Relevant bibliographies by topics / The theory of critical distances

Contents

  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers
  6. Reports

Academic literature on the topic 'The theory of critical distances'

Author: Grafiati
Published: 28 June 2021
Last updated: 7 February 2022

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'The theory of critical distances.'

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.

Journal articles on the topic "The theory of critical distances"

1

Taylor, D. "The theory of critical distances." Engineering Fracture Mechanics 75, no. 7 (May 2008): 1696–705. http://dx.doi.org/10.1016/j.engfracmech.2007.04.007.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Taylor, David. "Microstructural Parameters in the Theory of Critical Distances." Materials Science Forum 567-568 (December 2007): 23–28. http://dx.doi.org/10.4028/www.scientific.net/msf.567-568.23.

Full text
Abstract:
The work described below investigates, for the first time, the link between microstructural parameters such as grain size and the length constant L which is known as the critical distance. L is frequently used in the prediction of failure processes such as brittle fracture and fatigue, initiated at stress concentration features such as notches. Values of L were calculated using data from the literature on the effect of short cracks and notches in steels and ceramics. In some cases, simple relationships could be established between L and the grain size, or other microstructural features. Sometimes L was found to be much larger than anything in the microstructure and appeared to be related to the size of the damage zone at failure.
APA, Harvard, Vancouver, ISO, and other styles
3

Taylor, David. "The Theory of Critical Distances: A link to micromechanisms." Theoretical and Applied Fracture Mechanics 90 (August 2017): 228–33. http://dx.doi.org/10.1016/j.tafmec.2017.05.018.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Vargiu, Filippo, Derek Sweeney, Donato Firrao, Paolo Matteis, and David Taylor. "Implementation of the Theory of Critical Distances using mesh control." Theoretical and Applied Fracture Mechanics 92 (December 2017): 113–21. http://dx.doi.org/10.1016/j.tafmec.2017.05.019.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Taylor, David. "Applications of the theory of critical distances in failure analysis." Engineering Failure Analysis 18, no. 2 (March 2011): 543–49. http://dx.doi.org/10.1016/j.engfailanal.2010.07.002.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Taylor, David. "The Theory of Critical Distances applied to multiscale toughening mechanisms." Engineering Fracture Mechanics 209 (March 2019): 392–403. http://dx.doi.org/10.1016/j.engfracmech.2019.02.012.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Suknev, S. V. "Extending the theory of critical distances to quasi-brittle fracture." Theoretical and Applied Fracture Mechanics 114 (August 2021): 102996. http://dx.doi.org/10.1016/j.tafmec.2021.102996.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Cicero, S., V. Madrazo, and I. A. Carrascal. "Estimation of Fracture Toughness by Testing Notched Fracture Specimens and Applying the Theory of Critical Distances." ISRN Materials Science 2012 (September 17, 2012): 1–8. http://dx.doi.org/10.5402/2012/689386.

Full text
Abstract:
This paper applies a methodology that allows the fracture toughness of a given material to be estimated by testing notched fracture toughness specimens and applying the Theory of Critical Distances, which requires the elastic stress field at the notch tip to be determined by finite elements simulation. This methodology, which is not intended to substitute any standardised fracture characterisation procedure, constitutes an alternative in those situations where pre-cracking processes may be too time-consuming, too expensive or, simply, cannot be performed. It comprises testing two notched specimens with different notch radii, defining the corresponding stress fields at fracture by using finite elements analysis, and applying the Theory of Critical Distances in order to calibrate the material’s critical distance and to apply the corresponding apparent fracture toughness formulation. The methodology has been applied to two different materials, PMMA and Al7075-T651, and the results have proven that, as long as the Theory of Critical Distances has been applied within its validity range, the fracture toughness estimations are highly accurate.
APA, Harvard, Vancouver, ISO, and other styles
9

Hattori, Toshio, Muhammad Amiruddin Bin Ab Wahab, and Minoru Yamashita. "Low Cycle Fatigue Estimation Based on the Critical Distance Stress Theory." Advanced Materials Research 891-892 (March 2014): 1773–78. http://dx.doi.org/10.4028/www.scientific.net/amr.891-892.1773.

Full text
Abstract:
Generally the critical distance stress theory was applied for the fatigue limit estimation of general structures using fatigue limit of smooth specimen (σw0), and threshold stress intensity factor range (Kth). In this paper we extended this method for the estimation of low cycle fatigue life too. In this method we define the critical distance (rc) on static strength conditions, which is calculated using ultimate tensile strength (σB) and fracture toughness (KIC), in addition to the critical distance on fatigue limit condition (rc). Then the critical distances of any low cycle fatigue conditions can be calculated by interpolation of critical distance on fatigue limit (rc) with critical distance on static strength (rc). By unifying these low cycle fatigue life estimation method with high cycle fatigue limit estimation method we can estimate the full range fatigue life easily. And to confirm the availability of this estimation method we perform the fatigue test for any stress concentration specimens.s
APA, Harvard, Vancouver, ISO, and other styles
10

Wahab, Muhammad Amiruddin Bin Ab, Niu Jie, Toshio Hattori, and Minoru Yamashita. "Fatigue Strength and Life Estimation Methods Using Critical Distance Stress Theory." Advanced Materials Research 694-697 (May 2013): 853–63. http://dx.doi.org/10.4028/www.scientific.net/amr.694-697.853.

Full text
Abstract:
Generallythe critical distance stress theory was applied for the fatigue limitestimation of general structures. In thismethod, it needs only two parameters, fatiguelimit of smooth specimen (σw0), and threshold stress intensityfactor range (∆Kth). In this paper we extended this method for theestimation of low cycle fatigue lifetoo. In this improvement wedefine the critical distance (rc’) on static strength conditions,which is calculated using ultimate tensile strength (σB) andfracture toughness (KIC), in addition to the critical distance onfatigue limit condition (rc). Then the critical distances of any lowcycle fatigue conditions can be calculated by interpolation of criticaldistance on fatigue limit (rc)with critical distance on staticstrength (rc’). By unifying these low cycle fatigue life estimationmethod with high cycle fatigue limit estimation method we can estimate the fullrange fatigue life easily. And to confirm the availabilityof this estimation method we perform the fatigue test for circlehole specimens, sharp V notch specimens andfretting fatigue specimens.
APA, Harvard, Vancouver, ISO, and other styles
More sources

Dissertations / Theses on the topic "The theory of critical distances"

1

Gorouhi, Hadi. "Novel fatigue analysis of old metallic bridges through the theory of critical distances (TCD)." Thesis, University of Surrey, 2018. http://epubs.surrey.ac.uk/845859/.

Full text
Abstract:
Majority of the railway bridges built in the UK and around the world before the middle of 20th century are of riveted type made of wrought iron or old mild steel. Many of these bridges are approaching their useful design life. Despite their old age, many are still in operation. In-service fatigue cracking and failure in the riveted double-angle connections in such bridges, especially in the rivets and outstanding leg of the angles, had been reported in the past. These connections are one of the most fatigue-prone details found in riveted railway bridges. Fatigue assessment of riveted details is generally based on a global life assessment, such as the S-N approach. The S-N approach involves the challenge of selecting an appropriate detail classification on an S-N basis as well as defining a nominal stress, free from stress raiser effects. By contrast, local stress methods, such as the Theory of Critical Distances (TCD), which directly considers the effect of stress raisers and loading conditions through finite element analysis, may provide a more favourable option for fatigue evaluation since it avoids the need for S-N classification and nominal stress calculation. In this thesis, the fatigue life prediction capability of the TCD and the S-N methods when applied to riveted bridge details was investigated through finite element analysis of simple and complex riveted details focusing on stringer-to-floor-beam connections. The fatigue life predictions of both the TCD and the traditional S-N methods were compared with the experimental data. Thus, a database of static and fatigue tests available in the literature on structural wrought iron and mild steel riveted details and connections was created. The choice of the suitable modelling techniques for the finite element analysis of the riveted details was verified using a benchmark study on a riveted single lap joint. The critical length vs. number of cycles to failure relationship, L vs. Nf, necessary for fatigue analysis based on the TCD was calibrated for structural wrought-iron material obtained from a real bridge. Fatigue assessment of the investigated riveted details was performed based on both the TCD and the S-N methods to quantify the differences. The results of this study showed that the TCD was successful in predicting fatigue life with the predictions falling within the constant amplitude scatter bands of the experimental data. In the single lap joint, the TCD method accurately estimated the average rivet clamping force values developed in the rivets of the specimens experimentally investigated. In the butt joints, the results of the TCD method was found to conformed well with the experimental research in the literature by predicting higher rivet clamping forces in the specimens with longer grip length. The novel formalisations of the TCD effectively predicted the fatigue life of full-scale riveted built-up girders with the results in the medium- and high-cycle always falling inside the CA scatter bands of the experimental data. The accuracy of the TCD method in estimating the rivet clamping forces present in the rivets of the investigated girders was found to be very high. The TCD was highly accurate when used to estimate the fatigue life of different components of the stringer-to-floor-beam connection subjected to four-point bending with the predictions falling in the scatter of the available experimental data. The hotspot locations identified by the TCD method were consistent with the results of the experimental study. By contrast, the predictions of the S-N method were very nonconservative in the case of the stringer-to-floor-beam connections (up to a factor of 2900). In general, the S-N method predictions were found to be sensitive to the choice of the detail classification. In the case of the stringer-to-floor-beam connection, Modified Class B resulted in the most nonconservative results (up to a factor of 10) when compared with the results of the other S-N classifications. The findings of this thesis may provide the bridge owners and authorities with a safe and effective alternative method in determining the remaining fatigue life of such bridge details.
APA, Harvard, Vancouver, ISO, and other styles
2

Louks, Richard. "Developing the 'Theory of Critical Distances' for practical integrity assessment of real-life structural components." Thesis, University of Sheffield, 2016. http://etheses.whiterose.ac.uk/14352/.

Full text
Abstract:
This PhD thesis details the research conducted to answer three questions in the field of fracture and fatigue engineering. The opening chapters provide fracture and fatigue background theory as well as a more comprehensive review of the Theory of Critical Distances (TCD), a theory proven to be successful in the assessment of components containing stress concentration features. Chapter 4 details an engineering approach based on the TCD for the static assessment of engineering components containing stress concentrators made of brittle, quasi-brittle and ductile materials; and loaded by any combination of static forces. To validate the method, 1744 experimental data was taken from technical literature is provided in Annex A. Each data was modelled using FE software, the extracted stress data was then post-processed using this reformulation of the TCD. The results obtained were compared to the commonly used Hot-Spot Stress-Method, across the same set of data there was an order of magnitude improvement in accuracy, the TCD Point Method giving an average error less than 30% whilst the HSSM gave an average error greater than 300%. Chapter 5 is concerned with the use of the linear-elastic TCD to assess notched metallic components in the high-cycle fatigue regime at elevated temperatures. Full details of two experimental programmes are provided, notched samples of a low carbon steel C45 and an aluminium alloy A319 T7 was tested, the results are provided in Annex C. Additional experimental data was taken from technical literature to further validate the method. The results showed that the approach was highly accurate with errors falling within ±20%. The 6th Chapter gives account of a study into the combined use of the TCD and the Modified Wöhler Curve Method (MWCM) to accurately and efficiently assess metal engineering components IV containing complex 3D stress raisers experiencing complex load histories that resulted in fatigue failures in the medium- and high-cycle fatigue regime. The method is based on critical plane theory which assumes that fatigue cracks initiate on the material plane experiencing the maximum shear stress amplitude. The method was proven to be successful independent of the stress raiser geometry and the complexity of the load history, typically returning errors of ±20%. Chapters 4-6 each have their individual conclusions and suggestions for further work, chapter 7 gives a summary of the conclusions and chapter 8 provides some suggestions for further work.
APA, Harvard, Vancouver, ISO, and other styles
3

Yin, Taixiang. "On the use of the Theory of Critical Distances to design notched metallic components against dynamic loading." Thesis, University of Sheffield, 2017. http://etheses.whiterose.ac.uk/16464/.

Full text
Abstract:
The Theory of Critical Distances (TCD) is a well-known design method allowing the strength of notched/crack components to be estimated accurately by directly post-processing the entire linear elastic stress fields damaging the material in the vicinity of the stress raisers being designed. By taking full advantage of the TCD’s unique features, in this thesis, the TCD is reformulated to make it suitable for predicting the strength of notched metallic materials subjected to dynamic loading by post-processing both linear elastic and elastoplastic stress distributions. The accuracy and reliability of the proposed reformulation of the linear elastic TCD were checked against a number of experimental results generated by testing, under different loading/strain/displacement rates, notched cylindrical samples of aluminium alloy 6063-T5, titanium alloy Ti–6Al–4V, aluminium alloy AlMg6, and an AlMn alloy. To further validate the proposed design method also different data sets taken from the literature were considered. Such an extensive validation exercise allowed us to prove that the proposed reformulation of the TCD is successful in predicting the dynamic strength of notched metallic materials falling within an error interval of ±20%. Such a high level of accuracy is certainly remarkable, especially in light of the fact that it was reached without the need for explicitly modelling the stress vs. strain dynamic behaviour of the investigated ductile metals. Additionally, the FEM with Simplified-Johnson Cook elastoplastic material model was used to predict the dynamic strength of notched metallic material falling within an error interval of ±20%. Moreover, the elastoplastic TCD was also provided to be capable of predicting the dynamic strength of notched metallic materials falling within an error interval of ±6%.
APA, Harvard, Vancouver, ISO, and other styles
4

Bagni, Cristian. "Formalisation of a novel finite element design method based on the combined use of gradient elasticity and the Theory of Critical Distances." Thesis, University of Sheffield, 2016. http://etheses.whiterose.ac.uk/17118/.

Full text
Abstract:
The present research work is dedicated to the development, implementation and validation of a unified finite element methodology based on the combination of gradient elasticity and the Theory of Critical Distances, for the static and high-cycle fatigue assessment of notched engineering components. The proposed methodology, developed for plane, axisymmetric and three-dimensional problems, takes full advantage of both the TCD's accuracy in estimating static and high-cycle fatigue strength of notched components and of the computational efficiency of gradient elasticity in determining non-local stress fields whose distribution fully depends on the value of the adopted length scale parameter. In particular, the developed methodology, due to the ability of gradient elasticity to smooth stress fields in the vicinity of notch tips, has the great advantage of allowing accurate and reliable static and fatigue assessments of notched components by directly considering the relevant gradient-enriched stresses at the hot-spot on the surface of the component, in contrast to existing conventional approaches that require the knowledge of the failure location into the material a priori. This advantage, together with the fact that the proposed methodology can be easily implemented in commercial finite element software, makes the developed methodology a powerful and easy-to-use tool for the static and fatigue design/assessment of notched components. The developed methodology is accompanied by an accurate investigation of the best integration rules to be used as well as a comprehensive convergence study both in absence and presence of cracks, leading to a practical guideline on optimum element size. The proposed gradient-enriched methodology has been validated against a large number of problems involving notched components subject to both static and fatigue loading, covering a wide range of materials, geometries and loading conditions, clearly showing its accuracy and versatility. The developed gradient-enriched methodology has also been extended to the study of the dynamic behaviour of visco-elastic materials subject to vibration.
APA, Harvard, Vancouver, ISO, and other styles
5

Madrazo, Acebes Virginia. "Análisis, desarrollo y aplicación de la teoría de las distancias críticas en la evaluación en rotura de componentes estructurales." Doctoral thesis, Universidad de Cantabria, 2013. http://hdl.handle.net/10803/110732.

Full text
Abstract:
En este trabajo se valida la TDC en dos materiales con comportamiento elástico–lineal en estado fisurado: el polímero PMMA y la aleación Al7075-T651. La validación se ha realizado sobre probetas de fractura y se han establecido rangos de validez de la TDC en régimen elástico-lineal. Igualmente, se demuestra la aplicabilidad de la TDC para la evaluación en rotura de componentes con cualquier concentrador de tensiones (entalla en U, entalla en V, taladro circular, etc) y para cargas de distinta naturaleza (tracción vs. Flexión). Además, se plantea y valida un modelo de evaluación de la integridad estructural de componentes con entallas que combina la TDC con los Diagramas de Fallo, extendiendo el rango de aplicación de la TDC a situaciones con comportamiento elastoplástico. Finalmente, el análisis se completa con un detallado estudio mediante microscopía electrónica de barrido de los micromecanismos de fractura de las probetas analizadas.
This study validates the TDC in two materials with linear elastic behavior in cracked conditions: polymer PMMA and alloy AL7075-T651. The validation has been performed on fracture specimens and validity ranges of the TDC in linear elastic regime have been established. Similarly, it is demonstrated the applicability of the TDC for evaluation of components containing any kind of stress riser (e.g., U-notch, V-notch, hole circular, etc.) and subjected to loads of different nature (tensile vs. bending). In addition, a model for the structural integrity assessment of notched components is presented and validated, combining the TDC with Failure Assessment Diagram. This extends the vailidity range of the TDC to situations with elastic-plastic behaviour. Finally, the analysis is completed with a detailed study by scanning electron microscopy of the fracture micromechanisms of the samples being analysed.
APA, Harvard, Vancouver, ISO, and other styles
6

Tilak, Shantanu Amod. "Alternative lifeworlds on the Internet: Habermas and democratic distance education." The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1587177594821112.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Leidermark, Daniel. "Crystal plasticity and crack initiation in a single-crystal nickel-base superalloy : Modelling, evaluation and appliations." Doctoral thesis, Linköpings universitet, Hållfasthetslära, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-72093.

Full text
Abstract:
In this dissertation the work done in the projects KME-410/502 will be presented.The overall objective in these projects is to evaluate and develop tools for designingagainst fatigue in single-crystal nickel-base superalloys in gas turbines. Experimentshave been done on single-crystal nickel-base superalloy specimens in order toinvestigate the mechanical and fatigue behaviour of the material. The constitutivebehaviour has been modelled and veried by FE-simulations of the experiments.Furthermore, the microstructural degradation during long-time ageing has been investigatedwith respect to the material's yield limit. The eect has been includedin the constitutive model by lowering the resulting yield limit. Moreover, the fatiguecrack initiation of a component has been analysed and modelled by using acritical plane approach in combination with a critical distance method. Finally, asan application, the derived single-crystal model was applied to all the individualgrains in a coarse grained specimen to predict the dispersion in fatigue crack initiationlife depending on random grain distributions. This thesis is divided into three parts. In the rst part the theoretical framework,based upon continuum mechanics, crystal plasticity, the critical plane approachand the critical distance method, is derived. This framework is then used in thesecond part, which consists of six included papers. Finally, in the third part, detailsof the used numerical procedures are presented.
APA, Harvard, Vancouver, ISO, and other styles
8

Birochi, Renê. "Uma abordagem crítica para a educação a distância orientada para as microfinanças." reponame:Repositório Institucional do FGV, 2011. http://hdl.handle.net/10438/8189.

Full text
Abstract:
Submitted by Cristiane Oliveira (cristiane.oliveira@fgv.br) on 2011-05-25T13:22:05Z No. of bitstreams: 1 71070100691.pdf: 2593583 bytes, checksum: 2edc9e752f6477521da46c510506f31e (MD5)
Approved for entry into archive by Suzinei Teles Garcia Garcia(suzinei.garcia@fgv.br) on 2011-05-25T13:40:05Z (GMT) No. of bitstreams: 1 71070100691.pdf: 2593583 bytes, checksum: 2edc9e752f6477521da46c510506f31e (MD5)
Approved for entry into archive by Suzinei Teles Garcia Garcia(suzinei.garcia@fgv.br) on 2011-05-25T13:40:36Z (GMT) No. of bitstreams: 1 71070100691.pdf: 2593583 bytes, checksum: 2edc9e752f6477521da46c510506f31e (MD5)
Made available in DSpace on 2011-05-25T14:44:15Z (GMT). No. of bitstreams: 1 71070100691.pdf: 2593583 bytes, checksum: 2edc9e752f6477521da46c510506f31e (MD5) Previous issue date: 2011-02-23
As investigações sobre as práticas educacionais a distância e os respectivos usos de mídias para esse fim remontam aos estudos por correspondência do século XIX. A educação a distância (EAD), mediada pelas tecnologias de informação e comunicação (TICs), é um fenômeno recente, característico da sociedade pós-industrial, que utiliza grande diversidade de recursos, processos e meios para promover a educação. Historicamente, a área de EAD apresenta escassez de estudos teóricos sobre os fundamentos de suas práticas. A sua literatura também revela ausência, quase completa, de abordagens baseadas nas tradições do pensamento crítico, como, por exemplo, a teoria da estruturação (GIDDENS, 1984) ou a pedagogia crítica (FREIRE, 1987). Tendo isso em vista, procurou-se realizar uma revisão dessas abordagens orientando-as à EAD. Essa revisão teve como objetivo contribuir com os debates sobre os fundamentos teóricos da EAD, iniciados em 1960, visando ampliar os limites de suas práticas – já que atualmente, ainda predominam mecanismos típicos da sociedade industrial, como por exemplo, a replicação em massa de conteúdos educacionais. Para atender a esse objetivo, este trabalho de tese realizou um exame das principais teorias da EAD e se concentrou em encontrar uma fundação teórica comum, expressa por alguns conceitos essenciais. Esses conceitos que emergiram das análises foram re-interpretados por meio da influência das tradições do pensamento crítico, provenientes dos domínios da filosofia, sociologia, educação e comunicação. Esse processo parcimonioso de revisão conceitual da EAD foi enriquecido pela inclusão de dois eixos adicionais de investigação: a educação de adultos e a educação financeira. Ao final dessa revisão foi constituído um quadro teórico que funcionou como um núcleo central deste estudo. Esse núcleo sofreu influências e alterações substantivas de informações provenientes do campo empírico de investigação. O campo empírico representou a oportunidade de investigar o objeto principal desta tese, orientado para compreender como um programa de EAD deve ser constituído para atuar como um instrumento de emancipação socioeconômica de microempresários pobres, usuários de serviços microfinanceiros. Para atender esse objetivo, foi realizado um estudo de caso instrumental utilizando-se procedimentos metodológicos de pesquisa qualitativa. O município de Autazes, no Estado do Amazonas, foi escolhido para ser estudado, pois sofreu um expressivo crescimento socioeconômico recente, ocorrido após a instalação de pontos de acesso a serviços financeiros, com uso de mediação tecnológica. Esse crescimento resultou em desenvolvimento econômico, associado ao agravamento de tensões sociais, dentre as quais, o endividamento financeiro da população. O município integra, também, uma rede pública de ensino na modalidade a distância, provida pelo governo do Estado, que tem sido objeto de destacados prêmios internacionais. Como resultado deste trabalho de tese, foi possível consolidar as contribuições teóricas e empíricas em um quadro teórico final, que tem como objetivo orientar a elaboração de novas teorias de EAD críticas. Da mesma forma, foi proposto um modelo inédito para a EAD crítica, voltado para a prática dessa modalidade de educação.
Investigations on distance education practices, and the respective uses of media for this application, hark back to correspondence courses of the 19th Century. Distance education (DE) mediated by information and communication technologies (ICTs) is a recent development characterized by a post-industrial society which exploits a broad array of resources, processes and media to promote education. Historically, the DE domain has been the subject of scant theoretical studies investigating the framework underlying DE practices. The literature also reveals an almost total absence of approaches based on the traditions of critical thinking, such as the theory of structuration (GIDDENS, 1984) and critical pedagogy (FREIRE, 1987). Against this background, an analytical review of these approaches was carried out, relating them to DE. The aim of this review was to contribute to the discussion on the theoretical foundations of DE, first established in 1960, in a bid to broaden the scope of DE practices. Indeed, mechanisms typical of an industrial society still predominate in DE, such as mass replication of educational content. In order to address this issue, an examination of the core theories of DE was conducted seeking to identify a common theoretical framework, underpinned by a few seminal concepts. The concepts which emerged in the analysis were reinterpreted in the context of critical traditions, drawn from the disciplines of philosophy, sociology, education and communication. This parsimonious process of conceptual review of DE was enriched by the inclusion of two additional lines of investigation: adult education and financial education. The review process culminated in the devising of a theoretical framework which served as the central core of this investigation. The framework underwent major influences and substantive changes, stemming from the empirical field of investigation. The empirical field represented an opportunity to investigate the main focus of this thesis, namely, to elucidate how DE programs should be structured in order to act as instruments of socioeconomic emancipation of business owners that are, in turn, users of microfinancial services. In order to address this theme, an instrumental case study was performed based on qualitative research methods and procedures. The municipality of Autazes in the state of Amazonas was elected as the target of this study, given its recent significant socioeconomic growth following installation of points of access to financial services enabled by ICTs. This growth led to economic development together with worsened social tensions, including increased indebtedness of the population. The municipality also boasts a distancebased public education network provided by the government of the state of Amazonas, an initiative which has garnered several recognized international awards. The theoretical and empirical contributions of this study have been consolidated into a final theoretical framework which may serve as a basis for devising new critical theories in DE. Finally, a new model of critical DE was proposed, aimed specifically at the practice of this mode of education.
APA, Harvard, Vancouver, ISO, and other styles
9

Malmberg, Ivan. "An analysis of iBeacons and critical minimum distances in device placement." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-187925.

Full text
Abstract:
This project has been carried out in, and under the supervision of the Mobile Services Laboratory at the department of Communication Systems, KTH. The task was to explore the technical specifics of the iBeacon technology and its practical limitations in terms of reliability and device placement. In plain text; how close the beacons can be placed to allow for reliable isolation of the pertinent beacon. The main method of reaching the set goal was data capture at certain key positions around the mounted beacons. The resulting data was processed, analyzed and visualized to provide an accessible overview. The measurements and data analysis resulted in fairly concrete data that most of all highlights the very real limitations, and also a word of caution regarding stretching the actual limitations of such a basic technology as it actually is.
Projektet har utförts på, och under överseende av Mobile Services Laboratory på avdelningen Kommunikationssystem vid KTH. Syftet med projektet var att utforska och undersöka de tekniska detaljerna kring iBeacon-teknologin samt dess praktiska begränsningar gällande dess tillförliglighet och fysiska placering av enheterna. I klartext; hur nära iBeacon-enheterna kan placeras samtidigt som en accepterbar nivå av tillförlitlighet gällande separation av den relevanta enheten kan nås. Huvudmetoden som användes för att nå målet var datainsamling på nyckelpositioner runt de monterade enheterna. Framtagen data behandlades, analyserades och visualiserades för att kunna framställa överblickbar data. Mätningarna och dataanlysen resulterade i konkret data som framförallt lyfter de de verkliga begränsningarna för teknologin, samt ett varningens ord om vilka problem som potentiellt kan uppstå när en såpass grundläggande teknik används på ett sätt den eventuellt inte är avsedd för.
APA, Harvard, Vancouver, ISO, and other styles
10

Goodsett, Mandi. "Determining the Extent to Which Information Literacy Online Learning Objects Follow Best Practices for Teaching and Assessing Critical Thinking." Cleveland State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=csu1526048546211971.

Full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Books on the topic "The theory of critical distances"

1

The theory of critical distances: A new perspective in fracture mechanics. Amsterdam: Elsevier, 2007.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
2

Liese, Friedrich. Convex statistical distances. Leipzig: B.G. Teubner Verlagsgesellschaft, 1987.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Liese, Friedrich. Convex statistical distances. Leipzig, Germany: Teubner, 1987.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

How, Alan. Critical Theory. London: Macmillan Education UK, 2003. http://dx.doi.org/10.1007/978-0-230-80237-7.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Hoy, David Couzens. Critical Theory. Oxford, UK: Blackwell Publishing, 1994.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

Rasmussen, David, and James Swindal. Critical Theory. 1 Oliver's Yard, 55 City Road, London EC1Y 1SP United Kingdom: SAGE Publications Ltd, 2004. http://dx.doi.org/10.4135/9781446261293.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Stuart, Sim. Introducing critical theory. Royston [England]: Icon, 2004.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Borin, Van Loon, and Appignanesi Richard 1940-, eds. Introducing critical theory. Royston: Icon Books, 2004.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Borin, Van Loon, and Appignanesi Richard, eds. Introducing critical theory. Cambridge: Icon, 2001.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

Latimer, Dan. Contemporary critical theory. San Diego: Harcourt, Brace, Jovanovich, 1989.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
More sources

Book chapters on the topic "The theory of critical distances"

1

Taylor, David. "Microstructural Parameters in the Theory of Critical Distances." In Materials Science Forum, 23–28. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-469-3.23.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Plekhov, Oleg A., Alena I. Vedernikova, and Anastasiia A. Kostina. "Theory of Critical Distances as a Method of Failure Prediction Under Dynamic Loading." In Advanced Structured Materials, 187–98. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-79325-8_16.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Susmel, Luca. "Eurocode 3’s Standard Curves and Theory of Critical Distances to Estimate Fatigue Lifetime of Steel Weldments." In Advances in Fracture and Damage Mechanics VI, 21–24. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-448-0.21.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Černý, Pavol, Thomas A. Henzinger, and Arjun Radhakrishna. "Simulation Distances." In CONCUR 2010 - Concurrency Theory, 253–68. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-15375-4_18.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Yamashita, Yoichi, Masaharu Shinozaki, Hiroshi Kuroki, and Yusuke Ueda. "Fatigue Life Prediction of Small Notched Ti-6Al-4V Based on The Theory of Critical Distance." In ICAF 2009, Bridging the Gap between Theory and Operational Practice, 685–706. Dordrecht: Springer Netherlands, 2009. http://dx.doi.org/10.1007/978-90-481-2746-7_39.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Deza, Michel Marie, and Elena Deza. "Distances in Probability Theory." In Encyclopedia of Distances, 233–45. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-30958-8_14.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Deza, Michel Marie, and Elena Deza. "Distances in Graph Theory." In Encyclopedia of Distances, 249–78. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-30958-8_15.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Deza, Michel Marie, and Elena Deza. "Distances in Coding Theory." In Encyclopedia of Distances, 279–90. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-30958-8_16.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Deza, Michel Marie, and Elena Deza. "Distances in Probability Theory." In Encyclopedia of Distances, 257–72. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-662-44342-2_14.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Deza, Michel Marie, and Elena Deza. "Distances in Graph Theory." In Encyclopedia of Distances, 275–307. Berlin, Heidelberg: Springer Berlin Heidelberg, 2014. http://dx.doi.org/10.1007/978-3-662-44342-2_15.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "The theory of critical distances"

1

Chattopadhyay, Somnath. "S-N Curves in Pressure Vessel Steels Using Theory of Critical Distances." In ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61592.

Full text
Abstract:
The S-N technology used in the ASME Code and similar design criteria includes both crack initiation and crack propagation phases of fatigue failure. Some of the pressure vessel construction codes have used the simplified fatigue initiation criterion based on stresses calculated at a distance of 0.05 mm from the surface crack. In this work such techniques have been assessed for pressure vessels in light of the theory of critical distances. This method has been used to generate S-N curves for typical materials such as medium carbon steels, nickel chrome steels and stainless steels. Separate techniques have been highlighted for obtaining the number of cycles to nucleate a crack from a free surface, and also the number of cycles to drive the nucleated surface crack to propagate to a length equal to the critical distance parameter related to the process zone. The two estimates on the number of cycles when combined constitute a reasonable estimate of the number of cycles to initiate a crack and form the basis of the S-N design curves. The method requires the material property information on elastic-plastic fracture toughness and short crack propagation characteristics including crack closure effects.
APA, Harvard, Vancouver, ISO, and other styles
2

González, P., S. Cicero, B. Arroyo, and J. A. Álvarez. "Analysis of Environmentally Assisted Cracking in S420 Steel by Using the Theory of Critical Distances." In ASME 2019 Pressure Vessels & Piping Conference. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/pvp2019-93145.

Full text
Abstract:
Abstract The behavior of S420 steel under cathodic polarization in low pH aqueous environment is analyzed following the assumptions of the Theory of Critical Distances. This methodology has been successfully applied in fracture and fatigue analysis, but it has not been employed yet under stress corrosion cracking or hydrogen embrittlement conditions. This work focuses on the problem of environmentally assisted cracking by using the Point Method and the Line Method, both of them belonging to the Theory of Critical Distances. Fracture mechanic tests were carried out, using a slow strain rate machine, at two different solicitation rates (6·10−8 m/s and 6·10−9 m/s). The study is based on an experimental program composed of C(T) specimens with notch radii varying from 0 mm up to 2 mm. Cathodic polarization with a 5 mA/cm2 current has been employed and the aqueous aggressive environment was made using the Pressouyre’s method. The study has been completed with finite elements simulation analysis. The results reveal that the Theory of Critical Distances provides accurate predictions of the environmentally assisted cracking behavior of S420 steel in notched conditions.
APA, Harvard, Vancouver, ISO, and other styles
3

Terekhina, Alena, Anastasiya Kostina, and Oleg Plekhov. "Application of the theory of critical distances for the estimation of fracture under dynamic loading." In PROCEEDINGS OF THE INTERNATIONAL CONFERENCE ON ADVANCED MATERIALS WITH HIERARCHICAL STRUCTURE FOR NEW TECHNOLOGIES AND RELIABLE STRUCTURES 2017 (AMHS’17). Author(s), 2017. http://dx.doi.org/10.1063/1.5013899.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Nakahara, Tetsuya, Yusuke Ueda, and Hiroshi Nakamura. "Development of Life Prediction Method of Turbine Blade Using the Theory of Critical Distance." In ASME Turbo Expo 2012: Turbine Technical Conference and Exposition. American Society of Mechanical Engineers, 2012. http://dx.doi.org/10.1115/gt2012-68742.

Full text
Abstract:
Gas turbine blades mounted dovetail root are subjected to high centrifugal loads and gas forces. This situation causes low cycle fatigue (LCF). Recently, rotating speed and temperature of turbine rotor become higher in order to improve engine performance. To achieve this, it is required to evaluate accurate turbine blade’s LCF life of the contact surface between the blade dovetail root and the disk. However, the estimated blade lives using the peak stress calculated by finite element analysis (FEA) are much shorter than actual life because the stress at contact surface is excessively high. As a result, the blades are designed conservative and the blade’s weight tends to be heavy. Therefore, a more accurate evaluation methodology needs to be established. This study investigates the method to estimate the fatigue strength of dovetail using the theory of critical distance. The theory assumes that fatigue failures would occur due to the representative stress within a specific distance from stress concentration point. Fatigue tests and FEA for the turbine blade dovetail were conducted respectively in this research. The tests were carried out using single crystal nickel-based turbine blades at 600 °C and the fracture lives of dovetail were obtained. FEA was conducted to obtain the stress distributions at dovetail contact surface under testing condition. In this study, the critical distances of the single crystal nickel based alloy were obtained from the notched bar fatigue tests and FEA. Using these results and the theory of critical distance, fatigue lives of dovetail were obtained more accurately.
APA, Harvard, Vancouver, ISO, and other styles
5

Terekhina, A., and O. Plekhov. "Evaluation of quasistatic and dynamic strength of components with stress concentrators based on the theory of critical distances." In MECHANICS, RESOURCE AND DIAGNOSTICS OF MATERIALS AND STRUCTURES (MRDMS-2016): Proceedings of the 10th International Conference on Mechanics, Resource and Diagnostics of Materials and Structures. Author(s), 2016. http://dx.doi.org/10.1063/1.4967144.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

D'yachkov, A., A. Voronina, A. Macula, T. Renz, and V. Rykov. "On critical relative distance of DNA codes for additive stem similarity." In 2010 IEEE International Symposium on Information Theory - ISIT. IEEE, 2010. http://dx.doi.org/10.1109/isit.2010.5513751.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Wang, Hu, Guansong Pang, Chunhua Shen, and Congbo Ma. "Unsupervised Representation Learning by Predicting Random Distances." In Twenty-Ninth International Joint Conference on Artificial Intelligence and Seventeenth Pacific Rim International Conference on Artificial Intelligence {IJCAI-PRICAI-20}. California: International Joint Conferences on Artificial Intelligence Organization, 2020. http://dx.doi.org/10.24963/ijcai.2020/408.

Full text
Abstract:
Deep neural networks have gained great success in a broad range of tasks due to its remarkable capability to learn semantically rich features from high-dimensional data. However, they often require large-scale labelled data to successfully learn such features, which significantly hinders their adaption in unsupervised learning tasks, such as anomaly detection and clustering, and limits their applications to critical domains where obtaining massive labelled data is prohibitively expensive. To enable unsupervised learning on those domains, in this work we propose to learn features without using any labelled data by training neural networks to predict data distances in a randomly projected space. Random mapping is a theoretically proven approach to obtain approximately preserved distances. To well predict these distances, the representation learner is optimised to learn genuine class structures that are implicitly embedded in the randomly projected space. Empirical results on 19 real-world datasets show that our learned representations substantially outperform a few state-of-the-art methods for both anomaly detection and clustering tasks. Code is available at: \url{https://git.io/RDP}
APA, Harvard, Vancouver, ISO, and other styles
8

Dias, Jéssica Nayara, JORGE FERREIRA, and Letícia Silva. "Behavior of the distribution of life in notched components according to TCD (Theory of critical distance)." In 24th ABCM International Congress of Mechanical Engineering. ABCM, 2017. http://dx.doi.org/10.26678/abcm.cobem2017.cob17-1567.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Taylor, David, and Saeid Kasiri. "A Critical Distance Analysis of the Effect of Crack Length on Toughness and Fatigue in Compact Bone." In ASME 2008 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2008. http://dx.doi.org/10.1115/sbc2008-192304.

Full text
Abstract:
The plane strain fracture toughness, KIC, has a constant value for long cracks, but when specimens containing short cracks are tested it is often found that the measured toughness is less than the long-crack value, and tends to decrease with decreasing crack length. A similar effect occurs when measuring the cyclic stress intensity range, ΔK, corresponding to a given rate of crack growth da/dN. Some experimental data are available in the published literature to show that cortical bone displays these short-crack effects for crack lengths of the order of millimeters or less. The hypothesis of the present work was that these effects can be predicted using an approach known as the Theory of Critical Distances. This is the first time that this approach has been used to predict short crack effects in bone.
APA, Harvard, Vancouver, ISO, and other styles
10

Barnett, Ralph L., Susanne A. Glowiak, and Peter J. Poczynok. "Stochastic Theory of Human Slipping." In ASME 2002 International Mechanical Engineering Congress and Exposition. ASMEDC, 2002. http://dx.doi.org/10.1115/imece2002-32450.

Full text
Abstract:
The conventional approach to human slipping is essentially deterministic; it states that no slipping will occur when the average friction coefficient is greater than some critical friction criterion. Under this condition, pedestrians will not slip when they encounter the average friction coefficient. On the other hand, to successfully negotiate a walk of n-steps they must not slip when they encounter the smallest of the n friction coefficients. Consequently, a new slip theory has been formulated as a problem in extreme value statistics. An elegant relationship is obtained among the probability of slipping, the critical friction criterion, the number of steps taken by the walker, and the central measure, scatter, and asymmetry of the distribution of friction coefficients. The new theory reveals the structure of human slipping in a startling way that introduces completely new concepts: the go/no go nature of classical slip predictions is replaced by a probability of slipping; low friction floor/footwear couples may lead to fewer slips than high friction ones; slipping can occur in any case where conventional theory predicts “no slip”; and the number of slips depends on the distance traveled by a pedestrian. Finally, this paper develops the idea that the slipperiness of a real floor must be evaluated for a duty-cycle. Duty-cycles can be represented as frequency histograms when a floor is homogeneous and isotropic.
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "The theory of critical distances"

1

Silverstein, Eva M. de Sitter Space in Non-Critical String Theory. Office of Scientific and Technical Information (OSTI), August 2002. http://dx.doi.org/10.2172/799932.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Kishimoto, Y., T. Tajima, W. Horton, M. J. LeBrun, and J. Y. Kim. Theory of self-organized critical transport in tokamak plasmas. Office of Scientific and Technical Information (OSTI), July 1995. http://dx.doi.org/10.2172/100314.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Berney, Ernest, Naveen Ganesh, Andrew Ward, J. Newman, and John Rushing. Methodology for remote assessment of pavement distresses from point cloud analysis. Engineer Research and Development Center (U.S.), April 2021. http://dx.doi.org/10.21079/11681/40401.

Full text
Abstract:
The ability to remotely assess road and airfield pavement condition is critical to dynamic basing, contingency deployment, convoy entry and sustainment, and post-attack reconnaissance. Current Army processes to evaluate surface condition are time-consuming and require Soldier presence. Recent developments in the area of photogrammetry and light detection and ranging (LiDAR) enable rapid generation of three-dimensional point cloud models of the pavement surface. Point clouds were generated from data collected on a series of asphalt, concrete, and unsurfaced pavements using ground- and aerial-based sensors. ERDC-developed algorithms automatically discretize the pavement surface into cross- and grid-based sections to identify physical surface distresses such as depressions, ruts, and cracks. Depressions can be sized from the point-to-point distances bounding each depression, and surface roughness is determined based on the point heights along a given cross section. Noted distresses are exported to a distress map file containing only the distress points and their locations for later visualization and quality control along with classification and quantification. Further research and automation into point cloud analysis is ongoing with the goal of enabling Soldiers with limited training the capability to rapidly assess pavement surface condition from a remote platform.
APA, Harvard, Vancouver, ISO, and other styles
4

Hewett, J. Black Holes in Many Dimensions at the LHC: Testing Critical String Theory. Office of Scientific and Technical Information (OSTI), March 2005. http://dx.doi.org/10.2172/839919.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Andrabi, Tahir, Benjamin Daniels, and Jishnu Das. Human Capital Accumulation and Disasters: Evidence from the Pakistan Earthquake of 2005. Research on Improving Systems of Education (RISE), May 2020. http://dx.doi.org/10.35489/bsg-risewp_2020/039.

Full text
Abstract:
We trace the effects of a devastating earthquake that occurred in Northern Pakistan in 2005. Using a new dataset from a survey conducted four years after the earthquake, we first show that the distance of the household from the fault line was not correlated with pre-existing household characteristics, while it was strongly predictive of earthquake-related damage and mortality. Through emergency relief aid, households living close to the fault line reported receiving substantial cash compensation that amounted to as much as 150% of their annual household consumption expenditure. Four years after the earthquake, there were no differences in public infrastructure, household or adult outcomes between areas close to and far from the fault line. However, children in their critical first thousand days at the time of the earthquake accumulated large height deficits, with the youngest the most affected. Children aged 3 through 15 at the time of the earthquake did not suffer growth shortfalls, but scored significantly worse on academic tests if they lived close to the fault line. Finally, children whose mothers completed primary education were fully protected against the emergence of a test score gap. We estimate that if these deficits continue to adult life, the affected children could stand to lose 15% of their lifetime earnings. Even when disasters are heavily compensated, human capital accumulation can be critically interrupted, with greater losses for already disadvantaged populations.
APA, Harvard, Vancouver, ISO, and other styles
6

Pace, Cristina. Robert Alexy’s A Theory of Constitutional Rights critical review: key jurisprudential and political questions. DINÂMIA'CET-IUL, 2012. http://dx.doi.org/10.7749/dinamiacet-iul.wp.2012.01.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Zutavern, Fred J., Harold P. Hjalmarson, Verle Howard Bigman, and Richard Joseph Gallegos. Experiments and Computational Theory for Electrical Breakdown in Critical Components: THz Imaging of Electronic Plasmas. Office of Scientific and Technical Information (OSTI), November 2016. http://dx.doi.org/10.2172/1338164.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Núñez Ladevéze, L., T. Vázquez Barrio, and I. Álvarez de Mon Pan de Soraluce. From "deception of the masses" of the critical theory to the "undefined neighborhood" of Bauman. Revista Latina de Comunicación Social, July 2019. http://dx.doi.org/10.4185/rlcs-2019-1374en.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Byron, Amanda. Storytelling as Loving Praxis in Critical Peace Education: A Grounded Theory Study of Postsecondary Social Justice Educators. Portland State University Library, January 2000. http://dx.doi.org/10.15760/etd.245.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Lantz, Paula. The Tenets of Critical Race Theory Have a Long-Standing and Important Role in Population Health Science. Milbank Memorial Fund, July 2021. http://dx.doi.org/10.1599/mqop.2021.0714.

Full text
APA, Harvard, Vancouver, ISO, and other styles
You might also be interested in the extended bibliographies on the topic 'The theory of critical distances' for particular source types:
Journal articles Dissertations / Theses Books
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography