Dissertations / Theses on the topic 'Species displacement'
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 25 dissertations / theses for your research on the topic 'Species displacement.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
Short, Kristen. "Population genetic structure and species displacement during range expansion of invasive geckos." University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1289840091.
Full textDAME, ELIZABETH. "BEHAVIORAL MECHANISMS OF INVASION AND DISPLACEMENT IN PACIFIC ISLAND GECKOS." University of Cincinnati / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1100810530.
Full textReifova, Radka, Jiri Reif, Marcin Antczak, and Michael Nachman. "Ecological character displacement in the face of gene flow: Evidence from two species of nightingales." BioMed Central, 2011. http://hdl.handle.net/10150/610382.
Full textRowland, Lindsey Claire. "Relationship of Reproductive Timing and Climate Change to the Displacement of Peromyscus maniculatus gracilis by Peromyscus leucopus noveboracensis." Miami University / OhioLINK, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=miami1055963515.
Full textMateus, Pedro Miguel Veríssimo. "Ditopic molecular architectures for the recognition of anionic species." Doctoral thesis, Universidade Nova de Lisboa. Instituto de Tecnologia Química e Biológica, 2011. http://hdl.handle.net/10362/6859.
Full textAnions are ubiquitous and very important species in biological, medicinal, industrial and environmental processes. In biology, anions are essential for normal metabolic functions, where their specific recognition, transport and detection play a very important role. On the other hand, the uncontrolled release of anions into the environment poses a significant threat. The development of synthetic receptors capable of sequestering anions should, therefore, provide solutions to a number of problems of current interest. To be suitable for real-life applications, as for instance the detection and quantification of biologically active anions in clinical laboratories or the environmental monitoring and/or removal of pollutants, synthetic receptors need to be able to function in aqueous solution. However, due to the high dielectric constant and good hydrogen bond donor and acceptor capabilities, water is the most challenging medium for anion recognition.(...)
The work described in this thesis was entirely carried out in Instituto de Tecnologia Química e Biológica, Oeiras, Portugal. Pedro Mateus has received financial support from Fundação para a Ciência e Tecnologia, ref. SFRH/BD/36159/2007.
Klayman, Benjamin Joseph. "A quantitative description at multiple scales of observation of accumulation and displacement patterns in single and dual-species biofilms." Diss., Montana State University, 2007. http://etd.lib.montana.edu/etd/2007/klayman/KlaymanB0807.pdf.
Full textComes, Navarro María. "Hybrid inorganic-organic materials for the optical recognition of neutral and anionic species." Doctoral thesis, Universitat Politècnica de València, 2016. http://hdl.handle.net/10251/62153.
Full text[ES] La tesis doctoral que se presenta bajo el título "Hybrid inorganic-organic materials for the optical recognition of neutral and anionic species" ha tenido como objetivo principal la síntesis y caracterización de materiales híbridos orgánico-inorgànicos basados en la combinación de los principios de la Química Supramolecular y la Ciencia de los Materiales. Recientes estudios corroboran que la cooperación entre estas dos áreas de la Química permite simular lo que ya hace millones de años realizan de forma natural los organismos vivos. A nivel celular, muchas de las funciones vitales están relacionadas con la habilidad de un receptor concreto para reconocer una determinada especie, dando una respuesta específica. Pero lo que resulta más interesante, es que en los organismos vivos, la mayoría de estos sistemas no existen en forma de moléculas disueltas, sino que están unidos con mayor o menor flexibilidad a un esqueleto bio(in)orgánico. Cuando imitamos estos sistemas teniendo en cuenta la química supramolecular y analítica, nos encontramos que necesitamos de una molécula indicadora que sea capaz de unirse a la especie que queremos detectar y que a su vez, esta unión produzca un cambio en las propiedades físico-químicas de la entidad para producir una señal. Pero además, si aprovechamos el hecho de que los materiales silíceos nanoestructurados presentan una alta estabilidad física y química y que proporcionan cavidades donde alojar al sistema sensor, tenemos la combinación híbrida orgánico-inorgánico sintética similar a la natural. Con el objetivo de desarrollar esta idea, hemos utilizado sistemas sensores ampliamente estudiados en procedimientos de reconocimiento molecular en disolución acuosa y los hemos aplicado a los materiales híbridos orgánico-inorgànicos. De esta manera, el trabajo de tesis se ha estructurado en dos partes: por una parte, la síntesis y caracterización de materiales sólidos inorgánicos porosos funcionalizados para el estudio y detección de aminas utilizando el procedimiento de "dosímetro químico", y en una segunda parte, se ha llevado a cabo la síntesis y caracterización de sólidos inorgánicos porosos funcionalizados para el estudio y detección de especies aniónicas mediante el procedimiento de "ensayos por desplazamiento".
[CA] La tesis doctoral que es presenta sota el títol "Hybrid inorganic-organic materials for the optical recognition of neutral and anionic species" ha tingut com objectiu principal la síntesi i caracterització de materials híbrids orgànic-inorgànics basats en la combinació dels principis de la Química Supramolecular i la Ciència dels Materials. Estudis recents corroboren que la cooperació entre aquestes dues àrees de la Química permet simular el que ja fa milions d'anys realitzen de forma natural els organismes vius. A nivell cel·lular, moltes de les funcions vitals estan relacionades amb l'habilitat d'un receptor concret per a reconèixer una espècie determinada, donant una resposta específica. Però el que és més interessant, és que als organismes vius, la majoria d'aquests sistemes no existeixen en forma de molècules dissoltes, sinó que estan units amb major o menor flexibilitat a un esquelet bio(in)orgànic. Quan imitem aquests sistemes tenint en compte la química supramolecular i analítica, ens trobem que necessitem d'una molècula indicadora que sigui capaç d'unir-se a l'espècie que volem detectar i que alhora, aquesta unió produeixi un canvi en les propietats fisico-químiques de l'entitat per produir una senyal. Però a més, si aprofitem el fet que els materials silícics nanoestructurats presenten una alta estabilitat física i química i que proporcionen cavitats on es pot allotjar el sistema sensor, tenim la combinació híbrida orgànica-inorgànica sintètica semblant a la natural. Per tal de desenvolupar aquesta idea, hem utilitzat sistemes sensors ampliament estudiats en procediments de reconeixement molecular en dissolució aquosa i els hem aplicat als materials híbrids orgànic-inorgànics. Així el present treball de Tesis s'ha estructurat en dues parts: per una banda, la síntesis i caracterització de materials sòlids inorgànics porosos funcionalitzats per l'estudi i detecció d'amines utilitzant el procediment de "dosímetre químic", i en una segona part, s'ha realitzat la síntesis i caracterització de sòlids inorgànics porosos funcionalitzats per a l'estudi i detecció d'espècies aniòniques mitjançant el procediment "d'assajos per desplaçament".
Comes Navarro, M. (2016). Hybrid inorganic-organic materials for the optical recognition of neutral and anionic species [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/62153
TESIS
Sorribas, Mellado Juan José. "Biological control of California red scale, Aonidiella aurantii (Hemiptera: Diaspididae): spatial and temporal distribution of natural enemies, parasitism levels and climate effects." Doctoral thesis, Universitat Politècnica de València, 2012. http://hdl.handle.net/10251/14794.
Full textSorribas Mellado, JJ. (2011). Biological control of California red scale, Aonidiella aurantii (Hemiptera: Diaspididae): spatial and temporal distribution of natural enemies, parasitism levels and climate effects [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/14794
Palancia
Santos, Figueroa Luis Enrique. "New approaches for the development of chromo-fluorogenic sensors for chemical species of biological, industrial and environmental interest." Doctoral thesis, Universitat Politècnica de València, 2015. http://hdl.handle.net/10251/43216.
Full textSantos Figueroa, LE. (2014). New approaches for the development of chromo-fluorogenic sensors for chemical species of biological, industrial and environmental interest [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/43216
TESIS
Premiado
Sheikh, MD Neaz. "Seismic assessment of buildings in Hong Kong with special emphasis on displacement-based approaches." Thesis, Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B31456662.
Full textWalbert, Katrin. "Ectomycorrhizal communities associated with a Pinus radiata plantation in the North Island, New Zealand." Lincoln University, 2008. http://hdl.handle.net/10182/658.
Full textGojuri, Arun. "Stability of End Notched Flexure Specimen." Thesis, Högskolan i Skövde, Institutionen för teknik och samhälle, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-4487.
Full textDickens, Jeremy Kenneth. "Taxonomy of Trogon rufus (Gmelin, 1788) and Amazonian ring-shaped clinal variation." Universidade de São Paulo, 2015. http://www.teses.usp.br/teses/disponiveis/38/38131/tde-15022016-164253/.
Full textNós revisamos a taxonomia do complexo Trogon rufus sob o conceito Biológico de Espécies. Unidades taxonômicas possíveis, quebras e zonas de transição taxonômicas foram definidas usando mapas de calor e isofenas (linhas de contorno de fenótípo) baseados em caráteres de cor, barramento e morfometria. Esses possíveis táxons foram testados pelas análises de discriminantes. Dados de coloração foram obtidos por meio de espectrometria, e os padrões de barramento por meio de fotos de alta qualidade. Nós encontramos quatro espécies biológicas distintas Trogon chrysochloros Pelzeln 1856, da Mata Atlântica, diagnosticável pelo barramento mais escuro e denso na face inferior da cauda e coberteiras da asa, maior tamanho corpóreo, canto mais rápido, com mais notas e de frequência mais alta. Suas partes superiores (cabeça, dorso e cauda) variam de azul a verde acobreado com o aumento da altitude. O bico também é relativamente menor e mais serrilhado, o que está ligado a uma dieta que consiste quase exclusivamente de grandes artrópodes, fazendo desta espécie o Trogon mais insetívoro do mundo, o que deve ser a razão de sua relativa raridade quando comparado a outros Trogonidae com os quais vive em simpatia. Trogon tenellus Cabanis 1862, da América Central, e Trogon cupreicauda Chapman 1914, do Chocó-Magdalena, formam um caso clássico de espécies biológicas, entrando em contato no extremo noroeste da província de Chocó, na Colômbia, sem a presença de formas intermediárias. T. tenellus é identificável pela face superior da cauda azul ou azul esverdeado, anel perioftálmico azul ou cinza, tarso cinza, e voz com de 2 a 4 notas, maior duração das notas e maior mudança entre frequência de pico e frequência alta entre a nota introdutória e nota principal. Essas características contrastam com a cor verde-oliva brilhante da face superior da cauda, anel perioftámico amarelo, tarso geralmente oliva, presença de marrom claro na face inferior da cauda das fêmeas e canto com entre 6 e 8 notas, de menor duração, pouca mudança na frequência entre a primeira nota e o canto principal de T. cupreicauda. Este varia clinalmente de azul para uma plumagem mais verde acobreada e de barramento preto mais espesso para mais fino em uma gradiente da costa do Pacífico, do noroeste do Equador até o Vale do Magdalena. A maior distinção de estados de caráter relativa a T. tenellus na região onde os dois grupos se encontram provê uma possível evidência de deslocamento de caracteres como resultado de exclusão competitiva entre estas duas espécies, mantendo suas distribuições parapátricas. A população amazônica pertence a única espécie biológica Trogon rufus Gmelin 1788, mas com duas formas altamente distintas que designamos como Trogon rufus rufus do Escudo Guianense, e Trogon rufus sulphureus no sul e oeste da Amazônia, com a qual amazonicus de Todd é sinonimizada. Estas são morfologicamente, e em menor escala, vocalmente distintas nas duas margens do baixo Rio Negro e áreas abertas e/ou montanhosas da bacia do Rio Branco, mas apresentam troca de caracteres limitada nas longitudes entre 52 e 58 Oeste na margem sul do Rio Amazonas, centrado nos arredores do Rio Arapiuns, na margem esquerda da foz do Tapajós. Nós postulamos que isto é um resultado de contato secundário, como consequência de mudanças no curso principal do Rio Amazonas em tempos de níveis mais baixos do mar durante o Plio-Pleistoceno. T. r. sulphureus é identificado pela coloração tipicamente acobreada da face superior da cauda com uma banda sub-terminal de tonalidade esverdeada, anel perioftálmico amarelo, barras negras espessas e de baixa densidade na face inferior da cauda e nas coberteiras das asas e pela ausência de uma faixa peitoral. Em certos casos eles também podem ser distinguíveis pela voz com uma nota introdutória de maior frequência e/ou uma modulação descendente mais pronunciada no canto principal. Este grupo varia clinalmente em gradiente de oeste para leste, de uma coloração cobre forte até verde oliva na face superior da cauda com faixa sub-terminal mais ou menos distinta, anel perioftálmico azul, presença ou ausência de uma faixa peitoral branca e barramento na face inferior da cauda e coberteiras de menor espessura e, consequentemente, maior densidade. Nossos dados apontam que estes caracteres mudam linearmente entre sulphureus e rufus de acordo com a distância ao longo de uma gradiente clinal em forma de laço do Oeste Amazônico até o Escudo das Guianas, conectado pela zona de contato de Arapiuns, sugerindo isolamento por distância. Isto sugere um remanescente de um padrão de espécie em anel. Além disso, dois espécimes com possível mistura de caracteres foram de fato encontrados no alto Rio Negro e Pantepui, onde se espera que T. r. rufus e T. r. sulphureus entrem em contato, fechando o anel efetivamente. Ainda é necessário testar se Trogon rufus constitui uma espécie em anel válida, preferencialmente usando dados moleculares, mas este caso ilustra claramente que a distinção entre variação clinal e espécie em anel é uma questão de grau e não de tipo, com a formação de espécie em anel necessariamente passando por um estágio clinal sem sobreposição entre os grupos terminais. Nós assim sugerimos o conceito de espécie em laço, onde as formas terminais não se sobrepõem, mas são ligadas através de uma série de populações onde há fluxo gênico. Parece provável que estes padrões são mais amplamente distribuídos na Amazônia do que é sabido atualmente devido a uma propensão à variação clinal e especiação parapátrica causada por sua grande extensão geográfica e abundância de barreiras geográficas semipermeáveis. Em relação a população do Centro de Endemismo Pernambuco, os poucos registros sugerem que esta é uma unidade taxonômica válida. Este grupo apresenta uma combinação única de canto muito similar ao de T. r. sulphureus, devido à alta frequência da nota introdutória e pronunciada modulação descendente ao longo do canto principal, com uma maior amplitude da frequência, combinada a maior tamanho, bico serrilhado, e anel perioftálmico azul, mas isso requer confirmação. Este caso demanda atenção urgente, já que a população remanescente é muito pequena e de distribuição restrita ao município de Murici, em Alagoas.
Kerr, Geoffrey N. "The economics of managing congestion: with special reference to backcountry recreation." Lincoln University, 1992. http://hdl.handle.net/10182/1971.
Full textMalmqvist, Philip. "Monitoring of crack growth and crack mouth opening displacement in compact tension specimens at high temperatures : Development and implementation of the Direct Current Potential Drop (DCPD) method." Thesis, Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kau:diva-44493.
Full textMechanical engineering avdelningen på University of Idaho genomför just nu ett utvecklingsprojekt med syftet att utveckla ett komplett system för undersökning av krypnings, krypnings-utmattnings- samt utmattnings- egenskaper av metalliska material vid höga temperaturer upp till 650 ˚C med hjälp av kompakta spänningsprovstavar (CT specimens). Betydande ansträngningar har gjorts för att undersöka och förstå dessa fenomen, men flera problem kvarstår. Det är viktigt att djupare undersöka kopplingen mellan krypnings- och utmattningsegenskaper. Direct Current Potential Drop (DCPD) metoden är en vanlig metod vilken används för att undersöka, exempelvis, sprickinitiering, spricktillväxthastigheter och spricktillväxt. Tekniken utnyttjar faktumet att den elektriska resistansen i en provstav ändras med spricktillväxt. Genom att föra en konstant ström genom provstaven och sedan mäta den resulterande spänningen över sprickan, kan spricklängden relateras till uppmätt spänning. På samma sätt kan spricktillväxt relateras till spänningsförändringar. Standarder från American Society for Testing of Materials (ASTM) användes för att designa ett DCPD system samt en CT provstav. Utvecklings- och implementeringsprocessen var uppdelad i en analytisk och en experimentell del. Den slutgiltiga produkten bestod av en extensometer, för mätning av spricköppning vid höga temperaturer, och ett DCPD system, för mätning av spricktillväxt vid höga temperaturer, vilka kontrollerades av separata kontrollenheter. DCPD systemet bestod av en strömkälla och en nanovoltmeter tillsammans med Constantan kablar respektive NiCr60 kablar, vilka fastsättes mekaniskt. DCPD systemet levererade generellt sett tillfredställande resultat och hade kapacitet att generera tillräckligt precisa data för att producera en spricktillväxtkurva, da/dN vs. ΔK. Däremot, genom att utnyttja en resistanssvets, för att fastsätta DCPD-kablarna, tillsammans med en gemensam kontrollenhet för extensometern och DCPD systemet, kan det tänkas att bättre och mer tillgängliga resultat kunde åstadkommas.
De, Donno Giulia. "Three dimensional strain analysis of vertebrae with artificial metastases through digital volume correlation." Bachelor's thesis, Alma Mater Studiorum - Università di Bologna, 2020. http://amslaurea.unibo.it/19911/.
Full textJones, Jason R. "Morphological convergence and character displacement in two species of polymorphic salamanders (genus Plethodon) in eastern Tennessee." 2009. http://trace.tennessee.edu/utk_gradthes/90.
Full textTao, Shan-Ta, and 陶善達. "Examining the Pattern of Character Displacement of Two Sympatric Agamid Lizards in Northern Taiwan by Species Distribution Model." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/96303004999256740531.
Full text國立臺灣大學
生態學與演化生物學研究所
101
Character displacement hypothesis states: when species with character similarity coexist in the same community, the population in sympatric location would displace in one or more characters. The increased differences in character space would reduce the strength of inter-specific competition for limited resources. Both Japalura swinhonis and Japalura polygonata xanthostoma occur in northern Taiwan. The two congeners have similar morphology and ecology, yet different macro-habitats. I applied species distribution model to identify environmental features that describe their differences in macrohabitat use, and predict the potential contact zone of the two species. Then use the latter to examine the pattern of character displacement. The results of species distribution modeling showed the distance to human-use area and total area of forest contribute the most to the distribution of the two species. The models allowed me to successfully locate four main regions of species coexistence. I found evidence for character displacement in most sympatric locations of Japalura swinhonis and Japalura polygonata xanthostoma. In four of the sympatric locations I surveyed, three of them showed significant intra-specific differences in their morphology between sympatric and allopatric locations. The head related parameters were consistently smaller for both species. While inter-specific difference of bite force related characters were greater in the sympatric than allopatric locations, characters related to sprint speed were more similar in the sympatric locations. Character displacement may be effect by inter-specific competition and predation risk in sympatric location, therefore, the characters related to sprint speed would be more similar.
Rachalewski, Michał. "Weak and strong invaders: which biotic factors shape interactions among Ponto-Caspian invasive gammaridean species." Phd diss., 2019. http://hdl.handle.net/11089/31472.
Full textRozprawa doktorska dra Michała Rachalewskiego pt. „Weak and strong invaders: which biotic factors shape interactions among Ponto-Caspian invasive gammaridean species?” otrzymała nagrodę w VII edycji Konkursu „Ekologiczny magister i doktor" w kategorii ekologiczny doktor. Zwycięska praca została napisana pod kierunkiem naukowym dr hab. Karoliny Bąceli-Spychalskiej z Katedry Zoologii Bezkręgowców i Hydrobiologii UŁ. Konkurs „Ekologiczny magister i doktor” organizowany jest przez Wojewódzki Fundusz Ochrony Środowiska i Gospodarki Wodnej w Łodzi. Celem Konkursu jest wyłonienie przez Zarząd WFOŚiGW w Łodzi najlepszych prac magisterskich i rozpraw doktorskich z dziedziny ochrony środowiska, które oceniane były zarówno pod względem naukowym jak i praktycznym.
The aim of this thesis was to investigate interactions and possible biotic factors that could be agents modulating coexistence and dispersal of three most widespread Ponto-Caspian species Dikerogammarus villosus (Sovinsky, 1894), Dikerogammarus haemobaphes (Eichwald, 1841) and Pontogammarus robustoides (G.O. Sars, 1894). Each chapter presented in this thesis is focused on a different biotic factor that defines the boundaries of possible coexistence of the studied species. This thesis fills some gaps in knowledge about possible ecological mechanisms that stand behind the invasion of those animals. Thus, their temperature preferences were investigated to find whether this factor might determine coexistence of species by relocation leading to their spatial segregation among microhabitats. Ponto-Caspian amphipods are often highly infected with microsporidian parasites, which coevolved with them in their native region and undergo the invasion with their hosts to Europe, Thus, incorporation of microsporidia into study upon thermal preferences of Ponto-Caspian amphipods allowed to investigate both infection presence and temperature selection as agents capable of determining the possibility of coexistence of the studied amphipods. Therefore, physical and chemical contact with competitors, thermal preferences and possible modulators of these factors – microsporidian parasites were chosen as imsportant factors potentially affecting the intensity and direction of amphipod migrations. All ecological experiments were conducted with intention to define behaviour of each studied species while facing with those factors.
Polish National Science Centre grants 2011/03/D/NZ8/03012 and 2012/05/B/NZ8/00479
Almaraz, Elky. "The Interactions of Zinc Thiolate Complexes and Exogenous Metal Species: Investigations of Thiolate Bridging and Metal Exchange." 2009. http://hdl.handle.net/1969.1/ETD-TAMU-2009-05-536.
Full textSchuldt, Bernhard. "Effects of experimental drought on hydraulic properties and leaf traits of upper canopy and understory tree species in a perhumid tropical forest in Central Sulawesi, Indonesia." Doctoral thesis, 2010. http://hdl.handle.net/11858/00-1735-0000-0006-ADD8-8.
Full textLee, Tai-Kuang, and 李泰廣. "Application of Endochronic Viscoplasticity with Cyclic Damage to Sn/3.5Ag/0.75Cu Solder Joint Specimens under Cyclic Proportional Displacement Path." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/62006065891178527327.
Full text國立成功大學
工程科學系碩博士班
95
In order to find stress-strain-damage behavior of solder ball by using solder joint specimen, this thesis defined, at first, the stiffness of material testing system, whose value could be determined from the slope of linear range of loading or unloading of the load-displacement hysteresis loop. Within this range, the solder joints behaved linear elastic with Young’s modulus and shear modulus of bulk material. As a result, the (elastic) stiffness of solder joint specimen under proportional displacement path (Φ) could be determined. Employing the series combination of spring for material testing system, the stiffness of grips could be calculated, whose value was fixed under its corresponding proportional displacement path. Consequently, the load-displacement hysteresis loop of solder joint specimen could be constructed. In this paper, isothermal undamage simple shear test data of solder joint specimen having 9 Sn/3.5Ag/0.75Cu balls were used as a base to determine the kernel function of endochronic viscoplasticity and the material function in the intrinsic time measure whose values were increased from Φ=90° to 0° but decreased as increased of the effective inelastic strain amplitude. Based on these, the isotropic endochronic viscoplasticity with cyclic damage under various proportional displacement path was used to compute load-displacement hysteresis loops. The computational results were in excellent agreement with data. According to Lee’s evolution equation of cyclic damage and the small increase in effective inelastic strain amplitude with increasing cyclic number, the relationship between damage factor D and the cyclic number N could be derived: , here was increased both from Φ=90° to 0° and the increase of effective inelastic strain amplitude. But the trend of was reversed. Usage of data of D vs. N curves and load-displacement hysteresis loops of various Φ, critical values of damage factor could be determined, 0.4
Pei-ShingTsai and 蔡佩杏. "Endochronic Prediction of Fatigue Initiation Life of BGA (63Sn/37Pb and Sn/3.5Ag/0.75Cu) Solder Joint Specimens under Cyclic Oblique Displacement Test." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/14015946656193686440.
Full text國立成功大學
工程科學系碩博士班
98
In this paper, the force -oblique displacement correction methods of the BGA solder joint specimens and the values of grip stiffness were used to correct the force-oblique displacement curves of the 63Sn/37Pb BGA specimens into the force-displacement data of their solder balls under proportional strain cyclic test. The kernel function of Endochronic cyclic viscoplasticity of 63Sn/37Pb bulk material was employed to predict the cyclic proportional stress-strain curves and then construct the relationship of the effective inelastic strain amplitude and the effective stress amplitude : . Also the BGA oblique displacement amplitude has a relation with of solder ball by . This result connects the research of BGA solder joint specimen in industry and the research of constitutive models in academic. Based on physical phenomena, dependent damage degree depends positively on N cycle and , then the -modified damage power equation and the -Modified Lee-Coffin-Manson equation( -LCM) for the fatigue initiation life of solder ball: can be derived. Finally the -LBGA equation for the fatigue life of BGA specimens: can be obtained. Using the -LBGA equation, both of 63Sn/37Pb and Sn/3.5Ag/0.75Cu BGA fatigue life can be predicted very well.
Chang, Jun-Wei, and 張峻偉. "Prediction Fatigue Initiation Life of 63Sn/37Pb Solder Joint Specimens under Cyclic Proportional Displacement Path Via The Endochronic Viscoplasticity with Cyclic Damage." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/69684114299140282725.
Full text國立成功大學
工程科學系碩博士班
96
In 2007, for the solder joint Sn/3.5Ag/0.75Cu cyclic proportional displacement path, Lee and Lee proposed the modification of solder joint specimen with stiffness of material testing system, and figured out the grip stiffiness by using series connetion concept. In 2002, Park used the same way to make the experiment with 63Sn/37Pb solder joint. In this paper, the material parameters , and were determined with Lee and Chen research on a 63Sn/37Pb bar whose area is , and the length is . Combining the material parameters and specimen parameter which were getting from Lee and Lee to run the endochronic viscoplaticity increment form consideration, passed through above step to proof that whether the material parameters with same material but different geometry and size become changed or not. From the evolution equation of cyclic damage which proposed by Lee and Chen, getting a relationship between damage factor and cyclic fatigue life. In this paper, for a fixed damage parameter D=0.5, the figure displacement correspond to fatigue life, citing the damage parameter which was proposed by Lee and Chen to become the damage parameter daturn whose angle equal to 0, and citing the Sn/3.5Ag/0.75Cu solder joint specimen parameter proposed by Lee and Lee to obtain the damage parameters whose angle is equal to 45 or 90. From above information, citing the Coffin-Manson modification and combining with the critical damage parameter to estimate the fatigue initiation life, after that, establishing the relationship between system displacement range and effect inelastic strain range and combining the Coffin-Manson modification to obtain the initiation fatigue life immediately.
Lin, Tai-tin, and 林泰廷. "Prediction of Fatigue Initiation Life of BGA (Sn/3.5Ag/0.75Cu) Solder Joint Specimens under Cyclic Proportional Displacement Path via Damage Coupled Endochronic Viscoplasticity." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/05206097374183755900.
Full text國立成功大學
工程科學系碩博士班
97
The purpose of this paper is to investigate the fatigue initiation life prediction of BGA (Sn/3.5Ag/0.75Cu) solder joint specimens under mixed mode cyclic proportional displacement path( ) .First, by using the BGA solder joint standoff 0.52mm to adjust the displacement-loading data of the master's thesis of Lee, T. K. in 2007. And continue with using the material parameters and kernel function of Endochronic cyclic viscoplasticity to simulate cyclic stress-strain curve under proportional displacement path. Then using the effective inelastic strain and effective stress , the relation was established. This paper(1) aim to employ damage effective strain in parameter that depend on elastic strain energy density release rate and damage rate. (2)Using the definition of intrinsic damage time to establish evolution equation of intrinsic damage under cyclic proportional displacement path. This paper purpose the power form relation between damage accumulate rate and numbers of cycle N. Then damage factor can be derived from the relation, by cyclic loading amplitude vs. N data could compute and n. The results find that depend on , and , n is independence from . Endochronic fatigue life prediction under proportional displacement path , is independence from , but , therefore the result of figure vs. depend on , the result under the different scope of , Coffin-Manson relationship can be expressed by straight lines.