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On solitary *** 2 A unified perturbation theory for higher-order waves

Acta Mechanica sinica 2005年第6期21卷 515-530页

作者： theodore Yaotsu Wu Xinlong Wang Wendong Qu California Institute of Technology Pasadena CA 91125 U.S.A. Fellow Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China state Key Laboratory of Modern Acoustics and Institute of Acoustics Nanjing University Nanjing 210093 China California Institute of Technology Pasadena CA 91125 U.S.A PIMCO Newport Beach CA 92660 U.S.A.

A unified perturbation theory is developed here for calculating solitary waves of all heights by series expansion of base flow variables in powers of a small base parameter to eighteenth order for the one-parameter family of solutions in exact form, with all the coefficients determined in rational numbers. Comparative studies are pursued to investigate the effects due to changes of base parameters on （i） the accuracy of the theoretically predicted wave properties and （ii） the rate of convergence of perturbation expansion. Two important results are found by comparisons between the theoretical predictions based on a set of parameters separately adopted for expansion in turn. First, the accuracy and the convergence of the perturbation expansions, appraised versus the exact solution provided by an earlier paper [1] as the standard reference, are found to depend, quite sensitively, on changes in base parameter. The resulting variations in the solution are physically displayed in various wave properties with differences found dependent on which property （e.g. the wave amplitude, speed, its profile, excess mass, momentum, and energy）, on what range in value of the base, and on the rank of the order n in the expansion being addressed. secondly, regarding convergence, the present perturbation series is found definitely asymptotic in nature, with the relative error δ （n）（the relative mean-square difference between successive orders n of wave elevations） reaching a minimum, δm at a specific order, n = n both depending on the base adopted, e.g. nm,α= 11-12 based on parameter α （wave amplitude）, nm,δ = 15 on δ （amplitude-speed square ratio）, and nm.ε= 17 on ε （ wave number squared）. The asymptotic range is brought to completion by the highest order of n = 18 reached in this work.

关键词： solitary waves on water Unified perturbation theory Base functions Base parameters Asymptotic representation

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Hierarchically structured Nanocomposites via a“systems Materials science”Approach

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Accounts of Materials Research 2022年第12期3卷 1248-1259页

作者： Rebecca L.Li Carl J.Thrasher theodore Hueckel Robert J.Macfarlane Department of Materials science and Engineering Massachusetts Institute of TechnologyCambridgeMassachusetts 02139United States Department of Mechanical Engineering Massachusetts Institute of TechnologyCambridgeMassachusetts 02139United States

CONsPECTUs:Nanocomposite materials can achieve desirable characteristics otherwise unavailable to single component systems,making them attractive platforms to precisely modulate a material’s mechanical,electromagnetic,thermal,and optical *** these properties are often dependent on the organization of constituent materials just as much as their relative composition,intentionally programming composite properties requires hierarchical structural control across many length ***,the fundamental forces governing the atomic,molecular,nanoscale,microscale,and macroscale composition and structure of a material are all interlinked,and thus must be manipulated simultaneously to properly create ideal designer materials.

关键词： properties composite composites

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Determinants of inspiratory muscle function in healthy children

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Journal of sport and Health science 2019年第2期8卷 183-188页

作者： theodore Dassios Gabriel Dimitriou Department of Child Health King's College Hospital Department of Paediatrics University of Patras Medical School

Background: Children are affected by disorders that have an impact on the respiratory muscles. Inspiratory muscle function can be assessed by means of the noninvasive tension–time index of the inspiratory muscles(TTImus). Our objectives were to identify the determinants of TTImus in healthy children and to report normal values of TTImus in this ***: We measured weight, height, upper arm muscle area(UAMA), and TTImusin 96 children aged 6–18 years. The level and frequency of aerobic activity was assessed by ***: TTImuswas significantly lower in male subjects(0.095 ± 0.038, mean ± sD) compared with female subjects(0.126 ± 0.056)(p = 0.002).TTImus was significantly lower in regularly exercising(0.093 ± 0.040) compared with nonexercising subjects(0.130 ± 0.053)(p s was significantly negatively related to age(r =-0.239, p = 0.019), weight(r =-0.214, p = 0.037), height(r =-0.355, p stic regression analysis revealed that height and aerobic exercise were significantly related to TTImus independently of age, weight, and UAMA. The predictive regression equation for TTImus in male subjects was TTImus = 0.228-0.001 × height(cm), and in female subjects it was TTImus = 0.320-0.001 × height(cm).Conclusion: Gender, age, anthropometry, skeletal muscularity, and aerobic exercise are significantly associated with indices of inspiratory muscle function in children. Normal values of TTImus in healthy children are reported.

关键词： Aerobic exercise Children Inspiratory muscle function Maximal inspiratory pressure skeletal muscle function Tension-time index of the inspiratory muscles

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Helicobacter pylori,gastric microbiota and gastric cancer relationship:Unrolling the tangle

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World Journal of Gastrointestinal Oncology 2022年第5期14卷 959-972页

作者： Christos Liatsos Apostolis Papaefthymiou Nikolaos Kyriakos Michail Galanopoulos Michael Doulberis Marios Giakoumis Evangelia Petridou Christos Mavrogiannis theodore Rokkas Jannis Kountouras Department of Gastroenterology 401 General Military Hospital of AthensAthens 11525Greece Gastroenterology University Hospital of LarissaLarissa 41336Greece Division of Gastroenterology and Hepatology Medical University DepartmentKantonsspital AarauAarau 1234Switzerland Department of Microbiology “Agia Sofia”Paediatric HospitalGoudiAthens 11527Greece Gastrointestinal and Liver Unit Faculty of NursingKifissia General and Oncology HospitalKaliftakiN.Kifisia 14564Greece Gastroenterological Clinic Henry Dunant HospitalAthens 11525Greece Department of Internal Medicine Second Medical ClinicIppokration HospitalAristotle University of ThessalonikiThessaloniki 41336MacedoniaGreece

Helicobacter pylori infection(Hp-I)represents a typical microbial agent intervening in the complex mechanisms of gastric homeostasis by disturbing the balance between the host gastric microbiota and mucosa-related factors,leading to inflammatory changes,dysbiosis and eventually gastric *** normal gastric microbiota shows diversity,with Proteobacteria[Helicobacter pylori(***)belongs to this family],Firmicutes,Actinobacteria,Bacteroides and Fusobacteria being the most abundant *** studies indicate that *** has inhibitory effects on the colonization of other bacteria,harboring a lower diversity of them in the *** comparing the healthy with the diseased stomach,there is a change in the composition of the gastric microbiome with increasing abundance of ***(where present)in the gastritis stage,while as the gastric carcinogenesis cascade progresses to gastric cancer,the oral and intestinal-type pathogenic microbial strains ***-I creates a premalignant environment of atrophy and intestinal metaplasia and the subsequent alteration in gastric microbiota seems to play a crucial role in gastric tumorigenesis *** *** eradication is suggested to restore gastric microbiota,at least in primary *** is more than clear that Hp-I,gastric microbiota and gastric cancer constitute a challenging tangle and the strong interaction between them makes it difficult to *** studies are considered of crucial importance to test the complex interaction on the modulation of the gastric microbiota by *** as well as on the relationships between the gastric microbiota and gastric carcinogenesis.

关键词： Helicobacter pylori infection Gastric microbiota Gastric cancer Oncogenesis Dysbiosis Helicobacter pylori eradication

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A review: Challenges and opportunities for artificial intelligence and robotics in the offshore wind sector

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能源与人工智能(英文) 2022年第2期8卷 177-212页

作者： Daniel Mitchell Jamie Blanche sam Harper theodore Lim Ranjeetkumar Gupta Osama Zaki Wenshuo Tang Valentin Robu simon Watson David Flynn smart systems Group Institute of SensorsSignals and SystemsSchool of Engineering and Physical SciencesHeriot-Watt UniversityEdinburghEH144ASUnited Kingdom Centre for Mathematics and Computer science Intelligent and Autonomous Systems GroupCWIAmsterdam1098 XG Netherlands Algorithms Group Faculty of Electrical EngineeringMathematics and Computer Science(EEMCS)Delft University of Technology(TU Delft)Delft2628 XE Netherlands The University of Manchester Department of Electrical and Electronic EngineeringOxford RoadManchesterM139PL United Kingdom James Watt school of Engineering University of GlasgowG128QQUnited Kingdom

The UK has set plans to increase offshore wind capacity from 22GW to 154GW by 2030. With such tremendous growth, the sector is now looking to Robotics and Artificial Intelligence (RAI) in order to tackle lifecycle service barriers as to support sustainable and profitable offshore wind energy production. Today, RAI applications are predominately being used to support short term objectives in operation and maintenance. However, moving forward, RAI has the potential to play a critical role throughout the full lifecycle of offshore wind infrastructure, from surveying, planning, design, logistics, operational support, training and decommissioning. This paper presents one of the first systematic reviews of RAI for the offshore renewable energy sector. The state-of-the-art in RAI is analyzed with respect to offshore energy requirements, from both industry and academia, in terms of current and future requirements. Our review also includes a detailed evaluation of investment, regulation and skills development required to support the adoption of RAI. The key trends identified through a detailed analysis of patent and academic publication databases provide insights to barriers such as certification of autonomous platforms for safety compliance and reliability, the need for digital architectures for scalability in autonomous fleets, adaptive mission planning for resilient resident operations and optimization of human machine interaction for trusted partnerships between people and autonomous assistants. Our study concludes with identification of technological priorities and outlines their integration into a new ‘symbiotic digital architecture’ to deliver the future of offshore wind farm lifecycle management.

关键词： Artificial intelligence Autonomous systems Digitalization Offshore renewable energy Offshore wind farms Robotics

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Comparative multi-locus assessment of modern Asian newts(Cynops, Paramesotriton, and Pachytriton:salamandridae) in southern China suggests a shared biogeographic history

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Zoological Research 2022年第5期43卷 706-718页

作者： Zhi-Yong Yuan Yun-Ke Wu Fang Yan Robert W.Murphy theodore J.Papenfuss David B.Wake Ya-Ping Zhang Jing Che state Key Laboratory of Genetic Resources and Evolution&Yunnan Key Laboratory of Biodiversity and Ecological security of Gaoligong Mountain Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan 650223China Key Laboratory of Freshwater Fish Reproduction and Development(Ministry of Education) School of Life SciencesSouthwest UniversityChongqing 400715China Department of Ecology and Evolutionary Biology Cornell UniversityIthaca 14850USA College of Life science Yunnan UniversityKunmingYunnan 650091China Centre for Biodiversity and Conservation Biology Royal Ontario MuseumTorontoOntario M5S 2C6Canada Museum of Vertebrate Zoology University of CaliforniaBerkeleyCA 94720USA

Evolutionary biologists are always interested in deciphering the geographic context of diversification,therefore they introduced the concept of comparative phylogeography, which helps to identify common mechanisms that contribute to shared genetic structures among organisms from the same ***, we used multi-locus genetic data along with environmental data to investigate shared phylogeographic patterns among three Asianendemic newt genera, Cynops, Paramesotriton and Pachytriton, which occurred in montane/submontane streams or ponds in southern China. Our 222samples from 78 localities covered the entire range of the three genera and represented the largest dataset of this group to date. We reconstructed matrilineal genealogies from two protein-coding,mitochondrial genes, and gene network from two nuclear genes. We also estimated divergence times of major cladogenetic events and used occurrence data to evaluate niche difference and similarity between lineages. Our results revealed a common basal split in all three genera that corresponds to the separation of two geographic terrains of southern *** ancient divergence occurred during middle to late Miocene and likely correlate with paleoclimatic fluctuations caused by the uplift of the Qinghai-Xizang (Tibet) Plateau (QTP).Particularly,the strengthening and weakening of Asian summer monsoons during the Miocene may have profoundly impacted southern China and led to repeatedly vicariance in those ***,despite differences in realized niches between lineages,there is no evidence for divergence of fundamental *** of old newt matriline lineages in mountains of southern China suggests that the region acts as both museums and cradles of *** on those results,we advocate a multi-pronged protection strategy for newts in the three genera.

关键词： Amphibian Comparative phylogeography Qinghai-Xizang(Tibet)Plateau East Asian monsoons Ecological niche modeling species museums and cradles

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Influence of the Age of Bamboo Culm and Its Vertical Position on the Technological Properties of Bamboo Fibers: A Case of Bambusa vulgaris species from Cameroonian Culture

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Open Journal of Composite Materials 2022年第3期12卷 98-110页

作者： Joseph Loic souck theodore Tchotang Bienvenu Kenmeugne Laboratory of Civil and Mechanical Engineering National Advanced School of Engineering Yaoundé 1 University Yaoundé Cameroon

Due to their interesting properties, bamboo fibers are more and more used as reinforcements in polymer matrices as a substitute for synthetic fibers. For their future service life, it is important to understand their physical and mechanical behavior over time in order to control the aging phenomenon within this fiber. The paper analyzed the influence of the age of the bamboo thatch and the vertical position of the Bambusa vulgaris species cultivated in Cameroon on the physicomechanical properties of the fibers extracted from the thatch. Fibers were mechanically extracted from three bamboo culms aged respectively 3 years (BV3), 4 years (BV4) and 5 years (BV5). The culms were thus identified according to their number of ramifications, and were felled no abated for a total of three culms. A section of about one meter on each of the parts (lower part, middle part, upper part) of these three culms was made for the opposite technological studies. Each age was therefore represented by three portions of thatch, one from the upper part, one from the middle part and the last from the lower part of the thatch, all giving a total number of nine samples taken and marked BV3inf, BV3moy, BV3sup, BV4inf, BV4moy, BV4sup, BV5inf, BV5moy, BV5sup before handling in the laboratory. Physical (density, moisture absorption rate) and mechanical (tensile tests according to DIN EN IsO 13934-1, natural durability) characterizations were used to better understand the mechanisms of this influence. In view of all the results obtained, the fiber from the upper part of the 3-year-old thatch (BV3sup) is the one with the best characteristics and is recommended for a better elaboration of bamboo fiber composites: (Density: 0.83;Absorption rate 11.7%;Young’s modulus: 7.4 GPa;Maximal stress: 64.3 MPa;Elongation at rupture: 1.1;Loss of mass natural durability: 7.63%).

关键词： Fiber Bamboo Culm Characterization Elaboration Extraction

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Analysis of charge density and Fermi level of Al In sb/In sb single-gate high electron mobility transistor

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Journal of semiconductors 2015年第6期36卷 47-52页

作者： s.theodore Chandra N.B.Balamurugan M.Bhuvaneswari N.Anbuselvan N.Mohankumar National Instruments Electronics Laboratory Department of ECE Thiagarajar College of Engineering Department of ECE SKP Engineering College

A compact model is proposed to derive the charge density of the AlInsb/Insb HEMT devices by con- sidering the variation of Fermi level, the first subband, the second subband and sheet carrier charge density with applied gate voltage. The proposed model considers the Fermi level dependence of charge density and vice versa. The analytical results generated by the proposed model are compared and they agree well with the experimental results. The developed model can be used to implement a physics based compact model for an Insb HEMT device in sPICE applications.

关键词： charge density Fermi level high electron mobility transistor 2D analytical model

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Deposition of Nutrients From Harmattan Dust in Ghana, West Africa

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Pedosphere 2015年第4期25卷 613-621页

作者： Henrik BREUNING-MadsEN theodore Wola AWadZI Gry LYNGsIE Institute of Geosciences and Natural Resource Management University of Copenhagen Department of Geography and Resource Development University of Ghana

In order to measure dust's nutrient input on farmland in different agro-ecological zones, Harmattan dust was sampled by mats with plastic straw in Ghana between 2002–2006. The inputs of total nutrients by Harmattan dust in Ghana per Harmattan period were about 1–2 kg Ca ha-1, 0.5–2 kg K ha-1, 0.5–1.5 kg Mg ha-1and less than 0.5 kg P ha-1. Compared with the annual input of nutrients by precipitation, the dust accounted for 10% or less of Ca, Mg and K but approximately 20%–40% of P. The input of nutrients by dust was only valid for areas with vegetation, because in areas with none or sparse vegetation, loss of soil due to wind erosion and hereby loss of nutrients might be significant. In farmland areas with bare and vegetated fields there seemed to be an internal redistribution of the nutrients and not a net gain of nutrients from outside the area(long-range transported dust). The input of P by dust might be of some importance in the traditional shifting cultivation systems, while the inputs of other three nutrients of Ca, Mg and K were so low that they must be considered insignificant. In the intensive agriculture systems with huge inputs of manures and fertilizers the nutrient input by dust is insignificant and could be neglected.

关键词：养分输入加纳营养物质沉积西非稀疏植被养分投入农业生态区

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Interaction of genotype and environment effects on important traits of cassava(Manihot esculenta Crantz)

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The Crop Journal 2017年第5期5卷 373-386页

作者： Athanase Nduwumuremyi Rob Melis Paul shanahan Asiimwe theodore University of KwaZulu-Natal African Center for Crop Improvement (ACCI) Rwanda Agriculture Board (RAB)

General and specific environmental adaptation of genotypes is the main goal of ***, genotype-by-environment(G x E) interaction complicates the identification of genotypes for release. This study aimed at analyzing the effects of G x E interaction on the expression of important cassava traits using two multivariate analyses: additive main effects and multiplicative interaction(AMMI) and genotype stability index(GsI). Total carotene content(TCC), postharvest physiological deterioration(PPD), and reaction to viral diseases were significantly affected by G x E interaction effects. The low percent(%)variation due to genotype for cassava brown streak disease(GBsD) explained the influence of environment on CBsD expression. The % variation due to genotype for TCC was higher(96%) than variation due to environment(1.7%) and G x E interaction(2.4%) indicating a low interaction effect of environment on TCC accumulation. The % variation due to genotype was higher than % variation due to environment for all traits but CBsD root necrosis and CBsD on stems, indicating the influence of environment on the severity of the viral diseases. These findings indicate that screening for disease resistance requires multi-environment trials, whereas a single-environment trial suffices to screen for total carotene content.

关键词： additive main effects and multiplicative interaction Genotype adaptation Genotype stability index Physiological postharvest deterioration Total carotene content

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