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A influência do modelo de negócios no sucesso do projeto em organizações / The influence of the business model in organizations' project successGonçalves, Marcelo Luiz do Amaral 15 February 2017 (has links)
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Previous issue date: 2017-02-15 / In a wide range of activities, companies have been using the Business Model to represent the organization's strategy in delivering value and meeting the needs of its clients and segments with organizational efficiency and competitive differential. The business model presents itself as a very useful conceptual tool for capturing, sharing and creating a common view of the organization model. The projects are prominent in the strategic issues, because through them it is possible to materialize the planned strategic objectives and described in the Business Model of the company. The evaluation of project success can be accomplished by considering short and long-term objectives, uncertainties associated with the market, and technologies that may affect expectations about project success. This research analyzed the influence of the configuration of the business model in the project success in national and international companies from different fields of activity. In this study, each of the dimensions that constitute the Business Model was identified, as well as the dimensions of the Project Success. Additionally, was verified the contribution of the Business Model configuration in the overall configuration of the Business Model and the contribution of the Project Success dimensions in the overall success of the Project.
This research is of an applied nature, characterized as confirmatory-descriptive and the data were obtained through a survey, using as a research instrument a structured questionnaire for data collection. The questionnaire was sent to a universe composed of professionals from various fields of activity, with leadership positions and who have already participated in projects, providing a number of 181 valid answers. The quantitative analysis was used to study the data collected in the research, using the Structural Equation Modeling (SEM) as the method and the Partial Least Square (PLS-SEM) as a technique for analyzing the data. The results showed that the configuration of the business model has a positive influence to the project success, explaining 46% of the effects on the success of projects developed in organizations of several branches of activities in several countries. As a contribution to professional practice, was proposed the Business Model´s Components Evaluation Model. This model aims to assess the maturity of each components that constitutes a Business Model, helping managers to diagnose which components need action to improve the maturity of Business Models in their organizations. / Nos mais diversos ramos de atividades, as empresas vêm utilizando o Modelo de Negócios para representar a estratégia da organização na entrega de valor e atender as necessidades de seus clientes e segmentos com eficiência organizacional e diferencial competitivo. O modelo de negócios apresenta-se como uma ferramenta conceitual muito útil para capturar, compartilhar e criar uma visão comum do modelo da organização. Os projetos são destaques nas questões estratégicas, pois através deles é possível materializar os objetivos estratégicos planejados e descritos no Modelo de Negócios da empresa. A avaliação do sucesso do projeto pode ser realizada considerando os objetivos de curtos e longos prazos, as incertezas associadas ao mercado e as tecnologias que podem afetar as expectativas em torno do sucesso do projeto. Esta pesquisa analisou a influência do modelo de negócios no sucesso do projeto em empresas nacionais e internacionais de diversos setores de atividades. Neste estudo, foi identificado cada uma das dimensões que constitui o Modelo de Negócios, bem como as dimensões do Sucesso do Projeto. Adicionalmente, foi verificada a contribuição da configuração do Modelo de Negócios no sucesso global do projeto e em cada uma das dimensões que compõe o sucesso do projeto. Esta pesquisa é de natureza aplicada, caracterizada como confirmatória-descritiva e os dados foram obtidas por meio de levantamento (Survey), utilizando como instrumento de pesquisa um questionário estruturado para a coleta dos dados. O questionário foi encaminhado a um universo composto por profissionais de vários ramos de atividade, com cargos de liderança e que já participaram de projetos, proporcionando um número de 181 respostas válidas. Foi utilizada a análise quantitativa para estudar os dados coletados na pesquisa, tendo a Modelagem de Equações Estruturais (MEE) como método e o Partial Least Square - Structural Equation Modeling (PLS-SEM) como técnica para analisar os dados. Os resultados demonstraram que a configuração do modelo de negócios influencia positivamente o sucesso do projeto, explicando 46% dos efeitos no sucesso do projeto desenvolvidos em organizações de diversos ramos de atividades em diversos países. Como contribuição para a prática profissional foi proposto o Modelo de Avaliação dos Componentes do Modelo de Negócios. Este modelo tem como objetivo avaliar a maturidade de cada um dos componentes que constituem um Modelo de Negócios, auxiliando os gestores a diagnosticar quais componentes necessitam de ações para melhorar o nível de maturidade dos Modelos de Negócios em suas organizações.
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Criptografia adaptativa em redes de sensores visuais sem fioGon?alves, Danilo de Oliveira 19 August 2015 (has links)
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Previous issue date: 2015-08-19 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Recently Wireless Sensor Networks have gained attention of researchers and industry around the world, such that many projects and solutions have been developed for various scenarios and applications. Such networks are formed by small sensor nodes with low processing power, few memory and few energy. Thus, resources are scarce, particularly energy, where, in most cases these nodes are powered by batteries, which is a crucial point in the network design. A kind of sensor network in which camera-enabled sensors are inserted are call Wireless Visual Sensor Networks. Because of this, these networks become able to recover large quantities of environment information which may to be interesting for several applications. However, in general, sensor networks are very vulnerable due to the nature of the communication and due also to the sensor nodes are, sometimes, in remote, hostile and hard to reach areas. Moreover, the sensor nodes are potentially inexpensive devices that can be easily purchased or designed by others to attack the network. So to mitigate these vulnerabilities, research in security area for such networks are required. However, traditional security mechanisms lead to very overhead of computing and communication can compromise the network performance when they are adopted. Thinking about it, this master's thesis aims to propose a new paradigm to ensure security for wireless visual sensor networks, being presented through a theoretical mathematical model to perform differentiation of areas in the monitoring environment to then considering the particularities of the application monitoring to provide security at different levels. Called Adaptive Encryption, this theoretical model can be used for various applications requiring different security assurances for different network locations, implying providing security at acceptable levels while consuming less network resources, above all energy. / Recentemente as Redes de Sensores Sem Fio t?m ganhado a aten??o de pesquisadores, da ind?stria e do meio acad?mico ao redor do mundo todo, de modo que muitos projetos e solu??es t?m sido desenvolvidas para diversos cen?rios e aplica??es. Essas redes s?o formadas por pequenos n?s sensores com pouco poder de processamento, mem?ria e energia. Sendo assim, os recursos s?o bastante escassos, principalmente energia, onde, na maioria das vezes estes n?s s?o alimentados por baterias, sendo este um ponto crucial no projeto da rede. Um tipo de rede de sensores em que os n?s possuem c?meras de v?deo embutidas s?o chamadas de Redes de Sensores Visuais Sem Fio. Devido a isso, tais redes se tornam capazes de recuperar grandes quantidades de informa??es do ambiente o que pode ser interessante para diversas aplica??es. Todavia, de forma geral, as redes de sensores s?o muito vulner?veis devido a natureza da comunica??o e devido tamb?m aos n?s sensores estarem, algumas vezes, em locais remotos, hostis e de dif?cil acesso. Al?m disso, os n?s sensores s?o dispositivos potencialmente baratos que podem ser facilmente adquiridos ou projetados por terceiros a fim de atacar a rede. Ent?o, visando atenuar essas vulnerabilidades, pesquisas na ?rea de seguran?a para tais redes s?o necess?rias. Contudo, os mecanismos de seguran?a tradicionais geram muito sobrecarga de computa??o e comunica??o podendo comprometer o desempenho da rede quando s?o adotados. Pensando nisso, este trabalho de mestrado tem como objetivo propor um novo paradigma para garantir seguran?a para redes de sensores visuais sem fio, sendo apresentado atrav?s um modelo matem?tico te?rico para realizar diferencia??o de ?reas no ambiente de monitoramento para, ent?o, considerando as particularidades da aplica??o de monitoramento, prover seguran?a em diferentes n?veis. Chamado de Criptografia Adaptativa, este modelo te?rico pode ser utilizado por diversas aplica??es que necessitem de garantias de seguran?a diferenciadas para diferentes locais da rede, o que implica em prover seguran?a em n?veis aceit?veis consumindo menos recursos da rede, principalmente energia.
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Att dela eller inte dela, det är frågan : En undersökning om olika faktorers påverkan på attityd till datainsamling på FacebookIsraelsson, Johan, Edin, Olof January 2020 (has links)
Sweden’s Facebook users produce large amounts of data on a daily basis by sharing their personal data with the platform despite being unaware of what or who the information is used for or by. The reason for this behavior is barely touched in previous research, therefore this quantitative study’s aim is to investigate factors influencing the attitude Facebook users in Sweden have towards sharing data. Beyond this the study also aims to investigate if there’s any difference in factors affecting the attitude between a generation which has grown up surrounded by technology and a generation without the same presence of technology in their upbringing. The study uses a modified version of Technology Acceptance Model (TAM) created by inspiration from previous research by related research. The constructs Previous privacy invasion, Awareness, Perceived risk and Social influence were added to the original TAM and used as a theoretical model for the study. 189 responses were gathered through an online-survey. The answers were analyzed with the multivariate analysis method Partial Least Squares Structural Equation Modeling (PLS-SEM). The method was used to evaluate the hypothesis in the modified model and in turn to answer the research questions posed by the study. After the results shows that the attitude towards sharing data on Facebook's services is affected by perceived risk, social influences from others as well as the useability and perceived ease of use. Furthermore the results show that there are different factors affecting the attitude towards sharing data on Facebook's services among people that have grown up with technology and those that haven't. None of the significant factors in the model were the same for the compared generation. The older generation’s attitude towards sharing data was affected by social influences and perceived ease of use and the younger generation was affected by useability. / Facebooks användare i Sverige genererar stora mängder data varje dag genom att dela med sig av information till plattformen. Användarna delar med sig av denna information trots att många av dem inte vet vad den används till eller vilka som kan ta del av den. Om det finns en eller flera specifika anledningar till varför användarna trots detta fortsätter att använda och således dela information på Facebooks tjänster är okänt. Denna kvantitativa studie har som syfte att undersöka vilka faktorer som påverkar Facebook-användares attityd till att dela information. Studien syftar även till att undersöka om det finns någon skillnad i vad som påverkar attityden hos en generation uppvuxen med teknologi och en äldre generation som inte vuxit upp med samma närvaro av teknologi. Studien använder en version av Technology Acceptance Model (TAM) som modifierats med inspiration hämtad från tidigare forskning inom ämnesområdet för attityd och beteende relaterat till informationssytem. Konstrukten Tidigare integritetsintrång, Kännedom, Upplevd oro och Socialt inflytande har adderats till TAM:s teoretiska grund. i studien används en undersökningsstrategi där 189 svar samlades in från respondenter via en enkätundersökning. Svaren analyserades med multivariatanalysmetoden Partial Least Squares Structural Equation Modeling (PLS-SEM) för att undersöka hypoteserna från den modifierade TAM samt svara på forskningsfrågorna. När samtliga svar från studien analyserats visade resultatet att attityd till datainsamling påverkas av upplevd oro, socialt inflytande från andra samt det sociala mediets nytta och användbarhet. Dessutom visade resultatet att det finns olika faktorer som påverkar attityden hos den yngre och den äldre gruppen. I studien var ingen av de faktorer som var signifikanta för den äldre gruppen signifikanta för den yngre gruppen och vice versa. För den äldre gruppen var socialt inflytande och nytta faktorer som påverkade deras attityd till datainsamling på Facebooks tjänster och för den yngre var den upplevda användbarheten något som påverkade deras attityd till datainsamling.
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Nanoscale Material Characterization of Silicon Nanowires for Application in Reconfigurable Nanowire TransistorsBukovsky, Sayanti 26 July 2021 (has links)
Silicon Nanowire based Reconfigurable Field Effect Transistor (SiNW RFET) presents a solution to increase the system functionality beyond the limits of classical CMOS scaling in More-than-Moore era of semiconductor technology. They are not only spatially reconfigurable, i.e., the source and the drain can be interchangeable in design, but in such devices one can also control the primary charge carrier by controlling the voltage in the control gate. The two key morphological factors controlling reconfigurability are the structure and composition of the Schottky junctions, which serve as the location for Program and Control gates and radial strain induced by the self-limiting oxidation, which influences the carrier mobility resulting in symmetric p and n characteristic curves of an RFET. Despite its potential, in-depth nanoscale studies on the structural and compositional characterization of the key features controlling the reconfigurability are limited and thereby presents as a novel area of research.
In this study, the composition and morphology of the Schottky junction and the radial strain profile due to self-limiting oxidation were studied using advanced imaging and sample preparation techniques like Transmission Electron Microscope (TEM) and Scanning Electron Microscope (SEM) imaging alongside with precise sample preparation methods like Focused Ion Beam (FIB) liftout techniques.
For analysis of radial strain in nanowires that underwent self-limiting oxidation, a TEM lamella was taken of a cross-section of the NW. The lamella was kept at 200 nm thickness to preserve the strain state of the nanowire cross-section.
It was observed that nanowires undergoing such oxidation have an omega (Ω) shaped oxide shell where the shell was discontinued at the spot where the nanowire was touching the substrate. Fast Fourier transform of the high-resolution image of such a NW crossection was used to calculate the strain profile.
The strain is also found to be not radially uniform for such Ω shaped oxide shells. The strain profile shows a local maxima near the nanowire base where it touches the substrate then a minima approximately at the geometric center followed by the maximum strain at the area adjacent to the oxide shell thereby showing a sinusoidal profile. Theoretical simulations performed by Dr. Tim Baldauf further verified the nature of the sinusoidal strain that was observed experimentally. Similar simulations were done for different omega shell shapes, which yielded strain plots of similar sinusoidal strain plots, with the local maxima depending on the level of encapsulation of the NW by the shell.
In the characterization of the Schottky junction, a TEM lamella was taken along the longitudinal direction of a nanowire, which was silicidized from both ends, similar to ones used in SiNW RFET devices. High resolution TEM micrographs and EDX (Energy dispersive X-Ray Spectroscopy) in the TEM along the Schottky junction showed a Ni rich phase and pure Si on either side of the junction. This participating phase was identified as NiSi2. However, the transition between the phases shows a gradient and in-situ experiments were designed to verify the sharpness of the junction.
In in-situ silicidation experiments, Si nanowires with a thin native oxide shell were distributed on an electron transparent surface and were partially covered with Ni islands by shadow sputtering. The whole setup was then heated in a heating stage of a TEM and the Ni was allowed to disperse within the Si nanowires forming NiSi2. HRTEM (High Resolution TEM), EDX and EELS (Electron Energy Loss Spectroscopy) studies were performed on the silicidized samples for further ex-situ analysis.
During the in-situ experiment, it was observed that Ni-phase interface is atomistically sharp and seldom progresses perpendicularly to the nanowire’s direction but through the closed packed planes of the NW. The interface velocity at different temperatures was used to calculate the activation energy of the silicidation process. The value of the activation energy indicates the Ni undergoing volume diffusion through the Ni-rich phase. The velocity of the interface was observed to be much higher in nanowires with smaller diameters than those with higher diameters, further proving the hypothesis.
During the in-situ experiments, in around 10% of nanowires that underwent complete silicidation and held isothermally, the crystalline silicide phase was observed to partially or fully diffuse out of the nanowire core, leaving only a thin shell of Silicon oxide forming ultra-thin walled SiO2 nanotubes (NT).
The onset and the time required for completion of the process varies in the nanowires depending on size of the nanowire, the distance and contact to the nearest Ni islands and presence of defects such as kinks and twists within the nanowire.
In order to study the dynamics of the process, the velocity of the receding front was calculated for nanowires of two different diameters. They are found to be identical, indicating the volume flow rate of the process is directly proportional to the cross-sectional area. The voids were formed by the reduced diffusivity of Ni in Ni2Si phase in comparison to phases with lower percent of Ni. This indicates that the reason behind the phenomenon is coalition of Kirkendall voids and thus dependent on volume diffusion.
From this study, it can be concluded that the extent of self-limiting oxidation and shape of the shell can influence the radial strain state. This can be used to manipulate the strain to tailor the electron and hole transfer characteristics within the RFET. A variety of factors including temperature, time, orientation and radius of the nanowires has been studied with respect to silicidation of a SiNW. The calculated activation energy can be used for precise process control over the location and morphology of Schottky junction. Although not directly related to SiNW RFET devices, the self-assembly of ultra-thin-walled SiO2 NT is a novel research area in itself, the findings of which can be applied in to design novel electronics and sensors.:TABLE OF CONTENTS
Preface
List of Abbreviations
CHAPTER 1: Introduction and Motivation
1.1 Definition and History
1.2 Synthesis Routes
1.3 Properties and Applications
1.4 Nanoscale Electronics and Role of Si Nws
1.4.1
1.4.2 SiNW Reconfigurable Field Effect Transistor
1.5 Introduction to The Topic of The Thesis
1.6 Outline of The Thesis
CHAPTER 2: Physical Basics and Previous Research: A Short Summary
2.1 Strain Measurement and Effects of Strain on on Nanoelectronics
2.1.1 Strain Analysis in Planar CMOS Structures
2.2 Silicidation and Schottky Junction
2.2.1 In-situ Silicidation
2.2.2 Silicon oxide nanotubes
CHAPTER 3: Background of Instruments and Experimental Set-up
3.1 Scanning Electron Microscope
3.2 Transmission Electron Microscope
3.2.1 Imaging Techniques
3.2.2 TEM sample preparation
3.3 Focused Ion Beam
CHAPTER 4: Strain in Nanowire
4.1 Goal of This Study
4.2 Strain in SiNW RFET Devices
4.3 Strain Analysis in SiNW Cross-section
4.3.1 Sample Preparation
4.3.2 Experimental Process
4.3.3 Results and Discussion
4.4 Conclusions
CHAPTER 5: Schottky Junction
5.1 Crystallographic Data on Nickel Silicides
5.2 Formation of Silicides in 2-D Structures
5.2.1 Sample History
5.2.2 Sample Preparation
5.2.3 Results and Discussion
5.3 Formation of Silicides in 1-D Structures: Schottky Junction in NWs
5.3.1 Sample History
5.3.2 Sample Preparation
5.3.3 Results and Discussion
5.3.4 Shortcomings of The Lift-out Technique
5.4 In-situ Silicidation
5.4.1 Motivation
5.4.2 Sample Preparation
5.4.3 Experimental Procedure
5.4.4 Results and Discussions
5.4.5 Shortcoming of The Experiment
5.5 Self-assembling SiO2 Nanotubes
5.5.1 Sample Preparation
5.5.2 Experimental Process
5.5.3 Results and Discussion .
5.5.4 Post In-situ Experiment TEM Analysis
5.5.5 Conclusions
CHAPTER 6: Conclusions and Outlook
6.1 Strain Analysis
6.2 Schottky Junction Studies
Bibliography
Acknowledgements
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Povrchová analýza nanokompozitu xGnP/PEI / Surface analysis of xGnP/PEI nanocompositeČervenka, Jiří January 2012 (has links)
Tato Diplomová práce se zabývá povrchovou analýzou nanokompozitní folie polyetherimidu (PEI) vyztuženého exfoliovanými grafitickými nanodestičkami (xGnP). Analyzovány byly take vzorky nevyztužené PEI folie a samostatné nanodestičky. Vzorky nanokompozitu a PEI folie byly plazmaticky leptány s využitím argonového plazmatu po dobu 1, 3 a 10 hod. Skenovací elektronová mikroskopie (SEM) byla použita pro charakterizaci samostatných nanodestiček rozptýlených na křemíkovém substrátu, původních či leptaných vzorků PEI folie a nanokompozitu. Nanodestičky byly identifikovány při povrchu leptané nanokompozitní folie. Mikroskopie atomárních sil (AFM) byla použita pro zobrazení povrchové topografie separovaných nanodestiček a odkrytých destiček při povrchu leptaného kompozitu. Povrchová drsnost (střední kvadratická hodnota, vzdálenost nejnižšího a nejvyššího bodu) leptaného nanokompozitu narůstala s prodlužující se dobou leptání. Akustická mikroskopie atomárních sil (AFAM) byla použita pro charakterizaci elastické anizotropie leptaných kompozitních vzorků. Nanoindentační měření umožnila charakterizaci lokálních mechanických vlastností PEI a nanokompozitních folií.
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sLORETA-basierte Untersuchung niederamplitudiger Aktivität im Ruhe-EEG in Abhängigkeit vom Vorhandensein langsamer Augenbewegungen (SEM)Jödicke, Johannes 07 July 2014 (has links)
Im unter Ruhebedingungen abgeleiteten Elektroenzephalogramm (Ruhe-EEG) können Episoden niedergespannter EEG-Aktivität sowohl mit Schläfrigkeit, als auch mit geistiger Aktivität assoziiert sein. Aus diesem Grunde stellt niedergespannte EEG-Aktivität eine potentielle Fehlerquelle bei der Interpretation des Ruhe-EEGs dar. Wird niedergespannte EEG-Aktivität jedoch von für das Einschlafen charakteristischen, langsamen Augenbewegungen (Slow horizontal eye movements, SEM) begleitet, ist eine Assoziation mit geistiger Aktivität ausgeschlossen. Ziel dieser Dissertation ist die Untersuchung der Frage, ob niedergespannte EEG-Aktivität im Ruhe-EEG, welche von SEM begleitet wird (B1+), sich von solcher ohne begleitende SEM (B1-) hinsichtlich ihrer spektralen und räumlichen Zusammensetzung unterscheidet. Hierzu wurden 35 Ruhe-EEGs gesunder Probanden analysiert, welche jeweils mindestens 10s B1-, B1+ sowie 10s niedergespannter EEG-Aktivität während der Bearbeitung einer Kopfrechenaufgabe (calc) präsentierten. Unter Verwendung der Methode der standardized low resolution brain electromagnetic tomography (sLORETA) wurden für calc, B1- und B1+ die kortikalen Stromdichteverteilungen in vier verschiedenen, individuell angepassten Frequenzbändern berechnet. Die statistische Auswertung ergab signifikante Unterschiede zwischen B1- und B1+: Es zeigte bei B1- sowohl im Delta- als auch im Theta-Band eine geringere Aktivität im Bereich des Cingulums sowie benachbarten Teilen der Frontal-, Parietal- und Okzipiallappen. Zusätzlich zeigte sich eine erhöhte Aktivität im Frequenzbereich des Beta-Bandes in den Temporallappen für B1- verglichen mit B1+. Der Vergleich von calc mit B1+ erbrachte ähnliche Resultate. Die Befunde lassen eine Zugehörigkeit von B1- zu einem, verglichen mit B1+ höheren Vigilanzniveau vermuten und liefern Evidenz für die Einteilung niedergespannter Episoden im Ruhe-EEG in solche mit und ohne begleitende SEM.
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Fabrication of laterally stacked spin devices by semiconductor processingGhosh, Joydeep 04 December 2013 (has links)
This work presents a new approach of fabricating arrays of electrodes, separated by sub-micrometer gaps allowing the systematic investigation of electric properties of organic semiconductors. The laterally stacked devices are fabricated by using a trench isolation technique for separating different electrical potentials, as it is known for micromachining technologies like Single Crystal Reactive Ion Etching and Metallization (SCREAM). The essential part of this process is the patterning of sub-micrometer trenches onto the silicon substrate in a single lithographic step. Afterwards, the trenches are refilled by SiO2 to allow the precise tuning of the electrode separation gap. The metal electrodes are formed via magnetron sputtering. This technological approach allows us to fabricate device structures with a transport channel length in the range of 100-250 nm by conventional photolithography. In this experiment, three different metals like Au, Co, and Ni were used as the electrode materials, while copper phthalocyanine, being deposited by thermal evaporation in high vacuum, was employed as the organic semiconductor under evaluation. The final aim has been study of spin transport through the organic channel in varied geometry.
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Micromechanical Investigation of the Effect of Refining on the Mechanical Properties of the Middle Ply of a Paperboard.Sandin, Sofia January 2014 (has links)
Optimized fiber utilization is crucial to the process efficiency and profitability in paper and board making. The fibers can be developed in a refining process in order to reach a desired quality level. Refining causes a variety of simultaneous structural changes to the fibers such as internal fibrillation, external fibrillation and fines formation that contribute in different ways to improve the sheet consolidation and enforce bonding between fibers. This increases the strength, which is one of the quality parameters of paper. Three grades of refining are studied. Microscopy of the pulps shows that the fines are not a homogeneous fraction. However, in analyzing SEM images of the handsheet surfaces, fibrillar fines and their bundles are observed to form links between neighboring fibers which can reinforce the network and the bond regions. The fiber characterization method by FiberLab only captures trends in changed fines content in the pulps and these are underestimations since the instruments optical resolution is limited in characterizing fibrillar fines. SEM images of the cross sections of the sheets along with thickness measurements show that increased grade of refining causes a densification of the sheets. Tensile tests show that refining results in a significant increase in tensile strength and stiffness but a more modest increase in strain at break. A 3D fiber network model is built with a deposition technique according to experimental results. Introducing fines in the same way as fibers and increasing the amount of fibrillar fines does not affect the thickness significantly. The densification is instead captured either by changing the width-to-height ratio of the fiber cross sections or by changing the flexibility of the fibers through the so-called interface angle, both having a large impact on the thickness. But SEM images suggest that the width-height-ratio did not reveal a significant change between the three grades of refining. The effect of refining on the mechanical properties is studied numerically using micromechanical simulations which assist interpretation of experimental results. The FE network simulations show that the thickness change alone cannot explain the increased stiffness observed in physical experiments. The addition of fines fraction modelled to capture the fibrillar fines observed in SEM images proved to have a large impact on stiffness comparable to that of experiments. Thus the increased stiffness is partly due to increased number of contacts after densification and partly due to the addition of fines. / Optimerad användning av fibrerna är avgörande för processeffektivitet och lönsamhet i tillverkningen av papper och kartong. Fibrerna kan vidareutvecklas genom ytterligare mekanisk malning för att nå önskad fiberkvalitet. Malning leder till en mängd simultana strukturförändringar av fibrerna såsom inre fibrillering, yttre fibrillering och bildning av så kallade fines, finare partiklar, som på olika sätt bidrar till att förbättra pappersarkens sammansättning och förstärka bindningen mellan fibrer. Detta förbättrar pappersstyrkan vilken är en av kvalitetsparametrarna hos papper. Tre malgrader har studerats. Mikroskopbilder av pappersmassan visar att de finare partiklarna inte är en homogen sammansättning. Men i analysen av SEM bilder av pappersarkens ytor så kan fibriller och grupper av fibriller observeras bilda länkar mellan angränsande fibrer vilka kan förstärka fibernätverket och fibrernas bindningsregioner. Fiberkarakteriseringsmetoden utförd av FiberLab kan bara fånga trender i mängden fines i pappersmassorna och dessa är underskattningar eftersom instrumentets optiska upplösning är begränsad i karakteriseringen av fibriller. SEM bilder av arkens tvärsnitt tillsammans med tjockleksmätningar visar på att ökad malgrad resulterar i en förtätning av arken. Dragprov visar att ökad malgrad leder till en märkbar ökad styrka och styvhet men en något blygsammare ökning i töjningsgräns. En 3D fibernätverksmodell skapas med en depositionsteknik enligt experimentella resultat. Genom att introducera fines på samma sätt som fibrer och öka antalet visade sig inte ha någon signifikant inverkan på nätverkets tjocklek. Istället fångas förtätningen av arken på två andra sätt i genereringen av fibernätverket, antingen genom ändring av bredd-höjd kvoten av fibrernas tvärsnitt eller genom förändring av fibrernas flexibilitet med användandet av den så kallade interfacevinkeln, vilka båda har stor inverkan på tjockleken. Men SEM bilder av tvärsnitten visade ingen stor skillnad hos bredd-höjd kvoten mellan de tre malgraderna. Malgradens påverkan på de mekaniska egenskaperna studeras numeriskt genom mikromekaniska simuleringar, vilka jämförs med experimentella resultat. Finita element simuleringarna visar att tjockleksändringen inte ensamt kan förklara den ökade styvheten som observerats i dragproven. Tillägget av fines modellerade att fånga fibrillernas egenskaper observerade i SEM bilder visade sig ha en stor inverkan på styvheten, jämförbar med dragproven. Alltså, den ökade styvheten beror dels på ökat antal kontaktpunkter efter förtätning av arken och dels på innehållet av fines.
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Characterization of non-metallic inclusions according to morphology and composition : A comparison of two different steels before and after turningGram, Tove, Vickerfält, Amanda January 2015 (has links)
Investigation of non metallic inclusions in two different steels from Sandvik was made before and after turning. After dissolving the non-metallic inclusions by electrolytic extraction the particles were analysed manually or by INCA feature. This was referred to as 3D analysis. INCA feature analysis without extraction of particles was also performed, this was referred to as 2D analysis. The aim of the report was to a make a characterization of non-metallic inclusions with respect to chemical composition, aspect ratio, size and shape. The aim was also to compare different investigation methods. Samples were prepared and investigated. It was obtained that inclusions with sulphur content was elongated and crushed during the turning process. Broken sulphides were detected in one of the steels, and broken oxysulphides in the other steel in the electrolytically extracted chips created by turning. The first steel, steel 1, mainly contained sulphide and oxysulphide inclusions, and steel 2 mainly contained oxysulphides. The aspect ratio obtained by 2D analysis of the sulphide inclusions in steel 1 before turning showed similar results to the electrolytic extracted inclusions measured by hand. The aspect ratio increased with the length of the inclusion. However the deviation of data obtained by the 2D analysis was larger than deviation from the extracted particles measured by hand. The reason for this was assumed to be that the 2D method was not able to analyse the true shape of the inclusions e.g. if inclusions were partly concealed by metal matrix. In analysis of steel 2 the average aspect ratio decreased for oxides and increased for oxysulphides after turning. The chemical composition of inclusions did not change after the turning process for neither of the steels. Copper was detected in the electrolytic extracted inclusions, however not in the 2D investigation by SEM. This is an interesting topic for future research.
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Acciones de la promoción digital en relación con el proceso de compra de ropa Plus Size en mujeres de 18 a 34 años de NSE B de Lima Metropolitana / Actions of digital promotion in relation to the process of buying Plus Size clothing in women from 18 to 34 years of age from NSE B of Metropolitan LimaChuquilin Zelada, Fiorella Elizabeth 10 July 2020 (has links)
El presente trabajo de investigación académica está basado en el análisis de las acciones de la promoción digital en relación con el proceso de compra de ropa Plus Size en mujeres de 18 a 34 años de NSE B de Lima Metropolitana. En primer lugar, se dan a conocer cuales son las estrategias SEO y SEM, así mismo detalla cuales son las acciones comprendidas dentro de estas estrategias. Además, se investiga sobre la reacción del target a estas acciones y estímulos. En segundo lugar, se tomó muy en cuenta el análisis del proceso de compra de las mujeres del segmento, descubriéndose que el target prefiere realizar compras por internet antes que las tiendas físicas. Finalmente, se contrastaron ambas variables y se evaluó la influencia de las diferentes estrategias de marketing digital en las etapas del proceso de compra del segmento Plus Size. Adicionalmente, se presenta el contraste de los resultados con la hipótesis planteada y conclusiones de la investigación. / This academic research work is based on the analysis of the actions of digital promotion in relation to the process of buying Plus Size clothing in women from 18 to 34 years of age from NSE B of Metropolitan Lima. First of all, they are disclosed which are the SEO and SEM strategies, as well as detailing what are the actions included within these strategies. In addition, the target's reaction to these actions and stimuli is investigated. Secondly, I am very aware of the analysis of the purchasing process of women in the segment, discovering that the objective of making purchases online before physical stores. Finally, both variables were compared and the influence of the different digital marketing strategies in the stages of the Plus Size segment purchasing process was evaluated. In addition, the contrast of the results with the hypotheses and the conclusions of the investigation is presented. / Trabajo de investigación
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