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A New Perspective of the Physical Processes Associated with the Clear-Sky Greenhouse Effect over High Latitudes

Advances in Atmospheric Sciences 2004年第2期21卷 171-180页

作者： Zuohao ca0 ronald E．STEWArT M．K．YAU MeteorologicalServiceofcanada，Ontario，canada DepartmentofAtmosphericandOceanicSciences，McGillUniversityMontreal，Quebec，canada

The physical processes associated with the clear-sky greenhouse effect in the presence of water vapor are examined by including surface emissivity in the greenhouse effect formulation, and by introducing a new way to partition physical processes of the greenhouse effect. In this new framework, it is found that the clear-sky greenhouse effect is governed by three physical processes associated with (1) the temperature contrast between the surface and the atmosphere, (2) the interaction between the surface emissivity and the temperature contrast, and (3) the surface emissivity. The importance of the three physical processes is assessed by computing their vertical and spectral variations far the subarctic winter and summer standard atmosphere using the radiation model MODTrAN3 (Moderate resolution Transmittance code Version 3). The results show that the process associated with the temperature contrast between the surface and the atmosphere dominates over the other two processes in magnitude. The magnitude of this process has substantial variations in the spectral region of 1250 to 1880 cm-1 and in the far infrared region. Due to the low-level temperature inversion over the subarctic winter, there exists a negative contribution to the greenhouse trapping. The seasonal variations are, however, dominated by the processes associated with the interaction between the surface emissivity and the temperature contrast as well as the surface emissivity itself. The magnitudes of these two physical processes contributing to the greenhouse trapping over the subarctic winter are about 7 to 10 times of those over the subarctic summer, whereas the magnitude of the processes associated with the temperature contrast in the subarctic summer is only about 2 times of that in the subarctic winter.

关键词： greenhouse effect surface ernissivity physical processe high latitude seasonal variation

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北祁连山高压变质带的变形和变质特征及其对俯冲带折返的意义

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岩石学报 2009年第9期25卷 2235-2246页

作者：曹毅宋述光 ca0 Peking Univ MOE Key Lab Orogen Belts & Crustal Evolut Dept Geol Beijing 100871 Peoples R China

北祁连造山带是早古生代大洋板块"冷"俯冲的典型地区,形成了一系列高压低温变质的岩石组合。基性榴辉岩是俯冲洋壳变质的产物,根据其结构构造特征可以划分为(1)粒状榴辉岩,峰期变质矿物组合为Grt+Omp+Phn+rut±Lws,硬柱石呈包裹体和假... 详细信息

北祁连造山带是早古生代大洋板块"冷"俯冲的典型地区,形成了一系列高压低温变质的岩石组合。基性榴辉岩是俯冲洋壳变质的产物,根据其结构构造特征可以划分为(1)粒状榴辉岩,峰期变质矿物组合为Grt+Omp+Phn+rut±Lws,硬柱石呈包裹体和假象分布于石榴石内,变质温压条件T=465～508℃,p=2.30～2.60GPa。(2)片状榴辉岩,岩石具片状构造,其共生矿物组合Omp+Czo/Ep+Phn+Gln构成透入性面理S_1和线理L_1,以及宏观和显微同斜褶皱F_1。其峰期变质温压条件为T=466～510℃,P=1.9～2.2GPa。(3)蓝片岩相退化变质榴辉岩,蓝片岩相变质矿物Gln+Ep+Phn±Ab强烈交代榴辉岩相矿物,并发生强烈D_2期变形作用,岩石形成明显的透入性面理S_2和线理L_2,以及同斜剪切褶皱F_2。蓝闪石和多硅白云母线理的统计揭示D_2期变形以斜向走滑剪切为主,与D_1期变形的榴辉岩的运动学特征大体相似。D_2同变质的温压条件为T=422～487℃,P=1.15～1.37GPa。高压变质带晚期的绿片岩相叠加和D_3期变形,形成透入性面理S_3和线理L_3,其运动特征为近于垂直构造线的逆冲剪切。结合榴辉岩变形特征,变质温压条件和同位素年代学资料,我们认为退变质的强弱与变形程度有密切关系。峰期变质后的榴辉岩经过早期绿帘石榴辉岩相到蓝片岩相斜向走滑剪切,和晚期绿片岩相逆冲,在泥盆纪早期快速折返的出露地表。

关键词：北祁连山高压变质带变形变质特征俯冲带折返 implications 榴辉岩相峰期变质温压条件 mineral assemblage 蓝片岩相 North Qilian Mountains isotopic geochronology 走滑剪切线理绿片岩相矿物组合变质矿物 movement Early Paleozoic

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Adaptive Agent-Based Modeling Framework for Collective Decision-Making in Crowd Building Evacuation

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Journal of Shanghai Jiaotong university(Science) 2021年第4期26卷 522-533页

作者： CHEN Feier ZHA0 Qiyuan ca0 Mingming CHEN Jiagi FU Guiguan State Key Laboratory of Ocean Engineering Key Laboratory of Marine Intelligent Equipment and System of Ministry of EducationShanghai Jiao Tong UniversityShanghai200240China Marautec Co. Ltd.Shanghai201206China Zhiyuan College Shanghai Jiao Tong UniversityShanghai200240China School of Mathematical Sciences Shanghai Jiao Tong UniversityShanghai200240China Institute of Fintech Shanghai University of Finance and EconomicsShanghai200433China

Crowd evacuation in different situations is an important topic in the research field of safety. This paper presents a hybrid model for heterogeneous pedestrian evacuation simulation. Our adaptive agent-based model (ABM) combines the strength of human crowd behavior description from classical social force models with discrete dynamics expression from cellular automaton models by extending the conception of floor field. Several important factors which may influence the results of decision-making of pedestrians are taken into consideration, such as the location of sign, the attraction of exit, and the interaction among pedestrians. To compare the effect of information on the pedestrians, we construct three decision-making mechanisms with different assumptions. To validate these three simulation models, we compare the numerical results from different perspectives with rational range in the case study where the Tampere Theater evacuation was carried out. The ABM framework is open for rules modification and could be applied to different building plans and has implication for architectural design of gates and signs in order to increase the evacuation efficiency.

关键词： adaptive agent-based model evacuation simulation emergency interaction heterogeneity

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Analysis and Modeling of Slope Stability in the Three-Gorges Dam reservoir (China)——The case of Huangtupo Landslide

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Journal of Mountain Science 2011年第2期8卷 166-175页

作者： r.COJEAN Y.J.ca Centre de Géosciences Mines-ParisTech Paris France Changjiang Institute of Survey Planning Design & Research CWRC Wuhan China

The water level in the Three Gorges Dam reservoir is expected to change between the elevations of 145 m and 175 m, as a function of the flood control implementation and the intensity of the annual flood. As a matter of fact, the hydraulical and mechanical loadings, related to the water level modifications, will result in alterations in the slope stability conditions. The town of Badong (Hubei), of 20 000 inhabitants, is one of the towns which was submerged by the impoundment of the reservoir. As a consequence, the new town of Badong was constructed on a nearby site which appeared to be partly an unstable site. A part of this site corresponds to an old landslide, the Huangtupo landslide, the base of which had to be submerged by the water of the reservoir. The analysis of the Huangtupo landslide, taking into account various events scenarios, drainage and reinforcement measures and monitoring devices, allows to illustrate the general process implemented all along the reservoir in order to mitigate the landslide hazard.

关键词： Three Gorges Dam Landslide Modelling

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STATE POLICY AND UrBAN SYSTEMS :THE caSE OF CHINA

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Journal of Geographical Sciences 1997年第1期7卷 1-10页

作者： YehuaWei DepartmentofGeography ,Universityofcalifornia LosAngeles LosAngeles,ca 90 0 2 4,USA

Thispaperusestherank sizemodelandtheexpansionmethodtoexaminethe changeofcity sizedistributioninChinafrom 1 95 2to 1 990 .Itrevealsthatafterashort periodofconcentration ,populationdeconcentrationamongcitieshasdominatedurban China .Thistrendhasevenbeenspeededupinthereformperiodsince 1 *** lishmentofalargeamountofnewcitieshaslargelycontributedtothetrendofdecreasing *** lishedcities,Chinesesystemofcitieswouldexperienceatrendofincreasedpopulation concentrationandpopulationintheupper rankcitiesgrewfasterthanthatinthelower rankcities.

关键词： urban systems urban policy rank -sizemodel expansion method China .

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ca19-9 antigen levels can distinguish between benign and malignant pancreaticobiliary disease

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Hepatobiliary & Pancreatic Diseases International 2009年第6期8卷 620-626页

作者： Gareth Morris-Stiff Mary Teli Nicky Jardine Malcolm ca Puntis Department of Surgery University Hospital of Wales

BACKGrOUND:ca19-9 is a carbohydrate tumor-associated antigen which is frequently upregulated in pancreatobiliary ***,it may also be elevated in patients with jaundice in the absence of a tumor due to biliary obstruction,and in other non-hepato-pancreatico-biliary *** study aimed to evaluate whether ca19-9 levels could accurately differentiate between benign and malignant pancreatobiliary ***:All patients referred to a single surgeon for investigation of pancreaticobiliary disease in 2003 in whom a firm diagnosis had been established were *** malignant disease,a histological diagnosis was required but for benign disease a firm radiological diagnosis was deemed *** patients were divided into 4 categories:pancreatic adenocarcinoma(Pca);cholangiocarcinoma(Cca);chronic pancreatitis(CP)and biliary calculous disease(calc).Bilirubin and alkaline phosphatase levels corresponding to the point of assessment of ca19-9 were also ***:Final diagnoses were made of pancreatic adenocarcinoma(Pca,n=73),cholangiocarcinoma(Cca,n=19),ampullary carcinoma(Amp,n=7),neuroendocrine carcinoma(Neu,n=4),duodenal carcinoma(Duo,n=3),chronic pancreatitis(CP,n=115),and biliary calculous disease(calc,n=27).Median ca19-9 levels(U/ml)were:Pca,653;Cca,408;Duo,403;calc,27;CP,19;Neu,10.5;Amp,8(reference range:0-37).The ca19-9 levels were significantly greater for malignant than for benign disease,could differentiate Pca from Cca/Duo,and were significantly higher in unresectable than in resectable *** sensitivity,specificity,positive predictive value(PPV)and negative predictive value(NPV)for ca19-9 were 84.9%,69.7%,67.7%and 86.1%,respectively.A rOC analysis provided an area under the curve for ca19-9 of 0.871(0.820-0.922),giving an optimal ca19-9 of 70.5 U/ml for differentiating benign from malignant *** this cut-off,the sensitivity was 82.1%,while specificity,PPV and NPV improved to 85.9%,81.3%and 86.5%,*** sta

关键词： ca19-9 antigen pancreatic disease biliary tract disease malignant benign

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Modelling ballistic impact on military helmets:The relevance of projectile plasticity

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Defence Technology（防务技术） 2021年第5期17卷 1699-1711页

作者： A.caçoilo r.Mourao F.Teixeira-Dias A.Azevedo F.Coghe r.A.F.Valente School of Engineering The University of EdinburghEdinburghEH93FGUK Dept.Weapon Systems and Ballistics Royal Military AcademyBrusselsBelgium Centre for Mechanical Technology and Automation Department of Mechanical EngineeringUniversity of AveiroPortugal

The need to develop armour systems to protect against attacks from various sources is increasingly a matter of personal,social and national *** develop innovative armour systems it is necessary to monitor developments being made on the type,technology and performance of the threats(weapons,projectiles,explosives,etc.) Specifically,the use of high protection level helmets on the battlefield is *** development of evaluation methods that can predict injuries and trauma is therefore of major ***,the risk of injuries or trauma that can arise from induced accelerations is an additional *** develop new materials and layouts for helmets it is necessary to study the effects caused by ballistic impacts in the human head on various *** use of numerical simulation is a fundamental tool in this *** work here presented focuses on the use of numerical simulation(finite elements analysis) to predict the consequences of bullet impacts on military helmets on human *** main objectives are to assess the level and probability of head trauma using the Head Injury Criterion,caused by the impact of a 9 mm NATO projectile on a PASGT helmet and to quantify the relevance of projectile plasticity on the whole modelling *** accelerations derived from the impact phenomenon and the deformations caused on the helmet are evaluated using fully three-dimensional models of the helmet,head,neck and *** studies are done at impact angles ranging from 0 to 75°.results are presented and discussed in terms of HIC and probability of acceleration induced trauma *** comparison analyses are done using a rigid and a deformable projectile and it is observed that plastic deformation of the projectile is a significant energy dissipation mechanism in the whole impact process.

关键词： Ballistic impact Helmet impact Plasticity Finite element analysis Injury Trauma HIC

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Seamount chains and hotspot tracks:Superficially similar,deeply different

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Geoscience Frontiers 2023年第6期14卷 307-326页

作者： Edgardo cañón-Tapia División de Ciencias de la Tierra CICESE.Carretera Ensenada-Tijuana#3985Ensenada Baja CaliforniaCP 22860Mexico

Nearly 80%of the seafloor extension has not been covered by high-resolution bathymetry,impeding direct observation of ***,lists of seamount location and height at a global scale have been produced using different *** this work four of such databases(publicly available)are compared with each other to assess their *** identify large differences among databases that could have exerted strong influences on models of seamount production and associated geodynamic *** those differences,it is shown that all databases allow the identification of seamount lines both along the present-day Mid Ocean ridge(MOr)system and on intraplate ***,those seamount lines do not coincide with the so-called hotspot tracks that commonly were defined by selectively focusing attention on the larger *** of all the databases also shows that distinction based only on seamount size between seamounts produced at Mid-Ocean ridge(MOr)environments from those associated with mantle-plum fed-hotspot activity has been ***,combined with the fact that most seamount lines defined by the available databases can be traced back to past locations of MOr indicates that most of the present-day intraplate linear arrays of seamounts,which include some large seamounts,were not produced by the action of underlying mantle anomalies envisaged in the form of mantle *** evidence presented here calls for a reassessment of the form in which volcanic and tectonic activities are conceptually related to each other.

关键词： Seamount origin Chains of seamounts Spatial distribution of volcanism Intraplate volcanism Mid Ocean ridge volcanism

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Effects of Plant residue Decomposition on Soil N Availability,Microbial Biomass and β-Glucosidase Activity During Soil Fertility Improvement in Ghana

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Pedosphere 2019年第5期29卷 608-618页

作者： Samuel T. PArTEY robert B. Z0UGM0rE Naresh V. THEVATHASAN richard F. PrEZIOSI CGI Ar CCAFS West Africa ProgramInternational Crops Research Institute for the Semi-Arid Tropics (ICRISAT)Bamako B.P. Box 320 (Mali) School of Environmental Sciences University of GuelphGuelph NIG 2W1 (Canada) Faculty of Life Sciences The University of ManchesterManchester M13 9PL (UK)

With limited use of inorganic fertilizers on smallholder farms,plant residues could be viable alternatives for soil fertility *** study was conducted to determine how residue quality and decomposition of nine plant species influence soil N availability,microbial biomass,andβ-glucosidase activity during soil fertility *** differences in N concentration were found among the species,ranging from 12.2 g kg-1 in Zea mays to 39.2 g kg-1 in Baphia *** C/N ratio was the highest in ***(34.4),whereas lignin and polyphenol concentrations were the greatest in Acacia *** highest decomposition rate(0.251%per day)occurred in Tithonia diversifolia,and the lowest in ***,Albizia zygia,***,and ***,with the half-lives of 28-56 *** 80%and 89%of N,P,K,ca,and Mg were released from *** in 7 d,compared with over 70%retention in ***,***,and *** decomposition and nutrient release half-lives of Gliricidia sepium,Leucaena leucocephala,Azadirachta indica,and Senna spectabilis were less than 14 *** mineral N,microbial biomass,andβ-glucosidase activity increased under all treatments,with *** having the greatest *** N mineralization occurred in all of the species throughout the experiment,an initial N immobilization was recorded in the ***,***,***,and *** treatments for up to 14 *** and nutrient release rates,mineral N,soil microbial biomass,andβ-glucosidase activity were dependent on residue quality,and P and lignin levels,the lignin/N ratio,and the(lignin+polyphenol)/N ratio had the most significant effects(P≤0.05).

关键词： leguminous species litter quality microbial activity N mineralization nutrient release organic matter

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近代中国大同思想的比较研究及其启示

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安徽史学 2005年第6期 9-13页

作者：操申斌中国人民大学中共党史系北京100872

大同思想是中国传统文化中的瑰宝。中国近代以洪秀全、康有为和孙中山为代表的不同阶级、阶层的先进人士,围绕“中国向何处去”的时代主题,在探索救国救民的征途中,设计了三种各具特色的大同理想方案。它们之间既有联系又有区别,是多种... 详细信息

大同思想是中国传统文化中的瑰宝。中国近代以洪秀全、康有为和孙中山为代表的不同阶级、阶层的先进人士,围绕“中国向何处去”的时代主题,在探索救国救民的征途中,设计了三种各具特色的大同理想方案。它们之间既有联系又有区别,是多种因素综合作用的结果。洪秀全、康有为和孙中山三人大同思想的演进更替过程,具有很强的历史继承性和内在的逻辑性,体现了近代中国乐观主义的时代气质。

关键词：大同民生主义进化论乐观主义

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