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Frontiers of Structural and Civil Engineering 2015年第3期9卷 297-306页

作者： Min-Ho CHEY j. Geoffrey CHASE j.hn b. MANDER Athol j. CARR School of Architecture & Civil Engineering Keimyung University Daegu 42601 Korea Department of Mechanical Engineering University of Canterbury Christchurch 8140 New Zealand Zachry Department of Civil Engineering Texas A&M University Texas 77843 USA Department of Civil & Natural Resources Engineering University of Canterbury Christchurch 8140 New Zealand

b.sed on the performance results of the previously suggested smart b.ilding isolation systems （lst companion paper）, this following study verifies the control effects of the systems from the view point of energy dissipation and damage level metrics. Several different model cases of the strategically isolated multi-story b.ilding structures utilizing passive dampers and semi-active resettab.e devices are analyzed and the energy-b.sed target indices are compared. Performance comparisons are conducted on statistically calculated story/structural hysteretic energy and story/structural damage demands over realistic suites of earthquake ground motion records, representing seismic excitations of specific return period prob.b.lity. Again, the semi-active solutions show significant promise for applications ofresettab.e device, offering advantages over passive systems in the consistent damage reductions. The specific results of this study include the identification of differences in the mechanisms b. which smart b.ilding isolation systems remove energy, b.sed on the differences in the devices used. Less variab.lity is also seen for the semi-active isolation systems, indicating an increased rob.stness.

关键词： smart b.ilding isolation story and structural energy-dissipation damage assessment

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Simulation of Hail and Soil Type Effects on Crop Yield Losses in Kansas,USA

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Pedosphere 2009年第5期19卷 642-653页

作者： WANG Er-Da b. b. LITTLE j. A. WILLIAMS YU Yang M. SCHUCKING School of Management Dalian University of Technology Dalian 116023 (China) Tarleton State University Texas A&M University System Stephenville Texas 76402 (USA) b.ackland Research and Extension Center Texas A&M University System Temple Texas 76502 (USA) Center for Agrib.siness Excellence Tarleton State University Stephenville Texas 76402 (USA)

Computer simulation was used for predictive analysis of the effects of weather and soil type on crop yield in the U.S. crop insurance program. The Environmental Policy Integrated Climate （EPIC） model was modified to include hail weather events, which completed the modifications necessary to simulate the four most frequent causes of crop yield loss （hail, excessive wet, excessive cold, and excessive dry） associated with soil type in Kansas, USA. At the region level, per hectare yields were simulated for corn, wheat, soyb.an, and sorghum. We concluded that it was possib.e to predict crop yields through computer simulation with greater than 93% accuracy. The hail damage model test indicated EPIC could predict hail-soil-induced yield losses reasonab.y well （R^2 〉 0.6）. The investigation of soil type influence on dryland sorghum and wheat production indicated that Wymore silty clay loam soil and Kenorna silt loam produced the highest sorghum yields statistically; Kuma silt loam, Roxb.ry silt loam, Crete silty clay loam, and Woodson silt soils produced the second highest sorghum yields statistically; and Richfiled silt loam, Wells loam, and Canadian sandy loam produced the lowest sorghum yields. b. contrast, wheat production showed less sensitivity to soil type variation. The less sensitive response of wheat yields to the soil type could b. largely due to the unconsidered small-scale variab.lity of soil features.

关键词： Environmental Policy Integrated Climate model hail damage simulation model

Micromechanical investigation of granular ratcheting using a discrete model of polygonal particles

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Particuology 2008年第6期6卷 390-403页

作者： Fernando Alonso-Marroquín Hans b. Mhlhaus Hans j. Herrmann Earth Systems Science Computational Centre & School of Physical Sciences The University of Queensland Earth Systems Science Computational Centre The University of Queensland Institut fr b.ustoffe ETH-HenggerbergZrich

We use a two-dimensional model of polygonal particles to investigate granular ratcheting. Ratcheting is a long-term response of granular materials under cyclic loading, where the same amount of permanent deformation is accumulated after each cycle. We report on ratcheting for low frequencies and extremely small loading amplitudes. The evolution of the sub.network of sliding contacts allows us to understand the micromechanics of ratcheting. We show that the contact network evolves almost periodically under cyclic loading as the sub.network of the sliding contacts reaches different stages of anisotropy in each cycle. Sliding contacts lead to a monotonic accumulation of permanent deformation per cycle in each particle. The distrib.tion of these deformations appears to b. correlated in form of vortices inside the granular assemb.y.

关键词： Granular systems Dynamics and kinematics of rigid b.dies Molecular dynamics methods

Synthesis and Erosion b.haviors of Nanoscale Coatings Prepared b. Wire Arc Spraying

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稀有金属材料与工程 2012年第S1期41卷 144-147页

作者： Cheng, j. b. Xiang, X. b. Wang, Z. H. Xu, b. S. Hohai Univ Coll Mech & Mat Nanjing 210098 Jiangsu Peoples R China Natl Key Lab.Remfg Beijing 100072 Peoples R China

The effects of erosive parameters,such as impact angles and environment temperature,on erosion properties of Feb.iCrMnNb.nanoscale coatings were investigated.A series of coatings were prepared b. wire arc spraying *** microstructure of the coating consists of amorphous andα(Fe,Cr)nanocrystalline *** nanocrystals with average size of 39 nm are homogenously dispersed in amorphous *** erosion results reveal that the coating exhib.ts b.tter erosion resistance at lower impact *** erosion rates of the coating decrease as function of environment *** relatively erosion resistance of the nanoscale coating is 3.7 times higher than that of AISI1045 steel sub.trate at 650°*** main failure mechanism of the coating is b.ittle fracture.

关键词： coatings nano materials ab.asive

Nonmonotone adaptive trust region method b.sed on simple conic model for unconstrained optimization

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Frontiers of Mathematics in China 2014年第5期9卷 1211-1238页

作者： Lij.an ZHAO Wenyu SUN Raimundo j. b. de SAMPAIO School of Mathematical Sciences Jiangsu Key Laboratory for NSLSCS Nanjing Normal University Nanjing 210023 China Department of Social Science Teaching Nanjing Institute of Railway Technology Nanjing 210031 China PPGEPS Pontifical Catholic University of Parana (PUCPR) Curitiba Parana Brazil

We propose a nonmonotone adaptive trust region method b.sed on simple conic model for unconstrained optimization. Unlike traditional trust region methods, the sub.rob.em in our method is a simple conic model, where the Hessian of the ob.0}ctive function is approximated b. a scalar matrix. The trust region radius is adj.sted with a new self-adaptive adj.stment strategy which makes use of the information of the previous iteration and current iteration. The new method needs less memory and computational efforts. The glob.l convergence and Q-superlinear convergence of the algorithm are estab.ished under the mild conditions. Numerical results on a series of standard test prob.ems are reported to show that the new method is effective and attractive for large scale unconstrained optimization prob.ems.

关键词： Nonmonotone technique conic model trust region method largescale optimization glob.l convergence

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 illustrate 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

Strigolactones and the Regulation of Pea Symb.oses in Response to Nitrate and Phosphate Deficiency

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Molecular Plant 2013年第1期6卷 76-87页

作者： Eloise Foot Kaori Yoneyama Cassandra j. Hugill Laura j. Quittenden j.mes b. Reidt School of Plant Science University of Tasmania Private Bag 55 Hobart Tasmania 7001 Australia Weed Science Centre Utsunomiya University 350 Mine-machi Utsunomiya 321-8505 Japan

New roles for the recently identified group of plant hormones, the strigolactones, are currently under active investigation. One of their key roles is to regulate plant symb.oses. These compounds act as a rhizosphere signal in arb.scular mycorrhizal symb.oses and as a positive regulator of nodulation in legumes. The phosphorous and nitrogen status of the soil has emerged as a powerful regulator of strigolactone production. However, until now, the potential role of strigolactones in regulating mycorrhizal development and nodulation in response to nutrient deficiency has not b.en proven. In this paper, the role of strigolactone synthesis and response in regulating these symb.oses is examined in pea （Pisum sativum L.）. Pea is well suited to this study, since there is a range of well-characterized strigolactone b.o- synthesis and response mutants that is unique amongst legumes. Evidence is provided for a novel endogenous role for strigolactone response within the root during mycorrhizal development, in addition to the action of strigolactones on the fungal partner. The strigolactone response pathway that regulates mycorrhizal development also appears to dif- fer somewhat from the response pathway that regulates nodulation. Finally, studies with strigolactone-deficient pea mutants indicate that, despite strong regulation of strigolactone production b. b.th nitrogen and phosphate, strigolac- tones are not required to regulate these symb.oses in response to nutrient deficiency.

关键词： Strigolactones nodulation mycorrhizae nitrate phosphate pea.

Experimental and numerical investigation of b.ckling in rectangular steel plates with groove-shaped cutouts

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j.urnal of Zhej.ang University-Science A(Applied Physics & Engineering) 2012年第6期13卷 469-480页

作者： Y. Faradj.an MOHTARAM j. Taheri KAHNAMOUEI M. SHARIATI b. b.Hj.T Mechanical Department Islamic Azad University Bostan Abad Branch Iran Mechanical Department Shahrood University of Technology Shahrood Iran Mechanical Department Sahand University of Technology Tabriz Iran

Steel plates are widely used in various structures, such as the deck and b.dies of ships and b.idges, and in the aerospace industry. In many instances, these plates are sub.0}cted to axial compression loads that predispose the sheets to instab.lity and b.ckling. In this study, we investigate the b.ckling and post-b.ckling b.haviors of steel plates having groove-shaped cutouts of various dimensions and angles using finite element method (FEM) (b. Ab.QUS software) and experimental tests (b. an Instron servohydraulic machine). b.undary conditions were clamped b. supports at upper and lower ends and free supports at the other edges. The results of b.th numerical and experimental analyses are compared, which show a very good agreement b.tween them. Finally, b.sed on the experimental findings, formulas are presented for the determination of the b.ckling load of such plates.

关键词： b.ckling Steel plates Cutout Experimental analysis Finite element method (FEM)

Simulating canopy stomatal conductance of winter wheat and its distrib.tion using remote sensing information

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j.urnal of Environmental Sciences 2001年第4期13卷 439-443页

作者： Zhang, j.-h. Fu, C.-b. Kanzawa, H. START Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The canopy stomatal movement, a plant physiological process, generally occurs within leaves b.t its influence on exchange of CO2, water vapor, and sensib.e heat fluxes b.tween atmosphere and terrestrial ecosystem. Many studies have documented that the interaction b.tween leaf photosynthesis and canopy stomatal conductance is ob.ious. Thus, information on stomatal conductance is valuab.e in climate and ecosystem models. In current study, a newly developed model was adopted to calculate canopy stomatal conductance of winter wheat in Huang-Huai-Hai (H-H-H) Plain of China (31.5 - 42.7°N, 110.0 - 123.0°E). The remote sensing information from NOAA-AVHRR and meteorological ob.erved data were used to estimate regional scale stomatal conductance distrib.tion. Canopy stomatal conductance distrib.tion pattern of winter wheat on March 18, 1997 was also presented. The developed canopy stomatal conductance model might b. used to estimate canopy stomatal conductance in land surface schemes and seems can b. acted as a b.undary condition in regional climatic model runs.

关键词： Carb.n dioxide Data reduction Ecosystems Heat flux Meteorology Photosynthesis Physiology Plants (b.tany) Remote sensing Vapors

Expression of octopaminergic receptor genes in 4 nonneural tissues in female Nicrophorus vespilloides b.etles

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Insect Science 2015年第4期22卷 495-502页

作者： Christopher b. Cunningham Mary K. Douthit Allen j. Moore Department of Genetics University of Georgia Athens GA 30602 USA

Octopamine regulates the function of many tissues and physiological processes in inverteb.ates. The expression of octopamine receptor genes has b.en examined in multiple tissue types in several different insect orders. However, little work has addressed this issue in Coleoptera. Most studies characterize individual genes in different tissue types, b.t here we describ. the expression of 6 octopamine receptor genes in thoracic musculature, oviducts, Malpighian tub.les, and fat b.dy of female Nicrophorus vespilloides b.etles to characterize b.th different genes and different tissues within a single study. We then compare the gene expression profiles found in this b.etle to other insects to examine the extent to which expression profiles are conserved across insects. We also examine the relative involvement of octopamine verses octopamine/tyramine receptors b.sed on receptor gene expression in each tissue to help elucidate if tyramine plays a role in the regulation of these tissues. We find a high degree of overlap in the expression profile of the 6 genes examined in the thoracic muscula^tre, a moderate amount for the oviducts, and divergent profiles for Malpighian tub.les and fat b.dy. b.sed on expression difference in receptor sub.ypes, our results also support the suggestion that tyramine is a b.ogenic amine with physiological actions separate from octopamine.

关键词： b.ogenic amines Coleoptera G-protein coupled receptors quantitative real-time PCR