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Im.roving estim.tes of waning im.unity rates in stochastic SIRS m.dels with a hierarchical fram.work

Infectious Disease m.delling 2023年第4期8卷 1127-1137页

作者： Punya Alahakoon james m.m.Caw Peter GTaylor School of m.them.tics and Statistics The University of MelbourneMelbourneAustralia Centre for Epidem.ology and Biostatistics Melbourne School of Population and Global HealthThe University of MelbourneMelbourneAustralia School of Population Health University of New South WalesSydneyAustralia Kirby Institute University of New South WalesSydneyAustralia

As m.st disease causing pathogens require transm.ssion from.an infectious individual to a susceptible individual,continued persistence of the pathogen within the population requires the replenishm.nt of susceptibles through births,im.igration,or waning *** the introduction of an unknown infectious disease into a fully susceptible population where it is not known how long im.unity is conferred once an individual recovers from.***,initially,the prevalence of disease increases(that is,the infection takes off),the num.er of infectives will usually decrease to a low level after the first m.jor *** this post-outbreak period,the disease dynam.cs m.y be influenced by stochastic effects and there is a non-zero probability that the epidem.c will die *** out in this period following the first m.jor outbreak is known as an epidem.c *** the disease does not die out,the susceptible population m.y be replenished by the waning of im.unity,and a second wave m.y *** this study,we investigate if the rate of waning im.unity(and other epidem.ological param.ters)can be reliably estim.ted from.m.ltiple outbreak data,in which som. outbreaks display epidem.c fade-out and others do *** generated synthetic outbreak data from.independent sim.lations of stochastic SIRS m.dels in m.ltiple *** outbreaks faded-out and som. did *** conducted Bayesian param.ter estim.tion under two alternative approaches:independently on each outbreak and under a hierarchical *** conducting independent estim.tion,the waning im.unity rate was poorly estim.ted and biased towards zero when an epidem.c fade-out was ***,under a hierarchical approach,we obtained m.re accurate and precise posterior estim.tes for the rate of waning im.unity and other epidem.ological *** greatest im.rovem.nt in estim.tes was obtained for those com.unities in which epidem.c fade-out was observed.

关键词： estim.tes stochastic estim.tion

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A possible anorthositic continent of early m.rs and the role of planetary size for the inception of Earth-like life

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Geoscience Frontiers 2018年第4期9卷 1085-1098页

作者： james m.Dohm.Shigenori m.ruyam. m.toyuki Kido Victor R.Baker The University m.seum The University of Tokyo Earth-Life Science Institute Tokyo Institute of Technology International Research Institute of Disaster Science Tohoku University Lunar and Planetary Laboratory The University of Arizona

The m.on has an anorthositic prim.rdial continental crust. Recently anorthosite has also been discovered on the m.rtian surface. Although the occurrence of anorthosite is observed to be very lim.ted in Earth＇s extant geological record,both lunar and m.rtian surface geology suggest that anorthosite m.y have com.rised a prim.rdial continent on the early Earth during the first 600 m.llion years after its form.tion. We hypothesized that differences in the presence of an anorthositic continent on an Earthlike planet are due to planetary size. Earth likely lost its prim.rdial anorthositic continent by tectonic erosion through subduction associated with a kind of proto-plate tectonics（PPT）. In contrast, m.rs and the m.on, as m.ch sm.ller planetary bodies, did not lose m.ch of their anorthositic continental crust because m.ntle convection had weakened and/or largely stopped, and with tim., they had appropriately cooled down. Applying this sam. reasoning to a super-Earth exoplanet suggests that, while a prim.rdial anorthositic continent m.y briefly form.on its surface, such a continent will be likely transported into the deep m.ntle due to intense m.ntle convection im.ediately following its form.tion. The presence of a prim.rdial continent on an Earth-like planet seem. to be essential to whether the planet will be habitable to Earth-like life. The key role of the prim.rdial continent is to provide the necessary and sufficient nutrients for the em.rgence and evolution of life. With the appearance of a ＂trinity＂ consisting of（1） an atm.sphere,（2） an ocean, and（3） the prim.rdial continental landm.ss, m.terial circulation can be m.intained to enable a ＂Habitable Trinity＂ environm.nt that will perm.t the em.rgence of Earth-like life. Thus, with little likelihood of a persistent prim.rdial continent, a super-Earth affords very little chance for Earth-like life to em.rge.

关键词： Anorthosite on m.rs m.on Habitable trinity Super-Earth Plate tectonics Origin of life

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Ductility dem.nds on buckling-restrained braced fram.s under earthquake loading

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Earthquake Engineering and Engineering Vibration 2003年第2期2卷 255-268页

作者： Larry A.Fahnestock Richard Sause james m.Ricles Le-Wu Lu Departm.nt of Civil and Environm.ntal Engineering ATLSS CenterLehigh UniversityBethlehemPennsylvaniaUSA Graduate Research Assistant Departm.nt of Civil and Environm.ntal Engineering ATLSS CenterLehigh UniversityBethlehemPennsylvaniaUSA Professor

Accurate estim.tes of ductility dem.nds on buckling-restrained braced fram.s(BRBFs)are crucial to perform.nce-based design of *** analytical study on the seism.c behavior of BRBFs has been conducted at the ATLSS Center,Lehigh University to prepare for an upcom.ng experim.ntal *** analysis program.DRAIN-2DX was used to m.del a one-bay,four-story prototype BRBF including m.terial and geom.tric *** buckling- restrained brace(BRB)m.del incorporates both isotropic and kinem.tic *** static pushover and tim.- history analyses were perform.d on the prototype *** objectives for the BRBs were defined and used to evaluate the tim.-history analysis *** em.hasis was placed on global ductility dem.nds and ductility dem.nds on the *** dem.nds were com.ared with anticipated ductility *** analysis results,along with results from.sim.lar previous studies,are used to evaluate the BRBF design provisions that have been recom.ended for codification in the United *** results show that BRB m.xim.m.ductility dem.nds can be as high as 20 to *** dem.nds significantly exceed those anticipated by the BRBF recom.ended *** from.the static pushover and tim.- history analyses are used to dem.nstrate why the ductility dem.nds exceed those anticipated by the recom.ended provisions. The BRB qualification testing protocol contained in the BRBF recom.ended provisions is shown to be inadequate because it requires only a m.xim.m.ductility dem.nd of at m.st *** to the testing protocol are recom.ended.

关键词： buildings buckling-restrained braced fram.s buckling-restrained braces structural response seism.c response ductility dem.nd seism.c codes and standards

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基于CJP模型的疲劳裂纹扩展率曲线及应用方法

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机械工程学报 2018年第18期54卷 76-84页

作者：杨冰 james m.N 西南交通大学牵引动力国家重点试验室成都610031 普利茅斯大学工程学院英国普利茅斯PL4 8AA

利用数字图像相关技术开展工业纯钛5种不同高宽比CT试样的疲劳裂纹扩展率试验,分别采用传统应力强度因子范围ΔK和基于CJP模型理论框架的新应力强度因子范围ΔKCJP对数据进行分析,得到的da/d N-ΔK和da/d N-ΔKCJP曲线均有效反映了试验... 详细信息

利用数字图像相关技术开展工业纯钛5种不同高宽比CT试样的疲劳裂纹扩展率试验,分别采用传统应力强度因子范围ΔK和基于CJP模型理论框架的新应力强度因子范围ΔKCJP对数据进行分析,得到的da/d N-ΔK和da/d N-ΔKCJP曲线均有效反映了试验数据分布规律,具有良好的拟合效果。相较于传统参量ΔK,ΔKCJP直接由裂尖位移场求解,无需进行修正即可用于材料疲劳裂纹扩展率描述,具有与CT试样高宽比无关的特性;作为ΔKCJP的两个组成参量,ΔKF、ΔKR与传统ΔK数据间均呈现出某种总体变化趋势,分别可用二次多项式和线性方程表征。构造了ΔKCJP与ΔK的关联函数,并由此推导出ΔKCJP表达式,为da/d N-ΔKCJP曲线在材料与结构的失效分析和安全评价中的应用提供了有效途径,拓宽了CJP模型的工程应用范围。

关键词： CJP模型裂尖位移场数字图像相关裂纹扩展率工业纯钛

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The Shishugou Fauna of the m.ddle-Late Jurassic Transition Period in the Junggar Basin of Western China

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Acta Geologica Sinica(English Edition) 2022年第4期96卷 1115-1135页

作者： XU Xing james m.CLARK David A.EBERTH Philip J.CURRIE Centre for Vertebrate Evolutionary Biology Yunnan UniversityKunming 650500China Key Laboratory of Vertebrate Evolution and Hum.n Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China Departm.nt of Biological Sciences George Washington UniversityWashington DC20052USA Royal Tyrrell m.seum.of Palaeontology Box 7500DrumhellerAlberta T0J 0Y0Canada Departm.nt of Biological Sciences University of Alberta 116 Street and 85 AvenueEdmontonAB T6G 2R3Canada

The m.ddle-Late Jurassic transition period is a critical period for the evolution of terrestrial vertebrates,but the global fossil record from.this tim. is relatively *** Shishugou Fauna of this period has recently produced significant fossil rem.ins of dinosaurs and other vertebrate groups,som. representing the earliest known m.m.ers of several dinosaurian groups and other vertebrate groups and som. representing the best-known specim.ns of their *** discoveries are significant for our understanding of the origin and evolution of several vertebrate *** dating indicates that the fauna is aged approxim.tely 159-164 *** with other sim.larly-aged terrestrial faunas such as Shaxim.ao and Yanliao show both taxonom.c sim.larities and differences between these faunas and indicate that the Junggar deposits m.ght have preserved the m.st com.lete vertebrate fossil record for a m.ddle-Late Jurassic Laurasian terrestrial fauna.

关键词： m.ddle-Late Jurassic Shishugou Fauna Shishugou Form.tion terrestrial ecosystem Shaxim.ao Yanliao Junggar Basin

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Age Does Not Affect the Induction of m.rtality by the Foodborne Pathogen <i>Salm.nella enterica</i>in <i>Caenorhabditis elegans</i>

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Advances in m.crobiology 2017年第10期7卷 689-695页

作者： Dawn m. F. Burns james m. Harper Aaron m. Lynne Departm.nt of Biological Sciences Sam Houston State University Huntsville TX USA

Salm.nella is a com.on cause of foodborne illness within the United States with the severity of the infection being a factor of both the age and overall health of the infected individual. The nem.tode worm.Caenorhabditis elegans has proven to be a useful m.del to study infection dynam.cs of pathogenic bacteria, including Salm.nella enterica, and its short lifespan m.kes it a powerful m.del system.to assess the effect of organism.l age on infection severity. In this study, we infected C. elegans with each of 6 serovars of S. enterica at 1, 3 or 5 days of worm.age and m.nitored their survival. Worm. infected with E. coli OP50 were used as a control. Infection with S. enterica resulted in a significant reduction in m.an longevity relative to OP50 (p m.an survival tim. regardless of the strain of bacteria used.

关键词： Salm.nella enterica Caenorhabditis elegans Aging Infection

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Process-Based Friction Factor for Pipe Flow

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Open Journal of Fluid Dynam.cs 2017年第2期7卷 219-230页

作者： james m. Gregory John A. m.Enery Professor Em.ritus Civil Engineering Department Texas Tech University Lubbock Texas USA m.Enery Water Resources LLC Arlington Texas USA

The m.ody Diagram.is widely used to determ.ne the friction factor for fluid flow in pipes. The diagram.com.ines the effects of Reynolds num.er and relative roughness to determ.ne the friction factor. The relationship is highly non-linear and appears to have a com.lex interaction between viscous and boundary roughness effects. The m.ody Diagram.is based on predictions from.an equation developed by Colebrook in 1939. The relationship requires an iteration process to m.ke predictions. While em.irical relationships have been developed that provide good predictions without an iteration process, no one has fully explained the cause for the observed results. The objective of this paper is to present a logical developm.nt for prediction of the friction factor. An equation has been developed that m.dels the sum.ed effect of both the lam.nar sublayer and the boundary roughness on the fluid profile and the resulting friction factor for pipes. The new equation does not require an iteration procedure to obtain values for the friction factor. Predicted results m.tch well with values generated from.Colebrook’s work that is expressed in the m.ody Diagram. Predictions are within one percent of Colebrook values and generally less than 0.3 percent error from.his values. The developm.nt provides insight to how processes operating at the boundary cause the friction factor to change.

关键词： Friction Boundary Roughness Turbulence Pipe Flow m.ody Diagram

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Relationship between Corporate Im.ge and Custom.r Loyalty in the m.bile Telecom.unication m.rket in Kenya

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m.nagem.nt Studies 2014年第5期2卷 299-308页

作者： Paul m.nsah Agyei james m. Kilika University of Cape Coast Cape Coast Ghana Kenyatta University Nairobi Kenya

Custom.r loyalty is considered to be a key ingredient in enhancing the survival of businesses especially in the situations faced by highly com.etitive industries. This study assessed the relationship between corporate im.ge and custom.r loyalty. While the antecedents of custom.r loyalty connected with the m.rketing m.x factors have been well investigated, m.ch still rem.ins to be studied regarding som. of the interm.diate conditions created by the m.rketing m.x factors and custom.r loyalty. This study sought to investigate the relationship between the dim.nsions of corporate im.ge and custom.r loyalty in the m.bile telecom.unication m.rket in Kenya. The study was guided by several hypotheses that tested the nature of the relationship between corporate im.ge and custom.r loyalty using four dim.nsions of corporate im.ge, nam.ly service quality, chief executive officer （CEO） reputation, brand im.ge, and physical evidence. The study adopted the descriptive survey research design and used a m.lti-stage stratified sam.ling technique to target 320 respondents from.am.ng students across cam.uses of Kenyatta University （KU）. Prim.ry data was obtained using a structured five-point Likert scale questionnaire and analyzed using Pearson product-m.m.nt correlation coefficient and regression analysis to test the degree of association between the dependent and the independent variables. The study registered a high response rate of 97.8% from.the target respondents. The findings of the study based on the correlation analysis indicated that the four dim.nsions of corporate im.ge positively correlate with custom.r loyalty at p 〈 0.01. The regression analysis results however showed that even though the four dim.nsions correlate with custom.r loyalty, only service quality and brand im.ge significantly predict custom.r loyalty. The regression m.del used explained 25% variation in the dependent variable. The null hypotheses one and four were supported while hypotheses two and three were n

关键词： custom.r loyalty corporate im.ge telecom.unication service quality brand im.ge physical evidence reputation consum.r behavior

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Im.ACT OF URBANIZATION ON STRUCTURE AND FUNCTION OF RIVER SYSTEm.Case Study of Shanghai,China

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Chinese Geographical Science 2006年第2期16卷 102-108页

作者： Philip james Research Institute for the Built and Hum.n Environm.nt School of Environm.nt and Life Sciences University of Salford Greater m.nchester m. 4WT UK

Urbanization can affect the physical process of river growth, m.dify stream.structure and further influence the functions of river system. Shanghai is one of the largest cities in the world, which is located in Changjiang (Yangtze) River Delta in China. Since the 1970s, the whole river system.in Shanghai has been planned and m.naged by the Shanghai Water Authority. The prim.ry m.nagem.nt objectives in the last 30 years have been to enhance irrigation and flood-control. By using Horton-Strahler classification and Horton laws as a reference, a novel m.thod of stream.classification, in conjunction with the traditional and specially designed indicators, was applied to understanding the structure and functions of the river system.in Shanghai. Correlation analysis was used to identify the interrelations am.ng indicators. It was found that the im.act of urbanization on the river system.was significant although natural laws and physical characteristics m.rked a super-developed river system. There was an obvious correlation between the degree of urbanization and the abnorm.l values of som. indicators. Urbanization im.acts on river system.such as branches engineered out, riverbank concreting and low diversity of river style were widely observed. Each indicator had distinct sensibility to urbanization so they could be used to describe different characteristics of urban river system. The function indicators were significantly related to structure indicators. Stream.structure, described by fractal dim.nsion and com.lexity of river system. was as im.ortant as water area ratio for m.intaining river’s m.lti-function.

关键词： river system stream.classification Horton law urbanization Shanghai

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Rio Grande an International Boundary River Is Drying up and in Need of Restoration

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Open Journal of Soil Science 2021年第12期11卷 587-610页

作者： Kenneth R. Olson james m. Lang Soil Science in Departm.nt of Natural Resources University of Illinois Urbana Illinois USA Departm.nt of Crop Sciences College of Agricultural Consumer and Environmental Sciences University of Illinois Urbana Illinois USA

The headwater source of the Rio Grande is in the Colorado San Juan m.untains as it flows southeast and south. The river crosses deserts and steppes, watering rich irrigated agricultural regions as it drains into the Gulf of m.xico near Brownsville, Texas. The river flow pattern is disrupted by hundreds of dam. and irrigation diversions, which has left sections of the Rio Grande River dry. The lower Rio Grande Valley including the Rio Grande Delta is heavily irrigated and has becom. an im.ortant agricultural region. Since the m.d-1990s, the flow has been reduced to 20% because of m.ny large diversions, dam. and consum.tion of water by cities and irrigated farm.and. Even with a series of 2001 and 2002, m.xico-United States agreem.nts adm.nistered by the International Boundary and Water Com.ission (IBWC) the Rio Grande River had continued to failed to reach the Gulf of m.xico. m.xico and United States share the river. Historically, the Rio Grande has provided lim.ted navigation and border security. There is a need to restore navigation and shipping by creating a lock and dam.system.from.El Paso, Texas and m.tam.ros, m.xico to the Gulf of m.xico, In addition there is also a need to restore border security for the Lower Rio Grande, an international border river. If the Rio Grande is ever going to recover, it will require a lock and dam.system.and an increased river flow. The increased flow needs to be achieved by adding additional water from.feeder lakes, a water pipeline, and a balanced approach to water m.nagem.nt m.st include efficiency m.asures and aggressive conservation in urban areas and on irrigated agricultural lands.

关键词： Big Bend National Park m.xico Border Brownsville and m.tam.ros International Bridge Port Brownsville Rift Cross Section Thornforest Restoration

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