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Sample records for absolute humidity modulates

  1. Absolute Humidity and the Seasonality of Influenza (Invited)

    NASA Astrophysics Data System (ADS)

    Shaman, J. L.; Pitzer, V.; Viboud, C.; Grenfell, B.; Goldstein, E.; Lipsitch, M.

    2010-12-01

    Much of the observed wintertime increase of mortality in temperate regions is attributed to seasonal influenza. A recent re-analysis of laboratory experiments indicates that absolute humidity strongly modulates the airborne survival and transmission of the influenza virus. Here we show that the onset of increased wintertime influenza-related mortality in the United States is associated with anomalously low absolute humidity levels during the prior weeks. We then use an epidemiological model, in which observed absolute humidity conditions temper influenza transmission rates, to successfully simulate the seasonal cycle of observed influenza-related mortality. The model results indicate that direct modulation of influenza transmissibility by absolute humidity alone is sufficient to produce this observed seasonality. These findings provide epidemiological support for the hypothesis that absolute humidity drives seasonal variations of influenza transmission in temperate regions. In addition, we show that variations of the basic and effective reproductive numbers for influenza, caused by seasonal changes in absolute humidity, are consistent with the general timing of pandemic influenza outbreaks observed for 2009 A/H1N1 in temperate regions. Indeed, absolute humidity conditions correctly identify the region of the United States vulnerable to a third, wintertime wave of pandemic influenza. These findings suggest that the timing of pandemic influenza outbreaks is controlled by a combination of absolute humidity conditions, levels of susceptibility and changes in population mixing and contact rates.

  2. The relationship between indoor and outdoor temperature, apparent temperature, relative humidity, and absolute humidity.

    PubMed

    Nguyen, J L; Schwartz, J; Dockery, D W

    2014-02-01

    Many studies report an association between outdoor ambient weather and health. Outdoor conditions may be a poor indicator of personal exposure because people spend most of their time indoors. Few studies have examined how indoor conditions relate to outdoor ambient weather. The average indoor temperature, apparent temperature, relative humidity (RH), and absolute humidity (AH) measured in 16 homes in Greater Boston, Massachusetts, from May 2011 to April 2012 was compared to measurements taken at Boston Logan airport. The relationship between indoor and outdoor temperatures is nonlinear. At warmer outdoor temperatures, there is a strong correlation between indoor and outdoor temperature (Pearson correlation coefficient, r = 0.91, slope, β = 0.41), but at cooler temperatures, the association is weak (r = 0.40, β = 0.04). Results were similar for outdoor apparent temperature. The relationships were linear for RH and AH. The correlation for RH was modest (r = 0.55, β = 0.39). Absolute humidity exhibited the strongest indoor-to-outdoor correlation (r = 0.96, β = 0.69). Indoor and outdoor temperatures correlate well only at warmer outdoor temperatures. Outdoor RH is a poor indicator of indoor RH, while indoor AH has a strong correlation with outdoor AH year-round. PMID:23710826

  3. The relationship between indoor and outdoor temperature, apparent temperature, relative humidity, and absolute humidity

    PubMed Central

    Nguyen, Jennifer L.; Schwartz, Joel; Dockery, Douglas W.

    2013-01-01

    Introduction Many studies report an association between outdoor ambient weather and health. Outdoor conditions may be a poor indicator of personal exposure because people spend most of their time indoors. Few studies have examined how indoor conditions relate to outdoor ambient weather. Methods and Results The average indoor temperature, apparent temperature, relative humidity (RH), and absolute humidity (AH) measured in 16 homes in Greater Boston, Massachusetts, from May 2011 - April 2012 was compared to measurements taken at Boston Logan airport. The relationship between indoor and outdoor temperatures is non-linear. At warmer outdoor temperatures, there is a strong correlation between indoor and outdoor temperature (Pearson correlation coefficient, r = 0.91, slope, β = 0.41), but at cooler temperatures, the association is weak (r = 0.40, β = 0.04). Results were similar for outdoor apparent temperature. The relationships were linear for RH and AH. The correlation for RH was modest (r = 0.55, β = 0.39). AH exhibited the strongest indoor-to-outdoor correlation (r = 0.96, β = 0.69). Conclusions Indoor and outdoor temperatures correlate well only at warmer outdoor temperatures. Outdoor RH is a poor indicator of indoor RH, while indoor AH has a strong correlation with outdoor AH year-round. PMID:23710826

  4. STATISTICAL COMPARISON OF THE EFFECT OF RELATIVE AND ABSOLUTE HUMIDITY ON FIXED-BED CARBON ADSORPTION CAPACITY

    EPA Science Inventory

    The paper describes statistical methods used to evaluate data for toluene (at several typical operating temperatures and humidity levels) and to determine which measure of humidity (relative or absolute) is more important in determining carbon adsorption efficiency. The water con...

  5. Absolute Humidity Influences the Seasonal Persistence and Infectivity of Human Norovirus.

    PubMed

    Colas de la Noue, Alexandre; Estienney, Marie; Aho, Serge; Perrier-Cornet, Jean-Marie; de Rougemont, Alexis; Pothier, Pierre; Gervais, Patrick; Belliot, Gaël

    2014-12-01

    Norovirus (NoV) is one of the main causative agents of acute gastroenteritis worldwide. In temperate climates, outbreaks peak during the winter season. The mechanism by which climatic factors influence the occurrence of NoV outbreaks is unknown. We hypothesized that humidity is linked to NoV seasonality. Human NoV is not cultivatable, so we used cultivatable murine norovirus (MNV) as a surrogate to study its persistence when exposed to various levels of relative humidity (RH) from low (10% RH) to saturated (100% RH) conditions at 9 and 25°C. In addition, we conducted similar experiments with virus-like particles (VLPs) from the predominant GII-4 norovirus and studied changes in binding patterns to A, B, and O group carbohydrates that might reflect capsid alterations. The responses of MNV and VLP to humidity were somewhat similar, with 10 and 100% RH exhibiting a strong conserving effect for both models, whereas 50% RH was detrimental for MNV infectivity and VLP binding capacity. The data analysis suggested that absolute humidity (AH) rather than RH is the critical factor for keeping NoV infectious, with an AH below 0.007 kg water/kg air being favorable to NoV survival. Retrospective surveys of the meteorological data in Paris for the last 14 years showed that AH average values have almost always been below 0.007 kg water/kg air during the winter (i.e., 0.0046 ± 0.0014 kg water/kg air), and this finding supports the fact that low AH provides an ideal condition for NoV persistence and transmission during cold months. PMID:25217015

  6. Absolute Humidity Influences the Seasonal Persistence and Infectivity of Human Norovirus

    PubMed Central

    Colas de la Noue, Alexandre; Estienney, Marie; Aho, Serge; Perrier-Cornet, Jean-Marie; de Rougemont, Alexis; Pothier, Pierre

    2014-01-01

    Norovirus (NoV) is one of the main causative agents of acute gastroenteritis worldwide. In temperate climates, outbreaks peak during the winter season. The mechanism by which climatic factors influence the occurrence of NoV outbreaks is unknown. We hypothesized that humidity is linked to NoV seasonality. Human NoV is not cultivatable, so we used cultivatable murine norovirus (MNV) as a surrogate to study its persistence when exposed to various levels of relative humidity (RH) from low (10% RH) to saturated (100% RH) conditions at 9 and 25°C. In addition, we conducted similar experiments with virus-like particles (VLPs) from the predominant GII-4 norovirus and studied changes in binding patterns to A, B, and O group carbohydrates that might reflect capsid alterations. The responses of MNV and VLP to humidity were somewhat similar, with 10 and 100% RH exhibiting a strong conserving effect for both models, whereas 50% RH was detrimental for MNV infectivity and VLP binding capacity. The data analysis suggested that absolute humidity (AH) rather than RH is the critical factor for keeping NoV infectious, with an AH below 0.007 kg water/kg air being favorable to NoV survival. Retrospective surveys of the meteorological data in Paris for the last 14 years showed that AH average values have almost always been below 0.007 kg water/kg air during the winter (i.e., 0.0046 ± 0.0014 kg water/kg air), and this finding supports the fact that low AH provides an ideal condition for NoV persistence and transmission during cold months. PMID:25217015

  7. Instrument uncertainty effect on calculation of absolute humidity using dewpoint, wet-bulb, and relative humidity sensors

    SciTech Connect

    Slayzak, S.J.; Ryan, J.P.

    1998-04-01

    As part of the US Department of Energy`s Advanced Desiccant Technology Program, the National Renewable Energy Laboratory (NREL) is characterizing the state-of-the-art in desiccant dehumidifiers, the key component of desiccant cooling systems. The experimental data will provide industry and end users with independent performance evaluation and help researchers assess the energy savings potential of the technology. Accurate determination of humidity ratio is critical to this work and an understanding of the capabilities of the available instrumentation is central to its proper application. This paper compares the minimum theoretical random error in humidity ratio calculation for three common measurement methods to give a sense of the relative maximum accuracy possible for each method assuming systematic errors can be made negligible. A series of experiments conducted also illustrate the capabilities of relative humidity sensors as compared to dewpoint sensors in measuring the grain depression of desiccant dehumidifiers. These tests support the results of the uncertainty analysis. At generally available instrument accuracies, uncertainty in calculated humidity ratio for dewpoint sensors is determined to be constant at approximately 2%. Wet-bulb sensors range between 2% and 6% above 10 g/kg (4%--15% below), and relative humidity sensors vary between 4% above 90% rh and 15% at 20% rh. Below 20% rh, uncertainty for rh sensors increases dramatically. Highest currently attainable accuracies bring dewpoint instruments down to 1% uncertainty, wet bulb to a range of 1%--3% above 10 g/kg (1.5%--8% below), and rh sensors between 1% and 5%.

  8. Comparison of absolute and relative air humidity sensors fabricated with inkjet printing technology

    NASA Astrophysics Data System (ADS)

    Selma, R.; Tarapata, G.; Marzecki, M.

    2015-09-01

    This paper describes design, manufacturing and testing of novelty humidity sensors manufactured in inkjet printing technology. Two types of sensors were produced - sensor for dew point hygrometer, along with heater and thermistor, and a relative humidity sensor. Both were tested and proven to be functional, with both advantages and disadvantages described further in the article.

  9. Ocean Temperature and Humidity Sensor Design Based on SHT75 Module

    NASA Astrophysics Data System (ADS)

    Zhao, Jie; Yang, Li; Gai, Zhigang; Yang, Junxian; Yang, Ying

    SHT75 is a temperature and humidity module with high precision, low power consumption, two line output. An intelligent output temperature and humidity sensor is developed based on this module. The hardware and software design are introduced in detail in this paper. In addition, temperature and humidity correction parameters can be calculated by polynomial curve fitting. Experimental results show that the polynomial curve fitting after correction for temperature and humidity sensor can reach to more accurate measurement accuracy.

  10. Absolute negative mobility induced by potential phase modulation

    NASA Astrophysics Data System (ADS)

    Dandogbessi, Bruno S.; Kenfack, Anatole

    2015-12-01

    We investigate the transport properties of a particle subjected to a deterministic inertial rocking system, under a constant bias, for which the phase of the symmetric spatial potential used is time modulated. We show that this modulated phase, assisted by a periodic driving force, can lead to the occurrence of the so-called absolute negative mobility (ANM), the phenomenon in which the particle surprisingly moves against the bias. Furthermore, we discover that ANM predominantly originates from chaotic-periodic transitions. While a detailed mechanism of ANM remains unclear, we show that one can manipulate the control parameters, i.e., the amplitude and the frequency of the phase, in order to enforce the motion of the particle in a given direction. Finally, for this experimentally realizable system, we devise a two-parameter current plot which may be a good guide for controlling ANM.

  11. Role of Absolute Humidity in the Inactivation of Influenza Viruses on Stainless Steel Surfaces at Elevated Temperatures ▿

    PubMed Central

    McDevitt, James; Rudnick, Stephen; First, Melvin; Spengler, John

    2010-01-01

    Influenza virus has been found to persist in the environment for hours to days, allowing for secondary transmission of influenza via inanimate objects known as fomites. We evaluated the efficacy of heat and moisture for the decontamination of surfaces for the purpose of preventing of the spread of influenza. Aqueous suspensions of influenza A virus were deposited onto stainless steel coupons, allowed to dry under ambient conditions, and exposed to temperatures of 55°C, 60°C, or 65°C and relative humidity (RH) of 25%, 50%, or 75% for up to 1 h. Quantitative virus assays were performed on the solution used to wash the viruses from these coupons, and results were compared with the solution used to wash coupons treated similarly but left under ambient conditions. Inactivation of influenza virus on surfaces increased with increasing temperature, RH, and exposure time. Reductions of greater than 5 logs of influenza virus on surfaces were achieved at temperatures of 60 and 65°C, exposure times of 30 and 60 min, and RH of 50 and 75%. Our data also suggest that absolute humidity is a better predictor of surface inactivation than RH and allows the prediction of survival using two parameters rather than three. Modest amounts of heat and adequate moisture can provide effective disinfection of surfaces while not harming surfaces, electrical systems, or mechanical components, leaving no harmful residues behind after treatment and requiring a relatively short amount of time. PMID:20435770

  12. Understanding the Temperature and Humidity Environment Inside a PV Module (Presentation)

    SciTech Connect

    Kempe, M.

    2013-06-01

    This presentation addresses moisture-driven degradation processes in PV modules and the conditions to use for accelerated stress testing. Here we show that by choosing humidity conditions that more closely match the use environment, one can minimize the uncertainty associated with moisture induced degradation modes.

  13. Uncertainty Estimation in Intensity-Modulated Radiotherapy Absolute Dosimetry Verification

    SciTech Connect

    Sanchez-Doblado, Francisco . E-mail: paco@us.es; Hartmann, Guenther H.; Pena, Javier; Capote, Roberto; Paiusco, Marta; Rhein, Bernhard; Leal, Antonio; Lagares, Juan Ignacio

    2007-05-01

    Purpose: Intensity-modulated radiotherapy (IMRT) represents an important method for improving RT. The IMRT relative dosimetry checks are well established; however, open questions remain in reference dosimetry with ionization chambers (ICs). The main problem is the departure of the measurement conditions from the reference ones; thus, additional uncertainty is introduced into the dose determination. The goal of this study was to assess this effect systematically. Methods and Materials: Monte Carlo calculations and dosimetric measurements with five different detectors were performed for a number of representative IMRT cases, covering both step-and-shoot and dynamic delivery. Results: Using ICs with volumes of about 0.125 cm{sup 3} or less, good agreement was observed among the detectors in most of the situations studied. These results also agreed well with the Monte Carlo-calculated nonreference correction factors (c factors). Additionally, we found a general correlation between the IC position relative to a segment and the derived correction factor c, which can be used to estimate the expected overall uncertainty of the treatment. Conclusion: The increase of the reference dose relative standard uncertainty measured with ICs introduced by nonreference conditions when verifying an entire IMRT plan is about 1-1.5%, provided that appropriate small-volume chambers are used. The overall standard uncertainty of the measured IMRT dose amounts to about 2.3%, including the 0.5% of reproducibility and 1.5% of uncertainty associated with the beam calibration factor. Solid state detectors and large-volume chambers are not well suited to IMRT verification dosimetry because of the greater uncertainties. An action level of 5% is appropriate for IMRT verification. Greater discrepancies should lead to a review of the dosimetric procedure, including visual inspection of treatment segments and energy fluence.

  14. Preliminary Investigations on the Effect of Humidity on the Reception of Visible Solar Radiation and the Effect of Humidity and Wind Speed on PV Module Output

    NASA Astrophysics Data System (ADS)

    Zainuddin, Hedzlin; Shaari, Sulaiman; Omar, Ahmad Maliki; Zain, Zainazlan Md.; Soumin, Jonson; Surat, Zainizam

    2010-07-01

    In order to improve the accuracy of methods currently used for characterizing the performance of photovoltaic (PV) arrays in their actual use environment, it is of importance to investigate the effect of ambient variables on the PV module output. Malaysia is a hot and humid country with relative humidity (RH) of 100% during rainfall and wind speed of greater than 4.0 ms-1 occurred about 8.4% in five years time. Therefore, the objective of this paper is to do a preliminary investigation on the effects of RH on the reception of solar radiation and the effect of humidity and wind speed on the PV module output. Outdoor field testing was conducted at Photovoltaic Monitoring Centre (PVMC), Universiti Teknologi MARA, of a BPSX-30U polycrystalline under variation of RH and wind speed separately. From the field testing, it was found that humidity reduced the amount of visible solar radiation reception, while humidity and wind speed both acts as cooling agents that increase the output of a PV module by reducing the module temperature.

  15. Temperature-modulated graphene oxide resistive humidity sensor for indoor air quality monitoring

    NASA Astrophysics Data System (ADS)

    de Luca, A.; Santra, S.; Ghosh, R.; Ali, S. Z.; Gardner, J. W.; Guha, P. K.; Udrea, F.

    2016-02-01

    In this paper we present a temperature-modulated graphene oxide (GO) resistive humidity sensor that employs complementary-metal-oxide-semiconductor (CMOS) micro-electro-mechanical-system (MEMS) micro-hotplate technology for the monitoring and control of indoor air quality (IAQ). GO powder is obtained by chemical exfoliation, dispersed in water and deposited via ink-jet printing onto a low power micro-hotplate. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) show the typical layered and wrinkled morphology of the GO. Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Fourier transform infra-red (FTIR) spectroscopy indicate that the GO flakes possess a significant number of oxygen containing functional groups (epoxy, carbonyl, hydroxyl) extremely attractive for humidity detection. Electro-thermal characterisation of the micro-hotplates shows a thermal efficiency of 0.11 mW per °C, resulting in a sensor DC power consumption of only 2.75 mW at 50 °C. When operated in an isothermal mode, the sensor response is detrimentally affected by significant drift, hysteretic behaviour, slow response/recovery times and hence poor RH level discrimination. Conversely, a temperature modulation technique coupled with a differential readout methodology results in a significant reduction of the sensor drift, improved linear response with a sensitivity of 0.14 mV per %, resolution below 5%, and a maximum hysteresis of +/-5% response and recovery times equal to 189 +/- 49 s and 89 +/- 5 s, respectively. These performance parameters satisfy current IAQ monitoring requirements. We have thus demonstrated the effectiveness of integrating GO on a micro-hotplate CMOS-compatible platform enabling temperature modulation schemes to be easily applied in order to achieve compact, low power, low cost humidity IAQ monitoring.In this paper we present a temperature-modulated graphene oxide (GO) resistive humidity sensor that employs complementary

  16. Full-field absolute phase measurements in the heterodyne interferometer with an electro-optic modulator

    NASA Astrophysics Data System (ADS)

    Chen, Y. L.; Hsieh, H. C.; Wu, W. T.; Su, D. C.

    2009-06-01

    A novel method for full-field absolute phase measurements in the heterodyne interferometer with an electro-optic modulator is proposed in this paper. Instead of the commonly-used half-wave voltage to drive the electro-optic modulator, a saw-tooth voltage signal with the amplitude being lower than its half-wave voltage is used. The interference signals become a group of periodical sinusoidal segments. The initial phase of each sinusoidal segment depends on the phase difference induced by the test sample. In real measurements, each segment is taken by a fast camera and becomes discrete digital points. After a series of operations, the starting point of the sampled sinusoidal segment can be determined accurately. Next, the period of the sampled sinusoidal segments is lengthened and they can be modified to a continuous sinusoidal wave by using a least-square sine fitting algorithm. The initial phase of the continuous sinusoidal wave can also be estimated. Subtracting the characteristic phase of the modulator from the initial phase, the absolute phase measured at the pixel can be obtained without the conventional reference signals. These operations are applied to other pixels, and the full-field absolute phase measurements can be achieved. The phase retardation of a quarter-wave plate is measured to show the validity of this method.

  17. Assessment of absolute added correlative coding in optical intensity modulation and direct detection channels

    NASA Astrophysics Data System (ADS)

    Dong-Nhat, Nguyen; Elsherif, Mohamed A.; Malekmohammadi, Amin

    2016-06-01

    The performance of absolute added correlative coding (AACC) modulation format with direct detection has been numerically and analytically reported, targeting metro data center interconnects. Hereby, the focus lies on the performance of the bit error rate, noise contributions, spectral efficiency, and chromatic dispersion tolerance. The signal space model of AACC, where the average electrical and optical power expressions are derived for the first time, is also delineated. The proposed modulation format was also compared to other well-known signaling, such as on-off-keying (OOK) and four-level pulse-amplitude modulation, at the same bit rate in a directly modulated vertical-cavity surface-emitting laser-based transmission system. The comparison results show a clear advantage of AACC in achieving longer fiber delivery distance due to the higher dispersion tolerance.

  18. Statistical data analysis of thin film photovoltaic modules deployed in hot and humid climate of Florida

    NASA Astrophysics Data System (ADS)

    Pethe, Shirish A.; Kaul, Ashwani; Dhere, Neelkanth G.

    2008-08-01

    Current accelerated tests of photovoltaic (PV) modules mostly prevent infant mortality but cannot duplicate changes occurring in the field nor can predict useful lifetime. Therefore, monitoring of field-deployed PV modules was undertaken at FSEC with goals to assess their performance in hot and humid climate under high voltage operation and to correlate the PV performance with the meteorological parameters. This paper presents performance analysis of U.S. Company manufactured thin film a-Si:H PV modules that are encapsulated using flexible front sheets and framed to be outdoor tested. Statistical data analysis of PV parameters along with meteorological parameters, monitored continuously, is carried out on regular basis with PVUSA type regression analysis. Current-voltage (I-V) characteristic of module arrays that are obtained periodically complement the continuous data monitoring. Moreover, effect of high voltage bias and ambient parameters on leakage current in PV modules on individual modules is studied. Any degradation occurring during initial 18 months could not be assessed due to data acquisition and hurricane problems. No significant degradation was observed in the performance of PV modules during the subsequent 30-months. It is planned to continue this study for a prolonged period so as to serve as basis for their long-term warranties.

  19. Temperature-modulated graphene oxide resistive humidity sensor for indoor air quality monitoring.

    PubMed

    De Luca, A; Santra, S; Ghosh, R; Ali, S Z; Gardner, J W; Guha, P K; Udrea, F

    2016-02-28

    In this paper we present a temperature-modulated graphene oxide (GO) resistive humidity sensor that employs complementary-metal-oxide-semiconductor (CMOS) micro-electro-mechanical-system (MEMS) micro-hotplate technology for the monitoring and control of indoor air quality (IAQ). GO powder is obtained by chemical exfoliation, dispersed in water and deposited via ink-jet printing onto a low power micro-hotplate. Atomic force microscopy (AFM) and transmission electron microscopy (TEM) show the typical layered and wrinkled morphology of the GO. Raman spectroscopy, X-ray photoelectron spectroscopy (XPS) and Fourier transform infra-red (FTIR) spectroscopy indicate that the GO flakes possess a significant number of oxygen containing functional groups (epoxy, carbonyl, hydroxyl) extremely attractive for humidity detection. Electro-thermal characterisation of the micro-hotplates shows a thermal efficiency of 0.11 mW per °C, resulting in a sensor DC power consumption of only 2.75 mW at 50 °C. When operated in an isothermal mode, the sensor response is detrimentally affected by significant drift, hysteretic behaviour, slow response/recovery times and hence poor RH level discrimination. Conversely, a temperature modulation technique coupled with a differential readout methodology results in a significant reduction of the sensor drift, improved linear response with a sensitivity of 0.14 mV per %, resolution below 5%, and a maximum hysteresis of ±5%; response and recovery times equal to 189 ± 49 s and 89 ± 5 s, respectively. These performance parameters satisfy current IAQ monitoring requirements. We have thus demonstrated the effectiveness of integrating GO on a micro-hotplate CMOS-compatible platform enabling temperature modulation schemes to be easily applied in order to achieve compact, low power, low cost humidity IAQ monitoring. PMID:26842731

  20. Intensity-modulated relative humidity sensing with polyvinyl alcohol coating and optical fiber gratings.

    PubMed

    Yang, Jingyi; Dong, Xinyong; Ni, Kai; Chan, Chi Chu; Shun, Perry Ping

    2015-04-01

    A relative humidity (RH) sensor in reflection mode is proposed and experimentally demonstrated by using a polyvinyl alcohol (PVA)-coated tilted-fiber Bragg grating (TFBG) cascaded by a reflection-band-matched chirped-fiber Bragg grating (CFBG). The sensing principle is based on the RH-dependent refractive index of the PVA coating, which modulates the transmission function of the TFBG. The CFBG is properly designed to reflect a broadband of light spectrally suited at the cladding mode resonance region of the TFBG, thus the reflected optical signal passes through and is modulated by the TFBG again. As a result, RH measurements with enhanced sensitivity of ∼1.80  μW/%RH are realized and demodulated in the range from 20% RH to 85% RH. PMID:25967167

  1. Use of the absolute phase in frequency modulated continuous wave plasma reflectometry

    SciTech Connect

    Cunningham, G.

    2008-08-15

    In frequency modulated continuous wave reflectometry, used for density profile measurement in fusion plasmas, it is usual to measure the beat frequency between the launched wave and the reflected wave, and from this to calculate the position of the reflecting layer in the plasma. The absolute phase of the beat signal is usually neglected. The reason is that the phase shift between sweeps is usually comparable with or more than 2{pi}, leading to an ambiguity that is impossible to resolve. However, recent observations on the MAST tokamak have shown that, under quiet plasma conditions (this term has to be defined), the phase shift between sweeps is small compared with 2{pi} and the phase ambiguity can be readily resolved. The reflectometer signal is then being analyzed as an interferometer signal would normally be, and there is a substantial improvement in spatial resolution. The method is illustrated by application to small edge localized mode precursor and allows what is believed to be the first quantitative measurement of the displacement of the plasma boundary by such a precursor mode. The errors in both the absolute phase measurement and the more conventional frequency measurement are also estimated.

  2. Comb-calibrated frequency-modulated continuous-wave ladar for absolute distance measurements.

    PubMed

    Baumann, Esther; Giorgetta, Fabrizio R; Coddington, Ian; Sinclair, Laura C; Knabe, Kevin; Swann, William C; Newbury, Nathan R

    2013-06-15

    We demonstrate a comb-calibrated frequency-modulated continuous-wave laser detection and ranging (FMCW ladar) system for absolute distance measurements. The FMCW ladar uses a compact external cavity laser that is swept quasi-sinusoidally over 1 THz at a 1 kHz rate. The system simultaneously records the heterodyne FMCW ladar signal and the instantaneous laser frequency at sweep rates up to 3400 THz/s, as measured against a free-running frequency comb (femtosecond fiber laser). Demodulation of the ladar signal against the instantaneous laser frequency yields the range to the target with 1 ms update rates, bandwidth-limited 130 μm resolution and a ~100 nm accuracy that is directly linked to the counted repetition rate of the comb. The precision is <100 nm at the 1 ms update rate and reaches ~6 nm for a 100 ms average. PMID:23938965

  3. Humidity-modulated phase control and nanoscopic transport in supramolecular assemblies.

    PubMed

    Chen, Ying; Lingwood, Mark D; Goswami, Mithun; Kidd, Bryce E; Hernandez, Jaime J; Rosenthal, Martin; Ivanov, Dimitri A; Perlich, Jan; Zhang, Heng; Zhu, Xiaomin; Möller, Martin; Madsen, Louis A

    2014-03-20

    Supramolecular assembly allows for enhanced control of bulk material properties through the fine modulation of intermolecular interactions. We present a comprehensive study of a cross-linkable amphiphilic wedge molecule based on a sulfonated trialkoxybenzene with a sodium counterion that forms liquid crystalline (LC) phases with ionic nanochannel structures. This compound exhibits drastic structural changes as a function of relative humidity (RH). Our combined structural, dynamical, and transport studies reveal deep and novel information on the coupling of water and wedge molecule transport to structural motifs, including the significant influence of domain boundaries within the material. Over a range of RH values, we employ (23)Na solid-state NMR on the counterions to complement detailed structural studies by grazing-incidence small-angle X-ray scattering. RH-dependent pulsed-field-gradient (PFG) NMR diffusion studies on both water and the wedge amphiphiles show multiple components, corresponding to species diffusing within LC domains as well as in the domain boundaries that compose 10% of the material. The rich transport and dynamical behaviors described here represent an important window into the world of supramolecular soft materials, carrying implications for optimization of these materials in many venues. Cubic phases present at high RH show fast transport of water (2 × 10(-10) m(2)/s), competitive with that observed in benchmark polymeric ion conductors. Understanding the self-assembly of these supramolecular building blocks shows promise for generating cross-linked membranes with fast ion conduction for applications such as next-generation batteries. PMID:24555816

  4. Absolute optical extinction measurements of single nano-objects by spatial modulation spectroscopy using a white lamp.

    PubMed

    Billaud, Pierre; Marhaba, Salem; Grillet, Nadia; Cottancin, Emmanuel; Bonnet, Christophe; Lermé, Jean; Vialle, Jean-Louis; Broyer, Michel; Pellarin, Michel

    2010-04-01

    This article describes a high sensitivity spectrophotometer designed to detect the overall extinction of light by a single nanoparticle (NP) in the 10(-4)-10(-5) relative range, using a transmission measurement configuration. We focus here on the simple and low cost scheme where a white lamp is used as a light source, permitting easy and broadband extinction measurements (300-900 nm). Using a microscope, in a confocal geometry, an increased sensitivity is reached thanks to a modulation of the NP position under the light spot combined with lock-in detection. Moreover, it is shown that this technique gives access to the absolute extinction cross-sections of the single NP provided that the incident electromagnetic field distribution experienced by the NP is accurately characterized. In this respect, an experimental procedure to characterize the light spot profile in the focal plane, using a reference NP as a probe, is also laid out. The validity of this approach is discussed and confirmed by comparing experimental intensity distributions to theoretical calculations taking into account the vector character of the tightly focused beam. The calibration procedure permitting to obtain the absolute extinction cross-section of the probed NP is then fully described. Finally, the force of the present technique is illustrated through selected examples concerning spherical and slightly elongated gold and silver NPs. Absolute extinction measurements are found to be in good consistency with the NP size and shape independently obtained from transmission electron microscopy, showing that spatial modulation spectroscopy is a powerful tool to get an optical fingerprint of the NP. PMID:20441319

  5. Modulation of Cenozoic climate by weathering of large igneous provinces on continents drifting through equatorial humid belt

    NASA Astrophysics Data System (ADS)

    Muttoni, G.; Kent, D. V.

    2011-12-01

    The small reservoir of CO2 in the atmosphere (pCO2) that modulates climate through the greenhouse effect is a delicate balance between large fluxes of sources and sinks. The major long-term source of CO2 is global degassing from sea-floor spreading, subduction, hotspot activity, and metamorphism; the ultimate sink is through weathering of continental silicates. Most carbon cycle models are driven by changes in the source flux, in particular, variable rates of ocean floor production (and concomitant subduction) but the area/age versus age distribution of the modern ocean is compatible with a steady rate since 180 Ma (Rowley, 2002 GSA Bulletin). We previously suggested (2008 PNAS) that evidence of high pCO2 and warm climates in the Cretaceous-early Cenozoic could be explained by the subduction of Tethyan ocean crust loaded with equatorial carbonate-rich pelagic (more readily subductable) sediments since the onset of India's northward flight at ~120 Ma up until the CO2-producing decarbonation factory slowed down with collision of India and Asia at the Early Eocene Climate Optimum at 50 Ma. At about this time, the India continent and the highly weatherable Deccan Traps drifted into the equatorial humid belt where uptake of CO2 by efficient silicate weathering would further lower the level of pCO2. Continued weathering uptake was influenced by the southerly extrusion of SE Asia in response to the Indian indentor starting at ~40 Ma (Molnar & Tapponnier, 1975 Science) as well as the emplacement of the Ethiopian traps near the Equator at 30 Ma. The ongoing impingement of India into Asia and resultant southerly tectonic extrusion of SE Asia (Replumaz & Tapponnier, 2003 JGR) makes it the dominant new area in the equatorial humid belt. Moreover, SE Asia presently accounts for 25% of CO2 consumption of all basaltic provinces, which account for ~1/3 of the total consumption by continental silicate weathering (Dessert et al., 2003 Chemical Geology) that is within the range of

  6. Modulation of Terrestrial Convection by Tropospheric Humidity, and Implications for Other Planets

    NASA Technical Reports Server (NTRS)

    Genio, Anthony Del

    2013-01-01

    For decades, deep cumulus convection was viewed as consisting partly of undilute plumes that do not interact with their surrounding environment in order to explain their observed tendency to reach or penetrate the tropical tropopause. This behavior was built into all cumulus parameterizations used in terrestrial global climate and numerical weather prediction models, and it still persists in some models today. In the past decade, though, some embarrassing failures of global models have come to light, notably their tendency to rain over land near noon rather than in late afternoon or evening as observed, and the absence in the models of the Madden-Julian Oscillation (MJO), the major source of intraseasonal (30-90 day) precipitation variability in the Indian Ocean, West Pacific, and surrounding continental regions. In the past decade it has become clear that an important missing component of parameterizations is strong turbulent entrainment of drier environmental air into cumulus updrafts, which reduces the buoyancy of the updrafts and thus limits their vertical development. Tropospheric humidity thus serves as a throttle on convective penetration to high altitudes and delays the convective response to large-scale destabilizing influences in the environment.

  7. Easy Absolute Values? Absolutely

    ERIC Educational Resources Information Center

    Taylor, Sharon E.; Mittag, Kathleen Cage

    2015-01-01

    The authors teach a problem-solving course for preservice middle-grades education majors that includes concepts dealing with absolute-value computations, equations, and inequalities. Many of these students like mathematics and plan to teach it, so they are adept at symbolic manipulations. Getting them to think differently about a concept that they…

  8. 40 CFR 89.326 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air humidity measurement... Test Equipment Provisions § 89.326 Engine intake air humidity measurement. (a) Humidity conditioned air supply. Air that has had its absolute humidity altered is considered humidity- conditioned air. For...

  9. 40 CFR 89.326 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air humidity measurement... Test Equipment Provisions § 89.326 Engine intake air humidity measurement. (a) Humidity conditioned air supply. Air that has had its absolute humidity altered is considered humidity- conditioned air. For...

  10. 40 CFR 89.326 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air humidity measurement... Test Equipment Provisions § 89.326 Engine intake air humidity measurement. (a) Humidity conditioned air supply. Air that has had its absolute humidity altered is considered humidity- conditioned air. For...

  11. 40 CFR 89.326 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air humidity measurement... Test Equipment Provisions § 89.326 Engine intake air humidity measurement. (a) Humidity conditioned air supply. Air that has had its absolute humidity altered is considered humidity- conditioned air. For...

  12. 40 CFR 89.326 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air humidity measurement... Test Equipment Provisions § 89.326 Engine intake air humidity measurement. (a) Humidity conditioned air supply. Air that has had its absolute humidity altered is considered humidity- conditioned air. For...

  13. Wavelength-modulated differential photoacoustic radar imager (WM-DPARI): accurate monitoring of absolute hemoglobin oxygen saturation

    PubMed Central

    Choi, Sung Soo Sean; Lashkari, Bahman; Dovlo, Edem; Mandelis, Andreas

    2016-01-01

    Accurate monitoring of blood oxy-saturation level (SO2) in human breast tissues is clinically important for predicting and evaluating possible tumor growth at the site. In this work, four different non-invasive frequency-domain photoacoustic (PA) imaging modalities were compared for their absolute SO2 characterization capability using an in-vitro sheep blood circulation system. Among different PA modes, a new WM-DPAR imaging modality could estimate the SO2 with great accuracy when compared to a commercial blood gas analyzer. The developed WM-DPARI theory was further validated by constructing SO2 tomographic images of a blood-containing plastisol phantom. PMID:27446691

  14. Wavelength-modulated differential photoacoustic radar imager (WM-DPARI): accurate monitoring of absolute hemoglobin oxygen saturation.

    PubMed

    Choi, Sung Soo Sean; Lashkari, Bahman; Dovlo, Edem; Mandelis, Andreas

    2016-07-01

    Accurate monitoring of blood oxy-saturation level (SO2 ) in human breast tissues is clinically important for predicting and evaluating possible tumor growth at the site. In this work, four different non-invasive frequency-domain photoacoustic (PA) imaging modalities were compared for their absolute SO2 characterization capability using an in-vitro sheep blood circulation system. Among different PA modes, a new WM-DPAR imaging modality could estimate the SO2 with great accuracy when compared to a commercial blood gas analyzer. The developed WM-DPARI theory was further validated by constructing SO2 tomographic images of a blood-containing plastisol phantom. PMID:27446691

  15. Examination of humidity effects on measured thickness and interfacial phenomena of exfoliated graphene on silicon dioxide via amplitude modulation atomic force microscopy

    NASA Astrophysics Data System (ADS)

    Jinkins, K.; Camacho, J.; Farina, L.; Wu, Y.

    2015-12-01

    The properties of Few-Layer Graphene (FLG) change with the number of layers and Amplitude Modulation (AM) Atomic Force Microscopy (AFM) is commonly used to determine the thickness of FLG. However, AFM measurements have been shown to be sensitive to environmental conditions such as relative humidity (RH). In the present study, AM-AFM is used to measure the thickness and loss tangent of exfoliated graphene on silicon dioxide (SiO2) as RH is increased from 10% to 80%. We show that the measured thickness of graphene is dependent on RH. The loss tangent values of the graphene and oxide regions are both affected by humidity, with generally higher loss tangent for graphene than SiO2. As RH increases, we observe the loss tangent of both materials approaches the same value. We hypothesize that there is a layer of water trapped between the graphene and SiO2 substrate to explain this observation. Using this interpretation, the loss tangent images also indicate movement and change in this trapped water layer as RH increases, which impacts the measured thickness of graphene using AM-AFM.

  16. Examination of humidity effects on measured thickness and interfacial phenomena of exfoliated graphene on silicon dioxide via amplitude modulation atomic force microscopy

    SciTech Connect

    Jinkins, K.; Farina, L.; Wu, Y.; Camacho, J.

    2015-12-14

    The properties of Few-Layer Graphene (FLG) change with the number of layers and Amplitude Modulation (AM) Atomic Force Microscopy (AFM) is commonly used to determine the thickness of FLG. However, AFM measurements have been shown to be sensitive to environmental conditions such as relative humidity (RH). In the present study, AM-AFM is used to measure the thickness and loss tangent of exfoliated graphene on silicon dioxide (SiO{sub 2}) as RH is increased from 10% to 80%. We show that the measured thickness of graphene is dependent on RH. The loss tangent values of the graphene and oxide regions are both affected by humidity, with generally higher loss tangent for graphene than SiO{sub 2}. As RH increases, we observe the loss tangent of both materials approaches the same value. We hypothesize that there is a layer of water trapped between the graphene and SiO{sub 2} substrate to explain this observation. Using this interpretation, the loss tangent images also indicate movement and change in this trapped water layer as RH increases, which impacts the measured thickness of graphene using AM-AFM.

  17. Upper tropospheric humidity changes under constant relative humidity

    NASA Astrophysics Data System (ADS)

    Gierens, Klaus; Eleftheratos, Kostas

    2016-03-01

    Theoretical derivations are given on the change of upper tropospheric humidity (UTH) in a warming climate. The considered view is that the atmosphere, which is getting moister with increasing temperatures, will retain a constant relative humidity. In the present study, we show that the upper tropospheric humidity, a weighted mean over a relative humidity profile, will change in spite of constant relative humidity. The simple reason for this is that the weighting function that defines UTH changes in a moister atmosphere. Through analytical calculations using observations and through radiative transfer calculations, we demonstrate that two quantities that define the weighting function of UTH can change: the water vapour scale height and the peak emission altitude. Applying these changes to real profiles of relative humidity shows that absolute UTH changes typically do not exceed 1 %. If larger changes would be observed they would be an indication of climatological changes of relative humidity. As such, an increase in UTH between 1980 and 2009 in the northern midlatitudes, as shown by earlier studies using the High-resolution Infrared Radiation Sounder (HIRS) data, may be an indication of an increase in relative humidity as well.

  18. Upper-tropospheric humidity changes under constant relative humidity

    NASA Astrophysics Data System (ADS)

    Gierens, K.; Eleftheratos, K.

    2015-10-01

    Theoretical derivations are given on the change of upper-tropospheric humidity (UTH) in a warming climate. Considered view is that the atmosphere, getting moister with increasing temperatures, will retain a constant relative humidity. In the present study we show that the upper-tropospheric humidity, a weighted mean over a relative humidity profile, will change in spite of constant relative humidity. The simple reason for this is that the weighting function, that defines UTH, changes in a moister atmosphere. Through analytical calculations using observations and through radiative transfer calculations we demonstrate that two quantities that define the weighting function of UTH can change: the water vapour scale height and the peak emission altitude. Applying these changes to real profiles of relative humidity shows that absolute UTH changes typically do not exceed 1 %. If larger changes would be observed they would be an indication of climatological changes of relative humidity. As such, an increase in UTH between 1980 and 2009 in the northern midlatitudes as shown by earlier studies using HIRS data, may be an indication of an increase in relative humidity as well.

  19. EDITORIAL: Humidity sensors Humidity sensors

    NASA Astrophysics Data System (ADS)

    Regtien, Paul P. L.

    2012-01-01

    All matter is more or less hygroscopic. The moisture content varies with vapour concentration of the surrounding air and, as a consequence, most material properties change with humidity. Mechanical and thermal properties of many materials, such as the tensile strength of adhesives, stiffness of plastics, stoutness of building and packaging materials or the thermal resistivity of isolation materials, all decrease with increasing environmental humidity or cyclic humidity changes. The presence of water vapour may have a detrimental influence on many electrical constructions and systems exposed to humid air, from high-power systems to microcircuits. Water vapour penetrates through coatings, cable insulations and integrated-circuit packages, exerting a fatal influence on the performance of the enclosed systems. For these and many other applications, knowledge of the relationship between moisture content or humidity and material properties or system behaviour is indispensable. This requires hygrometers for process control or test and calibration chambers with high accuracy in the appropriate temperature and humidity range. Humidity measurement methods can roughly be categorized into four groups: water vapour removal (the mass before and after removal is measured); saturation (the air is brought to saturation and the `effort' to reach that state is measured); humidity-dependent parameters (measurement of properties of humid air with a known relation between a specific property and the vapour content, for instance the refractive index, electromagnetic spectrum and acoustic velocity); and absorption (based on the known relation between characteristic properties of non-hydrophobic materials and the amount of absorbed water from the gas to which these materials are exposed). The many basic principles to measure air humidity are described in, for instance, the extensive compilations by Wexler [1] and Sonntag [2]. Absorption-type hygrometers have small dimensions and can be

  20. An absolute calibration method of an ethyl alcohol biosensor based on wavelength-modulated differential photothermal radiometry.

    PubMed

    Liu, Yi Jun; Mandelis, Andreas; Guo, Xinxin

    2015-11-01

    In this work, laser-based wavelength-modulated differential photothermal radiometry (WM-DPTR) is applied to develop a non-invasive in-vehicle alcohol biosensor. WM-DPTR features unprecedented ethanol-specificity and sensitivity by suppressing baseline variations through a differential measurement near the peak and baseline of the mid-infrared ethanol absorption spectrum. Biosensor signal calibration curves are obtained from WM-DPTR theory and from measurements in human blood serum and ethanol solutions diffused from skin. The results demonstrate that the WM-DPTR-based calibrated alcohol biosensor can achieve high precision and accuracy for the ethanol concentration range of 0-100 mg/dl. The high-performance alcohol biosensor can be incorporated into ignition interlocks that could be fitted as a universal accessory in vehicles in an effort to reduce incidents of drinking and driving. PMID:26628164

  1. An absolute calibration method of an ethyl alcohol biosensor based on wavelength-modulated differential photothermal radiometry

    SciTech Connect

    Liu, Yi Jun; Mandelis, Andreas; Guo, Xinxin

    2015-11-15

    In this work, laser-based wavelength-modulated differential photothermal radiometry (WM-DPTR) is applied to develop a non-invasive in-vehicle alcohol biosensor. WM-DPTR features unprecedented ethanol-specificity and sensitivity by suppressing baseline variations through a differential measurement near the peak and baseline of the mid-infrared ethanol absorption spectrum. Biosensor signal calibration curves are obtained from WM-DPTR theory and from measurements in human blood serum and ethanol solutions diffused from skin. The results demonstrate that the WM-DPTR-based calibrated alcohol biosensor can achieve high precision and accuracy for the ethanol concentration range of 0-100 mg/dl. The high-performance alcohol biosensor can be incorporated into ignition interlocks that could be fitted as a universal accessory in vehicles in an effort to reduce incidents of drinking and driving.

  2. An absolute calibration method of an ethyl alcohol biosensor based on wavelength-modulated differential photothermal radiometry

    NASA Astrophysics Data System (ADS)

    Liu, Yi Jun; Mandelis, Andreas; Guo, Xinxin

    2015-11-01

    In this work, laser-based wavelength-modulated differential photothermal radiometry (WM-DPTR) is applied to develop a non-invasive in-vehicle alcohol biosensor. WM-DPTR features unprecedented ethanol-specificity and sensitivity by suppressing baseline variations through a differential measurement near the peak and baseline of the mid-infrared ethanol absorption spectrum. Biosensor signal calibration curves are obtained from WM-DPTR theory and from measurements in human blood serum and ethanol solutions diffused from skin. The results demonstrate that the WM-DPTR-based calibrated alcohol biosensor can achieve high precision and accuracy for the ethanol concentration range of 0-100 mg/dl. The high-performance alcohol biosensor can be incorporated into ignition interlocks that could be fitted as a universal accessory in vehicles in an effort to reduce incidents of drinking and driving.

  3. Absolute Zero

    NASA Astrophysics Data System (ADS)

    Donnelly, Russell J.; Sheibley, D.; Belloni, M.; Stamper-Kurn, D.; Vinen, W. F.

    2006-12-01

    Absolute Zero is a two hour PBS special attempting to bring to the general public some of the advances made in 400 years of thermodynamics. It is based on the book “Absolute Zero and the Conquest of Cold” by Tom Shachtman. Absolute Zero will call long-overdue attention to the remarkable strides that have been made in low-temperature physics, a field that has produced 27 Nobel Prizes. It will explore the ongoing interplay between science and technology through historical examples including refrigerators, ice machines, frozen foods, liquid oxygen and nitrogen as well as much colder fluids such as liquid hydrogen and liquid helium. A website has been established to promote the series: www.absolutezerocampaign.org. It contains information on the series, aimed primarily at students at the middle school level. There is a wealth of material here and we hope interested teachers will draw their student’s attention to this website and its substantial contents, which have been carefully vetted for accuracy.

  4. Fuel Oxidizer Reaction Products (FORP) Contamination of Service Module (SM) and Release of N-nitrosodimethylamine(NDMA)in a Humid Environment from Crew EVA Suits Contaminated with FORP

    NASA Technical Reports Server (NTRS)

    Schmidl, William; Mikatarian, Ron; Lam, Chiu-Wing; West, Bil; Buchanan, Vanessa; Dee, Louis; Baker, David; Koontz, Steve

    2004-01-01

    The Service Module (SM) is an element of the Russian Segment of the International Space Station (ISS). One of the functions of the SM is to provide attitude control for the ISS using thrusters when the U.S. Control Moment Gyros (CMG's) must be desaturated. Prior to an Extravehicular Activity (EVA) on the Russian Segment, the Docking Compartment (DC1) is depressurized, as it is used as an airlock. When the DC1 is depressurized, the CMG's margin of momentum is insufficient and the SM attitude control thrusters need to fire to desaturate the CMG's. SM roll thruster firings induce contamination onto adjacent surfaces with Fuel Oxidizer Reaction Products (FORP). FORP is composed of both volatile and non-volatile components. One of the components of FORP is the potent carcinogen N-nitrosdimethylamine (NDMA). Since the EVA crewmembers often enter the area surrounding the thrusters for tasks on the aft end of the SM and when translating to other areas of the Russian Segment, the presence of FORP is a concern. This paper will discuss FORP contamination of the SM surfaces, the release of NDMA in a humid environment from crew EVA suits, if they happen to be contaminated with FORP, and the toxicological risk associated with the NDMA release.

  5. Absolute Summ

    NASA Astrophysics Data System (ADS)

    Phillips, Alfred, Jr.

    Summ means the entirety of the multiverse. It seems clear, from the inflation theories of A. Guth and others, that the creation of many universes is plausible. We argue that Absolute cosmological ideas, not unlike those of I. Newton, may be consistent with dynamic multiverse creations. As suggested in W. Heisenberg's uncertainty principle, and with the Anthropic Principle defended by S. Hawking, et al., human consciousness, buttressed by findings of neuroscience, may have to be considered in our models. Predictability, as A. Einstein realized with Invariants and General Relativity, may be required for new ideas to be part of physics. We present here a two postulate model geared to an Absolute Summ. The seedbed of this work is part of Akhnaton's philosophy (see S. Freud, Moses and Monotheism). Most important, however, is that the structure of human consciousness, manifest in Kenya's Rift Valley 200,000 years ago as Homo sapiens, who were the culmination of the six million year co-creation process of Hominins and Nature in Africa, allows us to do the physics that we do. .

  6. Photogated humidity-driven motility

    PubMed Central

    Zhang, Lidong; Liang, Haoran; Jacob, Jolly; Naumov, Panče

    2015-01-01

    Hygroinduced motion is a fundamental process of energy conversion that is essential for applications that require contactless actuation in response to the day–night rhythm of atmospheric humidity. Here we demonstrate that mechanical bistability caused by rapid and anisotropic adsorption and desorption of water vapour by a flexible dynamic element that harnesses the chemical potential across very small humidity gradients for perpetual motion can be effectively modulated with light. A mechanically robust material capable of rapid exchange of water with the surroundings is prepared that undergoes swift locomotion in effect to periodic shape reconfiguration with turnover frequency of <150 min−1. The element can lift objects ∼85 times heavier and can transport cargos ∼20 times heavier than itself. Having an azobenzene-containing conjugate as a photoactive dopant, this entirely humidity-driven self-actuation can be controlled remotely with ultraviolet light, thus setting a platform for next-generation smart biomimetic hybrids. PMID:26067649

  7. Photogated humidity-driven motility

    NASA Astrophysics Data System (ADS)

    Zhang, Lidong; Liang, Haoran; Jacob, Jolly; Naumov, Panče

    2015-06-01

    Hygroinduced motion is a fundamental process of energy conversion that is essential for applications that require contactless actuation in response to the day-night rhythm of atmospheric humidity. Here we demonstrate that mechanical bistability caused by rapid and anisotropic adsorption and desorption of water vapour by a flexible dynamic element that harnesses the chemical potential across very small humidity gradients for perpetual motion can be effectively modulated with light. A mechanically robust material capable of rapid exchange of water with the surroundings is prepared that undergoes swift locomotion in effect to periodic shape reconfiguration with turnover frequency of <150 min-1. The element can lift objects ~85 times heavier and can transport cargos ~20 times heavier than itself. Having an azobenzene-containing conjugate as a photoactive dopant, this entirely humidity-driven self-actuation can be controlled remotely with ultraviolet light, thus setting a platform for next-generation smart biomimetic hybrids.

  8. Humidity trends imply increased sensitivity to clouds in a warming Arctic.

    PubMed

    Cox, Christopher J; Walden, Von P; Rowe, Penny M; Shupe, Matthew D

    2015-01-01

    Infrared radiative processes are implicated in Arctic warming and sea-ice decline. The infrared cloud radiative effect (CRE) at the surface is modulated by cloud properties; however, CRE also depends on humidity because clouds emit at wavelengths that are semi-transparent to greenhouse gases, most notably water vapour. Here we show how temperature and humidity control CRE through competing influences between the mid- and far-infrared. At constant relative humidity, CRE does not decrease with increasing temperature/absolute humidity as expected, but rather is found to be approximately constant for temperatures characteristic of the Arctic. This stability is disrupted if relative humidity varies. Our findings explain observed seasonal and regional variability in Arctic CRE of order 10 W m(-2). With the physical properties of Arctic clouds held constant, we calculate recent increases in CRE of 1-5 W m(-2) in autumn and winter, which are projected to reach 5-15 W m(-2) by 2050, implying increased sensitivity of the surface to clouds. PMID:26657324

  9. Humidity trends imply increased sensitivity to clouds in a warming Arctic

    PubMed Central

    Cox, Christopher J.; Walden, Von P.; Rowe, Penny M.; Shupe, Matthew D.

    2015-01-01

    Infrared radiative processes are implicated in Arctic warming and sea-ice decline. The infrared cloud radiative effect (CRE) at the surface is modulated by cloud properties; however, CRE also depends on humidity because clouds emit at wavelengths that are semi-transparent to greenhouse gases, most notably water vapour. Here we show how temperature and humidity control CRE through competing influences between the mid- and far-infrared. At constant relative humidity, CRE does not decrease with increasing temperature/absolute humidity as expected, but rather is found to be approximately constant for temperatures characteristic of the Arctic. This stability is disrupted if relative humidity varies. Our findings explain observed seasonal and regional variability in Arctic CRE of order 10 W m−2. With the physical properties of Arctic clouds held constant, we calculate recent increases in CRE of 1–5 W m−2 in autumn and winter, which are projected to reach 5–15 W m−2 by 2050, implying increased sensitivity of the surface to clouds. PMID:26657324

  10. Humidity trends imply increased sensitivity to clouds in a warming Arctic

    SciTech Connect

    Cox, Christopher J.; Walden, Von P.; Rowe, Penny M.; Shupe, Matthew D.

    2015-12-10

    Infrared radiative processes are implicated in Arctic warming and sea-ice decline. The infrared cloud radiative effect (CRE) at the surface is modulated by cloud properties; however, CRE also depends on humidity because clouds emit at wavelengths that are semi-transparent to greenhouse gases, most notably water vapour. Here we show how temperature and humidity control CRE through competing influences between the mid- and far-infrared. At constant relative humidity, CRE does not decrease with increasing temperature/absolute humidity as expected, but rather is found to be approximately constant for temperatures characteristic of the Arctic. This stability is disrupted if relative humidity varies. Our findings explain observed seasonal and regional variability in Arctic CRE of order 10Wm 2. With the physical properties of Arctic clouds held constant, we calculate recent increases in CRE of 1–5Wm 2 in autumn and winter, which are projected to reach 5–15Wm 2 by 2050, implying increased sensitivity of the surface to clouds.

  11. Humidity trends imply increased sensitivity to clouds in a warming Arctic

    DOE PAGESBeta

    Cox, Christopher J.; Walden, Von P.; Rowe, Penny M.; Shupe, Matthew D.

    2015-12-10

    Infrared radiative processes are implicated in Arctic warming and sea-ice decline. The infrared cloud radiative effect (CRE) at the surface is modulated by cloud properties; however, CRE also depends on humidity because clouds emit at wavelengths that are semi-transparent to greenhouse gases, most notably water vapour. Here we show how temperature and humidity control CRE through competing influences between the mid- and far-infrared. At constant relative humidity, CRE does not decrease with increasing temperature/absolute humidity as expected, but rather is found to be approximately constant for temperatures characteristic of the Arctic. This stability is disrupted if relative humidity varies. Ourmore » findings explain observed seasonal and regional variability in Arctic CRE of order 10Wm 2. With the physical properties of Arctic clouds held constant, we calculate recent increases in CRE of 1–5Wm 2 in autumn and winter, which are projected to reach 5–15Wm 2 by 2050, implying increased sensitivity of the surface to clouds.« less

  12. Humidity trends imply increased sensitivity to clouds in a warming Arctic

    NASA Astrophysics Data System (ADS)

    Cox, Christopher; Walden, Von; Rowe, Penny; Shupe, Matthew

    2016-04-01

    Infrared radiative processes are implicated in Arctic warming and sea-ice decline. The infrared cloud radiative effect (CRE) at the surface is modulated by cloud properties, but CRE also depends on humidity because clouds emit at wavelengths that are semi-transparent to greenhouse gases, most notably water vapour. Here we show how temperature and humidity control CRE through competing influences between the mid- and far-infrared. At constant relative humidity, CRE does not decrease with increasing temperature/absolute humidity as expected, but rather is found to be approximately constant for temperatures characteristic of the Arctic. This stability is disrupted if relative humidity varies. Our findings explain observed seasonal and regional variability in Arctic CRE of order 10 W m-2. With the physical properties of Arctic clouds held constant, we calculate recent increases in CRE of 1-5 W m-2 in autumn and winter, which are projected to reach 5-15 W m-2 by 2050, implying increased sensitivity of the surface to clouds.

  13. Humidity trends imply increased sensitivity to clouds in a warming Arctic

    NASA Astrophysics Data System (ADS)

    Cox, Christopher J.; Walden, Von P.; Rowe, Penny M.; Shupe, Matthew D.

    2015-12-01

    Infrared radiative processes are implicated in Arctic warming and sea-ice decline. The infrared cloud radiative effect (CRE) at the surface is modulated by cloud properties; however, CRE also depends on humidity because clouds emit at wavelengths that are semi-transparent to greenhouse gases, most notably water vapour. Here we show how temperature and humidity control CRE through competing influences between the mid- and far-infrared. At constant relative humidity, CRE does not decrease with increasing temperature/absolute humidity as expected, but rather is found to be approximately constant for temperatures characteristic of the Arctic. This stability is disrupted if relative humidity varies. Our findings explain observed seasonal and regional variability in Arctic CRE of order 10 W m-2. With the physical properties of Arctic clouds held constant, we calculate recent increases in CRE of 1-5 W m-2 in autumn and winter, which are projected to reach 5-15 W m-2 by 2050, implying increased sensitivity of the surface to clouds.

  14. Measuring Relative Humidity.

    ERIC Educational Resources Information Center

    Pinkham, Chester A.; Barrett, Kristin Burrows

    1992-01-01

    Describes four experiments that enable students to explore the phenomena of evaporation and condensation and determine the relative humidity by measuring air temperature and dew point on warm September days. Provides tables to calculate saturation points and relative humidity. (MDH)

  15. Absolute optical metrology : nanometers to kilometers

    NASA Technical Reports Server (NTRS)

    Dubovitsky, Serge; Lay, O. P.; Peters, R. D.; Liebe, C. C.

    2005-01-01

    We provide and overview of the developments in the field of 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.

  16. Teaching Absolute Value Meaningfully

    ERIC Educational Resources Information Center

    Wade, Angela

    2012-01-01

    What is the meaning of absolute value? And why do teachers teach students how to solve absolute value equations? Absolute value is a concept introduced in first-year algebra and then reinforced in later courses. Various authors have suggested instructional methods for teaching absolute value to high school students (Wei 2005; Stallings-Roberts…

  17. [Alchemists' humid radical].

    PubMed

    Lafont, Olivier

    2007-01-01

    The term radical has been used by chemists since the beginnings and even when they still were alchemists. The term "humid radical" is present in numerous alchemists' texts. It was used to represent a kind of "humid", which was considered as different from what is nowadays called "humid", but was a sort of principle necessary for life. PMID:17575839

  18. Eosinophil count - absolute

    MedlinePlus

    Eosinophils; Absolute eosinophil count ... the white blood cell count to give the absolute eosinophil count. ... than 500 cells per microliter (cells/mcL). Normal value ranges may vary slightly among different laboratories. Talk ...

  19. Sensitivity of Honeybee Hygroreceptors to Slow Humidity Changes and Temporal Humidity Variation Detected in High Resolution by Mobile Measurements

    PubMed Central

    Tichy, Harald; Kallina, Wolfgang

    2014-01-01

    The moist cell and the dry cell on the antenna of the male honeybee were exposed to humidities slowly rising and falling at rates between –1.5%/s and +1.5%/s and at varying amplitudes in the 10 to 90% humidity range. The two cells respond to these slow humidity oscillations with oscillations in impulse frequency which depend not only on instantaneous humidity but also on the rate with which humidity changes. The impulse frequency of each cell was plotted as a function of these two parameters and regression planes were fitted to the data points of single oscillation periods. The regression slopes, which estimate sensitivity, rose with the amplitude of humidity oscillations. During large-amplitude oscillations, moist and dry cell sensitivity for instantaneous humidity and its rate of change was high. During small-amplitude oscillations, their sensitivity for both parameters was low, less exactly reflecting humidity fluctuations. Nothing is known about the spatial and temporal humidity variations a honeybee may encounter when flying through natural environments. Microclimatic parameters (absolute humidity, temperature, wind speed) were measured from an automobile traveling through different landscapes of Lower Austria. Landscape type affected extremes and mean values of humidity. Differences between peaks and troughs of humidity fluctuations were generally smaller in open grassy fields or deciduous forests than in edge habitats or forest openings. Overall, fluctuation amplitudes were small. In this part of the stimulus range, hygroreceptor sensitivity is not optimal for encoding instantaneous humidity and the rate of humidity change. It seems that honeybee's hygroreceptors are specialized for detecting large-amplitude fluctuations that are relevant for a specific behavior, namely, maintaining a sufficiently stable state of water balance. The results suggest that optimal sensitivity of both hygroreceptors is shaped not only by humidity oscillation amplitudes but also

  20. Sensitivity of honeybee hygroreceptors to slow humidity changes and temporal humidity variation detected in high resolution by mobile measurements.

    PubMed

    Tichy, Harald; Kallina, Wolfgang

    2014-01-01

    The moist cell and the dry cell on the antenna of the male honeybee were exposed to humidities slowly rising and falling at rates between -1.5%/s and +1.5%/s and at varying amplitudes in the 10 to 90% humidity range. The two cells respond to these slow humidity oscillations with oscillations in impulse frequency which depend not only on instantaneous humidity but also on the rate with which humidity changes. The impulse frequency of each cell was plotted as a function of these two parameters and regression planes were fitted to the data points of single oscillation periods. The regression slopes, which estimate sensitivity, rose with the amplitude of humidity oscillations. During large-amplitude oscillations, moist and dry cell sensitivity for instantaneous humidity and its rate of change was high. During small-amplitude oscillations, their sensitivity for both parameters was low, less exactly reflecting humidity fluctuations. Nothing is known about the spatial and temporal humidity variations a honeybee may encounter when flying through natural environments. Microclimatic parameters (absolute humidity, temperature, wind speed) were measured from an automobile traveling through different landscapes of Lower Austria. Landscape type affected extremes and mean values of humidity. Differences between peaks and troughs of humidity fluctuations were generally smaller in open grassy fields or deciduous forests than in edge habitats or forest openings. Overall, fluctuation amplitudes were small. In this part of the stimulus range, hygroreceptor sensitivity is not optimal for encoding instantaneous humidity and the rate of humidity change. It seems that honeybee's hygroreceptors are specialized for detecting large-amplitude fluctuations that are relevant for a specific behavior, namely, maintaining a sufficiently stable state of water balance. The results suggest that optimal sensitivity of both hygroreceptors is shaped not only by humidity oscillation amplitudes but also

  1. The conditions of absolute summability of multiple trigonometric series

    NASA Astrophysics Data System (ADS)

    Bitimkhan, Samat; Akishev, Gabdolla

    2015-09-01

    In this work necessary and sufficient conditions of absolute summability of multiple trigonometric Fourier series of functions from anisotropic spaces of Lebesque are found in terms of its best approximation, the module of smoothness and the mixed smoothness module.

  2. Absolute nuclear material assay

    DOEpatents

    Prasad, Manoj K.; Snyderman, Neal J.; Rowland, Mark S.

    2012-05-15

    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.

  3. Absolute nuclear material assay

    DOEpatents

    Prasad, Manoj K.; Snyderman, Neal J.; Rowland, Mark S.

    2010-07-13

    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.

  4. Using Multivariate Regression Model with Least Absolute Shrinkage and Selection Operator (LASSO) to Predict the Incidence of Xerostomia after Intensity-Modulated Radiotherapy for Head and Neck Cancer

    PubMed Central

    Ting, Hui-Min; Chang, Liyun; Huang, Yu-Jie; Wu, Jia-Ming; Wang, Hung-Yu; Horng, Mong-Fong; Chang, Chun-Ming; Lan, Jen-Hong; Huang, Ya-Yu; Fang, Fu-Min; Leung, Stephen Wan

    2014-01-01

    Purpose The aim of this study was to develop a multivariate logistic regression model with least absolute shrinkage and selection operator (LASSO) to make valid predictions about the incidence of moderate-to-severe patient-rated xerostomia among head and neck cancer (HNC) patients treated with IMRT. Methods and Materials Quality of life questionnaire datasets from 206 patients with HNC were analyzed. The European Organization for Research and Treatment of Cancer QLQ-H&N35 and QLQ-C30 questionnaires were used as the endpoint evaluation. The primary endpoint (grade 3+ xerostomia) was defined as moderate-to-severe xerostomia at 3 (XER3m) and 12 months (XER12m) after the completion of IMRT. Normal tissue complication probability (NTCP) models were developed. The optimal and suboptimal numbers of prognostic factors for a multivariate logistic regression model were determined using the LASSO with bootstrapping technique. Statistical analysis was performed using the scaled Brier score, Nagelkerke R2, chi-squared test, Omnibus, Hosmer-Lemeshow test, and the AUC. Results Eight prognostic factors were selected by LASSO for the 3-month time point: Dmean-c, Dmean-i, age, financial status, T stage, AJCC stage, smoking, and education. Nine prognostic factors were selected for the 12-month time point: Dmean-i, education, Dmean-c, smoking, T stage, baseline xerostomia, alcohol abuse, family history, and node classification. In the selection of the suboptimal number of prognostic factors by LASSO, three suboptimal prognostic factors were fine-tuned by Hosmer-Lemeshow test and AUC, i.e., Dmean-c, Dmean-i, and age for the 3-month time point. Five suboptimal prognostic factors were also selected for the 12-month time point, i.e., Dmean-i, education, Dmean-c, smoking, and T stage. The overall performance for both time points of the NTCP model in terms of scaled Brier score, Omnibus, and Nagelkerke R2 was satisfactory and corresponded well with the expected values. Conclusions

  5. Group 3: Humidity, Temperature and Voltage (Presentation)

    SciTech Connect

    Wohlgemuth, J.

    2013-09-01

    This is a summary of the work of Group 3 of the International PV QA Task Force. Group 3 is chartered to develop accelerated stress tests that can be used as comparative predictors of module lifetime versus stresses associated with humidity, temperature and voltage.

  6. Research on the non-thermal DBD surface modification and the humidity-heat aging resistant performance in solar cell modules of FFC backsheet

    NASA Astrophysics Data System (ADS)

    Si, Qiong; Fei, Zhihuang; Jin, Jing; Qiu, Huayu; Zhang, Yuzheng

    2009-08-01

    The plasma generated by dielectric barrier discharge(DBD) with the atmosphere of lasting modifying materials, gives modification to the surfaces of FFC backsheet, which is formed by coating FFC (a tetra-fluoro based material with high content of fluorine) on the double-surfaces of polyester(PET). The research on the character of FFC backsheet before and after DBD modification is hold through a series analyzing ways, such as measuring the surface contact angles and surface energy of FFC backsheet with different plasma modification time and different DBD power density, comparing the preservation of surface energy of FFC backsheet with different storage medium and storage period, observing the surfaces of FFC backsheet through scanning electron microscope(SEM), making use of Fourier transform attenuated total reflectance infrared spectroscopy (ATR-FTIR) and X-ray photoelectron spectroscopy (XPS). Meanwhile, the soalr cell modules using FFC backsheet and other backsheets are tested under the condition of 85centigrade×85%RH to make comparison between FFC backsheet and other backsheets in various aspects, like the peel strength between backsheet and EVA and so on. All the tests show both the microscopic appearance and surface chemical composition of FFC backsheet is changed after the DBD plasma modification with the atmosphere of lasting modifying materials. After the DBD plasma modifications with a power density of 4.07W/cm2 and different modification time, the water contact angle for FFC backsheet surface is reduced from 82° to 38°. Comparing with other types of backsheets as the solar cell modules encapsulant materials, FFC backsheet has obvious advantage in humit-heat aging resistant performance of the peel strength with EVA and other respects.

  7. Humidity without Mystification

    ERIC Educational Resources Information Center

    Staver, Allen E.

    1977-01-01

    Demonstrates how a simple graph can be effectively used in teaching the concept, measurement, and use of humidity. Science activities for upper elementary, secondary, and higher education students are suggested and definitions of terms are presented. (Author/DB)

  8. Academics explore humidity's benefits.

    PubMed

    Mortimer, Dave

    2008-11-01

    The effects of humidification on hospital superbugs are being explored by some of the UK's top academics, in what Dave Mortimer, national sales manager for Vapac Humidity Control, explains are the UK's first such studies. PMID:19044148

  9. Acoustic Humidity Sensor

    NASA Technical Reports Server (NTRS)

    Shakkottai, Parthasarathy; Kwack, Eug Y.; Venkateshan, Shakkottai

    1990-01-01

    Industrial humidity sensor measures volume fraction of water in air via its effect on speed of sound. Only portion of sensor exposed to sensed atmosphere is pair of stainless-steel tubes, one containing dry air and other containing moist air. Counters measure intervals between reflected pulses. Sensor rugged enough for use in harsh environments like those used to control drying of paper in paper mills, where most humidity sensors do not survive.

  10. Heat or humidity, which triggers tree phenology?

    NASA Astrophysics Data System (ADS)

    Laube, Julia; Sparks, Tim H.; Estrella, Nicole; Menzel, Annette

    2014-05-01

    An overwhelming number of studies confirm that temperature is the main driver for phenological events such as leafing, flowering or fruit ripening, which was first discovered by Réaumur in 1735. Since then, several additional factors which influence onset dates have been identified, such as length of the chilling period, photoperiod, temperature of the previous autumn, nutrient availability, precipitation, sunshine and genetics (local adaptations). Those are supposed to capture some of the remaining, unexplained variance. But our ability to predict onset dates remains imprecise, and our understanding of how plants sense temperature is vague. From a climate chamber experiment on cuttings of 9 tree species we present evidence that air humidity is an important, but previously overlooked, factor influencing the spring phenology of trees. The date of median leaf unfolding was 7 days earlier at 90% relative humidity compared to 40% relative humidity. A second experiment with cuttings shows that water uptake by above-ground tissue might be involved in the phenological development of trees. A third climate chamber experiment suggests that winter dormancy and chilling might be linked to dehydration processes. Analysis of climate data from several meteorological stations across Germany proves that the increase in air humidity after winter is a reliable signal of spring, i.e. less variable or susceptible to reversal compared to temperature. Finally, an analysis of long-term phenology data reveals that absolute air humidity can even be used as a reliable predictor of leafing dates. Current experimental work tries to elucidate the involved foliar uptake processes by using deuterium oxide marked water and Raman spectroscopy. We propose a new framework, wherein plants' chilling requirements and frost tolerance might be attributed to desiccation processes, while spring development is linked to re-humidification of plant tissue. The influence of air humidity on the spring

  11. Absolute biological needs.

    PubMed

    McLeod, Stephen

    2014-07-01

    Absolute needs (as against instrumental needs) are independent of the ends, goals and purposes of personal agents. Against the view that the only needs are instrumental needs, David Wiggins and Garrett Thomson have defended absolute needs on the grounds that the verb 'need' has instrumental and absolute senses. While remaining neutral about it, this article does not adopt that approach. Instead, it suggests that there are absolute biological needs. The absolute nature of these needs is defended by appeal to: their objectivity (as against mind-dependence); the universality of the phenomenon of needing across the plant and animal kingdoms; the impossibility that biological needs depend wholly upon the exercise of the abilities characteristic of personal agency; the contention that the possession of biological needs is prior to the possession of the abilities characteristic of personal agency. Finally, three philosophical usages of 'normative' are distinguished. On two of these, to describe a phenomenon or claim as 'normative' is to describe it as value-dependent. A description of a phenomenon or claim as 'normative' in the third sense does not entail such value-dependency, though it leaves open the possibility that value depends upon the phenomenon or upon the truth of the claim. It is argued that while survival needs (or claims about them) may well be normative in this third sense, they are normative in neither of the first two. Thus, the idea of absolute need is not inherently normative in either of the first two senses. PMID:23586876

  12. Optical humidity sensor

    DOEpatents

    Tarvin, J.A.

    1987-02-10

    An optical dielectric humidity sensor is disclosed which includes a dielectric mirror having multiple alternating layers of two porous water-adsorbent dielectric materials with differing indices of refraction carried by a translucent substrate. A narrow-band polarized light source is positioned to direct light energy onto the mirror, and detectors are positioned to receive light energy transmitted through and reflected by the mirror. A ratiometer indicates humidity in the atmosphere which surrounds the dielectric mirror as a function of a ratio of light energies incident on the detectors. 2 figs.

  13. Optical humidity sensor

    DOEpatents

    Tarvin, Jeffrey A.

    1987-01-01

    An optical dielectric humidity sensor which includes a dielectric mirror having multiple alternating layers of two porous water-adsorbent dielectric materials with differing indices of refraction carried by a translucent substrate. A narrow-band polarized light source is positioned to direct light energy onto the mirror, and detectors are positioned to receive light energy transmitted through and reflected by the mirror. A ratiometer indicates humidity in the atmosphere which surrounds the dielectric mirror as a function of a ratio of light energies incident on the detectors.

  14. Modulation of Late Cretaceous and Cenozoic climate by variable drawdown of atmospheric pCO2 from weathering of basaltic provinces on continents drifting through the equatorial humid belt

    NASA Astrophysics Data System (ADS)

    Kent, D. V.; Muttoni, G.

    2012-09-01

    The small reservoir of carbon dioxide in the atmosphere (pCO2) that modulates climate through the greenhouse effect reflects a delicate balance between large fluxes of sources and sinks. The major long-term source of CO2 is global outgassing from sea-floor spreading, subduction, hotspot activity, and metamorphism; the ultimate sink is through weathering of continental silicates and deposition of carbonates. Most carbon cycle models are driven by changes in the source flux scaled to variable rates of ocean floor production. However, ocean floor production may not be distinguishable from being steady since 180 Ma. We evaluate potential changes in sources and sinks of CO2 for the past 120 Ma in a paleogeographic context. Our new calculations show that although decarbonation of pelagic sediments in Tethyan subduction likely contributed to generally high pCO2 levels from the Late Cretaceous until the Early Eocene, shutdown of Tethyan subduction with collision of India and Asia at the Early Eocene Climate Optimum at around 50 Ma was inadequate to account for the large and prolonged decrease in pCO2 that eventually allowed the growth of significant Antarctic ice sheets by around 34 Ma. Instead, variation in area of continental basaltic provinces in the equatorial humid belt (5° S-5° N) seems to be the dominant control on how much CO2 is retained in the atmosphere via the silicate weathering feedback. The arrival of the highly weatherable Deccan Traps in the equatorial humid belt at around 50 Ma was decisive in initiating the long-term slide to lower atmospheric pCO2, which was pushed further down by the emplacement of the 30 Ma Ethiopian Traps near the equator and the southerly tectonic extrusion of SE Asia, an arc terrane that presently is estimated to account for 1/4 of CO2 consumption from all basaltic provinces that account for ~1/3 of the total CO2 consumption by continental silicate weathering (Dessert et al., 2003). A negative climate-feedback mechanism that

  15. Modulation of Late Cretaceous and Cenozoic climate by variable drawdown of atmospheric pCO2 from weathering of basaltic provinces on continents drifting through the equatorial humid belt

    NASA Astrophysics Data System (ADS)

    Kent, D. V.; Muttoni, G.

    2013-03-01

    The small reservoir of carbon dioxide in the atmosphere (pCO2) that modulates climate through the greenhouse effect reflects a delicate balance between large fluxes of sources and sinks. The major long-term source of CO2 is global outgassing from sea-floor spreading, subduction, hotspot activity, and metamorphism; the ultimate sink is through weathering of continental silicates and deposition of carbonates. Most carbon cycle models are driven by changes in the source flux scaled to variable rates of ocean floor production, but ocean floor production may not be distinguishable from being steady since 180 Ma. We evaluate potential changes in sources and sinks of CO2 for the past 120 Ma in a paleogeographic context. Our new calculations show that decarbonation of pelagic sediments by Tethyan subduction contributed only modestly to generally high pCO2 levels from the Late Cretaceous until the early Eocene, and thus shutdown of this CO2 source with the collision of India and Asia at the early Eocene climate optimum at around 50 Ma was inadequate to account for the large and prolonged decrease in pCO2 that eventually allowed the growth of significant Antarctic ice sheets by around 34 Ma. Instead, variation in area of continental basalt terranes in the equatorial humid belt (5° S-5° N) seems to be a dominant factor controlling how much CO2 is retained in the atmosphere via the silicate weathering feedback. The arrival of the highly weatherable Deccan Traps in the equatorial humid belt at around 50 Ma was decisive in initiating the long-term slide to lower atmospheric pCO2, which was pushed further down by the emplacement of the 30 Ma Ethiopian Traps near the equator and the southerly tectonic extrusion of SE Asia, an arc terrane that presently is estimated to account for 1/4 of CO2 consumption from all basaltic provinces that account for ~1/3 of the total CO2 consumption by continental silicate weathering (Dessert et al., 2003). A negative climate-feedback mechanism

  16. Hands-on Humidity.

    ERIC Educational Resources Information Center

    Pankiewicz, Philip R.

    1992-01-01

    Presents five hands-on activities that allow students to detect, measure, reduce, and eliminate moisture. Students make a humidity detector and a hygrometer, examine the effects of moisture on different substances, calculate the percent of water in a given food, and examine the absorption potential of different desiccants. (MDH)

  17. Desiccant humidity control system

    NASA Technical Reports Server (NTRS)

    Amazeen, J. (Editor)

    1973-01-01

    A regenerable sorbent system was investigated for controlling the humidity and carbon dioxide concentration of the space shuttle cabin atmosphere. The sorbents considered for water and carbon dioxide removal were silica gel and molecular sieves. Bed optimization and preliminary system design are discussed along with system optimization studies and weight penalites.

  18. Association between absolute volumes of lung spared from low-dose irradiation and radiation-induced lung injury after intensity-modulated radiotherapy in lung cancer: a retrospective analysis.

    PubMed

    Chen, Jinmei; Hong, Jinsheng; Zou, Xi; Lv, Wenlong; Guo, Feibao; Hong, Hualan; Zhang, Weijian

    2015-11-01

    The aim of this study was to investigate the association between absolute volumes of lung spared from low-dose irradiation and radiation-induced lung injury (RILI) after intensity-modulated radiotherapy (IMRT) for lung cancer. The normal lung relative volumes receiving greater than 5, 10, 20 and 30 Gy (V5-30) mean lung dose (MLD), and absolute volumes spared from greater than 5, 10, 20 and 30 Gy (AVS5-30) for the bilateral and ipsilateral lungs of 83 patients were recorded. Any association of clinical factors and dose-volume parameters with Grade ≥2 RILI was analyzed. The median follow-up was 12.3 months; 18 (21.7%) cases of Grade 2 RILI, seven (8.4%) of Grade 3 and two (2.4%) of Grade 4 were observed. Univariate analysis revealed the located lobe of the primary tumor. V5, V10, V20, MLD of the ipsilateral lung, V5, V10, V20, V30 and MLD of the bilateral lung, and AVS5 and AVS10 of the ipsilateral lung were associated with Grade ≥2 RILI (P < 0.05). Multivariate analysis indicated AVS5 of the ipsilateral lung was prognostic for Grade ≥2 RILI (P = 0.010, OR = 0.272, 95% CI: 0.102-0.729). Receiver operating characteristic curves indicated Grade ≥2 RILI could be predicted using AVS5 of the ipsilateral lung (area under curve, 0.668; cutoff value, 564.9 cm(3); sensitivity, 60.7%; specificity, 70.4%). The incidence of Grade ≥2 RILI was significantly lower with AVS5 of the ipsilateral lung ≥564.9 cm(3) than with AVS5 < 564.9 cm(3) (P = 0.008). Low-dose irradiation relative volumes and MLD of the bilateral or ipsilateral lung were associated with Grade ≥2 RILI, and AVS5 of the ipsilateral lung was prognostic for Grade ≥2 RILI for lung cancer after IMRT. PMID:26454068

  19. The absolute path command

    SciTech Connect

    Moody, A.

    2012-05-11

    The ap command traveres all symlinks in a given file, directory, or executable name to identify the final absolute path. It can print just the final path, each intermediate link along with the symlink chan, and the permissions and ownership of each directory component in the final path. It has functionality similar to "which", except that it shows the final path instead of the first path. It is also similar to "pwd", but it can provide the absolute path to a relative directory from the current working directory.

  20. The absolute path command

    Energy Science and Technology Software Center (ESTSC)

    2012-05-11

    The ap command traveres all symlinks in a given file, directory, or executable name to identify the final absolute path. It can print just the final path, each intermediate link along with the symlink chan, and the permissions and ownership of each directory component in the final path. It has functionality similar to "which", except that it shows the final path instead of the first path. It is also similar to "pwd", but it canmore » provide the absolute path to a relative directory from the current working directory.« less

  1. Humidity: A review and primer on atmospheric moisture and human health.

    PubMed

    Davis, Robert E; McGregor, Glenn R; Enfield, Kyle B

    2016-01-01

    Research examining associations between weather and human health frequently includes the effects of atmospheric humidity. A large number of humidity variables have been developed for numerous purposes, but little guidance is available to health researchers regarding appropriate variable selection. We examine a suite of commonly used humidity variables and summarize both the medical and biometeorological literature on associations between humidity and human health. As an example of the importance of humidity variable selection, we correlate numerous hourly humidity variables to daily respiratory syncytial virus isolates in Singapore from 1992 to 1994. Most water-vapor mass based variables (specific humidity, absolute humidity, mixing ratio, dewpoint temperature, vapor pressure) exhibit comparable correlations. Variables that include a thermal component (relative humidity, dewpoint depression, saturation vapor pressure) exhibit strong diurnality and seasonality. Humidity variable selection must be dictated by the underlying research question. Despite being the most commonly used humidity variable, relative humidity should be used sparingly and avoided in cases when the proximity to saturation is not medically relevant. Care must be taken in averaging certain humidity variables daily or seasonally to avoid statistical biasing associated with variables that are inherently diurnal through their relationship to temperature. PMID:26599589

  2. Equations for the determination of humidity from dewpoint and psychrometric data

    NASA Technical Reports Server (NTRS)

    Parish, O. O.; Putnam, T. W.

    1977-01-01

    A general expression based on the Claperon-Clausius differential equation that relates saturation vapor pressure, absolute temperature, and the latent heat of transformation was derived that expresses saturation vapor pressure as a function of absolute temperature. This expression was then used to derive general expressions for vapor pressure, absolute humidity, and relative humidity as functions of either dewpoint and ambient temperature or psychrometric parameters. Constants for all general expressions were then evaluated to give specific expressions in both the international system of units and U.S. customary units for temperatures above and below freezing.

  3. Mars Science Laboratory (MSL) - First Results of Relative Humidity Observations

    NASA Astrophysics Data System (ADS)

    Genzer, Maria; Harri, Ari-Matti; Kemppinen, Osku; Gómez-Elvira, Javier; Renno, Nilton; Savijärvi, Hannu; Schmidt, Walter; Polkko, Jouni; Rodríquez-Manfredi, Jose Antonio; de la Torre Juárez, Manuel; Mischna, Michael; Martín-Torres, Javier; Haukka, Harri; Paz Zorzano-Mier, Maria; Rafkin, Scott; Paton, Mark; MSL Science Team

    2013-04-01

    The Mars Science laboratory (MSL) called Curiosity made a successful landing at Gale crater early August 2012. MSL has an environmental instrument package called the Rover Environmental Monitoring Station (REMS) as a part of its scientific payload. REMS comprises instrumentation for the observation of atmospheric pressure, temperature of the air, ground temperature, wind speed and direction, relative humidity, and UV measurements. The REMS instrument suite is described at length in [1]. We concentrate on describing the first results from the REMS relative humidity observations and comparison of the measurements with modeling results. The REMS humidity device is provided by the Finnish Meteorological Institute. It is based on polymeric capacitive humidity sensors developed by Vaisala Inc. The humidity device makes use of one transducer electronics section placed in the vicinity of the three (3) humidity sensor heads. The humidity device is mounted on the REMS boom 2 providing ventilation with the ambient atmosphere through a filter protecting the device from airborne dust. The absolute accuracy of the humidity device is temperature dependent, and is of the order of 2% at the temperature range of -30 to -10 °C, and of the order of 10% at the temperature range of -80 to -60 °C. This enables the investigations of atmospheric humidity variations of both diurnal and seasonal scale. The humidity device measurements will have a lag, when a step-wise change in humidity is taking place. This lag effect is increasing with decreasing temperature, and it is of the order of a few hours at the temperature of -75 °C. To compensate for the lag effect we used an algorithm developed by Mäkinen [2]. The humidity observations were validated after tedious efforts. This was needed to compensate for the artifacts of the transducer electronics. The compensation process includes an assumption that the relative humidity at Mars in the temperature range of 0 to -30 °C is about zero. The

  4. Molecular iodine absolute frequencies. Final report

    SciTech Connect

    Sansonetti, C.J.

    1990-06-25

    Fifty specified lines of {sup 127}I{sub 2} were studied by Doppler-free frequency modulation spectroscopy. For each line the classification of the molecular transition was determined, hyperfine components were identified, and one well-resolved component was selected for precise determination of its absolute frequency. In 3 cases, a nearby alternate line was selected for measurement because no well-resolved component was found for the specified line. Absolute frequency determinations were made with an estimated uncertainty of 1.1 MHz by locking a dye laser to the selected hyperfine component and measuring its wave number with a high-precision Fabry-Perot wavemeter. For each line results of the absolute measurement, the line classification, and a Doppler-free spectrum are given.

  5. Electronic Absolute Cartesian Autocollimator

    NASA Technical Reports Server (NTRS)

    Leviton, Douglas B.

    2006-01-01

    An electronic absolute Cartesian autocollimator performs the same basic optical function as does a conventional all-optical or a conventional electronic autocollimator but differs in the nature of its optical target and the manner in which the position of the image of the target is measured. The term absolute in the name of this apparatus reflects the nature of the position measurement, which, unlike in a conventional electronic autocollimator, is based absolutely on the position of the image rather than on an assumed proportionality between the position and the levels of processed analog electronic signals. The term Cartesian in the name of this apparatus reflects the nature of its optical target. Figure 1 depicts the electronic functional blocks of an electronic absolute Cartesian autocollimator along with its basic optical layout, which is the same as that of a conventional autocollimator. Referring first to the optical layout and functions only, this or any autocollimator is used to measure the compound angular deviation of a flat datum mirror with respect to the optical axis of the autocollimator itself. The optical components include an illuminated target, a beam splitter, an objective or collimating lens, and a viewer or detector (described in more detail below) at a viewing plane. The target and the viewing planes are focal planes of the lens. Target light reflected by the datum mirror is imaged on the viewing plane at unit magnification by the collimating lens. If the normal to the datum mirror is parallel to the optical axis of the autocollimator, then the target image is centered on the viewing plane. Any angular deviation of the normal from the optical axis manifests itself as a lateral displacement of the target image from the center. The magnitude of the displacement is proportional to the focal length and to the magnitude (assumed to be small) of the angular deviation. The direction of the displacement is perpendicular to the axis about which the

  6. A CMOS smart temperature and humidity sensor with combined readout.

    PubMed

    Eder, Clemens; Valente, Virgilio; Donaldson, Nick; Demosthenous, Andreas

    2014-01-01

    A fully-integrated complementary metal-oxide semiconductor (CMOS) sensor for combined temperature and humidity measurements is presented. The main purpose of the device is to monitor the hermeticity of micro-packages for implanted integrated circuits and to ensure their safe operation by monitoring the operating temperature and humidity on-chip. The smart sensor has two modes of operation, in which either the temperature or humidity is converted into a digital code representing a frequency ratio between two oscillators. This ratio is determined by the ratios of the timing capacitances and bias currents in both oscillators. The reference oscillator is biased by a current whose temperature dependency is complementary to the proportional to absolute temperature (PTAT) current. For the temperature measurement, this results in an exceptional normalized sensitivity of about 0.77%/°C at the accepted expense of reduced linearity. The humidity sensor is a capacitor, whose value varies linearly with relative humidity (RH) with a normalized sensitivity of 0.055%/% RH. For comparison, two versions of the humidity sensor with an area of either 0.2 mm2 or 1.2 mm2 were fabricated in a commercial 0.18 μm CMOS process. The on-chip readout electronics operate from a 5 V power supply and consume a current of approximately 85 µA. PMID:25230305

  7. A CMOS Smart Temperature and Humidity Sensor with Combined Readout

    PubMed Central

    Eder, Clemens; Valente, Virgilio; Donaldson, Nick; Demosthenous, Andreas

    2014-01-01

    A fully-integrated complementary metal-oxide semiconductor (CMOS) sensor for combined temperature and humidity measurements is presented. The main purpose of the device is to monitor the hermeticity of micro-packages for implanted integrated circuits and to ensure their safe operation by monitoring the operating temperature and humidity on-chip. The smart sensor has two modes of operation, in which either the temperature or humidity is converted into a digital code representing a frequency ratio between two oscillators. This ratio is determined by the ratios of the timing capacitances and bias currents in both oscillators. The reference oscillator is biased by a current whose temperature dependency is complementary to the proportional to absolute temperature (PTAT) current. For the temperature measurement, this results in an exceptional normalized sensitivity of about 0.77%/°C at the accepted expense of reduced linearity. The humidity sensor is a capacitor, whose value varies linearly with relative humidity (RH) with a normalized sensitivity of 0.055%/% RH. For comparison, two versions of the humidity sensor with an area of either 0.2 mm2 or 1.2 mm2 were fabricated in a commercial 0.18 μm CMOS process. The on-chip readout electronics operate from a 5 V power supply and consume a current of approximately 85 μA. PMID:25230305

  8. ABSOLUTE POLARIMETRY AT RHIC.

    SciTech Connect

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

    2007-09-10

    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.

  9. Crystal Microbalance Monitors Relative Humidity

    NASA Technical Reports Server (NTRS)

    Yang, L. C.

    1984-01-01

    Sensor monitors water evaporation in industrial drying processes. Measured adsorption isotherm for instrument essentially linear over entire range of relative humidity. Testing at each temperature setting less than half hour for full relative-humidity range, with estimated frequency response time less than 10 seconds. Used to measure relative humidity of ambient atmosphere near drying paper, food textile fabrics and pulp to optimize water-drying portion of processing cycle.

  10. System-in Package of Integrated Humidity Sensor Using CMOS-MEMS Technology.

    PubMed

    Lee, Sung Pil

    2015-10-01

    Temperature/humidity microchips with micropump were fabricated using a CMOS-MEMS process and combined with ZigBee modules to implement a sensor system in package (SIP) for a ubiquitous sensor network (USN) and/or a wireless communication system. The current of a diode temperature sensor to temperature and a normalized current of FET humidity sensor to relative humidity showed linear characteristics, respectively, and the use of the micropump has enabled a faster response. A wireless reception module using the same protocol as that in transmission systems processed the received data within 10 m and showed temperature and humidity values in the display. PMID:26726359

  11. Improving irrigation management for humid and sub-humid climates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This project includes studies led by both USDA-ARS and University of Missouri scientists, with a goal to develop solutions to broad water management problems with application to humid and sub-humid areas in the USA and the world. Our interdisciplinary team optimizes production systems for irrigated ...

  12. Improving irrigation management for humid and sub-humid climates

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This project includes studies led by both USDA-ARS and University of Missouri scientists, with a goal to develop solutions to broad water management problems with application to humid and sub-humid areas in the USA and the world. Our interdisciplinary team evaluates and optimizes production systems ...

  13. Implants as absolute anchorage.

    PubMed

    Rungcharassaeng, Kitichai; Kan, Joseph Y K; Caruso, Joseph M

    2005-11-01

    Anchorage control is essential for successful orthodontic treatment. Each tooth has its own anchorage potential as well as propensity to move when force is applied. When teeth are used as anchorage, the untoward movements of the anchoring units may result in the prolonged treatment time, and unpredictable or less-than-ideal outcome. To maximize tooth-related anchorage, techniques such as differential torque, placing roots into the cortex of the bone, the use of various intraoral devices and/or extraoral appliances have been implemented. Implants, as they are in direct contact with bone, do not possess a periodontal ligament. As a result, they do not move when orthodontic/orthopedic force is applied, and therefore can be used as "absolute anchorage." This article describes different types of implants that have been used as orthodontic anchorage. Their clinical applications and limitations are also discussed. PMID:16463910

  14. Absolute Equilibrium Entropy

    NASA Technical Reports Server (NTRS)

    Shebalin, John V.

    1997-01-01

    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.

  15. Humidity Graphs for All Seasons.

    ERIC Educational Resources Information Center

    Esmael, F.

    1982-01-01

    In a previous article in this journal (Vol. 17, p358, 1979), a wet-bulb depression table was recommended for two simple experiments to determine relative humidity. However, the use of a graph is suggested because it gives the relative humidity directly from the wet and dry bulb readings. (JN)

  16. Report Card on Humidity Control.

    ERIC Educational Resources Information Center

    Fischer, John C.; Bayer, Charlene

    2003-01-01

    Reports on an investigation of the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Standard 62-1999 on outdoor ventilation rates and space humidity levels for schools. Examined conventional cooling versus desiccant-based systems designed to control indoor humidity levels. Discusses the effectiveness of systems…

  17. Absolute neutrino mass measurements

    SciTech Connect

    Wolf, Joachim

    2011-10-06

    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.

  18. Absolute neutrino mass measurements

    NASA Astrophysics Data System (ADS)

    Wolf, Joachim

    2011-10-01

    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 (0v2β) searches, single β-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 β-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 (137Rh) 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&D phase. This paper reviews the present status of neutrino-mass measurements with cosmological data, 0v2β decay and single β-decay.

  19. Stomatal Response of Engelmann Spruce to Humidity, Light, and Water Stress 1

    PubMed Central

    Kaufmann, Merrill R.

    1976-01-01

    Stomatal response of Engelmann spruce (Picea engelmannii Engelm.) to environmental conditions was studied in the natural subalpine environment and under controlled laboratory conditions. Stomata of naturally occurring trees responded to the difference in absolute humidity from leaf to air. When foliage was exposed to full sunlight, stomatal conductance decreased as the absolute humidity difference increased. In the shade, where photosynthetically active radiation was 10% of that in full sunlight, stomatal closure at large absolute humidity differences was much more complete. No effect of soil or air temperatures on stomatal aperture was observed in the field, nor were differences among three contrasting sites detected. Under growth chamber conditions, stomata responded to photosynthetically active radiation, but conductances were influenced by leaf-to-air differences in absolute humidity. Leaf water potentials below - 15 bars resulted in lower conductances over a range of humidity and light conditions. Because net photosynthesis under shaded conditions in the natural environment must be very low, stomatal closure could result in considerable savings in water while having a minimum effect on net photosynthesis. PMID:16659594

  20. Gas and humidity sensing element

    SciTech Connect

    Komine, Y.; Sawada, T.

    1984-06-26

    A gas and humidity sensing element in a single integral structure made of a base plate of apatite ceramics, on which a particular metal oxide such as tin oxide, zinc oxide, or composite oxide of titanium and niobium is provided. The sensing element has a function of sensing gas and humidity with outstanding sensitivity to bad smell gas and alcoholic gas, in which the humidity is sensed and measured by variations in electrical resistance of the apatite ceramic base plate and the bad smell gas such as hydrogen sulfide, methyl mercaptan, etc. is sensed and measured by variations in electrical resistance of the metal oxide.

  1. Temperature, Humidity, And Polymer Aging

    NASA Technical Reports Server (NTRS)

    Cuddihy, Edward F.

    1988-01-01

    Report presents analysis of experimental data on electrical resistivity of polymer (polyvinyl butyral) as function of temperature and relative humidity. Resulting theoretical expression for electrical resistivity resembles generally accepted empirical law for the corrosion rate.

  2. Humidity testing of bleached holograms.

    PubMed

    Chenoweth, A J

    1971-04-01

    One of the proposed storage media for semipermanent optical stores is an array of bleached holograms fabricated on photographic plates. If a store utilizing this medium is to be operated in a field environment, the effect of humidity variation requires consideration. In this study holograms were made using either Burckhardt's potassium ferricyanide or Russo and Sottini's modified R-10 type bleach on Kodak 649F and Agfa 10E70 plates. Diffraction efficiency was measured as a function of relative humidity over the range 30-98%. For holograms fabricated and tested as described above it was found that relative humidity values above 75% caused a permanent loss in diffraction efficiency for potassium ferricyanide bleached plates; humidity above 90% produced a temporary loss in R-10 bleached plates. PMID:20094561

  3. Humidity sensing with doped polyaniline

    NASA Astrophysics Data System (ADS)

    Jain, Shilpa; Chakane, Sanjay D. S.; Bhoraskar, S. V.; Samui, A. B.; Krishnamurthy, V. N.

    2001-03-01

    Polyaniline (PANI) was doped with different dopants like camphosulphoric acid (CSA), diphenyl phosphate (DPPH), Sulphonic acid (S) and Maleic acid (MAC) by chemical method. The samples were prepared in the form of pellets as well as films. Polyaniline doped with Maleic acid was found to be mechanically and chemically stable as compared to other dopants and therefore the effect of humidity on conductivity was further investigated. Films prepared out of styrene buryl acrylate copolymer with different concentrations of PANI Maleic acid were used for sensing humidity ranging between 20% to 90% relative humidity. A maximum change in the conductivity of three to four orders of magnitude was obtained for the Maleic acid doped polyaniline pellet while two orders of magnitude change was obtained for the film samples over the range of humidity measured.

  4. Absolute Identification by Relative Judgment

    ERIC Educational Resources Information Center

    Stewart, Neil; Brown, Gordon D. A.; Chater, Nick

    2005-01-01

    In unidimensional absolute identification tasks, participants identify stimuli that vary along a single dimension. Performance is surprisingly poor compared with discrimination of the same stimuli. Existing models assume that identification is achieved using long-term representations of absolute magnitudes. The authors propose an alternative…

  5. Be Resolute about Absolute Value

    ERIC Educational Resources Information Center

    Kidd, Margaret L.

    2007-01-01

    This article explores how conceptualization of absolute value can start long before it is introduced. The manner in which absolute value is introduced to students in middle school has far-reaching consequences for their future mathematical understanding. It begins to lay the foundation for students' understanding of algebra, which can change…

  6. Humidity profiles over the ocean

    NASA Technical Reports Server (NTRS)

    Liu, W. T.; Tang, Wenqing; Niiler, Pearn P.

    1991-01-01

    The variabilities of atmospheric humidity profile over oceans from daily to interannual time scales were examined using 9 years of daily and semidaily radiosonde soundings at island stations extending from the Arctic to the South Pacific. The relative humidity profiles were found to have considerable temporal and geographic variabilities, contrary to the prevalent assumption. Principal component analysis on the profiles of specific humidity were used to examine the applicability of a relation between the surface-level humidity and the integrated water vapor; this relation has been used to estimate large-scale evaporation from satellite data. The first principal component was found to correlate almost perfectly with the integrated water vapor. The fractional variance represented by this mode increases with increasing period. It reaches approximately 90 percent at two weeks and decreases sharply, below one week, down to approximately 60 percent at the daily period. At low frequencies, the integrated water vapor appeared to be an adequate estimator of the humidity profile and the surface-level humidity. At periods shorter than a week, more than one independent estimator is needed.

  7. Simultaneous temperature and humidity measurements in a mechanical ventilator using an optical fibre sensor

    NASA Astrophysics Data System (ADS)

    Hernandez, F. U.; Correia, R.; Morgan, S. P.; Hayes-Gill, B.; Evans, D.; Sinha, R.; Norris, A.; Harvey, D.; Hardman, J. G.; Korposh, S.

    2016-05-01

    An optical fibre sensor for simultaneous temperature and humidity measurements consisting of one fibre Bragg grating (FBG) to measure temperature and a mesoporous film of bilayers of Poly(allylamine hydrochloride)(PAH) and silica (SiO2) nanoparticles deposited onto the tip of the same fibre to measure humidity is reported. The hygroscopic film was created using the layer-by-layer (LbL) method and the optical reflection spectra were measured up to a maximum of 23 bilayers. The temperature sensitivity of the FBG was 10 pm/°C while the sensitivity to humidity was (-1.4x10-12 W / %RH) using 23 bilayers. The developed sensor was tested in the mechanical ventilator and temperature and humidity of the delivered artificial air was simultaneously measured. Once calibrated, the optical fibre sensor has the potential to control the absolute humidity as an essential part of critical respiratory care.

  8. Humidity Sensors Printed on Recycled Paper and Cardboard

    PubMed Central

    Mraović, Matija; Muck, Tadeja; Pivar, Matej; Trontelj, Janez; Pleteršek, Anton

    2014-01-01

    Research, design, fabrication and results of various screen printed capacitive humidity sensors is presented in this paper. Two types of capacitive humidity sensors have been designed and fabricated via screen printing on recycled paper and cardboard, obtained from the regional paper and cardboard industry. As printing ink, commercially available silver nanoparticle-based conductive ink was used. A considerable amount of work has been devoted to the humidity measurement methods using paper as a dielectric material. Performances of different structures have been tested in a humidity chamber. Relative humidity in the chamber was varied in the range of 35%–80% relative humidity (RH) at a constant temperature of 23 °C. Parameters of interest were capacitance and conductance of each sensor material, as well as long term behaviour. Process reversibility has also been considered. The results obtained show a mainly logarithmic response of the paper sensors, with the only exception being cardboard-based sensors. Recycled paper-based sensors exhibit a change in value of three orders of magnitude, whereas cardboard-based sensors have a change in value of few 10s over the entire scope of relative humidity range (RH 35%–90%). Two different types of capacitor sensors have been investigated: lateral (comb) type sensors and modified, perforated flat plate type sensors. The objective of the present work was to identify the most important factors affecting the material performances with humidity, and to contribute to the development of a sensor system supported with a Radio Frequency Identification (RFID) chip directly on the material, for use in smart packaging applications. Therefore, the authors built a passive and a battery-supported wireless module based on SL900A smart sensory tag's IC to achieve UHF-RFID functionality with data logging capability. PMID:25072347

  9. Humidity sensors printed on recycled paper and cardboard.

    PubMed

    Mraović, Matija; Muck, Tadeja; Pivar, Matej; Trontelj, Janez; Pleteršek, Anton

    2014-01-01

    Research, design, fabrication and results of various screen printed capacitive humidity sensors is presented in this paper. Two types of capacitive humidity sensors have been designed and fabricated via screen printing on recycled paper and cardboard, obtained from the regional paper and cardboard industry. As printing ink, commercially available silver nanoparticle-based conductive ink was used. A considerable amount of work has been devoted to the humidity measurement methods using paper as a dielectric material. Performances of different structures have been tested in a humidity chamber. Relative humidity in the chamber was varied in the range of 35%-80% relative humidity (RH) at a constant temperature of 23 °C. Parameters of interest were capacitance and conductance of each sensor material, as well as long term behaviour. Process reversibility has also been considered. The results obtained show a mainly logarithmic response of the paper sensors, with the only exception being cardboard-based sensors. Recycled paper-based sensors exhibit a change in value of three orders of magnitude, whereas cardboard-based sensors have a change in value of few 10s over the entire scope of relative humidity range (RH 35%-90%). Two different types of capacitor sensors have been investigated: lateral (comb) type sensors and modified, perforated flat plate type sensors. The objective of the present work was to identify the most important factors affecting the material performances with humidity, and to contribute to the development of a sensor system supported with a Radio Frequency Identification (RFID) chip directly on the material, for use in smart packaging applications. Therefore, the authors built a passive and a battery-supported wireless module based on SL900A smart sensory tag's IC to achieve UHF-RFID functionality with data logging capability. PMID:25072347

  10. Modeling of the influence of humidity on H1N1 flu in China

    NASA Astrophysics Data System (ADS)

    PEI, Y.; Tian, H.; Xu, B.

    2015-12-01

    In 2009, a heavy Flu hit the whole world. It was caused by the virus H1N1. The influenza first broke out in Mexico in March and the United States in April, 2009. The World Health Organization (WHO) announced that the H1N1 influenza became pandemic, alert to a warning phase of six. By the end of 2011, 181302 H1N1 cases were reported in mainland China. To improve our understanding on the impact of environmental factors on the disease transmission, we constructed an SIR (Susceptible - Infectious - Recovered) model incorporating environmental factors. It was found that the absolute humidity was a dominant environmental factor. The study interpolated the humidity data monitored with 340 weather stations from 1951 to 2011 in mainland China. First, the break point of the trend for the absolutely humidity was detected by the BFAST (Break For Additive Season and Trend) method. Then, the SIR model with and without the absolutely humidity incorporated in the model was built and tested. Finally, the results with the two scenarios were compared. Results indicate that lower absolutely humidity may promote the transmission of the H1N1 cases. The calculated basic reproductive number ranges from 1.65 to 3.66 with a changing absolute humidity. This is consistent with the former study result with basic reproductive number ranging from 2.03 to 4.18. The average recovery duration was estimated to be 5.7 days. The average duration to get immunity from the influenza is 399.02 days. A risk map is also produced to illustrate the model results.

  11. Relative Humidity in Limited Streamer Tubes for Stanford Linear Accelerator Center's BaBar Detector

    SciTech Connect

    Lang, M.I.; Convery, M.; Menges, W.; /Queen Mary, U. of London

    2005-12-15

    The BABAR Detector at the Stanford Linear Accelerator Center studies the decay of B mesons created in e{sup +}e{sup -} collisions. The outermost layer of the detector, used to detect muons and neutral hadrons created during this process, is being upgraded from Resistive Plate Chambers (RPCs) to Limited Streamer Tubes (LSTs). The standard-size LST tube consists of eight cells, where a silver-plated wire runs down the center of each. A large potential difference is placed between the wires and ground. Gas flows through a series of modules connected with tubing, typically four. LSTs must be carefully tested before installation, as it will be extremely difficult to repair any damage once installed in the detector. In the testing process, the count rate in most modules showed was stable and consistent with cosmic ray rate over an approximately 500 V operating range between 5400 to 5900 V. The count in some modules, however, was shown to unexpectedly spike near the operation point. In general, the modules through which the gas first flows did not show this problem, but those further along the gas chain were much more likely to do so. The suggestion was that this spike was due to higher humidity in the modules furthest from the fresh, dry inflowing gas, and that the water molecules in more humid modules were adversely affecting the modules' performance. This project studied the effect of humidity in the modules, using a small capacitive humidity sensor (Honeywell). The sensor provided a humidity-dependent output voltage, as well as a temperature measurement from a thermistor. A full-size hygrometer (Panametrics) was used for testing and calibrating the Honeywell sensors. First the relative humidity of the air was measured. For the full calibration, a special gas-mixing setup was used, where relative humidity of the LST gas mixture could be varied from almost dry to almost fully saturated. With the sensor calibrated, a set of sensors was used to measure humidity vs. time

  12. Comparison of Single-Point and Continuous Sampling Methods for Estimating Residential Indoor Temperature and Humidity.

    PubMed

    Johnston, James D; Magnusson, Brianna M; Eggett, Dennis; Collingwood, Scott C; Bernhardt, Scott A

    2015-01-01

    Residential temperature and humidity are associated with multiple health effects. Studies commonly use single-point measures to estimate indoor temperature and humidity exposures, but there is little evidence to support this sampling strategy. This study evaluated the relationship between single-point and continuous monitoring of air temperature, apparent temperature, relative humidity, and absolute humidity over four exposure intervals (5-min, 30-min, 24-hr, and 12-days) in 9 northern Utah homes, from March-June 2012. Three homes were sampled twice, for a total of 12 observation periods. Continuous data-logged sampling was conducted in homes for 2-3 wks, and simultaneous single-point measures (n = 114) were collected using handheld thermo-hygrometers. Time-centered single-point measures were moderately correlated with short-term (30-min) data logger mean air temperature (r = 0.76, β = 0.74), apparent temperature (r = 0.79, β = 0.79), relative humidity (r = 0.70, β = 0.63), and absolute humidity (r = 0.80, β = 0.80). Data logger 12-day means were also moderately correlated with single-point air temperature (r = 0.64, β = 0.43) and apparent temperature (r = 0.64, β = 0.44), but were weakly correlated with single-point relative humidity (r = 0.53, β = 0.35) and absolute humidity (r = 0.52, β = 0.39). Of the single-point RH measures, 59 (51.8%) deviated more than ±5%, 21 (18.4%) deviated more than ±10%, and 6 (5.3%) deviated more than ±15% from data logger 12-day means. Where continuous indoor monitoring is not feasible, single-point sampling strategies should include multiple measures collected at prescribed time points based on local conditions. PMID:26030088

  13. A Humidity Generator for Temperatures up to 200 °C and Pressures up to 1.6 MPa

    NASA Astrophysics Data System (ADS)

    Vega-Maza, D.; Miller, W. W.; Ripple, D. C.; Scace, G. E.

    2012-09-01

    A new humidity generator that produces gas streams of known moisture content at temperatures from 85 °C to 200 °C, absolute pressures from 0.2 MPa to 1.6 MPa, and relative humidities from 10 % to 90 % has been developed. The generator produces a moist gas stream by injecting fixed-rate streams of dry gas and liquid water into a vaporizer, where the water evaporates into the gas. The gas stream passes into a re-entrant radio-frequency (RF) cavity, which serves as our reference hygrometer, and then a test chamber. The present standard uncertainty of the RF hygrometer is 0.6 %, limited by the uncertainty of literature values for the polarizability of water. Dry nitrogen gas purging the pressure transducer line also combines with the moist gas stream downstream of the test chamber and flows through one of a set of capillaries. Modulation of gas flow through the fixed flow impedance of the capillary gives a simple method for controlling pressure. Individual insulated, temperature-controlled aluminum ovens enclose each major component. A larger oven encloses these ovens and their connecting tubing. To minimize corrosion, critical components are constructed of high-nickel alloys. The small total volume (<1 L) and small flow rate (<0.5 L·min-1) reduce operational hazards from steam scalding or from gas explosion.

  14. Ultrahigh humidity sensitivity of graphene oxide

    PubMed Central

    Bi, Hengchang; Yin, Kuibo; Xie, Xiao; Ji, Jing; Wan, Shu; Sun, Litao; Terrones, Mauricio; Dresselhaus, Mildred S.

    2013-01-01

    Humidity sensors have been extensively used in various fields, and numerous problems are encountered when using humidity sensors, including low sensitivity, long response and recovery times, and narrow humidity detection ranges. Using graphene oxide (G-O) films as humidity sensing materials, we fabricate here a microscale capacitive humidity sensor. Compared with conventional capacitive humidity sensors, the G-O based humidity sensor has a sensitivity of up to 37800% which is more than 10 times higher than that of the best one among conventional sensors at 15%–95% relative humidity. Moreover, our humidity sensor shows a fast response time (less than 1/4 of that of the conventional one) and recovery time (less than 1/2 of that of the conventional one). Therefore, G-O appears to be an ideal material for constructing humidity sensors with ultrahigh sensitivity for widespread applications. PMID:24048093

  15. Ensuring minimal humidity levels in hermetic implant housings.

    PubMed

    Schuettler, Martin; Schatz, Andreas; Ordonez, Juan S; Stieglitz, Thomas

    2011-01-01

    The electronic circuitry of active implantable devices is commonly protected against the risk of water-induced corrosion by using gas-tight (hermetic) packages, preventing moisture from the host body to reach the electronics. However, when closing the package, one has to ensure that the packaged components do not contain moisture that could rise humidity inside the package to critical levels by outgassing. For our miniature metal/ceramic packages, we found a drying procedure of 120 °C at 180 mbar absolute pressure for one hour, followed by a dry helium purge sufficient to keep the relative humidity below 2.5% over a time span of 300 days at 80 °C, corresponding to over 15 years at 37 °C. The additional integration of a desiccant inside the package permits to keep the relative humidity below 0.1%, the detection limit of the integrated sensor. This sensor was selected based on an evaluation of 17 commercially available humidity sensors. PMID:22254800

  16. Ultrafast graphene oxide humidity sensors.

    PubMed

    Borini, Stefano; White, Richard; Wei, Di; Astley, Michael; Haque, Samiul; Spigone, Elisabetta; Harris, Nadine; Kivioja, Jani; Ryhänen, Tapani

    2013-12-23

    Sensors allow an electronic device to become a gateway between the digital and physical worlds, and sensor materials with unprecedented performance can create new applications and new avenues for user interaction. Graphene oxide can be exploited in humidity and temperature sensors with a number of convenient features such as flexibility, transparency and suitability for large-scale manufacturing. Here we show that the two-dimensional nature of graphene oxide and its superpermeability to water combine to enable humidity sensors with unprecedented response speed (∼30 ms response and recovery times). This opens the door to various applications, such as touchless user interfaces, which we demonstrate with a 'whistling' recognition analysis. PMID:24206232

  17. Absolute calibration of Landsat instruments using the moon.

    USGS Publications Warehouse

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

    1985-01-01

    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

  18. Stability of array spectroradiometers and their suitability for absolute calibrations

    NASA Astrophysics Data System (ADS)

    Nevas, Saulius; Teuber, Annette; Sperling, Armin; Lindemann, Matthias

    2012-04-01

    An investigation of the short- and long-term stability of various low-end and high-end array spectroradiometers is presented. Potentially weak points of array spectroradiometers with respect to their suitability for absolute calibrations are pointed out. The influence of ambient conditions on relevant instrumental characteristics and their temporal stability is discussed. It is shown that the temporal stability of some instruments can be significantly affected by high ambient humidity. Most important ambient temperature effects on instrument properties are also discussed.

  19. Effects of Humidity and Solution Viscosity on Electrospun Fiber Morphology

    PubMed Central

    Nezarati, Roya M.; Eifert, Michelle B.

    2013-01-01

    Electrospinning is a popular technique to fabricate tissue engineering scaffolds due to the exceptional tunability of fiber morphology that can be used to control scaffold mechanical properties, degradation rate, and cell behavior. Although the effects of modulating processing or solution parameters on fiber morphology have been extensively studied, there remains limited understanding of the impact of environmental parameters such as humidity. To address this gap, three polymers (poly(ethylene glycol) [PEG], polycaprolactone [PCL], and poly(carbonate urethane) [PCU]) were electrospun at a range of relative humidities (RH=5%–75%) and the resulting fiber architecture characterized with scanning electron microscopy. Low relative humidity (<50%) resulted in fiber breakage for all three polymers due to decreased electrostatic discharge from the jet. At high relative humidity (>50%), three distinct effects were observed based on individual polymer properties. An increase in fiber breakage and loss of fiber morphology occurred in the PEG system as a result of increased water absorption at high relative humidity. In contrast, surface pores on PCL fibers were observed and hypothesized to have formed via vapor-induced phase separation. Finally, decreased PCU fiber collection occurred at high humidity likely due to increased electrostatic discharge. These findings highlight that the effects of relative humidity on electrospun fiber morphology are dependent on polymer hydrophobicity, solvent miscibility with water, and solvent volatility. An additional study was conducted to highlight that small changes in molecular weight can strongly influence solution viscosity and resulting fiber morphology. We propose that solution viscosity rather than concentration is a more useful parameter to report in electrospinning methodology to enable reproduction of findings. In summary, this study further elucidates key mechanisms in electrospun fiber formation that can be utilized to

  20. Relative humidity from psychrometric data

    NASA Technical Reports Server (NTRS)

    Putnam, T. W.

    1976-01-01

    Analytical equation for computing relative humidity as function of wet bulb temperature, dry bulb temperature, and atmospheric pressure is suitable for use with calculator or computer. Analytical expressions may be useful for chemical process control systems and building environmental control systems.

  1. Absolute Position of Targets Measured Through a Chamber Window Using Lidar Metrology Systems

    NASA Technical Reports Server (NTRS)

    Kubalak, David; Hadjimichael, Theodore; Ohl, Raymond; Slotwinski, Anthony; Telfer, Randal; Hayden, Joseph

    2012-01-01

    Lidar is a useful tool for taking metrology measurements without the need for physical contact with the parts under test. Lidar instruments are aimed at a target using azimuth and elevation stages, then focus a beam of coherent, frequency modulated laser energy onto the target, such as the surface of a mechanical structure. Energy from the reflected beam is mixed with an optical reference signal that travels in a fiber path internal to the instrument, and the range to the target is calculated based on the difference in the frequency of the returned and reference signals. In cases when the parts are in extreme environments, additional steps need to be taken to separate the operator and lidar from that environment. A model has been developed that accurately reduces the lidar data to an absolute position and accounts for the three media in the testbed air, fused silica, and vacuum but the approach can be adapted for any environment or material. The accuracy of laser metrology measurements depends upon knowing the parameters of the media through which the measurement beam travels. Under normal conditions, this means knowledge of the temperature, pressure, and humidity of the air in the measurement volume. In the past, chamber windows have been used to separate the measuring device from the extreme environment within the chamber and still permit optical measurement, but, so far, only relative changes have been diagnosed. The ability to make accurate measurements through a window presents a challenge as there are a number of factors to consider. In the case of the lidar, the window will increase the time-of-flight of the laser beam causing a ranging error, and refract the direction of the beam causing angular positioning errors. In addition, differences in pressure, temperature, and humidity on each side of the window will cause slight atmospheric index changes and induce deformation and a refractive index gradient within the window. Also, since the window is a

  2. Absolute transition probabilities of phosphorus.

    NASA Technical Reports Server (NTRS)

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

    1971-01-01

    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.-

  3. Humidity sensing by carbon nanocones.

    PubMed

    Svåsand, Eldrid; Häberle, Patricio

    2014-05-01

    Carbon nano-structures, mainly nanotubes, have been explored in the past as sensing devices. In this report we have considered cones and discs (CNCs) subjected to acid treatment, dry oxidation and high temperature annealing, to study the modifications induced as they are used as sensing elements of varying relative humidity (RH). The relative humidity was varied in cycles of 30 min between 36% and 75%. Not strangely, the acid treated films displayed a much larger variation in resistance for the same difference in RH (16%). In the as-grown material, very small variations were detected among cycles under similar conditions. The changes induced in the sensors structures by the different preparation procedures were characterized by transmission electron microscopy (TEM) and Raman reflexion. These results were used to model their behaviour as RH sensors. PMID:24734591

  4. Comparisons of Upper Tropospheric Humidity Retrievals from TOVS and METEOSAT

    NASA Technical Reports Server (NTRS)

    Escoffier, C.; Bates, J.; Chedin, A.; Rossow, W. B.; Schmetz, J.

    1999-01-01

    Two different methods for retrieving Upper Tropospheric Humidities (UTH) from the TOVS (TIROS Operational Vertical Sounder) instruments aboard NOAA polar orbiting satellites are presented and compared. The first one, from the Environmental Technology Laboratory, computed by J. Bates and D. Jackson (hereafter BJ method), estimates UTH from a simplified radiative transfer analysis of the upper tropospheric infrared water vapor channel at wavelength measured by HIRS (6.3 micrometer). The second one results from a neural network analysis of the TOVS (HIRS and MSU) data developed at, the Laboratoire de Meteorologie Dynamique (hereafter the 3I (Improved Initialization Inversion) method). Although the two methods give very similar retrievals in temperate regions (30-60 N and S), an absolute bias up to 16% appears in the convective zone of the tropics. The two datasets have also been compared with UTH retrievals from infrared radiance measurements in the 6.3 micrometer channel from the geostationary satellite METEOSAT (hereafter MET method). The METEOSAT retrievals are systematically drier than the TOVS-based results by an absolute bias between 5 and 25%. Despite the biases, the spatial and temporal correlations are very good. The purpose of this study is to explain the deviations observed between the three datasets. The sensitivity of UTH to air temperature and humidity profiles is analysed as are the clouds effects. Overall, the comparison of the three retrievals gives an assessment of the current uncertainties in water vapor amounts in the upper troposphere as determined from NOAA and METEOSAT satellites.

  5. Humidity and Buildings. Technical Paper No. 188.

    ERIC Educational Resources Information Center

    Hutcheon, N. B.

    Modified and controlled relative humidity in buildings for certain occupancies is discussed. New criteria are used in determining the needs, desirability and problems associated with humidities in a building. Severe winter climate requires that special attention be given to the problems associated with increased indoor humidities during cold…

  6. A Humidity-Driven Prediction System for Influenza Outbreaks

    NASA Astrophysics Data System (ADS)

    Thrastarson, H. T.; Teixeira, J.

    2015-12-01

    Recent studies have highlighted the role of absolute (or specific) humidity conditions as a leading explanation for the seasonal behavior of influenza outbreaks in temperate regions. If the timing and intensity of seasonal influenza outbreaks can be forecast, this would be of great value for public health response efforts. We have developed and implemented a SIRS (Susceptible-Infectious-Recovered-Susceptible) type numerical prediction system that is driven by specific humidity to predict influenza outbreaks. For the humidity, we have explored using both satellite data from the AIRS (Atmospheric Infrared Sounder) instrument as well as ERA-Interim re-analysis data. We discuss the development, testing, sensitivities and limitations of the prediction system and show results for influenza outbreaks in the United States during the years 2010-2014 (modeled in retrospect). Comparisons are made with other existing prediction systems and available data for influenza outbreaks from Google Flu Trends and the CDC (Center for Disease Control), and the incorporation of these datasets into the forecasting system is discussed.

  7. Optomechanics for absolute rotation detection

    NASA Astrophysics Data System (ADS)

    Davuluri, Sankar

    2016-07-01

    In this article, we present an application of optomechanical cavity for the absolute rotation detection. The optomechanical cavity is arranged in a Michelson interferometer in such a way that the classical centrifugal force due to rotation changes the length of the optomechanical cavity. The change in the cavity length induces a shift in the frequency of the cavity mode. The phase shift corresponding to the frequency shift in the cavity mode is measured at the interferometer output to estimate the angular velocity of absolute rotation. We derived an analytic expression to estimate the minimum detectable rotation rate in our scheme for a given optomechanical cavity. Temperature dependence of the rotation detection sensitivity is studied.

  8. The Absolute Spectrum Polarimeter (ASP)

    NASA Technical Reports Server (NTRS)

    Kogut, A. J.

    2010-01-01

    The Absolute Spectrum Polarimeter (ASP) is an Explorer-class mission to map the absolute intensity and linear polarization of the cosmic microwave background and diffuse astrophysical foregrounds over the full sky from 30 GHz to 5 THz. The principal science goal is the detection and characterization of linear polarization from an inflationary epoch in the early universe, with tensor-to-scalar ratio r much greater than 1O(raised to the power of { -3}) and Compton distortion y < 10 (raised to the power of{-6}). We describe the ASP instrument and mission architecture needed to detect the signature of an inflationary epoch in the early universe using only 4 semiconductor bolometers.

  9. Absolute calibration of optical flats

    DOEpatents

    Sommargren, Gary E.

    2005-04-05

    The invention uses the phase shifting diffraction interferometer (PSDI) to provide a true point-by-point measurement of absolute flatness over the surface of optical flats. Beams exiting the fiber optics in a PSDI have perfect spherical wavefronts. The measurement beam is reflected from the optical flat and passed through an auxiliary optic to then be combined with the reference beam on a CCD. The combined beams include phase errors due to both the optic under test and the auxiliary optic. Standard phase extraction algorithms are used to calculate this combined phase error. The optical flat is then removed from the system and the measurement fiber is moved to recombine the two beams. The newly combined beams include only the phase errors due to the auxiliary optic. When the second phase measurement is subtracted from the first phase measurement, the absolute phase error of the optical flat is obtained.

  10. Stable and Selective Humidity Sensing Using Stacked Black Phosphorus Flakes.

    PubMed

    Yasaei, Poya; Behranginia, Amirhossein; Foroozan, Tara; Asadi, Mohammad; Kim, Kibum; Khalili-Araghi, Fatemeh; Salehi-Khojin, Amin

    2015-10-27

    Black phosphorus (BP) atomic layers are known to undergo chemical degradation in humid air. Yet in more robust configurations such as films, composites, and embedded structures, BP can potentially be utilized in a large number of practical applications. In this study, we explored the sensing characteristics of BP films and observed an ultrasensitive and selective response toward humid air with a trace-level detection capability and a very minor drift over time. Our experiments show that the drain current of the BP sensor increases by ∼4 orders of magnitude as the relative humidity (RH) varies from 10% to 85%, which ranks it among the highest ever reported values for humidity detection. The mechanistic studies indicate that the operation principle of the BP film sensors is based on the modulation in the leakage ionic current caused by autoionization of water molecules and ionic solvation of the phosphorus oxoacids produced on moist BP surfaces. Our stability tests reveal that the response of the BP film sensors remains nearly unchanged after prolonged exposures (up to 3 months) to ambient conditions. This study opens up the route for utilizing BP stacked films in many potential applications such as energy generation/storage systems, electrocatalysis, and chemical/biosensing. PMID:26401950

  11. Influence of humidity on radon and thoron exhalation rates from building materials.

    PubMed

    Janik, M; Omori, Y; Yonehara, H

    2014-10-24

    The contributions of radon and thoron from building materials to total radon (thoron) entry rates in dwellings range from almost zero to several percent. It is necessary to measure radon and thoron exhalation rates, among other things, to assess the radiological hazard to human health in a living environment. Brick and granite specimens were used to study the changes of these rates as a function of the relative and absolute humidities. Measurement results showed that radon and thoron exhalation rates change to humidity with the same trends as well as effective dose could be changed by the factor of 2 due to this. PMID:25464185

  12. Aging in humid granular media.

    PubMed

    Restagno, Frédéric; Ursini, Cécile; Gayvallet, Hervé; Charlaix, Elisabeth

    2002-08-01

    Aging behavior is an important effect in the friction properties of solid surfaces. In this paper we investigate the temporal evolution of the static properties of a granular medium by studying the aging over time of the maximum stability angle of submillimetric glass beads. We report the effect of several parameters on these aging properties, such as the wear on the beads, the stress during the resting period, and the humidity content of the atmosphere. Aging effects in an ethanol atmosphere are also studied. These experimental results are discussed at the end of the paper. PMID:12241167

  13. Measuring Humidity in Sealed Glass Encasements

    NASA Technical Reports Server (NTRS)

    West, James W.; Burkett, Cecil G.; Levine, Joel S.

    2005-01-01

    A technique has been devised for measuring the relative humidity levels in the protective helium/water vapor atmosphere in which the Declaration of Independence, the United States Constitution, and the Bill of Rights are encased behind glass panels on display at the National Archives in Washington, DC. The technique is noninvasive: it does not involve penetrating the encasements (thereby risking contamination or damage to the priceless documents) to acquire samples of the atmosphere. The technique could also be applied to similar glass encasements used to protect and display important documents and other precious objects in museums. The basic principle of the technique is straightforward: An encasement is maintained at its normal display or operating temperature (e.g., room temperature) while a portion of its glass front panel is chilled (see Figure 1) until condensed water droplets become visible on the inside of the panel. The relative humidity of the enclosed atmosphere can then be determined as a known function of the dew point, the temperature below which the droplets condense. Notwithstanding the straightforwardness of the basic principle, careful attention to detail is necessary to enable accurate determination of the dew point. In the initial application, the affected portion of the glass panel was cooled by contact with an aluminum plate that was cooled by a thermoelectric module, the exhaust heat of which was dissipated by a heat sink cooled by a fan. A thermocouple was used to measure the interior temperature of the aluminum plate, and six other thermocouples were used to measure the temperatures at six locations on the cooled outer surface of the glass panel (see Figure 2). Thermal grease was applied to the aluminum plate and the thermocouples to ensure close thermal contact. Power was supplied to the thermoelectric module in small increments, based on previous laboratory tests. A small flashlight and a magnifying glass were used to look for water

  14. VAB Temperature and Humidity Study

    NASA Technical Reports Server (NTRS)

    Lane, John E.; Youngquist, Robert C.; Muktarian, Edward; Nurge, Mark A.

    2014-01-01

    In 2012, 17 data loggers were placed in the VAB to measure temperature and humidity at 10-minute intervals over a one-year period. In 2013, the data loggers were replaced with an upgraded model and slight adjustments to their locations were made to reduce direct solar heating effects. The data acquired by the data loggers was compared to temperature data provided by three wind towers located around the building. It was found that the VAB acts as a large thermal filter, delaying and reducing the thermal oscillations occurring outside of the building. This filtering is typically more pronounced at higher locations in the building, probably because these locations have less thermal connection with the outside. We surmise that the lower elevations respond more to outside temperature variations because of air flow through the doors. Temperatures inside the VAB rarely exceed outdoor temperatures, only doing so when measurements are made directly on a surface with connection to the outside (such as a door or wall) or when solar radiation falls directly on the sensor. A thermal model is presented to yield approximate filter response times for various locations in the building. Appendix A contains historical thermal and humidity data from 1994 to 2009.

  15. Characterization of spacecraft humidity condensate

    NASA Technical Reports Server (NTRS)

    Muckle, Susan; Schultz, John R.; Sauer, Richard L.

    1994-01-01

    When construction of Space Station Freedom reaches the Permanent Manned Capability (PMC) stage, the Water Recovery and Management Subsystem will be fully operational such that (distilled) urine, spent hygiene water, and humidity condensate will be reclaimed to provide water of potable quality. The reclamation technologies currently baselined to process these waste waters include adsorption, ion exchange, catalytic oxidation, and disinfection. To ensure that the baseline technologies will be able to effectively remove those compounds presenting a health risk to the crew, the National Research Council has recommended that additional information be gathered on specific contaminants in waste waters representative of those to be encountered on the Space Station. With the application of new analytical methods and the analysis of waste water samples more representative of the Space Station environment, advances in the identification of the specific contaminants continue to be made. Efforts by the Water and Food Analytical Laboratory at JSC were successful in enlarging the database of contaminants in humidity condensate. These efforts have not only included the chemical characterization of condensate generated during ground-based studies, but most significantly the characterization of cabin and Spacelab condensate generated during Shuttle missions. The analytical results presented in this paper will be used to show how the composition of condensate varies amongst enclosed environments and thus the importance of collecting condensate from an environment close to that of the proposed Space Station. Although advances were made in the characterization of space condensate, complete characterization, particularly of the organics, requires further development of analytical methods.

  16. The AFGL absolute gravity program

    NASA Technical Reports Server (NTRS)

    Hammond, J. A.; Iliff, R. L.

    1978-01-01

    A brief discussion of the AFGL's (Air Force Geophysics Laboratory) program in absolute gravity is presented. Support of outside work and in-house studies relating to gravity instrumentation are discussed. A description of the current transportable system is included and the latest results are presented. These results show good agreement with measurements at the AFGL site by an Italian system. The accuracy obtained by the transportable apparatus is better than 0.1 microns sq sec 10 microgal and agreement with previous measurements is within the combined uncertainties of the measurements.

  17. Toward a New Generation of Photonic Humidity Sensors

    PubMed Central

    Kolpakov, Stanislav A.; Gordon, Neil T.; Mou, Chengbo; Zhou, Kaiming

    2014-01-01

    This review offers new perspectives on the subject and highlights an area in need of further research. It includes an analysis of current scientific literature mainly covering the last decade and examines the trends in the development of electronic, acoustic and optical-fiber humidity sensors over this period. The major findings indicate that a new generation of sensor technology based on optical fibers is emerging. The current trends suggest that electronic humidity sensors could soon be replaced by sensors that are based on photonic structures. Recent scientific advances are expected to allow dedicated systems to avoid the relatively high price of interrogation modules that is currently a major disadvantage of fiber-based sensors. PMID:24577524

  18. Relative Humidity Measurement Assurance Program Results

    NASA Technical Reports Server (NTRS)

    Cerezo, Miguel

    1993-01-01

    During the summer of 1992, the National Conference of Standards Laboratories sponsored a relative humidity measurement assurance program (RHMAP) whose purpose was to enable each participating center to assess the quality of relative humidity calibrations being performed by their respective standards laboratories. This paper presents the data which was submitted by the participants during the first round of the program and shows the multi-laboratory comparisons of the 20%, 50%, and 80% relative humidity meaurements performed.

  19. Trajectory Simulations of Upper Tropospheric Humidity

    NASA Technical Reports Server (NTRS)

    Dessler, A. E.; Schoeberl, M. R.; Sherwood, S. C.

    1999-01-01

    We present comparisons of simulations of upper tropospheric humidity at 215 and 146 hPa with satellite measurements. Our model uses diabatic trajectories to advect water vapor from an initial condition of 100% relative humidity to the final state. The model does not allow parcels' relative humidity to exceed 100%, and in this way crudely incorporates condensation. We find that this simple model does a good job of simulating the observations. Sensitivity studies suggest that one must have realistic wind velocities in order to accurately simulate the humidity distribution; microphysical parameterizations seem to be less important. Comparisions between simulations using UKMO and NCEP horizontal winds will be discussed.

  20. Technical Highlight: Evaluation of Humidity Control Options in Hot-Humid Climate Homes

    SciTech Connect

    none,

    2011-12-01

    This technical highlight describes NREL research to analyze the indoor relative humidity in three home types in the hot-humid climate zone, and examine the impacts of various dehumidification equipment and controls.

  1. Cosmology with negative absolute temperatures

    NASA Astrophysics Data System (ADS)

    Vieira, J. P. P.; Byrnes, Christian T.; Lewis, Antony

    2016-08-01

    Negative absolute temperatures (NAT) are an exotic thermodynamical consequence of quantum physics which has been known since the 1950's (having been achieved in the lab on a number of occasions). Recently, the work of Braun et al. [1] has rekindled interest in negative temperatures and hinted at a possibility of using NAT systems in the lab as dark energy analogues. This paper goes one step further, looking into the cosmological consequences of the existence of a NAT component in the Universe. NAT-dominated expanding Universes experience a borderline phantom expansion (w < ‑1) with no Big Rip, and their contracting counterparts are forced to bounce after the energy density becomes sufficiently large. Both scenarios might be used to solve horizon and flatness problems analogously to standard inflation and bouncing cosmologies. We discuss the difficulties in obtaining and ending a NAT-dominated epoch, and possible ways of obtaining density perturbations with an acceptable spectrum.

  2. Low-temperature oxidation of magnetite - a humidity sensitive process?

    NASA Astrophysics Data System (ADS)

    Appel, Erwin; Fang, Xiaomin; Herb, Christian; Hu, Shouyun

    2015-04-01

    Extensive multi-parameter palaeoclimate records were obtained from two long-term lacustrine archives at the Tibetan Plateau: the Qaidam basin (2.69-0.08 Ma) and Heqing basin (0.90-0.03 Ma). At present the region of the Qaidam site has an arid climate (<100 mm mean annual precipitation) while the Heqing site is located in the sub-tropical region with monsoonal rainfall. Magnetic properties play a prominent role for palaeoclimate interpretation in both records. Several parameters show a 100 kyr eccentricity cyclicity; in the Qaidam record also the Mid-Pleistocene Transition is seen. Both magnetic records are controlled by different absolute and relative contributions of magnetite and its altered (maghemitized) phases as well as hematite. Weathering conditions likely cause a systematic variation of magnetic mineralogy due to low-temperature oxidation (LTO). Maghemitization is well recognized as an alteration process in submarine basalts but about its relevance for climate-induced weathering in continental environments little is known. Various factors i.e., humidity, temperature, seasonality, duration of specific weathering conditions, and bacterial activity could be responsible for maghemitization (LTO) and transformation to hematite (or goethite) when a critical degree of LTO is reached. These factors may lead to a complex interplay, but one has to note that water acts as an electrolyte for Fe(II) to Fe(III) oxidation at the crystal surface and due to maghemitization-induced lattice shrinking a larger internal particle surface area becomes exposed to oxidation. We suggest that humidity is the most crucial driver for the two studied archives - for the following reasons: (1) The overall parameter variations and catchment conditions are well in agreement with an LTO scenario. (2) In the Qaidam record we observe a direct relationship of a humidity sensitive pollen Ratio with magnetic susceptibility (reflecting the degree of alteration by LTO). (3) In the Heqing record

  3. Boundaries for Biofilm Formation: Humidity and Temperature

    PubMed Central

    Else, Terry Ann; Pantle, Curtis R.; Amy, Penny S.

    2003-01-01

    Environmental conditions which define boundaries for biofilm production could provide useful ecological information for biofilm models. A practical use of defined conditions could be applied to the high-level nuclear waste repository at Yucca Mountain. Data for temperature and humidity conditions indicate that decreases in relative humidity or increased temperature severely affect biofilm formation on three candidate canister metals. PMID:12902302

  4. Fabrication and Evaluation of a Graphene Oxide-Based Capacitive Humidity Sensor.

    PubMed

    Feng, Jinfeng; Kang, Xiaoxu; Zuo, Qingyun; Yuan, Chao; Wang, Weijun; Zhao, Yuhang; Zhu, Limin; Lu, Hanwei; Chen, Juying

    2016-01-01

    In this study, a CMOS compatible capacitive humidity sensor structure was designed and fabricated on a 200 mm CMOS BEOL Line. A top Al interconnect layer was used as an electrode with a comb/serpent structure, and graphene oxide (GO) was used as sensing material. XRD analysis was done which shows that GO sensing material has a strong and sharp (002) peak at about 10.278°, whereas graphite has (002) peak at about 26°. Device level CV and IV curves were measured in mini-environments at different relative humidity (RH) level, and saturated salt solutions were used to build these mini-environments. To evaluate the potential value of GO material in humidity sensor applications, a prototype humidity sensor was designed and fabricated by integrating the sensor with a dedicated readout ASIC and display/calibration module. Measurements in different mini-environments show that the GO-based humidity sensor has higher sensitivity, faster recovery time and good linearity performance. Compared with a standard humidity sensor, the measured RH data of our prototype humidity sensor can match well that of the standard product. PMID:26938538

  5. Fabrication and Evaluation of a Graphene Oxide-Based Capacitive Humidity Sensor †

    PubMed Central

    Feng, Jinfeng; Kang, Xiaoxu; Zuo, Qingyun; Yuan, Chao; Wang, Weijun; Zhao, Yuhang; Zhu, Limin; Lu, Hanwei; Chen, Juying

    2016-01-01

    In this study, a CMOS compatible capacitive humidity sensor structure was designed and fabricated on a 200 mm CMOS BEOL Line. A top Al interconnect layer was used as an electrode with a comb/serpent structure, and graphene oxide (GO) was used as sensing material. XRD analysis was done which shows that GO sensing material has a strong and sharp (002) peak at about 10.278°, whereas graphite has (002) peak at about 26°. Device level CV and IV curves were measured in mini-environments at different relative humidity (RH) level, and saturated salt solutions were used to build these mini-environments. To evaluate the potential value of GO material in humidity sensor applications, a prototype humidity sensor was designed and fabricated by integrating the sensor with a dedicated readout ASIC and display/calibration module. Measurements in different mini-environments show that the GO-based humidity sensor has higher sensitivity, faster recovery time and good linearity performance. Compared with a standard humidity sensor, the measured RH data of our prototype humidity sensor can match well that of the standard product. PMID:26938538

  6. Absolute oral bioavailability of ciprofloxacin.

    PubMed

    Drusano, G L; Standiford, H C; Plaisance, K; Forrest, A; Leslie, J; Caldwell, J

    1986-09-01

    We evaluated the absolute bioavailability of ciprofloxacin, a new quinoline carboxylic acid, in 12 healthy male volunteers. Doses of 200 mg were given to each of the volunteers in a randomized, crossover manner 1 week apart orally and as a 10-min intravenous infusion. Half-lives (mean +/- standard deviation) for the intravenous and oral administration arms were 4.2 +/- 0.77 and 4.11 +/- 0.74 h, respectively. The serum clearance rate averaged 28.5 +/- 4.7 liters/h per 1.73 m2 for the intravenous administration arm. The renal clearance rate accounted for approximately 60% of the corresponding serum clearance rate and was 16.9 +/- 3.0 liters/h per 1.73 m2 for the intravenous arm and 17.0 +/- 2.86 liters/h per 1.73 m2 for the oral administration arm. Absorption was rapid, with peak concentrations in serum occurring at 0.71 +/- 0.15 h. Bioavailability, defined as the ratio of the area under the curve from 0 h to infinity for the oral to the intravenous dose, was 69 +/- 7%. We conclude that ciprofloxacin is rapidly absorbed and reliably bioavailable in these healthy volunteers. Further studies with ciprofloxacin should be undertaken in target patient populations under actual clinical circumstances. PMID:3777908

  7. Improving HST Pointing & Absolute Astrometry

    NASA Astrophysics Data System (ADS)

    Lallo, Matthew; Nelan, E.; Kimmer, E.; Cox, C.; Casertano, S.

    2007-05-01

    Accurate absolute astrometry is becoming increasingly important in an era of multi-mission archives and virtual observatories. Hubble Space Telescope's (HST's) Guidestar Catalog II (GSC2) has reduced coordinate error to around 0.25 arcsecond, a factor 2 or more compared with GSC1. With this reduced catalog error, special attention must be given to calibrate and maintain the Fine Guidance Sensors (FGSs) and Science Instruments (SIs) alignments in HST to a level well below this in order to ensure that the accuracy of science product's astrometry keywords and target positioning are limited only by the catalog errors. After HST Servicing Mission 4, such calibrations' improvement in "blind" pointing accuracy will allow for more efficient COS acquisitions. Multiple SIs and FGSs each have their own footprints in the spatially shared HST focal plane. It is the small changes over time in primarily the whole-body positions & orientations of these instruments & guiders relative to one another that is addressed by this work. We describe the HST Cycle 15 program CAL/OTA 11021 which, along with future variants of it, determines and maintains positions and orientations of the SIs and FGSs to better than 50 milli- arcseconds and 0.04 to 0.004 degrees of roll, putting errors associated with the alignment sufficiently below GSC2 errors. We present recent alignment results and assess their errors, illustrate trends, and describe where and how the observer sees benefit from these calibrations when using HST.

  8. Absolute Instability in Coupled-Cavity TWTs

    NASA Astrophysics Data System (ADS)

    Hung, D. M. H.; Rittersdorf, I. M.; Zhang, Peng; Lau, Y. Y.; Simon, D. H.; Gilgenbach, R. M.; Chernin, D.; Antonsen, T. M., Jr.

    2014-10-01

    This paper will present results of our analysis of absolute instability in a coupled-cavity traveling wave tube (TWT). The structure mode at the lower and upper band edges are respectively approximated by a hyperbola in the (omega, k) plane. When the Briggs-Bers criterion is applied, a threshold current for onset of absolute instability is observed at the upper band edge, but not the lower band edge. The nonexistence of absolute instability at the lower band edge is mathematically similar to the nonexistence of absolute instability that we recently demonstrated for a dielectric TWT. The existence of absolute instability at the upper band edge is mathematically similar to the existence of absolute instability in a gyroton traveling wave amplifier. These interesting observations will be discussed, and the practical implications will be explored. This work was supported by AFOSR, ONR, and L-3 Communications Electron Devices.

  9. Impacts of humidity and temperature on the performance of transparent conducting zinc oxide.

    SciTech Connect

    Granata, Jennifer E.; Yaklin, Melissa A.; Schneider, Duane Allen; Staiger, Chad Lynn; Norman, Kirsten

    2010-06-01

    The impact of humidity and temperature on a zinc oxide based transparent conducting oxide (TCO) was assessed under accelerated aging conditions. An in situ electroanalytical method was used to monitor the electrical properties for a conducting zinc oxide under controlled atmospheric (humidity, temperature and irradiation) conditions. A review of thin film photovoltaic (PV) literature has shown one major failure mode of cells/modules is associated with the ingress of water into modules in the field. Water contamination has been shown to degrade the performance of the TCO in addition to corroding interconnects and other conductive metals/materials associated with the module. Water ingress is particularly problematic in flexible thin film PV modules since traditional encapsulates such as poly(ethyl vinyl acetate) (EVA) have high water vapor transmission rates. The accelerated aging studies of the zinc oxide based TCOs will allow acceleration factors and kinetic parameters to be determined for reliability purposes.

  10. A Radiosonde Using a Humidity Sensor Array with a Platinum Resistance Heater and Multi-Sensor Data Fusion

    PubMed Central

    Shi, Yunbo; Luo, Yi; Zhao, Wenjie; Shang, Chunxue; Wang, Yadong; Chen, Yinsheng

    2013-01-01

    This paper describes the design and implementation of a radiosonde which can measure the meteorological temperature, humidity, pressure, and other atmospheric data. The system is composed of a CPU, microwave module, temperature sensor, pressure sensor and humidity sensor array. In order to effectively solve the humidity sensor condensation problem due to the low temperatures in the high altitude environment, a capacitive humidity sensor including four humidity sensors to collect meteorological humidity and a platinum resistance heater was developed using micro-electro-mechanical-system (MEMS) technology. A platinum resistance wire with 99.999% purity and 0.023 mm in diameter was used to obtain the meteorological temperature. A multi-sensor data fusion technique was applied to process the atmospheric data. Static and dynamic experimental results show that the designed humidity sensor with platinum resistance heater can effectively tackle the sensor condensation problem, shorten response times and enhance sensitivity. The humidity sensor array can improve measurement accuracy and obtain a reliable initial meteorological humidity data, while the multi-sensor data fusion technique eliminates the uncertainty in the measurement. The radiosonde can accurately reflect the meteorological changes. PMID:23857263

  11. A radiosonde using a humidity sensor array with a platinum resistance heater and multi-sensor data fusion.

    PubMed

    Shi, Yunbo; Luo, Yi; Zhao, Wenjie; Shang, Chunxue; Wang, Yadong; Chen, Yinsheng

    2013-01-01

    This paper describes the design and implementation of a radiosonde which can measure the meteorological temperature, humidity, pressure, and other atmospheric data. The system is composed of a CPU, microwave module, temperature sensor, pressure sensor and humidity sensor array. In order to effectively solve the humidity sensor condensation problem due to the low temperatures in the high altitude environment, a capacitive humidity sensor including four humidity sensors to collect meteorological humidity and a platinum resistance heater was developed using micro-electro-mechanical-system (MEMS) technology. A platinum resistance wire with 99.999% purity and 0.023 mm in diameter was used to obtain the meteorological temperature. A multi-sensor data fusion technique was applied to process the atmospheric data. Static and dynamic experimental results show that the designed humidity sensor with platinum resistance heater can effectively tackle the sensor condensation problem, shorten response times and enhance sensitivity. The humidity sensor array can improve measurement accuracy and obtain a reliable initial meteorological humidity data, while the multi-sensor data fusion technique eliminates the uncertainty in the measurement. The radiosonde can accurately reflect the meteorological changes. PMID:23857263

  12. Absolute negative mobility of interacting Brownian particles

    NASA Astrophysics Data System (ADS)

    Ou, Ya-li; Hu, Cai-tian; Wu, Jian-chun; Ai, Bao-quan

    2015-12-01

    Transport of interacting Brownian particles in a periodic potential is investigated in the presence of an ac force and a dc force. From Brownian dynamic simulations, we find that both the interaction between particles and the thermal fluctuations play key roles in the absolute negative mobility (the particle noisily moves backwards against a small constant bias). When no the interaction acts, there is only one region where the absolute negative mobility occurs. In the presence of the interaction, the absolute negative mobility may appear in multiple regions. The weak interaction can be helpful for the absolute negative mobility, while the strong interaction has a destructive impact on it.

  13. Synthesis, characterization, and humidity sensing of metallophtalocyanines

    NASA Astrophysics Data System (ADS)

    Chakane, Sanjay D. S.; Jain, Shilpa; Bhoraskar, S. V.

    2001-03-01

    Metallophthalocyanines synthesized for different metals such as Ni, Cr, Ag, Mg, Cu, Cd, Al, etc by chemical methods were characterized with FTIR, UV etc. Sensing of humidity and different gases such as Nox, H2, O2, CO2, N2, ammonia, alcohol vapours etc were checked with 2-probe technique with monitoring change in resistance change. These samples have excellent stability against heat, light, air, and hence it has considerable attention for environmentally stable gas sensor. The electrical property of these samples were investigated at room temperature and at normal atmospheric pressure from low to 98% relative Humidity. It was observed that these samples shows good response and recovery for humidity sensing.

  14. Absolute determination of local tropospheric OH concentrations

    NASA Technical Reports Server (NTRS)

    Armerding, Wolfgang; Comes, Franz-Josef

    1994-01-01

    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.

  15. Inequalities, Absolute Value, and Logical Connectives.

    ERIC Educational Resources Information Center

    Parish, Charles R.

    1992-01-01

    Presents an approach to the concept of absolute value that alleviates students' problems with the traditional definition and the use of logical connectives in solving related problems. Uses a model that maps numbers from a horizontal number line to a vertical ray originating from the origin. Provides examples solving absolute value equations and…

  16. Monolithically integrated absolute frequency comb laser system

    DOEpatents

    Wanke, Michael C.

    2016-07-12

    Rather than down-convert optical frequencies, a QCL laser system directly generates a THz frequency comb in a compact monolithically integrated chip that can be locked to an absolute frequency without the need of a frequency-comb synthesizer. The monolithic, absolute frequency comb can provide a THz frequency reference and tool for high-resolution broad band spectroscopy.

  17. Introducing the Mean Absolute Deviation "Effect" Size

    ERIC Educational Resources Information Center

    Gorard, Stephen

    2015-01-01

    This paper revisits the use of effect sizes in the analysis of experimental and similar results, and reminds readers of the relative advantages of the mean absolute deviation as a measure of variation, as opposed to the more complex standard deviation. The mean absolute deviation is easier to use and understand, and more tolerant of extreme…

  18. Investigating Absolute Value: A Real World Application

    ERIC Educational Resources Information Center

    Kidd, Margaret; Pagni, David

    2009-01-01

    Making connections between various representations is important in mathematics. In this article, the authors discuss the numeric, algebraic, and graphical representations of sums of absolute values of linear functions. The initial explanations are accessible to all students who have experience graphing and who understand that absolute value simply…

  19. Absolute Income, Relative Income, and Happiness

    ERIC Educational Resources Information Center

    Ball, Richard; Chernova, Kateryna

    2008-01-01

    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…

  20. Surface Temperature Humidity Reference System Handbook - November 2005

    SciTech Connect

    MT Ritsche

    2005-11-30

    The Surface Temperature and Humidity Reference (SURTHREF) system is intended to provide accurate reference values of ambient temperature and relative humidity for comparison with radiosonde prelaunch values.

  1. Method of differential-phase/absolute-amplitude QAM

    DOEpatents

    Dimsdle, Jeffrey William

    2007-07-03

    A method of quadrature amplitude modulation involving encoding phase differentially and amplitude absolutely, allowing for a high data rate and spectral efficiency in data transmission and other communication applications, and allowing for amplitude scaling to facilitate data recovery; amplitude scale tracking to track-out rapid and severe scale variations and facilitate successful demodulation and data retrieval; 2.sup.N power carrier recovery; incoherent demodulation where coherent carrier recovery is not possible or practical due to signal degradation; coherent demodulation; multipath equalization to equalize frequency dependent multipath; and demodulation filtering.

  2. Method of differential-phase/absolute-amplitude QAM

    DOEpatents

    Dimsdle, Jeffrey William

    2008-10-21

    A method of quadrature amplitude modulation involving encoding phase differentially and amplitude absolutely, allowing for a high data rate and spectral efficiency in data transmission and other communication applications, and allowing for amplitude scaling to facilitate data recovery; amplitude scale tracking to track-out rapid and severe scale variations and facilitate successful demodulation and data retrieval; 2.sup.N power carrier recovery; incoherent demodulation where coherent carrier recovery is not possible or practical due to signal degradation; coherent demodulation; multipath equalization to equalize frequency dependent multipath; and demodulation filtering.

  3. Method of differential-phase/absolute-amplitude QAM

    DOEpatents

    Dimsdle, Jeffrey William

    2007-07-17

    A method of quadrature amplitude modulation involving encoding phase differentially and amplitude absolutely, allowing for a high data rate and spectral efficiency in data transmission and other communication applications, and allowing for amplitude scaling to facilitate data recovery; amplitude scale tracking to track-out rapid and severe scale variations and facilitate successful demodulation and data retrieval; 2.sup.N power carrier recovery; incoherent demodulation where coherent carrier recovery is not possible or practical due to signal degradation; coherent demodulation; multipath equalization to equalize frequency dependent multipath; and demodulation filtering.

  4. Method of differential-phase/absolute-amplitude QAM

    DOEpatents

    Dimsdle, Jeffrey William

    2007-10-02

    A method of quadrature amplitude modulation involving encoding phase differentially and amplitude absolutely, allowing for a high data rate and spectral efficiency in data transmission and other communication applications, and allowing for amplitude scaling to facilitate data recovery; amplitude scale tracking to track-out rapid and severe scale variations and facilitate successful demodulation and data retrieval; 2.sup.N power carrier recovery; incoherent demodulation where coherent carrier recovery is not possible or practical due to signal degradation; coherent demodulation; multipath equalization to equalize frequency dependent multipath; and demodulation filtering.

  5. Method of differential-phase/absolute-amplitude QAM

    DOEpatents

    Dimsdle, Jeffrey William

    2009-09-01

    A method of quadrature amplitude modulation involving encoding phase differentially and amplitude absolutely, allowing for a high data rate and spectral efficiency in data transmission and other communication applications, and allowing for amplitude scaling to facilitate data recovery; amplitude scale tracking to track-out rapid and severe scale variations and facilitate successful demodulation and data retrieval; 2.sup.N power carrier recovery; incoherent demodulation where coherent carrier recovery is not possible or practical due to signal degradation; coherent demodulation; multipath equalization to equalize frequency dependent multipath; and demodulation filtering.

  6. Absolute instability of the Gaussian wake profile

    NASA Technical Reports Server (NTRS)

    Hultgren, Lennart S.; Aggarwal, Arun K.

    1987-01-01

    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.

  7. Apparatus and methods for humidity control

    NASA Technical Reports Server (NTRS)

    Dinauer, William R. (Inventor); Otis, David R. (Inventor); El-Wakil, Mohamed M. (Inventor); Vignali, John C. (Inventor); Macaulay, Philip D. (Inventor)

    1994-01-01

    Apparatus is provided which controls humidity in a gas. The apparatus employs a porous interface that is preferably a manifolded array of stainless steel tubes through whose porous surface water vapor can pass. One side of the porous interface is in contact with water and the opposing side is in contact with gas whose humidity is being controlled. Water vapor is emitted from the porous surface of the tubing into the gas when the gas is being humidified, and water vapor is removed from the gas through the porous surfaces when the gas is being dehumidified. The temperature of the porous interface relative to the gas temperature determines whether humidification or dehumidification is being carried out. The humidity in the gas is sensed and compared to the set point humidity. The water temperature, and consequently the porous interface temperature, are automatically controlled in response to changes in the gas humidity level above or below the set point. Any deviation from the set point humidity is thus corrected.

  8. How factoring in humidity adds value

    SciTech Connect

    Berlin, G. )

    1994-09-01

    Humidity plays a major role in health, comfort, and production. This article is a brief overview of the technologies available and a detailed explanation of how to calculate humidification loads. The problems caused by dry air vary from one building to another and from one area to another. But basically, there are three major problem types: static electricity, poor moisture stability, health and comfort problems. In today's business offices, static electricity can disrupt operations and increase operating costs. In printing facilities, low humidity causes poor ink registration. Also, sheets of paper stick together and jam machines, wasting time and paper. In computer rooms and data processing areas, dry air leads to static electric discharges that cause circuit board failure, dust buildup on heads, and storage tape breakage. Moisture stability impacts industrial processes and the materials they use. In many cases, product and material deterioration is directly related to moisture fluctuations and lack of humidity control. Books, antiques, paper, wood and wood products, and fruits and vegetables are a few items that can be ruined by low or changing humidity. The health impact of low humidity shows up in dry nasal and thread membranes, dry and itchy skin, and irritated eyes. For employees, this means greater susceptibility to colds and other viral infections. The results is higher absenteeism when humidity is low, which translates into lost productivity and profits.

  9. Insect hygroreceptor responses to continuous changes in humidity and air pressure

    PubMed Central

    Tichy, H.; Kallina, W.

    2011-01-01

    The most favored model of humidity transduction views the cuticular wall of insect hygroreceptive sensilla as a hygromechanical transducer. Hygroscopic swelling or shrinking alters the geometry of the wall, deforming the dendritic membranes of the moist and dry cells. The small size the sensilla and their position surrounded by elevated structures creates technical difficulties to mechanically stimulate them by direct contact. The present study investigated hygroreceptors on the antennae of the cockroach and the stick insect. Accurately controlled, homogeneous mechanical input was delivered by modulating air pressure. Both the moist and dry cells responded not only to changes in air pressure, but also in the opposite direction, as observed during changes in air humidity. The moist-cell’s excitatory response to increasing humidity and increasing air pressure implies that swelling of the hygroscopic cuticle compresses the dendrites, and the dry-cell’s excitatory response to decreasing humidity and decreasing air pressure implies that shrinking of the hygroscopic cuticle expands the dendrites. The moist and dry cells of the stick insect are more sensitive to pressure changes than those of the cockroach, but the responses to air pressure are generally weaker than to humidity. Therefore, the hygroreceptive sensilla differ in their physical properties and constitutions. Furthermore, the mechanical parameters associated with homogeneous changes in air pressure on the sensillum surface can only partially account for the responses of the moist and dry cells of both species to humidity stimulation. PMID:20375249

  10. Insect hygroreceptor responses to continuous changes in humidity and air pressure.

    PubMed

    Tichy, H; Kallina, W

    2010-06-01

    The most favored model of humidity transduction views the cuticular wall of insect hygroreceptive sensilla as a hygromechanical transducer. Hygroscopic swelling or shrinking alters the geometry of the wall, deforming the dendritic membranes of the moist and dry cells. The small size the sensilla and their position surrounded by elevated structures creates technical difficulties to mechanically stimulate them by direct contact. The present study investigated hygroreceptors on the antennae of the cockroach and the stick insect. Accurately controlled, homogeneous mechanical input was delivered by modulating air pressure. Both the moist and dry cells responded not only to changes in air pressure but also in the opposite direction, as observed during changes in air humidity. The moist cell's excitatory response to increasing humidity and increasing air pressure implies that swelling of the hygroscopic cuticle compresses the dendrites, and the dry cell's excitatory response to decreasing humidity and decreasing air pressure implies that shrinking of the hygroscopic cuticle expands the dendrites. The moist and dry cells of the stick insect are more sensitive to pressure changes than those of the cockroach, but the responses to air pressure are generally weaker than to humidity. Therefore the hygroreceptive sensilla differ in their physical properties and constitutions. Furthermore, the mechanical parameters associated with homogeneous changes in air pressure on the sensillum surface can only partially account for the responses of the moist and dry cells of both species to humidity stimulation. PMID:20375249

  11. The Russian National Standard of Gases Humidity and Traceability System of Humidity Measurements

    NASA Astrophysics Data System (ADS)

    Dubovikov, N. I.; Podmurnaya, O. A.; Skryabikov, N. P.; Sokov, I. A.; Vinge, A. F.

    2016-05-01

    The Russian national humidity standard of gases has been modernized in order to increase the number of reproducible quantities of humidity (relative humidity, dew/frost-point temperature, mole fraction) and to extend the humidity and operating temperature ranges. The basis of the standard comprises two humidity generators with operating temperature ranges from 5 ^{circ }hbox {C} to 90 ^{circ }hbox {C} and from -60 ^{circ }hbox {C} to 15 ^{circ }hbox {C}. The common working range (from 5 ^{circ }hbox {C} to 15 ^{circ }hbox {C}) allows comparison of the generators. The generators use the two-pressure method to generate humid gas defined in terms of the relative humidity (from 5 %rh to 98 %rh at temperatures from 90 ^{circ }hbox {C} to -60 ^{circ }hbox {C}) and the one-pressure (or phase equilibrium) method to generate humid gas defined in terms of the vapor mole fraction (from 0.6 ppm to 700× 103 ppm) and dew/frost-point temperature (from -79 ^{circ }hbox {C} to 90 ^{circ }hbox {C}). The expanded uncertainty in the relative humidity is no more than 0.2 %rh, no more than 1.2 % in the vapor mole fraction, and no more than 0.12 ^{circ }hbox {C} in the dew/frost-point temperature. The ordinary hygrometers are traceable to the national primary standard in accordance with the state hierarchical chain for measuring means of gas humidity. The state hierarchical chain consists of three branches for means of measurements: (a) mole fraction, (b) dew/frost-point temperature, and (c) relative humidity with each branch represented as the scheme: primary standard-secondary standard-working standard-ordinary hygrometer. Calibration and verification of working standards and ordinary hygrometers, and their traceability to the primary standard use methods of (i) direct measurements, (ii) direct comparison, or (iii) comparison with a comparator.

  12. Absolute optical instruments without spherical symmetry

    NASA Astrophysics Data System (ADS)

    Tyc, Tomáš; Dao, H. L.; Danner, Aaron J.

    2015-11-01

    Until now, the known set of absolute optical instruments has been limited to those containing high levels of symmetry. Here, we demonstrate a method of mathematically constructing refractive index profiles that result in asymmetric absolute optical instruments. The method is based on the analogy between geometrical optics and classical mechanics and employs Lagrangians that separate in Cartesian coordinates. In addition, our method can be used to construct the index profiles of most previously known absolute optical instruments, as well as infinitely many different ones.

  13. Humidity effects on wire insulation breakdown strength.

    SciTech Connect

    Appelhans, Leah

    2013-08-01

    Methods for the testing of the dielectric breakdown strength of insulation on metal wires under variable humidity conditions were developed. Two methods, an ASTM method and the twisted pair method, were compared to determine if the twisted pair method could be used for determination of breakdown strength under variable humidity conditions. It was concluded that, although there were small differences in outcomes between the two testing methods, the non-standard method (twisted pair) would be appropriate to use for further testing of the effects of humidity on breakdown performance. The dielectric breakdown strength of 34G copper wire insulated with double layer Poly-Thermaleze/Polyamide-imide insulation was measured using the twisted pair method under a variety of relative humidity (RH) conditions and exposure times. Humidity at 50% RH and below was not found to affect the dielectric breakdown strength. At 80% RH the dielectric breakdown strength was significantly diminished. No effect for exposure time up to 140 hours was observed at 50 or 80%RH.

  14. 40 CFR 91.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air humidity measurement... Provisions § 91.310 Engine intake air humidity measurement. This section refers to engines which are supplied... air, the ambient testcell humidity measurement may be used. (a) Humidity conditioned air supply....

  15. 40 CFR 91.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air humidity measurement... Provisions § 91.310 Engine intake air humidity measurement. This section refers to engines which are supplied... air, the ambient testcell humidity measurement may be used. (a) Humidity conditioned air supply....

  16. 40 CFR 91.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air humidity measurement... Provisions § 91.310 Engine intake air humidity measurement. This section refers to engines which are supplied... air, the ambient testcell humidity measurement may be used. (a) Humidity conditioned air supply....

  17. 40 CFR 91.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air humidity measurement... Provisions § 91.310 Engine intake air humidity measurement. This section refers to engines which are supplied... air, the ambient testcell humidity measurement may be used. (a) Humidity conditioned air supply....

  18. 40 CFR 91.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air humidity measurement... Provisions § 91.310 Engine intake air humidity measurement. This section refers to engines which are supplied... air, the ambient testcell humidity measurement may be used. (a) Humidity conditioned air supply....

  19. Absolute dose calculations for Monte Carlo simulations of radiotherapy beams.

    PubMed

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

    2005-07-21

    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 x 10 cm2 field of a 6 MV photon beam, 1 MU corresponds, in our model, to 8.129 x 10(13) +/- 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. PMID:16177516

  20. Absolute dose calculations for Monte Carlo simulations of radiotherapy beams

    NASA Astrophysics Data System (ADS)

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

    2005-07-01

    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.

  1. Absolute magnitudes of trans-neptunian objects

    NASA Astrophysics Data System (ADS)

    Duffard, R.; Alvarez-candal, A.; Pinilla-Alonso, N.; Ortiz, J. L.; Morales, N.; Santos-Sanz, P.; Thirouin, A.

    2015-10-01

    Accurate measurements of diameters of trans- Neptunian objects are extremely complicated to obtain. Radiomatric techniques applied to thermal measurements can provide good results, but precise absolute magnitudes are needed to constrain diameters and albedos. Our objective is to measure accurate absolute magnitudes for a sample of trans- Neptunian objects, many of which have been observed, and modelled, by the "TNOs are cool" team, one of Herschel Space Observatory key projects grantes with ~ 400 hours of observing time. We observed 56 objects in filters V and R, if possible. These data, along with data available in the literature, was used to obtain phase curves and to measure absolute magnitudes by assuming a linear trend of the phase curves and considering magnitude variability due to rotational light-curve. In total we obtained 234 new magnitudes for the 56 objects, 6 of them with no reported previous measurements. Including the data from the literature we report a total of 109 absolute magnitudes.

  2. A New Gimmick for Assigning Absolute Configuration.

    ERIC Educational Resources Information Center

    Ayorinde, F. O.

    1983-01-01

    A five-step procedure is provided to help students in making the assignment absolute configuration less bothersome. Examples for both single (2-butanol) and multi-chiral carbon (3-chloro-2-butanol) molecules are included. (JN)

  3. The effect of environmental humidity and temperature on skin barrier function and dermatitis.

    PubMed

    Engebretsen, K A; Johansen, J D; Kezic, S; Linneberg, A; Thyssen, J P

    2016-02-01

    Physicians are aware that climatic conditions negatively affect the skin. In particular, people living in equator far countries such as the Northern parts of Europe and North America are exposed to harsh weather during the winter and may experience dry and itchy skin, or deterioration of already existing dermatoses. We searched the literature for studies that evaluated the mechanisms behind this phenomenon. Commonly used meteorological terms such as absolute humidity, relative humidity and dew point are explained. Furthermore, we review the negative effect of low humidity, low temperatures and different seasons on the skin barrier and on the risk of dermatitis. We conclude that low humidity and low temperatures lead to a general decrease in skin barrier function and increased susceptible towards mechanical stress. Since pro-inflammatory cytokines and cortisol are released by keratinocytes, and the number of dermal mast cells increases, the skin also becomes more reactive towards skin irritants and allergens. Collectively, published data show that cold and dry weather increase the prevalence and risk of flares in patients with atopic dermatitis. PMID:26449379

  4. Silver Doped Titanium Dioxide Humidity Sensor

    NASA Astrophysics Data System (ADS)

    Hooshiar Zare, Ali; Mohammadi, Somayye

    2011-02-01

    The effect of silver doping on the sensitivity, dynamic range and the response time of a titanium dioxide-based resistive humidity sensor is studied. Sample pallets were prepared by sintering the dry pressed samples at 900°C in air. Silver was added to the ceramic raw material in the form of AgNO3 which was decomposed during the sintering process. Large area silver electrodes were deposited on the sintered disks by paste printing. The resistance and the response time of the various pallets containing different additive levels were measured at relative humidity range of 4-100%. Silver doping, substantially increased the sensitivity to the ambient humidity. Moreover, it resulted in faster responses; the response time of the silver added pallets were about four times shorter than the pure ones.

  5. All-Optical Graphene Oxide Humidity Sensors

    PubMed Central

    Lim, Weng Hong; Yap, Yuen Kiat; Chong, Wu Yi; Ahmad, Harith

    2014-01-01

    The optical characteristics of graphene oxide (GO) were explored to design and fabricate a GO-based optical humidity sensor. GO film was coated onto a SU8 polymer channel waveguide using the drop-casting technique. The proposed sensor shows a high TE-mode absorption at 1550 nm. Due to the dependence of the dielectric properties of the GO film on water content, this high TE-mode absorption decreases when the ambient relative humidity increases. The proposed sensor shows a rapid response (<1 s) to periodically interrupted humid air flow. The transmission of the proposed sensor shows a linear response of 0.553 dB/% RH in the range of 60% to 100% RH. PMID:25526358

  6. Humidity Dependent Extinction of Clay Aerosols

    NASA Astrophysics Data System (ADS)

    Greenslade, M. E.; Attwood, A. R.

    2010-12-01

    Aerosols play an important role in the Earth’s radiative balance by directly scattering and absorbing radiation. The magnitude of aerosol forcing can be altered by changes in relative humidity which cause aerosol size, shape and refractive index to vary. To quantify these effects, a custom cavity ring down instrument operated at 532 nm with two sample channels measures aerosols extinction under dry conditions and at elevated humidity. The optical growth, fRH(ext), is determined as a ratio of the extinction cross section at high relative humidity to that under dry conditions. Three key clay components of mineral dust and mixtures of clay components with ammonium sulfate are investigated using this method. Experimentally obtained optical growth is compared with physical growth factors from the literature and our work determined using several different techniques. Further, Mie theory calculations based on published optical constants are compared with experimental results. Differences between theory and experiment will be discussed.

  7. Lanthanide-halide based humidity indicators

    DOEpatents

    Beitz, James V.; Williams, Clayton W.

    2008-01-01

    The present invention discloses a lanthanide-halide based humidity indicator and method of producing such indicator. The color of the present invention indicates the humidity of an atmosphere to which it is exposed. For example, impregnating an adsorbent support such as silica gel with an aqueous solution of the europium-containing reagent solution described herein, and dehydrating the support to dryness forms a substance with a yellow color. When this substance is exposed to a humid atmosphere the water vapor from the air is adsorbed into the coating on the pore surface of the silica gel. As the water content of the coating increases, the visual color of the coated silica gel changes from yellow to white. The color change is due to the water combining with the lanthanide-halide complex on the pores of the gel.

  8. Nanomechanical humidity detection through porous alumina cantilevers

    PubMed Central

    Klimenko, Alexey; Lebedev, Vasiliy; Lukashin, Alexey; Eliseev, Andrey

    2015-01-01

    Summary We present here the behavior of the resonance frequency of porous anodic alumina cantilever arrays during water vapor adsorption and emphasize their possible use in the micromechanical sensing of humidity levels at least in the range of 10–22%. The sensitivity of porous anodic aluminium oxide cantilevers (Δf/Δm) and the humidity sensitivity equal about 56 Hz/pg and about 100 Hz/%, respectively. The approach presented here for the design of anodic alumina cantilever arrays by the combination of anodic oxidation and photolithography enables easy control over porosity, surface area, geometric and mechanical characteristics of the cantilever arrays for micromechanical sensing. PMID:26199836

  9. Maple (Computer Algebra System) in Teaching Pre-Calculus: Example of Absolute Value Function

    ERIC Educational Resources Information Center

    Tuluk, Güler

    2014-01-01

    Modules in Computer Algebra Systems (CAS) make Mathematics interesting and easy to understand. The present study focused on the implementation of the algebraic, tabular (numerical), and graphical approaches used for the construction of the concept of absolute value function in teaching mathematical content knowledge along with Maple 9. The study…

  10. Grape anthocyanin altered by absolute sunlight exclusion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This research was conducted to clarify anthocyanin accumulation within ‘Merlot’ grapes in response to microclimate, specifically to light incidence, temperature, and humidity. Treatment grape clusters were light-excluded during ripening by opaque white polypropylene enclosures, during which light in...

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

    PubMed

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

    2009-09-01

    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

  12. The Temperature Humidity Infrared Radiometer (THIR) subsystem

    NASA Technical Reports Server (NTRS)

    Cherrix, G. T.

    1978-01-01

    The infrared radiation from the earth in two spectral bands during both day and night portions of the orbit is measured. Pictures of cloud cover, three dimensional mappings of cloud cover, temperature mappings of clouds, land, and ocean surface, cirrus cloud content, atmospheric contamination, and relative humidity are provided.

  13. A low-power integrated humidity CMOS sensor by printing-on-chip technology.

    PubMed

    Lee, Chang-Hung; Chuang, Wen-Yu; Cowan, Melissa A; Wu, Wen-Jung; Lin, Chih-Ting

    2014-01-01

    A low-power, wide-dynamic-range integrated humidity sensing chip is implemented using a printable polymer sensing material with an on-chip pulse-width-modulation interface circuit. By using the inkjet printing technique, poly(3,4-ethylene-dioxythiophene)/polystyrene sulfonate that has humidity sensing features can be printed onto the top metal layer of a 0.35 μm CMOS IC. The developed printing-on-chip humidity sensor achieves a heterogeneous three dimensional sensor system-on-chip architecture. The humidity sensing of the implemented printing-on-chip sensor system is experimentally tested. The sensor shows a sensitivity of 0.98% to humidity in the atmosphere. The maximum dynamic range of the readout circuit is 9.8 MΩ, which can be further tuned by the frequency of input signal to fit the requirement of the resistance of printed sensor. The power consumption keeps only 154 μW. This printing-on-chip sensor provides a practical solution to fulfill an ultra-small integrated sensor for the applications in miniaturized sensing systems. PMID:24859027

  14. A Low-Power Integrated Humidity CMOS Sensor by Printing-on-Chip Technology

    PubMed Central

    Lee, Chang-Hung; Chuang, Wen-Yu; Cowan, Melissa A.; Wu, Wen-Jung; Lin, Chih-Ting

    2014-01-01

    A low-power, wide-dynamic-range integrated humidity sensing chip is implemented using a printable polymer sensing material with an on-chip pulse-width-modulation interface circuit. By using the inkjet printing technique, poly(3,4-ethylene-dioxythiophene)/polystyrene sulfonate that has humidity sensing features can be printed onto the top metal layer of a 0.35 μm CMOS IC. The developed printing-on-chip humidity sensor achieves a heterogeneous three dimensional sensor system-on-chip architecture. The humidity sensing of the implemented printing-on-chip sensor system is experimentally tested. The sensor shows a sensitivity of 0.98% to humidity in the atmosphere. The maximum dynamic range of the readout circuit is 9.8 MΩ, which can be further tuned by the frequency of input signal to fit the requirement of the resistance of printed sensor. The power consumption keeps only 154 μW. This printing-on-chip sensor provides a practical solution to fulfill an ultra-small integrated sensor for the applications in miniaturized sensing systems. PMID:24859027

  15. Ambient humidity and the skin: the impact of air humidity in healthy and diseased states.

    PubMed

    Goad, N; Gawkrodger, D J

    2016-08-01

    Humidity, along with other climatic factors such as temperature and ultraviolet radiation, can have an important impact on the skin. Limited data suggest that external humidity influences the water content of the stratum corneum. An online literature search was conducted through Pub-Med using combinations of the following keywords: skin, skin disease, humidity, dermatoses, dermatitis, eczema, and mist. Publications included in this review were limited to (i) studies in humans or animals, (ii) publications showing relevance to the field of dermatology, (iii) studies published in English and (iv) publications discussing humidity as an independent influence on skin function. Studies examining environmental factors as composite influences on skin health are only included where the impact of humidity on the skin is also explored in isolation of other environmental factors. A formal systematic review was not feasible for this topic due to the heterogeneity of the available research. Epidemiological studies indicated an increase in eczema with low internal (indoors) humidity and an increase in eczema with external high humidity. Other studies suggest that symptoms of dry skin appear with low humidity internal air-conditioned environments. Murine studies determined that low humidity caused a number of changes in the skin, including the impairment of the desquamation process. Studies in humans demonstrated a reduction in transepidermal water loss (TEWL) (a measure of the integrity of the skin's barrier function) with low humidity, alterations in the water content in the stratum corneum, decreased skin elasticity and increased roughness. Intervention with a humidifying mist increased the water content of the stratum corneum. Conversely, there is some evidence that low humidity conditions can actually improve the barrier function of the skin. Ambient relative humidity has an impact on a range of parameters involved in skin health but the literature is inconclusive. Further

  16. Highly sensitive humidity sensing properties of carbon quantum dots films

    SciTech Connect

    Zhang, Xing; Ming, Hai; Liu, Ruihua; Han, Xiao; Kang, Zhenhui; Liu, Yang; Zhang, Yonglai

    2013-02-15

    Graphical abstract: Display Omitted Highlights: ► A humidity sensing device was fabricated based on carbon quantum dots (CQDs) films. ► The conductivity of the CQDs films shows a linear and rapid response to atmosphere humidity. ► The humidity sensing property was due to the hydrogen bonds between the functional groups on CQDs. -- Abstract: We reported the fabrication of a humidity sensing device based on carbon quantum dots (CQDs) film. The conductivity of the CQDs film has a linear and rapid response to relative humidity, providing the opportunity for the fabrication of humidity sensing devices. The mechanism of our humidity sensor was proposed to be the formation of hydrogen bonds between carbon quantum dots and water molecules in the humidity environment, which significantly promote the electrons migration. In a control experiment, this hypothesis was confirmed by comparing the humidity sensitivity of candle soot (i.e. carbon nanoparticles) with and without oxygen containing groups on the surfaces.

  17. Universal Cosmic Absolute and Modern Science

    NASA Astrophysics Data System (ADS)

    Kostro, Ludwik

    The official Sciences, especially all natural sciences, respect in their researches the principle of methodic naturalism i.e. they consider all phenomena as entirely natural and therefore in their scientific explanations they do never adduce or cite supernatural entities and forces. The purpose of this paper is to show that Modern Science has its own self-existent, self-acting, and self-sufficient Natural All-in Being or Omni-Being i.e. the entire Nature as a Whole that justifies the scientific methodic naturalism. Since this Natural All-in Being is one and only It should be considered as the own scientifically justified Natural Absolute of Science and should be called, in my opinion, the Universal Cosmic Absolute of Modern Science. It will be also shown that the Universal Cosmic Absolute is ontologically enormously stratified and is in its ultimate i.e. in its most fundamental stratum trans-reistic and trans-personal. It means that in its basic stratum. It is neither a Thing or a Person although It contains in Itself all things and persons with all other sentient and conscious individuals as well, On the turn of the 20th century the Science has begun to look for a theory of everything, for a final theory, for a master theory. In my opinion the natural Universal Cosmic Absolute will constitute in such a theory the radical all penetrating Ultimate Basic Reality and will substitute step by step the traditional supernatural personal Absolute.

  18. Data Center Economizer Contamination and Humidity Study

    SciTech Connect

    Shehabi, Arman; Tschudi, William; Gadgil, Ashok

    2007-03-06

    Data centers require continuous air conditioning to address high internal heat loads (heat release from equipment) and maintain indoor temperatures within recommended operating levels for computers. Air economizer cycles, which bring in large amounts of outside air to cool internal loads when weather conditions are favorable, could save cooling energy. There is reluctance from many data center owners to use this common cooling technique, however, due to fear of introducing pollutants and potential loss of humidity control. Concerns about equipment failure from airborne pollutants lead to specifying as little outside air as permissible for human occupants. To investigate contamination levels, particle monitoring was conducted at 8 data centers in Northern California. Particle counters were placed at 3 to 4 different locations within and outside of each data center evaluated in this study. Humidity was also monitored at many of the sites to determine how economizers affect humidity control. Results from this study indicate that economizers do increase the outdoor concentration in data centers, but this concentration, when averaged annually, is still below current particle concentration limits. Study results are summarized below: (1) The average particle concentrations measured at each location, both outside and at the servers, are shown in Table 1. Measurements show low particle concentrations at all data centers without economizers, regardless of outdoor particle concentrations. Particle concentrations were typically an order of magnitude below both outside particle concentrations and recently published ASHRAE standards. (2) Economizer use caused sharp increases in particle concentrations when the economizer vents were open. The particle concentration in the data centers, however, quickly dropped back to pre-economizer levels when the vents closed. Since economizers only allow outside air part of the time, the annual average concentrations still met the ASHRAE

  19. Absolute isotopic abundances of TI in meteorites

    NASA Astrophysics Data System (ADS)

    Niederer, F. R.; Papanastassiou, D. A.; Wasserburg, G. J.

    1985-03-01

    The absolute isotope abundance of Ti has been determined in Ca-Al-rich inclusions from the Allende and Leoville meteorites and in samples of whole meteorites. The absolute Ti isotope abundances differ by a significant mass dependent isotope fractionation transformation from the previously reported abundances, which were normalized for fractionation using 46Ti/48Ti. Therefore, the absolute compositions define distinct nucleosynthetic components from those previously identified or reflect the existence of significant mass dependent isotope fractionation in nature. The authors provide a general formalism for determining the possible isotope compositions of the exotic Ti from the measured composition, for different values of isotope fractionation in nature and for different mixing ratios of the exotic and normal components.

  20. Absolute calibration in vivo measurement systems

    SciTech Connect

    Kruchten, D.A.; Hickman, D.P.

    1991-02-01

    Lawrence Livermore National Laboratory (LLNL) is currently investigating a new method for obtaining absolute calibration factors for radiation measurement systems used to measure internally deposited radionuclides in vivo. Absolute calibration of in vivo measurement systems will eliminate the need to generate a series of human surrogate structures (i.e., phantoms) for calibrating in vivo measurement systems. The absolute calibration of in vivo measurement systems utilizes magnetic resonance imaging (MRI) to define physiological structure, size, and composition. The MRI image provides a digitized representation of the physiological structure, which allows for any mathematical distribution of radionuclides within the body. Using Monte Carlo transport codes, the emission spectrum from the body is predicted. The in vivo measurement equipment is calibrated using the Monte Carlo code and adjusting for the intrinsic properties of the detection system. The calibration factors are verified using measurements of existing phantoms and previously obtained measurements of human volunteers. 8 refs.

  1. Stimulus probability effects in absolute identification.

    PubMed

    Kent, Christopher; Lamberts, Koen

    2016-05-01

    This study investigated the effect of stimulus presentation probability on accuracy and response times in an absolute identification task. Three schedules of presentation were used to investigate the interaction between presentation probability and stimulus position within the set. Data from individual participants indicated strong effects of presentation probability on both proportion correct and response times. The effects were moderated by the ubiquitous stimulus position effect. The accuracy and response time data were predicted by an exemplar-based model of perceptual cognition (Kent & Lamberts, 2005). The bow in discriminability was also attenuated when presentation probability for middle items was relatively high, an effect that will constrain future model development. The study provides evidence for item-specific learning in absolute identification. Implications for other theories of absolute identification are discussed. (PsycINFO Database Record PMID:26478959

  2. Evaluation of Humidity Control Options in Hot-Humid Climate Homes (Fact Sheet)

    SciTech Connect

    Not Available

    2011-12-01

    This technical highlight describes NREL research to analyze the indoor relative humidity in three home types in the hot-humid climate zone, and examine the impacts of various dehumidification equipment and controls. As the Building America program researches construction of homes that achieve greater source energy savings over typical mid-1990s construction, proper modeling of whole-house latent loads and operation of humidity control equipment has become a high priority. Long-term high relative humidity can cause health and durability problems in homes, particularly in a hot-humid climate. In this study, researchers at the National Renewable Energy Laboratory (NREL) used the latest EnergyPlus tool equipped with the moisture capacitance model to analyze the indoor relative humidity in three home types: a Building America high-performance home; a mid-1990s reference home; and a 2006 International Energy Conservation Code (IECC)-compliant home in hot-humid climate zones. They examined the impacts of various dehumidification equipment and controls on the high-performance home where the dehumidification equipment energy use can become a much larger portion of whole-house energy consumption. The research included a number of simulated cases: thermostat reset, A/C with energy recovery ventilator, heat exchanger assisted A/C, A/C with condenser reheat, A/C with desiccant wheel dehumidifier, A/C with DX dehumidifier, A/C with energy recovery ventilator, and DX dehumidifier. Space relative humidity, thermal comfort, and whole-house source energy consumption were compared for indoor relative humidity set points of 50%, 55%, and 60%. The study revealed why similar trends of high humidity were observed in all three homes regardless of energy efficiency, and why humidity problems are not necessarily unique in the high-performance home. Thermal comfort analysis indicated that occupants are unlikely to notice indoor humidity problems. The study confirmed that supplemental

  3. Precise Measurement of the Absolute Fluorescence Yield

    NASA Astrophysics Data System (ADS)

    Ave, M.; Bohacova, M.; Daumiller, K.; Di Carlo, P.; di Giulio, C.; San Luis, P. Facal; Gonzales, D.; Hojvat, C.; Hörandel, J. R.; Hrabovsky, M.; Iarlori, M.; Keilhauer, B.; Klages, H.; Kleifges, M.; Kuehn, F.; Monasor, M.; Nozka, L.; Palatka, M.; Petrera, S.; Privitera, P.; Ridky, J.; Rizi, V.; D'Orfeuil, B. Rouille; Salamida, F.; Schovanek, P.; Smida, R.; Spinka, H.; Ulrich, A.; Verzi, V.; Williams, C.

    2011-09-01

    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.

  4. Absolutely relative or relatively absolute: violations of value invariance in human decision making.

    PubMed

    Teodorescu, Andrei R; Moran, Rani; Usher, Marius

    2016-02-01

    Making decisions based on relative rather than absolute information processing is tied to choice optimality via the accumulation of evidence differences and to canonical neural processing via accumulation of evidence ratios. These theoretical frameworks predict invariance of decision latencies to absolute intensities that maintain differences and ratios, respectively. While information about the absolute values of the choice alternatives is not necessary for choosing the best alternative, it may nevertheless hold valuable information about the context of the decision. To test the sensitivity of human decision making to absolute values, we manipulated the intensities of brightness stimuli pairs while preserving either their differences or their ratios. Although asked to choose the brighter alternative relative to the other, participants responded faster to higher absolute values. Thus, our results provide empirical evidence for human sensitivity to task irrelevant absolute values indicating a hard-wired mechanism that precedes executive control. Computational investigations of several modelling architectures reveal two alternative accounts for this phenomenon, which combine absolute and relative processing. One account involves accumulation of differences with activation dependent processing noise and the other emerges from accumulation of absolute values subject to the temporal dynamics of lateral inhibition. The potential adaptive role of such choice mechanisms is discussed. PMID:26022836

  5. Environmental testing of CIS based modules

    SciTech Connect

    Willett, D.

    1995-11-01

    This report describes environmental testing of Siemen`s CIS modules. Charts and diagrams are presented on data concerning: temporary power loss of laminated mini-modules; the 50 thermal cycle test; the 10 humidity freeze cycle test; results after 1000 hours of exposure to damp heat; and interconnect test structures in damp heat testing. It is concluded that moisture ingress causes permanent increases in the series resistance of modules, and that improved packaging is needed for better high humidity reliability. Also, dry dark heat caused temporary power losses which were recovered in sunlight.

  6. Absolute analytical prediction of photonic crystal guided mode resonance wavelengths

    SciTech Connect

    Hermannsson, Pétur Gordon; Vannahme, Christoph; Smith, Cameron L. C.; Kristensen, Anders

    2014-08-18

    A class of photonic crystal resonant reflectors known as guided mode resonant filters are optical structures that are widely used in the field of refractive index sensing, particularly in biosensing. For the purposes of understanding and design, their behavior has traditionally been modeled numerically with methods such as rigorous coupled wave analysis. Here it is demonstrated how the absolute resonance wavelengths of such structures can be predicted by analytically modeling them as slab waveguides in which the propagation constant is determined by a phase matching condition. The model is experimentally verified to be capable of predicting the absolute resonance wavelengths to an accuracy of within 0.75 nm, as well as resonance wavelength shifts due to changes in cladding index within an accuracy of 0.45 nm across the visible wavelength regime in the case where material dispersion is taken into account. Furthermore, it is demonstrated that the model is valid beyond the limit of low grating modulation, for periodically discontinuous waveguide layers, high refractive index contrasts, and highly dispersive media.

  7. MSTAR: an absolute metrology system with submicrometer accuracy

    NASA Astrophysics Data System (ADS)

    Lay, Oliver P.; Dubovitsky, Serge; Peters, Robert D.; Burger, Johan; Steier, Willian H.; Ahn, Seh-Won; Fetterman, Harrold R.

    2004-10-01

    Laser metrology systems are a key component of stellar interferometers, used to monitor path lengths and dimensions internal to the instrument. Most interferometers use 'relative' metrology, in which the integer number of wavelengths along the path is unknown, and the measurement of length is ambiguous. Changes in the path length can be measured relative to an initial calibration point, but interruption of the metrology beam at any time requires a re-calibration of the system. The MSTAR sensor (Modulation Sideband Technology for Absolute Ranging) is a new system for measuring absolute distance, capable of resolving the integer cycle ambiguity of standard interferometers, and making it possible to measure distance with sub-nanometer accuracy. We describe the design of the system, show results for target distances up to 1 meter, and demonstrate how the system can be scaled to kilometer-scale distances. In recent experiments, we have used white light interferometry to augment the 'truth' measurements and validate the zero-point of the system. MSTAR is a general-purpose tool for conveniently measuring length with much greater accuracy than was previously possible, and has a wide range of possible applications.

  8. Stimulus Probability Effects in Absolute Identification

    ERIC Educational Resources Information Center

    Kent, Christopher; Lamberts, Koen

    2016-01-01

    This study investigated the effect of stimulus presentation probability on accuracy and response times in an absolute identification task. Three schedules of presentation were used to investigate the interaction between presentation probability and stimulus position within the set. Data from individual participants indicated strong effects of…

  9. Increasing Capacity: Practice Effects in Absolute Identification

    ERIC Educational Resources Information Center

    Dodds, Pennie; Donkin, Christopher; Brown, Scott D.; Heathcote, Andrew

    2011-01-01

    In most of the long history of the study of absolute identification--since Miller's (1956) seminal article--a severe limit on performance has been observed, and this limit has resisted improvement even by extensive practice. In a startling result, Rouder, Morey, Cowan, and Pfaltz (2004) found substantially improved performance with practice in the…

  10. Absolute partial photoionization cross sections of ozone.

    SciTech Connect

    Berkowitz, J.; Chemistry

    2008-04-01

    Despite the current concerns about ozone, absolute partial photoionization cross sections for this molecule in the vacuum ultraviolet (valence) region have been unavailable. By eclectic re-evaluation of old/new data and plausible assumptions, such cross sections have been assembled to fill this void.

  11. Solving Absolute Value Equations Algebraically and Geometrically

    ERIC Educational Resources Information Center

    Shiyuan, Wei

    2005-01-01

    The way in which students can improve their comprehension by understanding the geometrical meaning of algebraic equations or solving algebraic equation geometrically is described. Students can experiment with the conditions of the absolute value equation presented, for an interesting way to form an overall understanding of the concept.

  12. Teaching Absolute Value Inequalities to Mature Students

    ERIC Educational Resources Information Center

    Sierpinska, Anna; Bobos, Georgeana; Pruncut, Andreea

    2011-01-01

    This paper gives an account of a teaching experiment on absolute value inequalities, whose aim was to identify characteristics of an approach that would realize the potential of the topic to develop theoretical thinking in students enrolled in prerequisite mathematics courses at a large, urban North American university. The potential is…

  13. Precision absolute positional measurement of laser beams.

    PubMed

    Fitzsimons, Ewan D; Bogenstahl, Johanna; Hough, James; Killow, Christian J; Perreur-Lloyd, Michael; Robertson, David I; Ward, Henry

    2013-04-20

    We describe an instrument which, coupled with a suitable coordinate measuring machine, facilitates the absolute measurement within the machine frame of the propagation direction of a millimeter-scale laser beam to an accuracy of around ±4 μm in position and ±20 μrad in angle. PMID:23669658

  14. On Relative and Absolute Conviction in Mathematics

    ERIC Educational Resources Information Center

    Weber, Keith; Mejia-Ramos, Juan Pablo

    2015-01-01

    Conviction is a central construct in mathematics education research on justification and proof. In this paper, we claim that it is important to distinguish between absolute conviction and relative conviction. We argue that researchers in mathematics education frequently have not done so and this has lead to researchers making unwarranted claims…

  15. Nonequilibrium equalities in absolutely irreversible processes

    NASA Astrophysics Data System (ADS)

    Murashita, Yuto; Funo, Ken; Ueda, Masahito

    2015-03-01

    Nonequilibrium equalities have attracted considerable attention in the context of statistical mechanics and information thermodynamics. Integral nonequilibrium equalities reveal an ensemble property of the entropy production σ as = 1 . Although nonequilibrium equalities apply to rather general nonequilibrium situations, they break down in absolutely irreversible processes, where the forward-path probability vanishes and the entropy production diverges. We identify the mathematical origins of this inapplicability as the singularity of probability measure. As a result, we generalize conventional integral nonequilibrium equalities to absolutely irreversible processes as = 1 -λS , where λS is the probability of the singular part defined based on Lebesgue's decomposition theorem. The acquired equality contains two physical quantities related to irreversibility: σ characterizing ordinary irreversibility and λS describing absolute irreversibility. An inequality derived from the obtained equality demonstrates the absolute irreversibility leads to the fundamental lower bound on the entropy production. We demonstrate the validity of the obtained equality for a simple model.

  16. Absolute Points for Multiple Assignment Problems

    ERIC Educational Resources Information Center

    Adlakha, V.; Kowalski, K.

    2006-01-01

    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…

  17. Wireless sensor for temperature and humidity measurement

    NASA Astrophysics Data System (ADS)

    Drumea, Andrei; Svasta, Paul

    2010-11-01

    Temperature and humidity sensors have a broad range of applications, from heating and ventilation of houses to controlled drying of fruits, vegetables or meat in food industry. Modern sensors are integrated devices, usually MEMS, factory-calibrated and with digital output of measured parameters. They can have power down modes for reduced energy consumption. Such an integrated device allows the implementation of a battery powered wireless sensor when coupled with a low power microcontroller and a radio subsystem. A radio sensor can work independently or together with others in a radio network. Presented paper focuses mainly on measurement and construction aspects of sensors for temperature and humidity designed and implemented by authors; network aspects (communication between two or more sensors) are not analyzed.

  18. Effect of Relative Humidity on Formaldehyde Decontamination

    PubMed Central

    Spiner, David R.; Hoffman, Robert K.

    1971-01-01

    Death rate studies were conducted to determine the effect of varying the concentration, humidity, and type of surface on the sporicidal activity of formaldehyde gas. Washed and unwashed spores were similarly exposed to detect the influence of residual nutrient growth medium upon the rate of kill. The results indicated that the sporicidal activity of formaldehyde gas varies directly with its concentration. Relative humidities (RH) over 50% proved essential for sterility. Spores on a porous surface (cotton cloth) were more readily killed at lower RH than those on a nonporous surface (glass). The reverse occurred at very high RH. At 75% RH, the unwashed spores on glass were killed faster than the washed spores. Images PMID:5002898

  19. Residential Dehumidification Systems Research for Hot-Humid Climates

    SciTech Connect

    2005-02-01

    Twenty homes were tested and monitored in the hot-humid climate of Houston, Texas, to evaluate the humidity control performance and operating cost of six integrated dehumidification and ventilation systems.

  20. Potato growth in response to relative humidity

    NASA Technical Reports Server (NTRS)

    Wheeler, R. M.; Tibbitts, T. W.; Fitzpatrick, A. H.

    1989-01-01

    Potato plants (Solanum tuberosum L. cvs. Russet Burbank, Norland, and Denali) were grown for 56 days in controlled-environment rooms under continuous light at 20C and 50% or 85% RH. No significant differences in total plant dry weight were measured between the humidity treatments, but plants grown under 85% RH produced higher tuber yields. Leaf areas were greater under 50% RH and leaves tended to be larger and darker green than at 85% RH.

  1. Color control in reflection holograms by humidity.

    PubMed

    Wuest, D R; Lakes, R S

    1991-06-10

    A method is presented which permits control of the reconstruction wavelength of reflection holograms and holographic optical elements. This approach makes use of developer and bleach which minimize emulsion shrinkage combined with control of ambient humidity to control the emulsion shrinkage during formation and reconstruction. A simple index matching approach to the elimination of the wood grain effect in reflection holograms is also presented. PMID:20700214

  2. Humidity local measurements in the middle atmosphere

    NASA Astrophysics Data System (ADS)

    Ovarlez, J.; Capus, J.; Forichon, M.; Ovarlez, H.

    1989-06-01

    The development of a hydrometer, to be applied in stratospheric balloons for humidity measurements, is described. The device is also designed for satellite data validation. Data from the experiment carried out in the Southern Hemisphere, in November and December 1988, is discussed. The measurements between 20 and 70 hPa showed a volume mixture ratio from 3 to 6. The mechanism of the equatorial stratosphere drying is considered.

  3. Fiberboard Humidity Data for 9975 Shipping Packages

    SciTech Connect

    Daugherty, W.

    2015-07-31

    The 9975 surveillance program is identifying a technical basis to support extending the storage period of 9975 packages in KAC beyond the currently approved 15 years. A key element of this effort is developing a better understanding of degradation of the fiberboard assembly under storage conditions. This degradation is influenced greatly by the moisture content of the fiberboard, which is not well characterized on an individual package basis. Two efforts have been undertaken to better understand the levels and behavior of moisture within the fiberboard assemblies of the 9975 shipping package. In the first effort, an initial survey of humidity and temperature in the upper air space of 26 packages stored in KAC was made. The data collected within this first effort help to illustrate how the upper air space humidity varies with the local ambient temperature and package heat load. In the second effort, direct measurements of two test packages are providing a correlation between humidity and fiberboard moisture levels within the package, and variations in moisture throughout the fiberboard assembly. This effort has examined packages with cane fiberboard and internal heat levels of 5 and 10W to date. Additional testing is expected to include 15 and 19W heat levels, and then repeat the same four heat levels with softwood fiberboard assemblies. This report documents the data collected to date within these two efforts

  4. Fiberboard humidity data for 9975 shipping packages

    SciTech Connect

    Daugherty, W. L.

    2015-07-31

    The 9975 surveillance program is identifying a technical basis to support extending the storage period of 9975 packages in KAC beyond the currently approved 15 years. A key element of this effort is developing a better understanding of degradation of the fiberboard assembly under storage conditions. This degradation is influenced greatly by the moisture content of the fiberboard, which is not well characterized on an individual package basis.Two efforts have been undertaken to better understand the levels and behavior of moisture within the fiberboard assemblies of the 9975 shipping package. In the first effort, an initial survey of humidity and temperature in the upper air space of 26 packages stored in KAC was made. The data collected within this first effort help to illustrate how the upper air space humidity varies with the local ambient temperature and package heat load. In the second effort, direct measurements of two test packages are providing a correlation between humidity and fiberboard moisture levels within the package, and variations in moisture throughout the fiberboard assembly. This effort has examined packages with cane fiberboard and internal heat levels of 5 and 10W to date. Additional testing is expected to include 15 and 19W heat levels, and then repeat the same four heat levels with softwood fiberboard assemblies. This report documents the data collected to date within these two efforts.

  5. Hydrophilic membrane-based humidity control.

    PubMed

    Scovazzo, P; Burgos, J; Hoehn, A; Todd, P

    1998-10-14

    A dehumidification system for low gravity plant growth experiments requires the generation of no free-liquid condensate and the recovery of water for reuse. In the systems discussed in this paper, the membrane is a barrier between the humid air phase and a liquid-coolant water phase. The coolant water temperature combined with a transmembrane pressure differential establishes a water flux from the humid air into the coolant water. Building on the work of others, we directly compared different hydrophilic membranes for humidity control. In a direct comparison of the hydrophilic membranes, hollow fiber cellulose ester membranes were superior to metal and ceramic membranes in the categories of condensation flux per surface area, ease of start-up, and stability. However, cellulose ester membranes were inferior to metal membranes in one significant category, durability. Dehumidification systems using mixed cellulose ester membranes failed after operational times of only hours to days. We propose that the ratio of fluid surface area to membrane material area (approximately = membrane porosity) controls the relative performances among membranes. In addition, we clarified design equations for operational parameters such as the transmembrane pressure differential. This technology has several potential benefits related to earth environmental issues including the minimization of airborne pathogen release and higher energy efficiency in air conditioning equipment. Utilizing these study results, we designed, constructed, and flew on the space shuttle missions a membrane-based dehumidification system for a plant growth chamber. PMID:11543067

  6. Tropical atmospheric circulations with humidity effects

    PubMed Central

    Hsia, Chun-Hsiung; Lin, Chang-Shou; Ma, Tian; Wang, Shouhong

    2015-01-01

    The main objective of this article is to study the effect of the moisture on the planetary scale atmospheric circulation over the tropics. The modelling we adopt is the Boussinesq equations coupled with a diffusive equation of humidity, and the humidity-dependent heat source is modelled by a linear approximation of the humidity. The rigorous mathematical analysis is carried out using the dynamic transition theory. In particular, we obtain mixed transitions, also known as random transitions, as described in Ma & Wang (2010 Discrete Contin. Dyn. Syst. 26, 1399–1417. (doi:10.3934/dcds.2010.26.1399); 2011 Adv. Atmos. Sci. 28, 612–622. (doi:10.1007/s00376-010-9089-0)). The analysis also indicates the need to include turbulent friction terms in the model to obtain correct convection scales for the large-scale tropical atmospheric circulations, leading in particular to the right critical temperature gradient and the length scale for the Walker circulation. In short, the analysis shows that the effect of moisture lowers the magnitude of the critical thermal Rayleigh number and does not change the essential characteristics of dynamical behaviour of the system. PMID:25568615

  7. 40 CFR 90.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 21 2012-07-01 2012-07-01 false Engine intake air humidity measurement... Emission Test Equipment Provisions § 90.310 Engine intake air humidity measurement. This section refers to... for the engine intake air, the ambient test cell humidity measurement may be used. (a)...

  8. 40 CFR 90.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air humidity measurement... Emission Test Equipment Provisions § 90.310 Engine intake air humidity measurement. This section refers to... for the engine intake air, the ambient test cell humidity measurement may be used. (a)...

  9. 40 CFR 90.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 20 2014-07-01 2013-07-01 true Engine intake air humidity measurement... Emission Test Equipment Provisions § 90.310 Engine intake air humidity measurement. This section refers to... for the engine intake air, the ambient test cell humidity measurement may be used. (a)...

  10. 40 CFR 90.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 21 2013-07-01 2013-07-01 false Engine intake air humidity measurement... Emission Test Equipment Provisions § 90.310 Engine intake air humidity measurement. This section refers to... for the engine intake air, the ambient test cell humidity measurement may be used. (a)...

  11. 40 CFR 90.310 - Engine intake air humidity measurement.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Engine intake air humidity measurement... Emission Test Equipment Provisions § 90.310 Engine intake air humidity measurement. This section refers to... for the engine intake air, the ambient test cell humidity measurement may be used. (a)...

  12. 7 CFR 28.301 - Measurement: humidity; temperature.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 2 2014-01-01 2014-01-01 false Measurement: humidity; temperature. 28.301 Section 28... for Length of Staple § 28.301 Measurement: humidity; temperature. The length of staple of any cotton... its fibers under a relative humidity of the atmosphere of 65 percent and a temperature of 70 °F....

  13. 7 CFR 28.301 - Measurement: humidity; temperature.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 2 2011-01-01 2011-01-01 false Measurement: humidity; temperature. 28.301 Section 28... for Length of Staple § 28.301 Measurement: humidity; temperature. The length of staple of any cotton... its fibers under a relative humidity of the atmosphere of 65 percent and a temperature of 70 °F....

  14. 7 CFR 28.301 - Measurement: humidity; temperature.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 2 2013-01-01 2013-01-01 false Measurement: humidity; temperature. 28.301 Section 28... for Length of Staple § 28.301 Measurement: humidity; temperature. The length of staple of any cotton... its fibers under a relative humidity of the atmosphere of 65 percent and a temperature of 70 °F....

  15. 7 CFR 28.301 - Measurement: humidity; temperature.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 2 2012-01-01 2012-01-01 false Measurement: humidity; temperature. 28.301 Section 28... for Length of Staple § 28.301 Measurement: humidity; temperature. The length of staple of any cotton... its fibers under a relative humidity of the atmosphere of 65 percent and a temperature of 70 °F....

  16. 7 CFR 28.301 - Measurement: humidity; temperature.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Measurement: humidity; temperature. 28.301 Section 28... for Length of Staple § 28.301 Measurement: humidity; temperature. The length of staple of any cotton... its fibers under a relative humidity of the atmosphere of 65 percent and a temperature of 70° F....

  17. Combined Use of Absolute and Differential Seismic Arrival Time Data to Improve Absolute Event Location

    NASA Astrophysics Data System (ADS)

    Myers, S.; Johannesson, G.

    2012-12-01

    Arrival time measurements based on waveform cross correlation are becoming more common as advanced signal processing methods are applied to seismic data archives and real-time data streams. Waveform correlation can precisely measure the time difference between the arrival of two phases, and differential time data can be used to constrain relative location of events. Absolute locations are needed for many applications, which generally requires the use of absolute time data. Current methods for measuring absolute time data are approximately two orders of magnitude less precise than differential time measurements. To exploit the strengths of both absolute and differential time data, we extend our multiple-event location method Bayesloc, which previously used absolute time data only, to include the use of differential time measurements that are based on waveform cross correlation. Fundamentally, Bayesloc is a formulation of the joint probability over all parameters comprising the multiple event location system. The Markov-Chain Monte Carlo method is used to sample from the joint probability distribution given arrival data sets. The differential time component of Bayesloc includes scaling a stochastic estimate of differential time measurement precision based the waveform correlation coefficient for each datum. For a regional-distance synthetic data set with absolute and differential time measurement error of 0.25 seconds and 0.01 second, respectively, epicenter location accuracy is improved from and average of 1.05 km when solely absolute time data are used to 0.28 km when absolute and differential time data are used jointly (73% improvement). The improvement in absolute location accuracy is the result of conditionally limiting absolute location probability regions based on the precise relative position with respect to neighboring events. Bayesloc estimates of data precision are found to be accurate for the synthetic test, with absolute and differential time measurement

  18. Desiccant Humidity Control System Using Waste Heat of Water Source Heat Pump

    NASA Astrophysics Data System (ADS)

    Wada, Kazuki; Mashimo, Kouichi; Takahashi, Mikio; Tanaka, Kitoshi; Toya, Saburo; Tateyama, Ryotaro; Miyamoto, Kazuhiro; Yamaguchi, Masahiro

    The authors hope to develop an air-conditioning system that processes the latent heat load and the sensible heat load separately. This would enable the efficiency of the chilling unit to be improved because the temperature of the chilled water used for cooling would be higher than normal. However, if lukewarm water is used, there is insufficient cooling and dehumidification. Therefore, a dehumidifier such as a desiccant air-conditioning system is needed. Using the waste heat generated when the desiccant air-conditioning system is in operation increases efficiency. The authors are developing a prototype desiccant humidity control system that makes use of the waste heat generated by a water source heat pump. This paper describes the results of an experiment that was conducted for this prototype based on the assumption that it would be installed in an office building. The dehumidification performance achieved was sufficient to process the indoor latent heat load. The prototype was able to adjust the indoor relative humidity from 40% to 60% under conditions in which the indoor latent heat load varied. Humidification without the use of water was possible even in the absence of an indoor latent heat load when the outdoor absolute humidity was 3.5 g/kg' or more.

  19. Adaptive neuro-fuzzy inference system for temperature and humidity profile retrieval from microwave radiometer observations

    NASA Astrophysics Data System (ADS)

    Ramesh, K.; Kesarkar, A. P.; Bhate, J.; Venkat Ratnam, M.; Jayaraman, A.

    2015-01-01

    The retrieval of accurate profiles of temperature and water vapour is important for the study of atmospheric convection. Recent development in computational techniques motivated us to use adaptive techniques in the retrieval algorithms. In this work, we have used an adaptive neuro-fuzzy inference system (ANFIS) to retrieve profiles of temperature and humidity up to 10 km over the tropical station Gadanki (13.5° N, 79.2° E), India. ANFIS is trained by using observations of temperature and humidity measurements by co-located Meisei GPS radiosonde (henceforth referred to as radiosonde) and microwave brightness temperatures observed by radiometrics multichannel microwave radiometer MP3000 (MWR). ANFIS is trained by considering these observations during rainy and non-rainy days (ANFIS(RD + NRD)) and during non-rainy days only (ANFIS(NRD)). The comparison of ANFIS(RD + NRD) and ANFIS(NRD) profiles with independent radiosonde observations and profiles retrieved using multivariate linear regression (MVLR: RD + NRD and NRD) and artificial neural network (ANN) indicated that the errors in the ANFIS(RD + NRD) are less compared to other retrieval methods. The Pearson product movement correlation coefficient (r) between retrieved and observed profiles is more than 92% for temperature profiles for all techniques and more than 99% for the ANFIS(RD + NRD) technique Therefore this new techniques is relatively better for the retrieval of temperature profiles. The comparison of bias, mean absolute error (MAE), RMSE and symmetric mean absolute percentage error (SMAPE) of retrieved temperature and relative humidity (RH) profiles using ANN and ANFIS also indicated that profiles retrieved using ANFIS(RD + NRD) are significantly better compared to the ANN technique. The analysis of profiles concludes that retrieved profiles using ANFIS techniques have improved the temperature retrievals substantially; however, the retrieval of RH by all techniques considered in this paper (ANN, MVLR and

  20. Terrestrial Photovoltaic Module Accelerated Test-To-Failure Protocol

    SciTech Connect

    Osterwald, C. R.

    2008-03-01

    This technical report documents a test-to-failure protocol that may be used to obtain quantitative information about the reliability of photovoltaic modules using accelerated testing in environmental temperature-humidity chambers.

  1. Long-distance recording of the humidity over the sea

    NASA Technical Reports Server (NTRS)

    Buklanov, V. V.; Klaptsov, V. M.

    1975-01-01

    A procedure is developed for long distance recording of humidity over the sea that uses humidity detectors of the sorption type, whose electrical properties depend on the relative humidity of the air. The moisture sensitive material of the hygristor is the organic polymer polyacrylonitryl, deposited on silver electrodes and thermally treated. In the measurements of the relative humidity from 60% to 95%, the resistance of the hygristor varies from several hundred kiloohms to a few kiloohms, and is an essentially nonlinear function of the humidity.

  2. Effect of humidity on infection of turkeys with Alcaligenes faecalis.

    PubMed

    Slavik, M F; Skeeles, J K; Beasley, J N; Harris, G C; Roblee, P; Hellwig, D

    1981-01-01

    Turkeys maintained at 75% to 80% relative humidity were more adversely affected by Alcaligenes faecalis infection than turkeys maintained at 20 to 35% relative humidity. Alcaligenes faecalis was reisolated earlier and more often from turkeys maintained at the higher humidity. Clinically, the turkeys maintained at high humidity exhibited both sinusitis and conjunctivitis earlier than the turkeys at low humidity. In both groups, antibody titers as determined by a microagglutination test developed by 2 weeks postinoculation and started to decline after the third week, lymphocytosis was demonstrated at 1 week postinoculation, and a lymphopenia developed at 5 weeks postinoculation. PMID:7337613

  3. Absolute calibration of TFTR helium proportional counters

    SciTech Connect

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

    1995-06-01

    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 msec and 50 msec 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.

  4. Absolute enantioselective separation: optical activity ex machina.

    PubMed

    Bielski, Roman; Tencer, Michal

    2005-11-01

    The paper describes methodology of using three independent macroscopic factors affecting molecular orientation to accomplish separation of a racemic mixture without the presence of any other chiral compounds, i. e., absolute enantioselective separation (AES) which is an extension of a concept of applying these factors to absolute asymmetric synthesis. The three factors may be applied simultaneously or, if their effects can be retained, consecutively. The resulting three mutually orthogonal or near orthogonal directors constitute a true chiral influence and their scalar triple product is the measure of the chirality of the system. AES can be executed in a chromatography-like microfluidic process in the presence of an electric field. It may be carried out on a chemically modified flat surface, a monolithic polymer column made of a mesoporous material, each having imparted directional properties. Separation parameters were estimated for these media and possible implications for the natural homochirality are discussed. PMID:16342798

  5. Absolute and relative dosimetry for ELIMED

    SciTech Connect

    Cirrone, G. A. P.; Schillaci, F.; Scuderi, V.; Cuttone, G.; Candiano, G.; Musumarra, A.; Pisciotta, P.; Romano, F.; Carpinelli, M.; Presti, D. Lo; Raffaele, L.; Tramontana, A.; Cirio, R.; Sacchi, R.; Monaco, V.; Marchetto, F.; Giordanengo, S.

    2013-07-26

    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.

  6. Probing absolute spin polarization at the nanoscale.

    PubMed

    Eltschka, Matthias; Jäck, Berthold; Assig, Maximilian; Kondrashov, Oleg V; Skvortsov, Mikhail A; Etzkorn, Markus; Ast, Christian R; Kern, Klaus

    2014-12-10

    Probing absolute values of spin polarization at the nanoscale offers insight into the fundamental mechanisms of spin-dependent transport. Employing the Zeeman splitting in superconducting tips (Meservey-Tedrow-Fulde effect), we introduce a novel spin-polarized scanning tunneling microscopy that combines the probing capability of the absolute values of spin polarization with precise control at the atomic scale. We utilize our novel approach to measure the locally resolved spin polarization of magnetic Co nanoislands on Cu(111). We find that the spin polarization is enhanced by 65% when increasing the width of the tunnel barrier by only 2.3 Å due to the different decay of the electron orbitals into vacuum. PMID:25423049

  7. Absolute-magnitude distributions of supernovae

    SciTech Connect

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

    2014-05-01

    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 (M{sub B} < –21) make up only about 0.1% of all SNe in the bias-corrected sample. The subluminous events (M{sub B} > –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.

  8. Absolute radiometry and the solar constant

    NASA Technical Reports Server (NTRS)

    Willson, R. C.

    1974-01-01

    A series of active cavity radiometers (ACRs) are described which have been developed as standard detectors for the accurate measurement of irradiance in absolute units. It is noted that the ACR is an electrical substitution calorimeter, is designed for automatic remote operation in any environment, and can make irradiance measurements in the range from low-level IR fluxes up to 30 solar constants with small absolute uncertainty. The instrument operates in a differential mode by chopping the radiant flux to be measured at a slow rate, and irradiance is determined from two electrical power measurements together with the instrumental constant. Results are reported for measurements of the solar constant with two types of ACRs. The more accurate measurement yielded a value of 136.6 plus or minus 0.7 mW/sq cm (1.958 plus or minus 0.010 cal/sq cm per min).

  9. Asteroid absolute magnitudes and slope parameters

    NASA Technical Reports Server (NTRS)

    Tedesco, Edward F.

    1991-01-01

    A new listing of absolute magnitudes (H) and slope parameters (G) has been created and published in the Minor Planet Circulars; this same listing will appear in the 1992 Ephemerides of Minor Planets. Unlike previous listings, the values of the current list were derived from fits of data at the V band. All observations were reduced in the same fashion using, where appropriate, a single basis default value of 0.15 for the slope parameter. Distances and phase angles were computed for each observation. The data for 113 asteroids was of sufficiently high quality to permit derivation of their H and G. These improved absolute magnitudes and slope parameters will be used to deduce the most reliable bias-corrected asteroid size-frequency distribution yet made.

  10. From Hubble's NGSL to Absolute Fluxes

    NASA Technical Reports Server (NTRS)

    Heap, Sara R.; Lindler, Don

    2012-01-01

    Hubble's Next Generation Spectral Library (NGSL) consists of R-l000 spectra of 374 stars of assorted temperature, gravity, and metallicity. Each spectrum covers the wavelength range, 0.18-1.00 microns. The library can be viewed and/or downloaded from the website, http://archive.stsci.edu/prepds/stisngsll. Stars in the NGSL are now being used as absolute flux standards at ground-based observatories. However, the uncertainty in the absolute flux is about 2%, which does not meet the requirements of dark-energy surveys. We are therefore developing an observing procedure that should yield fluxes with uncertainties less than 1 % and will take part in an HST proposal to observe up to 15 stars using this new procedure.