WorldWideScience

Sample records for measured air distribution

  1. Measurements and predictions of the air distribution systems in high compute density (Internet) data centers

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Jinkyun [HIMEC (Hanil Mechanical Electrical Consultants) Ltd., Seoul 150-103 (Korea); Department of Architectural Engineering, Yonsei University, Seoul 120-749 (Korea); Lim, Taesub; Kim, Byungseon Sean [Department of Architectural Engineering, Yonsei University, Seoul 120-749 (Korea)

    2009-10-15

    When equipment power density increases, a critical goal of a data center cooling system is to separate the equipment exhaust air from the equipment intake air in order to prevent the IT server from overheating. Cooling systems for data centers are primarily differentiated according to the way they distribute air. The six combinations of flooded and locally ducted air distribution make up the vast majority of all installations, except fully ducted air distribution methods. Once the air distribution system (ADS) is selected, there are other elements that must be integrated into the system design. In this research, the design parameters and IT environmental aspects of the cooling system were studied with a high heat density data center. CFD simulation analysis was carried out in order to compare the heat removal efficiencies of various air distribution systems. The IT environment of an actual operating data center is measured to validate a model for predicting the effect of different air distribution systems. A method for planning and design of the appropriate air distribution system is described. IT professionals versed in precision air distribution mechanisms, components, and configurations can work more effectively with mechanical engineers to ensure the specification and design of optimized cooling solutions. (author)

  2. Measurement of concentration and size distribution of radon decay products in homes using air cleaners

    International Nuclear Information System (INIS)

    Montassier, N.; Hopke, P.K.; Shi, Y.; McCallum, B.

    1992-01-01

    By removing particles, air cleaners can also eliminate radon decay products. However, by removing the particles, the open-quotes unattachedclose quotes fraction of the radon progeny is increased leading to a higher dose per unit exposure. Thus, both the concentration and size distributions of the radon decay products are needed to evaluate air cleaners. Three types of room air cleaners, NO-RAD Radon Removal System, Electronic Air Cleaner and PUREFLOW Air Treatment System were tested in a single family home in Arnprior, Ontario (Canada). Semi-continuous measurements of radon gas concentration and radon decay product activity weighted size distribution were performed in the kitchen/dining room under real living conditions. The effects of air cleaners on both the concentration and size distribution of the radon decay products were measured, and their impact on the dose of radiation given to the lung tissue were examined

  3. On the feasibility of measuring urban air pollution by wireless distributed sensor networks.

    Science.gov (United States)

    Moltchanov, Sharon; Levy, Ilan; Etzion, Yael; Lerner, Uri; Broday, David M; Fishbain, Barak

    2015-01-01

    Accurate evaluation of air pollution on human-wellbeing requires high-resolution measurements. Standard air quality monitoring stations provide accurate pollution levels but due to their sparse distribution they cannot capture the highly resolved spatial variations within cities. Similarly, dedicated field campaigns can use tens of measurement devices and obtain highly dense spatial coverage but normally deployment has been limited to short periods of no more than few weeks. Nowadays, advances in communication and sensory technologies enable the deployment of dense grids of wireless distributed air monitoring nodes, yet their sensor ability to capture the spatiotemporal pollutant variability at the sub-neighborhood scale has never been thoroughly tested. This study reports ambient measurements of gaseous air pollutants by a network of six wireless multi-sensor miniature nodes that have been deployed in three urban sites, about 150 m apart. We demonstrate the network's capability to capture spatiotemporal concentration variations at an exceptional fine resolution but highlight the need for a frequent in-situ calibration to maintain the consistency of some sensors. Accordingly, a procedure for a field calibration is proposed and shown to improve the system's performance. Overall, our results support the compatibility of wireless distributed sensor networks for measuring urban air pollution at a sub-neighborhood spatial resolution, which suits the requirement for highly spatiotemporal resolved measurements at the breathing-height when assessing exposure to urban air pollution. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Air method measurements of apple vessel length distributions with improved apparatus and theory

    Science.gov (United States)

    Shabtal Cohen; John Bennink; Mel Tyree

    2003-01-01

    Studies showing that rootstock dwarfing potential is related to plant hydraulic conductance led to the hypothesis that xylem properties are also related. Vessel length distribution and other properties of apple wood from a series of varieties were measured using the 'air method' in order to test this hypothesis. Apparatus was built to measure and monitor...

  5. Wireless Distributed Environmental Sensor Networks for Air Pollution Measurement-The Promise and the Current Reality.

    Science.gov (United States)

    Broday, David M

    2017-10-02

    The evaluation of the effects of air pollution on public health and human-wellbeing requires reliable data. Standard air quality monitoring stations provide accurate measurements of airborne pollutant levels, but, due to their sparse distribution, they cannot capture accurately the spatial variability of air pollutant concentrations within cities. Dedicated in-depth field campaigns have dense spatial coverage of the measurements but are held for relatively short time periods. Hence, their representativeness is limited. Moreover, the oftentimes integrated measurements represent time-averaged records. Recent advances in communication and sensor technologies enable the deployment of dense grids of Wireless Distributed Environmental Sensor Networks for air quality monitoring, yet their capability to capture urban-scale spatiotemporal pollutant patterns has not been thoroughly examined to date. Here, we summarize our studies on the practicalities of using data streams from sensor nodes for air quality measurement and the required methods to tune the results to different stakeholders and applications. We summarize the results from eight cities across Europe, five sensor technologies-three stationary (with one tested also while moving) and two personal sensor platforms, and eight ambient pollutants. Overall, few sensors showed an exceptional and consistent performance, which can shed light on the fine spatiotemporal urban variability of pollutant concentrations. Stationary sensor nodes were more reliable than personal nodes. In general, the sensor measurements tend to suffer from the interference of various environmental factors and require frequent calibrations. This calls for the development of suitable field calibration procedures, and several such in situ field calibrations are presented.

  6. Global distribution of mean age of stratospheric air from MIPAS SF6 measurements

    Directory of Open Access Journals (Sweden)

    H. Fischer

    2008-02-01

    Full Text Available Global distributions of profiles of sulphur hexafluoride (SF6 have been retrieved from limb emission spectra recorded by the Michelson Interferometer for Passive Atmospheric Sounding (MIPAS on Envisat covering the period September 2002 to March 2004. Individual SF6 profiles have a precision of 0.5 pptv below 25 km altitude and a vertical resolution of 4–6 km up to 35 km altitude. These data have been validated versus in situ observations obtained during balloon flights of a cryogenic whole-air sampler. For the tropical troposphere a trend of 0.230±0.008 pptv/yr has been derived from the MIPAS data, which is in excellent agreement with the trend from ground-based flask and in situ measurements from the National Oceanic and Atmospheric Administration Earth System Research Laboratory, Global Monitoring Division. For the data set currently available, based on at least three days of data per month, monthly 5° latitude mean values have a 1σ standard error of 1%. From the global SF6 distributions, global daily and monthly distributions of the apparent mean age of air are inferred by application of the tropical tropospheric trend derived from MIPAS data. The inferred mean ages are provided for the full globe up to 90° N/S, and have a 1σ standard error of 0.25 yr. They range between 0 (near the tropical tropopause and 7 years (except for situations of mesospheric intrusions and agree well with earlier observations. The seasonal variation of the mean age of stratospheric air indicates episodes of severe intrusion of mesospheric air during each Northern and Southern polar winter observed, long-lasting remnants of old, subsided polar winter air over the spring and summer poles, and a rather short period of mixing with midlatitude air and/or upward transport during fall in October/November (NH and April/May (SH, respectively, with small latitudinal gradients, immediately before the new polar vortex starts to form. The mean age distributions further

  7. LASE Measurements of Water Vapor, Aerosol, and Cloud Distributions in Saharan Air Layers and Tropical Disturbances

    Science.gov (United States)

    Ismail, Syed; Ferrare, Richard A.; Browell, Edward V.; Kooi, Susan A.; Dunion, Jason P.; Heymsfield, Gerry; Notari, Anthony; Butler, Carolyn F.; Burton, Sharon; Fenn, Marta; hide

    2010-01-01

    LASE (Lidar Atmospheric Sensing Experiment) on-board the NASA DC-8 measured high resolution profiles of water vapor and aerosols, and cloud distributions in 14 flights over the eastern North Atlantic during the NAMMA (NASA African Monsoon Multidisciplinary Analyses) field experiment. These measurements were used to study African easterly waves (AEWs), tropical cyclones (TCs), and the Saharan Air Layer(s) (SAL). Interactions between the SAL and tropical air were observed during the early stages of the TC development. These LASE measurements represent the first simultaneous water vapor and aerosol lidar measurements to study the SAL and its impact on AEWs and TCs. Examples of profile measurements of aerosol scattering ratios, aerosol extinction coefficients, aerosol optical thickness, water vapor mixing ratios, RH, and temperature are presented to illustrate their characteristics in SAL, convection, and clear air regions. LASE data suggest that the SAL suppresses low-altitude convection at the convection-SAL interface region. Mid-level convection associated with the AEW and transport are likely responsible for high water vapor content observed in the southern regions of the SAL on August 20, 2008. This interaction is responsible for the transfer of about 7 x 10(exp 15) J latent heat energy within a day to the SAL. Measurements of lidar extinction-to-backscatter ratios in the range 36+/-5 to 45+/-5 are within the range of measurements from other lidar measurements of dust. LASE aerosol extinction and water vapor profiles are validated by comparison with onboard in situ aerosol measurements and GPS dropsonde water vapor soundings, respectively.

  8. Computation and measurement of air temperature distribution of an industrial melt blowing die

    Directory of Open Access Journals (Sweden)

    Wu Li-Li

    2014-01-01

    Full Text Available The air flow field of the dual slot die on an HDF-6D melt blowing non-woven equipment is computed numerically. A temperature measurement system is built to measure air temperatures. The computation results tally with the measured results proving the correctness of the computation. The results have great valuable significance in the actual melt blowing production.

  9. Direct measurement of homogeneously distributed radioactive air contamination with germanium detectors

    International Nuclear Information System (INIS)

    Sowa, W.

    1990-01-01

    Air contamination by γ emitting radionuclides was measured with a vertically arranged germanium detector, laterally shielded by a lead ring, and calibration factors and detection limits of a number of fission products determined. The possibility of measuring simultaneously existing air and soil contamination by measurements with and without lead shield is described. The change of detection limit of air contamination is presented for different soil contamination levels by the same radionuclide. Calibration factors are given to determine the dose rate on the ground due to air contamination by different radionuclides. (author)

  10. Evaluation of the probability distribution of intake from a single measurement on a personal air sampler

    International Nuclear Information System (INIS)

    Birchall, A.; Muirhead, C.R.; James, A.C.

    1988-01-01

    An analytical expression has been derived for the k-sum distribution, formed by summing k random variables from a lognormal population. Poisson statistics are used with this distribution to derive distribution of intake when breathing an atmosphere with a constant particle number concentration. Bayesian inference is then used to calculate the posterior probability distribution of concentrations from a given measurement. This is combined with the above intake distribution to give the probability distribution of intake resulting from a single measurement of activity made by an ideal sampler. It is shown that the probability distribution of intake is very dependent on the prior distribution used in Bayes' theorem. The usual prior assumption, that all number concentrations are equally probable, leads to an imbalance in the posterior intake distribution. This can be resolved if a new prior proportional to w -2/3 is used, where w is the expected number of particles collected. (author)

  11. Advanced air distribution

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor

    2011-01-01

    The aim of total volume air distribution (TVAD) involves achieving uniform temperature and velocity in the occupied zone and environment designed for an average occupant. The supply of large amounts of clean and cool air are needed to maintain temperature and pollution concentration at acceptable...... levels in the entire space, leading to increased energy consumption and the use of large and costly HVAC and duct systems. The performance of desk installed PV combined with background TVAD used for room temperature control has been studied in an office building located in a hot and humid climate....... Ventilation in hospitals is essential to decrease the risk of airborne cross-infection. At present, mixing air distribution at a minimum of 12 ach is used in infection wards. Advanced air distribution has the potential to aid in achieving healthy, comfortable and productive indoor environments at levels...

  12. Distribution of IOP measured with an air puff tonometer in a young population.

    Science.gov (United States)

    Hashemi, Hassan; Khabazkhoob, Mehdi; Nabovati, Payam; Yazdani, Negareh; Ostadimoghaddam, Hadi; Shiralivand, Ehsan; Derakhshan, Akbar; Yekta, AbbasAli

    2018-03-01

    To determine the normal range of intraocular pressure (IOP) in the young and its association with certain corneal parameters using a non-contact device. Subjects were selected from students of Mashhad University of Medical Sciences through stratified sampling. All participants had visual acuity testing, corneal imaging, a comprehensive slit-lamp examination by an ophthalmologist, and IOP measurement using a non-contact air-puff tonometer. Of the 1280 invitees, 1073 (83.8%) participated, and 1027 were eligible. Mean IOP was 16.38 mmHg [95% confidence interval (CI): 16.22-16.53] in the total sample, 16.14 mmHg (95% CI: 15.84-16.45) in men, and 16.48 mmHg (95% CI: 16.31-16.66) in women. There was a significant IOP difference between myopes and emmetropes ( P  = 0.031). Based on the multiple linear regression model, IOP associated directly with age and central corneal thickness (CCT), and inversely with corneal diameter, spherical equivalent (SE), and keratoconus. Based on standardized coefficients of the regression model, CCT and SE had the strongest association with IOP. In the present study, we demonstrated the IOP distribution in a young population using a non-contact method. CCT and SE were strongly associated with IOP.

  13. Measurement of the size distributions of radon progeny in indoor air

    International Nuclear Information System (INIS)

    Hopke, P.K.; Ramamurthi, M.; Li, C.S.

    1990-01-01

    A major problem in evaluating the health risk posed by airborne radon progeny in indoor atmospheres is the lack of available information on the activity-weighted size distributions that occur in the domestic environment. With an automated, semicontinuous, graded screen array system, we made a series of measurements of activity-weighted size distributions in several houses in the northeastern United States. Measurements were made in an unoccupied house, in which human aerosol-generating activities were simulated. The time evolution of the aerosol size distribution was measured in each situation. Results of these measurements are presented

  14. Air Distribution in Rooms

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    The research on air distribution in rooms is often done as full-size investigations, scale-model investigations or by Computational Fluid Dynamics (CFD). New activities have taken place within all three areas and this paper draws comparisons between the different methods. The outcome of the l......EA sponsored research "Air Flow Pattern within Buildings" is used for comparisons in some parts of the paper because various types of experiments and many countries are involved....

  15. Moisture Distribution in Broccoli: Measurements by MRI Hot Air Drying Experiments

    NARCIS (Netherlands)

    Jin, X.; Sman, van der R.G.M.; Gerkema, E.; Vergeldt, F.J.; As, van H.; Boxtel, van A.J.B.

    2011-01-01

    ABSTRACT The internal moisture distribution that arise in food products during drying, is a key factor for the retention of quality attributes. To reveal the course of moisture content in a product, internal moisture profiles in broccoli florets are measured by MRI imaging during drying experiments

  16. Moisture distribution in broccoli: measurements by MRI hot air drying experiments

    NARCIS (Netherlands)

    Jin, X.; Sman, van der R.G.M.; Gerkema, E.; Vergeldt, F.J.; As, van H.; Boxtel, van A.J.B.

    2011-01-01

    The internal moisture distribution that arise in food products during drying, is a key factor for the retention of quality attributes. To reveal the course of moisture content in a product, internal moisture profiles in broccoli florets are measured by MRI imaging during drying experiments with

  17. Velocity and phase distribution measurements in vertical air-water annular flows

    International Nuclear Information System (INIS)

    Vassallo, P.

    1997-07-01

    Annular flow topology for three air-water conditions in a vertical duct is investigated through the use of a traversing double-sensor hot-film anemometry probe and differential pressure measurements. Near wall measurements of mean and fluctuating velocities, as well as local void fraction, are taken in the liquid film, with the highest turbulent fluctuations occurring for the flow condition with the largest pressure drop. A modified law-of-the-wall formulation for wall shear is presented which, using near wall values of mean velocity and kinetic energy, agrees reasonably well with the average stress obtained from direct pressure drop measurements. The linear profile using wall coordinates in the logarithmic layer is preserved in annular flow; however, the slope and intercept of the profile differ from the single-phase values for the annular flow condition which has a thicker, more turbulent, liquid film

  18. Measurements of the spatial distribution of tritium in air above a chronically contaminated surface

    International Nuclear Information System (INIS)

    Workman, W.J.G.; Davis, P.A.; Wood, M.J.; Barry, P.J.

    1993-01-01

    Tritium in air (HTO) concentrations were measured over a 13 month period above a surface that is chronically contaminated by tritium-bearing groundwater from a waste management area. The measurements were made using passive diffusion samplers, which were sited at six locations (about 100 m apart) at 0.15, 0.9, and 1.8 m above ground level. The diffusion samplers were compact, sampled at a known rate, and required no external power source. They are ideal for remote locations and require a minimum of effort to collect and analyze the data. HTO-in-air concentration peaked in the summer at 500-1500 Bq.m -3 and decreased in the winter to 1-120 Bq.m -3 . In general, concentration decreased with height above ground level, implying that HTO is being lost from the surface to the atmosphere. The flux of tritium to the atmosphere must, therefore, be taken into account to estimate the tritium mass balance for a contaminated area. (Author) 3 figs., 5 tabs., 10 refs

  19. Wireless distributed environmental sensor networks for air pollution measurement-the promise and the current reality

    Czech Academy of Sciences Publication Activity Database

    Broday, D. M.; Arpaci, A.; Bartoňová, A.; Castell-Balaguer, N.; Cole-Hunter, T.; Dauge, F.R.; Fishbain, B.; Jones, R.L.; Galea, K.; Jovasevic-Stojanovic, M.; Kocman, D.; Martinez-Iniguez, T.; Nieuwenhuijsen, M.; Robinson, J.; Švecová, Vlasta; Thai, P.

    2017-01-01

    Roč. 17, č. 10 (2017), s. 2263 ISSN 1424-8220 Institutional support: RVO:68378041 Keywords : air pollution * in situ field calibration * micro sensing units Subject RIV: EI - Biotechnology ; Bionics OBOR OECD: Biomaterials (as related to medical implants, devices, sensors) Impact factor: 2.677, year: 2016

  20. Measuring centimeter-resolution air temperature profiles above land and water using fiber-optic Distributed Temperature Sensing

    Science.gov (United States)

    Sigmund, Armin; Pfister, Lena; Olesch, Johannes; Thomas, Christoph K.

    2016-04-01

    The precise determination of near-surface air temperature profiles is of special importance for the characterization of airflows (e.g. cold air) and the quantification of sensible heat fluxes according to the flux-gradient similarity approach. In contrast to conventional multi-sensor techniques, measuring temperature profiles using fiber-optic Distributed Temperature Sensing (DTS) provides thousands of measurements referenced to a single calibration standard at much reduced costs. The aim of this work was to enhance the vertical resolution of Raman scatter DTS measurements up to the centimeter-scale using a novel approach for atmospheric applications: the optical fiber was helically coiled around a meshed fabric. In addition to testing the new fiber geometry, we quantified the measurement uncertainty and demonstrated the benefits of the enhanced-resolution profiles. The fiber-optic cable was coiled around a hollow column consisting of white reinforcing fabric supported by plexiglass rings every meter. Data from two columns of this type were collected for 47 days to measure air temperature vertically over 3.0 and 5.1 m over a gently inclined meadow and over and in a small lake, respectively. Both profiles had a vertical resolution of 1 cm in the lower section near the surface and 5 cm in the upper section with an along-fiber instrument-specific averaging of 1.0 m and a temporal resolution of 30 s. Measurement uncertainties, especially from conduction between reinforcing fabric and fiber-optic cable, were estimated by modeling the fiber temperature via a detailed energy balance approach. Air temperature, wind velocity and radiation components were needed as input data and measured separately. The temperature profiles revealed valuable details, especially in the lowest 1 m above surface. This was best demonstrated for nighttime observations when artefacts due to solar heating did not occur. For example, the dynamics of a cold air layer was detected in a clear night

  1. Distributions of air pollutants associated with oil and natural gas development measured in the Upper Green River Basin of Wyoming

    Directory of Open Access Journals (Sweden)

    R.A. Field

    2015-10-01

    Full Text Available Abstract Diffusive sampler monitoring techniques were employed during wintertime studies from 2009 to 2012 to assess the spatial distribution of air pollutants associated with the Pinedale Anticline and Jonah Field oil and natural gas (O&NG developments in the Upper Green River Basin, Wyoming. Diffusive sampling identified both the extent of wintertime ozone (O3 episodes and the distributions of oxides of nitrogen (NOx, and a suite of 13 C5+ volatile organic compounds (VOC, including BTEX (benzene, toluene, ethylbenzene and xylene isomers, allowing the influence of different O&NG emission sources to be determined. Concentration isopleth mapping of both diffusive sampler and continuous O3 measurements show the importance of localized production and advective transport. As for O3, BTEX and NOx mixing ratios within O&NG development areas were elevated compared to background levels, with localized hotspots also evident. One BTEX hotspot was related to an area with intensive production activities, while a second was located in an area influenced by emissions from a water treatment and recycling facility. Contrastingly, NOx hotspots were at major road intersections with relatively high traffic flows, indicating influence from vehicular emissions. Comparisons of observed selected VOC species ratios at a roadside site in the town of Pinedale with those measured in O&NG development areas show that traffic emissions contribute minimally to VOCs in these latter areas. The spatial distributions of pollutant concentrations identified by diffusive sampling techniques have potential utility for validation of emission inventories that are combined with air quality modeling.

  2. Longitudinal development of air-shower electrons studied from the arrival time distributions of atmospheric Cerenkov light measured at 5200 m above sea level

    International Nuclear Information System (INIS)

    Inoue, N.; Kaneko, T.; Yoshii, H.

    1985-01-01

    The longitudinal development of electrons in extensive air showers before the maximum has been studied by measuring the arrival time distributions of atmospheric Cerenkov light from air showers, with primary energies in the range 6 x 10 15 to 2 x 10 17 eV, in the Chacaltaya air-shower array. These arrival time distributions are consistent with those calculated using a model of particle interactions which contain Feynman scaling in the fragmentation region, an Esup(1/2) multiplicity law in the pionisation region and a rising cross section for primary protons. Such a model also reproduces the arrival time distributions of Cerenkov light measured in the Akeno air-shower array as described in the preceding paper, which implies a very fast development before the maximum and a slow development after the maximum. (author)

  3. The aerosol distribution in Europe derived with the Community Multiscale Air Quality (CMAQ) model: comparison to near surface in situ and sunphotometer measurements

    OpenAIRE

    Matthias , V.

    2008-01-01

    The aerosol distribution in Europe was simulated with the Community Multiscale Air Quality (CMAQ) model system version 4.5 for the years 2000 and 2001. The results were compared with daily averages of PM10 measurements taken in the framework of EMEP and with aerosol optical depth (AOD) values measured within AERONET. The modelled total aerosol mass is typically about 30–60% lower than the corresponding measurements. However a comparison of the chemical composition of th...

  4. Comparison between Different Air Distribution Systems

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    The aim of an air conditioning system is to remove excess heat in a room and replace room air with fresh air to obtain a high air quality. It is not sufficient to remove heat and contaminated air, it is also necessary to distribute and control the air movement in the room to create thermal comfort...... in the occupied zone. Most air distribution systems are based on mixing ventilation with ceiling or wall-mounted diffusers or on displacement ventilation with wall-mounted low velocity diffusers. New principles for room air distribution were introduced during the last decades, as the textile terminals mounted...... in the ceiling and radial diffusers with swirling flow also mounted in the ceiling. This paper addresses five air distribution systems in all, namely mixing ventilation from a wallmounted terminal, mixing ventilation from a ceiling-mounted diffuser, mixing ventilation from a ceiling-mounted diffuser...

  5. The aerosol distribution in Europe derived with the Community Multiscale Air Quality (CMAQ model: comparison to near surface in situ and sunphotometer measurements

    Directory of Open Access Journals (Sweden)

    V. Matthias

    2008-09-01

    Full Text Available The aerosol distribution in Europe was simulated with the Community Multiscale Air Quality (CMAQ model system version 4.5 for the years 2000 and 2001. The results were compared with daily averages of PM10 measurements taken in the framework of EMEP and with aerosol optical depth (AOD values measured within AERONET. The modelled total aerosol mass is typically about 30–60% lower than the corresponding measurements. However a comparison of the chemical composition of the aerosol revealed a considerably better agreement between the modelled and the measured aerosol components for ammonium, nitrate and sulfate, which are on average only 15–20% underestimated. Sligthly worse agreement was determined for sea salt, that was only avaliable at two sites. The largest discrepancies result from the aerosol mass which was not chemically specified by the measurements. The agreement between measurements and model is better in winter than in summer. The modelled organic aerosol mass is higher in summer than in winter but it is significantly underestimated by the model. This could be one of the main reasons for the discrepancies between measurements and model results. The other is that primary coarse particles are underestimated in the emissions. The probability distribution function of the PM10 measurements follows a log-normal distribution at most sites. The model is only able to reproduce this distribution function at non-coastal low altitude stations. The AOD derived from the model results is 20–70% lower than the values observed within AERONET. This is mainly attributed to the missing aerosol mass in the model. The day-to-day variability of the AOD and the log-normal distribution functions are quite well reproduced by the model. The seasonality on the other hand is underestimated by the model results because better agreement is achieved in winter.

  6. Longitudinal development of muons in large air showers studies from the arrival time distributions measured at 900m above sea level

    Science.gov (United States)

    Kakimoto, F.; Tsuchimoto, I.; Enoki, T.; Suga, K.; Nishi, K.

    1985-01-01

    The arrival time distributions of muons with energies above 1.0GeV and 0.5GeV have been measured in the Akeno air-shower array to study the longitudinal development of muons in air showers with primary energies in the range 10 to the 17th power to 10 to the 18th power ev. The average rise times of muons with energies above 1.0GeV at large core distances are consistent with those expected from very high multiplicity models and, on the contrary, with those expected from the low multiplicity models at small core distances. This implies that the longitudinal development at atmospheric depth smaller than 500 cm square is very fast and that at larger atmospheric depths is rather slow.

  7. Strategy Guideline. Compact Air Distribution Systems

    Energy Technology Data Exchange (ETDEWEB)

    Burdick, Arlan [IBACOS, Inc., Pittsburgh, PA (United States)

    2013-06-01

    This guideline discusses the benefits and challenges of using a compact air distribution system to handle the reduced loads and reduced air volume needed to condition the space within an energy efficient home. The decision criteria for a compact air distribution system must be determined early in the whole-house design process, considering both supply and return air design. However, careful installation of a compact air distribution system can result in lower material costs from smaller equipment, shorter duct runs, and fewer outlets; increased installation efficiencies, including ease of fitting the system into conditioned space; lower loads on a better balanced HVAC system, and overall improved energy efficiency of the home.

  8. Aerosol particle measurements at three stationary sites in the megacity of Paris during summer 2009: meteorology and air mass origin dominate aerosol particle composition and size distribution

    Directory of Open Access Journals (Sweden)

    F. Freutel

    2013-01-01

    Full Text Available During July 2009, a one-month measurement campaign was performed in the megacity of Paris. Amongst other measurement platforms, three stationary sites distributed over an area of 40 km in diameter in the greater Paris region enabled a detailed characterization of the aerosol particle and gas phase. Simulation results from the FLEXPART dispersion model were used to distinguish between different types of air masses sampled. It was found that the origin of air masses had a large influence on measured mass concentrations of the secondary species particulate sulphate, nitrate, ammonium, and oxygenated organic aerosol measured with the Aerodyne aerosol mass spectrometer in the submicron particle size range: particularly high concentrations of these species (about 4 μg m−3, 2 μg m−3, 2 μg m−3, and 7 μg m−3, respectively were measured when aged material was advected from continental Europe, while for air masses originating from the Atlantic, much lower mass concentrations of these species were observed (about 1 μg m−3, 0.2 μg m−3, 0.4 μg m−3, and 1–3 μg m−3, respectively. For the primary emission tracers hydrocarbon-like organic aerosol, black carbon, and NOx it was found that apart from diurnal source strength variations and proximity to emission sources, local meteorology had the largest influence on measured concentrations, with higher wind speeds leading to larger dilution and therefore smaller measured concentrations. Also the shape of particle size distributions was affected by wind speed and air mass origin. Quasi-Lagrangian measurements performed under connected flow conditions between the three stationary sites were used to estimate the influence of the Paris emission plume onto its surroundings, which was found to be rather small. Rough estimates for the impact of the Paris emission plume on the suburban areas can be

  9. Strategy Guideline: Compact Air Distribution Systems

    Energy Technology Data Exchange (ETDEWEB)

    Burdick, A.

    2013-06-01

    This Strategy Guideline discusses the benefits and challenges of using a compact air distribution system to handle the reduced loads and reduced air volume needed to condition the space within an energy efficient home. Traditional systems sized by 'rule of thumb' (i.e., 1 ton of cooling per 400 ft2 of floor space) that 'wash' the exterior walls with conditioned air from floor registers cannot provide appropriate air mixing and moisture removal in low-load homes. A compact air distribution system locates the HVAC equipment centrally with shorter ducts run to interior walls, and ceiling supply outlets throw the air toward the exterior walls along the ceiling plane; alternatively, high sidewall supply outlets throw the air toward the exterior walls. Potential drawbacks include resistance from installing contractors or code officials who are unfamiliar with compact air distribution systems, as well as a lack of availability of low-cost high sidewall or ceiling supply outlets to meet the low air volumes with good throw characteristics. The decision criteria for a compact air distribution system must be determined early in the whole-house design process, considering both supply and return air design. However, careful installation of a compact air distribution system can result in lower material costs from smaller equipment, shorter duct runs, and fewer outlets; increased installation efficiencies, including ease of fitting the system into conditioned space; lower loads on a better balanced HVAC system, and overall improved energy efficiency of the home.

  10. Pin-photodiode array for the measurement of fan-beam energy and air kerma distributions of X-ray CT scanners.

    Science.gov (United States)

    Haba, Tomonobu; Koyama, Shuji; Aoyama, Takahiko; Kinomura, Yutaka; Ida, Yoshihiro; Kobayashi, Masanao; Kameyama, Hiroshi; Tsutsumi, Yoshinori

    2016-07-01

    Patient dose estimation in X-ray computed tomography (CT) is generally performed by Monte Carlo simulation of photon interactions within anthropomorphic or cylindrical phantoms. An accurate Monte Carlo simulation requires an understanding of the effects of the bow-tie filter equipped in a CT scanner, i.e. the change of X-ray energy and air kerma along the fan-beam arc of the CT scanner. To measure the effective energy and air kerma distributions, we devised a pin-photodiode array utilizing eight channels of X-ray sensors arranged at regular intervals along the fan-beam arc of the CT scanner. Each X-ray sensor consisted of two plate type of pin silicon photodiodes in tandem - front and rear photodiodes - and of a lead collimator, which only allowed X-rays to impinge vertically to the silicon surface of the photodiodes. The effective energy of the X-rays was calculated from the ratio of the output voltages of the photodiodes and the dose was calculated from the output voltage of the front photodiode using the energy and dose calibration curves respectively. The pin-photodiode array allowed the calculation of X-ray effective energies and relative doses, at eight points simultaneously along the fan-beam arc of a CT scanner during a single rotation of the scanner. The fan-beam energy and air kerma distributions of CT scanners can be effectively measured using this pin-photodiode array. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  11. The "Family Tree" of Air Distribution Systems

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    2011-01-01

    In this paper all total volume air distribution principles are addressed based on discussions of air flow pattern in a room with heat sources giving a cooling load. The supply and exhaust air openings are considered to have different locations and sizes in the room, and it is possible to show tha...... conditions which are not used for air distribution in general. A number of experiments with different air distribution systems are addressed, and they illustrate the behaviour at the different conditions discussed in the paper....... that all the known types of air distribution systems are interconnected in a “family tree”. The influence of supplied momentum flow versus buoyancy forces is discussed, and geometries for high ventilation effectiveness are indicated as well as geometries for fully mixed flow. The paper will also show......In this paper all total volume air distribution principles are addressed based on discussions of air flow pattern in a room with heat sources giving a cooling load. The supply and exhaust air openings are considered to have different locations and sizes in the room, and it is possible to show...

  12. Diffuse Ceiling Inlet Systems and the Room Air Distribution

    DEFF Research Database (Denmark)

    Nielsen, Peter V.; Jensen, Rasmus Lund; Rong, Li

    2010-01-01

    A diffuse ceiling inlet system is an air distribution system which is supplying the air through the whole ceiling. The system can remove a large heat load without creating draught in the room. The paper describes measurements in the case of both cooling and heating, and CFD predictions are given...

  13. CFD Simulation of Air Velocity Distribution in Occupied Livestock Buildings

    DEFF Research Database (Denmark)

    Svidt, Kjeld; Zhang, G.; Bjerg, B.

    In modem livestock buildings the design of the ventilation systems is important in order to obtain good air distribution. The use of Computational Fluid Dynamics for predicting the air flow and air quality makes it possible to include the effect of room geometry, equipment and occupants in the de......In modem livestock buildings the design of the ventilation systems is important in order to obtain good air distribution. The use of Computational Fluid Dynamics for predicting the air flow and air quality makes it possible to include the effect of room geometry, equipment and occupants....... In this study laboratory measurements in a ventilated test room with "pig simulators" are compared with CFD-simulations....

  14. Air distribution and ventilation effectiveness in an occupied room heated by warm air

    DEFF Research Database (Denmark)

    Krajcik, Michal; Simone, Angela; Olesen, Bjarne W.

    2012-01-01

    and at different simulated outside conditions, internal heat gains and air change rates. Floor heating was also simulated and compared with the warm air heating system. Vertical air temperature profiles, air velocity profiles and equivalent temperatures were derived in order to describe the thermal environment...... floor heating system was simulated, the cooler ventilation air introduced to the room mixed well and created uniform conditions with a ventilation effectiveness of about 1.......Air distribution, ventilation effectiveness and thermal environment were experimentally studied in a simulated room in a low-energy building heated and ventilated by warm air supplied by a mixing ventilation system. Measurements were performed for various positions of the air terminal devices...

  15. Applications of air ion measurement in environmental diagnostics

    International Nuclear Information System (INIS)

    Tammet, H.

    1996-01-01

    The present paper is dealing with the methods employing the measuring of naturally created air ions. The amount and mobility distribution of these ions offer hidden information about air pollution. On the other hand, the natural air ions are active in some environmental processes and they should be considered as an immediate environmental factor

  16. Mathematical Models for Room Air Distribution

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    1982-01-01

    A number of different models on the air distribution in rooms are introduced. This includes the throw model, a model on penetration length of a cold wall jet and a model for maximum velocity in the dimensioning of an air distribution system in highly loaded rooms and shows that the amount of heat...... removed from the room at constant penetration length is proportional to the cube of the velocities in the occupied zone. It is also shown that a large number of diffusers increases the amount of heat which may be removed without affecting the thermal conditions. Control strategies for dual duct and single...... duct systems are given and the paper is concluded by mentioning a computer-based prediction method which gives the velocity and temperature distribution in the whole room....

  17. Mathematical Models for Room Air Distribution - Addendum

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    1982-01-01

    A number of different models on the air distribution in rooms are introduced. This includes the throw model, a model on penetration length of a cold wall jet and a model for maximum velocity in the dimensioning of an air distribution system in highly loaded rooms and shows that the amount of heat...... removed from the room at constant penetration length is proportional to the cube of the velocities in the occupied zone. It is also shown that a large number of diffusers increases the amount of heat which may be removed without affecting the thermal conditions. Control strategies for dual duct and single...... duct systems are given and the paper is concluded by mentioning a computer-based prediction method which gives the velocity and temperature distribution in the whole room....

  18. Measurement of air distribution and void fraction of an upwards air–water flow using electrical resistance tomography and a wire-mesh sensor

    International Nuclear Information System (INIS)

    Olerni, Claudio; Jia, Jiabin; Wang, Mi

    2013-01-01

    Measurements on an upwards air–water flow are reported that were obtained simultaneously with a dual-plane electrical resistance tomograph (ERT) and a wire-mesh sensor (WMS). The ultimate measurement target of both ERT and WMS is the same, the electrical conductivity of the medium. The ERT is a non-intrusive device whereas the WMS requires a net of wires that physically crosses the flow. This paper presents comparisons between the results obtained simultaneously from the ERT and the WMS for evaluation and calibration of the ERT. The length of the vertical testing pipeline section is 3 m with an internal diameter of 50 mm. Two distinct sets of air–water flow rate scenarios, bubble and slug regimes, were produced in the experiments. The fast impedance camera ERT recorded the data at an approximate time resolution of 896 frames per second (fps) per plane in contrast with the 1024 fps of the wire-mesh sensor WMS200. The set-up of the experiment was based on well established knowledge of air–water upwards flow, particularly the specific flow regimes and wall peak effects. The local air void fraction profiles and the overall air void fraction were produced from two systems to establish consistency for comparison of the data accuracy. Conventional bulk flow measurements in air mass and electromagnetic flow metering, as well as pressure and temperature, were employed, which brought the necessary calibration to the flow measurements. The results show that the profiles generated from the two systems have a certain level of inconsistency, particularly in a wall peak and a core peak from the ERT and WMS respectively, whereas the two tomography instruments achieve good agreement on the overall air void fraction for bubble flow. For slug flow, when the void fraction is over 30%, the ERT underestimates the void fraction, but a linear relation between ERT and WMS is still observed. (paper)

  19. The measurement of low air flow velocities

    NARCIS (Netherlands)

    Aghaei, A.; Mao, X.G.; Zanden, van der A.J.J.; Schaik, W.H.J.; Hendriks, N.A.

    2005-01-01

    Air flow velocity is measured with an acoustic sensor, which can be used especially for measuring low air flow velocities as well as the temperature of the air simultaneously. Two opposite transducers send a sound pulse towards each other. From the difference of the transit times, the air flow

  20. Geometric effects in alpha particle detection from distributed air sources

    International Nuclear Information System (INIS)

    Gil, L.R.; Leitao, R.M.S.; Marques, A.; Rivera, A.

    1994-08-01

    Geometric effects associated to detection of alpha particles from distributed air sources, as it happens in Radon and Thoron measurements, are revisited. The volume outside which no alpha particle may reach the entrance window of the detector is defined and determined analytically for rectangular and cylindrical symmetry geometries. (author). 3 figs

  1. Next Generation Air Measurement Technologies Fact Sheet

    Science.gov (United States)

    EPA is advancing lower cost and portable air measurement technology to enhance monitoring capabilities for complying with the National Ambient Air Quality Standards. The technology is providing mobile and stationary real-time measurement capabilities.

  2. Air brake-dynamometer accurately measures torque

    Science.gov (United States)

    1965-01-01

    Air brake-dynamometer assembly combines the principles of the air turbine and the air pump to apply braking torque. The assembly absorbs and measures power outputs of rotating machinery over a wide range of shaft speeds. It can also be used as an air turbine.

  3. Quantitative measurements of air-fuel mixture distribution in a cylinder using LIF; LIF ni yoru tonai kongoki nodo no teiryoteki keisoku

    Energy Technology Data Exchange (ETDEWEB)

    Kato, S; Kadoi, N [Subaru Research Center, Tokyo (Japan)

    1997-10-01

    It is necessary to understand the mechanisms of mixture formation in a cylinder to improve engine performance, especially for a gasoline direct injection engine. In this study, a quantitative air-fuel mixture measurement technique using PLIF was developed. Across a laser sheet, a transparent liner was placed between two calibration cells which increased the reliability of fuel concentration. This technique was applied to gasoline direct injection engine to clarify the effect of injection timing on stratified charged mixture. 4 refs., 6 figs., 3 tabs.

  4. Gap in air pollution reduction measures

    International Nuclear Information System (INIS)

    Kamphuis, E.; Spijker, E.

    2006-01-01

    The air quality dossier in the Netherlands requires drastic cleaning of the vehicles fleet. However, the present measures are too much focused on the installation and use of soot filters. Other options to improve the air quality are discussed [nl

  5. Disruptive Innovation in Air Measurement Technology: Reality ...

    Science.gov (United States)

    This presentation is a big picture overview on the changing state of air measurement technology in the world, with a focus on the introduction of low-cost sensors into the market place. The presentation discusses how these new technologies may be a case study in disruptive innovation for the air pollution measurement field. The intended audience is primarily those with experience in air pollution measurement methods, but much of the talk is accessible to the general public. This is a keynote presentation on emerging air monitoring technology, to be provided at the AWMA measurements conference in March, 2016.

  6. Air Monitoring, Measuring, and Emissions Research

    Science.gov (United States)

    Measurement research is advancing the ability to determine the composition of sources of air pollution, conduct exposure assessments, improve monitoring capabilities and support public health research.

  7. Counting systems characterization for air activity measurements

    International Nuclear Information System (INIS)

    Vijayakumar, B.; Balamurugan, M.; Ravi, P.M.

    2018-01-01

    Air activity measurements are carried out continuously at all the nuclear power plant (NPP) sites both during pre-operational phase and also during operation of nuclear facility. These measurements provide a trend line for the background air activity in the surrounding environments of an operating NPP. Any increase in air activity over the benchmark level becomes very handy to investigate the releases from the station and to give feedback to the operators of NPP about the prevailing air activity levels and their correlation to the plant releases. This paper compiles the results obtained for air filter samples using different counters operating in GM region and also plastic scintillators

  8. Development of a distributed air pollutant dry deposition modeling framework

    International Nuclear Information System (INIS)

    Hirabayashi, Satoshi; Kroll, Charles N.; Nowak, David J.

    2012-01-01

    A distributed air pollutant dry deposition modeling system was developed with a geographic information system (GIS) to enhance the functionality of i-Tree Eco (i-Tree, 2011). With the developed system, temperature, leaf area index (LAI) and air pollutant concentration in a spatially distributed form can be estimated, and based on these and other input variables, dry deposition of carbon monoxide (CO), nitrogen dioxide (NO 2 ), sulfur dioxide (SO 2 ), and particulate matter less than 10 microns (PM10) to trees can be spatially quantified. Employing nationally available road network, traffic volume, air pollutant emission/measurement and meteorological data, the developed system provides a framework for the U.S. city managers to identify spatial patterns of urban forest and locate potential areas for future urban forest planting and protection to improve air quality. To exhibit the usability of the framework, a case study was performed for July and August of 2005 in Baltimore, MD. - Highlights: ► A distributed air pollutant dry deposition modeling system was developed. ► The developed system enhances the functionality of i-Tree Eco. ► The developed system employs nationally available input datasets. ► The developed system is transferable to any U.S. city. ► Future planting and protection spots were visually identified in a case study. - Employing nationally available datasets and a GIS, this study will provide urban forest managers in U.S. cities a framework to quantify and visualize urban forest structure and its air pollution removal effect.

  9. Helium Tracer Tests for Assessing Air Recovery and Air Distribution During In Situ Air Sparging

    National Research Council Canada - National Science Library

    Johnson, Richard

    2001-01-01

    ...) systems for capturing contaminant vapors liberated by in situ air sparging (IAS). The tracer approach is simple to conduct and provides more direct and reliable measures than the soil-gas pressure approach...

  10. Measuring Air Force Contracting Customer Satisfaction

    Science.gov (United States)

    2015-12-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA MBA PROFESSIONAL REPORT MEASURING AIR FORCE CONTRACTING CUSTOMER SATISFACTION ...... satisfaction elements should be included in a standardized tool that measures the level of customer satisfaction for AF Contracting’s external and

  11. Air shower measurements with LOFAR

    NARCIS (Netherlands)

    Horneffer, A.; Bähren, L.; Buitink, S.; Falcke, H.; Hörandel, J.R.; Kuijpers, J.; Lafebre, S.; Nigl, A.; Scholten, O.; Singh, K.

    2009-01-01

    Air showers from cosmic rays emit short, intense radio pulses. The Low Frequency Array (LOFAR) is a new radio telescope, that is being built in the Netherlands and Europe. Designed primarily as a radio interferometer, the core of LOFAR will have a high density of radio antennas, which will be

  12. The arrival time distribution of muons in extensive air showers

    International Nuclear Information System (INIS)

    Van der Walt, D.J.

    1984-01-01

    An experiment was done to investigate the lateral dependence of the muon arrival time distribution in extensive air showers at small core distances. In the present experiment the muon arrival time distribution was investigated by measuring the relative arrival times between single muons in five fast Cerenkov detectors beneath 500g/cm 2 of concrete and at an atmospheric depth of 880g/cm 2 . It is shown that, although it is not possible to determine the arrival time distribution as such, it is possible to interpret the relative arrival times between muons in terms of the differences between the order statistics of a sample drawn from the arrival time distribution. The relationship between the arrival time distribution of muons relative to the first detected muon and the muon arrival time distribution is also derived. It was found that the dispersion of the muon arrival time distribution does not increase significantly with increasing core distance between 10m and 60m from the core. A comparison with theoretical distributions obtained from model calculations for proton initiated showers indicate that 1. the mean delay of muons with respect to the first detected muon is significantly larger than that expected from the model and 2. the observed dispersion is also significantly larger than the predicted dispersion for core distances between 10m and 60m

  13. The Contaminant Distribution in a Ventilated Room with Different Air Terminal Devices

    DEFF Research Database (Denmark)

    Heiselberg, Per; Nielsen, Peter V.

    The room ventilation is investigated for three different air terminal devices under isothermal conditions. Velocity distribution in the occupied zone is measured for each air terminal device at different air exchange rates. The maximum air exchange rate is determined on the base of both the throw...... of the jets and the comfort requirements applied to measured air velocities in the occupied zone. Normalized concentration distribution in the test room is determined along a vertical line through the middle of the room as a function of the air exchange rate and the density of the tracer gas. The relative...... ventilation efficiency, , based on the room average concentration is also determined as a function of the air exchange rate and the density of the tracer gas. The influence from the position of the return opening on the relative ventilation efficiency is found for one air terminal device....

  14. Some measurements of ambient air pollution

    International Nuclear Information System (INIS)

    Memon, H.R.; Memon, A.A.; Behan, M.Y.

    1999-01-01

    Ambient air pollution arising from different sources in Karachi and its surroundings has been studied. The urban centres like Karachi are mostly confronted with eye-irritation, reduce visibility, heart-diseases, nervous disorder, smog and other unpleasant experiences. In this paper quantitative estimations of some air-pollutants such as sulphur dioxide, carbon monoxide, oxides of nitrogen, chlorine and particular matters are presented with their hazardous effects. The remedial measures for the control of major air emissions are also discussed. (author)

  15. Thermal comfort and indoor air quality in rooms with integrated personalized ventilation and under-floor air distribution systems

    DEFF Research Database (Denmark)

    Li, Ruixin; Sekhar ., S. C.; Melikov, Arsen Krikor

    2011-01-01

    A comprehensive study comprising physical measurements and human subject experiments was conducted to explore the potential for improving occupants' thermal comfort and indoor air quality (IAQ) using a personalized ventilation (PV) system combined with an under-floor air distribution(UFAD) system....... The integrated PV-UFAD system, when operated at relatively high temperature of the air supplied from the UFAD system, provided comfortable cooling of the facial region, improved inhaled air quality, and decreased the risk of "cold feet," which is often reported in rooms with UFAD alone. This article explores...... and a secondary AHU for 100% recirculated air that is supplied through UFAD outlets. Velocity and temperature distribution in the chamber were measured. A breathing thermal manikin was used to measure the heat loss from 26 body segments and to determine the equivalent temperature. The responses of 30 human...

  16. Mixing ventilation guide on mixing air distribution design

    CERN Document Server

    Kandzia, Claudia; Kosonen, Risto; Krikor Melikov, Arsen; Nielsen, Peter Vilhelm

    2013-01-01

    In this guidebook most of the known and used in practice methods for achieving mixing air distribution are discussed. Mixing ventilation has been applied to many different spaces providing fresh air and thermal comfort to the occupants. Today, a design engineer can choose from large selection of air diffusers and exhaust openings.

  17. Measurement of Air Pollutants in the Troposphere

    Science.gov (United States)

    Clemitshaw, Kevin C.

    2011-01-01

    This article describes the principles, applications and performances of methods to measure gas-phase air pollutants that either utilise passive or active sampling with subsequent laboratory analysis or involve automated "in situ" sampling and analysis. It focuses on air pollutants that have adverse impacts on human health (nitrogen…

  18. Experimental verification of air flow rate measurement for representative isokinetic air sampling in ventilation stacks

    International Nuclear Information System (INIS)

    Okruhlica, P.; Mrtvy, M.; Kopecky, Z.

    2009-01-01

    Nuclear facilities are obliged to monitor their discharge's influence on environment. Main monitored factions in NPP's ventilation stacks are usually noble gasses, particulates and iodine. These factions are monitored in air sampled from ventilation stack by means of sampling rosette and bypass followed with on-line measuring monitors and balance sampling devices with laboratory evaluations. Correct air flow rate measurement and representative iso-kinetic air sampling system is essential for physical correct and metrological accurate evaluation of discharge influence on environment. Pairs of measuring sensors (Anemometer, pressure gauge, thermometer and humidity meter) are symmetrically placed in horizontal projection of stack on positions based on measured air flow velocity distribution characteristic, Analogically diameter of sampling rosette nozzles and their placement in the middle of 6 - 7 annuluses are calculated for assurance of representative iso-kinetic sampling. (authors)

  19. Experimental verification of air flow rate measurement for representative isokinetic air sampling in ventilation stacks

    International Nuclear Information System (INIS)

    Okruhlica, P.; Mrtvy, M.; Kopecky, Z.

    2008-01-01

    Nuclear facilities are obliged to monitor their discharge's influence on environment. Main monitored factions in NPP's ventilation stacks are usually noble gasses, particulates and iodine. These factions are monitored in air sampled from ventilation stack by means of sampling rosette and bypass followed with on-line measuring monitors and balance sampling devices with laboratory evaluations. Correct air flow rate measurement and representative iso-kinetic air sampling system is essential for physical correct and metrological accurate evaluation of discharge influence on environment. Pairs of measuring sensors (Anemometer, pressure gauge, thermometer and humidity meter) are symmetrically placed in horizontal projection of stack on positions based on measured air flow velocity distribution characteristic, Analogically diameter of sampling rosette nozzles and their placement in the middle of 6- 7 annuluses are calculated for assurance of representative iso-kinetic sampling. (authors)

  20. The probability distribution model of air pollution index and its dominants in Kuala Lumpur

    Science.gov (United States)

    AL-Dhurafi, Nasr Ahmed; Razali, Ahmad Mahir; Masseran, Nurulkamal; Zamzuri, Zamira Hasanah

    2016-11-01

    This paper focuses on the statistical modeling for the distributions of air pollution index (API) and its sub-indexes data observed at Kuala Lumpur in Malaysia. Five pollutants or sub-indexes are measured including, carbon monoxide (CO); sulphur dioxide (SO2); nitrogen dioxide (NO2), and; particulate matter (PM10). Four probability distributions are considered, namely log-normal, exponential, Gamma and Weibull in search for the best fit distribution to the Malaysian air pollutants data. In order to determine the best distribution for describing the air pollutants data, five goodness-of-fit criteria's are applied. This will help in minimizing the uncertainty in pollution resource estimates and improving the assessment phase of planning. The conflict in criterion results for selecting the best distribution was overcome by using the weight of ranks method. We found that the Gamma distribution is the best distribution for the majority of air pollutants data in Kuala Lumpur.

  1. Measurement results obtained from air quality monitoring system

    Energy Technology Data Exchange (ETDEWEB)

    Turzanski, P.K.; Beres, R. [Provincial Inspection of Environmental Protection, Cracow (Poland)

    1995-12-31

    An automatic system of air pollution monitoring operates in Cracow since 1991. The organization, assembling and start-up of the network is a result of joint efforts of the US Environmental Protection Agency and the Cracow environmental protection service. At present the automatic monitoring network is operated by the Provincial Inspection of Environmental Protection. There are in total seven stationary stations situated in Cracow to measure air pollution. These stations are supported continuously by one semi-mobile (transportable) station. It allows to modify periodically the area under investigation and therefore the 3-dimensional picture of creation and distribution of air pollutants within Cracow area could be more intelligible.

  2. Physical distributions of radon decay chain activities in air

    International Nuclear Information System (INIS)

    Rolle, R.

    2004-01-01

    The distribution of short-lived radon decay chain activities in air - in time, space and on aerosols - determines their exposure potential and measurement thereof. The radioactive decay constants and flow variables in a flow system combine, yielding activity concentration distributions and ratios of concentrations characteristic of the flow scheme, its source(s) and sink(s). The clock of 'internal' decay constants allows the unraveling of characteristics of the flow scheme from activity concentration measurements of individual members of a decay chain. Basic flow string calculations are shown. These can be assembled to define or simulate concentrations in a single- or multiple-compartment flow network. Response calculations to single- and multiple-step, or continuous changes in sources and sinks yield time-, spatial- and attachment-distributions. For the short-lived 222 Rn and 212 Pb decay chains the decay constants of the shorter-lived progeny in relation to the parent impose air activity ratios on successive chain members. Ratio limits had been used in the past to improve older grab-sampling- or integral gross-alpha measurement procedures for assessing exposure level. Assessment of individual concentrations, ratios and their distributions enables unravelling of dynamic flow systems, with restriction from the range of the parameters of flow and decay. An activity measuring instrument by itself represents a flow system with a response time distribution. Instrument response correction during continuous or quasi-continuous sampling and continuous spectrometric measurement allows far more accurate time-resolved measurement evaluation of continuously varying air concentrations, than previously attainable. Strong diurnal or even shorter (≤ 1 hr) changes probably are the norm in indoor and outdoor air activity concentrations. A mere average response evaluation, as used in steady state instrument calibration, and using less efficient instruments, is usually inadequate

  3. Healthy Buildings and Air Distribution in Rooms

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    Healthy buildings are to a great extent a question of indoor air quality. The processes involved in air quality can be looked upon as a number of links in a chain. Typical links will be emission from building materials, convection and diffusion in the room, local airflow around a person, personal...... exposure and at last the effect of the air quality on the occupant. The best results will obviously be obtained by using building materials with low emission. However, there will always exist some emission and the ventilation will consequently be an important link....

  4. Diffusion air effects on the soot axial distribution concentration in a premixed acetylene/air flame

    Energy Technology Data Exchange (ETDEWEB)

    Fassani, Fabio Luis; Santos, Alex Alisson Bandeira; Goldstein Junior, Leonardo [Universidade Estadual de Campinas, SP (Brazil). Faculdade de Engenharia Mecanica. Dept. de Engenharia Termica e de Fluidos]. E-mails: fassani@fem.unicamp.br; absantos@fem.unicamp.br; leonardo@fem.unicamp.br; Ferrari, Carlos Alberto [Universidade Estadual de Campinas, SP (Brazil). Inst. de Fisica. Dept. de Eletronica Quantica]. E-mail: ferrari@ifi.unicamp.br

    2000-07-01

    Soot particles are produced during the high temperature pyrolysis or combustion of hydrocarbons. The emission of soot from a combustor, or from a flame, is determined by the competition between soot formation and its oxidation. Several factors affect these processes, including the type of fuel, the air-to-fuel ratio, flame temperature, pressure, and flow pattern. In this paper, the influence of the induced air diffusion on the soot axial distribution concentration in a premixed acetylene/air flame was studied. The flame was generated in a vertical axis burner in which the fuel - oxidant mixture flow was surrounded by a nitrogen discharge coming from the annular region between the burner tube and an external concentric tube. The nitrogen flow provided a shield that protected the flame from the diffusion of external air, enabling its control. The burner was mounted on a step-motor driven, vertical translation table. The use of several air-to-fuel ratios made possible to establish the sooting characteristics of this flame, by measuring soot concentration along the flame height with a non-intrusive laser light absorption technique. (author)

  5. Advanced Strategy Guideline: Air Distribution Basics and Duct Design

    Energy Technology Data Exchange (ETDEWEB)

    Burdick, A.

    2011-12-01

    This report discusses considerations for designing an air distribution system for an energy efficient house that requires less air volume to condition the space. Considering the HVAC system early in the design process will allow adequate space for equipment and ductwork and can result in cost savings. Principles discussed that will maximize occupant comfort include delivery of the proper amount of conditioned air for appropriate temperature mixing and uniformity without drafts, minimization of system noise, the impacts of pressure loss, efficient return air duct design, and supply air outlet placement, as well as duct layout, materials, and sizing.

  6. Online Monitoring System of Air Distribution in Pulverized Coal-Fired Boiler Based on Numerical Modeling

    Science.gov (United States)

    Żymełka, Piotr; Nabagło, Daniel; Janda, Tomasz; Madejski, Paweł

    2017-12-01

    Balanced distribution of air in coal-fired boiler is one of the most important factors in the combustion process and is strongly connected to the overall system efficiency. Reliable and continuous information about combustion airflow and fuel rate is essential for achieving optimal stoichiometric ratio as well as efficient and safe operation of a boiler. Imbalances in air distribution result in reduced boiler efficiency, increased gas pollutant emission and operating problems, such as corrosion, slagging or fouling. Monitoring of air flow trends in boiler is an effective method for further analysis and can help to appoint important dependences and start optimization actions. Accurate real-time monitoring of the air distribution in boiler can bring economical, environmental and operational benefits. The paper presents a novel concept for online monitoring system of air distribution in coal-fired boiler based on real-time numerical calculations. The proposed mathematical model allows for identification of mass flow rates of secondary air to individual burners and to overfire air (OFA) nozzles. Numerical models of air and flue gas system were developed using software for power plant simulation. The correctness of the developed model was verified and validated with the reference measurement values. The presented numerical model for real-time monitoring of air distribution is capable of giving continuous determination of the complete air flows based on available digital communication system (DCS) data.

  7. Online Monitoring System of Air Distribution in Pulverized Coal-Fired Boiler Based on Numerical Modeling

    Directory of Open Access Journals (Sweden)

    Żymełka Piotr

    2017-12-01

    Full Text Available Balanced distribution of air in coal-fired boiler is one of the most important factors in the combustion process and is strongly connected to the overall system efficiency. Reliable and continuous information about combustion airflow and fuel rate is essential for achieving optimal stoichiometric ratio as well as efficient and safe operation of a boiler. Imbalances in air distribution result in reduced boiler efficiency, increased gas pollutant emission and operating problems, such as corrosion, slagging or fouling. Monitoring of air flow trends in boiler is an effective method for further analysis and can help to appoint important dependences and start optimization actions. Accurate real-time monitoring of the air distribution in boiler can bring economical, environmental and operational benefits. The paper presents a novel concept for online monitoring system of air distribution in coal-fired boiler based on real-time numerical calculations. The proposed mathematical model allows for identification of mass flow rates of secondary air to individual burners and to overfire air (OFA nozzles. Numerical models of air and flue gas system were developed using software for power plant simulation. The correctness of the developed model was verified and validated with the reference measurement values. The presented numerical model for real-time monitoring of air distribution is capable of giving continuous determination of the complete air flows based on available digital communication system (DCS data.

  8. 40 CFR 89.414 - Air flow measurement specifications.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Air flow measurement specifications... Emission Test Procedures § 89.414 Air flow measurement specifications. (a) The air flow measurement method... incorporates devices that affect the air flow measurement (such as air bleeds) that result in understated...

  9. Air Distribution in a Room with Ceiling-Mounted Diffusers

    DEFF Research Database (Denmark)

    Nielsen, Peter V.; Heby, Thomas; Moeller-Jensen, Bertil

    2006-01-01

    . The characteristics of the air distribution systems are addressed by analysing the acceptable conditions for the supply flow rate and the temperature difference for the different systems. The paper shows that an air distribution system with ceiling-mounted air terminal units is able to generate comfortable velocity...... with swirling flow generates a flow pattern in the room which is rather uninfluenced by the thermal load. The flow is highly mixed above the occupied zone and the air movement penetrates the occupied zone close to the walls. All systems are tested in the same room with the same heat load consisting of two...... manikins, each sitting at a desk, two pc's and two desk lamps producing a total heat load of 480 W. The design of the air distribution system is in all five cases based on flow elements from the diffuser, a maximum velocity assumption and a critical vertical temperature gradient in the room...

  10. AIR DISTRIBUTION NOISE CONTROL IN CRITICAL AUDITORIUMS.

    Science.gov (United States)

    HOOVER, R.M.

    THE ACHIEVEMENT OF EXTREMELY LOW AIR-CONDITIONING NOISE LEVELS REQUIRED FOR MODERN AUDITORIUMS ARE THE RESULT OF CAREFUL PLANNING AND THOROUGH DETAILING. PROBLEMS FACED AND TECHNIQUES USED IN ARRIVING AT LEVELS AS LOW AS NC-15 FOR A SINGLE SYSTEM SERVING A HALL ARE DESCRIBED. SIX CASE HISTORIES ARE EXAMINED AND THE FOLLOWING OBSERVATIONS ARE…

  11. 40 CFR 92.108 - Intake and cooling air measurements.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Intake and cooling air measurements....108 Intake and cooling air measurements. (a) Intake air flow measurement. Measurement of the flow rate..., the measurement technique shall conform to the following: (1) The air flow measurement method used...

  12. Air flow distribution in and around a single-sided naturally ventilated room

    Energy Technology Data Exchange (ETDEWEB)

    Eftekhari, M.M.; Marjanovic, L.D.; Pinnock, D.J. [Loughborough University (United Kingdom). Dept. of Civil and Building Engineering

    2002-03-01

    The objective of this research is to compare calculated and measured air flow distributions inside a test room which is naturally ventilated. The test room is situated in a relatively sheltered location and to visualise the resultant local wind pattern around the room for all prevailing wind directions, wind tunnel trials were carried out. Both the wind tunnel and full-scale measurements show that the wind direction at the test cell was generally restricted to either a westerly or an easterly direction. To investigate air flow inside the room, the air pressures and velocities across the openings together with indoor air temperature and velocity at four locations and six different levels are measured. The experimental results demonstrate that for both winter and summer the air was entering the test room at bottom and leaving at the top louvre. Separate air flow and thermal modelling programs are used to predict the spatial distribution of the air flow and thermal comfort. The air flow distribution was predicted using a network air flow program. The predicted flow showed similar trends and the simulation results were in agreement with the measured data. An explicit finite-difference thermal modeling simulation package was used to predict the thermal comfort indices.(author)

  13. Advanced Strategy Guideline. Air Distribution Basics and Duct Design

    Energy Technology Data Exchange (ETDEWEB)

    Arlan Burdick

    2011-12-01

    This report discusses considerations for designing an air distribution system for an energy efficient house that requires less air volume to condition the space. Considering the HVAC system early in the design process will allow adequate space for equipment and ductwork and can result in cost savings.

  14. Mixing Ventilation. Guide on mixing air distribution design

    DEFF Research Database (Denmark)

    Kandzia, Claudia; Kosonen, Risto; Melikov, Arsen Krikor

    In this guidebook most of the known and used in practice methods for achieving mixing air distribution are discussed. Mixing ventilation has been applied to many different spaces providing fresh air and thermal comfort to the occupants. Today, a design engineer can choose from large selection...

  15. Evaluation of an improved air distribution system for aircraft cabin

    DEFF Research Database (Denmark)

    Pang, Liping; Xu, Jie; Fang, Lei

    2013-01-01

    An improved air distribution system for aircraft cabin was proposed in this paper. Personalized outlets were introduced and placed at the bottom of the baggage hold. Its ratio of fresh air to recirculation air and the conditioned temperature of different types of inlets were also designed carefully...... to meet the goals of high air quality, thermal comfort and energy saving. Some experiments were conducted to evaluate and compare its performances with two other systems. First the Flow Visualization with Green Laser (FVGL) technology was used to analyze the air flow. The top-in-side bottom-out pattern...... may have the disadvantages of an indirect path to deliver fresh air to passengers, a low fresh air utilization ratio and the potential to widely spreading airborne infectious diseases. The bottom-in-top-out pattern can overcome these disadvantages very well, but it also faces the stratification...

  16. Logistics Supply of the Distributed Air Wing

    Science.gov (United States)

    2014-09-01

    Event Graph The Consumption Process first instantiates the variables . The model follows a conveyor belt pattern, whereby after processing an event...the following problem statement: Design a system of systems and the concept of operations to employ naval air assets in a range of missions to augment...airbases are designed to be set up within three days, utilizing highways as short runways for the Short Take Off Vertical Landing (STOVL) aircraft F

  17. Air conditioning system and component therefore distributing air flow from opposite directions

    Science.gov (United States)

    Obler, H. D.; Bauer, H. B. (Inventor)

    1974-01-01

    The air conditioning system comprises a plurality of separate air conditioning units coupled to a common supply duct such that air may be introduced into the supply duct in two opposite flow directions. A plurality of outlets such as registers or auxiliary or branch ducts communicate with the supply duct and valve means are disposed in the supply duct at at least some of the outlets for automatically channelling a controllable amount of air from the supply duct to the associated outlet regardless of the direction of air flow within the supply duct. The valve means comprises an automatic air volume control apparatus for distribution within the air supply duct into which air may be introduced from two opposite directions. The apparatus incorporates a freely swinging movable vane in the supply duct to automatically channel into the associated outlet only the deflected air flow which has the higher relative pressure.

  18. 40 CFR 89.326 - Engine intake air humidity measurement.

    Science.gov (United States)

    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... type of intake air supply, the humidity measurements must be made within the intake air supply system...

  19. 40 CFR 91.310 - Engine intake air humidity measurement.

    Science.gov (United States)

    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. Air...

  20. Measuring Air Density in the Introductory Lab

    Science.gov (United States)

    Calza, G.; Gratton, L. M.; Lopez-Arias, T.; Oss, S.

    2010-01-01

    The measurement of the mass, or the density, of air can easily be done with very simple materials and offers many interesting phenomena for discussion--buoyancy and its effects being the most obvious but not the only one. Many interesting considerations can be done regarding the behavior of gases, the effect of the external conditions in the…

  1. Measure Guideline: Guide to Attic Air Sealing

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, J.

    2014-09-01

    The Guide to Attic Air Sealing was completed in 2010 and although not in the standard Measure Guideline format, is intended to be a Measure Guideline on Attic Air Sealing. The guide was reviewed during two industry stakeholders meetings held on December 18th, 2009 and January 15th, 2010, and modified based on the comments received. Please do not make comments on the Building America format of this document. The purpose of the Guide to Attic Air Sealing is to provide information and recommendations for the preparation work necessary prior to adding attic insulation. Even though the purpose of this guide is to save energy - health, safety and durability should not be compromised by energy efficiency. Accordingly, combustion safety and ventilation for indoor air quality are addressed first. Durability and attic ventilation then follow. Finally, to maximize energy savings, air sealing is completed prior to insulating. The guide is intended for home remodelers, builders, insulation contractors, mechanical contractors, general contractors who have previously done remodeling and homeowners as a guide to the work that needs to be done.

  2. Measure Guideline: Guide to Attic Air Sealing

    Energy Technology Data Exchange (ETDEWEB)

    Lstiburek, Joseph [Building Science Corporation, Westford, MA (United States)

    2014-09-01

    The purpose of this measure guideline is to provide information and recommendations for the preparation work necessary prior to adding attic insulation. Even though the purpose of this guide is to save energy, health, safety, and durability should not be compromised by energy efficiency. Accordingly, combustion safety and ventilation for indoor air quality are addressed first. Durability and attic ventilation then follow. Finally, to maximize energy savings, air sealing is completed prior to insulating. The guide is intended for home remodelers, builders, insulation contractors, mechanical contractors, general contractors who have previously done remodeling and homeowners as a guide to the work that needs to be done.

  3. 40 CFR 91.309 - Engine intake air temperature measurement.

    Science.gov (United States)

    2010-07-01

    ... measurement. 91.309 Section 91.309 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Provisions § 91.309 Engine intake air temperature measurement. (a) Engine intake air temperature measurement must be made within 100 cm of the air-intake of the engine. The measurement location must be either in...

  4. 40 CFR 91.416 - Intake air flow measurement specifications.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Intake air flow measurement... Procedures § 91.416 Intake air flow measurement specifications. (a) If used, the engine intake air flow measurement method used must have a range large enough to accurately measure the air flow over the engine...

  5. Experimental evaluation of air distribution in mechanically ventilated residential rooms

    DEFF Research Database (Denmark)

    Tomasi, R.; Krajčík, M.; Simone, A.

    2013-01-01

    The effect of low ventilation rates (1 or 0.5 air change per hour) on thermal comfort and ventilation effectiveness was experimentally studied in a simulated residential room equipped with radiant floor heating/cooling and mixing ventilation systems. The tests were performed for various positions...... of supply and extract air terminals and different winter and summer boundary conditions. Vertical air temperature, operative temperature and air velocity profiles were measured in different positions in the room, and equivalent temperatures were derived, in order to characterize thermal comfort. Contaminant...... with unconditioned outdoor air supply, i.e. at the supply air temperatures higher than the room air temperature. Moreover, low floor temperatures were needed to maintain the desired reference temperature in the stratified thermal environment. Mainly in cooling conditions the ventilation effectiveness depended...

  6. Air Distribution Retrofit Strategies for Affordable Housing

    Energy Technology Data Exchange (ETDEWEB)

    Dentz, Jordan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Conlin, Francis [National Renewable Energy Lab. (NREL), Golden, CO (United States); Holloway, Parker [National Renewable Energy Lab. (NREL), Golden, CO (United States); Podorson, David [National Renewable Energy Lab. (NREL), Golden, CO (United States); Varshney, Kapil [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-03-01

    In multifamily and attached buildings, traditional duct sealing methods are often impractical or costly and disruptive because of the difficulty in accessing leakage sites. In this project, two retrofit duct sealing techniques -- manually-applied sealants and injecting a spray sealant, were implemented in several low-rise multi-unit buildings. An analysis on the cost and performance of the two methods are presented. Each method was used in twenty housing units: approximately half of each group of units are single story and the remainder two-story. Results show that duct leakage to the outside was reduced by an average of 59% through the use of manual methods, and by 90% in the units where the injected spray sealant was used. It was found that 73% of the leakage reduction in homes that were treated with injected spray sealant was attributable to the manual sealing done at boots, returns and the air handler. The cost of manually-applying sealant ranged from $275 to $511 per unit and for the injected spray sealant the cost was $700 per unit. Modeling suggests a simple payback of 2.2 years for manual sealing and 4.7 years for the injected spray sealant system. Utility bills were collected for one year before and after the retrofits. Utility bill analysis shows 14% and 16% energy savings using injected spray sealant system and hand sealing procedure respectively in heating season whereas in cooling season, energy savings using injected spray sealant system and hand sealing were both 16%.

  7. Air Distribution Retrofit Strategies for Affordable Housing

    Energy Technology Data Exchange (ETDEWEB)

    Dentz, J. [Advanced Residential Integrated Energy Solutions (ARIES), New York, NY (United States); Conlin, F. [Advanced Residential Integrated Energy Solutions (ARIES), New York, NY (United States); Holloway, Parker [Advanced Residential Integrated Energy Solutions (ARIES), New York, NY (United States); Podorson, David [Advanced Residential Integrated Energy Solutions (ARIES), New York, NY (United States); Varshney, Kapil [Advanced Residential Integrated Energy Solutions (ARIES), New York, NY (United States)

    2014-03-01

    In multifamily and attached buildings, traditional duct sealing methods are often impractical or costly and disruptive because of the difficulty in accessing leakage sites. In this project, two retrofit duct sealing techniques, manually-applied sealants and injecting a spray sealant, were implemented in several low-rise multiunit buildings. An analysis on the cost and performance of the two methods are presented. Each method was used in twenty housing units: approximately half of each group of units are single story and the remainder are two story. Results show that duct leakage to the outside was reduced by an average of 59% through the use of manual methods, and by 90% in the units where the injected spray sealant was used. It was found that 73% of the leakage reduction in homes that were treated with injected spray sealant was attributable to the manual sealing done at boots, returns and the air handler. The cost of manually-applying sealant ranged from $275 to $511 per unit and for the injected spray sealant the cost was $700 per unit. Modeling suggests a simple payback of 2.2 years for manual sealing and 4.7 years for the injected spray sealant system. Utility bills were collected for one year before and after the retrofits. Utility bill analysis shows 14% and 16% energy savings using injected spray sealant system and hand sealing procedure respectively in heating season whereas in cooling season, energy savings using injected spray sealant system and hand sealing were both 16%.

  8. Amine Measurements in Boreal Forest Air

    Science.gov (United States)

    Hemmilä, Marja; Hellén, Heidi; Makkonen, Ulla; Hakola, Hannele

    2015-04-01

    Amines are reactive, volatile bases in the air with a general formula of RNH2, R2NH or R3N. Especially small amines can stabilize sulphuric acid clusters and hence affect nucleation. Amines react rapidly with hydroxyl radical (OH˙) thus affecting oxidative capacity of the atmosphere. The amine concentrations are higher in forest air than in urban air (Hellén et al., 2014), but the sources are not known. In order to get more information concerning amine sources, we conducted a measurement campaign in a boreal forest. At SMEAR II station at Hyytiälä, Southern Finland (61°510'N, 24°170'E, 180 m a.s.l.) The measurements cover seven months, from June to December 2014. For sampling and measuring we used MARGA (The instrument for Measuring AeRosols and Gases in Ambient air) which is an on-line ion chromatograph (IC) connected to a sampling system. The IC component of the MARGA system was coupled to an electrospray ionization quadrupole mass spectrometer (MS) to improve sensitivity of amine measurements. This new set-up enabled amine concentration measurements in ambient air both in aerosol and gas phases with a time resolution of only 1 hour. With MARGA-MS we analysed 7 different amines: monomethylamine (MMA), dimethylamine (DMA), trimethylamine (TMA), ethylamine (EA), diethylamine (DEA), propylamine (PA) and butylamine (BA). In preliminary data-analysis we found out, that in June and July most of the measured amines were in gas phase, and particle phase amine concentrations were mostly under detection limits (<1.7 pptv). In June the gaseous amine concentrations were higher than in July. The measured concentrations of gaseous amines followed temperature variation, which could indicate that amines are produced and emitted from the environment or re-emitted from the surfaces as temperature rises after deposition during night-time. All measured amines had similar diurnal variation with maxima during afternoon and minima during night. Results from other months will also

  9. Spatial distribution of emissions to air - the SPREAD model

    Energy Technology Data Exchange (ETDEWEB)

    Plejdrup, M S; Gyldenkaerne, S

    2011-04-15

    The National Environmental Research Institute (NERI), Aarhus University, completes the annual national emission inventories for greenhouse gases and air pollutants according to Denmark's obligations under international conventions, e.g. the climate convention, UNFCCC and the convention on long-range transboundary air pollution, CLRTAP. NERI has developed a model to distribute emissions from the national emission inventories on a 1x1 km grid covering the Danish land and sea territory. The new spatial high resolution distribution model for emissions to air (SPREAD) has been developed according to the requirements for reporting of gridded emissions to CLRTAP. Spatial emission data is e.g. used as input for air quality modelling, which again serves as input for assessment and evaluation of health effects. For these purposes distributions with higher spatial resolution have been requested. Previously, a distribution on the 17x17 km EMEP grid has been set up and used in research projects combined with detailed distributions for a few sectors or sub-sectors e.g. a distribution for emissions from road traffic on 1x1 km resolution. SPREAD is developed to generate improved spatial emission data for e.g. air quality modelling in exposure studies. SPREAD includes emission distributions for each sector in the Danish inventory system; stationary combustion, mobile sources, fugitive emissions from fuels, industrial processes, solvents and other product use, agriculture and waste. This model enables generation of distributions for single sectors and for a number of sub-sectors and single sources as well. This report documents the methodologies in this first version of SPREAD and presents selected results. Further, a number of potential improvements for later versions of SPREAD are addressed and discussed. (Author)

  10. Spatial distribution of emissions to air - the SPREAD model

    Energy Technology Data Exchange (ETDEWEB)

    Plejdrup, M.S.; Gyldenkaerne, S.

    2011-04-15

    The National Environmental Research Institute (NERI), Aarhus University, completes the annual national emission inventories for greenhouse gases and air pollutants according to Denmark's obligations under international conventions, e.g. the climate convention, UNFCCC and the convention on long-range transboundary air pollution, CLRTAP. NERI has developed a model to distribute emissions from the national emission inventories on a 1x1 km grid covering the Danish land and sea territory. The new spatial high resolution distribution model for emissions to air (SPREAD) has been developed according to the requirements for reporting of gridded emissions to CLRTAP. Spatial emission data is e.g. used as input for air quality modelling, which again serves as input for assessment and evaluation of health effects. For these purposes distributions with higher spatial resolution have been requested. Previously, a distribution on the 17x17 km EMEP grid has been set up and used in research projects combined with detailed distributions for a few sectors or sub-sectors e.g. a distribution for emissions from road traffic on 1x1 km resolution. SPREAD is developed to generate improved spatial emission data for e.g. air quality modelling in exposure studies. SPREAD includes emission distributions for each sector in the Danish inventory system; stationary combustion, mobile sources, fugitive emissions from fuels, industrial processes, solvents and other product use, agriculture and waste. This model enables generation of distributions for single sectors and for a number of sub-sectors and single sources as well. This report documents the methodologies in this first version of SPREAD and presents selected results. Further, a number of potential improvements for later versions of SPREAD are addressed and discussed. (Author)

  11. Measuring the distribution of spitefulness.

    Directory of Open Access Journals (Sweden)

    Erik O Kimbrough

    Full Text Available Spiteful, antisocial behavior may undermine the moral and institutional fabric of society, producing disorder, fear, and mistrust. Previous research demonstrates the willingness of individuals to harm others, but little is understood about how far people are willing to go in being spiteful (relative to how far they could have gone or their consistency in spitefulness across repeated trials. Our experiment is the first to provide individuals with repeated opportunities to spitefully harm anonymous others when the decision entails zero cost to the spiter and cannot be observed as such by the object of spite. This method reveals that the majority of individuals exhibit consistent (non-spitefulness over time and that the distribution of spitefulness is bipolar: when choosing whether to be spiteful, most individuals either avoid spite altogether or impose the maximum possible harm on their unwitting victims.

  12. Sodium flow distribution test of the air cooler tubes

    International Nuclear Information System (INIS)

    Uchida, Hiroyuki; Ohta, Hidehisa; Shimazu, Hisashi

    1980-01-01

    In the heat transfer tubes of the air cooler which is installed in the auxiliary core cooling system of the fast breeder prototype plant reactor ''Monju'', sodium freezing may be caused by undercooling the sodium induced by an extremely unbalanced sodium flow in the tubes. Thus, the sodium flow distribution test of the air cooler tubes was performed to examine the flow distribution of the tubes and to estimate the possibility of sodium freezing in the tubes. This test was performed by using a one fourth air cooler model installed in the water flow test facility. As the test results show, the flow distribution from the inlet header to each tube is almost equal at any operating condition, that is, the velocity deviation from normalized mean velocity is less than 6% and sodium freezing does not occur up to 250% air velocity deviation at stand-by condition. It was clear that the proposed air cooler design for the ''Monju'' will have a good sodium flow distribution at any operating condition. (author)

  13. Air quality measurements for site characterization

    International Nuclear Information System (INIS)

    Carter, M.W.; Conklin, W.C.

    1982-01-01

    Effective and timely site characterization is an important part of selecting a site for low-level waste disposal. Parameters measured can be compared with pertinent regulatory requirements, used for a reference base, helpful in evaluating environmental impacts, utilized in documenting changes in control programs, of value in modeling studies and other data uses, and beneficial in providing relevant sampling and methodology training. This paper will focus on specific air quality measurements which should be an inherent part of the site characterization program. The program is designed to measure, quantify, and identify contributions from site uses (operational procedures), atmospheric fallout, natural radioactivity, and vicinity and regional applications of radionuclides. The recommended air quality measurements program will be described in association with a reference site developd by the US Nuclear Regulatory Commission. Particular attention will be devoted to the type and quality of information which is needed, the scope of sampling and measurements, the frequency of measurements, locations and numbers of sampling stations, the period of time needed for site characterization, and the proper uses of the information once it has been obtained. Adequate characterization of the site will be most important in final site selection and in the operation of the site as to periodically assessing environmental impacts and helping guide any remedial control efforts designed to meet regulatory requirements

  14. Air Pollutant Distribution and Mesoscale Circulation Systems During Escompte

    Science.gov (United States)

    Kottmeier, Ch.; Kalthoff, N.; Corsmeier, U.; Robin, D.; Thürauf, J.; Hofherr, T.; Hasel, M.

    The distribution of pollutants observed with an Dornier 128 instrumented aircraft and from AIRMARAIX ground stations during one day of the Escompte experiment (June 25, 2001) is analysed in relation to the mesoscale wind systems and vertical mixing from aircraft and radiosonde data. The ESCOMPTE-experiment (http://medias.obs- mip.fr/escompte) was carried out in June and July 2001 in the urban area of Marseille and its rural surroundings to investigate periods with photosmog conditions. The over- all aim is to produce an appropriate high quality 3-D data set which includes emission, meteorological, and chemical data. The data is used for the validation of mesoscale models and for chemical and meteorological process studies. The evolution of pho- tosmog episodes with high ozone concentrations depends on both chemical transfor- mation processes and meteorological conditions. As Marseille is situated between the Mediterranean Sea in the south and mountainous sites in the north, under weak large- scale flow the meteorological conditions are dominated by thermally driven circula- tion systems which strongly influence the horizontal transport of air pollutants. Ad- ditionally, vertically exchange processes like mountain venting and slope winds may contribute in the temporal evolution of the trace gas concentration of the city plume in the atmospheric boundary layer and are particularly studied by the Dornier flight measurements. Therefore the experiment was designed to measure both, the chemi- cal species and meteorological parameters with high resolution in space and time by surface stations, aircraft and vertical profiling systems like radiosondes, sodars and lidars. Results are shown (a) on the evolution of the wind field and the ozone concen- trations during June 25, when an ozone maximum develops about 60 km in the lee site of Marseille and (b) the vertical transport of air pollutants between the boundary layer and the free troposphere.

  15. Measurement of air entrainment in plasma jets

    International Nuclear Information System (INIS)

    Fincke, J.R.; Rodriquez, R.; Pentecost, C.G.

    1990-01-01

    The concentration and temperature of air entrained into argon and helium plasma jets has been measured using coherent anti-Stokes Raman spectroscopy (CARS). The argon plasma flow field is characterized by a short region of well behaved laminar flow near the nozzle exit followed by an abrupt transition to turbulence. Once the transition of turbulence occurs, air is rapidly mixed into the jet core. The location of the transition region is determined by the rapid cooling of the jet and the resulting increase in Reynolds number. In contrast, the helium plasma flow field never exceeds a Reynolds number of 200 and remains laminar. The entrainment process in this case is controlled by molecular diffusion rather than turbulent mixing. 9 refs., 5 figs., 1 tab

  16. Measurement of nitrogen dioxide in the air

    Energy Technology Data Exchange (ETDEWEB)

    Monteriolo, S C; Bertolaccini, M A

    1973-01-01

    A comparative study of automatic analytical methods for the monitoring of nitric oxide and nitrogen dioxide in the air indicates the need for a correct chemical conversion of the nonmeasurable species into the measurable species to obtain dependable results. The automatic colorimetric and chemiluminescent methods were compared to the manual colorimeter, and the electrochemical method was compared to chemiluminescence. Average, minimum, and maximum values are given for each comparison. All three methods are equally valid, in response linearity, sensitivity, and concentration limit, for the determination of nitric oxide, the measurable species. The determination of nitrogen dioxide, however, is strictly dependent on the efficiency of the conversion of the non-measurable species into the measurable form.

  17. 40 CFR 89.325 - Engine intake air temperature measurement.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature measurement. 89.325 Section 89.325 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Test Equipment Provisions § 89.325 Engine intake air temperature measurement. (a) Engine intake air...

  18. Graphene Visualizes the Ion Distribution on Air-Cleaved mica

    NARCIS (Netherlands)

    Bampoulis, Pantelis; Sotthewes, Kai; Siekman, Martin Herman; Zandvliet, Henricus J.W.; Poelsema, Bene

    2017-01-01

    The distribution of potassium (K+) ions on air-cleaved mica is important in many interfacial phenomena such as crystal growth, self-assembly and charge transfer on mica. However, due to experimental limitations to nondestructively probe single ions and ionic domains, their exact lateral organization

  19. Temperature distribution in graphite during annealing in air cooled reactors

    International Nuclear Information System (INIS)

    Oliveira Avila, C.R. de.

    1989-01-01

    A model for the evaluation temperature distributions in graphite during annealing operation in graphite. Moderated an-cooled reactors, is presented. One single channel and one dimension for air and graphite were considered. A numerical method based on finite control volumes was used for partioning the mathematical equations. The problem solution involves the use of unsteady equations of mass, momentum and energy conservation for air, and energy conservation for graphite. The source term was considered as stored energy release during annealing for describing energy conservation in the graphite. The coupling of energy conservation equations in air and graphite is performed by the heat transfer term betwen air and graphite. The results agree with experimental data. A sensitivity analysis shown that the termal conductivity of graphite and the maximum inlet channel temperature have great effect on the maximum temperature reached in graphite during the annealing. (author)

  20. Air Distribution in Rooms with a Fan-Driven Convector

    DEFF Research Database (Denmark)

    Larsen, Tine Steen; Bindels, Rob H.W.; Michalak, Lukasz

    2007-01-01

    the acceptable conditions for the supplyJlow rate and the temperature difference for the convector system. The paper shows that the air distribution from the convector results in comfortable velocity and temperature conditions with a heat load of 210 W. This is also confirmed by the draft ratings, which in all...... coming from the dijfuser is partly controlled by the momentum flow and partly from gravity forces, where the thermal load in the room and the temperature difference between room air and supply air affect the airflow from the convector. The convector system was tested in the same test room in which many......Experiments with a fan-driven convector used for both heating and cooling are de.scribed in this paper. Only the cooling situation is considered. The convector is positioned in the upper corner ofthe room, and from there the cold air is let out through the device along the ceiling. The airflow...

  1. 40 CFR 90.416 - Intake air flow measurement specifications.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Intake air flow measurement... Gaseous Exhaust Test Procedures § 90.416 Intake air flow measurement specifications. (a) If used, the engine intake air flow measurement method used must have a range large enough to accurately measure the...

  2. The Thermal Plume above a Standing Human Body Exposed to Different Air Distribution Strategies

    DEFF Research Database (Denmark)

    Liu, Li; Nielsen, Peter V.; Li, Yuguo

    2009-01-01

    This study compares the impact of air distribution on the thermal plume above a human body in indoor environment. Three sets of measurements are conducted in a full-scale test room with different ventilation conditions. One breathing thermal manikin standing in the room is used to simulate...... the human body. Long-time average air velocity profiles at locations closely above the manikin are taken to identify the wandering thermal plume....

  3. Bluetooth-based distributed measurement system

    International Nuclear Information System (INIS)

    Tang Baoping; Chen Zhuo; Wei Yuguo; Qin Xiaofeng

    2007-01-01

    A novel distributed wireless measurement system, which is consisted of a base station, wireless intelligent sensors and relay nodes etc, is established by combining of Bluetooth-based wireless transmission, virtual instrument, intelligent sensor, and network. The intelligent sensors mounted on the equipments to be measured acquire various parameters and the Bluetooth relay nodes get the acquired data modulated and sent to the base station, where data analysis and processing are done so that the operational condition of the equipment can be evaluated. The establishment of the distributed measurement system is discussed with a measurement flow chart for the distributed measurement system based on Bluetooth technology, and the advantages and disadvantages of the system are analyzed at the end of the paper and the measurement system has successfully been used in Daqing oilfield, China for measurement of parameters, such as temperature, flow rate and oil pressure at an electromotor-pump unit

  4. Bluetooth-based distributed measurement system

    Science.gov (United States)

    Tang, Baoping; Chen, Zhuo; Wei, Yuguo; Qin, Xiaofeng

    2007-07-01

    A novel distributed wireless measurement system, which is consisted of a base station, wireless intelligent sensors and relay nodes etc, is established by combining of Bluetooth-based wireless transmission, virtual instrument, intelligent sensor, and network. The intelligent sensors mounted on the equipments to be measured acquire various parameters and the Bluetooth relay nodes get the acquired data modulated and sent to the base station, where data analysis and processing are done so that the operational condition of the equipment can be evaluated. The establishment of the distributed measurement system is discussed with a measurement flow chart for the distributed measurement system based on Bluetooth technology, and the advantages and disadvantages of the system are analyzed at the end of the paper and the measurement system has successfully been used in Daqing oilfield, China for measurement of parameters, such as temperature, flow rate and oil pressure at an electromotor-pump unit.

  5. Bluetooth-based distributed measurement system

    Energy Technology Data Exchange (ETDEWEB)

    Tang Baoping; Chen Zhuo; Wei Yuguo; Qin Xiaofeng [Department of Mechatronics, College of Mechanical Engineering, Chongqing University, Chongqing, 400030 (China)

    2007-07-15

    A novel distributed wireless measurement system, which is consisted of a base station, wireless intelligent sensors and relay nodes etc, is established by combining of Bluetooth-based wireless transmission, virtual instrument, intelligent sensor, and network. The intelligent sensors mounted on the equipments to be measured acquire various parameters and the Bluetooth relay nodes get the acquired data modulated and sent to the base station, where data analysis and processing are done so that the operational condition of the equipment can be evaluated. The establishment of the distributed measurement system is discussed with a measurement flow chart for the distributed measurement system based on Bluetooth technology, and the advantages and disadvantages of the system are analyzed at the end of the paper and the measurement system has successfully been used in Daqing oilfield, China for measurement of parameters, such as temperature, flow rate and oil pressure at an electromotor-pump unit.

  6. Effect of supply air temperature on air distribution in a room with radiant heating and mechanical ventilation

    DEFF Research Database (Denmark)

    Wu, Xiaozhou; Zhao, Jianing; Fang, Lei

    2017-01-01

    and the horizontal distribution of containment concentration in the breathing zone were measured as the supply air temperature ranged from 15.0°C (59°F)to 19.0°C (66.2°F). The results showed that the vertical air temperature differences were less than 0.3°C (32.5°F) with FH+MV or CH+MV and between 1.9°C (35.4°F...

  7. 40 CFR 90.309 - Engine intake air temperature measurement.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Engine intake air temperature measurement. 90.309 Section 90.309 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR... Emission Test Equipment Provisions § 90.309 Engine intake air temperature measurement. (a) The measurement...

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

    Science.gov (United States)

    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) Humidity...

  9. Air distribution in office environment with asymmetric workstation layout using chilled beams

    Energy Technology Data Exchange (ETDEWEB)

    Koskela, Hannu; Haeggblom, Henna [Finnish Institute of Occupational Health, Lemminkaeisenkatu 14-18 B, 20520 Turku (Finland); Kosonen, Risto; Ruponen, Mika [Halton Oy, Niittyvillankuja 4, 01510 Vantaa (Finland)

    2010-09-15

    Air flow patterns and mean air speeds were studied under laboratory conditions representing a full scale open-plan office. Three basic conditions were tested: summer, spring/autumn and winter. Chilled beams were used to provide cooling, outdoor air supply and air distribution in the room. The heat sources had a notable influence on the flow pattern in the room causing large scale circulation and affecting the direction of inlet jets. The maximum air speed in the occupied zone was higher than the recommendations. The mean air speed was also high on at the floor level but low on at the head level. The air speed was highest in the summer case under high cooling load. Results indicate that especially with high heat loads, it is difficult to fulfill the targets of the existing standards in practice. Two main sources of draught risk were found: a) downfall of colliding inlet jets causing local maxima of air speed and b) large scale circulation caused by asymmetric layout of chilled beams and heat sources. The first phenomenon can cause local draught risk when the workstation is located in the downfall area. The flow pattern is not stable and the position of draught risk areas can change in time and also due to changes in room heat sources. The second phenomenon can cause more constant high air speeds on at the floor level. CFD-simulation was able to predict the general flow pattern but somewhat overestimated the air speed compared to measurements. (author)

  10. Monte Carlo simulation of air sampling methods for the measurement of radon decay products.

    Science.gov (United States)

    Sima, Octavian; Luca, Aurelian; Sahagia, Maria

    2017-08-01

    A stochastic model of the processes involved in the measurement of the activity of the 222 Rn decay products was developed. The distributions of the relevant factors, including air sampling and radionuclide collection, are propagated using Monte Carlo simulation to the final distribution of the measurement results. The uncertainties of the 222 Rn decay products concentrations in the air are realistically evaluated. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Systems Measures of Water Distribution System Resilience

    Energy Technology Data Exchange (ETDEWEB)

    Klise, Katherine A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Murray, Regan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Walker, La Tonya Nicole [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-01-01

    Resilience is a concept that is being used increasingly to refer to the capacity of infrastructure systems to be prepared for and able to respond effectively and rapidly to hazardous events. In Section 2 of this report, drinking water hazards, resilience literature, and available resilience tools are presented. Broader definitions, attributes and methods for measuring resilience are presented in Section 3. In Section 4, quantitative systems performance measures for water distribution systems are presented. Finally, in Section 5, the performance measures and their relevance to measuring the resilience of water systems to hazards is discussed along with needed improvements to water distribution system modeling tools.

  12. Quantifying air distribution, ventilation effectiveness and airborne pollutant transport in an aircraft cabin mockup

    Science.gov (United States)

    Wang, Aijun

    The health, safety and comfort of passengers during flight inspired this research into cabin air quality, which is closely related to its airflow distribution, ventilation effectiveness and airborne pollutant transport. The experimental facility is a full-scale aircraft cabin mockup. A volumetric particle tracking velocimetry (VPTV) technique was enhanced by incorporating a self-developed streak recognition algorithm. Two stable recirculation regions, the reverse flows above the seats and the main air jets from the air supply inlets formed the complicated airflow patterns inside the cabin mockup. The primary air flow was parallel to the passenger rows. The small velocity component in the direction of the cabin depth caused less net air exchange between the passenger rows than that parallel to the passenger rows. Different total air supply rate changed the developing behaviors of the main air jets, leading to different local air distribution patterns. Two indices, Local mean age of air and ventilation effectiveness factor (VEF), were measured at five levels of air supply rate and two levels of heating load. Local mean age of air decreased linearly with an increase in the air supply rate, while the VEF remained consistent when the air supply rate varied. The thermal buoyancy force from the thermal plume generated the upside plume flow, opposite to the main jet flow above the boundary seats and thus lowered the local net air exchange. The airborne transport dynamics depends on the distance between the source and the receptors, the relative location of pollutant source, and air supply rate. Exposure risk was significantly reduced with increased distance between source and receptors. Another possible way to decrease the exposure risk was to position the release source close to the exhaust outlets. Increasing the air supply rate could be an effective solution under some emergency situations. The large volume of data regarding the three-dimensional air velocities was

  13. X-ray Computed Tomography Assessment of Air Void Distribution in Concrete

    Science.gov (United States)

    Lu, Haizhu

    Air void size and spatial distribution have long been regarded as critical parameters in the frost resistance of concrete. In cement-based materials, entrained air void systems play an important role in performance as related to durability, permeability, and heat transfer. Many efforts have been made to measure air void parameters in a more efficient and reliable manner in the past several decades. Standardized measurement techniques based on optical microscopy and stereology on flat cut and polished surfaces are widely used in research as well as in quality assurance and quality control applications. Other more automated methods using image processing have also been utilized, but still starting from flat cut and polished surfaces. The emergence of X-ray computed tomography (CT) techniques provides the capability of capturing the inner microstructure of materials at the micrometer and nanometer scale. X-ray CT's less demanding sample preparation and capability to measure 3D distributions of air voids directly provide ample prospects for its wider use in air void characterization in cement-based materials. However, due to the huge number of air voids that can exist within a limited volume, errors can easily arise in the absence of a formalized data processing procedure. In this study, air void parameters in selected types of cement-based materials (lightweight concrete, structural concrete elements, pavements, and laboratory mortars) have been measured using micro X-ray CT. The focus of this study is to propose a unified procedure for processing the data and to provide solutions to deal with common problems that arise when measuring air void parameters: primarily the reliable segmentation of objects of interest, uncertainty estimation of measured parameters, and the comparison of competing segmentation parameters.

  14. Velocity distribution measurement in wire-spaced fuel pin bundle

    International Nuclear Information System (INIS)

    Mizuta, Hiroshi; Ohtake, Toshihide; Uruwashi, Shinichi; Takahashi, Keiichi

    1974-01-01

    Flow distribution measurement was made in the subchannels of a pin bundle in air flow. The present paper is interim because the target of this work is the decision of temperature of the pin surface in contact with wire spacers. The wire-spaced fuel pin bundle used for the experiment consists of 37 simulated fuel pins of stainless steel tubes, 3000 mm in length and 31.6 mm in diameter, which are wound spirally with 6 mm stainless steel wire. The bundle is wrapped with a hexagonal tube, 3500 mm in length and 293 mm in flat-to-flat distance. The bundle is fixed with knock-bar at the entrance of air flow in the hexagonal tube. The pitch of pins in the bundle is 37.6 mm (P/D=1.19) and the wrapping pitch of wire is 1100 mm (H/D=34.8). A pair of arrow-type 5-hole Pitot tubes are used to measure the flow velocity and the direction of air flow in the pin bundle. The measurement of flow distribution was made with the conditions of air flow rate of 0.33 m 3 /sec, air temperature of 45 0 C, and average Reynolds number of 15100 (average air velocity of 20.6 m/sec.). It was found that circular flow existed in the down stream of wire spacers, that axial flow velocity was slower in the subchannels, which contained wire spacers, than in those not affected by the wire, and that the flow angle to the axial velocity at the boundary of subchannels was two thirds smaller than wire wrapping angle. (Tai, I.)

  15. Air Distribution in a Room and Design Considerations of Mixing Ventilation by Flow Elements

    DEFF Research Database (Denmark)

    Nielsen, Peter V.; Jensen, Rasmus Lund; Pedersen, D. N.

    2001-01-01

    The paper shows detailed measurements of the air distribution in a room ventilated by mixing ventilation according to the specifications given by the International Energy Agency work. (Energy Conservation in Buildings and Community Systems Programme, Annex 20). It describes a number of flow...

  16. Spatial distribution of emissions to air – the SPREAD model

    DEFF Research Database (Denmark)

    Plejdrup, Marlene Schmidt; Gyldenkærne, Steen

    The National Environmental Research Institute (NERI), Aarhus University, completes the annual national emission inventories for greenhouse gases and air pollutants according to Denmark’s obligations under international conventions, e.g. the climate convention, UNFCCC and the convention on long...... quality modelling in exposure studies. SPREAD includes emission distributions for each sector in the Danish inventory system; stationary combustion, mobile sources, fugitive emissions from fuels, industrial processes, solvents and other product use, agriculture and waste. This model enables generation...

  17. System for measuring of air concentration in air-steam mixture during the transients

    International Nuclear Information System (INIS)

    Gorbenko, Gennady A.; Gakal, Pavlo G.; Epifanov, Konstantin S.; Osokin, Gennady V.; Smirnov, Sergey V.

    2006-01-01

    Description of system for air concentration measuring in air-steam mixture during the transients is represented. Air concentration measuring is based on discrete sampling method. The measuring system consists of sampler, transport pipeline, distributor and six measuring vessels. From the sampler air-steam mixture comes to distributor through transport pipeline and fills consecutively the measuring vessels. The true air concentration in place of measurement was defined based on measured air concentration in samples taken from measuring vessels. For this purpose, the mathematical model of transients in measuring system was developed. Air concentration transient in air-steam mixture in place of measurement was described in mathematical model by air concentration time-dependent function. The function parameters were defined based on air concentration measured in samples taken from measuring vessels. Estimated error of air concentration identification was about 10%. Measuring system was used in experiments on EREC BKV-213 test facility intended for testing of VVER-440/V-213 reactor barbotage-vacuum system

  18. Pirani pressure sensor with distributed temperature measurement

    NARCIS (Netherlands)

    de Jong, B.R.; Bula, W.P.; Zalewski, D.R.; van Baar, J.J.J.; Wiegerink, Remco J.

    2003-01-01

    Surface micro-machined distributed Pirani pressure gauges, with designed heater-to-heat sink distances (gap-heights) of 0.35 μm and 1.10 μm, are successfully fabricated, modeled and characterized. Measurements and model response correspond within 5% of the measured value in a pressure range of 10 to

  19. Air quality measurements in urban green areas - a case study

    Science.gov (United States)

    Kuttler, W.; Strassburger, A.

    The influence of traffic-induced pollutants (e.g. CO, NO, NO 2 and O 3) on the air quality of urban areas was investigated in the city of Essen, North Rhine-Westphalia (NRW), Germany. Twelve air hygiene profile measuring trips were made to analyse the trace gas distribution in the urban area with high spatial resolution and to compare the air hygiene situation of urban green areas with the overall situation of urban pollution. Seventeen measurements were made to determine the diurnal concentration courses within urban parks (summer conditions: 13 measurements, 530 30 min mean values, winter conditions: 4 measurements, 128 30 min mean values). The measurements were carried out during mainly calm wind and cloudless conditions between February 1995 and March 1996. It was possible to establish highly differentiated spatial concentration patterns within the urban area. These patterns were correlated with five general types of land use (motorway, main road, secondary road, residential area, green area) which were influenced to varying degrees by traffic emissions. Urban parks downwind from the main emission sources show the following typical temporal concentration courses: In summer rush-hour-dependent CO, NO and NO 2 maxima only occurred in the morning. A high NO 2/NO ratio was established during weather conditions with high global radiation intensities ( K>800 W m -2), which may result in a high O 3 formation potential. Some of the values measured found in one of the parks investigated (Gruga Park, Essen, area: 0.7 km 2), which were as high as 275 μg m -3 O 3 (30-min mean value) were significantly higher than the German air quality standard of 120 μg m -3 (30-min mean value, VDI Guideline 2310, 1996) which currently applies in Germany and about 20% above the maximum values measured on the same day by the network of the North Rhine-Westphalian State Environment Agency. In winter high CO and NO concentrations occur in the morning and during the afternoon rush-hour. The

  20. Development of measure methods of radon in indoor air

    International Nuclear Information System (INIS)

    Yaginuma, L.T.; Pela, C.A.; Navas, E.A.; Ghilardi, A.J.P.

    1992-01-01

    The development of some conventional measuring methods, aiming obtain an estimation of radon concentration in air, mainly in indoor air is described, including the charcoal absorption collector, Lucas cell and thermoluminescent dosemeters. (C.G.C)

  1. Distribution of air pollutants in the Inn Valley atmosphere during high concentration events in winter 2006

    International Nuclear Information System (INIS)

    Schnitzhofer, R.; Norman, M; Dunkl, J.; Wistaler, A.; Hansel, A.; Neininger, B.; Gohm, A.

    2006-01-01

    Full text: The goal of the INNOX field campaign, which took place during January and February 2006 near the town of Schwaz, was to obtain a three-dimensional picture of the spatial distribution of air pollutants in the Inn Valley during wintertime. For this purpose continuous ground based measurements and, on six chosen days, vertical profiles within the lowest 200 m above ground level (AGL) of the valley atmosphere of certain VOCs (benzene, toluene, etc.) and CO were performed using a proton-transfer-reaction mass spectrometry instrument (PTR-MS). For the soundings a 200-m long teflon line was fixed on a tethered balloon through which the air was sucked to the PTR-MS instrument and to a CO analyser. Next to the inlet on the tethered balloon meteorological data, such as air temperature, pressure, wind, were measured as well. Above the lowest 200 m AGL a research aircraft from MetAir AG (Switzerland), equipped with various instruments for in-situ measurements of air pollutants and meteorological data, was operated. A typical flight pattern consisted of five vertical cross sections between about 150 to 2500 m AGL and lasted about three hours. Altogether 25 hours of aircraft measurements were carried out on six different days. The combination of low-level balloon measurements and upper-level aircraft observations yields vertical profiles of various parameters which cover the whole valley atmosphere. Preliminary results which show strong vertical but also horizontal gradients of air pollutant concentrations will be presented. (author)

  2. Measuring heavy-tailedness of distributions

    Science.gov (United States)

    Jordanova, Pavlina K.; Petkova, Monika P.

    2017-12-01

    Different questions related with analysis of extreme values and outliers arise frequently in practice. To exclude extremal observations and outliers is not a good decision, because they contain important information about the observed distribution. The difficulties with their usage are usually related with the estimation of the tail index in case it exists. There are many measures for the center of the distribution, e.g. mean, mode, median. There are many measures for the variance, asymmetry and kurtosis, but there is no easy characteristic for heavy-tailedness of the observed distribution. Here we propose such a measure, give some examples and explore some of its properties. This allows us to introduce classification of the distributions, with respect to their heavy-tailedness. The idea is to help and navigate practitioners for accurate and easier work in the field of probability distributions. Using the properties of the defined characteristics some distribution sensitive extremal index estimators are proposed and their properties are partially investigated.

  3. Multi-objective optimization of cooling air distributions of grate cooler with different clinker particles diameters and air chambers by genetic algorithm

    International Nuclear Information System (INIS)

    Shao, Wei; Cui, Zheng; Cheng, Lin

    2017-01-01

    Highlights: • A multi-objective optimization model of air distributions of grate cooler by genetic algorithm is proposed. • Optimal air distributions of different conditions are obtained and validated by measurements. • The most economic average diameters of clinker particles is 0.02 m. • The most economic amount of air chambers is 9. - Abstract: The paper proposes a multi-objective optimization model of cooling air distributions of grate cooler in cement plant based on convective heat transfer principle and entropy generation minimization analysis. The heat transfer and flow models of clinker cooling process are brought out at first. Then the modified entropy generation numbers caused by heat transfer and viscous dissipation are considered as objective functions respectively which are optimized by genetic algorithm simultaneously. The design variables are superficial velocities of air chambers and thicknesses of clinker layer on different grate plates. The model is verified by a set of Pareto optimal solutions and scattered distributions of design variables. Sensitive analysis of average diameters of clinker particles and amount of air chambers are carried out based on the optimization model. The optimal cooling air distributions are compared by heat recovered, energy consumption of cooling fans and heat efficiency of grate cooler. And all of them are selected from the Pareto optimal solutions based on energy consumption of cooling fans minimization. The results show that the most effective and economic average diameter of clinker particles is 0.02 m and the amount of air chambers is 9.

  4. Air pollution assessment in the Slovak Republic in 2005. Measurement stations of air quality monitoring network

    International Nuclear Information System (INIS)

    Anon

    2006-05-01

    In this Appendix to the report 'Air pollution assessment in the Slovak Republic in 2005' the main characteristics of measurement stations of air quality monitoring network of the Slovak Republic are presented

  5. Air pollution assessment in the Slovak Republic in 2004. Measurement stations of air quality monitoring network

    International Nuclear Information System (INIS)

    Anon

    2005-07-01

    In this Appendix to the report 'Air pollution assessment in the Slovak Republic in 2004' the main characteristics of measurement stations of air quality monitoring network of the Slovak Republic are presented

  6. Multifunction Lidar for Air Data and Kinetic Air Hazard Measurement, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Ophir proposes to develop a multifunction, low-cost lidar capable of accurately measuring kinetic air hazards, and air data, simultaneously. The innovation is...

  7. Description of Supply Openings in Numerical Models for Room Air Distribution

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    This paper discusses various possibilities for describing supply openings in numerical models of room air distribution.......This paper discusses various possibilities for describing supply openings in numerical models of room air distribution....

  8. Energy analysis of under-floor air distribution (UFAD) system: An office building case study

    International Nuclear Information System (INIS)

    Alajmi, Ali F.; Abou-Ziyan, Hosny Z.; El-Amer, Wid

    2013-01-01

    Highlights: • The key issue for efficient performance of UFAD system is to ensure the thermal stratification establishment. • The unnecessarily excess air supplied to the room deteriorates the thermal stratification. • Improper UFAD operation increases the fan power and HVAC electric demand. • The proper UFAD system is typically more efficient than the existed UFAD system with energy savings of about 23–37%. • UFAD system shows over the CBAD system saving by about 37–39% during the peak months and 51% during October. - Abstract: This paper presents the results of an experimental and theoretical investigation to evaluate an under-floor air distribution (UFAD) system existed in an office building working on hot climate. Air temperature a distribution and supply air velocity are measured in two measuring stations; each consists of eight temperature sensors which were installed to measure room air temperatures along zone height. The obtained data shows an inefficient operation of the UFAD system which deteriorates the advantages of energy saving that presumed by UFAD system. The building energy simulation program, EnergyPlus, was used to identify the best setting of UFAD system and compare it with the existed UFAD and the conventional ceiling based air distribution (CBAD) system. The simulation results show that setting of room thermostat at 26 °C and supply air temperature at 18 °C provides the best efficient UFAD system. Due to improper operation of the tested UFAD system, its actual consumption is found to be higher than the best simulated UFAD by 23–37% during July to October. Also, the simulation results show that the HVAC demand of UFAD is lower than CBAD by 37–39% during July–September and 51% in October

  9. Next-generation air measurement technologies | Science ...

    Science.gov (United States)

    This is a presentation at a workshop in Chicago on emerging air monitoring technologies, hosted by a local nonprofit. The audience is composed of a mixture of technical backgrounds. This presentation will be part of an opening panel and the goal is to give an overview of the state of science on emerging air sensor technology. This is a presentation at a workshop in Chicago on emerging air monitoring technologies, hosted by a local nonprofit. The audience is composed of a mixture of technical backgrounds. This presentation will be part of an opening panel and the goal is to give an overview of the state of science on emerging air sensor technology.

  10. Drop size distribution evolution after continuous or intermittent injection of butane or propane in a confined air flow

    NARCIS (Netherlands)

    Knubben, G.; Geld, van der C.W.M.

    1999-01-01

    Drop size distributions and velocities have been measured of n-butane and propane sprays, rapidly evaporating in air flowing at constant velocity, 15 m/s typically. The inlet air temperature has been found to be of main importance in the evaporation process. After a period of the order of the

  11. Air temperature measurements based on the speed of sound to compensate long distance interferometric measurements

    Directory of Open Access Journals (Sweden)

    Astrua Milena

    2014-01-01

    Full Text Available A method to measure the real time temperature distribution along an interferometer path based on the propagation of acoustic waves is presented. It exploits the high sensitivity of the speed of sound in air to the air temperature. In particular, it takes advantage of a special set-up where the generation of the acoustic waves is synchronous with the amplitude modulation of a laser source. A photodetector converts the laser light to an electronic signal considered as reference, while the incoming acoustic waves are focused on a microphone and generate a second signal. In this condition, the phase difference between the two signals substantially depends on the temperature of the air volume interposed between the sources and the receivers. The comparison with the traditional temperature sensors highlighted the limit of the latter in case of fast temperature variations and the advantage of a measurement integrated along the optical path instead of a sampling measurement. The capability of the acoustic method to compensate the interferometric distance measurements due to air temperature variations has been demonstrated for distances up to 27 m.

  12. measurements of distribution coefficients and lipophilicity values

    African Journals Online (AJOL)

    Preferred Customer

    octanol and water, followed by measuring the distribution of the solute in ... Instrumentation and apparatus: HPLC-UV-DAD and HPLC–ESI-MS experiments .... process in the determination of KD and log P values for the HFSLM extracts. ..... Perrin, D.D.; Dempsey, B. Buffers for pH and Metal Ion Control, Chapman and Hall:.

  13. Measurements and prediction of inhaled air quality with personalized ventilation

    DEFF Research Database (Denmark)

    Cermak, Radim; Majer, M.; Melikov, Arsen Krikor

    2002-01-01

    the room air) at flow rates ranging from less than 5 L/s up to 23 L/s. The air quality assessment was based on temperature measurements of the inhaled air and on the portion of the personalized air inhaled. The percentage of dissatisfied with the air quality was predicted. The results suggest......This paper examines the performance of five different air terminal devices for personalized ventilation in relation to the quality of air inhaled by a breathing thermal manikin in a climate chamber. The personalized air was supplied either isothermally or non-isothermally (6 deg.C cooler than...... that regardless of the temperature combinations, personalized ventilation may decrease significantly the number of occupants dissatisfied with the air quality. Under non-isothermal conditions the percentage of dissatisfied may decrease up to 4 times....

  14. THE MEASUREMENT AND DISTRIBUTION OF WOOD DUST

    Directory of Open Access Journals (Sweden)

    Andrea Rosario Proto

    2010-03-01

    Full Text Available In Italy, the woodworking industry presents many issues in terms of occupational health and safety. This study on exposure to wood dust could contribute to the realization of a prevention model in order to limit exposure to carcinogenic agents to the worker. The sampling methodology illustrated the analysis of dust emissions from the woodworking machinery in operation throughout the various processing cycles. The quantitative and qualitative assessment of exposure was performed using two different methodologies. The levels of wood dust were determined according to EN indications and sampling was conducted using IOM and Cyclon personal samplers. The qualitative research of wood dust was performed using an advanced laser air particle counter. This allowed the number of particles present to be counted in real time. The results obtained allowed for an accurate assessment of the quality of the dust emitted inside the workplace during the various processing phases. The study highlighted the distribution of air particles within the different size classes, the exact number of both thin and ultra-thin dusts, and confirmed the high concentration of thin dust particles which can be very harmful to humans.

  15. The MUMBA campaign: measurements of urban, marine and biogenic air

    Science.gov (United States)

    Paton-Walsh, Clare; Guérette, Élise-Andrée; Kubistin, Dagmar; Humphries, Ruhi; Wilson, Stephen R.; Dominick, Doreena; Galbally, Ian; Buchholz, Rebecca; Bhujel, Mahendra; Chambers, Scott; Cheng, Min; Cope, Martin; Davy, Perry; Emmerson, Kathryn; Griffith, David W. T.; Griffiths, Alan; Keywood, Melita; Lawson, Sarah; Molloy, Suzie; Rea, Géraldine; Selleck, Paul; Shi, Xue; Simmons, Jack; Velazco, Voltaire

    2017-06-01

    The Measurements of Urban, Marine and Biogenic Air (MUMBA) campaign took place in Wollongong, New South Wales (a small coastal city approximately 80 km south of Sydney, Australia) from 21 December 2012 to 15 February 2013. Like many Australian cities, Wollongong is surrounded by dense eucalyptus forest, so the urban airshed is heavily influenced by biogenic emissions. Instruments were deployed during MUMBA to measure the gaseous and aerosol composition of the atmosphere with the aim of providing a detailed characterisation of the complex environment of the ocean-forest-urban interface that could be used to test the skill of atmospheric models. The gases measured included ozone, oxides of nitrogen, carbon monoxide, carbon dioxide, methane and many of the most abundant volatile organic compounds. The aerosol characterisation included total particle counts above 3 nm, total cloud condensation nuclei counts, mass concentration, number concentration size distribution, aerosol chemical analyses and elemental analysis.The campaign captured varied meteorological conditions, including two extreme heat events, providing a potentially valuable test for models of future air quality in a warmer climate. There was also an episode when the site sampled clean marine air for many hours, providing a useful additional measure of the background concentrations of these trace gases within this poorly sampled region of the globe. In this paper we describe the campaign, the meteorology and the resulting observations of atmospheric composition in general terms in order to equip the reader with a sufficient understanding of the Wollongong regional influences to use the MUMBA datasets as a case study for testing a chemical transport model. The data are available from PANGAEA (pangaea.de/10.1594/PANGAEA.871982" target="_blank">http://doi.pangaea.de/10.1594/PANGAEA.871982).

  16. Measurement Error Correction for Predicted Spatiotemporal Air Pollution Exposures.

    Science.gov (United States)

    Keller, Joshua P; Chang, Howard H; Strickland, Matthew J; Szpiro, Adam A

    2017-05-01

    Air pollution cohort studies are frequently analyzed in two stages, first modeling exposure then using predicted exposures to estimate health effects in a second regression model. The difference between predicted and unobserved true exposures introduces a form of measurement error in the second stage health model. Recent methods for spatial data correct for measurement error with a bootstrap and by requiring the study design ensure spatial compatibility, that is, monitor and subject locations are drawn from the same spatial distribution. These methods have not previously been applied to spatiotemporal exposure data. We analyzed the association between fine particulate matter (PM2.5) and birth weight in the US state of Georgia using records with estimated date of conception during 2002-2005 (n = 403,881). We predicted trimester-specific PM2.5 exposure using a complex spatiotemporal exposure model. To improve spatial compatibility, we restricted to mothers residing in counties with a PM2.5 monitor (n = 180,440). We accounted for additional measurement error via a nonparametric bootstrap. Third trimester PM2.5 exposure was associated with lower birth weight in the uncorrected (-2.4 g per 1 μg/m difference in exposure; 95% confidence interval [CI]: -3.9, -0.8) and bootstrap-corrected (-2.5 g, 95% CI: -4.2, -0.8) analyses. Results for the unrestricted analysis were attenuated (-0.66 g, 95% CI: -1.7, 0.35). This study presents a novel application of measurement error correction for spatiotemporal air pollution exposures. Our results demonstrate the importance of spatial compatibility between monitor and subject locations and provide evidence of the association between air pollution exposure and birth weight.

  17. Multichannel system for angular distribution measurements

    International Nuclear Information System (INIS)

    Burjan, V.; Kroha, V.; Putz, K.

    A description is given of the individual blocks of the spectrometric apparatus used for measuring the angular distribution of particle spectra and excitation functions of (d,p) reactions at an electrostatic accelerator and the U-120 M cyclotron, both operating at the Nuclear Physics Institute of the Czechoslovak Academy of Sciences at Rez. Main attention was devoted to attaining maximum energy resolution at a high measurement efficiency, this by installing 8 independent spectrometric chains allowing simultaneous measurement of angular distribution in 8 points of the beam. The semiconductor detectors were cooled to -40 degC to -60 degC, which significantly reduced the level of inherent detector noise. An energy resolution of 13 keV was attained using Tesla detectors at a particle energy of 11 MeV. A brief review of data processing and software is given. (B.S.)

  18. Measurement Methods to Determine Air Leakage Between Adjacent Zones

    Energy Technology Data Exchange (ETDEWEB)

    Hult, Erin L. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dickerhoff, Darryl J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Price, Phillip N. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-09-01

    Air leakage between adjacent zones of a building can lead to indoor air quality and energy efficiency concerns, however there is no existing standard for measuring inter-zonal leakage. In this study, synthesized data and field measurements are analyzed in order to explore the uncertainty associated with different methods for collecting and analyzing fan pressurization measurements to calculate interzone leakage.

  19. Statistical modeling of urban air temperature distributions under different synoptic conditions

    Science.gov (United States)

    Beck, Christoph; Breitner, Susanne; Cyrys, Josef; Hald, Cornelius; Hartz, Uwe; Jacobeit, Jucundus; Richter, Katja; Schneider, Alexandra; Wolf, Kathrin

    2015-04-01

    Within urban areas air temperature may vary distinctly between different locations. These intra-urban air temperature variations partly reach magnitudes that are relevant with respect to human thermal comfort. Therefore and furthermore taking into account potential interrelations with other health related environmental factors (e.g. air quality) it is important to estimate spatial patterns of intra-urban air temperature distributions that may be incorporated into urban planning processes. In this contribution we present an approach to estimate spatial temperature distributions in the urban area of Augsburg (Germany) by means of statistical modeling. At 36 locations in the urban area of Augsburg air temperatures are measured with high temporal resolution (4 min.) since December 2012. These 36 locations represent different typical urban land use characteristics in terms of varying percentage coverages of different land cover categories (e.g. impervious, built-up, vegetated). Percentage coverages of these land cover categories have been extracted from different sources (Open Street Map, European Urban Atlas, Urban Morphological Zones) for regular grids of varying size (50, 100, 200 meter horizonal resolution) for the urban area of Augsburg. It is well known from numerous studies that land use characteristics have a distinct influence on air temperature and as well other climatic variables at a certain location. Therefore air temperatures at the 36 locations are modeled utilizing land use characteristics (percentage coverages of land cover categories) as predictor variables in Stepwise Multiple Regression models and in Random Forest based model approaches. After model evaluation via cross-validation appropriate statistical models are applied to gridded land use data to derive spatial urban air temperature distributions. Varying models are tested and applied for different seasons and times of the day and also for different synoptic conditions (e.g. clear and calm

  20. Use of electrochemical sensors for measurement of air pollution: correcting interference response and validating measurements

    Science.gov (United States)

    Cross, Eben S.; Williams, Leah R.; Lewis, David K.; Magoon, Gregory R.; Onasch, Timothy B.; Kaminsky, Michael L.; Worsnop, Douglas R.; Jayne, John T.

    2017-09-01

    The environments in which we live, work, and play are subject to enormous variability in air pollutant concentrations. To adequately characterize air quality (AQ), measurements must be fast (real time), scalable, and reliable (with known accuracy, precision, and stability over time). Lower-cost air-quality-sensor technologies offer new opportunities for fast and distributed measurements, but a persistent characterization gap remains when it comes to evaluating sensor performance under realistic environmental sampling conditions. This limits our ability to inform the public about pollution sources and inspire policy makers to address environmental justice issues related to air quality. In this paper, initial results obtained with a recently developed lower-cost air-quality-sensor system are reported. In this project, data were acquired with the ARISense integrated sensor package over a 4.5-month time interval during which the sensor system was co-located with a state-operated (Massachusetts, USA) air quality monitoring station equipped with reference instrumentation measuring the same pollutant species. This paper focuses on validating electrochemical (EC) sensor measurements of CO, NO, NO2, and O3 at an urban neighborhood site with pollutant concentration ranges (parts per billion by volume, ppb; 5 min averages, ±1σ): [CO] = 231 ± 116 ppb (spanning 84-1706 ppb), [NO] = 6.1 ± 11.5 ppb (spanning 0-209 ppb), [NO2] = 11.7 ± 8.3 ppb (spanning 0-71 ppb), and [O3] = 23.2 ± 12.5 ppb (spanning 0-99 ppb). Through the use of high-dimensional model representation (HDMR), we show that interference effects derived from the variable ambient gas concentration mix and changing environmental conditions over three seasons (sensor flow-cell temperature = 23.4 ± 8.5 °C, spanning 4.1 to 45.2 °C; and relative humidity = 50.1 ± 15.3 %, spanning 9.8-79.9 %) can be effectively modeled for the Alphasense CO-B4, NO-B4, NO2-B43F, and Ox-B421 sensors, yielding (5 min average) root

  1. Experiments of Accuracy Air Ion Field Measurement

    Czech Academy of Sciences Publication Activity Database

    Bartušek, Karel; Fiala, P.; Jirků, T.; Kadlecová, E.

    2007-01-01

    Roč. 3, č. 8 (2007), s. 1330-1333 ISSN 1931-7360 Institutional research plan: CEZ:AV0Z20650511 Keywords : air ion field * gerdien condenser * picoampermeter Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  2. Mobile source air toxics mitigation measures.

    Science.gov (United States)

    2013-10-01

    In accordance with the Federal Highway Administration (FHWA) Interim Guidance Update on Mobile Source Air Toxic Analysis in NEPA Documents (September 30, 2009), transportation projects subject to the National Environmental Policy Act (NEPA) mus...

  3. Distribution and Room Air Mixing Risks to Retrofitted Homes

    Energy Technology Data Exchange (ETDEWEB)

    Burdick, A. [IBACOS, Inc., Pittsburgh, PA (United States)

    2014-12-01

    An energy efficiency upgrade reduces a home’s heating and cooling load. If the load reduction is great enough and the heating, ventilation, and air conditioning system warrants replacement, that system is often upgraded with a more efficient, lower capacity system that meets the load of the upgraded house. For a single-story house with floor supply air diffusers, the ducts often are removed and upgraded. For houses with ducts that are embedded in walls, the cost of demolition precludes the replacement of ducts. The challenge with the use of existing ducts is that the reduced airflow creates a decreased throw at the supply registers, and the supply air and room air do not mix well, leading to potential thermal comfort complaints. This project investigates this retrofit scenario. The issues and solutions discussed here are relevant to all climate zones, with emphasis on climates that require cooling. In this project, IBACOS performed load calculations for a two-story 1960s house and characterized duct sizes and layouts based on industry “rules of thumb” (Herk et al. 2014). The team performed duct-sizing calculations for unaltered ducts and post-retrofit airflows and examined airflow velocities and pressure changes with respect to various factors. The team then used a mocked-up duct and register setup to measure the characteristics of isothermal air—to reduce the effects of buoyancy from the observations—passing through the duct and leaving the register.

  4. Hazardous air pollutant handbook: measurements, properties, and fate in ambient air

    Energy Technology Data Exchange (ETDEWEB)

    Spicer, C.W. (ed.); Gordon, S.M.; Kelly, T.J.; Holdren, M.W.; Mukund, R. [Battelle, Columbus, OH (United States)

    2002-07-01

    Focussing on the 188 hazardous air pollutants (HAPs) identified in the Title III of the US Clean Air Act Amendments, this work reviews the methods used to identify, measure, and locate the presence of toxics in ambient air. After a classification and characterization of the HAPs, the current status of ambient measurement methods are surveyed and categorized according to applicable, likely, and potential methods. The results of studies of ambient air concentrations of the HAPs are presented. Methods used to study atmospheric transformations of toxic air pollutants are reviewed and the concept of atmospheric lifetimes of HAPs is discussed.

  5. A Fleet of Low-Cost Sensor Based Air Quality Monitors Is Used to Measure Carbon Dioxide and Carbon Monoxide in Two Settings: In the Ambient Environment to Explore the Regional-Scale Spatial Variability of These Compounds Via a Distributed Network, and in Homes to Investigate How Heating during Winter Months can Impact Indoor Air Quality.

    Science.gov (United States)

    Casey, J. G.; Hannigan, M.; Collier, A. M.; Coffey, E.; Piedrahita, R.

    2016-12-01

    Affordable, small, portable, quiet tools to measure atmospheric trace gases and air quality enable novel experimental design and new findings. Members of the Hannigan Lab at the University of Colorado in Boulder have been working over the last few years to integrate emerging affordable gas sensors into such an air quality monitor. Presented here are carbon monoxide (CO) and carbon dioxide (CO2) measurements from two field experiments that utilized these tools. In the first experiment, ten air quality monitors were located northeast of Boulder throughout the Denver Julesburg oil and gas basin. The Colorado Department of Health and Environment has several air quality monitoring sites in this broader region, each in an Urban center. One goal of the experiment was to determine whether or not significant spatial variability of EPA criteria pollutants like CO, exists on a sub-regulatory monitoring grid scale. Another goal of the experiment was to compare rural sampling locations with urban sites. The monitors collected continuous data (sampling every 15 seconds) at each location over the course of several months. Our sensor calibration procedures are presented along with our observations and an analysis of the spatial and temporal variability in CO and CO2. In the second experiment, we used eight of our air quality monitors to better understand how home heating fuel type can impact indoor air quality in two communities on the Navajo Nation. We sought to compare air quality in homes using one of four different fuels for heat (wood, wood plus coal, pellet, and gas). There are many factors that contribute to indoor air quality and the impact of an emission source, like a woodstove, within a home. Having multiple, easily deployable, air quality monitors allowed us to account for many of these factors. We sampled four homes at a time, aiming for one home from each of our fuel groups in each sampling period. We sampled inside and outside of each home for a period of 3-4 days

  6. Microscale air quality impacts of distributed power generation facilities.

    Science.gov (United States)

    Olaguer, Eduardo P; Knipping, Eladio; Shaw, Stephanie; Ravindran, Satish

    2016-08-01

    The electric system is experiencing rapid growth in the adoption of a mix of distributed renewable and fossil fuel sources, along with increasing amounts of off-grid generation. New operational regimes may have unforeseen consequences for air quality. A three-dimensional microscale chemical transport model (CTM) driven by an urban wind model was used to assess gaseous air pollutant and particulate matter (PM) impacts within ~10 km of fossil-fueled distributed power generation (DG) facilities during the early afternoon of a typical summer day in Houston, TX. Three types of DG scenarios were considered in the presence of motor vehicle emissions and a realistic urban canopy: (1) a 25-MW natural gas turbine operating at steady state in either simple cycle or combined heating and power (CHP) mode; (2) a 25-MW simple cycle gas turbine undergoing a cold startup with either moderate or enhanced formaldehyde emissions; and (3) a data center generating 10 MW of emergency power with either diesel or natural gas-fired backup generators (BUGs) without pollution controls. Simulations of criteria pollutants (NO2, CO, O3, PM) and the toxic pollutant, formaldehyde (HCHO), were conducted assuming a 2-hr operational time period. In all cases, NOx titration dominated ozone production near the source. The turbine scenarios did not result in ambient concentration enhancements significantly exceeding 1 ppbv for gaseous pollutants or over 1 µg/m(3) for PM after 2 hr of emission, assuming realistic plume rise. In the case of the datacenter with diesel BUGs, ambient NO2 concentrations were enhanced by 10-50 ppbv within 2 km downwind of the source, while maximum PM impacts in the immediate vicinity of the datacenter were less than 5 µg/m(3). Plausible scenarios of distributed fossil generation consistent with the electricity grid's transformation to a more flexible and modernized system suggest that a substantial amount of deployment would be required to significantly affect air quality on

  7. Measurement and Modelling of Air Flow Rate in a Naturally Ventilated Double Skin Facade

    DEFF Research Database (Denmark)

    Heiselberg, Per; Kalyanova, Olena; Jensen, Rasmus Lund

    2008-01-01

    Air flow rate in a naturally ventilated double skin façade (DSF) is extremely difficult to measure due to the stochastic nature of wind, and as a consequence non-uniform and dynamic flow conditions. This paper describes the results of two different methods to measure the air flow in a full...... by the thermal simulation program, BSim, based on measured weather boundary conditions are compared to the measured air temperature, temperature gradient and mass flow rate in the DSF cavity. The results show that it is possible to predict the temperature distribution and airflow in the DSF although some......-scale outdoor test facility with a naturally ventilated double skin façade. Although both methods are difficult to use under such dynamic air flow conditions, they show reasonable agreement and can be used for experimental validation of numerical models of natural ventilation air flow in DSF. Simulations...

  8. Measurement of Indoor Air Quality by Means of a Breathing Thermal Manikin

    DEFF Research Database (Denmark)

    Brohus, Henrik

    When a person is located in a contaminant field with significant gradients the contaminant distribution is modified locally due to the entrainment and transport of room air in the human convective boundary layer as well as due to the effect of the person acting as an obstacle to the flow field, etc....... The local modification of the concentration distribution may affect the personal exposure significantly and, thus, the indoor air quality actually experienced. In this paper measurements of indoor air quality by means of a Breathing Thermal Manikin (BTM) are presented....

  9. Distribution of Exhaled Contaminants and Personal Exposure in a Room using Three Different Air Distribution Strategies

    DEFF Research Database (Denmark)

    Olmedo, Inés; Nielsen, Peter V.; Adana, M. Ruiz de

    2012-01-01

    The level of exposure to human exhaled contaminants in a room depends not only on the air distribution system but also on people’s different positions, the distance between them, people’s activity level and height, direction of exhalation, and the surrounding temperature and temperature gradient...... between the manikins are changed to study the influence on the level of exposure. The results show that the air exhaled by a manikin flows a longer distance with a higher concentration in case of displacement ventilation than in the other two cases, indicating a significant exposure to the contaminants....... Human exhalation is studied in detail for different distribution systems: displacement and mixing ventilation as well as a system without mechanical ventilation. Two thermal manikins breathing through the mouth are used to simulate the exposure to human exhaled contaminants. The position and distance...

  10. Ion Distribution Measurement In Plasma Focus

    International Nuclear Information System (INIS)

    Suryadi; Sunardi; Usada, Widdi; Purwadi, Agus; Zaenuri, Akhmad

    1996-01-01

    Measurement of the Argon ion distribution in plasma focus by using Faraday cup has been done. The intensity of ion beam followed the I Rn rule, n=1,02. In the operation condition of 0,8 mbar and 12,5 kV the current sheath spen 2.2 to 2.4 μsecond in the rundown phase. Cu ion was also been observed in the Faraday cup

  11. Correlation of Air Quality Data to Ultrafine Particles (UFP Concentration and Size Distribution in Ambient Air

    Directory of Open Access Journals (Sweden)

    Werner Hofmann

    2010-07-01

    Full Text Available This study monitored ultrafine particles (UFP concurrent with environmental air quality data, investigating whether already existing instrumentation used by environmental authorities can provide reference values for estimating UFP concentrations. Of particular interest was the relation of UFP to PM10 (particulate matter and nitrogen oxides (NOx, NO2 in ambient air. Existing PM measurement methods alone did not correspond exactly enough with the actual particle number, but we observed a link between NOx and NO2 to UFP concentration. The combined data could act as proxy-indicator for authorities in estimating particle number concentrations, but cannot replace UFP monitoring.

  12. Concentration of Radon Progeny in Air by Alpha Spectrometry Measurement

    International Nuclear Information System (INIS)

    Acena, M. L.; Crespo, M. T.

    1989-01-01

    The concentration of radon progeny in air has been determined by alpha spectrometry measurement of 214 Po and 318 Po. A known volume of air was passed through a filter, then the alpha activity was directly measured on this filter. (Author) 15 refs

  13. Lower cost air measurement technology – what is on the ...

    Science.gov (United States)

    This presentation is to the MARAMA 2014 annual monitoring meeting and is an invited talk to provide an overview on lower cost air measurement technology. This presentation is to the MARAMA 2014 annual monitoring meeting and is an invited talk to provide an overview on lower cost air measurement technology.

  14. Measurement of radon daughters in air samples by alpha spectroscopy

    International Nuclear Information System (INIS)

    Acena, M.L.; Crespo, M.T.

    1989-01-01

    The concentration of radon progeny in air has been determined by alpha spectrometry measurement of polonium 214 and polonium 218. A known volume of air was passed through a filter, then the alpha activity was directly measured on this filter (Author)

  15. Test Protocol for Room-to-Room Distribution of Outside Air by Residential Ventilation Systems

    Energy Technology Data Exchange (ETDEWEB)

    Barley, C. D.; Anderson, R.; Hendron, B.; Hancock, E.

    2007-12-01

    This test and analysis protocol has been developed as a practical approach for measuring outside air distribution in homes. It has been used successfully in field tests and has led to significant insights on ventilation design issues. Performance advantages of more sophisticated ventilation systems over simpler, less-costly designs have been verified, and specific problems, such as airflow short-circuiting, have been identified.

  16. Statistical Analysis of Spatiotemporal Heterogeneity of the Distribution of Air Quality and Dominant Air Pollutants and the Effect Factors in Qingdao Urban Zones

    Directory of Open Access Journals (Sweden)

    Xiangwei Zhao

    2018-04-01

    Full Text Available Air pollution has impacted people’s lives in urban China, and the analysis of the distribution and driving factors behind air quality has become a current research focus. In this study, the temporal heterogeneity of air quality (AQ and the dominant air pollutants across the four seasons were analyzed based on the Kruskal-Wallis rank-sum test method. Then, the spatial heterogeneity of AQ and the dominant air pollutants across four sites were analyzed based on the Wilcoxon signed-rank test method. Finally, the copula model was introduced to analyze the effect of relative factors on dominant air pollutants. The results show that AQ and dominant air pollutants present significant spatiotemporal heterogeneity in the study area. AQ is worst in winter and best in summer. PM10, O3, and PM2.5 are the dominant air pollutants in spring, summer, and winter, respectively. The average concentration of dominant air pollutants presents significant and diverse daily peaks and troughs across the four sites. The main driving factors are pollutants such as SO2, NO2, and CO, so pollutant emission reduction is the key to improving air quality. Corresponding pollution control measures should account for this heterogeneity in terms of AQ and the dominant air pollutants among different urban zones.

  17. Device for measuring mass of air. Einrichtung zur Luftmassenmessung

    Energy Technology Data Exchange (ETDEWEB)

    Sass, W

    1989-09-28

    In a device for measuring the mass of air, particularly for vehicles with internal combustion engines, with a measurement bridge, in one branch of which an air flow resistance, particularly a hot film sensor, which has air flowing round it, is connected in series with a measuring resistance and in another branch of which a compensation resistance measuring the air temperature is connected in series with a fixed resistor, where the bridge differential voltage is measured in the zero branch of the measuring bridge and the resulting signal is used to control a transistor valve situated in the bridge supply path of a bridge supply source with an emitter connected to the bridge via the transistor base for bridge compensation and where the voltage at the measurement resistance after bridge compensation is evaluated as a measure of the air flow, the invention proposes that the transistor valve should be made as an npn transistor blocking for negative voltage peaks in the bridge supply path. This ensures that for netgative voltage peaks in the supply line, the transistor valve closes temporarily and overheating of the measurement bridge is prevented. Such overheating would lead to measurement of too great air mass flow and therefore to a dangerously too rich fuel/air mixture, for example (instead the negative voltage peaks give a safe temporary lean mixture).

  18. A gridded air counter for measuring exoelectrons

    International Nuclear Information System (INIS)

    Nagase, Makoto; Chiba, Yoshiya; Kirihata, Humiaki.

    1980-01-01

    A gridded air counter with a quenching circuit is described, which serves to detect low-energy electrons such as thermionic electrons, photoelectrons and exoelectrons emitted into the atmospheric air. The air counter consists of a loop-shaped anode and two grids provided for quenching the gas discharge and for protecting the electron emitter from the positive ion bombardment. The quenching circuit with a high input sensitivity of 5 mV detects the initiation gas discharge caused by an incident electron and immediately supplies a rectangular wave pulse of 300 V in amplitude and of more than 3 msec in width to the quenching grid near the anode. Simultaneously, the voltage of the suppressor grid is brought down and kept at -30 V against the earthed sample for the same period of time. Performance of the gridded air counter was examined by use of photoelectrons emitted from an abraded aluminum plate. The quenching action was successfully accomplished in the anode voltage range from 3.65 to 3.95 kV. The photoelectrons emitted into the atmosphere could be counted stably by use of this counter. (author)

  19. Chapter 22: Compressed Air Evaluation Protocol. The Uniform Methods Project: Methods for Determining Energy Efficiency Savings for Specific Measures

    Energy Technology Data Exchange (ETDEWEB)

    Kurnik, Charles W [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Benton, Nathanael [Nexant, Inc., San Francisco, CA (United States); Burns, Patrick [Nexant, Inc., San Francisco, CA (United States)

    2017-10-18

    Compressed-air systems are used widely throughout industry for many operations, including pneumatic tools, packaging and automation equipment, conveyors, and other industrial process operations. Compressed-air systems are defined as a group of subsystems composed of air compressors, air treatment equipment, controls, piping, pneumatic tools, pneumatically powered machinery, and process applications using compressed air. A compressed-air system has three primary functional subsystems: supply, distribution, and demand. Air compressors are the primary energy consumers in a compressed-air system and are the primary focus of this protocol. The two compressed-air energy efficiency measures specifically addressed in this protocol are: High-efficiency/variable speed drive (VSD) compressor replacing modulating, load/unload, or constant-speed compressor; and Compressed-air leak survey and repairs. This protocol provides direction on how to reliably verify savings from these two measures using a consistent approach for each.

  20. Measuring hydrogen-isotope distribution profiles

    International Nuclear Information System (INIS)

    Poppe, C.H.

    1977-01-01

    A new nondestructive technique was developed for measuring the depth distribution of hydrogen isotopes absorbed or implanted near the surface of any material. The method allows real-time study of the inventory and diffusion of hydrogen, deuterium, and tritium. Briefly, the technique involves bombarding the surface with a monoenergetic beam of ions chosen for their ability to react with the hydrogen isotope in question and produce fast neutrons. The energy distribution of the neutrons is a sensitive indicator of the energy of the bombarding particles at the instant of reaction, and hence of the depth of the reaction sites below he surface of the material. A sensitivity of one part per million was obtained for tritium in copper. The technique is applicable to several energy-related materials problems. 5 figures

  1. Depth Distribution Of The Maxima Of Extensive Air Shower

    Science.gov (United States)

    Adams, J. H.; Howell, L. W.

    2003-01-01

    Observations of the extensive air showers from space can be free from interference by low altitude clouds and aerosols if the showers develop at a sufficiently high altitude. In this paper we explore the altitude distribution of shower maxima to determine the fraction of all showers that will reach their maxima at sufficient altitudes to avoid interference from these lower atmosphere phenomena. Typically the aerosols are confined within a planetary boundary layer that extends from only 2-3 km above the Earth's surface. Cloud top altitudes extend above 15 km but most are below 4 km. The results reported here show that more than 75% of the showers that will be observed by EUSO have maxima above the planetary boundary layer. The results also show that more than 50% of the showers that occur on cloudy days have their maxima above the cloud tops.

  2. Procedure for Balancing an Air Distribution System with Decentralised Fans

    DEFF Research Database (Denmark)

    Gunner, Amalie; Hultmark, Göran; Vorre, Anders

    2015-01-01

    flawed. This paper presents a new procedure for balancing of CAV systems in combination with decentralised fans. The new system was based on replacing the balancing dampers with decentralised fans. By replacing the balancing dampers with decentralised fans, airflows can be balanced by adjusting the speed...... of the fans. In conventional air distribution systems the fan provides the necessary pressure to overcome the resistance in the branch with the highest pressure resistance. This gives an unnecessary overpressure in the remaining branches that does not provide any useful purpose. In order to decrease the fan...... pressure requirements the fan was dimensioned for the branch with the least pressure resistance. The decentralised fans then provided sufficient pressure to overcome the exact resistance in the corresponding branch. The results show that by using decentralised fans in duct systems instead of dampers...

  3. Measurement of Ambient Air Motion of D. I. Gasoline Spray by LIF-PIV

    Science.gov (United States)

    Yamakawa, Masahisa; Isshiki, Seiji; Yoshizaki, Takuo; Nishida, Keiya

    Ambient air velocity distributions in and around a D. I. gasoline spray were measured using a combination of LIF and PIV techniques. A rhodamine and water solution was injected into ambient air to disperse the fine fluorescent liquid particles used as tracers. A fuel spray was injected into the fluorescent tracer cloud and was illuminated by an Nd: YAG laser light sheet (532nm). The scattered light from the spray droplets and tracers was cut off by a high-pass filter (>560nm). As the fluorescence (>600nm) was transmitted through the high-pass filter, the tracer images were captured using a CCD camera and the ambient air velocity distribution could be obtained by PIV based on the images. This technique was applied to a D. I. gasoline spray. The ambient air flowed up around the spray and entered into the tail of the spray. Furthermore, the relative velocity between the spray and ambient air was investigated.

  4. Crowdsourcing urban air temperature measurements using smartphones

    Science.gov (United States)

    Balcerak, Ernie

    2013-10-01

    Crowdsourced data from cell phone battery temperature sensors could be used to contribute to improved real-time, high-resolution air temperature estimates in urban areas, a new study shows. Temperature observations in cities are in some cases currently limited to a few weather stations, but there are millions of smartphone users in many cities. The batteries in cell phones have temperature sensors to avoid damage to the phone.

  5. Measure Guideline. Air Sealing Attics in Multifamily Buildings

    Energy Technology Data Exchange (ETDEWEB)

    Otis, Casey [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Maxwell, Sean [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2012-06-01

    This Building America Measure Guideline is intended for owners, builders, contractors, homeowners, and other stakeholders in the multifamily building industry, and focuses on challenges found in existing buildings for a variety of housing types. It explains why air sealing is desirable, explores related health and safety issues, and identifies common air leakage points in multifamily building attics. In addition, it also gives an overview of materials and techniques typically used to perform air sealing work.

  6. Clean Air Act Standards and Guidelines for Chemical Production and Distribution

    Science.gov (United States)

    This page contains the stationary sources of air pollution for the chemical production & distribution industries, and their corresponding air pollution regulations. To learn more about the regulations for each industry, click on the links below.

  7. Quantum key distribution without alternative measurements

    CERN Document Server

    Cabello, A

    2000-01-01

    Entanglement swapping between Einstein-Podolsky-Rosen (EPR) pairs can be used to generate the same sequence of random bits in two remote places. A quantum key distribution protocol based on this idea is described. The scheme exhibits the following features. (a) It does not require that Alice and Bob choose between alternative measurements, therefore improving the rate of generated bits by transmitted qubit. (b) It allows Alice and Bob to generate a key of arbitrary length using a single quantum system (three EPR pairs), instead of a long sequence of them. (c) Detecting Eve requires the comparison of fewer bits. (d) Entanglement is an essential ingredient. The scheme assumes reliable measurements of the Bell operator. (20 refs).

  8. Dynamics of electricity efficiency in commercial air-distribution systems in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Christiansson, Lena

    1996-04-01

    This paper illustrates the long-term potential for reducing future electricity demand for air-distribution in commercial buildings in Sweden. The objective has been to develop a general quantitative scenario-based framework to describe some possible paths for electricity demand for air distribution and to analyze how governmental and utility-sponsored policy measures can affect electricity demand. The focus is on improved electricity efficiency, i.e. a reduction of electricity demand for the same level of services. The results suggest that higher electricity prices will not be very effective in reducing electricity demand, whereas significant electricity savings can be reached by implementing various policy programs, particularly standards. 56 refs, 4 figs, 5 tabs

  9. Trends in natural gas distribution and measurements

    International Nuclear Information System (INIS)

    Crone, C.F.A.

    1993-01-01

    On the occasion of the GAS EXPO 93, to be held from 13-15 October 1993 in Amsterdam, Netherlands, an overview is given of trends in the distribution of natural gas and the measuring of natural gas, as noted by experts from the energy utilities, GASTEC and Gasunie in the Netherlands. With regard to the natural gas distribution trends attention is paid to synthetic materials, the environmental effects, maintenance, underground natural gas pressure control, horizontal drilling (no-dig techniques), and other trends. With regard to natural gas metering trends brief discussions are given of the direct energy meter, the search for a new gas meter in households, telemetering, improving the accuracy of the gas meters by means of electronics, on the spot calibration of large gas meters, the use of an online chromatograph to determine the calorific value, the development of a calibration instrument, the so-called piston prover, to measure large quantities of natural gas, the recalibration of natural gas stations, the ultrasonic gas meter, and finally the quality of the natural gas supply. 1 fig., 11 ills

  10. The effect of a photocatalytic air purifier on indoor air quality quantified using different measuring methods

    DEFF Research Database (Denmark)

    Kolarik, Barbara; Wargocki, Pawel; Skorek-Osikowska, A.

    2010-01-01

    The effect on indoor air quality of an air purifier based on photocatalytic oxidation (PCO) was determined by different measuring techniques: sensory assessments of air quality made by human subjects, Proton-Transfer-Reaction Mass Spectrometry (PTR-MS) and chromatographic methods (Gas......, additional measurements were made with no pollution sources present in the office. All conditions were tested with the photocatalytic air purifier turned on and off. The results show that operation of the air purifier in the presence of pollutants emitted by building materials and furniture improves indoor...... Chromatography/Mass Spectrometry and High-Pressure Liquid Chromatography with UV detection). The experiment was conducted in a simulated office, ventilated with 0.6 h(-1), 2.5 h(-1) and 6 h(-1), in the presence of additional pollution sources (carpet, chipboard and linoleum). At the lowest air change rate...

  11. Confounding and exposure measurement error in air pollution epidemiology

    NARCIS (Netherlands)

    Sheppard, L.; Burnett, R.T.; Szpiro, A.A.; Kim, J.Y.; Jerrett, M.; Pope, C.; Brunekreef, B.|info:eu-repo/dai/nl/067548180

    2012-01-01

    Studies in air pollution epidemiology may suffer from some specific forms of confounding and exposure measurement error. This contribution discusses these, mostly in the framework of cohort studies. Evaluation of potential confounding is critical in studies of the health effects of air pollution.

  12. Measurement of the refraction Index of air using Interference refractometers

    NARCIS (Netherlands)

    Schellekens, P.H.J.; Wilkening, G.; Reinboth, F.; Downs, M.J.; Birch, K.P.; Spronck, J.

    1986-01-01

    Comparisons have been carried out between interference refractometers built in different countries. Individual measurements of the refractive index of air have been made using air from the same sample volume. Direct comparison of refractometers was realized by coupling the instruments to the same

  13. Measurement of oxygen transfer from air into organic solvents

    DEFF Research Database (Denmark)

    Ramesh, Hemalata; Mayr, Torsten; Hobisch, Mathias

    2016-01-01

    biological reactions require the supply of oxygen, most normally from air. However, reliable on-line measurements of oxygen concentration in organic solvents (and hence oxygen transfer rates from air to the solvent) has to date proven impossible due limitations in the current analytical methods. Results...... applications). Subsequently, we measured the oxygen transfer rates from air into these organic solvents. Conclusion The measurement of oxygen transfer rates from air into organic solvents using the dynamic method was established using the solvent resistant optical sensor. The feasibility of online oxygen...... For the first time, we demonstrate on-line oxygen measurements in non-aqueous media using a novel optical sensor. The sensor was used to measure oxygen concentration in various organic solvents including toluene, THF, isooctane, DMF, heptane and hexane (which have all been shown suitable for several biological...

  14. Spectrally resolved pressure dependence measurements of air fluorescence emission with AIRFLY

    International Nuclear Information System (INIS)

    Ave, M.; Bohacova, M.; Buonomo, B.; Busca, N.; Cazon, L.; Chemerisov, S.D.; Conde, M.E.; Crowell, R.A.; Di Carlo, P.; Di Giulio, C.; Doubrava, M.; Esposito, A.; Facal, P.; Franchini, F.J.; Hoerandel, J.; Hrabovsky, M.; Iarlori, M.; Kasprzyk, T.E.; Keilhauer, B.; Klages, H.

    2008-01-01

    The knowledge of the fluorescence emission as a function of atmospheric parameters is essential for the detection of extensive air showers with the fluorescence technique. In this paper, we summarize AIRFLY published measurements of the pressure dependence of the fluorescence yield. The spectral distribution of the fluorescent light between 280 and 429 nm has been measured with high resolution. Relative intensities of 34 spectral lines have been determined. The pressure dependence of 25 lines was measured in terms of quenching reference pressures p λ ' in air. This set of AIRFLY measurements yields the most comprehensive parametrization of the pressure dependence of the fluorescent spectrum.

  15. Measurement of radon concentration in air employing Lucas chamber

    International Nuclear Information System (INIS)

    Machaj, B.

    1997-01-01

    The results of investigations aimed to determine the main features of radon concentration gauge in air, employing 0.17 L Lucas chamber, and air sample forced by an air pump are presented. For two hour sampling and measuring cycle time the dynamic error in the worst case (first read out) equals 5 % relative to the step jump of radon concentration. This is due to the increase of activity of the decay products in the chamber. It was observed that the short lived radon decay products (Po-218, Pb-214, Bi-214) are depositing on the walls of the chamber and they are not removed by flushing the chamber with air. (author)

  16. Air Force Maintenance Technician Performance Measurement.

    Science.gov (United States)

    1979-12-28

    aMbr) ATTACHED DD , . - , .147-3 ",, EDITIoN o Fo NOV 66 IS O SOLETE 8,C) 9iCLAS S I r! ABSTRA CT Title: AIR FORCE MAINTENANCE T-,-NIIAN PERFCRMANCZ M...directions have 43 been edited to c’-nf:rm to Uhrbrock’s (1961) rules for a-zraisai forms, i.e., thoup-hts are expressed clearly and si-z!y, staze- ments...Yillarl, -Iheed 19 ,4., F. 1-ut .h ..s, ar .L . ’I’t-.man- -...." , e 3reakthrough for ?erfcrmance .- aisa !." 3usiness Horizons, 1076, 1, 66-73. Yiner, J

  17. Side abutment pressure distribution by field measurement

    Energy Technology Data Exchange (ETDEWEB)

    Lian-guo Wang; Yang Song; Xing-hua He; Jian Zhang [State Key Laboratory for Geomechanics and Deep Underground Engineering, Xuzhou (China)

    2008-12-15

    Given the 7123 working face in the Qidong Coal Mine of the Wanbei Mining Group, nine dynamic roof monitors were installed in the crossheading to measure the amount and velocity of roof convergence in different positions and at different times and three steel bored stress sensors were installed in the return airway to measure rock stress at depth. On the basis of this arrangement, the rule of change of the distribution of the side abutment pressure with the advance of the working face and movement of overlying strata was studied. The rule of change and the stability of rock stress at depth were measured. Secondly, the affected area and stability time of the side abutment pressure were also studied. The results show that: 1) During working, the face advanced distance was from 157 m to 99 m, the process was not effected by mining induced pressure. When the distance was 82 m, the position of peak stress was 5 m away from the coal wall. When the distance was 37 m, the position of peak stress away from the coal wall was about 15 m to 20 m and finally reached a steady state; 2) the time and the range of the peak of side rock pressure obtained from stress sensors were consistent with the results from the dynamic roof monitors; 3) the position of the peak pressure was 25 m away from the coal wall. 14 refs., 6 figs.

  18. Radiation measurement of civil air flight

    International Nuclear Information System (INIS)

    Winter, M.

    1999-01-01

    In order to aquire knowledge of the radiation exposure of civil aircrew members in common flight altitudes, it was necessary to develop a practicable measurement system. Radiation exposure was hereby estimated by using the ACREM-System, which is patented by the Austrian Research Centres Seibersdorf (OEFZS). Total Equivalent Dose could be estimated in a simple way by combining a measured component of the radiation field in flight altitudes and the results of simulation with LUIN 94 particle transport code (Keran O'Brian). To verify the results of the measurement system, a tissue equivalent proportional counter (TEPC) was used. Because of the difficult measurement conditions in cargo airplanes, special attention had to be taken to make the measurement equipment easy to use and transport. Special software has been developed to automate the measurement and the evaluation of the large amount of collected data. Measurements in standard calibration photon fields for the characterization of the equipment could be performed at the Primary Dosimetry Laboratory for Austria at the Austrian Research Centre (OEFZS) in Seibersdorf. Additional measurements were performed at Physikalisch Technische Bundesanstalt Braunschweig (PTB, Germany) and Paul Scherer Institute (PSI, Switzerland) to determine the reponse of the instruments to high energy photon and standard neutron fields. (author)

  19. Air Temperature Measurements Using Dantec Draught Probes

    DEFF Research Database (Denmark)

    Kristensen, Martin Heine; Jensen, Jakob Søland; Jensen, Rasmus Lund

    This technical report is written based on investigations of Dantec measurement equipment used in a master thesis project by the authors in the period September 2014 to June 2015 (Kristensen & Jensen, 2015).......This technical report is written based on investigations of Dantec measurement equipment used in a master thesis project by the authors in the period September 2014 to June 2015 (Kristensen & Jensen, 2015)....

  20. Development of alpha radioactivity measurement using ionized air transportation technology

    International Nuclear Information System (INIS)

    Kanemoto, Shigeru; Naito, Susumu; Sano, Akira; Sato, Mitsuyoshi; Fukumoto, Masahiko; Miyamoto, Yasuaki; Nanbu, Kenichi; Takahashi, Hiroyuki

    2005-01-01

    Alpha radioactivity Measurement using ionized Air Transportation technology (AMAT) is developed to measure alpha contaminated wastes with large and complex surfaces. An outline of this project was described in this text. A major problem of AMAT technology is that the theoretical relation between alpha radioactivity and observed ion current is unclear because of the complicated behavior of ionized air molecules. An ion current prediction model covering from ionization of air molecules to ion detection was developed based on atmospheric electrodynamics. This model was described in this text, too. (author)

  1. Estimations of distribution and zoning for air temperature using satellite data over Liaoning province, China

    International Nuclear Information System (INIS)

    Wang, X.; Horiguchi, I.; Takeda, T.; Yazawa, M.; Liu, X.; Yang, Y.; Wang, Q.

    1999-01-01

    The distribution and zoning of air temperature over Liaoning Province, China were examined using the calculated values of air temperature derived from satellite data (GMS data) as well as from altitude data. The results are summarized as follows. At 02:00 LST the correlation coefficients for the air temperatures calculated from altitude compared with the observed air temperatures were the same as those of the air temperatures derived from GMS data. At 14:00 LST, however, the correlation coefficients for air temperatures calculated from altitude were less than those of the air temperatures derived from GMS data. This fact verifies that the distribution of air temperature in the day-time is affected by other factors than altitude. The distribution of air temperature in a cell of approximately 5'(latitude) x 7.5'(longitude) over Liaoning Province, china was estimated by using the regression equations between surface temperature derived from GMS and the observed air temperature. The distribution of air temperature was classified into 5 types, and the types are obtained at 14:00 LST are seasonal ones but the types at 02:00 LST are not related to season. Also, the regional classification for the air temperature was examined using this distribution of air temperature. This regional classification for the air temperature was similar to the published zoning of the agricultural climate. It became clear that the characteristic distribution of air temperature in a cell unit can be obtained by satellite data. And it is possible to define the zoning of air temperature for a cell unit by the accumulated analyses of satellite data over an extended period

  2. Real time measurement of air radioactivity

    International Nuclear Information System (INIS)

    Galeriu, D.; Craciunescu, T.; Teles, S.

    1998-01-01

    A Local Meteorological and Radiological Monitoring System was developed in our institute for several purposes: local monitoring, extending our experience in other location such as Cernavoda NPP and research. This system has meteorological sensors for wind speed and direction, air temperature, solar radiation, relative humidity, rainfall, dose ratemeter (Geiger-Muller counter - TIEX), Alpha-Beta Activity-in-Air Monitor (AB96), Iodine Monitor and Eberline Intelligent Ionization Chamber (FHT 6010). All data are collected by a programmable interface Delta-T Logger that is controlled by a software (ODAS - 'On-line Data Acquisition Software'). ODAS was developed in IFIN-HH. It has the capability to acquire, calculate and transmit real meteorological and radiological data through local network. The developed software controls the interface, the flux of input data through the serial port RS232 and after some processing (system, configuration, input data, connection to the network checking, etc) it creates data files. These files are transmitted on-line to our workstation or in any other place connected to Internet. Data can be collected from the logger at any time during logging. There is no need to stop logging. Data output from the logger can be controlled either from the logger's keypad or from other user terminals. ODAS is operated as follows: - First, the last written file and the date-time of acquired readings are checked. For establishing communication with logger a RS232 level signal must be sent to it. The logger wakes if asleep and sends back RDY signal. Powering the logger may take up to 100 ms to establish a correct RS232 level. Noise on the output lines occurs during this period and communication software may need to take into account such spurious signals. A command must be sent to the logger within 2 s to confirm that the last signal received is real and not spurious. Otherwise, the logger interprets the signal as noise and sleeps. The software sends further

  3. Rural southeast Texas air quality measurements during the 2006 Texas Air Quality Study.

    Science.gov (United States)

    Schade, Gunnar W; Khan, Siraj; Park, Changhyoun; Boedeker, Ian

    2011-10-01

    The authors conducted air quality measurements of the criteria pollutants carbon monoxide, nitrogen oxides, and ozone together with meteorological measurements at a park site southeast of College Station, TX, during the 2006 Texas Air Quality Study II (TexAQS). Ozone, a primary focus of the measurements, was above 80 ppb during 3 days and above 75 ppb during additional 8 days in summer 2006, suggestive of possible violations of the ozone National Ambient Air Quality Standard (NAAQS) in this area. In concordance with other air quality measurements during the TexAQS II, elevated ozone mixing ratios coincided with northerly flows during days after cold front passages. Ozone background during these days was as high as 80 ppb, whereas southerly air flows generally provided for an ozone background lower than 40 ppb. Back trajectory analysis shows that local ozone mixing ratios can also be strongly affected by the Houston urban pollution plume, leading to late afternoon ozone increases of as high as 50 ppb above background under favorable transport conditions. The trajectory analysis also shows that ozone background increases steadily the longer a southern air mass resides over Texas after entering from the Gulf of Mexico. In light of these and other TexAQS findings, it appears that ozone air quality is affected throughout east Texas by both long-range and regional ozone transport, and that improvements therefore will require at least a regionally oriented instead of the current locally oriented ozone precursor reduction policies.

  4. Measurement of the temperature Gradient in air using Talbot effect and Moire technique

    International Nuclear Information System (INIS)

    Tavassoly, M.T.; Rasouli, S.

    2000-01-01

    In this paper we have exploited the self-imaging or Talbot effect and Moire technique to measure the temperature distribution in the air enclosed between two paral led plates of different temperatures. This study shows that for the plates width of 60 cm a change of 1 d egC in 1 cm can be easily detected

  5. A three-dimensional mathematical model to predict air-cooling flow and temperature distribution of wire loops in the Stelmor air-cooling system

    International Nuclear Information System (INIS)

    Hong, Lingxiang; Wang, Bo; Feng, Shuai; Yang, Zhiliang; Yu, Yaowei; Peng, Wangjun; Zhang, Jieyu

    2017-01-01

    Highlights: • A 3-dimentioanl mathematical models for complex wire loops was set up in Stelmor. • The air flow field in the cooling process was simulated. • The convective heat transfer coefficient was simulated coupled with air flow field. • The temperature distribution with distances was predicted. - Abstract: Controlling the forced air cooling conditions in the Stelmor conveyor line is important for improving the microstructure and mechanical properties of steel wire rods. A three-dimensional mathematical model incorporating the turbulent flow of the cooling air and heat transfer of the wire rods was developed to predict the cooling process in the Stelmor air-cooling line of wire rolling mills. The distribution of cooling air from the plenum chamber and the forced convective heat transfer coefficient for the wire loops were simulated at the different locations over the conveyor. The temperature profiles and cooling curves of the wire loops in Stelmor conveyor lines were also calculated by considering the convective heat transfer, radiative heat transfer as well as the latent heat during transformation. The calculated temperature results using this model agreed well with the available measured results in the industrial tests. Thus, it was demonstrated that this model can be useful for studying the air-cooling process and predicting the temperature profile and microstructure evolution of the wire rods.

  6. Use of electrochemical sensors for measurement of air pollution: correcting interference response and validating measurements

    Directory of Open Access Journals (Sweden)

    E. S. Cross

    2017-09-01

    Full Text Available The environments in which we live, work, and play are subject to enormous variability in air pollutant concentrations. To adequately characterize air quality (AQ, measurements must be fast (real time, scalable, and reliable (with known accuracy, precision, and stability over time. Lower-cost air-quality-sensor technologies offer new opportunities for fast and distributed measurements, but a persistent characterization gap remains when it comes to evaluating sensor performance under realistic environmental sampling conditions. This limits our ability to inform the public about pollution sources and inspire policy makers to address environmental justice issues related to air quality. In this paper, initial results obtained with a recently developed lower-cost air-quality-sensor system are reported. In this project, data were acquired with the ARISense integrated sensor package over a 4.5-month time interval during which the sensor system was co-located with a state-operated (Massachusetts, USA air quality monitoring station equipped with reference instrumentation measuring the same pollutant species. This paper focuses on validating electrochemical (EC sensor measurements of CO, NO, NO2, and O3 at an urban neighborhood site with pollutant concentration ranges (parts per billion by volume, ppb; 5 min averages, ±1σ: [CO]  =  231 ± 116 ppb (spanning 84–1706 ppb, [NO]  =  6.1 ± 11.5 ppb (spanning 0–209 ppb, [NO2]  =  11.7 ± 8.3 ppb (spanning 0–71 ppb, and [O3]  =  23.2 ± 12.5 ppb (spanning 0–99 ppb. Through the use of high-dimensional model representation (HDMR, we show that interference effects derived from the variable ambient gas concentration mix and changing environmental conditions over three seasons (sensor flow-cell temperature  =  23.4 ± 8.5 °C, spanning 4.1 to 45.2 °C; and relative humidity  =  50.1 ± 15.3 %, spanning 9.8–79.9

  7. The Performance of Diffuse Ceiling Inlet and other Room Air Distribution Systems

    DEFF Research Database (Denmark)

    Nielsen, Peter V.; Jakubowska, Ewa

    2009-01-01

    The paper analyses different room air distribution systems, and describes a design chart which can be used for the evaluation of variables as air quality, air velocity and temperature gradient as a function of flow rate and temperature difference in the supply system. The design chart can also be...

  8. Test of Different Air Distribution Concepts for a Single-Aisle Aircraft Cabin

    DEFF Research Database (Denmark)

    Nielsen, Peter V.; Damsgaard, Charlotte; Liu, Li

    2013-01-01

    Traditionally, air is supplied to the aircraft cabin either by individual nozzles or by supply slots. The air is expected to be fully mixed in the cabin, and the system is considered to be a mixing ventilation system. This paper will describe different air distribution systems known from other ap...

  9. Femtosecond frequency comb based distance measurement in air.

    Science.gov (United States)

    Balling, Petr; Kren, Petr; Masika, Pavel; van den Berg, S A

    2009-05-25

    Interferometric measurement of distance using a femtosecond frequency comb is demonstrated and compared with a counting interferometer displacement measurement. A numerical model of pulse propagation in air is developed and the results are compared with experimental data for short distances. The relative agreement for distance measurement in known laboratory conditions is better than 10(-7). According to the model, similar precision seems feasible even for long-distance measurement in air if conditions are sufficiently known. It is demonstrated that the relative width of the interferogram envelope even decreases with the measured length, and a fringe contrast higher than 90% could be obtained for kilometer distances in air, if optimal spectral width for that length and wavelength is used. The possibility of comb radiation delivery to the interferometer by an optical fiber is shown by model and experiment, which is important from a practical point of view.

  10. Assessment of operating room air distribution in a mobile hospital: field experiment based on VDI 2167

    NARCIS (Netherlands)

    Forejt, L.; Drkal, F.; Hensen, J.L.M.; Seppänen, O.; Säteri, J.

    2007-01-01

    Air distribution in mobile operating room was assessed according to the recent acceptance test (VDI, 2004 [1]). This standard presents a simple and uniform validation procedure of operating room air distribution systems. Therefore it was applied as an objective method for evaluating performance of

  11. Particle size distributions of radioactive aerosols measured in workplaces

    International Nuclear Information System (INIS)

    Dorrian, M.-D.; Bailey, M.R.

    1995-01-01

    A survey of published values of Activity Median Aerodynamic Diameter (AMAD) measured in working environments was conducted to assist in the selection of a realistic default AMAD for occupational exposures. Results were compiled from 52 publications covering a wide variety of industries and workplaces. Reported values of AMAD from all studies ranged from 0.12 μm to 25 μm, and most were well fitted by a log-normal distribution with a median value of 4.4 μm. This supports the choice of a 5 μm default AMAD, as a realistic rounded value for occupational exposures, by the ICRP Task Group on Human Respiratory Tract Models for Radiological Protection and its acceptance by ICRP. Both the nuclear power and nuclear fuel handling industries gave median values of approximately 4 μm. Uranium mills gave a median value of 6.8 μm with AMADs frequently greater than 10 μm. High temperature and arc saw cutting operations generated submicron particles and occasionally, biomodal log-normal particle size distributions. It is concluded that in view of the wide range of AMADs found in the surveyed literature, greater emphasis should be placed on air sampling to characterise aerosol particle size distributions for individual work practices, especially as doses estimated with the new 5 μm default AMAD will not always be conservative. (author)

  12. Fault-tolerant distributed measurement systems

    Energy Technology Data Exchange (ETDEWEB)

    Gater, C.

    1987-01-01

    A 100 kbit/s battery-powered fault-tolerant communications network was developed for use in industrial distributed measurement systems, where a loop controller supervises up to 64 addressable field devices with a network polling period of 250ms. Safety and reliability were optimized using fibre-optic data links and low-power circuitry throughout. Based on a highly redundant loop topology of two receiver/two transmitter communications nodes, the network can tolerate any double node or any quadruple linked failure. Each node circuit is designed to operate continuously for five years using a standard D-type lithium cell, and consists essentially of a CMOS single-chip microcomputer, a specially designed CMOS communications interface chip, some analogue circuity for the optical receivers and transmitters, and interfaces for a sensor/actuator and roving hand-held terminal. The communications interface was implement on a 2436-cell CMOS gate array and feature a self-test facility which provides over 86% fault coverage using only three test vectors. The chip can also be used in the loop controller. Control procedures developed to detect, locate, and reconfigure around faults that occur in the communications network.

  13. Decontamination evaluation based on radioactivity measurement instead of air dose rate

    International Nuclear Information System (INIS)

    Shozugawa, Katsumi

    2013-01-01

    Air dose rate at 1 m above the ground comes from gamma radiations emitted from vast area ranging over several ten meters of the contaminated field from the counter. After showing the actual example of the difference between air dose rate data and Cs 137 distribution map made by using a shielded NaI-scintillation counter within and around a contaminated sinkhole (a ditch or trench) near Fukushima Daiichi Nuclear Power Plants, the author proposes to make a decontamination program according to the radioactivity distribution measurement instead of air dose rate measurement. Furthermore, he explains some problems arising from a point and plane radiation source, and also difficulties accompanied by movement of Cs 137 atoms in the soils according to the absorption characteristics of the existing minerals but these are also important to consider for performing an effective decontamination. (S. Ohno)

  14. Measurement of the concentration of radon in the air

    International Nuclear Information System (INIS)

    Aten, J.B.Th.; Bierhuizen, H.W.J.; Hoek, L.P. van; Ros, D.; Weber, J.

    1975-01-01

    A simple transportable air monitoring apparatus was developed for controlling the radon contamination of air in laboratory rooms. It is not highly accurate but is sufficient to register the order of magnitude of the radon concentration. Air is pumped through a filter for one or two hours and an alpha decay curve of the dust on the filter is determined. Scintillation counting forty minutes after sampling indicates the radon activity. The calibration method of measuring the equilibrium of daughter product concentrations is discussed extensively

  15. A mixing method for traceable air velocity measurements

    International Nuclear Information System (INIS)

    Sillanpää, S; Heinonen, M

    2008-01-01

    A novel and quite simple method to establish a traceability link between air velocity and the national standards of mass and time is presented in this paper. The method is based on the humidification of flowing air before the blower of a wind tunnel with a known mass flow of water. Then air velocity can be calculated as a function of humidification water flow. The method is compared against a Pitot-tube-based velocity measurement in a wind tunnel at the MIKES. The results of these two different methods agreed well, with a maximum difference of 0.7%

  16. An under-aisle air distribution system facilitating humidification of commercial aircraft cabins

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Tengfei; Yin, Shi; Wang, Shugang [School of Civil and Hydraulic Engineering, Dalian University of Technology (DUT), 2 Linggong Road, Dalian 116024 (China)

    2010-04-15

    Air environment in aircraft cabins has long been criticized especially for the dryness of the air within. Low moisture content in cabins is known to be responsible for headache, tiredness and many other non-specific symptoms. In addition, current widely used air distribution systems on airplanes dilute internally generated pollutants by promoting air mixing and thus impose risks of infectious airborne disease transmission. To boost air humidity level while simultaneously restricting air mixing, this investigation uses a validated computational fluid dynamics (CFD) program to design a new under-aisle air distribution system for wide-body aircraft cabins. The new system supplies fully outside, dry air at low momentum through a narrow channel passage along both side cabin walls to middle height of the cabin just beneath the stowage bins, while simultaneously humidified air is supplied through both perforated under aisles. By comparing with the current mixing air distribution system in terms of distribution of relative humidity, CO{sub 2} concentration, velocity, temperature and draught risk, the new system is found being able to improve the relative humidity from the existent 10% to the new level of 20% and lessen the inhaled CO{sub 2} concentration by 30%, without causing moisture condensation on cabin interior and inducing draught risks for passengers. The water consumption rate in air humidification is only around 0.05 kg/h per person, which should be affordable by airliners. (author)

  17. Air encapsulation. I. Measurement in a field soil

    International Nuclear Information System (INIS)

    Fayer, M.J.; Hillel, D.

    1986-01-01

    Encapsulated air is an important component of shallow water table fluctuations. Their objective was to measure the quantity and persistence of encapsulated air in a field setting. Using sprinkling rates of either 3.5 x 10 -6 or 3.8 x 10 -5 m s -1 , they brought the water table in a field soil from a depth of 1.5 m to the surface on several occasions. Moisture contents during and after sprinkling were monitored with a neutron probe. Twice following sprinkling, the water table was maintained at the surface for more than 20 d, during which time they continued to monitor moisture contents. With the water table at the surface, differences between the porosity and the measured moisture content were attributed to encapsulated air. Encapsulated air contents ranged from 1.1 to 6.3% of the bulk soil volume, depending on the rate of sprinkling, soil depth, and initial soil moisture content. During ponding, encapsulated air persisted at the 0.3-m depth for up to 28 d. The results indicate that encapsulated air is measurable in a field situation and that its quantity and persistence should be considered in analyzing the results of similar field experiments. 16 references

  18. Aspirated capacitor measurements of air conductivity and ion mobility spectra

    International Nuclear Information System (INIS)

    Aplin, K.L.

    2005-01-01

    Measurements of ions in atmospheric air are used to investigate atmospheric electricity and particulate pollution. Commonly studied ion parameters are (1) air conductivity, related to the total ion number concentration, and (2) the ion mobility spectrum, which varies with atmospheric composition. The physical principles of air ion instrumentation are long established. A recent development is the computerized aspirated capacitor, which measures ions from (a) the current of charged particles at a sensing electrode, and (b) the rate of charge exchange with an electrode at a known initial potential, relaxing to a lower potential. As the voltage decays, only ions of higher and higher mobility are collected by the central electrode and contribute to the further decay of the voltage. This enables extension of the classical theory to calculate ion mobility spectra by inverting voltage decay time series. In indoor air, ion mobility spectra determined from both the voltage decay inversion, and an established voltage switching technique, were compared and shown to be of similar shape. Air conductivities calculated by integration were: 5.3±2.5 and 2.7±1.1 fSm -1 , respectively, with conductivity determined to be 3 fSm -1 by direct measurement at a constant voltage. Applications of the relaxation potential inversion method include air ion mobility spectrum retrieval from historical data, and computation of ion mobility spectra in planetary atmospheres

  19. The Aeroflex: A Bicycle for Mobile Air Quality Measurements

    Science.gov (United States)

    Elen, Bart; Peters, Jan; Van Poppel, Martine; Bleux, Nico; Theunis, Jan; Reggente, Matteo; Standaert, Arnout

    2013-01-01

    Fixed air quality stations have limitations when used to assess people's real life exposure to air pollutants. Their spatial coverage is too limited to capture the spatial variability in, e.g., an urban or industrial environment. Complementary mobile air quality measurements can be used as an additional tool to fill this void. In this publication we present the Aeroflex, a bicycle for mobile air quality monitoring. The Aeroflex is equipped with compact air quality measurement devices to monitor ultrafine particle number counts, particulate mass and black carbon concentrations at a high resolution (up to 1 second). Each measurement is automatically linked to its geographical location and time of acquisition using GPS and Internet time. Furthermore, the Aeroflex is equipped with automated data transmission, data pre-processing and data visualization. The Aeroflex is designed with adaptability, reliability and user friendliness in mind. Over the past years, the Aeroflex has been successfully used for high resolution air quality mapping, exposure assessment and hot spot identification. PMID:23262484

  20. Femtosecond frequency comb based distance measurement in air

    NARCIS (Netherlands)

    Balling, P.; Kren, P.; Masika, P.; van den Berg, S.A.

    2009-01-01

    Interferometric measurement of distance using a femtosecond frequency comb is demonstrated and compared with a counting interferometer displacement measurement. A numerical model of pulse propagation in air is developed and the results are compared with experimental data for short distances. The

  1. Confounding and exposure measurement error in air pollution epidemiology.

    Science.gov (United States)

    Sheppard, Lianne; Burnett, Richard T; Szpiro, Adam A; Kim, Sun-Young; Jerrett, Michael; Pope, C Arden; Brunekreef, Bert

    2012-06-01

    Studies in air pollution epidemiology may suffer from some specific forms of confounding and exposure measurement error. This contribution discusses these, mostly in the framework of cohort studies. Evaluation of potential confounding is critical in studies of the health effects of air pollution. The association between long-term exposure to ambient air pollution and mortality has been investigated using cohort studies in which subjects are followed over time with respect to their vital status. In such studies, control for individual-level confounders such as smoking is important, as is control for area-level confounders such as neighborhood socio-economic status. In addition, there may be spatial dependencies in the survival data that need to be addressed. These issues are illustrated using the American Cancer Society Cancer Prevention II cohort. Exposure measurement error is a challenge in epidemiology because inference about health effects can be incorrect when the measured or predicted exposure used in the analysis is different from the underlying true exposure. Air pollution epidemiology rarely if ever uses personal measurements of exposure for reasons of cost and feasibility. Exposure measurement error in air pollution epidemiology comes in various dominant forms, which are different for time-series and cohort studies. The challenges are reviewed and a number of suggested solutions are discussed for both study domains.

  2. Measurement of air and VOC vapor fluxes during gas-driven soil remediation: bench-scale experiments.

    Science.gov (United States)

    Kim, Heonki; Kim, Taeyun; Shin, Seungyeop; Annable, Michael D

    2012-09-04

    In this laboratory study, an experimental method was developed for the quantitative analyses of gas fluxes in soil during advective air flow. One-dimensional column and two- and three-dimensional flow chamber models were used in this study. For the air flux measurement, n-octane vapor was used as a tracer, and it was introduced in the air flow entering the physical models. The tracer (n-octane) in the gas effluent from the models was captured for a finite period of time using a pack of activated carbon, which then was analyzed for the mass of n-octane. The air flux was calculated based on the mass of n-octane captured by the activated carbon and the inflow concentration. The measured air fluxes are in good agreement with the actual values for one- and two-dimensional model experiments. Using both the two- and three-dimensional models, the distribution of the air flux at the soil surface was measured. The distribution of the air flux was found to be affected by the depth of the saturated zone. The flux and flux distribution of a volatile contaminant (perchloroethene) was also measured by using the two-dimensional model. Quantitative information of both air and contaminant flux may be very beneficial for analyzing the performance of gas-driven subsurface remediation processes including soil vapor extraction and air sparging.

  3. Traceable measurements of the activity concentration in air

    CERN Document Server

    Paul, A; Forkel-Wirth, Doris; Müller, A; Marcos, A

    2002-01-01

    The nuclear reactions induced by high energetic protons in heavy targets such as UC/sub 2/ and ThC cause a particular, complex radiation protection task at facilities like ISOLDE: the measurement of a mixture of different isotopes of the radioactive noble gas radon and the radon progenies in air. The knowledge of their respective activity concentration is fundamental for exposure assessments. Due to the complex mixture of activity concentrations in air, its precise determination is quite difficult. Therefore, a new procedure for taking reference samples was developed and implemented for the traceable measurement of the activity concentration of radioactive ions (e.g., radon progenies) in air. This technique is combined by measuring alpha -particles with a multi-wire ionization chamber for the parallel on-line determination of the activity concentration of different radon isotopes. (10 refs).

  4. Measurement of 222Rn in soil concentrations in interstitial air

    International Nuclear Information System (INIS)

    Duenas, C.; Fernandez, M.C.; Carretero, J.; Liger, E.

    1996-01-01

    Measurements of 222 Rn soil concentrations were made by inserting stainless-steel sampling tubes into the soil. The samples of the soil interstitial air were taken in to pre-evacuated 1 L glass flasks. The glass flasks are cylindrical and coated with a film of ZnS(Ag). 222 Rn was measured by counting the alpha particles emitted by 222 Rn and its daughter products, 218 Po and 214 Bi, when they reached radioactive equilibrium. Measurements of 222 Rn gas concentrations in the soil air interstices by the method at different depths were used to calculate the diffusion coefficient of the 222 Rn in the soil air. This study has been carried out for diverse soils. (Author)

  5. Traceable measurements of the activity concentration in air

    International Nuclear Information System (INIS)

    Paul, Annette; Honig, Anja; Forkel-Wirth, Doris; Mueller, Andre; Marcos, Alicia

    2002-01-01

    The nuclear reactions induced by high energetic protons in heavy targets such as UC 2 and ThC cause a particular, complex radiation protection task at facilities like ISOLDE: the measurement of a mixture of different isotopes of the radioactive noble gas radon and the radon progenies in air. The knowledge of their respective activity concentration is fundamental for exposure assessments. Due to the complex mixture of activity concentrations in air, its precise determination is quite difficult. Therefore, a new procedure for taking reference samples was developed and implemented for the traceable measurement of the activity concentration of radioactive ions (e.g., radon progenies) in air. This technique is combined by measuring α-particles with a multi-wire ionization chamber for the parallel on-line determination of the activity concentration of different radon isotopes

  6. Radon in indoor air. Health risk, measurement methods and remedial measures

    International Nuclear Information System (INIS)

    Strand, T.

    1996-02-01

    Radon in indoor air is the main source of ionizing radiation in Norway. The booklet contains a presentation of radon sources, measurement methods, indoor radon concentrations, action levels, health risk and remedial measures

  7. Advanced air distribution: Improving health and comfort while reducing energy use

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor

    2015-01-01

    -quality indoor environments at the same time as low-energy consumption. Advanced air distribution, designed to supply clean air where, when, and as much as needed, makes it possible to efficiently achieve thermal comfort, control exposure to contaminants, provide high-quality air for breathing and minimizing......Indoor environment affects the health, comfort, and performance of building occupants. The energy used for heating, cooling, ventilating, and air conditioning of buildings is substantial. Ventilation based on total volume air distribution in spaces is not always an efficient way to provide high...... the risk of airborne cross-infection while reducing energy use. This study justifies the need for improving the present air distribution design in occupied spaces, and in general the need for a paradigm shift from the design of collective environments to the design of individually controlled environments...

  8. Air Distribution Systems and Cross-Infection Risk in the Hospital Sector

    DEFF Research Database (Denmark)

    Nielsen, Peter V.

    2012-01-01

    . A large amount of air is supplied to the room to ensure dilution of airborne infection. The paper discusses both the macroenvironment and the microenvironment. The macroenvironment is the conditions created by the air distribution system, and the microenvironment is the conditions created by the local...... flow around persons in combination with the surrounding conditions. Analyses of the flow in the room (macroenvironment) show a number of parameters that play an important role in minimising of airborne cross-infection. The air flow rate to the room must be high, and the air distribution pattern can......We protect ourselves from airborne cross-infection in our indoor environment by supplying fresh air to the room by natural or mechanical ventilation. The air is distributed in the room according to different principles as e.g. mixing ventilation, downward ventilation, displacement ventilation, etc...

  9. The air quality in Norwegian cities. Development - reasons - measures - future

    International Nuclear Information System (INIS)

    Larssen, Steinar; Hagen, Leif Otto

    1998-12-01

    There is an increasing focus on the air quality in Norwegian cities and townships. The air quality depends on several factors and the connections are complex. The aim of this report is to present a short and simple survey of this complex field. The report consists of three parts: Part 1 is a survey of the development until today. Measurements of SO 2 and soot were started in the 1950's. Systematic determinations of NO x and NO 2 , CO and particles, ozone and benzene was started during the last three decades. The population exposure to air pollutants and their main sources are described as well as the air quality in Norwegian cities compared to other cities in Europe. In part 2 developments within transport, a sector necessary for understanding the development, are described. Part 3 is a survey of forecasting the air quality in Norway, pollution warnings and surveillance. The forecasts are based on assumed developments in important sectors such as transport, energy consumption for heating and industrial purposes and the effects of demands for fuel and vehicles. Effect analyses of further measures which may be useful for reaching the national goals for the air quality are carried out. A survey of the most important limiting values and criteria as well as technical terms is presented in the report and in the appendix. The report is commissioned by the Norwegian Petroleum Institute (Norsk Petroleumsinstitutt) and the Norwegian Road Federation (Opplysningsraadet for Veitrafikken)

  10. Measurements of environmental policy for air pollution abatement

    International Nuclear Information System (INIS)

    Friedrich, R.

    1993-01-01

    The first part of the study goes into the determination of efficient strategies for the reduction of air pollutants. The developed method is not only derived theoretically but is tested with the concrete example of emissions sources of a German state. The second part goes into the question what the government can do in order to attain that air pollution abatement measures recognized as being efficient will be put into practice. As market economy mechanisms have advantages over central state planning in the allocation of economic resources the question arises if not also for environmental protection market economy tools may contribute to an improvement of the efficiency of air pollution abatement. Therefore the suitability of different tools of environmental policy for the realization of efficient air pollution abatement is investigated and evaluated. This is again not done abstractly but with existing emission sources. (orig./HSCH). 32 figs., 12 tabs [de

  11. Measuring Device for Air Speed in Macroporous Media and Its Application Inside Apple Storage Bins

    Directory of Open Access Journals (Sweden)

    Martin Geyer

    2018-02-01

    Full Text Available In cold storage facilities of fruit and vegetables, airflow is necessary for heat removal. The design of storage facilities influences the air speed in the surrounding of the product. Therefore, knowledge about airflow next to the product is important to plan the layout of cold stores adapted to the requirements of the products. A new sensing device (ASL, Air speed logger is developed for omnidirectional measurement of air speed between fruit or vegetables inside storage bins or in bulk. It consists of four interconnected plastic spheres with 80 mm diameter each, adapted to the size of apple fruit. In the free space between the spheres, silicon diodes are fixed for the airflow measurement based on a calorimetric principle. Battery and data logger are mounted inside the spheres. The device is calibrated in a wind tunnel in a measuring range of 0–1.3 m/s. Air speed measurements in fruit bulks on laboratory scale and in an industrial fruit store show air speeds in gaps between fruit with high stability at different airflow levels. Several devices can be placed between stored products for determination of the air speed distribution inside bulks or bin stacks in a storage room.

  12. Measuring Outdoor Air Intake Rates into Existing Building

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William; Sullivan, Douglas; Cohen, Sebastian; Han, Hwataik

    2009-04-16

    Practical and accurate technologies are needed for continuously measuring and controlling outdoor air (OA) intake rates in commercial building heating, ventilating, and air conditioning (HVAC) systems. This project evaluated two new measurement approaches. Laboratory experiments determined that OA flow rates were measurable with errors generally less than 10 percent using electronic air velocity probes installed between OA intake louver blades or at the outlet face of louvers. High accuracy was maintained with OA flow rates as low as 15 percent of the maximum for the louvers. Thus, with this measurement approach HVAC systems do not need separate OA intakes for minimum OA supply. System calibration parameters are required for each unique combination of louver type and velocity sensor location but calibrations are not necessary for each system installation. The research also determined that the accuracy of measuring OA flow rates with velocity probes located in the duct downstream of the intake louver was not improved by installing honeycomb airflow straighteners upstream of the probes. Errors varied with type of upstream louver, were as high as 100 percent, and were often greater than 25 percent. In conclusion, use of electronic air velocity probes between the blades of OA intake louvers or at the outlet face of louvers is a highly promising means of accurately measuring rates of OA flow into HVAC systems. The use of electronic velocity probes downstream of airflow straighteners is less promising, at least with the relatively small OA HVAC inlet systems employed in this research.

  13. Measurable distributions of unpolarized neutron decay

    International Nuclear Information System (INIS)

    Glueck, F.

    1992-05-01

    Several two- and one-dimensional distributions of unpolarized free neutron decay are calculated. The results of the order-α model independent radiative correction calculations are tabulated numerically. With these corrections the theoretical distributions become precise enough to make possible the determination of the ratio of the axial-vector to the vector weak coupling constants to a precision of ∼0.001. (author) 39 refs.; 7 tabs

  14. Measuring brightness temperature distributions of plasma bunches

    International Nuclear Information System (INIS)

    Kirko, V.I.; Stadnichenko, I.A.

    1981-01-01

    The possibility of restoration of brightness temperature distribution along plasma jet on the base of a simple ultra high- speed photography and subsequent photometric treatment is shown. The developed technique has been applied for finding spectral radiation intensity and brightness temperature of plasma jets of a tubular gas-cumulative charge and explosive plasma compressor. The problem of shock wave front has been successfully solved and thus distribution of above parameters beginning from the region preceeding the shock wave has been obtained [ru

  15. In want of measurements of air pollution from wood smoke

    DEFF Research Database (Denmark)

    Czeskleba-Dupont, Rolf; Czeskleba-Dupont, Solveig

    2007-01-01

    , handy measuring instruments at their disposal, so that the inconvenience from smoke could be analytically documented. The contribution details arguments on serious wood smoke pollution, health problems and  regulations  needed.  Local measurements should be promoted  regarding air pollution from...... of ventilation and fine cracks in the outer walls. In the night people can not air the bedrooms without getting the rooms filled with wood smoke. Until now the regulations of wood smoke have been ineffective. - It would be a great step forward, if local authorities and smoke affected people could have effective...

  16. Air distribution system with the discharge action in the working cavity of downhole air hammer drills

    Science.gov (United States)

    Timonin, VV; Alekseev, SE; Kokoulin, DI; Kubanychbek, B.

    2018-03-01

    It is proposed to carry out pre-mine methane drainage using underground degassing holes made by downhole air hammer drills. The features of downhole air drills are described. The downhole air drill layout with the simple-shape striking part is presented with its pluses and minuses. The researchers point at available options to eliminate the shortcomings. The improved layout of the downhole air hammer drill is suggested. The paper ends with the test data on the prototype air hammer drill, its characteristics and trial drilling results.

  17. Retrieving Vertical Air Motion and Raindrop Size Distributions from Vertically Pointing Doppler Radars

    Science.gov (United States)

    Williams, C. R.; Chandra, C. V.

    2017-12-01

    The vertical evolution of falling raindrops is a result of evaporation, breakup, and coalescence acting upon those raindrops. Computing these processes using vertically pointing radar observations is a two-step process. First, the raindrop size distribution (DSD) and vertical air motion need to be estimated throughout the rain shaft. Then, the changes in DSD properties need to be quantified as a function of height. The change in liquid water content is a measure of evaporation, and the change in raindrop number concentration and size are indicators of net breakup or coalescence in the vertical column. The DSD and air motion can be retrieved using observations from two vertically pointing radars operating side-by-side and at two different wavelengths. While both radars are observing the same raindrop distribution, they measure different reflectivity and radial velocities due to Rayleigh and Mie scattering properties. As long as raindrops with diameters greater than approximately 2 mm are in the radar pulse volumes, the Rayleigh and Mie scattering signatures are unique enough to estimate DSD parameters using radars operating at 3- and 35-GHz (Williams et al. 2016). Vertical decomposition diagrams (Williams 2016) are used to explore the processes acting on the raindrops. Specifically, changes in liquid water content with height quantify evaporation or accretion. When the raindrops are not evaporating, net raindrop breakup and coalescence are identified by changes in the total number of raindrops and changes in the DSD effective shape as the raindrops. This presentation will focus on describing the DSD and air motion retrieval method using vertical profiling radar observations from the Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) central facility in Northern Oklahoma.

  18. Specifics of Building Envelope Air Leakage Problems and Airtightness Measurements

    Directory of Open Access Journals (Sweden)

    Borodinecs Anatolijs

    2016-01-01

    Full Text Available In addition to transmission heat loses the infiltration of outdoor air can cause significant heat losses. The external building envelope should be airtight in order to prevent uncontrolled cold air infiltration. The article analysis modern building materials and structures influence on airtightness. The practical measurements of renovated buildings’ airtightness are presented and compared to non-renovated buildings. In addition paper presents data on airtightness measurements of whole multi apartment building and single apartment in analyzed building taking inco accout properties of building materials. The airtightness of single apartment was evaluated with support pressure in neighbor apartments. The results show that the airtightness measurements of multi apartment building can be evaluated by measuring single apartment on last floor with support pressure in neighbor apartments. The practical measurement of renovated buildings had shown the air leakage rate q50 of typical Latvian construction after renovation is between 2.5 and 2.9 m3/(m2·h. Since the building envelope has to minimize the heat loses (transmission and infiltration and ventilation system either mechanical or natural has to provide necessary air exchange, the building envelope airtightness shouldn’t be dependent on type of ventilation systems.

  19. Incorporation monitoring by measurements of activity concentrations in air

    International Nuclear Information System (INIS)

    Breukelmann, G.; Dalheimer, A.; Dilger, H.; Henrichs, K.

    1997-01-01

    The incorporation monitoring of workers handling actinides is in many cases not possible by individual methods: The sensitivity of bioassay of methods (in vivo, in vitro) is not sufficient to detect amounts as required by the low annual limits of intake. Similar difficulties may occur with the use of radionuclides with very short physical half-lives. In these cases, the measuring of activity concentrations in the air is the only way to monitor the workers and to meet legal requirements. The essential problem connected with this approach is to make sure, that the air sample analyzed represents the average air inhaled actually. Correspondingly, the new system regulating the incorporation monitoring in Germany requires additional measures to ensure this representatively. (author)

  20. Distributional Benefit Analysis of a National Air Quality Rule

    Directory of Open Access Journals (Sweden)

    Jin Huang

    2011-06-01

    Full Text Available Under Executive Order 12898, the U.S. Environmental Protection Agency (EPA must perform environmental justice (EJ reviews of its rules and regulations. EJ analyses address the hypothesis that environmental disamenities are experienced disproportionately by poor and/or minority subgroups. Such analyses typically use communities as the unit of analysis. While community-based approaches make sense when considering where polluting sources locate, they are less appropriate for national air quality rules affecting many sources and pollutants that can travel thousands of miles. We compare exposures and health risks of EJ-identified individuals rather than communities to analyze EPA’s Heavy Duty Diesel (HDD rule as an example national air quality rule. Air pollutant exposures are estimated within grid cells by air quality models; all individuals in the same grid cell are assigned the same exposure. Using an inequality index, we find that inequality within racial/ethnic subgroups far outweighs inequality between them. We find, moreover, that the HDD rule leaves between-subgroup inequality essentially unchanged. Changes in health risks depend also on subgroups’ baseline incidence rates, which differ across subgroups. Thus, health risk reductions may not follow the same pattern as reductions in exposure. These results are likely representative of other national air quality rules as well.

  1. Saving energy by using underfloor-air-distribution (UFAD) system in commercial buildings

    International Nuclear Information System (INIS)

    Alajmi, Ali; El-Amer, Wid

    2010-01-01

    The number of attempts by researchers to reduce building energy consumption has increased, ever since global warming became a serious issue. In this trend, a relatively new approach of air distribution, underfloor-air-distribution system (UFAD), has been widely used in new commercial buildings. This technique is simply accomplished by supplying air through a raised floor using different types of distribution configurations and outlets. In UFAD, the air is directly supplied to the occupants' area (occupied zone) causing occupants plumes and zone heat load stratify to the upper layer of the zone (unoccupied zone), which are later extracted from return points at high level. This flow pattern gives UFAD the advantage of using less energy than a conventional air-distribution system, ceiling-based air distribution (CBAD) due to lower pressure drop and lower air flow rate. This paper investigates the effectiveness of UFAD systems in commercial buildings for various types of application and at different air supply temperatures in a hot climate (The State of Kuwait). The findings show that UFAD has a significant saving of energy compared to CBAD (∼30%); in particular with high ceiling building types, as well as providing satisfactory comfort conditions for the occupants. Ultimately, more investigations should be done on conventional building heights (offices) to optimize the utilization of thermal stratification at design and operation stages.

  2. Distribution and Room Air Mixing Risks to Retrofitted Homes

    Energy Technology Data Exchange (ETDEWEB)

    Burdick, A. [IBACOS, Inc., Pittsburgh, PA (United States)

    2014-12-01

    Energy efficiency upgrades reduce heating and cooling loads on a house. With enough load reduction and if the HVAC system warrants replacement, the HVAC system is often upgraded with a more efficient, lower capacity system that meets the loads of the upgraded house. For a single-story house with ceiling supply air diffusers, ducts are often removed and upgraded. For houses with ducts that are embedded in walls, the cost of demolition precludes the replacement of ducts. The challenge with the use of existing ducts is that the reduced airflow creates a decreased throw at the supply registers, and the supply air and room air do not mix well, leading to potential thermal comfort complaints. This project investigates this retrofit scenario. The issues and solutions discussed here are relevant to all climate zones, with emphasis on climates that require cooling.

  3. Aerosol distribution measurements by laser - Doppler - spectroscopy

    International Nuclear Information System (INIS)

    Baldassari, J.

    1977-01-01

    Laser-Doppler-Spectroscopy is used to study particle size distribution, especially sodium aerosols, in the presence of uncondensable gases. Theoretical basis are given, and an experimental technique is described. First theoretical results show reasonably good agreement with experimental data available; this method seems to be a promising one. (author)

  4. Device for improved air and fuel distribution to a combustor

    Science.gov (United States)

    Laster, Walter R.; Schilp, Reinhard

    2016-05-31

    A flow conditioning device (30, 50, 70, 100, 150) for a can annular gas turbine engine, including a plurality of flow elements (32, 34, 52, 54, 72, 74, 102) disposed in a compressed air flow path (42, 60, 80, 114, 122) leading to a combustor (12), configured such that relative adjustment of at least one flow directing element (32, 52, 72, 110) with respect to an adjacent flow directing element (34, 54, 74, 112, 120) during operation of the gas turbine engine is effective to adjust a level of choking of the compressed air flow path (42, 60, 80, 114, 122).

  5. Air Distribution in a Furnished Room Ventilated by Mixing Ventilation

    DEFF Research Database (Denmark)

    Nielsen, June Richter; Nielsen, Peter V.; Svidt, Kjeld

    Using isothermal full-scale experiments and two-dimensional isothermal CFD simulations it is investigated how normal office furniture influences the air movements in a room with mixing ventilation. Three different set-ups are made in the experiments and different sizes and locations of the furnit......Using isothermal full-scale experiments and two-dimensional isothermal CFD simulations it is investigated how normal office furniture influences the air movements in a room with mixing ventilation. Three different set-ups are made in the experiments and different sizes and locations...

  6. Disruptive Innovation in Air Measurement Technology: Reality or Hype?

    Science.gov (United States)

    This presentation is a big picture overview on the changing state of air measurement technology in the world, with a focus on the introduction of low-cost sensors into the market place. The presentation discusses how these new technologies may be a case study in disruptive innov...

  7. Objective Measure of Nasal Air Emission Using Nasal Accelerometry

    Science.gov (United States)

    Cler, Meredith J.; Lien, Yu-An, S.; Braden, Maia N.; Mittleman, Talia; Downing, Kerri; Stepp, Cara, E.

    2016-01-01

    Purpose: This article describes the development and initial validation of an objective measure of nasal air emission (NAE) using nasal accelerometry. Method: Nasal acceleration and nasal airflow signals were simultaneously recorded while an expert speech language pathologist modeled NAEs at a variety of severity levels. In addition, microphone and…

  8. In-situ measurements in Vesivehmaa air field - STUK team

    Energy Technology Data Exchange (ETDEWEB)

    Markkanen, M.; Honkamaa, T.; Niskala, P. [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland)

    1997-12-31

    Nineteen in-situ gamma-ray spectrometric measurements were performed in Vesivehmaa air field on 17th August 1995. The results for {sup 137}Cs and natural radionuclides are in good agreement with the results from soil sampling and laboratory analyses. (au).

  9. Three phase voltage measurements with simple open air sensors

    NARCIS (Netherlands)

    Heesch, van E.J.M.; Caspers, R.; Gulickx, P.F.M.; Jacobs, G.A.P.; Kersten, W.F.J.; Laan, van der P.C.T.

    1991-01-01

    A low cost, easy to install high-voltage measuring system is described for open air substations and overhead lines. Based on the Differentiating/Integrating (D/I) principle, three free-standing capacitive pickup electrodes are used to sense the three phase to ground voltages. Apart from the

  10. In-situ measurements in Vesivehmaa air field - STUK team

    Energy Technology Data Exchange (ETDEWEB)

    Markkanen, M; Honkamaa, T; Niskala, P [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland)

    1998-12-31

    Nineteen in-situ gamma-ray spectrometric measurements were performed in Vesivehmaa air field on 17th August 1995. The results for {sup 137}Cs and natural radionuclides are in good agreement with the results from soil sampling and laboratory analyses. (au).

  11. Reliability and Inequality Measures for the Weimal Distribution ...

    African Journals Online (AJOL)

    ). This article aimed at discussing both reliability and inequality measures from the Weimal distribution. The work has derived and discussed theoretically, expressions for the survival and hazard function of the Weimal distribution. The ordinary ...

  12. Measurement of Ambient Air Particle (TSP, PM10, PM2,5) Around Candidate Location of PLTN Semenanjung Lemahabang

    International Nuclear Information System (INIS)

    AgusGindo S; Budi Hari H

    2008-01-01

    Measurement analysis of ambient air particle (TSP, PM 10 , PM 2,5 ) around location candidate of PLTN (Power Station of Nuclear Energy) Semenanjung Lemahabang has been carried out. The measurement was conducted in May 2007 with a purpose to providing information about concentration of ambient air particle (TSP, PM 10 , PM 2,5 ) and diameter distribution of its air particle. The measurement was conducted in three locations i.e. 1). Balong village 2). Bayuran 3). Bondo. Concentration of TSP, PM 10 , and PM 2,5 per 24 hours in all measured locations in area candidate of PLTN exceed quality standard of national ambient air is specified by government. All measurement locations for the TSP, PM 10 , and PM 2,5 was include category of ISPU (Standard Index of Air Pollution) moderate. (author)

  13. Applications of synergistic combination of remote sensing and in-situ measurements on urban monitoring of air quality

    Science.gov (United States)

    Diaz, Adrian; Dominguez, Victor; Campmier, Mark; Wu, Yonghua; Arend, Mark; Vladutescu, Daniela Viviana; Gross, Barry; Moshary, Fred

    2017-08-01

    In this study, multiple remote sensing and in-situ measurements are combined in order to obtain a comprehensive understanding of the aerosol distribution in New York City. Measurement of the horizontal distribution of aerosols is performed using a scanning eye-safe elastic-backscatter micro-pulse lidar. Vertical distribution of aerosols is measured with a co-located ceilometer. Furthermore, our analysis also includes in-situ measurements of particulate matter and wind speed and direction. These observations combined show boundary layer dynamics as well as transport and inhomogeneous spatial distribution of aerosols, which are of importance for air quality monitoring.

  14. Distributed Measurement Data Gathering about Moving Objects

    Directory of Open Access Journals (Sweden)

    Ivan Kholod

    2017-01-01

    Full Text Available This paper describes approaches to gathering measurement data about moving objects in networks with low bandwidth. The first approach uses Fog computing conception and suggests moving assessing the quality of the measurement data into measuring points. The second approach uses prediction of telemetry quality by mining models. In addition, the paper presents implementation of these approaches based on actor model. As a result, it became possible not only to load balancing among edge and cloud nodes, but also to significantly reduce the network traffic, which in turn brings the possibility of decreasing the requirements for communication channels bandwidth and of using wireless networks for gathering measurement data about moving objects.

  15. Optimisation of key performance measures in air cargo demand management

    OpenAIRE

    Alexander May; Adrian Anslow; Udechukwu Ojiako; Yue Wu; Alasdair Marshall; Maxwell Chipulu

    2014-01-01

    This article sought to facilitate the optimisation of key performance measures utilised for demand management in air cargo operations. The focus was on the Revenue Management team at Virgin Atlantic Cargo and a fuzzy group decision-making method was used. Utilising intelligent fuzzy multi-criteria methods, the authors generated a ranking order of ten key outcome-based performance indicators for Virgin Atlantic air cargo Revenue Management. The result of this industry-driven study showed that ...

  16. The effects of mixing air distribution and heat load arrangement on the performance of ceiling radiant panels under cooling mode of operation

    DEFF Research Database (Denmark)

    Mustakallio, Panu; Kosonen, Risto; Melikov, Arsen Krikor

    2016-01-01

    arrangement and air distribution generated in a room by linear slot diffuser, radial multi-nozzle diffuser and radial swirl induction unit on the cooling power of radiant panels was compared. The impact on the thermal environment was also studied. Measurements were carried out without and with supply air...

  17. 1991 measurement report. Air pollution monitoring in Schleswig-Holstein

    International Nuclear Information System (INIS)

    1992-01-01

    This article provides a report of the immission situation for 1991 in Schleswig-Holstein on the basis of the continuously processing measuring stations of the Air Hygienic Monitoring Schleswig-Holstein and the special measuring programs at selected sites. The measuring results of the Air Hygienic Monitoring determined for Schleswig-Holstein in 1991 can be summarized as follows: - The basic load of air by pollutants such as sulphur dioxide (SO 2 ), nitrogen monoxide (NO), nitrogen dioxide (NO 2 ) and airborne particles in relatively small in the entires region of the nation; Schleswig-Holstein is, therefore, continues to be ranked as one of the regions in the Federal Republic of Germany least burden to air contaminates. - A slight increase compared to the previous year could be determined for the components of sulphur dioxide and airborne particles. - The limit values defined by the European Community (EG) were adhered to at the time of the report; the admittance values for SO 2 and NO 2 were, however, exceeded. (orig./KW) [de

  18. A Distributed Simulation Facility to Support Human Factors Research in Advanced Air Transportation Technology

    Science.gov (United States)

    Amonlirdviman, Keith; Farley, Todd C.; Hansman, R. John, Jr.; Ladik, John F.; Sherer, Dana Z.

    1998-01-01

    A distributed real-time simulation of the civil air traffic environment developed to support human factors research in advanced air transportation technology is presented. The distributed environment is based on a custom simulation architecture designed for simplicity and flexibility in human experiments. Standard Internet protocols are used to create the distributed environment, linking all advanced cockpit simulator, all Air Traffic Control simulator, and a pseudo-aircraft control and simulation management station. The pseudo-aircraft control station also functions as a scenario design tool for coordinating human factors experiments. This station incorporates a pseudo-pilot interface designed to reduce workload for human operators piloting multiple aircraft simultaneously in real time. The application of this distributed simulation facility to support a study of the effect of shared information (via air-ground datalink) on pilot/controller shared situation awareness and re-route negotiation is also presented.

  19. Design of air distribution system in operating rooms -theory versus practice

    NARCIS (Netherlands)

    Melhado, M.A.; Loomans, M.G.L.C.; Hensen, J.L.M.; Lamberts, R.

    2016-01-01

    Air distribution systems need to secure a good indoor air quality in operating rooms (ORs), minimize the risk of surgical site infections, and establish suitable working conditions for the surgical team through the thermal comfort. The paper presents an overview of the design and decision process of

  20. Towards a performance assessment methodology using computational simulation for air distribution system designs in operating rooms

    NARCIS (Netherlands)

    Melhado, M.D.A.

    2012-01-01

    One of the important performance requirements for an air distribution system for an operating room (OR) is to provide good indoor environmental conditions in which to perform operations. Important conditions in this respect relate to the air quality and to the thermal conditions for the surgical

  1. Measurements of air entrainment by vertical plunging liquid jets

    Science.gov (United States)

    El Hammoumi, M.; Achard, J. L.; Davoust, L.

    2002-06-01

    This paper addresses the issue of the air-entrainment process by a vertical plunging liquid jet. A non-dimensional physical analysis, inspired by the literature on the stability of free jets submitted to an aerodynamic interaction, was developed and yielded two correlation equations for the laminar and the turbulent plunging jets. These correlation equations allow the volumetric flow rate of the air carryunder represented by the Weber number of entrainment We n to be predicted. The plunging jets under consideration issued from circular tubes long enough to achieve a fully developed flow at the outlet. A sensitive technique based on a rising soap meniscus was developed to measure directly the volumetric flow rate of the air carryunder. Our data are compared with other experimental data available in the literature; they also stand as a possible database for future theoretical modelling.

  2. Measurements of air entrainment by vertical plunging liquid jets

    Energy Technology Data Exchange (ETDEWEB)

    El Hammoumi, M. [Faculte des Sciences et Techniques, Departement de Physique, Laboratoire de Mecanique Appliquee, Fes (Morocco); Achard, J.L.; Davoust, L. [Laboratoire des Ecoulements Geophysiques et Industriels (LEGI), Grenoble (France)

    2002-06-01

    This paper addresses the issue of the air-entrainment process by a vertical plunging liquid jet. A non-dimensional physical analysis, inspired by the literature on the stability of free jets submitted to an aerodynamic interaction, was developed and yielded two correlation equations for the laminar and the turbulent plunging jets. These correlation equations allow the volumetric flow rate of the air carryunder represented by the Weber number of entrainment We{sub n} to be predicted. The plunging jets under consideration issued from circular tubes long enough to achieve a fully developed flow at the outlet. A sensitive technique based on a rising soap meniscus was developed to measure directly the volumetric flow rate of the air carryunder. Our data are compared with other experimental data available in the literature; they also stand as a possible database for future theoretical modelling. (orig.)

  3. Method and device for measuring the smoke concentration in air

    International Nuclear Information System (INIS)

    Rennemo, B.

    1994-01-01

    The patent deals with a method and a device for measuring the smoke concentration in air. In a smoke chamber are located two electrodes, connected to a voltage source for forming a circuit in which a DC current flows. A radioactive radiation source to ionize the air molecules is located in the vicinity of the smoke chamber, so that the number of ionized air molecules which are formed is dependent upon the radiation intensity of the ion source and the concentration of smoke particles in the smoke chamber. The charging voltage will further imply that a cloud of high ion concentration is built up close to the surface of the electrodes. The ion cloud will be discharged capacitively upon a plurality of short voltages pulses applied to the electrodes to thereby result in current pulses substantially greater than the DC current flowing through the chamber. 8 figs

  4. Flux distribution measurements in the Bruce A unit 1 reactor

    International Nuclear Information System (INIS)

    Okazaki, A.; Kettner, D.A.; Mohindra, V.K.

    1977-07-01

    Flux distribution measurements were made by copper wire activation during low power commissioning of the unit 1 reactor of the Bruce A generating station. The distribution was measured along one diameter near the axial and horizontal midplanes of the reactor core. The activity distribution along the copper wire was measured by wire scanners with NaI detectors. The experiments were made for five configurations of reactivity control mechanisms. (author)

  5. Measuring Distribution Performance? Benchmarking Warrants Your Attention

    Energy Technology Data Exchange (ETDEWEB)

    Ericson, Sean J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Alvarez, Paul [The Wired Group

    2018-04-13

    Identifying, designing, and measuring performance metrics is critical to securing customer value, but can be a difficult task. This article examines the use of benchmarks based on publicly available performance data to set challenging, yet fair, metrics and targets.

  6. Intercomparison of different instruments for measuring radon concentration in air

    International Nuclear Information System (INIS)

    Shimo, Michikuni; Iida, Takao

    1990-01-01

    An intercomparison of different instruments for measurement of radon concentration was carried out. The instruments include an ionization chamber, the charcoal-trap method, a flow-type ionization chamber (pulse-counting method), a two-filter method, an electrostatic collection method and a passive integration radon monitor. All instruments except for the passive radon monitor have been calibrated independently. Measurements were performed over a concentration range from about 3.5 Bq·m -3 (in outdoor air) to 110 Bq·m -3 (in indoor air). The results obtained by these techniques, except the two-filter technique, are comparable. Radon daughter concentration measured using a filter-sampling method was about 52% of radon concentration. (author)

  7. Intercomparison of different instruments that measure radon concentration in air

    International Nuclear Information System (INIS)

    Shimo, M.; Iida, T.; Ikebe, Y.

    1987-01-01

    An intercomparison of different instruments for measurement of radon concentration was carried out. The instruments include an ionization chamber, the charcoal-trap technique, a flow-type ionization chamber (pulse-counting technique), a two-filter method, an electrostatic collection method and a passive integrating radon monitor. All instruments except for the passive radon monitor have been calibrated independently. Measurements were performed over a concentration range from about 3.5 Bq/m/sup 3/ (in outdoor air) to 110 Bq/m/sup 3/ (in indoor air). The results obtained from these techniques, except the two-filter technique, are comparable. Radon daughter concentration measured using a filter-sampling technique was about 52% of radon concentrations

  8. Measurement of air pollutant emissions from Lome, Cotonou and Accra

    Science.gov (United States)

    Lee, James; Vaughan, Adam; Nelson, Bethany; Young, Stuart; Evans, Mathew; Morris, Eleanor; Ladkin, Russel

    2017-04-01

    High concentrations of airborne pollutants (e.g. the oxides of nitrogen, sulphur dioxide and carbon monoxide) in existing and evolving cities along the Guinea Coast cause respiratory diseases with potentially large costs to human health and the economic capacity of the local workforce. It is important to understand the rate of emission of such pollutants in order to model current and future air quality and provide guidance to the potential outcomes of air pollution abatement strategies. Often dated technologies and poor emission control strategies lead to substantial uncertainties in emission estimates calculated from vehicle and population number density statistics. The unreliable electrical supply in cities in the area has led to an increased reliance on small-scale diesel powered generators and these potentially present a significant source of emissions. The uncontrolled open incineration of waste adds a further very poorly constrained emission source within the cities. The DACCIWA (Dynamics-Aerosol-Chemistry-Cloud Interactions in West Africa) project involved a field campaign which used highly instrumented aircraft capable of in situ measurements of a range of air pollutants. Seven flights using the UK British Antarctic Survey's Twin Otter aircraft specifically targeted air pollution emissions from cities in West Africa (4 x Accra, Ghana; 2 x Lome, Togo and 1 x Cotonou, Benin). Measurements of NO, NO2, SO2, CO, CH4 and CO2 were made at multiple altitudes upwind and downwind of the cities, with the mass balance technique used to calculate emission rates. These are then compared to the Emissions Database for Global Atmospheric Research (EDGAR) estimates. Ultimately the data will be used to inform on and potentially improve the emission estimates, which in turn should lead to better forecasting of air pollution in West African cities and help guide future air pollution abatement strategy.

  9. Determining air distribution during outbursts of gases and rocks

    Energy Technology Data Exchange (ETDEWEB)

    Struminski, A; Sikora, M; Urbanski, J [Politechnika Wroclawska (Poland). Instytut Gornictwa

    1989-01-01

    Discusses use of the KPW-1 iterative and autocorrelation method developed by A. Struminski for forecasting effects of rock bursts on ventilation systems of underground coal mines with increased content of methane or carbon dioxide in coal seams and adjacent rock strata. The method is used for prediction of air flow changes caused by a rock burst accompanied by violent outburst of gases. Directions of air flow, flow rate and concentration of gases emitted from surrounding strata to mine workings are predicted. On the basis of this prediction concentration of gases from a coal outburst is determined for any point in a ventilation network. The prediction method is used for assessing hazards for coal mines during and after a rock burst. Use of the method is explained on the example of the Thorez and Walbrzych coal mines. Computer programs developed for ODRA and IBM/XT computers are discussed. 6 refs.

  10. Air slab-correction for Γ-ray attenuation measurements

    Science.gov (United States)

    Mann, Kulwinder Singh

    2017-12-01

    Gamma (γ)-ray shielding behaviour (GSB) of a material can be ascertained from its linear attenuation coefficient (μ, cm-1). Narrow-beam transmission geometry is required for μ-measurement. In such measurements, a thin slab of the material has to insert between point-isotropic γ-ray source and detector assembly. The accuracy in measurements requires that sample's optical thickness (OT) remain below 0.5 mean free path (mfp). Sometimes it is very difficult to produce thin slab of sample (absorber), on the other hand for thick absorber, i.e. OT >0.5 mfp, the influence of the air displaced by it cannot be ignored during μ-measurements. Thus, for a thick sample, correction factor has been suggested which compensates the air present in the transmission geometry. The correction factor has been named as an air slab-correction (ASC). Six samples of low-Z engineering materials (cement-black, clay, red-mud, lime-stone, cement-white and plaster-of-paris) have been selected for investigating the effect of ASC on μ-measurements at three γ-ray energies (661.66, 1173.24, 1332.50 keV). The measurements have been made using point-isotropic γ-ray sources (Cs-137 and Co-60), NaI(Tl) detector and multi-channel-analyser coupled with a personal computer. Theoretical values of μ have been computed using a GRIC2-toolkit (standardized computer programme). Elemental compositions of the samples were measured with Wavelength Dispersive X-ray Fluorescence (WDXRF) analyser. Inter-comparison of measured and computed μ-values, suggested that the application of ASC helps in precise μ-measurement for thick samples of low-Z materials. Thus, this hitherto widely ignored ASC factor is recommended to use in similar γ-ray measurements.

  11. Asessing the air pollution distribution in busy street of Copenhagen in the further development of a street pollution model

    DEFF Research Database (Denmark)

    Hertel, Ole; Ketzel, Matthias; Poulsen, Maria B.

    The EU Air Quality Directive requires Member States to perform Air Quality Monitoring in order to assess ambient air quality for compliance checking with air quality limit values (http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2008:152:0001:0044:en:PDF). This monitoring needs to include......) developed at AU; the revised version OSPM includes new features like inhomogeneous distribution of the traffic on different lanes, slope of the street etc (see e.g. Ottosen et al. (2015)). An additional goal for the project is to explore the applicability of low-cost electrochemical sensors for describing...... to get more detailed information about the traffic flow and its diurnal pattern, manual traffic counts have been performed over 24 hours. In addition a video camera has been installed on the roof of a building next to the street during the monitoring campaign. Measurements are carried out using passive...

  12. Air quality impacts of distributed power generation in the South Coast Air Basin of California 1: Scenario development and modeling analysis

    Science.gov (United States)

    Rodriguez, M. A.; Carreras-Sospedra, M.; Medrano, M.; Brouwer, J.; Samuelsen, G. S.; Dabdub, D.

    Distributed generation (DG) is generally defined as the operation of many small stationary power generators throughout an urban air basin. Although DG has the potential to supply a significant portion of the increased power demands in California and the rest of the United States, it may lead to increased levels of in-basin pollutants and adversely impact urban air quality. This study focuses on two main objectives: (1) the systematic characterization of DG installation in urban air basins, and (2) the simulation of potential air quality impacts using a state-of-the-art three-dimensional computational model. A general and systematic approach is devised to construct five realistic and 21 spanning scenarios of DG implementation in the South Coast Air Basin (SoCAB) of California. Realistic scenarios reflect an anticipated level of DG deployment in the SoCAB by the year 2010. Spanning scenarios are developed to determine the potential impacts of unexpected outcomes. Realistic implementations of DG in the SoCAB result in small differences in ozone and particulate matter concentrations in the basin compared to the baseline simulations. The baseline accounts for population increase, but does not consider any future emissions control measures. Model results for spanning implementations with extra high DG market penetration show that domain-wide ozone peak concentrations increase significantly. Also, air quality impacts of spanning implementations when DG operate during a 6-h period are larger than when the same amount of emissions are introduced during a 24-h period.

  13. Intraoperative air leak measured after lobectomy is associated with postoperative duration of air leak.

    Science.gov (United States)

    Brunelli, Alessandro; Salati, Michele; Pompili, Cecilia; Gentili, Paolo; Sabbatini, Armando

    2017-11-01

    To verify the association between the air leak objectively measured intraoperatively (IAL) using the ventilator and the air leak duration after pulmonary lobectomy. Prospective analysis on 111 patients submitted to pulmonary lobectomy (33 by video-assisted thoracic surgery). After resection, objective assessment of air leak (in milliliter per minute) was performed before closure of the chest by measuring the difference between a fixed inspired and expired volume, using a tidal volume of 8 ml/kg, a respiratory rate of 10 and a positive-end expiratory pressure of 5 cmH2O. A multivariable analysis was performed for identifying factors associated with duration of postoperative air leak. Average IAL was 158 ml/min (range 0-1500 ml/min). The best cut-off (receiver-operating characteristics analysis) associated with air leak longer than 5 days was 500 ml/min. Nine patients had IAL >500 ml/min (8%). They had a longer duration of postoperative air leak compared with those with a lower IAL (mean values, 10.1 days, SD 8.8 vs 1.5 days, SD 4.9 P leak duration after multivariable regression: left side resection (P = 0.018), upper site resection (P = 0.031) and IAL >500 ml/min (P leak duration was generated: 1.7 + 2.4 × left side + 2.2 × upper site + 8.8 × IAL >500. The air leak measurement using the ventilator parameters after lung resection may assist in estimating the risk of postoperative prolonged air leak. An IAL > 500 ml/min may warrant the use of intraoperative preventative measures, particularly after video-assisted thoracic surgery lobectomy where a submersion test is often unreliable. © 2017 European Society of Cardiology and European Atherosclerosis Association. All rights reserved. For permissions please email: journals.permissions@oup.com.

  14. Multi-objective optimization design of air distribution of grate cooler by entropy generation minimization and genetic algorithm

    International Nuclear Information System (INIS)

    Shao, Wei; Cui, Zheng; Cheng, Lin

    2016-01-01

    Highlights: • A multi-objective optimization model of air distribution of grate cooler by genetic algorithm is proposed. • Pareto Front is obtained and validated by comparing with operating data. • Optimal schemes are compared and selected by engineering background. • Total power consumption after optimization decreases 61.10%. • Thickness of clinker on three grate plates is thinner. - Abstract: The cooling air distributions of grate cooler exercise a great influence on the clinker cooling efficiency and power consumption of cooling fans. A multi-objective optimization model of air distributions of grate cooler with cross-flow heat exchanger analogy is proposed in this paper. Firstly, thermodynamic and flow models of clinker cooling process is carried out. Then based on entropy generation minimization analysis, modified entropy generation numbers caused by heat transfer and pressure drop are chosen as objective functions respectively which optimized by genetic algorithm. The design variables are superficial velocities of air chambers and thicknesses of clinker layers on different grate plates. A set of Pareto optimal solutions which two objectives are optimized simultaneously is achieved. Scattered distributions of design variables resulting in the conflict between two objectives are brought out. The final optimal air distribution and thicknesses of clinker layers are selected from the Pareto optimal solutions based on power consumption of cooling fans minimization and validated by measurements. Compared with actual operating scheme, the total air volumes of optimized schemes decrease 2.4%, total power consumption of cooling fans decreases 61.1% and the outlet temperature of clinker decreases 122.9 °C which shows a remarkable energy-saving effect on energy consumption.

  15. Measurements of acetylene in air extracted from polar ice cores

    Science.gov (United States)

    Nicewonger, M. R.; Aydin, M.; Montzka, S. A.; Saltzman, E. S.

    2016-12-01

    Acetylene (ethyne) is a non-methane hydrocarbon emitted during combustion of fossil fuels, biofuels, and biomass. The major atmospheric loss pathway of acetylene is oxidation by hydroxyl radical with a lifetime estimated at roughly two weeks. The mean annual acetylene levels over Greenland and Antarctica are 250 ppt and 20 ppt, respectively. Firn air measurements suggest atmospheric acetylene is preserved unaltered in polar snow and firn. Atmospheric reconstructions based on firn air measurements indicate acetylene levels rose significantly during the twentieth century, peaked near 1980, then declined to modern day levels. This historical trend is similar to that of other fossil fuel-derived non-methane hydrocarbons. In the preindustrial atmosphere, acetylene levels should primarily reflect emissions from biomass burning. In this study, we present the first measurements of acetylene in preindustrial air extracted from polar ice cores. Air from fluid and dry-drilled ice cores from Summit, Greenland and WAIS-Divide Antarctica is extracted using a wet-extraction technique. The ice core air is analyzed using gas chromatography and high-resolution mass spectrometry. Between 1400 to 1800 C.E., acetylene levels over Greenland and Antarctica varied between roughly 70-120 ppt and 10-30 ppt, respectively. The preindustrial Greenland acetylene levels are significantly lower than modern levels, reflecting the importance of northern hemisphere fossil fuel sources today. The preindustrial Antarctic acetylene levels are comparable to modern day levels, indicating similar emissions in the preindustrial atmosphere, likely from biomass burning. The implications of the preindustrial atmospheric acetylene records from both hemispheres will be discussed.

  16. Measurements of radon activity concentrations in air at Niska spa

    International Nuclear Information System (INIS)

    Adrovic, F.; Vuckovic, B.; Ninkovic, M.

    2004-01-01

    Radon activity concentrations in air were measured in the recreational-tourist center of Niska Banja. Alpha Guard PQ 2000/ MC50 instrumentation (Genitron instruments, Frankfurt) was used. The observed indoor radon concentrations in the air of the Radon Hotel pool lay within the range of 0.980-1.908 kBq/m 3 and were directly dependent on the exhalation of radon from thermomineral waters. Radon concentrations were also measured outdoors, at locations for capping thermomineral water, as well as at locations for draining used water from the Radon Hotel pool. Outdoor radon concentrations as high as over 500 Bq/m 3 were observed. Gamma dose rates were measured in parallel and found to lie within the range of 72-420 nSv/h. The gamma doses correlated well with the observed radon levels. The largest gamma dose rates in air were measured in the pool of Radon Hotel and at the site where this thermomineral water is being capped

  17. An Air Bearing Rotating Coil Magnetic Measurement System

    CERN Document Server

    Gottschalk, Stephen C; Taylor, David J; Thayer, William

    2005-01-01

    This paper describes a rotating coil magnetic measurement system supported on air bearings. The design is optimized for measurements of 0.1micron magnetic centerline changes on long, small aperture quadrupoles. Graphite impregnated epoxy resin is used for the coil holder and coil winding forms. Coil holder diameter is 11 mm with a length between supports of 750mm. A pair of coils is used to permit quadrupole bucking during centerline measurements. Coil length is 616mm, inner radius 1.82mm, outer radius 4.74mm. The key features of the mechanical system are simplicity; air bearings for accurate, repeatable measurements without needing warm up time and a vibration isolated stand that uses a steel-topped Newport optical table with air suspension. Coil rotation is achieved by a low noise servo motor controlled by a standalone Ethernet servo board running custom servo software. Coil calibration procedures that correct wire placement errors, tests for mechanical resonances, and other system checks will also be discu...

  18. Air-mass flux measurement system using Doppler-shifted filtered Rayleigh scattering

    Science.gov (United States)

    Shirley, John A.; Winter, Michael

    1993-01-01

    An optical system has been investigated to measure mass flux distributions in the inlet of a high speed air-breathing propulsion system. Rayleigh scattered light from air is proportional to the number density of molecules and hence can be used to ascertain the gas density in a calibrated system. Velocity field measurements are achieved by spectrally filtering the elastically-scattered Doppler-shifted light with an absorbing molecular filter. A novel anamorphic optical collection system is used which allows optical rays from different scattering angles, that have different Doppler shifts, to be recorded separately. This is shown to obviate the need to tune the laser through the absorption to determine velocities, while retaining the ability to make spatially-resolved measurements along a line. By properly selecting the laser tuning and filter parameters, simultaneous density measurements can be made. These properties are discussed in the paper and experiments demonstrating the velocimetry capability are described.

  19. Measurement of acetates in air using differential ion mobility spectrometer

    Science.gov (United States)

    Szczurek, Andrzej; Maciejewska, Monika; Zajiczek, Żaneta; Maziejuk, Mirosław

    2017-11-01

    Volatile organic compounds are one of the most important group of air pollutants. Potential health and environmental problems resulting from their emission prompted the requirement for monitoring these species. It motivates development of new measurement techniques which are fast, cost effective, reliable and field deployable. One of novel approaches is ion mobility spectrometry. It dwells on ion separation in electric field, based on differences in ion mobility. Many variants of this method are developed. In this wok, differential ion mobility spectrometry (DMS) was considered in respect of acetate measurements in air. It was demonstrated that DMS offers linear response to methyl, ethyl, propyl and butyl acetate in concentration range from 0.3 ppm to 7 ppm. Positive ions spectrum has to be utilised for this purpose. We showed that fragments of DMS spectrum which secure linearity are compound-specific. The obtained results are promising from the application point of view.

  20. 40 CFR 86.313-79 - Air flow measurement specifications; diesel engines.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Air flow measurement specifications... Procedures § 86.313-79 Air flow measurement specifications; diesel engines. (a) The air flow measurement... (CONTINUED) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES...

  1. Effect of Smart Meter Measurements Data On Distribution State Estimation

    DEFF Research Database (Denmark)

    Pokhrel, Basanta Raj; Nainar, Karthikeyan; Bak-Jensen, Birgitte

    2018-01-01

    Smart distribution grids with renewable energy based generators and demand response resources (DRR) requires accurate state estimators for real time control. Distribution grid state estimators are normally based on accumulated smart meter measurements. However, increase of measurements in the phy......Smart distribution grids with renewable energy based generators and demand response resources (DRR) requires accurate state estimators for real time control. Distribution grid state estimators are normally based on accumulated smart meter measurements. However, increase of measurements...... in the physical grid can enforce significant stress not only on the communication infrastructure but also in the control algorithms. This paper aims to propose a methodology to analyze needed real time smart meter data from low voltage distribution grids and their applicability in distribution state estimation...

  2. Measurement of subcritical multiplication by the interval distribution method

    International Nuclear Information System (INIS)

    Nelson, G.W.

    1985-01-01

    The prompt decay constant or the subcritical neutron multiplication may be determined by measuring the distribution of the time intervals between successive neutron counts. The distribution data is analyzed by least-squares fitting to a theoretical distribution function derived from a point reactor probability model. Published results of measurements with one- and two-detector systems are discussed. Data collection times are shorter, and statistical errors are smaller the nearer the system is to delayed critical. Several of the measurements indicate that a shorter data collection time and higher accuracy are possible with the interval distribution method than with the Feynman variance method

  3. Measurement of horizontal air showers with the Auger Engineering Radio Array

    Science.gov (United States)

    Kambeitz, Olga

    2017-03-01

    The Auger Engineering Radio Array (AERA), at the Pierre Auger Observatory in Argentina, measures the radio emission of extensive air showers in the 30-80 MHz frequency range. AERA consists of more than 150 antenna stations distributed over 17 km2. Together with the Auger surface detector, the fluorescence detector and the underground muon detector (AMIGA), AERA is able to measure cosmic rays with energies above 1017 eV in a hybrid detection mode. AERA is optimized for the detection of air showers up to 60° zenith angle, however, using the reconstruction of horizontal air showers with the Auger surface array, very inclined showers can also be measured. In this contribution an analysis of the AERA data in the zenith angle range from 62° to 80° will be presented. CoREAS simulations predict radio emission footprints of several km2 for horizontal air showers, which are now confirmed by AERA measurements. This can lead to radio-based composition measurements and energy determination of horizontal showers in the future and the radio detection of neutrino induced showers is possible.

  4. Measures related to traffic planning for air pollution control

    Energy Technology Data Exchange (ETDEWEB)

    Baumueller, J; Reuter, U [Office of Environmental Protection, Stuttgart (Germany). Dept. for Climatology

    1996-12-31

    The immense increase of motor traffic, in the future reinforced by the European market and the opening of boarders to the east countries, requires new efforts in traffic policy. In the city agglomerations the motor traffic is nearly collapsing. The increase of motor traffic is the reason for a considerable degradation of environment, especially by noise and air pollution. For the region of Stuttgart the problems and possibilities of counter-measures are discussed. (author)

  5. Measures related to traffic planning for air pollution control

    Energy Technology Data Exchange (ETDEWEB)

    Baumueller, J.; Reuter, U. [Office of Environmental Protection, Stuttgart (Germany). Dept. for Climatology

    1995-12-31

    The immense increase of motor traffic, in the future reinforced by the European market and the opening of boarders to the east countries, requires new efforts in traffic policy. In the city agglomerations the motor traffic is nearly collapsing. The increase of motor traffic is the reason for a considerable degradation of environment, especially by noise and air pollution. For the region of Stuttgart the problems and possibilities of counter-measures are discussed. (author)

  6. Measuring the speed of sound in air using smartphone applications

    Science.gov (United States)

    Yavuz, A.

    2015-05-01

    This study presents a revised version of an old experiment available in many textbooks for measuring the speed of sound in air. A signal-generator application in a smartphone is used to produce the desired sound frequency. Nodes of sound waves in a glass pipe, of which one end is immersed in water, are more easily detected, so results can be obtained more quickly than from traditional acoustic experiments using tuning forks.

  7. Measuring the muon content of air showers with IceTop

    Science.gov (United States)

    Gonzalez, Javier G.

    2015-08-01

    IceTop, the surface component of the IceCube detector, has been used to measure the energy spectrum of cosmic ray primaries in the range between 1.58 PeV and 1.26 EeV. It can also be used to study the low energy muons in air showers by looking at large distances (> 300 m) from the shower axis. We will show the muon lateral distribution function at large lateral distances as measured with IceTop and discuss the implications of this measurement. We will also discuss the prospects for low energy muon studies with IceTop.

  8. Measuring the muon content of air showers with IceTop

    Directory of Open Access Journals (Sweden)

    Gonzalez Javier G.

    2015-01-01

    Full Text Available IceTop, the surface component of the IceCube detector, has been used to measure the energy spectrum of cosmic ray primaries in the range between 1.58 PeV and 1.26 EeV. It can also be used to study the low energy muons in air showers by looking at large distances (> 300 m from the shower axis. We will show the muon lateral distribution function at large lateral distances as measured with IceTop and discuss the implications of this measurement. We will also discuss the prospects for low energy muon studies with IceTop.

  9. Determination of air movement in stored grain as a factor in dynamic dispersion and distribution patterns of gaseous pesticides (fumigants).

    Science.gov (United States)

    Berck, B

    1975-05-01

    The new research reported herein was motivated by variations in distribution-persistence patterns of fumigant residues (BERCK, 1974). The current developmental program is still underway. In the meantime, measurement of picoliter amounts of SF6 in air by GC equipped with a Ni63 EC detector has been proven useful over an airflow range of 10(-4) to 50 mph, representing a factor of 500,000 in differences in air velocity. Diverse applications have been outlined herein. This is the first case on record where measurement of unassisted airflow in the interstitial air of stored grain has been successfully executed, and which enabled determination of airflow speeds in the range of 0.5 to 7.5 times 10(-4) mph (=3 to 45 inches per hour).

  10. Speciated arsenic in air: measurement methodology and risk assessment considerations.

    Science.gov (United States)

    Lewis, Ari S; Reid, Kim R; Pollock, Margaret C; Campleman, Sharan L

    2012-01-01

    Accurate measurement of arsenic (As) in air is critical to providing a more robust understanding of arsenic exposures and associated human health risks. Although there is extensive information available on total arsenic in air, less is known on the relative contribution of each arsenic species. To address this data gap, the authors conducted an in-depth review of available information on speciated arsenic in air. The evaluation included the type of species measured and the relative abundance, as well as an analysis of the limitations of current analytical methods. Despite inherent differences in the procedures, most techniques effectively separated arsenic species in the air samples. Common analytical techniques such as inductively coupled plasma mass spectrometry (ICP-MS) and/or hydride generation (HG)- or quartz furnace (GF)-atomic absorption spectrometry (AAS) were used for arsenic measurement in the extracts, and provided some of the most sensitive detection limits. The current analysis demonstrated that, despite limited comparability among studies due to differences in seasonal factors, study duration, sample collection methods, and analytical methods, research conducted to date is adequate to show that arsenic in air is mainly in the inorganic form. Reported average concentrations of As(III) and As(V) ranged up to 7.4 and 10.4 ng/m3, respectively, with As(V) being more prevalent than As(III) in most studies. Concentrations of the organic methylated arsenic compounds are negligible (in the pg/m3 range). However because of the variability in study methods and measurement methodology, the authors were unable to determine the variation in arsenic composition as a function of source or particulate matter (PM) fraction. In this work, the authors include the implications of arsenic speciation in air on potential exposure and risks. The authors conclude that it is important to synchronize sample collection, preparation, and analytical techniques in order to generate

  11. Distributed sensing and actuation over bluetooth for unmanned air vehicles

    OpenAIRE

    Afonso, José A.; Coelho, Ezequiel T.; Carvalhal, Paulo; Ferreira, Manuel João Oliveira; Santos, Cristina; Silva, Luís F.; Almeida, Heitor

    2006-01-01

    A short range wireless network platform, based on Bluetooth technology and on a Round Robin scheduling is presented. The objective is to build an application independent platform, to support a distributed sensing and actuation control system, which will be used in an Unmanned Aerial Vehicle (UAV). This platform provides the advantages of wireless communications while assuring low weight, small energy consumption and reliable communications.

  12. Distribution measurement of 60Co target radioactive specific activity

    International Nuclear Information System (INIS)

    Li Xingyan; Chen Zigen; Ren Min

    1994-01-01

    Radioactive specific activity distribution of cobalt 60 target by irradiation in HFETR is a key parameter. With the collimate principle, the under water measurement device and conversion coefficient which is get by experiments, and the radioactive specific activity distribution is obtained. The uncertainty of measurement is less than 10%

  13. A Program to Generate a Particle Distribution from Emittance Measurements

    CERN Document Server

    Bouma, DS; Lallement, JB

    2010-01-01

    We have written a program to generate a particle distribution based on emittance measurements in x-x’ and y-y’. The accuracy of this program has been tested using real and constructed emittance measurements. Based on these tests, the distribution generated by the program can be used to accurately simulate the beam in multi-particle tracking codes, as an alternative to a Gaussian or uniform distribution.

  14. Air Flow and Pressure Drop Measurements Across Porous Oxides

    Science.gov (United States)

    Fox, Dennis S.; Cuy, Michael D.; Werner, Roger A.

    2008-01-01

    This report summarizes the results of air flow tests across eight porous, open cell ceramic oxide samples. During ceramic specimen processing, the porosity was formed using the sacrificial template technique, with two different sizes of polystyrene beads used for the template. The samples were initially supplied with thicknesses ranging from 0.14 to 0.20 in. (0.35 to 0.50 cm) and nonuniform backside morphology (some areas dense, some porous). Samples were therefore ground to a thickness of 0.12 to 0.14 in. (0.30 to 0.35 cm) using dry 120 grit SiC paper. Pressure drop versus air flow is reported. Comparisons of samples with thickness variations are made, as are pressure drop estimates. As the density of the ceramic material increases the maximum corrected flow decreases rapidly. Future sample sets should be supplied with samples of similar thickness and having uniform surface morphology. This would allow a more consistent determination of air flow versus processing parameters and the resulting porosity size and distribution.

  15. Node-to-node field calibration of wireless distributed air pollution sensor network.

    Science.gov (United States)

    Kizel, Fadi; Etzion, Yael; Shafran-Nathan, Rakefet; Levy, Ilan; Fishbain, Barak; Bartonova, Alena; Broday, David M

    2018-02-01

    Low-cost air quality sensors offer high-resolution spatiotemporal measurements that can be used for air resources management and exposure estimation. Yet, such sensors require frequent calibration to provide reliable data, since even after a laboratory calibration they might not report correct values when they are deployed in the field, due to interference with other pollutants, as a result of sensitivity to environmental conditions and due to sensor aging and drift. Field calibration has been suggested as a means for overcoming these limitations, with the common strategy involving periodical collocations of the sensors at an air quality monitoring station. However, the cost and complexity involved in relocating numerous sensor nodes back and forth, and the loss of data during the repeated calibration periods make this strategy inefficient. This work examines an alternative approach, a node-to-node (N2N) calibration, where only one sensor in each chain is directly calibrated against the reference measurements and the rest of the sensors are calibrated sequentially one against the other while they are deployed and collocated in pairs. The calibration can be performed multiple times as a routine procedure. This procedure minimizes the total number of sensor relocations, and enables calibration while simultaneously collecting data at the deployment sites. We studied N2N chain calibration and the propagation of the calibration error analytically, computationally and experimentally. The in-situ N2N calibration is shown to be generic and applicable for different pollutants, sensing technologies, sensor platforms, chain lengths, and sensor order within the chain. In particular, we show that chain calibration of three nodes, each calibrated for a week, propagate calibration errors that are similar to those found in direct field calibration. Hence, N2N calibration is shown to be suitable for calibration of distributed sensor networks. Copyright © 2017 Elsevier Ltd. All

  16. Optimisation of key performance measures in air cargo demand management

    Directory of Open Access Journals (Sweden)

    Alexander May

    2014-04-01

    Full Text Available This article sought to facilitate the optimisation of key performance measures utilised for demand management in air cargo operations. The focus was on the Revenue Management team at Virgin Atlantic Cargo and a fuzzy group decision-making method was used. Utilising intelligent fuzzy multi-criteria methods, the authors generated a ranking order of ten key outcome-based performance indicators for Virgin Atlantic air cargo Revenue Management. The result of this industry-driven study showed that for Air Cargo Revenue Management, ‘Network Optimisation’ represents a critical outcome-based performance indicator. This collaborative study contributes to existing logistics management literature, especially in the area of Revenue Management, and it seeks to enhance Revenue Management practice. It also provides a platform for Air Cargo operators seeking to improve reliability values for their key performance indicators as a means of enhancing operational monitoring power.

  17. The effect of the air blast sprayer speed on the chemical distribution in vineyard.

    Science.gov (United States)

    Celen, I H; Arin, S; Durgut, M R

    2008-06-01

    A study was conducted to determine the spray deposition patterns for air blast sprayers used to apply chemicals to the canopy of Semillon grapevine in vineyard. The application carried out in 12 bars and three sprayer speed (2.1-4.9-7.7 km h(-1)). The spray deposition was measured on the point in the different distances (1.5-3-6-9 m). Tartrazine were applied as tracer material. Maximum spray deposit was obtained 66.1 mg cm(-2) at sprayer speed of 2.1 km h(-1) and minimum deposit was obtained 37.1 mg cm(-2) at sprayer speed of 7.7 km h(-1). The results showed that the sprayer speeds had significant effect on spray deposit distribution and increasing of the sprayer speed increased drift.

  18. Integration of the effects of air quality measures in the SOLVE mix of measures

    International Nuclear Information System (INIS)

    Hesselmans, T.; Heijnis, F.

    2008-01-01

    SOLVE is the Dutch abbreviation for fast solutions for air and traffic and is a website by means of which provinces and municipalities in the Netherlands can gain insight into the best measures for traffic to improve the quality of the ambient air. Since halfway June 2008, the effects on air quality of approximately 35 traffic measures were included in the SOLVE mix of measures. The effects of traffic measures on emissions of particulate matter and nitrogen dioxide have been calculated. The effects are expressed in a decrease of the contribution of traffic indicated in a scale from A (very large decrease) to E (no decrease). The outcome depends on the location where the measure is implemented. [mk] [nl

  19. Temporal and spatial distribution characteristics and influencing factors of air quality index in Xuchang

    Science.gov (United States)

    Wang, Zhenghua; Tian, Zhihui

    2018-01-01

    In recent years, the problem of air pollution becomes more and more serious. Based on the geographic and seasonal climatic characteristics of Xuchang City, this paper studies the temporal and spatial distribution characteristics of air quality index. The results show that: from the time point of view, air quality index shows seasonal difference. Air quality index is highest in winter and is lowest in summer. From the space point of view, there are differences between the north and the south to a certain extent. Changge City, Yuzhou city and central Xuchang county is higher than the southeast of Xiangcheng county and Yanling county. The spatial and temporal variation characteristics of air quality index in Xuchang are influenced by natural factors and human activities, and the economic development and population are the important factors affecting the urban air quality.

  20. Streamlining air import operations by trade facilitation measures

    Directory of Open Access Journals (Sweden)

    Yuri da Cunha Ferreira

    2017-12-01

    Full Text Available Global operations are subject to considerable uncertainties. Due to the Trade Facilitation Agreement that became effective in February 2017, the study of measures to streamline customs controls is urgent. This study aims to assess the impact of trade facilitation measures on import flows. An experimental study was performed in the largest cargo airport in South America through discrete-event simulation and design of experiments. Operation impacts of three trade facilitation measures are assessed on import flow by air. We shed light in the following trade facilitation measures: the use of X-ray equipment for physical inspection; increase of the number of qualified companies in the trade facilitation program; performance targets for customs officials. All trade facilitation measures used indicated potential to provide more predictability, cost savings, time reduction, and increase in security in international supply chain.

  1. Lichen and bryophyte distribution on oak in London in relation to air pollution and bark acidity

    International Nuclear Information System (INIS)

    Larsen, R.S.; Bell, J.N.B.; James, P.W.; Chimonides, P.J.; Rumsey, F.J.; Tremper, A.; Purvis, O.W.

    2007-01-01

    Epiphytic lichen and bryophyte distribution and frequency were investigated on the trunks of 145 young oak trees throughout London and surrounding counties, and compared with pollution levels and bark pH. Sixty-four lichen and four bryophyte species were recorded. Three major zones were identified: (i) two central regions with a few lichens, bryophytes absent; (ii) a surrounding region with a more diverse flora including a high cover of nitrophyte lichens; and (iii) an outer region, characterised by species absent from central London, including acidophytes. Nineteen species were correlated with nitrogen oxides and 16 with bark pH, suggesting that transport-related pollution and bark acidity influence lichen and bryophyte distribution in London today. Lichens and bryophytes are responding to factors that influence human and environmental health in London. Biomonitoring therefore has a practical role to assess the effects of measures to improve London's air quality. - Transport-related pollutants and bark acidity influence lichen and bryophyte distribution and abundance in London today

  2. Differential pressure distribution measurement for the development of insect-sized wings

    International Nuclear Information System (INIS)

    Takahashi, Hidetoshi; Matsumoto, Kiyoshi; Shimoyama, Isao

    2013-01-01

    This paper reports on the measurement of the differential pressure distribution over a flat, thin wing using a micro-electro-mechanical systems sensor. Sensors featuring a piezoresistive cantilever were attached to a polyimide/Cu wing. Because the weight of the cantilever element was less than 10 ng, the sensor can measure the differential pressure without interference from inertial forces, such as wing flapping motions. The dimensions of the sensor chips and the wing were 1.0 mm × 1.0 mm × 0.3 mm and 100 mm × 30 mm × 1 mm, respectively. The differential pressure distribution along the wing's chord direction was measured in a wind tunnel at an air velocity of 4.0 m s –1 by changing the angle of attack. It was confirmed that the pressure coefficient calculated by the measured differential pressure distribution was similar to the value measured by a load cell. (paper)

  3. The applicability of the Poisson distribution in radiochemical measurements

    International Nuclear Information System (INIS)

    Luthardt, M.; Proesch, U.

    1980-01-01

    The fact that, on principle, the Poisson distribution describes the statistics of nuclear decay is generally accepted. The applicability of this distribution to nuclear radiation measurements has recently been questioned. Applying the chi-squared test for goodness of fit on the analogy of the moving average, at least 3 cases may be distinguished, which lead to an incorrect rejection of the Poisson distribution for measurements. Examples are given. Distributions, which make allowance for special parameters, should only be used after careful examination of the data with regard to other interfering effects. The Poisson distribution will further on be applicable to many simple measuring operations. Some basic equations for the analysis of poisson-distributed data are given. (author)

  4. Integrated Assessment of Air Pollution Control Measures for Megacities

    Science.gov (United States)

    Friedrich, R.; Theloke, J.; Denier-van-der-Gon, H.; Kugler, U.; Kampffmeyer, T.; Roos, J.; Torras, S.

    2012-04-01

    Air pollution in large cities is still a matter of concern. Especially the concentration of fine particles (PM10 and PM2.5) is largest in large cities leading to severe health impacts. Furthermore the PM10 thresholds of the EU Air Quality Directive are frequently exceeded. Thus the question arises, whether the initiated policies and measures for mitigating air pollution are sufficient to meet the air quality targets and - if not - which efficient further pollution mitigation measures exist. These questions have been addressed in the EU research project MEGAPOLI for the four European megacities respectively agglomerations London, Paris, Rhine-Ruhr area and Po valley. Firstly, a reference scenario of future activities and emissions has been compiled for the megacities for the years 2020, 2030 and 2050 for all relevant air pollutants (CO, NH3, NMVOC, NOx, PM10, PM2.5 and SO2) and greenhouse gases (CO2, CH4 and N2O). The reference scenario takes into account as well population changes as technical progress and economic growth. As pollution flowing in from outside the city is about as important as pollution caused by emissions in the city, the analysis covers the whole of Europe and not only the city area. Emissions are then transformed into concentrations using atmospheric models. The higher concentrations in cities were estimated with a newly developed 'urban increment' model. Results show, that in the megacities the limits of the Air Quality Directive (2008/50/EC) will be exceeded. Thus additional efforts are necessary to reduce emissions further. Thus, a number of further measures (not implemented in current legislation) were selected and assessed. These included mitigation options for road transport, other mobile sources, large combustion plants, small and medium combustion plants and industry. For each measure and in addition for various bundles of measures a cost-benefit analysis has been carried out. Benefits (avoided health risks and climate change risks) have

  5. Air Quality Science and Regulatory Efforts Require Geostationary Satellite Measurements

    Science.gov (United States)

    Pickering, Kenneth E.; Allen, D. J.; Stehr, J. W.

    2006-01-01

    Air quality scientists and regulatory agencies would benefit from the high spatial and temporal resolution trace gas and aerosol data that could be provided by instruments on a geostationary platform. More detailed time-resolved data from a geostationary platform could be used in tracking regional transport and in evaluating mesoscale air quality model performance in terms of photochemical evolution throughout the day. The diurnal cycle of photochemical pollutants is currently missing from the data provided by the current generation of atmospheric chemistry satellites which provide only one measurement per day. Often peak surface ozone mixing ratios are reached much earlier in the day during major regional pollution episodes than during local episodes due to downward mixing of ozone that had been transported above the boundary layer overnight. The regional air quality models often do not simulate this downward mixing well enough and underestimate surface ozone in regional episodes. Having high time-resolution geostationary data will make it possible to determine the magnitude of this lower-and mid-tropospheric transport that contributes to peak eight-hour average ozone and 24-hour average PM2.5 concentrations. We will show ozone and PM(sub 2.5) episodes from the CMAQ model and suggest ways in which geostationary satellite data would improve air quality forecasting. Current regulatory modeling is typically being performed at 12 km horizontal resolution. State and regional air quality regulators in regions with complex topography and/or land-sea breezes are anxious to move to 4-km or finer resolution simulations. Geostationary data at these or finer resolutions will be useful in evaluating such models.

  6. Calibration of NASA Turbulent Air Motion Measurement System

    Science.gov (United States)

    Barrick, John D. W.; Ritter, John A.; Watson, Catherine E.; Wynkoop, Mark W.; Quinn, John K.; Norfolk, Daniel R.

    1996-01-01

    A turbulent air motion measurement system (TAMMS) was integrated onboard the Lockheed 188 Electra airplane (designated NASA 429) based at the Wallops Flight Facility in support of the NASA role in global tropospheric research. The system provides air motion and turbulence measurements from an airborne platform which is capable of sampling tropospheric and planetary boundary-layer conditions. TAMMS consists of a gust probe with free-rotating vanes mounted on a 3.7-m epoxy-graphite composite nose boom, a high-resolution inertial navigation system (INS), and data acquisition system. A variation of the tower flyby method augmented with radar tracking was implemented for the calibration of static pressure position error and air temperature probe. Additional flight calibration maneuvers were performed remote from the tower in homogeneous atmospheric conditions. System hardware and instrumentation are described and the calibration procedures discussed. Calibration and flight results are presented to illustrate the overall ability of the system to determine the three-component ambient wind fields during straight and level flight conditions.

  7. Advanced air distribution for minimizing airborne cross infection in aircraft cabin

    DEFF Research Database (Denmark)

    Melikov, Arsen Krikor; Dzhartov, Viktor

    2012-01-01

    was ventilated at 180 L/s. The concentration of Freon mixed with air exhaled by the “infected” manikin was measured. The personalized flow pushed the contaminated exhaled air backwards where it was pulled by the suction and exhausted before mixing with the cabin air. This resulted in substantial decrease...... simulated “infected” polluting passenger and another simulated “exposed” passenger. Personalized ventilation supplied clean air at 10 L/s from front against manikins’ face. Air was sucked at 10 L/s by a suction system of two nozzles positioned on the sides of “infected” manikin’s head. The cabin...... of the tracer gas concentration in the air inhaled by the “exposed” manikin and the exhausted cabin air....

  8. Study of air flow and temperature distribution in ship's crew cabins

    Energy Technology Data Exchange (ETDEWEB)

    Elsafty, A.F. [Arab Academy for Science and Technology and Maritime Transport, Alexandria (Egypt). Dept. of Mechanical and Marine Engineering; Ali, A.A.; Nasr, A.N. [Arab Academy for Science and Technology and Maritime Transport, Alexandria (Egypt). Dept. of Marine Engineering Technology

    2007-07-01

    Because of low internal heights in ship's crew cabins, the supplied air is directed to the persons at low mixing ratios. However, this does not allow the mixing process between the supplied air and the indoor air to be completed before the air enters human lungs. This paper presented an experimental and numerical simulation study that used computational fluid dynamics (CFD) to investigate the effect of the air supply location on thermal air diffusion in the ship's crew cabins space. The paper presented the results in terms of air diffusion performance index. The paper presented the CFD model, including selected space configurations; CFD simulation; boundary conditions; and CFD results. The CFD airflow simulation programs CFD were utilized to calculate the spatial distribution of temperature and velocity. The study focused on the typical Middle East region working vessel under thermal and boundary conditions including the high cooling load used in this region. Experimental data were also introduced to verify the CFD results package. It was concluded that the supply should be located near the high sidewall of the cabin. This gives better air distribution inside the space rather than the center of the room. 5 refs., 1 tab., 6 figs.

  9. Canyon air flow measurement utilizing ASME standard pitot tube arrays

    International Nuclear Information System (INIS)

    Moncrief, B.R.

    1990-01-01

    The Savannah River Site produces nuclear materials for national defense. In addition to nuclear reactors, the site has separation facilities for reprocessing irradiated nuclear fuel. The chemical separation of highly radioactive materials takes place by remote control in large buildings called canyons. Personnel in these buildings are shielded from radiation by thick concrete walls. Contaminated air is exhausted from the canyons and contaminants are removed by sand filters prior to release to the atmosphere through a stack. When these facilities were built on a crash basis in the early 1950's, inadequate means were provided for pressure and air flow measurement. This presentation describes the challenge we faced in retrofitting a highly radioactive, heavily shielded facility with instrumentation to provide this capability

  10. First measurement of radon transfer. Water - skin - blood - air

    International Nuclear Information System (INIS)

    Philipsborn, H. von; Grunewald, W.A.

    2000-01-01

    While radon is disliked in uranium mines and homes, it is used medically in radon spas for the treatment of several ailments. The transfer of radon gas from water, through skin into blood and into expiratory air was studied completely for the first time for a person resting 20-30 min in radon water. For waterborne radon concentrations of 1500±100 Bq/L, 4±1 Bq/L were measured in the blood and 2.4±0.5 kBq/m 3 (Bq/L) in the expiratory air. The results can be understood according to the principles of physiology. The nature of the experiments excluded persons other than the authors. Hence the study has been radiometric (physical), not clinical (medical). (orig.)

  11. Measurement of Temporal Awareness in Air Traffic Control

    Science.gov (United States)

    Rantanen, E.M.

    2009-01-01

    Temporal awareness, or level 3 situation awareness, is critical to successful control of air traffic, yet the construct remains ill-defined and difficult to measure. This research sought evidence for air traffic controllers awareness of temporal characteristics of their tasks in data from a high-fidelity system evaluation simulation. Five teams of controllers worked on four scenarios with different traffic load. Several temporal parameters were defined for each task controllers performed during a simulation run and their actions on the tasks were timed relative to them. Controllers showed a strong tendency to prioritize tasks according to a first come, first served principle. This trend persisted as task load increased. Also evident was awareness of the urgency of tasks, as tasks with impending closing of a window of opportunity were performed before tasks that had longer time available before closing of the window.

  12. SCANNING VOLTA POTENTIALS MEASUREMENTS OF METALS IN IRRADIATED AIR.

    Energy Technology Data Exchange (ETDEWEB)

    ISAACS, H.S.; ADZIC, G.; AND ENERGY SCIENCES AND TECHNOLOGY DEPARTMENT; JEFFCOATE, C.S.

    2000-10-22

    A method for direct dc measurement of the Volta potential is presented. High intensity synchrotron x-ray beams were used to locally irradiate the atmosphere adjacent to the metal surface and produce a conducting path between a sample and a reference probe. The direct measurements of potential in the ionized air could be made at probe heights of around 1 mm compared to less than 0.1 mm for the Kelvin probe. The measurements were similar to traditional Kelvin probe measurements, but had a poorer spatial resolution. In contrast to the Kelvin probe methods, the approach described allows observation of the current as a function of impressed voltage. Methods to improve the special resolution of the technique and applications to corrosion under coating will be presented.

  13. Prototype Systems for Measuring Outdoor Air Intake Rates in Rooftop Air Handlers

    Energy Technology Data Exchange (ETDEWEB)

    Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chan, Wanyu R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hotchi, Toshifumi [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-01-01

    The widespread absence of systems for real-time measurement and feedback control, of minimum outdoor air intake rates in HVAC systems contributes to the poor control of ventilation rates in commercial buildings. Ventilation rates affect building energy consumption and influence occupant health. The project designed fabricated and tested four prototypes of systems for measuring rates of outdoor air intake into roof top air handlers. All prototypes met the ±20% accuracy target at low wind speeds, with all prototypes accurate within approximately ±10% after application of calibration equations. One prototype met the accuracy target without a calibration. With two of four prototype measurement systems, there was no evidence that wind speed or direction affected accuracy; however, winds speeds were generally below usually 3.5 m s-1 (12.6 km h-1) and further testing is desirable. The airflow resistance of the prototypes was generally less than 35 Pa at maximum RTU air flow rates. A pressure drop of this magnitude will increase fan energy consumption by approximately 4%. The project did not have resources necessary to estimate costs of mass produced systems. The retail cost of components and materials used to construct prototypes ranged from approximately $1,200 to $1,700. The test data indicate that the basic designs developed in this project, particularly the designs of two of the prototypes, have considerable merit. Further design refinement, testing, and cost analysis would be necessary to fully assess commercial potential. The designs and test results will be communicated to the HVAC manufacturing community.

  14. Human factors measurement for future air traffic control systems.

    Science.gov (United States)

    Langan-Fox, Janice; Sankey, Michael J; Canty, James M

    2009-10-01

    This article provides a critical review of research pertaining to the measurement of human factors (HF) issues in current and future air traffic control (ATC). Growing worldwide air traffic demands call for a radical departure from current ATC systems. Future systems will have a fundamental impact on the roles and responsibilities of ATC officers (ATCOs). Valid and reliable methods of assessing HF issues associated with these changes, such as a potential increase (or decrease) in workload, are of utmost importance for advancing theory and for designing systems, procedures, and training. We outline major aviation changes and how these relate to five key HF issues in ATC. Measures are outlined, compared, and evaluated and are followed by guidelines for assessing these issues in the ATC domain. Recommendations for future research are presented. A review of the literature suggests that situational awareness and workload have been widely researched and assessed using a variety of measures, but researchers have neglected the areas of trust, stress, and boredom. We make recommendations for use of particular measures and the construction of new measures. It is predicted that, given the changing role of ATCOs and profound future airspace requirements and configurations, issues of stress, trust, and boredom will become more significant. Researchers should develop and/or refine existing measures of all five key HF issues to assess their impact on ATCO performance. Furthermore, these issues should be considered in a holistic manner. The current article provides an evaluation of research and measures used in HF research on ATC that will aid research and ATC measurement.

  15. Methods for Sampling and Measurement of Compressed Air Contaminants

    International Nuclear Information System (INIS)

    Stroem, L.

    1976-10-01

    In order to improve the technique for measuring oil and water entrained in a compressed air stream, a laboratory study has been made of some methods for sampling and measurement. For this purpose water or oil as artificial contaminants were injected in thin streams into a test loop, carrying dry compressed air. Sampling was performed in a vertical run, down-stream of the injection point. Wall attached liquid, coarse droplet flow, and fine droplet flow were sampled separately. The results were compared with two-phase flow theory and direct observation of liquid behaviour. In a study of sample transport through narrow tubes, it was observed that, below a certain liquid loading, the sample did not move, the liquid remaining stationary on the tubing wall. The basic analysis of the collected samples was made by gravimetric methods. Adsorption tubes were used with success to measure water vapour. A humidity meter with a sensor of the aluminium oxide type was found to be unreliable. Oil could be measured selectively by a flame ionization detector, the sample being pretreated in an evaporation- condensation unit

  16. Methods for Sampling and Measurement of Compressed Air Contaminants

    Energy Technology Data Exchange (ETDEWEB)

    Stroem, L

    1976-10-15

    In order to improve the technique for measuring oil and water entrained in a compressed air stream, a laboratory study has been made of some methods for sampling and measurement. For this purpose water or oil as artificial contaminants were injected in thin streams into a test loop, carrying dry compressed air. Sampling was performed in a vertical run, down-stream of the injection point. Wall attached liquid, coarse droplet flow, and fine droplet flow were sampled separately. The results were compared with two-phase flow theory and direct observation of liquid behaviour. In a study of sample transport through narrow tubes, it was observed that, below a certain liquid loading, the sample did not move, the liquid remaining stationary on the tubing wall. The basic analysis of the collected samples was made by gravimetric methods. Adsorption tubes were used with success to measure water vapour. A humidity meter with a sensor of the aluminium oxide type was found to be unreliable. Oil could be measured selectively by a flame ionization detector, the sample being pretreated in an evaporation- condensation unit

  17. A comparison of measured and calculated values of air kerma rates from 137Cs in soil

    Directory of Open Access Journals (Sweden)

    V. P. Ramzaev

    2015-01-01

    Full Text Available In 2010, a study was conducted to determine the air gamma dose rate from 137Cs deposited in soil. The gamma dose rate measurements and soil sampling were performed at 30 reference plots from the south-west districts of the Bryansk region (Russia that had been heavily contaminated as a result of the Chernobyl accident. The 137Cs inventory in the top 20 cm of soil ranged from 260 kBq m–2 to 2800 kBq m–2. Vertical distributions of 137Cs in soil cores (6 samples per a plot were determined after their sectioning into ten horizontal layers of 2 cm thickness. The vertical distributions of 137Cs in soil were employed to calculate air kerma rates, K, using two independent methods proposed by Saito and Jacob [Radiat. Prot. Dosimetry, 1995, Vol. 58, P. 29–45] and Golikov et al. [Contaminated Forests– Recent Developments in Risk Identification and Future Perspective. Kluwer Academic Publishers, 1999. – P. 333–341]. A very good coincidence between the methods was observed (Spearman’s rank coefficient of correlation = 0.952; P<0.01; on average, a difference between the kerma rates calculated with two methods did not exceed 3%. The calculated air kerma rates agreed with the measured dose rates in air very well (Spearman’s coefficient of correlation = 0.952; P<0.01. For large grassland plots (n=19, the measured dose rates were on average 6% less than the calculated kerma rates. The tested methods for calculating the air dose rate from 137Cs in soil can be recommended for practical studies in radiology and radioecology. 

  18. Influence of ventilation structure on air flow distribution of large turbo-generator

    Science.gov (United States)

    Zhang, Liying; Ding, Shuye; Zhao, Zhijun; Yang, Jingmo

    2018-04-01

    For the 350 MW air - cooled turbo—generator, the rotor body is ventilated by sub -slots and 94 radial ventilation ducts and the end adopts arc segment and the straight section to acquire the wind. The stator is ventilated with five inlets and eight outlet air branches. In order to analyze the cooling effect of different ventilation schemes, a global physical model including the stator, rotor, casing and fan is established, and the assumptions and boundary conditions of the solution domain are given. the finite volume method is used to solve the problem, and the air flow distribution characteristics of each part of the motor under different ventilation schemes are obtained. The results show that the baffle at the end of the rotor can eliminate the eddy current at the end of the rotor, and make the flow distribution of cooling air more uniform and reasonable. The conclusions can provide reference for the design of motor ventilation structure.

  19. Measurement for cobalt target activity and its axial distribution

    International Nuclear Information System (INIS)

    Li Xingyuan; Chen Zigen.

    1985-01-01

    Cobalt target activity and its axial distribution are measured in process of producing radioactive isotopes 60 Co by irradiation in HFETR. Cobalt target activity is obtained with measured data at 3.60 m and 4.60 m, relative axial distribution of cobalt target activity is obtained with one at 30 cm, and axial distribution of cobalt target activity(or specific activity) is obtained with both of data. The difference between this specific activity and measured result for 60 Co teletherapy sources in the end is less than +- 5%

  20. Questionnaire on the measurement condition of distribution coefficient

    International Nuclear Information System (INIS)

    Takebe, Shinichi; Kimura, Hideo; Matsuzuru, Hideo

    2001-05-01

    The distribution coefficient is used for various transport models to evaluate the migration behavior of radionuclides in the environment and is very important parameter in environmental impact assessment of nuclear facility. The questionnaire was carried out for the purpose of utilizing for the proposal of the standard measuring method of distribution coefficient. This report is summarized the result of questionnairing on the sampling methods and storage condition, the pretreatment methods, the analysis items in the physical/chemical characteristics of the sample, and the distribution coefficient measuring method and the measurement conditions in the research institutes within country. (author)

  1. Dynamics, OH distributions and UV emission of a gliding arc at various flow-rates investigated by optical measurements

    DEFF Research Database (Denmark)

    Zhu, Jiajian; Sun, Zhiwei; Li, Zhongshan

    2014-01-01

    -state OH were investigated using planar laser-induced fluorescence. The results show that the shape, height, intensity and thickness of ground-state OH distribution vary significantly with air flow rates. Finally, UV emission of the gliding arc is measured using optical emission spectroscopy......We demonstrate a plasma discharge which is generated between two diverging electrodes and extended into a gliding arc in non-equilibrium condition by an air flow at atmospheric pressure. Effects of the air flow rates on the dynamics, ground-state OH distributions and spectral characterization of UV...

  2. A method to measure depth distributions of implanted ions

    International Nuclear Information System (INIS)

    Arnesen, A.; Noreland, T.

    1977-04-01

    A new variant of the radiotracer method for depth distribution determinations has been tested. Depth distributions of radioactive implanted ions are determined by dissolving thin, uniform layers of evaporated material from the surface of a backing and by measuring the activity before and after the layer removal. The method has been used to determine depth distributions for 25 keV and 50 keV 57 Co ions in aluminium and gold. (Auth.)

  3. Impact of Air Distribution on Heat Transfer during Night-Time Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per; Artmann, Nikolai; Jensen, Rasmus Lund

    2009-01-01

    Passive cooling by night-time ventilation is seen as a promising approach for energy efficient cooling of buildings. However, uncertainties in prediction of cooling potential and consequenses for thermal comfort restrain architects and engineers from applying this technique. Heat transfer...... at internal room surfaces determines the performance of night-time ventilation. In order to improve predictability, heat transfer mechanism in case of either mixing or displacement ventilation has been investigated in a full scale test room with an exposed ceiling as the dominating thermal mass. The influence...... of air distribution principle, air flow rate and inlet air temperature were investigated. Results show that for low air flow rates displacement ventilation is more efficient than mixing ventilation. For higher airflow rates the air jet flowing along the ceiling has a significant effect, and mixing...

  4. Effectiveness of local air quality measures; Effectiviteit van likale luchtkwaliteitsmaatregelen

    Energy Technology Data Exchange (ETDEWEB)

    Van Bommel, R.; Van de Poll, T. [Royal Haskoning DHV, Amersfoort (Netherlands)

    2013-12-15

    This article examines the effects of local air quality measures which are calculated by order of the city of Utrecht. The conclusions are that environmental zones and other local measures contribute to meet the targets and improve public health. It is also explained why this is the case, and the question is raised whether or not national measures would be better [Dutch] Dit artikel gaat in op de effecten van lokale maatregelen die zijn berekend in opdracht van de gemeente Utrecht. De conclusie: milieuzones en andere lokale maatregelen dragen bij aan het halen van normen en leveren gezondheidswinst op. Er wordt uitgelegd waarom dat zo is en de vraag wordt gesteld of landelijke maatregelen niet beter zijn.

  5. Junge relationships in measurement data for cyclic siloxanes in air.

    Science.gov (United States)

    MacLeod, Matthew; Kierkegaard, Amelie; Genualdi, Susie; Harner, Tom; Scheringer, Martin

    2013-10-01

    In 1974, Junge postulated a relationship between variability of concentrations of gases in air at remote locations and their atmospheric residence time, and this Junge relationship has subsequently been observed empirically for a range of trace gases. Here, we analyze two previously-published datasets of concentrations of cyclic volatile methyl siloxanes (cVMS) in air and find Junge relationships in both. The first dataset is a time series of concentrations of decamethylcyclopentasiloxane (D5) measured between January and June, 2009 at a rural site in southern Sweden that shows a Junge relationship in the temporal variability of the measurements. The second dataset consists of measurements of hexamethylcyclotrisiloxane (D3), octamethylcyclotetrasiloxane (D4) and D5 made simultaneously at 12 sites in the Global Atmospheric Passive Sampling (GAPS) network that shows a Junge relationship in the spatial variability of the three cVMS congeners. We use the Junge relationship for the GAPS dataset to estimate atmospheric lifetimes of dodecamethylcyclohexasiloxane (D6), 8:2-fluorotelomer alcohol and trichlorinated biphenyls that are within a factor of 3 of estimates based on degradation rate constants for reaction with hydroxyl radical determined in laboratory studies. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Chemical composition of aerosol measurements in the air pollution plume during KORUS-AQ

    Science.gov (United States)

    Park, T.; Lee, J. B.; Lim, Y. J.; Ahn, J.; Park, J. S.; Soo, C. J.; Kim, J.; Park, S.; Lee, Y.; Desyaterik, Y.; Collett, J. L., Jr.; Lee, T.

    2017-12-01

    The Korean peninsula is a great place to study different sources of the aerosols: urban, rural and marine. In addition, Seoul is one of the large metropolitan areas in the world and has a variety of sources because half of the Korean population lives in Seoul, which comprises only 12% of the country's area. To understand the chemical composition of aerosol form long-range transport and local sources better, an Aerodyne High Resolution Time of Flight Aerosol Mass Spectrometer (HR-ToF-AMS) was deployed on an airborne platform (NASA DC-8 aircraft). The HR-ToF-AMS is capable of measuring non-refractory size resolved chemical composition of submicron particle(NR-PM1) in the air pollution plume, including mass concentration of organic carbon, nitrate, sulfate, and ammonium with 10 seconds time resolution. The measurements were performed twenty times research flight for understanding characteristic of the air pollution from May to June, 2016 on the South Korean peninsula during KORUS-AQ 2016 campaign. The scientific goal of this study is to characterize aerosol chemical properties and mass concentration in order to understand the role of the long-range transport from northeast Asia to South Korea, and influence of the local sources. To brief, organics dominated during all of flights. Also, organics and nitrate were dominant around energy industrial complex near by Taean, South Korea. The presentation will provide an overview of the composition of NR-PM1 measured in air pollution plumes, and deliver detail information about width, depth and spatial distribution of the pollutant in the air pollution plumes. The results of this study will provide high temporal and spatial resolved details on the air pollution plumes, which are valuable input parameters of aerosol properties for the current air quality models.

  7. Empowering smartphone users with sensor node for air quality measurement

    Science.gov (United States)

    Oletic, Dinko; Bilas, Vedran

    2013-06-01

    We present an architecture of a sensor node developed for use with smartphones for participatory sensing of air quality in urban environments. Our solution features inexpensive metal-oxide semiconductor gas sensors (MOX) for measurement of CO, O3, NO2 and VOC, along with sensors for ambient temperature and humidity. We focus on our design of sensor interface consisting of power-regulated heater temperature control, and the design of resistance sensing circuit. Accuracy of the sensor interface is characterized. Power consumption of the sensor node is analysed. Preliminary data obtained from the CO gas sensors in laboratory conditions and during the outdoor field-test is shown.

  8. Empowering smartphone users with sensor node for air quality measurement

    International Nuclear Information System (INIS)

    Oletic, Dinko; Bilas, Vedran

    2013-01-01

    We present an architecture of a sensor node developed for use with smartphones for participatory sensing of air quality in urban environments. Our solution features inexpensive metal-oxide semiconductor gas sensors (MOX) for measurement of CO, O 3 , NO 2 and VOC, along with sensors for ambient temperature and humidity. We focus on our design of sensor interface consisting of power-regulated heater temperature control, and the design of resistance sensing circuit. Accuracy of the sensor interface is characterized. Power consumption of the sensor node is analysed. Preliminary data obtained from the CO gas sensors in laboratory conditions and during the outdoor field-test is shown.

  9. Distributed Nonstationary Heat Model of Two-Channel Solar Air Heater

    International Nuclear Information System (INIS)

    Klychev, Sh. I.; Bakhramov, S. A.; Ismanzhanov, A. I.; Tashiev, N.N.

    2011-01-01

    An algorithm for a distributed nonstationary heat model of a solar air heater (SAH) with two operating channels is presented. The model makes it possible to determine how the coolant temperature changes with time along the solar air heater channel by considering its main thermal and ambient parameters, as well as variations in efficiency. Examples of calculations are presented. It is shown that the time within which the mean-day efficiency of the solar air heater becomes stable is significantly higher than the time within which the coolant temperature reaches stable values. The model can be used for investigation of the performances of solar water-heating collectors. (authors)

  10. Analysis of the dust particles distribution and ventilation as a way to improve indoor air quality

    Science.gov (United States)

    Kozlovtseva, E. Yu; Azarov, V. N.; Stefanenko, I. V.

    2017-10-01

    The indoor air pollution is analyzed in the article. The subject of the research is the presence and composition of the dust particles taken into “traps” in the working space of the public building (Volgograd State Technical University, Volgograd, the Russian Federation). The research has established the range of sizes of the particulate matter (fractional composition) for the dust in the air of the working space in the form of integral curves for the mass distribution of particles with to their diameters, it also provides the scheme of the air flows movement in the ventilation system of the room.

  11. Electro-optic measurement of terahertz pulse energy distribution

    NARCIS (Netherlands)

    Sun, J.H.; Gallacher, J.G.; Brussaard, G.J.H.; Lemos, N.; Issac, R.; Huang, Z.X.; Dias, J.M.; Jaroszynski, D.A.

    2009-01-01

    An accurate and direct measurement of the energy distribution of a low repetition rate terahertz electromagnetic pulse is challenging because of the lack of sensitive detectors in this spectral range. In this paper, we show how the total energy and energy density distribution of a terahertz

  12. Measurement of neutron flux distribution by semiconductor detector

    International Nuclear Information System (INIS)

    Obradovic, D.; Bosevski, T.

    1964-01-01

    Application of semiconductor detectors for measuring neutron flux distribution is about 10 times faster than measurements by activation foils and demands significantly lower reactor power. Following corrections are avoided: mass of activation foils which influences the self shielding, nuclear decay during activity measurements; counter dead-time. It is possible to control the measured data during experiment and repeat measurements if needed. Precision of the measurement is higher since it is possible to choose the wanted statistics. The method described in this paper is applied for measurements at the RB reactor. It is concluded that the method is suitable for fast measurements but the activation analysis is still indispensable

  13. Distributed collaborative team effectiveness: measurement and process improvement

    Science.gov (United States)

    Wheeler, R.; Hihn, J.; Wilkinson, B.

    2002-01-01

    This paper describes a measurement methodology developed for assessing the readiness, and identifying opportunities for improving the effectiveness, of distributed collaborative design teams preparing to conduct a coccurent design session.

  14. Measurement of C-14 distribution in forest around nuclear facilities

    International Nuclear Information System (INIS)

    Atarashi-Andoh, Mariko; Amano, Hikaru; Arakhatoon, Jahan

    2003-01-01

    A simple analytical method of C-14 measurement using fast bomb combustion and liquid scintillation counting (LSC) has been developed for measuring C-14 distribution in the terrestrial environment. Specific activities of C-14 in cedar leaves and soils collected from an area around nuclear facilities and control areas were measured using this method. Depth distribution of Cs-137 in soils was also measured at the same sampling sites and compared with the depth distribution of C-14. C-14 specific activity in cedar leaves examined around nuclear facilities exceeded that in the control areas by 8 to 30 mBq (g carbon) -1 . The depth distribution of C-14 in forest soil shows that C-14 has peak values in the top 10 cm of the soil profiles ascribed to the highest bomb C-14 level in the 1960's. The data were made available to assess the behavior of fallout C-14 in the surface environment. (author)

  15. Time series behaviour of the number of Air Asia passengers: A distributional approach

    Science.gov (United States)

    Asrah, Norhaidah Mohd; Djauhari, Maman Abdurachman

    2013-09-01

    The common practice to time series analysis is by fitting a model and then further analysis is conducted on the residuals. However, if we know the distributional behavior of time series, the analyses in model identification, parameter estimation, and model checking are more straightforward. In this paper, we show that the number of Air Asia passengers can be represented as a geometric Brownian motion process. Therefore, instead of using the standard approach in model fitting, we use an appropriate transformation to come up with a stationary, normally distributed and even independent time series. An example in forecasting the number of Air Asia passengers will be given to illustrate the advantages of the method.

  16. Electron-photon shower distribution function tables for lead, copper and air absorbers

    CERN Document Server

    Messel, H

    2013-01-01

    Electron-Photon Shower Distribution Function: Tables for Lead, Copper and Air Absorbers presents numerical results of the electron-photon shower distribution function for lead, copper, and air absorbers. Electron or photon interactions, including Compton scattering, elastic Coulomb scattering, and the photo-electric effect, are taken into account in the calculations. This book consists of four chapters and begins with a review of both theoretical and experimental work aimed at deducing the characteristics of the cascade produced from the propagation of high energy electrons and photons through

  17. Apparatus for power and breeding distribution measurements in breeder reactors

    International Nuclear Information System (INIS)

    Goldstein, N.P.; Sun, K.H.

    1975-01-01

    A detection system is disclosed herein for the measurement of power and breeding distribution inside a breeder reactor. Small diameter BeO balls comprising oxides of 235 U and 238 U are inserted into the reactor for activation and withdrawn to be counted in a Ge(Li) counter. Measurements of the activated fission and 239 Np gamma rays yield the desired distributions. (Official Gazette)

  18. Optimisation of Design of Air Inlets in Air Distribution Channels of a Double-Skin Transparent Façade

    Science.gov (United States)

    Bielek, Boris; Szabó, Daniel; Palko, Milan; Rychtáriková, Monika

    2017-12-01

    This paper reports on an optimization of design of air inlets in naturally ventilated double-skin transparent facades; the design aims at the proper functioning of these facades from the point of view of their aerodynamic and hydrodynamic behaviour. A comparison was made of five different variants of ventilation louvers used in air openings with different shapes, positions and overall geometry. The aerodynamic response of the louvers was determined by 2D simulations using ANSYS software. The hydrodynamic properties were investigated by conducting driven-rain measurements in a large rain chamber at the Slovak University of Technology in Bratislava.

  19. Optimisation of Design of Air Inlets in Air Distribution Channels of a Double-Skin Transparent Façade

    Directory of Open Access Journals (Sweden)

    Bielek Boris

    2017-12-01

    Full Text Available This paper reports on an optimization of design of air inlets in naturally ventilated double-skin transparent facades; the design aims at the proper functioning of these facades from the point of view of their aerodynamic and hydrodynamic behaviour. A comparison was made of five different variants of ventilation louvers used in air openings with different shapes, positions and overall geometry. The aerodynamic response of the louvers was determined by 2D simulations using ANSYS software. The hydrodynamic properties were investigated by conducting driven-rain measurements in a large rain chamber at the Slovak University of Technology in Bratislava.

  20. A Practical Device for Measuring the Luminance Distribution

    Directory of Open Access Journals (Sweden)

    Thijs Kruisselbrink

    2017-06-01

    Full Text Available Various applications in building lighting such as automated daylight systems, dynamic lighting control systems, lighting simulations, and glare analyzes can be optimized using information on the actual luminance distributions of the surroundings. Currently, commercially available luminance distribution measurement devices are often not suitable for these kind of applications or simply too expensive for broad application. This paper describes the development of a practical and autonomous luminance distribution measurement device based on a credit card-sized single-board computer and a camera system. The luminance distribution was determined by capturing High Dynamic Range images and translating the RGB information to the CIE XYZ color space. The High Dynamic Range technology was essential to accurately capture the data needed to calculate the luminance distribution because it allows to capture luminance ranges occurring in real scenarios. The measurement results were represented in accordance with established methods in the field of daylighting. Measurements showed that the accuracy of the luminance distribution measurement device ranged from 5% to 20% (worst case which was deemed acceptable for practical measurements and broad applications in the building realm.

  1. Problems in air traffic management. VII., Job training performance of air traffic control specialists - measurement, structure, and prediction.

    Science.gov (United States)

    1965-07-01

    A statistical study of training- and job-performance measures of several hundred Air Traffic Control Specialists (ATCS) representing Enroute, Terminal, and Flight Service Station specialties revealed that training-performance measures reflected: : 1....

  2. The indigenous Sea Gypsy divers of Thailand's west coast: measurement of carbon monoxide in the breathing air.

    Science.gov (United States)

    Gold, D; Geater, A; Aiyarak, S; Juengpraert, W

    1999-07-01

    Approximately 400 indigenous divers live and work on Thailand's west coast. They dive with surface supplied air from primitive compressor units mounted on open boats which measure from seven to 11 meters in length. It was suspected that carbon monoxide was present in the breathing air of at least the gasoline-driven compressor units. To determine the presence of carbon monoxide gas in the breathing air, compressed air from the compressor was pumped through the diver air supply hose through a plenum (monitoring) chamber established on the boat. After a compressor warm-up of 15 minutes, the diving air was measured with the boat at eight different bearings to the wind, each 45 degrees apart at intervals of five minutes. Three of the four gasoline-driven compressor units tested showed presence of carbon monoxide in the breathing air. One diesel-driven unit showed a very low concentration of carbon monoxide (3-4 ppm) and six diesel-driven units showed no detectable carbon monoxide. Although not tested, diesel exhaust emissions could also enter the breathing air by the same route. A locally made modification to the compressor air intake was designed and successfully tested on one gasoline-driven compressor unit. An information sheet on the hazards of carbon monoxide as well as on the modification has been developed for distribution among the villages.

  3. Superthermal electron distribution measurements from polarized electron cyclotron emission

    International Nuclear Information System (INIS)

    Luce, T.C.; Efthimion, P.C.; Fisch, N.J.

    1988-06-01

    Measurements of the superthermal electron distribution can be made by observing the polarized electron cyclotron emission. The emission is viewed along a constant magnetic field surface. This simplifies the resonance condition and gives a direct correlation between emission frequency and kinetic energy of the emitting electron. A transformation technique is formulated which determines the anisotropy of the distribution and number density of superthermals at each energy measured. The steady-state distribution during lower hybrid current drive and examples of the superthermal dynamics as the runaway conditions is varied are presented for discharges in the PLT tokamak. 15 refs., 8 figs

  4. Leaf wettability as a measure of air pollution effects

    International Nuclear Information System (INIS)

    Jagels, R.

    1994-01-01

    Droplet contact angle (DCA) is a technique that can be used to measure wettability and, in turn, provide an assessment of the physical and chemical characteristics of a surface. As adapted to plant bioligy, DCA measurements have been useful in characterizing changes in the type or condition of leaf epicuticular waxes. Environmental as well as temporal factors can modify the biophysical features of epicuticular wax surfaces and thereby affect DCA measurements. An understanding of the role of these non-pollutant factors is necessary before pollution damage can be accurately assessed. Controlled chamber experiments and field pollutant gradient studies have shown that DCA is generally reduced when plants are exposed to air pollutants such as ozone, So 2 , and acidic fog. In some cases, environmental influences, such as temperature, have been separated from the pollutant effect. However, mixtures of anthropogenic pollutants or anthropogenic and natural compounds (sea salts, dust particles) which are often present in field studies can confound the interpretation of DCA measurements. A few studies that attempt to separate these factors have been conducted, but more are needed before the potential for using DCA measurements in long-term bioindicator studies can be fully realized. Some studies have demonstrated that pollutants do not necessarily affect leaf surfaces in a uniform pattern, but rather are specific for certain structures such as stomates or trichomes; deposition levels can also be different on ad-and abaxial surfaces. The degree to which these inhomogeneities of action can affect DCA measurements needs further study. (orig.)

  5. Nondestructive measurement for radionuclide concentration distribution in soil column

    International Nuclear Information System (INIS)

    Ogawa, Hiromichi; Ohnuki, Toshihiko; Yamamoto, Tadatoshi; Wadachi, Yoshiki

    1985-01-01

    A nondestructive method has been studied for determining the concentration of radionuclide (Cs-137) distributed in a soil column. The concentration distribution was calculated from the counting rate distribution using the efficiency matrix of a detector. The concentration distribution obtained by this method, with measuring efficiencies of theoretical calculation, coincides well with that obtained by the destructive sampling method. This method is, therefore, found to be effective for the measurement of one dimensional concentration distribution. The measuring limit of this method is affected not only by the radionuclide concentration but also by the shape of concentration distribution in a soil column and also by the way it is divided into concentration blocks. It is found that, the radioactive concentration up to 2.6 x 10 -4 μCi/g (9.62 Bq/g), and also the distribution up to where the concentration reduces to half at every 1 cm of depth, can be measured by this system. The concentration blocks can be divided into 1 cm of thickness as a minimum value. (author)

  6. Measurements of radioactive dust in high altitude air

    International Nuclear Information System (INIS)

    Kobayashi, Mika; Kohara, Eri; Muronoi, Naohiro; Masuda, Yousuke; Midou, Tomotaka; Ishida, Yukiko; Shimizu, Toshihiko; Saga, Minoru; Endo, Hiromu

    2012-01-01

    The radioactivity in samples of airborne dust was measured. The samples had been collected at high altitude by the Japan Air Self-Defense Force. The data were obtained for the gross beta activity, gamma nuclide determination and radiochemical analysis. It was shown that there was no appreciable difference between the activity levels obtained in this time and in the year before. Seasonal variations were not very pronounced. It was found that the radioactivity at high altitude had been stable at a low level. Radioactive gases (gaseous radioiodine and xenon gas) were not detected. This report does not include the result on radionuclide measurements that Technical Research and Development Institute executed for examining the nuclear emergency situation at Fukushima Daiichi and Daini nuclear power plants after Tohoku Region Pacific Ocean Earthquake on March 11, 2011. (author)

  7. Radon measurements technique in air using a track plastic detector

    International Nuclear Information System (INIS)

    Pereira, J.F.A.; Silva Estrada, J.J. da; Binns, D.A.C.; Urban, M.

    1983-01-01

    A difusion chamber is used to measure the radon concentration in air through alpha particles tracks in Makrofol E, 300μm thick. This system was developed by Karlsruhe Nuclear Research Centre, Germany, and is already used by the Occupational Radiological Protection Department of IRD/CNEN, for premilimar measurements in Pocos de Caldas and Rio de Janeiro. In the chamber, the plastic detector is set at the lower end and a filter is placed at the upper end. In this way, a known volume is defined in the detector system. To amplify the tracks produced by the alpha particles due to radon and short-lived dadon-daughter products, an electrochemical system is employed. Some theoretical questions about the treeing produced by the electrochemical etching, the detector characteristics, as well as the adapted statistics model are also discussed. (Author) [pt

  8. A multimethodological approach to study the spatial distribution of air pollution in an Alpine valley during wintertime

    Directory of Open Access Journals (Sweden)

    R. Schnitzhofer

    2009-05-01

    Full Text Available In order to investigate the spatial distribution of air pollutants in the Inn valley (Tyrol, Austria during wintertime, a joint field campaign of the three research projects ALPNAP (Monitoring and Minimisation of Traffic-Induced Noise and Air Pollution Along Major Alpine Transport Routes, INNAP (Boundary Layer Structure in the Inn Valley during high Air Pollution and INNOX (NOx-structure in the Inn Valley during High Air Pollution was carried out in January/February 2006. In addition to continuous ground based measurements, vertical profiles of various air pollutants and meteorological parameters were obtained on six selected days. For in-situ investigations, a tethered balloon was used to analyse the lowest atmospheric layers, 0–500 m above the valley bottom (a.v.b., and a research aircraft sampled at 150–2200 m a.v.b. An aircraft equipped with an aerosol backscatter lidar performed nadir measurements at 3000 m a.v.b. Combined results from a typical day show a strongly polluted layer up to about 125 m a.v.b. in the morning. Around midday concentrations on the valley floor decrease indicating some vertical air exchange despite thermally stable conditions. Strong vertical and horizontal gradients with enhanced pollution levels along the sunny side of the valley up to 1300 m a.v.b. were observed in the afternoon. This vertical mixing due to thermally or dynamically driven slope winds reduces the concentration of air pollutants at the bottom of the valley and causes the formation of elevated pollution layers.

  9. Diurnal and seasonal variation in air exchange rates and interzonal airflows measured by active and passive tracer gas in homes

    DEFF Research Database (Denmark)

    Bekö, Gabriel; Gustavsen, Sine; Frederiksen, Marie

    2016-01-01

    Outdoor air delivery to buildings is an important parameter in the assessment of pollutant exposure indoors. Detailed and well controlled measurements of air exchange rates (AER) and interzonal airflows in residential environment are scarce. We measured the outdoor AERs in up to six rooms in five...... rooms. Window opening behavior had a strong influence on AERs, which were highest during occupied daytime periods, lowest in the night; highest in the summer, lowest in the winter. Significant differences were found between AERs measured by the different techniques. The median nighttime AER in all...... studied the pollutant distribution from one room (source room) and interzonal airflows across the dwellings. The air within a given floor was well mixed, with the average tracer gas concentration in the non-source rooms reaching approximately 70% of the source room concentration. There was less air...

  10. Measurement and Numerical Simulation of Air Velocity in a Tunnel-Ventilated Broiler House

    Directory of Open Access Journals (Sweden)

    Eliseo Bustamante

    2015-02-01

    Full Text Available A building needs to be designed for the whole period of its useful life according to its requirements. However, future climate predictions involve some uncertainty. Thus, several sustainable strategies of adaptation need to be incorporated after the initial design. In this sense, tunnel ventilation in broiler houses provides high air velocity values (2–3 m·s−1 at animal level to diminish their thermal stress and associated mortality. This ventilation system was experimentally incorporated into a Mediterranean climate. The aim was to resolve these thermal problems in hot seasons, as (traditional cross-mechanical ventilation does not provide enough air velocity values. Surprisingly, very little information on tunnel ventilation systems is available, especially in terms of air velocity. Using Computational Fluid Dynamics (CFD and a multi-sensor system, the average results are similar (at animal level: 1.59 ± 0.68 m·s−1 for CFD and 1.55 ± 0.66 m·s−1 for measurements. The ANOVA for validation concluded that the use of CFD or measurements is not significant (p-value = 0.1155. Nevertheless, some problems with air velocity distribution were found and need to be solved. To this end, CFD techniques can help by means of virtual designs and scenarios providing information for the whole indoor space.

  11. Development of System Architecture to Investigate the Impact of Integrated Air and Missile Defense in a Distributed Lethality Environment

    Science.gov (United States)

    2017-12-01

    SYSTEM ARCHITECTURE TO INVESTIGATE THE IMPACT OF INTEGRATED AIR AND MISSILE DEFENSE IN A DISTRIBUTED LETHALITY ENVIRONMENT by Justin K. Davis...TO INVESTIGATE THE IMPACT OF INTEGRATED AIR AND MISSILE DEFENSE IN A DISTRIBUTED LETHALITY ENVIRONMENT 5. FUNDING NUMBERS 6. AUTHOR(S) Justin K...ARCHITECTURE TO INVESTIGATE THE IMPACT OF INTEGRATED AIR AND MISSILE DEFENSE IN A DISTRIBUTED LETHALITY ENVIRONMENT Justin K. Davis Lieutenant

  12. Measuring distributed leadership agency in a hospital context

    DEFF Research Database (Denmark)

    Jønsson, Thomas; Unterrainer, Christine; Jeppesen, Hans Jeppe

    2016-01-01

    and valid quantitative instrument that measures how much employees’ at all hierarchical levels are involved in concrete leadership activities in the hospital context. Taking a normative perspective we could show that Distributed Leadership – measured with the DLA-questionnaire – has positive effects......Purpose: The purpose of this study is to develop and validate an instrument that can measure Distributed Leadership as employees’ active participation in distributed leadership tasks. We designate this as the Distributed Leadership Agency (DLA). Methodology: Data were collected throughout all......, discriminant and convergent validity, and ANOVAs were applied to analyze group differences in DLA. Findings: The identified uni-dimensional questionnaire consists of seven items, as it is different from, but associated with, empowering leadership, organizational influence, attitude to participation and trust...

  13. Pulmonary blood flow distribution measured by radionuclide computed tomography

    International Nuclear Information System (INIS)

    Maeda, H.; Itoh, H.; Ishii, Y.

    1982-01-01

    Distributions of pulmonary blood flow per unit lung volume were measured in sitting patients with a radionuclide computed tomography (RCT) by intravenously administered Tc-99m macroaggregates of human serum albumin (MAA). Four different types of distribution were distinguished, among which a group referred as type 2 had a three zonal blood flow distribution as previously reported (West and co-workers, 1964). The pulmonary arterial pressure (Pa) and the venous pressure (Pv) were determined in this group of distribution. These values showed satifactory agreements with the pulmonary artery pressure (Par) and the capillary wedged pressure (Pcw) measured by Swan-Ganz catheter in eighteen supine patients. Those good correlations enable to establish a noninvasive methodology for measurement of pulmonary vascular pressures

  14. Air

    International Nuclear Information System (INIS)

    Gugele, B.; Scheider, J.; Spangl, W.

    2001-01-01

    In recent years several regulations and standards for air quality and limits for air pollution were issued or are in preparation by the European Union, which have severe influence on the environmental monitoring and legislation in Austria. This chapter of the environmental control report of Austria gives an overview about the legal situation of air pollution control in the European Union and in specific the legal situation in Austria. It gives a comprehensive inventory of air pollution measurements for the whole area of Austria of total suspended particulates, ozone, volatile organic compounds, nitrogen oxides, sulfur dioxide, carbon monoxide, heavy metals, benzene, dioxin, polycyclic aromatic hydrocarbons and eutrophication. For each of these pollutants the measured emission values throughout Austria are given in tables and geographical charts, the environmental impact is discussed, statistical data and time series of the emission sources are given and legal regulations and measures for an effective environmental pollution control are discussed. In particular the impact of fossil-fuel power plants on the air pollution is analyzed. (a.n.)

  15. Problems in the measurement of electron-dose distribution with film dosimeters inserted into solid materials

    International Nuclear Information System (INIS)

    Okuda, Shuichi; Fukuda, Kyue; Tabata, Tatsuo; Okabe, Shigeru

    1981-01-01

    On the insertion of film dosimeters into solid materials, thin air gaps are formed. The influence of such gaps on measured profiles of depth-dose distributions was investigated for aluminum irradiated with collimated beams of 15-MeV electrons. Measurements were made by changing the gap width or the incidence angle of the electrons. The present results showed that streaming of incident electrons through the gaps resulted in the appearance of a peak and a minimum in a depth-dose curve measured. This effect was suppressed by the increase of the angle between the film and the electron-beam axis. (author)

  16. Mobile Air Monitoring: Measuring Change in Air Quality in the City of Hamilton, 2005-2010

    Science.gov (United States)

    Adams, Matthew D.; DeLuca, Patrick F.; Corr, Denis; Kanaroglou, Pavlos S.

    2012-01-01

    This paper examines the change in air pollutant concentrations between 2005 and 2010 occurring in the City of Hamilton, Ontario, Canada. After analysis of stationary air pollutant concentration data, we analyze mobile air pollutant concentration data. Air pollutants included in the analysis are CO, PM[subscript 2.5], SO[subscript 2], NO,…

  17. Diurnal and seasonal variation in air exchange rates and interzonal flows measured by active tracer gas in five Danish homes

    DEFF Research Database (Denmark)

    Clausen, Geo; Bekö, Gabriel; Toftum, Jørn

    2016-01-01

    We measured the air exchange rates (AER) in up to six rooms in five naturally ventilated dwellings across four seasons using active tracer gas. Night time AER was also estimated in all bedrooms based on occupant-generated CO2. Additionally, we studied the pollutant distribution across the dwellin...

  18. Ventilation distribution in rats: Part I - The effect of gas composition as measured with electrical impedance tomography

    Directory of Open Access Journals (Sweden)

    Dunster Kimble R

    2012-09-01

    Full Text Available Abstract The measurement of ventilation distribution is currently performed using inhaled tracer gases for multiple breath inhalation studies or imaging techniques to quantify spatial gas distribution. Most tracer gases used for these studies have properties different from that of air. The effect of gas density on regional ventilation distribution has not been studied. This study aimed to measure the effect of gas density on regional ventilation distribution. Methods Ventilation distribution was measured in seven rats using electrical impedance tomography (EIT in supine, prone, left and right lateral positions while being mechanically ventilated with either air, heliox (30% oxygen, 70% helium or sulfur hexafluoride (20% SF6, 20% oxygen, 60% air. The effect of gas density on regional ventilation distribution was assessed. Results Gas density did not impact on regional ventilation distribution. The non-dependent lung was better ventilated in all four body positions. Gas density had no further impact on regional filling characteristics. The filling characteristics followed an anatomical pattern with the anterior and left lung showing a greater impedance change during the initial phase of the inspiration. Conclusion It was shown that gas density did not impact on convection dependent ventilation distribution in rats measured with EIT.

  19. The experimental investigation of refrigerant distribution and leaking characteristics of R290 in split type household air conditioner

    International Nuclear Information System (INIS)

    Tang, Weier; He, Guogeng; Cai, Dehua; Zhu, Yihao; Zhang, Aoni; Tian, Qiqi

    2017-01-01

    Highlights: • A new quasi-liquid nitrogen method (QLNM) was proposed and firstly applied in experiments. • The R290 distribution was investigated by QLNM and the results proved the validation. • A solenoid valve was proposed to install near the capillary in STHAC in order to reduce risk factor. • R290 leaking rate was firstly measured by QLNM before and after the installation a solenoid valve. - Abstract: As a high-profile replacement for R22 split type household air conditioner (STHAC), R290 has several advantages in terms of thermodynamic properties, environmental characteristics, and cost. However, the obvious shortcoming of R290 is its flammability, which has a potential fire risk to the building. At present, the most important measure to ensure the safety of a R290 STHAC is to limit the refrigerant charge by domestic and international standards. But in fact, when the leakage of R290 occur from a STHAC, the distribution of R290 in STHAC, and the leaking rate also will seriously affect the safety of an R290 STHAC. In this study, a new quasi-liquid nitrogen method (QLNM) has been proposed in order to investigate the refrigerant distribution in R290 STHACs and the leaking rate under various conditions, and the experiments have been conducted. The experimental results of distribution proved the validation of the QLNM and showed that a large portion of the refrigerant distributed in the condenser when the air conditioner is on running stage and the refrigerant will migrate from the condenser to the evaporator when the air conditioner is on closed stage. Based on this, the installation of a solenoid valve near the capillary has been proposed. The comparison of experimental results of R290 leaking rate before and after the installation of a solenoid valve showed it will obviously reduce the leaking rate and thereby improve the safety of the R290 STHACs.

  20. Particle size distribution measurements of radionuclides from Chernobyl

    International Nuclear Information System (INIS)

    Georgi, B.; Tschiersch, J.

    1988-01-01

    Characteristics of the size distribution of the Chernobyl aerosol have been measured at four locations along the trajectory of the cloud. Changes in time and differences between 131 I and the other isotopes are explained by aerosol physical processes. The relevance of the measurements for dose calculations are discussed

  1. INDIAN POINT REACTOR REACTIVITY AND FLUX DISTRIBUTION MEASUREMENTS

    Energy Technology Data Exchange (ETDEWEB)

    Batch, M. L.; Fischer, F. E.

    1963-11-15

    The reactivity of the Indian Point core was measured near zero reactivity at various shim and control rod patterns. Flux distribution measurements were also made, and the results are expressed in terms of power peaking factors and normalized detector response during rod withdrawal. (D.L.C.)

  2. Comparing downside risk measures for heavy tailed distributions

    NARCIS (Netherlands)

    Daníelsson, J.; Jorgensen, B.N.; Sarma, M.; Vries, de C.G.

    2006-01-01

    Using regular variation to define heavy tailed distributions, we show that prominent downside risk measures produce similar and consistent ranking of heavy tailed risk. Thus, regardless of the particular risk measure being used, assets will be ranked in a similar and consistent manner for heavy

  3. A new setup to measure bidirectional reflectance distribution functions

    NARCIS (Netherlands)

    Roosjen, P.P.J.; Clevers, J.G.P.W.; Bartholomeus, H.

    2012-01-01

    The Plant Facility, a new laboratory goniometer system, built by the Wageningen University has been tested in order to take bidirectional reflectance distribution function (BRDF) measurements. An ASD FieldSpec 3 spectroradiometer mounted on an industrial robot arm is able to measure small targets

  4. Velocity Distribution in a Room Ventilated by Displacement Ventilation and Wall-Mounted Air Terminal Devices

    DEFF Research Database (Denmark)

    Nielsen, Peter Vilhelm

    2000-01-01

    The article describes experiments with wall-mounted air terminal devices. The airflow from an air terminal device influences the occupants' thermal comfort and, therefore, it is important to develop an expression for this flow in the occupied zone. The velocity at the floor is influenced...... by the flow rate to the room, the temperature difference and the type of diffuser. The flow is stratified at Archimedes numbers larger than four. The article gives expressions for the velocity distribution close to the floor. It is shown that openings between obstacles placed directly on the floor generate...... a flow similar to the air movement in front of a diffuser, and expressions for the velocity distribution in that situation are also given in the article....

  5. Distribution and rate of microbial processes in ammonia-loaded air filter biofilm

    DEFF Research Database (Denmark)

    Juhler, Susanne; Nielsen, Lars Peter; Schramm, Andreas

    2009-01-01

    The in situ activity and distribution of heterotrophic and nitrifying bacteria and their potential interactions were investigated in a full-scale, two-section, trickling filter designed for biological degradation of volatile organics and NH3 in ventilation air from pig farms. The filter biofilm...

  6. Spatial distribution of nanocrystals imaged at the liquid-air interface

    NARCIS (Netherlands)

    Rijssel, J.; van der Linden, Marte; Meeldijk, J.D.; van Dijk-Moes, R.J.A.; Philipse, A.P.; Erné, B.H.

    2013-01-01

    The 3D distribution of nanocrystals at the liquid-air interface is imaged for the first time on a single-particle level by cryogenic electron tomography, revealing the equilibrium concentration profile from the interface to the bulk of the liquid. When the surface tension of the liquid is decreased,

  7. Air Distribution Effectiveness for Residential Mechanical Ventilation: Simulation and Comparison of Normalized Exposures

    Energy Technology Data Exchange (ETDEWEB)

    Petithuguenin, T.D.P.; Sherman, M.H.

    2009-05-01

    The purpose of ventilation is to dilute indoor contaminants that an occupant is exposed to. Even when providing the same nominal rate of outdoor air, different ventilation systems may distribute air in different ways, affecting occupants' exposure to household contaminants. Exposure ultimately depends on the home being considered, on source disposition and strength, on occupants' behavior, on the ventilation strategy, and on operation of forced air heating and cooling systems. In any multi-zone environment dilution rates and source strengths may be different in every zone and change in time, resulting in exposure being tied to occupancy patterns.This paper will report on simulations that compare ventilation systems by assessing their impact on exposure by examining common house geometries, contaminant generation profiles, and occupancy scenarios. These simulations take into account the unsteady, occupancy-tied aspect of ventilation such as bathroom and kitchen exhaust fans. As most US homes have central HVAC systems, the simulation results will be used to make appropriate recommendations and adjustments for distribution and mixing to residential ventilation standards such as ASHRAE Standard 62.2.This paper will report on work being done to model multizone airflow systems that are unsteady and elaborate the concept of distribution matrix. It will examine several metrics for evaluating the effect of air distribution on exposure to pollutants, based on previous work by Sherman et al. (2006).

  8. Measurement of light-atom distributions in solids

    International Nuclear Information System (INIS)

    Blewer, R.S.

    1977-01-01

    We have developed a sensitive technique that is capable of nondestructively measuring the abundance and depth-distribution of isotopes of hydrogen or helium imbedded in a solid. The measurement is a form of ion-backscattering spectrometry which uses protons to probe within approximately 10μm of the surface of a solid. By analyzing the energy of the backscattered protons we can determine the number of atoms of a given mass present at various depths in the target material. This method permits detection of the lightest elements (i.e., those most difficult to detect by conventional ion-backscattering spectrometry) without sacrificing the capability of revealing the abundance and depth-distribution of heavier elements. For example, we have measured the initial distribution of helium implanted in a metal, then in subsequent measurements kept track of the helium migration

  9. Measurement of Air Pollution Comes from Adra Cement Factory

    International Nuclear Information System (INIS)

    Odat, M.; Meslmani, Y.; Al-Kharfan, K.; Shamali, K.

    2013-06-01

    Measurements of air pollution were carried out in and around Adra cement factory during a single period (December). The Measurements included the following: 1- Dust fall. 2- Total suspended particulates (TSP) and inhalable particulates PM-1-0 & PM-3 inside the factor and in residential area surrounded the factory (Worker City of Adra, Adra city, Wafeden Mokheam, Baironi Hospital and Alkatiefa City). 3-Determination the levels of Cd, Pb, Cu and zinc associated with air born. 4- Determination of toxic gases (CO, SO-2 and NO-x) emitted from the chimneys. The results showed that the quantity of dust fall was varied obviously inside the factory and the regions affected by air pollutions. The monthly concentration of dust fall were 165, 27 and 10 tons/Km 2 /month inside the factory , affected villages and Baironi Hospital respectively, Wherein the permissible limit is (9tons/Km'2/month). The total suspended particulates (TSP) and inhalable particulates PM-1-0 & PM-3 in the studies area were higher than the permissible limit. The TSP concentrations inside the factory ranged between 497 and 2021 microgram/m'3 while the ranged between 328 and 561 microgram /m'3 in the surrounded villages and between 232 and 244 microgram/m'3 near Damascus, the were far higher than the world health organization (WHO) standards (120 Microgram/m'3). The PM-3 which is the most effecting on the human health reached 117.6, 124.6 and 62.6 microgram /m 3 inside the factory (main in trance), city worker of Adra and Baironi Hospital respectively, theses concentrations were higher than the Syrian standards (15 microgram/m'3) The measurements which were carried out through an exclusive day refered that the percentage of TSP/PM-3 is increasedwith moving away from the factory and reached 6.8, 18.6, 19.3% in the main intrance of the factory, worker city of Adra and Bironi Hospital respectively. The level of toxic gases inside the source (chimneys) was within the standards

  10. Dynamic Models of Heating and Cooling Coils with One—Dimensional Air Distribution

    Institute of Scientific and Technical Information of China (English)

    WangZijie; G.Krauss

    1993-01-01

    This paper presents the simulation models of the plate-fin,air-to-water(or water vapour) heat exchangers used as air-heating or air-cooling and dehumidifying colis in the HVAC(Heating,Ventilation and AIr-Conditioning)systems.The thermal models are used to calculate the heat exchange between distributing air and coil pipes and outlet temperatures of air and heat or chilled fluid.The aerodynamic models are used to account for the pressure drop of the air crossing the coil tubes,They can also be used to optimize the structres of such coils.The models are based on principal laws of teat and mass conservation and fluid mechanics.They are transparent and easy to use.In our work,a coil is considered as an assembly of numbers of basic elements in which all the state variables are unique.Therefore we can conveniently simulate the coils with different structures and different geometric parameters.Two modular programs TRNSYS(Transient System Simulation)and ESACAP are utilized as supporting softwares which make the programming and simulation greatly simplified.The coil elements and a real coil were simulated.The results were compared with the data offered by the manufacturer(company SOFICA) and also with those obtained using critical methods such as NTU method ,etc.and good agreement is attained.

  11. Particle number size distributions in urban air before and after volatilisation

    Directory of Open Access Journals (Sweden)

    W. Birmili

    2010-05-01

    Full Text Available Aerosol particle number size distributions (size range 0.003–10 μm in the urban atmosphere of Augsburg (Germany were examined with respect to the governing anthropogenic sources and meteorological factors. The two-year average particle number concentration between November 2004 and November 2006 was 12 200 cm−3, i.e. similar to previous observations in other European cities. A seasonal analysis yielded twice the total particle number concentrations in winter as compared to summer as consequence of more frequent inversion situations and enhanced particulate emissions. The diurnal variations of particle number were shaped by a remarkable maximum in the morning during the peak traffic hours. After a mid-day decrease along with the onset of vertical mixing, an evening concentration maximum could frequently be observed, suggesting a re-stratification of the urban atmosphere. Overall, the mixed layer height turned out to be the most influential meteorological parameter on the particle size distribution. Its influence was even greater than that of the geographical origin of the prevailing synoptic-scale air mass.

    Size distributions below 0.8 μm were also measured downstream of a thermodenuder (temperature: 300 °C, allowing to retrieve the volume concentration of non-volatile compounds. The balance of particle number upstream and downstream of the thermodenuder suggests that practically all particles >12 nm contain a non-volatile core while additional nucleation of particles smaller than 6 nm could be observed after the thermodenuder as an interfering artifact of the method. The good correlation between the non-volatile volume concentration and an independent measurement of the aerosol absorption coefficient (R2=0.9 suggests a close correspondence of the refractory and light-absorbing particle fractions. Using the "summation method", an average diameter ratio of particles before and after volatilisation could

  12. Phantoms for IMRT dose distribution measurement and treatment verification

    International Nuclear Information System (INIS)

    Low, Daniel A.; Gerber, Russell L.; Mutic, Sasa; Purdy, James A.

    1998-01-01

    Background: The verification of intensity-modulated radiation therapy (IMRT) patient treatment dose distributions is currently based on custom-built or modified dose measurement phantoms. The only commercially available IMRT treatment planning and delivery system (Peacock, NOMOS Corp.) is supplied with a film phantom that allows accurate spatial localization of the dose distribution using radiographic film. However, measurements using other dosimeters are necessary for the thorough verification of IMRT. Methods: We have developed a phantom to enable dose measurements using a cylindrical ionization chamber and the localization of prescription isodose curves using a matrix of thermoluminescent dosimetry (TLD) chips. The external phantom cross-section is identical to that of the commercial phantom, to allow direct comparisons of measurements. A supplementary phantom has been fabricated to verify the IMRT dose distributions for pelvis treatments. Results: To date, this phantom has been used for the verification of IMRT dose distributions for head and neck and prostate cancer treatments. Designs are also presented for a phantom insert to be used with polymerizing gels (e.g., BANG-2) to obtain volumetric dose distribution measurements. Conclusion: The phantoms have proven useful in the quantitative evaluation of IMRT treatments

  13. Measurement of size distribution for 220Rn progeny attached aerosols

    International Nuclear Information System (INIS)

    Zhang Lei; Guo Qiuju; Zhuo Weihai

    2008-01-01

    The size distribution of radioactive aerosols is a very important factor for evaluating the inner exposure dose contributed by radon and thoron progeny in environments. In order to measure the size distribution of thoron progeny attached radioactive aerosols, a device was developed using wire screens. The count median diameter (CMD) and the geometric standard deviation (GSD) of attached radioactive aerosols were calculated by collecting ThB and using CR-39 as detector. Field measurement results at Yangjiang City in Guangdong Province show that the CMDs distribute between 30 and 130 nm, and the GSDs are between 1.9 and 3.3. It also shows that the more humid country, the smaller CMDs, and the ventilation has great influence on the size distribution of aerosols. The CMDs of adobe house are smaller than that of the concrete houses. (authors)

  14. Indoor air quality in cold climates: hazards and abatement measures

    National Research Council Canada - National Science Library

    Walkinshaw, D. S

    1986-01-01

    The first APCA Conference on Indoor Air Quality, held April 29, 30 and May 1, 1985 in Ottawa, featured some 67 presentations covering many aspects of indoor air quality, with the focus on cold climate...

  15. Measurement of agglomerate strength distributions in agglomerated powders

    International Nuclear Information System (INIS)

    Ciftcioglu, M.; Aking, M.; Burkhart, L.

    1986-01-01

    Strength distributions of particle agglomerates in six different yttria powders were measured using a calibrated ultrasonic sound field. The density of sintered pellets was directly related to the agglomerate strength of each powder. No systematic relation to the sintered density was observed for bulk densities or pressure-density compaction data for the loose powders, or for pore size distributions or green densities for the pressed compacts

  16. Project 'European Research Center for Air Pollution Abatement Measures'

    International Nuclear Information System (INIS)

    1985-04-01

    During the 5-7th of March 1985 the first status report of the project 'European Research Center for Air Pollution Control Measures' took place in the Nuclear Research Center, Karlsruhe. Progress reports on the following topics assessment and analysis of the impacts of airborne pollutants on forest trees; distinction from other potential causes of recent forest dieback, research into atmospheric dispersion, conversion and deposition of airborne pollutants, development and optimization of industrial-technical processes to reduce or avoid emissions and providing instruments and making recommendations to the industrial and political sectors were presented. This volume is a collection of the work reported there. 42 papers were entered separately. (orig./MG) [de

  17. Scaling precipitation input to spatially distributed hydrological models by measured snow distribution

    Directory of Open Access Journals (Sweden)

    Christian Vögeli

    2016-12-01

    Full Text Available Accurate knowledge on snow distribution in alpine terrain is crucial for various applicationssuch as flood risk assessment, avalanche warning or managing water supply and hydro-power.To simulate the seasonal snow cover development in alpine terrain, the spatially distributed,physics-based model Alpine3D is suitable. The model is typically driven by spatial interpolationsof observations from automatic weather stations (AWS, leading to errors in the spatial distributionof atmospheric forcing. With recent advances in remote sensing techniques, maps of snowdepth can be acquired with high spatial resolution and accuracy. In this work, maps of the snowdepth distribution, calculated from summer and winter digital surface models based on AirborneDigital Sensors (ADS, are used to scale precipitation input data, with the aim to improve theaccuracy of simulation of the spatial distribution of snow with Alpine3D. A simple method toscale and redistribute precipitation is presented and the performance is analysed. The scalingmethod is only applied if it is snowing. For rainfall the precipitation is distributed by interpolation,with a simple air temperature threshold used for the determination of the precipitation phase.It was found that the accuracy of spatial snow distribution could be improved significantly forthe simulated domain. The standard deviation of absolute snow depth error is reduced up toa factor 3.4 to less than 20 cm. The mean absolute error in snow distribution was reducedwhen using representative input sources for the simulation domain. For inter-annual scaling, themodel performance could also be improved, even when using a remote sensing dataset from adifferent winter. In conclusion, using remote sensing data to process precipitation input, complexprocesses such as preferential snow deposition and snow relocation due to wind or avalanches,can be substituted and modelling performance of spatial snow distribution is improved.

  18. HYPERION NET - a distributed measurement system for monitoring background ionizing radiation

    International Nuclear Information System (INIS)

    Saponjic, Dj.; Zigic, A.; Arandjelovic, V.

    2003-01-01

    The distributed measurement system - HYPERION NET, based on the concept of FieldBus technology, has been developed, implemented, and tested as a pilot project, the first WEB enabled on-line networked ionizing radiation monitoring and measurement system. The Net has layered the structure, tree topology, and is based on the Internet infrastructure and TCP/IP communication protocol. The Net's core element is an intelligent GM transmitter, based on GM tube, used for measuring the absorbed dose in air, in the range of 0.087 to 720 μGy/h. The transmitter makes use of an advanced count rate measurement algorithm capable of suppressing the statistical fluctuations of the measured quantity, which significantly improves its measurement performance mailing it suitable for environmental radiation measurements. (author)

  19. Aerosol concentration measurements and correlations with air mass trajectories at the Pierre Auger Observatory

    Science.gov (United States)

    Micheletti, M. I.; Louedec, K.; Freire, M.; Vitale, P.; Piacentini, R. D.

    2017-06-01

    Aerosols play an important role in radiative transfer processes involved in different fields of study. In particular, their influence is crucial in the attenuation of light at astronomical and astrophysical observatories, and has to be taken into account in light transfer models employed to reconstruct the signals. The Andean Argentinean region is increasingly being considered as a good candidate to host such facilities, as well as the ones for solar-energy resources, and an adequate knowledge of aerosols characteristics there is needed, but it is not always possible due to the vast area involved and the scarce atmospheric data at ground. The aim of this work is to find correlations between aerosol data and particle trajectories that can give an insight into the origin and behaviour of aerosols in this zone and can be employed in situations in which one does not have local aerosol measurements. For this purpose, an aerosol spectrometer and dust monitor (Grimm 1.109) was installed at the Pierre Auger Observatory of ultra-high-energy cosmic rays, to record aerosol concentrations in different size intervals, at surface level. These measurements are analysed and correlated with air mass trajectories obtained from HYSPLIT (NOAA) model calculations. High aerosol concentrations are registered predominantly when air masses have travelled mostly over continental areas, mainly from the NE direction, while low aerosol concentrations are found in correspondence with air masses coming from the Pacific Ocean, from the NW direction. Different size distribution patterns were found for the aerosols depending on their origin: marine or continental. This work shows for the first time the size distribution of aerosols registered at the Pierre Auger Observatory. The correlations found between mass and particle concentrations (total and for different size ranges) and HYSPLIT air mass trajectories, confirm that the latter can be employed as a useful tool to infer the sources, evolution

  20. Size distribution measurements and chemical analysis of aerosol components

    Energy Technology Data Exchange (ETDEWEB)

    Pakkanen, T.A.

    1995-12-31

    The principal aims of this work were to improve the existing methods for size distribution measurements and to draw conclusions about atmospheric and in-stack aerosol chemistry and physics by utilizing size distributions of various aerosol components measured. A sample dissolution with dilute nitric acid in an ultrasonic bath and subsequent graphite furnace atomic absorption spectrometric analysis was found to result in low blank values and good recoveries for several elements in atmospheric fine particle size fractions below 2 {mu}m of equivalent aerodynamic particle diameter (EAD). Furthermore, it turned out that a substantial amount of analyses associated with insoluble material could be recovered since suspensions were formed. The size distribution measurements of in-stack combustion aerosols indicated two modal size distributions for most components measured. The existence of the fine particle mode suggests that a substantial fraction of such elements with two modal size distributions may vaporize and nucleate during the combustion process. In southern Norway, size distributions of atmospheric aerosol components usually exhibited one or two fine particle modes and one or two coarse particle modes. Atmospheric relative humidity values higher than 80% resulted in significant increase of the mass median diameters of the droplet mode. Important local and/or regional sources of As, Br, I, K, Mn, Pb, Sb, Si and Zn were found to exist in southern Norway. The existence of these sources was reflected in the corresponding size distributions determined, and was utilized in the development of a source identification method based on size distribution data. On the Finnish south coast, atmospheric coarse particle nitrate was found to be formed mostly through an atmospheric reaction of nitric acid with existing coarse particle sea salt but reactions and/or adsorption of nitric acid with soil derived particles also occurred. Chloride was depleted when acidic species reacted

  1. Spatial distribution measured by the modulation transfer function

    International Nuclear Information System (INIS)

    Rossi, P.; Brice, D.K.; Doyle, B.L.

    2003-01-01

    Spatial distributions in ion micro-beam and IBA experimental practice are regularly characterized through the parameters of FWHM and tail area percentage (TF, tail fraction). Linear and stationary transducer theory allows these distributions to be described in the Fourier-dual frequency space, and provides an indirect method to evaluate them through measurement of the modulation transfer function (MTF). We suggest direct measurement of MTF by employing bar pattern grids, similar to those used for calibration of radiological equipment. Assuming spatial distributions of the form exp(-(|αx|) η ), we are able to relate the MTF measurements to the more popular FWHM and TF. This new approach to determine spatial resolution can become a standard for use by the micro-beam community

  2. Two-Dimensional Electron Density Measurement of Positive Streamer Discharge in Atmospheric-Pressure Air

    Science.gov (United States)

    Inada, Yuki; Ono, Ryo; Kumada, Akiko; Hidaka, Kunihiko; Maeyama, Mitsuaki

    2016-09-01

    The electron density of streamer discharges propagating in atmospheric-pressure air is crucially important for systematic understanding of the production mechanisms of reactive species utilized in wide ranging applications such as medical treatment, plasma-assisted ignition and combustion, ozone production and environmental pollutant processing. However, electron density measurement during the propagation of the atmospheric-pressure streamers is extremely difficult by using the conventional localized type measurement systems due to the streamer initiation jitters and the irreproducibility in the discharge paths. In order to overcome the difficulties, single-shot two-dimensional electron density measurement was conducted by using a Shack-Hartmann type laser wavefront sensor. The Shack-Hartmann sensor with a temporal resolution of 2 ns was applied to pulsed positive streamer discharges generated in an air gap between pin-to-plate electrodes. The electron density a few ns after the streamer initiation was 7*1021m-3 and uniformly distributed along the streamer channel. The electron density and its distribution profile were compared with a previous study simulating similar streamers, demonstrating good agreement. This work was supported in part by JKA and its promotion funds from KEIRIN RACE. The authors like to thank Mr. Kazuaki Ogura and Mr. Kaiho Aono of The University of Tokyo for their support during this work.

  3. DISCOVER-AQ: an innovative approach to study the vertical distribution of air quality constituents in the Earth's atmosphere

    Science.gov (United States)

    Wisthaler, Armin; Crawford, James H.; Müller, Markus; Mikoviny, Tomas; Cady-Pereira, Karen E.

    2014-05-01

    DISCOVER-AQ (Deriving Information on Surface Conditions from Column and Vertically Resolved Observations Relevant to Air Quality) is a multi-year NASA research project to improve remote sensing of air quality from space. Satellite-based measurements of air pollutants typically provide information integrated over the total atmospheric column while it is the lowermost part of the atmosphere that is of interest from a public health perspective. DISCOVER-AQ has implemented a new field observation strategy to collect a comprehensive dataset on the vertical distribution of air pollutants in the atmosphere. In situ measurements from the NASA P-3B Airborne Science Laboratory generate profile information of air quality constituents over a set of selected ground monitoring sites. Ground and profile information is tied to column information collected by active and passive remote sensors looking downward from a second King Air aircraft flying higher in the atmosphere above the P-3B. Vertical profiles of air pollutants are measured repetitively during different times of the day and under different meteorological conditions occurring in the timeframe of 1-month field campaigns. Targeted regions in the U.S. affected by poor air quality include the Washington/Baltimore metropolitan area (June/July 2011), the San Joaquin Valley in California (January/February 2013), the Houston metropolitan area (September 2013) and the Northern Front Range area in Colorado (June/July 2014). Herein, we will present the DISCOVER-AQ project to the European community and show preliminary analyses of the obtained data. The latter will focus on non-methane hydrocarbons and ammonia, being the species measured by our newly developed airborne PTR-ToF-MS instrument (see session AS4.17). In situ ammonia data collected over the San Joaquin Valley are in promising agreement with satellite data obtained from the Tropospheric Emission Spectrometer (TES). Web site: http://discover-aq.larc.nasa.gov/ Funding

  4. Measurement of radioactivity in air at the linear accelerator of Kyoto University reactor facility

    International Nuclear Information System (INIS)

    Ikebe, Yukimasa; Shimo, Michikuni

    1976-01-01

    It is well-known that the induced activities from a number of nuclides are generated in air during the operation of high energy accelerators. Of these, measurements were performed with the linear accelerator of Kyoto University reactor facility for the purpose of the clarification of the production mechanism and behavior of radioactive aerosols. The concentration in air and the size distribution of 13 N aerosols which have aerosols as the carrier among 13 N produced by the γ-n reaction of 14 N were measured with filter packs and by diffusion method, respectively. The density of number and size distribution of non-radioactive aerosols were measured to understand the production mechanism and behavior of 13 N aerosols. For the aerosol number density, Aitken nucleus number was measured with a Pollak counter. The results obtained show that (1) under the operating condition of the linear accelerator at that measurement time, 13 N aerosol concentration was (2 to 50) x 10 -13 Ci/cm 3 while 13 N gas component concentration was (1 to 25) x 10 -12 Ci/cm 3 , i.e. the ratio was approximately 1 : 10 (2) the average size of 13 N aerosols was 0.01 to 0.04 μm, and it was found that there was positive correlation to relative humidity; (3) during the operation of the accelerator, the generation of aerosols 10 to 100 times as much as the background level was observed. The size distribution of aerosols showed a peak around 0.01 μm; and others. Examination was carried out regarding a 13 N aerosol production model based on the sticking of aerosol-free 13 N to aerosols. (Wakatsuki, Y.)

  5. Field Measurements of Perceived Air Quality in the Test-Bed for Innovative Climate Conditioning Technologies

    DEFF Research Database (Denmark)

    Kolarik, Jakub; Toftum, Jørn; Kabrhel, Michal

    the potential influence of aforementioned technologies on the perceived air quality. Additionally, the effect of Demand Controlled Ventilation (DCV) on the perceived air quality was tested. Measurements comprised of the assessments of perceived air quality and objective measurements of operative temperature...

  6. Air-Sea Interaction Measurements from the Controlled Towed Vehicle

    Science.gov (United States)

    Khelif, D.; Bluth, R. T.; Jonsson, H.; Barge, J.

    2014-12-01

    The Controlled Towed Vehicle (CTV) uses improved towed drone technology to actively maintain via a radar altimeter and controllable wing a user-set height that can be as low as the canonical reference height of 10 m above the sea surface. After take-off, the drone is released from the tow aircraft on a ~700-m stainless steel cable. We have instrumented the 0.23 m diameter and 2.13 m long drone with high fidelity instruments to measure the means and turbulent fluctuations of 3-D wind vector, temperature, humidity, pressure, CO2 and IR sea surface temperature. Data are recorded internally at 40 Hz and simultaneously transmitted to the tow aircraft via dedicated wireless Ethernet link. The CTV accommodates 40 kg of instrument payload and provides it with 250 W of continuous power through a ram air propeller-driven generator. Therefore its endurance is only limited by that of the tow aircraft.We will discuss the CTV development, the engineering challenges and solutions that have been successfully implemented to overcome them. We present results from recent flights as low as 9 m over the coastal ocean and comparisons of profiles and turbulent fluxes from the CTV and the tow aircraft. Manned aircraft operation at low-level boundary-layer flights is very limited. Dropsondes and UAS (Unmanned Aerial Systems) and UAS are alternates for measurements near the ocean surface. However, dropsondes have limited sensor capability and do not measure fluxes, and most present UAS vehicles do not have the payload and power capacity nor the low-flying ability in high winds over the oceans. The CTV therefore, fills a needed gap between the dropsondes, in situ aircraft, and UAS. The payload, capacity and power of the CTV makes it suitable for a variety of atmospheric research measurements. Other sensors to measure aerosol, chemistry, radiation, etc., could be readily accommodated in the CTV.

  7. Mathematical simulation of gamma-radiation angle distribution measurements

    International Nuclear Information System (INIS)

    Batij, V.G.; Batij, E.V.; Egorov, V.V.; Fedorchenko, D.V.; Kochnev, N.A.

    2008-01-01

    We developed mathematical model of the facility for gamma-radiation angle distribution measurement and calculated response functions for gamma-radiation intensities. We developed special software for experimental data processing, the 'Shelter' object radiation spectra unfolding and Sphere detector (ShD) angle resolution estimation. Neuronet method using for detection of the radiation directions is given. We developed software based on the neuronet algorithm, that allows obtaining reliable distribution of gamma-sources that make impact on the facility detectors at the measurement point. 10 refs.; 15 figs.; 4 tab

  8. Power operation, measurement and methods of calculation of power distribution

    International Nuclear Information System (INIS)

    Lindahl, S.O.; Bernander, O.; Olsson, S.

    1982-01-01

    During the initial fuel loading of a BWR core, extensive checks and measurements of the fuel are performed. The measurements are designed to verify that the reactor can always be safely operated in compliance with the regulatory constraints. The power distribution within the reactor core is evaluated by means of instrumentation and elaborate computer calculations. The power distribution forms the basis for the evaluation of thermal limits. The behaviour of the reactor during the ordinary modes of operation as well as during transients shall be well understood and such that the integrity of the fuel and the reactor systems is always well preserved. (author)

  9. The radio emission pattern of air showers as measured with LOFAR—a tool for the reconstruction of the energy and the shower maximum

    NARCIS (Netherlands)

    Nelles, A.; Buitink, S.; Corstanje, A.; Enriquez, J. E.; Falcke, H.; Hörandel, J. R.; Rachen, J. P.; Rossetto, L.; Schellart, P.; Scholten, O.; ter Veen, S.; Thoudam, S.; Trinh, Gia

    2015-01-01

    The pattern of the radio emission of air showers is finely sampled with the Low-Frequency ARray (LOFAR). A set of 382 measured air showers is used to test a fast, analytic parameterization of the distribution of pulse powers. Using this parameterization we are able to reconstruct the shower axis and

  10. Within-Crop Air Temperature and Humidity Outcomes on Spatio-Temporal Distribution of the Key Rose Pest Frankliniella occidentalis.

    Science.gov (United States)

    Fatnassi, Hicham; Pizzol, Jeannine; Senoussi, Rachid; Biondi, Antonio; Desneux, Nicolas; Poncet, Christine; Boulard, Thierry

    2015-01-01

    Frankliniella occidentalis (Pergande) is a key pest of various crops worldwide. In this study, we analyse the dependence of the infestation of this pest on spatially distributed micro climatic factors in a rose greenhouse. Despite the importance of this subject, the few existing studies have been realized in laboratory rather than in greenhouse conditions. However, recent progress on greenhouse microclimate characterisation has highlighted the strong indoor climate heterogeneity that may influence the within-crop pest distribution. In this study, both microclimate (air temperature and humidity) and thrips distribution were simultaneously mapped in a rose greenhouse. The measurements were sensed in a horizontal plane situated at mid-height of the rose crop inside the greenhouse. Simultaneously, thrips population dynamics were assessed after an artificial and homogeneous infestation of the rose crop. The spatio-temporal distribution of climate and thrips within the greenhouse were compared, and links between thrips infestation and climatic conditions were investigated. A statistical model was used to define the favourable climate conditions for thrips adults and larvae. Our results showed that (i) the air temperature and air humidity were very heterogeneously distributed within the crop, (ii) pest populations aggregated in the most favourable climatic areas and (iii) the highest population density of thrips adults and larvae were recorded at 27°C and 22°C for temperature and 63% and 86% for humidity, respectively. These findings confirm, in real rose cropping conditions, previous laboratory studies on the F. occidentalis climatic optimum and provide a solid scientific support for climatic-based control methods against this pest.

  11. Within-Crop Air Temperature and Humidity Outcomes on Spatio-Temporal Distribution of the Key Rose Pest Frankliniella occidentalis.

    Directory of Open Access Journals (Sweden)

    Hicham Fatnassi

    Full Text Available Frankliniella occidentalis (Pergande is a key pest of various crops worldwide. In this study, we analyse the dependence of the infestation of this pest on spatially distributed micro climatic factors in a rose greenhouse. Despite the importance of this subject, the few existing studies have been realized in laboratory rather than in greenhouse conditions. However, recent progress on greenhouse microclimate characterisation has highlighted the strong indoor climate heterogeneity that may influence the within-crop pest distribution. In this study, both microclimate (air temperature and humidity and thrips distribution were simultaneously mapped in a rose greenhouse. The measurements were sensed in a horizontal plane situated at mid-height of the rose crop inside the greenhouse. Simultaneously, thrips population dynamics were assessed after an artificial and homogeneous infestation of the rose crop. The spatio-temporal distribution of climate and thrips within the greenhouse were compared, and links between thrips infestation and climatic conditions were investigated. A statistical model was used to define the favourable climate conditions for thrips adults and larvae. Our results showed that (i the air temperature and air humidity were very heterogeneously distributed within the crop, (ii pest populations aggregated in the most favourable climatic areas and (iii the highest population density of thrips adults and larvae were recorded at 27°C and 22°C for temperature and 63% and 86% for humidity, respectively. These findings confirm, in real rose cropping conditions, previous laboratory studies on the F. occidentalis climatic optimum and provide a solid scientific support for climatic-based control methods against this pest.

  12. Measurement of the refractive index of air in a low-pressure regime and the applicability of traditional empirical formulae

    Science.gov (United States)

    Schödel, René; Walkov, Alexander; Voigt, Michael; Bartl, Guido

    2018-06-01

    The refractive index of air is a major limiting factor in length measurements by interferometry, which are mostly performed under atmospheric conditions. Therefore, especially in the last century, measurement and description of the air refractive index was a key point in order to achieve accuracy in the realisation of the length by interferometry. Nevertheless, interferometric length measurements performed in vacuum are much more accurate since the wavelength of the light is not affected by the air refractive index. However, compared with thermal conditions in air, in high vacuum heat conduction is missing. In such a situation, dependent on the radiative thermal equilibrium, a temperature distribution can be very inhomogeneous. Using a so-called contact gas instead of high vacuum is a very effective way to enable heat conduction on nearly the same level as under atmospheric pressure conditions whereby keeping the effect of the air refractive index on a small level. As physics predicts, and as we have demonstrated previously, helium seems like the optimal contact gas because of its large heat conduction and its refractive index that can be calculated from precisely known parameters. On the other hand, helium gas situated in a vacuum chamber could easily be contaminated, e.g. by air leakage from outside. Above the boiling point of oxygen (‑183 °C) it is therefore beneficial to use dry air as a contact gas. In such an approach, the air refractive index could be calculated based on measured quantities for pressure and temperature. However, existing formulas for the air refractive index are not valid in the low-pressure regime. Although it seems reasonable that the refractivity (n  ‑  1) of dry air simply downscales with the pressure, to our knowledge there is no experimental evidence for the applicability of any empirical formula. This evidence is given in the present paper which reports on highly accurate measurements of the air refractive index for the

  13. New measurements and analysis of high-energy muons in cosmic ray extensive air showers

    International Nuclear Information System (INIS)

    Sarkar, S.K.; Ghose, B.; Murkherjee, N.; Sanyal, S.; Chaudhuri, N.; Chhetri, R.; Basak, D.K.

    1991-01-01

    Cosmic ray air shower structure measurements and measurement of density and energy of air shower muons of a wide energy range simultaneously in individual air showers by two magnet spectrographs are presented. The measured muon densities have been used to compare with some of the previous measurements on muon densities in air showers of nearly the same size. The measured muon densities have also been applied for distinguishing between various interaction models and between light and heavier air shower primaries. In the air shower size range 10 4 -10 6 particles the present measurements do not provide evidence for iron primaries and the different interaction models seem not to be distinguishable by air shower observations. (Author)

  14. EPA scientists develop Federal Reference & Equivalent Methods for measuring key air pollutants

    Science.gov (United States)

    EPA operates a nationwide air monitoring network to measure six primary air pollutants: carbon monoxide, lead, sulfur dioxide, ozone, nitrogen dioxide, and particulate matter as part of its mission to protect human health and the environment.

  15. Back-trajectory modeling of high time-resolution air measurement data to separate nearby sources

    Science.gov (United States)

    Strategies to isolate air pollution contributions from sources is of interest as voluntary or regulatory measures are undertaken to reduce air pollution. When different sources are located in close proximity to one another and have similar emissions, separating source emissions ...

  16. Distribution of trace gases and aerosols in the Siberian air shed during wildfires of summer 2012

    Science.gov (United States)

    Belan, Boris D.; Paris, Jean-Daiel; Nedelec, Philippe; Antokhin, Pavel N.; Arshinova, Victoriya; Arshinov, Mikhail Yu.; Belan, Sergey B.; Davydov, Denis K.; Ivlev, Georgii A.; Fofonov, Alexandre V.; Kozlov, Artem V.; Rasskazchikova, Tatyana M.; Savkin, Denis E.; Simonenkov, Denis V.; Sklyadneva, Tatyana K.; Tolmachev, Gennadii N.

    2017-04-01

    During the last two decades, three strong biomass burning events have been observed in Russia: two of them in 2002 and 2010 in the European part of Russia, and another one in 2012 in West and East Siberia. In this paper we present results of the extensive airborne study of the vertical distribution of trace gases and aerosols carried out during strong wildfire event happened in summer 2012 in Siberia. For this purpose, the Optik TU-134 aircraft laboratory was used as a research platform. A large-scale airborne campaign has been undertaken along the route Novosibirsk-Mirny-Yakutsk-Bratsk-Novosibirsk on 31st of July and 1st of August, 2012. Flight pattern consisted of a number of ascents and descents between close to the ground and 8 km altitude that enabled 20 vertical profiles to be obtained. Campaign was conducted under the weather conditions of low-gradient baric field that determined the low speed transport of air masses, as well as the accumulation of biomass burning emissions in the region under study. Highest concentrations of CO2, CH4 and CO over wildfire spots reached 432 ppm, 2367 ppb, and 4036 ppb, correspondingly. If we exclude from the analysis the data obtained when crossing smoke plumes, we can find a difference between background concentrations measured in the atmosphere over regions affected by biomass burning and clean areas. Enhancement of CO2 over the wildfire areas changed with altitude. On average, it was 10.5 ppm in the atmospheric boundary layer (ABL) and 5-6 ppm in the free troposphere. Maximum CO2 enhancements reached 27 ppm and 24 ppm, correspondingly. The averaged CH4 enhancement varied from 75 ppb in the boundary layer to 30 ppb in the upper troposphere, and a little bit lower than 30 ppb in the middle troposphere. Maximum CH4 enhancements reached 202 ppb, 108 ppb, and 50-60 ppb, correspondingly. The averaged and maximum enhancements of CO differed by an order of magnitude. Thus, in the ABL the maximum difference in concentration between

  17. Ethnic differences in anthropometric measures and abdominal fat distribution

    DEFF Research Database (Denmark)

    Rønn, Pernille F; Andersen, Gregers S; Lauritzen, Torsten

    2017-01-01

    Background Ethnic variation in abdominal fat distribution may explain differences in cardiometabolic risk between populations. However, the ability of anthropometric measures to quantify abdominal fat is not clearly understood across ethnic groups. The aim of this study was to investigate...... across ethnic groups. Thus, the obesity level at which Inuit and Africans are at increased cardiometabolic risk is likely to differ from that of Europeans....... differences most apparent at higher levels of the anthropometric measures. Similar ethnic differences were seen in the associations with SAT for a given anthropometric measure. Conclusions Conventional anthropometric measures like BMI and waist circumference do not reflect the same amount of VAT and SAT...

  18. Development, enhancement, and evaluation of aircraft measurement techniques for national ambient air quality standard criteria pollutants

    Science.gov (United States)

    Brent, Lacey Cluff

    The atmospheric contaminants most harmful to human health are designated Criteria Pollutants. To help Maryland attain the national ambient air quality standards (NAAQS) for Criteria Pollutants, and to improve our fundamental understanding of atmospheric chemistry, I conducted aircraft measurements in the Regional Atmospheric Measurement Modeling Prediction Program (RAMMPP). These data are used to evaluate model simulations and satellite observations. I developed techniques for improving airborne observation of two NAAQS pollutants, particulate matter (PM) and nitrogen dioxide (NO2). While structure and composition of organic aerosol are important for understanding PM formation, the molecular speciation of organic ambient aerosol remains largely unknown. The spatial distribution of reactive nitrogen is likewise poorly constrained. To examine water-soluble organic aerosol (WSOA) during an air pollution episode, I designed and implemented a shrouded aerosol inlet system to collect PM onto quartz fiber filters from a Cessna 402 research aircraft. Inlet evaluation conducted during a side-by-side flight with the NASA P3 demonstrated agreement to within 30%. An ion chromatographic mass spectrometric method developed using the NIST Standard Reference Material (SRM) 1649b Urban Dust, as a surrogate material resulted in acidic class separation and resolution of at least 34 organic acids; detection limits approach pg/g concentrations. Analysis of aircraft filter samples resulted in detection of 8 inorganic species and 16 organic acids of which 12 were quantified. Aged, re-circulated metropolitan air showed a greater number of dicarboxylic acids compared to air recently transported from the west. While the NAAQS for NO2 is rarely exceeded, it is a precursor molecule for ozone, America's most recalcitrant pollutant. Using cavity ringdown spectroscopy employing a light emitting diode (LED), I measured vertical profiles of NO2 (surface to 2.5 km) west (upwind) of the Baltimore

  19. Phase distribution measurements in narrow rectangular channels using image processing techniques

    International Nuclear Information System (INIS)

    Bentley, C.; Ruggles, A.

    1991-01-01

    Many high flux research reactor fuel assemblies are cooled by systems of parallel narrow rectangular channels. The HFIR is cooled by single phase forced convection under normal operating conditions. However, two-phase forced convection or two phase mixed convection can occur in the fueled region as a result of some hypothetical accidents. Such flow conditions would occur only at decay power levels. The system pressure would be around 0.15 MPa in such circumstances. Phase distribution of air-water flow in a narrow rectangular channel is examined using image processing techniques. Ink is added to the water and clear channel walls are used to allow high speed still photographs and video tape to be taken of the air-water flow field. Flow field images are digitized and stored in a Macintosh 2ci computer using a frame grabber board. Local grey levels are related to liquid thickness in the flow channel using a calibration fixture. Image processing shareware is used to calculate the spatially averaged liquid thickness from the image of the flow field. Time averaged spatial liquid distributions are calculated using image calculation algorithms. The spatially averaged liquid distribution is calculated from the time averaged spatial liquid distribution to formulate the combined temporally and spatially averaged fraction values. The temporally and spatially averaged liquid fractions measured using this technique compare well to those predicted from pressure gradient measurements at zero superficial liquid velocity

  20. Nitric oxide in exhaled and aspirated nasal air as an objective measure of human response to indoor air pollution

    DEFF Research Database (Denmark)

    Kolarik, Barbara; Lagercrantz, L.; Sundell, Jan

    2009-01-01

    The concentration of nitric oxide (NO) in exhaled and aspirated nasal air was used to objectively assess human response to indoor air pollutants in a climate chamber exposure experiment. The concentration of NO was measured before exposure, after 2, and 4.5 h of exposure, using a chemiluminescence...... by the exposures. The results may indicate an association between polluted indoor air and subclinical inflammation.Measurement of nitric oxide in exhaled air is a possible objective marker of subclinical inflammation in healthy adults....... NO analyzer. Sixteen healthy female subjects were exposed to two indoor air pollutants and to a clean reference condition for 4.5 h. Subjective assessments of the environment were obtained by questionnaires. After exposure (4.5 h) to the two polluted conditions a small increase in NO concentration in exhaled...

  1. Bromine measurements in ozone depleted air over the Arctic Ocean

    Directory of Open Access Journals (Sweden)

    J. A. Neuman

    2010-07-01

    Full Text Available In situ measurements of ozone, photochemically active bromine compounds, and other trace gases over the Arctic Ocean in April 2008 are used to examine the chemistry and geographical extent of ozone depletion in the arctic marine boundary layer (MBL. Data were obtained from the NOAA WP-3D aircraft during the Aerosol, Radiation, and Cloud Processes affecting Arctic Climate (ARCPAC study and the NASA DC-8 aircraft during the Arctic Research of the Composition of the Troposphere from Aircraft and Satellites (ARCTAS study. Fast (1 s and sensitive (detection limits at the low pptv level measurements of BrCl and BrO were obtained from three different chemical ionization mass spectrometer (CIMS instruments, and soluble bromide was measured with a mist chamber. The CIMS instruments also detected Br2. Subsequent laboratory studies showed that HOBr rapidly converts to Br2 on the Teflon instrument inlets. This detected Br2 is identified as active bromine and represents a lower limit of the sum HOBr + Br2. The measured active bromine is shown to likely be HOBr during daytime flights in the arctic. In the MBL over the Arctic Ocean, soluble bromide and active bromine were consistently elevated and ozone was depleted. Ozone depletion and active bromine enhancement were confined to the MBL that was capped by a temperature inversion at 200–500 m altitude. In ozone-depleted air, BrO rarely exceeded 10 pptv and was always substantially lower than soluble bromide that was as high as 40 pptv. BrCl was rarely enhanced above the 2 pptv detection limit, either in the MBL, over Alaska, or in the arctic free troposphere.

  2. Measurements of air pollution from a Danish highway

    Energy Technology Data Exchange (ETDEWEB)

    Ellermann, T.; Solvang Jensen, S.; Ketzel, M.; Loefstroem, P. Massling, A.

    2009-07-15

    This report presents the results from a measurement campaign carried out at the Holbaek Highway during 2008. The objective of the campaign was to determine the emission factors for PM{sub 2.5} and PM{sub 10} due to highway traffic. The campaign included measurements of NO{sub x}, NO, NO{sub 2}, TEOM PM{sub 2.5}, TEOM PM{sub 10}, O{sub 3}, particle size distribution and local meteorology. The emission factors for PM{sub 2.5} and PM{sub 10} were determined to 45 and 155 mg/(vehicle km), respectively. This is comparable to the emission factors previously determined for H. C. Andersens Boulevard in Copenhagen and somewhat higher than found at Jagtvej, Copenhagen. (author)

  3. Hazard Assessment of Chemical Air Contaminants Measured in Residences

    Energy Technology Data Exchange (ETDEWEB)

    Logue, J.M.; McKone, T.E.; Sherman, M. H.; Singer, B.C.

    2010-05-10

    Identifying air pollutants that pose a potential hazard indoors can facilitate exposure mitigation. In this study, we compiled summary results from 77 published studies reporting measurements of chemical pollutants in residences in the United States and in countries with similar lifestyles. These data were used to calculate representative mid-range and upper bound concentrations relevant to chronic exposures for 267 pollutants and representative peak concentrations relevant to acute exposures for 5 activity-associated pollutants. Representative concentrations are compared to available chronic and acute health standards for 97 pollutants. Fifteen pollutants appear to exceed chronic health standards in a large fraction of homes. Nine other pollutants are identified as potential chronic health hazards in a substantial minority of homes and an additional nine are identified as potential hazards in a very small percentage of homes. Nine pollutants are identified as priority hazards based on the robustness of measured concentration data and the fraction of residences that appear to be impacted: acetaldehyde; acrolein; benzene; 1,3-butadiene; 1,4-dichlorobenzene; formaldehyde; naphthalene; nitrogen dioxide; and PM{sub 2.5}. Activity-based emissions are shown to pose potential acute health hazards for PM{sub 2.5}, formaldehyde, CO, chloroform, and NO{sub 2}.

  4. Unrestricted release measurements with ambient air ionization monitors

    International Nuclear Information System (INIS)

    MacArthur, D.; Gunn, R.; Dockray, T.; Luff, C.

    1999-01-01

    Radiation monitoring systems based on the long-range alpha detection (LRAD) technique, such as the BNFL Instruments IonSens trademark, provide a single contamination measurement for an entire object rather than the more familiar individual readings for smaller surface areas. The LRAD technique relies on the ionization of ambient air molecules by alpha particles, and the subsequent detection of these ions, rather than direct detection of the alpha particles themselves. A single monitor can detect all of the ions produced over a large object and report a total contamination level for the entire surface of that object. However, both the unrestricted release limits specified in USDOE Order 5400.5 (and similar documents in other countries), and the definitions of radioactive waste categories, are stated in terms of contamination per area. Thus, conversion is required between the total effective contamination as measured by the LRAD-based detector and the allowable release limits. In addition, since the release limits were not written assuming an averaging detector system, the method chosen to average the assumed contamination over the object can have a significant impact on the effective sensitivity of the detector

  5. Mobile system for on-road measurements of air pollutants

    Science.gov (United States)

    Katulski, Ryszard J.; Namieśnik, Jacek; Sadowski, Jarosław; Stefański, Jacek; Szymańska, Krystyna; Wardencki, Waldemar

    2010-04-01

    The paper presents a prototype of a mobile monitoring system for measuring the levels of the main traffic air pollutants (C6H6, NO2, NOx, CO, and CO2,) in cities. The novelty of the proposed system lies in the fact that it can be utilized to monitor emissions from urban traffic along roads and areas where traditional monitoring stations cannot be placed. In the proposed system, the monitoring device can be mounted on any moving vehicle (such as a car, bus, or truck) rather than be attached to a dedicated van, as most systems of this kind found in literature are. Analyzers used in this system are small portable structures that contain an electronic instrument to measure, record, and transmit relevant data on concentrations of the pollutants to a website. The model outcome for carbon monoxide obtained in functional tests in real conditions is also presented here. Data on temporal changes of carbon monoxide concentration are compared against meteorological parameters and speed of the vehicle. Spatial interpolation techniques are applied to obtain a nonplanar visualization of carbon monoxide and benzene concentrations in the main arteries of a city.

  6. Advancing a smart air cushion system for preventing pressure ulcers using projection Moiré for large deformation measurements

    Science.gov (United States)

    Cheng, Sheng-Lin; Tsai, Tsung-Heng; Lee, Carina Jean-Tien; Hsu, Yu-Hsiang; Lee, Chih-Kung

    2016-03-01

    A pressure ulcer is one of the most important concerns for wheelchair bound patients with spinal cord injuries. A pressure ulcer is a localized injury near the buttocks that bear ischial tuberosity oppression over a long period of time. Due to elevated compression to blood vessels, the surrounding tissues suffer from a lack of oxygen and nutrition. The ulcers eventually lead to skin damage followed by tissue necrosis. The current medical strategy is to minimize the occurrence of pressure ulcers by regularly helping patients change their posture. However, these methods do not always work effectively or well. As a solution to fundamentally prevent pressure ulcers, a smart air cushion system was developed to detect and control pressure actively. The air cushion works by automatically adjusting a patient's sitting posture to effectively relieve the buttock pressure. To analyze the correlation between the dynamic pressure profiles of an air cell with a patient's weight, a projection Moiré system was adopted to measure the deformation of an air cell and its associated stress distribution. Combining a full-field deformation imaging with air pressure measured within an air cell, the patient's weight and the stress distribution can be simultaneously obtained. By integrating a full-field optical metrology with a time varying pressure sensor output coupled with different active air control algorithms for various designs, we can tailor the ratio of the air cells. Our preliminary data suggests that this newly developed smart air cushion has the potential to selectively reduce localized compression on the tissues at the buttocks. Furthermore, it can take a patient's weight which is an additional benefit so that medical personnel can reference it to prescribe the correct drug dosages.

  7. Measurement of reactivity effect caused by nonuniform fuel distribution

    International Nuclear Information System (INIS)

    Yamane, Yoshihiro; Hirano, Yasushi; Yasui, Hazime; Nishina, Kojiro; Shiroya, Seiji

    1991-01-01

    A reactivity effect due to a spatial variation of nuclear fuel concentration is an important problem in a reprocessing plant. To estimate this reactivity effect theoretically, the ''Goertzel's necessary condition, and th Fuel Importance'' theory have been proposed. In order to verify these theories, we have performed systematic measurements of reactivity effect due to the nonuniformity in the fuel distribution within the Kyoto University Critical Assembly. Neutron flux distribution and Fuel Importance distribution were also determined. A nonuniform assembly whose fuel concentration in the center region was 40% higher than the uniform one was found to have an excess reactivity of 0.3%Δk/k, with the same total uranium mass for which the uniform assembly was just critical. Moreover, its spatial distribution of thermal neutron flux and of Fuel Importance were more flat than those of the uniform assembly, as expected by the Goertzel's condition and the Fuel Importance theory. (Author)

  8. Measurement of intensity distribution of CSR in LEBRA PXR beamline

    International Nuclear Information System (INIS)

    Nakao, Keisuke; Sakai, Takeshi; Hayakawa, Ken; Tanaka, Toshinari; Hayakawa, Yasushi; Nogami, Kyoko; Inagaki, Manabu; Sei, Norihiro

    2014-01-01

    Last year, the intensity of Coherent Synchrotron Radiation (CSR) in LEBRA PXR beamline was measured. As a result, it turned out that the intensity of CSR was stronger than anticipation. It is suggested that Coherent Edge Radiation (CER) is mixed with CSR. Then, in order to confirm whether CER is contained, the intensity distribution of CSR was measured. The result of the experiment is reported in this paper. (author)

  9. A new kind of droplet space distribution measuring method

    International Nuclear Information System (INIS)

    Ma Chao; Bo Hanliang

    2012-01-01

    A new kind of droplet space distribution measuring technique was introduced mainly, and the experimental device which was designed for the measuring the space distribution and traces of the flying film droplet produced by the bubble breaking up near the free surface of the water. This experiment was designed with a kind of water-sensitivity test paper (rice paper) which could record the position and size of the colored scattering droplets precisely. The rice papers were rolled into cylinders with different diameters by using tools. The bubbles broke up exactly in the center of the cylinder, and the space distribution and the traces of the droplets would be received by analysing all the positions of the droplets produced by the same size bubble on the rice papers. (authors)

  10. Determination and optimization of spatial samples for distributed measurements.

    Energy Technology Data Exchange (ETDEWEB)

    Huo, Xiaoming (Georgia Institute of Technology, Atlanta, GA); Tran, Hy D.; Shilling, Katherine Meghan; Kim, Heeyong (Georgia Institute of Technology, Atlanta, GA)

    2010-10-01

    There are no accepted standards for determining how many measurements to take during part inspection or where to take them, or for assessing confidence in the evaluation of acceptance based on these measurements. The goal of this work was to develop a standard method for determining the number of measurements, together with the spatial distribution of measurements and the associated risks for false acceptance and false rejection. Two paths have been taken to create a standard method for selecting sampling points. A wavelet-based model has been developed to select measurement points and to determine confidence in the measurement after the points are taken. An adaptive sampling strategy has been studied to determine implementation feasibility on commercial measurement equipment. Results using both real and simulated data are presented for each of the paths.

  11. Air-Sea exchange of biogenic volatile organic compounds and the impact on aerosol particle size distributions

    Science.gov (United States)

    Kim, Michelle J.; Novak, Gordon A.; Zoerb, Matthew C.; Yang, Mingxi; Blomquist, Byron W.; Huebert, Barry J.; Cappa, Christopher D.; Bertram, Timothy H.

    2017-04-01

    We report simultaneous, underway eddy covariance measurements of the vertical flux of isoprene, total monoterpenes, and dimethyl sulfide (DMS) over the Northern Atlantic Ocean during fall. Mean isoprene and monoterpene sea-to-air vertical fluxes were significantly lower than mean DMS fluxes. While rare, intense monoterpene sea-to-air fluxes were observed, coincident with elevated monoterpene mixing ratios. A statistically significant correlation between isoprene vertical flux and short wave radiation was not observed, suggesting that photochemical processes in the surface microlayer did not enhance isoprene emissions in this study region. Calculations of secondary organic aerosol production rates (PSOA) for mean isoprene and monoterpene emission rates sampled here indicate that PSOA is on average <0.1 μg m-3 d-1. Despite modest PSOA, low particle number concentrations permit a sizable role for condensational growth of monoterpene oxidation products in altering particle size distributions and the concentration of cloud condensation nuclei during episodic monoterpene emission events from the ocean.

  12. Distribution Line Parameter Estimation Under Consideration of Measurement Tolerances

    DEFF Research Database (Denmark)

    Prostejovsky, Alexander; Gehrke, Oliver; Kosek, Anna Magdalena

    2016-01-01

    conductance that the absolute compensated error is −1.05% and −1.07% for both representations, as opposed to the expected uncompensated error of −79.68%. Identification of a laboratory distribution line using real measurement data grid yields a deviation of 6.75% and 4.00%, respectively, from a calculation...

  13. Measuring Geographic Distribution of Economic Activity in Nigeria ...

    African Journals Online (AJOL)

    Measuring Geographic Distribution of Economic Activity in Nigeria Using Gross Domestic Product. ... and environmental factors in planning. There is need for adequate understanding of spatial pattern and centrographic analysis of economic activity to support evidence based economic and regional development policies.

  14. The measurements of thermal neutron flux distribution in a paraffin

    Indian Academy of Sciences (India)

    The term `thermal flux' implies a Maxwellian distribution of velocity and energy corresponding to the most probable velocity of 2200 ms-1 at 293.4 K. In order to measure the thermal neutron flux density, the foil activation method was used. Thermal neutron flux determination in paraffin phantom by counting the emitted rays of ...

  15. Device for measuring neutron-flux distribution density

    International Nuclear Information System (INIS)

    Rozenbljum, N.D.; Mitelman, M.G.; Kononovich, A.A.; Kirsanov, V.S.; Zagadkin, V.A.

    1977-01-01

    An arrangement is described for measuring the distribution of neutron flux density over the height of a nuclear reactor core and which may be used for monitoring energy release or for detecting deviations of neutron flux from an optimal level so that subsequent balance can be achieved. It avoids mutual interference of detectors. Full constructional details are given. (UK)

  16. Recoil range distribution measurement in 20Ne + 181Ta reaction

    International Nuclear Information System (INIS)

    Tripathi, R.; Sudarshan, K.; Goswami, A.; Guin, R.; Reddy, A.V.R.

    2005-01-01

    In order to investigate linear momentum transfer in various transfer channels in 20 Ne + 181 Ta, recoil range distribution measurements have been carried out at E lab = 180 MeV, populating significant number of l-waves above l crit

  17. Bidirectional reflectance distribution function measurements and analysis of retroreflective materials.

    Science.gov (United States)

    Belcour, Laurent; Pacanowski, Romain; Delahaie, Marion; Laville-Geay, Aude; Eupherte, Laure

    2014-12-01

    We compare the performance of various analytical retroreflecting bidirectional reflectance distribution function (BRDF) models to assess how they reproduce accurately measured data of retroreflecting materials. We introduce a new parametrization, the back vector parametrization, to analyze retroreflecting data, and we show that this parametrization better preserves the isotropy of data. Furthermore, we update existing BRDF models to improve the representation of retroreflective data.

  18. Laboratory Evaluation of Air Flow Measurement Methods for Residential HVAC Returns

    Energy Technology Data Exchange (ETDEWEB)

    Walker, Iain; Stratton, Chris

    2015-07-01

    This project improved the accuracy of air flow measurements used in commissioning California heating and air conditioning systems in Title 24 (Building and Appliance Efficiency Standards), thereby improving system performance and efficiency of California residences. The research team at Lawrence Berkeley National Laboratory addressed the issue that typical tools used by contractors in the field to test air flows may not be accurate enough to measure return flows used in Title 24 applications. The team developed guidance on performance of current diagnostics as well as a draft test method for use in future evaluations. The series of tests performed measured air flow using a range of techniques and devices. The measured air flows were compared to reference air flow measurements using inline air flow meters built into the test apparatus. The experimental results showed that some devices had reasonable results (typical errors of 5 percent or less) but others had much bigger errors (up to 25 percent).

  19. Improved technique for measuring the size distribution of black carbon particles in rainwater and snow samples

    Science.gov (United States)

    Mori, T.; Moteki, N.; Ohata, S.; Koike, M.; Azuma, K. G.; Miyazaki, Y.; Kondo, Y.

    2015-12-01

    Black carbon (BC) is the strongest contributor to sunlight absorption among atmospheric aerosols. Quantitative understanding of wet deposition of BC, which strongly affects the spatial distribution of BC, is important to improve our understandings on climate change. We have devised a technique for measuring the masses of individual BC particles in rainwater and snow samples, as a combination of a nebulizer and a single-particle soot photometer (SP2) (Ohata et al. 2011, 2013; Schwarz et al. 2012; Mori et al. 2014). We show two important improvements in this technique: 1)We have extended the upper limit of detectable BC particle diameter from 0.9 μm to about 4.0 μm by modifying the photodetector for measuring the laser-induced incandescence signal. 2)We introduced a pneumatic nebulizer Marin-5 (Cetac Technologies Inc., Omaha, NE, USA) and experimentally confirmed its high extraction efficiency (~50%) independent of particle diameter up to 2.0 μm. Using our improved system, we simultaneously measured the size distribution of BC particles in air and rainwater in Tokyo. We observed that the size distribution of BC in rainwater was larger than that in air, indicating that large BC particles were effectively removed by precipitation. We also observed BC particles with diameters larger than 1.0 μm, indicating that further studies of wet deposition of BC will require the use of the modified SP2.

  20. Radial Distribution of the Nanosecond Dielectric Barrier Discharge Current in Atmospheric-Pressure Air

    Science.gov (United States)

    Malashin, M. V.; Moshkunov, S. I.; Khomich, V. Yu.; Shershunova, E. A.

    2018-01-01

    Experimental results on the radial distribution of the nanosecond dielectric barrier discharge (DBD) current in flat millimeter air gaps under atmospheric pressure and natural humidity of 40-60% at a voltage rise rate at the electrodes of 250 V/ns are presented. The time delay of the appearance of discharge currents was observed to increase from the center to the periphery of the air gap at discharge gap heights above 3 mm, which correlated with the appearance of constricted channels against the background of the volume DBD plasma. Based on the criterion of the avalanche-streamer transition, it is found out that the development of a nanosecond DBD in air gaps of 1-3 mm occurs by the streamer mechanism.

  1. MEASUREMENT OPTIMALIZATION OF ZAKAT DISTRIBUTION AT LEMBAGA AMIL ZAKAT USING VARIABLE MEASUREMENT OF ECONOMY

    Directory of Open Access Journals (Sweden)

    Marissa Haque

    2016-09-01

    Full Text Available The aim of this research conducted is to optimalize the zakat distribution using economy variabel measurement. Design/Metodology. The Quantitative Research Method is used to analyze financial data, with Optimalize Model as Z variable design, Measurement of Economy as Y variable and Objective Output as X variable, using AMOS program and SEM as tool analysis to confirm that the model can be used as a measurement tool. Research result. Using some indicators to analyze every variable, obtaining output and objective result, influence optimalization of measurement of economy. Conclusion. The measurement of optimalization of zakat distribution using measurement of economy variable, with independent variable/output exogenous and objective, can be used as a model to measure Lembaga Amil Zakat performance. Furthermore, this research need to have some indicators’ development especially in the area of objective variable. Key words:   Output, Objective, Measurement of Economy, Distribution Optimalization, Zakat JEL Classification: D64

  2. THE DISTRIBUTION OF CHLORPYRIFOS FOLLOWING A CRACK AND CREVICE TYPE APPLICATION IN THE U.S. EPA INDOOR AIR QUALITY RESEARCH HOUSE

    Science.gov (United States)

    A study was conducted in the U.S. EPA Indoor Air Quality Research House to determine the spatial and temporal distribution of chlorpyrifos following a professional crack and crevice application in the kitchen. Following the application, measurements were made in the kitchen, de...

  3. THE DISTRIBUTION OF CHLORPYRIFOS FOLLOWING A CRACK AND CREVICE TYPE APPLICATION IN THE U.S. EPA INDOOR AIR QUALITY TEST HOUSE

    Science.gov (United States)

    A study was conducted in the U.S. EPA Indoor Air Quality Test House to determine the spatial and temporal distribution of chlorpyrifos following a professional crack and crevice application in the kitchen. Following the application, measurements were made in the kitchen, den a...

  4. Measurement of the proton-air cross-section at $\\sqrt{s}=57$ TeV with the Pierre Auger Observatory

    Energy Technology Data Exchange (ETDEWEB)

    Collaboration, Auger

    2012-08-01

    We report a measurement of the proton-air cross section for particle production at the center-of-mass energy per nucleon of 57 TeV. This is derived from the distribution of the depths of shower maxima observed with the Pierre Auger Observatory: systematic uncertainties are studied in detail. Analyzing the tail of the distribution of the shower maxima, a proton-air cross section of [505 {+-} 22(stat){sub -36}{sup +28}(syst)] mb is found.

  5. Advection-diffusion model for the simulation of air pollution distribution from a point source emission

    Science.gov (United States)

    Ulfah, S.; Awalludin, S. A.; Wahidin

    2018-01-01

    Advection-diffusion model is one of the mathematical models, which can be used to understand the distribution of air pollutant in the atmosphere. It uses the 2D advection-diffusion model with time-dependent to simulate air pollution distribution in order to find out whether the pollutants are more concentrated at ground level or near the source of emission under particular atmospheric conditions such as stable, unstable, and neutral conditions. Wind profile, eddy diffusivity, and temperature are considered in the model as parameters. The model is solved by using explicit finite difference method, which is then visualized by a computer program developed using Lazarus programming software. The results show that the atmospheric conditions alone influencing the level of concentration of pollutants is not conclusive as the parameters in the model have their own effect on each atmospheric condition.

  6. Some important results from the air pollution distribution model STACKS (1988-1992)

    International Nuclear Information System (INIS)

    Erbrink, J.J.

    1993-01-01

    Attention is paid to the results of the study on the distribution of air pollutants by high chimney-stacks of electric power plants. An important product of the study is the integrated distribution model STACKS (Short Term Air-pollutant Concentrations Kema modelling System). The improvements and the extensions of STACKS are described in relation to the National Model, which has been used to estimate the environmental effects of individual chimney-stacks. The National Model shows unacceptable variations for high pollutant sources. Based on the results of STACKS revision of the National model has been taken into consideration. By means of the revised National Model a more realistic estimation of the environmental effects of electric power plants can be carried out

  7. Distributions of freak wave heights measured in the North Sea

    International Nuclear Information System (INIS)

    Stansell, P.

    2004-01-01

    We present a statistical analysis of some of the largest waves occurring during 793 h of surface elevation measurements collected during 14 severe storms in the North Sea. This data contains 104 freak waves. It is found that the probability of occurrence of freak waves is only weekly dependent on the significant wave height, significant wave steepness and spectral bandwidth. The probability does show a slightly stronger dependency on the skew and kurtosis of the surface elevation data, but on removing the contribution to these measures from the presence of the freakwaves themselves, this dependency largely disappears. Distributions of extreme waves are modelled by fitting Generalised Pareto distributions, and extreme value distributions and return periods are given for freak waves in terms of the empirical fitted parameters. It is shown by comparison with these fits that both the Rayleigh distribution and the fit of Nerzic and Prevosto severely under-predict the probability of occurrence of extreme waves. For the most extreme freak wave in our data, the Rayleigh distribution over-predicts the return period by about 300 times when compared to the fitted model. (author)

  8. Thermal decay in underfloor air distribution (UFAD) systems: Fundamentals and influence on system performance

    International Nuclear Information System (INIS)

    Lee, Kwang Ho; Schiavon, Stefano; Bauman, Fred; Webster, Tom

    2012-01-01

    Graphical abstract: Surface heat transfer breakdown for an underfloor air distribution (UFAD) system supply plenum. Highlights: ► Thermal decay of a UFAD system is considerable (annual median = 3.7 K). ► Thermal decay is driven by heat transfer through both the concrete slab and the raised floor. ► Thermal decay may lead to higher airflow rates and increased fan and chiller energy consumption. -- Abstract: Underfloor air distribution (UFAD) is a mechanical ventilation strategy in which the conditioned air is primarily delivered to the zone from a pressurized plenum through floor mounted diffusers. Compared to conventional overhead (OH) mixing systems, UFAD has several potential advantages, such as improved thermal comfort and indoor air quality (IAQ), layout flexibility, reduced life cycle costs and improved energy efficiency in suitable climates. In ducted OH systems designers have reasonably accurate control of the diffuser supply temperature, while in UFAD this temperature is difficult to predict due to the heat gain of the conditioned air in the supply plenum. The increase in temperature between the air entering the plenum and air leaving through a diffuser is known as thermal decay. In this study, the detailed whole-building energy simulation program, EnergyPlus, was used to explain the fundamentals of thermal decay, to investigate its influence on energy consumption and to study the parameters that affect thermal decay. It turns out that the temperature rise is considerable (annual median = 3.7 K, with 50% of the values between 2.4 and 4.7 K based on annual simulations). Compared to an idealized simulated UFAD case with no thermal decay, elevated diffuser air temperatures can lead to higher supply airflow rate and increased fan and chiller energy consumption. The thermal decay in summer is higher than in winter and it also depends on the climate. The ground floor with a slab on grade has less temperature rise compared to middle and top floors. An

  9. NASA Langley and NLR Research of Distributed Air/Ground Traffic Management

    Science.gov (United States)

    Ballin, Mark G.; Hoekstra, Jacco M.; Wing, David J.; Lohr, Gary W.

    2002-01-01

    Distributed Air/Ground Traffic Management (DAG-TM) is a concept of future air traffic operations that proposes to distribute information, decision-making authority, and responsibility among flight crews, the air traffic service provider, and aeronautical operational control organizations. This paper provides an overview and status of DAG-TM research at NASA Langley Research Center and the National Aerospace Laboratory of The Netherlands. Specific objectives of the research are to evaluate the technical and operational feasibility of the autonomous airborne component of DAG-TM, which is founded on the operational paradigm of free flight. The paper includes an overview of research approaches, the airborne technologies under development, and a summary of experimental investigations and findings to date. Although research is not yet complete, these findings indicate that free flight is feasible and will significantly enhance system capacity and safety. While free flight cannot alone resolve the complex issues faced by those modernizing the global airspace, it should be considered an essential part of a comprehensive air traffic management modernization activity.

  10. Imaging and Measuring Electron Beam Dose Distributions Using Holographic Interferometry

    DEFF Research Database (Denmark)

    Miller, Arne; McLaughlin, W. L.

    1975-01-01

    Holographic interferometry was used to image and measure ionizing radiation depth-dose and isodose distributions in transparent liquids. Both broad and narrowly collimated electron beams from accelerators (2–10 MeV) provided short irradiation times of 30 ns to 0.6 s. Holographic images...... and measurements of absorbed dose distributions were achieved in liquids of various densities and thermal properties and in water layers thinner than the electron range and with backings of materials of various densities and atomic numbers. The lowest detectable dose in some liquids was of the order of a few k......Rad. The precision limits of the measurement of dose were found to be ±4%. The procedure was simple and the holographic equipment stable and compact, thus allowing experimentation under routine laboratory conditions and limited space....

  11. Frequency distribution analysis of the long-lived beta-activity of air dust

    International Nuclear Information System (INIS)

    Bunzl, K.; Hoetzl, H.; Winkler, R.

    1977-01-01

    In order to compare the average annual beta activities of air dust a frequency distribution analysis of data has been carried out in order to select a representative quantity for the average value of the data group. It was found that the data to be analysed were consistent with a log-normal frequency distribution and therefore calculations were made of, as the representative average, the median of the beta activity of each year as the antilog of the arithmetric mean of the logarithms, log x, of the analytical values x. The 95% confidence limits were also obtained. The quantities thus calculated are summarized in tabular form. (U.K.)

  12. Probabilistic reconstruction of internal exposure for nuclear power plant workers using air concentration measurements

    International Nuclear Information System (INIS)

    Linkov, I.; Burmistrov, D.

    2000-01-01

    Committed Effective Dose Equivalent (CEDE) for Mr. X. The total internal intake was calculated using Monte-Carlo simulations and then translated to dose using dose conversion factor. The results of the analysis reveal a broad distribution in dose estimates. The resulting dose distribution is significantly skewed to the high doses. The mean dose estimate is significantly different from the median dose. Median doses, which are often required for litigation in similar cases (to estimate if somebody, more likely than not, has received a dose above specified limit), should therefore be estimated using probabilistic techniques since using the mean for deterministic estimates may lead to erroneous conclusions for non-symmetric data distributions. Sensitivity analysis was conducted to determine which of the input parameters contributed most to the uncertainty in internal dose estimates. The spatial and temporal variations in air concentration measurements were found to be among the most significant contributors. Internal dose estimates that use individual air surveys supported by bioassay and whole-body counting data are desirable for internal dose reconstruction. (author)

  13. [Airborne Fungal Aerosol Concentration and Distribution Characteristics in Air- Conditioned Wards].

    Science.gov (United States)

    Zhang, Hua-ling; Feng, He-hua; Fang, Zi-liang; Wang, Ben-dong; Li, Dan

    2015-04-01

    The effects of airborne fungus on human health in the hospital environment are related to not only their genera and concentrations, but also their particle sizes and distribution characteristics. Moreover, the mechanisms of aerosols with different particle sizes on human health are different. Fungal samples were obtained in medicine wards of Chongqing using a six-stage sampler. The airborne fungal concentrations, genera and size distributions of all the sampling wards were investigated and identified in detail. Results showed that airborne fungal concentrations were not correlated to the diseases or personnel density, but were related to seasons, temperature, and relative humidity. The size distribution rule had roughly the same for testing wards in winter and summer. The size distributions were not related with diseases and seasons, the percentage of airborne fungal concentrations increased gradually from stage I to stage III, and then decreased dramatically from stage V to stage VI, in general, the size of airborne fungi was a normal distribution. There was no markedly difference for median diameter of airborne fungi which was less 3.19 μm in these wards. There were similar dominant genera in all wards. They were Aspergillus spp, Penicillium spp and Alternaria spp. Therefore, attention should be paid to improve the filtration efficiency of particle size of 1.1-4.7 μm for air conditioning system of wards. It also should be targeted to choose appropriate antibacterial methods and equipment for daily hygiene and air conditioning system operation management.

  14. Experimental measurements of spatial dose distributions in radiosurgery treatments

    International Nuclear Information System (INIS)

    Avila-Rodriguez, M. A.; Rodriguez-Villafuerte, M.; Diaz-Perches, R.; Perez-Pastenes, M. A.

    2001-01-01

    The measurement of stereotactic radiosurgery dose distributions requires an integrating, high-resolution dosimeter capable of providing a spatial map of absorbed dose. This paper describes the use of a commercial radiochromic dye film (GafChromic MD-55-2) to measure radiosurgery dose distributions with 6 MV X-rays in a head phantom. The response of the MD-55-2 was evaluated by digitizing and analyzing the films with conventional computer systems. Radiosurgery dose distributions were measured using the radiochromic film in a spherical acrylic phantom of 16 cm diameter undergoing a typical SRS treatment as a patient, and were compared with dose distributions provided by the treatment planning system. The comparison lead to mean radial differences of ±0.6 mm, ±0.9 mm, ±1.3 mm, ±1.9 mm, and ±2.8 mm, for the 80, 60, 50, 40, and 30% isodose curves, respectively. It is concluded that the radiochromic film is a convenient and useful tool for radiosurgery treatment planning validation

  15. Measurements of the angular distribution of diffuse irradiance

    DEFF Research Database (Denmark)

    Andersen, Elsa; Nielsen, Kristian Pagh; Dragsted, Janne

    2015-01-01

    Advanced solar resource assessment and forecasting is necessary for optimal solar energy utilization. In order to investigate the short-term resource variability, for instance caused by clouds it is necessary to investigate how clouds affect the solar irradiance, including the angular distribution...... of the solar irradiance. The investigation is part of the Danish contribution to the taskforce 46 within the International Energy Agency and financed by the Danish Energy Agency. The investigation focuses on the distribution of the diffuse solar irradiance and is based on horizontal measurements of the solar...

  16. Air tightness measurements in older Danish single-family houses

    DEFF Research Database (Denmark)

    Mortensen, Lone Hedegaard; Bergsøe, Niels Christian

    2017-01-01

    of the building envelope of older buildings despite the fact that the air tightness has a major influence on the energy use. In connection with renovation of the Danish building stock, the coming years will see increased focus on the air tightness of the building envelope like in other countries. This paper...

  17. Demonstrations of Magnetic Phenomena: Measuring the Air Permeability Using Tablets

    Science.gov (United States)

    Lara, V. O. M.; Amaral, D. F.; Faria, D.; Vieira, L. P.

    2014-01-01

    We use a tablet to experimentally determine the dependencies of the magnetic field (B) on the electrical current and the axial distance from a coil (z). Our data shows good precision on the inverse cubic dependence of the magnetic field on the axial distance, B?z[superscript -3]. We obtain the value of air permeability µ[subscript air] with good…

  18. International conventions on air pollution abatement. Implementation measures

    International Nuclear Information System (INIS)

    Adler, S.; Groza, L.

    1996-01-01

    The environmental protection, the pollution reduction, their positive direct and indirect effects, the energy efficiency increase in using fossil fuels have an important role on the environmental and energy policies, as well as on the long-term planning. The report presents, under the new legislative context, the general frame from the implementation of concrete actions to fulfill the commitments contained in different environmental conventions, in which Romania is or intends to be a part. In this context it is presented the national approach for the implementation of two conventions: the United Nations Framework Convention on Climate Change and the Long-Range Transboundary Air Pollution, this under the United Nations Economic Commission for Europe. The report presents the necessary measures to reduce the emissions of carbon, sulfur and nitrogen oxides taking into account the process of the Romanian integration in the European structure as well as the dynamic of the economic reform. Romania is aware that the necessary environmental activities (research, design, environmental investments etc.) must be financed from internal resources, the own resources of the polluting economic units, the central and local budgets. (author). 7 refs

  19. Comparisons of Air Radiation Model with Shock Tube Measurements

    Science.gov (United States)

    Bose, Deepak; McCorkle, Evan; Bogdanoff, David W.; Allen, Gary A., Jr.

    2009-01-01

    This paper presents an assessment of the predictive capability of shock layer radiation model appropriate for NASA s Orion Crew Exploration Vehicle lunar return entry. A detailed set of spectrally resolved radiation intensity comparisons are made with recently conducted tests in the Electric Arc Shock Tube (EAST) facility at NASA Ames Research Center. The spectral range spanned from vacuum ultraviolet wavelength of 115 nm to infrared wavelength of 1400 nm. The analysis is done for 9.5-10.5 km/s shock passing through room temperature synthetic air at 0.2, 0.3 and 0.7 Torr. The comparisons between model and measurements show discrepancies in the level of background continuum radiation and intensities of atomic lines. Impurities in the EAST facility in the form of carbon bearing species are also modeled to estimate the level of contaminants and their impact on the comparisons. The discrepancies, although large is some cases, exhibit order and consistency. A set of tests and analyses improvements are proposed as forward work plan in order to confirm or reject various proposed reasons for the observed discrepancies.

  20. Continuous scanning of the mobility and size distribution of charged clusters and nanometer particles in atmospheric air and the Balanced Scanning Mobility Analyzer BSMA

    Science.gov (United States)

    Tammet, H.

    2006-12-01

    Measuring of charged nanometer particles in atmospheric air is a routine task in research on atmospheric electricity, where these particles are called the atmospheric ions. An aspiration condenser is the most popular instrument for measuring atmospheric ions. Continuous scanning of a mobility distribution is possible when the aspiration condenser is connected as an arm of a balanced bridge. Transfer function of an aspiration condenser is calculated according to the measurements of geometric dimensions, air flow rate, driving voltage, and electric current. The most complicated phase of the calibration is the estimation of the inlet loss of ions due to the Brownian deposition. The available models of ion deposition on the protective inlet screen and the inlet control electrofilter have the uncertainty of about 20%. To keep the uncertainty of measurements low the adsorption should not exceed a few tens of percent. The online conversion of the mobility distribution to the size distribution and a correct reduction of inlet losses are possible when air temperature and pressure are measured simultaneously with the mobility distribution. Two instruments called the Balanced Scanning Mobility Analyzers (BSMA) were manufactured and tested in routine atmospheric measurements. The concentration of atmospheric ions of the size of about a few nanometers is very low and a high air flow rate is required to collect enough of ion current. The air flow of 52 l/s exceeds the air flow in usual aerosol instruments by 2-3 orders of magnitude. The high flow rate reduces the time of ion passage to 60 ms and the heating of air in an analyzer to 0.2 K, which suppresses a possible transformation of ions inside the instrument. The mobility range of the BSMA of 0.032-3.2 cm 2 V - 1 s - 1 is logarithmically uniformly divided into 16 fractions. The size distribution is presented by 12 fractions in the diameter range of 0.4-7.5 nm. The measurement noise of a fraction concentration is typically

  1. The effect of body postures on the distribution of air gap thickness and contact area.

    Science.gov (United States)

    Mert, Emel; Psikuta, Agnes; Bueno, Marie-Ange; Rossi, René M

    2017-02-01

    The heat and mass transfer in clothing is predominantly dependent on the thickness of air layer and the magnitude of contact area between the body and the garment. The air gap thickness and magnitude of the contact area can be affected by the posture of the human body. Therefore, in this study, the distribution of the air gap and the contact area were investigated for different body postures of a flexible manikin. In addition, the effect of the garment fit (regular and loose) and style (t-shirts, sweatpants, jacket and trousers) were analysed for the interaction between the body postures and the garment properties. A flexible manikin was scanned using a three-dimensional (3D) body scanning technique, and the scans were post-processed in dedicated software. The body posture had a strong effect on the air gap thickness and the contact area for regions where the garment had a certain distance from the body. Furthermore, a mathematical model was proposed to estimate the possible heat transfer coefficient for the observed air layers and their change with posture. The outcome of this study can be used to improve the design of the protective and functional garments and predict their effect on the human body.

  2. Measurement of the temperature distribution inside the power cable using distributed temperature system

    Science.gov (United States)

    Jaros, Jakub; Liner, Andrej; Papes, Martin; Vasinek, Vladimir; Mach, Veleslav; Hruby, David; Kajnar, Tomas; Perecar, Frantisek

    2015-01-01

    Nowadays, the power cables are manufactured to fulfill the following condition - the highest allowable temperature of the cable during normal operation and the maximum allowable temperature at short circuit conditions cannot exceed the condition of the maximum allowable internal temperature. The distribution of the electric current through the conductor leads to the increase of the amplitude of electrons in the crystal lattice of the cables material. The consequence of this phenomenon is the increase of friction and the increase of collisions between particles inside the material, which causes the temperature increase of the carrying elements. The temperature increase is unwanted phenomena, because it is causing losses. In extreme cases, the long-term overload leads to the cable damaging or fire. This paper deals with the temperature distribution measurement inside the power cables using distributed temperature system. With cooperation with Kabex company, the tube containing optical fibers was installed into the center of power cables. These fibers, except telecommunications purposes, can be also used as sensors in measurements carrying out with distributed temperature system. These systems use the optical fiber as a sensor and allow the continual measurement of the temperature along the whole cable in real time with spatial resolution 1 m. DTS systems are successfully deployed in temperature measurement applications in industry areas yet. These areas include construction, drainage, hot water etc. Their advantages are low cost, resistance to electromagnetic radiation and the possibility of real time monitoring at the distance of 8 km. The location of the optical fiber in the center of the power cable allows the measurement of internal distribution of the temperature during overloading the cable. This measurement method can be also used for prediction of short-circuit and its exact location.

  3. Radon concentration as an indicator of the indoor air quality: development of an efficient measurement method

    International Nuclear Information System (INIS)

    Roessler, F.A.

    2015-01-01

    Document available in abstract form only. Full text of publication follows: Energy conservation regulation could lead to a reduction of the air exchange rate and also a degradation of the indoor air quality. Present methods for the estimating the indoor air quality can only be implemented with limitations. This paper presents a method that allows the estimation of the indoor air quality under normal conditions by using natural radon as an indicator. With mathematical models, the progression of the air exchange rate is estimated by using the radon concentration. Furthermore, the progression of individual air pollutants is estimated. Through series of experiments in a measurement chamber, the modelling could be verified. (author)

  4. Measuring distributed leadership agency in a hospital context.

    Science.gov (United States)

    Jønsson, Thomas; Unterrainer, Christine; Jeppesen, Hans-Jeppe; Jain, Ajay Kumar

    2016-09-19

    Purpose The purpose of this paper is to develop and validate an instrument that can measure distributed leadership (DL) as employees' active participation in DL tasks. The authors designate this as the distributed leadership agency (DLA). Design/methodology/approach Data were collected throughout all departments and occupational groups at a merged centralized hospital setting in Denmark. A total of 1,774 employees from 24 hospital departments and 16 occupational groups completed our survey. Structural equation model and confirmatory factor analyses were applied to identify appropriate items and a test for measurement invariance, predictive, discriminant and convergent validity, and ANOVAs were applied to analyse group differences in DLA. Findings The identified unidimensional questionnaire consists of seven items, as it is different from, but associated with, empowering leadership, organizational influence, attitude to participation and trust in management. As theoretically predicted, DLA is positively related to self-efficacy, job satisfaction and innovative behaviour. Chief physicians, permanent employees and employee representatives scored higher on the scale than the rest of their respective counterparts. Practical implications The survey offers a method to assess a distribution of leadership agency in hospital organizations. Such assessment may provide a basis for organizational and leadership development. Originality/value The present study provides a reliable and valid quantitative instrument that measures how much employees at all hierarchical levels are involved in concrete leadership activities in the hospital context. Taking a normative perspective the authors could show that DL - measured with the DLA-questionnaire - has positive effects on employees' behaviour.

  5. Effect of cigarette smoke on the measured equivalent volume activity of 222Rn in air

    International Nuclear Information System (INIS)

    Tuckova, S.; Tykva, R.

    1994-01-01

    The effect of cigarette smoke in air on the increase of the measured equivalent volume activity of 222 Rn is demonstrated. After introduction of the smoke from one cigarette into 1 m 3 of air, this value increased up to ten times as shown be the method of sucking air through a filter. (author) 5 refs.; 1 fig

  6. Distribution and air-sea exchange of mercury (Hg in the Yellow Sea

    Directory of Open Access Journals (Sweden)

    Z. J. Ci

    2011-03-01

    Full Text Available The Yellow Sea, surrounded by East China and the Korea Peninsula, is a potentially important receptor for anthropogenic mercury (Hg emissions from East Asia. However, there is little documentation about the distribution and cycle of Hg in this marine system. During the cruise covering the Yellow Sea in July 2010, gaseous elemental mercury (GEM or Hg(0 in the atmosphere, total Hg (THg, reactive Hg (RHg and dissolved gaseous mercury (DGM, largely Hg(0 in the waters were measured aboard the R/V Kexue III. The mean (±SD concentration of GEM over the entire cruise was 2.61 ± 0.50 ng m−3 (range: 1.68 to 4.34 ng m−3, which were generally higher than other open oceans. The spatial distribution of GEM generally reflected a clear gradient with high levels near the coast of East China and low levels in open waters, suggesting the significant atmospheric Hg outflow from East China. The mean concentration of THg in the surface waters was 1.69 ± 0.35 ng l−1 and the RHg accounted for a considerable fraction of THg (RHg: 1.08 ± 0.28 ng l−1, %RHg/THg = 63.9%. The mean concentration of DGM in the surface waters was 63.9 ± 13.7 pg l−1 and always suggested the supersaturation of Hg(0 in the surface waters with respect to Hg(0 in the atmosphere (the degree of saturation: 7.8 ± 2.3 with a range of 3.6–14.0. The mean Hg(0 flux at the air-sea interface was estimated to be 18.3 ± 11.8 ng m−2 h−1 based on a two-layer exchange model. The high wind speed and DGM levels induced the extremely high Hg(0 emission rates. Measurements at three stations showed no clear vertical patterns of DGM, RHg and THg in the water column. Overall, the elevated Hg levels in the Yellow Sea compared with other open oceans suggested that the human activity has influenced the oceanic Hg cycle downwind of East Asia.

  7. Radioactive Aerosol Size Distribution Measured in Nuclear Workplaces

    International Nuclear Information System (INIS)

    Kravchik, T.; Oved, S.; German, U.

    2002-01-01

    Inhalation is the main route for internal exposure of workers to radioactive aerosols in the nuclear industry.Aerosol's size distribution and in particular its activity median aerodynamic diameter (AMAD)is important for determining the fractional deposition of inhaled particles in the respiratory tract and the resulting doses. Respiratory tract models have been published by the International Commission on radiological Protection (ICRP).The former model has recommended a default AMAD of 1 micron for the calculation of dose coefficients for workers in the nuclear industry [1].The recent model recommends a 5 microns default diameter for occupational exposure which is considered to be more representative of workplace aerosols [2]. Several researches on radioactive aerosol's size distribution in nuclear workplaces has supported this recommendation [3,4].This paper presents the results of radioactive aerosols size distribution measurements taken at several workplaces of the uranium production process

  8. Tariffing of energy measured consumers in the distribution network

    International Nuclear Information System (INIS)

    2006-01-01

    Criteria for socio-economic effective tariffing of energy-measured clients in the distribution network are discussed (i.e. households, leisure homes and smaller business clients), this means consumers that do not have hourly measurements or effect measurements. The tariffs should be based on variable segments that reflect short-term marginal costs in the network (in practice loss of transfer) and fixed segments that to the least extent possible influence the consumers' decisions in the choice of energy solutions, both in short term and long term. High-priced energy segments and effect based fixed segments may give unfortunate socio-economic price signals compared to the marginal long-term network costs. A fixed segment per measurement unit is in principle completely neutral, but it is to some extent vulnerable to strategic adjustments if the consumers choose collective measurement. This is not necessarily a big problem in practice (author)

  9. Measurements of the electron dose distribution near inhomogeneities using a plastic scintillation detector

    International Nuclear Information System (INIS)

    Wells, C.M.M.; Mackie, T.R.; Podgorsak, M.B.; Holmes, M.A.; Papanikolaou, N.; Reckwerdt, P.J.; Cygler, J.; Rogers, D.W.O.; Bielajew, A.F.; Schmidt, D.G.

    1994-01-01

    Accurate measurement of the electron dose distribution near an inhomogeneity is difficult with traditional dosimeters which themselves perturb the electron field. The authors tested the performance of a new high resolution, water-equivalent plastic scintillation detector which has ideal properties for this application. A plastic scintillation detector with a 1 mm diameter, 3 mm long cylindrical sensitive volume was used to measure the dose distributions behind standard benchmark inhomogeneities in water phantoms. The plastic scintillator material is more water equivalent than polystyrene in terms of its mass collision stopping power and mass scattering power. Measurements were performed for beams of electrons having initial energies of 6 and 18 MeV at depths from 0.2-4.2 cm behind the inhomogeneities. The detector reveals hot and cold spots behind heterogeneities at resolutions equivalent to typical film digitizer spot sizes. Plots of the dose distributions behind air, aluminum, lead, and formulations for cortical and inner bone-equivalent materials are presented. The plastic scintillation detector is suited for measuring the electron dose distribution near an inhomogeneity. 14 refs., 9 figs

  10. Measurement of Vehicle Air Conditioning Pull-Down Period

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, John F [ORNL; Huff, Shean P [ORNL; Moore, Larry G [ORNL; West, Brian H [ORNL

    2016-08-01

    Air conditioner usage was characterized for high heat-load summer conditions during short driving trips using a 2009 Ford Explorer and a 2009 Toyota Corolla. Vehicles were parked in the sun with windows closed to allow the cabin to become hot. Experiments were conducted by entering the instrumented vehicles in this heated condition and driving on-road with the windows up and the air conditioning set to maximum cooling, maximum fan speed and the air flow setting to recirculate cabin air rather than pull in outside humid air. The main purpose was to determine the length of time the air conditioner system would remain at or very near maximum cooling power under these severe-duty conditions. Because of the variable and somewhat uncontrolled nature of the experiments, they serve only to show that for short vehicle trips, air conditioning can remain near or at full cooling capacity for 10-minutes or significantly longer and the cabin may be uncomfortably warm during much of this time.

  11. The influence of the atmospheric refractive index on radio Xmax measurements of air showers

    Directory of Open Access Journals (Sweden)

    Corstanje Arthur

    2017-01-01

    Full Text Available The refractive index of the atmosphere, which is n ≈ 1:0003 at sea level, varies with altitude and with local temperature, pressure and humidity. When performing radio measurements of air showers, natural variations in n will change the radio lateral intensity distribution, by changing the Cherenkov angle. Using CoREAS simulations, we have evaluated the systematic error on measurements of the shower maximum Xmax due to variations in n. It was found that a 10% increase in refractivity (n – 1 leads to an underestimation of Xmax between 8 and 22 g/cm2 for proton-induced showers at zenith angles from 15 to 45 degrees, respectively.

  12. Ecoflex: Improving air quality with green dynamic traffic management based on real time air quality measurements

    NARCIS (Netherlands)

    Baalen, J. van; Koning, A. de; Voogt, M.; Stelwagen, U.; Turksma, S.

    2011-01-01

    Across the world, air quality regulations are breached due to localized high pollution episodes in specific locations, or "hotspots". Advances in air pollution monitoring techniques enable hotspots to be identified more effectively; however challenges remain as to how best to reduce the incidence

  13. Distribution of kerma rate in the air inside of hemodynamic room for typical projections of interventionist cardiology procedures

    International Nuclear Information System (INIS)

    Sanchez, Mirtha Elizabet Gamarra

    2008-01-01

    The evaluation of dose to physicians involved in Interventional Cardiology (IC) is an extreme important matter due to the high and non-uniform distribution of dose values. The radiation control during each procedure is complex and the reasons for the high exposures have many different causes. Many international recommendations have already been written aiming the radiation protection optimization in IC. In Brazil, there is not any special orientation for the protection of those occupational persons, nor a specific legislation. The purpose of this work is to evaluate the air kerma rate at critical anatomic regions of the occupationally exposed staff that carry out IC procedures, in representative incidences in order to give subsidies for individual monitoring procedures implementation and to give more information about their radiation protection. The air kerma rate has been measured in the often used condition in the two more common IC procedures namely angiography and coronary angioplasty, using an adult patient simulator irradiated under RAO, LAO and AP projections for fluoro and digital acquisition modes. The measurements have been made in 45 points around the examination table at 5 different representatives heights of: eyes lens, thorax, hands, gonads and knees. AP projection shows the smaller scattered radiation contributions and a more homogeneous exposure distribution. The digital acquisition mode gives air kerma rates about 4 times higher than fluoro mode for LAO projection in the position occupied by the interventionist doctor, the anesthetist and the nursing staff. The most critical anatomic regions are: knees and gonads (without protection). On the physician hands position, values as high as 5 mGy/h have been measured, which can overpass, depending on the number of procedures done, the individual occupational annual limit. Therefore, in IC it is necessary to implement additional protection tools, elaborate safety guides (based on international experiences

  14. Experimental study of air-cooled water condensation in slightly inclined circular tube using infrared temperature measurement technique

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyungdae [Nuclear Engineering Department, Kyung Hee University, Yongin (Korea, Republic of); Kwon, Tae-Soon [Korea Atomic Energy Research Institute, Daedeok-daero 989-111, Yuseong-gu, Daejeon 305-353 (Korea, Republic of); Kim, Dong Eok, E-mail: dekim@knu.ac.kr [Department of Precision Mechanical Engineering, Kyungpook National University, Sangju (Korea, Republic of)

    2016-11-15

    Highlights: • Air-cooled condensation experiments in an inclined Pyrex glass tube were performed. • High-resolution wall temperature data and flow regime formations could be obtained. • The local heat flux was strongly dependent on the air-side heat transfer. • A CFD analysis was conducted for calculating the local heat flux distribution. - Abstract: This study presents the results of an investigation of the air-cooled water condensation heat transfer characteristics inside a slightly inclined circular tube made of transparent Pyrex glass. The high-resolution wall temperature data and stratified film formations could be obtained with the assistance of an infrared (IR) thermometry technique and side-view visualization using a CCD camera. In all experimental cases, the condensation flow patterns were in the fully-stratified flow region. In addition, the experimentally measured void fraction corresponded well with the logarithmic mean void fraction model. The local temperature differences in the cooling air flow across the condenser tube and high-resolution temperature profiles on the tube’s outer wall were obtained in the experimental measurements. Under the experimental conditions of this study, the local heat flux distributions in the longitudinal direction of the test tube were strongly dependent on the cooling air velocity. And, with the help of IR thermometry, the tube outer wall temperature data at 45 local points could be measured. From the data, the asymmetry distribution of the local wall temperatures and the accurate location of the transition from two-phase mixture to single phase liquid inside the tube could be obtained. Also, the analysis of the thermal resistances by condensation, wall conduction and air convection showed that the air convective heat transfer behavior can play a dominant role to the local heat transfer characteristics. Finally, in order to obtain the local heat flux distribution along the tube’s outer wall, a two

  15. Measurement of the muon content in air showers at the Pierre Auger Observatory

    Directory of Open Access Journals (Sweden)

    Veberič Darko

    2016-01-01

    Full Text Available The muon content of extensive air showers produced by ultra-high energy cosmic rays is an observable sensitive to the composition of primary particles and to the properties of hadronic interactions governing the evolution of air-shower cascades. We present different methods for estimation of the number of muons at the ground and the muon production depth. These methods use measurements of the longitudinal, lateral, and temporal distribution of particles in air showers recorded by the detectors of the Pierre Auger Observatory. The results, obtained at about 140 TeV center-of-mass energy for proton primaries, are compared to the predictions of LHC-tuned hadronic-interaction models used in simulations with different primary masses. The models exhibit a deficitin the predicted muon content. The combination of these results with other independent mass composition analyses, such as those involving the depth of shower maximum observablemax, provide additional constraints on hadronic-interaction models for energies beyond the reach of the LHC.

  16. Alpha radioactivity measurement technology with ionized air type measurement. Applicability evaluation to verification of the clearance level

    International Nuclear Information System (INIS)

    Mita, Yutaka; Matsumura, Toshihiro; Yokoyama, Kaoru; Sugitsue, Noritake

    2008-10-01

    The purpose of this test is to evaluate the applicability of the clearance level measuring system by Ionized Air Type Measurement after decontaminated by sulfuric acid sample. In Ningyo-toge Environmental Engineering Center. The equipment and radioactive waste which were contaminated with uranium are generated so much in future dismantling stage. In our plan, some of equipments and radioactive waste are contaminated to a clearance level, and cut down on decommission and disposal expense. This plan needs the alpha-rays measurement technology of the very low level. We think that ionized Air transfer measurement technology is promising as of clearance verification technology. The ionized Air transfer measurement technology applied to the Ionized Air Type Measurement can measure plan radioactivity of a very low level. Moreover, as compared with a direct survey, there is the merit which can be measured in a short time. However ionized Air transfer measurement technology is new technology. Therefore, there is almost no measurement track record. Furthermore, the date about the influence of a background, a detection limit, measurement performance, and reliability is insufficient. So, this measurement test estimated applicability as clearance level verification of an Ionized Air Type Measurement. (author)

  17. Application of tethered balloon for studying vertical distribution of air pollutants within lower tropsphere of Shanghai

    Science.gov (United States)

    Zhang, K.; Wang, D.; Fu, Q.; Xiu, G.; Duan, Y.

    2016-12-01

    Tethered balloon-based measurement campaign of particle number concentration (PNC) and particle number size distribution (PNSD) in the range of 15.7-661.2 nm was conducted within the lower troposphere of 1000 m in Shanghai, a Chinses megacity, in December 2015. The meteorological condition, PNC, and PNSD were synchronous measured at ground-based station as well as on the tethered balloon. Overall, the mixing layer height (MLH) showed a peak at about LST 14:00-15:00. On ground level, the 88.2 nm particles had the highest number concentration. The Pearson correlation analysis based on the ground level data shows the Pearson correlation coefficient between PNC and NO2was 0.774. The synchronous measurement of PNC and PNSD on ground level and on the tethered balloon showed the 15.7-200 nm particles had higher PNC on ground level, but the PNC of 200-661.2 nm particles are higher at 400 m. And the wind condition showed a strong influence on PNC.The vertical profiles of meteorological parameters and air pollutants was observed. The particle mass concentration, ozone concentration, temperature, and humidity all showed a quick change when the balloon across the atmosphere boundary layer. One episodic haze event (Dec 22nd-Dec 23rd) was selected with specific focus on the variation of PNSD and PNC vertical profiles. Before the haze, the PNC at ground was 9281 cm-3. The MaxDm (the particle diameter with the highest number concentration) was 53.3 nm at that time. Due to the shallow MLH, the MaxDm changed rapidly to 126.3 nm at 321 m. During the haze, the MaxDm and the PNC on ground level was 126.3 nm and 18515 cm-3 respectively. And a quick drop of PNC was observed at 553 m. This may due to the change of wind direction, temperature, and relative humidity. At the end of haze, the MaxDm and the PNC on ground level was 126.3 nm and 10711 cm-3 respectively. The highest MaxDm during those three launches all appeared at a high altitude, usually above 300 m. This result is consisted

  18. Real-Time Aerodynamic Parameter Estimation without Air Flow Angle Measurements

    Science.gov (United States)

    Morelli, Eugene A.

    2010-01-01

    A technique for estimating aerodynamic parameters in real time from flight data without air flow angle measurements is described and demonstrated. The method is applied to simulated F-16 data, and to flight data from a subscale jet transport aircraft. Modeling results obtained with the new approach using flight data without air flow angle measurements were compared to modeling results computed conventionally using flight data that included air flow angle measurements. Comparisons demonstrated that the new technique can provide accurate aerodynamic modeling results without air flow angle measurements, which are often difficult and expensive to obtain. Implications for efficient flight testing and flight safety are discussed.

  19. Air quality impacts of projections of natural gas-fired distributed generation

    Science.gov (United States)

    Horne, Jeremy R.; Carreras-Sospedra, Marc; Dabdub, Donald; Lemar, Paul; Nopmongcol, Uarporn; Shah, Tejas; Yarwood, Greg; Young, David; Shaw, Stephanie L.; Knipping, Eladio M.

    2017-11-01

    This study assesses the potential impacts on emissions and air quality from the increased adoption of natural gas-fired distributed generation of electricity (DG), including displacement of power from central power generation, in the contiguous United States. The study includes four major tasks: (1) modeling of distributed generation market penetration; (2) modeling of central power generation systems; (3) modeling of spatially and temporally resolved emissions; and (4) photochemical grid modeling to evaluate the potential air quality impacts of increased DG penetration, which includes both power-only DG and combined heat and power (CHP) units, for 2030. Low and high DG penetration scenarios estimate the largest penetration of future DG units in three regions - New England, New York, and California. Projections of DG penetration in the contiguous United States estimate 6.3 GW and 24 GW of market adoption in 2030 for the low DG penetration and high DG penetration scenarios, respectively. High DG penetration (all of which is natural gas-fired) serves to offset 8 GW of new natural gas combined cycle (NGCC) units, and 19 GW of solar photovoltaic (PV) installations by 2030. In all scenarios, air quality in the central United States and the northwest remains unaffected as there is little to no DG penetration in those states. California and several states in the northeast are the most impacted by emissions from DG units. Peak increases in maximum daily 8-h average ozone concentrations exceed 5 ppb, which may impede attainment of ambient air quality standards. Overall, air quality impacts from DG vary greatly based on meteorological conditions, proximity to emissions sources, the number and type of DG installations, and the emissions factors used for DG units.

  20. Remote measurement of microwave distribution based on optical detection

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Zhong; Ding, Wenzheng; Yang, Sihua; Chen, Qun, E-mail: redrocks-chenqun@hotmail.com, E-mail: xingda@scnu.edu.cn; Xing, Da, E-mail: redrocks-chenqun@hotmail.com, E-mail: xingda@scnu.edu.cn [MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science, South China Normal University, Guangzhou 510631 (China)

    2016-01-04

    In this letter, we present the development of a remote microwave measurement system. This method employs an arc discharge lamp that serves as an energy converter from microwave to visible light, which can propagate without transmission medium. Observed with a charge coupled device, quantitative microwave power distribution can be achieved when the operators and electronic instruments are in a distance from the high power region in order to reduce the potential risk. We perform the experiments using pulsed microwaves, and the results show that the system response is dependent on the microwave intensity over a certain range. Most importantly, the microwave distribution can be monitored in real time by optical observation of the response of a one-dimensional lamp array. The characteristics of low cost, a wide detection bandwidth, remote measurement, and room temperature operation make the system a preferred detector for microwave applications.

  1. Measurement of the distribution coefficient between soil and Cesium-137

    International Nuclear Information System (INIS)

    Tejada V, S.; Hernandez P, M.

    1996-01-01

    The measurement of the distribution coefficient of Cs-137 is currently performed by batch method between radioisotope solution and which was collected from the Mexican Disposal Site, near the town of Maquixco, in the state of Mexico. The Kd values were obtained in activity concentration of Cs-137 of 100 Bq. The solution is shaken for seven days at 25 o C when the maximum amount of radionuclide is absorbed by the soil. The radionuclide in solution is measured by gamma spectrometry. The results obtained from batch method show that the distribution coefficients were from 144 to 660 ml/g for fine soil particles. This work is currently done as part of the site characterization studies for the disposal of low level rad-waste. (authors). 10 refs., 2 tabs

  2. Measures of dependence for multivariate Lévy distributions

    Science.gov (United States)

    Boland, J.; Hurd, T. R.; Pivato, M.; Seco, L.

    2001-02-01

    Recent statistical analysis of a number of financial databases is summarized. Increasing agreement is found that logarithmic equity returns show a certain type of asymptotic behavior of the largest events, namely that the probability density functions have power law tails with an exponent α≈3.0. This behavior does not vary much over different stock exchanges or over time, despite large variations in trading environments. The present paper proposes a class of multivariate distributions which generalizes the observed qualities of univariate time series. A new consequence of the proposed class is the "spectral measure" which completely characterizes the multivariate dependences of the extreme tails of the distribution. This measure on the unit sphere in M-dimensions, in principle completely general, can be determined empirically by looking at extreme events. If it can be observed and determined, it will prove to be of importance for scenario generation in portfolio risk management.

  3. Measurement of the Muon Content of Air Showers with IceTop

    Science.gov (United States)

    Gonzalez, JG; IceCube Collaboration

    2016-05-01

    IceTop, the surface component of the IceCube detector, has measured the energy spectrum of cosmic ray primaries in the range between 1.6 PeV and 1.3 EeV. IceTop can also be used to measure the average density of GeV muons in the shower front at large radial distances (> 300 m) from the shower axis. Wei present the measurement of the muon lateral distribution function for primary cosmic rays with energies between 1.6 PeV and about 0.1 EeV, and compare it to proton and iron simulations. We also discuss how this information can be exploited in the reconstruction of single air shower events. By combining the information on the muon component with that of the electromagnetic component of the air shower, we expect to reduce systematic uncertainties in the inferred mass composition of cosmic rays arising from theoretical uncertainties in hadronic interaction models.

  4. What determines the periportal free air, and ligamentum teres and falciform ligament signs on CT: Can these specific air distributions be valuable predictors of gastroduodenal perforation?

    International Nuclear Information System (INIS)

    Choi, A Lam; Jang, Kyung Mi; Kim, Min-Jeong; Koh, Sung Hye; Lee, Yul; Min, Kwangseon; Choi, Dongil

    2011-01-01

    Purpose: The purpose of this retrospective study was to determine what gives rise to the periportal free air, and ligamentum teres and falciform ligament signs on CT in patients with gastrointestinal (GI) tract perforation, and whether these specific air distributions can play a clinically meaningful role in the diagnosis of gastroduodenal perforation. Material and methods: Ninety-three patients who underwent a diagnostic CT scan before laparotomy for a GI tract perforation were included. The readers assessed the presence of specific air distributions on CT (periportal free air, and ligamentum teres and falciform ligament signs). The readers also assessed the presence of strong predictors of gastroduodenal perforation (focal defects in the stomach and duodenal bulb wall, concentrated extraluminal air bubbles in close proximity to the stomach and duodenal bulb, and wall thickening at the stomach and duodenal bulb). The specific air distributions were assessed according to perforation sites, and the elapsed time and amount of free air, and then compared with the strong predictors of gastroduodenal perforation by using statistical analysis. Results: All specific air distributions were more frequently present in patients with gastroduodenal perforation than lower GI tract perforation, but only the falciform ligament sign was statistically significant (p < 0.05). The presence of all three specific air distributions was demonstrated in only 13 (20.6%) of 63 patients with gastroduodenal perforation. Regardless of the perforation sites, the falciform ligament sign was present significantly more frequently with an increase in the amount of free air on multiple logistic regression analysis (adjusted odds ratio, 1.29; p < 0.001). The sensitivity, specificity, accuracy, and positive predictive and negative predictive values of each strong predictor for the diagnosis of gastroduodenal perforation were higher than those of specific air distributions. The focal wall thickening

  5. Air pollution exposure during critical time periods in gestation and alterations in cord blood lymphocyte distribution: a cohort of livebirths

    Directory of Open Access Journals (Sweden)

    Herr Caroline EW

    2010-08-01

    Full Text Available Abstract Background Toxic exposures have been shown to influence maturation of the immune system during gestation. This study investigates the association between cord blood lymphocyte proportions and maternal exposure to air pollution during each gestational month. Methods Cord blood was analyzed using a FACSort flow cytometer to determine proportions of T lymphocytes (CD3+ cells and their subsets, CD4+ and CD8+, B lymphocytes (CD19+ and natural killer (NK cells. Ambient air concentrations of 12 polycyclic aromatic hydrocarbons (PAH and particulate matter 2.5 were measured using fixed site monitors. Arithmetic means of these pollutants, calculated for each gestational month, were used as exposure metrics. Data on covariates were obtained from medical records and questionnaires. Multivariable linear regression models were fitted to estimate associations between monthly PAH or PM2.5 and cord blood lymphocytes, adjusting for year of birth and district of residence and, in further models, gestational season and number of prior live births. Results The adjusted models show significant associations between PAHs or PM2.5 during early gestation and increases in CD3+ and CD4+ lymphocytes percentages and decreases in CD19+ and NK cell percentages in cord blood. In contrast, exposures during late gestation were associated with decreases in CD3+ and CD4+ fractions and increases in CD19+ and NK cell fractions. There was no significant association between alterations in lymphocyte distribution and air pollution exposure during the mid gestation. Conclusions PAHs and PM2.5 in ambient air may influence fetal immune development via shifts in cord blood lymphocytes distributions. Associations appear to differ by exposure in early versus late gestation.

  6. Measurement of fuel importance distribution in non-uniformly distributed fuel systems

    International Nuclear Information System (INIS)

    Yamane, Yoshihiro; Hirano, Yasushi; Yasui, Hazime; Izima, Kazunori; Shiroya, Seiji; Kobayashi, Keiji.

    1995-01-01

    A reactivity effect due to a spatial variation of nuclear fuel concentration is an important problem for nuclear criticality safety in a reprocessing plant. As a theory estimating this reactivity effect, the Goertzel and fuel importance theories are well known. It has been shown that the Goertzel's theory is valid in the range of our experiments based on measurements of reactivity effect and thermal neutron flux in non-uniformly distributed fuel systems. On the other hand, there have been no reports concerning systematic experimental studies on the flatness of fuel importance which is a more general index than the Goertzel's theory. It is derived from the perturbation theory that the fuel importance is proportional to the reactivity change resulting from a change of small amount of fuel mass. Using a uniform and three kinds of nonuniform fuel systems consisting of 93.2% enriched uranium plates and polyethylene plates, the fuel importance distributions were measured. As a result, it was found experimentally that the fuel importance distribution became flat, as its reactivity effect became large. Therefore it was concluded that the flatness of fuel importance distribution is the useful index for estimating reactivity effect of non-uniformly distributed fuel system. (author)

  7. Estimation of uncertainty in tracer gas measurement of air change rates.

    Science.gov (United States)

    Iizuka, Atsushi; Okuizumi, Yumiko; Yanagisawa, Yukio

    2010-12-01

    Simple and economical measurement of air change rates can be achieved with a passive-type tracer gas doser and sampler. However, this is made more complex by the fact many buildings are not a single fully mixed zone. This means many measurements are required to obtain information on ventilation conditions. In this study, we evaluated the uncertainty of tracer gas measurement of air change rate in n completely mixed zones. A single measurement with one tracer gas could be used to simply estimate the air change rate when n = 2. Accurate air change rates could not be obtained for n ≥ 2 due to a lack of information. However, the proposed method can be used to estimate an air change rate with an accuracy of air change rate can be avoided. The proposed estimation method will be useful in practical ventilation measurements.

  8. Atmospheric properties measurements and data collection from a hot-air balloon

    Science.gov (United States)

    Watson, Steven M.; Olson, N.; Dalley, R. P.; Bone, W. J.; Kroutil, Robert T.; Herr, Kenneth C.; Hall, Jeff L.; Schere, G. J.; Polak, M. L.; Wilkerson, Thomas D.; Bodrero, Dennis M.; Borys, R. O.; Lowenthal, D.

    1995-02-01

    Tethered and free-flying manned hot air balloons have been demonstrated as platforms for various atmospheric measurements and remote sensing tasks. We have been performing experiments in these areas since the winter of 1993. These platforms are extremely inexpensive to operate, do not cause disturbances such as prop wash and high airspeeds, and have substantial payload lifting and altitude capabilities. The equipment operated and tested on the balloons included FTIR spectrometers, multi-spectral imaging spectrometer, PM10 Beta attenuation monitor, mid- and far-infrared cameras, a radiometer, video recording equipment, ozone meter, condensation nuclei counter, aerodynamic particle sizer with associated computer equipment, a tethersonde and a 2.9 kW portable generator providing power to the equipment. Carbon monoxide and ozone concentration data and particle concentrations and size distributions were collected as functions of altitude in a wintertime inversion layer at Logan, Utah and summertime conditions in Salt Lake City, Utah and surrounding areas. Various FTIR spectrometers have been flown to characterize chemical plumes emitted from a simulated industrial stack. We also flew the balloon into diesel and fog oil smokes generated by U.S. Army and U.S. Air Force turbine generators to obtain particle size distributions.

  9. Measured PET Data Characterization with the Negative Binomial Distribution Model.

    Science.gov (United States)

    Santarelli, Maria Filomena; Positano, Vincenzo; Landini, Luigi

    2017-01-01

    Accurate statistical model of PET measurements is a prerequisite for a correct image reconstruction when using statistical image reconstruction algorithms, or when pre-filtering operations must be performed. Although radioactive decay follows a Poisson distribution, deviation from Poisson statistics occurs on projection data prior to reconstruction due to physical effects, measurement errors, correction of scatter and random coincidences. Modelling projection data can aid in understanding the statistical nature of the data in order to develop efficient processing methods and to reduce noise. This paper outlines the statistical behaviour of measured emission data evaluating the goodness of fit of the negative binomial (NB) distribution model to PET data for a wide range of emission activity values. An NB distribution model is characterized by the mean of the data and the dispersion parameter α that describes the deviation from Poisson statistics. Monte Carlo simulations were performed to evaluate: (a) the performances of the dispersion parameter α estimator, (b) the goodness of fit of the NB model for a wide range of activity values. We focused on the effect produced by correction for random and scatter events in the projection (sinogram) domain, due to their importance in quantitative analysis of PET data. The analysis developed herein allowed us to assess the accuracy of the NB distribution model to fit corrected sinogram data, and to evaluate the sensitivity of the dispersion parameter α to quantify deviation from Poisson statistics. By the sinogram ROI-based analysis, it was demonstrated that deviation on the measured data from Poisson statistics can be quantitatively characterized by the dispersion parameter α, in any noise conditions and corrections.

  10. Measurement of Dijet Angular Distributions and Search for Quark Compositeness

    International Nuclear Information System (INIS)

    Gomez, B.; Hoeneisen, B.; Mooney, P.; Negret, J.P.; Davis, K.; Fein, D.; Forden, G.E.; Guida, J.A.; James, E.; Johns, K.; Nang, F.; Narayanan, A.; Rutherfoord, J.; Butler, J.M.; Fatyga, M.; Featherly, J.; Gibbard, B.; Gordon, H.; Graf, N.; Kahn, S.; Kotcher, J.; Protopopescu, S.; Rajagopalan, S.; Bantly, J.; Cullen-Vidal, D.; Cutts, D.; Guida, J.M.; Hoftun, J.S.; Partridge, R.; Grinstein, S.; Piegaia, R.; Bloom, P.; Fisyak, Y.; Glenn, S.; Grim, G.; Klopfenstein, C.; Lander, R.; Mani, S.; Fahland, T.; Hall, R.E.; Boswell, C.; Choudhary, B.C.; Cochran, J.; Ellison, J.; Gartung, P.; Gounder, K.; Huehn, T.; Alves, G.A.; Carvalho, W.; Maciel, A.K.; Motta, H.; Nicola, M.; Santoro, A.; Castilla-Valdez, H.; Gonzalez Solis, J.L.; Hernandez-Montoya, R.; Magana-Mendoza, L.; Sanchez-Hernandez, A.; Adam, I.; Kotwal, A.V.; Bhattacharjee, M.; Ahn, S.; Baldin, B.; Bartlett, J.F.; Bhat, P.C.; Boehnlein, A.; Borcherding, F.; Brandt, A.; Bross, A.; Christenson, J.H.; Cooper, W.E.; Demarteau, M.; Denisov, D.; Diehl, H.T.; Diesburg, M.; Feher, S.; Fisk, H.E.; Flattum, E.; Fuess, S.; Genser, K.; Gerber, C.E.; Green, D.R.; Greenlee, H.; Grossman, N.; Haggerty, H.; Hansen, S.; Heintz, U.; Hobbs, J.

    1998-01-01

    We have measured the dijet angular distribution in √(s)=1.8 TeV p bar p collisions using the D0 detector. Order α 3 s QCD predictions are in good agreement with the data. At 95% confidence limit the data exclude models of quark compositeness in which the contact interaction scale is below 2TeV. copyright 1998 The American Physical Society

  11. Technical assessment of air quality measuring analyzers; Evaluation technique des analyseurs de mesure de la qualite de l`air

    Energy Technology Data Exchange (ETDEWEB)

    Tatry, V. [Laboratoire de mesures a l`air ambiant, Dept. Mesures et Analyses, INERIS, (France)

    1996-12-31

    Air quality measuring analyzers are assessed in order to verify their measuring performance and to examine their aptitude to field measurements. For ensuring such assessment, the INERIS institute (France) disposes of three climatic enclosures, gas mixture emission systems and data acquisition systems. The assessment methodology is presented together with the various possible results: response time, linearity and limits determination, calibration studies, thresholds, drifts, hysteresis, physical detrimental effects, etc. Applications such as analyzers for one or more pollutants in ambient air and at the emission source (portable multi-gas analyzers) are presented, together with their results

  12. Measuring the Air Quality and Transportation Impacts of Infill Development

    Science.gov (United States)

    This report summarizes three case studies. The analysis shows how standard forecasting tools can be modified to capture at least some of the transportation and air quality benefits of brownfield and infill development.

  13. Air Quality Measures on the National Environmental Health Tracking Network

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Environmental Protection Agency (EPA) provides air pollution data about ozone and particulate matter (PM2.5) to CDC for the Tracking Network. The EPA maintains a...

  14. Plans and Measures for Avoiding Casting-Air-Pollution

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jian

    2003-01-01

    This article presents plans of preventing casting-air-pollution in practice, and some avoiding methods in detail. In modern times, environment protection is looked high upon day by day; green-casting thus becomes more and more important.

  15. Comparison of Measured Dark Current Distributions with Calculated Damage Energy Distributions in HgCdTe

    Science.gov (United States)

    Marshall, C. J.; Marshall, P. W.; Howe, C. L.; Reed, R. A.; Weller, R. A.; Mendenhall, M.; Waczynski, A.; Ladbury, R.; Jordan, T. M.

    2007-01-01

    This paper presents a combined Monte Carlo and analytic approach to the calculation of the pixel-to-pixel distribution of proton-induced damage in a HgCdTe sensor array and compares the results to measured dark current distributions after damage by 63 MeV protons. The moments of the Coulombic, nuclear elastic and nuclear inelastic damage distributions were extracted from Monte Carlo simulations and combined to form a damage distribution using the analytic techniques first described in [1]. The calculations show that the high energy recoils from the nuclear inelastic reactions (calculated using the Monte Carlo code MCNPX [2]) produce a pronounced skewing of the damage energy distribution. While the nuclear elastic component (also calculated using the MCNPX) contributes only a small fraction of the total nonionizing damage energy, its inclusion in the shape of the damage across the array is significant. The Coulombic contribution was calculated using MRED [3-5], a Geant4 [4,6] application. The comparison with the dark current distribution strongly suggests that mechanisms which are not linearly correlated with nonionizing damage produced according to collision kinematics are responsible for the observed dark current increases. This has important implications for the process of predicting the on-orbit dark current response of the HgCdTe sensor array.

  16. On the measurement of the (multidimensional) inequality of health distributions

    DEFF Research Database (Denmark)

    Hougaard, Jens Leth; Moreno-Ternero, Juan D.; Østerdal, Lars Peter Raahave

    2013-01-01

    a standard mathematical structure. We single out two families of (absolute and relative) multidimensional health inequality indices, inspired by the classical normative approach to income inequality measurement. We also discuss how to extend the analysis to deal with the related problem of health deprivation......Health outcomes are often described according to two dimensions: quality of life and quantity of life. We analyze the measurement of inequality of health distributions referring to these two dimensions. Our analysis relies on a novel treatment of the quality-of-life dimension, which might not have...

  17. Predicted and measured velocity distribution in a model heat exchanger

    International Nuclear Information System (INIS)

    Rhodes, D.B.; Carlucci, L.N.

    1984-01-01

    This paper presents a comparison between numerical predictions, using the porous media concept, and measurements of the two-dimensional isothermal shell-side velocity distributions in a model heat exchanger. Computations and measurements were done with and without tubes present in the model. The effect of tube-to-baffle leakage was also investigated. The comparison was made to validate certain porous media concepts used in a computer code being developed to predict the detailed shell-side flow in a wide range of shell-and-tube heat exchanger geometries

  18. Air Traffic Complexity Measurement Environment (ACME): Software User's Guide

    Science.gov (United States)

    1996-01-01

    A user's guide for the Air Traffic Complexity Measurement Environment (ACME) software is presented. The ACME consists of two major components, a complexity analysis tool and user interface. The Complexity Analysis Tool (CAT) analyzes complexity off-line, producing data files which may be examined interactively via the Complexity Data Analysis Tool (CDAT). The Complexity Analysis Tool is composed of three independently executing processes that communicate via PVM (Parallel Virtual Machine) and Unix sockets. The Runtime Data Management and Control process (RUNDMC) extracts flight plan and track information from a SAR input file, and sends the information to GARP (Generate Aircraft Routes Process) and CAT (Complexity Analysis Task). GARP in turn generates aircraft trajectories, which are utilized by CAT to calculate sector complexity. CAT writes flight plan, track and complexity data to an output file, which can be examined interactively. The Complexity Data Analysis Tool (CDAT) provides an interactive graphic environment for examining the complexity data produced by the Complexity Analysis Tool (CAT). CDAT can also play back track data extracted from System Analysis Recording (SAR) tapes. The CDAT user interface consists of a primary window, a controls window, and miscellaneous pop-ups. Aircraft track and position data is displayed in the main viewing area of the primary window. The controls window contains miscellaneous control and display items. Complexity data is displayed in pop-up windows. CDAT plays back sector complexity and aircraft track and position data as a function of time. Controls are provided to start and stop playback, adjust the playback rate, and reposition the display to a specified time.

  19. An Industrial Gauge for Measuring The Phase Distribution of Galvanneal

    Energy Technology Data Exchange (ETDEWEB)

    Christopher BUrnett; Roland Gouel; James R. Phillips

    1996-01-19

    Augmentation of the internal software of a commercial x-ray fluorescence gauge is shown to enable the instrument to extend its continuous on-line real-time measurements of a galvanneal coating's total elemental content to encompass similar measurements of the relative thickness of the coating's three principal metallurgical phases. The mathematical structure of this software augmentation is derived from the theory of neural networks. The empirical basis for the numerics embedded in the software's decision logic is presented. The performance of the augmented gauge is validated by comparing the gauge-implied real-time phase distribution with the phase distribution independently measured off-line on time-tagged samples drawn from the galvanneal production line where the measurement gauge had been installed. The performance validation is shown to demonstrate good agreement between the gauge and laboratory measurements and to suggest preferred approaches to be followed in future applications of the augmented gauge.

  20. The distribution of mitochondria-rich cells in the gills of air-breathing fishes.

    Science.gov (United States)

    Lin, Hui-Chen; Sung, Wen-Ting

    2003-01-01

    Respiration and ion regulation are the two principal functions of teleostean gills. Mainly found in the gill filaments of fish, mitochondria-rich cells (MRCs) proliferate to increase the ionoregulatory capacity of the gill in response to osmotic challenges. Gill lamellae consist mostly of pavement cells, which are the major site of gas exchange. Although lamellar MRCs have been reported in some fish species, there has been little discussion of which fish species are likely to have lamellar MRCs. In this study, we first compared the number of filament and lamellar MRCs in air-breathing and non-air-breathing fish species acclimated to freshwater and 5 g NaCl L(-1) conditions. An increase in filament MRCs was found in both air-breathing and non-air-breathing fish acclimated to freshwater. Lamellar MRCs were found only in air-breathing species, but the number of lamellar MRCs did not change significantly with water conditions, except in Periophthalmus cantonensis. Next, we surveyed the distribution of MRCs in the gills of 66 fish species (including 29 species from the previous literature) from 12 orders, 28 families, and 56 genera. Our hypothesis that lamellar MRCs are more likely to be found in air-breathing fishes was supported by a significant association between the presence of lamellar MRCs and the mode of breathing at three levels of systematic categories (species, genus, and family). Based on this integrative view of the multiple functions of fish gills, we should reexamine the role of MRCs in freshwater fish.

  1. The Distribution of Flight Tracks Across Air Combat Command Military Training Routes

    National Research Council Canada - National Science Library

    Bradley, Kevin

    1996-01-01

    To validate the flight track dispersion algorithms currently in the ROUTEMAP and MR_NMAP noise models, measurements of the lateral distribution of flight operations were conducted on five low-altitude Military Training (MTRs...

  2. Features of adsorbed chemical elements and their isotopes distribution in iodine air filters AU-1500 of nuclear power plant

    International Nuclear Information System (INIS)

    Neklyudov, I.M.; Dovbnya, A.N.; Dikiy, N.P.; Ledenyov, O.P.; Lyashko, Yu.V.

    2013-01-01

    The main aim of research is to investigate the physical features of spatial distribution of the adsorbed chemical elements and their isotopes in the granular filtering medium in the iodine air filters of the type of AU-1500 in the forced-exhaust ventilation at the nuclear power plant. The ?-activation analysis method is applied to accurately characterize the distribution of the adsorbed radioactive chemical elements and their isotopes in the granular filtering medium in the AU-1500 iodine air filter after its long term operation at the nuclear power plant. The typical spectrum of the detected chemical elements and their isotopes in the AU-1500 iodine air filter, which was exposed by the irradiation of bremsstrahlung gamma-quantum producing by the accelerating electrons in the tantalum target, are obtained. The spatial distributions of the detected chemical element 127 I and some other chemical elements and their isotopes in the layer of absorber, which was made of the cylindrical coal granules of the type of SKT-3, in the AU-1500 iodine air filter are also researched. The possible influences by the standing wave of air pressure in the iodine air filter on the spatial distribution of the chemical elements and their isotopes in the iodine air filter are discussed. The comprehensive analysis of obtained research results on the distribution of the adsorbed chemical elements and their isotopes in the absorber of iodine air filter is performed.

  3. Energy distribution and quantum yield for photoemission from air-contaminated gold surfaces under ultraviolet illumination close to the threshold

    Science.gov (United States)

    Hechenblaikner, Gerald; Ziegler, Tobias; Biswas, Indro; Seibel, Christoph; Schulze, Mathias; Brandt, Nico; Schöll, Achim; Bergner, Patrick; Reinert, Friedrich T.

    2012-06-01

    The kinetic energy distributions of photo-electrons emitted from gold surfaces under illumination by UV-light close to the threshold (photon energy in the order of the material work function) are measured and analyzed. Samples are prepared as chemically clean through Ar-ion sputtering and then exposed to atmosphere for variable durations before quantum yield measurements are performed after evacuation. During measurements, the bias voltage applied to the sample is varied and the resulting emission current measured. Taking the derivative of the current-voltage curve yields the energy distribution which is found to closely resemble the distribution of total energies derived by DuBridge for emission from a free electron gas. We investigate the dependence of distribution shape and width on electrode geometry and contaminant substances adsorbed from the atmosphere, in particular, to water and hydro-carbons. Emission efficiency increases initially during air exposure before diminishing to zero on a timescale of several hours, whilst subsequent annealing of the sample restores emissivity. A model fit function, in good quantitative agreement with the measured data, is introduced which accounts for the experiment-specific electrode geometry and an energy dependent transmission coefficient. The impact of large patch potential fields from contact potential drops between sample and sample holder is investigated. The total quantum yield is split into bulk and surface contributions which are tested for their sensitivity to light incidence angle and polarization. Our results are directly applicable to model parameters for the contact-free discharge system onboard the Laser Interferometer Space Antenna (LISA) Pathfinder spacecraft.

  4. Measuring inequalities in the distribution of the Fiji Health Workforce.

    Science.gov (United States)

    Wiseman, Virginia; Lagarde, Mylene; Batura, Neha; Lin, Sophia; Irava, Wayne; Roberts, Graham

    2017-06-30

    Despite the centrality of health personnel to the health of the population, the planning, production and management of human resources for health remains underdeveloped in many low- and middle-income countries (LMICs). In addition to the general shortage of health workers, there are significant inequalities in the distribution of health workers within LMICs. This is especially true for countries like Fiji, which face major challenges in distributing its health workforce across many inhabited islands. In this study, we describe and measure health worker distributional inequalities in Fiji, using data from the 2007 Population Census, and Ministry of Health records of crude death rates and health workforce personnel. We adopt methods from the economics literature including the Lorenz Curve/Gini Coefficient and Theil Index to measure the extent and drivers of inequality in the distribution of health workers at the sub-national level in Fiji for three categories of health workers: doctors, nurses, and all health workers (doctors, nurses, dentists and health support staff). Population size and crude death rates are used as proxies for health care needs. There are greater inequalities in the densities of health workers at the provincial level, compared to the divisional level in Fiji - six of the 15 provinces fall short of the recommended threshold of 2.3 health workers per 1,000 people. The estimated decile ratios, Gini co-efficient and Thiel index point to inequalities at the provincial level in Fiji, mainly with respect to the distribution of doctors; however these inequalities are relatively small. While populations with lower mortality tend to have a slightly greater share of health workers, the overall distribution of health workers on the basis of need is more equitable in Fiji than for many other LMICs. The overall shortage of health workers could be addressed by creating new cadres of health workers; employing increasing numbers of foreign doctors, including

  5. Correlation and uncertainties evaluation in backscattering of entrance surface air kerma measurements

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, G.J.; Sousa, C.H.S.; Peixoto, J.G.P., E-mail: gt@ird.gov.br [Instituto de Radioproteção e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil)

    2017-07-01

    The air kerma measurement is important to verify the applied doses in radiodiagnostic. The literature determines some methods to measure the entrance surface air kerma or entrance surface dose but some of this methods may increase the measurement with the backscattering. Were done setups of measurements to do correlations between them. The expanded uncertainty exceeded 5% for measurements with backscattering, reaching 8.36%, while in situations where the backscattering was avoided, the uncertainty was 3.43%. (author)

  6. TXRF 'measurements' of concentration distribution below the detection limit

    International Nuclear Information System (INIS)

    Kubala-Kukus, A.; Banas, D.; Braziewicz, J.; Majewska, U.; Mrowczynski, S.; Pajek, M.

    2000-01-01

    We demonstrate that a shape of the concentration distribution of the element in a set of samples, as measured by the TXRF method, can be determined even for the concentrations below the detection limit (DL). This can be done, when the measurements reporting the concentration below DL level are included properly in the analysis of the results. The method developed for such correction is presented and discussed. It is demonstrated that this correction is particularly important when the studied concentrations are close to the DL level of the method, which is a common case for TXRF. In the paper a precision of the developed correction is discussed in details, by using the results of numerical simulations of experiments for different concentration distributions and number of performed measurements. It is demonstrated that the factor, which limits the accuracy of the correction, is the number of measurements, not the correction procedure itself. The applicability and importance of the developed correction is demonstrated for routine TXRF analysis of different types of samples of bio-medical interest. (author)

  7. Effect of weak measurement on entanglement distribution over noisy channels.

    Science.gov (United States)

    Wang, Xin-Wen; Yu, Sixia; Zhang, Deng-Yu; Oh, C H

    2016-03-03

    Being able to implement effective entanglement distribution in noisy environments is a key step towards practical quantum communication, and long-term efforts have been made on the development of it. Recently, it has been found that the null-result weak measurement (NRWM) can be used to enhance probabilistically the entanglement of a single copy of amplitude-damped entangled state. This paper investigates remote distributions of bipartite and multipartite entangled states in the amplitudedamping environment by combining NRWMs and entanglement distillation protocols (EDPs). We show that the NRWM has no positive effect on the distribution of bipartite maximally entangled states and multipartite Greenberger-Horne-Zeilinger states, although it is able to increase the amount of entanglement of each source state (noisy entangled state) of EDPs with a certain probability. However, we find that the NRWM would contribute to remote distributions of multipartite W states. We demonstrate that the NRWM can not only reduce the fidelity thresholds for distillability of decohered W states, but also raise the distillation efficiencies of W states. Our results suggest a new idea for quantifying the ability of a local filtering operation in protecting entanglement from decoherence.

  8. Measurement and application of bidirectional reflectance distribution function

    Science.gov (United States)

    Liao, Fei; Li, Lin; Lu, Chengwen

    2016-10-01

    When a beam of light with certain intensity and distribution reaches the surface of a material, the distribution of the diffused light is related to the incident angle, the receiving angle, the wavelength of the light and the types of the material. Bidirectional Reflectance Distribution Function (BRDF) is a method to describe this distribution. For an optical system, the optical and mechanical materials' BRDF are unique, and if we want to calculate stray light of the system we should know the correct BRDF data of the whole materials. There are fundamental significances in the area of space remote sensor where BRDF is needed in the precise radiation calibration. It is also important in the military field where BRDF can be used in the object identification and target tracking, etc. In this paper, 11 kinds of aerospace materials' BRDF are measured and more than 310,000 groups of BRDF data are achieved , and also a BRDF database is established in China for the first time. With the BRDF data of the database, we can create the detector model, build the stray light radiation surface model in the stray light analysis software. In this way, the stray radiation on the detector can be calculated correctly.

  9. Air Distribution and Ventilation Effectiveness in a room with Floor/Ceiling Heating and Mixing/Displacement Ventilation

    DEFF Research Database (Denmark)

    Wu, Xiaozhou; Fang, Lei; Olesen, Bjarne W.

    2014-01-01

    vertical air temperature differences and air velocities for different hybrid systems are less than 3 C and 0.2 m/s when supply air temperature is 19 C, air change rate is 4.2 h-1, and heated surface temperature of floor/ceiling heating system is 25 C. Ventilation effectiveness of mixing ventilation system...... combined with floor/ceiling heating systems is approximately equal to 1.0, and ventilation effectiveness of displacement ventilation system combined with floor/ceiling heating systems ranges from 1.0 to 1.2. The floor/ceiling heating systems combined with mixing ventilation system have more uniform indoor...... air distribution but smaller ventilation effectiveness compared with the floor/ceiling heating systems combined with displacement ventilation system. With regard to the building heat loss increased by non-uniform indoor air distribution and small ventilation effectiveness, there should be an optimal...

  10. Measurement system for depth dose distribution in cancer therapy

    International Nuclear Information System (INIS)

    Nishizawa, Hiroshi; Fujiwara, Hirotsugu; Tsutaka, Yoshikazu; Ikeda, Ikuo

    1999-01-01

    An accurate estimation of an absorbed dose distribution in human tissue is indispensable to efficiently perform radiotherapy in humans. Previously, various methods for such estimation have been developed, however, there is some problem in those methods, it takes too long times (3-4 hours) to determine the absorbed dose distribution through scanning by ionization chamber in water phantom. So, a determination system of depth dose was developed with an aim to determine the absorbed dose of X-ray or electron beam in materials similar to human body. This system was composed of a detector including scintillation fibers which allows emission due to radio-interaction, CCD camera for determination of light distribution of the emission and personal computer for data processing. Though the accuracy of this system was ±2% similar to that of the conventional measuring method, measuring time was reduced to almost 5 min, markedly shorter than that of the conventional water phantom (3-4 hours). The efficacy of works including the adjustment of irradiation system, planning, etc. would be improved by application of this system. (M.N.)

  11. Measuring air layer volumes retained by submerged floating-ferns Salvinia and biomimetic superhydrophobic surfaces

    Directory of Open Access Journals (Sweden)

    Matthias J. Mayser

    2014-06-01

    Full Text Available Some plants and animals feature superhydrophobic surfaces capable of retaining a layer of air when submerged under water. Long-term air retaining surfaces (Salvinia-effect are of high interest for biomimetic applications like drag reduction in ship coatings of up to 30%. Here we present a novel method for measuring air volumes and air loss under water. We recorded the buoyancy force of the air layer on leaf surfaces of four different Salvinia species and on one biomimetic surface using a highly sensitive custom made strain gauge force transducer setup. The volume of air held by a surface was quantified by comparing the buoyancy force of the specimen with and then without an air layer. Air volumes retained by the Salvinia-surfaces ranged between 0.15 and 1 L/m2 depending on differences in surface architecture. We verified the precision of the method by comparing the measured air volumes with theoretical volume calculations and could find a good agreement between both values. In this context we present techniques to calculate air volumes on surfaces with complex microstructures. The introduced method also allows to measure decrease or increase of air layers with high accuracy in real-time to understand dynamic processes.

  12. Method for measuring the size distribution of airborne rhinovirus

    International Nuclear Information System (INIS)

    Russell, M.L.; Goth-Goldstein, R.; Apte, M.G.; Fisk, W.J.

    2002-01-01

    About 50% of viral-induced respiratory illnesses are caused by the human rhinovirus (HRV). Measurements of the concentrations and sizes of bioaerosols are critical for research on building characteristics, aerosol transport, and mitigation measures. We developed a quantitative reverse transcription-coupled polymerase chain reaction (RT-PCR) assay for HRV and verified that this assay detects HRV in nasal lavage samples. A quantitation standard was used to determine a detection limit of 5 fg of HRV RNA with a linear range over 1000-fold. To measure the size distribution of HRV aerosols, volunteers with a head cold spent two hours in a ventilated research chamber. Airborne particles from the chamber were collected using an Andersen Six-Stage Cascade Impactor. Each stage of the impactor was analyzed by quantitative RT-PCR for HRV. For the first two volunteers with confirmed HRV infection, but with mild symptoms, we were unable to detect HRV on any stage of the impactor

  13. Measurement of proton momentum distributions using a direct geometry instrument

    International Nuclear Information System (INIS)

    Senesi, R; Andreani, C; Kolesnikov, A I

    2014-01-01

    We report the results of inelastic neutron scattering measurements on bulk water and ice using the direct geometry SEQUOIA chopper spectrometer at the Spallation Neutron Source (USA), with incident energy E i = 6 eV. In this set up the measurements allow to access the Deep Inelastic Neutron Scattering regime. The scattering is centred at the proton recoil energy given by the impulse approximation, and the shape of the recoil peak conveys information on the proton momentum distribution in the system. The comparison with the performance of inverse geometry instruments, such as VESUVIO at the ISIS source (UK), shows that complementary information can be accessed by the use of direct and inverse geometry instruments. Analysis of the neutron Compton profiles shows that the proton kinetic energy in ice at 271 K is larger than in room temperature liquid water, in agreement with previous measurements on VESUVIO

  14. Method for measuring the size distribution of airborne rhinovirus

    Energy Technology Data Exchange (ETDEWEB)

    Russell, M.L.; Goth-Goldstein, R.; Apte, M.G.; Fisk, W.J.

    2002-01-01

    About 50% of viral-induced respiratory illnesses are caused by the human rhinovirus (HRV). Measurements of the concentrations and sizes of bioaerosols are critical for research on building characteristics, aerosol transport, and mitigation measures. We developed a quantitative reverse transcription-coupled polymerase chain reaction (RT-PCR) assay for HRV and verified that this assay detects HRV in nasal lavage samples. A quantitation standard was used to determine a detection limit of 5 fg of HRV RNA with a linear range over 1000-fold. To measure the size distribution of HRV aerosols, volunteers with a head cold spent two hours in a ventilated research chamber. Airborne particles from the chamber were collected using an Andersen Six-Stage Cascade Impactor. Each stage of the impactor was analyzed by quantitative RT-PCR for HRV. For the first two volunteers with confirmed HRV infection, but with mild symptoms, we were unable to detect HRV on any stage of the impactor.

  15. Concentration and Size Distribution of Particulate Matter in a Broiler House Ambient Air

    Directory of Open Access Journals (Sweden)

    Ismael Rodrigues Amador

    2016-07-01

    Full Text Available Atmospheric particulate matter (PM is an important constituent of ambient air. The determination of its concentration and size distribution in different environments is essential because of its ability to penetrate deeply into animal and human respiratory tract. In this study, air sampling was performed in a broiler house to estimate the concentration and size distribution of PM emitted along with its activities. Low-vol impactor (< 10 mm, cyclones (< 2.5 e < 1.0 mm, and Sioutas cascade impactor (> 2.5; 1.0 – 2.5; 0.50 – 1.0; 0.25 – 0.50; < 0.25 mm connected with membrane pumps were used. PM10 showed high concentration (209 - 533 mg m-3. PM2.5 and PM1.0 initially showed relatively low concentration (20.8 and 16.0 mg m-3 respectively with significantly increasing levels (412.9 and 344.8 mg m-3 respectively during the samplings. It was also possible to observe the contribution of fine particles. This was evidenced by the high correlation between PM2.5 and PM1.0 and by the profile of particle distribution in the Sioutas sampler. PM concentration levels are considered excessively high, with great potential to affect animal and human health. DOI: http://dx.doi.org/10.17807/orbital.v8i3.847 

  16. Electron-Beam Produced Air Plasma: Optical Measurement of Beam Current

    Science.gov (United States)

    Vidmar, Robert; Stalder, Kenneth; Seeley, Megan

    2006-10-01

    Experiments to quantify the electron beam current and distribution of beam current in air plasma are discussed. The air plasma is produced by a 100-keV 10-mA electron beam source that traverses a transmission window into a chamber with air as a target gas. Air pressure is between 1 mTorr and 760 Torr. Strong optical emissions due to electron impact ionization are observed for the N2 2^nd positive line at 337.1 nm and the N2^+ 1^st negative line at 391.4 nm. Calibration of optical emissions using signals from the isolated transmission window and a Faraday plate are discussed. The calibrated optical system is then used to quantify the electron distribution in the air plasma.

  17. Heat-transfer distributions on biconics at incidence in hypersonic-hypervelocity He, N2, air, and CO2 flows

    Science.gov (United States)

    Miller, C. G.; Micol, J. R.; Gnoffo, P. A.; Wilder, S.E.

    1983-01-01

    Laminar heat-transfer rates were measured on spherically blunted, 13 degrees/F degrees on-axis and bent biconics (fore cone bent 7 degrees upward relative to aft cone) at hypersonic-hypervelocity flow conditions in the Langley Expansion Tube. Freestream velocities from 4.5 to 6.9 km/sec and Mach numbers from 6 to 9 were generated using helium, nitrogen, air, and carbon dioxide test gases, resulting in normal shock density ratios from 4 to 19. Angle of attack, referenced to the axis of the aft cone, was varied from zero to 20 degrees in 4 degree increments. The effect of nose bend, angle of attack, and real-gas phenomena on heating distributions are presented along with comparisons of measurement to prediction from a code which solves the three-dimensional 'parabolized Navier-Stokes' equations.

  18. Using continuous sampling to examine the distribution of traffic related air pollution in proximity to a major road

    Science.gov (United States)

    McAdam, Kim; Steer, Peter; Perrotta, Kim

    2011-04-01

    A study to characterize the distribution of vehicle related air pollution in proximity to a major arterial road was undertaken to inform local land use planning and policy regarding separation distances that could help reduce exposure for new sensitive land use development. Measurements of criteria air contaminants were made at ground level, 10 m, 30 m, and 60 m from curb side, and at 9 m height, 10 m from curb side along a traffic corridor carrying over 34,000 vehicles per day. Pollutant decay with distance or height was not statistically significant for O 3, CO, or SO 2. No clear distance decay pattern emerged for PM 2.5. Compared to concentrations at ground level 30 m from curb side, concentrations at 10 m, 60 m, and 10 m at 9 m height were 83%, 45% and 54% higher, respectively. For NO, NO 2, and NO x, however, there was a statistically significant decline in concentrations with distance with the decay most apparent from 30 m to 60 m from the road. Concentrations at 10 m from curb side at 9 m height were equivalent to (all wind conditions) or less than (downwind conditions) those at 30 m and ground level. These findings suggest that for protection of public health in the near road environment, vertical distance is an important determinant of exposure to pollutants that are key indicators of traffic related air pollution. This has implications for sensitive land use development in proximity to high volume traffic corridors.

  19. 32Si as natural tracer : measurement, global distribution and application

    International Nuclear Information System (INIS)

    Morgenstern, U.

    1997-01-01

    Cosmogenic 32 Si (half-life 140 years) can be applied to the study of environmental circulation processes in the time range of the last 1000 years, a key period for modelling past climate change. Its non-gaseous nature and fairly constant production rate are favourable to quantifying its roe in environmental processes. Applications of 32 Si method were limited due to uncertainties in half-life and poor knowledge of its global distribution, and to its very small natural concentration. Recent developments concerning these problems will be presented with special emphasis to measurement and global distribution, and to application in study of groundwater recharge and flow, glacier dynamics, soil erosion rates and sedimentation in lakes and oceans. (author)

  20. Measurement of probability distributions for internal stresses in dislocated crystals

    Energy Technology Data Exchange (ETDEWEB)

    Wilkinson, Angus J.; Tarleton, Edmund; Vilalta-Clemente, Arantxa; Collins, David M. [Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH (United Kingdom); Jiang, Jun; Britton, T. Benjamin [Department of Materials, Imperial College London, Royal School of Mines, Exhibition Road, London SW7 2AZ (United Kingdom)

    2014-11-03

    Here, we analyse residual stress distributions obtained from various crystal systems using high resolution electron backscatter diffraction (EBSD) measurements. Histograms showing stress probability distributions exhibit tails extending to very high stress levels. We demonstrate that these extreme stress values are consistent with the functional form that should be expected for dislocated crystals. Analysis initially developed by Groma and co-workers for X-ray line profile analysis and based on the so-called “restricted second moment of the probability distribution” can be used to estimate the total dislocation density. The generality of the results are illustrated by application to three quite different systems, namely, face centred cubic Cu deformed in uniaxial tension, a body centred cubic steel deformed to larger strain by cold rolling, and hexagonal InAlN layers grown on misfitting sapphire and silicon carbide substrates.

  1. Measurement of baseline and orientation between distributed aerospace platforms.

    Science.gov (United States)

    Wang, Wen-Qin

    2013-01-01

    Distributed platforms play an important role in aerospace remote sensing, radar navigation, and wireless communication applications. However, besides the requirement of high accurate time and frequency synchronization for coherent signal processing, the baseline between the transmitting platform and receiving platform and the orientation of platform towards each other during data recording must be measured in real time. In this paper, we propose an improved pulsed duplex microwave ranging approach, which allows determining the spatial baseline and orientation between distributed aerospace platforms by the proposed high-precision time-interval estimation method. This approach is novel in the sense that it cancels the effect of oscillator frequency synchronization errors due to separate oscillators that are used in the platforms. Several performance specifications are also discussed. The effectiveness of the approach is verified by simulation results.

  2. Study of the lateral and temporal distributions of particles in the extensive air shower front

    International Nuclear Information System (INIS)

    Toma, G.; Brancus, I. M.; Mitrica, B.; Badea, A. F.; Rebel, H.; Haungs, A.; Sima, O.

    2004-01-01

    To understand the influence of the primary particle (mass and energy) on the development of the Extensive Air Showers (EAS) a study has been performed on simulated events. A number of showers have been simulated using CORSIKA simulation program for different primary particles (p, C, Fe) and different energies (5.62x10 16 and 10 17 eV). The arrival time distributions of particles arriving at ground (detector level) have been studied for different primary energies and masses. Arrival time quartiles have been calculated and compared for different primaries. Arrival time distributions for different distances to shower core and different threshold energies have been compared. To obtain information about the influence of the primary particle on the shape of the lateral distribution of detected shower particles, the simulated lateral density distribution has been approximated with a parametric Lateral Density Function (LDF). The interaction of the shower particles with the detectors has been simulated and the energy deposited in the detectors has been evaluated. This method was used for obtaining the reconstructed (equivalent to the experimental) lateral density distribution, afterwards approximated with the same LDF. To check the quality of the fit and to investigate the sensitivity to fitting conditions, the study was done for three radial ranges, 40-200 m, 350-650 m, 0-1000 m. The total number of particles in the shower front and the truncated number of particles (in the fitting range) have been reconstructed to be compared with the real number of particles from CORSIKA simulations and to investigate the potential use of these parameters in a multiparametric study of extensive air showers. (authors)

  3. Exposure to aerosol and gaseous pollutants in a room ventilated with mixing air distribution

    DEFF Research Database (Denmark)

    Bivolarova, Mariya Petrova; Ondráček, Jakub; Ždímal, Vladimír

    2016-01-01

    The present study investigates the aerosol and gas dispersal in a mechanically ventilated room and the personal exposure to these contaminants. The study was performed in a full-scale climate chamber. The room was air conditioned via mixing total volume ventilation system. The room occupancy was ...... of the thermal manikin were measured. The results showed higher exposure to the contaminants measured at the breathing zone than at the ambient air. The behaviour of the tracer gas and the aerosols was similar.......The present study investigates the aerosol and gas dispersal in a mechanically ventilated room and the personal exposure to these contaminants. The study was performed in a full-scale climate chamber. The room was air conditioned via mixing total volume ventilation system. The room occupancy...... was simulated by a sitting dressed thermal manikin with realistic body shape. During the experiments monodisperse aerosols of three sizes and nitrous oxide tracer gas were generated simultaneously from one location in the room. The aerosol and gas concentrations in the bulk room air and in the breathing zone...

  4. Spectrally resolved measurements of the terahertz beam profile generated from a two-color air plasma

    DEFF Research Database (Denmark)

    Pedersen, Pernille Klarskov; Zalkovskij, Maksim; Strikwerda, Andrew

    2014-01-01

    Using a THz camera and THz bandpass filters, we measure the frequency - resolved beam profile emitted from a two - color air plasma. We observe a frequency - independent emission angle from the plasma .......Using a THz camera and THz bandpass filters, we measure the frequency - resolved beam profile emitted from a two - color air plasma. We observe a frequency - independent emission angle from the plasma ....

  5. Real-time monitoring of emissions with traffic data, simulation and air quality measurements

    NARCIS (Netherlands)

    Klunder, G.A.; Wilmink, I.R.

    2009-01-01

    This paper investigates the possibility to decide when to apply a (dynamic) traffic management measure to improve the air quality or reduce CO2 emissions, based on a limited set of (measured) data. It is expected that a combination of monitoring and modeling is needed for reliable air quality

  6. 30 CFR 75.320 - Air quality detectors and measurement devices.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Air quality detectors and measurement devices... COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.320 Air quality detectors and measurement devices. (a) Tests for methane shall be made by a qualified person with...

  7. A Simple Experiment To Measure the Content of Oxygen in the Air Using Heated Steel Wool

    Science.gov (United States)

    Vera, Francisco; Rivera, Rodrigo; Nunez, Cesar

    2011-01-01

    The typical experiment to measure the oxygen content in the atmosphere uses the rusting of steel wool inside a closed volume of air. Two key aspects of this experiment that make possible a successful measurement of the content of oxygen in the air are the use of a closed atmosphere and the use of a chemical reaction that involves the oxidation of…

  8. Effect of forced-air heaters on perfusion and temperature distribution during and after open-heart surgery

    NARCIS (Netherlands)

    Severens, Natascha M. W.; van Marken Lichtenbelt, Wouter D.; van Leeuwen, Gerard M. J.; Frijns, Arjan J. H.; van Steenhoven, Anton A.; de Mol, Bas A. J. M.; van Wezel, Harry B.; Veldman, Dirk J.

    2007-01-01

    OBJECTIVES: After cardiopulmonary bypass, patients often show redistribution hypothermia, also called afterdrop. Forced-air blankets help to reduce afterdrop. This study explores the effect of forced-air blankets on temperature distribution and peripheral perfusion. The blood perfusion data is used

  9. Effect of forced-air heaters on perfusion and and temperature distribution during and after open-heart surgery

    NARCIS (Netherlands)

    Severens, N.M.W.; Marken Lichtenbelt, van W.; Leeuwen, van G.M.J.; Frijns, A.J.H.; Steenhoven, van A.A.; Mol, de B.A.J.M.; Wezel, H.B.; Veldman, D.J.

    2007-01-01

    Objectives: After cardiopulmonary bypass, patients often show redistribution hypothermia, also called afterdrop. Forced-air blankets help to reduce afterdrop. This study explores the effect of forced-air blankets on temperature distribution and peripheral perfusion. The blood perfusion data is used

  10. Arrival time distributions of electrons in air showers with primary energies above 10 (18)eV observed at 900m above sea level

    Science.gov (United States)

    Kakimoto, F.; Tsuchimoto, I.; Enoki, T.; Suga, K.; Nishi, K.

    1985-01-01

    Detection of air showers with primary energies above 10 to the 19th power eV with sufficient statistics is extremely important in an astrophysical aspect related to the Greisen cut off and the origin of such high energy cosmic rays. Recently, a method is proposed to observe such giant air showers by measuring the arrival time distributions of air-shower particles at large core distances with a mini array. Experiments to measure the arrival time distributions of muons were started in 1981 and those of electrons in early 1983 in the Akeno air-shower array (930 gcm cm squared atmospheric depth, 900m above sea level). During the time of observation, the detection area of the Akeno array was expanded from 1 sq km to sq km in 1982 and to 20 sq km in 1984. Now the arrival time distribution of electrons and muons can be measured for showers with primary energies above 1019eV at large core distances.

  11. Size distribution of air bubbles entering the brain during cardiac surgery.

    Directory of Open Access Journals (Sweden)

    Emma M L Chung

    Full Text Available Thousands of air bubbles enter the cerebral circulation during cardiac surgery, but whether high numbers of bubbles explain post-operative cognitive decline is currently controversial. This study estimates the size distribution of air bubbles and volume of air entering the cerebral arteries intra-operatively based on analysis of transcranial Doppler ultrasound data.Transcranial Doppler ultrasound recordings from ten patients undergoing heart surgery were analysed for the presence of embolic signals. The backscattered intensity of each embolic signal was modelled based on ultrasound scattering theory to provide an estimate of bubble diameter. The impact of showers of bubbles on cerebral blood-flow was then investigated using patient-specific Monte-Carlo simulations to model the accumulation and clearance of bubbles within a model vasculature.Analysis of Doppler ultrasound recordings revealed a minimum of 371 and maximum of 6476 bubbles entering the middle cerebral artery territories during surgery. This was estimated to correspond to a total volume of air ranging between 0.003 and 0.12 mL. Based on analysis of a total of 18667 embolic signals, the median diameter of bubbles entering the cerebral arteries was 33 μm (IQR: 18 to 69 μm. Although bubble diameters ranged from ~5 μm to 3.5 mm, the majority (85% were less than 100 μm. Numerous small bubbles detected during cardiopulmonary bypass were estimated by Monte-Carlo simulation to be benign. However, during weaning from bypass, showers containing large macro-bubbles were observed, which were estimated to transiently affect up to 2.2% of arterioles.Detailed analysis of Doppler ultrasound data can be used to provide an estimate of bubble diameter, total volume of air, and the likely impact of embolic showers on cerebral blood flow. Although bubbles are alarmingly numerous during surgery, our simulations suggest that the majority of bubbles are too small to be harmful.

  12. Air refractometry in a length comparator and the response to changes in the measurement environment

    Energy Technology Data Exchange (ETDEWEB)

    Pieles, H

    1998-11-01

    Two different interference refractometers and one air parameter set-up are simultaneously operated in a temperature-stabilized casing of a length comparator. They allow absolute and relative measurements and calculations, respectively of the refractive index of air to be carried out for continuous interferometric length measurements. Measurement results are presented which were obtained under optimized environmental conditions. In addition, sources of disturbances are described which can significantly influence the measurements of the refractive index of air, and consequently may influence the accuracy of interferometric displacement measurements. (orig.)

  13. Theoretical and Experimental Evaluation of the Temperature Distribution in a Dry Type Air Core Smoothing Reactor of HVDC Station

    Directory of Open Access Journals (Sweden)

    Yu Wang

    2017-05-01

    Full Text Available The outdoor ultra-high voltage (UHV dry-type air-core smoothing reactors (DASR of High Voltage Direct Current systems are equipped with a rain cover and an acoustic enclosure. To study the convective heat transfer between the DASR and the surrounding air, this paper presents a coupled model of the temperature and fluid field based on the structural features and cooling manner. The resistive losses of encapsulations calculated by finite element method (FEM were used as heat sources in the thermal analysis. The steady fluid and thermal field of the 3-D reactor model were solved by the finite volume method (FVM, and the temperature distribution characteristics of the reactor were obtained. Subsequently, the axial and radial temperature distributions of encapsulation were investigated separately. Finally, an optical fiber temperature measurement scheme was used for an UHV DASR under natural convection conditions. Comparative analysis showed that the simulation results are in good agreement with the experimental data, which verifies the rationality and accuracy of the numerical calculation. These results can serve as a reference for the optimal design and maintenance of UHV DASRs.

  14. Age-dependent effective doses for radionuclides uniformly distributed in air

    International Nuclear Information System (INIS)

    Hung, Tran Van

    2014-01-01

    Age-dependent effective doses for external exposure to photons emitted by radionuclides uniformly distributed in air are reported. The calculations were performed for 160 radionuclides, which are important for safety assessment of nuclear facilities. The energies and intensities of photons emitted from radionuclides were taken from the decay data DECDC used for dose calculations. The results are tabulated in the form of effective dose per unit concentration and time (Sv per Bq s m -3 ) for 6 age groups: newborn, 1, 5, 10 and 15 years-old and adult. The effective doses for the adult are also compared to values given in the literature.

  15. Underground measurements of aerosol in radon and thoron progeny activity distributions

    International Nuclear Information System (INIS)

    Khan, A.; Bandi, F.; Phillips, C.R.; Duport, P.

    1990-01-01

    Aerosol and activity distributions of 218 Polonium, 214 Lead, 214 Bismuth, and 212 Lead were determined in two different underground mining environments by means of an optimized time-delay counting scheme and diffusion batteries. In one environment, diesel equipment was operating; and in the other, electrically powered equipment. The two environments differed significantly in total aerosol concentration. In the diesel environment, in particular, aerosol concentrations were unsteady, and fluctuated with vehicular traffic and mining activities. As measured by radon progeny disequilibrium, the age of the air ranged from about 25 to 60 minutes. Thoron working levels were of the same order as radon working levels. In this paper, comparisons are made between the aerosol and activity size distributions in both the diesel and electric mine

  16. Three Mile Island ambient-air-temperature sensor measurements

    International Nuclear Information System (INIS)

    Fryer, M.O.

    1983-01-01

    Data from the ambient-air-temperature sensors in Three Mile Island-Unit 2 (TMI-2) reactor containment building are analyzed. The data were for the period of the hydrogen burn that was part of the TMI-2 accident. From the temperature data, limits are placed on the duration of the hydrogen burn

  17. Millimeter Wave Attenuation in Moist Air: Laboratory Measurements and Analysis.

    Science.gov (United States)

    1984-03-01

    generation of incoherent noise, Mnd wavelengths. (e) scintillitions due to random fluctuations of the medium in space and time. The array of mathematical ...calculations are for observations in the zenith direction free air is very empty. The molecular radius r -1.5 x ICI-4 Lem. groud lvel Coaic aditio of

  18. Nitric oxide density measurements in air and air/fuel nanosecond pulse discharges by laser induced fluorescence

    International Nuclear Information System (INIS)

    Uddi, M; Jiang, N; Adamovich, I V; Lempert, W R

    2009-01-01

    Laser induced fluorescence is used to measure absolute nitric oxide concentrations in air, methane-air and ethylene-air non-equilibrium plasmas, as a function of time after initiation of a single pulse, 20 kV peak voltage, 25 ns pulse duration discharge. A mixture of NO and nitrogen with known composition (4.18 ppm NO) is used for calibration. Peak NO density in air at 60 Torr, after a single pulse, is ∼8 x 10 12 cm -3 (∼4.14 ppm) occurring at ∼250 μs after the pulse, with decay time of ∼16.5 ms. Peak NO atom mole fraction in a methane-air mixture with equivalence ratio of ψ = 0.5 is found to be approximately equal to that in air, with approximately the same rise and decay rate. In an ethylene-air mixture (also with equivalence ratio of ψ = 0.5), the rise and decay times are comparable to air and methane-air, but the peak NO concentration is reduced by a factor of approximately 2.5. Spontaneous emission measurements show that excited electronic states N 2 (C 3 Π) and NO(A 2 Σ) in air at P = 60 Torr decay within ∼20 ns and ∼1 μs, respectively. Kinetic modelling calculations incorporating air plasma kinetics complemented with the GRI Mech 3.0 hydrocarbon oxidation mechanism are compared with the experimental data using three different NO production mechanisms. It is found that NO concentration rise after the discharge pulse is much faster than predicted by Zel'dovich mechanism reactions, by two orders of magnitude, but much slower compared with reactions of electronically excited nitrogen atoms and molecules, also by two orders of magnitude. It is concluded that processes involving long lifetime (∼100 μs) metastable states, such as N 2 (X 1 Σ,v) and O 2 (b 1 Σ), formed by quenching of the metastable N 2 (A 3 Σ) state by ground electronic state O 2 , may play a dominant role in NO formation. NO decay, in all cases, is found to be dominated by the reverse Zel'dovich reaction, NO + O → N + O 2 , as well as by conversion into NO 2 in a reaction

  19. Nitric oxide density measurements in air and air/fuel nanosecond pulse discharges by laser induced fluorescence

    Science.gov (United States)

    Uddi, M.; Jiang, N.; Adamovich, I. V.; Lempert, W. R.

    2009-04-01

    Laser induced fluorescence is used to measure absolute nitric oxide concentrations in air, methane-air and ethylene-air non-equilibrium plasmas, as a function of time after initiation of a single pulse, 20 kV peak voltage, 25 ns pulse duration discharge. A mixture of NO and nitrogen with known composition (4.18 ppm NO) is used for calibration. Peak NO density in air at 60 Torr, after a single pulse, is ~8 × 1012 cm-3 (~4.14 ppm) occurring at ~250 µs after the pulse, with decay time of ~16.5 ms. Peak NO atom mole fraction in a methane-air mixture with equivalence ratio of phiv = 0.5 is found to be approximately equal to that in air, with approximately the same rise and decay rate. In an ethylene-air mixture (also with equivalence ratio of phiv = 0.5), the rise and decay times are comparable to air and methane-air, but the peak NO concentration is reduced by a factor of approximately 2.5. Spontaneous emission measurements show that excited electronic states N2(C 3Π) and NO(A 2Σ) in air at P = 60 Torr decay within ~20 ns and ~1 µs, respectively. Kinetic modelling calculations incorporating air plasma kinetics complemented with the GRI Mech 3.0 hydrocarbon oxidation mechanism are compared with the experimental data using three different NO production mechanisms. It is found that NO concentration rise after the discharge pulse is much faster than predicted by Zel'dovich mechanism reactions, by two orders of magnitude, but much slower compared with reactions of electronically excited nitrogen atoms and molecules, also by two orders of magnitude. It is concluded that processes involving long lifetime (~100 µs) metastable states, such as N2(X 1Σ,v) and O2(b 1Σ), formed by quenching of the metastable N2(A 3Σ) state by ground electronic state O2, may play a dominant role in NO formation. NO decay, in all cases, is found to be dominated by the reverse Zel'dovich reaction, NO + O → N + O2, as well as by conversion into NO2 in a reaction of NO with ozone.

  20. Trends of multiple air pollutants emissions from residential coal combustion in Beijing and its implication on improving air quality for control measures

    Science.gov (United States)

    Xue, Yifeng; Zhou, Zhen; Nie, Teng; Wang, Kun; Nie, Lei; Pan, Tao; Wu, Xiaoqing; Tian, Hezhong; Zhong, Lianhong; Li, Jing; Liu, Huanjia; Liu, Shuhan; Shao, Panyang

    2016-10-01

    Residential coal combustion is considered to be an important source of air pollution in Beijing. However, knowledge regarding the emission characteristics of residential coal combustion and the related impacts on the air quality is very limited. In this study, we have developed an emission inventory for multiple hazardous air pollutants (HAPs) associated with residential coal combustion in Beijing for the period of 2000-2012. Furthermore, a widely used regional air quality model, the Community Multi-Scale Air Quality model (CMAQ), is applied to analyze the impact of residential coal combustion on the air quality in Beijing in 2012. The results show that the emissions of primary air pollutants from residential coal combustion have basically remained the same levels during the past decade, however, along with the strict emission control imposed on major industrial sources, the contribution of residential coal combustion emissions to the overall emissions from anthropogenic sources have increased obviously. In particular, the contributions of residential coal combustion to the total air pollutants concentrations of PM10, SO2, NOX, and CO represent approximately 11.6%, 27.5%, 2.8% and 7.3%, respectively, during the winter heating season. In terms of impact on the spatial variation patterns, the distributions of the pollutants concentrations are similar to the distribution of the associated primary HAPs emissions, which are highly concentrated in the rural-urban fringe zones and rural suburb areas. In addition, emissions of primary pollutants from residential coal combustion are forecasted by using a scenario analysis. Generally, comprehensive measures must be taken to control residential coal combustion in Beijing. The best way to reduce the associated emissions from residential coal combustion is to use economic incentive means to promote the conversion to clean energy sources for residential heating and cooking. In areas with reliable energy supplies, the coal used