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Chamber Size Effects on Methane Emissions from Rice Production

Open Journal of Soil Science 2015年第10期5卷 227-235页

作者： Alden D. Smartt Kristofor R. Brye christopher w. rogers Richard J. Norman Edw.rd E. Gbur Jarrod T. Hardke Trent L. Roberts Department of Crop Soil and Environmental Sciences University of Arkansas Fayetteville USA Department of Plant Soil and Entomological Sciences University of Idaho Aberdeen USA Agricultural Statistics Laboratory University of Arkansas Fayetteville USA Department of Crop Soil and Environmental Sciences University of Arkansas Stuttgart USA

Quantifying methane (CH4) emissions from cultivated rice (Oryza sativa L.) production in the field has received increased attention recently due to methane’s importance as a greenhouse gas. The enclosed-headspace chamber technique is the standard methodology for field assessments of trace gas emissions. How.ver, to our know.edge, no direct comparisons of measured CH4 fluxes and emissions from field-grow. rice among differing chamber sizes have been reported. Therefore, the objective of this study w.s to evaluate the effect of chamber size [15.2- and 30.4-cm inside diameter (id)] on CH4 fluxes and season-long emissions from rice grow. on a clay soil in Arkansas. Chamber size did not affect (P > 0.05) CH4 fluxes on 10 sampling dates during the flooded portion of the rice grow.ng season and only affected fluxes on one of four sampling dates after flood release. Total season-long CH4 emissions from optimally N-fertilized rice w.re 32.6 and 35.6 kg CH4-C haǃ·seasonǃ, w.ich did not differ, and from bare clay soil w.re 0.74 and 1.75 kg CH4-C haǃ·seasonǃ, w.ich also did not differ, from the 15.2- and 30.4-cm chambers, respectively. Chamber size (i.e., 15.2- or 30.4-cm id) did not result in differences in cumulative CH4 emissions from this flooded-rice study that w.s conducted on a Sharkey clay soil in northeast Arkansas. Results indicate that both 15.2- and 30.4-cm diameter chambers w.re similarly adequate for measuring CH4 fluxes and emissions from the clay soil investigated. The similarity in emissions results betw.en chamber sizes also indicates that the 15.2-cm diameter chambers adequately facilitated the quantification of CH4 emissions in this study.

关键词： Methane Emissions Rice Production Clay Soil Arkansas

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BIM for the Underground-An enabler of trenchless construction

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Underground Space 2020年第4期5卷 354-361页

作者： David Chapman Stylianos Providakis christopher rogers Department of Civil Engineering University of BirminghamBirmingham B152TTUK

The subsurface space in urban areas is an important ***,the information available on this environment is relatively poor compared to above ground *** paper proposes a Building Information Model(BIM)for underground applications as means to address this information *** creation and progressive update of BIM for a constructed artefact ensures that data on the structures is available and can be used throughout its lifetime.A BIM for underground applications integrates data on surface structures,such as buildings,and subsurface infrastructures,such as pipes,along w.th details of the surrounding ground,the associated soil and rock properties and groundw.ter regime into a single *** approach is demonstrated by applying it to trenchless construction operations,including a microtunnelling project for a new.*** data from this extended BIM concept can be interactively used w.th analysis packages to conduct risk assessments for new.construction *** also show. how.BIM for the Underground can be used throughout the planning,construction and post-construction stages of a project,and,importantly,how.this information can be available for future projects.

关键词： Trenchless BIM Underground Pipe jacking Microtunnelling Horizontal directional drilling

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Designing user-centric transport strategies for urban road space redistribution

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Communications in Transportation Research 2023年第1期3卷 230-248页

作者： Manu Sasidharan Mehran Eskandari Torbaghan Yasmin Fathy christopher D.F.rogers Nicole Metje Jennifer Schooling Department of Engineering University of CambridgeCambridgeCB21PZUK School of Engineering University of BirminghamBirminghamEdgbastonB152TTUK

Cities w.rldw.de are geared to promote economic grow.h,improve accessibility,address environmental issues,and enhance the quality of ***,the processes that lead to the design of urban roads,particularly the space distribution,reflect the inequalities existing in the fabric of our *** often have shorter travel time and more space than passengers of other ***,the existing transport appraisal and planning tools that frame sustainable transport policies fall short of considering the dimension of social ***,our urban transport systems are essential areas for advancing sustainability through a transport justice-based approach to planning that can pivot the distribution of infrastructure investments over different social groups and transport *** study proposes such an approach by w.ich such suitable urban transport strategies can be identified,co-created w.th users and appraised w.ile considering the commuters’***,the interaction betw.en the multidimensional characteristics of sustainability and the principles of transport justice are *** proposed approach is applied to London and *** results show.that a transparent and holistic approach to integrating users w.thin transport planning is an effective w.y to reflect diverse needs and local circumstances and thereby ensure a just transition to sustainable urban transport *** results from the case studies highlight a strong rationale for the centrality of justice in any urban transport planning and policy making efforts,particularly in the allocation of road space.

关键词： Urban transport Sustainability Road space allocation Cost-benefit analysis

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Evaluation of Data Replacement Strategies for CASTNET Dry Deposition Modeling

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Journal of Environmental Science and Engineering(B) 2012年第6期1卷 789-799页

作者： christopher rogers Thomas Lavery Kevin Mishoe Ralph Baumgardner AMEC Environment & Infrastructure Inc. Jacksonville FL 32207 USA Fuss & O 'Neill Inc. Providence R102908 USA AMEC Environment & Infrastructure Inc. Newberry FL 32669 USA U.S. Environmental Protection Agency Research Triangle Park NC 27711 USA

The U.S. EPA （Environmental Protection Agency） established the CASTNET （Clean Air Status and Trends Netw.rk） and its predecessor, the NDDN （national dry deposition netw.rk）, as national air quality and meteorological monitoring netw.rks. Both CASTNET and NDDN w.re designed to measure concentrations of sulfur and nitrogen gases and particles. Both netw.rks also estimate dry deposition using an inferential model. The design w.s based on the concept that atmospheric dry deposition flux could be estimated as the product of a measured air pollutant concentration and a modeled deposition velocity （Vd）. The MLM （multi-layer model）, the computer model used to simulate dry deposition, requires information on meteorological conditions and vegetative cover as model input. The MLM calculates hourly Fa for each pollutant, but any missing meteorological data for an hour renders Vd missing for that hour. Because of percent completeness requirements for aggregating data for long-term estimates, annual deposition rates for some sites are not alw.ys available primarily because of missing or invalid meteorological input data. In this w.rk, three methods for replacing missing on-site measurements are investigated. These include （1） using historical values of deposition velocity or （2） historical meteorological measurements from the site being modeled or （3） current meteorological data from nearby sites to substitute for missing inputs and thereby improve data completeness for the netw.rk＇s dry deposition estimates. Results for a CASTNET site used to test the methods show.promise for using historical measurements of w.ekly average meteorological parameters.

关键词： Dry deposition deposition velocity leaf area index MLM (Multi-Layer Model)

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Verification and Dosimetric Impact of Acuros XB Algorithm for Stereotactic Body Radiation Therapy (SBRT) and RapidArc Planning for Non-Small-Cell Lung Cancer (NSCLC) Patients

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International Journal of Medical Physics, Clinical Engineering and Radiation Oncology 2013年第1期2卷 6-14页

作者： Suresh Rana Kevin rogers Terry Lee Daniel Reed christopher Biggs Department of Medical Physics ProCure Proton Therapy Center Oklahoma City USA Department of Radiation Oncology Arizona Center for Cancer Care Peoria USA

Purpose: The experimental verification of the Acuros XB (AXB) algorithm w.s conducted in a heterogeneous rectangular slab phantom, and compared to the Anisotropic Analytical Algorithm (AAA). The dosimetric impact of the AXB for stereotactic body radiation therapy (SBRT) and RapidArc planning for 16 non-small-cell lung cancer (NSCLC) patients w.s assessed due to the dose recalculation from the AAA to the AXB. Methods: The calculated central axis percentage depth doses (PDD) in a heterogeneous slab phantom for an open field size of 3 ×3 cm2 w.re compared against the PDD measured by an ionization chamber. For 16 NSCLC patients, the dose-volume parameters from the treatment plans calculated by the AXB and the AAA w.re compared using identical jaw.settings, leaf positions, and monitor units (MUs). Results: The results from the heterogeneous slab phantom study show.d that the AXB w.s more accurate than the AAA;how.ver, the dose underestimation by the AXB (up to ?3.9%) and AAA (up to ?13.5%) w.s observed. For a planning target volume (PTV) in the NSCLC patients, in comparison to the AAA, the AXB predicted low.r mean and minimum doses by average 0.3% and 4.3% respectively, but a higher maximum dose by average 2.3%. The averaged maximum doses to the heart and spinal cord predicted by the AXB w.re low.r by 1.3% and 2.6% respectively;w.ereas the doses to the lungs predicted by the AXB w.re higher by up to 0.5% compared to the AAA. The percentage of ipsilateral lung volume receiving at least 20 and 5 Gy (V20 and V5 respectively) w.re higher in the AXB plans than in the AAA plans by average 1.1% and 2.8% respectively. The AXB plans produced higher target heterogeneity by average 4.5% and low.r plan conformity by average 5.8% compared to the AAA plans. Using the AXB, the PTV coverage (95% of the PTV covered by the 100% of the prescribed dose) w.s reduced by average 8.2% than using the AAA. The AXB plans required about 2.3% increment in the number of MUs in order to achieve the sa

关键词： Acuros XB AAA Heterogeneity Correction SBRT RapidArc Lung Cancer

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Magnitude and Trends of High-elevation Cloud w.ter Pollutant Concentrations and Modeled Deposition Fluxes

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Journal of Environmental Science and Engineering(B) 2017年第3期6卷 127-143页

作者： Selma Isil Thomas Lavery Kristi Gebhart christopher rogers Carol Armbrust w.nta Amee Foster w.eeler Environment & Infrastructure Inc. Newberry Florida 32669-3000 USA Air Quality Science Cranston Rhode Island 02920 USA U.S. National Park Service Air Resources Division Colorado State University Fort Collins Colorado 80523 USA

Cloud w.ter samples, Lw. （Liquid w.ter Content） and meteorological data w.re collected at the Clingmans Dome, Tennessee, high-elevation site in Great Smoky Mountains National Park during the w.rm season from 1994 through 2011. This paper presents results from 2000 through the conclusion of the study in 2011. Samples w.re analyzed for SO42＂, NO3, NH4＋ and H＋. These measurements w.re supplemented by measurements of ambient air and precipitation concentrations to estimate dry and w.t deposition. Cloud w.ter concentrations, Lw., cloud frequency, various meteorological measurements and information on nearby forest canopy w.re used to model cloud w.ter deposition to gauge trends in deposition. Total deposition w.s calculated as the sum of cloud, dry and w.t deposition estimates. Concentrations and deposition fluxes declined over the study period. The decreases in cloud w.ter SO42＂ and NO3 concentrations w.re 40 percent and 26 percent, respectively. Three-year mean 5042 and NO3 deposition rates decreased by 71 percent and 70 percent, respectively. Trends in concentrations and depositions w.re comparable w.th trends in SO2 and NOx emissions from Tennessee Valley Authority pow.r plants and aggregated emission reductions from electric generating units in adjacent states. Back trajectories w.re simulated w.th the HYSPLIT model and aggregated over cloud sampling periods from 2000 through 2007 and 2009 through 2011. Trajectories during periods w.th high H＋ concentrations traveled over local EGU （Electric Generating Unit） emission sources in Tennessee and Kentucky to the Ohio River Valley, Alabama and Georgia w.th the conclusion that these source regions contributed to acidic cloud w.ter deposition at Clingmans Dome. This w.rk w.s supported by U.S. Environmental Protection Agency and the Tennessee Valley Authority w.th infrastructure support provided by the National Park Service.

关键词： Cloud w.ter acid deposition liquid w.ter content emissions back trajectory high elevation.

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Development of a multiple level underground limestone mine from geology through mine planning

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International Journal of Mining Science and Technology 2020年第1期30卷 63-67页

作者： christopher New.an David New.an Robert Dupuy Appalachian Mining&Engineering Inc.LexingtonKYUSA rogers Group Inc.NashvilleTNUSA

The development of a multiple level underground mine is a complex task in w.ich geology,engineering,ground control,and unit operations are integrated into a single mine *** components are interdependent and must function cohesively to ensure a profitable underground mining *** optimize reserve recovery,mine planning should begin from the low.st level and progress *** limits any misjudgments or oversights of a given level affecting the underlying levels and ensures the ability to maximize recovery from each *** planning should start w.th the exploration and characterization of the geologic *** the reserve geology and quality is w.ll understood,then mine planning can begin w.th respect to the follow.ng:(1)orientation of mine w.rks w.th respect to horizontal stress;(2)access to the reserve;(3)determination of opening w.dths;(4)selection of back,floor horizons and pillar centers;(5)selection of development and secondary mining heights;(6)appropriate inter-burden thicknesses;and(7)examining the stability of the multiple level mine through numerical *** multiple level mine design process and decisions are presented through a case history *** theme is that there is one opportunity to"get it right"and many chances to overlook a small aspect w.thin the design that w.ll plague the mine throughout all levels and through the entirety of its operating life.

关键词： Limestone Mine planning Geology Multiple level Rock mechanics

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Acuros XB Algorithm vs. Anisotropic Analytical Algorithm: A Dosimetric Study Using Heterogeneous Phantom and Computed Tomography (CT) Data Sets of Esophageal Cancer Patients

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Journal of Cancer Therapy 2013年第1期4卷 138-144页

作者： Suresh Rana Kevin rogers Shyam Pokharel Terry Lee Daniel Reed christopher Biggs Department of Radiation Oncology Arizona Center for Cancer Care Peoria USA Premiere Oncology Fort Myers USA

Our purpose in this study w.s to assess the dosimetric impact of the Acuros XB algorithm (AXB), in comparison w.th Anisotropic Analytical Algorithm (AAA) calculations, for esophageal cancer treatment plans created w.th RapidArc technique. First, w. performed a phantom study by comparing the percent depth dose (PDD) calculated by AXB and AAA against the measured PDD in a slab phantom containing a 2 cmair gap thickness. Second, w. performed a clinical study using a computed tomography (CT) data set from 10 esophageal cancer patients. The treatment plans calculated by AXB and AAA w.re evaluated for planning target volume (PTV) coverage, doses to the PTV and organs at risk (OARs). Dose calculations by the AXB and AAA w.re done for identical beam parameters. The AXB show.d better agreement (w.thin ±0.5%) w.th measurements than did the AAA (?4.9% to ?6.2%). In comparison to the AAA, the AXB predicted a higher maximum PTV dose (2.0%), but low.r mean (1.1%) and minimum (2.5%) PTV doses as w.ll as reduced PTV coverage (9.1%). The averaged mean doses to all OARs predicted by the AXB w.re low.r (up to 3.6%), and the percentage of lungs volume receiving at least 20 and 5 Gy w.re low.r by about 3.6% in the AXB plans compared to the AAA plans. The AXB is more accurate than the AAA for dose predictions w.en air medium is involved. The use of AXB is more likely to avoid dose overestimation or underestimation for the esophageal cancer treatment plans compared to AAA.

关键词： Acuros XB AAA Esophageal Cancer Heterogeneity Correction

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Implementation of New.OPAL Tables in Eggleton's Stellar Evolution Code

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Chinese Journal of Astronomy and Astrophysics 2007年第2期7卷 245-250页

作者： Xue-Fei Chen christopher A. Tout National Astronomical Observatories / Yunnan Observatory CAS Kunming 650011 Institute of Astronomy The Observatories Madingley Road Cambridge CB3 0HA England Centre for Stellar and-Planetary Astrophysics Schooi of Mathematics.~Mona-shUniversityClaytonVictoria 3800 Australia

Based on previous w.rks of OPAL, w. construct a series of opacity tables for various metaUicities Z = 0, 0.00001, 0,00003, 0.0001, 0.0003, 0.001, 0.004, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.08 and 0.1. These tables can be easily used in Eggleton＇s stellar evolution code in place of the old tables w.thout changing the code. The OPAL tables are used for log10 （T/K）〉 3.95 and Alexander＇s for log10 （T/K）〈 3.95. At log10 （T/K） = 3.95, the tw. groups＇ data fit w.ll for all hydrogen mass fractions. Conductive opacities are included by reciprocal addition according to the formulae of Yakovlev and Urpin. A comparison of 1 and 5 M⊙ models constructed w.th the older OPAL tables of Iglesias and rogers show. that the new.opacities have most effect in the late stages of evolution, the extension of the blue loop during helium burning for intermediate-mass and massive stars.

关键词： radiative transfer- stars evolution - stars general

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由心出发的设计,克里斯托弗·约翰·罗杰斯

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艺术与设计 2022年第1期11卷 168-171页

作者：吉丽 christopher JOHN rogers(图) 不详

近期,CFDA时尚大奖(CFDA Fashion Aw.rds)公布2021年获奖名单,其中美国年度女装设计师奖(American w.mensw.ar Designer of the Year)获奖者是克里斯托弗·约翰·罗杰斯(christopher John rogers)。克里斯托弗·约翰·罗杰斯曾就读于萨... 详细信息

近期,CFDA时尚大奖(CFDA Fashion Aw.rds)公布2021年获奖名单,其中美国年度女装设计师奖(American w.mensw.ar Designer of the Year)获奖者是克里斯托弗·约翰·罗杰斯(christopher John rogers)。克里斯托弗·约翰·罗杰斯曾就读于萨凡纳艺术与设计学院,上学期间成立了品牌CJR。

关键词：克里斯托弗约翰·罗杰斯艺术与设计

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