892 resultados para fracture and deformation concepts
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En los últimos años, podemos darnos cuenta de la importancia que tienen las nuevas aplicaciones de vidrio especialmente en edificios turísticos donde el vértigo juega un papel importante en la visita. Sin embargo los sistemas constructivos no tienen un especial interés porque el vidrio laminado está siempre soportado por otro elemento de acero o incluso vidrio en forma de retícula. En la presente tesis voy a desarrollar una nueva solución de elemento autoportante de vidrio de gran tamaño haciendo seguro el uso del elemento para andar en el aire. El sueño de muchos arquitectos ha sido diseñar un edificio completamente transparente y a mí me gustaría contribuir a este sueño empezando a estudiar un forjado de vidrio como elemento estructural horizontal y para ello debemos cumplir requerimientos de seguridad. Uno de los objetivos es lograr un elemento lo más transparente y esbelto posible para el uso de pasarelas en vestíbulos de edificios. Las referencias construidas son bien conocidas, pero por otro lado Universidades europeas estudian continua estudiando el comportamiento del vidrio con diferentes láminas, adhesivos, apilados, insertos, sistemas de laminado, pretensado, pandeo lateral, seguridad post-rotura y muchos más aspectos necesarios. La metodología llevada a cabo en esta tesis ha sido primeramente diseñar un elemento industrial prefabricado horizontal de vidrio teniendo en cuenta todos los conceptos aprendidos en el estado del arte y la investigación para poder predimensionar el elemento. El siguiente paso será verificar el modelo por medio de cálculo analítico, simulación de elementos finitos y ensayos físicos. Para realizar los ensayos hay un paso intermedio teniendo que cambiar la hipótesis de carga uniforme a carga puntal para realizar el ensayo de flexión a 4 puntos normalizado y además cambiar a escala 1:2 para adaptarse al espacio de ensayo y ser viable económicamente. Finalmente compararé los resultados de tensión y deformación obtenidos por los tres métodos para extraer conclusiones. Sin embargo el problema de la seguridad no ha concluido, tendré que demostrar que el sistema es seguro después de que se produzca la rotura y para ello sólo dispongo de los ensayos como medio de demostración. El diseño es el resultado de la evolución de una viga tipo “I”; cuando es pretensada para obtener más resistencia, aparece el problema de pandeo lateral y éste es solucionado con una viga con sección en “T” cuya unión es resuelta con un cajeado longitudinal en la parte inferior del elemento horizontal. Las alas de éste crecen para recoger las cargas superficiales creando a su vez un punto débil en la unión que a su vez se soluciona duplicando la sección “TT” y haciendo trabajar dicho tablero de forma tan óptima como una viga continua. Dicha sección en vidrio como un único elemento pretensado es algo inédito. Además he diseñado unas escuadras metálicas en los extremos de los nervios como apoyo y placa de pretensión, así como una hendidura curva en el centro de los nervios para alojar los tirantes de acero de modo que al pretensar el tirante la placa corrija al menos la deformación por peso propio. Realizados los cambios geométricos de escala y las simplificaciones en el laminado y el adhesivo se programan la extracción de resultados desde 3 estadios diferentes: Sin pretensión y con pretensión de 750 Kg y de 1000Kg en cada nervio. Por cada estadio y por cada uno de los métodos, cálculo, simulación y ensayos, se extraen los datos de deformación y tensión en el punto medio de un nervio con el objetivo de hacer una comparación de resultados para obtener unas conclusiones, siempre en el campo de la elasticidad. Posteriormente incrementaré la carga hasta el momento de la rotura de la placa y después hasta el colapso teniendo en cuenta el tiempo y demostrando una rotura segura. El vidrio no tendrá un comportamiento plástico pero habrá sido controlado su comportamiento frágil manteniendo una carga y una deformación aceptable. ABSTRACT Over the past few years we have realized the importance of the new technologies regarding the application of glass in new buildings, especially those touristic places were the views and the heights are the reason of the visit. However, the construction systems of these glass platforms are not usually as interesting, because the laminated glass is always held by another steel substructure or even a grid-formed glass element. Throughout this thesis I am going to develop a new solution of a self-bearing element with big dimensions made out of glass, ensuring a safe solution to use as an element to walk on the air. The dream of many architects has been to create a building completely transparent, and I would like to contribute to this idea by making a glass slab as a horizontal structural element, for which we have to meet the security requirements. One of the goals is to achieve an element as transparent and slim as possible for the use in walkways of building lobbies. The glass buildings references are well known, but on the other hand the European Universities study the behaviour of the glass with different interlayers, adhesives, laminating systems, stacking, prestressed, buckling, safety, breakage and post-breakage capacity; and many other necessary aspects. The methodology followed in this thesis has been to first create a horizontal industrial prefabricated horizontal element of glass, taking into account all the concepts learned in the state of art and the investigation to be able to predimension this element. The next step will be to verify this model with an analytic calculus, a finite element modelling simulation and physical tests. To fulfil these tests there is an intermediate step, having to change the load hypothesis from a punctual one to make the test with a four points normalized deflexion, and also the scale of the sample was changed to 1:2 to adapt to the space of the test and make it economically possible. Finally, the results of tension and deformation obtained from the three methods have been compared to make the conclusions. However, the problem with safety has not concluded yet, for I will have to demonstrate that this system is safe even after its breakage, for which I can only use physical tests as a way of demonstration. The design is the result of the evolution of a typical “I” beam, which when it is prestressed to achieve more resistance, the effect of buckling overcomes, and this is solved with a “T” shaped beam, where the union is solved with a longitudinal groove on the inferior part of the horizontal element. The boards of this beam grow to cover the superficial loads, creating at the same time a weak point, which is solved by duplicating the section “TT” and therefore making this board work as optimal as a continuous beam. This glass section as a single prestressed element is unique. After the final design of the “π” glass plate was obtained and the composition of the laminated glass and interlayers has been predimensioned, the last connection elements must be contemplated. I have also designed a square steel shoe at the end of the beams, which will be the base and the prestressed board, as well as a curved slot in the centre of the nerves to accommodate the steel braces so that when this brace prestresses the board, at least the deformation due to its self-weight will be amended. Once I made the geometric changes of the scale and the simplifications on the laminating and the adhesive, the extraction on results overcomes from three different stages: without any pretension, with a pretension of 750 kg and with a pretension of 1000 kg on each rib. For each stage and for each one of the methods, calculus, simulation and tests, the deformation datum were extracted to obtain the conclusions, always in the field of the elasticity. Afterwards, I will increase the load until the moment of breakage of this board, and then until the collapse of the element, taking into account the time spent and demonstrating a safe breakage. The glass will not have a plastic behaviour, but its brittle behaviour has been controlled, keeping an acceptable load and deflection.
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Mathematical chaos and related concepts are used to explain and resolve issues ranging from voting paradoxes to the apportioning of congressional seats.
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This study involves a qualitative analysis of a doctoral-level psychology trainee's first-hand account of sexual attraction and boundary violations that occurred in her clinical supervision and psychotherapy. Concepts of power, gender, social performance theory, and relational framing are applied to two case examples, illustrating the differing demands on a trainee when her relationships were sexualized in two distinct professional contexts. Ramifications of supervisory exploitation and the impact of such an experience on a trainee's professional development are discussed. Recommendations are provided for improving psychology training programs' prevention and response efforts.
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In the past years, an important volume of research in Natural Language Processing has concentrated on the development of automatic systems to deal with affect in text. The different approaches considered dealt mostly with explicit expressions of emotion, at word level. Nevertheless, expressions of emotion are often implicit, inferrable from situations that have an affective meaning. Dealing with this phenomenon requires automatic systems to have “knowledge” on the situation, and the concepts it describes and their interaction, to be able to “judge” it, in the same manner as a person would. This necessity motivated us to develop the EmotiNet knowledge base — a resource for the detection of emotion from text based on commonsense knowledge on concepts, their interaction and their affective consequence. In this article, we briefly present the process undergone to build EmotiNet and subsequently propose methods to extend the knowledge it contains. We further on analyse the performance of implicit affect detection using this resource. We compare the results obtained with EmotiNet to the use of alternative methods for affect detection. Following the evaluations, we conclude that the structure and content of EmotiNet are appropriate to address the automatic treatment of implicitly expressed affect, that the knowledge it contains can be easily extended and that overall, methods employing EmotiNet obtain better results than traditional emotion detection approaches.
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A wide variety of different socially motivated organisations perform exceptional feats in alleviating societal ills using creativity and entrepreneurial spirit in their quest to scale their social impact. Their focus is seldom limited to one specific region – instead they strive to benefit the largest possible number of people, thereby often transcending national borders. After all, societal issues usually don’t stop at a countries’ borders – why then should good ideas and impactful concepts aimed at solving these issues? For many socially motivated organisations, the goal of disseminating their social impact remains a solemn wish due to lacking experience and know-how of how to plan and conduct systematic scaling.
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The aim of the conference is to bring together academia and industry to discuss the safety of food packaging as well as the development of new food packaging materials, including active, intelligent and nano concepts. Bio-based materials will be also discussed due to be a growing area of food packaging. Topics: Food Safety & Quality (Physical and chemical hazards: measurement and assessment; Biological hazards: risk and prevention; Mathematical modelling of risk assessment; Evaluation of food spoilage, food quality and shelf life; Food packaging laws and regulations; Food package interactions: migration measurement methods, models and food safety risk assessment; Food Packaging innovation (Active and intelligent packaging; Nano-packaging; New packaging materials and material development; Bio based and edible packaging; Food package testing; Sustainable food contact materials; Recycling and Life Cycle Assessment).
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From the upper 300 m of CRP-2/2A, twenty-six samples of diamicts and deformation structures have been thin sectioned. These have been analysed for texture, structure, diagenesis and plasmic fabric. The combination of certain microstructures (e.g. turbate and linear) and plasmic fabric development is indicative of grounded ice. Clear evidence for two grounded ice events (three samples) was found in the upper Oligocene part of the core. The interpretation of ten more samples is less certain, but as for CRP-1, is taken to point to grounded ice as well. There is a strong correlation between these indications for grounded ice and the basal part of cycles in the sequence stratigraphy.
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Ocean Drilling Program Legs 170 and 205 offshore Costa Rica provide structural observations which support a new model for the geometry and deformation response to the seismic cycle of the frontal sedimentary prism and decollement. The model is based on drillcore, thin section, and electron microscope observations. The decollement damage zone is a few tens of meters in width, it develops mainly within the frontal prism. A clear cm-thick fault core is observed 1.6 km from the trench. The lower boundary of the fault core is coincident with the lithological boundary between the frontal prism and the hemipelagic and pelagic sediment of the Cocos plate. Breccia clast distributions in the upper portion of the decollement damage zone were studied through fractal analysis. This analysis shows that the fractal dimension changes with brecciated fragment size, implying that deformation was not accommodated by self-similar fracturing. A higher fractal dimensionality correlates with smaller particle size, which indicates that different or additional grain-size reduction processes operated during shearing. The co-existence of two distinct fracturing processes is also confirmed by microscopic analysis in which extension fracturing in the upper part of the damage zone farthest from the fault core is frequent, while both extension and shear fracturing occur approaching the fault core. The coexistence of extensional and shear fracturing seems to be best explained by fluid pressure variations in response to variations of the compressional regime during the seismic cycle. During the co-seismic event, sub-horizontal compression and fluid pressure increase, triggering shear fracturing and fluid expulsion. Fractures migrate upward with fluids, contributing to the asymmetric shape of the decollement, while slip propagates. In the inter-seismic interval the frontal prismrelaxes and fluid pressure drops. The frontal prismgoes into diffuse extension during the intervalwhen plate convergence is accommodated by creep along the ductile fault core. The fault core is typically a barrier to deformation, which is explained by its weak, but impermeable, nature. The localized development of a damage zone beneath the fault core is characterized by shear fracturing that appears as the result of local strengthening of the detachment.
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Thesis (Ph.D.)--University of Washington, 2016-06
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Thesis (D.M.A.)--University of Washington, 2016-06
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This research explores gestures used in the context of activities in the workplace and in everyday life in order to understand requirements and devise concepts for the design of gestural information appliances. A collaborative method of video interaction analysis devised to suit design explorations, the Video Card Game, was used to capture and analyse how gesture is used in the context of six different domains: the dentist's office; PDA and mobile phone use; the experimental biologist's laboratory; a city ferry service; a video cassette player repair shop; and a factory flowmeter assembly station. Findings are presented in the form of gestural themes, derived from the tradition of qualitative analysis but bearing some similarity to Alexandrian patterns. Implications for the design of gestural devices are discussed.
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A textural and microstructural study of a variety of zinc sulfide-containing ores has been undertaken, and the possible depositional and deformational controls of textural and microstructural development considered. Samples for the study were taken from both deformed and undeformed zinc ores of the Central U.S. Appalachians, and deformed zinc ores of the English Pennines. A variety of mineralogical techniques were employed, including transmitted and reflected light microscopy of etched and unetched material, transmission electron microscopy and electron microprobe analysis. For the Pennine zinc sulfides, spectroscopic, x-ray diffraction and fluid inclusion studies were also undertaken. Optical and electron optical examination of the Appalachian material confirmed the suitability of zinc sulfide for detailed study with such techniques. Growth and deformation-related microstructures could be distinguished from specimen-preparation induced artifacts. A deformationally-mduced lamelliform optical anisotropy is seen to be developed in areas hosting a dense planar microstructure of {111} twin- and slip-planes. The Pennine zinc sulfide texturally records a changing depositional environment. Thus, for example, delicately growth- zoned crystals are truncated and cross-cut by solution disconformities. Fluid inclusion studies indicate a highly saline (20-25 wt. % equiv. NaCl), low temperature (100-150°C.) fluid. Texturally, two varieties of zinc sulfide can be recognised; a widely developed, iron- banded variety, and a paragenetically early variety, banded due to horizons rich in crystal defects and microscopic inclusions. The zinc sulfide takes the form of a disordered 3C-polytype, with much of the disorder being deformational in origin. Twin- and slip-plane fabrics are developed . A deformation-related optical anisotropy is seen to overprint growth-related anisotropy, along with cuprian alteration of certain {111} deformation planes.
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Supply Chain Risk Management (SCRM) has become a popular area of research and study in recent years. This can be highlighted by the number of peer reviewed articles that have appeared in academic literature. This coupled with the realisation by companies that SCRM strategies are required to mitigate the risks that they face, makes for challenging research questions in the field of risk management. The challenge that companies face today is not only to identify the types of risks that they face, but also to assess the indicators of risk that face them. This will allow them to mitigate that risk before any disruption to the supply chain occurs. The use of social network theory can aid in the identification of disruption risk. This thesis proposes the combination of social networks, behavioural risk indicators and information management, to uniquely identify disruption risk. The propositions that were developed from the literature review and exploratory case study in the aerospace OEM, in this thesis are:- By improving information flows, through the use of social networks, we can identify supply chain disruption risk. - The management of information to identify supply chain disruption risk can be explored using push and pull concepts. The propositions were further explored through four focus group sessions, two within the OEM and two within an academic setting. The literature review conducted by the researcher did not find any studies that have evaluated supply chain disruption risk management in terms of social network analysis or information management studies. The evaluation of SCRM using these methods is thought to be a unique way of understanding the issues in SCRM that practitioners face today in the aerospace industry.
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Introduction - Monocytes, with 3 different subsets, are implicated in the initiation and progression of the atherosclerotic plaque contributing to plaque instability and rupture. Mon1 are the “classical” monocytes with inflammatory action, whilst Mon3 are considered reparative with fibroblast deposition ability. The function of the newly described Mon2 subset is yet to be fully described. In PCI era, fewer patients have globally reduced left ventricular ejection fraction post infarction, hence the importance of studying regional wall motion abnormalities and deformation at segmental levels using longitudinal strain. Little is known of the role for the 3 monocyte subpopulations in determining global strain in ST elevation myocardial infarction patients (STEMI). Conclusion In patients with normal or mildly impaired EF post infarction, higher counts of Mon1 and Mon2 are correlated with GLS within 7 days and at 6 months of remodelling post infarction. Adverse clinical outcomes in patients with reduced convalescent GLS were predicted with Mon1 and Mon2 suggestive of an inflammatory role for the newly identified Mon2 subpopulation. These results imply an important role for monocytes in myocardial healing when assessed by subclinical ventricular function indices. Methodology - STEMI patients (n = 101, mean age 64 ± 13 years; 69% male) treated with percutaneous revascularisation were recruited within 24 h post-infarction. Peripheral blood monocyte subpopulations were enumerated and characterised using flow cytometry after staining for CD14, CD16 and CCR2. Phenotypically, monocyte subpopulations are defined as: CD14++CD16-CCR2+ (Mon1), CD14++CD16+CCR2+ (Mon2) and CD14+CD16++CCR2- (Mon3). Phagocytic activity of monocytes was measured using flow cytometry and Ecoli commercial kit. Transthoracic 2D echocardiography was performed within 7 days and at 6 months post infarct to assess global longitudinal strain (GLS) via speckle tracking. MACE was defined as recurrent acute coronary syndrome and death. Results - STEMI patients with EF ≥50% by Simpson’s biplane (n = 52) had GLS assessed. Using multivariate regression analysis higher counts of Mon1 and Mon 2 and phagocytic activity of Mon2 were significantly associated with GLS (after adjusting for age, time to hospital presentation, and peak troponin levels) (Table 1). At 6 months, the convalescent GLS remained associated with higher counts of Mon1, Mon 2. At one year follow up, using multivariate Cox regression analysis, Mon1 and Mon2 counts were an independent predictor of MACE in patients with a reduced GLS (n = 21)
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This is the second of two linked papers exploring decision making in nursing. The first paper, 'Classifying clinical decision making: a unifying approach' investigated difficulties with applying a range of decision-making theories to nursing practice. This is due to the diversity of terminology and theoretical concepts used, which militate against nurses being able to compare the outcomes of decisions analysed within different frameworks. It is therefore problematic for nurses to assess how good their decisions are, and where improvements can be made. However, despite the range of nomenclature, it was argued that there are underlying similarities between all theories of decision processes and that these should be exposed through integration within a single explanatory framework. A proposed solution was to use a general model of psychological classification to clarify and compare terms, concepts and processes identified across the different theories. The unifying framework of classification was described and this paper operationalizes it to demonstrate how different approaches to clinical decision making can be re-interpreted as classification behaviour. Particular attention is focused on classification in nursing, and on re-evaluating heuristic reasoning, which has been particularly prone to theoretical and terminological confusion. Demonstrating similarities in how different disciplines make decisions should promote improved multidisciplinary collaboration and a weakening of clinical elitism, thereby enhancing organizational effectiveness in health care and nurses' professional status. This is particularly important as nurses' roles continue to expand to embrace elements of managerial, medical and therapeutic work. Analysing nurses' decisions as classification behaviour will also enhance clinical effectiveness, and assist in making nurses' expertise more visible. In addition, the classification framework explodes the myth that intuition, traditionally associated with nurses' decision making, is less rational and scientific than other approaches.