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At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1985

Formulation of cosmic-ray solar daily variation and its seasonal variation, produced from generalized stationary anisotropy of solar origin

In previous papers, a formulation was presented of cosmic ray daily variations produced from solar anisotropies stationary through a year, and also of their annual (or seasonal) modulation caused by the annual variation of the rotation axis of the Earth relative to that of the Sun. These anisotropies are symmetric for an arbitrary rotation around an axis. From observations of the tri-diurnal variation, it has been suggested that solar anisotropies also contain some axis-asymmetric term of the third order with respect to the IMF-axis. This suggestion has recently found support in a theoretical study by Munakata and Nagashima. According to their results, the terms of axis-asymmetry with respect to IMF-axis appear also in the 2nd order anisotropy, together with some different kinds of axis-symmetric terms. The contribution of these anisotropies to the daily variation is different from that of those discussed previously. The above mentioned formulation is extended to a case of a generalized anisotropy.

Tatsuoka, R.↗
DOE OSTI2018

Main components of PM10 in an area influenced by a cement plant in Catalonia, Spain: Seasonal and daily variations

Highlights: • Constituents and main components of airborne PM{sub 10} near a cement plant were studied. • A clear seasonality was found, with higher levels in winter. • A daily pattern was not observed, when comparing weekdays and weekends. • Road traffic had a significant contribution to PM{sub 10} levels. Particulate matter (PM) composition has a key role in a wide range of health outcomes, such as asthma, chronic obstructive pulmonary disease, lung cancer, cardiovascular disease, and death, among others. Montcada i Reixac, a municipality located in the Barcelona metropolitan area (Catalonia, Spain), for its location and orography, is an interesting case- study to investigate air pollution. The area is also characterized by the presence of different industrial emission sources, including a cement factory and a large waste management plant, as well as an intense traffic. In this study, PM{sub 10} levels, trace elements, ions, and carbonaceous particles were determined for a long time period (2013–2016) in this highly polluted area. PM{sub 10} samples were collected during six consecutive days in two campaigns (cold and warm) per year. A number of elements (As, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Hg, Ho, K, La, Li, Hg, Mg, Mn, Mo, Nb, Nd, Ni, Pb, Pr, Rb, Sb, Sc, Se, Sm, Sn, Sr, Tb, Th, Ti, Tl, U, V, W, Y, Yb, and Zr), ions (Cl{sup -}, SO{sub 4}{sup 2-}, NO{sub 3}{sup -}, and NH{sub 4}{sup +}), and carbonaceous content (total carbon, organic plus elemental carbon, and CO{sub 3}{sup 2-}), were analysed. These data were used to identify the PM{sub 10} main components: mineral matter, sea spray, secondary inorganic aerosols, organic matter plus elemental carbon, trace elements or indeterminate fraction. Although a clear seasonality (cold vs. warm periods) was found, there were no differences between working days and weekends. Obviously, the cement plant influences the surrounding environment. However, no differences in trace elements related with the cement plant activity (Al, Ca, Ni and V) between weekdays and weekends were noted. However, some traffic-related elements (i.e., Co, Cr, Mn, and Sb) showed significantly higher concentrations in weekdays.

54 ENVIRONMENTAL SCIENCES↗
NASA NTRS1972

Average daily variations in the magnetic field as observed by ATS-5

Hourly averages of the magnetic field components are determined and analyzed using the measurements, by the magnetic field monitor (MFM) aboard the ATS-5 satellite. The data covering the time period of September 1969 through September 1971 are sorted and analyzed for various Kp values, geomagnetic latitude of the subsolar point, and local time. Local time variations are harmonically analyzed, and amplitudes and phases are given up to the fourth harmonic.

Skillman, T. L.↗
NASA NTRS1974

Average daily variations in the magnetic field as observed by ATS-5

Hourly averages of the magnetic field components are determined and analyzed using the measurements of the magnetic field monitor aboard the ATS-5. The data covering the time period of September 1969 through September 1971 are sorted and analyzed for various Kp values, geomagnetic latitude of the subsolar point, and local time. Local time variations are harmonically analyzed, and amplitudes and phases are given up to the fourth harmonic.

Skillman, T. L.↗
NASA NTRS1974

Individual radiosensitivity and its daily variations

The effectiveness of determining individual radiosensitivity of rats by total gas exchange measurements, studies of Na/K content in urine, and the reaction of leukocytes to intra-abdominal administration of epinephrine, was studied. The most indicative results of predicting individual reaction to radiation were obtained by the leukocyte reaction to epinephrine load; however, changes in the leukocyte content of peripheral blood after epinephrine administration depended on the initial level during the day.

Druzhinin, Y. N.↗
NASA NTRS1985

The first three harmonics of solar daily variation caused by the diffusive propagation of galactic cosmic rays through the heliosphere

Some results for the first three harmonics derived from the simulation of diffusion convection of galactic cosmic rays is presented. Also, some dependences of the results to the modulation parameters are presented. The results are discussed in comparison with observations and with the former studies of higher order anisotropy. In addition to this, the existence is suggested of the IMF-sense-dependent anisotropy of higher order.

Munakata, K.↗
NASA NTRS1985

Solar wind velocity and daily variation of cosmic rays

Recently parameters applicable to the solar wind and the interplanetary magnetic field (IMF) have become much better defined. Superior quality of data bases that are now available, particularly for post-1971 period, make it possible to believe the long-term trends in the data. These data are correlated with the secular changes observed in the diurnal variation parameters obtained from neutron monitor data at Deep River and underground muon telescope data at Embudo (30 MEW) and Socorro (82 MWE). The annual mean amplitudes appear to have large values during the epochs of high speed solar wind streams. Results are discussed.

Ahluwalia, H. S.↗
DOE OSTI2012

Assessing Energy Impact of Plug-In Hybrid Electric Vehicles: Significance of Daily Distance Variation over Time and Among Drivers

Accurate assessment of the impact of plug-in hybrid electric vehicles (PHEVs) on petroleum and electricity consumption is a necessary step toward effective policies. Variations in daily vehicle miles traveled (VMT) over time and among drivers affect PHEV energy impact, but the significance is not well understood. This paper uses a graphical illustration, a mathematical derivation, and an empirical study to examine the cause and significance of such an effect. The first two methods reveal that ignoring daily variation in VMT always causes underestimation of petroleum consumption and overestimation of electricity consumption by PHEVs; both biases increase as the assumed PHEV charge-depleting (CD) range moves closer to the average daily VMT. The empirical analysis based on national travel survey data shows that the assumption of uniform daily VMT over time and among drivers causes nearly 68% underestimation of expected petroleum use and nearly 48% overestimation of expected electricity use by PHEVs with a 40-mi CD range (PHEV40s). Also for PHEV40s, consideration of daily variation in VMT over time but not among drivers similar to the way the utility factor curve is derived in SAE Standard SAE J2841 causes underestimation of expected petroleum use by more than 24% and overestimation of expected electricity use by about 17%. Underestimation of petroleum use and overestimation of electricity use increase with larger-battery PHEVs.

02 PETROLEUM↗
NASA NTRS1979

Neutral thermospheric composition and thermal structure

A review of the published experimental works of the past four years is presented. Since 1975, satellite and ground based programs produced new data on the composition and structure of the thermosphere, including the first extensive measurements of a number of minor constituents. The new data were incorporated in a number of semiempirical models which provided an increasingly accurate picture of thermospheric variations. Empirical modelling is considered, followed by solar activity variations, daily variations, magnetic storm variations, measurements of molecular oxygen and minor species, and miscellaneous temperature and density determinations. The concepts of global circulation patterns driven by solar radiation, magnetospheric energy, and momentum sources, and wave sources in the lower atmosphere, and the accompanying redistribution of minor species are outlined.

Hedin, A. E.↗
NASA NTRS1978

Analysis of daily latitude variations

The daily latitude measurements of the International polar motion service are analyzed. The results indicate that the annual polar oscillation is probably due to local phenomena with amplitudes varying from 0.05 to 0.15 min. Within the resolution of the residuals (150 cm), there is no indication of the sharp changes which might be associated with earthquake effects. Then, applying Schuster's test to a periodogram of the residuals indicates that there are probably several processes occurring at amplitudes between 0.007 and 0.03 min whose solution awaits a more precise measurement technique.

Graber, M. A.↗
NASA NTRS1979

Analysis of daily latitude variations

The daily latitude measurements of the International Polar Motion Service are analyzed. The annual oscillation in the data was modeled by separate oscillations in each observatory's latitude data. The separate oscillations varied in amplitude from 0.05 sec to 0.15 sec with standard deviations of about 0.007 sec. Within the resolution of the latitude residuals (150 cm), there is no indication of the sharp changes which might be associated with earthquake effects. Then, applying Schuster's test to a periodogram of the residuals indicates that there are probably several processes occurring at amplitudes between 0.007 sec and 0.03 sec whose solution awaits a more precise measurement technique.

Graber, M. A.↗
NASA NTRS1976

Comparisons of measured and theoretical thermospheric daily composition variations

A comparison of the diurnal component of the daily variation in the neutral composition data from the San Marco 3 Nace (Neutral Atmospheric Composition Experiment) mass spectrometer at 220, 250, and 280 km, the OGO-6 model data at 450 km, rocket measurements of nitrogen between 140 and 300 km, and the two-constituent theoretical model of Mayr and Volland (1973) gives good agreement for molecular nitrogen and atomic oxygen. The Nace and rocket measurements overlap in altitude, and there is good agreement in the amplitude and phase of the diurnal and semidiurnal components for molecular nitrogen. The helium diurnal amplitude and phase of the theoretical model are in fair agreement with the Nace results, while the amplitude from the OGO-6 model at 450 km is much larger than the model predicts, a result suggesting that the OGO-6 model diurnal amplitude may be overestimated as the result of an incomplete separation of local-time and seasonal effects.

Kasprzak, W. T.↗