Relevant bibliographies by topics / Line emission study

Academic literature on the topic 'Line emission study'

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Published: 10 December 2022
Last updated: 29 January 2023

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Journal articles on the topic "Line emission study"

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Hang, Hengrong, and Jianping Xia. "Recent study of emission line star 3G71." Chinese Science Bulletin 43, no. 6 (March 1998): 470–73. http://dx.doi.org/10.1007/bf02883811.

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Nepal, Sangeet, Parth Mahapatra, Sagar Adhikari, Sujan Shrestha, Prakash Sharma, Kundan Shrestha, Bidya Pradhan, and Siva Puppala. "A Comparative Study of Stack Emissions from Straight-Line and Zigzag Brick Kilns in Nepal." Atmosphere 10, no. 3 (March 1, 2019): 107. http://dx.doi.org/10.3390/atmos10030107.

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Nepal has approximately 1000 operational brick kilns, which contribute significantly to ambient air pollution. They also account for 1.81% of the total bricks produced in the South Asian region. Little is known about their emissions, which are consequently not represented in regional/global emission inventories. This study compared emissions from seven brick kilns. Four were Fixed Chimney Bull’s Trench Kilns (FCBTKs) and three were Induced-Draught Zigzag Kilns (IDZKs). The concentrations of carbon dioxide (CO2), sulfur dioxide (SO2), black carbon (BC), and particulate matter (PM) with a diameter less than 2.5 µm (PM2.5) were measured. The respective emission factors (EFs) were estimated using the carbon mass balance method. The average fuel-based EF for CO2, SO2, PM2.5, and BC were estimated as 1633 ± 134, 22 ± 22, 3.8 ± 2.6 and 0.6 ± 0.2 g per kg, respectively, for all FCBTKs. Those for IDZKs were 1981 ± 232, 24 ± 22, 3.1 ± 1, and 0.4 ± 0.2 g per kg, respectively. Overall, the study found that converting the technology from straight-line kilns to zigzag kilns can reduce PM2.5 emissions by ~20% and BC emissions by ~30%, based on emission factor estimates of per kilogram of fuel. While considering per kilogram of fired brick, emission reductions were approximately 40% for PM2.5 and 55% for BC, but this definitely depends on proper stacking and firing procedures.
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Ballereau, D., J. Chauville, A. Garcia, and J. Zorec. "Study of the HeI λ4471 line-profile of Be stars." Symposium - International Astronomical Union 162 (1994): 259–60. http://dx.doi.org/10.1017/s0074180900214988.

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In this paper we study the veiling effect and the strength of an extra emission-like component filling partially the HeI λ4471 line of Be stars. It is shown that this component is roughly correlated with the emission in the continuum and in the Hγ line.
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Amaro, Nuno, João Saragoça, Ricardo Cartaxo, Wei Yang, and Ren Yi. "IEEE 1901.1 Power Line Communication electromagnetic emission study." Journal of Physics: Conference Series 1983, no. 1 (July 1, 2021): 012059. http://dx.doi.org/10.1088/1742-6596/1983/1/012059.

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Alonso-Herrero, Almudena. "A Near-Infrared Study of Emission-Line Galaxies." Publications of the Astronomical Society of the Pacific 109 (January 1997): 69. http://dx.doi.org/10.1086/133860.

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Xiao, Hubing, Junhui Fan, Zhihao Ouyang, Liangjun Hu, Guohai Chen, Liping Fu, and Shaohua Zhang. "An Extensive Study of Blazar Broad Emission Line: Changing-look Blazars and the Baldwin Effect." Astrophysical Journal 936, no. 2 (September 1, 2022): 146. http://dx.doi.org/10.3847/1538-4357/ac887f.

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Abstract It is known that the blazar jet emissions are dominated by nonthermal radiation, while the accretion disk jets are normally dominated by thermal emission. In this work, our aim is to study the connection between the two types of emission by investigating the correlation between the blazar emission-line intensity property, which embodies the nature of an accretion disk, and the γ-ray flux property, which is the representative of jet emission. We compiled a sample of 656 blazars with available emission-line equivalent widths (EWs), the GeV γ-ray flux, and the spectral energy distribution (SED) information from the literature. In this work, we found 55 previous blazar candidates of uncertain types (BCUs) that are now identified as flat-spectrum radio quasars (FSRQs), and found 52 “changing-look” blazars based on their EWs, 45 of which are newly confirmed. These changing-look blazars have a larger accretion ratio ( M ̇ / M ̇ Edd ) than BL Lacertae (BL Lac) objects. In addition, we suggest that the lower synchrotron peak blazars (LSPs) could be the source of changing-look blazars because 90.7% of the changing-look blazars in this work are confirmed as LSPs. An anticorrelation between EW and continuum intensity, the so-called global “Baldwin effect” (BEff), has been confirmed. We suggest that the steeper global BEff observed for the blazar than for radio-quiet active galactic nuclei (RQ-AGNs) is caused by the inverse Compton scattering of broad-emission-line photons. This interpretation is further supported by the positive correlation between the emission-line EW and intrinsic inverse Compton luminosity.
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Zhang, Yan, and Chang Wang. "Study on the Relationship between the Energy Carbon Emission and Economic Growth in Hebei Province." Applied Mechanics and Materials 623 (August 2014): 310–16. http://dx.doi.org/10.4028/www.scientific.net/amm.623.310.

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This article simply reviewed the carbon emission situation in Hebei province from 1996 to 2011, and tried to use environmental Kuznets curve to analysis the impact of the economic growth of CO2 emissions on the energy consumption. The regression results show that CO2 emissions and economic growth in line with the environmental Kuznets curve inverted U-shaped, but it is in the left hemisphere of the curve, namely, as the growth of the economy, the CO2 emissions will continue to increase, so the carbon emission reduction work in Hebei province is still very heavy, we should change the energy consumption situation actively in the environment, adjust the industrial structure, develop new technology vigorously, and promote the innovation of emission reduction.
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Tomberlin, Kristen E., Richard Venditti, and Yuan Yao. "Life cycle carbon footprint analysis of pulp and paper grades in the United States using production-line-based data and integration." BioResources 15, no. 2 (April 7, 2020): 3899–914. http://dx.doi.org/10.15376/biores.15.2.3899-3914.

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Greenhouse gas (GHG) emission levels are causing concern as climate change risks are growing, emphasizing the importance of GHG research for better understanding of emission sources. Previous studies on GHG emissions for the pulp and paper industry have ranged in scope from global to regional to site-specific. This study addresses the present knowledge gap of how GHG emissions vary among paper grades in the US. A cradle-to-gate life cycle carbon analysis for 252 mills in the US was performed by integrating large datasets at the production line level. The results indicated that one metric ton of paper product created a production weighted average of 942 kg of carbon dioxide equivalent (kg CO2eq) of GHG emissions. Greenhouse gas emissions varied by pulp and paper grade, from 608 kg CO2eq per metric ton of product to 1978 kg CO2eq per metric ton of product. Overall, fuels were the greatest contributor to the GHG emissions and should be the focus of emission reduction strategies across pulp and paper grades.
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Fogel, Jeffrey, Orsola De Marco, and George Jacoby. "The Weak Emission Line Stars." Symposium - International Astronomical Union 209 (2003): 235–36. http://dx.doi.org/10.1017/s0074180900208589.

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In this paper, we study the evolution of the weak emission line central stars of planetary nebula (WELS), which are similar to the H-deficient Wolf-Rayet central stars except for systematically weaker emission lines. Our attempts at finding an evolutionary sequence for the WELS similar to what was established for Wolf-Rayet central stars, were unsuccessful. No correlation was found between any of the analysed quantities: emission and absorption line fluxes or stellar and nebular parameters from the literature. It does appear, however, that WELS have intermediate stellar temperatures (30–80 kK), and do not reside in the middle of Type I planetary nebulae, possibly indicating lower mass precursors.
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Xia, Lifang, Sangeeta Malhotra, James Rhoads, Norbert Pirzkal, Zhenya Zheng, Gerhardt Meurer, Amber Straughn, Norman Grogin, and David Floyd. "SPECTROSCOPIC STUDY OF THEHST/ACS PEARS EMISSION-LINE GALAXIES." Astronomical Journal 141, no. 2 (January 13, 2011): 64. http://dx.doi.org/10.1088/0004-6256/141/2/64.

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Dissertations / Theses on the topic "Line emission study"

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Robinson, A. "A study of emission line variability in active galactic nuclei." Thesis, University of Manchester, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356433.

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Jarad, Majeed M. "A spectroscopic study of some early-type emission-line stars." Thesis, University of St Andrews, 1986. http://hdl.handle.net/10023/14418.

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Spectroscopic observations of 18 of the brighter Be and 0e stars in the Northern Hemisphere have been presented in this project. About 900 spectrograms were secured and measured using the more objective numerical technique (REDUCE and VCROSS) to obtain as many accurate radial velocities as possible for these stars. The analysis of these measurements has demonstrated clearly, that most of these early-type stars are indeed variable in radial velocity, while a real periodicity in the radial velocities of some of the programme stars is found. The long-term periodicities were attributed to the binary nature, while the short ones could be ascribed to the pulsation phenomenon. Orbital elements are determined for four newly discovered binary systems, and improved orbits are determined for four known binaries. Five other stars display short time-scale periodicity (less than 1.5 days) attributable to radial or non-radial pulsation, whilst three variables show little evidence for periodicity. Only two stars are found to have constant radial velocities. A brief summary of the properties of Be stars and all the available models to explain the Be phenomenon is presented in chapter one. Chapter two contains a brief description of the observing equipment and the techniques used. The reasons for selecting the programme stars are given in the same chapter. A complete explanation of the measuring technique used in this investigation is given in chapter three. In chapter four, all the analyses and the results for each star are given individually, while a discussion of previous work on these stars appears in the relevant sections. The final chapter contains a discussion of the results from this study together with an analysis of the energy distributions of the programme stars, compiled by the author from published fluxes and photometry from the ultraviolet to the infra-red parts of the electromagnetic spectrum. Some consideration of future work to be done on these types of stars is also given.
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Younes, George. "Complete X-ray study of low ionization nuclear emission line regions showing broad Hα emission (LINER 1s) and their spectral energy distribution." Strasbourg, 2011. http://www.theses.fr/2011STRA6088.

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Cette thèse concerne l'étude des noyaux actifs de galaxies (AGN) de faible luminosité dans l'univers proche, principalement peuplé par les "Low Ionization Nuclear Emission-line Regions" (LINERs) galaxies. L'étude a été basée sur un échantillon de LINERls montrant une détection robuste de raie large en émission Halpha, une propriété typique des AGN lumineux de type 1. J'ai étudié le mode d'accrétion et les processus radiatifs de ces LINER 1 s en examinant leurs propriétés en rayons X et multi-Iongueurs d'onde (distribution spectrale d'énergie, SED), et en les comparant t celles des AGN lumineux (Seyferts et quasars) et des binaires X. Les différences des propriétés en rayons X de cet échantillon par rapport aux AGN lumineux (variabilité sur des courtes échelles de temps rare, absence de la raie d'émission Fe Kalpha t 6. 4 keV, et anticorrélation de l'indice de la loi de puissance en rayons X avec le rapport d'Eddington) indiquent probablement la présence d'un mode d'accrétion et radiatif différent entre ces deux classes d'objets, c. -t. -d. Un processus radiatif RIAF/jet pour les LINER Is. A une luminosité en rayons X donnée, la SED de ces LINER 1 s, construite avec des flux simultanées en rayons X et UV, (1) ressemble dans le domaine radio t celles des AGN radio-émettrices (rapport du flux radio sur rayons X, =-1. 17), et (3) montre une luminosité bomométrique d'au moins deux ordres de grandeur plus faible que les AGN lumineuses. Ces propriétés multi-Iongueurs d'onde de ces LINERls sont également probablement compatibles avec un processus radiatif RIAF/jet
This thesis focuses on the faint end of the active galactic nuclei (AGN) luminosity function in the nearby universe, mainly populated by AGN-powered Low Ionization Nuclear Emission-line Regions (LINERs). The study was based on a LINERls sample anSllyzed showing a definite detection of a broad Halpha emission, a typical property of luminous type 1 AGN. 1 have investigated the accretion mode and radiative processes ofthese AGN-powered LINERls based on their X-ray and multi-wavelength (spectral energy distribution, SED) properties, and 1 have compared them to those ofluminous AGN (Seyfert galaxies and quasars) and X-ray binaries. The dissimilarities in the X-ray properties ofthis sample compared to luminous AGN (rare short timescale variability, no Fe Kalpha emission line at 6. 4 keV, ~nd the anticorrelation of the X-ray powerlaw index with the Eddington ratio) point toward probably a different accretion and radiative process in these two classes, i. E. A RIAF/jet radiative process in LINER ls. The SED ofthese LINER ls with simultaneous UV and X-ray fluxes, at a given X-ray luminosity, (1) resembles the SED ofradio-loud AGN in the radio band (mean radio-to-X-ray flux ratio, =-1. 17), and (3) displays bolometric luminosity of at least two orders of magnitude lower than luminous AGN. Again, the multi-wavelength properties ofthese LINERls are most likely consistent with a RIAF/jet radiative rocess
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Holt, Joanna. "An observational study of the emission line systems in compact radio sources." Thesis, University of Sheffield, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.419256.

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Ferreira, João Pedro de Jesus. "A broad-band study of the evolving emission-line properties of galaxies." Thesis, University of Edinburgh, 2018. http://hdl.handle.net/1842/28717.

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This thesis describes a new approach to the study of high-redshift star-formation and its environments that can be applied to large high-redshift surveys. Instead of relying on spectroscopy or narrow-band photometry to study galaxy line emission in detail, the properties of large emission line galaxy (ELG)populations are estimated from broadband photometry by measuring colour-residuals against colours drawn from a set of line-free stochastic burst models-based on (Bruzual & Charlot, 2003). Simulated star-formation histories drawn from semi-analytic and adaptive-mesh-refinement codes were converted into mock galaxy colours, but neither could-span the range of observed galaxy colours at high redshift. Instead, an existing set of exponentially declining star-formation models with stochastic bursts was used, because it closely spanned the range in observed galaxy colours in the bandsthat were line-free at each redshift. Small colour offsets were measured between the models and the observations, corresponding to the equivalent widths (EWs)of Hα, [OIII] and [OII]. In this way, I measure the rest-frame Equivalent Widths of the Hα, [OIII]and [OII] emission lines as they are redshifted through all filters from CANDELS(near-continuous U to 4.5μm coverage) for a large sample of galaxies from z=0.1up to z=5. This approach relies solely on the line-free models, a set of existing reliable photometric redshifts, and a colour cut (B−K < 2 or equivalent) to select only the dust-free young objects (the majority of identified emission-line galaxies). Once correctly identified, I apply this method to the CANDELS-UDS photometry to characterise the properties of Emission-Line Galaxies (ELGs) through these lines. I find that in this sample the Hα and [OIII] ELG fraction with EW > 150Årises from < 5% at z < 1 up to 40% at z > 2. The co-moving ELG density rises from 5 to 30 ×10 −4 /Mpc −3 at z=2.3. The evolution of median Hα EW with redshift is consistent with results from HiZELS and 3D-HST yielding median EW ∼ M 0.25 (1+z) 1.75 up to z=2.3, from which it departs to values of 450Å atz=4.3. [OIII] remains weaker than Hα for z < 3 and matches its values above that redshift. [OIII] also displays a larger fraction of extreme EWs than Hα. [OII], while correctly identified, never becomes as extreme as the other two lines lines, even when corrected for the evolving continuum. This is evidence of an increasing [OIII]/[OII] ratio with increasing z through-out this sample. While these results agree with spectroscopic and narrow-band surveys, the use of the deeper broadband filter coverage enables a systematic measurement of the increasingly prevalent high EWs ( > 500Å) in galaxies at every redshift spanning the 10 8 to 10 10.5 M range. Subsequently, this method was applied to all the other CANDELS fields (GOODS-South and North, COSMOS and EGS) and further corroborates these results. These results further show that EW dependence on mass is steeper for [OIII] than for Hα. Line EWs are then converted into luminosities for the three lines and fitting formulas are obtained, displaying L Hα ∼(1+z) 3.2 M 0.45−0.6log(1+z), with similar results for the other lines. L Hα is converted into star-formation rate and specific star-formation rate (sSFR). sSFR at low-z aligns approximately with the main sequence (with a steeper dependence in mass), but at high-redshift sSFR remains above the main sequence by a factor of 2 and rising towards medians SFR=100/Gyr around log(M/M )=9, showing a departure of the main sequence of star formation at lower masses log(M/M ) < 9.5. The SFRD of ELGs is 1% at low redshift, but rises to 30% at z=4.5. The L [OIII] /L Hα ratio is used to estimate L [OIII] /L Hβ and the ionization parameter q, for which the median atz > 0.5 stays approximately constant at 10 8 cm/s, and increases with mass. Using the L [OIII] /L [OII] ratio and q, median metallicity is shown to be sub-solar, and can be tentatively estimated for z > 0.5 to be Z/Z ∼0.3. The errors are large, but this could also mean a large range in metallicity from Z to 0.1Z . L [OIII] /L [OII] rises with sSFR as shown in the literature. This method shows great potential to survey emission-line-derived physical quantities for large galaxy populations with a low computational footprint, which could be particularly useful for pixel-by-pixel EW imaging. It is also flexibile, which allows it to be applied to any future deep multi-broadband fields.
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Magno, Macon, and Richard Ignace. "A Study of the H-alpha Emission Line Shape in Beta Lyrae." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/asrf/2018/schedule/150.

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Beta Lyrae is a complex binary star system with a 13-day orbital period containing two massive stars that are in the process of mass reversal accretion. The primary star is the higher mass star which is gaining mass from the secondary star. This reversal mass accretion causes gas to build and form a disk around the primary star. The disk is geometrically and optically thick. Previous interferometric studies in Optical and Infrared wavelengths have shown that a bipolar jet exists in the system and suggest that the jet contributes to the H-alpha emission. Meanwhile, other studies have suggested that the disk contributes to the H-alpha emission. We have taken into account various factors to model the emission of H-alpha from Beta Lyrae. The observed profile is double-peaked and varies with orbital phase. We found that the jet produces a single-peak for H-alpha emission. Meanwhile, the disk produces a double-peak for H-alpha emission if it is based on Keplerian motion. We use our model to interpret the observed H-alpha emission variations in the line shape with orbital phase.
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Melnick, Ian Mark. "A diagnostic study of chlorine X-ray line emission from the compass-D tokamak." Thesis, University College London (University of London), 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308930.

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Nobukawa(Kawabata), Kumiko. "X-ray Study of Neutral Iron Line Emission in the Galactic Ridge: Contribution of Low-Energy Cosmic Rays." 京都大学 (Kyoto University), 2016. http://hdl.handle.net/2433/215310.

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Inui, Tatsuya. "X-ray study of the variable neutral iron line emission of the Sgr B2 complex in the galactic center region." 京都大学 (Kyoto University), 2008. http://hdl.handle.net/2433/136867.

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Nelson, Keith Phillip. "An Arcminute-Resolution Imaging Study of the H-alpha & [S II] Emission of the ISM from the Local Perseus Arm Using the Virginia Tech Spectral-Line Survey." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/28638.

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The Virginia Tech Spectral-Line Survey (VTSS) is a series of 10-degree wide, arcminute-resolution images of the warm ionized interstellar medium (WIM) within the Milky Way for declinations greater than -15 degrees. The Wisconsin Hydrogen-Alpha Mapper (WHAM) studies the kinematics and distribution of this same material on an angular scale of one degree. Comparing the spatially-resolved images of the VTSS with WHAM's high spectral resolution images shows that the ISM's characteristics appear to be very similar at both degree and arcminute scales --- we see similar structures, and notice the same [S II]/H-alpha trend between those structures at both degree and arcminute scales. VTSS fields show three basic types of structures --- compact clouds with diameters greater than several degrees, those that are 1-degree or less in diameter, and extended filaments that differ from the clouds by spanning several degrees in length but having thicknesses of only a few tens of arcminutes. The latter two morphological types cannot be observed by WHAM. Additionally, VTSS data confirms that the [S II] intensity values are directly proportional to H-alpha intensities, a result that is also observed at degree resolutions. Finally, VTSS data show that [S II]/H-alpha ratios are, on average, nearly six times higher in the filaments. This would indicate that collisional excitation of singly-ionized sulfur ions is the dominant emission source within filaments. In clouds, the lower [S II]/H-alpha values observed are evidence that the H-alpha recombination line of photo-excited neutral hydrogen dominates. Because automating the VTSS was a key part of obtaining many of the images used in this project, I begin with a discussion of general observatory automation. I then address the specific processes and techniques used in automating the VTSS before discussing data collection and reduction techniques.
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Books on the topic "Line emission study"

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Audley, Michael Damian. A broad-band spectral and timing study of the X-ray binary system Centaurus X-3. Greenbelt, Md: Laboratory for High Energy Astrophysics, National Aeronautics and Space Administration, Goddard Space Flight Center, 1998.

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Audley, Michael Damian. A broad-band spectral and timing study of the X-ray binary system Centaurus X-3. Greenbelt, Md: Laboratory for High Energy Astrophysics, National Aeronautics and Space Administration, Goddard Space Flight Center, 1998.

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Audley, Michael Damian. A broad-band spectral and timing study of the X-ray binary system Centaurus X-3. Greenbelt, Md: Laboratory for High Energy Astrophysics, National Aeronautics and Space Administration, Goddard Space Flight Center, 1998.

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Audley, Michael Damian. A broad-band spectral and timing study of the X-ray binary system Centaurus X-3. Greenbelt, Md: Laboratory for High Energy Astrophysics, National Aeronautics and Space Administration, Goddard Space Flight Center, 1998.

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F, Guinan E., Lu Wenxian, and United States. National Aeronautics and Space Administration., eds. A study of the chromospherically active, short-period binary VZ piscium. [Washington, DC: National Aeronautics and Space Administration, 1995.

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LEDESMA-ALBERT, Aida. Handbooks Engineering Science and Technology TIX. ECORFAN, 2021. http://dx.doi.org/10.35429/h.2021.9.1.1.128.

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Global warming and climate change coincide in their main causes, the massive emission of greenhouse gases, which retain heat in the atmosphere and on the earth's surface through the so-called greenhouse effect. The generation of electricity by means of fossil fuels is an important emitter of greenhouse gases (CO2, CH4, N2O), and halogenated compounds containing F, Cl, and Br. With the purpose of contributing to the construction of viable solutions to the current energy situation of the country and in the foundation of a sustainable future, the use of solar energy for the generation of electricity by means of solar panels represents an option. The purpose of this study is to describe and control the solar cell protection material Ethylene-Vinyl-Acetate (EVA), as a contribution to the Quality Assurance of solar panels, since the function of this material is essential for the protection of solar cells, which are a vital part of the solar panel. The tests performed were: Gel content, adhesion test, and durability tests. The results obtained were within specification according to IEC 61215. From this work it is concluded that it is important to continue testing the whole process and components of the solar panels in order to guarantee the useful life of the finished product, as well as to contribute to sustainable development.
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Book chapters on the topic "Line emission study"

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Bikam, Peter Bitta. "Technology Innovations in Green Transport." In Green Economy in the Transport Sector, 37–49. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-86178-0_4.

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AbstractThe paper uses the case study of Limpopo province to discuss technology innovations in green transport in South Africa with respect to the reduction of global greenhouse emission through technology innovation. South Africa’s emission from fuel combustion is the world’s 15th largest in forms of CO emission because it contributes about 1.2% of global emissions. In a submission from the Department of Environmental Affairs (DEA) on the impact of greenhouse emissions stated that companies are required to be innovative to reduce the carbon emission levels in South Africa. Literature on road transport in South Africa shows that road transport is the fastest growing source of greenhouse gas emissions, accounting for 19% of global energy consumption. The policy to promote an integrated public transport in municipalities is in line with the National Development Plan and the White Paper on National Climate Change Response. This requires innovative technology that promotes carbon trading markets such as taxi recapitalisation programmes and carbon tax on new vehicles. The study analysed the factors influencing green technology innovations in South Africa with specific reference to Limpopo province green transportation study. The methodology used to unpack innovative technology in South Africa discusses green technology in Limpopo province in the context of greenhouse gases emission reduction innovative technologies in the transport sector with respect to sustainable fuels, energy efficient systems and smart information as well as hybrid technologies. The study advances arguments on technologies for engine and propulsion systems, alternative energy sources, navigation technologies, cargo handling systems, heating and cooling vehicles, road and rail vehicles and maritime transportation with respect to innovations as well as battery charging systems, engine oil disposal etc. The findings shows that no single trajectory of technology innovation in green transport will suffice but technological innovations that improve fuel economy and transition from fossil fuels to cleaner fuel alternatives. The study in Limpopo province showed that green transport innovations must not obscure the role of non-technological innovations in reducing emissions, but the two should be tackled with green transport value chain as a whole.
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Gallego, J., J. Zamorano, M. Rego, A. G. Vitores, and O. Alonso. "Study of a Complete Sample of Hα Emission-Line Galaxies from the UCM Survey." In New Light on Galaxy Evolution, 380. Dordrecht: Springer Netherlands, 1996. http://dx.doi.org/10.1007/978-94-009-0229-9_92.

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Shimokawa, Tomotsugu. "Atomistic Study of Disclinations in Nanostructured Metals." In The Plaston Concept, 57–78. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-16-7715-1_3.

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AbstractDisclination is a line defect in which rotational symmetry is broken. Recently, such defects have been observed in nanostructured metals. Hence, disclinations can bring out the unique properties of nanostructured metals. This chapter shows two examples of disclination-mediated plastic phenomena observed in atomic simulations. The first one is the grain subdivision mechanism, which is related to the mobility of partial disclination under severe plastic deformation processes. The second one is a mechanism that improves the fracture toughness using the disclination shielding effect, which appears at grain boundaries after dislocation emission. These atomic simulations with the geometrical restrictions of boundary conditions showed the possibility of selecting a plastic deformation mode by designing structures, elements, and environments to obtain materials with excellent mechanical properties.
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Bochkarev, N. G., A. I. Shapovalova, and S. A. Zhekov. "A Study of Emission-line Variability of the Nucleus in the Seyfert Galaxy NGC 4151 in 1986–1989." In Physics of Active Galactic Nuclei, 189–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 1992. http://dx.doi.org/10.1007/978-3-642-77566-6_36.

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Huang, Zujian, and Wenyu Zhang. "Study on Carbon Emission of Laminated Bamboo Based on Life Cycle Assessment Method." In Lecture Notes in Civil Engineering, 84–96. Singapore: Springer Nature Singapore, 2022. http://dx.doi.org/10.1007/978-981-19-4293-8_10.

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Cucinotta, Filippo, Marcello Raffaele, and Fabio Salmeri. "A Well-to-Wheel Comparative Life Cycle Assessment Between Full Electric and Traditional Petrol Engines in the European Context." In Lecture Notes in Mechanical Engineering, 188–93. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-70566-4_30.

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AbstractAutomotive sector is crucial for the economic and social system. Conversely, it also plays an important role in the global emissions balance with strong consequences on the environment. Currently the Research world is engaged in the reduction of the emissions, especially in order to contrast the Climate Change and reduce toxicity on humans and the ecosystem. This study presents a comparative Life Cycle Assessment, Well-to-Wheel, between the most common technology used in the automotive sector, i.e. the traditional petrol Internal Combustion Engine and the full Battery Electric Vehicle. The different configurations have been analysed within 17 different impact categories in terms of climate change, human health, resourced depletion and ecosystems. The Well-to-Wheel approach allows to focus the attention on the use stage of the vehicle, considering the local effects due to the direct emissions in high density urban zones and it mitigates the dependence of usage hypotheses, different scenarios and intrinsic differences between the various models of cars in circulation.
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Liang, Zhiyi, Toru Matsumoto, Lei Zhang, and Bing Liu. "Study on the Quantitative Evaluation of Greenhouse Gas (GHG) Emissions in Sewage-Sludge Treatment System." In Sustainable Production, Life Cycle Engineering and Management, 271–87. Singapore: Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-6775-9_18.

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Durosinmi, M. A., J. O. Ojo, A. F. Oluwole, O. A. Akanle, and N. M. Spyrou. "Study of Trace Elements in Blood of Cancer Patients by Proton-Induced X-Ray Emission (PIXE) Analysis." In Nuclear Analytical Methods in the Life Sciences 1994, 351–55. Totowa, NJ: Humana Press, 1994. http://dx.doi.org/10.1007/978-1-4757-6025-5_42.

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Aktaş, Can B. "Importance of Building Energy Efficiency Towards National and Regional Energy Targets." In Towards a Sustainable Future - Life Cycle Management, 155–63. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-77127-0_14.

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AbstractThe buildings sector in the EU consumes 40% of energy and is responsible for 36% of CO2 emissions. With growing public interest on the subject, there have been several EU policies developed to curb impacts. Statistical analysis conducted in the case study indicates an increase in both total and buildings’ energy consumption trends leading up to 2030, with total energy consumption having an expected value of 40% increase and building energy consumption having an expected value of 33% increase. Analysis results indicate that building energy consumption could be maintained at current levels if a proactive approach is embraced. Focusing solely on buildings’ energy consumption does not solve national or regional energy problems, but neglecting them altogether prevents significant gains to be made. Building energy efficiency is not the solution by itself to achieve energy goals in EU, but is an important contributor toward the solution.
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Wei, Yimeng, Areti Markopoulou, Yuanshuang Zhu, Eduardo Chamorro Martin, and Nikol Kirova. "Additive Manufacture of Cellulose Based Bio-Material on Architectural Scale." In Proceedings of the 2021 DigitalFUTURES, 286–304. Singapore: Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-5983-6_27.

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AbstractThere are severe environmental and ecological issues once we evaluate the architecture industry with LCA (Life Cycle Assessment), such as emission of CO2 caused by necessary high temperature for producing cement and significant amounts of Construction Demolition Waste (CDW) in deteriorated and obsolete buildings. One of the ways to solve these problems is Bio-Material. CELLULOSE and CHITON is the 1st and 2nd abundant substance in nature (Duro-Royo, J.: Aguahoja_Programmable Water-based Biocomposites for Digital Design and Fabrication across Scales. MIT, pp. 1–3 (2019)), which means significantly potential for architectural dimension production. Meanwhile, renewability and biodegradability make it more conducive to the current problem of construction pollution. The purpose of this study is to explore Cellulose Based Biomaterial and bring it into architectural scale additive manufacture that engages with performance in the material development, with respect to time of solidification and control of shrinkage, as well as offering mechanical strength. At present, the experiments have proved the possibility of developing a cellulose-chitosan- based composite into 3D-Printing Construction Material (Sanandiya, N.D., Vijay, Y., Dimopoulou, M., Dritsas, S., Fernandez, J.G.: Large-scale additive manufacturing with bioinspired cellulosic materials. Sci. Rep. 8(1), 1–5 (2018)). Moreover, The research shows that the characteristics (Such as waterproof, bending, compression, tensile, transparency) of the composite can be enhanced by different additives (such as xanthan gum, paper fiber, flour), which means it can be customized into various architectural components based on Performance Directional Optimization. This solution has a positive effect on environmental impact reduction and is of great significance in putting the architectural construction industry into a more environment-friendly and smart state.
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Conference papers on the topic "Line emission study"

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Vasquez-Arnez, R. L., M. G. M. Jardini, M. Masuda, L. A. Carita, and J. A. Jardini. "Preventive inspection of line insulators through corona emission: A case study." In IEEE PES T&D 2010. IEEE, 2010. http://dx.doi.org/10.1109/tdc.2010.5484226.

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Limpouch, Jiri, A. B. Iskakov, Aleksandr A. Andreev, and Hidetoshi Nakano. "Simulation study of short-pulse laser energy conversion to x-ray line emission." In 26th European Conference on Laser Interaction with Matter (ECLIM 2000), edited by Milan Kalal, Karel Rohlena, and Milan Sinor. SPIE, 2001. http://dx.doi.org/10.1117/12.425554.

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Guo, Yunan, and Xiaojian Hao. "Experimental study of static calibration based on atomic- emission double spectrum line temperature measuring." In CIOP100, edited by Yue Yang. SPIE, 2018. http://dx.doi.org/10.1117/12.2506255.

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Furuta, Katsunori, Shinobu Sasaki, and Michihiro Tokuda. "Study of the In-Line Pump System for Diesel Engines to Meet Future Emission Regulations." In International Congress & Exposition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1998. http://dx.doi.org/10.4271/980812.

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Schmidt, M., S. Gorny, N. Rüssmeier, and K. Partes. "Investigation on Laser Cladding Processes Using High-Resolution In-Line Atomic Emission Spectroscopy." In ITSC2022. DVS Media GmbH, 2022. http://dx.doi.org/10.31399/asm.cp.itsc2022p0876.

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Abstract Process monitoring and control methods during direct metal deposition (DMD) are used to ensure a consistent manufacturing quality of the process. In the optical regime, naturally occurring process emission provides therefore selective and specific element lines, which can be obtained by optical spectrometers. However, DMD processes are in the heat conduction regime and superimposed broad spectral emissions dominate the wavelength specific signals. The aim of this work is to investigate the occurrence of different elemental lines in DMD processes as well as deposition track cross-sectional dimensions. Therefore, experiments were simultaneously conducted by using a high-resolution spectrometer (resolution = approx. 47 pm FWHM at 522 nm and 55 pm FWHM at 407.5 nm) and a medium resolution spectrometer (resolution = 0.73 nm FWHM), which were coupled by a bifurcated optical fibre. A parameter study of 27 single track DMD experiments using Co-Cr-based (MetcoClad21) powder on low-alloyed tool steel C45W (1.1730) substrate material, varying laser power, scan velocity and powder feed rate was conducted. Series of spectra were obtained for all sets of parameters with a scan rate of 100 Hz. The individual wavelength spectrum was analysed and classified by an algorithm into two types. Type-A spectra, with specific element emission lines and Type-B spectra, without significant emission lines with mostly predominant thermal emission radiation. Each deposition track was coupled to cross-sectional dimensions, including height, welding depth and melted areas. In addition, certain elemental lines contained in Type-A spectra were verified by using data from the NIST atomic spectra database. The investigation indicates that the relative number of Type-A spectra with respect to the total quantity of spectra, correlates significant to the process parameters. All detected and identified element lines occurred to be non-ionised elements, especially Cr I, Fe I and Mn I lines were frequently observed.
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Koryukina, E. V. "A theoretical study of line intensities in emission spectra of rare gas atoms in an alternating electric field." In 2017 Progress In Electromagnetics Research Symposium - Spring (PIERS). IEEE, 2017. http://dx.doi.org/10.1109/piers.2017.8262305.

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Gao, G., L. Pershin, and J. Mostaghimi. "Optical Emission Spectroscopic Diagnostics of Atmospheric Argon Radio Frequency Inductively Coupled Plasma." In ITSC2003, edited by Basil R. Marple and Christian Moreau. ASM International, 2003. http://dx.doi.org/10.31399/asm.cp.itsc2003p1337.

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Abstract An experimental study is conducted to determine the property fields of 40 MHz argon radio frequency inductively coupled plasma using optical emission spectroscopy. The pure argon plasma was operated at the input power of 0.3 kW and under atmospheric pressure. 29 atomic argon lines with upper level energies ranging from 12.9 to 15.5 eV, continuum emission and line width are used to evaluate plasma parameters such as temperature and electron number density. Since 40 MHz plasma is in almost complete nonequilibrium, the validaty and accuracy of most usual spectroscopic methods are questioned. Analysis based on the Boltzmann diagram, line-to-continuum intensity ratio, population of continuum extrapolated level, and continuum intensity reveals the departure from thermodynamic equilibrium in the plasma. Among these methods, the Boltzmann diagram method is shown to provide reliable plasma excitation temperature as long as the Boltzmann plot is drawn based on enough spectra lines covering from infrared to ultraviolet regions. The continuum emission at wavelengths within visible region can give good estimation of the electron density by using excitation temperature in the continuum relation. The line-to-continuum is not a reliable method for the temperature measurement of nonequilibrim plasma. The electron density obtained from the Saha plot can provide rough estimation of the electron density. It is shown that the electron-atom interaction contribution to the continuum radiation is more important than being expected before for the argon plasma in our study. The non-axisymmetric distribution of the emission was found to exist within the coil zone of the plasma, which may affect the estimation of the local emission coefficient, and consequently the measured plasma fields.
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Menneveux, Jérôme, and Jocelyn Veilleux. "An Optical Emission Spectroscopy Study of Plasma-Precursor Interactions in Solution Precursor Plasma Spray." In ITSC2018, edited by F. Azarmi, K. Balani, H. Li, T. Eden, K. Shinoda, T. Hussain, F. L. Toma, Y. C. Lau, and J. Veilleux. ASM International, 2018. http://dx.doi.org/10.31399/asm.cp.itsc2018p0294.

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Abstract In this work, optical emission spectroscopy is used to study plasma-liquid precursor interactions in a plasma spray process. A mapping of the plasma jet is performed with a bundle of seven optical fibers while injecting various liquid precursors. Two suspensions containing a titania (TiO2) powder in different solvents and one solution containing titanium butoxide are analyzed. For each precursor, the evolution of both temperature and spectral line intensities along the plasma jet are observed. Comparing these results brings a new understanding of the precursor decomposition inside the plasma, while the noted contrasts between water and ethanol as solvent, and between the use of a powder and that of an alkoxide as a source of titanium, help to assess the effect of these parameters on the plasma spray process.
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Hargude, N. V., and S. M. Sawant. "Experimental Investigation of a Spark Ignited Engine Using Magnetic Air Conditioner (MAC) for Improved Performance and Reduced Emissions." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-66521.

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In 21st century, to cope up with exponential technological development, use of eco-friendly conventional energy system is a critical issue. Saving of energy is nothing but production of energy. Conventional fuel used in stationary power plant an IC engine is bulk in quantity, which will not be last longer and will exhaust very soon. Stationary power plants and Automobile propelled by I.C. engines have a problem of pollutant emission in environment which mainly depends on combustion process occurs in power plant and I.C. engines. Incomplete combustion of hydro-carbon fuel/s produce very large amount of harmful emission gases resulting into smog in cities & reduces performance of the system. These systems, equipped with Internal Combustion or External combustion produces large amount of exhaust gases CO, HC and NOx like monoxides etc. Since hazardous emissions which are harmful to human life and ecosystem resulting in many types of diseases of human especially in urban areas where automobile vehicle equipped with IC engine density is very high. These emissions have effect on result in environmental cycles also. In today’s globalised world, many attempts are made to reduce intensity of hazardous emissions of an IC engine through pre processing of fuels and post processing combustion exhaust gases in IC engine by many means like MPFI, PCV, EGR, catalytic converter, supercharger, turbocharger, etc. In order to handle, these issues, additional attempt is made. This attempt uses Air conditioner/Energizer for Pre-processing air and unit developed called as Magnetic air Conditioner (MAC). A permanent magnet, magnetic air conditioner (MAC) is mounted in path of air lines. Mounting MAC in air line enhances quality of air and air molecules properties like it aligns and orientations, especially in an oxygen molecule. Better atomization of an oxygen molecule which further enters into combustion chambers of SI engine along with air. In a conventional four stroke spark Ignited engine, oxygen molecules reacts with hydro -carbon, which assist for complete combustion of hydro-carbon. Use of such Magnetic air conditioners improves performance of SI engine. The specific fuel consumption also decreases, resulting in to decrease in BSFC with increase in load. Use of MAC in engine also reduces emissions like CO, HC, ultimately resulting into reduction in smog in urban areas. The present article describes the mechanism of MAC, objectives and its effect on SI engine, such as enhanced performance parameter, various efficiencies like mechanical, brake thermal, volumetric saving in fuel, and reduced emission. One case study is presented in which ferrite magnets are used as MAC which improves performance and reduces emissions.
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Hossainpour, Siamak, and Bahman Haddadi. "Numerical Study of the Effects of Volumetric Heat Transfer and Emissivity Coefficient and Porosity on Combustion and Pollutants Formation in a Porous Burner." In ASME 2008 International Mechanical Engineering Congress and Exposition. ASMEDC, 2008. http://dx.doi.org/10.1115/imece2008-68565.

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In recent years, more attention has been focused on the use of porous materials to enhance the efficiency of combustion systems and to reduce the emission of pollutants. This is because combustion in inert porous media offers an interesting and promising route towards burner with high-power density, high-power dynamic range, and very low emission of pollutants such as NOx and CO. This work reports one-dimensional combustion in a porous burner using three combustion models: GRI 3.0, GRI 2.11, skeletal mechanism. We conclude that GRI 2.11 mechanism has a good agreement with GRI 3.0 and it costs less. At first, we present a numerical study which shows the effects of these models on temperature, species and pollutant emissions. Then, we investigate the effects of volumetric heat transfer and emissivity coefficient and porosity on combustion and pollutions. It was concluded that NO and CO emission depend mainly on the volumetric and emissivity coefficient. When volumetric heat transfer increased, the difference between gas and solid temperature reduced, therewith NO formation noticeably decreased whereas CO emission didn’t change sensible. On the other hand, the flame peak temperature is increased with the reduction of the solid emissivity coefficient. This important conclusion means that NO and CO emission and velocity increases. Also gas and solid temperature increase and vice versa. The other parameter is Porosity. Increasing in porosity of burner resulted in decreasing gas and solid temperature and subsequently NO and CO emission decreased sensible. Porosity has effected on velocity, too. As porosity decreased, velocity increased. Emissivity effects on the rate of heat flux which issue from burner. As the emissivity increased the efficiency of burner arose. Also these parameters have important roles in decreasing the emission especially on No emission because it has more depend on temperature. In addition the resulted gas and solid temperatures were compared with reported measurements of center line temperature in a cylindrical porous burner. The good agreement with experimental observation upholds that the numerical model is a perfect tool to investigate combustion and pollutants formation in porous media.
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Reports on the topic "Line emission study"

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Vreeland, Heidi, Christina Norris, Lauren Shum, Jaya Pokuri, Emily Shannon, Anmol Raina, Ayushman Tripathi, et al. Collaborative Efforts to Investigate Emissions From Residential and Municipal Trash Burning in India. RTI Press, September 2018. http://dx.doi.org/10.3768/rtipress.2018.rb.0019.1809.

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Emissions from trash burning represent an important component of regional air quality, especially in countries such as India where the practice of roadside, residential, and municipal trash burning is highly prevalent. However, research on trash emissions is limited due to difficulties associated with measuring a source that varies widely in composition and burning characteristics. To investigate trash burning in India, a collaborative program was formed among RTI, Duke University, and the India Institute of Technology (IIT) in Gandhinagar, involving both senior researchers and students. In addition to researching emission measurement techniques, this program aimed to foster international partnerships and provide students with a hands-on educational experience, culminating in a pilot study in India. Before traveling, students from Duke and IIT met virtually to design experiments. IIT students were able to visit proposed sites and offer specified knowledge on burning practices prior to the pilot study, allowing potential experiments to be iteratively improved. The results demonstrated a proof of concept of using a low-cost sensor attached to a commercial drone to measure emissions from a municipal dump site. In addition, for small-scale residential and roadside trash burning, a combustor was designed to burn trash in a consistent way. Results suggested that thermocouples and low-cost sensors may offer an affordable way for combustor designers to assess particulate emissions during prototype iterations. More experiences like this should be made available so that future research can benefit from the unique insights that come from having veteran researchers work with students and from forming international partnerships.
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Skone, Timothy J., and William E. Harrison, III. Case Study: Interagency Workgroup on Life Cycle GHG Emissions of Alternative Aviation Fuels. Office of Scientific and Technical Information (OSTI), September 2011. http://dx.doi.org/10.2172/1523644.

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Al-Qadi, Imad, Jaime Hernandez, Angeli Jayme, Mojtaba Ziyadi, Erman Gungor, Seunggu Kang, John Harvey, et al. The Impact of Wide-Base Tires on Pavement—A National Study. Illinois Center for Transportation, October 2021. http://dx.doi.org/10.36501/0197-9191/21-035.

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Researchers have been studying wide-base tires for over two decades, but no evidence has been provided regarding the net benefit of this tire technology. In this study, a comprehensive approach is used to compare new-generation wide-base tires (NG-WBT) with the dual-tire assembly (DTA). Numerical modeling, prediction methods, experimental measurements, and environmental impact assessment were combined to provide recommendations about the use of NG-WBT. A finite element approach, considering variables usually omitted in the conventional analysis of flexible pavement was utilized for modeling. Five hundred seventy-six cases combining layer thickness, material properties, tire load, tire inflation pressure, and pavement type (thick and thin) were analyzed to obtained critical pavement responses. A prediction tool, known as ICT-Wide, was developed based on artificial neural networks to obtain critical pavement responses in cases outside the finite element analysis matrix. The environmental impacts were determined using life cycle assessment. Based on the bottom-up fatigue cracking, permanent deformation, and international roughness index, the life cycle energy consumption, cost, and green-house gas (GHG) emissions were estimated. To make the outcome of this research effort useful for state departments of transportation and practitioners, a modification to AASHTOWare is proposed to account for NG-WBT. The revision is based on two adjustment factors, one accounting for the discrepancy between the AASHTOware approach and the finite element model of this study, and the other addressing the impact of NG-WBT.
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Al-Qadi, Imad, Hasan Ozer, Mouna Krami Senhaji, Qingwen Zhou, Rebekah Yang, Seunggu Kang, Marshall Thompson, et al. A Life-Cycle Methodology for Energy Use by In-Place Pavement Recycling Techniques. Illinois Center for Transportation, October 2020. http://dx.doi.org/10.36501/0197-9191/20-018.

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Worldwide interest in using recycled materials in flexible pavements as an alternative to virgin materials has increased significantly over the past few decades. Therefore, recycling has been utilized in pavement maintenance and rehabilitation activities. Three types of in-place recycling technologies have been introduced since the late 70s: hot in-place recycling, cold in-place recycling, and full-depth reclamation. The main objectives of this project are to develop a framework and a life-cycle assessment (LCA) methodology to evaluate maintenance and rehabilitation treatments, specifically in-place recycling and conventional paving methods, and develop a LCA tool utilizing Visual Basic for Applications (VBA) to help local and state highway agencies evaluate environmental benefits and tradeoffs of in-place recycling techniques as compared to conventional rehabilitation methods at each life-cycle stage from the material extraction to the end of life. The ultimate outcome of this study is the development of a framework and a user-friendly LCA tool that assesses the environmental impact of a wide range of pavement treatments, including in-place recycling, conventional methods, and surface treatments. The developed tool provides pavement industry practitioners, consultants, and agencies the opportunity to complement their projects’ economic and social assessment with the environmental impacts quantification. In addition, the tool presents the main factors that impact produced emissions and energy consumed at every stage of the pavement life cycle due to treatments. The tool provides detailed information such as fuel usage analysis of in-place recycling based on field data.
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Lu, Tianjun, Jian-yu Ke, Fynnwin Prager, and Jose N. Martinez. “TELE-commuting” During the COVID-19 Pandemic and Beyond: Unveiling State-wide Patterns and Trends of Telecommuting in Relation to Transportation, Employment, Land Use, and Emissions in Calif. Mineta Transportation Institute, August 2022. http://dx.doi.org/10.31979/mti.2022.2147.

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Telecommuting, the practice of working remotely at home, increased significantly (25% to 35%) early in the COVID-19 pandemic. This shift represented a major societal change that reshaped the family, work, and social lives of many Californians. These changes also raise important questions about what factors influenced telecommuting before, during, and after COVID-19, and to what extent changes in telecommuting have influenced transportation patterns across commute modes, employment, land use, and environment. The research team conducted state-level telecommuting surveys using a crowd-sourced platform (i.e., Amazon Mechanical Turk) to obtain valid samples across California (n=1,985) and conducted state-level interviews among stakeholders (n=28) across ten major industries in California. The study leveraged secondary datasets and developed regression and time-series models. Our surveys found that, compared to pre-pandemic levels, more people had a dedicated workspace at home and had received adequate training and support for telecommuting, became more flexible to choose their own schedules, and had improved their working performance—but felt isolated and found it difficult to separate home and work life. Our interviews suggested that telecommuting policies were not commonly designed and implemented until COVID-19. Additionally, regression analyses showed that telecommuting practices have been influenced by COVID-19 related policies, public risk perception, home prices, broadband rates, and government employment. This study reveals advantages and disadvantages of telecommuting and unveils the complex relationships among the COVID-19 outbreak, transportation systems, employment, land use, and emissions as well as public risk perception and economic factors. The study informs statewide and regional policies to adapt to the new patterns of telecommuting.
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Keller, David P. Quantification of “constrained” potential of ocean NETs. OceanNets, 2022. http://dx.doi.org/10.3289/oceannets_d4.1.

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This study uses an existing perturbed parameter ensemble (PPE) of simulated ocean CO2 removal (CDR) to better determine sustainable pathways of ocean-based NET deployment and to provide information to constrain the design of subsequent modelling experiments. The results show that ocean alkalinity enhancement (OAE) can only help meet SDG13 (Climate Action) when other ambitious mitigation efforts are taken. This reinforces that OAE is not a substitute for emissions reduction, but could contribute to meeting our climate goals (if other factors suggest OAE is worth doing). For SDG14 (Life Below Water), the results suggest OEA can contribute to limiting or even reversing ocean acidification. Meeting many other SDG14 objectives is closely linked to also meeting SDG13. A key recommendation is therefore, that subsequent simulations in OceanNETs should only use SDG13 compatible baseline scenarios, unless there is some specific need for process understanding at higher levels of climate change. The analysis has also determined that the idealized CDR in the PPE is not suitable for determining many socio-economic constraints and the implications that these have for meeting the SDGs. Another key recommendation is therefore, that subsequent simulations within OceanNETs should use more realistic scenarios of CDR deployment.
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Mazari, Mehran, Siavash F. Aval, Siddharth M. Satani, David Corona, and Joshua Garrido. Developing Guidelines for Assessing the Effectiveness of Intelligent Compaction Technology. Mineta Transportation Institute, January 2021. http://dx.doi.org/10.31979/mti.2021.1923.

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Many factors affect pavement compaction quality, which can vary. Such variability may result in an additional number of passes required, extended working hours, higher energy consumption, and negative environmental impacts. The use of Intelligent Compaction (IC) technology during construction can improve the quality and longevity of pavement structures while reducing risk for contractors and project owners alike. This study develops guidelines for the implementation of IC in the compaction of pavement layers as well as performing a preliminary life-cycle cost analysis (LCCA) of IC technology compared to the conventional compaction approach. The environmental impacts of the improved construction process were quantified based on limited data available from the case studies. The LCCA performed in this study consisted of different scenarios in which the number of operating hours was evaluated to estimate the cost efficiency of the intelligent compaction technique during construction. The analyses showed a reduction in energy consumption and the production of greenhouse gas (GHG) emissions with the use of intelligent compaction. The LCCA showed that the use of IC technology may reduce the construction and maintenance costs in addition to enhancing the quality control and quality assurance (QC/QA) process. However, a more comprehensive analysis is required to fully quantify the benefits and establish more accurate performance indicators. A draft version of the preliminary guidelines for implementation of IC technology and long-term monitoring of the performance of pavement layers compacted thereby is also included in this report.
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