts under EMF exposure in a co-culture system.  

PubMed

This study examined the osteogenic effect of electromagnetic fields (EMF) under the simulated in vivo conditions. Rat bone marrow mesenchymal stem cells (BMSCs) and rat osteoblasts were co-cultured and exposed to 50 Hz, 1.0 mT EMF for different terms. Unexposed single-cultured BMSCs and osteoblasts were set as controls. Cell proliferation features of single-cultured BMSCs and osteoblasts were studied by using a cell counting kit (CCK-8). For the co-culture system, cells in each group were randomly chosen for alkaline phosphatase (ALP) staining on the day 7. When EMF exposure lasted for 14 days, dishes in each group were randomly chosen for total RNA extraction and von Kossa staining. The mRNA expression of osteogenic markers was detected by using real-time PCR. Our study showed that short-term EMF exposure (2 h/day) could obviously promote proliferation of BMSCs and osteoblasts, while long-term EMF (8 h/day) could promote osteogenic differentiation significantly under co-cultured conditions. Under EMF exposure, osteogenesis-related mRNA expression changed obviously in co-cultured and single-cultured cells. It was noteworthy that most osteogenic indices in osteoblasts were increased markedly after co-culture except Bmp2, which was increased gradually when cells were exposed to EMF. Compared to other indices, the expression of Bmp2 in BMSCs was increased sharply in both single-cultured and co-cultured groups when they were exposed to EMF. The mRNA expression of Bmp2 in BMSCs was approximately four times higher in 8-h EMF group than that in the unexposed group. Our results suggest that Bmp2-mediated cellular interaction induced by EMF exposure might play an important role in the osteogenic differentiation of BMSCs. PMID:24710940

Yu, Ji-zhe; Wu, Hua; Yang, Yong; Liu, Chao-xu; Liu, Yang; Song, Ming-yu

2014-04-01

66

Universal "Imaginary Closed Circuit Method" and Formula for Determination of Direction of Induced EMF/Current  

ERIC Educational Resources Information Center

Fleming's right-hand rule and the right-flat-hand rule are generally applied for determining the direction of flow of induced emf/current in straight conductors. The right-hand-fingers rule is applied for coils only. The right-hand-thumb rule can be applied for either straight conductors or coils. Different rules have to be applied for different…

Atram, Dattatraya Balaram

2011-01-01

67

SCHEME FOR INCORPORATING DC MAGNETIC FIELDS INTO EPIDEMIOLOGICAL STUDIES OF EMF EXPOSURE  

EPA Science Inventory

Experimental data on calcium-ion release in chicken brain tissue suggest that biological effects of electric and magnetic fields (EMFs) are concentrated at certain combinations of DC magnetic field strength and "critical" AC magnetic field frequencies. e hypothesize that "active"...

68

The role of renewable energy in climate stabilization: results from the EMF27  

E-print Network

The role of renewable energy in climate stabilization: results from the EMF27 scenarios Gunnar the role of renewable energy in climate change mitigation. Renewables currently supply approximately 18 insights emerge, the results for renewable energy deployment levels vary significantly across the models

Paris-Sud XI, Université de

69

Analysis and Optimization of Back EMF Waveform of a Flux-Switching Permanent Magnet Motor  

Microsoft Academic Search

Flux-switching permanent magnet (FSPM) motors have a doubly salient structure, the magnets being housed in the stator and the stator winding comprising concentrated coils. They have attracted considerable interest due to their essentially sinusoidal phase back electromotive force (EMF) waveform. However, to date, the inherent nature of this desirable feature has not been investigated in detail. Thus, a typical three-phase

Wei Hua; Ming Cheng; Z. Q. Zhu; David Howe

2008-01-01

70

Relative and Absolute Directions  

NSDL National Science Digital Library

The purpose of this resource is to learn about latitude and longitude while developing math skills. Students begin by asking the simple question: 'Where Am I?' Then they learn about the magnetic Earth and the use of compasses and angles. Students also learn about the difference between relative and absolute locations. Throughout this activity, students practice using a variety of math skills.

The GLOBE Program, University Corporation for Atmospheric Research (UCAR)

2003-08-01

71

ABSOLUTE WAARHEID EN TRANSCENDENTIE  

Microsoft Academic Search

The debate about the relation between science and truth is manifestly epistemological, but latently and fundamentally metaphysical. Popper's theory of verisimilitude provides us with a striking example. According to Popper, science aims at bringing us nearer to 'absolute, objective truth'; the growth of scientific knowledge is seen as a never ending realisation of that ultimate aim. This thesis of verisimilitude

A. BURMS

1982-01-01

72

Absolute ultraviolet stellar fluxes  

NASA Technical Reports Server (NTRS)

A study, made to calibrate the ultraviolet spectra of stars to within an absolute accuracy of 10%, is summarized. Data were taken by a 13 inch UVR telescope onboard several rocket flights. Calibrated and existing ground based data are in reasonable agreement. Calibrated results are presented in graphical form.

Evans, D. C.

1972-01-01

73

Absolute beam brightness detector  

SciTech Connect

In generally accepted emittance measurement, main attention is concentrated on emittance areas {epsilon}{sub x}, {epsilon}{sub y} occupied by desired part of ion beam in transverse phase space and shape of these areas. The absolute beam phase density (brightness) as usually is not measured directly and the average beam brightness B is calculated from a beam intensity I and the transverse emittances. In the ion source and low energy beam transport (LEBT) optimization, it is important to preserve the beam brightness because some aberration of ion optic and beam instabilities can decrease the brightness of the central part of ion beam significantly. For these brightness measurements, it is convenient to use an absolute beam brightness detector with the brightness determination from one short considered in this article.

Dudnikov, Vadim [Muons, Inc., Batavia, Illinois 60510 (United States)

2012-02-15

74

Supernova Absolute Magnitude Distributions  

Microsoft Academic Search

We have extended the 1990 study of supernova absolute-magnitude distributions by Miller and Branch. Supernova apparent magnitudes are taken from an updated version of the Asiago Supernova Catalog. Where possible, distances are based on Cepheid variables in the SN parent galaxy or a galaxy in the same group; otherwise re-scaled distances from the Nearby Galaxies Catalog, or Hubble-Law distances (for

D. Richardson; D. Branch; D. Casebeer; J. Deaton; E. Baron

1996-01-01

75

Application of EMF emission measurement techniques to wireless communications systems for compliance with directive 2004/40/EC.  

PubMed

Europe is the only region in the world with common legislative acts regulating exposure to electromagnetic fields (EMF) for both the general public and workers. Council Recommendation 1999/519/EC deals with the limitation of exposure of the general public to EMF (0 Hz-300 GHz). Directive 2004/40/EC regulates the minimum health and safety requirements regarding the exposure of workers to the risks arising from EMF. This paper discusses the general application of existing standards and recommendations in measurement techniques for determining compliance of measured exposure limit values and action values with those defined in 2004/40/EC. PMID:16790175

Simuni?, Dina; Gajsek, Peter

2006-01-01

76

DIRECT OBSERVATION OF THE TURBULENT emf AND TRANSPORT OF MAGNETIC FIELD IN A LIQUID SODIUM EXPERIMENT  

SciTech Connect

For the first time, we have directly measured the transport of a vector magnetic field by isotropic turbulence in a high Reynolds number liquid metal flow. In analogy with direct measurements of the turbulent Reynolds stress (turbulent viscosity) that governs momentum transport, we have measured the turbulent electromotive force (emf) by simultaneously measuring three components of velocity and magnetic fields, and computed the correlations that lead to mean-field current generation. Furthermore, we show that this turbulent emf tends to oppose and cancel out the local current, acting to increase the effective resistivity of the medium, i.e., it acts as an enhanced magnetic diffusivity. This has important implications for turbulent transport in astrophysical objects, particularly in dynamos and accretion disks.

Rahbarnia, Kian; Brown, Benjamin P.; Clark, Mike M.; Kaplan, Elliot J.; Nornberg, Mark D.; Rasmus, Alex M.; Taylor, Nicholas Zane; Forest, Cary B. [Department of Physics, University of Wisconsin-Madison, 1150 University Ave, Madison, WI 53706 (United States); Jenko, Frank; Limone, Angelo [Max-Planck-Institut fuer Plasmaphysik (IPP), EURATOM Association, D-85748 Garching (Germany); Pinton, Jean-Francois; Plihon, Nicolas; Verhille, Gautier, E-mail: kian.rahbarnia@ipp.mpg.de [Laboratoire de Physique de l'Ecole Normale Superieure de Lyon, CNRS and Universite de Lyon, F-69364 Lyon (France)

2012-11-10

77

Absolute configuration of odorine  

PubMed Central

The title compound, known as odorine or roxburghiline {systematic name: (S)-N-[(R)-1-cinnamoylpyrrolidin-2-yl]-2-methyl­butanamide}, C18H24N2O2, is a nitro­genous compound isolated from the leaves of Aglaia odorata. The absolute configuration was determined by refinement of the Flack parameter with data collected using Cu K? radiation showing positions 2 and 2? to be S and R, respectively. The pyrrolidine ring adopts an envelope conformation. In the crystal, mol­ecules are linked into chains along [010] by inter­molecular N—H?O hydrogen bonds. PMID:21588760

Fun, Hoong-Kun; Chantrapromma, Suchada; Yodsaoue, Orapun; Karalai, Chatchanok

2010-01-01

78

Effect of ELF-EMF Exposure on Human Neuroblastoma Cell Line: a Proteomics Analysis  

PubMed Central

Background Extremely low frequency electromagnetic fields (ELF-EMF) have been common in daily life all over the world. They have produced by power lines and electrical appliances, but higher levels of them have raised a lot of concerns about their carcinogenesis. Both epidemiological and laboratory studies have suggested that EMFs might increase cancer incidence, including acute childhood leukemia, brain and breast cancer. Methods In the present study, SH-SY5Y human neuroblastoma cell line has exposed to 2mT, 50 Hz magnetic field for 3 h. Next, effect of this exposure on protein expression including over-expression or under-expression has assessed by proteomics. Results Bioinformatics and statistical analysis using progenesis same spot software on the obtained 2D electrophoresis has shown that expression of 189 proteins in exposed group has changed relative to control. Besides, PCA analysis has verified results of clustering, and has shown that protein data has clustered according to experimental conditions. Conclusion The results of this study have shown that ELF-EMF changes cell morphology via altering protein expression, but more profound studies have needed to determine the kind of proteins altered. PMID:25250144

Hasanzadeh, Hadi; Rezaie-Tavirani, Mostafa; Seyyedi, Samaneh Sadat; Zali, Hakimeh; Heydari Keshel, Saeid; Jadidi, Majid; Abedelahi, Ali

2014-01-01

79

Absolute-structure reports.  

PubMed

All the 139 noncentrosymmetric crystal structures published in Acta Crystallographica Section C between January 2011 and November 2012 inclusive have been used as the basis of a detailed study of the reporting of absolute structure. These structure determinations cover a wide range of space groups, chemical composition and resonant-scattering contribution. Defining A and D as the average and difference of the intensities of Friedel opposites, their level of fit has been examined using 2AD and selected-D plots. It was found, regardless of the expected resonant-scattering contribution to Friedel opposites, that the Friedel-difference intensities are often dominated by random uncertainty and systematic error. An analysis of data collection strategy is provided. It is found that crystal-structure determinations resulting in a Flack parameter close to 0.5 may not necessarily be from crystals twinned by inversion. Friedifstat is shown to be a robust estimator of the resonant-scattering contribution to Friedel opposites, very little affected by the particular space group of a structure nor by the occupation of special positions. There is considerable confusion in the text of papers presenting achiral noncentrosymmetric crystal structures. Recommendations are provided for the optimal way of treating noncentrosymmetric crystal structures for which the experimenter has no interest in determining the absolute structure. PMID:23907862

Flack, Howard D

2013-08-01

80

The information as Absolute  

E-print Network

This article presents and grounds (i.e. presents proof of the existence, the truth, the self-consistence and the completeness of)the informational conception ("the Information as Absolute" conception)in physics and philosophy. the conception defines the information as an ultimately common, real and fundamental concept/phenomenon - "Absolute", which exists as anabsolutely infinite set ("Information" Set) of elements (members) and informational (e.g., logical) linksbetween the elements; where any element itself is some informational structure also. Correspondingly, for example, Matter as the substence, radiation, etc., is some development or realization of informational patterns, constituting a specific - and practically infinitesimal comparing to the Set - subset of the "Information" Set. The conception allows for the resolution, or at least for a consideration on a higher level of comprehension, of the basic ontological and epistemological problems in philosophy and natural sciences; in physics it allows to suggest reasonable model, which makes more clear basic phisical notions,such as space, time, matter, etc.

Sergey V. Shevchenko; Vladimir V. Tokarevsky

2010-04-20

81

ABSOLUTE POLARIMETRY AT RHIC.  

SciTech Connect

Precise and absolute beam polarization measurements are critical for the RHIC spin physics program. Because all experimental spin-dependent results are normalized by beam polarization, the normalization uncertainty contributes directly to final physics uncertainties. We aimed to perform the beam polarization measurement to an accuracy Of {Delta}P{sub beam}/P{sub beam} < 5%. The absolute polarimeter consists of Polarized Atomic Hydrogen Gas Jet Target and left-right pairs of silicon strip detectors and was installed in the RHIC-ring in 2004. This system features proton-proton elastic scattering in the Coulomb nuclear interference (CNI) region. Precise measurements of the analyzing power A{sub N} of this process has allowed us to achieve {Delta}P{sub beam}/P{sub beam} = 4.2% in 2005 for the first long spin-physics run. In this report, we describe the entire set up and performance of the system. The procedure of beam polarization measurement and analysis results from 2004-2005 are described. Physics topics of AN in the CNI region (four-momentum transfer squared 0.001 < -t < 0.032 (GeV/c){sup 2}) are also discussed. We point out the current issues and expected optimum accuracy in 2006 and the future.

OKADA; BRAVAR, A.; BUNCE, G.; GILL, R.; HUANG, H.; MAKDISI, Y.; NASS, A.; WOOD, J.; ZELENSKI, Z.; ET AL.

2007-09-10

82

Sensorless inverter-fed compressor drive system using saliency back-EMF based intelligent torque observer with MTPA control  

Microsoft Academic Search

A saliency back-EMF based wavelet fuzzy neural network (WFNN) torque observer using a new maximum torque per ampere (MTPA) control is proposed in this study to improve the speed estimating performance of a sensorless interior permanent magnet synchronous motor (IPMSM) drive system. First, the characteristics and mathematical model of the saliency back-EMF based proportional-integral-derivative (PID) torque observer with the mechanical

Faa-Jeng Lin

2014-01-01

83

Absolute radiometric code (ARC)  

NASA Astrophysics Data System (ADS)

The Absolute Radiometric Code (ARC) is a collection of Matlab functions tied together under a Matlab Graphical User Interface (GUI). ARC was developed as part of the Satellite Imaging Experiment conducted by the Air Force Research Laboratory at Kirtland, AFB, in order to get fast estimates of the Optical Cross Sections of various satellites. ARC uses multiple star measures to calculate the atmospheric and optical transmission of the system. The transmissions are then used to compute the optical cross section of an object. Generally, the optical transmission of a sensor system can be characterized quite well, so it serves as a sanity check on all ARC results. The atmospheric transmission changes considerably from night to night and even from hour to hour on the same night. ARC uses a collection of calibration stars at various elevation angles to determine the atmospheric transmission through the viewing times. The star calibration is generally taken several times during the experiment period.

Riker, James F.; Roark, Jon; Stogsdill, Stephen E.; DeShetler, W. Bruce; Brunson, Richard L.

1999-08-01

84

Absolute Equilibrium Entropy  

NASA Technical Reports Server (NTRS)

The entropy associated with absolute equilibrium ensemble theories of ideal, homogeneous, fluid and magneto-fluid turbulence is discussed and the three-dimensional fluid case is examined in detail. A sigma-function is defined, whose minimum value with respect to global parameters is the entropy. A comparison is made between the use of global functions sigma and phase functions H (associated with the development of various H-theorems of ideal turbulence). It is shown that the two approaches are complimentary though conceptually different: H-theorems show that an isolated system tends to equilibrium while sigma-functions allow the demonstration that entropy never decreases when two previously isolated systems are combined. This provides a more complete picture of entropy in the statistical mechanics of ideal fluids.

Shebalin, John V.

1997-01-01

85

Optical tweezers absolute calibration  

E-print Network

Optical tweezers are highly versatile laser traps for neutral microparticles, with fundamental applications in physics and in single molecule cell biology. Force measurements are performed by converting the stiffness response to displacement of trapped transparent microspheres, employed as force transducers. Usually, calibration is indirect, by comparison with fluid drag forces. This can lead to discrepancies by sizable factors. Progress achieved in a program aiming at absolute calibration, conducted over the past fifteen years, is briefly reviewed. Here we overcome its last major obstacle, a theoretical overestimation of the peak stiffness, within the most employed range for applications, and we perform experimental validation. The discrepancy is traced to the effect of primary aberrations of the optical system, which are now included in the theory. All required experimental parameters are readily accessible. Astigmatism, the dominant effect, is measured by analyzing reflected images of the focused laser spo...

Dutra, R S; Neto, P A Maia; Nussenzveig, H M

2014-01-01

86

Absolute neutrino mass measurements  

SciTech Connect

The neutrino mass plays an important role in particle physics, astrophysics and cosmology. In recent years the detection of neutrino flavour oscillations proved that neutrinos carry mass. However, oscillation experiments are only sensitive to the mass-squared difference of the mass eigenvalues. In contrast to cosmological observations and neutrino-less double beta decay (0v2{beta}) searches, single {beta}-decay experiments provide a direct, model-independent way to determine the absolute neutrino mass by measuring the energy spectrum of decay electrons at the endpoint region with high accuracy.Currently the best kinematic upper limits on the neutrino mass of 2.2eV have been set by two experiments in Mainz and Troitsk, using tritium as beta emitter. The next generation tritium {beta}-experiment KATRIN is currently under construction in Karlsruhe/Germany by an international collaboration. KATRIN intends to improve the sensitivity by one order of magnitude to 0.2eV. The investigation of a second isotope ({sup 137}Rh) is being pursued by the international MARE collaboration using micro-calorimeters to measure the beta spectrum. The technology needed to reach 0.2eV sensitivity is still in the R and D phase. This paper reviews the present status of neutrino-mass measurements with cosmological data, 0v2{beta} decay and single {beta}-decay.

Wolf, Joachim [Karlsruhe Institute of Technology (KIT), IEKP, Postfach 3640, 76021 Karlsruhe (Germany)

2011-10-06

87

Absolute Zero: Science Educator's Guide  

NSDL National Science Digital Library

This guide provides recommendations for curricular modules on low temperature physics. Designed for teachers and informal educators of middle school students. this guide complements the Absolute Zero Community Education Outreach Guide. Suggestions on leading discussions, increasing student participation, and the use of inquiry are included. This material is related to a two-part public broadcasting special, Absolute Zero, produced by Meridian Productions and Windfall Films. Absolute Zero is underwritten by the National Science Foundation and the Alfred P. Sloan Foundation and is based largely on Tom Shachtmanâs acclaimed book, Absolute Zero and the Conquest of Cold.

2008-09-18

88

The electric and magnetic fields research and public information dissemination (EMF-RAPID) program.  

PubMed

In the United States, public concern that exposure to power-line fields was linked to cancer led to the establishment of a Congressionally mandated program, the Electric and Magnetic Fields Research and Public Information Dissemination (EMF-RAPID) Program. A major goal of the program was to "determine whether or not exposures to electric and magnetic fields produced by the generation, transmission, and use of electrical energy affect human health". Between 1994 and 1998, the EMF-RAPID program spent approximately $41 million on biological research. Much of the work funded by the EMF-RAPID program has not yet been published in the peer-reviewed literature. The U.S. National Institute of Environmental Health Sciences (NIEHS) asked that Radiation Research publish this special issue in an attempt to remedy this publication gap. The issue includes reviews of studies that were done to assess the biological plausibility of claims that power-frequency fields caused leukemia and breast cancer. The issue continues with two teratology studies and one immunology study. The section of the issue covering in vitro studies begins with an overview of the efforts NIEHS made to replicate a wide range of reported effects of power-frequency fields and continues with four papers reporting the absence of effects of power-frequency fields on the expression of stress-response genes and oncogenes. Other reports of in vitro studies and studies of mechanisms cover cytotoxicity, gap junction intracellular communication, calcium ion transport across the plasma membrane, and intracellular electric fields. PMID:10790283

Moulder, J E

2000-05-01

89

Safety of high speed guided ground transportation systems. Broadband magnetic fields: Their possible role in EMF-associated bioeffects. Final report, January 1993-June 1993  

SciTech Connect

The report reviews electric and magnetic field (EMF) exposures from electrical transportation systems, including electrically powered rail and magnetic levitation (maglev). Material also covered includes research concerning biological effects of EMF exposure, with special emphasis on broad spectrum or broadband magnetic fields. A primary objective of the report was to consider, based on present knowledge, the potential for adverse health effects from maglev-associated EMF. Because maglev technology is known to generate magnetic fields at a variety of frequencies, the document addresses the broadband EMF frequency characteristics (including pulses, intermittent fields, and other transient phenomena).

Goellner, D.; Wilson, B.; Reiter, R.; Pilla, A.; Hankin, N.

1993-08-01

90

Photo-EMF Sensitivity of Porous Silicon Thin Layer-Crystalline Silicon Heterojunction to Ammonia Adsorption  

PubMed Central

A new method of using photo-electromotive force in detecting gas and controlling sensitivity is proposed. Photo-electromotive force on the heterojunction between porous silicon thin layer and crystalline silicon wafer depends on the concentration of ammonia in the measurement chamber. A porous silicon thin layer was formed by electrochemical etching on p-type silicon wafer. A gas and light transparent electrical contact was manufactured to this porous layer. Photo-EMF sensitivity corresponding to ammonia concentration in the range from 10 ppm to 1,000 ppm can be maximized by controlling the intensity of illumination light. PMID:22319353

Vashpanov, Yuriy; Jung, Jae Il; Kwack, Kae Dal

2011-01-01

91

Photo-EMF sensitivity of porous silicon thin layer-crystalline silicon heterojunction to ammonia adsorption.  

PubMed

A new method of using photo-electromotive force in detecting gas and controlling sensitivity is proposed. Photo-electromotive force on the heterojunction between porous silicon thin layer and crystalline silicon wafer depends on the concentration of ammonia in the measurement chamber. A porous silicon thin layer was formed by electrochemical etching on p-type silicon wafer. A gas and light transparent electrical contact was manufactured to this porous layer. Photo-EMF sensitivity corresponding to ammonia concentration in the range from 10 ppm to 1,000 ppm can be maximized by controlling the intensity of illumination light. PMID:22319353

Vashpanov, Yuriy; Jung, Jae Il; Kwack, Kae Dal

2011-01-01

92

Higher order concentration moments collapse in the expected mass fraction (EMF) based risk assessment  

NASA Astrophysics Data System (ADS)

In this work Langrangian framework is used for conservative tracer transport simulations through 2-D extremely heterogeneous porous media. Conducted numerical simulations enable large sets of concentration values in both spatial and temporal domains. In addition to the advection, which acts on all scales, an additional mechanism considered is local scale dispersion (LSD), accounting for both mechanical dispersion and molecular diffusion. The ratio between these two mechanisms is quantified by the Peclet (Pe) number. In its base, the work gives answers to concentration scalar features when influenced by: i) different log-conductivity variance; ii) log-conductivity structures defined by the same global variogram but with different log conductivity patterns correlated; and iii) for a wide range of Peclet values. Results conducted by Monte Carlo analysis show a complex interplay between the aforementioned parameters, indicating the influence of aquifer properties to temporal LSD evolution. A remarkable collapse of higher order to second-order concentration moments [Yee, 2009] leads to the conclusion that only two concentration moments are required for an accurate description of concentration fluctuations. This explicitly holds for the pure advection case, while in the case of LSD presence the moment deriving function(MDF) is involved to ensure the moment collapse validity. An inspection of the Beta distribution leads to the conclusion that the two-parametric distribution can be used for concentration fluctuation characterization even in cases of high aquifer heterogeneity and/or for different log-conductivity structures, independent of the sampling volume used. Furthermore, the expected mass fraction (EMF) [Heagy & Sullivan, 1996] concept is applied in groundwater transport. In its origin, EMF is function of the concentration but with lower number of realizations needed for its determination, compared to the one point PDF. From practical point of view, EMF excludes meandering effect and incorporates information about exposure time for each non-zero concentration value present. Also, it is shown that EMF is able to clearly reflect the effects of aquifer heterogeneity and structure as well as the Pe value. The latter is demonstrated through the non-carcinogenic risk assessment framework. To demonstrate the uniqueness of the moment collapse feature and ability of the Beta distribution to account for the concentration frequencies even in real cases, Macrodispersion Experiment (MADE1) [Boggs et al, 1992] data sets are used for validation.

Srzic, Veljko; Gotovac, Hrvoje; Cvetkovic, Vladimir; Andricevic, Roko

2014-05-01

93

Supernova absolute-magnitude distributions  

Microsoft Academic Search

The Asiago Supernova Catalogue and the Nearby Galaxies Catalog are used to study the absolute-magnitude distributions of supernovae. SNe Ia that appear to be subluminous are in highly inclined disk galaxies, which implies that the apparent dispersion in SN Ia absolute magnitudes is dominated by interstellar extinction in the parent galaxies, and, thus, that SNe Ia are good intrinsic standard

Douglas L. Miller; David Branch

1990-01-01

94

Absolute and Relative Grading Standards.  

ERIC Educational Resources Information Center

K. K. Waltman and D. A. Frisbie (1994) observed that teachers and parents often interpret grades given to students in both absolute and relative senses. They conclude that this sort of interpretation is illogical and may indicate misunderstandings in several areas. Absolute and relative methods of assigning letter grades are approached from…

Johanson, George A.

95

Equilibrium vacancy concentrations in copper investigated with the absolute technique  

Microsoft Academic Search

The molar fraction of thermally generated vacant lattice sites Nv has been measured during thermal equilibrium up to temperatures near the melting point in 99.9998%-grade copper with an absolute technique. A high-resolution differential dilatometric experiment is performed. The thermal expansion of the lattice Deltaa(T)\\/a0 is determined by the Debye-Scherrer technique. The macroscopic expansion DeltaL(T)\\/L0 is measured with a special laser

Th. Hehenkamp; W. Berger; J.-E. Kluin; Ch. Lüdecke; J. Wolff

1992-01-01

96

Effects of 940 MHz EMF on bioluminescence and oxidative response of stable luciferase producing HEK cells.  

PubMed

The effects of mobile phone frequency electromagnetic field (RF-EMF, 940 MHz) on a stable cell line (HEK293T) harbouring the firefly luciferase gene were evaluated. A waveguide exposure system with 1 W input power provided the mean specific absorption rate of ?0.09 W kg(-1) in 35 mm Petri dishes. The effects of exposure duration (15, 30, 45, 60 and 90 min) on luciferase activity and oxidative response elements were investigated. Endogenous luciferase activity was reduced after 30 and 45 min of continuous exposure, while after 60 min, the exposed cell lysate showed higher luciferase activity compared with the non-exposed control. Reactive oxygen species (ROS) generation was highest in the 30 min exposed cells as studied by 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) fluorescence. The observed boost in ROS was then followed by a sharp rise in catalase (CAT) and superoxide dismutase (SOD) activity and elevation of glutathione (GSH) during the 45 min exposure. Decrease in lipid peroxidation (malondialdehyde, MDA) was meaningful for the 45 and 60 min exposed cells. Therefore, it appears that an increase in the activity of luciferase after 60 min of continuous exposure could be associated with a decrease in ROS level caused by activation of the oxidative response. This ability in cells to overcome oxidative stress and compensate the luciferase activity could also be responsible for the adaptive response mechanism detected in ionizing radiation studies with RF-EMF pre-treatments. PMID:24886806

Sefidbakht, Yahya; Moosavi-Movahedi, Ali Akbar; Hosseinkhani, Saman; Khodagholi, Fariba; Torkzadeh-Mahani, Masoud; Foolad, Forough; Faraji-Dana, Reza

2014-07-01

97

Standard Gibbs energy of formation of Mo 3Te 4 by emf measurements  

NASA Astrophysics Data System (ADS)

The emf of the galvanic cells Pt, Mo, MoO 2¦8 YSZ¦'FeO', Fe, Pt (I) and Pt, Fe,'FeO' ¦8 YSZ¦MoO 2, Mo 3Te 4, MoTe 2(?), C, Pt (II) were measured over the temperature ranges 837 to 1151 K and 775 to 1196 K, respectively, using 8 mass% yttria-stabilized zirconia (8 YSZ) as the solid electrolyte. From the emf values, the partial molar Gibbs energy of solution of molybdenum in Mo 3Te 4/MoTe 2(?), ? ?Mo was found to be ? ?Mo ± 1.19 ( kJ/mol) = -025.08 + 0.00420T(K) . Using the literature data for the Gibbs energy of formation of MoTe 2(?). the expression ?G° f( Mo3Te4, s) ± 5.97 (kj/mol) = -253.58 + 0.09214 T( K) was derived for the range 775 to 1196 K. A third-law analysis yielded a value of -209 ± 10 kJ/mol for ?H° f.298o of Mo 3Te 4(s).

Mallika, C.; Sreedharan, O. M.

1990-03-01

98

Absolute stereochemistry of anisodorin 5  

Microsoft Academic Search

The absolute stereochemistry of the natural diterpene anisodorin 5 1, previously isolated from the marine dorid nudibranch Anisodoris fontaini, has been established by synthesis of its enantiomer ent-anisodorin 5 3.

Nicon Ungur; Margherita Gavagnin; Ernesto Mollo; Guido Cimino

1999-01-01

99

Assessment of the neurotoxic potential of exposure to 50Hz extremely low frequency electromagnetic fields (ELF-EMF) in naïve and chemically stressed PC12 cells.  

PubMed

Increasing exposure to extremely low frequency electromagnetic fields (ELF-EMF), generated by power lines and electric appliances, raises concern about potential adverse health effects of ELF-EMF. The central nervous system is expected to be particularly vulnerable to ELF-EMF as its function strongly depends on electrical excitability. We therefore investigated effects of acute (30min) and sub-chronic (48h) exposure to 50Hz ELF-EMF on naïve and chemically stressed pheochromocytoma (PC12) cells. The latter have higher levels of iron and/or reactive oxygen species (ROS) and display increased vulnerability to environmental insults. Effects of ELF-EMF on Ca(2+)-homeostasis, ROS production and membrane integrity were assessed using Fura-2 single cell fluorescence microscopy, H2-DCFDA and CFDA assays, respectively. Our data demonstrate that acute exposure of naïve PC12 cells to 50Hz ELF-EMF up to 1000?T fails to affect basal or depolarization-evoked [Ca(2+)]i. Moreover, sub-chronic ELF-EMF exposure up to 1000?T has no consistent effects on Ca(2+)-homeostasis in naïve PC12 cells and does not affect ROS production and membrane integrity. Notably, in chemically stressed PC12 cells both acute and sub-chronic ELF-EMF exposure also failed to exert consistent effects on Ca(2+)-homeostasis, ROS production and membrane integrity. Our combined findings thus indicate that exposure to 50Hz ELF-EMF up to 1000?T, i.e. 10,000 times above background exposure, does not induce neurotoxic effects in vitro, neither in naïve nor in chemically stressed PC12 cells. Though our data require confirmation, e.g. in developing neuronal cells in vitro or (developing) animals, it appears that the neurotoxic risk of ELF-EMF exposure is limited. PMID:25111744

de Groot, Martje W G D M; Kock, Marjolijn D M; Westerink, Remco H S

2014-09-01

100

EHS subjects do not perceive RF EMF emitted from smart phones better than non-EHS subjects.  

PubMed

As the use of smart phones increases, social concerns have arisen concerning the possible effects of radio frequency-electromagnetic fields (RF-EMFs) emitted from wideband code division multiple access (WCDMA) mobile phones on human health. The number of people with self-reported electromagnetic hypersensitivity (EHS) who complain of various subjective symptoms, such as headache, insomnia, etc., has also recently increased. However, it is unclear whether EHS subjects can detect RF-EMFs exposure or not. In this double-blind study, two volunteer groups of 17 EHS and 20 non-EHS subjects were investigated in regards to their perception of RF-EMFs with real and sham exposure sessions. Experiments were conducted using a WCDMA module inside a dummy phone with an average power of 24 dBm at 1950 MHz and a specific absorption rate of 1.57 W/kg using a dummy headphone for 32 min. In conclusion, there was no indication that EHS subjects perceive RF-EMFs better than non-EHS subjects. PMID:23366357

Kwon, Min Kyung; Kim, Sung Kean; Koo, Jeong Mo; Choi, Joon Yul; Kim, Deok Won

2012-01-01

101

Speed control of permanent magnet motors using sliding mode observers for induced EMF position and speed estimation  

Microsoft Academic Search

This paper presents a speed control system for a permanent magnet synchronous motor (PMSM) in which the sliding mode technique is used to estimate the induced EMF, rotor position and speed. The electrical dynamic equations of PMSM are modified to obtain the sliding mode observer model and then the variables are estimated by using only measured stator currents and voltages.

Zelia M. A. Peixoto; Flavia M. F. Sa; P. F. Seixas; Benjamin R. Menezes; Porfirio C. Cortizo

1995-01-01

102

Environmental Pathology: SY09-2 MULTIPLE SCLEROSIS (MS) AND NEURODEGENERATION: CAUSE AND PATHOGENESIS IN RELATION TO ELECTROMAGNETIC FIELDS (EMF).  

PubMed

Multiple sclerosis (MS) is prevalent in higher latitude areas where geomagnetic storms often occur. The earliest pathological finding is myelin destruction. Myelin is a high capacitance electrolytic capacitor that can store a large amount of charge and energy. Since storms possess high-energy electromagnetic fields (EMF), the capacitor will be overcharged, which may break down the dielectric. As a result, a short circuit occurs and electrolytes heat up and/or the capacitor may burst. Also, EMFs have the potential to induce hotspots in the center of the brain. The increased temperature of the cerebrospinal fluid will cause hot water burns in surrounding areas. Thus, two distinct lesions exist in MS, electric shock and hot water burns. In addition, the overcharged capacitor will produce repetitive or continuous action potentials, causing excess Ca2+ influxes and subsequent excitotoxicity. This leads to mitochondrial dysfunction, including an energy deficit, oxidative stress and apoptosis. Moreover, EMFs activate microglia via activation of voltage-gated ion channels. These MS related neurodegenerative and inflammatory processes could have causes and pathogeneses in common with Alzheimer's, Parkinson's, and amyotrophic lateral sclerosis, which are often reported in MS patients. I hypothesize thus that MS and certain common neurodegenerative diseases are caused by high energy EMF. PMID:25188068

Kudo, Motoshige

2014-10-01

103

Insights from EMF Associated Agricultural and Forestry Greenhouse Gas Mitigation Studies  

SciTech Connect

Integrated assessment modeling (IAM) as employed by the Energy Modeling Forum (EMF) generally involves a multi-sector appraisal of greenhouse gas emission (GHGE) mitigation alternatives and climate change effects typically at the global level. Such a multi-sector evaluation encompasses potential climate change effects and mitigative actions within the agricultural and forestry (AF) sectors. In comparison with many of the other sectors covered by IAM, the AF sectors may require somewhat different treatment due to their critical dependence upon spatially and temporally varying resource and climatic conditions. In particular, in large countries like the United States, forest production conditions vary dramatically across the landscape. For example, some areas in the southern US present conditions favorable to production of fast growing, heat tolerant pine species, while more northern regions often favor slower-growing hardwood and softwood species. Moreover, some lands are currently not suitable for forest production (e.g., the arid western plains). Similarly, in agriculture, the US has areas where citrus and cotton can be grown and other areas where barley and wheat are more suitable. This diversity across the landscape causes differential GHGE mitigation potential in the face of climatic changes and/or responses to policy or price incentives. It is difficult for a reasonably sized global IAM system to reflect the full range of sub-national geographic AF production possibilities alluded to above. AF response in the face of climate change altered temperature precipitation regimes or mitigation incentives will likely involve region-specific shifts in land use and agricultural/forest production. This chapter addresses AF sectoral responses in climate change mitigation analysis. Specifically, we draw upon US-based studies of AF GHGE mitigation possibilities that incorporate sub-national detail drawing largely on a body of studies done by the authors in association with EMF activities. We discuss characteristics of AF sectoral responses that could be incorporated in future IAM efforts in climate change policy.

McCarl, Bruce A.; Murray, Brian; Kim, Man-Keun; Lee, Heng-Chi; Sands, Ronald D.; Schneider, Uwe

2007-11-19

104

Supernova absolute-magnitude distributions  

SciTech Connect

The Asiago Supernova Catalogue and the Nearby Galaxies Catalog are used to study the absolute-magnitude distributions of supernovae. SNe Ia that appear to be subluminous are in highly inclined disk galaxies, which implies that the apparent dispersion in SN Ia absolute magnitudes is dominated by interstellar extinction in the parent galaxies, and, thus, that SNe Ia are good intrinsic standard candles (sigma below 0.4 mag). An upper limit to the difference between SNe Ib and SNe Ia in the B band is 1.87 mag, but the bolometric difference is smaller. Due to a large intrinsic range in peak absolute magnitude (about 6 mag), the observed sample of SNe II is severely influenced by selection effects; intrinsically faint SNe II (M/B/greater than about -17 for H0 = 75 km/s per Mpc) are much more common than intrinsically bright ones. 45 refs.

Miller, D.L.; Branch, D. (Oklahoma Univ., Norman (USA))

1990-08-01

105

Absolute fiber optic pressure transducer for aircraft air data measurement  

Microsoft Academic Search

The authors present the design rationale for a total pressure fiber optic transducer under development for planned flight test. Pressure sealing problems for absolute pressure transduction are discussed. Information is given on the microbend fiber optic sensor approach used to measure diaphragm deflection, and requirements for microbend sensor thermal compensation. Wavelength division multiplexing (WDM) approaches are described to self-reference the

S. E. Reed; J. W. Berthold

1991-01-01

106

Absolute configuration of amphidinin A.  

PubMed

The absolute configurations at six stereogenic centers in amphidinin A (1), a cytotoxic linear polyketide isolated from a symbiotic marine dinoflagellate, Amphidinium sp., were elucidated to be 2R, 4R, 6S, 9R 11R, and 12S by the combination of J-based configuration analysis, modified Mosher's method, and density-functional theory calculations. PMID:24836179

Iwai, Takahiro; Kubota, Takaaki; Kobayashi, Jun'ichi

2014-06-27

107

Absolute transition probabilities of phosphorus.  

NASA Technical Reports Server (NTRS)

Use of a gas-driven shock tube to measure the absolute strengths of 21 P I lines and 126 P II lines (from 3300 to 6900 A). Accuracy for prominent, isolated neutral and ionic lines is estimated to be 28 to 40% and 18 to 30%, respectively. The data and the corresponding theoretical predictions are examined for conformity with the sum rules.-

Miller, M. H.; Roig, R. A.; Bengtson, R. D.

1971-01-01

108

The Concept of the Absolute  

E-print Network

KU ScholarWorks | The University of Kansas Pre-1923 Dissertations and Theses Collection The Concept of the Absolute; Its Historical Development 1910 by C.O. VanDyke This work was digitized by the Scholarly Communications program staff in the KU...

Van Dyke, C. O.

1910-01-01

109

Achieving Climate Change Absolute Accuracy in Orbit  

NASA Technical Reports Server (NTRS)

The Climate Absolute Radiance and Refractivity Observatory (CLARREO) mission will provide a calibration laboratory in orbit for the purpose of accurately measuring and attributing climate change. CLARREO measurements establish new climate change benchmarks with high absolute radiometric accuracy and high statistical confidence across a wide range of essential climate variables. CLARREO's inherently high absolute accuracy will be verified and traceable on orbit to Système Internationale (SI) units. The benchmarks established by CLARREO will be critical for assessing changes in the Earth system and climate model predictive capabilities for decades into the future as society works to meet the challenge of optimizing strategies for mitigating and adapting to climate change. The CLARREO benchmarks are derived from measurements of the Earth's thermal infrared spectrum (5-50 micron), the spectrum of solar radiation reflected by the Earth and its atmosphere (320-2300 nm), and radio occultation refractivity from which accurate temperature profiles are derived. The mission has the ability to provide new spectral fingerprints of climate change, as well as to provide the first orbiting radiometer with accuracy sufficient to serve as the reference transfer standard for other space sensors, in essence serving as a "NIST [National Institute of Standards and Technology] in orbit." CLARREO will greatly improve the accuracy and relevance of a wide range of space-borne instruments for decadal climate change. Finally, CLARREO has developed new metrics and methods for determining the accuracy requirements of climate observations for a wide range of climate variables and uncertainty sources. These methods should be useful for improving our understanding of observing requirements for most climate change observations.

Wielicki, Bruce A.; Young, D. F.; Mlynczak, M. G.; Thome, K. J; Leroy, S.; Corliss, J.; Anderson, J. G.; Ao, C. O.; Bantges, R.; Best, F.; Bowman, K.; Brindley, H.; Butler, J. J.; Collins, W.; Dykema, J. A.; Doelling, D. R.; Feldman, D. R.; Fox, N.; Huang, X.; Holz, R.; Huang, Y.; Jennings, D.; Jin, Z.; Johnson, D. G.; Jucks, K.; Kato, S.; Kratz, D. P.; Liu, X.; Lukashin, C.; Mannucci, A. J.; Phojanamongkolkij, N.; Roithmayr, C. M.; Sandford, S.; Taylor, P. C.; Xiong, X.

2013-01-01

110

THERMAL SKIN DAMAGE AND MOBILE PHONE USE Elmountacer Billah Elabbassi(1)  

E-print Network

THERMAL SKIN DAMAGE AND MOBILE PHONE USE Elmountacer Billah Elabbassi(1) , René de Sèze(2) (1) above, but Email: Rene.DE-SEZE@ineris.fr ABSTRACT Mobile phone "cell phone" use has dramatically in normal use. KEYWORDS Mobile phone (MP); Electromagnetic field (EMF); Skin température; Thermal damage

Paris-Sud XI, Université de

111

Platinum versus palladium thermocouples: an emf-temperature reference function for the range 0 °C to 1500 °C  

Microsoft Academic Search

We present an emf-temperature reference function for platinum versus palladium (Pt\\/Pd) thermocouples in air for the range 0 °C to 1500 °C. The reference function is based on the International Temperature Scale of 1990 (ITS-90) and has an expanded uncertainty (coverage factor of two) of less than the equivalent of 11 mK for temperatures up to 1050 °C and rising

G W Burns; D C Ripple; M Battuello

1998-01-01

112

Report on Toyota/Prius Motor Torque-Capability, Torque-Property, No-Load Back EMF, and Mechanical Losses  

SciTech Connect

In today's hybrid vehicle market, the Toyota Prius drive system is currently considered the leader in electrical, mechanical, and manufacturing innovations. It is significant that in today's marketplace, Toyota is able to manufacture and sell the vehicle for a profit. This project's objective is to test the torque capability of the 2004 Prius motor and to analyze the torque properties relating to the rotor structure. The tested values of no-load back electromotive force (emf) and mechanical losses are also presented.

Hsu, J.S.

2004-09-30

113

Direct torque and indirect flux control of brushless DC motor with non-sinusoidal back-EMF without position sensor  

Microsoft Academic Search

In this paper, the position sensorless direct torque and indirect flux control (DTIFC) of BLDC motor with nonsinusoidal (non-ideal trapezoidal) Back-EMF has been extensively investigated using three-phase conduction scheme with six-switch inverter. In the literature, several methods have been proposed to eliminate the low-frequency torque pulsations for BLDC motor drives such as Fourier series analysis of current waveforms and either

Reza Heidari; GholamReza Arab Markadeh; Saeed Abazari

2011-01-01

114

Perturbative Transport studies of Turbulent EMFs in the Madison Dynamo Experiment  

NASA Astrophysics Data System (ADS)

Previous experiments on the MDE have demonstrated the need for a turbulent electromotive force to describe the dynamics of the magnetic field evolution. In these experiments a weak, DC external seed field---sharing the symmetry axis of the mean flow---was applied to a flowing sodium. Data modeling showed that the currents measured in the sodium could not be explained from the mean flow alone. However, the overall trend was not inconsistent with an enhanced resistivity (a beta effect). Two new experiments are underway to better characterize this turbulent EMF. First, time varying magnetic fields will be applied to perturbatively measure current transport. Second, an internal velocity probe is being developed to directly measure the correlation between magnetic and velocity fluctuations at a given location. This poster will present numerical models which study the degree to which a spatial variation in the resistivity can be determined from measured responses in a range of frequencies. A high current H-bridge amplifier has been constructed to apply 500 gauss, sinusoidal fields with frequencies up to 10 hz. The profile of the response will be measured by an internal array of 3D hall probes. This profile should provide a measure of the turbulent enhancement to resistivity, and the degree to which it is reduced by the presence of a mean magnetic field.

Kaplan, E. J.; Forest, C. B.; Kendrick, R. D.; Rasmus, A. M.; Taylor, N. Z.

2009-11-01

115

Effects of whole body exposure to extremely low frequency electromagnetic fields (ELF-EMF) on serum and liver lipid levels, in the rat  

PubMed Central

Backgound The effects of extremely low-frequency electromagnetic fields (ELF-EMF) on the blood serum and liver lipid concentrations of male Wistar rats were assessed. Methods Animals were exposed to a single stimulation (2 h) of ELF-EMF (60 Hz, 2.4 mT) or sham-stimulated and thereafter sacrificed at different times (24, 48 or 96 h after beginning the exposure). Results Blood lipids showed, at 48 h stimulated animals, a significant increase of cholesterol associated to high density lipoproteins (HDL-C) than those observed at any other studied time. Free fatty acid serum presented at 24 h significant increases in comparison with control group. The other serum lipids, triacylglycerols and total cholesterol did not show differences between groups, at any time evaluated. No statistical differences were shown on total lipids of the liver but total cholesterol was elevated at 24 h with a significant decrease at 96 h (p = 0.026). The ELF-EMF stimulation increased the liver content of lipoperoxides at 24 h. Conclusion Single exposures to ELF-EMF increases the serum values of HDL-C, the liver content of lipoperoxides and decreases total cholesterol of the liver. The mechanisms for the effects of ELF-EMF on lipid metabolism are not well understand yet, but could be associated to the nitric oxide synthase EMF-stimulation. PMID:18021407

Torres-Duran, Patricia V; Ferreira-Hermosillo, Aldo; Juarez-Oropeza, Marco A; Elias-Vinas, David; Verdugo-Diaz, Leticia

2007-01-01

116

PROJECTIVE GROUP STRUCTURES AS ABSOLUTE GALOIS STRUCTURES  

E-print Network

PROJECTIVE GROUP STRUCTURES AS ABSOLUTE GALOIS STRUCTURES of a cover to a cartesioan square . . . . . . . . . . . . . . * *. 1 4. Projective groups structures of the Main Theorem . . . . . . . . . . . . . . . . . . . . 1 14. Projective group structures as absolute

117

PROJECTIVE GROUP STRUCTURES AS ABSOLUTE GALOIS STRUCTURES  

E-print Network

PROJECTIVE GROUP STRUCTURES AS ABSOLUTE GALOIS STRUCTURES. A proper profinite group structure G is projective if and only if G* * is the absolute Galois group to a cartesian square . . . . . . . . . . . . . . . * * 19 4. Projective group structures

Pop, Florian

118

Absolute MR thermometry using nanocarriers.  

PubMed

Accurate time-resolved temperature mapping is crucial for the safe use of hyperthermia-mediated drug delivery. We here propose a magnetic resonance imaging temperature mapping method in which drug delivery systems serve not only to improve tumor targeting, but also as an accurate and absolute nano-thermometer. This method is based on the temperature-dependent chemical shift difference between water protons and the protons in different groups of drug delivery systems. We show that the chemical shift of the protons in the ethylene oxide group in polyethylene glycol (PEG) is temperature-independent, whereas the proton resonance of water decreases with increasing temperature. The frequency difference between both resonances is linear and does not depend on pH and physiological salt conditions. In addition, we show that the proton resonance of the methyl group in N-(2-hydroxypropyl)-methacrylamide (HPMA) is temperature-independent. Therefore, PEGylated liposomes, polymeric mPEG-b-pHPMAm-Lac2 micelles and HPMA copolymers can provide a temperature-independent reference frequency for absolute magnetic resonance (MR) thermometry. Subsequently, we show that multigradient echo MR imaging with PEGylated liposomes in situ allows accurate, time-resolved temperature mapping. In conclusion, nanocarrier materials may serve as highly versatile tools for tumor-targeted drug delivery, acting not only as hyperthermia-responsive drug delivery systems, but also as accurate and precise nano-thermometers. PMID:24706612

Deckers, Roel; Sprinkhuizen, Sara M; Crielaard, Bart J; Ippel, Johannes H; Boelens, Rolf; Bakker, Chris J G; Storm, Gert; Lammers, Twan; Bartels, Lambertus W

2014-01-01

119

Analysis of cell performance and thermal regeneration of a lithium-tin cell having an immobilized fused-salt electrolyte  

NASA Technical Reports Server (NTRS)

Cell performance and thermal regeneration of a thermally regenerative cell uses lithium and tin and a fused-salt electrolyte. The emf of the Li-Sn cell, as a function of cathode-alloy composition, is shown to resemble that of the Na-Bi cell.

Cairns, E. J.; Shimotake, H.

1969-01-01

120

Thermodynamic behavior of high-T sub c oxide systems via EMF and related measurements  

SciTech Connect

EMF measurements of oxygen fugacities as a function of stoichiometry have been made in the YBa{sub 2}Cu{sub 3}O{sub x}, and NdBa{sub 2}Cu{sub 3}O{sub x}, and Nd{sub 1.81}Ce{sub 0.19}CuO{sub x} superconducting systems in the temperature range 400--750{degree}C by means of an oxygen titration technique with an yttria-stabilized zirconia electrolyte. The object of our current measurements is to investigate the effect of ionic size of Y, Gd and Nd on the thermodynamic behavior and structural transition in the LnBa{sub 2}Cu{sub 3}O{sub x} system. The shape of the 400{degree}C isotherm for NdBa{sub 2}Cu{sub 3}O{sub x} suggests the presence of a miscibility gap at lower temperatures, at values of x that are higher than those in the YBa{sub 2}Cu{sub 3}O{sub x} system. The locations of the miscibility gaps are consistent with the effects of ionic radii on the composition dependence of {Tc} for these systems. Our results explain the two plateaus in measured value of {Tc} as a function of composition for the YBa{sub 2}Cu{sub 3}O{sub x} system and appear to be consistent with the less pronounced {Tc} plateaus found for the NdBa{sub 2}Cu{sub 3}O{sub x} system higher stoichiometry values. For a given oxygen stoichiometry, partial pressures of oxygen above NdBa{sub 2}Cu{sub 3}O{sub x} are higher than for the YBa{sub 2}Cu{sub 3}O{sub x} system in accord with calculated partial molar thermodynamic quantities. The results of limited measurements on the n-type (electron-doped) superconducting Nd{sub 1.81}Ce{sub 0.19}CuO{sub x} system will be presented. A thermodynamic assessment and intercomparison of our oxygen partial pressure measurements with the results of other measurements will be presented. 34 refs., 9 figs., 1 tab.

Tetenbaum, M.; Tumidajaski, P.; Bloom, I.D.; Brown, D.L.; Blander, M.

1991-01-01

121

Absolute configuration of isovouacapenol C  

PubMed Central

The title compound, C27H34O5 {systematic name: (4aR,5R,6R,6aS,7R,11aS,11bR)-4a,6-dihy­droxy-4,4,7,11b-tetra­methyl-1,2,3,4,4a,5,6,6a,7,11,11a,11b-dodeca­hydro­phenanthro[3,2-b]furan-5-yl benzoate}, is a cassane furan­oditerpene, which was isolated from the roots of Caesalpinia pulcherrima. The three cyclo­hexane rings are trans fused: two of these are in chair conformations with the third in a twisted half-chair conformation, whereas the furan ring is almost planar (r.m.s. deviation = 0.003?Å). An intra­molecular C—H?O inter­action generates an S(6) ring. The absolute configurations of the stereogenic centres at positions 4a, 5, 6, 6a, 7, 11a and 11b are R, R, R, S, R, S and R, respectively. In the crystal, mol­ecules are linked into infinite chains along [010] by O—H?O hydrogen bonds. C?O [3.306?(2)–3.347?(2)?Å] short contacts and C—H?? inter­actions also occur. PMID:21588364

Fun, Hoong-Kun; Yodsaoue, Orapun; Karalai, Chatchanok; Chantrapromma, Suchada

2010-01-01

122

Absolute Income, Relative Income, and Happiness  

ERIC Educational Resources Information Center

This paper uses data from the World Values Survey to investigate how an individual's self-reported happiness is related to (i) the level of her income in absolute terms, and (ii) the level of her income relative to other people in her country. The main findings are that (i) both absolute and relative income are positively and significantly…

Ball, Richard; Chernova, Kateryna

2008-01-01

123

Absolute Optical Metrology: Nanometers to Kilometers  

Microsoft Academic Search

We provide an overview of developments in high-accuracy absolute optical metrology with emphasis on space-based applications. Specific work on the Modulation Sideband Technology for Absolute Ranging (MSTAR) sensor is described along with novel applications of the sensor.

S. Dubovitsky; O. P. Lay; R. D. Peters; C. C. Liebe

2005-01-01

124

Nonequilibrium equalities in absolutely irreversible processes  

NASA Astrophysics Data System (ADS)

We generalize nonequilibrium integral equalities to situations involving absolutely irreversible processes for which the forward-path probability vanishes and the entropy production diverges, rendering conventional integral fluctuation theorems inapplicable. We identify the mathematical origins of absolute irreversibility as the singularity of probability measure. We demonstrate the validity of the obtained equalities for several models.

Murashita, Yûto; Funo, Ken; Ueda, Masahito

2014-10-01

125

Absolute instability of the Gaussian wake profile  

NASA Technical Reports Server (NTRS)

Linear parallel-flow stability theory has been used to investigate the effect of viscosity on the local absolute instability of a family of wake profiles with a Gaussian velocity distribution. The type of local instability, i.e., convective or absolute, is determined by the location of a branch-point singularity with zero group velocity of the complex dispersion relation for the instability waves. The effects of viscosity were found to be weak for values of the wake Reynolds number, based on the center-line velocity defect and the wake half-width, larger than about 400. Absolute instability occurs only for sufficiently large values of the center-line wake defect. The critical value of this parameter increases with decreasing wake Reynolds number, thereby indicating a shrinking region of absolute instability with decreasing wake Reynolds number. If backflow is not allowed, absolute instability does not occur for wake Reynolds numbers smaller than about 38.

Hultgren, Lennart S.; Aggarwal, Arun K.

1987-01-01

126

An electromagnetic thermotherapy system with a deep penetration depth for percutaneous thermal ablation.  

PubMed

Thermal ablation has been a promising method to remove the cancerous tissues. Electromagnetic-based thermotherapy has been extensively investigated for a variety of medical applications recently. In this study, a prototype electromagnetic thermotherapy system has been developed with a new coil design and a two-section needle. The coil can generate an alternating electromagnetic field (EMF) with a deep penetration depth to remotely heat the needle which is located up to 15 cm away, enabling percutaneous thermal ablation. Several important parameters, including the heating effects of the needle at different positions, the intensity of the EMF and the induced temperature distribution on the surrounding tissue, are first explored. An in vitro animal experiment has also been performed which shows EMF-induced ablation in a porcine liver by the needle. Furthermore, an in vivo experiment on an animal model (a New Zealand white rabbit) is also conducted in the study. Thus, the two-section needle combined with the coil-generated EMF has been demonstrated to be a promising thermotherapy system for percutaneous thermal ablation. PMID:23990331

Huang, Sheng-Chieh; Chang, Yi-Yuan; Kang, Jui-Wen; Tsai, Hung-Wen; Shan, Yan-Shen; Lin, Xi-Zhang; Lee, Gwo-Bin

2014-01-01

127

Nepal and the Americas: Can Electromagnetic Field (EMF) Signals Be Detected There That Yield Information About Culturally Dictated Spiritual Values, and Can Computers Interface Their Assessment?  

NASA Astrophysics Data System (ADS)

Nepal has a particularly rich tradition of culturally developed views on the material and spiritual worlds, and also has a powerful natural environment that may generate EMFs in conjunction with natural phenomena. We have an interest in determining whether these can be detected by portable technological means, and recording such data on notebook-type computers for analysis and evaluation. One goal is to assess whether historic Native Americans, such as Maine's and New Hampshire's Molly Ockett, may have been motivated in their selection of special, and perhaps, to them, "sacred" sites for their attention and as possible burial sites. Some of these may have been chosen on the basis of the EMFs that seem to emanate from them, and their assessment of what they meant to their worldviews. Do some Amerindians consider the EMF and reincarnation as requiring their rejection of material aspects of existence? Could other traditional cultures, or even suicidal terrorists, be sensitive to "information" they may receive from the EMF?

Aryal, Sanjita; Mc Leod, Roger D.; Mc Leod, David M.

2002-10-01

128

Impedance of a Spacecraft-Borne Antenna in the Magnetospheric Plasma and Quasi-Equilibrium Noise EMF in the Lower-Hybrid Frequency Band  

NASA Astrophysics Data System (ADS)

We present analytical and numerical estimations of the value and frequency dependence of the impedance and noise electromotive force (EMF) in the context of the conditions which correspond to the trajectories and parameters of the antennas borne by geophysical monitoring satellites. The estimations were obtained for two circular orbits at altitudes of 600 and 1200 km over the Earth's surface in the frequency range from 20 to 120 kHz, which corresponded to the area of the lower-hybrid resonance, where a higher level of noise emissions is observed at the altitudes under consideration. It is shown that near the lower-hybrid resonance frequency, the real part of the antenna impedance is determined by the resonant "monopole" loss by radiation of quasipotential waves. In the nonresonant frequency band (at the frequencies below the frequency of the lowerhybrid resonance), the antenna reactance is determined by the transit loss, which is, however, low as compared with the resonant loss. When the noise was calculated, the medium was assumed to be a two-temperature plasma. The spectral density of the power of the noise EMF lies in the range and is determined mainly by suprathermal electrons. In the nonresonant frequency band, the efficient temperature of noise radiation is equal to the temperature of the "cold" plasma component, and the antenna reactance is determined by the transit loss, i.e., the level of the noise EMF is low as compared with the EMF in the resonant frequency band.

Chugunov, Yu. V.; Grach, V. S.; Pasmanik, D. L.

2013-07-01

129

Are Naturopathic Universities ``The Natural Places'' to investigate Attention-Deficit Type Disorders, with Possible Linkages to Cultural Patterns and the EMF?  

Microsoft Academic Search

We desire serious investigations of behavioral impacts of certain localized or larger-scale environmental elements, such as the electromagnetic spectrum as detected by us at some sites. One author was impacted by the earth's EMF to such an extent in FL that it falsely convinced him that he was having a heart attack more severe than his nearly fatal one. Instead,

Beatriz de Souza; Chan Balam Matagamon; Sagamo Pawa Matagamon

2006-01-01

130

Floridas Miami Tequesta Indian Site, Its Calusa Indian Locations, the Matacumbe Keys, and Orlandos Wikiwa Springs Generate Environmentally Significant EMFs.  

NASA Astrophysics Data System (ADS)

Florida purchased the Tequesta ([Langue] doc Christ Spirit-signal) Indian site along the Miami River site that vigorously pulsates with even minor rainstorms entering or leaving the area. Although there is a laughable chimera of a fountain of youth associated with Ponce de Leons discovery of the Florida peninsula in about AD 1513, the Calusa (Royal Christ Jesus Spirit-signal) Indian Nation has an associated significance with EMF signals they possibly monitored throughout their area of activity. Our efforts have also led to the investigation of cultural and other influences implied by the Matacumbe Keys that indicate a shared commonality of awareness with Native Americans of the northeast such as Metacomet, or regions like Maines Grand Lake Matagamon and its associated electromagnetic Spirit Signal. Wikiwa Springs near Orlando shares much with Massachusetts (adherent of serpent Jesus Christ Spirit-signal) Natick, and New Hampshires Naticook Island. These are the locales of environmentally sensitive instrumentation.

Mac Dougall, Jean S.; Mc Leod, Roger D.; Mc Leod, David M.

2003-10-01

131

Magnifying absolute instruments for optically homogeneous regions  

NASA Astrophysics Data System (ADS)

We propose a class of magnifying absolute optical instruments with a positive isotropic refractive index. They create magnified stigmatic images, either virtual or real, of optically homogeneous three-dimensional spatial regions within geometrical optics.

Tyc, Tomáš

2011-09-01

132

Absolute vs. intensity-based emission caps  

E-print Network

Cap-and-trade systems limit emissions to some pre-specified absolute quantity. Intensity-based limits, that restrict emissions to some pre-specified rate relative to input or output, are much more widely used in environmental ...

Ellerman, A. Denny.

133

The Simplicity Argument and Absolute Morality  

ERIC Educational Resources Information Center

In this paper the author has maintained that there is a similarity of thought to be found in the writings of Cudworth, Emerson, and Husserl in his investigation of an absolute system of morality. (Author/RK)

Mijuskovic, Ben

1975-01-01

134

A Cryogenic Radiometer for Absolute Radiometric Measurements  

Microsoft Academic Search

The adoption in 1979 of a new definition of the candela, which permitted a detector-based approach to the realization of the unit, has emphasized the importance of high-accuracy absolute radiation detectors. This paper describes a new electrical-substitution absolute radiometer operating at 5 K, based on a standard commercial helium cryostat, which has been developed at NPL for optical radiant-power measurements.

J E Martin; N P Fox; P J Key

1985-01-01

135

MSTAR: a submicrometer absolute metrology system.  

PubMed

The Modulation Sideband Technology for Absolute Ranging (MSTAR) sensor permits absolute distance measurement with subnanometer accuracy, an improvement of 4 orders of magnitude over current techniques. The system uses fast phase modulators to resolve the integer cycle ambiguity of standard interferometers. The concept is described and demonstrated over target distances up to 1 m. The design can be extended to kilometer-scale separations. PMID:12816236

Lay, O P; Dubovitsky, S; Peters, R D; Burger, J P; Ahn, S W; Steier, W H; Fetterman, H R; Chang, Y

2003-06-01

136

Absolute Temperature Monitoring Using RF Radiometry in the MRI Scanner  

PubMed Central

Temperature detection using microwave radiometry has proven value for noninvasively measuring the absolute temperature of tissues inside the body. However, current clinical radiometers operate in the gigahertz range, which limits their depth of penetration. We have designed and built a noninvasive radiometer which operates at radio frequencies (64 MHz) with ?100-kHz bandwidth, using an external RF loop coil as a thermal detector. The core of the radiometer is an accurate impedance measurement and automatic matching circuit of 0.05 ? accuracy to compensate for any load variations. The radiometer permits temperature measurements with accuracy of ±0.1°K, over a tested physiological range of 28° C–40° C in saline phantoms whose electric properties match those of tissue. Because 1.5 T magnetic resonance imaging (MRI) scanners also operate at 64 MHz, we demonstrate the feasibility of integrating our radiometer with an MRI scanner to monitor RF power deposition and temperature dosimetry, obtaining coarse, spatially resolved, absolute thermal maps in the physiological range. We conclude that RF radiometry offers promise as a direct, noninvasive method of monitoring tissue heating during MRI studies and thereby providing an independent means of verifying patient-safe operation. Other potential applications include titration of hyper- and hypo-therapies. PMID:18026562

El-Sharkawy, AbdEl-Monem M.; Sotiriadis, Paul P.; Bottomley, Paul A.; Atalar, Ergin

2007-01-01

137

Jasminum flexile flower absolute from India--a detailed comparison with three other jasmine absolutes.  

PubMed

Jasminum flexile flower absolute from the south of India and the corresponding vacuum headspace (VHS) sample of the absolute were analyzed using GC and GC-MS. Three other commercially available Indian jasmine absolutes from the species: J. sambac, J. officinale subsp. grandiflorum, and J. auriculatum and the respective VHS samples were used for comparison purposes. One hundred and twenty-one compounds were characterized in J. flexile flower absolute, with methyl linolate, benzyl salicylate, benzyl benzoate, (2E,6E)-farnesol, and benzyl acetate as the main constituents. A detailed olfactory evaluation was also performed. PMID:19831037

Braun, Norbert A; Kohlenberg, Birgit; Sim, Sherina; Meier, Manfred; Hammerschmidt, Franz-Josef

2009-09-01

138

Signalling problem in absolutely unstable systems  

NASA Astrophysics Data System (ADS)

The dynamics of unstable systems crucially depends on the nature of the instability, either convective or absolute. The signalling problem, which is the study of the spatial response to a localized time-harmonic forcing, is generally believed to be relevant only for stable or convectively unstable systems and to be ill-posed for absolutely unstable systems, where the self-sustained perturbations grow faster than the forced harmonic response. The present investigation shows that the signalling problem may still be well posed for media displaying absolutely unstable regions. Considering weakly spatially inhomogenous systems, conditions are derived for the validity of the signalling problem. The complete spatial response to harmonic forcing is first analytically derived in terms of asymptotic approximations and then confirmed by direct numerical simulations.

Pier, Benoît

2011-06-01

139

Absolute Zero: Community Education Outreach Guide  

NSDL National Science Digital Library

This guide provides curricular resources for study of the history and science of the quest for ever colder temperature. Designed for teachers and informal educators of middle school students. this guide offers hands-on demonstrations, questions to encourage student participation, suggestions for class activities, and ways to encourage students to continue studying the science. Topics include low-temperature physics and the impact of technologies such as air conditioning, refrigeration and liquefied gases. This material is related to a two-part public broadcasting special, Absolute Zero, produced by Meridian Productions and Windfall Films. Absolute Zero is underwritten by the National Science Foundation and the Alfred P. Sloan Foundation and is based largely on Tom Shachtmanâs acclaimed book, Absolute Zero and the Conquest of Cold.

2008-09-18

140

Absolute Photoacoustic Thermometry in Deep Tissue  

PubMed Central

Photoacoustic (PA) thermography is a promising tool for temperature measurement in deep tissue. Here, we propose an absolute temperature measurement method based on the dual temperature dependences of the Grüneisen parameter and the speed of sound in tissue. By taking ratiometric measurements at two adjacent temperatures, we can eliminate the factors that are temperature irrelevant but difficult to correct for in deep tissue. To validate our method, absolute temperatures of blood-filled tubes embedded ~9 mm deep in chicken tissue were measured in a biologically relevant range from 28 °C to 46 °C. The temperature measurement accuracy was ~0.6 °C. The results suggest that our method can be potentially used for absolute temperature monitoring in deep tissue during thermotherapy. PMID:24322224

Tai, Stephen; Zhou, Yong; Wang, Lihong V.

2013-01-01

141

Absolute photoacoustic thermometry in deep tissue.  

PubMed

Photoacoustic thermography is a promising tool for temperature measurement in deep tissue. Here we propose an absolute temperature measurement method based on the dual temperature dependences of the Grüneisen parameter and the speed of sound in tissue. By taking ratiometric measurements at two adjacent temperatures, we can eliminate the factors that are temperature irrelevant but difficult to correct for in deep tissue. To validate our method, absolute temperatures of blood-filled tubes embedded ~9 mm deep in chicken tissue were measured in a biologically relevant range from 28°C to 46°C. The temperature measurement accuracy was ~0.6°C. The results suggest that our method can be potentially used for absolute temperature monitoring in deep tissue during thermotherapy. PMID:24322224

Yao, Junjie; Ke, Haixin; Tai, Stephen; Zhou, Yong; Wang, Lihong V

2013-12-15

142

Absolute distance metrology for space interferometers  

NASA Astrophysics Data System (ADS)

Space interferometers consisting of several free flying telescopes, such as the planned Darwin mission, require a complex metrology system to make all the components operate as a single instrument. Our research focuses on one of its sub-systems that measures the absolute distance between two satellites with high accuracy. For Darwin the required accuracy would be in the order of 10 µm over 250 meter. To measure this absolute distance, we are currently exploring the frequency sweeping interferometry technique. Its measurement principle is to first measure a phase in the interferometer, sweep a tunable laser over a known frequency interval and finally measure a second phase. By also counting the number of fringes during the sweep it is possible to determine the absolute path length difference without ambiguities. The wavelength at the endpoints of the sweep is stabilized on a Fabry-Perot cavity. In this way the unknown distance is directly referenced to the length of the Fabry-Perot cavity.

Swinkels, Bas L.; Wendrich, Thijs J.; Bhattacharya, Nandini; Wielders, Arno A.; Braat, Joseph J.

2004-09-01

143

Precise Measurement of the Absolute Fluorescence Yield  

SciTech Connect

We present preliminary results of the absolute yield of fluorescence emission in atmospheric gases. Measurements were performed at the Fermilab Test Beam Facility with a variety of beam particles and gases. Absolute calibration of the fluorescence yield to 5% level was achieved by comparison with two known light sources - the Cherenkov light emitted by the beam particles, and a calibrated nitrogen laser. The uncertainty of the energy scale of current Ultra-High Energy Cosmic Rays experiments will be significantly improved by the AIRFLY measurement.

Ave, M.; Daumiller, K.; Keilhauer, B.; Klages, H.; Salamida, F.; Smida, R. [Karlsruhe Institute of Technology, IK, Postfach 6980, D - 76021 Karlsruhe (Germany); Bohacova, M.; Nozka, L.; Palatka, M.; Ridky, J.; Schovanek, P. [Institute of Physics of the Academy of Sciences of the Czech Republic, Na Slovance 2, CZ-182 21 Praha 8 (Czech Republic); Di Carlo, P.; Iarlori, M.; Petrera, S.; Rizi, V. [Dipartimento di Fisica dell'Universita de l'Aquila and INFN, Via Vetoio, I-67010 Coppito, Aquila (Italy); Di Giulio, C.; Verzi, V. [Dipartimento di Fisica dell'Universita di Roma Tor Vergata and Sezione INFN, Via della Ricerca Scientifica, I-00133 Roma (Italy); San Luis, P. Facal; Monasor, M.; Privitera, P. [University of Chicago, Enrico Fermi Institute and Kavli Institute for Cosmological Physics, 5640 S. Ellis Ave., Chicago, IL 60637 (United States)

2011-09-22

144

Absolute measurement of hyperspectral and angular reflection.  

PubMed

A new instrument for absolute measurement of hyperspectral and angular reflection is presented. The instrument determines absolute values of angular reflection quantities in a wavelength range from 380 to 780 nm with a 3 nm spectral resolution by using a white source and a CCD-based spectroradiometer. Through uncertainty evaluation, the measurement uncertainty is determined as 1.4%-2.9% (k=2) for white diffuse material of Spectralon. The gonioreflectometric determination and an integrating-sphere-based reflection measurement traceable to KRISS spectral reflectance scale are compared by determining hemispherical reflectance, which results in agreement in their uncertainties. PMID:25322100

Hwang, Jisoo

2014-09-20

145

An Improved Model for the Back-EMF and Cogging Torque Characteristics of a Novel Axial Flux Permanent Magnet Synchronous Machine With a Segmental Laminated Stator  

Microsoft Academic Search

An improved model for the back-electromagnetic-force (back-EMF) and cogging torque characteristics of a novel axial flux permanent magnet (AFPM) synchronous machine with a segmental laminated stator is presented. Based on a 3-D finite-element analysis (FEA) modeling approach that takes into the anisotropic properties of the machine's laminated cores, the proposed model provides superior performance prediction to existing isotropic models, in

W. Fei; P. C. K. Luk

2009-01-01

146

PROJECTIVE GROUP STRUCTURES AS ABSOLUTE GALOIS STRUCTURES  

E-print Network

PROJECTIVE GROUP STRUCTURES AS ABSOLUTE GALOIS STRUCTURES WITH BLOCK APPROXIMATION # by Dan Haran Bonn, Germany e­mail: pop@math.uni­bonn.de Abstract. A proper profinite group structure G is projective of a cover to a cartesian square . . . . . . . . . . . . . . . 19 4. Projective group structures

Pop, Florian

147

Absolute Points for Multiple Assignment Problems  

ERIC Educational Resources Information Center

An algorithm is presented to solve multiple assignment problems in which a cost is incurred only when an assignment is made at a given cell. The proposed method recursively searches for single/group absolute points to identify cells that must be loaded in any optimal solution. Unlike other methods, the first solution is the optimal solution. The…

Adlakha, V.; Kowalski, K.

2006-01-01

148

HARDCOVER JACKET COPY--FLAPS Absolutely Small  

E-print Network

salt dissolve in water, while oil does not, and much more "There are a few books that I always keep Michael D. Fayer, Ph.D. Our intuition about how things should behave is usually right in the everyday, Absolutely Small develops your intuition for the nature of things at their smallest and most intriguing level

Fayer, Michael D.

149

High-accuracy absolute distance metrology Proefschrift  

E-print Network

High-accuracy absolute distance metrology Proefschrift ter verkrijging van de graad van doctor aan-ray telescopes and synthetic aperture telescopes. For most of these, a metrology system that measures with a complex metrology system that monitors all the distances, angles and velocities in the system

150

Absolute Irreducibility of Polynomials via Newton Polytopes  

Microsoft Academic Search

A multivariable polynomial is associated with a polytope, called its Newton polytope. A polynomial is absolutely irreducible if its Newton polytope is indecomposable in the sense of Minkowski sum of polytopes. Two general constructions of indecomposable polytopes are given, and they give many simple irreducibility criteria including the well-known Eisenstein criterion. Polynomials from these criteria are over any field and

Shuhong Gao

2001-01-01

151

Absolute measurement of activity of ¹??Au foils using the 4??-? coincidence counting method and corrections by the Monte Carlo simulation.  

PubMed

The thermal neutron fluence rate is determined by the gold activation method. The absolute activity of the irradiated gold foil is measured by a 4??-? coincidence counter. Using this method, corrections for the detection of conversion electrons and gamma rays by a 4?? counter are very important to obtain accurate absolute activity. In this work, Monte Carlo simulations were performed to derive the correction factor K. The absolute measurement of (198)Au activity for 20-100 ?m thickness Au foils were performed to verify the calculating model of the 4??-? coincidence counting system. PMID:21406431

Nishiyama, Jun; Harano, Hideki; Matsumoto, Tetsuro; Sato, Yasushi; Uritani, Akira; Kudo, Katsuhisa

2012-01-01

152

Absolute calibration of TFTR helium proportional countersa)  

NASA Astrophysics Data System (ADS)

The TFTR helium proportional counters are located in the central five (5) channels of the TFTR multichannel neutron collimator. These detectors were absolutely calibrated using a 14 MeV neutron generator positioned at the horizontal midplane of the TFTR vacuum vessel. The neutron generator position was scanned in centimeter steps to determine the collimator aperture width to 14 MeV neutrons and the absolute sensitivity of each channel. Neutron profiles were measured for TFTR plasmas with time resolution between 5 and 50 ms depending upon count rates. The He detectors were used to measure the burnup of 1 MeV tritons in deuterium plasmas, the transport of tritium in trace tritium experiments, and the residual tritium levels in plasmas following 50:50 DT experiments.

Strachan, J. D.; Barnes, Cris W.; Diesso, M.; Jassby, D.; Johnson, L.; Loughlin, M.; McCauley, S.; Munsat, T.; Roquemore, A. L.

1995-02-01

153

Absolute-magnitude Distributions of Supernovae  

NASA Astrophysics Data System (ADS)

The absolute-magnitude distributions of seven supernova (SN) types are presented. The data used here were primarily taken from the Asiago Supernova Catalogue, but were supplemented with additional data. We accounted for both foreground and host-galaxy extinction. A bootstrap method is used to correct the samples for Malmquist bias. Separately, we generate volume-limited samples, restricted to events within 100 Mpc. We find that the superluminous events (MB < -21) make up only about 0.1% of all SNe in the bias-corrected sample. The subluminous events (MB > -15) make up about 3%. The normal Ia distribution was the brightest with a mean absolute blue magnitude of -19.25. The IIP distribution was the dimmest at -16.75.

Richardson, Dean; Jenkins, Robert L., III; Wright, John; Maddox, Larry

2014-05-01

154

An absolute measure for a key currency  

NASA Astrophysics Data System (ADS)

It is generally considered that the US dollar and the euro are the key currencies in the world and in Europe, respectively. However, there is no absolute general measure for a key currency. Here, we investigate the 24-hour periodicity of foreign exchange markets using a recurrence plot, and define an absolute measure for a key currency based on the strength of the periodicity. Moreover, we analyze the time evolution of this measure. The results show that the credibility of the US dollar has not decreased significantly since the Lehman shock, when the Lehman Brothers bankrupted and influenced the economic markets, and has increased even relatively better than that of the euro and that of the Japanese yen.

Oya, Shunsuke; Aihara, Kazuyuki; Hirata, Yoshito

155

A Global Approach to Absolute Parallelism Geometry  

NASA Astrophysics Data System (ADS)

In this paper we provide a global investigation of the geometry of parallelizable manifolds (or absolute parallelism geometry) frequently used in applications. We discuss different linear connections and curvature tensors from a global point of view. We give an existence and uniqueness theorem for a remarkable linear connection, called the canonical connection. Different curvature tensors are expressed in a compact form in terms of the torsion tensor of the canonical connection only. Using the Bianchi identities, some interesting identities are derived. An important special fourth-order tensor, which we refer to as Wanas tensor, is globally defined and investigated. Finally a "double-view" for the fundamental geometric objects of an absolute parallelism space is established: The expressions of these geometric objects are computed in the parallelization basis and are compared with the corresponding local expressions in the natural basis. Physical aspects of some geometric objects considered are pointed out.

Youssef, Nabil L.; Elsayed, Waleed A.

2013-08-01

156

Absolute and relative dosimetry for ELIMED  

SciTech Connect

The definition of detectors, methods and procedures for the absolute and relative dosimetry of laser-driven proton beams is a crucial step toward the clinical use of this new kind of beams. Hence, one of the ELIMED task, will be the definition of procedures aiming to obtain an absolute dose measure at the end of the transport beamline with an accuracy as close as possible to the one required for clinical applications (i.e. of the order of 5% or less). Relative dosimetry procedures must be established, as well: they are necessary in order to determine and verify the beam dose distributions and to monitor the beam fluence and the energetic spectra during irradiations. Radiochromic films, CR39, Faraday Cup, Secondary Emission Monitor (SEM) and transmission ionization chamber will be considered, designed and studied in order to perform a fully dosimetric characterization of the ELIMED proton beam.

Cirrone, G. A. P.; Schillaci, F.; Scuderi, V. [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and Institute of Physics Czech Academy of Science, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic)] [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and Institute of Physics Czech Academy of Science, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic); Cuttone, G.; Candiano, G.; Musumarra, A.; Pisciotta, P.; Romano, F. [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy)] [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Carpinelli, M. [INFN Sezione di Cagliari, c/o Dipartimento di Fisica, Università di Cagliari, Cagliari (Italy)] [INFN Sezione di Cagliari, c/o Dipartimento di Fisica, Università di Cagliari, Cagliari (Italy); Leonora, E.; Randazzo, N. [INFN-Sezione di Catania, Via Santa Sofia 64, Catania (Italy)] [INFN-Sezione di Catania, Via Santa Sofia 64, Catania (Italy); Presti, D. Lo [INFN-Sezione di Catania, Via Santa Sofia 64, Catania, Italy and Università di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, Catania (Italy)] [INFN-Sezione di Catania, Via Santa Sofia 64, Catania, Italy and Università di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, Catania (Italy); Raffaele, L. [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and INFN-Sezione di Catania, Via Santa Sofia 64, Catania (Italy)] [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and INFN-Sezione di Catania, Via Santa Sofia 64, Catania (Italy); Tramontana, A. [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and Università di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, Catania (Italy)] [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and Università di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, Catania (Italy); Cirio, R.; Sacchi, R.; Monaco, V. [INFN, Sezione di Torino, Via P.Giuria, 1 10125 Torino, Italy and Università di Torino, Dipartimento di Fisica, Via P.Giuria, 1 10125 Torino (Italy)] [INFN, Sezione di Torino, Via P.Giuria, 1 10125 Torino, Italy and Università di Torino, Dipartimento di Fisica, Via P.Giuria, 1 10125 Torino (Italy); Marchetto, F.; Giordanengo, S. [INFN, Sezione di Torino, Via P.Giuria, 1 10125 Torino (Italy)] [INFN, Sezione di Torino, Via P.Giuria, 1 10125 Torino (Italy)

2013-07-26

157

Absolute distance metrology for space interferometers  

NASA Astrophysics Data System (ADS)

Future space missions, among which the Darwin Space Interferometer, will consist of several free flying satellites. A complex metrology system is required to have all the components fly accurately in formation and have it operate as a single instrument. Our work focuses on a possible implementation of the sub-system that measures the absolute distance between two satellites with high accuracy. For Darwin the required accuracy is on the order of 70 micrometer over a distance of 250 meter. We are exploring a technique called frequency sweeping interferometry, which involves interferometrically measuring a phase difference while sweeping the wavelength of a tunable laser. This phase difference is directly proportional to the absolute distance. A very high finesse Fabry-Perot cavity is used as a reference standard, to which the laser is locked at the end-points of the sweep. We will discuss our measurement scheme, our set-up and some first measurements.

Swinkels, Bas L.; Latoui, Abdelhalim; Bhattacharya, Nandini; Wielders, Arno A.; Braat, Joseph J. M.

2005-08-01

158

Absolute distance metrology for space interferometers  

NASA Astrophysics Data System (ADS)

Future space missions, among which the Darwin Space Interferometer, will consist of several free flying satellites. A complex metrology system is required to have all the components fly accurately in formation and have it operate as a single instrument. Our work focuses on a possible implementation of the sub-system that measures the absolute distance between two satellites with high accuracy. For Darwin the required accuracy is on the order of 70 micrometer over a distance of 250 meter. We are exploring a technique called frequency sweeping interferometry, which involves interferometrically measuring a phase difference while sweeping the wavelength of a tunable laser. This phase difference is directly proportional to the absolute distance. A very high finesse Fabry-Perot cavity is used as a reference standard, to which the laser is locked end-points of the sweep. We will discuss the control system that drives the setup and show some first experimental results.

Swinkels, Bas L.; Bhattacharya, Nandini; Wielders, Arno A.; Braat, Joseph J. M.

2005-06-01

159

Absolute photoionization cross sections of atomic oxygen  

NASA Technical Reports Server (NTRS)

The absolute values of photoionization cross sections of atomic oxygen were measured from the ionization threshold to 120 A. An auto-ionizing resonance belonging to the 2S2P4(4P)3P(3Do, 3So) transition was observed at 479.43 A and another line at 389.97 A. The experimental data is in excellent agreement with rigorous close-coupling calculations that include electron correlations in both the initial and final states.

Samson, J. A. R.; Pareek, P. N.

1985-01-01

160

Absolute photoionization cross sections of atomic oxygen  

NASA Technical Reports Server (NTRS)

The absolute values of photoionization cross sections of atomic oxygen were measured from the ionization threshold to 120 A. An auto-ionizing resonance belonging to the 2S2P4(4P)3P(3Do, 3So) transition was observed at 479.43 A and another line at 389.97 A. The experimental data is in excellent agreement with rigorous close-coupling calculations that include electron correlations in both the initial and final states.

Samson, J. A. R.; Pareek, P. N.

1982-01-01

161

On absolute CM-periods, II  

Microsoft Academic Search

For a CM-fieldK, Shimura defined the period symbolpK by factorizing periods of abelian varieties with complex multiplication. We define the absolute period symbolgK using division values of the multiple gamma function and conjecture that pK coincides with gK up to the multiplication by algebraic numbers. Taking the action of Gal(Q Q) into account, we present a refined version of this

Hiroyuki Yoshida

1998-01-01

162

The absolute bioavailability of caffeine in man  

Microsoft Academic Search

The absolute bioavailability of orally administered caffeine was investigated in 10 healthy adult male volunteers, aged 18.8 to 30.0 years. The subjects were administered a 5 mg\\/kg dose of caffeine as either an aqueous oral solution or an intravenous infusion, on separate occasions about 1 week apart, in a randomized crossover fashion. Plasma samples were collected over the 24-h period

J. Blanchard; S. J. A. Sawers

1983-01-01

163

The absolute spectrophotometric catalog by Anita Cochran  

NASA Astrophysics Data System (ADS)

The absolute spectrophotometric catalog by Anita Cochran is presented in a machine-readable form. The catalog systematizes observations acquired at the McDonald Observatory in 1977-1978. The data are compared with other sources, in particular, the calculated broadband stellar magnitudes are compared with photometric observations by other authors, to show that the observational data given in the catalog are reliable and suitable for a variety of applications. Observations of variable stars of different types make Cochran's catalog especially valuable.

Burnashev, V. I.; Burnasheva, B. A.; Ruban, E. V.; Hagen-Torn, E. I.

2014-06-01

164

The absolute position of a resonance peak  

E-print Network

It is common practice in scattering theory to correlate between the position of a resonance peak in the cross section and the real part of a complex energy of a pole of the scattering amplitude. In this work we show that the resonance peak position appears at the absolute value of the pole's complex energy rather than its real part. We further demonstrate that a local theory of resonances can still be used even in cases previously thought impossible.

Shachar Klaiman; Nimrod Moiseyev

2010-05-26

165

Absolute distance metrology for space interferometers  

NASA Astrophysics Data System (ADS)

Space interferometers consisting of several free flying telescopes, such as the planned Darwin mission, require a complex metrology system to make all the components operate as a single instrument. This metrology system consists of various sub-systems to monitor distances, angles and speeds. Our research focuses on one of these sub-systems that measures the absolute distance between two satellites with high accuracy. For Darwin the required accuracy would be in the order of 10 ?m over 250 meter. To measure this absolute distance, we are currently building a frequency sweeping interferometer. It is operated by first measuring a phase in the interferometer, sweeping a tunable laser over a known frequency interval and finally measuring a second phase. By also counting the number of fringes during the sweep it is possible to determine the absolute path length difference without ambiguities. We plan on actively stabilizing the wavelength at the endpoints of the sweep on a Fabry-Perot cavity using the Pound-Drever-Hall technique. In this way the unknown distance is directly referenced to the length of the Fabry-Perot cavity.

Swinkels, B. L.; Wendrich, T. J.; Bhattacharya, N.; Wielders, A. A.; Braat, J. J. M.

2004-06-01

166

Ge/Si(001) heterostructures with dense arrays of Ge quantum dots: morphology, defects, photo-emf spectra and terahertz conductivity  

PubMed Central

Issues of Ge hut cluster array formation and growth at low temperatures on the Ge/Si(001) wetting layer are discussed on the basis of explorations performed by high resolution STM and in-situ RHEED. Dynamics of the RHEED patterns in the process of Ge hut array formation is investigated at low and high temperatures of Ge deposition. Different dynamics of RHEED patterns during the deposition of Ge atoms in different growth modes is observed, which reflects the difference in adatom mobility and their ‘condensation’ fluxes from Ge 2D gas on the surface for different modes, which in turn control the nucleation rates and densities of Ge clusters. Data of HRTEM studies of multilayer Ge/Si heterostructures are presented with the focus on low-temperature formation of perfect films. Heteroepitaxial Si p–i–n-diodes with multilayer stacks of Ge/Si(001) quantum dot dense arrays built in intrinsic domains have been investigated and found to exhibit the photo-emf in a wide spectral range from 0.8 to 5 ?m. An effect of wide-band irradiation by infrared light on the photo-emf spectra has been observed. Photo-emf in different spectral ranges has been found to be differently affected by the wide-band irradiation. A significant increase in photo-emf is observed in the fundamental absorption range under the wide-band irradiation. The observed phenomena are explained in terms of positive and neutral charge states of the quantum dot layers and the Coulomb potential of the quantum dot ensemble. A new design of quantum dot infrared photodetectors is proposed. By using a coherent source spectrometer, first measurements of terahertz dynamical conductivity (absorptivity) spectra of Ge/Si(001) heterostructures were performed at frequencies ranged from 0.3 to 1.2 THz in the temperature interval from 300 to 5 K. The effective dynamical conductivity of the heterostructures with Ge quantum dots has been discovered to be significantly higher than that of the structure with the same amount of bulk germanium (not organized in an array of quantum dots). The excess conductivity is not observed in the structures with the Ge coverage less than 8 Å. When a Ge/Si(001) sample is cooled down the conductivity of the heterostructure decreases. PMID:22824144

2012-01-01

167

Study of Belousov—Zhabotinsky oscillators in water—acetonitrile medium employing EMF and EPR techniques with o-vanillin, p-vanillin and adrenaline as substrates  

NASA Astrophysics Data System (ADS)

The oscillatory behaviour of three substrates, ortho-vanillin, para-vanillin and adrenaline, in mixed media (water plus 20% acetonitrile) has been investigated using EPR and EMF techniques. All these substrates exhibit two types of oscillation involving Br 2/Br - and Mn(III)/Mn(II) redox couples. From the oscillatory characteristics (total time, number of oscillations and time per oscillation) obtained by employing these techniques, the reactivities of the vanillins have been correlated. The Field—Koros—Noyes mechanism, suggested for catalysed systems in pure aqueous medium, is established to be applicable even in mixed media.

Lalitha, P. V.; Ramaswamy, R.; Ramakrishnan, Geetha; Rao, P. Sambasiva

1994-12-01

168

Ge/Si(001) heterostructures with dense arrays of Ge quantum dots: morphology, defects, photo-emf spectra and terahertz conductivity.  

PubMed

: Issues of Ge hut cluster array formation and growth at low temperatures on the Ge/Si(001) wetting layer are discussed on the basis of explorations performed by high resolution STM and in-situ RHEED. Dynamics of the RHEED patterns in the process of Ge hut array formation is investigated at low and high temperatures of Ge deposition. Different dynamics of RHEED patterns during the deposition of Ge atoms in different growth modes is observed, which reflects the difference in adatom mobility and their 'condensation' fluxes from Ge 2D gas on the surface for different modes, which in turn control the nucleation rates and densities of Ge clusters. Data of HRTEM studies of multilayer Ge/Si heterostructures are presented with the focus on low-temperature formation of perfect films.Heteroepitaxial Si p-i-n-diodes with multilayer stacks of Ge/Si(001) quantum dot dense arrays built in intrinsic domains have been investigated and found to exhibit the photo-emf in a wide spectral range from 0.8 to 5 ?m. An effect of wide-band irradiation by infrared light on the photo-emf spectra has been observed. Photo-emf in different spectral ranges has been found to be differently affected by the wide-band irradiation. A significant increase in photo-emf is observed in the fundamental absorption range under the wide-band irradiation. The observed phenomena are explained in terms of positive and neutral charge states of the quantum dot layers and the Coulomb potential of the quantum dot ensemble. A new design of quantum dot infrared photodetectors is proposed.By using a coherent source spectrometer, first measurements of terahertz dynamical conductivity (absorptivity) spectra of Ge/Si(001) heterostructures were performed at frequencies ranged from 0.3 to 1.2 THz in the temperature interval from 300 to 5 K. The effective dynamical conductivity of the heterostructures with Ge quantum dots has been discovered to be significantly higher than that of the structure with the same amount of bulk germanium (not organized in an array of quantum dots). The excess conductivity is not observed in the structures with the Ge coverage less than 8 Å. When a Ge/Si(001) sample is cooled down the conductivity of the heterostructure decreases. PMID:22824144

Yuryev, Vladimir A; Arapkina, Larisa V; Storozhevykh, Mikhail S; Chapnin, Valery A; Chizh, Kirill V; Uvarov, Oleg V; Kalinushkin, Victor P; Zhukova, Elena S; Prokhorov, Anatoly S; Spektor, Igor E; Gorshunov, Boris P

2012-01-01

169

EMF wire code research  

SciTech Connect

This paper examines the results of previous wire code research to determines the relationship with childhood cancer, wire codes and electromagnetic fields. The paper suggests that, in the original Savitz study, biases toward producing a false positive association between high wire codes and childhood cancer were created by the selection procedure.

Jones, T.

1993-11-01

170

Determination of the absolute contours of optical flats  

NASA Technical Reports Server (NTRS)

Emersons procedure is used to determine true absolute contours of optical flats. Absolute contours of standard flats are determined and a comparison is then made between standard and unknown flats. Contour differences are determined by deviation of Fizeau fringe.

Primak, W.

1969-01-01

171

An absolute radius scale for Saturn's rings  

NASA Technical Reports Server (NTRS)

Radio and stellar occultation observations of Saturn's rings made by the Voyager spacecraft are discussed. The data reveal systematic discrepancies of almost 10 km in some parts of the rings, limiting some of the investigations. A revised solution for Saturn's rotation pole has been proposed which removes the discrepancies between the stellar and radio occultation profiles. Corrections to previously published radii vary from -2 to -10 km for the radio occultation, and +5 to -6 km for the stellar occultation. An examination of spiral density waves in the outer A Ring supports that the revised absolute radii are in error by no more than 2 km.

Nicholson, Philip D.; Cooke, Maren L.; Pelton, Emily

1990-01-01

172

Absolute Priority for a Vehicle in VANET  

NASA Astrophysics Data System (ADS)

In today's world, traffic jams waste hundreds of hours of our life. This causes many researchers try to resolve the problem with the idea of Intelligent Transportation System. For some applications like a travelling ambulance, it is important to reduce delay even for a second. In this paper, we propose a completely infrastructure-less approach for finding shortest path and controlling traffic light to provide absolute priority for an emergency vehicle. We use the idea of vehicular ad-hoc networking to reduce the imposed travelling time. Then, we simulate our proposed protocol and compare it with a centrally controlled traffic light system.

Shirani, Rostam; Hendessi, Faramarz; Montazeri, Mohammad Ali; Sheikh Zefreh, Mohammad

173

Note: Real-time absolute air refractometer.  

PubMed

We present a real-time absolute air refractometer benefiting from the synthetic pseudo-wavelength (SPW) method. Based on laser heterodyne interferometry, the SPW method uses three vacuum cells with specific lengths to synthesize a set of synthetic pseudo-wavelengths, by combination of which the refractive index can be determined directly without ambiguity. In addition, owing to the parallel arrangement of the vacuum cells in the optical path, the measured data can be collected simultaneously so that one measurement process can be less than 2 ms. The real-time feature makes it possible for instantaneous compensation for laser interferometers. PMID:24880432

Huang, Pei; Zhang, Jitao; Li, Yan; Wei, Haoyun

2014-05-01

174

Absolute method of measuring magnetic susceptibility  

USGS Publications Warehouse

An absolute method of standardization and measurement of the magnetic susceptibility of small samples is presented which can be applied to most techniques based on the Faraday method. The fact that the susceptibility is a function of the area under the curve of sample displacement versus distance of the magnet from the sample, offers a simple method of measuring the susceptibility without recourse to a standard sample. Typical results on a few substances are compared with reported values, and an error of less than 2% can be achieved. ?? 1959 The American Institute of Physics.

Thorpe, A.; Senftle, F.E.

1959-01-01

175

Continuum limit of electrostatic gyrokinetic absolute equilibrium  

SciTech Connect

Electrostatic gyrokinetic absolute equilibria with continuum velocity field are obtained through the partition function and through the Green function of the functional integral. The new results justify and explain the prescription for quantization/discretization or taking the continuum limit of velocity. The mistakes in the Appendix D of our earlier work [J.-Z. Zhu and G. W. Hammett, Phys. Plasmas 17, 122307 (2010)] are explained and corrected. If the lattice spacing for discretizing velocity is big enough, all the invariants could concentrate at the lowest Fourier modes in a negative-temperature state, which might indicate a possible variation of the dual cascade picture in 2D plasma turbulence.

Zhu Jianzhou [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

2012-06-15

176

Absolute temperature stability of passive imaging radiometers  

NASA Astrophysics Data System (ADS)

A challenge in the development of multi-channel millimeter wave imaging radiometers is overcoming effects associated with the temperature dependence of receiver responsivity. In this paper, the stability of absolute radiation temperature measurements, made with direct and heterodyne detection radiometers, is investigated theoretically and experimentally. The agreement between theory and experiment is found to be good. Changes in measured radiation temperatures were found to be between 6 degree(s)K at 35 GHz and 145 degree(s)K at 220 GHz, for a one degree change in instrumental temperature. Suggestions are made, as to how the temperature stability of radiometers may be improved.

Salmon, Neil A.; Borrill, Jonathan R.; Gleed, David G.

1997-06-01

177

On the invariant thermal Proca - Klein - Gordon equation  

E-print Network

In this paper we discuss the invariant thermal Proca - Klein - Gordon equation (PKG). We argue that for the thermal PKG equation the absolute velocity is equal v = alpha*c, where alpha is the fine stucture constant for electromagnetic interaction.

Magdalena Pelc

2007-10-14

178

[Effect of doxorubicine and heterogenous electromagnetic and thermal fields on the nonlinear dynamics of carcinoma Guerin development].  

PubMed

While local hyperthermia application the intratumoral blood flow is enhancing, leading to oxygenation and vascular permeability for antitumoral medicines. The work objective was to investigate the dependence of the development kinetics in carcinoma Gereni (CG) from combined action of doxorubicin (DR) and the kind of thermal impact, a contact one--due to a contact delivery of heat from a water heater and without contact - due to the tumor electromagnetic irradiation (EMI) using heterogenous electromagnetic field (EMF). DR was injected to the animals in a mass concentration of 1,5 mg on 1 kg of their body mass. The DR injection, a contact heating and EMI were started on the 8th day after the tumor reinoculation and kept on conducting once a 2 days. The course had included 5 injections and/or 5 seances of a contact heating and/or EMF. The combined action of DR and EMI, using spatially heterogenous EMF of applicator in environment of physiological hyperthermia, have had influenced mostly the inhibition of a nonlinear dynamics in CG development. Antitumoral action of DR in the animals with CG was influenced by thermal and nonthermal effects, which were initiated by spatially heterogenous EMF. Nonlinear dynamics of a CG development in animals did not depend from horizontal direction of isolines of a spatially heterogenous EMF of inductive applicator towards the tumor and duration of the irradiation procedure (15 or 30 minutes) after DR injection. The data obtained were exploited in clinical practice for the inductothermy optimal regimes elaboration while conducting complex treatment of patients, suffering oncological diseases. PMID:20825095

Orel, V E; Dziatkovs'ka, I I; Nikolov, M O; Romanov, A V; Mel'nyk, Iu H; Dziatkovs'ka, N M

2010-07-01

179

Effect of a single 30?min UMTS mobile phone-like exposure on the thermal pain threshold of young healthy volunteers.  

PubMed

One of the most frequently investigated effects of radiofrequency electromagnetic fields (RF EMFs) on the behavior of complex biological systems is pain sensitivity. Despite the growing body of evidence of EMF-induced changes in pain sensation, there is no currently accepted experimental protocol for such provocation studies for the healthy human population. In the present study, therefore, we tested the effects of third generation Universal Mobile Telecommunications System (UMTS) RF EMF exposure on the thermal pain threshold (TPT) measured on the surface of the fingers of 20 young adult volunteers. The protocol was initially validated with a topical capsaicin treatment. The exposure time was 30?min and the genuine (or sham) signal was applied to the head through a patch antenna, where RF EMF specific absorption rate (SAR) values were controlled and kept constant at a level of 1.75?W/kg. Data were obtained using randomized, placebo-controlled trials in a double-blind manner. Subjective pain ratings were tested blockwise on a visual analogue rating scale (VAS). Compared to the control and sham conditions, the results provide evidence for intact TPT but a reduced desensitization effect between repeated stimulations within the individual blocks of trials, observable only on the contralateral side for the genuine UMTS exposure. Subjective pain perception (VAS) data indicated marginally decreased overall pain ratings in the genuine exposure condition only. The present results provide pioneering information about human pain sensation in relation to RF EMF exposure and thus may contribute to cover the existing gap between safety research and applied biomedical science targeting the potential biological effects of environmental RF EMFs. PMID:23787775

Vecsei, Zsuzsanna; Csathó, Árpád; Thuróczy, György; Hernádi, István

2013-10-01

180

Experimental results for absolute cylindrical wavefront testing  

NASA Astrophysics Data System (ADS)

Applications for Cylindrical and near-cylindrical surfaces are ever-increasing. However, fabrication of high quality cylindrical surfaces is limited by the difficulty of accurate and affordable metrology. Absolute testing of such surfaces represents a challenge to the optical testing community as cylindrical reference wavefronts are difficult to produce. In this paper, preliminary results for a new method of absolute testing of cylindrical wavefronts are presented. The method is based on the merging of the random ball test method with the fiber optic reference test. The random ball test assumes a large number of interferograms of a good quality sphere with errors that are statistically distributed such that the average of the errors goes to zero. The fiber optic reference test utilizes a specially processed optical fiber to provide a clean high quality reference wave from an incident line focus from the cylindrical wave under test. By taking measurements at different rotation and translations of the fiber, an analogous procedure can be employed to determine the quality of the converging cylindrical wavefront with high accuracy. This paper presents and discusses the results of recent tests of this method using a null optic formed by a COTS cylindrical lens and a free-form polished corrector element.

Reardon, Patrick J.; Alatawi, Ayshah

2014-09-01

181

Calern Observatory absolute declinations (Martin+, 1999)  

NASA Astrophysics Data System (ADS)

A regular observational programme with a photoelectric astrolabe have been performed at ``Observatoire du Calern" (Observatoire de la Cote d'Azur, OCA, ?=+43°44'55.011"; ?=-0h27m42.44s, Calern, Caussols, France) for the last twenty years. It has been almost fully automatized between 1984 and 1987. Since 1988 the photoelectric astrolabe was used without any modification. In addition to determining the daily orientation of the local vertical, the yearly analysis of the residuals permits to derive corrections to the used star catalogue Vigouroux et al. (1992A&AS...96..477V). A global reduction method was applied for the ASPHO observations. The new form of the equations Martin & Leister (1997A&AS..126..169M) give us the possibility of using the entire set of the observing program using data taken at two zenith distances (30° and 45°). The program contains about 41648 stars' transits of 269 different stars taken at ``Observatoire du Calern" (OCA). The reduction was based on the HIPPARCOS system. We discuss the possibility of computing absolute declinations through stars belonging simultaneously to the 30° and 45° zenith distances programmes. The absolute declination corrections were determined for 185 stars with precision of 0.027" and the value of the determined equator correction is -0.018"+/-0.005". The instrumental effects were also determined. The mean epoch is 1995.29. (1 data file).

Martin, V. A. F.; Leister, N. V.; Vigouroux, G.; Furia, M.; Journet, A.

1999-05-01

182

Absolute Spectrophotometry of 237 Open Cluster Stars  

NASA Astrophysics Data System (ADS)

We present absolute spectrophotometry of 237 stars in 7 nearby open clusters: Hyades, Pleiades, Alpha Persei, Praesepe, Coma Berenices, IC 4665, and M 39. The observations were taken using the Wampler single-channel scanner (Wampler 1966) on the Crossley 0.9m telescope at Lick Observatory from July 1973 through December 1974. 21 bandpasses spanning the spectral range 3500 Angstroms to 7780 Angstroms were observed for each star, with bandwiths ranging from 32Angstroms to 64 Angstroms. Data are standardized to the Hayes--Latham (1975) system. Our measurements are compared to filter colors on the Johnson BV, Stromgren ubvy, and Geneva U V B_1 B_2 V_1 G systems, as well as to spectrophotometry of a few stars published by Gunn, Stryker & Tinsley and in the Spectrophotometric Standards Catalog (Adelman; as distributed by the NSSDC). Both internal and external comparisons to the filter systems indicate a formal statistical accuracy per bandpass of 0.01 to 0.02 mag, with apparent larger ( ~ 0.03 mag) differences in absolute calibration between this data set and existing spectrophotometry. These data will comprise part of the spectrophotometry that will be used to calibrate the Beijing-Arizona-Taipei-Connecticut Color Survey of the Sky (see separate paper by Burstein et al. at this meeting).

Clampitt, L.; Burstein, D.

1994-12-01

183

Balloon-borne infrared telescope for absolute surface photometry of the night sky  

Microsoft Academic Search

A dry ice cooled 15-cm ir telescope was used on board the balloon-borne gondola THISBE for absolute surface photometry of the Milky Way, the zodiacal light, and the airglow in the PbS wavelength region. The mechanical, optical, electronical, and thermal design of the instrument is described. The efficiency of the baffle system for suppression of stray light from earth and

W. Hofmann; D. Lemke; C. Thum

1977-01-01

184

The Seminole Serpent Warrior At Miramar, FL, Shows Settlement Locations Enabled Environmental Monitoring Reminiscent Of the Four-corners Kokopelli-like EMF Phenomena, and Related to Earthquakes, Tornados and Hurricanes.  

NASA Astrophysics Data System (ADS)

Certain Native Americans of the past seem to have correctly deduced that significant survival information for their tradition-respecting cultures resided in EMF-based phenomena that they were monitoring. This is based upon their myths and the place or cult-hero names they bequeathed us. The sites we have located in FL have been detectable by us visually, usually by faint blue light, or by the elicitation of pin-like prickings, by somewhat intense nervous-system response, by EMF interactions with aural electrochemical systems that can elicit tinitus, and other ways. In the northeast, Cautantowit served as a harbinger of Indian summer, and appears to be another alter ego of the EMF. The Miami, FL Tequesta site along the river clearly correlates with tornado, earthquake and hurricane locations. Sites like the Mohave Deserts giant man may have had similar significance.

Balam Matagamon, Chan; Pawa Matagamon, Sagamo

2004-03-01

185

Use of absolute and comparative performance feedback in absolute and comparative judgments and decisions  

Microsoft Academic Search

Which matters more—beliefs about absolute ability or ability relative to others? This study set out to compare the effects of such beliefs on satisfaction with performance, self-evaluations, and bets on future performance. In Experiment 1, undergraduate participants were told they had answered 20% correct, 80% correct, or were not given their scores on a practice test. Orthogonal to this manipulation,

Don A. Moore; William M. P. Klein

2008-01-01

186

Perceiving pitch absolutely: Comparing absolute and relative pitch possessors in a pitch memory task  

Microsoft Academic Search

BACKGROUND: The perceptual-cognitive mechanisms and neural correlates of Absolute Pitch (AP) are not fully understood. The aim of this fMRI study was to examine the neural network underlying AP using a pitch memory experiment and contrasting two groups of musicians with each other, those that have AP and those that do not. RESULTS: We found a common activation pattern for

Katrin Schulze; Nadine Gaab; Gottfried Schlaug

2009-01-01

187

Use of Absolute and Comparative Performance Feedback in Absolute and Comparative Judgments and Decisions  

ERIC Educational Resources Information Center

Which matters more--beliefs about absolute ability or ability relative to others? This study set out to compare the effects of such beliefs on satisfaction with performance, self-evaluations, and bets on future performance. In Experiment 1, undergraduate participants were told they had answered 20% correct, 80% correct, or were not given their…

Moore, Don A.; Klein, William M. P.

2008-01-01

188

Optical cryostat realizations at absolut System  

NASA Astrophysics Data System (ADS)

This paper describes two kinds of optical cryostats designed and manufactured at Absolut System. The first one makes use of pressurized LN2 for temperature control of a sample holder in the 80 K - 470 K temperature range. An optical window is implemented above the sample holder to allow for rugosity and 3D distortion of heterogeneous semicon sample assemblies on a wafer. The second one makes use of CRYOMECH remote motor type pulse tube cryocoolers for temperature control of the sample holder in the 3 K - 300 K temperature range. In this type of cryostats, particular attention has been paid to reduce the vibrations exported by the cooler. These 4 K ultra low vibration cryostats are used for characterization of samples via optical windows. Both designs will be presented and the performance reported.

Trollier, T.; Ravex, A.; Tanchon, J.

2014-01-01

189

Absolute Maximal Entanglement and Quantum Secret Sharing  

E-print Network

We study the existence of absolutely maximally entangled (AME) states in quantum mechanics and its applications to quantum information. AME states are characterized by being maximally entangled for all bipartitions of the system and exhibit genuine multipartite entanglement. With such states, we present a novel parallel teleportation protocol which teleports multiple quantum states between groups of senders and receivers. The notable features of this protocol are that (i) the partition into senders and receivers can be chosen after the state has been distributed, and (ii) one group has to perform joint quantum operations while the parties of the other group only have to act locally on their system. We also prove the equivalence between pure state quantum secret sharing schemes and AME states with an even number of parties. This equivalence implies the existence of AME states for an arbitrary number of parties based on known results about the existence of quantum secret sharing schemes.

Helwig, Wolfram; Riera, Arnau; Latorre, José I; Lo, Hoi-Kwong

2012-01-01

190

Absolute image registration for geosynchronous satellites  

NASA Technical Reports Server (NTRS)

A procedure for the absolute registration of earth images acquired by cameras on geosynchronous satellites is described. A conventional least squares process is used to estimate navigational parameters and camera pointing biases from observed minus computed landmark line and element numbers. These estimated parameters along with orbit and attitude dynamic models are used to register images, employing an automated grey-level correlation technique, inside the span represented by the landmark data. Experimental results obtained from processing the SMS-2 observation data base covering May 2, 1979 through May 20, 1979 show registration accuracies with a standard deviation of less than two pixels if the registration is within the landmark data span. It is also found that accurate registration can be expected for images obtained up to 48 hours outside of the landmark data span.

Nankervis, R.; Koch, D.; Sielski, H.; Hall, D.

1980-01-01

191

Absolute radiometric calibration of the Thematic Mapper  

NASA Technical Reports Server (NTRS)

Calibration data for the solar reflective bands of the Landsat-5 TM obtained from five in-flight absolute radiometric calibrations from July 1984-November 1985 at White Sands, New Mexico are presented and analyzed. Ground reflectance and atmospheric data were utilized to predict the spectral radiance at the entrance pupil of the TM and the average number of digital counts in each TM band. The calibration of each of the TM solar reflective bands was calculated in terms of average digital counts/unit spectral radiance for each band. It is observed that for the 12 reflectance-based measurements the rms variation from the means as a percentage of the mean is + or - 1.9 percent; for the 11 measurements in the IR bands, it is + or - 3.4 percent; and the rms variation for all 23 measurements is + or - 2.8 percent.

Slater, P. N.; Biggar, S. F.; Holm, R. G.; Jackson, R. D.; Mao, Y.

1986-01-01

192

Absolute astrometry in the next 50 years  

E-print Network

With ESA's astrometry satellite Gaia in orbit since December 2013 it is time to look at the future of fundamental astrometry and a time frame of 50 years is needed in this matter. A dozen science issues for a Gaia successor mission in twenty years are presented and in this context the possibilities for absolute astrometry with mas or sub-mas accuracies are discussed. The three powerful techniques: VLBI, the MICADO camera on the E-ELT, and the LSST are described and documented by literature references and by an extensive correspondence with leading astronomers who readily responded with all the information I needed. In brief, the two Gaia-like missions would provide an astrometric foundation for all branches of astronomy from the solar system and stellar systems to compact galaxies, quasars and dark matter by data which cannot be surpassed in the next 50 years.

Høg, Erik

2014-01-01

193

Measured and modelled absolute gravity in Greenland  

NASA Astrophysics Data System (ADS)

Present day changes in the ice volume in glaciated areas like Greenland will change the load on the Earth and to this change the lithosphere will respond elastically. The Earth also responds to changes in the ice volume over a millennial time scale. This response is due to the viscous properties of the mantle and is known as Glaical Isostatic Adjustment (GIA). Both signals are present in GPS and absolute gravity (AG) measurements and they will give an uncertainty in mass balance estimates calculated from these data types. It is possible to separate the two signals if both gravity and Global Positioning System (GPS) time series are available. DTU Space acquired an A10 absolute gravimeter in 2008. One purpose of this instrument is to establish AG time series in Greenland and the first measurements were conducted in 2009. Since then are 18 different Greenland GPS Network (GNET) stations visited and six of these are visited more then once. The gravity signal consists of three signals; the elastic signal, the viscous signal and the direct attraction from the ice masses. All of these signals can be modelled using various techniques. The viscous signal is modelled by solving the Sea Level Equation with an appropriate ice history and Earth model. The free code SELEN is used for this. The elastic signal is modelled as a convolution of the elastic Greens function for gravity and a model of present day ice mass changes. The direct attraction is the same as the Newtonian attraction and is calculated as this. Here we will present the preliminary results of the AG measurements in Greenland. We will also present modelled estimates of the direct attraction, the elastic and the viscous signals.

Nielsen, E.; Forsberg, R.; Strykowski, G.

2012-12-01

194

Issues in Absolute Spectral Radiometric Calibration: Intercomparison of Eight Sources  

NASA Technical Reports Server (NTRS)

The application of atmospheric models to AVIRIS and other spectral imaging data to derive surface reflectance requires that the sensor output be calibrated to absolute radiance. Uncertainties in absolute calibration are to be expected, and claims of 92% accuracy have been published. Measurements of accurate surface albedos and cloud absorption to be used in radiative balance calculations depend critically on knowing the absolute spectral-radiometric response of the sensor. The Earth Observing System project is implementing a rigorous program of absolute radiometric calibration for all optical sensors. Since a number of imaging instruments that provide output in terms of absolute radiance are calibrated at different sites, it is important to determine the errors that can be expected among calibration sites. Another question exists about the errors in the absolute knowledge of the exoatmospheric spectral solar irradiance.

Goetz, Alexander F. H.; Kindel, Bruce; Pilewskie, Peter

1998-01-01

195

Positioning, alignment and absolute pointing of the ANTARES neutrino telescope  

NASA Astrophysics Data System (ADS)

A precise detector alignment and absolute pointing is crucial for point-source searches. The ANTARES neutrino telescope utilises an array of hydrophones, tiltmeters and compasses for the relative positioning of the optical sensors. The absolute calibration is accomplished by long-baseline low-frequency triangulation of the acoustic reference devices in the deep-sea with a differential GPS system at the sea surface. The absolute pointing can be independently verified by detecting the shadow of the Moon in cosmic rays.

Fehr, F.; Distefano, C.; Antares Collaboration

2010-01-01

196

Absolute luminosity measurements with the LHCb detector at the LHC  

Microsoft Academic Search

Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of

R. Aaij; B. Adeva; M. Adinolfi; C. Adrover; A. Affolder; Z. Ajaltouni; J. Albrecht; F. Alessio; M. Alexander; G. Alkhazov; P. Alvarez Cartelle; A. A. Alves Jr; S. Amato; Y. Amhis; J. Anderson; R. B. Appleby; O. Aquines Gutierrez; F. Archilli; L. Arrabito; A. Artamonov; M. Artuso; E. Aslanides; G. Auriemma; S. Bachmann; J. J. Back; D. S. Bailey; V. Balagura; W. Baldini; R. J. Barlow; C. Barschel; S. Barsuk; W. Barter; A. Bates; C. Bauer; Th. Bauer; A. Bay; I. Bediaga; K. Belous; I. Belyaev; E. Ben-Haim; M. Benayoun; G. Bencivenni; S. Benson; J. Benton; R. Bernet; M van Beuzekom; A. Bien; S. Bifani; A. Bizzeti; P. M. Bjørnstad; T. Blake; F. Blanc; C. Blanks; J. Blouw; S. Blusk; A. Bobrov; V. Bocci; A. Bondar; N. Bondar; W. Bonivento; S. Borghi; A. Borgia; T. J. V. Bowcock; C. Bozzi; T. Brambach; J. van den Brand; J. Bressieux; D. Brett; S. Brisbane; M. Britsch; T. Britton; N. H. Brook; H. Brown; A. Büchler-Germann; I. Burducea; A. Bursche; J. Buytaert; S. Cadeddu; J. M. Caicedo Carvajal; O. Callot; M. Calvi; M. Calvo Gomez; A. Camboni; P. Campana; A. Carbone; G. Carboni; R. Cardinale; A. Cardini; L. Carson; K. Carvalho Akiba; G. Casse; M. Cattaneo; M. Charles; Ph. Charpentier; N. Chiapolini; K. Ciba; X. Cid Vidal; G. Ciezarek; P. E. L. Clarke; M. Clemencic; H. V. Cliff; J. Closier; C. Coca; V. Coco; J. Cogan; P. Collins; F. Constantin; G. Conti; A. Contu; A. Cook; M. Coombes; G A Cowan; R. Currie; B. D'Almagne; C. D'Ambrosio; P. David; I. De Bonis; S. De Capua; M. De Cian; F. De Lorenzi; J. M. De Miranda; L. De Paula; P. De Simone; D. Decamp; M. Deckenhoff; H. Degaudenzi; M. Deissenroth; L. Del Buono; C. Deplano; O. Deschamps; F. Dettori; J. Dickens; H. Dijkstra; P. Diniz Batista; S. Donleavy; F. Dordei; A. Dosil Suárez; D. Dossett; A. Dovbnya; F. Dupertuis; R. Dzhelyadin; C. Eames; S. Easo; U. Egede; V. Egorychev; S. Eidelman; D. van Eijk; F. Eisele; S. Eisenhardt; R. Ekelhof; L. Eklund; Ch. Elsasser; D. G. d'Enterria; D. Esperante Pereira; L. Estève; A. Falabella; E. Fanchini; C. Färber; G. Fardell; C. Farinelli; S. Farry; V. Fave; V. Fernandez Albor; M. Ferro-Luzzi; S. Filippov; C. Fitzpatrick; M. Fontana; F. Fontanelli; R. Forty; M. Frank; C. Frei; M. Frosini; S. Furcas; A. Gallas Torreira; D. Galli; M. Gandelman; P. Gandini; Y. Gao; J. C. Garnier; J. Garofoli; J. Garra Tico; L. Garrido; C. Gaspar; N. Gauvin; M. Gersabeck; T. Gershon; Ph. Ghez; V V Gligorov; C. Göbel; D. Golubkov; A. Golutvin; A. Gomes; H. Gordon; M. Grabalosa Gándara; R. Graciani Diaz; L. A. Granado Cardoso; E. Graugés; G. Graziani; A. Grecu; S. Gregson; B. Gui; E. Gushchin; Yu. Guz; T. Gys; G. Haefeli; C. Haen; S. C. Haines; T. Hampson; S. Hansmann-Menzemer; R. Harji; N. Harnew; J. Harrison; P. F. Harrison; J. He; V. Heijne; K. Hennessy; P. Henrard; J. A. Hernando Morata; E. van Herwijnen; E. Hicks; W. Hofmann; K. Holubyev; P. Hopchev; W. Hulsbergen; P. Hunt; T. Huse; R. S. Huston; D. Hutchcroft; D. Hynds; V. Iakovenko; P. Ilten; J. Imong; R. Jacobsson; A. Jaeger; M. Jahjah Hussein; E. Jans; F. Jansen; P. Jaton; B. Jean-Marie; F. Jing; M. John; D. Johnson; C. R. Jones; B. Jost; S. Kandybei; M. Karacson; T. M. Karbach; J. Keaveney; U. Kerzel; T. Ketel; A. Keune; B. Khanji; Y. M. Kim; M. Knecht; S. Koblitz; P. Koppenburg; A. Kozlinskiy; L. Kravchuk; K. Kreplin; M. Kreps; G. Krocker; P. Krokovny; F. Kruse; K. Kruzelecki; M. Kucharczyk; S. Kukulak; R. Kumar; T. Kvaratskheliya; V. N. La Thi; D. Lacarrere; G. Lafferty; A. Lai; D. Lambert; R. W. Lambert; E. Lanciotti; G. Lanfranchi; C. Langenbruch; T. Latham; R. Le Gac; J. van Leerdam; J.-P. Lees; R. Lefèvre; A. Leflat; J. Lefrançois; O. Leroy; T. Lesiak; L. Li; L. Li Gioi; M. Lieng; M. Liles; R. Lindner; C. Linn; B. Liu; G. Liu; J. H. Lopes; E. Lopez Asamar; N. Lopez-March; J. Luisier; F. Machefert; I. V. Machikhiliyan; F. Maciuc; O. Maev; J. Magnin; S. Malde; R. M. D. Mamunur; G Mancinelli; N. Mangiafave; U. Marconi; R. Märki; J. Marks; G. Martellotti; A. Martens; L. Martin; A. Martín Sánchez; D. Martinez Santos; A. Massafferri; R. Matev; Z. Mathe; C. Matteuzzi; M. Matveev; E. Maurice; B. Maynard; A. Mazurov; G. McGregor; R. McNulty; C. Mclean; M. Meissner; M. Merk; J. Merkel; R. Messi; S. Miglioranzi; D. A. Milanes; M.-N. Minard; S. Monteil; D. Moran; P. Morawski; I. Mous; F. Muheim; K. Müller; R. Muresan; B. Muryn; M. Musy; J. Mylroie-Smith; P. Naik; T. Nakada; R. Nandakumar; J. Nardulli; I. Nasteva; M Needham; N. Neufeld; C. Nguyen-Mau; M. Nicol; S. Nies; V. Niess; N. Nikitin; A. Oblakowska-Mucha; V. Obraztsov; S. Oggero; S. Ogilvy; O. Okhrimenko; R. Oldeman; M. Orlandea; J. M. Otalora Goicochea; P. Owen; B. Pal; J. Palacios; M. Palutan; J. Panman; A. Papanestis; M. Pappagallo; C J Parkinson; G. Passaleva; G. D. Patel; M. Patel; S. K. Paterson; G. N. Patrick; C Pavel-Nicorescu; A. Pazos Alvarez; A. Pellegrino; G. Penso

2011-01-01

197

Absolute nuclear material assay using count distribution (LAMBDA) space  

DOEpatents

A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

Prasad, Manoj K. (Pleasanton, CA); Snyderman, Neal J. (Berkeley, CA); Rowland, Mark S. (Alamo, CA)

2012-06-05

198

Absolute quantum energy inequalities in curved spacetime  

E-print Network

Quantum Energy Inequalities (QEIs) are results which limit the extent to which the smeared renormalised energy density of the quantum field can be negative, when averaged along a timelike curve or over a more general timelike submanifold in spacetime. On globally hyperbolic spacetimes the minimally-coupled massive quantum Klein--Gordon field is known to obey a `difference' QEI that depends on a reference state chosen arbitrarily from the class of Hadamard states. In many spacetimes of interest this bound cannot be evaluated explicitly. In this paper we obtain the first `absolute' QEI for the minimally-coupled massive quantum Klein--Gordon field on four dimensional globally hyperbolic spacetimes; that is, a bound which depends only on the local geometry. The argument is an adaptation of that used to prove the difference QEI and utilises the Sobolev wave-front set to give a complete characterisation of the singularities of the Hadamard series. Moreover, the bound is explicit and can be formulated covariantly under additional (general) conditions. We also generalise our results to incorporate adiabatic states.

Christopher J. Fewster; Calvin J. Smith

2007-02-09

199

Optimizing an Absolute Gravimeter Comparison Schedule  

NASA Astrophysics Data System (ADS)

Since 1980 various groups have executed comparisons of absolute gravimeters for the purpose of determining the accuracy of operational meters. While the final method of processing data and estimating meter accuracy has varied from comparison to comparison, one common fact has persisted - two meters can not observe gravity at both the same time and the same place. With this simple fact in mind, and despite variations in the final method of data processing, it has always been necessary to develop an efficient observation schedule for a comparison. Such a schedule must obviously depend on the number of meters in attendance and number of observing piers available. But other factors must be considered, such as how many observations each meter is required to make, how many times a meter compares to another meter and how many times a meter compares to itself - all of which effect the conditioning of the equation system. Finding the most efficient schedule with the greatest conditioning of the equation system is a problem of optimization. The number of possible combinations for even small numbers of meters and piers grows exponentially out of computational possibility if a brute force method is used. This talk discusses an efficient solution to forming such an optimized schedule, and a fast computer program which makes use of this solution.

Smith, D. A.; Saleh, J.; Eckl, M. C.

2013-12-01

200

Absolute number concentration measurement of submicrometer particles  

SciTech Connect

Condensation nuclei in the atmosphere are known to be an important factor in the development of clouds, the occurrence of rainfall, and the formation of particulate air pollutions that can cause undesirable effects on man and his environment. Condensation nuclei are invisible and numerous, and their number concentration has become the characteristic of interest and has been widely studied since the development of the first condensation nuclei counter by Aitken in 1888. A conventional nuclei counter employs the so-called condensation technique which enables the minute nuclei to grow, in a supersaturated environment, to ..mu..m-sized droplets; the number concentration of the visible droplets is then measured. Since each nucleus grows to a droplet, the number concentration of droplets and nuclei remains the same. The number of droplets is measured by (1) direct observation with a microscope (direct counter), (2) counting from photographs of the droplets (photographic counter), (3) suitably calibrated light transmission (or scattering) measurement (relative photoelectric counter). Most of the widely-used counters are relative counters in which the instrument reading must be calibrated against a direct or photographic counter. A new condensation nuclei counter is described which is designed to have the following advantages over the widely-used counters: (a) It provides an absolute concentration measurement. (b) Even a small random fluctuation of nuclei concentration can immediately be detected.

Chen, T.H.B.

1982-01-01

201

Absolute spacetime: the twentieth century ether  

E-print Network

All gauge theories need ``something fixed'' even as ``something changes.'' Underlying the implementation of these ideas all major physical theories make indispensable use of an elaborately designed spacetime model as the ``something fixed,'' i.e., absolute. This model must provide at least the following sequence of structures: point set, topological space, smooth manifold, geometric manifold, base for various bundles. The ``fine structure'' of spacetime inherent in this sequence is of course empirically unobservable directly, certainly when quantum mechanics is taken into account. This issue is at the basis of the difficulties in quantizing general relativity and has been approached in many different ways. Here we review an approach taking into account the non-Boolean properties of quantum logic when forming a spacetime model. Finally, we recall how the fundamental gauge of diffeomorphisms (the issue of general covariance vs coordinate conditions) raised deep conceptual problems for Einstein in his early development of general relativity. This is clearly illustrated in the notorious ``hole'' argument. This scenario, which does not seem to be widely known to practicing relativists, is nevertheless still interesting in terms of its impact for fundamental gauge issues.

Carl H. Brans

1998-01-09

202

Absolute radiance re-calibration of FIRST  

NASA Astrophysics Data System (ADS)

The FIRST (Far-InfraRed Spectroscopy of the Troposphere) instrument is a 10 to 100 micron spectrometer with 0.64 micron resolution designed to measure the complete mid and far-infrared radiance of the Earth's Atmosphere. FIRST has been successfully used to obtain high-quality atmospheric radiance data from the ground and from a high-altitude balloon. A Fourier transform interferometer is used to provide the spectral resolution and two on-board blackbodies are used for calibration. This paper discusses the recent re-calibration of FIRST at Space Dynamics Laboratory for absolute radiance accuracy. The calibration used the LWRICS (Long Wave Infrared Calibration Source) blackbody, which NIST testing shows to be accurate to the ~100 mK level in brightness temperature. There are several challenges to calibrating FIRST, including the large dynamic range, out of phase light, and drift in the interferogram phase. The accuracy goal for FIRST was 0.2 K over most of the 10 to 100 micron range, and results show FIRST meets this goal for a range of target temperatures.

Latvakoski, Harri; Mlynczak, Martin; Johnson, David; Cageao, Rich; Swasey, Jason; Johnson, Kendall

2012-10-01

203

Absolute and Convective Instability of a Liquid Jet  

NASA Technical Reports Server (NTRS)

The existence of absolute instability in a liquid jet has been predicted for some time. The disturbance grows in time and propagates both upstream and downstream in an absolutely unstable liquid jet. The image of absolute instability is captured in the NASA 2.2 sec drop tower and reported here. The transition from convective to absolute instability is observed experimentally. The experimental results are compared with the theoretical predictions on the transition Weber number as functions of the Reynolds number. The role of interfacial shear relative to all other relevant forces which cause the onset of jet breakup is explained.

Lin, S. P.; Hudman, M.; Chen, J. N.

1999-01-01

204

On-orbit absolute temperature calibration using multiple phase change materials: overview of recent technology advancements  

NASA Astrophysics Data System (ADS)

NASA's anticipated plan for a mission dedicated to Climate (CLARREO) will hinge upon the ability to fly SI traceable standards that provide irrefutable absolute measurement accuracy. As an example, instrumentation designed to measure spectrally resolved infrared radiances will require high-emissivity calibration blackbodies that have absolute temperature uncertainties of better than 0.045K (3 sigma). A novel scheme to provide absolute calibration of temperature sensors onorbit, that uses the transient melt signatures from multiple phase change materials, has been demonstrated in the laboratory at the University of Wisconsin and is now undergoing technology advancement under NASA Instrument Incubator Program funding. Using small quantities of phase change material (less than half of a percent of the mass of the cavity), melt temperature accuracies of better than 10 mK have been demonstrated for mercury, water, and gallium (providing calibration from 233K to 303K). Refinements currently underway focus on ensuring that the melt materials in their sealed confinement housings perform as expected in the thermal and microgravity environment of a multi-year spaceflight mission. Thermal soak and cycling tests are underway to demonstrate that there is no dissolution from the housings into the melt materials that could alter melt temperature, and that there is no liquid metal embrittlement of the housings from the metal melt materials. In addition, NASA funding has been recently secured to conduct a demonstration of this scheme in the microgravity environment of the International Space Station.

Best, Fred A.; Adler, Douglas P.; Pettersen, Claire; Revercomb, Henry E.; Perepezko, John H.

2010-11-01

205

Influence of Inner Transducer Properties on EMF Response and Stability of Solid-Contact Anion Selective Membrane Electrodes Based on Metalloporphyrin Ionophores  

PubMed Central

The performance of solid-contact/coated wire type electrodes with plasticized PVC membranes containing metalloporphyrins as anion selective ionophores is reported. The membranes are deposited on transducers based on graphite pastes and graphite rods. The hydrophobicity of the underlying conductive transducer surface is found to be a key factor that influences the formation of an aqueous layer beneath the polymer film. Elimination of this ill-defined water layer greatly improves the electrochemical properties of the ion-sensors, such as EMF stability and life-time. Only highly lipophilic electrode substrates, namely graphite paste with mineral oil, were shown to prevent the formation of aqueous layer underneath the ion-sensing membrane. The possibility of employing Co(III)-tetraphenylporphyrin both as NO2? selective ionophore and as electron/ion conducting species to ensure ion-to-electron translation was also discussed based on the results of preliminary experiments. PMID:20357903

Górski, ?ukasz; Matusevich, Alexey; Pietrzak, Mariusz; Wang, Lin; Meyerhoff, Mark E.; Malinowska, El?bieta

2010-01-01

206

New Simple Torque-Sensorless Torque Control for Quasi-Perfect Compensation of 6th Harmonic Torque Ripple Due to Nonsinusoidal Distribution of Back EMF of PMSM  

NASA Astrophysics Data System (ADS)

This paper proposes a new torque-sensorless torque control method for permanent-magnet synchronous motors (PMSMs). The proposed method can almost perfectly compensate the 6th harmonic torque ripple that is caused by the nonsinusoidal distributions of the back EMF and rotor magnetic flux of PMSMs. The torque control system is, in principle, constructed on the basis of the vector control, but has two new dedicated speed-varying devices—a harmonic torque observer and current controller. The speed-varying harmonic torque observer can estimate the harmonic component over a wide speed range, even in the case where the produced torque is constant, and generate a suitable compensating signal. The speed-varying current controller shows stable control performance over a wide speed range, it can fully track the compensated current command containing the dc and 6th harmonic components. The effectiveness of the proposed method is examined and verified through extensive numerical experiments.

Shinnaka, Shinji; Kishida, Hideo

207

Are Naturopathic Universities ``The Natural Places'' to investigate Attention-Deficit Type Disorders, with Possible Linkages to Cultural Patterns and the EMF?  

NASA Astrophysics Data System (ADS)

We desire serious investigations of behavioral impacts of certain localized or larger-scale environmental elements, such as the electromagnetic spectrum as detected by us at some sites. One author was impacted by the earth's EMF to such an extent in FL that it falsely convinced him that he was having a heart attack more severe than his nearly fatal one. Instead, it preceded an earthquake he then predicted six hours in advance. Chitto Tustenugee's `everglades' site, in Miramar FL, evokes tinnitus. Elsewhere, unease, terror, inappropriate behavior or sporadic loss of attention occurs where it can impact runway or roadway safety. Physics and Naturopathic Universities could be appropriate partners for understanding, preventing or curing these.

de Souza, Beatriz; Balam Matagamon, Chan; Pawa Matagamon, Sagamo

2006-03-01

208

Orion Absolute Navigation System Progress and Challenge  

NASA Technical Reports Server (NTRS)

The absolute navigation design of NASA's Orion vehicle is described. It has undergone several iterations and modifications since its inception, and continues as a work-in-progress. This paper seeks to benchmark the current state of the design and some of the rationale and analysis behind it. There are specific challenges to address when preparing a timely and effective design for the Exploration Flight Test (EFT-1), while still looking ahead and providing software extensibility for future exploration missions. The primary onboard measurements in a Near-Earth or Mid-Earth environment consist of GPS pseudo-range and delta-range, but for future explorations missions the use of star-tracker and optical navigation sources need to be considered. Discussions are presented for state size and composition, processing techniques, and consider states. A presentation is given for the processing technique using the computationally stable and robust UDU formulation with an Agee-Turner Rank-One update. This allows for computational savings when dealing with many parameters which are modeled as slowly varying Gauss-Markov processes. Preliminary analysis shows up to a 50% reduction in computation versus a more traditional formulation. Several state elements are discussed and evaluated, including position, velocity, attitude, clock bias/drift, and GPS measurement biases in addition to bias, scale factor, misalignment, and non-orthogonalities of the accelerometers and gyroscopes. Another consideration is the initialization of the EKF in various scenarios. Scenarios such as single-event upset, ground command, and cold start are discussed as are strategies for whole and partial state updates as well as covariance considerations. Strategies are given for dealing with latent measurements and high-rate propagation using multi-rate architecture. The details of the rate groups and the data ow between the elements is discussed and evaluated.

Holt, Greg N.; D'Souza, Christopher

2012-01-01

209

Absolute determination of local tropospheric OH concentrations  

NASA Technical Reports Server (NTRS)

Long path absorption (LPA) according to Lambert Beer's law is a method to determine absolute concentrations of trace gases such as tropospheric OH. We have developed a LPA instrument which is based on a rapid tuning of the light source which is a frequency doubled dye laser. The laser is tuned across two or three OH absorption features around 308 nm with a scanning speed of 0.07 cm(exp -1)/microsecond and a repetition rate of 1.3 kHz. This high scanning speed greatly reduces the fluctuation of the light intensity caused by the atmosphere. To obtain the required high sensitivity the laser output power is additionally made constant and stabilized by an electro-optical modulator. The present sensitivity is of the order of a few times 10(exp 5) OH per cm(exp 3) for an acquisition time of a minute and an absorption path length of only 1200 meters so that a folding of the optical path in a multireflection cell was possible leading to a lateral dimension of the cell of a few meters. This allows local measurements to be made. Tropospheric measurements have been carried out in 1991 resulting in the determination of OH diurnal variation at specific days in late summer. Comparison with model calculations have been made. Interferences are mainly due to SO2 absorption. The problem of OH self generation in the multireflection cell is of minor extent. This could be shown by using different experimental methods. The minimum-maximum signal to noise ratio is about 8 x 10(exp -4) for a single scan. Due to the small size of the absorption cell the realization of an open air laboratory is possible in which by use of an additional UV light source or by additional fluxes of trace gases the chemistry can be changed under controlled conditions allowing kinetic studies of tropospheric photochemistry to be made in open air.

Armerding, Wolfgang; Comes, Franz-Josef

1994-01-01

210

A Liquid-Helium-Cooled Absolute Reference Cold Load forLong-Wavelength Radiometric Calibration  

SciTech Connect

We describe a large (78-cm) diameter liquid-helium-cooled black-body absolute reference cold load for the calibration of microwave radiometers. The load provides an absolute calibration near the liquid helium (LHe) boiling point, accurate to better than 30 mK for wavelengths from 2.5 to 25 cm (12-1.2 GHz). The emission (from non-LHe temperature parts of the cold load) and reflection are small and well determined. Total corrections to the LHe boiling point temperature are {le} 50 mK over the operating range. This cold load has been used at several wavelengths at the South Pole and at the White Mountain Research Station. In operation, the average LHe loss rate was {le} 4.4 l/hr. Design considerations, radiometric and thermal performance and operational aspects are discussed. A comparison with other LHe-cooled reference loads including the predecessor of this cold load is given.

Bensadoun, M.; Witebsky, C.; Smoot, George F.; De Amici,Giovanni; Kogut, A.; Levin, S.

1990-05-01

211

Absolute measurement of surface and bulk absorption in DUV optics from temperature induced wavefront deformation.  

PubMed

A measurement system for quantitative determination of both surface and bulk contributions to the photo-thermal absorption in DUV optics was developed. It is based upon a Hartmann-Shack wavefront sensor with a sensitivity of ~?/10000 rms, accomplishing precise on-line monitoring of wavefront deformations of a collimated test laser beam transmitted perpendicular through the excimer laser-irradiated site of a cuboid sample. Caused by the temperature dependence of the refractive index as well as thermal expansion, the initially plane wavefront of the test laser is distorted into a cylindrical shape, with bending ends towards the surface. Sign and magnitude depend on index change and expansion. By comparison with thermal theory, this transient wavefront distortion yields a quantitative absolute measure of bulk and surface absorption losses in the sample. First rresults for fused silica are presented. PMID:20941050

Schäfer, Bernd; Schöneck, Matthias; Bayer, Armin; Mann, Klaus

2010-10-11

212

A Simple Laboratory Experiment for the Determination of Absolute Zero  

Microsoft Academic Search

A novel method that evaluates absolute zero was developed. It employs a remarkably simple and inexpensive apparatus and is based on the extrapolation of the volume of a given amount of dry air to zero volume after a volume of air trapped inside a 10-mL graduated cylinder is measured at various temperatures. This method of determining absolute zero is new

Michelle Song Kim; Suw-Young Ly

2001-01-01

213

Determination of Absolute Zero Using a Computer-Based Laboratory  

ERIC Educational Resources Information Center

We present a simple computer-based laboratory experiment for evaluating absolute zero in degrees Celsius, which can be performed in college and undergraduate physical sciences laboratory courses. With a computer, absolute zero apparatus can help demonstrators or students to observe the relationship between temperature and pressure and use…

Amrani, D.

2007-01-01

214

A vertically integrated media-isolated absolute pressure sensor  

Microsoft Academic Search

A novel, media-isolated, temperature-compensated, bulk-micromachined integrated absolute pressure sensor has successfully been developed. The sensor is usable for most applications involving exposure to harsh media, such as fuel vapor seen by manifold absolute pressure (MAP) sensors. Characterization of the device indicates that the devices fabricated meet specifications of a MAP sensor

Ken Goldman; George Gritt; Ira Baskett; K. Sooriakumar; Dan Wallace; Don Hughes; Mahesh Shah

1997-01-01

215

Automated guided vehicle with absolute encoded guide-path  

Microsoft Academic Search

An automated guided vehicle (AGV) having the ability to recover its absolute position anywhere on the guide-path is described. It uses an original guide-path encoding technique, based on the properties of pseudorandom binary sequences, resulting in a minimum code complexity of 1 bit per quantization step. An experimental AGV system was built to test the proposed absolute position measurement method

E. M. Petriu

1991-01-01

216

Absolute Model of Autonomy and Power: Toward Group Effects  

E-print Network

of Autonomy We consider an agent reacting in a rapidly changing environment and thereby consider it situated is a distinguished entity that might judge or change an agent's autonomy. This is studied under adjustable autonomy We present a model of absolute autonomy and power in agent systems. This absolute sense of autonomy

Hexmoor, Henry

217

Absolute Abundance Measurements in Solar Flares  

NASA Astrophysics Data System (ADS)

We present measurements of elemental abundances in solar flares with EVE/SDO and EIS/Hinode. EVE observes both high temperature Fe emission lines Fe XV-XXIV and continuum emission from thermal bremsstrahlung that is proportional to the abundance of H. By comparing the relative intensities of line and continuum emission it is possible to determine the enrichment of the flare plasma relative to the composition of the photosphere. This is the first ionization potential or FIP bias (F). Since thermal bremsstrahlung at EUV wavelengths is relatively insensitive to the electron temperature it is important to account for the distribution of electron temperatures in the emitting plasma. We accomplish this by using the observed spectra to infer the differential emission measure distribution and FIP bias simultaneously. In each of the 21 flares that we analyze we find that the observed composition is close to photospheric. The mean FIP bias in our sample is F=1.17+-0.22. Furthermore, we have compared the EVE measurements with corresponding flare observations of intermediate temperature S, Ar, Ca, and Fe emission lines taken with EIS. Our initial calculations also indicate a photospheric composition for these observations. This analysis suggests that the bulk of the plasma evaporated during a flare comes from deep in the chromosphere, below the region where elemental fractionation in the non-flaring corona occurs.

Warren, Harry

2014-06-01

218

Swedish Brand Ambassador to ABSOLUT ABSOLUT is looking for an experienced and highly motivated individual to build consumer  

E-print Network

individual to build consumer engagement and advocacy, to build strong and lasting relationships and excite creative-minded consumers. The ABSOLUT Ambassador will also work closely with a range of outlets and consumer influencers. In addition, the Brand Ambassador will represent ABSOLUT as a true brand champion

219

Furehter absolute paleointensity determination of welded tuffs correlated with widespread tephras: Absolute calibration of a relative paleointensity stack  

NASA Astrophysics Data System (ADS)

Widespread tephras are observed in marine sediment cores which are often correlated with oxygen isotope stratigraphy. If we obtain absolute paleointensities from welded tuffs correlated with these widespread tephras, we can correlate measured absolute paleointensities with stratigraphic positions in oxygen stratigraphy. Based on tephrochronologic correlation in oxygen isotope stratigraphy, we can compare the absolute paleointensities from the welded tuffs with a relative paleointensity stack with virtually no error in age. Mochizuki et al. (2013) reported paleointensities from welded tuffs of Aso-1, Aso-2, Aso-3 and Aso-4. Also, paleointensity data were reported for B-M polarity reversal (e.g. Chauvin et al ., 1990; Mochizuki et al., 2011), Laschamp excursion (e.g. Roperch et al., 1988; Mochizuki et al., 2006), and Iceland Basin excursion (Yamamoto et al., 2010). On the basis of 7 paleointensity data (calibration points), Mochizuki et al. (in prep.) compared these absolute paleointensity data with a relative paleointensity stack (PISO-1500; Channell et al., 2009). They suggested that relative paleointensities are linearly correlated with the absolute paleointensities. In this study, we measure absolute paleointensities from welded tuffs to increase younger and/or older paleointensity data. we will report absolute paleointensities from 14 welded tuffs (Funakura, Ito, Komagatake-i, Shikotsu-1, Kuttara-3, Ata, Kuucharo-4, Otawara, Kakuto, Shimokado, Imaichi, Yabakei, Ashino and Kumado) which have been correlated with widespread tephras. Also we will compare these absolute paleointensity data with the relative paleointensity stack.

Fujii, S.; Mochizuki, N.; Hasegawa, T.; Okada, M.; Shibuya, H.

2013-12-01

220

Absolute cross sections for ({gamma},{ital n}) transitions in lead, bismuth, and terbium  

SciTech Connect

Absolute cross sections of ({gamma},{ital n}) transitions in lead, bismuth, and terbium were measured using thermal neutron capture photons, and a high resolution neutron spectrometer. The measured ({gamma},{ital n}) cross sections were compared with predictions of the Direct-Semi-Direct (DSD) and the compound nucleus (CN) models, and were found to be generally underestimated by the DSD calculations and closer to the predictions of the CN models. Some of the ({gamma},{ital n}) cross sections in lead and bismuth were found to be comparable in magnitude to the extrapolation from the tail of the giant dipole resonance.

Birenbaum, Y.; Berant, Z.; Kahane, S.; Wolf, A. [Physics Department, Nuclear Research Center-Negev, Beer-Sheva 84190 (Israel)] [Physics Department, Nuclear Research Center-Negev, Beer-Sheva 84190 (Israel); Moreh, R. [Physics Department, Nuclear Research Center-Negev, Beer-Sheva 84190 (Israel)] [Physics Department, Nuclear Research Center-Negev, Beer-Sheva 84190 (Israel); [Ben-Gurion University, Beer-Sheva 84120 (Israel)

1995-06-01

221

Transition to Absolute Instability for (not so) Dummies  

E-print Network

These notes are intended as an elementary introduction to the concept of absolute instability. The transition from convective instability to absolute instability is an important issue when the stability of stationary flow solutions is investigated. The arguments here described were first developed in the framework of plasma physics and later applied to the hydrodynamics of mixing layers and shear flows. Far from being a comprehensive analysis of this complicated subject, the aim of these notes is just to sketch a rudimentary and quite elementary ground for physicists or engineers which have a familiarity with the basic features of linear stability in fluid dynamics, but are new to the concept of absolute instability.

Barletta, Antonio

2014-01-01

222

Temperature dependence of thermo-optical properties of fluoride glasses determined by thermal lens spectrometry  

Microsoft Academic Search

In this work we report on the use of the thermal lens spectrometry to determine the absolute values of thermal diffusivity, thermal conductivity, and temperature coefficient of optical path-length change of several fluoride glasses. The results showed that flouride glasses doped with minor quantities of Ga, In, and Zn exhibit thermal conductivities and thermal diffusivities roughly 20% larger than that

S. M. Lima; T. Catunda; R. Lebullenger; A. C. Hernandes; M. L. Baesso; A. C. Bento; L. C. M. Miranda

1999-01-01

223

Multiple Sensors for Absolute Measurement of Aerobraking Spacecraft State Estimation  

NASA Astrophysics Data System (ADS)

Prior methods to determine the spacecraft state estimation for aerobraking have been radiometric tracking data and IMU measurement. We propose a novel method for real-time absolute measurement of full state estimation based on multiple sensors.

Pigneur, B.; Ariyur, K. B.

2014-06-01

224

Absolute branching fraction measurements of exclusive D-0 semileptonic decays  

E-print Network

With the first data sample collected by the CLEO-c detector at the psi(3770) resonance we have studied four exclusive semileptonic decays of the D-0 meson. Our results include the first observation and absolute branching ...

Besson, David Zeke

2005-10-01

225

Absolute Value Boundedness, Operator Decomposition, and Stochastic Media and Equations  

NASA Technical Reports Server (NTRS)

The research accomplished during this period is reported. Published abstracts and technical reports are listed. Articles presented include: boundedness of absolute values of generalized Fourier coefficients, propagation in stochastic media, and stationary conditions for stochastic differential equations.

Adomian, G.; Miao, C. C.

1973-01-01

226

ABSENCE OF ABSOLUTELY CONTINUOUS SPECTRA FOR MULTIDIMENSIONAL SCHRODINGER OPERATORS WITH  

E-print Network

ABSENCE OF ABSOLUTELY CONTINUOUS SPECTRA FOR MULTIDIMENSIONAL SCHRODINGER OPERATORS WITH HIGH continuous spectra for multidimensional Schrodinger operators with high barriers. The result is formulated typical situations in which Schrodinger operators have singular spectrum, namely when their potential has

Stollmann, P.

227

Absolute calibration of photodetectors: photocurrent multiplication versus photocurrent subtraction  

E-print Network

We report testing of the new absolute method of photodetectors calibration based on the difference-signal measurement for two-mode squeezed vacuum by comparison with the traditional absolute method based on the coincidence counting. Using low-gain parametric down conversion we have measured the quantum efficiency of a counting detector by both methods. The difference-signal method was adapted for the counting detectors by taking into account the dead-time effect.

I. N. Agafonov; M. V. Chekhova; T. Sh. Iskhakov; A. N. Penin; G. O. Rytikov; O. A. Shumilkina

2010-12-15

228

Absolute calibration of photodetectors: photocurrent multiplication versus photocurrent subtraction  

E-print Network

We report testing of the new absolute method of photodetectors calibration based on the difference-signal measurement for two-mode squeezed vacuum by comparison with the traditional absolute method based on the coincidence counting. Using low-gain parametric down conversion we have measured the quantum efficiency of a counting detector by both methods. The difference-signal method was adapted for the counting detectors by taking into account the dead-time effect.

Agafonov, I N; Iskhakov, T Sh; Penin, A N; Rytikov, G O; Shumilkina, O A

2010-01-01

229

The Absolute Magnitude Distributions of Type IA Supernovae  

Microsoft Academic Search

The distributions of blue and visual absolute magnitudes of Type Ia supernovae (SNs Ia) are studied using distances to their parent galaxies as determined by the Tully--Fisher and surface--brightness--fluctuations techniques. The SN Ia sample is found to consist of bright events that have observational absolute magnitude dispersions of 0.3 - 0.4 mag., plus a smaller number of dim events, some

Thomas E. Vaughan; David Branch; Douglas L. Miller; Saul Perlmutter

1994-01-01

230

Absolute gravity observations during a total eclipse of the Sun.  

NASA Astrophysics Data System (ADS)

For the study of the possible variation of gravity during the total eclipse of the Sun on February 16, 1980, the authors have carried out absolute gravity measurements. A transportable absolute gravimeter made by National Institute of Metrology was used. Its accuracy of measurements is 16 ?gal. The results of observations show that there was no evident variation of gravity in the range of the accuracy of the apparatus.

Fang, Y.-Y.; Zhang, G.-Y.; Li, D.-X.; Lin, L.-G.; Lin, H.-C.; Go, Y.-G.; Gao, J.-L.; Huang, C.-Q.; Huang, D.-L.

231

A vertically integrated media-isolated absolute pressure sensor  

Microsoft Academic Search

A novel, media-isolated, temperature-compensated, bulk-micromachined integrated absolute pressure sensor has successfully been developed. The sensor is usable for most applications involving exposure to harsh media, such as fuel vapor seen by manifold absolute pressure (MAP) sensors. The device consists of two dice bonded together. Devices are batch fabricated by bonding two wafers together prior to sawing. The bottom wafer contains

K. Goldman; G. Gritt; I. Baskett; W. Czarnocki; A. Ramirez; C. Brown; D. Hughes; D. Wallace; M. Shah

1998-01-01

232

Pulsed laser diode optical fiber interferometer for absolute distance measurement  

NASA Astrophysics Data System (ADS)

An interferometry system for absolute distance measurement is described. In the system, an optical fiber Mach-Zehnder interferometer with a chirped laser diode is employed to position the measured object. Another interferometer with He-Ne laser is used to measure the optical path difference. The coherence-length of the pulsed multimode laser diode is studied. In the experiments, the system measured the absolute distance up to 1 meter with the accuracy of 2 micrometer.

Wang, Chunhe; Xiao, Hai; Hong, Haitao; Ye, Shenghua

1996-10-01

233

Absolute and Convective Instability of a Liquid Jet in Microgravity  

NASA Technical Reports Server (NTRS)

The transition from convective to absolute instability is observed in the 2.2 second drop tower of the NASA Lewis Research Center. In convective instability the disturbance grows spatially as it is convected downstream. In absolute instability the disturbance propagates both downstream and upstream, and manifests itself as an expanding sphere. The transition Reynolds numbers are determined for two different Weber numbers by use of Glycerin and a Silicone oil. Preliminary comparisons with theory are made.

Lin, Sung P.; Vihinen, I.; Honohan, A.; Hudman, Michael D.

1996-01-01

234

Spectra of absolute instruments from the WKB approximation  

NASA Astrophysics Data System (ADS)

We calculate the frequency spectra of absolute optical instruments using the Wentzel-Kramers-Brillouin (WKB) approximation. The resulting eigenfrequencies approximate the actual values very accurately; in some cases they even give the exact values. Our calculations confirm the results obtained previously by a completely different method. In particular, the eigenfrequencies of absolute instruments form tight groups that are almost equidistantly spaced. We demonstrate our method and its results applied to several examples.

Tyc, Tomáš

2013-06-01

235

ACCESS - Absolute Color Calibration Experiment for Standard Stars  

Microsoft Academic Search

ACCESS is a proposed series of rocket-borne sub-orbital missions whose purpose is to establish a network of standard stars with absolute fluxes that are directly traceable to ground based laboratory standards maintained by NIST. Our goal is to obtain an absolute spectrophotometric calibration accuracy of <1% in the 0.35-1.7 micron bandpass at a spectral resolution of greater than 500. This

M. E. Kaiser; W. V. Dixon; P. D. Feldman; J. W. Kruk; S. R. McCandliss; H. W. Moos; D. J. Sahnow; B. J. Rauscher; J. P. Gardner; R. A. Kimble; P. C. Schwartz; B. E. Woodgate; R. C. Bohlin; S. E. Deustua; R. Kurucz; S. Perlmutter

2005-01-01

236

ACCESS - Absolute Color Calibration Experiment for Standard Stars  

Microsoft Academic Search

ACCESS is a proposed series of rocket-borne sub-orbital missions whose purpose is to establish a network of standard stars with absolute fluxes that are directly traceable to ground based laboratory calibration standards maintained by NIST. Our goal is to obtain an absolute spectrophotometric calibration accuracy of <1% in the 0.35-1.7 micron bandpass at a spectral resolution of greater than 500.

Mary Elizabeth Kaiser; J. W. Kruk; S. R. McCandliss; D. J. Sahnow; W. Dixon; P. D. Feldman; H. Moos; A. Riess; B. J. Rauscher; R. A. Kimble; J. P. Gardner; B. E. Woodgate; R. C. Bohlin; S. E. Deustua; R. Kurucz; S. Perlmutter; E. L. Wright

2007-01-01

237

Relative versus absolute stimulus control in the temporal bisection task.  

PubMed

When subjects learn to associate two sample durations with two comparison keys, do they learn to associate the keys with the short and long samples (relational hypothesis), or with the specific sample durations (absolute hypothesis)? We exposed 16 pigeons to an ABA design in which phases A and B corresponded to tasks using samples of 1 s and 4 s, or 4 s and 16 s. Across phases, we varied the mapping between the samples and the keys. For group Relative, short and long samples were always associated with the same keys (e.g., Phase A: '1s? Left, 4s? Right'; Phase B: '4s? Left, 16s? Right'); for group Absolute, the 4-s sample was associated always with the same key (e.g., Phase A: '1s? Left, 4s? Right'; Phase B: '16s? Left, 4s? Right'). If temporal control is relational, group Relative should learn the new task faster than group Absolute, but if temporal control is absolute, the opposite should occur. We compared the results with the predictions of the Learning-to-Time (LeT) model, which accounts for temporal discrimination in terms of absolute stimulus control and stimulus generalization. The acquisition curves of the two groups were generally consistent with LeT and therefore more consistent with the absolute than the relative hypothesis. PMID:22851790

Pinheiro de Carvalho, Marilia; Machado, Armando

2012-07-01

238

Revisiting absolute and relative judgments in the WITNESS model.  

PubMed

The WITNESS model (Clark in Applied Cognitive Psychology 17:629-654, 2003) provides a theoretical framework with which to investigate the factors that contribute to eyewitness identification decisions. One key factor involves the contributions of absolute versus relative judgments. An absolute contribution is determined by the degree of match between an individual lineup member and memory for the perpetrator; a relative contribution involves the degree to which the best-matching lineup member is a better match to memory than the remaining lineup members. In WITNESS, the proportional contributions of relative versus absolute judgments are governed by the values of the decision weight parameters. We conducted an exploration of the WITNESS model's parameter space to determine the identifiability of these relative/absolute decision weight parameters, and compared the results to a restricted version of the model that does not vary the decision weight parameters. This exploration revealed that the decision weights in WITNESS are difficult to identify: Data often can be fit equally well by setting the decision weights to nearly any value and compensating with a criterion adjustment. Clark, Erickson, and Breneman (Law and Human Behavior 35:364-380, 2011) claimed to demonstrate a theoretical basis for the superiority of lineup decisions that are based on absolute contributions, but the relationship between the decision weights and the criterion weakens this claim. These findings necessitate reconsidering the role of the relative/absolute judgment distinction in eyewitness decision making. PMID:23943556

Fife, Dustin; Perry, Colton; Gronlund, Scott D

2014-04-01

239

A New Approach For Absolute Temperature Calibration: Application to the CLARREO Mission  

NASA Astrophysics Data System (ADS)

A novel scheme to provide on-orbit absolute calibration of blackbody temperature sensors (on-demand) has been demonstrated using a copy of the engineering model version of a space flight hardware blackbody design (GIFTS). The scheme uses the phase change signature of reference materials to assign an absolute temperatures scale to the blackbody sensors over a large temperature range. Uncertainties of better than 0.020 K have been demonstrated over the temperature range from 234 to 303 K. Thermal modeling has been conducted to optimize the design, and to show that accuracies comparable to those measured in the laboratory should be obtainable in the less-controlled on-orbit temperature environment. The implementation if this scheme is very attractive due to its simplicity and relatively low mass. In addition, all aspects of the electronics (control and temperature readout) needed to support this scheme have been developed and demonstrated in the as-delivered GIFTS Engineering Model blackbody calibration system developed by the University of Wisconsin. NASA's anticipated plan for a mission dedicated to Climate (CLARREO) will hinge upon the ability to fly absolute standards that can provide the basis to meet stringent requirements on measurement accuracy. For example, instrumentation designed to measure spectrally resolved infrared radiances will require high-emissivity calibration blackbodies having absolute temperature uncertainties of better than 0.020 K (3 sigma). The novel blackbody temperature calibration scheme described here is very well suited for the CLARREO mission because if its low mass, high accuracy, and ease of implementation into a demonstrated flight blackbody design.

Best, F. A.; Adler, D. P.; Ellington, S. D.; Thielman, D. J.; Revercomb, H. E.; Anderson, J. G.

2007-12-01

240

Electron-Transport in Calcium-Based Metallic Glasses  

E-print Network

- perature, by a computer which also monitored and record- ed the thermal electromotive force (EMF). During this procedure the temperature of the 1-K plate was held con- stant by a temperature controller. The absolute temperature of each copper block... on the thermopower stage and the temperature difference be- tween them were measured with Au-(0.07-at. %) Fe versus Chromel thermocouples which were calibrated against a Ge-resistance thermometer and a Pt-resistance thermome- ter. The thermocouple EMF's were...

Naugle, Donald G.; DELGADO, R.; ARMBRUSTER, H.; TSAI, CL; CALLAWAY, TO; REYNOLDS, D.; MORUZZI, VL.

1986-01-01

241

Thermodynamic data from redox reactions at high temperatures. III. Activity-composition relations in Ni-Pd alloys from EMF measurements at 850–1250 K, and calibration of the NiO+Ni-Pd assemblage as a redox sensor  

Microsoft Academic Search

The assemblage NiO+Ni-Pd alloy has been calibrated as a precise oxygen fugacity sensor in the temperature range 850–1250 K at 1 bar, using an electrochemical technique with oxygen-specific CSZ electrolytes, and Ni+NiO and Cu+Cu2O as the reference electrodes. Nine compositions were studied, ranging from 0.12 to 0.83 XNialloy. Steady EMFs, implying equilibrium, were rapidly achieved in all cells, and were

Mark I. Pownceby; Hugh St. C. O'Neill

1994-01-01

242

The Seminole Serpent Warrior At Miramar, FL, Shows Settlement Locations Enabled Environmental Monitoring Reminiscent Of the Four-corners Kokopelli-like EMF Phenomena, and Related to Earthquakes, Tornados and Hurricanes  

Microsoft Academic Search

Certain Native Americans of the past seem to have correctly deduced that significant survival information for their tradition-respecting cultures resided in EMF-based phenomena that they were monitoring. This is based upon their myths and the place or cult-hero names they bequeathed us. The sites we have located in FL have been detectable by us visually, usually by faint blue light,

Chan Balam Matagamon; Sagamo Pawa Matagamon

2004-01-01

243

Electron transfer from laser excited rydberg atoms to molecules. Absolute rate constants at low and intermediate principal quantum numbers  

Microsoft Academic Search

Using mass spectrometric detection of positive and negative ions, we have investigated ionizing reactions of Ne(ns,nd) Rydberg atoms, efficiently excited by resonant two-photon excitation of metastable Ne(3s3P2) atoms, with electron attaching moleculesBC (BC=SF6, CCl4, CS2, O2) at thermal collision energies. Absolute rate constants have been determined in the range of low and intermediate principal quantum numbersn(5?n?30) by utilizing the photoionization

K. Harth; M.-W. Ruf; H. Hotop

1989-01-01

244

On-Orbit Absolute Temperature Calibration Using Multiple Phase Change Materials  

NASA Astrophysics Data System (ADS)

NASA’s anticipated plan for a mission dedicated to Climate (CLARREO) will hinge upon the ability to fly SI traceable standards that provide irrefutable absolute measurement accuracy. As an example, instrumentation designed to measure spectrally resolved infrared radiances will require high-emissivity calibration blackbodies that have absolute temperature uncertainties of better than 0.045K (3 sigma). A novel scheme to provide absolute calibration of temperature sensors, suitable for CLARREO on-orbit operation, has been demonstrated in the laboratory at the University of Wisconsin, and is now undergoing refinement under NASA Instrument Incubator Program funding. In this scheme, small quantities of reference materials (mercury, water, and gallium) are imbedded into the blackbody cavity wall, in a manner similar to the temperature sensors to be calibrated. As the blackbody cavity is slowly heated through the melt point of each reference material, the transient temperature signature from the imbedded thermistor sensors provides a very accurate indication of the melt temperature. Using small quantities of phase change material (less than half of a percent of the mass of the cavity), melt temperature accuracies of better than 10 mK have been demonstrated for mercury, water, and gallium (providing calibration from 233K to 303K). Refinements currently underway focus on ensuring that the melt materials in their sealed confinement housings perform as expected in the thermal and microgravity environment of a multi-year spaceflight mission. Thermal soak and cycling tests are underway to demonstrate that there is no dissolution from the housings into the melt materials that could alter melt temperature, and that there is no liquid metal embrittlement of the housings from the metal melt materials. In addition, NASA funding has been recently secured to conduct a demonstration of this scheme in the microgravity environment of the International Space Station.

Best, F. A.; Adler, D. P.; Pettersen, C.; Revercomb, H. E.; Perepezko, J. H.

2009-12-01

245

Absolute stability of a class of trilateral haptic systems.  

PubMed

Trilateral haptic systems can be modeled as three-port networks. We present a criterion for absolute stability of a general class of three-port networks. Traditionally, existing (i.e., Llewellyn's) criteria have facilitated the stability analysis of bilateral haptic systems modeled as two-port networks. If the same criteria were to be used for stability analysis of a three-port network, its third port termination would need to be assumed known for it to reduce to a two-port network. This is restrictive because, for absolute stability, all three terminations of the three-port network must be allowed to be arbitrary (while passive). Extending Llewellyn's criterion, we present closed-form necessary and sufficient conditions for absolute stability of a general class of three-port networks. We first find a symmetrization condition under which a general asymmetric impedance (or admittance) matrix Z3 × 3 has a symmetric equivalent Zeq from a network stability perspective. Then, via the equivalence of passivity and absolute stability for reciprocal networks, an absolute stability condition for the original nonreciprocal network is derived. To demonstrate the convenience and utility of using this criterion for both analysis and design, it is applied to the problem of designing stabilizing controllers for dual-user haptic teleoperation systems, with simulations and experiments validating the criterion. PMID:25248167

Li, Jian; Tavakoli, Mahdi; Huang, Qi

2014-01-01

246

Absolute Neutron Emission Measurement in Burning Plasma Experiments  

SciTech Connect

The absolute measurement of neutron emission rate from the whole plasma is a very important diagnostics as a fusion power monitor in fusion experimental devices with D-T or D-T operations. Here measurement techniques of time-resolved and time-integrated absolute neutron emission on the present tokamaks and ITER are reviewed. In the present tokamaks, fission chamber installed outside the vacuum vessel are very popular in the absolute neutron emission rate measurement. As well as conventional neutron monitors installed outside the vacuum vessel, in-vessel neutron monitors using micro fission chamber are proposed for the absolute neutron emission rate measurement in ITER. The neutron activation system provides time-integrated measurements of the total neutron yield with high accuracy by using well known neutron reaction cross sections, which is useful to maintain a robust measure of fusion energy production with stability and wide dynamic range. The calibration of the relation between the neutron emission rate in the whole plasma and the output of neutron monitor is the most important issue in the absolute neutron emission rate measurements. The calibration of the neutron detectors has been performed by moving a neutron source such as a {sup 252}Cf neutron or a small accelerator-based neutron generator. For the calibration in ITER, the neutron generator with neutron emission rate of 10{sup 11} s{sup -1} or stronger is required to obtain high accuracy.

Nishitani, Takeo; Ishikawa, Masao; Kondoh, Takashi; Kusama, Yoshinori [Japan Atomic Energy Agency, Naka, Ibaraki-ken, 311-0193 (Japan); Asai, Keisuke [Nagoya University, Chikusa-ku, Nagoya, 464-8603 (Japan); Sasao, Mmamiko [Tohoku University, Aoba-ku, Sendai, 980-8579 (Japan)

2008-03-12

247

Absolute irradiance of the Moon for on-orbit calibration  

USGS Publications Warehouse

The recognized need for on-orbit calibration of remote sensing imaging instruments drives the ROLO project effort to characterize the Moon for use as an absolute radiance source. For over 5 years the ground-based ROLO telescopes have acquired spatially-resolved lunar images in 23 VNIR (Moon diameter ???500 pixels) and 9 SWIR (???250 pixels) passbands at phase angles within ??90 degrees. A numerical model for lunar irradiance has been developed which fits hundreds of ROLO images in each band, corrected for atmospheric extinction and calibrated to absolute radiance, then integrated to irradiance. The band-coupled extinction algorithm uses absorption spectra of several gases and aerosols derived from MODTRAN to fit time-dependent component abundances to nightly observations of standard stars. The absolute radiance scale is based upon independent telescopic measurements of the star Vega. The fitting process yields uncertainties in lunar relative irradiance over small ranges of phase angle and the full range of lunar libration well under 0.5%. A larger source of uncertainty enters in the absolute solar spectral irradiance, especially in the SWIR, where solar models disagree by up to 6%. Results of ROLO model direct comparisons to spacecraft observations demonstrate the ability of the technique to track sensor responsivity drifts to sub-percent precision. Intercomparisons among instruments provide key insights into both calibration issues and the absolute scale for lunar irradiance.

Stone, T.C.; Kieffer, H.H.

2002-01-01

248

Absolute-structure determination: past, present and future.  

PubMed

Single-crystal X-ray crystallography is the major analytical technique in use today for absolute-configuration determination. The origins of absolute-structure determination, starting from Friedel's 1913 proof that the intensities of the opposites hkl and hkl are identical, are traced. The important structural principles derived from the study of chiral, but pseudo-mirror symmetric, methyprylon are described. For the present time, the use of the average and difference intensities of the opposites hkl and hkl are stressed. This leads to the use of Friedif, of 2 AD and selected D plots, of Rmerge and the D-Patterson. The best techniques for absolute-structure determination in the future are described. Some advice to the scientific community concludes the paper. PMID:24801693

Flack, Howard D

2014-01-01

249

Method and apparatus for two-dimensional absolute optical encoding  

NASA Technical Reports Server (NTRS)

This invention presents a two-dimensional absolute optical encoder and a method for determining position of an object in accordance with information from the encoder. The encoder of the present invention comprises a scale having a pattern being predetermined to indicate an absolute location on the scale, means for illuminating the scale, means for forming an image of the pattern; and detector means for outputting signals derived from the portion of the image of the pattern which lies within a field of view of the detector means, the field of view defining an image reference coordinate system, and analyzing means, receiving the signals from the detector means, for determining the absolute location of the object. There are two types of scale patterns presented in this invention: grid type and starfield type.

Leviton, Douglas B. (Inventor)

2004-01-01

250

Absolute measurement of femtosecond pump-probe signal strength.  

PubMed

The absolute femtosecond pump-probe signal strength of deprotonated fluorescein in basic methanol is measured. Calculations of the absolute pump-probe signal based on the steady-state absorption and emission spectrum that use only independently measured experimental parameters are carried out. The calculation of the pump-probe signal strength assumes the pump and probe fields are both weak and includes the following factors: the transverse spatial profile of the laser beams; the pulse spectra; attenuation of the propagating pulses with depth in the sample; the anisotropic transition probability for polarized light; and time-dependent electronic population relaxation. After vibrational and solvent relaxation are complete, the calculation matches the measurement to within 10% error without any adjustable parameters. This demonstrates quantitative measurement of absolute excited state population. PMID:23713582

Cho, Byungmoon; Tiwari, Vivek; Hill, Robert J; Peters, William K; Courtney, Trevor L; Spencer, Austin P; Jonas, David M

2013-07-25

251

Method for estimating absolute lung volumes at constant inflation pressure.  

PubMed

A method has been devised for measuring functional residual capacity in the intact killed animal or absolute lung volumes in any excised lung preparation without changing the inflation pressure. This is achieved by titrating the absolute pressure of a chamber in which the preparation is compressed until a known volume of air has entered the lungs. This technique was used to estimate the volumes of five intact rabbit lungs and five rigid containers of known dimensions by means of Boyle's law. Results were found to agree to within +/- 1% with values determined by alternative methods. In the discussion the advantage of determining absolute lung volumes at almost any stage in a study of lung mechanics without the determination itself changing inflation pressure and, hence, lung volume is emphasized. PMID:511699

Hills, B A; Barrow, R E

1979-10-01

252

The absolute motion of the peculiar cluster NGC6791  

E-print Network

We present improved values of the three components of the absolute space velocity of the open cluster NGC6791. One HST ACS/WFC field with two-epoch observations provides astrometric measurements of objects in a field containing the cluster center. Identification of 60 background galaxies with sharp nuclei allows us to determine an absolute reference point, and measure the absolute proper motion of the cluster. We find (mu_alpha cos(delta), mu_delta)_J2000.0 = (-0.57+/-0.13, -2.45+/-0.12)mas/yr, and adopt V_rad = -47.1+/-0.7km/s from the average of the published values. Assuming a Galactic potential, we calculate the Galactic orbit of the cluster for various assumed distances, and briefly discuss the implications on the nature and the origin of this peculiar cluster.

L. R. Bedin; G. Piotto; G. Carraro; I. R. King; J. Anderson

2006-10-18

253

Characterization of Fundamental Luminescence Properties of the Mars Soil Simulant JSC Mars1 and Their Relevance to Absolute Dating of Martian Eolian Sediments  

Microsoft Academic Search

This report explores the potential for luminescence dating techniques to provide absolute age determinations of eolian sediments on the surface of Mars, including those incorporated in the martian polar ice caps. Fundamental thermally and optically stimulated luminescence properties of bulk samples of JSC Mars-1 soil simulant are reported and their relevance to the development of dating procedures is discussed. The

Kenneth Lepper; Stephen W. S. McKeever

2000-01-01

254

Stability comparison of two absolute gravimeters: optical versus atomic interferometers  

E-print Network

We report the direct comparison between the stabilities of two mobile absolute gravimeters of different technology: the LNE-SYRTE Cold Atom Gravimeter and FG5X\\#216 of the Universit\\'e du Luxembourg. These instruments rely on two different principles of operation: atomic and optical interferometry. The comparison took place in the Walferdange Underground Laboratory for Geodynamics in Luxembourg, at the beginning of the last International Comparison of Absolute Gravimeters, ICAG-2013. We analyse a 2h10 duration common measurement, and find that the CAG shows better immunity with respect to changes in the level of vibration noise, as well as a slightly better short term stability.

Gillot, Pierre; Landragin, Arnaud; Santos, Franck Pereira Dos; Merlet, Sébastien

2014-01-01

255

Absolute branching fraction measurements of exclusive D+ semileptonic decays.  

PubMed

Using data collected at the psi(3770) resonance with the CLEO-c detector at the Cornell e+e- storage ring, we present improved measurements of the absolute branching fractions of D+decays to K0e+ve, pi0e+ve, K*0e+ve, and p0e+ve, and the first observation and absolute branching fraction measurement of D+ --> omega e+ve. We also report the most precise tests to date of isospin invariance in semileptonic D0 and D+ decays. PMID:16383892

Huang, G S; Miller, D H; Pavlunin, V; Sanghi, B; Shipsey, I P J; Adams, G S; Chasse, M; Cravey, M; Cummings, J P; Danko, I; Napolitano, J; He, Q; Muramatsu, H; Park, C S; Park, W; Thorndike, E H; Coan, T E; Gao, Y S; Liu, F; Artuso, M; Boulahouache, C; Blusk, S; Butt, J; Dambasuren, E; Dorjkhaidav, O; Li, J; Menaa, N; Mountain, R; Nandakumar, R; Randrianarivony, K; Redjimi, R; Sia, R; Skwarnicki, T; Stone, S; Wang, J C; Zhang, K; Csorna, S E; Bonvicini, G; Cinabro, D; Dubrovin, M; Briere, R A; Chen, G P; Chen, J; Ferguson, T; Tatishvili, G; Vogel, H; Watkins, M E; Rosner, J L; Adam, N E; Alexander, J P; Berkelman, K; Cassel, D G; Crede, V; Duboscq, J E; Ecklund, K M; Ehrlich, R; Fields, L; Gibbons, L; Gittelman, B; Gray, R; Gray, S W; Hartill, D L; Heltsley, B K; Hertz, D; Hsu, L; Jones, C D; Kandaswamy, J; Kreinick, D L; Kuznetsov, V E; Mahlke-Krüger, H; Meyer, T O; Onyisi, P U E; Patterson, J R; Peterson, D; Phillips, E A; Pivarski, J; Riley, D; Ryd, A; Sadoff, A J; Schwarthoff, H; Shi, X; Shepherd, M R; Stroiney, S; Sun, W M; Urner, D; Weaver, K M; Wilksen, T; Weinberger, M; Athar, S B; Avery, P; Breva-Newell, L; Patel, R; Potlia, V; Stoeck, H; Yelton, J; Rubin, P; Cawlfield, C; Eisenstein, B I; Gollin, G D; Karliner, I; Kim, D; Lowrey, N; Naik, P; Sedlack, C; Selen, M; Williams, J; Wiss, J; Edwards, K W; Besson, D; Pedlar, T K; Cronin-Hennessy, D; Gao, K Y; Gong, D T; Hietala, J; Kubota, Y; Klein, T; Lang, B W; Li, S Z; Poling, R; Scott, A W; Smith, A; Dobbs, S; Metreveli, Z; Seth, K K; Tomaradze, A; Zweber, P; Ernst, J; Mahmood, A H; Severini, H; Asner, D M; Dytman, S A; Love, W; Mehrabyan, S; Mueller, J A; Savinov, V; Li, Z; Lopez, A; Mendez, H; Ramirez, J

2005-10-28

256

Non-Invasive Method of Determining Absolute Intracranial Pressure  

NASA Technical Reports Server (NTRS)

A method is presented for determining absolute intracranial pressure (ICP) in a patient. Skull expansion is monitored while changes in ICP are induced. The patient's blood pressure is measured when skull expansion is approximately zero. The measured blood pressure is indicative of a reference ICP value. Subsequently, the method causes a known change in ICP and measured the change in skull expansion associated therewith. The absolute ICP is a function of the reference ICP value, the known change in ICP and its associated change in skull expansion; and a measured change in skull expansion.

Yost, William T. (Inventor); Cantrell, John H., Jr. (Inventor); Hargens, Alan E. (Inventor)

2004-01-01

257

Stability comparison of two absolute gravimeters: optical versus atomic interferometers  

NASA Astrophysics Data System (ADS)

We report the direct comparison between the stabilities of two mobile absolute gravimeters of different technology: the LNE-SYRTE Cold Atom Gravimeter (CAG) and FG5X#216 of the Université du Luxembourg. These instruments rely on two different principles of operation: atomic and optical interferometry. The comparison took place in the Walferdange Underground Laboratory for Geodynamics in Luxembourg, at the beginning of the last International Comparison of Absolute Gravimeters, ICAG-2013. We analyse a 2h10 duration common measurement, and find that the CAG shows better immunity with respect to changes in the level of vibration noise, as well as a slightly better short term stability.

Gillot, P.; Francis, O.; Landragin, A.; Pereira Dos Santos, F.; Merlet, S.

2014-10-01

258

Absolute integrated intensity for the nu-1 sulfur dioxide band  

NASA Technical Reports Server (NTRS)

The absolute integrated intensity of the IR vibration-rotation nu-1 SO2 band was measured using the linear portion of the curve of growth. Infrared spectroscopic-absorption cell measurements were performed on sulfur dioxide at partial pressures less than 0.15 torr with nitrogen added to give a total pressure of 705 torr, the path length being 4 mm. The absolute integrated intensity was determined to be 112.0 plus or minus 2.6/cm/sq (atm cm) at 296 K at the 95% confidence level.

Pilon, P. J.; Young, C.

1976-01-01

259

Nonexistence of equilibrium states at absolute negative temperatures  

NASA Astrophysics Data System (ADS)

We show that states of macroscopic systems with purported absolute negative temperatures are not stable under small, yet arbitrary, perturbations. We prove the previous statement using the fact that, in equilibrium, the entropy takes its maximum value. We discuss that, while Ramsey theoretical reformulation of the second law for systems with negative temperatures is logically correct, it must be a priori assumed that those states are in thermodynamic equilibrium. Since we argue that those states cannot occur, reversible processes are impossible, and, thus, Ramsey identification of absolute negative temperatures is untenable.

Romero-Rochín, Víctor

2013-08-01

260

Perceiving pitch absolutely: Comparing absolute and relative pitch possessors in a pitch memory task  

PubMed Central

Background The perceptual-cognitive mechanisms and neural correlates of Absolute Pitch (AP) are not fully understood. The aim of this fMRI study was to examine the neural network underlying AP using a pitch memory experiment and contrasting two groups of musicians with each other, those that have AP and those that do not. Results We found a common activation pattern for both groups that included the superior temporal gyrus (STG) extending into the adjacent superior temporal sulcus (STS), the inferior parietal lobule (IPL) extending into the adjacent intraparietal sulcus (IPS), the posterior part of the inferior frontal gyrus (IFG), the pre-supplementary motor area (pre-SMA), and superior lateral cerebellar regions. Significant between-group differences were seen in the left STS during the early encoding phase of the pitch memory task (more activation in AP musicians) and in the right superior parietal lobule (SPL)/intraparietal sulcus (IPS) during the early perceptual phase (ITP 0–3) and later working memory/multimodal encoding phase of the pitch memory task (more activation in non-AP musicians). Non-significant between-group trends were seen in the posterior IFG (more in AP musicians) and the IPL (more anterior activations in the non-AP group and more posterior activations in the AP group). Conclusion Since the increased activation of the left STS in AP musicians was observed during the early perceptual encoding phase and since the STS has been shown to be involved in categorization tasks, its activation might suggest that AP musicians involve categorization regions in tonal tasks. The increased activation of the right SPL/IPS in non-AP musicians indicates either an increased use of regions that are part of a tonal working memory (WM) network, or the use of a multimodal encoding strategy such as the utilization of a visual-spatial mapping scheme (i.e., imagining notes on a staff or using a spatial coding for their relative pitch height) for pitch information. PMID:19712445

2009-01-01

261

Weighted Least Absolute Value state estimation using interior point methods  

Microsoft Academic Search

This paper addresses the application of interior point methods to the Weighted Least Absolute Value state estimation problem. Interior point methods are applied to the primal and dual formulations of the problem. The dual formulation involves solving least squares problems identical in structure to those used in conventional Weighted Least Squares state estimation. The dual formulation also provides an initial

H. Singh; F. L. Alvarado

1994-01-01

262

Series that Converge Absolutely but Don't Converge  

ERIC Educational Resources Information Center

If a series of real numbers converges absolutely, then it converges. The usual proof requires completeness in the form of the Cauchy criterion. Failing completeness, the result is false. We provide examples of rational series that illustrate this point. The Cantor set appears in connection with one of the examples.

Kantrowitz, Robert; Schramm, Michael

2012-01-01

263

Error propagation in absolute geodetic networks a continuous approach  

Microsoft Academic Search

Summary Studies of error propagation in geodetic networks of an absolute type have already been carried through by several authors using various mathematical techniques. The geodetic elasticity theory relies on a continuation of the actual, discrete network. The traditional observation and normal equation matrices are substituted by partial differential equations with corresponding boundary conditions. The continuous approach only reflects the

Kai Borre; L. Kubácek

1978-01-01

264

Urey: to measure the absolute age of Mars  

NASA Technical Reports Server (NTRS)

UREY, a proposed NASA Mars Scout mission will, for the first time, measure the absolute age of an identified igneous rock formation on Mars. By extension to relatively older and younger rock formations dated by remote sensing, these results will enable a new and better understanding of Martian geologic history.

Randolph, J. E.; Plescia, J.; Bar-Cohen, Y.; Bartlett, P.; Bickler, D.; Carlson, R.; Carr, G.; Fong, M.; Gronroos, H.; Guske, P. J.; Herring, M.; Javadi, H.; Johnson, D. W.; Larson, T.; Malaviarachchi, K.; Sherrit, S.; Stride, S.; Trebi-Ollennu, A.; Warwick, R.

2003-01-01

265

Relative versus Absolute Stimulus Control in the Temporal Bisection Task  

ERIC Educational Resources Information Center

When subjects learn to associate two sample durations with two comparison keys, do they learn to associate the keys with the short and long samples (relational hypothesis), or with the specific sample durations (absolute hypothesis)? We exposed 16 pigeons to an ABA design in which phases A and B corresponded to tasks using samples of 1 s and 4 s,…

de Carvalho, Marilia Pinhiero; Machado, Armando

2012-01-01

266

Fabricating the Absolute Fake : America in Contemporary Pop Culture  

Microsoft Academic Search

Onze wereld wordt gedomineerd door de Amerikaanse popcultuur. Fabricating the Absolute Fake onderzoekt de dynamiek van Amerikanisering aan de hand van hedendaagse films, televisieprogramma's en popsterren die reflecteren op de vraag wat het betekent om Amerikaan in een mondiale popcultuur te zijn. Jaap Kooijman analyseert zowel Amerikaanse popcultuur (Oprah Winfrey, Ally McBeal, Michael Jackson) als Nederlandse populaire cultuur (Ali B.,

Jaap Kooijman

2008-01-01

267

Islamic Star Patterns in Absolute Geometry CRAIG S. KAPLAN  

E-print Network

master to apprentice and ultimately lost in history [Abas and Salman 1992]. The quest to design star on the axioms of absolute geometry for exploring the design space of Islamic star patterns. Our approach makes created by Najm can be designed equally well to fit the Euclidean plane, the hyperbolic plane

Washington at Seattle, University of

268

The absolute infrared magnitudes of type Ia supernovae  

Microsoft Academic Search

The absolute luminosities and homogeneity of early-time infrared (IR) light curves of type Ia supernovae are examined. Eight supernovae are considered. These are selected to have accurately known epochs of maximum blue light as well as having reliable distance estimates and\\/or good light curve coverage. Two approaches to extinction correction are considered. Owing to the low extinction in the IR,

W. P. S. Meikle

2000-01-01

269

From discrete to absolutely continuous solutions of indeterminate moment problems  

E-print Network

to the same moment problems. The follow­ ing cases are considered: log­normal, generalized Stieltjes ­WigertFrom discrete to absolutely continuous solutions of indeterminate moment problems Christian Berg­known that the set V of solutions to the corresponding moment problem contains discrete measures as well

Berg, Christian

270

From discrete to absolutely continuous solutions of indeterminate moment problems  

E-print Network

to the same moment problems. The follow- ing cases are considered: log-normal, generalized Stieltjes sequence, it is well-known that the set V of solutions to the corresponding moment problem contains From discrete to absolutely continuous solutions of indeterminate moment

Berg, Christian

271

Absolute Pitch: Effects of Timbre on Note-Naming Ability  

Microsoft Academic Search

Background: Absolute pitch (AP) is the ability to identify or produce isolated musical tones. It is evident primarily among individuals who started music lessons in early childhood. Because AP requires memory for specific pitches as well as learned associations with verbal labels (i.e., note names), it represents a unique opportunity to study interactions in memory between linguistic and nonlinguistic information.

Patrícia Vanzella; E. Glenn Schellenberg; Dorothy Bishop

2010-01-01

272

Absolute negative conductivity of graphene with impurities in magnetic field  

SciTech Connect

Current-voltage and current-field characteristics for graphene with Anderson interaction of conduction and impurity electrons are calculated by the 'average electron' method in the case of low temperatures. These characteristics are analyzed depending on the frequency of an external ac electric field and a magnetic field. A portion with absolute negative conductivity is detected.

Belonenko, M. B. [Volgograd Institute of Business, Laboratory of Nanotechnologies (Russian Federation); Lebedev, N. G.; Yanyushkina, N. N., E-mail: yana@inbox.ru [Volgograd State University (Russian Federation); Shakirzyanov, M. M. [Russian Academy of Sciences, Zavoisky Physicotechnical Institute, Kazan Scientific Center (Russian Federation)

2011-05-15

273

Absolute Calibration of a Large-diameter Light Source  

E-print Network

A method of absolute calibration for large aperture optical systems is presented, using the example of the Pierre Auger Observatory fluorescence detectors. A 2.5 m diameter light source illuminated by an ultra--violet light emitting diode is calibrated with an overall uncertainty of 2.1 % at a wavelength of 365 nm.

Brack, J T; Dorofeev, A; Gookin, B; Harton, J L; Petrov, Y; Rovero, A C

2013-01-01

274

An inverse method for estimating absolute velocities of the Kuroshio  

Microsoft Academic Search

An inverse method for estimating absolute velocities of the Kuroshio in the East China Sea and south of Japan was applied using hydrographic section data collected from January 19 to February 27 2006. By assuming the water mass to be conserved in four computational boxes, an undetermined system of linear equations was built. A family of solutions was firstly obtained

Bo Li; Xiao-Hua Zhu

2011-01-01

275

The Absolute Thermoelectric Power of Some Dilute Liquid Sodium Alloys  

Microsoft Academic Search

The absolute thermoelectric powers of liquid sodium and of dilute liquid alloys of sodium with silver, cadmium, indium and tin have been measured within the temperature range 100–460°C. The thermopower of liquid sodium is decreased by the addition of cadmium, indium or tin, with cadmium having the smallest and indium the greatest effect, whereas it is increased slightly on the

H. A. Davies

1969-01-01

276

The Absolute Field Constant in the New Field Theory  

Microsoft Academic Search

IN the modification of Maxwell's theory proposed by one of us1, the notion of an `absolute field', called b, played an essential part. In the electrostatic case, the universal constant b is simply the upper limit of the field strength, whilst in the general case of an arbitrary field, b sets a limit to the possible values of when and

Max Born; Erwin Schrödinger

1935-01-01

277

Absolute Time Radiometric Dating: the source of the dates on  

E-print Network

measured with a mass spectrometer. · 2. The decay constant measured by a scintillometer. Basis Time Scale · Radiometric dates from igneous rocks can be used to indirectly date sedimentary rocksAbsolute Time Radiometric Dating: the source of the dates on the Geologic Time Scale Radiometric

Kammer, Thomas

278

Absolute Flux Measurements for IR Spectromicroscopy Michael C. Martina  

E-print Network

. of Chemistry, University of California, Berkeley, CA 94720 1. INTRODUCTION Measurements of the effects a self consistent picture which can be used to estimate the absolute exposure to cells and bacteria which was measured with a disappearing filament style optical pyrometer to have a brightness temperature of ~1343K

279

Measurement of Absolute Vehicle Speed With a Simplified Inverse Model  

Microsoft Academic Search

This paper presents the study of a sensing technique for the measurement of the absolute speed of railway vehicles, which is achieved by detecting the time shift of the track random excitations between two wheelsets of a bogie (or truck). A simplified inverse model is designed to extract particular features of motion at the wheelsets from two inertial sensors mounted

T. X. Mei; H. Li

2010-01-01

280

Absolute phasing of segmented mirrors using the polarization phase sensor  

Microsoft Academic Search

The polarization phase sensor (PPS) is an optical sensor capable of measuring absolute displacements between two segments of a spherical mirror. The sensing apparatus consists of a white-light polarization interferometer which forms a set of interference fringes representative of the displacement between the two segments. A detector array senses these fringes and computer software performs an analysis. The result of

Herbert W. Klumpe III; Barbara A. Lajza-Rooks; James D. Blum

1992-01-01

281

Diurnal Cycles of High Absolute Humidity at the Earth's Surface.  

National Technical Information Service (NTIS)

Previous studies of high humidities at the earth's surface are reviewed as an introduction for the purpose of formulating recommendations for absolute humidity extremes for MIL-STD-210B. Four typical diurnal cycles of dew point and temperature for periods...

D. D. Grantham, H. A. Salmela

1972-01-01

282

FILL'S ALGORITHM FOR ABSOLUTELY CONTINUOUS STOCHASTICALLY MONOTONE KERNELS  

Microsoft Academic Search

Fill, Machida, Murdoch, and Rosenthal (2000) presented their algorithm and its variants to extend the perfect sampling algorithm of Fill (1998) to chains on continuous state spaces. We consider their algorithm for absolutely continuous stochastically monotone kernels, and show the correctness of the algorithm under a set of certain regularity conditions. These conditions succeed in relaxing the previously known hypotheses

MOTOYA MACHIDA

2002-01-01

283

The Orbital and Absolute Magnitude Distributions of Main Belt Asteroids  

E-print Network

We have developed a model-independent analytical method for debiasing the four-dimensional (a,e,i,H) distribution obtained in any asteroid observation program and have applied the technique to results obtained with the 0.9m Spacewatch Telescope. From 1992 to 1995 Spacewatch observed ~3740 deg^2 near the ecliptic and made observations of more than 60,000 asteroids to a limiting magnitude of V~21. The debiased semi-major axis and inclination distributions of Main Belt asteroids in this sample with 11.5asteroids with H asteroids is complete to about absolute magnitudes 12.75, 12.25 and 11.25 in the inner, middle and outer regions of the belt respectively. The number distribution as a function of absolute magnitude cannot be represented by a single power-law (10^{alpha H}) in any region. We were able to define broad ranges in H in each part of the belt where alpha was nearly constant. Within these ranges of H the slope does not correspond to the value of 0.5 expected for an equilibrium cascade in self-similar collisions (Dohnanyi, 1971). The value of alpha varies with absolute magnitude and shows a `kink' in all regions of the belt for H~13. This absolute magnitude corresponds to a diameter ranging from about 8.5 to 12.5 km depending on the albedo or region of the belt.

R. Jedicke; T. S. Metcalfe

1998-01-05

284

Europe's Other Poverty Measures: Absolute Thresholds Underlying Social Assistance  

ERIC Educational Resources Information Center

The first thing many learn about international poverty measurement is that European nations apply a "relative" poverty threshold and that they also do a better job of reducing poverty. Unlike the European model, the "absolute" U.S. poverty threshold does not increase in real value when the nation's standard of living rises, even though it is…

Bavier, Richard

2009-01-01

285

Absolute calibration of Landsat instruments using the moon.  

USGS Publications Warehouse

A lunar observation by Landsat could provide improved radiometric and geometric calibration of both the Thematic Mapper and the Multispectral Scanner in terms of absolute radiometry, determination of the modulation transfer function, and sensitivity to scattered light. A pitch of the spacecraft would be required. -Authors

Kieffer, H.H.; Wildey, R.L.

1985-01-01

286

Combining relative and absolute gravity measurements to enhance volcano monitoring  

NASA Astrophysics Data System (ADS)

To achieve a balance between uncertainty and efficiency in gravity measurements, we have investigated the applicability of combined measurements of absolute and relative gravity as a hybrid method for volcano monitoring. Between 2007 and 2009, three hybrid gravity surveys were conducted at Mt Etna volcano, in June 2007, July 2008, and July 2009. Absolute gravity data were collected with two absolute gravimeters, which represent the state of the art in recent advances in ballistic gravimeter technology: (1) the commercial instrument FG5#238 and (2) the prototype instrument IMGC-02. We carried out several field surveys and confirmed that both the absolute gravimeters can still achieve a 10 ?Gal or better uncertainty even when they are operated in severe environmental conditions. The use of absolute gravimeters in a field survey of the summit area of Mt Etna is unprecedented. The annual changes of the gravity measured over 2007-2008 and 2008-2009 provide unequivocal evidence that during the 2007-2009 period, two main phenomena of subsurface mass redistribution occurred in distinct sectors of the volcano, accompanying different eruptive episodes. From 2007 to 2008, a gravity change of -60 ?Gal was concentrated around the North-East Rift. This coincided with a zone affected by strong extensional tectonics, and hence might have been related to the opening of new voids. Between 2008 and 2009, a North-South elongate feature with a maximum gravity change of +80 ?Gal was identified in the summit craters area. This is interpreted to indicate recharge of a deep-intermediate magma storage zone, which could have occurred when the 2008-2009 eruption was still ongoing.

Greco, F.; Currenti, G.; D'Agostino, G.; Germak, A.; Napoli, R.; Pistorio, A.; Del Negro, C.

2012-09-01

287

The absolute infrared magnitudes of type Ia supernovae  

E-print Network

The absolute luminosities and homogeneity of early-time infrared (IR) light curves of type Ia supernovae are examined. Eight supernovae are considered. These are selected to have accurately known epochs of maximum blue light as well as having reliable distance estimates and/or good light curve coverage. Two approaches to extinction correction are considered. Owing to the low extinction in the IR, the differences in the corrections via the two methods are small. Absolute magnitude light curves in the J, H and K-bands are derived. Six of the events, including five established ``Branch-normal'' supernovae show similar coeval magnitudes. Two of these, SNe 1989B and 1998bu, were observed near maximum infrared light. This occurs about 5 days {\\it before} maximum blue light. Absolute peak magnitudes of about -19.0, -18.7 and -18.8 in J, H & K respectively were obtained. The two spectroscopically peculiar supernovae in the sample, SNe 1986G and 1991T, also show atypical IR behaviour. The light curves of the six similar supernovae can be represented fairly consistently with a single light curve in each of the three bands. In all three IR bands the dispersion in absolute magnitude is about 0.15 mag, and this can be accounted for within the uncertainties of the individual light curves. No significant variation of absolute IR magnitude with B-band light curve decline rate, Delta m_{15}(B), is seen over the range 0.87supernovae should eventually provide cosmological distance estimates which are of equal or even superior quality to those obtained in optical studies.

W. P. S. Meikle

1999-12-07

288

Absolute gravity and GPS measurements in Chile : preliminary results  

NASA Astrophysics Data System (ADS)

High precision gravity combined with GPS geodesy offers increasing potentialities for the study of time variations of the earth gravity field and crustal deformations related with geodynamic, tectonic or volcanic processes. The continental margin of Chile, resulting from the subduction of Nazca and Antarctic plates under the South American plate, belongs to the most active zones in the world where such processes can be observed. During summer 2002, we carried out a first experience of simultaneous absolute gravity and GPS measurements in north and central Chile with the aim to set up a repetition network of precise reference stations. The objectives are : (i) to attempt an estimation of the present-day vertical crustal motions along the andean margin ; (ii) to better constraints the vertical displacements associated with large earthquakes ; (iii) to establish precise calibration lines for relative gravity meters. The measurements have been performed with the FG5 absolute gravity meter (n°206). The sites were selected to ensure precise and safe data acquisition and mid to long-term stability of the stations. Special care was attempted to get measurements on existing sites where other geodetic/gravity observations are available (permanent GPS, DORIS, VLBI, SLR absolute or superconducting gravity). For other sites, differential GPS observations have been realized simultaneously with the gravity measurements. Scintrex CG-3M relative gravity measurements have been taken for earth-tide recording and vertical gravity gradient determinations. A total number of 11 absolute gravity stations have been established in north and central/south Chile. A preliminary processing, confirms that an accuracy of 1 to 3 µGal is achieved for these absolute gravity networks. We present here the first results of this survey and discuss their implications for future monitoring of gravity changes along the south-american plate boundary.

Bonvalot, S.; Comte, D.; Dorbath, L.; Hinderer, J.; Gabalda, G.; Luck, B.; Ruegg, J. C.

2003-04-01

289

A simplified model for thermal-wave cavity self-consistent measurement of thermal diffusivity  

NASA Astrophysics Data System (ADS)

A simplified theoretical model was developed for the thermal-wave cavity (TWC) technique in this study. This model takes thermal radiation into account and can be employed for absolute measurements of the thermal diffusivity of gas and liquid samples without any knowledge of geometrical and thermal parameters of the components of the TWC. Using this model and cavity-length scans, thermal diffusivities of air and distilled water were accurately and precisely measured as (2.191 ± 0.004) × 10-5 and (1.427 ± 0.009) × 10-7 m2 s-1, respectively, in very good agreement with accepted literature values.

Shen, Jun; Zhou, Jianqin; Gu, Caikang; Neill, Stuart; Michaelian, Kirk H.; Fairbridge, Craig; Astrath, Nelson G. C.; Baesso, Mauro L.

2013-12-01

290

A simplified model for thermal-wave cavity self-consistent measurement of thermal diffusivity  

SciTech Connect

A simplified theoretical model was developed for the thermal-wave cavity (TWC) technique in this study. This model takes thermal radiation into account and can be employed for absolute measurements of the thermal diffusivity of gas and liquid samples without any knowledge of geometrical and thermal parameters of the components of the TWC. Using this model and cavity-length scans, thermal diffusivities of air and distilled water were accurately and precisely measured as (2.191 ± 0.004) × 10{sup ?5} and (1.427 ± 0.009) × 10{sup ?7} m{sup 2}?s{sup ?1}, respectively, in very good agreement with accepted literature values.

Shen, Jun, E-mail: jun.shen@nrc-cnrc.gc.ca; Zhou, Jianqin; Gu, Caikang [Energy, Mining and Environment Portfolio, National Research Council Canada, 4250 East Mall, Vancouver, British Columbia V6T 1W5 (Canada)] [Energy, Mining and Environment Portfolio, National Research Council Canada, 4250 East Mall, Vancouver, British Columbia V6T 1W5 (Canada); Neill, Stuart [Energy, Mining and Environment Portfolio, National Research Council Canada, 1200 Montreal Road, Building M-9, Ottawa, Ontario K1A 0R6 (Canada)] [Energy, Mining and Environment Portfolio, National Research Council Canada, 1200 Montreal Road, Building M-9, Ottawa, Ontario K1A 0R6 (Canada); Michaelian, Kirk H.; Fairbridge, Craig [CanmetENERGY, Natural Resources Canada, One Oil Drive Patch, Devon, Alberta T9G 1A8 (Canada)] [CanmetENERGY, Natural Resources Canada, One Oil Drive Patch, Devon, Alberta T9G 1A8 (Canada); Astrath, Nelson G. C.; Baesso, Mauro L. [Departamento de Física, Universidade Estadual de Maringá, Av. Colombo 5790, Maringá, Paraná 87020-900 (Brazil)] [Departamento de Física, Universidade Estadual de Maringá, Av. Colombo 5790, Maringá, Paraná 87020-900 (Brazil)

2013-12-15

291

A new Ultra Precision Interferometer for absolute length measurements down to cryogenic temperatures  

NASA Astrophysics Data System (ADS)

A new Ultra Precision Interferometer (UPI) was built at Physikalisch-Technische Bundesanstalt. As its precursor, the precision interferometer, it was designed for highly precise absolute length measurements of prismatic bodies, e.g. gauge blocks, under well-defined temperature conditions and pressure, making use of phase stepping imaging interferometry. The UPI enables a number of enhanced features, e.g. it is designed for a much better lateral resolution and better temperature stability. In addition to the original concept, the UPI is equipped with an external measurement pathway (EMP) in which a prismatic body can be placed alternatively. The temperature of the EMP can be controlled in a much wider range compared to the temperature of the interferometer's main chamber. An appropriate cryostat system, a precision temperature measurement system and improved imaging interferometry were established to permit absolute length measurements down to cryogenic temperature, demonstrated for the first time ever. Results of such measurements are important for studying thermal expansion of materials from room temperature towards less than 10 K.

Schödel, R.; Walkov, A.; Zenker, M.; Bartl, G.; Meeß, R.; Hagedorn, D.; Gaiser, C.; Thummes, G.; Heltzel, S.

2012-09-01

292

Absolute measurements of the uranium concentration in thick samples using fission-track detectors  

NASA Astrophysics Data System (ADS)

We propose an improved equation for calculating the uranium concentration in thick samples based on induced fission-track counts in an external detector that takes into consideration (1) the fission-fragment ranges in the sample and external detector, (2) the etchable track length and (3) the track counting efficiency in the external detector. The values of these parameters have been determined by calculation and experiment and are shown to have a significant effect on the calculated uranium concentrations. The new equation was tested by calculating the uranium concentrations in standard uranium glasses (CN-5; IRMM-540R) and apatite samples (Durango; horse tooth) in which the uranium content was also determined with independent methods (INAA; ENAA; TIMS). The results show that: (1) accurate measurements with the fission-track method are feasible within a broad range of uranium concentrations and (2) uranium determinations based on standards are only accurate if the standard and sample are made of the same material. Because the absolute fission-tack dating method is also based on accurate thermal neutron fluence measurements and similar correction factors for the track registration and counting efficiencies, this study provides a strong endorsement for the fact that absolute fission-track ages are accurate.

Enkelmann, Eva; Jonckheere, Raymond; Ratschbacher, Lothar

2005-04-01

293

The Centaur 10199 Chariklo: investigation into rotational period, absolute magnitude, and cometary activity  

NASA Astrophysics Data System (ADS)

Context. Rings have recently been discovered around the Centaur 10199 Chariklo. Aims: In this paper we present new photometric data, obtained at the 4.2 m SOAR Telescope, aiming to investigate Chariklo's absolute magnitude and rotational period, which is still unknown, and to look for potential cometary activity. Methods: The field background of the images was very crowded so several approaches were used for the extraction of Chariklo fluxes. The background sources were subtracted using difference image analysis and then aperture photometry was applied. A Fourier polynomial fit was used to determine the period. Results: We find a synodic rotation period of 7.004±0.036 h. The visual absolute magnitude derived from the SOAR data is Hv = 7.03 ± 0.10. We model the rings' contribution to the flux, and find that the derived Hv is consistent with the predicted ring system aspect angle. We also revised the Chariklo system albedo (4.2%) and effective radius (119 ± 5 km) from a re-analysis of Herschel and WISE thermal data obtained during 2010 with the correct Hv value. No coma is detected from the SOAR data, nor in previous VLT images acquired in 2007-2008, where the rings' aspect angle was close to zero. The upper limit to the dust production rate is 2.5 kg/s. Figure 3 is available in electronic form at http://www.aanda.org

Fornasier, S.; Lazzaro, D.; Alvarez-Candal, A.; Snodgrass, C.; Tozzi, G. P.; Carvano, J. M.; Jiménez-Teja, Y.; Silva, J. S.; Bramich, D. M.

2014-08-01

294

Establishing ion ratio thresholds based on absolute peak area for absolute protein quantification using protein cleavage isotope dilution mass spectrometry.  

PubMed

Quantitative mass spectrometry has become central to the field of proteomics and metabolomics. Selected reaction monitoring is a widely used method for the absolute quantification of proteins and metabolites. This method renders high specificity using several product ions measured simultaneously. With growing interest in quantification of molecular species in complex biological samples, confident identification and quantitation has been of particular concern. A method to confirm purity or contamination of product ion spectra has become necessary for achieving accurate and precise quantification. Ion abundance ratio assessments were introduced to alleviate some of these issues. Ion abundance ratios are based on the consistent relative abundance (RA) of specific product ions with respect to the total abundance of all product ions. To date, no standardized method of implementing ion abundance ratios has been established. Thresholds by which product ion contamination is confirmed vary widely and are often arbitrary. This study sought to establish criteria by which the relative abundance of product ions can be evaluated in an absolute quantification experiment. These findings suggest that evaluation of the absolute ion abundance for any given transition is necessary in order to effectively implement RA thresholds. Overall, the variation of the RA value was observed to be relatively constant beyond an absolute threshold ion abundance. Finally, these RA values were observed to fluctuate significantly over a 3 year period, suggesting that these values should be assessed as close as possible to the time at which data is collected for quantification. PMID:25154770

Loziuk, Philip L; Sederoff, Ronald R; Chiang, Vincent L; Muddiman, David C

2014-09-29

295

Handheld Reflective Foil Emissometer with 0.007 Absolute Accuracy at 0.05  

NASA Astrophysics Data System (ADS)

The development and performance of a handheld emissometer for the measurement of the emissivity of highly reflective metallic foils used for the insulation of domestic and commercial buildings are described. Reflective roofing insulation based on a thin coating of metal on a more robust substrate is very widely used in hotter climates to reduce the radiant heat transfer between the ceiling and roof in commercial and residential buildings. The required normal emissivity of these foils is generally below 0.05, so stray reflected ambient infrared radiation (IR) makes traditional reflectance-based measurements of emissivity very difficult to achieve with the required accuracy. Many manufacturers apply additional coatings onto the metallic foil to reduce visible glare during installation on a roof, and to provide protection to the thin reflective layer; however, this layer can also substantially increase the IR emissivity. The system as developed at the National Measurement Institute, Australia (NMIA) is based on the principle of measurement of the modulation in thermal infrared radiation, as the sample is thermally modulated by hot and cold air streams. A commercial infrared to band radiation thermometer with a highly specialized stray and reflected radiation shroud attachment is used as the detector system, allowing for convenient handheld field measurements. The performance and accuracy of the system have been compared with NMIA's reference emissometer systems for a number of typical material samples, demonstrating its capability to measure the absolute thermal emissivity of these very highly reflective foils with an uncertainty of better than.

van der Ham, E. W. M.; Ballico, M. J.

2014-07-01

296

Safety of high speed guided ground transportation systems: An overview of biological effects and mechanisms relevant to EMF exposures from mass transit and electric rail systems. Final report, October 1991-July 1993  

SciTech Connect

The U.S. has implemented a national initiative to develop maglev (magnetic levitation) and other high-speed rail (HSR) systems. There are concerns for potential adverse health effects of the Extremely Low Frequency (3-3,000 Hz) electric and magnetic fields (EMF) produced by these systems. The Environmental Protection Agency's Office of Radiation Programs is assisting the Federal Railroad Administration address these concerns; this comprehensive review is part of that effort. It outlines magnetic field exposure measurements of the TR07 German maglev system compared with other HSR and conventional systems.

Goldberg, R.B.; Creasey, W.A.; Foster, K.R.

1993-08-01

297

EMFs: cutting through the controversy.  

PubMed Central

SOME SCIENTISTS ALLEGE that exposure to electric and magnetic fields generated by electric power delivery systems is responsible for certain cancers (particularly among children), reproductive dysfunction, birth defects, neurological disorders, and Alzheimer's disease. Some activist groups believe the hazard to be so great that they are calling for closure of schools and other public facilities near power lines and restructuring of the entire electric power delivery system. Some utilities, with equally strong beliefs, claim that there is no proof of risk. They argue that the science is sufficient to confirm the alleged associations and that no action is warranted. This article provides a broad overview of the current scientific data on the association between magnetic fields and disease, providing summary risk estimates and highlighting the uncertainties in the data. Building on this information, three complementary policy perspectives are presented. From a fiscally conservative perspective, the cost of mitigation already instituted far exceeds the health protection offered and mitigation of other environmental risks is more important. From a cost-benefit view, only limited, low-cost mitigation should be considered. These measures, however, would substantially reduce many exposures. From an aggressive exposure reduction perspective, much can be done to reduce exposure by personal and societal actions. If the suggested association is validated, substantially reducing magnetic field exposure could lower health risks. Images p205-a p207-a PMID:8643811

Wartenberg, D

1996-01-01

298

Absolute wind measurements in the lower thermosphere of Venus using infrared heterodyne spectroscopy  

NASA Technical Reports Server (NTRS)

The first absolute wind velocities above the Venusian cloud-tops were obtained using NASA/Goddard infrared heterodyne spectrometers at the NASA Infrared Telescope Facility (IRTF) and the McMath Solar Telescope. Beam-integrated Doppler displacements in the non-thermal emission core of (12)C(16)O2 10.33 micron R(8) sampled the line of sight projection of the lower thermospheric wind field (100 to 120 km). A field-usable Lamb-dip laser stabilization system, developed for spectrometer absolute frequency calibration to less than + or - 0.1 MHz, allowed S/N-limited line of sight velocity resolution at the 1 m/s level. The spectrometer's diffraction-limited beam (1.7 arc-second HPBW at McMath, 0.9 arc-second HPBW at IRTF), and 1 to 2 arc-second seeing, provided the spatial resolution necessary for circulation model discrimination. Qualitative analysis of beam-integrated winds provided definitive evidence of a dominant subsolar-antisolar circulation in the lower thermosphere. Beam-integrated winds were modelled with a 100x100 grid over the beam, incorporating beam spatial rolloff and across-the-beam gradients in non-thermal emission intensity, line of sight projection geometry, and horizontal wind velocity. Horizontal wind velocity was derived from a 2-parameter model wind field comprised of subsolar-antisolar and zonal components. Best-fit models indicated a dominant subsolar-antisolar flow with 120 m/s cross-terminator winds and a retrograde zonal component with a 25 m/s equatorial velocity. A review of all dynamical indicators above the cloud-tops allowed development of an integrated and self-consistent picture of circulation in the 70 to 200 km range.

Goldstein, Jeffrey J.

1990-01-01

299

Absolute fluence measurement for a prototype neutron radiotherapy source.  

PubMed

An inexpensive recoil-proton counter telescope has been designed for absolute fluence measurements of a gas-target neutron source for radiation therapy. The detector has an absolute efficiency of 1.1 times 10-minus 9 at 20 cm from an isotropic source and is useful for production rates of 10-9 minus 10-13 neutrons per second. The telescope consists of a thin hydrogenous irradiator foil and a surface-barrier detector to count recoil protons within a defined solid angle. The telescope provides n-gamma discrimination as well as discrimination against scattered neutrons. Initial tests of the counter telescope were performed using the DD reaction employed in development stages of the gas target. A clear separation of full-energy recoil protons from background and scattered neutron events was evident in the pulse-height spectra without the use of coincidence gating techniques. PMID:806776

Beach, J L; McCullough, E C

1975-01-01

300

Simultaneously improving the sensitivity and absolute accuracy of CPT magnetometer.  

PubMed

A new method to improve the sensitivity and absolute accuracy simultaneously for coherent population trapping (CPT) magnetometer based on the differential detection method is presented. Two modulated optical beams with orthogonal circular polarizations are applied, in one of which two magnetic resonances are excited simultaneously by modulating a 3.4GHz microwave with Larmor frequency. When a microwave frequency shift is introduced, the difference in the power transmitted through the cell in each beam shows a low noise resonance. The sensitivity of 2pT/Hz @ 10Hz is achieved. Meanwhile, the absolute accuracy of ± 0.5nT within the magnetic field ranging from 20000nT to 100000nT is realized. PMID:24664032

Liang, Shang-Qing; Yang, Guo-Qing; Xu, Yun-Fei; Lin, Qiang; Liu, Zhi-Heng; Chen, Zheng-Xiang

2014-03-24

301

Absolute calibration of TFTR helium proportional counters (abstract)a)  

NASA Astrophysics Data System (ADS)

The TFTR helium proportional counters are located in the central five (5) channels of the TFTR multichannel neutron collimator. These detectors were absolutely calibrated using a 14 MeV neutron generator positioned at the horizontal midplane of the TFTR vacuum vessel. The neutron generator position was scanned in centimeter steps to determine the collimator aperture width to 14 MeV neutrons and the absolute sensitivity of each channel. Neutron profiles were measured for TFTR plasmas with time resolution between 5 and 50 ms depending upon count rates. The He detectors were used to measure the burnup of 1 MeV tritons in deuterium plasmas, the transport of tritium in trace tritium experiments, and the residual tritium levels in plasmas following 50:50 DT experiments.

Strachan, J. D.; Barnes, Cris W.; Diesso, M.; Jassby, D.; Johnson, L.; Loughlin, M.; McCauley, S.; Munsat, T.; Roquemore, A. L.

1995-01-01

302

Absolute charge calibration of scintillating screens for relativistic electron detection  

SciTech Connect

We report on new charge calibrations and linearity tests with high-dynamic range for eight different scintillating screens typically used for the detection of relativistic electrons from laser-plasma based acceleration schemes. The absolute charge calibration was done with picosecond electron bunches at the ELBE linear accelerator in Dresden. The lower detection limit in our setup for the most sensitive scintillating screen (KODAK Biomax MS) was 10 fC/mm{sup 2}. The screens showed a linear photon-to-charge dependency over several orders of magnitude. An onset of saturation effects starting around 10-100 pC/mm{sup 2} was found for some of the screens. Additionally, a constant light source was employed as a luminosity reference to simplify the transfer of a one-time absolute calibration to different experimental setups.

Buck, A.; Popp, A.; Schmid, K.; Karsch, S.; Krausz, F. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching (Germany); Ludwig-Maximilians-Universitaet Muenchen, Am Coulombwall 1, D-85748 Garching (Germany); Zeil, K.; Jochmann, A.; Kraft, S. D.; Sauerbrey, R.; Cowan, T.; Schramm, U. [Forschungszentrum Dresden Rossendorf, Bautzner Landstrasse 400, D-01328 Dresden (Germany); Hidding, B.; Kudyakov, T. [Institut fuer Laser und Plasmaphysik, Heinrich-Heine-Universitaet Duesseldorf, Universitaetsstrasse 1, D-40225 Duesseldorf (Germany); Sears, C. M. S.; Veisz, L. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Strasse 1, D-85748 Garching (Germany); Pawelke, J. [Forschungszentrum Dresden Rossendorf, Bautzner Landstrasse 400, D-01328 Dresden (Germany); Oncoray, Technische Universitaet Dresden, Fetscher Strasse 74, D-01307 Dresden (Germany)

2010-03-15

303

Absolute timing with the SWIFT X-ray telescope (XRT)  

NASA Astrophysics Data System (ADS)

The X-ray telescope (XRT) on board Swift, launched on 2004 Nov 20, is performing astrometric, spectroscopic and photometric observations of the X-ray emission from Gamma-ray burst afterglows in the energy band 0.2-10 keV. In this paper, we describe the results of the in-flight calibration relative to the XRT timing resolution and absolute timing capabilities. The timing calibration has been performed comparing the main pulse phases of the Crab profile obtained from several XRT observations in Low Rate Photodiode and Windowed Timing mode with those from contemporaneous RXTE observations. The XRT absolute timing is well reproduced with an accuracy of 200 ?s for the Low Rate Photodiode and 300 ?s for the Windowed Timing mode.

Cusumano, G.; Mangano, V.; Mineo, T.; La Parola, V.; La Barbera, A.; Campana, S.; Chincarini, G.; Tagliaferri, G.; Moretti, A.; Romano, P.; Capalbi, M.; Perri, M.; Giommi, P.; Burrows, D.; Morris, D.; Hill, J. E.; Kennea, J.; Nousek, J. A.; Pagani, C.; Angelini, L.; Osborne, J. P.; Abbey, A. F.; Beardmore, A.; Goad, M. R.; Page, K.; Wells, A.

2005-08-01

304

Absolute magnitude calibration using trigonometric parallax - Incomplete, spectroscopic samples  

NASA Technical Reports Server (NTRS)

A new numerical algorithm is used to calibrate the absolute magnitude of spectroscopically selected stars from their observed trigonometric parallax. This procedure, based on maximum-likelihood estimation, can retrieve unbiased estimates of the intrinsic absolute magnitude and its dispersion even from incomplete samples suffering from selection biases in apparent magnitude and color. It can also make full use of low accuracy and negative parallaxes and incorporate censorship on reported parallax values. Accurate error estimates are derived for each of the fitted parameters. The algorithm allows an a posteriori check of whether the fitted model gives a good representation of the observations. The procedure is described in general and applied to both real and simulated data.

Ratnatunga, Kavan U.; Casertano, Stefano

1991-01-01

305

In Self-contradiction, Machian Geocentrism Entails Absolute Space  

E-print Network

Luka Popov has attempted to advance Machian physics by maintaining that the heliocentric system must be replaced by Tycho Brahe's geocentric system. We show that while geocentrism relies on Mach's contention that accelerations are relative, this contention is untenable because, inter alia, the consequences of an acceleration of an object with respect to the fixed stars cannot be duplicated by acceleration of the stars with respect to this object and, if the universe and a co-rotating observer have the same angular velocity, this motion is detectable because they have different linear velocities. Also, geocentrism precludes the relativity of accelerations and leads to an absolute space while Mach argued against absolute space, Popov's result that the force exerted by the Earth on the Sun depends on the square of the Sun's mass but is independent of the Earth's mass is paradoxical, and the annual asymmetry of the Cosmic Microwave Background falsifies all geocentric or 'Tychonic/Brahean) systems.

Hartman, Herbert I

2014-01-01

306

Electrically calibrated absolute radiometer suitable for measurement automation  

NASA Astrophysics Data System (ADS)

New electrically calibrated absolute radiometers (ESRs) were developed having fast response and high responsivity; these ESRs are specially useful for measurement automation. They are fabricated using thin film techniques and have a responsivity of approximately 0.3 V/W, a time constant between 2.5 and 3.0 s and a noise equivalent power of around 20 nW. Only a correction for the goldblack absorber reflectance is required, and the overall accuracy of the radiometers is + or - 0.1 percent. One of the main applications of absolute radiometers is to the accurate spectral calibration of secondary radiometers. The automation of this calibration procedure is discussed for the visible and near-IR spectral region. It is shown that the use of automation in conjunction with the new ESRs greatly simplifies calibrations and reduces turnaround time while allowing calibration accuracies of close to + or 0.1 percent.

Boivin, L.-P.; McNeely, F. T.

1986-02-01

307

First results from Swarm's Absolute Scalar Magnetometers burst mode  

NASA Astrophysics Data System (ADS)

Swarm's Absolute Scalar Magnetometers (ASM) provide absolute scalar measurements of the magnetic field with high accuracy and stability on the three satellites of the mission. These ASMs nominally run at 1 Hz. But they can also run at 250 Hz frequency using a so-called "burst" mode. This possibility is to be taken advantage of during commissioning (on-going, at time of writing this abstract). In particular, the burst mode is to be run simultaneously on all three satellites over several days. Although these burst mode sessions were initially driven by the engineering need to explore the high frequency spectral content of the signal measured by the ASMs, they can also be used to look for meaningful high frequency geomagnetic signal. In this poster, the data acquired (by the time of the meeting) will be presented and their main characteristics discussed.

Hulot, Gauthier; Vigneron, Pierre; Brocco, Laura; Crespo-Grau, Raul; Chulliat, Arnaud; Léger, Jean-Michel; Jager, Thomas; Bertrand, François; Boness, Axel; Fratter, Isabelle

2014-05-01

308

Absolute measurement of the extreme UV solar flux  

NASA Technical Reports Server (NTRS)

A windowless rare-gas ionization chamber has been developed to measure the absolute value of the solar extreme UV flux in the 50-575-A region. Successful results were obtained on a solar-pointing sounding rocket. The ionization chamber, operated in total absorption, is an inherently stable absolute detector of ionizing UV radiation and was designed to be independent of effects from secondary ionization and gas effusion. The net error of the measurement is + or - 7.3 percent, which is primarily due to residual outgassing in the instrument, other errors such as multiple ionization, photoelectron collection, and extrapolation to the zero atmospheric optical depth being small in comparison. For the day of the flight, Aug. 10, 1982, the solar irradiance (50-575 A), normalized to unit solar distance, was found to be 5.71 + or - 0.42 x 10 to the 10th photons per sq cm sec.

Carlson, R. W.; Ogawa, H. S.; Judge, D. L.; Phillips, E.

1984-01-01

309

Absolute bioavailability of letrozole in healthy postmenopausal women.  

PubMed

Letrozole is a new non-steroidal inhibitor of the aromatase enzyme system. It is currently under development for the treatment of postmenopausal women with advanced breast cancer. Absolute bioavailability of letrozole when given orally as one 2.5 mg film-coated tablet in comparison to the same dose given intravenously as a bolus injection was studied in 12 healthy postmenopausal women. Letrozole absolute systemic bioavailability after p.o. administration was 99.9 +/- 16.3%. Elimination of letrozole was slow. Total-body clearance of letrozole from plasma after i.v. administration was low (2.21 L h-1). The calculated distribution volume at steady state (1.87 L kg-1) suggests a rather high tissue distribution. Biotransformation of letrozole is the main elimination mechanism with the glucuronide conjugate of the secondary alcohol metabolite being the predominant species found in urine. The two study treatments were tolerated equally well. PMID:9429742

Sioufi, A; Gauducheau, N; Pineau, V; Marfil, F; Jaouen, A; Cardot, J M; Godbillon, J; Czendlik, C; Howald, H; Pfister, C; Vreeland, F

1997-12-01

310

Stellar Absolute Magnitudes via the Statistical Parallax Method  

E-print Network

I review statistical parallax absolute magnitude determinations which employ data from the HIPPARCOS satellite for RR Lyrae and Cepheid variables, and for several other stellar classes. Five groups have studied the RR Lyrae stars, and the results are reassuringly consistent: M_V(RR) = 0.77 +- 0.13 mag at [Fe/H] = -1.6 dex. Extensive Monte Carlo simulations showed that systematic errors are small (~0.03 mag or less), and corrections for them were applied in the above result. The RR Lyrae result is thus very secure. A statistical parallax study of Cepheids found the Period--Luminosity zero-point to be considerably fainter than studies based on HIPPARCOS trigonometric parallaxes. The distance modulus of the Large Magellanic Cloud derived from this zero-point is in excellent agreement with that derived using the RR Lyrae result. I discuss why the statistical parallax absolute magnitude calibrations differ with some other RR Lyrae and Cepheid calibrations.

Andrew C. Layden

1998-10-28

311

In-flight absolute radiometric calibration of the thematic mapper  

NASA Technical Reports Server (NTRS)

In order to determine temporal changes of the absolute radiometric calibration of the entire TM system in flight spectroradiometric measurements of the ground and the atmosphere were made simultaneously with TM image collections over the White Sands, New Mexico area. By entering the measured values in an atmospheric radiative transfer program, the radiance levels in four of the spectral bands of the TM were determined, band 1:0.45 to 0.52 micrometers, band 2:0.53 to 0.61 micrometers band 3:0.62 to 0.70 micrometers and 4:0.78 to 0.91 micrometers. These levels were compared to the output digital counts from the detectors that sampled the radiometrically measured ground area, thus providing an absolute radiometric calibration of the entire TM system utilizing those detectors.

Castle, K. R.; Holm, R. G.; Kastner, C. J.; Palmer, J. M.; Slater, P. N.; Dinguirard, M.; Ezra, C. E.; Jackson, R. D.; Savage, R. K.

1984-01-01

312

In-flight absolute radiometric calibration of the Thematic Mapper  

NASA Technical Reports Server (NTRS)

In order to determine temporal changes of the absolute radiometric calibration of the entire TM system in flight spectroradiometric measurements of the ground and the atmosphere were made simultaneously with TM image collections over the White Sands, NM area. By entering the measured values in an atmospheric radiative transfer program, the radiance levels in four of the spectral bands of the TM were determined, band 1: 0.45 to 0.52 micrometers, band 2: 0.53 to 0.61 micrometers, band 3: 0.62 to 0.70 micrometers, and 4: 0.78 to 0.91 micrometers. These levels were compared to the output digital counts from the detectors that sampled the radiometrically measured ground area, thus providing an absolute radiometric calibration of the entire TM system utilizing those detectors. Previously announced in STAR as N84-15633

Castle, K. R.; Holm, R. G.; Kastner, C. J.; Palmer, J. M.; Slater, P. N.; Dinguirard, M.; Ezra, C. E.; Jackson, R. D.; Savage, R. K.

1984-01-01

313

A comparison of a quasi-perpendicular method of absolute palaeointensity determination with other thermal and  

E-print Network

10 March 2007 Editor: R.D. van der Hilst Available online 16 March 2007 Abstract We describe, test are subject to the same risks as conventional experiments when performed on samples containing MD grains problems such as constraining geodynamo theory, dating young oceanic crust, and understanding core

Utrecht, Universiteit

314

The measurement of absolute thermal neutron flux using liquid scintillation counting techniques  

E-print Network

section of 0. 109/cm. 1. 1 0. 8 ! 1 i 0 6 8 10 X, Molecule C&HS/ Molecule C7H7C1 FIG. 3 DENSITY OF BENZYL CHLORIDE-TOLUENE SOLUTION 19 CHAPTER IV PROCEDURE Foil Activation The center of the core of the AGN 2D1 Reactor, which was the location... section of 0. 109/cm. 1. 1 0. 8 ! 1 i 0 6 8 10 X, Molecule C&HS/ Molecule C7H7C1 FIG. 3 DENSITY OF BENZYL CHLORIDE-TOLUENE SOLUTION 19 CHAPTER IV PROCEDURE Foil Activation The center of the core of the AGN 2D1 Reactor, which was the location...

Walker, Jack Vernon

2012-06-07

315

Synthesis and absolute configuration of demethyl (C-11) cezomycin.  

PubMed

The synthesis of (-)-demethyl (C-11) cezomycin was achieved through an efficient route that features the use of a Kulinkovich reaction to couple two multifunctionality-containing fragments and a cascade of ring opening of cyclopropanol/1,5-hydrogen shift/desilylation-oxidation. The hidden yet undeniable problem of irreproducible specific rotation for this family of compounds was solved by sufficient acidification. The absolute configuration for the natural product was thus established as the mirror image of the synthetic sample. PMID:23881716

Li, Shao-Gang; Wu, Yikang

2013-11-01

316

The absolute infrared magnitudes of type Ia supernovae  

Microsoft Academic Search

The absolute luminosities and homogeneity of early-time infrared (IR) light\\u000acurves of type Ia supernovae are examined. Eight supernovae are considered.\\u000aThese are selected to have accurately known epochs of maximum blue light as\\u000awell as having reliable distance estimates and\\/or good light curve coverage.\\u000aTwo approaches to extinction correction are considered. Owing to the low\\u000aextinction in the IR,

W. P. S. Meikle

1999-01-01

317

Monocular 3D scene reconstruction at absolute scale  

Microsoft Academic Search

In this article we propose a method for combining geometric and real-aperture methods for monocular three-dimensional (3D) reconstruction of static scenes at absolute scale. Our algorithm relies on a sequence of images of the object acquired by a monocular camera of fixed focal setting from different viewpoints. Object features are tracked over a range of distances from the camera with

Christian Wöhler; Pablo d’Angelo; Lars Krüger; Annika Kuhl; Horst-Michael Groß

2009-01-01

318

Absolute-gravity stations in Western Dronning Maud Land, Antarctica  

NASA Astrophysics Data System (ADS)

Absolute-gravity stations are an important part of the geodetic infrastructure of the Antarctic. They provide accurate starting values for gravity surveys performed e.g. for the determination of the geoid, for geological studies and for geophysical investigations. The time variation in gravity determined from repeated absolute-gravity measurements provides insights into the Glacial Isostatic Adjustment (GIA) and into solid Earth deformation due to variation in contemporary ice load. Given sufficient joint coverage with International Terrestrial Reference Frame (ITRF) sites, gravity rates in high latitudes could in principle provide an independent check of the geocentricity of the z-dot (velocities in the direction of the rotation axis of the Earth) of the ITRF. We review the absolute gravity stations in Western and Central Dronning Maud Land. The oldest station is at the Finnish base Aboa, with 5 measurements by the Finnish Geodetic Institute (FGI) starting with the FINNARP 1993 expedition. Measurements at Maitri (India) and Novolazarevskaya (Russia) were first performed in 2004 by the National Geophysical Research Institute (NGRI) of India, and by the FGI, respectively. In the season 2010/11 a new station was constructed at Troll (Norway). In the season 2011/12 the aforementioned four sites were occupied by the FG5-221 absolute gravimeter of the FGI. At Sanae IV (South Africa) there are previous occupations by the FG5-221, in 2003/4 and 2005/6. All these bases have continuous GNSS stations. Numerous supporting measurements have been made at the sites: microgravity networks, levelling and GNSS ties to excentres etc., for controlling the stability of the stations. At some sites, nearby glacier elevations were surveyed to monitor the attraction of the variable close-field snow and ice masses. We give a description of the sites and the measurements performed at them. The work has benefited from the co-operation in the COST Action ES0701 "Improved Constraints on Models of GIA".

Mäkinen, Jaakko; Rasindra, Ravik; Chand, Uttam; Tiwari, Virendra; Lukin, Valery; Anisimov, Michail; Melvaer, Yngve; Melland, Gudmund; Koivula, Hannu; Näränen, Jyri; Poutanen, Markku

2013-04-01

319

Absolute Source Activity Measurement with a Single Detector  

SciTech Connect

In the present paper the activity of {sup 60}Co source was measured using the full absorption, sum and random coincidences (pile up) peaks and the total spectrum area in the gamma spectra. By the exact treatment of the chance coincidence and pile-up events, surprisingly good results were obtained. With the source on the detector end-cap (when the angular correlation effects are negligible), this simple method yields absolute activity values deviating from the reference activity for about 1 percent.

Bikit, I.; Nemes, T.; Mrdja, D.; Forkapic, S. [Department of Physics, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovica 4, 21 000 Novi Sad (Serbia)

2009-08-26

320

Diagnostic Application of Absolute Neutron Activation Analysis in Hematology  

SciTech Connect

The Absolute Neutron Activation Analysis (ANAA) technique was used to determine element concentrations of Cl and Na in blood of healthy group (male and female blood donators), select from Blood Banks at Sao Paulo city, to provide information which can help in diagnosis of patients. This study permitted to perform a discussion about the advantages and limitations of using this nuclear methodology in hematological examinations.

Zamboni, C.B.; Oliveira, L.C.; Dalaqua, L. Jr.

2004-10-03

321

Secular absolute gravity trends in the northern Cascadia Subduction Zone  

Microsoft Academic Search

High-precision absolute gravity (AG) observations are sensitive to vertical motion of the observation site as well as mass redistribution within (and below) the underlying, slowly-deforming crust. The deformation gravity gradient (DGG) may be defined as the ratio of the time rate of change of surface gravity (g-dot) to vertical crustal velocity (h-dot) and provides insight into the deformation process. On

J. A. Henton; A. Lambert; N. Courtier; S. Mazzotti; H. Dragert

2009-01-01

322

Absolute Gravity Measurements in the Cascadia Subduction Zone  

Microsoft Academic Search

Monitoring of temporal gravity change at GPS sites provides an independent means of verifying inter-seismic crustal deformation associated with a locked subduction zone. High-precision gravity measurements are theoretically sensitive to both the vertical displacement of the observation site and mass redistribution in the underlying, slowly-deforming crust. FG5 absolute gravity observations have been carried out a few times per year over

A. Lambert; N. Courtier; H. Dragert; T. S. James; M. Schmidt; K. Wang; J. He

2001-01-01

323

Purely absolutely continuous spectrum for almost Mathieu operators  

SciTech Connect

Using a recent result of Sinai, the authors prove that the almost Mathieu operators acting on l{sup 2}(Z), (H{sub {alpha}{lambda}}Psi)(n) = {Psi}(n + 1) + {Psi}(n {minus} 1) + {lambda} cos({omega}n + {alpha}) {Psi}(n), have a purely absolutely continuous spectrum for almost all {alpha} provided that {omega} is a good irrational and {lambda} is sufficiently small. Furthermore, the generalized eigenfunctions are quasiperiodic.

Chulaevsky, V.; Delyon, F. (Research Computing Center, Pushchino (USSR))

1989-06-01

324

Absolute intensity of radiation emitted by uranium plasmas  

NASA Technical Reports Server (NTRS)

The absolute intensity of radiation emitted by fissioning and nonfissioning uranium plasmas in the spectral range from 350 nm to 1000 nm was measured. The plasma was produced in a plasma-focus apparatus and the plasma properties are simular to those anticipated for plasma-core nuclear reactors. The results are expected to contribute to the establishment of design criteria for the development of plasma-core reactors.

Jalufka, N. W.; Lee, J. H.; Mcfarland, D. R.

1975-01-01

325

Ecoefficiency analysis of consumer durables using absolute shadow prices  

Microsoft Academic Search

We develop a method for eco-efficiency analysis of consumer durables that is based on Data Envelopment Analysis (DEA). In\\u000a contrast to previous product efficiency studies, we consider the measurement problem from the policy perspective. The innovation\\u000a of the paper is to measure efficiency in terms of absolute shadow prices that are optimized endogenously within the model\\u000a to maximize efficiency of

Mika Kortelainen; Timo Kuosmanen

2007-01-01

326

THE ABSOLUTE MAGNITUDES OF TYPE Ia SUPERNOVAE IN THE ULTRAVIOLET  

SciTech Connect

We examine the absolute magnitudes and light-curve shapes of 14 nearby (redshift z = 0.004-0.027) Type Ia supernovae (SNe Ia) observed in the ultraviolet (UV) with the Swift Ultraviolet/Optical Telescope. Colors and absolute magnitudes are calculated using both a standard Milky Way extinction law and one for the Large Magellanic Cloud that has been modified by circumstellar scattering. We find very different behavior in the near-UV filters (uvw1{sub rc} covering {approx}2600-3300 A after removing optical light, and u {approx} 3000-4000 A) compared to a mid-UV filter (uvm2 {approx}2000-2400 A). The uvw1{sub rc} - b colors show a scatter of {approx}0.3 mag while uvm2-b scatters by nearly 0.9 mag. Similarly, while the scatter in colors between neighboring filters is small in the optical and somewhat larger in the near-UV, the large scatter in the uvm2 - uvw1 colors implies significantly larger spectral variability below 2600 A. We find that in the near-UV the absolute magnitudes at peak brightness of normal SNe Ia in our sample are correlated with the optical decay rate with a scatter of 0.4 mag, comparable to that found for the optical in our sample. However, in the mid-UV the scatter is larger, {approx}1 mag, possibly indicating differences in metallicity. We find no strong correlation between either the UV light-curve shapes or the UV colors and the UV absolute magnitudes. With larger samples, the UV luminosity might be useful as an additional constraint to help determine distance, extinction, and metallicity in order to improve the utility of SNe Ia as standardized candles.

Brown, Peter J.; Roming, Peter W. A.; Ciardullo, Robin; Gronwall, Caryl; Hoversten, Erik A.; Pritchard, Tyler [Department of Astronomy and Astrophysics, Pennsylvania State University, University Park, PA 16802 (United States); Milne, Peter [Steward Observatory, University of Arizona, Tucson, AZ 85719 (United States); Bufano, Filomena; Mazzali, Paolo [INAF-Osservatorio Astronomico di Padova, Vicolo dell'Osservatorio 5, I-35122 Padova (Italy); Elias-Rosa, Nancy [Spitzer Science Center, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Filippenko, Alexei V.; Li Weidong [Department of Astronomy, University of California, Berkeley, CA 94720-3411 (United States); Foley, Ryan J.; Hicken, Malcolm; Kirshner, Robert P. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Gehrels, Neil; Holland, Stephen T.; Immler, Stefan [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Phillips, Mark M. [Las Campanas Observatory, Casilla 601, La Serena (Chile); Still, Martin, E-mail: pbrown@physics.utah.ed [Mullard Space Science Laboratory, Department of Space and Climate Physics, University College London, Holmbury St. Mary, Dorking, Surrey, RH5 6NT (United Kingdom)

2010-10-01

327

New Ultra-High Sensitivity, Absolute, Linear, and Rotary Encoders  

NASA Technical Reports Server (NTRS)

Several new types of absolute optical encoders of both rotary and linear function are discussed. The means for encoding are complete departures from conventional optical encoders and offer advantages of compact form, immunity to damage-induced dropouts of position information, and about an order of magnitude higher sensitivity over what is commercially available. Rotary versions have sensitivity from 0.02 arcseconds down to 0.003 arcsecond while linear models have sensitivity of 10 nm.

Leviton, Douglas B.

1998-01-01

328

Design considerations and validation of the MSTAR absolute metrology system  

Microsoft Academic Search

Absolute metrology measures the actual distance between two optical fiducials. A number of methods have been employed, including pulsed time-of-flight, intensity-modulated optical beam, and two-color interferometry. The rms accuracy is currently limited to ~5 microns. Resolving the integer number of wavelengths requires a 1-sigma range accuracy of ~0.1 microns. Closing this gap has a large pay-off: the range (length measurement)

Robert D. Peters; Oliver P. Lay; Serge Dubovitsky; Johan Burger; Muthu Jeganathan

2004-01-01

329

Absolute calibration of polymer gel dosimeters using scintillating fibers  

NASA Astrophysics Data System (ADS)

Accurate dose distributions are still difficult to obtain using polymer gel dosimetry. While the causes for observed discrepancies are being tracked and understood in details, solutions remain elusive. Causes for discrepancies in absolute dose distributions obtained by polymer gel dosimetry include imaging artefacts and errors associated with the calibration procedure. In this preliminary study, we wanted to verify whether scintillation fiber detectors could be used to improve the accuracy of dose distributions determined by polymer gel dosimeters.

Archambault, Louis; Leclerc, Ghyslain; Beaulieu, Luc; Lepage, Martin

2006-12-01

330

Assignment of Absolute Configuration to SCH 351448 via Total Synthesis?  

PubMed Central

The synthesis and absolute configuration of SCH 351448, an interesting ionophoric natural product, are reported herein. Mukaiyama aldol-Prins and segment-coupling Prins reactions were employed to construct the constituent tetrahydropyrans of SCH 351448. Efforts to assemble the C2-symmetric core of the natural product by a templated olefin metathesis strategy are described, however, a stepwise fragment assembly was ultimately utilized to complete the target molecule. PMID:18543942

Cheung, Lael L.; Marumoto, Shinji; Anderson, Christopher D.

2008-01-01

331

Son preference in Indian families: absolute versus relative wealth effects.  

PubMed

The desire for male children is prevalent in India, where son preference has been shown to affect fertility behavior and intrahousehold allocation of resources. Economic theory predicts less gender discrimination in wealthier households, but demographers and sociologists have argued that wealth can exacerbate bias in the Indian context. I argue that these apparently conflicting theories can be reconciled and simultaneously tested if one considers that they are based on two different notions of wealth: one related to resource constraints (absolute wealth), and the other to notions of local status (relative wealth). Using cross-sectional data from the 1998-1999 and 2005-2006 National Family and Health Surveys, I construct measures of absolute and relative wealth by using principal components analysis. A series of statistical models of son preference is estimated by using multilevel methods. Results consistently show that higher absolute wealth is strongly associated with lower son preference, and the effect is 20%-40% stronger when the household's community-specific wealth score is included in the regression. Coefficients on relative wealth are positive and significant although lower in magnitude. Results are robust to using different samples, alternative groupings of households in local areas, different estimation methods, and alternative dependent variables. PMID:21302027

Gaudin, Sylvestre

2011-02-01

332

Absolute cross sections for electron scattering from furan  

NASA Astrophysics Data System (ADS)

We report results of measurements and calculations of absolute cross sections for electron scattering from furan molecules (C4H4O). The experimental absolute differential cross sections (DCSs) for elastic electron scattering were obtained for the incident energies from 50 eV to 300 eV and for scattering angles from 20º to 110º, by using a crossed electron-target beam setup and the relative flow technique for calibration to the absolute scale. The calculations of the electron interaction cross sections are based on a corrected form of the independent-atom method, known as the screening corrected additivity rule (SCAR) procedure and using an improved quasifree absorption model. The latter calculations also account for rotational excitations in the approximation of a free electric dipole and were used to obtain elastic DCSs as well as total and integral elastic cross sections which are tabulated in the energy range from 10 to 10 000 eV. All SCAR calculated cross sections agree very well with both the present and previously published experimental results. Additionally, calculations based on the first Born approximation were performed to calculate both elastic and vibrationally inelastic DCSs for all the modes of furane, in the energy range from 50 eV to 300 eV. The ratios of the summed vibrational to elastic DCSs are presented and discussed. Finally, the present results for furan are compared with previously published elastic DCSs for the tetrahydrofuran molecule and discussed.

Maljkovi?, J. B.; Blanco, F.; ?urík, R.; García, G.; Marinkovi?, B. P.; Milosavljevi?, A. R.

2012-08-01

333

Peripheral absolute threshold spectral sensitivity in retinitis pigmentosa.  

PubMed Central

Dark-adapted spectral sensitivities were measured in the peripheral retinas of 38 patients diagnosed as having typical retinitis pigmentosa (RP) and in 3 normal volunteers. The patients included those having autosomal dominant and autosomal recessive inheritance patterns. Results were analysed by comparisons with the CIE standard scotopic spectral visibility function and with Judd's modification of the photopic spectral visibility function, with consideration of contributions from changes in spectral transmission of preretinal media. The data show 3 general patterns. One group of patients had absolute threshold spectral sensitivities that were fit by Judd's photopic visibility curve. Absolute threshold spectral sensitivities for a second group of patients were fit by a normal scotopic spectral visibility curve. The third group of patients had absolute threshold spectral sensitivities that were fit by a combination of scotopic and photopic spectral visibility curves. The autosomal dominant and autosomal recessive modes of inheritance were represented in each group of patients. These data indicate that RP patients have normal rod and/or cone spectral sensitivities, and support the subclassification of patients described previously by Massof and Finkelstein. PMID:7459312

Massof, R W; Johnson, M A; Finkelstein, D

1981-01-01

334

Jasminum sambac flower absolutes from India and China--geographic variations.  

PubMed

Seven Jasminum sambac flower absolutes from different locations in the southern Indian state of Tamil Nadu were analyzed using GC and GC-MS. Focus was placed on 41 key ingredients to investigate geographic variations in this species. These seven absolutes were compared with an Indian bud absolute and commercially available J. sambac flower absolutes from India and China. All absolutes showed broad variations for the 10 main ingredients between 8% and 96%. In addition, the odor of Indian and Chinese J. sambac flower absolutes were assessed. PMID:22799098

Braun, Norbert A; Sim, Sherina

2012-05-01

335

Absolute evaluation of out-of-band radiation from laser-produced tin plasmas for extreme ultraviolet lithography  

SciTech Connect

Out-of-band (OOB) radiation (at wavelengths longer than 130 nm) from an extreme ultraviolet (EUV) light source reduces the precision of lithography. The energy of the OOB radiation from laser-produced Sn plasmas were measured by using an absolutely calibrated transmission grating spectrometer equipped with a charge-coupled device. The dependence of the OOB radiant energy on the mass and size of the tin fuel was clarified. The dominant source of the OOB radiation is peripheral heating around the laser spot via electron thermal conduction and radiation from the high-temperature EUV emission region.

Sakaguchi, Hirokazu; Fujioka, Shinsuke; Shimomura, Masashi; Nakai, Yuki; Kimura, Yasuko; Yasuda, Yuzuri; Nishimura, Hiroaki; Norimatsu, Takayoshi; Nishihara, Katsunobu; Miyanaga, Noriaki; Izawa, Yasukazu; Mima, Kunioki [Institute of Laser Engineering, Osaka University, 2-6 Yamada-Oka, Suita, Osaka 565-0871 Japan (Japan); Namba, Shinichi [Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8527 (Japan); Tanuma, Hajime; Ohashi, Hayato; Suda, Shintaro [Department of Physics, Tokyo Metropolitan University, Hachioji, Tokyo 192-0397 (Japan); Sunahara, Atsushi [Institute of Laser Technology, 2-6 Yamada-Oka, Suita, Osaka 565-0871 Japan (Japan)

2008-03-17

336

Experiment analysis of freeform testing based on absolute testing method  

NASA Astrophysics Data System (ADS)

Requirements for the measurement resolution in the sub-nanometer range have become quite common which includes not only the repeatability or reproducibility but also the absolute measurement accuracy. The freeform lens for wavefront compensating contains some medium spatial frequency terms. The wavefront error of lithographic object lens is very small. One method to reduce the wavefront error of lithographic object lens is to use the freeform lens. The freeform lens for compensation needs more accuracy than the object lens. We can also use freeform lens of sphere or aspheric for compensation. The testing accuracy of sphere and aspheric lens are hard to achieve 1nm. The sphere and aspheric will contain the power term and are hard to find the cat-eye. The ion beam figure system (IBF) is the best polishing machine for nanometer manufacture which will polish the PV of 2um for several weeks even months. Usually we use the PV 200nm lens for compensation. So the freeform for compensation looks like a flat. In this paper we will show the testing experiment of the freeform and the testing problem. The freeform surface is created by 66 Zernike polynomials which are based on the flat lens. The freeform flat is polished by the ion figuring machine of NTG. The environment such as temperature, vibration, humidity is controlled well. The Zygo's interferometer Verifire Ashpere with absolute testing method is used to test the freeform. Position Accuracy is a problem in optical testing and manufacture. The high accuracy testing can't be determined by one method, we need the different method to compare the result especially these method will contain some defects. The defects of the recently absolute testing method are discussed.

Jia, Xin; Xu, Fuchao; Xing, Tingwen

2014-07-01

337

Absolute dose calculations for Monte Carlo simulations of radiotherapy beams  

NASA Astrophysics Data System (ADS)

Monte Carlo (MC) simulations have traditionally been used for single field relative comparisons with experimental data or commercial treatment planning systems (TPS). However, clinical treatment plans commonly involve more than one field. Since the contribution of each field must be accurately quantified, multiple field MC simulations are only possible by employing absolute dosimetry. Therefore, we have developed a rigorous calibration method that allows the incorporation of monitor units (MU) in MC simulations. This absolute dosimetry formalism can be easily implemented by any BEAMnrc/DOSXYZnrc user, and applies to any configuration of open and blocked fields, including intensity-modulated radiation therapy (IMRT) plans. Our approach involves the relationship between the dose scored in the monitor ionization chamber of a radiotherapy linear accelerator (linac), the number of initial particles incident on the target, and the field size. We found that for a 10 × 10 cm2 field of a 6 MV photon beam, 1 MU corresponds, in our model, to 8.129 × 1013 ± 1.0% electrons incident on the target and a total dose of 20.87 cGy ± 1.0% in the monitor chambers of the virtual linac. We present an extensive experimental verification of our MC results for open and intensity-modulated fields, including a dynamic 7-field IMRT plan simulated on the CT data sets of a cylindrical phantom and of a Rando anthropomorphic phantom, which were validated by measurements using ionization chambers and thermoluminescent dosimeters (TLD). Our simulation results are in excellent agreement with experiment, with percentage differences of less than 2%, in general, demonstrating the accuracy of our Monte Carlo absolute dose calculations.

Popescu, I. A.; Shaw, C. P.; Zavgorodni, S. F.; Beckham, W. A.

2005-07-01

338

Morphology and Absolute Magnitudes of the SDSS DR7 QSOs  

NASA Astrophysics Data System (ADS)

The ESA mission Gaia will furnish a complete census of the Milky Way, delivering astrometrics, dynamics, and astrophysics information for 1 billion stars. Operating in all-sky repeated survey mode, Gaia will also provide measurements of extra-galactic objects. Among the later there will be at least 500,000 QSOs that will be used to build the reference frame upon which the several independent observations will be combined and interpreted. Not all the QSOs are equally suited to fulfill this role of fundamental, fiducial grid-points. Brightness, morphology, and variability define the astrometric error budget for each object. We made use of 3 morphological parameters based on the PSF sharpness, circularity and gaussianity, which enable us to distinguish the "real point-like" QSOs. These parameters are being explored on the spectroscopically certified QSOs of the SDSS DR7, to compare the performance against other morphology classification schemes, as well as to derive properties of the host galaxy. We present a new method, based on the Gaia quasar database, to derive absolute magnitudes, on the SDSS filters domain. The method can be extrapolated all over the optical window, including the Gaia filters. We discuss colors derived from SDSS apparent magnitudes and colors based on absolute magnitudes that we obtained tanking into account corrections for dust extinction, either intergalactic or from the QSO host, and for the Lyman ? forest. In the future we want to further discuss properties of the host galaxies, comparing for e.g. the obtained morphological classification with the color, the apparent and absolute magnitudes, and the redshift distributions.

Coelho, B.; Andrei, A. H.; Antón, S.

2014-10-01

339

Absolute Quantification of Somatic DNA Alterations in Human Cancer - Scott Carter, TCGA Scientific Symposium 2011  

Cancer.gov

Home News and Events Multimedia Library Videos Absolute Quantification of Somatic DNA Alterations in Human Cancer - Scott Carter Absolute Quantification of Somatic DNA Alterations in Human Cancer - Scott Carter, TCGA Scientific Symposium 2011 You

340

Measurement of the absolute solar UV irradiance and variability  

NASA Technical Reports Server (NTRS)

Radiation in the wavelength interval 150-350 nm initiates chemical reactions in the lower mesosphere and the stratosphere through the photodissociation of ambient molecular species. This experiment measures the total solar irradiance, above the Earth's atmosphere, in this wavelength interval, using three spectrometers. Measurements are made from rockets on a once-a-year basis and are used with satellite observations to determine both the absolute irradiance and the long term variability of the sun in the UV. A fourth spectrometer is being added to the payload to measure the emission in the hydrogen Lyman-alpha emission at 121.67 nm.

Mentall, James E.

1990-01-01

341

Network topology determination using least absolute value state estimation  

SciTech Connect

In energy control centers, the estimates of the system state can often be affected by errors in the assumptions made about the topology of the network. This paper introduces a technique that avoids making incorrect assumptions about network status by estimating the status of suspect lines as a part of the state estimation process. This is done by introducing additional variables and measurements in the conventional state estimation problem. The success of the method relies on properties of the Least Absolute Value (LAV) estimator (an estimator that minimizes the {ell}{sub 1} norm of the measurement residuals). The performance of the method is demonstrated on standard test systems.

Singh, H.; Alvarado, F.L. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Electrical and Computer Engineering] [Univ. of Wisconsin, Madison, WI (United States). Dept. of Electrical and Computer Engineering

1995-08-01

342

Weighted least absolute value state estimation using interior point methods  

SciTech Connect

This paper addresses the application of interior point methods to the Weighted Least Absolute Value state estimation problem. Interior point methods are applied to the primal and dual formulations of the problem. The dual formulation involves solving least squares problems identical in structure to those used in conventional Weighted Least Squares state estimation. The dual formulations also provides an initial feasible interior point without any extra effort. Computational issues that are critical to the success of interior point methods are addressed and test results on standard systems are provided.

Singh, H.; Alvarado, F.L. (Univ. of Wisconsin, Madison, WI (United States). Dept. of Electrical and Computer Engineering)

1994-08-01

343

Absolute photoionization cross-section of the methyl radical.  

SciTech Connect

The absolute photoionization cross-section of the methyl radical has been measured using two completely independent methods. The CH{sub 3} photoionization cross-section was determined relative to that of acetone and methyl vinyl ketone at photon energies of 10.2 and 11.0 eV by using a pulsed laser-photolysis/time-resolved synchrotron photoionization mass spectrometry method. The time-resolved depletion of the acetone or methyl vinyl ketone precursor and the production of methyl radicals following 193 nm photolysis are monitored simultaneously by using time-resolved synchrotron photoionization mass spectrometry. Comparison of the initial methyl signal with the decrease in precursor signal, in combination with previously measured absolute photoionization cross-sections of the precursors, yields the absolute photoionization cross-section of the methyl radical; {sigma}{sub CH}(10.2 eV) = (5.7 {+-} 0.9) x 10{sup -18} cm{sup 2} and {sigma}{sub CH{sub 3}}(11.0 eV) = (6.0 {+-} 2.0) x 10{sup -18} cm{sup 2}. The photoionization cross-section for vinyl radical determined by photolysis of methyl vinyl ketone is in good agreement with previous measurements. The methyl radical photoionization cross-section was also independently measured relative to that of the iodine atom by comparison of ionization signals from CH{sub 3} and I fragments following 266 nm photolysis of methyl iodide in a molecular-beam ion-imaging apparatus. These measurements gave a cross-section of (5.4 {+-} 2.0) x 10{sup -18} cm{sup 2} at 10.460 eV, (5.5 {+-} 2.0) x 10{sup -18} cm{sup 2} at 10.466 eV, and (4.9 {+-} 2.0) x 10{sup -18} cm{sup 2} at 10.471 eV. The measurements allow relative photoionization efficiency spectra of methyl radical to be placed on an absolute scale and will facilitate quantitative measurements of methyl concentrations by photoionization mass spectrometry.

Taatjes, C. A.; Osborn, D. L.; Selby, T.; Meloni, G.; Fan, H.; Pratt, S. T.; Chemical Sciences and Engineering Division; SNL

2008-01-01

344

Flash Card Pass-Around (Intro to Integers, absolute value)  

NSDL National Science Digital Library

To give them an opportunity to practice double negatives and absolute values, students do several practice problems with them, but with a twist. Every student gets a flashcard with a problem on it and they are told that they need to trade their card with somebody else until they have seen all 12 problems. In this way, every student practices 12 distinct problems and must work with other students to get the cards they need, which promotes student interaction. When the activity is finished, students come together as a class to discuss the answers they got to each of the problems.

2010-01-01

345

Management of palatal vascular malformation using absolute ethanol sclerotherapy  

PubMed Central

Arteriovenous malformation is treated by variety of techniques over the years. Sclerotherapy is considered an effective and conservative technique for the treatment of benign vascular lesions and replaced the traditional role of surgical therapy, especially for the venous lesions that are surgically difficult or at inaccessible areas. Absolute ethanol was adopted as a new sclerosant agent for this complex form of venous defects to improve overall treatment results with acceptable morbidity and recurrence rates. Sclerotherapy has the advantage of no external scaring, low cost, and few complications in comparison to the surgical treatment. PMID:24765386

El-Hakim, Ibrahim; Alyamani, Ahmed

2011-01-01

346

Absolute Polarization Measurement Using a Vector Light Shift  

NASA Astrophysics Data System (ADS)

We have measured the vector light shift due to a cavity built-up optical lattice by using a variation of the Hanle effect with trapped Cs atoms, where the time-evolving population of all magnetic sublevels is measured in situ. The measurement is linearly sensitive to the electric field of the nonlinearly polarized light, which allows unprecedented sensitivity to absolute linear polarization quality, to the level of 10-10 in fractional intensity. Our approach to measuring and improving linear polarization can be applied to electron electric dipole moment searches, optical lattice clocks, magnetometery, and quantum computing.

Zhu, Kunyan; Solmeyer, Neal; Tang, Cheng; Weiss, David S.

2013-12-01

347

Absolute calibration in grazing incidence interferometry via rotational averaging  

SciTech Connect

Interferometry in grazing incidence can be used to test cylindrical mantle surfaces. The absolute accuracy of the resulting surface profiles is limited by systematic wavefront aberrations caused in the interferometer, in particular due to an inversion of the test wavefront in an interferometer using diffractive beam splitters. For cylindrical specimens, a calibration method using four positions has therefore been investigated. This test is combined with another method of optical metrology: the rotational averaging procedure. The implementation for grazing incidence is described and measurement results for hollow cylinders are presented. The gain in accuracy is demonstrated.

Mantel, Klaus; Lamprecht, Juergen; Lindlein, Norbert; Schwider, Johannes

2006-06-01

348

First absolute mass measurements of short-lived isotopes  

NASA Astrophysics Data System (ADS)

Absolute mass measurements of short-lived isotopes have been performed at the on-line mass separator ISOLDE at CERN by determining the cyclotron frequencies of ions confined in a Penning trap. The cyclotron frequencies for77,78,85,86,88Rb and88Sr ions could be determined with a resolving power of 3×105 and an accuracy of better than 10-6, which corresponds to 100 keV for mass A=100. The shortest-lived isotope under investigation was77Rb with a half-life of 3.7 min. The resonances obtained for the isobars88Rb and88Sr were clearly resolved.

Bollen, G.; Dabkiewicz, P.; Egelhof, P.; Hilberath, T.; Kalinowsky, H.; Kern, F.; Schnatz, H.; Schweikhard, L.; Stolzenberg, H.; Moore, R. B.; Kluge, H.-J.; Temmer, G. M.; Ulm, G.

1987-12-01

349

Absolute neutrino mass scale determination with the KATRIN experiment  

SciTech Connect

The aim of the KArlsruhe TRItium Neutrino experiment KATRIN is the direct and model independent determination of the absolute neutrino mass scale down to 0.2 eV. For this purpose, the integral electron energy spectrum will be measured close to the endpoint of molecular tritium beta decay. The electrostatic retardation method with magnetic adiabatic collimation (MAC-E filter) combines high energy resolution with high statistics and small background. The various components of the experiment (gaseous tritium source, pumping-transport system, pre- and main spectrometer, detector and rear system) are reviewed.

Glueck, F. [Universitaet Karlsruhe (Thailand), Institut fuer Experimentelle Kernphysik (Germany)]|[Research Institute for Nuclear and Particle Physics, Theory Dep., Budapest (Hungary)

2007-10-12

350

Quantum bath refrigeration towards absolute zero: challenging the unattainability principle.  

PubMed

A minimal model of a quantum refrigerator, i.e., a periodically phase-flipped two-level system permanently coupled to a finite-capacity bath (cold bath) and an infinite heat dump (hot bath), is introduced and used to investigate the cooling of the cold bath towards absolute zero (T=0). Remarkably, the temperature scaling of the cold-bath cooling rate reveals that it does not vanish as T?0 for certain realistic quantized baths, e.g., phonons in strongly disordered media (fractons) or quantized spin waves in ferromagnets (magnons). This result challenges Nernst's third-law formulation known as the unattainability principle. PMID:23002817

Kolá?, M; Gelbwaser-Klimovsky, D; Alicki, R; Kurizki, G

2012-08-31

351

Absolute magnetic helicity and the cylindrical magnetic field  

SciTech Connect

The different magnetic helicities conserved under conditions of perfect electrical conductivity are expressions of the fundamental property that every evolving fluid surface conserves its net magnetic flux. This basic hydromagnetic point unifies the well known Eulerian helicities with the Lagrangian helicity defined by the conserved fluxes frozen into a prescribed set of disjoint toroidal tubes of fluid flowing as a permanent partition of the entire fluid [B. C. Low, Astrophys. J. 649, 1064 (2006)]. This unifying theory is constructed from first principles, beginning with an analysis of the Eulerian and Lagrangian descriptions of fluids, separating the ideas of fluid and magnetic-flux tubes and removing the complication of the magnetic vector potential's free gauge from the concept of helicity. The analysis prepares for the construction of a conserved Eulerian helicity, without that gauge complication, to describe a 3D anchored flux in an upright cylindrical domain, this helicity called absolute to distinguish it from the well known relative helicity. In a version of the Chandrasekhar-Kendall representation, the evolving field at any instant is a unique superposition of a writhed, untwisted axial flux with a circulating flux of field lines all closed and unlinked within the cylindrical domain. The absolute helicity is then a flux-weighted sum of the writhe of that axial flux and its mutual linkage with the circulating flux. The absolute helicity is also conserved if the frozen-in field and its domain are continuously deformed by changing the separation between the rigid cylinder-ends with no change of cylinder radius. This hitherto intractable cylindrical construction closes a crucial conceptual gap for the fundamentals to be complete at last. The concluding discussion shows the impact of this development on our understanding of helicity, covering (i) the helicities of wholly contained and anchored fields; (ii) the Eulerian and Lagrangian descriptions of field evolution; (iii) twist as a topological property of solenoidal fields versus the linkage properties of open and closed discrete curves treated by Gauss, Caligarneau, Berger, and Prior; and (iv) the change of absolute helicity by resistive diffusion. These are important hydromagnetic properties of twisted magnetic fields in the million-degree hot, highly conducting corona of the Sun.

Low, B. C. [High Altitude Observatory, National Center for Atmospheric Research, Boulder, Colorado 80307 (United States)

2011-05-15

352

Absolute calibration of a CCD camera with twin beams  

E-print Network

We report on the absolute calibration of a CCD camera by exploiting quantum correlation. This novel method exploits a certain number of spatial pairwise quantum correlated modes produced by spontaneous parametric-down-conversion. We develop a measurement model taking into account all the possible source of losses and noise that are not related to the quantum efficiency,accounting for all the uncertainty contributions, and we reach the relative uncertainty of 0.3% in low photon flux regime. This represents a significant step forward for the characterizaion of (scientific) CCDs used in mesoscopic light regime.

I. Ruo-Berchera; A. Meda; I. P. Degiovanni; G. Brida; M. L. Rastello; M. Genovese

2014-05-07

353

Prelaunch absolute radiometric calibration of LANDSAT-4 protoflight Thematic Mapper  

NASA Technical Reports Server (NTRS)

Results are summarized and analyzed from several prelaunch tests with a 122 cm integrating sphere used as part of the absolute radiometric calibration experiments for the protoflight TM sensor carried on the LANDSAT-4 satellite. The calibration procedure is presented and the radiometric sensitivity of the TM is assessed. The internal calibrator and dynamic range after calibration are considered. Tables show dynamic range after ground processing, spectral radiance to digital number and digital number to spectral radiance values for TM bands 1, 2, 3, 4, 5, 7 and for channel 4 of band 6.

Barker, J. L.; Ball, D. L.; Leung, K. C.; Walker, J. A.

1984-01-01

354

Absolute Earthquake Locations with Differential Data By William Menke and David Schaff  

E-print Network

Absolute Earthquake Locations with Differential Data By William Menke and David Schaff Lamont the commonly-held wisdom that "you can't determine the absolute location of earthquakes using the double differential arrival time data can, in principle, be used to determine the absolute locations of earthquakes

Menke, William

355

A Special Application of Absolute Value Techniques in Authentic Problem Solving  

ERIC Educational Resources Information Center

There are at least five different equivalent definitions of the absolute value concept. In instances where the task is an equation or inequality with only one or two absolute value expressions, it is a worthy educational experience for learners to solve the task using each one of the definitions. On the other hand, if more than two absolute value…

Stupel, Moshe

2013-01-01

356

Electrical Resistivity and Thermal Conductivity of Nine Selected AISI Stainless Steels.  

National Technical Information Service (NTIS)

This technical report reviews the available experimental data and information on the electrical resistivity and thermal conductivity of nine selected AISI stainless steels and presents the recommended values from near absolute zero (1 K) to above the melt...

C. Y. Ho T. K. Chu

1977-01-01

357

Absolute cross sections for elastic electron scattering from 3-hydroxytetrahydrofuran  

NASA Astrophysics Data System (ADS)

The results of measurements and calculations of absolute cross sections for elastic electron scattering from the 3-hydroxytetrahydrofuran (3hTHF) (C4H8O2) molecule are reported. The measurements were performed using a crossed beam experimental setup, for an incident electron energy range of 40 300 eV and an overall scattering angle range of 10° 110°. Relative differential cross sections (DCSs) were measured both as a function of the angle and the incident energy and the absolute DCSs were determined using the relative flow technique. The calculations of molecular cross sections are based on a corrected form of the independent-atom method, known as the screen corrected additivity rule (SCAR) procedure and using an improved quasifree absorption model. Additional calculations are also done to investigate the influence of rotational excitations and low-angular behavior of SCAR DCSs. The calculated dataset includes differential, integral and total cross sections in the energy range from 5 eV to 10 000 eV. The present results are discussed regarding the most recent low-energy elastic DCSs for 3hTHF (Vizcaino et al 2008 New J. Phys. 10 053002), as well as the recent DCSs for molecules of similar structure (tetrahydrofuran and tetrahydrofurfuryl alcohol).

Milosavljevi?, A. R.; Blanco, F.; Maljkovi?, J. B.; Ševi?, D.; García, G.; Marinkovi?, B. P.

2008-10-01

358

Enabling Dark Energy and Beyond Science with Precise Absolute Photometry  

NASA Astrophysics Data System (ADS)

We have obtain WFC3/IR observations of 15 carefully selected stars with the immediate objective of establishing their Absolute Physical Flux (ABF), and an ultimate goal of achieving the sub-1% absolute photometric accuracies required by Dark Energy science with JWST and other facilities. Even with the best data available, the current determination of ABFs is plagued by the reliance on the Vega photometric system, which is known to be problematic primarily due to the fact that Vega is a pole-on rapid rotator with an infrared excess from its circumstellar disk! which makes it difficult to model. Vega is also far too bright for large aperture telescopes. In an effort to remedy these difficulties, teams from the National Institute of Standards (NIST), the University of New Mexico, Johns Hopkins University and STScI have begun to develop a catalog of stars that have spectral energy distributions that are tied directly to NIST (diode) standards with very precisely determined physical characteristics. A key element in this pursuit has been the efforts at STScI to measure the spectra of many of these objects with STIS. We discuss our program to extend this effort into the near-IR which is crucial to reliably extend the SEDs to longer wavelengths, including the mid IR.

Deustua, Susana E.; Hines, D. C.; Bohlin, R.; Gordon, K. D.

2014-01-01

359

Absolute counting of neutrophils in whole blood using flow cytometry.  

PubMed

Absolute neutrophil count (ANC) is used clinically to monitor physiological dysfunctions such as myelosuppression or infection. In the research laboratory, ANC is a valuable measure to monitor the evolution of a wide range of disease states in disease models. Flow cytometry (FCM) is a fast, widely used approach to confidently identify thousands of cells within minutes. FCM can be optimised for absolute counting using spiked-in beads or by measuring the sample volume analysed. Here we combine the 1A8 antibody, specific for the mouse granulocyte protein Ly6G, with flow cytometric counting in straightforward FCM assays for mouse ANC, easily implementable in the research laboratory. Volumetric and Trucount™ bead assays were optimized for mouse neutrophils, and ANC values obtained with these protocols were compared to ANC measured by a dual-platform assay using the Orphee Mythic 18 veterinary haematology analyser. The single platform assays were more precise with decreased intra-assay variability compared with ANC obtained using the dual protocol. Defining ANC based on Ly6G expression produces a 15% higher estimate than the dual protocol. Allowing for this difference in ANC definition, the flow cytometry counting assays using Ly6G can be used reliably in the research laboratory to quantify mouse ANC from a small volume of blood. We demonstrate the utility of the volumetric protocol in a time-course study of chemotherapy induced neutropenia using four drug regimens. © 2014 International Society for Advancement of Cytometry. PMID:24995861

Brunck, Marion E G; Andersen, Stacey B; Timmins, Nicholas E; Osborne, Geoffrey W; Nielsen, Lars K

2014-12-01

360

Absolute Quantification of Selected Proteins in the Human Osteoarthritic Secretome  

PubMed Central

Osteoarthritis (OA) is characterized by a loss of extracellular matrix which is driven by catabolic cytokines. Proteomic analysis of the OA cartilage secretome enables the global study of secreted proteins. These are an important class of molecules with roles in numerous pathological mechanisms. Although cartilage studies have identified profiles of secreted proteins, quantitative proteomics techniques have been implemented that would enable further biological questions to be addressed. To overcome this limitation, we used the secretome from human OA cartilage explants stimulated with IL-1? and compared proteins released into the media using a label-free LC-MS/MS-based strategy. We employed QconCAT technology to quantify specific proteins using selected reaction monitoring. A total of 252 proteins were identified, nine were differentially expressed by IL-1 ? stimulation. Selected protein candidates were quantified in absolute amounts using QconCAT. These findings confirmed a significant reduction in TIMP-1 in the secretome following IL-1? stimulation. Label-free and QconCAT analysis produced equivocal results indicating no effect of cytokine stimulation on aggrecan, cartilage oligomeric matrix protein, fibromodulin, matrix metalloproteinases 1 and 3 or plasminogen release. This study enabled comparative protein profiling and absolute quantification of proteins involved in molecular pathways pertinent to understanding the pathogenesis of OA. PMID:24132152

Peffers, Mandy J.; Beynon, Robert J.; Clegg, Peter D.

2013-01-01

361

Closed-loop step motor control using absolute encoders  

SciTech Connect

A multi-axis, step motor control system was developed to accurately position and control the operation of a triple axis spectrometer at the High Flux Isotope Reactor (HFIR) located at Oak Ridge National Laboratory. Triple axis spectrometers are used in neutron scattering and diffraction experiments and require highly accurate positioning. This motion control system can handle up to 16 axes of motion. Four of these axes are outfitted with 17-bit absolute encoders. These four axes are controlled with a software feedback loop that terminates the move based on real-time position information from the absolute encoders. Because the final position of the actuator is used to stop the motion of the step motors, the moves can be made accurately in spite of the large amount of mechanical backlash from a chain drive between the motors and the spectrometer arms. A modified trapezoidal profile, custom C software, and an industrial PC, were used to achieve a positioning accuracy of 0.00275 degrees of rotation. A form of active position maintenance ensures that the angles are maintained with zero error or drift.

Hicks, J.S.; Wright, M.C.

1997-08-01

362

Absolute and relative quantification of RNA modifications via biosynthetic isotopomers.  

PubMed

In the resurging field of RNA modifications, quantification is a bottleneck blocking many exciting avenues. With currently over 150 known nucleoside alterations, detection and quantification methods must encompass multiple modifications for a comprehensive profile. LC-MS/MS approaches offer a perspective for comprehensive parallel quantification of all the various modifications found in total RNA of a given organism. By feeding (13)C-glucose as sole carbon source, we have generated a stable isotope-labeled internal standard (SIL-IS) for bacterial RNA, which facilitates relative comparison of all modifications. While conventional SIL-IS approaches require the chemical synthesis of single modifications in weighable quantities, this SIL-IS consists of a nucleoside mixture covering all detectable RNA modifications of Escherichia coli, yet in small and initially unknown quantities. For absolute in addition to relative quantification, those quantities were determined by a combination of external calibration and sample spiking of the biosynthetic SIL-IS. For each nucleoside, we thus obtained a very robust relative response factor, which permits direct conversion of the MS signal to absolute amounts of substance. The application of the validated SIL-IS allowed highly precise quantification with standard deviations <2% during a 12-week period, and a linear dynamic range that was extended by two orders of magnitude. PMID:25129236

Kellner, Stefanie; Ochel, Antonia; Thüring, Kathrin; Spenkuch, Felix; Neumann, Jennifer; Sharma, Sunny; Entian, Karl-Dieter; Schneider, Dirk; Helm, Mark

2015-02-01

363

Accurate absolute parameters of the binary system V4089 Sgr  

E-print Network

We carried out a spectroscopic-photometric analysis of the binary V4089 Sgr with the aim to obtain absolute masses and radii of the components and to contrast these parameters with stellar evolution theoretical models. We took high-resolution spectra and measured radial velocity using standard cross-correlations and a technique of spectral disentangling. Absolute parameters of the components were determined through the simultaneous fitting of measured radial velocities and Geneva photometric data available in the literature. In this way we obtained Ma=2.584+-0.008 Msun, Mb=1.607+-0.007 Msun, Ra=3.959+-0.013 Rsun, and Rb=1.605+-0.016 Rsun. The comparison of these parameters with two grids of theoretical models led to estimate narrow ranges of possible values for system metallicity and age. According circularization theory it is not expected that the binary had been achieved a circular orbit as a result of tidal friction, so the null eccentricity found is an interesting fact. On the other hand, we measured proj...

Veramendi, M E

2014-01-01

364

Redetermination and absolute configuration of 7?-hy-droxy-royleanone  

PubMed Central

The title compound [systematic name: 7?,12-dihy­droxy-8,12-abietadiene,11,14-dione or (4bS,8aS,10R)-3,10-dihy­droxy-2-isopropyl-4b,8,8-trimethyl-1,4,4b,5,6,7,8,8a,9,10-deca­hydro­phenanthrene-1,4-dione], C20H28O4, is an abietane diterpen­oid, which was isolated from the roots of Premna obtusifolia (Verbenaceae). Its crystal structure has been reported previously [Chen et al. (2000 ?). Jiegou Huaxue, 19, 122–125], but the absolute configuration could not be determined using data collected with Mo radiation. This redetermination using Cu radiation shows the the absolute configurations of the stereogenic centres at positions 4b, 8a and 10 to be S, S and R, respectively. Two intra­molecular O—H?O hydrogen bonds [one generating an S(5) ring and one generating an S(6) ring] and a number of short C—H?O contacts occur. In the crystal, mol­ecules are linked into infinite chains propagating in [100] by O—H?O hydrogen bonds and weak C—H?O inter­actions. PMID:21587809

Razak, Ibrahim Abdul; Salae, Abdul Wahab; Chantrapromma, Suchada; Karalai, Chatchanok; Fun, Hoong-Kun

2010-01-01

365

Interpretation of absolute measures of disease risk in comparative research.  

PubMed

When comparing two groups, one receiving an experimental intervention and the other a placebo or nothing, researchers often wish to assess the disparity in risk of experiencing an event of interest, such as onset of disease. Relative risk, relative risk reduction, and odds ratio are often used to measure the association between potential benefit or harm and the intervention. However, these summary measures reflect relative disparities and are perhaps less useful in clinical practice than measures of absolute benefit or harm. We demonstrate that relative risk reduction is unaffected by the risk of an event in the control group and hence may either overestimate or underestimate the treatment effect. Absolute risk reduction accounts for the baseline control group event rate and is a more realistic quantification of treatment effect than relative measures. Number needed to treat (NNT) estimates the therapeutic effort needed to prevent one additional adverse event. NNT incorporates both relative risk reduction and the event rate without treatment. For a given relative risk reduction, we demonstrate the NNT will increase as the control event rate decreases. Thus, NNT has more-obvious implications for clinical decision making than risk estimates expressed in relative terms. PMID:17549653

Replogle, William H; Johnson, William D

2007-06-01

366

The absolute radiometric calibration of Terra imaging sensors: MODIS, MISR, and ASTER  

NASA Astrophysics Data System (ADS)

The Terra spacecraft contains five Earth-observation instruments, three of which are multispectral imaging sensors that complement each other in spectral and spatial coverage. The Moderate Resolution Imaging Spectroradiometer (MODIS) has 36 channels ranging from 0.4-14.4 ?m, with spatial resolutions of 250, 500, and 1000 m. The Multi-angle Imaging SpectroRadiometer (MISR) uses individual imaging sensors to view the earth at nine discreet angles. Each radiometer has four channels in the visible and near infrared (VNIR), and the nadir-viewing camera has a spatial resolution of 275 m. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) was designed with fourteen bands ranging from 0.5-11.6 ?m. It is the high-resolution sensor on Terra, with a spatial resolution of 15 m in the VNIR, and 30 m in the shortwave infrared (SWIR). This work describes the vicarious techniques used to perform the absolute radiometric calibration of MODIS, MISR, and ASTER in the solar-reflective region (0.4-2.5 ?m). It includes the reflectance-based approach, which uses ground-based personnel to make in situ measurements during the time of overpass. It also includes more recent results that were obtained using the University of Arizona's automated Radiometric Calibration Test Site (RadCaTS) at Railroad Valley, Nevada. In addition to the absolute radiometric calibration of Terra sensors, RadCaTS is used to perform the cross comparison of MODIS, MISR, and ASTER with Landsat 7 ETM+ and Landsat 8 OLI.

Czapla-Myers, Jeffrey; Thome, Kurtis; Anderson, Nikolaus; Biggar, Stuart

2014-10-01

367

Laser studies of methyl radical reactions with Cl2 and Br2: Absolute rate constants, product vibrational excitation, and hot radical reactions  

Microsoft Academic Search

Reactions of methyl radicals with Cl2 and Br2 are studied by pulsed laser dissociation of CH3I followed by time-resolved detection of infrared vibrational fluorescence from the C–H stretch modes of the methyl halide product. This method provides a determination of the absolute rate constants for the methyl radical reactions. The rate constants for thermal reactions of CH3 with Cl2 and

Laurie J. Kovalenko; Stephen R. Leone

1984-01-01

368

A novel diffractive encoding principle for absolute optical encoders  

NASA Astrophysics Data System (ADS)

Rotary and linear position sensors are used in numerous manufacturing and automotive applications, where cost effectiveness and the ability of integration are major goals. To meet the increasing demand for competitive optical rotary encoders, in recent years a novel type of optical encoders have been proposed and demonstrated using a micro grating based encoding scheme. This proceeding will give details on the operation principle of this novel kind of position encoder and will show its performance on two exemplary implementations: A compact absolute rotary encoder with a micro-structured plastic disc, which can be manufactured in a conventional and cost effective DVD-molding process and a linear encoder which is based on a pseudo-random coding scheme. The implementation as well as results from their experimental characterization are presented.

Hopp, D.; Wibbing, D.; Pruss, C.; Osten, W.; Binder, J.; Schinköthe, W.; Sterns, F.; Seybold, J.; Fritz, K.-P.; Mayer, V.; Kück, H.

2011-05-01

369

Absolute stellar photometry on moderate-resolution FPA images  

USGS Publications Warehouse

An extensive database of star (and Moon) images has been collected by the ground-based RObotic Lunar Observatory (ROLO) as part of the US Geological Survey program for lunar calibration. The stellar data are used to derive nightly atmospheric corrections for the observations from extinction measurements, and absolute calibration of the ROLO sensors is based on observations of Vega and published reference flux and spectrum data. The ROLO telescopes were designed for imaging the Moon at moderate resolution, thus imposing some limitations for the stellar photometry. Attaining accurate stellar photometry with the ROLO image data has required development of specialized processing techniques. A key consideration is consistency in discriminating the star core signal from the off-axis point spread function. The analysis and processing methods applied to the ROLO stellar image database are described. ?? 2009 BIPM and IOP Publishing Ltd.

Stone, T. C.

2009-01-01

370

Absolute calibration of fiber-coupled single-photon detector.  

PubMed

We show a setup for characterising the efficiency of a single-photon-detector absolutely and with a precision better than 1%. Since the setup does not rely on calibrated devices and can be implemented with standard-optic components, it can be realised in any laboratory. Our approach is based on an Erbium-Doped-Fiber-Amplifier (EDFA) radiometer as a primary measurement standard for optical power, and on an ultra-stable source of spontaneous emission. As a proof of principle, we characterise the efficiency of an InGaAs/InP single-photon detector. We verified the correctness of the characterisation with independent measurements. In particular, the measurement of the optical power made with the EDFA radiometer has been compared to that of the Federal Institute of Metrology using a transfer power meter. Our approach is suitable for frequent characterisations of high-efficient single-photon detectors. PMID:25089427

Lunghi, Tommaso; Korzh, Boris; Sanguinetti, Bruno; Zbinden, Hugo

2014-07-28

371

State estimation and absolute image registration for geosynchronous satellites  

NASA Technical Reports Server (NTRS)

Spacecraft state estimation and the absolute registration of Earth images acquired by cameras onboard geosynchronous satellites are described. The basic data type of the procedure consists of line and element numbers of image points called landmarks whose geodetic coordinates, relative to United States Geodetic Survey topographic maps, are known. A conventional least squares process is used to estimate navigational parameters and camera pointing biases from observed minus computed landmark line and element numbers. These estimated parameters along with orbit and attitude dynamic models are used to register images, using an automated grey level correlation technique, inside the span represented by the landmark data. In addition, the dynamic models can be employed to register images outside of the data span in a near real time mode. An important application of this mode is in support of meteorological studies where rapid data reduction is required for the rapid tracking and predicting of dynamic phenomena.

Nankervis, R.; Koch, D. W.; Sielski, H.

1980-01-01

372

Upgrade of absolute extreme ultraviolet diagnostic on J-TEXTa)  

NASA Astrophysics Data System (ADS)

The absolute extreme ultraviolet (AXUV) diagnostic system is used for radiation observation on J-TEXT tokamak [J. Zhang, G. Zhuang, Z. J. Wang, Y. H. Ding, X. Q. Zhang, and Y. J. Tang, Rev. Sci. Instrum. 81, 073509 (2010)]. The upgrade of the AXUV system is aimed to improve the spatial resolution and provide a three-dimensional image on J-TEXT. The new system consists of 12 AXUV arrays (4 AXUV16ELG arrays, 8 AXUV20ELG arrays). The spatial resolution in the cross-section is 21 mm for the AXUV16ELG arrays and 17 mm for the AXUV20ELG arrays. The pre-amplifier is also upgraded for a higher signal to noise ratio. By upgrading the AXUV imaging system, a more accurate observation on the radiation information is obtained.

Zhang, X. L.; Cheng, Z. F.; Hou, S. Y.; Zhuang, G.; Luo, J.

2014-11-01

373

Absolute stress measurements at the rangely anticline, Northwestern Colorado  

USGS Publications Warehouse

Five different methods of measuring absolute state of stress in rocks in situ were used at sites near Rangely, Colorado, and the results compared. For near-surface measurements, overcoring of the borehole-deformation gage is the most convenient and rapid means of obtaining reliable values for the magnitude and direction of the state of stress in rocks in situ. The magnitudes and directions of the principal stresses are compared to the geologic features of the different areas of measurement. The in situ stresses are consistent in orientation with the stress direction inferred from the earthquake focal-plane solutions and existing joint patterns but inconsistent with stress directions likely to have produced the Rangely anticline. ?? 1972.

de la Cruz, R. V.; Raleigh, C. B.

1972-01-01

374

The chromospherically active binary star EI Eridani I. Absolute dimensions  

E-print Network

We present a detailed determination of the astrophysical parameters of the chromospherically active binary star EI Eridani. Our new radial velocities allow to improve the set of orbital elements and reveal long-term variations of the barycentric velocity. A possible third-body orbit with a period of approximately 19 years is presented. Absolute parameters are determined in combination with the Hipparcos parallax. EI Eri's inclination angle of the rotational axis is confined to 56.0 plus/minus 4.5 degrees, its luminosity class IV is confirmed by its radius of 2.37 plus/minus 0.12 R_Sun. A comparison to theoretical stellar evolutionary tracks suggests a mass of 1.09 plus/minus 0.05 M_Sun and an age of approximately 6.15 Gyr. The present investigation is the basis of our long-term Doppler imaging study of its stellar surface.

A. Washuettl; K. G. Strassmeier; T. Granzer; M. Weber; K. Oláh

2008-09-04

375

Valproate reopens critical-period learning of absolute pitch  

PubMed Central

Absolute pitch, the ability to identify or produce the pitch of a sound without a reference point, has a critical period, i.e., it can only be acquired early in life. However, research has shown that histone-deacetylase inhibitors (HDAC inhibitors) enable adult mice to establish perceptual preferences that are otherwise impossible to acquire after youth. In humans, we found that adult men who took valproate (VPA) (a HDAC inhibitor) learned to identify pitch significantly better than those taking placebo—evidence that VPA facilitated critical-period learning in the adult human brain. Importantly, this result was not due to a general change in cognitive function, but rather a specific effect on a sensory task associated with a critical-period. PMID:24348349

Gervain, Judit; Vines, Bradley W.; Chen, Lawrence M.; Seo, Rubo J.; Hensch, Takao K.; Werker, Janet F.; Young, Allan H.

2013-01-01

376

Variations in the Absolute Ultraviolet Intensities of Polar Coronal Holes  

NASA Astrophysics Data System (ADS)

The well-maintained UVCS/SOHO radiometric calibration is used to determine the variations in the ultraviolet intensities in polar coronal holes between the Solar Cycle 22/23 and Cycle 23/24 minima. The radiometric calibration has been carefully monitored and updated during the mission by observing an ensemble of B stars, which, as a group, are believed to have a stable mean irradiance. These observations, along with data from the freshly calibrated Ultraviolet Coronal Spectrometer on the Spartan 201 satellite in 1998, have been used to determine the changes in the calibration. The Spartan 201 inter-calibration, together with the original laboratory calibration, was used to establish the in-flight absolute radiometric calibration scale. This paper summarizes the in-flight radiometric calibration of UVCS/SOHO and observed variations in polar coronal hole intensities as a function of heliographic height above the poles of the Sun.

Gardner, L. D.; Kohl, J. L.; Cranmer, S. R.; Lin, M.; Panasyuk, A. V.; Uzzo, M.

2010-06-01

377

Absolute configuration of antifibrotic (+)-episesamin isolated from Lindera obtusiloba BLUME.  

PubMed

Fractionation of a 70% ethanolic extract from twigs of Lindera obtusiloba BLUME (Japanese spicebush, Tohaku) yielded five fractions of different polarity. The antifibrotic activity within the chloroform phase was best assessed by an in vitro bioassay using rat hepatic stellate cell (HSC) proliferation and their autocrine transforming growth factor beta (TGF-beta) expression as sensitive fibrosis-associated read out. Chromatography of the chloroform extract on Sephadex LH-20 or liquid-liquid extractions yielded a crystalline compound as an active principle, which was identified from NMR and ESI-MS analyses, its melting point, and its optical rotation as (7S,7'R,8R,8'R)-3,4:3',4'-bis(methylenedioxy)-7,9':7',9-diepoxy-lignane [(+)-episesamin]. X-Ray diffraction confirmed the structure and provided, for the first time, directly its absolute configuration. (+)-Episesamin blocked proliferation and the profibrotic autocrine TGF-beta expression HSC without significant cytotoxicity. PMID:22191210

Trowitzsch-Kienast, Wolfram; Rühl, Martin; Kim, Ki Y; Emmerling, Franziska; Erbenb, Ulrike; Somasundaram, Rajan; Freise, Christian

2011-01-01

378

The Swarm Absolute Scalar Magnetometer Magnetic Cleanliness Program  

NASA Astrophysics Data System (ADS)

The Swarm mission selected by the European Space Agency (ESA) as the 3rd Opportunity mission of the Earth Explorer Program will operate a constellation of three satellites dedicated to the most advanced survey of the Earth's magnetic field and its temporal evolution. The magnetic payload aboard each satellite will consist of a Vector Field Magnetometer (VFM) developed by the Danish National Space Center and an Absolute Scalar Magnetometer (ASM) [1] developed by CEA- LETI in partnership with CNES. This instrument shall provide scalar measurements of the magnetic field for the calibration of the fluxgate vector instrument. As a consequence, its accuracy is crucial for the mission's success, and all the parameters affecting it have been consequently thoroughly investigated. This paper focuses on the magnetic cleanliness program that has been implemented throughout the ASM development phases to guarantee its conformity with the performance requirements, from the instrument's design and manufacture to its final qualification tests.

Alcouffe, F.; Bertrand, F.; Jager, T.; Le Prado, M.; Léger, J.-M.; Fratter, I.

2012-05-01

379

An absolute scale for measuring the utility of money  

NASA Astrophysics Data System (ADS)

Measurement of the utility of money is essential in the insurance industry, for prioritising public spending schemes and for the evaluation of decisions on protection systems in high-hazard industries. Up to this time, however, there has been no universally agreed measure for the utility of money, with many utility functions being in common use. In this paper, we shall derive a single family of utility functions, which have risk-aversion as the only free parameter. The fact that they return a utility of zero at their low, reference datum, either the utility of no money or of one unit of money, irrespective of the value of risk-aversion used, qualifies them to be regarded as absolute scales for the utility of money. Evidence of validation for the concept will be offered based on inferential measurements of risk-aversion, using diverse measurement data.

Thomas, P. J.

2010-07-01

380

Full field imaging based instantaneous hyperspectral absolute refractive index measurement  

SciTech Connect

Multispectral refractometers typically measure refractive index (RI) at discrete monochromatic wavelengths via a serial process. We report on the demonstration of a white light full field imaging based refractometer capable of instantaneous multispectral measurement of absolute RI of clear liquid/gel samples across the entire visible light spectrum. The broad optical bandwidth refractometer is capable of hyperspectral measurement of RI in the range 1.30 1.70 between 400nm 700nm with a maximum error of 0.0036 units (0.24% of actual) at 414nm for a = 1.50 sample. We present system design and calibration method details as well as results from a system validation sample.

Baba, Justin S [ORNL; Boudreaux, Philip R [ORNL

2012-01-01

381

The Absolute Calibration of the EUV Imaging Spectrometer on Hinode  

NASA Astrophysics Data System (ADS)

We investigate the absolute calibration of the EUV Imaging Spectrometer (EIS) on Hinode by comparing EIS full-disk mosaics with irradiance observations from the EUV Variability Experiment on the Solar Dynamics Observatory. We also use extended observations of the quiet corona above the limb combined with a simple differential emission measure model to establish new effective area curves that incorporate information from the most recent atomic physics calculations. We find that changes to the EIS instrument sensitivity are a complex function of both time and wavelength. We find that the sensitivity is decaying exponentially with time and that the decay constants vary with wavelength. The EIS short wavelength channel shows significantly longer decay times than the long wavelength channel.

Warren, Harry P.; Ugarte-Urra, Ignacio; Landi, Enrico

2014-07-01

382

Absolute configuration of chlorosulfolipids from the chrysophyta Ochromonas danica.  

PubMed

We isolated eight chlorosulfolipids (1-8) from the chrysophyta Ochromonas danica (IAM CS-2), including five new chlorosulfolipids (2-5, 8). The planar structures of all the compounds were elucidated by 1D and 2D NMR and ESI-MS/MS analyses. We determined the relative configuration of seven chlorosulfolipids (1-7), including the most commonly known chlorosulfolipid, 2,2,11,13,15,16-hexachlorodocosane-1,14-disulfate (1), by J-based configuration analysis (JBCA). The absolute configuration of each compound was determined using a modified Mosher's method after chemical degradation. 2,2,11,13,15,16-Hexachloro-14-docosanol-1-sulfate (2) was the most toxic to brine shrimp (Artemia salina) larvae (LC(50) 0.27 microg/mL). Compounds 1 and 4-8 were less toxic (LC(50) 2.2-6.9 microg/mL). Compound 3 was not toxic at 30 microg/mL. PMID:19627129

Kawahara, Teppei; Kumaki, Yasuhiro; Kamada, Takashi; Ishii, Takahiro; Okino, Tatsufumi

2009-08-21

383

Thermal engine  

SciTech Connect

A thermal engine utilizing a strip of nitinol material or other thermally responsive shape memory effect material to drive a reciprocating output shaft, said strip of material forming a common wall between two different alternating temperature sources which thermally cycle the material.

Karnes, T.E.; Trupin, R.J.

1984-01-03

384

Absolute proper motion of the Galactic open cluster M 67  

NASA Astrophysics Data System (ADS)

We derived the absolute proper motion (PM) of the old, solar-metallicity Galactic open cluster M 67 using observations collected with CFHT (1997) and with LBT (2007). About 50 galaxies with relatively sharp nuclei allow us to determine the absolute PM of the cluster. We find (?_? cos ?, ?_?)_J2000.0 = (-9.6 ± 1.1, -3.7 ± 0.8) mas yr-1. By adopting a line-of-sight velocity of 33.78 ± 0.18 km s-1, and assuming a distance of 815 ± 50 pc, we explore the influence of the Galactic potential, with and without the bar and/or spiral arms, on the galactic orbit of the cluster. Based on data acquired with the Large Binocular Telescope (LBT) at Mt. Graham, Arizona, under the Commissioning of the Large Binocular Blue Camera. The LBT is an international collaboration among institutions in the United States, Italy and Germany. LBT Corporation partners are the University of Arizona on behalf of the Arizona university system; Istituto Nazionale di Astrofisica, Italy; LBT Beteiligungsgesellschaft, Germany, representing the Max-Planck Society, the Astrophysical Institute Potsdam, and Heidelberg University; the Ohio State University, and the Research Corporation, on behalf of the University of Notre Dame, University of Minnesota and University of Virginia; and on observations obtained at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique of France, and the University of Hawaii.Visiting PhD Student at STScI under the “2008 graduate research assistantship” program.

Bellini, A.; Bedin, L. R.; Pichardo, B.; Moreno, E.; Allen, C.; Piotto, G.; Anderson, J.

2010-04-01

385

Cylindrical Taylor states conserving total absolute magnetic helicity  

NASA Astrophysics Data System (ADS)

The Taylor state of a three-dimensional (3D) magnetic field in an upright cylindrical domain V is derived from first principles as an extremum of the total magnetic energy subject to a conserved, total absolute helicity Habs. This new helicity [Low, Phys. Plasmas 18, 052901 (2011)] is distinct from the well known classical total helicity and relative total helicity in common use to describe wholly-contained and anchored fields, respectively. A given field B, tangential along the cylindrical side of V, may be represented as a unique linear superposition of two flux systems, an axially extended system along V and a strictly transverse system carrying information on field-circulation. This specialized Chandrasekhar-Kendall representation defines Habs and permits a neat formulation of the boundary-value problem (BVP) for the Taylor state as a constant-? force-free field, treating 3D wholly-contained and anchored fields on the same conceptual basis. In this formulation, the governing equation is a scalar integro-partial differential equation (PDE). A family of series solutions for an anchored field is presented as an illustration of this class of BVPs. Past treatments of the constant-? field in 3D cylindrical geometry are based on a scalar Helmholtz PDE as the governing equation, with issues of inconsistency in the published field solutions discussed over time in the journal literature. The constant-? force-free equation reduces to a scalar Helmholtz PDE only as special cases of the 3D integro-PDE derived here. In contrast, the constant-? force-free equation and the scalar Helmholtz PDE are absolutely equivalent in the spherical domain as discussed in Appendix. This theoretical study is motivated by the investigation of the Sun's corona but the results are also relevant to laboratory plasmas.

Low, B. C.; Fang, F.

2014-09-01

386

Absolute declinations with the photoelectric astrolabe at Calern Observatory (OCA)  

NASA Astrophysics Data System (ADS)

A regular observational programme with a photoelectric astrolabe have been performed at ``Observatoire du Calern" (Observatoire de la Côte d'Azur, OCA, phi = +43() o44?55.011?; lambda = -0() h27() m42.44() s, Calern, Caussols, France) for the last twenty years. It has been almost fully automatized between 1984 and 1987. Since 1988 the photoelectric astrolabe was used without any modification. In addition to determining the daily orientation of the local vertical, the yearly analysis of the residuals permits to derive corrections to the used star catalogue \\cite[(Vigouroux et al. 1992)]{vig92}. A global reduction method was applied for the ASPHO observations. The new form of the equations \\cite[(Martin & Leister 1997)]{mar97} give us the possibility of using the entire set of the observing program using data taken at two zenith distances (30() o and 45() o). The program contains about 41648 stars' transits of 269 different stars taken at ``Observatoire du Calern" (OCA). The reduction was based on the HIPPARCOS system. We discuss the possibility of computing absolute declinations through stars belonging simultaneously to the 30() o and 45() o zenith distances programmes. The absolute declination corrections were determined for 185 stars with precision of 0.027arcsec and the value of the determined equator correction is -0.018arcsec +/- 0.005arcsec . The instrumental effects were also determined. The mean epoch is 1995.29. Catalogue only available at CDS in electronic from via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html

Martin, V. A. F.; Leister, N. V.; Vigouroux, G.; Furia, M.; Journet, A.

1999-06-01

387

Absolute Magnitudes of Pan-STARRS 1 Asteroids  

NASA Astrophysics Data System (ADS)

It is well known that the absolute magnitudes (H) in the MPCORB and ASTORB orbital element catalogs suffer from a systematic offset. Juric at al. (2002) found 0.4 mag offset in the SDSS data and detailed light curve studies of WISE asteroids by Pravec et al. (2012) revealed size-dependent offsets of up to 0.5 mag. The offsets are thought to be caused by systematic errors introduced by earlier surveys using different photometric catalogs and filters. The next generation asteroid surveys provide an order of magnitude more asteroids and well-defined and calibrated magnitudes. The Pan-STARRS 1 telescope (PS1) has observed hundreds of thousands asteroids, submitted more than 2 million detections to the Minor Planet Center (MPC) and discovered almost 300 NEOs since the beginning of operations in late 2010. We transformed the observed apparent magnitudes of PS1-detected asteroids from the gP1,rP1,iP1,yP1,zP1 and wP1-bands into Johnson photometric system by assuming the mean S and C-type asteroid color (Fitzsimmons 2011 - personal communication, Schlafly et al. 2012, Magnier et al. 2012 - in preparation) and calculated the absolute magnitude (H) in the V-band and its uncertainty (Bowell et al., 1989) for more than 200,000 known asteroids having on average 6.7 detections per object. The H error with respect to the MPCORB catalog revealed a mean offset of -0.49+0.30 mag in good agreement with published values. We will also discuss the statistical and systematical errors in H and slope parameter G.

Veres, Peter; Jedicke, R.; Denneau, L.; Fitzsimmons, A.; Bolin, B.; Wainscoat, R.; Science Consortium, PS1

2012-10-01

388

Observing absolute gravity change in the Fennoscandian postglacial rebound area  

NASA Astrophysics Data System (ADS)

Absolute gravity measurements in the Fennoscandian postglacial rebound area started already in 1976 when a team from Istituto di Metrología "G. Colonnetti" (Torino) measured six stations with the rise-and-fall gravimeter IMGC (Cannizzo et al., 1978). In 1980 two stations were measured by the team of the AN SSSR from Novosibirsk, using the gravimeter GABL (Arnautov et al., 1982). From the beginning the goal was to establish reference values for future remeasurement in order to detect gravity change due to the postglacial rebound. The maximum uplift rates are 1 cm/yr, which implies a surface gravity change of about -2 microgal/yr. In 1988, regular repeat measurements were began by the Finnish Geodetic Institute (FGI) with the JILAg-5. An important advance was the introduction of FG5 gravimeters into the work by BKG (Frankfurt a/M) and NOAA (Boulder, CO) in 1993. In 2003 annual large-scale campaigns with FG5 gravimeters started, coordinated by the Working Group for Geodynamics of the Nordic Geodetic Commission (NKG). This was prompted by the launch of the GRACE satellite gravity mission, which made it important to collect a comprehensive set of ground-truth values of gravity change during the lifetime of the satellite pair. The initial participation by gravimeter teams of Leibniz Universität Hannover, FGI and BKG has since expanded to include the University of Life Sciences (Ås, Norway) and Lantmäteriet (Gävle, Sweden). At present some 50 sites have repeated absolute measurements and most of them are co-located with continuous GPS. We give an overview of the sites, instrumentation and campaigns, and show examples of results achieved so far.

Mäkinen, J.; Engfeldt, A.; Gitlein, O.; Kaminskis, J.; Klopping, F.; Oja, T.; Paršeliunas, E.; Pettersen, B. R.; Strykowski, G.; Wilmes, H.

2009-04-01

389

THE ABSOLUTE MAGNITUDE OF RRc VARIABLES FROM STATISTICAL PARALLAX  

SciTech Connect

We present the first definitive measurement of the absolute magnitude of RR Lyrae c-type variable stars (RRc) determined purely from statistical parallax. We use a sample of 242 RRc variables selected from the All Sky Automated Survey for which high-quality light curves, photometry, and proper motions are available. We obtain high-resolution echelle spectra for these objects to determine radial velocities and abundances as part of the Carnegie RR Lyrae Survey. We find that M{sub V,RRc} = 0.59 ± 0.10 at a mean metallicity of [Fe/H] = –1.59. This is to be compared with previous estimates for RRab stars (M{sub V,RRab} = 0.76 ± 0.12) and the only direct measurement of an RRc absolute magnitude (RZ Cephei, M{sub V,RRc} = 0.27 ± 0.17). We find the bulk velocity of the halo relative to the Sun to be (W{sub ?}, W{sub ?}, W{sub z} ) = (12.0, –209.9, 3.0) km s{sup –1} in the radial, rotational, and vertical directions with dispersions (?{sub W{sub ?}},?{sub W{sub ?}},?{sub W{sub z}}) = (150.4, 106.1, 96.0) km s{sup -1}. For the disk, we find (W{sub ?}, W{sub ?}, W{sub z} ) = (13.0, –42.0, –27.3) km s{sup –1} relative to the Sun with dispersions (?{sub W{sub ?}},?{sub W{sub ?}},?{sub W{sub z}}) = (67.7,59.2,54.9) km s{sup -1}. Finally, as a byproduct of our statistical framework, we are able to demonstrate that UCAC2 proper-motion errors are significantly overestimated as verified by UCAC4.

Kollmeier, Juna A.; Burns, Christopher R.; Thompson, Ian B.; Preston, George W.; Crane, Jeffrey D.; Madore, Barry F.; Morrell, Nidia; Prieto, José L.; Shectman, Stephen; Simon, Joshua D.; Villanueva, Edward [Observatories of the Carnegie Institution of Washington, 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Szczygie?, Dorota M.; Gould, Andrew [Department of Astronomy, The Ohio State University, 4051 McPherson Laboratory, Columbus, OH 43210 (United States); Sneden, Christopher [Department of Astronomy, University of Texas at Austin, TX 78712 (United States); Dong, Subo [Institute for Advanced Study, 500 Einstein Drive, Princeton, NJ 08540 (United States)

2013-09-20

390

Thermal symmetry of the Markovian master equation  

NASA Astrophysics Data System (ADS)

The quantum Markovian master equation of the reduced dynamics of a harmonic oscillator coupled to a thermal reservoir is shown to possess thermal symmetry. This symmetry is revealed by a Bogoliubov transformation that can be represented by a hyperbolic rotation acting on the Liouville space of the reduced dynamics. The Liouville space is obtained as an extension of the Hilbert space through the introduction of tilde variables used in the thermofield dynamics formalism. The angle of rotation depends on the temperature of the reservoir, as well as the value of Planck’s constant. This symmetry relates the thermal states of the system at any two temperatures. This includes absolute zero, at which purely quantum effects are revealed. The Caldeira-Leggett equation and the classical Fokker-Planck equation also possess thermal symmetry. We compare the thermal symmetry obtained from the Bogoliubov transformation in related fields and discuss the effects of the symmetry on the shape of a Gaussian wave packet.

Tay, B. A.; Petrosky, T.

2007-10-01

391

Thermal symmetry of the Markovian master equation  

SciTech Connect

The quantum Markovian master equation of the reduced dynamics of a harmonic oscillator coupled to a thermal reservoir is shown to possess thermal symmetry. This symmetry is revealed by a Bogoliubov transformation that can be represented by a hyperbolic rotation acting on the Liouville space of the reduced dynamics. The Liouville space is obtained as an extension of the Hilbert space through the introduction of tilde variables used in the thermofield dynamics formalism. The angle of rotation depends on the temperature of the reservoir, as well as the value of Planck's constant. This symmetry relates the thermal states of the system at any two temperatures. This includes absolute zero, at which purely quantum effects are revealed. The Caldeira-Leggett equation and the classical Fokker-Planck equation also possess thermal symmetry. We compare the thermal symmetry obtained from the Bogoliubov transformation in related fields and discuss the effects of the symmetry on the shape of a Gaussian wave packet.

Tay, B. A.; Petrosky, T. [Department of Physics, Faculty of Science, University Putra Malaysia, 43400 UPM Serdang, Selangor (Malaysia); Center for Complex Quantum Systems, University of Texas at Austin, 1 University Station C1600, Austin, Texas 78712 (United States)

2007-10-15

392

On the Error Sources in Absolute Individual Antenna Calibrations  

NASA Astrophysics Data System (ADS)

The two main methods for antenna calibration currently in use, are anechoic chamber measurements on the one hand and outdoor robot calibration on the other hand. Both techniques differ completely in approach, setup and data processing. Consequently, the error sources for both techniques are totally different as well. Except for the (near field) multi path error, caused by the antenna positioning device, that alters results for both calibration methods. But not necessarily with the same order of magnitude. Literature states a (maximum deviation) repeatability for robot calibration of choke ring antennas of 0.5 mm on L1 and 1 mm on L2 [1]. For anechoic chamber calibration, a value of 1.5 mm on L2 for a resistive ground plane antenna can be found in [2]. Repeatability however masks systematic errors linked with the calibration technique. Hence, comparing an individual calibration obtained with a robot to a calibration of the same antenna in an anechoic chamber, may result in differences that surpass these repeatability thresholds. This was the case at least for all six choke ring antennas studied. The order of magnitude of the differences moreover corresponded well to the values given for a LEIAT504GG in [3]. For some error sources, such as the GNSS receiver measurement noise or the VNA measurement noise, estimates can be obtained from manufacturer specifications in data sheets. For other error sources, such as the finite distance between transmit and receive antenna, or the limited attenuation of reflections on wall absorber, back-of-the-envelope calculations can be made to estimate their order of magnitude. For the error due to (near field) multi path this is harder to do, if not impossible. The more because this strongly depends on the antenna type and its mount. Unfortunately it is, again, this (near field) multi path influence that might void the calibration once the antenna is installed at the station. Hence it can be concluded that at present, due to (near field) multi path errors, both during calibration and later on at the station, absolute sub-millimeter positioning with GPS is not (yet) possible. References [1] G. Wübbena, M. Schmitz, G. Boettcher, C. Schumann, "Absolute GNSS Antenna Calibration with a Robot: Repeatability of Phase Variations, Calibration of GLONASS and Determination of Carrier-to-Noise Pattern", International GNSS Service: Analysis Center workshop, 8-12 May 2006, Darmstadt, Germany. [2] P. Zeimetz, H. Kuhlmann, "On the Accuracy of Absolute GNSS Antenna Calibration and the Conception of a New Anechoic Chamber", FIG Working Week 2008, 14-19 June 2008, Stockholm, Sweden. [3] P. Zeimetz, H. Kuhlmann, L. Wanninger, V. Frevert, S. Schön and K. Strauch, "Ringversuch 2009", 7th GNSS-Antennen-Workshop, 19-20 March 2009, Dresden, Germany.

Aerts, Wim; Baire, Quentin; Bilich, Andria; Bruyninx, Carine; Legrand, Juliette

2013-04-01

393

Direct and absolute absorption measurements in optical materials and coatings by laser induced deflection (LID) technique  

NASA Astrophysics Data System (ADS)

Different strategies of the laser induced deflection (LID) technique for direct and absolute absorption measurements are presented. Besides selected strategies for bulk and coating absorption measurements, respectively, a new strategy is introduced allowing the transfer of the LID technique to very small samples and to significantly increase the sensitivity for materials with a very weak photo-thermal response. Additionally, an emphasis is placed on the importance of the calibration procedure. The electrical calibration of the LID setup is compared to two other approaches that use either doped samples or highly absorptive reference samples in combination with numerical simulations. Applying the LID technique, we report on the characterization of AR coated LBO crystals used in high power NIR/VIS laser applications. The comparison of different LBO crystals shows that there are significant differences in both, the AR coating and the LBO bulk absorption. These differences are much larger at 515 nm than at 1030 nm. Absorption spectroscopy measurements combining LID technique with a high power OPO laser system indicate that the coating process affects the LBO bulk absorption properties. Furthermore, the change of the absorption upon 1030 nm laser irradiation of a Nd:YVO4 laser crystal is investigated and compared to recent results. Finally, Ytterbium doped silica raw materials for high power fiber lasers are characterized with respect to the absorption induced attenuation at 1550 nm in order to compare these data with the total attenuation obtained for the subsequently manufactured laser active fibers.

Mühlig, Ch.

2012-01-01

394

Absolute Absorptivity of Single-walled Carbon Nanotubes Employing a Pyroelectric Detector  

NASA Astrophysics Data System (ADS)

Optical properties are important for determining fundamental characteristics of carbon single-walled nanotube (SWNT) samples including purity, chirality, and tube diameter. Previously, we have estimated the volume fraction of metallic versus semiconducting tubes for highly purified SWNT bucky-paper on a pyroelectric detector from spectral responsivity measurements and an effective medium approximation to determine the dielectric function (1). Pyroelectric detector-based measurements are based on the thermalization of photons within the SWNT coating and provide a robust technique for measuring absolute absorptivity at normal incidence. Alternatively, we perform transmissivity measurements of SWNTs by employing a gold-black coated pyroelectric detector. Spectral responsivity measurements are made by direct substitution against a NIST calibrated detector such that quantitative changes in the volume fraction and purity of SWNT samples are revealed. These results will be compared to specular transmissivity measurements made by UV-VIS spectrometry. Raman spectroscopy will also serve to verify nanotube properties. (1) K.E.H. Gilbert, J.H. Lehman, A.C. Dillon and J.L. Blackburn Appl. Phys. Lett. 88, 143122 (2006).

Hurst, Katherine; Dillon, Anne; Lehman, John

2007-03-01

395

The Swarm Absolute Scalar Magnetometers now operating in orbit  

NASA Astrophysics Data System (ADS)

Swarm is one of the Earth Explorer Missions run by the European Space Agency. Its principal goal is to make the best ever survey of the Earth's magnetic field and ionosphere and to study how they vary over space and time. This will be achieved by a constellation of three identical satellites, launched on the 22nd of November 2013. In order to observe the magnetic field thoroughly, each satellite carries two magnetometers: a Vector Field Magnetometer coupled with a star tracker camera, to measure the direction of the magnetic field in space, and an Absolute Scalar Magnetometer (ASM), to measure its intensity. The ASM is the French contribution to the Swarm mission. This new generation instrument, based on the atomic spectroscopy of the helium 4 metastable state, was developed by CEA-Leti (1) in Grenoble with technical assistance and financing from CNES (2) and scientific support from IPGP (3). As the Swarm magnetic reference, the ASM scalar performances are crucial for the mission's success. Thanks to a new dedicated design, the ASM offers the best precision and absolute accuracy ever attained in space, with similar performances all along the orbit. The ASM will thus deliver high resolution scalar measurements at 1 Hz for the in-flight calibration of the vector field data over the 4 year mission. It can also be operated at a much higher sampling rate ("burst" mode at 250 Hz). In addition, on an experimental basis, this instrument also takes vector field measurements, which are being validated jointly by CEA-Leti and IPGP, with support from CNES. This poster presents the capabilities and working principle of this instrument as well as the results of the in-flight verifications carried out during the 3 first months in orbit, including the performances, the last status and future prospects. 1 CEA-Leti : French Atomic Energy and Alternative Energies Commission - Electronics and Information Technology Laboratory 2 CNES : Centre National d'Etudes Spatiales - French Space Agency 3 IPGP : Institut de Physique du Globe de Paris - Paris Institute of Earth Physics

Fratter, Isabelle; Leger, Jean-Michel; Bertrand, François; Jager, Thomas; Hulot, Gauthier

2014-05-01

396

Absolute Abundance of Methane and Water on Mars: Spatial Maps  

NASA Astrophysics Data System (ADS)

We earlier reported ground-based detections of methane on Mars, and presented evidence for local enhancements in its mixing ratio consistent with local release. Our long-slit infrared observations (now extending over two Mars years) sample a wide range of seasons and areocentric longitudes with significant spatial coverage. By orienting the slit North-South on the planet, we obtain simultaneous spectra at many latitudes on Mars. Heretofore, we presented differential abundances using one spectrum as a standard of comparison for spectra taken at other latitudes; this approach provides excellent removal of telluric features at the expense of reducing the intensity of residual spectral lines from Mars. Our differential extractions for water agreed with simultaneous measurements acquired with TES. Our differential extractions for methane implied strong latitudinal gradients - these are contrary to predictions if photochemistry limits the lifetime of methane on Mars, but instead require local release and a much shorter lifetime. The lifetime against destruction cannot be much longer than equator-to-pole transport times imposed by the Hadley circulation (weeks). A shorter lifetime requires that estimated production rates be revised upwards commensurately. The extraction of absolute spectral signatures for Mars requires both special instrumental factors (high sensitivity, high resolving power) and an appropriate spectral synthesis technique. The telluric transmittance spectrum must be synthesized at very high resolution (approaching 100 m/sec), as otherwise the subtraction of synthetic from measured spectra produces unacceptably large residuals. This requires inclusion of mixed line-shape functions for H2O, CH4, and O3, and of pressure shift effects for CH4 and H2O. Here, we present absolute extractions of methane and water, based on such multi-layer atmospheric models for Mars and Earth. We will compare and contrast the new results with our earlier findings. Supported by Grants to MJM from NASA's Planetary Astronomy Program (344-32-51-96) and Astrobiology Program (344-53-51), and NSF RUI Grant AST-0205397 to REN. GLV was supported by the NAS-NRC under the NASA Resident Research Associateship Program.

Mumma, M. J.; Novak, R. E.; Hewagama, T.; Villanueva, G. L.; Bonev, B. P.; DiSanti, M. A.; Smith, M. D.; Dello Russo, N.

2005-08-01

397

On-Orbit Absolute Temperature Calibration Using Multiple Phase Change Materials  

Microsoft Academic Search

NASA's anticipated plan for a mission dedicated to Climate (CLARREO) will hinge upon the ability to fly SI traceable standards that provide irrefutable absolute measurement accuracy. As an example, instrumentation designed to measure spectrally resolved infrared radiances will require high-emissivity calibration blackbodies that have absolute temperature uncertainties of better than 0.045K (3 sigma). A novel scheme to provide absolute calibration

F. A. Best; D. P. Adler; C. Pettersen; H. E. Revercomb; J. H. Perepezko

2009-01-01

398

On-orbit absolute temperature calibration using multiple phase change materials: overview of recent technology advancements  

Microsoft Academic Search

NASA's anticipated plan for a mission dedicated to Climate (CLARREO) will hinge upon the ability to fly SI traceable standards that provide irrefutable absolute measurement accuracy. As an example, instrumentation designed to measure spectrally resolved infrared radiances will require high-emissivity calibration blackbodies that have absolute temperature uncertainties of better than 0.045K (3 sigma). A novel scheme to provide absolute calibration

Fred A. Best; Douglas P. Adler; Claire Pettersen; Henry E. Revercomb; John H. Perepezko

2010-01-01

399

THERMAL RADIATION The type of electromagnetic radiation that is pertinentThe type of electromagnetic radiation that is pertinent  

E-print Network

THERMAL RADIATION The type of electromagnetic radiation that is pertinentThe type of electromagnetic radiation that is pertinent to heat transfer is the thermal radiation emitted as a result is above absolute zero. Everything around us constantlyy emits thermal radiation. 5 The electromagnetic

Kostic, Milivoje M.

400

HF (High Frequency) absolute time of arrival sensing  

NASA Astrophysics Data System (ADS)

In late 1980 questions arose concerning whether the ionosphere was sufficiently stable to allow precisely measured time of arrival of skywave signals to be used for geolocation in the high frequency (HF) band between 2 and 32 MHz. The chief limitation in the accuracy of this type of system is the amount of uncertainty in the ionospheric height estimation and its temporal stability. Traditional ionospheric research resources did not address the issue in sufficient detail and time resolution to be of any assistance. In order to understand the exact nature of the ionospheric uncertainties and to quantify their extent, experimentation was proposed to sense the variation in the refraction height of the ionosphere as it relates to the time of arrival of the HF signal. The objective of this work was to determine the range of environmentally induced errors in a skywave Time Difference of Arrival (TDOA) measurement, thereby bounding the ultimate geolocation accuracy one could expect from this technique. The first experimental measurement system started operation in early 1981. This effort involved establishing a continuous absolute Time of Arrival (TOA) experiment over the one-hop midlatitude path between San Diego, California and Fort Collins, Colorado. The system is fully digital and stabilized with a cesium beam standard. This work was supplemented with vertical incidence sounder data at both ends of the path, a collateral Doppler sensing system, and coincident satellite solar data.

Rose, R. B.

1986-02-01

401

A nonmusical paradigm for identifying absolute pitch possessors  

NASA Astrophysics Data System (ADS)

The ability to identify and reproduce sounds of specific frequencies is remarkable and uncommon. The etiology and defining characteristics of this skill, absolute pitch (AP), have been very controversial. One theory suggests that AP requires a specific type of early musical training and that the ability to encode and remember tones depends on these learned musical associations. An alternate theory argues that AP may be strongly dependent on hereditary factors and relatively independent of musical experience. To date, it has been difficult to test these hypotheses because all previous paradigms for identifying AP have required subjects to employ knowledge of musical nomenclature. As such, these tests are insensitive to the possibility of discovering AP in either nonmusicians or musicians of non-Western training. Based on previous literature in pitch memory, a paradigm is presented that is intended to distinguish between AP possessors and nonpossessors independent of the subjects' musical experience. The efficacy of this method is then tested with 20 classically defined AP possessors and 22 nonpossessors. Data from these groups strongly support the validity of the paradigm. The use of a nonmusical paradigm to identify AP may facilitate research into many aspects of this phenomenon.

Ross, David A.; Olson, Ingrid R.; Marks, Lawrence E.; Gore, John C.

2004-09-01

402

INTERPRETATION OF THE ARCADE 2 ABSOLUTE SKY BRIGHTNESS MEASUREMENT  

SciTech Connect

We use absolutely calibrated data between 3 and 90 GHz from the 2006 balloon flight of the ARCADE 2 instrument, along with previous measurements at other frequencies, to constrain models of extragalactic emission. Such emission is a combination of the cosmic microwave background (CMB) monopole, Galactic foreground emission, the integrated contribution of radio emission from external galaxies, any spectral distortions present in the CMB, and any other extragalactic source. After removal of estimates of foreground emission from our own Galaxy, and an estimated contribution of external galaxies, we present fits to a combination of the flat-spectrum CMB and potential spectral distortions in the CMB. We find 2{sigma} upper limits to CMB spectral distortions of {mu} < 6 x 10{sup -4} and |Y{sub ff}| < 1 x 10{sup -4}. We also find a significant detection of a residual signal beyond that, which can be explained by the CMB plus the integrated radio emission from galaxies estimated from existing surveys. This residual signal may be due to an underestimated galactic foreground contribution, an unaccounted for contribution of a background of radio sources, or some combination of both. The residual signal is consistent with emission in the form of a power law with amplitude 18.4 {+-} 2.1 K at 0.31 GHz and a spectral index of -2.57 {+-} 0.05.

Seiffert, M.; Levin, S. M. [Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Fixsen, D. J.; Kogut, A.; Wollack, E. [University of Maryland, Code 665, Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Limon, M. [Columbia Astrophysics Laboratory, 550W 120th St., Mail Code 5247, New York, NY 10027-6902 (United States); Lubin, P. M. [Physics Department, University of California, Santa Barbara, CA (United States); Mirel, P. [Wyle Informations Systems, Code 665, Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Singal, J. [Kavli Institute for Particle Astrophysics and Cosmology, SLAC National Accelerator Laboratory, Menlo Park, CA 94025 (United States); Villela, T.; Wuensche, C. A., E-mail: Michael.D.Seiffert@jpl.nasa.gov [Instituto Nacional de Pesquisas Espaciais, Divisao de Astrofisica, Caixa Postal 515, 12245-970-Sao Jose dos Campos, SP (Brazil)

2011-06-10

403

Absolute measures of the completeness of the fossil record  

NASA Technical Reports Server (NTRS)

Measuring the completeness of the fossil record is essential to understanding evolution over long timescales, particularly when comparing evolutionary patterns among biological groups with different preservational properties. Completeness measures have been presented for various groups based on gaps in the stratigraphic ranges of fossil taxa and on hypothetical lineages implied by estimated evolutionary trees. Here we present and compare quantitative, widely applicable absolute measures of completeness at two taxonomic levels for a broader sample of higher taxa of marine animals than has previously been available. We provide an estimate of the probability of genus preservation per stratigraphic interval, and determine the proportion of living families with some fossil record. The two completeness measures use very different data and calculations. The probability of genus preservation depends almost entirely on the Palaeozoic and Mesozoic records, whereas the proportion of living families with a fossil record is influenced largely by Cenozoic data. These measurements are nonetheless highly correlated, with outliers quite explicable, and we find that completeness is rather high for many animal groups.

Foote, M.; Sepkoski, J. J. Jr; Sepkoski JJ, J. r. (Principal Investigator)

1999-01-01

404

Absolute and relative pitch: Global versus local processing of chords  

PubMed Central

Absolute pitch (AP) is the ability to identify or produce notes without any reference note. An ongoing debate exists regarding the benefits or disadvantages of AP in processing music. One of the main issues in this context is whether the categorical perception of pitch in AP possessors may interfere in processing tasks requiring relative pitch (RP). Previous studies, focusing mainly on melodic and interval perception, have obtained inconsistent results. The aim of the present study was to examine the effect of AP and RP separately, using isolated chords. Seventy-three musicians were categorized into four groups of high and low AP and RP, and were tested on two tasks: identifying chord types (Task 1), and identifying a single note within a chord (Task 2). A main effect of RP on Task 1 and an interaction between AP and RP in reaction times were found. On Task 2 main effects of AP and RP, and an interaction were found, with highest performance in participants with both high AP and RP. Results suggest that AP and RP should be regarded as two different abilities, and that AP may slow down reaction times for tasks requiring global processing. PMID:24855499

Ziv, Naomi; Radin, Shulamit

2014-01-01

405

Absolute Quantification of Individual Biomass Concentrations in a Methanogenic Coculture  

PubMed Central

Identification of individual biomass concentrations is a crucial step towards an improved understanding of anaerobic digestion processes and mixed microbial conversions in general. The knowledge of individual biomass concentrations allows for the calculation of biomass specific conversion rates which form the basis of anaerobic digestion models. Only few attempts addressed the absolute quantification of individual biomass concentrations in methanogenic microbial ecosystems which has so far impaired the calculation of biomass specific conversion rates and thus model validation. This study proposes a quantitative PCR (qPCR) approach for the direct determination of individual biomass concentrations in methanogenic microbial associations by correlating the native qPCR signal (cycle threshold, Ct) to individual biomass concentrations (mg dry matter/L). Unlike existing methods, the proposed approach circumvents error-prone conversion factors that are typically used to convert gene copy numbers or cell concentrations into actual biomass concentrations. The newly developed method was assessed and deemed suitable for the determination of individual biomass concentrations in a defined coculture of Desulfovibrio sp. G11 and Methanospirillum hungatei JF1. The obtained calibration curves showed high accuracy, indicating that the new approach is well suited for any engineering applications where the knowledge of individual biomass concentrations is required. PMID:24949269

2014-01-01

406

A high-precision mechanical absolute-rotation sensor  

E-print Network

We have developed a mechanical absolute-rotation sensor capable of resolving ground rotation angle of less than 1 nrad$/\\sqrt{\\text{Hz}}$ above $30$ mHz and 0.2 nrad$/\\sqrt{\\text{Hz}}$ above $100$ mHz about a single horizontal axis. The device consists of a meter-scale beam balance, suspended by a pair of flexures, with a resonance frequency of 10.8 mHz. The center of mass is located 3 $\\mu$m above the pivot, giving an excellent horizontal displacement rejection of better than $3\\times10^{-5}$ rad/m. The angle of the beam is read out optically using a high-sensitivity autocollimator. We have also built a tiltmeter with better than 1 nrad$/\\sqrt{\\text{Hz}}$ sensitivity above 30 mHz. Co-located measurements using the two instruments allowed us to distinguish between background rotation signal at low frequencies and intrinsic instrument noise. The rotation sensor is useful for rotational seismology and for rejecting background rotation signal from seismometers in experiments demanding high levels of seismic isol...

Venkateswara, Krishna; Turner, Matthew D; Arp, Trevor; Gundlach, Jens H

2014-01-01

407

On the calculation of absolute macromolecular binding free energies  

PubMed Central

The standard framework for calculating the absolute binding free energy of a macromolecular association reaction A + B ? AB with an association constant KAB is to equate chemical potentials of the species on the left- and right-hand sides of this reaction and evaluate the chemical potentials from theory. This theory involves (usually hidden) assumptions about what constitutes the bound species, AB, and where the contribution of the solvent appears. We present here an alternative derivation that can be traced back to Bjerrum, in which the expectation value of KAB is obtained directly through the statistical mechanical method of evaluating its ensemble (Boltzmann-weighted) average. The generalized Bjerrum approach more clearly delineates: (i) the different contributions to binding; (ii) the origin of the much-discussed and somewhat controversial association entropy term; and (iii) where the solvent contribution appears. This approach also allows approximations required for practical evaluation of the binding constant in complex macromolecular systems, to be introduced in a well defined way. We provide an example, with application to test cases that illustrate a range of binding behavior. PMID:12149474

Luo, Hengbin; Sharp, Kim

2002-01-01

408

Supercontinent Succession and the Calculation of Absolute Paleolongitude  

NASA Astrophysics Data System (ADS)

Where will the next supercontinent form? Traditional ‘introversion’ and ‘extraversion’ models of supercontinent succession predict that Super Asia will respectively form whence Pangea was or on the opposite side of the world. We develop the ‘orthoversion’ model whereby a succeeding supercontinent forms 90° away: somewhere along the great circle of subduction encircling its relict predecessor—a mantle topology that arises when supercontinents develop return flow beneath their mature centroids. This centroid defines the minimum moment of inertia (I_min) about which rapid and oscillatory true polar wander occurs owing to the prolate shape of nonhydrostatic Earth. Fitting great circles to each supercontinent’s true polar wander legacy, we determine that the distances between successive supercontinent centers (I_min axes) are 88° and 87° for Nuna?Rodinia and Rodinia?Pangea, respectively—both as predicted by the orthoversion model. Not only can supercontinent centers be pinned back into Precambrian time, they provide fixed points for the calculation of absolute paleolongitude.

Mitchell, R. N.; Kilian, T.; Evans, D. A.

2010-12-01

409

A high-precision mechanical absolute-rotation sensor.  

PubMed

We have developed a mechanical absolute-rotation sensor capable of resolving ground rotation angle of less than 1 nrad/?Hz above 30 mHz and 0.2 nrad/?Hz above 100 mHz about a single horizontal axis. The device consists of a meter-scale beam balance, suspended by a pair of flexures, with a resonance frequency of 10.8 mHz. The center of mass is located 3 ?m above the pivot, giving an excellent horizontal displacement rejection of better than 3 × 10(-5) rad/m. The angle of the beam is read out optically using a high-sensitivity autocollimator. We have also built a tiltmeter with better than 1 nrad/?Hz sensitivity above 30 mHz. Co-located measurements using the two instruments allowed us to distinguish between background rotation signal at low frequencies and intrinsic instrument noise. The rotation sensor is useful for rotational seismology and for rejecting background rotation signal from seismometers in experiments demanding high levels of seismic isolation, such as Advanced Laser Interferometer Gravitational-wave Observatory. PMID:24517804

Venkateswara, Krishna; Hagedorn, Charles A; Turner, Matthew D; Arp, Trevor; Gundlach, Jens H

2014-01-01

410

Absolute Quantification of the Glycolytic Pathway in Yeast:  

PubMed Central

The availability of label-free data derived from yeast cells (based on the summed intensity of the three strongest, isoform-specific peptides) permitted a preliminary assessment of protein abundances for glycolytic proteins. Following this analysis, we demonstrate successful application of the QconCAT technology, which uses recombinant DNA techniques to generate artificial concatamers of large numbers of internal standard peptides, to the quantification of enzymes of the glycolysis pathway in the yeast Saccharomyces cerevisiae. A QconCAT of 88 kDa (59 tryptic peptides) corresponding to 27 isoenzymes was designed and built to encode two or three analyte peptides per protein, and after stable isotope labeling of the standard in vivo, protein levels were determined by LC-MS, using ultra high performance liquid chromatography-coupled mass spectrometry. We were able to determine absolute protein concentrations between 14,000 and 10 million molecules/cell. Issues such as efficiency of extraction and completeness of proteolysis are addressed, as well as generic factors such as optimal quantotypic peptide selection and expression. In addition, the same proteins were quantified by intensity-based label-free analysis, and both sets of data were compared with other quantification methods. PMID:21931151

Carroll, Kathleen M.; Simpson, Deborah M.; Eyers, Claire E.; Knight, Christopher G.; Brownridge, Philip; Dunn, Warwick B.; Winder, Catherine L.; Lanthaler, Karin; Pir, P?nar; Malys, Naglis; Kell, Douglas B.; Oliver, Stephen G.; Gaskell, Simon J.; Beynon, Robert J.

2011-01-01

411

Computational methodology for absolute calibration curves for microfluidic optical analyses.  

PubMed

Optical fluorescence and absorption are two of the primary techniques used for analytical microfluidics. We provide a thorough yet tractable method for computing the performance of diverse optical micro-analytical systems. Sample sizes range from nano- to many micro-liters and concentrations from nano- to milli-molar. Equations are provided to trace quantitatively the flow of the fundamental entities, namely photons and electrons, and the conversion of energy from the source, through optical components, samples and spectral-selective components, to the detectors and beyond. The equations permit facile computations of calibration curves that relate the concentrations or numbers of molecules measured to the absolute signals from the system. This methodology provides the basis for both detailed understanding and improved design of microfluidic optical analytical systems. It saves prototype turn-around time, and is much simpler and faster to use than ray tracing programs. Over two thousand spreadsheet computations were performed during this study. We found that some design variations produce higher signal levels and, for constant noise levels, lower minimum detection limits. Improvements of more than a factor of 1,000 were realized. PMID:22163573

Chang, Chia-Pin; Nagel, David J; Zaghloul, Mona E

2010-01-01

412

Cosmic backgrounds of relic gravitons and their absolute normalization  

E-print Network

Provided the consistency relations are not violated, the recent Bicep2 observations pin down the absolute normalization, the spectral slope and the maximal frequency of the cosmic graviton background produced during inflation. The properly normalized spectra are hereby computed from the lowest frequencies (of the order of the present Hubble rate) up to the highest frequency range in the GHz region. Deviations from the conventional paradigm cannot be excluded and are examined by allowing for different physical possibilities including, in particular, a running of the tensor spectral index, an explicit breaking of the consistency relations and a spike in the high-frequency tail of the spectrum coming either from a post-inflationary phase dominated by a stiff fluid of from the contribution of waterfall fields in a hybrid inflationary context. The direct determinations of the tensor to scalar ratio at low frequencies, if confirmed by the forthcoming observations, will also affect and constrain the high-frequencies uncertainties. The limits on the cosmic graviton backgrounds coming from wide-band interferometers (such as Ligo/Virgo, Lisa and Bbo/Decigo) together with a more accurate scrutiny of the tensor B mode polarization at low frequencies will set direct bounds on the post-inflationary evolution and on other unconventional completions of the standard lore.

Massimo Giovannini

2014-05-24

413

Cosmic backgrounds of relic gravitons and their absolute normalization  

NASA Astrophysics Data System (ADS)

Provided the consistency relations are not violated, the recent BICEP2 observations pin down the absolute normalization, the spectral slope and the maximal frequency of the cosmic graviton background produced during inflation. The properly normalized spectra are hereby computed from the lowest frequencies (of the order of the present Hubble rate) up to the highest frequency range in the GHz region. Deviations from the conventional paradigm cannot be excluded and are examined by allowing for different physical possibilities including, in particular, a running of the tensor spectral index, an explicit breaking of the consistency relations and a spike in the high-frequency tail of the spectrum coming either from a post-inflationary phase dominated by a stiff fluid or from the contribution of waterfall fields in a hybrid inflationary context. The direct determinations of the tensor to scalar ratio at low frequencies, if confirmed by the forthcoming observations, will also affect and constrain the high-frequency uncertainties. The limits on the cosmic graviton backgrounds coming from wide-band interferometers (such as LIGO/Virgo, LISA and BBO/DECIGO) together with a more accurate scrutiny of the tensor B-mode polarization at low frequencies will set direct bounds on the post-inflationary evolution and on other unconventional completions of the standard lore.

Giovannini, Massimo

2014-11-01

414

Absolute Magnitudes of Dwarf Novae: Murmurs of Period Bounce  

E-print Network

We redetermine the relationship between absolute magnitude and orbital period for dwarf novae, based on 46 stars with good or excellent distance estimates. This improves upon Warner's previous relation, building upon today's improved estimates of distance and binary inclination, and greater wavelength coverage. This calibration is then applied to a set of 210 known or likely dwarf novae, to study the dependence of quiescent M_v, and time-averaged M_v, on orbital period. The resultant M_v(P_orb) curves appear to establish the existence of a lower branch of cataclysmic-variable evolution, resembling the previously known q(P_orb) relation. Stars on the lower branch seem to have the expected properties of "period bouncers" -- with a feeble secondary, faint accretion light, cool white dwarf, and long recurrence time between eruptions. They may also have higher velocities, consistent with a greater age. Some are very nearby, despite strong selection effects discriminating against the discovery of these faint stars ...

Patterson, Joseph

2009-01-01

415

Interpretation of the Arcade 2 Absolute Sky Brightness Measurement  

NASA Technical Reports Server (NTRS)

We use absolutely calibrated data between 3 and 90 GHz from the 2006 balloon flight of the ARCADE 2 instrument, along with previous measurements at other frequencies to constrain models of extragalactic emission. Such emission is a combination of the cosmic microwave background (CMB) monopole, Galactic foreground emission, the integrated contribution of radio emission from external galaxies, any spectral distortions present in the CMB, and any other extragalactic source. After removal of estimates of foreground emission from our own Galaxy, and an estimated contribution of external galaxies, we present fits to a combination of the flat-spectrum CMB and potential spectral distortions in the CMB. We find 217 upper limits to CMB spectral distortions of u < 6x10(exp -4) and [Y(sub ff)] < 1x10(exp -4). We also find a significant detection of a residual signal beyond that, which can be explained by the CMB plus the integrated radio emission from galaxies estimated from existing surveys. This residual signal may be due to an underestimated galactic foreground contribution, an unaccounted for contribution of a background of radio sources, or some combination of both. The residual signal is consistent with emission in the form of a power law with amplitUde 18.4 +/- 2.1 K at 0.31 GHz and a spectral index of -2.57 +/- 0.05.

Seiffert, M.; Fixsen, D. J.; Kogut, A.; Levin, S. M.; Limon, M.; Lubin, P. M.; Mirel, P.; Singal, J.; Villela, T.; Wollack, E.; Wuensche, C. A.

2011-01-01

416

An Absolute Phase Space for the Physicality of Matter  

SciTech Connect

We define an abstract and absolute phase space (''APS'') for sub-quantum intrinsic wave states, in three axes, each mapping directly to a duality having fundamental ontological basis. Many aspects of quantum physics emerge from the interaction algebra and a model deduced from principles of 'unique solvability' and 'identifiable entity', and we reconstruct previously abstract fundamental principles and phenomena from these new foundations. The physical model defines bosons as virtual continuous waves pairs in the APS, and fermions as real self-quantizing snapshots of those waves when simple conditions are met. The abstraction and physical model define a template for the constitution of all fermions, a template for all the standard fundamental bosons and their local interactions, in a common framework and compactified phase space for all forms of real matter and virtual vacuum energy, and a distinct algebra for observables and unobservables. To illustrate our scheme's potential, we provide examples of slit experiment variations (where the model finds theoretical basis for interference only occurring between two final sources), QCD (where we may model most attributes known to QCD, and a new view on entanglement), and we suggest approaches for other varied applications. We believe this is a viable candidate for further exploration as a foundational proposition for physics.

Valentine, John S.

2010-12-22

417

Absolute quantum photoyield of ion damaged diamond surfaces  

NASA Astrophysics Data System (ADS)

We report on the absolute quantum photoyield (QPY) measurements from defective diamond surfaces in the 140-200 nm spectral range. The effect of defects on the photoemission properties of polycrystalline diamond films is studied by intentionally introducing damage using room temperature 30 keV Xe+ ion bombardment at doses ranging from 2×1013 to 2×1015ions/cm2. Ion bombardment results in a drastic degradation of the QPY, to less than 1% at 140 nm, even at the lowest implantation dose, compared to ˜11.5% measured for the unimplanted diamond film. The decrease in QPY is associated with a change of the electron affinity from negative to positive as determined by secondary electron emission measurements. Microwave hydrogen plasma treatment of the damaged diamond films results in complete regeneration of the photoemission properties for diamond films implanted to Xe+ doses up to 2×1014 ions/cm2; however, only partial recovery is obtained for films irradiated with higher ion dose.

Laikhtman, A.; Hoffman, A.; Kalish, R.; Breskin, A.; Chechik, R.

2000-09-01

418

Absolute pitch exhibits phenotypic and genetic overlap with synesthesia.  

PubMed

Absolute pitch (AP) and synesthesia are two uncommon cognitive traits that reflect increased neuronal connectivity and have been anecdotally reported to occur together in an individual. Here we systematically evaluate the occurrence of synesthesia in a population of 768 subjects with documented AP. Out of these 768 subjects, 151 (20.1%) reported synesthesia, most commonly with color. These self-reports of synesthesia were validated in a subset of 21 study subjects, using an established methodology. We further carried out combined linkage analysis of 53 multiplex families with AP and 36 multiplex families with synesthesia. We observed a peak NPL LOD = 4.68 on chromosome 6q, as well as evidence of linkage on chromosome 2, using a dominant model. These data establish the close phenotypic and genetic relationship between AP and synesthesia. The chromosome 6 linkage region contains 73 genes; several leading candidate genes involved in neurodevelopment were investigated by exon resequencing. However, further studies will be required to definitively establish the identity of the causative gene(s) in the region. PMID:23406871

Gregersen, Peter K; Kowalsky, Elena; Lee, Annette; Baron-Cohen, Simon; Fisher, Simon E; Asher, Julian E; Ballard, David; Freudenberg, Jan; Li, Wentian

2013-05-15

419

Absolute configuration of vouaca-pen-5?-ol  

PubMed Central

The title compound, C20H30O2, {systematic name: (4aR,6aS,7R,11aS,11bR)-4,4,7,11b-tetra­methyl-1,2,3,4,4a,5,6,6a,7,11,11a,11b-dodeca­hydro­phenanthro[3,2-b]furan-4a-ol}, is a cas­sane furan­oditerpene which was isolated from the roots of Caesalpinia pulcherrima. The absolute configurations at positions 4a, 6a, 7, 11a and 11b are R, S, R, S and R, respectively. The mol­ecule has four-fused rings consisting of three cyclo­hexane rings and one furan ring. The three cyclo­hexane rings are trans-fused. Two cyclo­hexane rings are in chair conformations, while the third is in an envelope conformation. In the crystal structure, the mol­ecules are linked by inter­molecular O—H?O hydrogen bonds into a zigzag chain along the a axis. A short O?O contact [3.0398?(14)?Å] is also present. PMID:21588448

Fun, Hoong-Kun; Yodsaoue, Orapun; Chantrapromma, Suchada; Karalai, Chatchanok

2010-01-01

420

Old and new research on the Absolute Parallelism theory  

E-print Network

Compatible equations, Singularities of solutions, Topological charges and quasi-charges. PhD thesis (translated frorm Russian). The book shows the sights of Absolute Parallelism (AP), and contains useful information on the problem of singularities, compatibility theory, homotopy groups (also relative and k-ad), topological quasi-charge groups and their morphisms. AP is a single (frame) field theory proposed by Einstein some 80 years ago; it embraces symmetries of both Special and General Relativity. The compatibility theory, if applied to the cases when the frame matrix degenerates, gives a covariant test on singularities of solutions. This gives a single variant (missed in Einstein-Mayer's list of compatible equations), the unique 5D equation (nothing, nor D, can be changed), which solutions are free of emerging singularities. SO4-symmetrical nonstationary solutions give rise to a cosmological model (relativistic surfing; anti-Milne model in FRW framework) with a specific reduction of the extra-dimension. Topological classification of localized field configurations, combinatorics of topological quasi-charges (quanta), is discussed in an attempt to imagine the Standard Model (and quantum theory itself; and, perhaps, to make some qualitative predictions, like the absence of spin zero elementary quanta).

I. L. Zhogin

2004-12-31

421

Absolute paleointensity from Hawaiian lavas younger than 35 ka  

USGS Publications Warehouse

Paleointensity studies have been conducted in air and in argon atmosphere on nine lava flows with radiocarbon ages distributed between 3.3 and 28.2 ka from the Mauna Loa volcano in the big island of Hawaii. Determinations of paleointensity obtained at eight sites depict the same overall pattern as the previous results for the same period in Hawaii, although the overall average field intensity appears to be lower. Since the present results were determined at higher temperatures than in the previous studies, this discrepancy raises questions regarding the selection of low versus high-temperature segments that are usually made for absolute paleointensity. The virtual dipole moments are similar to those displayed by the worldwide data set obtained from dated lava flows. When averaged within finite time intervals, the worldwide values match nicely the variations of the Sint-200 synthetic record of relative paleointensity and confirm the overall decrease of the dipole field intensity during most of this period. The convergence between the existing records at Hawaii and the rest of the world does not favour the presence of persistent strong non-dipole components beneath Hawaii for this period.

Valet, J.-P.; Tric, E.; Herrero-Bervera, E.; Meynadier, L.; Lockwood, J.P.

1998-01-01

422

Acceleration statistics in thermally driven superfluid turbulence  

NASA Astrophysics Data System (ADS)

New methods of flow visualization near absolute zero have opened the way to directly compare quantum turbulence (in superfluid helium) to classical turbulence (in ordinary fluids such as air or water) and explore analogies and differences. We present results of numerical simulations in which we examine the statistics of the superfluid acceleration in thermal counterflow. We find that, unlike the velocity, the acceleration obeys scaling laws similar to classical turbulence, in agreement with a recent quantum turbulence experiment of La Mantia et al.

Baggaley, Andrew W.; Barenghi, Carlo F.

2014-03-01

423

Documentation for the machine-readable version of the Absolute Calibration of Stellar Spectrophotometry  

NASA Technical Reports Server (NTRS)

The machine-readable data file of The Absolute Calibration of Stellar Spectrophotometry as distributed by the Astronomical Data Center is described. The data file contains the absolute fluxes for 16 stars published in Tables 1 and 2 of Johnson (1980). The absolute calibrations were accomplished by combining the 13-color photometry calibrations of Johnson and Mitchell (1975) with spectra obtained with a Michelson spectrophotometer and covering the wavelength range 4000 to 10300 A (Johnson 1977). The agreement between this absolute calibration and another recent one based upon data for a Lyr and 109 Vir by Tug, White and Lockwood (1977) is shown by Johnson (1980) to be quite good.

Warren, W. H., Jr.

1982-01-01

424

Observational constraints on atmospheric radiaitve feedbacks: absolute accuracy and next-generation observing systems  

NASA Astrophysics Data System (ADS)

The central role of atmospheric radiative feedbacks to understanding and projecting climate change calls for a robust observational system. Recent studies have shown the value of space-based measurements for putting quantitative constraints on a range of radiative feedback processes through a fingerprinting method applied to long-term observational records. More recent work has suggested the value of demonstrably accurate measurements to disentangle model error from observational uncertainties within reanalysis systems, potentially yielding improved representations of feedback processes within just a few years. Both of these methods rely on space-based measurements that can be objectively tested for accuracy on-orbit. A new class of mission has been proposed that incorporates the same type of empirical tests for accuracy as used in the laboratory into a space-based sensor. One example of such a mission is the Climate Absolute Radiance and Refractivity Observatory (CLARREO), a new mission suggested by the 2006 National Research Council Decadal Survey. CLARREO includes three sensor types: thermal infrared, microwave, and reflected shortwave. This paper presents a laboratory demonstration of prototype systems for testing the on-orbit accuracy of a thermal infrared sensor for CLARREO. These systems utilize infrared lasers to provide monochromatic light sources to quantitatively determine the optical properties of materials. These infrared optical properties are major determinants of the on-orbit radiometric performance of a thermal infrared sensor. For this reason, reliable quantitative information (including uncertainty) that tracks any changes in relevant infrared materials over the mission lifetime is essential to objective assessment of instrument accuracy. The practicality of mid-infrared lasers for these applications is due to the availability and continued evolution of compact, high-efficiency Quantum Cascade Lasers (QCLs). These lasers can provide over 100 mW of continuous wave (cw) monochromatic illumination at room temperature. In this paper, results are presented on recent QCL technological advances and environmental qualification. The results of QCL-based systems for testing optical materials, specifically the reflectance of calibration standards, are analyzed and compared with laboratory techniques. The results of the spectral calibration of sensors by utilizing the monochromatic property of QCL illumination will also be shown.

Dykema, J. A.; Hanssen, L. M.; Mekhontsev, S.; Anderson, J.

2012-12-01

425

Preliminary OARE absolute acceleration measurements on STS-50  

NASA Technical Reports Server (NTRS)

On-orbit Orbital Acceleration Research Experiment (OARE) data on STS-50 was examined in detail during a 2-day time period. Absolute acceleration levels were derived at the OARE location, the orbiter center-of-gravity, and at the STS-50 spacelab Crystal Growth Facility. The tri-axial OARE raw acceleration measurements (i.e., telemetered data) during the interval were filtered using a sliding trimmed mean filter in order to remove large acceleration spikes (e.g., thrusters) and reduce the noise. Twelve OARE measured biases in each acceleration channel during the 2-day interval were analyzed and applied to the filtered data. Similarly, the in situ measured x-axis scale factors in the sensor's most sensitive range were also analyzed and applied to the data. Due to equipment problem(s) on this flight, both y- and z- axis sensitive range scale factors were determined in a separate process (using the OARE maneuver data) and subsequently applied to the data. All known significant low-frequency corrections at the OARE location (i.e., both vertical and horizontal gravity-gradient, and rotational effects) were removed from the filtered data in order to produce the acceleration components at the orbiter's center-of-gravity, which are the aerodynamic signals along each body axes. Results indicate that there is a force of unknown origin being applied to the Orbiter in addition to the aerodynamic forces. The OARE instrument and all known gravitational and electromagnetic forces were reexamined, but none produce the observed effect. Thus, it is tentatively concluded that the Orbiter is creating the environment observed.

Blanchard, Robert C.; Nicholson, John Y.; Ritter, James

1993-01-01

426

a Portable Apparatus for Absolute Measurements of the Earth's Gravity.  

NASA Astrophysics Data System (ADS)

We have developed a new, portable apparatus for making absolute measurements of the acceleration due to the earth's gravity. We use the method of interferometrically determining the acceleration of a freely falling corner -cube prism. The falling object is surrounded by a chamber which is driven vertically inside a fixed vacuum chamber. This falling chamber is servoed to track the falling corner -cube to shield it from drag due to background gas. In addition, the drag-free falling chamber removes the need for a magnetic release, shields the falling object from electrostatic forces, and provides a means of both gently arresting the falling object and quickly returning it to its start position, to allow rapid acquisition of data. A synthesized long period isolation device reduces the noise due to seismic oscillations. A new type of Zeeman laser is used as the light source in the interferometer, and is compared with the wavelength of an iodine stabilized laser. The times of occurrence of 45 interference fringes are measured to within 0.2 nsec over a 20 cm drop and are fit to a quadratic by an on-line minicomputer. 150 drops can be made in ten minutes resulting in a value of g having a precision of 3 to 6 parts in 10('9). Systematic errors have been determined to be less than 5 parts in 10('9) through extensive tests. Three months of gravity data have been obtained with a reproducibility ranging from 5 to 10 parts in 10('9). The apparatus has been designed to be easily portable. Field measurements are planned for the immediate future. An accuracy of 6 parts in 10('9) corresponds to a height sensitivity of 2 cm. Vertical motions in the earth's crust and tectonic density changes that may precede earthquakes are to be investigated using this apparatus.

Zumberge, Mark Andrew

427

Absolute Timing of the Crab Pulsar with RXTE  

NASA Technical Reports Server (NTRS)

We have monitored the phase of the main X-ray pulse of the Crab pulsar with the Rossi X-ray Timing Explorer (RXTE) for almost eight years, since the start of the mission in January 1996. The absolute time of RXTE's clock is sufficiently accurate to allow this phase to be compared directly with the radio profile. Our monitoring observations of the pulsar took place bi-weekly (during the periods when it was at least 30 degrees from the Sun) and we correlated the data with radio timing ephemerides derived from observations made at Jodrell Bank. We have determined the phase of the X-ray main pulse for each observation with a typical error in the individual data points of 50 microseconds. The total ensemble is consistent with a phase that is constant over the monitoring period, with the X-ray pulse leading the radio pulse by 0.01025 plus or minus 0.00120 period in phase, or 344 plus or minus 40 microseconds in time. The error estimate is dominated by a systematic error of 40 microseconds, most likely constant, arising from uncertainties in the instrumental calibration of the radio data. The statistical error is 0.00015 period, or 5 microseconds. The separation of the main pulse and interpulse appears to be unchanging at time scales of a year or less, with an average value of 0.4001 plus or minus 0.0002 period. There is no apparent variation in these values with energy over the 2-30 keV range. The lag between the radio and X-ray pulses ma be constant in phase (i.e., rotational in nature) or constant in time (i.e., due to a pathlength difference). We are not (yet) able to distinguish between these two interpretations.

Rots, Arnold H.; Jahoda, Keith; Lyne, Andrew G.

2004-01-01

428

An Absolute Radius Scale for Saturn's Rings from Cassini Occultations  

NASA Astrophysics Data System (ADS)

Abstract (2,250 Maximum Characters): The Cassini mission has provided a remarkable opportunity to investigate the structure and dynamics of the Saturn ring system at the sub-km radial scale, using hundreds of individual stellar and radio occultations from the UVIS, VIMS, and RSS instruments. From precise measurements of ring and gap edges, we have been able to determine the orbital characteristics of over one hundred features in the rings. A crucial step in the orbital determination is the establishment of a highly accurate radius scale for the rings. This is compounded by uncertainties in the positions of the occulted stars, km-scale trajectory errors in the spacecraft location, and inexact knowledge of the direction and precession rate of Saturn’s pole. We have taken an iterative approach in which we identify a set of 30 or so putative circular, equatorial features, solve for along-track trajectory errors for each occultation, and use this best-fitting orbital solution to establish the reference system for determination of the orbits of non-circular ring features. Using thousands of individual measurements of rings in the Cassini data, we have determined an absolute radius scale for each contributing occultation with an accuracy of about 200 m for the C and B rings and the Cassini Division. This enables us to detect and measure very small dynamical effects such as weak normal modes in ring edges, and to determine the phases of density waves, including very short wavelength outer Lindblad resonances in the C ring, as reported at this meeting. We calculate the sensitivity of the radius scale to the assumed pole direction and precession rate. Ultimately, we will combine these results with Voyager, HST, and pre-Cassini Earth-based occultation measurements to refine our knowledge of Saturn’s pole direction and precession.

McGhee, Colleen; French, R. G.; Jacobson, R. A.; Nicholson, P. D.; Colwell, J. E.; Marouf, E. A.; Lonergan, K.; Sepersky, T.

2013-05-01

429

Redetermination and absolute configuration of pruniflorone M monohydrate  

PubMed Central

The title xanthone known as pruniflorone M (systematic name: (2R)-5,10-dihy­droxy-2-hy­droxy­methyl-1,1-dimethyl-1H-furo[2,3-c]xanthen-6-one), crystallized in a monohydrate form, C18H16O6·H2O. It was isolated from the green fruits of Cratoxylum formosum ssp. pruniflorum. The structure of the title compound has been reported previously [Boonnak et al. (2010 ?). Aust. J. Chem. 63, 1550–1556], but we report here the absolute configuration determined using Cu K? radiation. There are two crystallograpically independent mol­ecules in the asymmetric unit, which differ slightly in the bond angles. The hy­droxy­methyl substituents at position 2 of the furan rings of both pruniflorone M mol­ecules adopt R configurations. In both mol­ecules, the three rings of the xanthone skeleton are approximately coplanar, with an r.m.s. deviation of 0.0124?(2)?Å for one mol­ecule and 0.0289?(2)?Å for the other, and the furan ring adopts an envelope conformation. In the crystal, mol­ecules of pruniflorone M and water are linked into a two-dimensional network by O—H?O hydrogen bonds and weak C—H?O inter­actions. The crystal structure is further consolidated by ?–? inter­actions with centroid–centroid distances in the range 3.5987?(13)–3.7498?(14)?Å. Short C?C [3.378?(3)?Å] and O?O [2.918?(3)?Å] contacts are also observed. PMID:22090964

Fun, Hoong-Kun; Chantrapromma, Suchada; Boonnak, Nawong; Karalai, Chatchanok; Chantrapromma, Kan

2011-01-01

430

PHASES: A Project to Perform Absolute Spectrophotometry from Space  

NASA Astrophysics Data System (ADS)

This paper presents the current status of the opto-mechanical design of PHASES (Planet Hunting and AsteroSeismology Explorer Spectrophotometer), which is a project to develop a space-borne telescope to obtain absolute flux calibrated spectra of bright stars. The science payload is intended to be housed in a micro-satellite launched into a low-earth Sun-synchronous orbit with an inclination to the equator of 98.7° and a local time ascending node LTAN of 6:00 AM. PHASES will be able to measure micromagnitude photometric variations due to stellar oscillations/activity and planet/moon transits. It consists of a 20 cm aperture modified Baker telescope feeding two detectors: the tracking detector provides the fine telescope guidance system with a required pointing stability of 0.2?, and the science detector performs spectrophotometry in the wavelength range 370-960 nm with a resolving power between 200 and 900. The spectrograph is designed to provide 1% RMS flux calibrated spectra with signal-to-noise ratios > 100 for stars with V < 10 in short integration times. Our strategy to calibrate the system using A type stars is explained. From comparison with model atmospheres it would be possible to determine the stellar angular diameters with an uncertainty of approximately 0.5%. In the case of a star hosting a transiting planet it would be possible to derive its light curve, and then the planet to stellar radius ratio. Bright stars have high precision Hipparcos parallaxes and the expected level of accuracy for their fluxes will be propagated to the stellar radii, and more significantly to the planetary radii. The scientific drivers for PHASES give rise to some design challenges, which are particularly related to the opto-mechanics for extreme environmental conditions. The optical design has been developed with the primary goal of avoiding stray light reaching the science detector. Three different proposals for the opto-mechanical design are under investigation.

del Burgo, C.; Vather, D.; Allende Prieto, C.; Murphy, N.

2013-04-01

431

Embedded north-seeker for automatic absolute magnetic DI measurements  

NASA Astrophysics Data System (ADS)

In magnetic observatory Earth magnetic field is recorded with a resolution of 0.1nT for 1min sampling (new standards impose 1pT for 1s sampling). The method universally adopted for measuring it is a combination of three instruments. Vectorial magnetometer (variometer) records variations of the three components around a reference value or a baseline. A proton or an overhauser magnetometer is an absolute instrument able to measure the modulus of the field and used to determine the F component baseline of the variometer. The declination and inclination baselines require a manual procedure to be computed. An operator manipulates a non-magnetic theodolite (also called a DIFlux) to measure the D and I angles in different configurations with a resolution of a few arcsec. The AutoDIF is a non-magnetic automatic DIFlux using the same protocol as the manual procedure. The declination defined according to the true north is determined by means of a target pointing system. Even if the technique is fast and accurate, it becomes problematic in case of unmanned deployment. In particular the area between the target and the DIFlux is out of control. Snow storm, fog, vegetation or condensation on windows are examples of perturbation preventing for finding the target. It is obvious in case of (future) seafloor observatories. A FOG based north-seeker has been implemented and mounted on the AutoDIF. The first results using a low cost gyro don't meet the Intermagnet specifications yet but are however hopeful. A 0.1° standard deviation has been reached and statistically reduced to 0.01° after less than two days in laboratory. The magnetic disturbance of the sensor is taken into account and compensated by the measurement protocol.

Gonsette, Alexandre; Rasson, Jean

2014-05-01

432

New experimental methodology, setup and LabView program for accurate absolute thermoelectric power and electrical resistivity measurements between 25 and 1600 K: Application to pure copper, platinum, tungsten, and nickel at very high temperatures  

NASA Astrophysics Data System (ADS)

In this paper we describe an experimental setup designed to measure simultaneously and very accurately the resistivity and the absolute thermoelectric power, also called absolute thermopower or absolute Seebeck coefficient, of solid and liquid conductors/semiconductors over a wide range of temperatures (room temperature to 1600 K in present work). A careful analysis of the existing experimental data allowed us to extend the absolute thermoelectric power scale of platinum to the range 0-1800 K with two new polynomial expressions. The experimental device is controlled by a LabView program. A detailed description of the accurate dynamic measurement methodology is given in this paper. We measure the absolute thermoelectric power and the electrical resistivity and deduce with a good accuracy the thermal conductivity using the relations between the three electronic transport coefficients, going beyond the classical Wiedemann-Franz law. We use this experimental setup and methodology to give new very accurate results for pure copper, platinum, and nickel especially at very high temperatures. But resistivity and absolute thermopower measurement can be more than an objective in itself. Resistivity characterizes the bulk of a material while absolute thermoelectric power characterizes the material at the point where the electrical contact is established with a couple of metallic elements (forming a thermocouple). In a forthcoming paper we will show that the measurement of resistivity and absolute thermoelectric power characterizes advantageously the (change of) phase, probably as well as DSC (if not better), since the change of phases can be easily followed during several hours/days at constant temperature.

Abadlia, L.; Gasser, F.; Khalouk, K.; Mayoufi, M.; Gasser, J. G.

2014-09-01

433

New experimental methodology, setup and LabView program for accurate absolute thermoelectric power and electrical resistivity measurements between 25 and 1600 K: Application to pure copper, platinum, tungsten, and nickel at very high temperatures.  

PubMed

In this paper we describe an experimental setup designed to measure simultaneously and very accurately the resistivity and the absolute thermoelectric power, also called absolute thermopower or absolute Seebeck coefficient, of solid and liquid conductors/semiconductors over a wide range of temperatures (room temperature to 1600 K in present work). A careful analysis of the existing experimental data allowed us to extend the absolute thermoelectric power scale of platinum to the range 0-1800 K with two new polynomial expressions. The experimental device is controlled by a LabView program. A detailed description of the accurate dynamic measurement methodology is given in this paper. We measure the absolute thermoelectric power and the electrical resistivity and deduce with a good accuracy the thermal conductivity using the relations between the three electronic transport coefficients, going beyond the classical Wiedemann-Franz law. We use this experimental setup and methodology to give new very accurate results for pure copper, platinum, and nickel especially at very high temperatures. But resistivity and absolute thermopower measurement can be more than an objective in itself. Resistivity characterizes the bulk of a material while absolute thermoelectric power characterizes the material at the point where the electrical contact is established with a couple of metallic elements (forming a thermocouple). In a forthcoming paper we will show that the measurement of resistivity and absolute thermoelectric power characterizes advantageously the (change of) phase, probably as well as DSC (if not better), since the change of phases can be easily followed during several hours/days at constant temperature. PMID:25273786

Abadlia, L; Gasser, F; Khalouk, K; Mayoufi, M; Gasser, J G

2014-09-01

434

Thermal diffusivity sensing: A new temperature sensing paradigm  

Microsoft Academic Search

This paper presents an overview of recently developed absolute temperature sensors based on the measurement of the thermal diffusivity of silicon, D. Such sensors make use of the fact that, in IC-grade silicon, D has a well-defined temperature dependence and is insensitive to process spread. D can be determined by measuring the thermal delay between an on-chip heater and an

C. P. L. van Vroonhoven; K. A. A. Makinwa

2011-01-01

435

Thermal conductivity of liquid InSb and liquid Ga.  

NASA Technical Reports Server (NTRS)

The mean thermal conductivity of liquid gallium was measured as 70 (plus or minus 7) W/m/K over the range 250-550 C. For indium antimonide, Kl = 2.04Ks at the melting temperature with Kl = 9.23 W/m/K- as a reasonable absolute value.

Seidensticker, R. G.; Rubenstein, M.

1972-01-01

436

A general variational principle for thermal insulation system design  

Microsoft Academic Search

The paper proposes a conceptually new method for thermal insulation system optimization. The method, based on minimizing thermodynamic irreversibility, consists of externally controlling the variation of heat leak with temperature across the insulation. It is demonstrated that the useful power savings registered from applying this design philosophy are important. Prime candidates for this method are insulation systems facing high absolute

Adrian Bejan

1979-01-01

437

The Functional Significance of Absolute Power with Respect to Event-Related Desynchronization  

Microsoft Academic Search

The question is examined whether the extent of changes in relative band power as measured by event-related desynchronization (ERD) depends on absolute band power. The results for target stimuli of a simple oddball task indicate that the prestimulus (reference) level of absolute band power has indeed a strong influence on ERD. Whereas for the alpha band large band power in

Michael M. Doppelmayr; Wolfgang Klimesch; Thomas Pachinger; Barbara Ripper

1998-01-01

438

Free volume hypothetical scanning molecular dynamics method for the absolute free energy of liquids  

E-print Network

Free volume hypothetical scanning molecular dynamics method for the absolute free energy of liquids for calculating the absolute entropy, S, and free energy, F, by analyzing Boltzmann samples obtained by Monte. In this paper we remove the excluded volume EV restriction, replacing it by a "free volume" FV approach

Meirovitch, Hagai

439

Research on Absolute Positioning System for High-speed Maglev Train  

Microsoft Academic Search

In the high-speed Maglev system, accurate real time information of the train position is essential for stable, safe and efficient train operation. To detect the absolute location of the Maglev train, a detection scheme was proposed based on electromagnetic induction theory. In this scheme, the absolute position of the maglev train was detected by using on-board flag readers to collect

Cunyuan Qian; Zhengzhi Han; Weida Xie

2007-01-01

440

Absolute magnitudes for late-type dwarf stars for Sloan photometry  

E-print Network

We present a new formula for absolute magnitude determination for late-type dwarf stars as a function of (g-r) and (r-i) for Sloan photometry. The absolute magnitudes estimated by this approach are brighter than those estimated by colour-magnitude diagrams, and they reduce the luminosity function rather close to the luminosity function of Hipparcos.

S. Bilir; S. Karaali; S. Tuncel

2005-03-18

441

The Mauna Kea Observatories Near-Infrared Filter Set. III. Isophotal Wavelengths and Absolute Calibration  

E-print Network

The isophotal wavelengths, flux densities, and AB magnitudes for Vega (alpha Lyr) are presented for the Mauna Kea Observatories near-infrared filter set. We show that the near-infrared absolute calibration for Vega determined by Cohen et al. and Megessier are consistent within the uncertainties, so that either absolute calibration may be used.

A. T. Tokunaga; W. D. Vacca

2005-02-05

442

Analysis of Large Flexible Body Deformation in Multibody Systems Using Absolute Coordinates  

Microsoft Academic Search

To consider large deformation problems in multibody system simulations afinite element approach, called absolute nodal coordinate.formulation,has been proposed. In this formulation absolute nodal coordinates andtheir material derivatives are applied to represent both deformation andrigid body motion. The choice of nodal variables allows a fullynonlinear representation of rigid body motion and can provide the exactrigid body inertia in the case of

Stefan von Dombrowski

2002-01-01

443

How the absolute growth rate of poplar adapts to the light-NO-3-dosage  

E-print Network

. A poplar plant adapts its absolute growth rate to high irradiance by a gradually faster pro- duction of the organs and the development of absolute growth rate of the pl