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Evaluating the Effect of Tillage on Carbon Sequestration Using the minimum detectable difference Concept

Pedosphere 2008年第4期18卷 421-430页

作者： X. m. YANG C. f. dRURY m. m. WANdER B. d. KAY Agriculture and Agri-food Canada Harrow Ontario N0R 1G0 (Canada). department of Natural Resources and Environmental Science University of Illinois at Urbana-Champaign Urbana IL61801 (USA) department of Land Resources University of Guelph Guelph Ontario N1G 2W1 (Canada)

Three long-term field trials in humid regions of Canada and the USA were used to evaluate the influence of soil depth and sample numbers on soil organic carbon (SOC) sequestration in no-tillage (NT) and moldboard plow (mP) corn (Zea mays L.) and soybean (Glycine max L.) production systems. The first trial was conducted on a maryhill silt loam (Typic Hapludalf) at Elora, Ontario, Canada, the second on a Brookston clay loam (Typic Argiaquoll) at Woodslee, Ontario, Canada, and the third on a Thorp silt loam (Argiaquic Argialboll) at Urbana, Illinois, USA. No-tillage led to significantly higher SOC concentrations in the top 5 cm compared to mP at all 3 sites. However, NT resulted in significantly lower SOC in sub-surface soils as compared to mP at Woodslee (10-20 cm, P = 0.01) and Urbana (20-30 cm, P d significantly more SOC storage than mP at the Elora site (3.3 mg C ha-1) and at the Woodslee site (6.2 mg C ha-1) on an equivalent mass basis (1350 mg ha-1 soil equivalent mass). Similarly, NT had greater SOC storage than mP at the Urbana site (2.7 mg C ha-1) on an equivalent mass basis of 675 mg ha-1 soil. However, these differences disappeared when the entire plow layer was evaluated for both the Woodslee and Urbana sites as a result of the higher SOC concentrations in mP than in NT at depth. Using the minimum detectable difference technique, we observed that up to 1500 soil sample per tillage treatment comparison will have to be collected and analyzed for the Elora and Woodslee sites and over 40 soil samples per tillage treatment comparison for the Urbana to statistically separate significant differences in the SOC contents of sub-plow depth soils. Therefore, it is impracticable, and at the least prohibitively expensive, to detect tillage-induced differences in soil C beyond the plow layer in various soils.

关键词： carbon sequestration minimum detectable difference moldboard plow no-tillage soil depth

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On the Simulation of Industrial Gas dynamic Applications with the disconti- nuous Galerkin Spectral Element method

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Journal of Thermal Science 2016年第3期25卷 250-257页

作者： f. Hempert m. Hoffmann U. Iben C.-d. munz Robert-Bosch GmbH Robert-Bosch Campus 1 71272 Renningen Germany Institute of Aerodynamics and Gas dynamics Pfaffenwaldring 21 70569 Stuttgart Germany

In the present investigation, we demonstrate the capabilities of the discontinuous Galerkin spectral element method for high order accuracy computation of gas dynamics. The internal flow field of a natural gas injector for bivalent combustion engines is investigated under its operating conditions. The simulations of the flow field and the aeroacoustic noise emissions were in a good agreement with the cxperirnental data. We tested several shockcapturing techniques for the discontinuous Galerkin scheme. Based on the validated framework, we analyzed the development of the supersonic jets during different opening procedures of a compressed natural gas injector. The results suggest that a more gradual injector opening decreases the noise emission.

关键词： discontinuous Galerkin natural gas injection supersonic under-expanded jet high performance computing

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first detailed Photometric Investigation on the Nature of Contact Binary System AA Cet

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Research in Astronomy and Astrophysics 2023年第7期23卷 154-163页

作者： m.f.Yıldırım f.Soydugan Çanakkale Onsekiz mart University Astrophysics Research Center and Ulupınar Observatory17020ÇanakkaleTurkey Çanakkale Onsekiz mart University Faculty of SciencesDepartment of Physics17020ÇanakkaleTurkey

The TESS light curve(LC)of the marginal contact binary A A Cet was analyzed simultaneously with the radial velocity and the orbital period(OP)change of the system was *** physical parameters of the system were obtained by analyzing the LC of A A Cet with the Wilson-devinney method,and the absolute parameters of the components were calculated using the results *** the components of AA Cet,the masses and radii were calculated as m_(1)=1.39±0.04 m_⊙,m_(2)=0.48±0.02 m_⊙,and R_(1)=1.64±0.03 R_⊙,R_(2)=1.01±0.04 R_⊙,*** Cet is a marginal contact binary with a temperature difference of 1305 K between its components.A total of 14 eclipse times were obtained from the TESS data and used in the OP analysis together with those collected from the *** has been observed that the change in the OP of AA Cet is in the form of a decreasing *** mass transfer between the components has been interpreted as the reason for this *** OP decrease amount of A A Cet was obtained as dP/dt=0.0062±0.0006 s yr^(-1).and the reason for this decrease was attributed to a 3.3(9)×10^(-8)m_⊙.mass transfer per year from the more massive component to the less massive *** age of A A Cet has been estimated as 7 Gyr,as the age of contact systems helps us to understand their evolution.

关键词： (stars:)binaries:eclipsing stars:fundamental parameters stars:individual(AA Cet)

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Effect of fire severity on physical and biochemical soil properties in Zagros oak(Quercus brantii Lindl.)forests in Iran

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Journal of forestry Research 2017年第1期28卷 95-104页

作者： m.Heydari A.Rostamy f.Najafi d.C.dey department of forest Science Faculty of Agriculture and Natural ResourcesIlam UniversityIlamIran department of forest Science Islamic Azad UniversityIlam BranchIlamIran Expert in forest Science Ilarn Natural Resources OfficeIlamIran Research forester Northern Research StationUSDA Fores tService202 Natural Resources BldgColumbiaMO 65211USA

fire affects the physical and chemical properties and soil biological activity of natural ecosystems. This study was conducted in the miyan Tang region, Ilam Province in western Iran. The study site was 110 hectares, where we sampled soils in areas that were classified by fire severity： low （LS）, high （HS） and medium severity （mS）, and unburned （UB）, which served as the control. In each severity class, 25 transect points were randomly selected for measurement. Around each transect plot center, 3 soil samples were selected randomly and soils collected from the 0 to 20 cm depth were combined into a composite sample that was used in laboratory analysis to represent conditions at that point. Plots in the UB and LS fire classes had similar soil conditions and had higher values of factors such as saturated moisture, organic carbon, carbon dioxide, and silt and clay content. In contrast, plots in the HS and mS fire severity classes were clustered in the positive direction along the first axis that represented gradients in soil acidity, electrical conductivity, cation exchange capacity, accessible phosphorus, accessible potassium, bulk density, and sand. Soil attributes were similar in areas of HS and mS fire severity classes, whereas soil conditions in the LS class and UB controls were most similar. fire in the LS areas either did not significantly alter the physicalchemical soil properties and microbial basal respiration, or soils were able to recover quickly after being burned.

关键词： fire severity Oak Soil respiration Physical and chemical soil properties

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dynamics of strong and radiative decays of d_s-mesons in the hadrogenesis conjecture

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Chinese Physics C 2010年第9期34卷 1320-1323页

作者： m.Soyeur m.f.m.Lutz Irfu/SPhN CEA/Saclay GSI Planckstrasse 1

The positive parity scalar d ＊ s0 （2317） and axial-vector d ＊ s1 （2460） charmed strange mesons are generated by coupled-channel dynamics through the s-wave scattering of Goldstone bosons off the pseudoscalar and vector d（d s ）-meson ground *** specific masses of these states are obtained as a consequence of the attraction arising from the Weinberg-Tomozawa interaction in the chiral *** corrections to order Q 2 χ are calculated and found to be *** d ＊ s0 （2317） and d ＊ s1 （2460） mesons decay either strongly into the isospin-violating π 0 d s and π 0 d ？ s channels or *** show that the π 0-η and （K^ 0 d ^＋-K^ ＋ d^ 0 ） mixings act constructively to generate strong widths of the order of 140 keV and emphasize the sensitivity of this value to the Kd component of the *** one-loop contribution to the radiative decay amplitudes of scalar and axial-vector states is calculated using the electromagnetic Lagrangian to chiral order Q 2 χ .We show the importance of taking into account processes involving light vector mesons explicitly in the dynamics of electromagnetic *** radiative width are sensitive to both η d s and Kd components,hence providing information complementary to the strong widths on the positive parity d s-meson structure.

关键词： charmed mesons d*s0 (2317) d*s1 (2460)

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Interactive data styling and multifocal visualization for a multigrid web-based digital Earth

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International Journal of digital Earth 2021年第3期14卷 288-310页

作者： m.J.Sherlock m.Hasan f.f.Samavati department of Computer Science University of CalgaryCalgaryCanada

Globe-based digital Earth(dE)is a promising system that uses 3d models of the Earth for integration,organization,processing,and visualization of vast multiscale geospatial *** growing size and scale of geospatial datasets present significant obstacles to interactive viewing and meaningful visualizations of these dE *** address these challenges,we present a novel web-based multiresolution dE system using a hierarchical discretization of the globe on both server and client *** presented web-based system makes use of a novel data encoding technique for rendering large multiscale geospatial datasets,with the additional capability of displaying multiple simultaneous *** the data needed for the current views and scales are encoded and *** leverage the power of GPU acceleration on the client-side to perform real-time data rendering and dynamic *** rendering of multiple views allows us to support multilevel focus+context visualization,an effective approach to navigate through large multiscale global *** client–server interaction as well as the data encoding,rendering,styling,and visualization techniques utilized by our presented system contribute toward making dE more accessible and informative.

关键词： digital Earth discrete Global Grid System data integration data fusion multilevel focus+context visualization spatial resolution context awareness

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Converting TREx-RGB green-channel data to 557.7 nm auroral intensity:methodology and initial results

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Earth and Planetary Physics 2024年第1期8卷 258-274页

作者： Jun Liang d.m.Gillies E.Spanswick E.f.donovan University of Calgary CalgaryT2N 1N4Canada

The recently deployed Transition Region Explorer(TREx)-RGB(red-green-blue)all-sky imager(ASI)is designed to capture“true color”images of the aurora and *** the 557.7 nm green line is usually the brightest emission line in visible auroras,the green channel of a TREx-RGB camera is usually dominated by the 557.7 nm *** this rationale,the TREx mission does not include a specific 557.7 nm imager and is designed to use the RGB green-channel data as a proxy for the 557.7 nm *** this study,we present an initial effort to establish the conversion ratio or formula linking the RGB green-channel data to the absolute intensity of 557.7 nm auroras,which is crucial for quantitative uses of the RGB *** illustrate two approaches:(1)through a comparison with the collocated measurement of green-line auroras from the TREx spectrograph,and(2)through a comparison with the modeled green-line intensity according to realistic electron precipitation flux measurements from low-Earth-orbit satellites,with the aid of an auroral transport *** demonstrate the procedures and provide initial results for the TREx-RGB ASIs at the Rabbit Lake and Lucky Lake *** RGB response is found to be *** conversion ratios or formulas between RGB green-channel data and the green-line auroral intensity are given and can be applied immediately by TREx-RGB data *** methodology established in this study will also be applicable to the upcoming SmILE ASI mission,which will adopt a similar RGB camera system in its deployment.

关键词： TREx RGB green-line aurora auroral transport model

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motion of a spherical particle in a fluid forced vortex by dQm and dTm

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Particuology 2014年第5期12卷 206-212页

作者： m.Hatami d.d.Ganji Esfarayen University Department of Mechanical EngineeringEsfarayenNorth KhorasanIran mechanical Engineering faculty Babol University of TechnologyBabolP.O.Box 484Iran

In this study, coupled equations of the motion of a particle in a fluid forced vortex were investigated using the differential transformation method （dTm） with the Pad6 approximation and the differential quadrature method （dO_m）. The significant contribution of the work is the introduction of two new, fast and efficient solutions for a spherical particle in a forced vortex that are improvements over the previous numerical results in the literature. These methods represent approximations with a high degree of accuracy and minimal computational effort for studying the particle motion in a fluid forced vortex. In addition, the velocity profiles （angular and radial） and the position trajectory of a particle in a fluid forced vortex are described in the current study.

关键词： Spherical particle forced vortex differential transformation method (dTm)Angular velocity differential quadrature method (dQm)

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An Iterative Relaxation Approach to the Solution of the Hamilton-Jacobi-Bellman-Isaacs Equation in Nonlinear Optimal Control

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IEEE/CAA Journal of Automatica Sinica 2018年第1期5卷 360-366页

作者： m.d.S.Aliyu department of Electrical Engineering King Faisal University Al-Ahsa 31982 Saudi Arabia IEEE

In this paper, we propose an iterative relaxation method for solving the Hamilton-Jacobi-Bellman-Isaacs equation(HJBIE) arising in deterministic optimal control of affine nonlinear systems. Local convergence of the method is established under fairly mild assumptions, and examples are solved to demonstrate the effectiveness of the method. An extension of the approach to Lyapunov equations is also discussed. The preliminary results presented are promising, and it is hoped that the approach will ultimately develop into an efficient computational tool for solving the HJBIEs.

关键词： Affine nonlinear system bounded continuous function convergence Hamilton-Jacobi-Bellman-Isaacs equation Lyapunov equation relaxation method Riccati equation

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Plasma formed in Argon,Acid Nitric and Water Used in Industrial ICP Torches

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Plasma Science and Technology 2012年第8期14卷 683-692页

作者： f.BENdJEBBAR P.ANdRE m.BENBAKKAR d.ROCHETTE S.fLAZI d.VACHER LGEO Oran UniversityBP1505El Mnaouer ORANAlgerie Blaise Pascal University LAEPTBP 10448F-63000 CLERMONT-FERRANDFrance Blaise Pascal University LMVBP 10448F-63000 CLERMONT-FERRANDFrance

Inductively coupled plasmas （ICPs） are used in spectrochemical analyses. The introduction of the sample by means of an aerosol are widely used. The introduction and the total evaporation of the aerosol is required in order to obtain a good repeatability and reproducibility of analyses. To check whether the vaporization of the aerosol droplets inside the plasma is completed, a solution could be used to compare the experimental results of the emission spectral lines with theoretical results. An accurate calculation code to obtain monatomic spectral lines intensities is therefore required, which is the purpose of the present paper. The mixtures of argon, water and nitric acid are widely used in spectrochemical analyses with ICPs. With these mixtures, we calculate the composition, thermodynamic functions and monatomic spectral lines intensities of the plasma at thermodynamic equilibrium and at atmospheric pressure. To obtain a self sufficient paper and also to allow other researchers to compare their results, all required data and a robust accurate algorithm, which is simple and easy to compute, are given.

关键词： inductively coupled plasmas argon plasma monatomic spectral lines ther-modynamic properties thermal plasma

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