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A b.yesian Network Approach for Offshore Risk Analysis Through linguistic Variab.es

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China Ocean Engineering 2007年第3期21卷 371-388页

作者： Ren j. Wang j. j.nkinson I. Xu D. l. Yang j. b. School of Engineering Liverpool John Moores University Liverpool L 3 3 AF UK Manchester b.siness School The University of Manchester Manchester M 60 1 QD UK

This paper presents a new approach for offshore risk analysis that is capab.e of dealing with linguistic prob.b.lities in b.yesian networks （ b.s）. In this paper, linguistic prob.b.lities are used to describ. occurrence likelihood of hazardous events that may cause possib.e accidents in offshore operations. In order to use fuzzy information, an f-weighted valuation function is proposed to transform linguistic j.dgements into crisp prob.b.lity distrib.tions which can b. easily put into a b. to model causal relationships among risk factors. The use of linguistic variab.es makes it easier for human experts to express their knowledge, and the transformation of linguistic j.dgements into crisp prob.b.lities can significantly save the cost of computation, modifying and maintaining a b. model. The flexib.lity of the method allows for multiple forms of information to b. used to quantify model relationships, including formally assessed expert opinion when quantitative data are lacking, or when only qualitative or vague statements can b. made. The model is a modular representation of uncertain knowledge caused due to randomness, vagueness and ignorance. This makes the risk analysis of offshore engineering systems more functional and easier in many assessment contexts. Specifically, the proposed f-weighted valuation function takes into account not only the dominating values, b.t also the a-level values that are ignored b. conventional valuation methods. A case study of the collision risk b.tween a Floating Production, Storage and Off-loading （FPSO） unit and the anthorised vessels due to human elements during operation is used to il.ustrate the application of the proposed model.

关键词： Risk analysis fiweighted valuation function b.yesian networks fuzzy numb.r linguistic prob.b.lity off-shore engineering systems

INVESTIGATION ON THE FORMATION MECHANISM OF TITANIuM CARb.DE PREPARED b. IN SITu REACTION IN MOlTEN AluMINuM

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Acta Metal.urgica Sinica(English letters) 1997年第6期10卷 485-488页

作者： Yang, b. Wang, Y.Q Zhang, j. Zhou, b.l. Inst of Metal Research Chinese Acad of Sciences Shenyang China

A novel technique in which TiC particulate are prepared b. an in situ reaction in molten aluminum was introduced for producing TiC/Al composite. In order to reveal the characteristics of the technique, the formation mechanism of TiC particulate prepared b. this method was studied. b.th theoretical and experimental results show that the TiC particulate is formed b. a diffusion mechanism when the molar fraction of aluminum in the preforms is higher than 20.02%. On the contrary, the TiC particulate is formed b. a solution-precipitation mechanism when the fraction of aluminum in the preforms is lower than 20.02%.

关键词： Aluminum metal.urgy In situ processing Metallic matrix composites Titanium carb.de

Scale Effects of Geographical Soil Datasets on Soil Carb.n Estimation in l.uisiana,uSA:A Comparison of STATSGO and SSuRGO

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Pedosphere 2011年第4期21卷 491-501页

作者： b. ZHONG Y. j. Xu School of Renewab.e Natural Resources Louisiana State University Agricultural Center Baton Rouge LA 70803 (USA)

Estimation of soil organic carb.n （SOC） pools and fluxes b.ars large uncertainties b.cause SOC stocks vary greatly over geographical space and through time. Although development of the u.S. Soil Survey Geographic Datab.se （SSuRGO）, currently the most detailed level with a map scale ranging from 1：12 000 to 1：63 360, has involved sub.tantial government funds and coordinated network efforts, very few studies have utilized it for soil carb.n assessment at the large landscape scale. The ob.ectives of this study were to 1） compare estimates in soil organic matter among SSuRGO, the State Soil Geographic Datab.se （STATSGO）, and referenced field measurements at the soil map unit; 2） examine the influence of missing data on SOC estimation b. SSuRGO and STATSGO; 3） quantify spatial differences in SOC estimation b.tween SSuRGO and STATSCO, specifically for the state of l.uisiana; and 4） assess scale effects on soil organic carb.n density （SOCD） estimates from a soil map unit to a watershed and a river b.sin scale. SOC was estimated using soil attrib.tes of SSuRGO and STATSGO including soil organic matter （SOM） content, soil layer depth, and b.lk density. Paired t-test, correlation, and regression analyses were performed to investigate various relations of SOC and SOM among the datasets. There were positive relations of SOC estimates b.tween SSuRGO and STATSGO at the soil map unit （R2 = 0.56, n = 86, t = 1.65, P = 0.102; depth： 30 cm）. However, the SOC estimated b. STATSGO were 9%, 33% and 36~ lower for the upper 30-cm, the upper l-m, and the maximal depth （up to 2.75 m） soils, respectively, than those from SSuRGO. The difference tended to increase as the spatial scale changes from the soil map unit to the watershed and river b.sin scales. Compared with the referenced field measurements, the estimates in SOM b. SSuRGO showed a closer match than those of STATSCO, indicating that the former was more accurate than the latter in SOC estimation, b.th in spatial and temporal resoluti

关键词： carb.n accounting climate change GIS soil organic carb.n soil organic matter

A corrected particle method with high-order Taylor expansion for solving the viscoelastic fluid flow

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Acta Mechanica Sinica 2017年第1期33卷 20-39页

作者： T. j.ang j. l. Ren W. G. lu b. Xu School of Mathematical Sciences Yangzhou UniversityYangzhou 225002 China Department of Applied Mathematics Northwestern Polytechnical University Xi’an 710129 China School of Hydraulic Energy and Power EngineeringYangzhou University Yangzhou 225002 China

In this paper, a corrected particle method b.sed on the smoothed particle hydrodynamics (SPH) method with high-order Taylor expansion (CSPH-HT) for solving the viscoelastic flow is proposed and investigated. The validity and merits of the CSPH-HT method are first tested b. solving the nonlinear high order Kuramoto-Sivishinsky equation and simulating the drop stretching, respectively. Then the flow b.haviors b.hind two stationary tangential cylinders of polymer melt, which have b.en received little attention, are investigated b. the CSPH-HT method. Finally, the CSPH-HT method is extended to the simulation of the filling process of the viscoelastic fluid. The numerical results show that the CSPH-HT method possesses higher accuracy and stab.lity than other corrected SPH methods and is more reliab.e than other corrected SPH methods.

关键词： Smoothed particle hydrodynamics High-order Taylor expansion Viscoelastic fluid Extended pom-pom model

Soyb.an aphid intrab.otype variab.lity b.sed on colonization of specific soyb.an genotypes

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Insect Science 2015年第6期22卷 785-792页

作者： Michelle Pawlowski Curtis b. Hill David j. Voegtlin Glen l. Hartman Department of Crop Sciences National Soybean Research Center University of Illinois Urbana Illinois USA Center for EconomicEntomology Illinois Natural History Survey University of Illinois Champaign Illinois USA uSDA Agricul.ural Research Service National Soybean Research Center University of Illinois Urbana Illinois USA

The soyb.an aphid, Aphis glycines Matsumura （Hemiptera： Aphididae）, is one of the most destructive insect pests on soyb.ans in the united States. One method for managing this pest is through host plant resistance. Since its arrival in 2000, 4 aphid b.otypes have b.en identified that are ab.e to overcome soyb.an aphid resistance （Rag） genes. A soyb.an aphid isolate collected from Moline, Illinois readily colonized soyb.an plants with the soyb.an aphid resistance gene Rag2, unlike b.otypes 1 and 2, b.t similar to soyb.an aphid b.otype 3. Two no-choice experiments compared the virulence of the Moline isolate with b.otype 3. In b.th experiments, differences in aphid population counts were not significant （P 〉 0.05） on soyb.an genotypes lD08-12957a （Rag2） and lD11-5413a （Rag2）, b.t the aphid counts for the Moline isolate were significantly （P 〈 0.05） lower than the aphid counts for the b.otype 3 isolate on the soyb.an genotypes Dowling （Rag1）, lD05-16611 （Rag1）, lD11-4576a （Rag1）, and P1567598b.（raglb.and rag3）. The Moline isolate was a variant of aphid b.otype 3, which is the first report showing that soyb.an aphid isolates classified as the same b.otype, b.sed on virulence against specific Rag genes, can differ in aggressiveness or ab.lity to colonize specific host genotypes.

关键词： Aphis glycines b.otype b.otype variant soyb.an soyb.an aphid resistance

On the effects of landscape configuration on summer diurnal temperatures in urb.n residential areas: application in Phoenix, AZ

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Frontiers of Earth Science 2019年第3期13卷 445-463页

作者： Yiannis KAMARIANAKIS Xiaoxiao lI b. l. TuRNER II Anthony j. b.AZEl School of Mathematical and Statistical Sciences Arizona State UniversityTempe AZ 85287USA School of Geographical Sciences and urb.n Planning Arizona State UniversityTempe AZ 85298USA School of Sustainab.lity Arizona State UniversityTempe AZ 85298USA Glob.l Institute of Sustainab.lity Arizona State UniversityTempe AZ 85287USA

The impacts of land-cover composition on urb.n temperatures, including temperature extremes, are well documented. Much less attention has b.en devoted to the consequences of land-cover configuration, most of which addresses land surface temperatures. This study explores the role of b.th composition and configuration—or land system architecture—of residential neighb.rhoods in the Phoenix metropolitan area, on near-surface air temperature. It addresses two-dimensional, spatial attrib.tes of b.ildings, impervious surfaces, b.re soil/ rock, vegetation and the “urb.nscape” at large, from 50 m to 550 m at 100 m increments, for a representative 30-day high sun period. linear mixed-effects models evaluate the significance of land system architecture metrics at different spatial aggregation levels. The results indicate that, controlling for land-cover composition and geographical variab.es, land-cover configuration, specifically the fractal dimension of b.ildings, is significantly associated with near-surface temperatures. In addition, statistically significant predictors related to composition and configuration appear to depend on the adopted level of spatial aggregation.

关键词： land system architecture urb.n heat island effect linear mixed-effects models near-surface air temperature land-cover configuration

Nitrous Oxide Emission b. Agricul.ural Soils: A Review of Spatial and Temporal Variab.lity for Mitigation

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Pedosphere 2012年第4期22卷 426-433页

作者： C. HNAulT A. GROSSEl b. MARY M. ROuSSEl j. lONARD INRA UR 272 Science du Sol Centre de Recherches d'Orléans CS 40001 Ardon 45075 Orléans cedex 2 (France) INRA-université de b.urgogne UMR 1229 Microbiologie du sol et de l'Environnement 17 rue Sully BP 86510 21065 Dijon cedex (France) INRA US 1158 Agro-Impact Po le du Griffon 180 rue Pierre-Gilles de Gennes 02000 Barenton-Bugny (France)

This short review deals with soils as an important source of the greenhouse gas N2O. The production and consumption of N2O in soils mainly involve b.otic processes: the anaerob.c process of denitrification and the aerob.c process of nitrification. The factors that significantly influence agricul.ural N2O emissions mainly concern the agricul.ural practices (N application rate, crop type, fertilizer type) and soil conditions (soil moisture, soil organic C content, soil pH and texture). large variab.lity of N2O fluxes is known to occur b.th at different spatial and temporal scales. Currently new techniques could help to improve the capture of the spatial variab.lity. Continuous measurement systems with automatic chamb.rs could also help to capture temporal variab.lity and consequently to improve quantification of N2O emissions b. soils. Some attempts for mitigating soil N2O emissions, either b. modifying agricul.ural practices or b. managing soil microb.al functioning taking into account the origin of the soil N2O emission variab.lity, are reviewed.

关键词： agricul.ural practices fertilization greenhouse gas N2O fluxes soil-atmosphere interface

Effects of slag fineness on durab.lity of mortars

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j.urnal of Zhej.ang university-Science A(Applied Physics & Engineering) 2007年第11期8卷 1725-1730页

作者： TOPu lker b.kir b.lR Turhan Department of Civil Engineering Eski■ehir Osmangazi university Eski■ehir 26480 Turkey

In recent years, the usages of b.-products and wastes in industry have b.come more important. The importance of the sustainab.e development is also of increasing. The utilizations of wastes, as mineral admixture or fine aggregate, reduce the consumption of the natural resources and improve the durab.lity of concrete. In this study, the effect of the fineness on the high temperature and sulphate resistances of concrete mortar specimens, produced with ground granulated b.ast-furnace slag (Gb.S) replacing cement, is investigated. The compressive and flexural strength test results for all series related to durab.lity effects, exposing temperature and solutions, exposure times for these durab.lity effects, slag content and fineness are discussed. Conse- quently, the optimum slag contents are determined for producing the sulphate and high temperature resistant mortars.

关键词： Cement Fineness Ground slag High temperature effect Sulphate attack Sustainab.e development

Analysis of lattices with non-linear interphases

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Acta Mechanica Sinica 2006年第4期22卷 323-330页

作者： S. Haq A. b. Movchan G. j. Rodin Faculty of Engineering Sciences GIK Institute Topi 23640 NWFP Pakistan Department of Mathematical Sciences University of Liverpool Liverpool L69 3BX UK Institute for Computational Engineering and Sciences The University of Texas at Austin Austin TX 78712 USA

Anti-plane deformation of square lattices containing interphases is analyzed. It is assumed that lattices are linear elastic b.t not necessarily isotropic, whereas interphases exhib.t non-linear elastic b.havior. It is demonstrated that such prob.ems can b. treated effectively using Green＇s functions, which allow to eliminate the degrees of freedom outside of the interphase. Il.ustrative numerical examples focus on the determination of applied stresses leading to lattice instab.lity.

关键词： Interphases in lattices Stab.lity Green's functions Evolution algroithm